DE1613036A1 - Switching arrangement for the cyclical supply of an electrical consumer from a direct current source - Google Patents

Description

161303S

R. 8996
October 17, 1967 Rb / Sz

Attachment to

Batentanme 1 application

R 0 BE RTB 0 S GS GMBH, Stuttgart W, Breitscheidstrasse 4

Switching arrangement for clockwise ^ supply of an electrical consumer from a direct current source

The invention relates to a switching arrangement with a consumer, which is fed with pulsed direct current from a direct current source via a first thyristor, with the purpose of extinction a second thyristor is provided for the first thyristor, and with at least one pulse generator to control the two thyristors.

A known circuit arrangement of this ILRT includes an astable MultivibraboF, wherein a pulse is given to the harvesting Thyriabor in each case at the beginning of a Multivibratorimpulsea, making it conductive, and at the end of MuItivlbratorimpuls it becomes. 'T'hyristor geKoben a pulse to don "ssweLben, ^is vroduroh this locked · / -

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Robert Bosch. GmbH ■ R. 8996 Rb / Sz

Stuttgart

By. It is in this known switching arrangement to increase the pulse frequency it is possible to increase the current through the first thyristor, but only in a certain range that is necessary for some applications is too small.

It is an object of the invention to enable a larger adjustment range here with simple means. According to the invention, this is achieved in a switching device mentioned at the outset in that a first pulse generator is provided to control the first thyristor and a second pulse generator is provided to control the second thyristor, that the first pulse generator blocks the second pulse generator when the first thyristor is locked and that a common actuator is provided for both pulse generators. Here, it is advantageously followed in which both encoder included in a known manner depending a capacitor, the charging current can be adjusted and which controls the delivery of a _r ignition pulse by the encoder at a given charging voltage, and that the charging currents of the two capacitors in the Way can be set in opposite directions so that an increase in one charging current corresponds to a decrease in the other charging current, or vice versa. Such a switching device has a very simple structure with a wide range of adjustment.

Further details and advantageous developments of the invention result from the exemplary embodiments described below and shown in the drawing.

Show it:

FLg. 1 an embodiment of a switching device according to the invention,

Kig. 2 diagrams to explain the mode of operation to 4 of Fig. 1, and. -

O 0 9 8 8 57 0 h 5 ÖBAO original

Robert Bosch GmbH R. 8996Rb / Sz

Stuttgart *

5 shows a variant of the layout of Mg. 1.

The Sch shown in Fig. 1. al tan order is used to control an eddy current brake of a motor vehicle. This eddy current brake has a magnetic swing 10. A strong current flows through it the magnet winding 10, so is strongly braked. On the other hand, only flows. ■ a weak current through this winding, then the motor vehicle, stuff only weakly braked. (The motor vehicle and the actual Brakes are not shown as they are well known.)

The current i through the magnet winding 10 is controlled by a control element 11 controlled, which serves as an actuator. Serves as a direct current source a battery 12 of ζ. B. 24 V voltage. .

A first thyristor (SCR) 15 is provided to control the current i; This is a controllable rectifier with thyratron-like characteristics, which only comes back after switching on blocks when its anode becomes more negative than its cathode »Zum Blocking the thyristor 13 are a second thyristor 14 and a Capacitor 15 is provided. ·

Used to deliver the ignition pulses for the first thyristor IJ a first pulse generator 16, and for delivering the ignition pulses for the second thyristor 14 is a second pulse generator 17, which both each contain a two-base transistor 18 or 19, (English: unijunction transistor), each with an emitter connection Em and two base connections Bl and B2 have. In such a two-base transistor, if the voltage exceeds between Bl and Em have a certain value, the distance Bl Em conductive, as is familiar to the person skilled in the art.

00988S / 04 5 8

hobert Bosch GmbH If R. 8996 Rb / Sz

Stuttgart

A potentiometer? 2 is used to control the two pulse generators 16 and 17. (z. B. 10 kOhm) with two connections F and D and a tap 23 with a connection E. The tap 23 is coupled to the brake pedal 11 that or rsich shifts in the direction of the Annchluli 1) to the connection F when braking harder , the current i through the first thyristor 13 steadily increasing, as is shown graphically in FIGS.

