US3880586A

US3880586A - Apparatus for sterilizing ampoules and reject control system therefor

Info

Publication number: US3880586A
Application number: US421676A
Authority: US
Inventors: Teruo Murayama; Mamoru Irizuki; Yuichi Morishita; Isamu Utsumi; Kanae Murakami; Hiroichi Matsushita
Original assignee: Jeol Ltd
Current assignee: Jeol Ltd
Priority date: 1972-12-07
Filing date: 1973-12-04
Publication date: 1975-04-29
Anticipated expiration: 1992-04-29
Also published as: DE2360646B2; GB1446187A; JPS534357B2; NL7316633A; CH572748A5; FR2209587A1; DE2360646A1; IT1000221B; FR2209587B1; JPS4979091A; NL157503B

Abstract

An apparatus for treating liquid filled ampoules at a temperature high enough to sterilize but not high enough to cause destruction of the ampules and their contents, for example, liquid medicine. A substantially fail-safe detection and rejection system measures the temperature of each ampoule after sterilization and sorts out those heated to a temperature outside the acceptable range. The system includes checks of the power supply, black body reference temperature, pyrometer operation, and the synchronizing pulse system and rejects not only those ampoules out of temperature but a certain number of ampoules tested before the system becomes defective and after it has been restored to proper order as well as those tested while the system is defective.

Description

United States Patent Murayama et al.

1451 Apr. 29, 1975 [5 1 APPARATUS FOR STERILIZING 3.356.212 12/1967 Landin 209/1115 AMPOULES AND REJECT CONTROL 3.587 855 6/1971 Roy 1 1 209/1115 SYQTEM THEREFOR 3.747.755 7/1973 Scnturia et a1 209/1115 [75] Inventors: Teruo Murayama, Niiza; Mamoru FOREIGN PATENTS OR APPLICATIONS Irizllki, Kunitachi; Yuichi 1029.792 12/1970 Germany 21/102 R Morishita, Akikawa, both of Tokyo; f p f f v y Kanae Primary Examiner-Barry S. Richman Murakaml; Hlmlch' Matsushltav Assistant E.\'amincr-Bradley R. Garris both of Toyomlku, of Japan Attorney, Agent, or Firm-Webb, Burden, Robinson & 173 Assignees: Nihon Denshi Kabushiki Kaisha, Webb Tokyo; Tanabe Seiyaku Co., Ltd..

Osaka. both of Japan 57 ABSTRACT [22] Filed: Dec. 4, 1973 An apparatus for treating liquid filled ampoules at a temperature high enough to sterilize but not high 7 [211 App! NO 421 6 6 enough to cause destruction of the ampules and the1r contents, for example, liquid medicine. A substantially [30] Foreign Application Priority Data fail-safe detection and rejection system measures the Dec. 7. 1972 Japan 47-122880 temperature of ach mpoule after sterilization and sorts out those heated to a temperature outside the ac [52] U.S. C1 21/102 R; 21/54 R; 21/80; cepmble range. The system includes checks of the 21/103; 21/105; 209/1115 power supply, black body reference temperature. py

[51 1 Int. Cl A61] 3/02; B07c 5/34; B07c 5/344 rometer operation, and the synchronizing pulse system 158] Field of Search 21/54 R, 80, 102 R. 105; n r jects not only those ampoules out of tempera- 219/1 55 R, 1055 A 55 (3; 99/334 360 ture but a certain number of ampoules tested before 362, 483; 426/241; 209/1 1 1.5 the system becomes defective and after it has been restored to proper order as well as those tested while the [561 References Cited system is defective UNITED STATES PATENTS 28 Claims, 14 Drawing Figures 3.341.010 9/1967 Switzer 209/1115 Power Ch k (13'c fro/11b term/111112 1511 Power /5 L [c 430 Source i Cuunter Pyrometer 1 ,6 Check l 1/ Generator W, [50 1 1 Signal Po we "4 1/00 1 Prncessi y Source g 5 522C il/fie J $5 ['71 I Magnetron GUS/*6 0/ 5L awe Power (2 a b Source 6 Sourc +l 5 7 211d S nc 1, '1 Ag}; Generetar 1 30b i 300. 1

1 1 1 l I3 [I [a 4 l3 I3 I 1 6b 4 Pawer l0 0- Black 5011/ /4 50 1/ rce [21, check ['7 FKI'ENTEEAPR 2 9 38. 5

SHEET BF 6 APPARATUS FOR STERILIZING AMPOULES AND REJECT CONTROL SYSTEM THEREFOR This invention relates to an apparatus for sterlizing liquidfilled ampoules with microwave radiation and particularly to an apparatus for automatically sorting acceptable and unacceptable ampoules according to the temperatures of the ampoules after they have undergone a sterilizing treatment.

For producing sterile liquid agents such as medicinal injection agents. filled ampoules are generally given sterilizing treatment including external heating in a heated bath or steam of liquid. As a substitute for the external sterilizing method described. another method comprising irradiating the sealed ampoules of such medicinal liquid with microwaves having a frequency of about 300 to 10.000 MHz for a period of several seconds to several minutes while rotating them has been suggested (German Pat. Publication No. 2,029,792). The medicinal liquid is heated so quickly that there are various advantages. Certain medicinal liquids can be perfectly sterilized by the action of the microwaves without decomposing. Particularly. in the case of scaled ampoules. by rolling them through a heating chamber irradiated with microwaves while maintaining the ampoules properly inclined. the medicinal liquid is agitated in the ampoules and its temperature rises uniformly due to the combined effect of a convection action due to a temperature rise and mixing due to the rotation of the ampoules. This method is adaptable to aatomatically sterlizing many ampoules in sucession. thus improving productivity significantly.

When a medicinal liquid is sterilized by a heating treatment. pyrolysis may occur in the liquid if the heating temperature is too high. Perfect sterilization however. is impossible if the heating temperature is too low. Thus. sterilization has an allowable range and this range is very small. As a result. in the microwave sterilizing method. an ampoule may be heated outside the allowable temperature range due to the combined effect of slight changes in factors such as the strength of the microwave energies. the quantity of enclosed liquid and the microwave radiating time period. In the case of continuous sterilization. the residence time of an ampoule passing through a heating chamber is particularly controlled by the velocity of the ampoule conveying means.

An ampoule heated outside the allowable range of temperature is considered defective because the contents are decomposed or the sterilization is imperfect. Defective ampoules must be sorted without error from the good ampoules heated within the allowable range of temperature.

A purpose of this invention is to offer an apparatus for sterlizing liquid filled ampoules by heating them with microwaves. Another purpose of this invention is to offer a substantially fail-safe apparatus for sorting good ampoules heated within a desired temperature range from defective ampoules heated outside the desired temperature range.

