DE1918184A1 - Contactless controllable switching device - Google Patents

Description

DR-INO. DIPL.-lNa. M. SC. DIPL.-PHVS. OR. DIPL.-PHYS.

HOGER-STELLCHT-GRIESSBACH-HAECKER

PATENT LAWYERS IN STUTTGART

A 37086 b ■ 1918184

March 23, 1969

Mr. Eduard Hermle

73o3 IJeuhausen (Filder) Kirchstrasse 2o

CONTACTLESS CONTROLLED SWITCHING DEVICE -

The invention relates to a contactless controllable switching device for switching on and off a load that can be arranged in a high-voltage load circuit, so / ie with a sensor that reacts to the approach of an object to be monitored and is fed with low voltage and controls a switch located in the load circuit.

A switching device of this type is already known in which an oscillator with a downstream discriminator is provided as the transmitter, which is damped when the object to be monitored approaches. A thyristor located in the load circuit is then ignited via the discriminator and serves as a switch for the high-voltage load circuit carrying 220 V, for example. The supply of the oscillator and. of the discriminator with low voltage is a transformer connected as a current converter, its primary winding

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lies in the load circuit. Let switching devices of this type Although they are designed in such a way that they have only two leads, namely high-voltage leads, but v / iron they have the disadvantage that they build relatively large, which can be attributed to the use of a transformer is.

The invention is now based on the object of providing a switching device of the type mentioned at the outset, which also only has two leads, namely two high-voltage leads, which on the other hand, however, are so small "can be trained, for example, in the usual multiple limit switch housings or in switchgear as a whole.

According to the invention, several possible solutions are possible to solve this problem:

According to a first approach, there is at least one semiconductor component to be provided with Zener characteristics for generating the low voltage. In a further refinement, the ses inventive concept can now be used to power the

Encoder parallel to the one designed, for example, as a Zener diode Semiconductor component a phase control for operating the switch and with the be connected to both poles of the latter. However, it is also possible to use the semiconductor component with Zener characteristics to put in the load circuit and to bypass the switch with a high resistance. In both Cases, the low voltage is referred to as a voltage drop at the Zener diode tapped; the Zener diode generates the - Voltage only when the switch is closed, becomes open ■ maintenance of the voltage supply for the encoder ... phase angle control is used. Otherwise .that ~ ' Semiconductor component with zener characteristics the required

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such low voltage then also "when the switch is closed generate in order to maintain the voltage supply for the encoder, if the switch is bridged by a high resistance.

With all of these possibilities of forming the Y / pus of the basic idea according to the invention, the construction can be constructed in a significantly more space-saving manner than is the case with the known switching device, since a transformer is no longer required
and, moreover, the switching device according to the invention can largely be created in an integrated design.

A second solution to the task at hand looks at
a switching device of the type mentioned for generating the low voltage in the load circuit before a voltage-dependent resistor, which is lower in resistance at high voltage than at low voltage.

In a third approach, it is proposed according to the invention to generate the low voltage in the load circuit
to arrange an electro-opto-electrical converter.

The two last-mentioned possible solutions also have the advantage that, as a result of the omission of a transformer, the entire device is made relatively small
and can be manufactured at least partially in an integrated construction. '. ··· .. ·· -. ,. ■

Embodiments of the switching device according to the invention which are built into conventional multiple limit switch housings or switching mechanisms are particularly useful; but it is also possible to accommodate the switching device in a tube, which in particular by means of a thread in a
Mounting bracket is held. The embodiment mentioned last allows easy adjustment of the

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switching device according to the invention.

Finally, it is also advisable to embed the switching device in a casting compound in order to make it less sensitive to mechanical stress.

Further details and features of the invention can be taken from the appended claims and / or the following description, which serves to explain the exemplary embodiments of the invention shown in the drawing.

1a is an overview circuit diagram of a first embodiment - example of the invention,

FIG. 1b shows a time diagram for current and voltage of the exemplary embodiment according to FIG. _1a

1c shows an overview circuit diagram of a second exemplary embodiment of the invention,

2a shows an overview circuit diagram of a third exemplary embodiment the invention with two zener diodes in the switching circuit,

2b shows an overview circuit diagram of a fourth embodiment. . rsungsbeispieis of the invention with a Zener diode in the switching circuit, ^l .

