DE1263189B - Circuit arrangement with a vibrating tongue contact - Google Patents

Description

Circuit arrangement with a single oscillating tongue contact Known remote control devices use sections of a public supply network as a telecontrol channel electrical power. The telecontrol signals are the mains voltage, which is here in the Usually an alternating voltage is superimposed in the form of audio frequency pulses. the The audio frequency pulses are generated in some known telecontrol devices with the help of an electrical oscillating circuit, which is controlled by a tactile contact in a certain rhythm and in a certain relation to the phase position of the mains alternating voltage is connected to the power supply network. Each time it is switched on, it arises a damped oscillation of the electrical resonant circuit, which is on a suitable Audio frequency is tuned.

To achieve a high audio frequency energy per audio frequency pulse It is known that it is necessary that the electrical resonant circuit at the time a peak value of the auxiliary AC voltage is connected to this and .that the shutdown also takes place at a mains voltage peak value, which however has an opposite sign than that applied at the time of connection. This gives the capacitor of the electrical oscillating circuit its largest possible Charging compared to the instantaneous value of the mains alternating voltage prevailing at the time of connection.

In order to achieve simple designs that are mass-produced can be produced, contact devices are preferably used as pushbutton switches with a vibrating tongue that is connected to the .the with the AC voltage to be superimposed on the audio frequency pulses appropriately closed Electromagnet is excited to vibrate, with each vibration of the vibrating tongue a push button contact, is closed. Such contact devices are manifold Problems arise, on the one hand because of the relatively high contact load, on the other hand because of the considerable noise generated with the use of vibrating tongue contacts connected is. .In addition, the observance. Of a certain switch-on ratio requires this is the ratio of the time within a period of oscillation of the vibrating tongue, during which the push button contact is closed, for the duration of its open State within the same period of oscillation, special mechanical measures .at the contact device if the audio frequency pulses have a high energy content should be achieved.

To solve the problem posed by the problems presented is in the following a combination of mechanical and electrical means is provided, whereby use is made of the known possibility, the free spring length a contact spring with increasing deflection of the same due to progressive pressure to shorten the contact spring on a contact arm with a certain curve shape, to counteract the tendency of switching contacts to bounce.

A circuit arrangement with a vibrating tongue contact, which is in series is connected to an AC voltage network with an electrical oscillating circuit, .that at the same time as a voltage source for -feeding a vibrating tongue with a contact element of the vibrating tongue contact to form vibrations-stimulating electromagnets serves, is .dem according to the invention characterized in that the in itself known way a permanently magnetized oscillating mass carrying oscillating tongue on a fixed, curved stop in the resting state under slight pretension and at the same time: the stop curve as a tangent at least approximately at the attachment point of the contact element touches, and that the vibrating tongue contact is a diode electrically is connected in parallel.

For details of the circuit configuration defined here, see from the following description of an exemplary embodiment on tape of the drawing, that have a contact device with vibratory tongue contact in a circuit arrangement show. In the drawing figure 1 and 2 denote terminals, to an alternating voltage network, for example to a phase conductor and the neutral conductor of the same, are connected. The electrical series circuit is located in a main current path 3 one consisting of a capacitor 4 and a choke coil 5 electrical Resonant circuit 6 with a vibrating tongue contact 7. The vibrating tongue contact 7 is electrically bridged by a diode 8. One immediately after the terminals The secondary current path 9 branched off 1 and 2 contains the excitation winding 10 of an electromagnet 11 with a core 12. A switch 13 is used to switch on the auxiliary current path 9.

The core 12 of the electromagnet 11 is attached to a support frame 14, which also has an oscillating tongue 17 as well as insulating spacers 15 and 16 a curved stop 18 carries. The stop 18 is via fasteners 19 and 20 with the support frame 14 and the oscillating tongue 17 at a clamping point 20 rigidly connected.

The oscillating tongue 17 has at its opposite the clamping point 20 Ends a preferably permanently magnetically polarized, d. H. as a permanent magnet trained oscillating mass 21. In addition, there is a contact element on the oscillating tongue 17 22 of the vibrating tongue contact 7 attached, while a contact piece 23 of the vibrating tongue contact 7 is held by a bracket 24, which in turn with the support frame 14 in solid Connection. The contact distance of the vibrating tongue contact 7, that is the distance of the contact element 22 from the contact piece 23 when the oscillating tongue 17 is at rest, is only a few tenths of a millimeter, preferably 0.2 to 0.3 mm.

