DE1958085C - Electronic switch with spring action - Google Patents

Description

change is blocked prematurely. The size of the potential change can be determined by the dimensioning of the Inductance of the switch core can be set.

The pause time of the astable multivibrator 10 following after the transistor 14 has been blocked is the same as in FIG an unloaded multivibrator mainly by the time constant of the resistor 20 and the Capacitor 16 formed ÄC-GIieds determined.

As soon as the voltage induced in the inductance 26 one of the threshold stage 11 and the in the Circuit used resistors falls below the dependent limit value, it can use the astable multivibrator 10 no longer tip back prematurely to the initial state, and the astable multivibrator vibrates at the specific frequency determined by its components. Above this limit However, the induced voltage increases the sweep frequency of the astable multivibrator to a higher level Frequency changes, with the frequency transition both in one and in the other direction occurs suddenly. With the frequency jump there is a sudden change in the output terminal 29 occurring DC voltage. The change in DC voltage is determined by means of the capacitor 33 sifted. The following special features result in the circuit:

The voltage induced in the switching core is less attenuated. The one parallel to the collector-emitter path of the transistor 15 of the astable multivibrator lying alternating current resistance of Switching decreases with decreasing inductance, which is caused by an adjustment of the permanent magnet 30 can be changed. With such an adjustment, the potential of the connection point 22 increases of the multivibrator has a smaller positive value, which shortens the charge reversal time of the capacitor 16 and thus the sweep frequency of the multivibrator is increased. By reducing the inductance of the switching core 26 can thus be increased the frequency of the astable multivibrator. the Electronic switch according to the invention thus also provides a device for erratic and variable Influencing the sweep frequency of an astable multivibrator.

1 sheet of drawings

Claims (13)

Claim subject is shown. In detail shows F i g. 1 is a block diagram of the electronic Switch, F i g. 2 the electrical circuit diagram of an inven- Electronic switch shown with an oscillator formed in accordance with 5-making switch, with an adjustable by an object ^he changeability D in ^the drawing, electronic loan inductance, characterized by switch consists of an astable multivibrator 10, an astable multivibrator (10) through one ^{of a} Schwellstufe 11, an inductor 12 and Schwellstufe formed suitably by a transistor stage ^mäßi 8 ^{to a} downstream amplifier 13. As in (11) through the Inductance (12) is loaded, the i »block diagram of FIG. 1 has a switching core (26), represented by arrows, which under the ^lst > there is a mutual influence between the variable influence of a permanent magnet in ^{the three} stages 10 to 12. (30) is, and the emitter-collector F ι g. 2 shows the three stages 10 to 12 of the electrical Route of a transistor (23) of the transistor stage. switch in the electrical circuit diagram. the and a resistor (25) is fed. * 5 Multivibrator 10 is made up of the two transistors 14 and 15, the coupling capacitors 16 and 17 and the resistors 18, 19, 20 and 21 according to known Formed design. Its through the junction of the collector of transistor 15 with the ao coupling capacitor 16 and the resistor 19 formed connection point 22 is with the base of a Transistor 23 connected, which together with a resistor 25 connected between its collector and positive pole 24 of a DC voltage source 25 forms threshold level 11 of the electronic switch. The inductive stage 12 is in the illustrated embodiment by a so-called switching The invention relates to an electronic switch core 26 which has a toroidal core 28, which is provided with an oscillator with a winding 27 with an adjustable inductance, whose inductance is variable. Your ₃₀ end with the emitter of transistor 23 of the threshold is based on the task, a sudden switching stage 11 is connected. The other end of the winding to enable a transistor stage 27 is connected to an output terminal 29, to A known proximity switch has an LC which is the one shown in FIG. 1 indicated amplifier 13 oscillator, which is connected near its switch-off. Not operated via controls the inductance of the switching point and a sine ₃₅ core 26 may write vibration shown in unspecified by. The linear LC oscillator has an adjustable permanent magnet 30 as a frequency-determining element to be influenced by an inductance. on, by influencing the damping of a between the output terminal 29 and the minus Resonant circuit is effected. This known approximation pole 31 of the DC power source is a stress proximity switch has - as well as other proximity ₄ "resistor 32 and parallel to a filter capacitor switch - the disadvantage that it no distinct down 33rd
Has jumping behavior. How the electronic switch works According to the invention, the task set is as follows: an electronic switch of the aforementioned After switching through the transistor 14 of the Type by that an astable Multivi- ₄₅ astable multivibrator 10, it is having the Kopplungskonbrator, the discharged via a transistor by a capacitor 16 through the transistor 14 and the step formed by the inductance Schwellstufe resistance 19th The transistor is loaded, and that the inductance has a switching core 14 via the resistor 20, which has between the base, which is under the variable influence of this transistor and the positive pole 24 of the _{direct permanent magnets, and that the inductance 5} "current source is placed, held conductive. In this circuit via the emitter-collector path of a transistor of the multivibrator 10 position is located at the base of the transistor stage, and a resistor fed transistor 23 of the Schwellstufe 11 a positive rake-By switching the multivibrator occurs at the voltage, so that this transistor becomes conductive and an inductance has a self-induction voltage, the current flow through the winding 27 of the switching core 26 from a certain size, the breakover frequency of the 55 takes place. The impact multivibrator when this current is switched on. It causes the multitend change in flux to generate a self-induction voltage at the switching core in bevibrator no longer with its own, but with a familiar way, which oscillates at a higher frequency. With this frequency change effective from the connection point 22 of the multivibrator, the ratio of the input will also become effective. The increase in the first positive half-switching time at the pulse gap time of the multivibrator 60 wave of this induction voltage changes the condensation. It is essential to the invention that the frequency generator 16 of the astable multivibrator 10 takes place suddenly when the multivibrator is changed and that the correct maximum value is charged. When a sudden change in DC voltage after the first half-wave subsides, the potential changes, which can be used for sudden switching of a transistor stage of the connection point 22 of the astable multivibrator. 65 from this maximum value in the negative direction. More details about the invention result from the This potential change acts via the condenser following description in connection with the gate 16 on the base of the transistor 14, the drawing, in which an embodiment of the invention after reaching a sufficiently large potential