3 shows an overview circuit diagram of a fifth exemplary embodiment of the invention with a VDR-V / resistor in the switch circuit _?

Pig. "4 a" layout diagram of a sixth embodiment of the Leiepielo of the invention with an electrical

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opto-electrical converter in the switch circuit,

Fig. 5 is shown in detail by a circuit diagram Execution of the general circuit diagram of Fig., 1c,

Pig.6a is a view of ^{xs oC mounting switches according to the} invention mounted on angles in a pipe with an external thread,

Pig. 7 is a view of an IT proximity switch according to the invention in a limit switch housing,

Pig. 8 shows an arrangement according to the invention Proximity switches that are housed in a single housing of a multiple limit switch, and

Pig. 9a. ■

and FIG. 9 ″ b views of proximity switches according to the invention in FIG a rear derailleur seen from the side or from the front.

In the pig. 1a to 1c is the inventive in general circuit diagrams or in a time diagram Solution of proximity switches by means of phase control shown. ; · ■■■

A contactor coil 10 is used in Pig. 1a by an alternating voltage U operated via a gate switch 12 if the latter closes. The two poles of switch 12 are via lines 14 and 16 to an ignition device 18 and led to a chasing part 20. An ignition line 22 at the output the ignition device. 18 leads from this to the control input des Torsehalter.3 12. The power pack 20 is used for aligning.

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direction of the incoming alternating voltage as well as keeping constant an output plus-minus voltage · The latter is a low voltage that is used to feed the ignition device 13 and a proximity-sensitive transmitter 23, 24, which preferably consists of a discriminator 23 and an oscillator 24; the output of the oscillator 24 leads to the input of the .Diskriminators 23 »whose output is applied to the ignition device 18. * Indicate a use of other types of encoders, the magnetic example by means of Hall probes Peldplatten or an approximation Feldei, would also be possible.

w The oscillator 24 oscillates at a frequency of, for example. 10 UHz. Other frequencies, such as 0.1 IiHz. would also be conceivable as the operating frequency of the oscillator. The oscillator 24 is approach-sensitive with regard to the approach of a cam of a machine tool or the like, as its phase, frequency and / or amplitude can be represented as a puncture of the distance between the oscillator 24 and the nook. Correspondingly, the discriminator 23 is designed to discriminate the phase, frequency and / or the amplitude of the oscillator 24. Discriminator 23 and oscillator 24 have a total threshold characteristic in that a subliminal value indicates that no or at least insufficient approach of a crouch took place on the oscillator; in the opposite case, an over-threshold value is displayed by bringing the cam closer to one another. on the other hand solves the output signal from the discriminator 23 the. ......

Ignition device 18, which now closes the gate switch 12 by in-phase ignition pulses on line 22. ,

The mode of operation of the exemplary embodiment according to FIG. 1a will be explained with the aid of the timing diagram in FIG. 1b. In the latter, a curve a represents the current through the gate switch _s a / curve b represents the voltage drop-1 at the gate switch 12. A first time c indicates that the discrete · ·. - · ■. '

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minator and oscillator existing food sensitive Encoders 23, 24 report a sufficiently approximate part, but a second time d shows the opposite case by the nuance-sensitive encoder no or no sufficient sewn-on part reports. ;

A load-related phase shift between current and Stress should not be taken into account. The alternating voltage U is 220 volts, 50 Hz. Thus, a half-wave of the current or the voltage lasts 10 msec. Since currently d the proximity sensor does not act on the ignition device 18, the gate switch 12 remains open continuously, which is why through there is no current flowing at this time (curve a at time d), while the potential difference between lines 14, 16 is 220 volts at 50 Hz (curve b at time d).

At time c, however, the ignition device 18 ignites the gate switch 12 via its output line 22 by about 10 meec. after the zero crossing of a half-wave the gate switch 12 closes, which due to its inherent ignition and combustion characteristic now remains closed until the half-wave has subsided and has its next zero crossing. The gate switch 12 is expediently represented by a bi-directional thyristor, which is triggered in both directions 10 msec after each zero crossing.