By suitable fastening and shaping of the stop 18 and. the oscillating tongue 17 is achieved that the oscillating tongue 17 is below in the rest state slight bias is applied to a stop curve 25 of the stop 18 in such a way that that they have a point of contact near the attachment point of the contact element 22 forms a tangent to the stop curve 25: A correct choice of the contact distance as well as the position of the point of contact, or rather the line of contact, between the resting oscillating tongue 17 and the stop curve 18 is for the switching behavior the 'vibrating tongue contact is of the utmost importance.

The stop curve 25 has at least the point of contact with the resting oscillating tongue 17 from towards its free end towards a circular arc shape. This curve shape is not only easy to manufacture but has also proven to be beneficial for the way it works of the vibration system. That does not mean, however, that not others too geometric shapes of the stop curve 25 lead to favorable results.

As a rule, the contact element 22 has on the opposite side of the tongue spring 17 a fastener, e.g. B. a rivet head or the like. It is now appropriate to provide a recess in the stop 18 in which this rivet head can be accommodated, so that the tongue spring 17 actually at the attachment location of the contact element 22 can rest smoothly on the stop curve 25.

The oscillating mass 21 of the oscillating tongue 17 is preferably magnetic in this way polarized that the magnetic main axis in the direction of oscillation of the vibrating tongue 17 shows, d. H. So that in the representation chosen in the drawing figure the north pole is on top and the south pole is on the bottom or vice versa. With this magnetic The orientation of the oscillating mass 21 corresponds to that shown in the drawing Pole arrangement of the electromagnet 11.

As a permanent magnet material for the oscillating mass 21, it is advantageous ceramic magnetic material or synthetic resin-bonded permanent magnet powder is used. For manufacturing reasons, it can be advantageous to use the oscillating mass 21 in the manner evident from the drawing figure on one side of the oscillating tongue 17 to be attached, for example by angled parts of the swing tongue Adhesive or the like when using synthetic resin-bonded powder magnet materials however, it is also possible to attach the oscillating mass 21 directly to the oscillating tongue 17 to be cast on, which of course is also symmetrical to the oscillating tongue 17 can be arranged.

Finally, it is possible to use the oscillating mass 21 during manufacture the vibrating tongue 17 to this from the material used for the vibrating tongue to be formed, provided that the material can be polarized with permanent magnets.

To the oscillation of the vibrating tongue 17 in the force field of the electromagnet 11 can favor the neutral zone between the poles of the electromagnet 11 opposite the magnetically neutral zone of the oscillating mass 21 in the direction of oscillation of the oscillating tongue 17 are at most arranged asymmetrically offset, preferably in the direction of oscillation against the stop 18, ie upwards in the figure.

With one-sided attachment of the oscillating mass 21 to the oscillating tongue 17 arises in the arrangement shown in the figure as a result of the magnetic Attraction forces anyway a slight deformation of the oscillating tongue 17 at rest, in such a way that the pole of the oscillating mass which is further away from the oscillating tongue 17 21 approximates somewhat to the opposite pole leg of the electromagnet 11. In this way, there is also an asymmetry of the permanent magnetic field, which favors the oscillation.

To simplify the following description of the mode of operation the circuit arrangement is based on the assumption that the frequency of the terminals 1 and 2 applied mains AC voltage is 50 Hz. The same considerations as for 50 Hz, of course, also apply accordingly to 60 Hz and to any other Grid frequency.

The coordination of the oscillating tongue 17 and oscillating mass 21 formed vibratory system is selected, for example, such that the Oscillation duration of a period of the oscillating tongue oscillation is twice as long as the oscillation period of a period when the switch 13 is closed on the excitation winding 10 of the electromagnet 11 applied mains AC voltage. The period of oscillation the vibrating tongue 17 is in this example 40 milliseconds, its natural frequency hence 25 Hz; it is therefore in subharmonic resonance to the network frequency. Of course, other votes of the vibratory System conceivable, for example in such a way that its natural frequency is a harmonic to the frequency of the AC line voltage exciting the electromagnet 11.