In detail, the switching arrangement is constructed as follows: The positive terminal of the battery 12 is connected to one of a relay 24 actuated contact 25 with one terminal of the magnet winding 10 and the cathode of a diode 26 connected, which in the present case serves as a free-wheeling diode and its anode at a connection point 30 to the other terminal of the magnet winding 10 and via the primary winding 27 of a transformer 28 with the anode of the thyristor 13 connected int, its cathode, as well as the cathode of the thyristor 14, with one connected to the negative pole of the battery 12 IiinusJ ni device 29 is connected;

The capacitor is located between the anodons of the thyristors 13 and 14 15 (e.g. 100 / uF); the anode of the thyristor 14 is connected to the cathode connected to a diode 32, the anode of which via the secondary winding 33 of the transformer 28 is connected to the negative line 29.

The relay 24 is connected to the positive terminal of the battery 12 and with the other connection via one operated by the brake pedal 11 Contact 34 · connected to the negative line 29, with which also via a Resistor 35 (z. B. 200 ohms) and one of the brake pedal 11 actuated tone Contact 36 the anode of the thyristor 14 is connected.

The contacts 34 and 36 are designed so that when braking (stepping down of the brake pedal 11) first the contact 34 is closed and thereby also the contact 25 is closed via the relay 24, and that the contact 36 is only opened with further braking.

■. 5 .- - '0098 85/04 5 8 _BAD

Robert Bosch GMBH . . -. R. 8996

Stuttgart ■

The pulse generators 16 and 17 are constructed in the same way. The first base B1 of the transistor 18 is connected directly to the control electrode of the thyristor 1 $ and via a resistor 37 (e.g. 20 ohms) to the manual circuit 29. Its second base B2 is connected via a resistor 38 (e.g. 100 ohms ) connected to the cathode of a Zener diode 39, which in turn is connected to the cathode of the freewheeling diode 26 via a resistor 40, while the anode of the Zener diode 39 is connected to the negative line 29. As can be seen, when the contact 25 is closed, there is a constant voltage across the Zener diode 39, e.g. B., as shown in Fig. I, 8 V »| This constant voltage serves as the operating voltage for the pulse generator. 16 and 17 ·.

The emitter. Em of the transistor 18 is connected via a capacitor 43 (z. B. 1.5 'JiF ") to the minus line 29 and via a resistor 44 (e.g. 200 ohms) to the terminal F of the potentiometer 22, the terminal of which E is connected to the cathode of the Zener diode 39 and its connection D via a resistor 45 (e.g. 2.7 kOhm) to the emitter Em of the transistor 19 * As can be seen, the resistance is over ten times greater than the resistor 44 | this Dimensioning has proven to be favorable. ■■ ', -'- "■

The first base B1 of the transistor Ϊ9 is directly connected to the control element! trode of the thyristor 14 and via a resistor 46 (e.g. 20 ohms) connected to the mini line 29. His second base B2 is over a resistor 47 (e.g. 100 ohms) connected to terminal E, and between its emitter Em and the negative line 29 is a - ' Capacitor 48 (e.g. 1.5

A diode 51 is with its cathode at the point 30 and with its Anode connected to the emitter of transistor 18. An npn transistor 52 is m.tb its collector to the emitter of the transistora and with an emitter it is calibrated to minus exercise 29 Baals iat with the anode · 2ener diode. 54 ■ tiad »- üboi? a cons-55 from z * ß. 25 kOhm - with; the minus life "W VöfburiUßiu Die

, BAD OFMGihiÄL

Robert Bosch GMBH . R. 8996 Rb / Sz

• Stuttgart

The cathode of the Zener diode 54 is connected to a resistor 56 (ζ. B. 25 kOhm) connected to point 30.