Curves a and b have corresponding jump functions at time c. However, while corresponding notches in the course of the curve a ar / sich are undesirable, however, the over 10 msec. increasing voltage drop at the gate switch 12 for further feeding the power supply unit so / ie for maintaining the ignition in the ignition device 18 '. The power supply 20 must therefore have the property of maintaining the PIus-Hinus voltage at its output in spite of the now visibly reduced and higher F-noise

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to maintain the provided input voltage so far, that with her a flawless working of the meander 23, 24 and the ignition device 18 is ensured.

A second embodiment also with phase - Section control and full wave section is shown in Fig. 1c. Input terminals 30, 32 lead through a full wave rectifier 34 to a simple thyristor 36, whose _An-odeiileitung 38 and cathode line 40 to the input of a .Beschneiders 42 is placed. Line 40 also serves P as an input line for an ignition device 44. An ignition line 46 leads from this to the gate input of the thyristor 36. Lines 48, 50 lead from the output of the trimmer 42 to the ignition device 44 and via a Separating and buffering device 54, 56 to the proximity sensor 23, 24. The separating and buffering device consists of one Isolation diode 54 and a buffer capacitor 56; it creates a sufficiently smoothed DC voltage by having its output line 58 plus voltage compared to the minus voltage having leading line 50.

The mode of action of the Pig. 1c is the circuit shown

»To say that through the intermediate wave rectifier 34 and the thyristor 36, which only allows current to pass in one direction the same effect. is achieved as in Pig. 1a through the bidirectional transistor 12, happened. One advantage of this Circuit in Fig. 1c over that in Fig. 1a is that one from the trimmer 42 and the separating and buffering device 54, 56, which is connected downstream of the thyristor 36 The power supply unit no longer has to carry out voltage rectification, as happened in the power supply unit 20 of FIG. 1a. There are further advantages over the first exemplary embodiment in a simplified ignition device and 'a small internal buffer capacitor. The "basic mode of action

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according to Pig's arrangement. 1c, however, is completely the same as that described above. The circumciser is expediently limited 42 the single, fully rectified voltages about the level of the voltage reached after about 1 msec. A detailed description of the second embodiment takes place below using the circuit diagram of the Pig. 5.

A third embodiment of the invention is provided by Pig. 2a shown. Two oppositely polarized zener diodes 60, 62 are in series in the switching circuit of a gate switch 64. A high-value shunt resistor 66 bridges the switch 64. Lines 68, 70 apply the voltage drop occurring at the Zener diodes 60, 62 to one Ignition device 71 and via a separating and buffering device 73, 74 to the proximity sensor 23, 24.

As long as the switch 64 is open, there is a small current flow through the Zener diodes 60, 62 and the shunt resistor 66. As a result, a 50 Hz square wave potential builds up between lines 68 and 70. This will on the one hand smoothed by the device 73, 74 and thus supplies the proximity sensor 23, 24 with operating voltage; .On the other hand, it directly feeds the ignition device 71, the in the case of adequate approach of an object Gate switch 64, preferably designed as a bidirectional thyristor, ignites. The ignition 'can immediately after' the zero crossing take place, a delayed ignition in Phase control is not required. Due to the Zener diodes located in the switch circuit, the switch 64 is also in the hold state during the state of the switch 64 the same voltage between lines 68 ,; 70 like. appear beforehand. Because the compulsion to a phase angle control omitted, switch 64 does not need a switch with ignition

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characteristic to be, where.by then also, the ignition device 71 would be omitted. One of the two Zener diodes 60, 62 are also omitted.

Pig. In a fourth exemplary embodiment, FIG. 2b shows the latter Modification options of the third version

. example (Pig. 2a), with the switch 64 with ignition characteristics of Fig. 2a by a tran-

• sistor 84 with upstream full-wave rectifier 86 was replaced. Otherwise, this embodiment is similar to the one discussed above, which can be easily recognized. because the same reference numerals have been chosen for the same components.