In that half oscillation of the oscillatory system in which when the oscillating tongue 17 approaches the stop curve 25, the effective spring length becomes the vibrating tongue 17 is continuously shortened as a function of the amplitude of its oscillation and thus the spring constant of the oscillating tongue 17 progressively increases, which is in a shortening of the period of oscillation during this half oscillation. In the opposite half oscillation of the vibrating tongue contact 7 is because of its very small contact distance after a relatively small oscillation path of the Swing tongue 17 closed and then almost for the full duration of the free Half oscillation of the vibrating tongue 17 held in the closed state.

Because now both half-oscillations of a period of the oscillatable Systems are of unequal length, can be done without using suitable mechanical coordination Difficulty achieve that the vibrating tongue contact 7 is exactly one time half a period of the vibrating tongue or at most less than a quarter period the same is closed longer, in the example preferably for 20 milliseconds, which corresponds to the duration of one period of the 50 Hz AC mains voltage. By @ simple, mechanical or electrical phase alignment taking place in a known manner now a temporal coincidence of the times of closing and opening of the vibrating tongue contact 7 is set with the occurrence of peak values of the AC mains voltage of the same name. Thus, the vibrating tongue contact 7 closes and opens alternately with successive Mains voltage maxima of the same polarity, for example at the peak values of the positive mains voltage half-waves as long as the switch 13 is closed.

The diode 8 should be polarized so that they are half-waves at all of those the voltage of the alternating voltage network is conductive, which is an opposite Have polarity like the mains voltage half-waves, in which an opening or closing the vibrating tongue contact takes place, so z. B. during the appearance of the negative Mains voltage half-waves. The diode 8 thus once causes a current discharge of the Vibrating tongue contact 7 within the period during which the vibrating tongue contact 7 is closed and the diode 8 is conductive, on the other hand a charging of the capacitor 4 to the negative peak value of the mains AC voltage in the period in which the vibrating tongue contact 7 is open.

Due to the described training and coordination of the parts of the The circuit arrangement results each time the vibrating tongue contact 7 is closed at the capacitor 4 a charge reversal surge with the largest possible in this circuit arrangement Amplitude. The oscillating circuit 6 becomes damped oscillations as a result of this recharging current surge excited in its natural frequency, which is preferably in the audio frequency range, z. B. is between 400 and 600 Hz. These audio frequency oscillations now run as intended as remote control signals via the terminals 1, 2 in the power supply network a. Above it was mentioned that the oscillating tongue 17 in its rest state with A slight pretension should be applied to the stop 18. This has the advantage of that inadvertently acting on the vibrating tongue 17 vibrations or magnetic External fields cannot easily excite them to vibrations, which lead to a closing of the vibrating tongue contact 7.

By using the curved stop 1.8 is a for the timing of the position of the switch-on and switch-off points of the vibrating tongue contact 7 required asymmetry of the required relative to the time curve of the AC mains voltage reached two half-waves of the vibrating tongue without this being a significant The result would be an increase in the generation of noise, because the oscillating tongue 17 moves steadily and therefore “softly” applied to the stop curve 25. It also causes the curvilinear Stop 18 significantly flattens the bending stresses in the vibrating tongue 17 in the passive half-wave, i.e. as it approaches the stop curve 25, in particular in the area of the attachment location of the contact element 22.

The chosen arrangement of the vibrating tongues also has the advantage that the natural frequency of oscillation of the oscillating tongue 17 is only used during manufacture the same need not be adhered to very precisely because the period of oscillation the oscillating tongue 17 can also influence the geometry of the stop curve 25 can, which results in a very convenient adjustment by the stop 18 is slightly bent by known adjusting means, if the manufacturing tolerances make a slight readjustment necessary. The oscillating mass 21 also exists made of synthetic resin-bonded magnetic material, because of its ease of processing Another very simple adjustment option by removing substance from the oscillating mass 21, for example by scraping or filing.

The arrangement of the diode 8 electrically parallel to the vibrating tongue contact 7 is achieved without mechanical complication of the vibrating tongue device that the connection of the resonant circuit 6 always with the greatest possible voltage difference takes place at the capacitor 4. Therefore the energy content is that described with the Circuit arrangement generated audio frequency pulses particularly large.

