WO1998046135A1

WO1998046135A1 - Security system for detecting movements

Info

Publication number: WO1998046135A1
Application number: PCT/CA1997/000247
Authority: WO
Inventors: Claude Bergeron; Daniel Guay; Guylain Prince; Eric Tremblay; Laurent Chabot; Isabelle Proulx; Allens Tremblay; Dany Tremblay
Original assignee: Géni Médic Inc.
Priority date: 1997-04-14
Filing date: 1997-04-14
Publication date: 1998-10-22
Also published as: AU2284897A

Abstract

A security system (10) for detecting unauthorized movements of persons is described herein. The security system (10) includes at least one detection unit (12, 14) that may be linked to a conventional hospital call system (38) to indicate to the hospital staff that unauthorized movements are detected in a particular room. The detection unit (12, 14) includes a sensing element (42) and an electronic circuit (44) generating an alarm if the sensor detects movements for a predetermined duration. The security system may also include a security cover (16) to prevent a person lying on a bed (18) from falling from the bed. When it is the case, the sensing element is placed so that only from the bed. When it is the case, the sensing element is placed so that only the headboard portion of the bed is monitored. The security system may also include a RF transmitter (312) to transmit the alarm signal to a pager (324).

Description

TITLE OF THE INVENTION

Security system for detecting movements

FIELD OF THE INVENTION

The present invention relates to security systems for detecting the movements of persons.

BACKGROUND OF THE INVENTION

In hospitals, nursing homes and the like, it is widely known that it may become necessary, for various reasons, to use a system for detecting and/or preventing the movements of persons.

For example, if a patient is agitated in his sleep or if a patient becomes aggressive, that person may fall off the bed and cause himself serious injuries.

When conventional hospital bed side rails are not sufficient to reasonably insure the hospital staff that the patient is safe, the hospital staff have resorted to restraining patients by attaching their wrists and ankles to the side rails using specially designed restraint straps. While this procedure will generally prevent the patient from falling off the bed, it also has many disadvantage. Firstly, it is not visually pleasing, for example for visiting loved ones, to see a patient physically restrained to a bed. Secondly, the patient may become uncomfortable and will be unable to change his position on the bed, resulting in perhaps long periods of discomfort and perhaps bruising of the patient and may leave physical and psychological after-effects. Thirdly, the restraint straps used to attach the wrists and ankles of the patient are generally difficult to clean. Finally, the extent of time and effort necessary for hospital staff to install and remove the physical restraints is also a disadvantage.

In a copending United States Patent application entitled "Security Cover" the applicant has designed a security cover that may easily be installed to a hospital bed for preventing a patient to fall off the bed. Indeed, the security cover described in this patent application creates an enclosed space around the person lying on the bed thereby preventing the person from falling off the bed.

While the security cover described in this application is adequate to prevent people from falling off beds, it does not cover the headboard portion of the bed so as to prevent a patient from crawling from under the security cover. If this is the case, the patient may then fall off the bed.

OBJECTS OF THE INVENTION

An object of the present invention is therefore to provide an improved security system for indication movements.

Another object of the invention is to provide a security system that may be used with a security cover to greatly reduce the risks of patient falls from bed. SUMMARY OF THE INVENTION

More specifically, in accordance with the present invention, there is provided a security system for indicating movements of a person within a predetermined area; the security system being connectable to a room panel of a conventional call system and comprising: a detection unit to be connected to the room panel; the detection unit including: at least one sensing element for detecting movements indicating that the person is trying to move in an unauthorized direction; means for controlling the sensing element; the controlling means including a discrimination system responsive to the detection of movements by the sensing means to generate an alarm signal when predetermined conditions have been met; wherein the alarm signal is supplied to the conventional call system to indicate that movements have been detected.

According to another aspect of the present invention, there is provided a security system for indicating movements of a person; the security system comprising: a detection unit including: at least one sensing element for detecting movements indicating that the person is trying to move in an unauthorized direction; means for controlling the sensing element; the controlling means including a discrimination system responsive to the detection of movements by the sensing means to generate an alarm signal when predetermined conditions have been met; and means for transmitting the alarm signal; and a reception unit including: means for receiving the alarm signal; wherein the alarm signal is transmitted from the detection unit to the reception unit to indicate that movements have been detected.