Briefly. according to this invention. an ampoule sterilizing apparatus rolls ampoules successively through a microwave oven. next through a temperature measuring chamber and then to a sorter. The ampoules are moved through the sterilizer by a conveyor having substantially equally spaced receptacles for the ampoules. Preferably. the temperature measuring device comprises for example. a radiation pyrometer and a black body reference arranged such that the pyrometer focuses on the black body reference between successive ampoule temperature measurements. The measuring device and conveyor means are arranged to produce two sets of synchronizing pulses. one set aligned with the measurement of ampoule temperature and the second set aligned with the black body reference temperature measurement. The sterilizer has a circuit associ ated therewith for comparing the actual ampoule temperature with an acceptable range and a delay circuit for opening the sorter to reject out-of-temperature (defective) ampoules when they are conveyed to the sorter. Preferably. the sterilizer is rendered substantially fail-safe by check circuits which check the power supply to the temperature measuring and comparing circuits and other check circuits. the pyrometer operation. the synchronizing pulse circuits and the black body reference temperature. Preferably. the check circuits cause rejection of a certain number of ampoules measured before a defect in the system arises. during the defect. and after the defect is removed. Reference errors in sorting due to sorter malfunction are minimized by having two spaced Sorters each actuated by its own logic circuit.

Further features and other objects and advantages of this invention will be better understood by the following detailed description with reference to the accompanying drawings in which:

FIG. I is a schematic diagram showing an example of a sterilizing apparatus embodying this invention;

FIG. 2 is an oblique view of an example of an ampoule conveying means;

FIG. 3 shows an example of an ampoule sorter:

FIG. 4 is a block diagram showing an example of a radiation pyrometer;

FIG. 5 is a diagram of electric signals in said apparatus according to this invention:

FIG. 6 is a block diagram showing an example of a synchronizing signal generator 601:;

FIG. 7 is a block diagram of a black body reference temperature check circuit;

FIG. 8 is a block diagram of a power supply check circuit;

FIG. 9 is a block diagram of a radiation pyrometer check circuit;

FIG. 10 is a block diagram of a synchronizing signal pulse check circuit;

FIG. 11 shows an example of an integration circuit in the apparatus illustrated in FIG. 10;

FIG. 12 is a schematic diagram showing an example of a logic circuit I30 for combining the output of several check circuits in the apparatus illustrated in FIG. 1;

FIG. 13 is a block diagram showing an example of a signal generating circuit for creating a holding pulse in the apparatus illustrated in FIG. I; and.

FIG. 14 is a block diagram showing an example of a signal processing circuit for comparing the measured ampoule temperature with an acceptable range and instructing the sorter to reject the ampoule when it reaches the sorter in the apparatus illustrated in FIG. 1.

Referring to FIG. I, a heating chamber 1 comprises an oven and/or a wave guide. Microwaves having a frequency. for example. of 2.450 MHz. from the micro wave source 2 such as magnetron are fed into the heating chamber 1 through wave guide 3. The strength of the microwaves from the microwave source 2 are controlled by the power source 4. Adjacent to said heating chamber 1 is a temperature detecting chamber equipped with a typical radiation pyrometer 40 employing an infrared detector and black body reference 10.

A conveyor or conveying means 20 is arranged to roll the ampoules through the heating chamber 1 and the adjacent temperature detecting chamber 5. The direction of the conveyors movement is indicated by the arrow A in FIG. 1. The conveyor 20 comprises spaced receptacles for holding the ampoules a fixed distance I apart. The detecting chamber is arranged to hold at least two ampoules and the intermediate space therebetween at one time. Hence. the detecting chamber defines at least three aisles V2 1 wide. The infrared detector or pyrometer 40 is spaced on one side of the conveyor opposite the black body reference on the other side of the conveyor both being within one side of the aforesaid aisles. The base 12 over which the conveyor rides is provided with openings 12a. 12b. and 120 in each of the aisles described above.

Synchronization or alignment of the position of the conveyor 20 within the heating chamber and the remainder of the system (to be described) is achieved by two timing

lights

6a and 6b and two photodetector tubes 7a and 71). Light 6a and tube 741 are aligned across the conveyor in an aisle. the center of which is place /2l (or 111+]. where n is any whole number) from the center of the aisle for the detector 40 and black body 10, as shown in FIG. 1. The light 612 and tube 7/; are aligned across the conveyor in an aisle. the center of which is spaced 1 (or nl) from the center of the aisle for the detector and black body reference. Since the conveyor 20 has openings 13 equally spaced between the ampoule receptacles which become aligned between the lights and detectors as the conveyor moves by. phototube 7h produces a pulse when the pyrometer 40 is directed on the black body reference 10 and phototube 70 produces a pulse when the pyrometer 40 is directed upon an ampoule.

In the particular embodiment shown in FIG. 1,

holes

12a, 12b and 120 are spaced /2/ apart on the base 12. On opposite sides of the base radiation pyrometer 40, black body 10 and hole 12a align, the phototube 7a, light source 6a and hole 121; align and the phototube 7!), light source 6b and hole 12c align. The holes 13 in the conveyor between adjacent ampoule receptacles pass over the holes 12a. 12b and 12c in order as said conveying means 20 moves on. Therefore. at one instant. as the conveying means 20 moves on. the radiation receiving face of the radiation pyrometer 40 is irradiated by infrared radiation emitted from the ampoule 11 moving below and at a later instant the pyrometer is irradiated by infrared radiation emitted from the conveying means 20 and from the black body reference 10.

The infrared beams are transduced to electric temperature signals by the radiation pyrometer 40. The de' tected temperature and reference signals are supplied to the pyrometer check circuit 90 and the signal processing circuit 150.

The phototubes 7a and 7b transduce the beams from the

light sources

6a and 6b to electric signals as a hole 13 on the conveying means 20 passes above the holes 12!: and 120 of the base 12, and these detected signals are supplied respectively to synchronizing signal generators 60a and 60b, which generate the first and second synchronizing signals. respectively on the basis of the input signals.

The first synchronizing signal generated by the syn chronizing signal generator 60a aligns with the meas urement of the temperature of the ampoule 11 by the pyrometer 40, since the pitch between two adjacent ampoule receptacles of the conveying means 20 is twice the interval (V2!) between the holes 12a and 12b. The first synchronizing signal is supplied to the synchronizing signal check circuit 100, signal generating circuit 120, counting circuit 140, and the signal processing circuit 150.

The second synchronizing signal generated by the synchronizing signal generating circuit 60b aligns with the detection of the temperature of the black body reference 10 by the radiation pyrometer 40. The second synchronizing signal is supplied to the check circuits 90 and 100.

The generation of said first and second synchronizing signals invariably aligns with the detection of the temperature of the heated ampoule 11 and that of an infrared beam from the black body reference 10 even though the velocity of the conveying means 20 may vary since the distances of the phototubes 7a and 7b from the radiation pyrometer 40 are /21 and I( l=Pitch of conveyed ampoules 11 respectively.

Said black body reference 10 is maintained at a constant temperature by the power source 14. and the temperature of said black body reference 10 is detected by the check circuit as an electric signal corresponding to said temperature and it is always compared with the reference signal. When the above-mentioned temperature is within the range of the reference signal (normal) said check circuit 70 generates the pulse l and when beyond the range (abnormal) the circuit generates the pulse 0". Said pulse is supplied through the terminals 15a and 15b to the logic circuit 130. By checking the temperature of the black body reference 10 in this manner. mixing of good ampoules with defective ampoules due to a change of the black body reference temperature can be prevented.