Since a voltage dependent resistor (VDR resistor) the Characteristic of two series-connected and oppositely polarized Zener diodes, means the fifth Embodiment in Pig. 3 merely a further modification of the third exemplary embodiment of the Pig. 2a. Comparable components are given here with a prime, but otherwise identical reference numerals as in Pig. 2a expelled. A VDR resistor 80 in Pig. 3 takes the place of the Zener diodes 60, 62 in Pig. 2a. In the same way could in the embodiment of the Pig. 2b, the Zener diode 60 is replaced by a VDR resistor.

In'Pig. 4 shows a sixth exemplary embodiment of the invention, which has the primary side of an electro-opto-electrical converter 90 (series connection of an electro-optic and an opto-electrical converter) in the switch circuit, while the secondary side of the Wändlers 90 a ITiederspannungs- or current source "forms, the ■ from a liäherungsgeber and a possible ignition device an aggregate 92" · fed in. In a simplest embodiment, a forward ^first ·

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Semiconductor switch 94, preferably provided with ignition characteristics, has a full-wave rectifying effect, so that the proximity switch operated contactor coil is operated with only positive or only negative half-waves. A secondary resistance 96 short-circuits the switch 94 and is high-resistance enough to keep the on / off switching ratio of the proximity switch large enough and, on the other hand, a luminous flux to be maintained in the converter 90 even when the switch 94 is open to ensure that the unit 92 is adequately supplied.

If, on the other hand, the switch 94 has bi-directional characteristics, the light-emitting components on the primary side of the converter 90 would also have to be bi-directional, which in the case of light-emitting diodes on the primary side ¹ requires an anti-parallel connection of such diodes.

All the exemplary embodiments according to FIGS. 2-4 have a switch connected in parallel to the switch circuit Shunt resistance. This is necessary as long as the voltage drop detected in the switch circuit As the resistor lying in the main circuit, it is the only energy source for supplying the control circuits of the proximity switch also during the open switching state. However, if you see a second source of energy directly ah the connections of the proximity switch, i.e. in the ■ shunt circuit of the proximity switch, Not only the shunt resistor can be omitted, but also the on / off switching ratio of the proximity switch generally be improved. In the case of the exemplary embodiment according to FIG. 4, this would mean expanding the electro-opto-electrical converter 90 to the extent that possibly light-emitting diodes connected in anti-parallel additionally in the shunt circuit of the proximity switch

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ters · can be inserted. The other exemplary embodiments received additional Zener diodes or VDR resistors in the shunt circuit, their voltage drop via isolating diodes (exclusive OR link) to one for the voltage drops on the main and shunt circuit common buffer device would be performed.

In the mode of operation, the exemplary embodiments according to FIGS. 1a and 1c differ from the exemplary embodiments according to FIGS. 2 to 4, in particular in that the former have a phase control operating with a defined time delay, while the latter have none. Accordingly, the extraction of energy for the low-voltage supply of the control circuits of the mowing switch was pulsed in the former case, but not in the latter. If one now equips the embodiments according to FIGS. 2 to 4 with a phase control, which, however, in contrast to the first two embodiments, would have to work in such a way that at the time when the switch in the switching circuit is normally fully blocked If a certain lower current pulse per half-wave (preferably at the end of the half-wave) that is still permissible to maintain the required switching ratio would flow, then on the one hand the J-shunt resistor as well as the last proposed second energy source in the I-shunt circuit could be omitted. This means that a sufficient chip ^': voltage drop ensures at the in-switch circuit resistance with preferably non-linear in the single as off state of the switch.

In addition, it should be mentioned that the embodiment of FIG directly, as well as the embodiment of FIG. 2b with or without the rectifier 86 also for switching Equal banners can be used. · '·

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Fig. 5 shows a flow chart detailing the in Pig. 1c shown as an overview diagram of the second embodiment, a comparison being made easier by using the same reference symbols. Between connections 100, 101 is a mains voltage of 220 volts, 50 Hz. Between these and the connections 30, 32 of the proximity switch The protection coil 10 and interference suppression impedances 102a are themselves switched to 102 c. The full-wave rectifier 34 with diodes 34a to 34c converts the signals at the connections 30, 32 AC voltage located between the anode line 38 and the line 40, 50 measurable pulsating DC voltage, provided that the between these Tyristor 36 blocks.