According to yet another aspect of the present invention, there is provided a security system for preventing a person lying on a bed from falling off the bed and for indicating movements of the person, the security system being connectable to a room panel of a conventional call system, the bed being the type having a mattress mounted on a mattress support, the mattress support including two opposite longitudinal sides, a footboard portion and a headboard portion, the security system comprising: a security cover; cooperating securing means on the cover and the mattress support, wherein the cover may be releasably mounted to the mattress support to thereby form, with the mattress, an enclosed space around the person lying on the bed thereby preventing the person from falling off the bed; a detection unit to be connected to the room panel; the detection unit including: at least one sensing element for detecting movements indicating that the person is trying to move in an unauthorized direction; means for controlling the sensing element; the controlling means including a discrimination system responsive to the detection of movements by the sensing means to generate an alarm signal when predetermined conditions have been met; wherein the alarm signal is supplied to the conventional call system to indicate that movements have been detected.

In the present description and in the appended claims, the term "call system" is to be generally construed as a system used to transfer information from a plurality of remote locations to a central location. For example, in an hospital, to transfer information from a plurality of room communication panels to a central nurse station.

Other objects, advantages and features of the present invention will become more apparent upon reading of the following non restrictive description of preferred embodiments thereof, given by way of example only with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the appended drawings: Figure 1 is a perspective view of a security system according to a first embodiment of the present invention, the security system includes a pair detection unit connectable to a hospital call system and a security cover;

Figure 2 is a perspective view of one of the detection unit of Figure 1 ;

Figure 3 is a block diagram of one of the detection unit of Figure 1 ;

Figure 4 is a perspective view of a security system according to a second embodiment of the present invention, the security system including a detection unit connectable to a hospital call system;

Figure 5 is a block diagram of a security system according to a third embodiment of the present invention, the security system including a detection unit and a reception unit;

Figure 6 is a block diagram of a security system according to a fourth embodiment of the present invention, the security system including a plurality of detection units and a reception unit;

Figure 7 is a block diagram of a security system according to a fifth embodiment of the present invention, the security system including a detection unit and a reception unit; and Figure 8 is a flow diagram illustrating the general operation of the detection units of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Figure 1 of the appended drawings illustrates a security system 10 according to a first embodiment of the present invention. The security system 10 includes first and second detection unit 12 and 14 and a security cover 16.

The security cover 16 is mounted to a bed 18 provided with a mattress support 20, a headboard 22 and a mattress 24. The security cover 16 creates an enclosed space around a person (not shown) lying on the mattress 24 to help prevent the fall of this person from the bed.

The security cover 16 includes a first securing assembly 26 mounted to the foot portion of the mattress support 20 and a second securing assembly 28 mounted to the headboard portion of the mattress support 20. Two bands of elastically deformable material 30 (only one shown) are removably attached, through securing elements 31 , to the first and second securing assemblies 26 and 28 on either sides of the mattress support 20. A third band of elastically deformable material 32 is removably attached along the second securing assembly 28 through securing elements 33 (only one shown). A cover 34, advantageously made of durable material, is provided with a plurality of loops 36 on three sides. The loops 36 may be inserted on the bands of elastically deformable material to thereby retain the cover 34 onto the mattress 24 to form the enclosed space discussed above.

The security cover 16 therefore efficiently prevents a person lying on the mattress 24 from falling on the floor while being simple to install over the person though the removable securing elements 31 and 33.

The first and second detection units 12 and 14 are used to generate and alarm signal when they detect an object in their detection field. By providing detection units having short detection fields not extending below the horizontal, only the movements of the person lying on the mattress 24 will be detected if they are at or near the level of the detection units 12 or 14. If the patient lying on the mattress 24 is trying to get off the bed, the detection field of at least one of the detection units will be crossed and the alarm signal will be generated. The detection units 12 and 14 therefore define an unauthorized direction in which no movements longer than a predetermined duration, as will be described hereinafter, are allowed.