The power supplied by the power source 16 to all circuits is compared .with a reference signal by the check circuit 80. When the power source 16 is within the range of the reference signal (normal) said check circuit generates the pulse 1. and when beyond the range (abnormal) said circuit 80 generates the pulse 0. Either pulse is supplied to the logic circuit 130. By checking the output of the power source 16 in this manner. mixing of good ampoules with defective ampoules due to all circuit error resulting from an unstable supply voltage can be prevented.

The pyrometer check circuit of the radiation pyrometer 40 extracts a reference signal corresponding to the detected temperature of the reference temperature source maintained at a known constant temperature. and checks whether said extracted signal is a desired value and whether the radiation pyrometer 40 is normally operating. Therefore. the pyrometer check circuit 90 extracts a temperature signal of the black body reference 10 which is the reference temperature source. out of the temperature signals which were detected by the radiation pyrometer 40 by using the sec ond synchronizing signal and compares said temperature signal with the reference signal. When said temperature signal is within the range of the reference signal (normal) said pyrometer check circuit 90 generates the pulse 1, and when beyond the range (abnormal) the circuit 90 generates the pulse (I. Said output pulse I or is supplied to the logic circuit 130.

The check circuit 100 checks whether synchronizing signals fed by the synchronizing signal generators 60a and 60h are normal. When normal. said check circuit generates the pulse 1 and when abnormal. the circuit generates pulse 0. Said output pulse l or (I is supplied to the logic circuit 130.

The logic circuit 130 generates the pulse 1 when all input signals are a pulse 1 (normal) and said circuit generates the pulse 0 when any of the input signals is the pulse 0 (abnormal). Said output pulse 1 or O is supplied to the signal processing circuit 150 and to signal generator 120. The logic determines whether all the ampoule sterilization apparatus is normal since the input signals are supplied from the check circuits 70. 80. 90 and 100.

On the basis of the first synchronizing signal from the synchronizing signal generator 60a and the pulse 1 or 0 from the logic circuit 130, the signal generator 120 generates an abnormality signal for an extended certain period of time. Accordingly. when the output pulse of the logic circuit 130 is 0 (any part of the apparatus is abnormal) at the time of a given first synchronization signal and for a time after the output of all circuits returns to normal. ampoules are condemned until the apparatus stabilizes. Therefore. the reliabilty of the apparatus improves significantly. The output pulse I (normal) or 0 (abnormal) of said signal generator 120 is supplied to the signal processing circuit 150.

By comparing the ampoule temperature signal with the reference signal. the signal processing circuit 150 checks whether the ampoules passing below the light receiving face of the radiation pyrometer 40 have been heated to a desired temperature range and generates the logic outputs of said check signal and other input signals. The logic outputs are good-ampoule signals only when all input signals are normal. and defective ampoule signals when any of the signals are abnormal.

The output signal of said signal processing circuit 150 is supplied to the power sources 17a and 17b and the counting circuit 140. The power sources 17:: and 17b drive the

ampoule sorters

30a and 30b to drop defective ampoules through the

holes

12d and 120 provided in the base 12, only when a defective ampoule signal has been supplied or the system is defective. The counting circuit 140 counts good'ampoule signals and defectiveampoule signals separately.

The

ampoule sorters

30a and 30b are provided in positions spaced apart from the temperature detector 5 by integral multiples of the pitch (1) between two ampoules of the conveying means 20, for example. by 101 and 8/. respectively. Accordingly. the signal processing circuit 150 contains two time adjusting circuits differing in time lag so as to equalize the time from the detection ofthe ampoule temperature by the radiation in py' rometer 40 until the operation of the ampoule sorters on the basis of said detection signal and the time until a temperature measured ampoule is conveyed from the lower side of radiation pyrometer 40 to the ampoule sorters a and 30h. By providing a plurality of ampoule sorters in this manner. it is possible to compensate for a malfunction for one ampoule sorter with the other ampoule sorter. and as a result. defective ampoules and good ampoules can be more correctly sorted out.

FIG. 2 is an oblique view showing an example of the conveying means 20 for the apparatus illustrated in FIG. 1. The conveying means consists of the belt moving continuously on the base 12 in the direction indicated by the arrow and the conveying body 22 attached to said belt conveyor 21. Said conveying body has slender cogs 23 arranged to roll the ampoules 11 over the base 12. The couplers 24 join said cogs at their ends. Each cog 23 has the above-mentioned hole 13. The coupler 24 has the same width as that of the belt conveyor 21, and it is fastened to the belt conveyor 21.

The ampoules 11 and material to be heated are positioned in ampoule receptacles between cogs 23 and are conveyed in direct contact with the base 12 which is inclined to the vertical line to the extent that an enclosed liquid may not enter the branch part of the ampoule while the ampoule is rotated by cog 23 in the direction indicated by the arrow B and a contact resistance (frictional force) between the ampoule and the base 12. To convey an ampoule as inclined to the vertical line. the base 12 and the conveying means 20 may be inclined beforehand so that the branch of the ampoule should be up. An optimum inclination angle of an ordinary one milliliter ampoule with respect to said vertical line is 45 to But said inclination varies according to the kind and shape of the ampoule.

The ampoule drop preventing supporter 25 integrated with the coupler 24 prevents an ampoule being conveyed as inclined from dropping from the ampoule receptacle of the conveying means 20.

Slots

12d and 12 in the base 12 slightly larger than the barrel part of an ampoule are provided at certain distances (for example 101 and 81) from the hole 12a (refer to FIG. 1) in the downstream direction (in parallel with the ampoule). Below the holes 12d and l2e are the ampoule sorters 30a and 3011 (refer to FIG. 1).

To convey an ampoule properly inclined. it is desirable that the surface of the base 12 contacting the ampoule 11 should be slightly uneven. Thereby, since a contact resistance (frictional force) between the base 12 and the ampoule 11 becomes by far larger than that between the cog 23 and the ampoule 11, the ampoule can be securely rotated. The entire surface need not be uneven.

If the cog 23 has a trapezoidal cross section as shown in FIG. 2, the ampoule can be more securely rotated. since a pressure of the cog 23 produces a component of force pushing up on the ampoule 11. In this case, an optimum angle 6 (see FIG. 2) is to about FIG. 3 shows an example of the ampoule sorters 30a (or 30h) illustrated in FIG. 1. The ampoule sorters have. as mentioned earlier. a sliding door 31 provided below the hole 12d (or of the base 12. and a solenoid mechanism 32 for controlling the movement of said sliding door 31. The door is integral with the end of the moving shaft 33 of the solenoid mechanism 32, and blocks the hole 12d (or 120) of the base 12 with the aid of the coil spring 34. A stopper 35 limits the lengthwise movement of the door.

In this ampoule sorter. if a signal is supplied by the power source 17a (or 1717) the moving shaft 33 is drawn against a force of the coiled spring 34 and the door 31 moves in parallel with the base 12 to open the hole 12:! (or 120). Accordingly. the ampoule passing through said ampoule sorter 3011 (or 30h) drops as indicated by the broken line and is removed by the guide 36.

If a signal from the power source 1711 (or 17b) is shut off. the movable piece 31 blocks the hole 12:! (or 120) again with the aid of a force of the coiled spring 34.