The trimmer 42 of Fig. 1c is shown in Fig. 5 by the Components 104 to 114 shown. These are a voltage divider 104, 106 from a resistor 104 and a zener diode 106, at the output of which the zener stabilized voltage Via a diode -108 to an emitter follower transistor 110 is brought, which works as an impedance converter and via an emitter resistor 112 directly the ignition device 44 (Fig. 1c) feeds. The transistor 110 has between collector and emitter a capacitor 114.lie a slight smoothing of the rectified half-waves at the time the zero crossing and thus the effective operation of the transistor is guaranteed even at this time.

The emitter follower output marked as line 48 of the trimmer 42 (FIG. 1c) feeds the ignition device 44 which, in FIG. 5, contains the components 116 to 130. A semiconductor component 116 with ignition characteristics, for example a unijunction transistor, has in its input circuit an impedance network 118, 120, 122 'consisting of resistors 118, 120 and a capacitor 122. They have a common connection point at the control input 'of the building

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partly 116, the resistor 118 to the line 48, the Capacitor 122 on line 40, 50 and the resistor is connected to the output of the discriminator 23 (Fig. 1c). The anode of the component 116 is via a V / resistor 124 to line 48, the cathode via the parallel connection from a resistor 126 and a voltage divider ler 128, 130 connected to the line 40, 50. The tap . of the voltage divider 128, 130 is connected to the gate terminal of the thyristor 36 out.

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\ The separation and buffer means 54, 56 of the diode 54 and the buffer capacitor 56 is located between the conduit 48 and the conduit 58, the latter is a positive soft and sufficiently smoothed DC voltage over the line 40, 50 has. The discriminator 23 (FIG. 1c) in FIG. 5 consists of three inverters connected in series with inverter transistors 132, 134, 136, of which the first two have load resistances 138, 140. The output of the first inverter also has an integrating RC network of a capacitor 142 and a resistor 144, in which the capacitor 142 between the collector and emitter of the first inverter transistor 132 and the resistor 144 between the output of the first and the input of the second "Inverters lies.

The oscillator .24 (Fig. Tc) is in.Fig. 5 between the potential of lines 58 and 40, 50 in the form of three intermeshed voltage dividers with R, L, C components and an active component. A first voltage divider 150 to 154 with a resistor 150, a diode 152 and another resistor 154 feeds with a common Junction point between resistor 150 and the Diode 152 the control input 'of an active component, which to belongs to a second voltage divider. The second voltage divider contains an inductor 156, an HPN transistor '

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158 as the active component and one downstream from it at the emitter Trimming resistor 160. The third voltage divider forming the oscillator 24 consists of the series circuit three capacitors 162, 164 »166 and a resistor 168, which is placed on the line 40, 50. During the common The circuit point between the capacitors 162 and 164 is connected to the tap of the trim resistor 160, the common circuit point leads between the capacitors 164 and 166 to the collector of transistor 158 and the one connection of the inductance 156, the second on the line 58 is located. The common switching point between the capacitor 166 and the resistor 168 form the output of the oscillator and leads to the input of the first Inverter of the discriminator 23 and thus to the base of the inverter transistor 132. The series connection of the resistor 154 and diode 152 is such that the resistance 154 is connected to the line 40, 50, but the cathode of the diode 152 is connected to the base of the transistor 158.

• The oscillator 24 is designed so that it works with about 120 IcHz oscillates freely as long as the inductance 156 does not detect the proximity of a metallic object. He follows but such an approximation, the damping of the oscillator finally reaches such a degree that the oscillation rips off. In practice this means that one on sufficient Approach to be tested crouching of a machine part or the like made of plastic, which only has a metal layer on its surface.

The discriminator 23 (Fig. 1c) is a pure one in Fig. 5 Amplitude discriminator in which the transistors 132, 136 block fully as long as the oscillator 24 is sufficient due to Drilling is inactive, but vice versa in which the transistor 136 is fully conductive as long as the oscillator is freely oscillating.