Since the detection units 12 and 14 are serially interconnected and electrically connected to a hospital call system 38, the alarm signal may be directed to a central nurse station where it will be processed to dispatch appropriate personnel to help the patient.

Turning now to Figures 2 and 3 the detection units 12 and 14 will be described in greater details. It is to be noted that only detection unit 12 will be described since detection units 12 and 14 are similar.

The detection unit 12 includes a housing 40, a sensor 42, an electronic circuit 44, controls 46, an output jack 48 and a bypass jack 49. The controls 46 are all electrically connected to the electronic circuit 44 and include an off switch 50, a mechanical/electrical operation selector 52, an indication led 54 and a sensibility adjustment button 56.

As can be seen from Figure 1 , the housing 40 may be mounted to the headboard 22 of a hospital bed.

As discussed hereinabove, the sensor 42 is advantageously a sensor having a short sensing field so that only movements close to the sensor 42 are detected. It has been found that the photoelectric sensor model number E3JU-D1 , made by the OMRON Corporation, and using a diffuse reflective method of detection is adequate to sense only the motions happening in the vicinity of the sensor.

As will be easily understood by one of ordinary skills in the art, the electronic circuit 44 may be analog and/or digital and may include microcontrollers and the like. Since the type of circuit used to produce the desired results is highly dependent on the designer and since the design of such a circuit is believed to be known in the art, this circuit will not be further discussed herein. Since some hospitals still use older mechanical type call systems and some hospitals use newer electrical call systems, a mechanical/electrical operation selector 52 has been provided to allow the detection unit 12 to communicate with both call system types.

The sensibility adjustment button 56 is provided to adjust the maximum detection duration before generating the alarm signal. Indeed, it would not be practical to generate an alarm signal each time a short duration movement is detected be the sensor 42 since the detection unit 12 is intended to detect the patient trying to get out his bed. It is therefore possible to adjust the maximum duration of positive detection before an alarm signal is generated. The electronic circuit 44 therefore acts as a variable discriminator to generate an alarm signal only when the time duration condition is met. For example, the duration range of the sensibility adjustment button 56 could be from 0 to 10 seconds.

The output jack 48 is used to link the detection unit 12 to the call system 38 through an electrical cable 58 (Figure 1). The cable 58 links the output jack 48 to an input 60 of the call system usually used to allow patient to call for a nurse via a manual switch 61 (Figure 1).

The bypass jack 49 is used to link a second detection unit (for example unit 14) to the detection unit 12. Therefore, if the detection unit 14 generates an alarm signal, this signal will be supplied to the call system 38 via the detection unit 12. In Figure 1 , the detection unit 14 is linked to the detection unit 12 via an electrical cable 59. The bypass jack 49 is also used to link the manual switch 61 to the detection unit so as to allow normal operation of the manual switch 61. The general operation of the detection unit 12 is illustrated in the flow diagram of Figure 8. After the system is started (step 100) an initialization step is performed by which a counter T is reset (step 102). In step 104 a test is performed to determine if the sensor 42 detects an object. If this is not the case the counter T is reset (step 106) and the system is returned to step 104. If an object is detected in step 104, the counter T is incremented (step 108) and a second test is performed (step 110) to determine if the counter T is greater that a reference (REF) adjusted through the button 56 (Figure 2). If this is not the case, the system is returned to the step 104. If the counter T is greater than REF, an alarm signal is generated (step 112).

Turning now to Figure 4, a security system 300 according to a second embodiment of the present invention will be described. The major differences between the security system 10 of Figure 1 and the security system 200 is that the security system 200 includes only one detection unit 202 and does not include a security cover.