FIG. 4 is a schematic diagram showing the parts of the radiation pyrometer 40. The pyrometer comprises a chopper plate 42 driven by motor 41 at a constant angular velocity. The chopper plate is provided with equally spaced slits 42a. The infrared detector 44 detects infrared beams passing through the slits 42a of the chopper plate 42 and converts the beams into signals according to their intensity. This signal is then operated upon by amplifier 45, band pass filter 46 synchronizes rectifier 47 and low pass filter 48. The radiation pyrometer also comprises a synchronizing signal generator which generates a signal aligned with the chopping frequency for the infrared beam. The generator is aligned by a timing signal created by a phototube 50 which is actuated by a light from lamp 49 passing through slits 42a of chopper plate 42. The pyrometer cooperates with a black body reference 43 set at a temperature (for example 120C) approximately equal to that of a heated ampoule.

In this apparatus as heated ampoules have been conveyed successively by the conveying means 20 below the light receiving face of the radiation pyrometer 40 as shown in FIG. 1, the intensity of the infrared beam reaching the chopper plate 42 changes as shown in FIG. (a). In this figure. 55 shows the intensity of the infrared beam radiating from the heated ampoules, 56 shows the intensity of the infrared beam radiating from the conveying means 20 and 57-shows the intensity of the infrared beam radiating from the black body (refer to FIG. I). Said infrared beams are chopped by the chopper plate 42 with a frequency of lKHz, for example, and the infrared beam radiating from the black body 43 and said infrared beams reach the infrared detector alternately.

Said infrared beams are converted by the infrared detector 44 as electric signals according to their intensity and supplied through the amplifier 45 to the band pass filer 46. The band pass filter 46, having a passing bandwidth around the frequency (for example lKHz) which chopped the above-mentioned infrared beams, supplies signals to the synchronous rectifier 47. The synchronous rectifier 47 is supplied with a synchronizing signal which synchronizes with the chopping frequency of the above-mentioned infrared beams from the synchronizing signal generator 51. Said synchronous rectifier 47 synchronously rectifies the input signal from the band pass filter 46 with the aid of said synchronizing signal and supplies the signal to the low pass filter 48.

The low pass filter 48 eliminates the high frequency components in the input signal and supplies the signal as a temperature signal through the output terminal 52 to the check circuit 90 and the signal processing circuit 150 in FIG. 1. The output signal of the low pass filter 48 has the same form as the wave form in FIG. 5 (h) namely, that of the infrared beam reaching the chopper plate 42.

FIG. 6 is a block diagram showing an example of the first synchronizing signal generator 60a illustrated in FIG. I. Said synchronizing signal generator has an amplifier 61 which amplifies the input signal from the phototube 7a. The wave forming circuit 62 generates the first synchronizing signal as shown in FIG. 5 (c). The

output of said wave forming circuit 62, namely. the first synchronizing signal synchronizes with the ampoule temperature signal among the temperature signals which are supplied from the radiation pyrometer 40 to the signal processing circuit 150 as mentioned earlier. The first synchronizing signal is supplied through the terminal 63 to the check circuit 100, signal generating circuit 120, counting circuit 140, and the signal pro cessing circuit 150. The synchronizing signal generator shown in FIG. 6'can be used as the second synchronizing signal generator 60b of the apparatus illustrated in FIG. 1. In this case, the output of the wave forming circuit. namely, the second synchronizing signal synchro nizes as shown in FIG. 5(d). with the black bodytemperature signal among the temperature signals which are supplied from the radiation pyrometer 40 to the signal processing circuit 150. H

FIG. 7 is a block diagram showing an example of the black body reference check circuit in the apparatus illustrated in FIG. I. Said circuit comprises the temperature detecting circuit 71 which detects the temperature of the black body 10 as an electric signal, upper and

lower limit detectors

72 and 73 which compare the output of said temperature detecting circuit 71 with the upper and lower reference signals. reversing circuit 74 which reverses the output of said detector 72, the NAND circuit 75, which generates the NAND output of said reversing circuit 74 and that of the lower limit detector 73, and the reversing circuit 76 which reverses said NAND outputs. v

The temperature detecting circuit 71 may be a bridge type circuit combining a thermistor (which is an element the resistant value of which varies with temperature) and three resistors. The thermistor or the like is positioned within the black body. Thus. a signal (voltage) generated across the bridge circuit corresponds to a temperature change in the black body 10. This signal is supplied to the upper limit detector 72 and the lower limit detector 73 where it is compared to upper limit and lower limit reference signals respectively.

The reference signal of the upper limit detector 72 corresponds to the temperature detector output signal when the temperature of the black body is at its upper acceptable limit. When the input signal from said temperature detector 71 is over the reference signal value (abnormal) the pulse 1 is generated. and when below the reference signal value (normal) the pulse 0 is generated. Said pulse 1' or 0 is supplied the NAND circuit after it is reversed by the reversing circuit 74.

The reference signal of the lower limit detector 73 corresponds to the temperature detector output signal when the temperature of the black body is at its lower acceptable limit. When the input signal from the abovementioned temperature detector 71 is over the reference signal value (normal) the pulse 1 is generated, and when below the reference signal value (abnormal) the pulse 0 is generated. Said pulse 1 or 0 is supplied to the NAND circuit 75.

The NAND circuit 75 generates the pulse 0 when both input signals are l namely, the temperature of the black body 10 is within the allowable range (normal) and it generates the pulse 1 when either of the input signals is thepulse 0 (abnormal). Said NAND is supplied through the terminal 77 to the logic circuit after it is reversed to l or O by the reversing circuit 76. Therefore. the output pulse of said check circuit 70 is I when the temperature of the black body is normal and when abnormal.

FIG. 8 is a block diagram showing an example of the power supply check circuit 80 in the apparatus illustrated in FIG. 1. Said circuit comprises the upper and

lower limit detectors

82 and 83 which compare a signal supplied through the terminal 81 from the power source 16 with the upper and lower reference signals. circuit 84 which reverses the output of the upper limit detector 82, NAND circuit 85 which generates the NAND outputs for the output of said reversing circuit 84 and that of said lower limit detector 83 and the reversing circuit 86 which reverses the output of said NAND circuit 85.

The functions of the

circuits

82, 83, 84, 85 and 86 composing said check circuit are respectively the same as those of the

circuits

72, 73, 74, 75 and 76 composing the check circuit shown in FIG. 7. Therefore, a signal supplied through the terminal 87 to the logic circuit 130 is the pulse 1 when the output of the power source 16 is normal, and the pulse 0 when abnormal.

FIG. 9 shows an example of the pyrometer check circuit 90 in the apparatus illustrated in FIG. I. Said circuit 90 comprises the sample hold circuit 93 which samples a temperature signal corresponding to the temperature of the black body (refer to FIG. 1) among temperature signals supplied from the radiation pyrometer 40 to the input terminal 91 with the aid of the second synchronizing signal supplied to the input terminal 92 and which holds said sampled signal until the next sampling. upper and lower limit detectors 94 and 95 v which compare the sample with the upper and lower reference signals, reversing circuit 96 which reverses the output of the upper limit detector 94, NAND circuit 97 which generates the NAND outputs for the output of said reversing circuit 96 and that of said lower limit detector 95, and the reversing circuit 98 which reverses the output of said NAND circuit 97.