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As long as transistor 136 conducts, it pulls over you. Voltage divider from the resistors; 118 * 120 the Stetter potential for component 115 deep plastered around an ignition to prevent the latter effectively and permanently. As soon . however, a damping of the oscillator 24 occurs, begins also the transistor 136 to .lock, which means, that .. the capacitor 122 via the resistor 118 as a charging resistor ^ stand can charge. Finally is the ignition voltage (Hump tension) of component "1-16 is reached, this ignites, whereby its cathode potential is raised so far that as a result, via the tap on the voltage divider 128, 130, the thyristor 36 is also ignited directly.

If the thyristor 36 now only remains conductive until the voltage has passed through zero and then goes out, a subsequent ignition process must be initiated with the rise of each half-wave in the "/ or" until reliable ignition / the Tyristor.s 36 a potential build-up z ^ tfischen the anode —- line.38.and the line 40, 5Q- takes place, which, moreover, suffice ΐημβ to over the separating and buffering ■ .- ■. -Direction 54, 56 to ensure a sufficiently positive potential on line 58; Can it be useful ^? . During the period of inactivity of the oscillator - 24. on the ι line, .58 a kind of emergency voltage supply take place, / which only ensure that the inverter transistor .. · .. ■ .13.6-remains blocked at the discriminator output and the oscillator 24 can again oscillate after removal of the damping. . . , ... - .... - ■ ..- ". ■

The mode of operation of the second ignition and all subsequent ones -Ignitions is- that, -that the potential curve on the anode- ' line 38 and line 48 after the '• Tull passage of the' Operating voltage is the same, and that the RC time constant ' the series connection of the resistor 118 and the condenser

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sators / has been dimensioned in such a way that there is sufficient ignition voltage after et v / a 1 msec, at the control input of component 116 has built up, which can ignite this so at a point in time at which between the line 48 and the line 40, 50 a has formed sufficient potential that is sufficient to have a sufficiently positive voltage across the 'voltage divider output of the Voltage divider 128, 130 to apply to the gate input of the thyristor 36 for its ignition. As soon as the thyristor 36 is ignited has, breaks the potential between the anode line 38 and the line 40, 50 and in the same way the potential of the Line 48 together except for the thyristor operating voltage. The embodiment of Pig.5 v / eist circles, which are preferably only generate power dissipation at the times when their activity is required.

Pig. 6a shows a perspective view of a proximity switch mounted on an angle 200 in a tube 202 External thread; The circuit of the switch according to the invention is expediently embedded in a cast resin in this tube. Two mutually locked nuts 204 »206 hold the tube 202 on the angle 200, but at the same time allow the end face of the tube as an active face 208 not only in the height, but due to a preference \\ travel slit-shaped formed hole to adjust laterally when the pipe passes through the angle. Serve the assembly of the bracket itself Holes 210, the dimensions of which · A 'and B correspond to the DIII proposal' for roller lever switches correspond and the zui? ^ easier adjustment slot-shaped can be formed.

The Pig. 6b and 6c. show a further angle construction for receiving a proximity switch, in which the angle consists of angle parts 200 'and 200 ″, which are articulated to one another by an IJiet 209. The angle part 200 ″ carries the tube 202 which receives the proximity switch in the same way. _; . ^: eite like d * r ', / inlol 200 in? ig.6a, but it is in the lower

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separated from these with lying on an arc around liiet 209 Slits 210 · provided. By loosening screws, the part 200 ″ and thus the active surface 208 on the front The end of the tube 202 is pivoted radially v / ground. '■

Fig. 7 shows the view of a proximity switch 212 according to the invention in an end switch housing 214-, in which the Proximity switches expediently in an epoxy resin 215 is poured. . .

Fig. 8 shows the view of the proximity switch according to the invention 216a to 216e in a housing 218 in which they are used as multiple limit switches are arranged. Such an arrangement proves to be particularly favorable for machine tool controls.

Finally, FIGS. 9a and 9 *> show a side and a front view of inventive proximity switches 220 in one Schaltv / Erk 222. Such arrangements make it possible to carry out non-contact position measurements of moving parts in crowded areas Carry out construction method without the various specialist parts of the previous methods (contact electrical, passive or active inductive, capacitive or photoelectric) are increasing have to.