The detection unit 202 is mounted to a support 204, including a foot portion 205, and includes a sensor portion 206 and an electronic portion 208. The sensor portion includes a sensor element 210, similar to sensor 42 (Figure 1-3), mounted at a distal end of a flexible tube 212. As can be seen from this figure, the electronic portion 208 includes the controls 214, similar to controls 46 of Figure 2, an output jack 216 and a bypass jack 217. The operation and the connection of the detection unit 202 to the call system 218 are similar to the operation and to the connection of the detection units 12 and 14 illustrated in Figures 1-3.

It is to be noted that if more than one detection units 200 are used, the detection units may be serially linked through the bypass jack 217. Also, a more convenient location of the bypass jack 217' on the foot portion 205 of the support 204 is illustrated in Figure 4.

The security system 200 is advantageously used to define a direction of unauthorized movements other than over a hospital bed. For example, if an elderly person is sitting on a chair, it may be advantageous to place the sensor portion 206 so that the alarm signal will be generated if the person gets up from the chair, to thereby notify the hospital staff. Of course, more than one detection unit could be used to create a perimeter around the patient.

Similarly, the security system 200 could be used besides a child crib to detect the movements of the child trying to egress the crib.

Figure 5 of the appended drawings is a block diagram of a security system 300 according to a third embodiment of the present invention. The security system 300 includes a detection unit 302 and a reception unit 304.

The major difference between the security system 300 and the security systems 10 and 200 is that the security system 300 does not require a conventional call system for its operation. The detection unit 302 includes a sensor 306, an electronic circuit 308 and controls 310, similar to their respective counterparts 42, 44 and 46 of Figure 3. The detection unit 302 also includes a radio-frequency (RF) transmitter 312 coupled to a RF antenna 314.

The reception unit 304 includes a receiving antenna 316 coupled to a RF receiver 318, an electronic circuit 320 and a modem circuit 322. The modem circuit 322 may enter in communication with a plurality of pager units 324 (only one shown) through a telephonic line

326.

The general operation of the security system 300 will now be described. When an alarm signal is generated by the electronic circuit 308, it is encoded and transmitted by the RF transmitter 312 through the antenna 314. This encoded alarm signal is received by the RF receiver 318 and decoded by the electronic circuit 320. The electronic circuit 320 then determine which pager 324 must be activated and which code is to be displayed onto the pager 324 to indicate the nature of the alarm to the user of this pager. This information is supplied to the modem circuit 322 to be acted upon.

Of course, as will be apparent to one of ordinary skills in the art, the antenna 316, the RF receiver 318, the electronic circuit 329 and the modem circuit 322 could be different pieces of equipment interconnected or could be designed in a single electronic circuit (not shown). Figure 6 is a block diagram illustrating a security system 400 according to a fourth embodiment of the present invention. The major difference between the security system 400 and the security system 300 is that the detection unit 401 of the security system 400 includes a plurality of sensors 402, 404 and 406, each provided with respective electronic circuits 408, 410 and 412 and controls 414, 416 and 418.

The electronic circuits 408, 410 and 412 are connected to a controller circuit 420 encoding the alarm signals before their transmission through a RF transmitter 422 as described hereinabove with reference to Figure 5.

The security system 400 is advantageous if multiple sensors are required.

Of course, the electronic circuits 408, 410 and 412 and the controls 414, 416 and 418 could be integrated with the controller circuit 420.

It is to be noted that the controller circuit 420 could also act as a discriminator. Indeed, it is within the reach of one skilled in the art to design a controller circuit 420 to supply the alarm signal to the RF transmitter 422 only if predetermined conditions are met, for example, one such condition could be that two sensors detect movement at the same time, or that a particular sequence of movement detection by the sensors is detected. Turning now to Figure 7 a security system 500 according to a fifth embodiment of the present invention will not be described. The major difference between the security system 500 and the security systems 300 and 400 is that the detection unit 502 of the security system 500 directly transmits the alarm signal to a pager 504.

The security system 500 is particularly advantageous for personal use, for example for a person keeping an elderly relative at home and requiring one or a few detection units 502 to relay alarm signals to a pager unit 504.

The electronic circuit 506 of the detection unit 502 encodes the alarm signal so that it is in a format adapted to be transmitted to the pager 504 through a transmitter 508.