The reference signal values set in the abovementioned upper and

lower limit detectors

94 and 95 are the upper and lower acceptable limit values of the temperature signal of the black body 10 supplied from the above-mentioned circuit 93. The functions of said upper and

lower limit detectors

94 and 95, reversing

circuits

96 and 98, and the NAND circuit 97 are respectively the same as those of the

detectors

72 and 73, reversing

circuits

74 and 76, and the NAND circuit 75 illustrated in FIG. 7. Accordingly, said check circuit 90 generates the pulse 1 when the radiation pyrometer 40 is normal and the pulse 0 when abnormal.

FIG. 10 is a block diagram showing an example of the synchronizing signal check circuit 100 in the apparatus illustrated in FIG. 1. Said circuit checks whether the first and second synchronizing signal generating circuits 60a and 6011 are normal and whether the first and second synchronizing signals are normal and condemns all the signals temporarily stored in the time adjusting circuit in the signal processing circuit 150 in case said synchronizing signals are abnormal. In this circuit, the first synchronizing signal is supplied to the terminal 101, the second synchronizing signal is supplied to the terminal 102. These synchronizing signals are wave formed by the

wave forming circuits

103, 104 and 105.

In the up-down counter 106, the first synchronizing signal is supplied from the wave forming circuit 103 to the adding terminal, the second synchronizing signal is supplied from the wave forming circuit 104 to the subtracting terminal and the output of the monostable multivibrator 109 is supplied to the clear terminal. Since the counter 106 activates in order to add the first synchronizing signal for addition and to subtract the second synchronizing signal for subtraction, when the fiist and second synchronizing signals are normal, the output is always the pulse 0 and when either of the synchronizing signals is abnormal for instance, either is absent or it contains a noise, the output is 1 since counting is performed in the positive or negative direction.

In the flip-flop 108, the output of said up-down counter is supplied to the set terminal and the output of the monostable multivibrator 109 is supplied to the reset terminal. The reset output of said flip-flop 108 is the pulse 1 (abnormal) when the output of said counter 106 is the pulse 1 (abnormal), and the pulse 0 (normal) when the pulse 0 (normal).

In the 4-bits counter 107, the reset output of the flipflop 108 is supplied to the clear terminal and the output of the wave forming circuit 103 is supplied to the adding terminal. Therefore, when said reset output is the pulse 1 (abnormal) said counter 107 begins to count. If said counter 107 counts 16 of the first synchronizing signals supplied from the wave forming circuit 103, said counter 107 generates the pulse 1 and supplies it to the monostable multivibrator 109. Said counter I07 continues to generate the pulse l (normal) until and unless it is cleared.

The output of the monostable multivibrator 109 is the constant pulse I when the output of said counter 107 is the pulse l (normal) and the pulse 0 when the pulse 0 (abnormal). Said output is supplied to the clear terminal of said counter 106 and the reset terminal of said flipflop 108. Hence, in abnormal operation. the monostable multivibrator is relaxed and provides no output signal. The up-down counter continues to produce a pulse 0 output until a first or second synchroniz ing pulse is missed. At this time, the counter 106 generates a pulse 1 which cause flip-flop 108 to produce a pulse 1 indicative of the abnormal condition. The abnormal pulse of the flip-flop immediately clears the 4-bit counter which then counts, for example, 16 first synchronizing pulses and then produces an output pulse 1. This pulse triggers the monostable multivibrator which provides a pulse to clear the counter 106 and reset the flip-flop 108. Hence, if a synchronizing pulse is missed, the synchronizing pulse check circuit provides a synchronizing circuit unacceptable for at least the next l6 pulses and then resumes vigilance for missing synchronizing pulses.

The integration circuit 110 comprises, as shown in FIG. 11, the element 171 which is opened and closed by the first synchronizing signal supplied from the wave forming circuit 105, integrating condenser 172 connected in parallel with said element, resistor 173 connected between a DC. power source (not illustrated) and the integrating condenser, and the bias resistor 174. In said circuit, only when the first synchronizing signal is supplied through the terminal 175 to the openclose element 171, said element becomes conductive and discharges electricity from the integrating condenser 172. Therefore, if there is no synchronizing signal, the integrating condenser 172 continues to be charged raising the electric potential. The potential at the terminal 176 is supplied to the comparator 111.

By comparing the potential at the above-mentioned integration circuit 110 with the reference signal, said comparator 111 generates the pulse when said potential is below the reference signal value (normal) and the pulse 1 when over the reference signal value (abnormal). The output of said comparator is supplied through the reversing circuit 114 to the NAND circuit 116. The above-mentioned reference signal value is slightly over the maximum potential obtained when the first synchronizing signal is normal. Thus. by providing the wave forming circuit 105, integration circuit 110 and the comparator 111, it is possible to detect the defective condition that the first and second synchronizing signals are abnormal at the same time.

The NAND circuit 116 generates the pulse 0 only when both the reset output supplied through the reversing circuit 112 to the flip-flop 108 and the output of the reversing circuit 114 are the pulse 1 (normal). and said pulse is supplied through the reversing circuit 115 and the terminal 117 to the logic circuit 130. Therefore, the check circuit 100 of said synchronizing signal generates the pulse 1 only when the first and second synchronizing signals are normal.

FIG. 12 shows an example of the logic circuit 130 in the apparatus illustrated in FIG. 1. Said logic circuit comprises the NAND circuit 131 and the reversing circuit 132. The NAND circuit 131 is supplied with the output of the

check circuits

70, 80, 90 and 100 through the

terminals

133, 134, 135 and 136, and it generates the pulse 0 only when all inputs are the pulse I (normal). The output of said NAND circuit is supplied through the terminal 137 to the signal generator 120 and the signal processing circuit 150 after it is reversed by the reversing circuit 132..

FIG. 13 is a block diagram showing an example of the signal generator 120 in the apparatus illustrated in FIG.

1. When the output of the above-mentioned logic circuit 130 is the pulse 0 (abnormal) said generator generates an abnormality signal (pulse 0) for a certain period of time and condemns all ampoules during such period. The signal generator 120 wave forms the first synchronizing signal supplied through the terminal 126 with the aid of the wave forming circuit 121, supplied said signal to the adding terminal of the 4-bits counter 122 and supplied the output of the above-mentioned logic circuit 130 supplied to the terminal 127, through the reversing circuit 124, to the clear terminal of said counter 122. Accordingly. said counter 122 is cleared when the output of the logic circuit 130 is the pulse 0 (abnormal), and continues to generate a defective signal (pulse 0) until and unless the output of the logic circuit 130 and that of the wave forming circuit 121 generate the pulse 1 (normal). 16 consecutive times. The output of said counter is supplied to the reset terminal of the flip-flop 123. The set terminal of said flip flop 123 is supplied with the output of the above-mentioned reversing circuit 124. Accordingly, when the reset input is the pulse 0 and the set input is the pulse 1 (abnormal). the reset output of said flip-flop generates the pulse 1 and when the reset input is the pulse 1 and the set input is the pulse 0 (normal). it generates the pulse 0. Further. when the reset input is the pulse 0 and the set input is the pulse 0, the previous state remains. That is to say, the reset output of said flip-flop is the pulse 0 only when normal. Said flip-flop output is reversed to the pulse 1 or 0 by the reversing circuit 125, and then is supplied through the terminal 128 to the signal processing circuit 150.