From the circuit arrangement shown in the drawing figure to recognize that a sequence of audio frequency pulses is generated as long as the switch 13 is closed. The circuit arrangement described represents in its entirety with vibrating tongue contact is a particularly simple transmission device, as it is for example be arranged at numerous consumption measuring locations in a power supply network can to transmit energy consumption information to a central control point. Within a query system for consumption meters to record individual consumption For example, the switches 13 of the circuit arrangements are used for public consumer goods closed by remote control commands in a specific time sequence and thus causing the transmitting devices to emit audio frequency pulses. the The manner in which information is encrypted in such broadcasting devices and how they are evaluated are known.

Claims (7)

Claims: 1. Circuit arrangement with a vibrating tongue contact, which is connected in series with an electrical oscillating circuit to an AC voltage network is that at the same time as a voltage source for supplying a vibrating tongue with a contact element of the vibrating tongue contact to form vibrations-stimulating electromagnets serves, thereby g e k e n nz e i c h n e t that the in a known manner a permanently magnetized oscillating mass (21) carrying oscillating tongue (17) on a stationary one curved stop (18) is applied in the rest state under slight bias and a stop curve (25) as a tangent at least approximately at the attachment point of the contact element (22) touches, and that the vibrating tongue contact (7) a diode (8) is electrically connected in parallel. 2. A circuit arrangement according to claim 1, characterized in that the stop (18) which: is rigidly connected oscillating tongue (17) at a clamping point (20). 3. Circuit arrangement according to claim 1, characterized in that the contact element (22) is opposite a contact piece (23) held by a bracket (24 ) at a contact distance of 0.2 to 0.3 mm and the bracket (24) with a support frame (14) is rigidly connected. 4. Circuit arrangement according to claim 1, characterized in that the stop curve (25) has a green arch shape. 5. Circuit arrangement according to claim 1 or 2, characterized in that a recess is provided in the stop (18) in softer there is space for a fastening element of the contact element (22). 6. Circuit arrangement according to claim 1, characterized in that the oscillating mass (21) is made of ceramic Permanent magnet material. 7. Circuit arrangement according to claim 1, characterized in that the oscillating mass (21) consists of Kunsthaxzgebundenem permanent magnet powder. Circuit arrangement according to Claims 1, 6 and 7, characterized in that the oscillating mass (21) is attached to one side of the oscillating tongue (1-7) by angled parts thereof. 9. Circuit arrangement according to claim 7, characterized in that the oscillating mass (21) is cast onto the oscillating tongue (17). 10. Circuit arrangement according to claim 1; characterized in that the oscillating mass (21) is molded onto the oscillating tongue (17) from the material of the oscillating tongue. 11. Circuit arrangement according spoke 1, characterized in that the oscillating tongue (17) is tuned to subharmonic resonance to the frequency of the AC voltage network. 12. Circuit arrangement according to claim 11, characterized in that the natural frequency of the oscillating tongue (17) is half as large as the frequency of the AC voltage network. 13, circuit arrangement according to claims 1, 11 and 12, characterized in that the vibrating tongue contact (7) is closed during a period of the vibrating tongue oscillation for exactly half the duration of this period. 14. Circuit arrangement according to claims 3, 11, 12 and 13, characterized in that the times of opening and closing of the .Schwingzungenkontaktes (7) are coincident with the occurrence of peaks of the same name of the voltage of the AC network. 15. Circuit arrangement according to claim 14, characterized in that the diode (8) is polarized so that ß it is conductive at all those half-waves of the voltage of the AC voltage network, which have an opposite polarity than the mains voltage half-waves in which opening or closing .des Vibratory tongue contact (7) takes place. 16. Circuit arrangement according to claim 1, characterized in that the natural frequency is a harmonic to the frequency of the AC voltage network. 17. Circuit arrangement according to claims 1 to 16, characterized by its use as a transmitting device for generating audio frequency pulses in telecontrol devices, in particular in query systems for consumption meters for recording the individual consumption of public consumer goods. References Considered: U.S. Patent No. 2 e14188.