The controls of the detection units 302, 401 and 502 of Figure 5 to 7 are slightly different from the controls 46 and 204 illustrated in Figures 2 and 4. Indeed, the mechanical/electrical operation selector 52 is no longer necessary.

Although the present invention has been described hereinabove by way of preferred embodiments thereof, it can be modified, without departing from the spirit and nature of the subject invention as defined in the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A security system for indicating movements of a person within a predetermined area; the security system being connectable to a room panel of a conventional call system and comprising: a detection unit to be connected to the room panel; said detection unit including: at least one sensing element for detecting movements indicating that the person is trying to move in an unauthorized direction; means for controlling said at least one sensing element; said controlling means including a discrimination system responsive to the detection of movements by said at least one sensing means to generate an alarm signal when predetermined conditions have been met; wherein said alarm signal is supplied to the conventional call system to indicate that movements have been detected.

2. A security system as recited in claim 1 , wherein said predetermined conditions include a minimum duration of the movement detection by said at least one sensing element.

3. A security system as recited in claim 2, wherein said controlling means include means for adjusting said minimum duration.

4. A security system as recited in claim 1 , wherein said controlling means include an electronic circuit.

5. A security system as recited in claim 1 , wherein said at least one sensing element include a photoelectric sensor.

6. A security system for indicating movements of a person; the security system comprising: a detection unit including: at least one sensing element for detecting movements indicating that the person is trying to move in an unauthorized direction; means for controlling said at least one sensing element; said controlling means including a discrimination system responsive to the detection of movements by said at least one sensing means to generate an alarm signal when predetermined conditions have been met; and means for transmitting said alarm signal; and a reception unit including: means for receiving said alarm signal; wherein said alarm signal is transmitted from said detection unit to said reception unit to indicate that movements have been detected.

7. A security system as recited in claim 6, wherein said predetermined conditions include a minimum duration of the movement detection by said at least one sensing element.

8. A security system as recited in claim 7, wherein said controlling means include means for adjusting said minimum duration.

9. A security system as recited in claim 6, wherein said controlling means include an electronic circuit.

10. A security system as recited in claim 6, wherein said at least one sensing element include a photoelectric sensor.

11. A security system as recited in claim 6, wherein said transmitting means include a RF transmitter and wherein said receiving means include a RF receiver.

12. A security system as recited in claim 11 , wherein said reception unit also includes means for transmitting a coded signal representative of the alarm signal to a pager unit through a telephone link.

13. A security system for preventing a person lying on a bed from falling off said bed and for indicating movements of the person, said security system being connectable to a room panel of a conventional call system, said bed being the type having a mattress mounted on a mattress support, said mattress support including two opposite longitudinal sides, a footboard portion and a headboard portion, said security system comprising: a security cover; cooperating securing means on said cover and said mattress support, wherein said cover may be releasably mounted to said mattress support to thereby form, with said mattress, an enclosed space around said person lying on said bed thereby preventing the person from falling off said bed; a detection unit to be connected to the room panel; said detection unit including: at least one sensing element for detecting movements indicating that the person is trying to move in an unauthorized direction; means for controlling said at least one sensing element; said controlling means including a discrimination system responsive to the detection of movements by said at least one sensing means to generate an alarm signal when predetermined conditions have been met; wherein said alarm signal is supplied to the conventional call system to indicate that movements have been detected.

14. A security system as recited in claim 13, wherein said predetermined conditions include a minimum duration of the movement detection by said at least one sensing element.

15. A security system as recited in claim 14, wherein said controlling means include means for adjusting said minimum duration.

16. A security system as recited in claim 13, wherein said controlling means include an electronic circuit.

17. A security system as recited in claim 13, wherein said at least one sensing element include a photoelectric sensor.

18. A security system as recited in claim 13, wherein said transmitting means include a RF transmitter and wherein said receiving means include a RF receiver.

19. A security system as recited in claim 18, wherein said reception unit also includes means for transmitting a coded signal representative of the alarm signal to a pager unit through a telephone link.