FIG. 14 is a block diagram showing an example of the signal processing circuit in the apparatus illustrated in FIG. 1. The circuit comprises a pair of discriminating circuits 150a and l50h. The discriminating circuit 150a has a check circuit comprising the upper and lower limit detectors 151a and 15241. reversing circuits 153a and 15411 and the NAND circuit a.

The upper limit detector 151a has been set at the reference signal which lies within the allowable range of the upper limit of the temperature signal supplied to the input terminal 166, and the lower limit detector 152a has been set at the reference signal which lies within the allowable range of the lower limit. Like the

detectors

72 and 73 illustrated in FIG. 7, said detectors 151a and 1520 generate the pulse 1 or 0 by comparing the temperature signal with the reference signal. Accordingly, both detectors generate the pulse 1 when the temperature signal is above the allowable range of the upper limit (abnormal) and both detectors generate the pulse 0 when the temperature signal is below the allowable range of the lower limit (abnormal). Further, the upper limit detector 151a generates the pulse 0 and the lower limit detector 152a generates the pulse 1 when the temperature signal is within the allowable range of the reference signal (normal).

The reversing circuit 153a reverses the output I or 0 of the upper limit detector 15111 to O or 1 respectively and supplied said pulse to the NAND circuit 155a.

Said NAND circuit 1550 is supplied the output of the reversing circuit 15311. the output of the lower detector 152a. and the first synchronizing signal through the input terminal 167. Said circuit generates the pulse 0 only when all input signals are the pulse 1 (normal), and when there is the pulse 0 (abnormal) among the input signals. it generates the pulse 0. Accordingly, when the temperature signal (refer to No. 57 in FIG. 5) of the black body 10 (refer to FIG. 1) among the temperature signals supplied to the input terminal 166 have been supplied to the NAND circuit 155a, the output of said NAND circuit is the pulse 1 which is distinguishable from a good-ampoule signal, pulse 0 since the first synchronizing signal is the pulse 0 (refer to FIG. 5 (a) and (6)).

When the ampoule temperature signal is normal, the output of said NAND circuit 1550. as shown in FIG. 5 (e), has a wave form reverse to that of the first synchronizing signal shown in FIG. 5 (c). Said pulse 0 or I is supplied to the NAND circuit 156a after it is reversed to the pulse 1 or 0 respectively, by the reversing circuit 154a as shown in FIG. 5(f).

Said NAND circuit 156a generates the pulse 0 only when a check signal supplied from the reversing circuit 154a and the output of the logic circuit 130 is supplied through the terminal 168 are the pulse 1 (normal) and it generates the pulse 1 on another occasion (where there is any pulse 0 namely. in an abnormal case). Accordingly. the output of said NAND circuit takes such a wave form as in FIG. 5 (e) when both input signals are normal.

The NAND circuit 157:: is supplied with the first synchronizing signal through the terminal 167. It generates the pulse 0 only when the input signal from the abovementioned NAND circuit 156a is the pulse 1 (abnormal) and generates the pulse l on other occasions. This is to say. said NAND circuit continues to the pulse 1 (good ampoule signal) until and unless the input signal from said NAND circuit 156a turns into the pulse 1 (abnormal). Said pulse 1 or O is supplied through the reversing circuit 158a to the flip flop 15%.

The set input of said flip flop 159a. is supplied with the output of said reversing circuit 158a. and the reset input is supplied with the output signal of the NAND circuit 156a through the reversing circuit 160a. Therefore. the set output of said flip-flop continues to generate the pulse 1 (good ampoule signal) until and unless the set input turns into the pulse 1 (defective ampoule signal). The output signal of said flip-flop is supplied to the shift register 161a.

Said shift register 161a is a time adjusting circuit for equalizing the time from the measurement of the ampoule temperature by the radiation pyrometer until the starting of the ampoule sorter 300 according to said temperature signal and the time until the temperature measured ampoule is conveyed from the underside of the radiation pyrometer to the ampoule sorter 30a.

Said shift register 161a is supplied with the first synchronizing signal wave-formed by the wave forming circuit 162a as a clock pulse. Said shift register 161a has ll bits. for example. and the 9th. 10th. llth bits are connected to the NAND circuit 163a. Accordingly, the input signals from the flip-flop are shifted one by one to the last bit by the clock pulse. The signals shifted to the 9th. 10th and llth bits are supplied to the NAND circuit 163a. Therefore. the NAND circuit 163a generates three consecutive defective ampoule signals (pulses 1) when a defective ampoule signal (pulse 0) exists among the input signals.

The output of said NAND circuit 163a is supplied to the NAND circuit 165a after it is reversed by the reversing circuit 164a.

Said NAND circuit 165a is supplied with the outputs of the abovementioned logic circuit 130 and the signal generating circuit 120 through the terminal 168 and 169. Said circuit 165a generates the pulse 0 only when all input signals are the pulse 1 (normal). The output of said NAND circuit is supplied through the terminal 170a to the power source 17a illustrated in FIG. 1.

As mentioned earlier, the power source 17a energizes the ampoule sorter a only when the output of the NAND circuit 165a is the pulse 1 (abnormal).

On the other hand. the above-mentioned discriminating circuit 15012 is the same as the other discriminating circuit except that the number of bits of the shift register 1611) is different. Therefore. the output of the NAND circuit 16511 is supplied to the power source 1712 illustrated in FIG. 1.

The shift register [6112 which is a time adjusting circuit has 9 bits for example. since the ampoule sorter 30b illustrated in FIG. 1 is provided 21 nearer to the temperature detector 5 than the ampoule sorter 30a. Therefore, the 7th. 8th and 9th bits are connected to the NAND circuit 163k.

Hence. as soon as the logic circuit 130 detects a malfunction in the power supply. black body reference. py rometer or synchronizing pulse circuits, it causes NAND 165a to trigger the sorter power supply 17a. The pulse from the signal generator 120 applied the NAND 165a will hold the sorter open for a certain number of synchronizing pulses after the malfunction is corrected and circuit 130 resumes to provide a normal output pulse. in this way a certain number of ampoules reaching the pyrometer before and after the malfunction period may be rejected.

If individual ampoules are not within the temperature range the signal from 164a causes NAND 165a to trigger sorter power supply 17a and thus sorter 30a when the out-of-temperature ampoule reaches the sorter.

In the aforementioned example. an ampoule sorter is so constructed that it is activated by a logic signal output of its check circuit, but a plurality of ampoule sorters may be independently activated by the output signals of their respective check circuits.

Whether the temperature ofa heated ampoule is normal or not can be checked by one of thediscriminating circuits. In this case. if a plurality of ampoule sorters are controlled by the output of the same discriminating circuit. mixing of defective ampoules in good ampoules due to a malfunction of the ampoule sorters themselves can be prevented.