Changes to the embodiments shown are possible within the scope of the inventive concept. In particular, it should be noted that it is not just that from a proximity-sensitive Oscillator with a downstream discriminator existing transmitter can be used in the proximity switch according to the invention, but also any other type of transmitter, the one Indicates approach. For example, an encoder equipped with field plates or Hall probes would be used for the approximation magnetic fields reports, can be used in the same way.

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Claims (1)

A 37 086 b 23.3. ^ 9619 ■ "" β * π P a t en t a-n s p, r ti. before on and off of a load in ejpxeftf * High voltage-s-Lasfkreis arranged v; kan ground »- ^ sov / ie nit einefti on 'approach of a to überyärdTenden object responsive' donor *", the niijü-iixederspannxing: is fed and in Iastkr> i ^ iiegend S _o holder controls, gekennzeichnej ^^ Iurch at least one semiconductor component with 2 »Device according to claim 1, characterized in that the semiconductor component is a Zener diode. 3. Device according to claim 1 or 2, in which the high-voltage load circuit with- AC voltage: fed- v / earth, -., characterized by, that -for power supply · .the encoder parallel to the Kalbleleiter component, a phase control for the. Actuation of the switch , and rn.i-t connected to the two poles of the latter ... - 4. Device according to claim 1 or 2, characterized in that: that ^! the semi-conductor construction element with “energy characteristics: in load circuit” lies and the switch: through a. . high resistance is bridged. - 5. Device according to claim 4, characterized in that • two oppositely directed Zener diodes lie in load circles. .. "" ...-- 6. Establishment according to one or more of the above Claims, characterized in that there is a rectifier in the load circuit. -20- 009842/1529 BATH ORIGINAL A 37 086 b k-b 1Ό1818Α - '23 .3.1969 ν JtO 7. Device according to one or more of the above Claims, characterized in that for buffer purposes a capacitor with an isolating diode between the semiconductor component with Zener characteristics and the transmitter lies. " "8. Device according to one or more of claims 2-7, characterized by an impedance converter for the Zener diode. 9.Contactless controllable switching device for switching "and switching off a load that is in a high-voltage Load circuit can be arranged, as well as with a reacting to the approach of an object to be monitored Encoder that is fed with spring tension and one controls lying in the load circuit switch, characterized in that to generate the low voltage in the Load circuit a voltage-dependent resistor is arranged, which has a lower resistance at high voltage than at lower voltage is 10. Contactless controllable switching device for switching a load on and off in a high-voltage load circuit can be arranged, as well as with an on Approach of an object to be monitored reacting transmitter, which is fed with low voltage and controls a switch located in the load circuit, characterized in that an electro-opto-electrical converter is arranged in the load circuit to generate the low voltage. . ■ _ 11. Device according to one or more of the preceding claims, characterized in that the switch an ignition characteristic. -21- ^009842/1629 BADOR ₁ G ₁ NAL A 37 086 b 12. Switch according to claim 6, characterized in that the switch is a thyristor or a bidirectional thyristor is. 13. Device according to one or more of the preceding Claims, characterized in that the transmitter has a proximity-sensitive oscillator and one Has operating state of the latter monitoring discriminator. 14. Installation according to one or more of the preceding Claims, characterized in that it is built into a multiple limit switch housing. 15. Device according to one or more of the claims T -.13, characterized in that it is built into a tube, which in particular by means of a thread is held in a mounting bracket. 16. Device according to one or more of the claims 1 - 13 »characterized in that it is in a rear derailleur is built in. 17. Device according to one or more of the preceding claims, characterized in that it is in a Potting compound is embedded. BATH ORIGINAL A 37 086 b b - 135 I * ». Jan. 1970 Claim Contactless controllable switching device designed as a two-pole switch for connection to a switch to be interrupted High-voltage load circuit, with a sensor reacting to the approach of an object to be monitored, which is connected to the Low voltage is to be connected and one in the high voltage load circuit The switch to be placed in series controls the is connected in parallel with the encoder, so that this parallel connection forms the two-pole, indicated by at least one semiconductor component with Zener characteristics to generate the low voltage for the encoder. 0098A2 / 152Q - ■ BAD ORIGINAL