Further a conveying means itself or the section where the aforementioned hole 13 is located may be made from an infrared transmissive material rather than providing the hole 13 in the conveying means.

Having thus described the invention with detail and particularity as required by the Patent Laws. what is desired protected by Letters Patent is set forth in the following claims.

We claim:

I. Apparatus for sterlizing liquid filled ampoules comprising a microwave heating chamber. conveying means for moving said ampoules through said chamber. means for producing a temperature signal indicative of the temperature of each ampoule passed through said chamber. a check circuit means for comparing said temperature signal with reference signals which define an allowable temperature signal range and for generating a reject signal when said temperature signal is outside of the allowable temperature signal range. and an ampoule sorter means which is responsive to the reject signal for rejecting ampoules.

2. Apparatus according to claim 1 wherein said means for producing the temperature signal comprises a radiation pyrometer.

3. Apparatus according to claim 1 wherein said check circuit means comprises a means for comparing said temperature signal with an upper limit reference signal and means for comparing said temperature signal with a lower limit reference signal and a logic circuit means for generating the reject signal.

4. Apparatus for sterilizing liquid filled ampoules comprising a microwave heating chamber. a conveying means for rolling said ampoules through said chamber, a black body reference maintained at a constant temperature. and a control system comprising a radiation pyrometer means for alternately producing a first temperature signal indicative of the temperature of each ampoule passed through said chamber and a second temperature signal indicative of the temperature of said black body reference. a first means for comparing the first temperature signal with a first set of reference signals defining an allowable first temperature signal range and for generating a first reject signal when said first temperature signal is now in the allowable first temperature signal range. and a second means for comparing the second temperature signal with a second set of reference signals defining an allowable second temperature signal range and for generating a second reject signal when said second temperature signal is not within the allowable second temperature signal range and at least one ampoule sorter means for rejecting ampoules. which is responsive to either the-first or second or both reject signals and is positioned adjacent said conveying means and spaced downstream from said pyrometer means. a

5. Apparatus according to claim 4 wherein each said first and second means for comparing and generating comprises a means for comparing said first and second temperature signals from said radiation pyrometer means with upper reference signals and means for comparing said first and second temperature signals from said radiation pyrometer means with lower reference signals and a logic circuit means for generating reject signals.

6. Apparatus according to claim 4 comprising a first signal processing logic circuit means for receiving the first reject signals indicative of out-of-temperature ampoules and at some time later causing the sorter means spaced along the conveying means downstream from the pyrometer menas to when said out-of-temperature ampoules are thereat and comprising deactivated a second signal processing logic circuit means for receiving the second reject signals and for activating sorter means to reject at least any ampoule that was adjacent the pyrometer means at the time said second reject signals were generated.

7. Apparatus according to claim 6 wherein said second signal processing logic circuit means activates said sorter means to reject at least one ampoule that has passed the pyrometer means prior to the reject signals and maintains said sorter means activated to reject at least one ampoule that has not reached the pyrometer means after the discontinuation of said first or second reject signals.

8. Apparatus according to claim 4 comprising means for generating a first synchronizing signal coincident with the production of said first temperature signal indicative of each ampoule temperature, said first means for comparing and generating said first reject signal being responsive to said first synchronizing signal.

9. Apparatus according to claim 8 comprising means for generating a second synchronizing signal coincident with the production of said second temperature signal indicative of the black body reference temperature, said second means for comparing and generating the second reject signal being responsive to said second synchronizing signal.

10. Apparatus according to claim 9 comprising means for comparing said first and second synchronizing signals with a set of synchronizing reference signals defining an allowable synchronizing signal range and generating a synchronization defect signal when said first and second synchronizing signals are not within said allowable synchronizing signal range wherein said ampoule sorter means is also responsive to said synchronization defect signal.

11. Apparatus according to claim 4 comprising a means for independently producing a third temperature signal indicative of the temperature of the black body reference and a third means for comparing said third temperature signal with a third set of reference signals defining an allowable third temperature signal range and for generating a third reject signal when said third temperature signal is not within the allowable third temperature signal range. and wherein said ampoule sorter means is also responsive to said third reject signal.

12. Apparatus according to claim 11 wherein said third means for comparing and generating said third reject signal comprises a means for comparing the third temperature signal with an upper limit reference signal. means for comparing the third temperature signal with a lower limit reference signal and a logic circuit means for generating reject signals.

13. Apparatus according to claim 11 comprising a first signal processing logic circuit means for receiving the first reject signals indicative of out-of-temperature ampoules and at some time later causing the sorter means spaced along the conveying means downstream from the pyrometer means to be activated when said out-of-temperature ampoules are thereat and comprising a second signal processing logic circuit means for receiving the second and third defect signals and for activating said sorter means to reject at least any ampoule that was adjacent the pyrometer means at the time said second or third reject signals were generated.

14. Apparatus according to claim 13 wherein said second signal processing logic circuit means activates said sorter means to reject at least one ampoule that has passed the pyrometer means prior to the reject signals and maintains said sorter means activated to reject at least one ampoule that had not reached the pyrometer means after the discontinuation of said first. second or third reject signals.

15. Apparatus according to claim 11 comprising a power source means for supplying power to at least part of said control system. a fourth means for comparing the power of said power source means with reference signals defining an allowable power range and for generating a fourth reject signal when said power is not within the allowable power range and wherein the ampoule sorter means is also responsive to the fourth reject signal.

16. Apparatus according to claim 15 wherein said fourth means for comparing and generating said fourth reject signal comprises a means for comparing said power with an upper limit reference signal and means for comparing said power with a lower limit reference signal and a logic means for generating reject signals.

17. Apparatus according to claim 15 comprising a first signal processing logic circuit means for receiving the first reject signals indicative of out-of-temperature ampoules and at some time later causing the sorter means spaced along the conveying means downstream from the pyrometer means to be activated when said out-of-temperature ampoules are thereat. and comprising a second signal processing logic circuit means for receiving the second, third and fourth defect signals and for activating said sorter means to reject any ampoule that was adjacent the pyrometer means at the time said second, third. or fourth reject signals were generated.

18. Apparatus according to claim 17 wherein said second signal processing logic circuit means activates said sorter means to reject at least one ampoule that had passed the pyrometer means prior to the reject signals and maintains said sorter means activated to reject at least one ampoule that had not reached the pyrometer means after the discontinuation of said first. second. third or fourth reject signals.

19. Apparatus according to claim 12 comprising a means for generating a first synchronizing signal coincident with the production of said first temperature signal indicative of each ampoule temperature. said first means for comparing and generating sid first reject signal being responsive to said first synchronizing signal.

20. Apparatus according to claim 19 comprising means for generating a second synchronizing signal coincident with the production of said second temperature signal indicative of the black body reference temperature said second means for comparing and generating the second reject signal being responsive to said second synchronizing signal.

21. Apparatus according to claim 20 comprising a fifth means for comparing said first and second synchronizing signals with a set of synchronizing reference generating a fifth reject signal, when said first and second synchronizing signals are not within said allowable synchronizing signal range, wherein said ampoule sorter means is also responsive to said fifth reject signal.

22. Apparatus according to claim 21 comprising a first signal processing logic circuit means for receiving the first reject signals indicative of out-of-temperature ampoules and at sometime later causing the sorter means spaced along the conveying means downstream from the pyrometer means to be activated when said out-of-temperature ampoules are thereat and comprising a second signal processing logic circuit means for receiving said second, third, fourth and fifth defect sig nals and for activating said sorter means to reject at least any ampoule that was adjacent the pyrometer means at the time said second, third, fourth or fifth defect signals were generated.

23. Apparatus according to claim 22 wherein said second signal processing logic circuit means activates said sorter means to reject at least one ampoule that had passed the pyrometer means prior to the reject signals and maintains said sorter means activated to reject at least one ampoule that had not reached the pyrometer means after the discontinuation of said first, second, third, fourth or fifth reject signals.

24. Apparatus for sterilizing liquid filled ampoules comprising a microwave heating chamber, means for conveying ampoules through said chamber having ampoule holding receptacles and openings at respectively equidistant intervals, said openings being spaced between said equidistant ampoule receptacles, a radiation pyrometer means for producing a temperature signal on one side of said conveying means, a black body reference provided on the opposite side of said conveying means aligned transversely with said radiation pyrometer means, said radiation pyrometer means and black body reference both being positioned so as to align with said openings in said conveying means, a means for comparing pyrometer means a temperature signal corresponding to each ampoule temperature with ampoule reference signals defining an allowable ampoule temperature range and for generating a first reject signal when said pyrometer means ampoule temperature signal is not within the allowable ampoule temperature range, and means for comparing a pyrometer means temperature signal corresponding to the black body reference temperature with black body reference signals defining an allowable black body temperature range and for generating a second reject signal when said pyrometer means black body temperature signal is not within the allowable black body temperature range and at least one ampoule sorter means which is responsive to either the first or second or both reject signals for rejecting said ampoules.

25. Apparatus according to claim 24 wherein said ampoule holding recepticles are defined by a plurality of cogs arranged parallel to each other and at equidistant intervals on the ampoule conveying means.

26. Apparatus according to claim 25 wherein the lower ends of the cogs are joined together by coupling plates, thereby forming said conveying means.

27. Apparatus according to claim 26 wherein means is provided on each said coupling plates to prevent said ampoules from inadvertantly falling off of said conveying means.

28. Apparatus according to claim 27 wherein the cross-section of the cogs is trapezoidal in shape.

UNITED STATES PATENT OFFICE CETTFTCATE 0F CQRECTIQN PATENT NO. 3, 880, 586

DATED 1 April 29, 1975 |NVENT0R(5) 1 Teruo Murayama et a1.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown beiow:

Column 3 Line 30 --l/2 Q(or nX-i Q. should read Claim 4 Column 14 Line 60 noW-- should read --not--.

Claim 6 Column 15 Line 19 After --to-- insert --be activated-n Claim 6 Column 15 Line 20 Delete --deactivated--.

Claim 21 Column 17 Line 12 After --referenceinsert -signals defining an allowable synchronizing signal range and--.

Signed and Sealed this second Day Of September 1975 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer ('mnmissiuner 0f Patents and Trademarks

Claims

1. Apparatus for sterlizing liquid filled ampoules comprising a microwave heating chamber, conveying means for moving said ampoules through said chamber, means for producing a temperature signal indicative of the temperature of each ampoule passed through said chamber, a check circuit means for comparing said temperature signal with reference signals which define an allowable temperature signal range and for generating a reject signal when said temperature signal is outside of the allowable temperature signal range, and an ampoule sorter means which is responsive to the reject signal for rejecting ampoules.

4. Apparatus for sterilizing liquid filled ampoules comprising a microwave heating chamber, a conveying means for rolling said ampoules through said chamber, a black body reference maintained at a constant temperature, and a control system comprising a radiation pyrometer means for alternately producing a first temperature signal indicative of the temperature of each ampoule passed through said chamber and a second temperature signal indicative of the temperature of said black body reference, a first means for comparing the first temperature signal with a first set of reference signals defining an allowable first temperature signal range and for generating a first reject signal when said first temperature signal is now in the allowable first temperature signal range, and a second means for comparing the second temperature signal with a second set of reference signals defining an allowable second temperature signal range and for generating a second reject signal when said second temperature signal is not within the allowable second temperature signal range and at least one ampoule sorter means for rejecting ampoules, which is responsive to either the first or second or bOth reject signals and is positioned adjacent said conveying means and spaced downstream from said pyrometer means.

11. Apparatus according to claim 4 comprising a means for independently producing a third temperature signal indicative of the temperature of the black body reference and a third means for comparing said third temperature signal with a third set of reference signals defining an allowable third temperature signal range and for generating a third reject signal when said third temperature signal is not within the allowable third temperature signal range, and wherein said ampoule sorter means is also responsive to said third reject signal.

12. Apparatus according to claim 11 wherein said third means for comparing and generating said third reject signal comprises a means for comparing the third temperature signal with an upper limit reference signal, means for comparing the third temperature signal with a lower limit reference signal and a logic circuit means for generating reject signals.

14. Apparatus according to claim 13 wherein said second signal processing logic circuit means activates said sorter means to reject at least one ampoule that has passed the pyrometer means prior to the reject signals and maintains said sorter means activated to reject at least one ampoule that had not reached the pyrometer means after the discontinuation of said first, second or third reject signals.

15. Apparatus according to claim 11 comprising a power source means for supplying power to at least part of said control system, a fourth means for comparing the power of said power source means with reference signals defining an allowable power range and for generating a fourth reject signal when said power is not within the allowable power range and wherein the ampoule sorter means is also responsive to the fourth reject signal.

17. Apparatus according to claim 15 comprising a first signal processing logic circuit means for receiving the first reject signals indicative of out-of-temperature ampoules and at some time later causing the sorter means spaced along the conveying means downstream from the pyrometer means to be activated when said out-of-temperature ampoules are thereat, and comprising a second signal processing logic circuit means for receiving the second, third and fourth defect signals and for activating said sorter means to reject any ampoule that was adjacent the pyrometer means at the time said second, third, or fourth reject signals were generated.

18. Apparatus according to claim 17 wherein said second signal processing logic circuit means activates said sorter means to reject at least one ampoule that had passed the pyrometer means prior to the reject signals and maintains said sorter means activated to reject at least one ampoule that had not reached the pyrometer means after the discontinuation of said first, second, third or fourth reject signals.

19. Apparatus according to claim 12 comprising a means for generating a first synchronizing signal coincident with the production of said first temperature signal indicative of each ampoule temperature, said first means for comparing and generating sid first reject signal being responsive to said first synchronizing signal.

22. Apparatus according to claim 21 comprising a first signal processing logic circuit means for receiving the first reject signals indicative of out-of-temperature ampoules and at sometime later causing the sorter means spaced along the conveying means downstream from the pyrometer means to be activated when said out-of-temperature ampoules are thereat and comprising a second signal processing logic circuit means for receiving said second, third, fourth and fifth defect signals and for activating said sorter means to reject at least any ampoule that was adjacent the pyrometer meAns at the time said second, third, fourth or fifth defect signals were generated.