The switching arrangement according to FIG. 1 operates as follows: It is initially assumed that the potentiometer 22 is in the in Fig. 2 is the position shown. When the brake pedal 11 is depressed, the contact 34 and via it and the relay 24 is first. Contact 25 closed. This allows the primary winding via the winding 10 27, the capacitor 15, the resistor 35 and the contact 36 a current flow which charges the capacitor 15 so that its left electrode is more positive than its right electrode.

At the same time, the Zener diode flows from point 30 via resistor 56 5 ^ and the resistor 55 a current to the negative line 29, the Keeps transistor 52 conductive so that it bridges capacitor 48 and - prevents it from charging. The second impulse generator / is blocked by this,

Likewise, a charging current flows from the battery 12 via the resistor 40, the tap 23 of the potentiometer 22 and the resistor 44. to the capacitor 43, which charges it according to an exponential function.

When the voltage across the capacitor 43 has reached a certain value, ·. the path Em-B1 of the two-base transistor 18 suddenly becomes highly conductive, the capacitor 43 being discharged via the resistor 37 and generating a positive voltage pulse at the time ti (FIG. 2) which ignites the thyristor 13. As a result, the potential at the right electrode of the capacitor 15 falls almost by the full battery voltage, e.g. B. by 24 V, so that the linko electrode becomes correspondingly negative and a swinging process begins via the diode 32 and the secondary signal 33; this leads to the reversal of the charge, capacitor 15, a> that now a fenced electrode potiitlver Ltst alo aoirio Left Klektrodo «

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iiobcrt Bosch GmbH. ^:: - ¹ I- 8996

Gtul / bgart "- .." ..

Λη dv.T magnet winding 10 is, -now practically., The full battery- 'npanauHi ¹ ; (In Figs. 2 to 4, the voltage on the winding 10 is shown with solid lines) and the Strom.i in it increases exponentially. (The current i is shown in dashed lines in FIGS. 2 to 4.).

"The point 50 now has almost the potential of the negative line 29, and the capacitor 43 can initially not recharge because it is practically short-circuited via the diode 51, that is the first Pulse generator is now blocked.

Simultaneously, transistor 52 "is nlchtioj tend, as DIC Kostspaunung between the point 30 and the negative line 29 is not enough more 'AIM ■, to make the Zener diode 5 ^ conducting and hence the transistor 52 no longer receives base current. The capacitor 48 can now be charged via the resistor 40, the potentiometer 22 and the resistor 45, and after a time tg (FIG. 2) the path B1 - Em of the two-base transistor 19 becomes conductive and a pulse is generated which the thyristor 14 makes conductive.

The capacitor 15 takes over the current previously carried by the thyristor 13 and thus leads to the extinction of this thyristor 13-

. _. .... - In doing so, the capacitor becomes 15 is charged again to about 24 V as described at the beginning, and point 30 becomes positive again, so that "described above" the pulse generator 17 blocked again and the pulse generator 16 released will. The thyristor 14 is non-conductive when the capacitor 15 is loaded. ·

The capacitor 43 now charges again via the resistance of the potentiometer 22 and, after a time t _{A, reaches} the breakdown voltage of the transistor 18. This tent t. is in the potentiometer position according to Fig. 2 therefore longer than t _E , because the potentiometer resistance of about 10 kOhm plus the resistor 44 (0.2 kOhm) in the charging circuit dos capacitor 43, while in the charging circuit of the Kondonfratorn 48 in this position only about 2.5 lying cool.

009885 / 0Ü58 baoüTOa. ,, '

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Robert Bosch GMBH' . R. 8996 Rb / Sz "

Stuttgart

As long as "the thyristor 13 is blocked, it flows through the freewheeling diode 26 an exponentially decaying current i, which is generated by the magnetic energy stored in the winding 10. This current maintains the braking effect in the pulse pause.

As can be seen from Fig. 2, the potentiometer is in this position The pulse spacing is large in relation to the pulse duration, and it just flows a small stream i.

If the potentiometer 22 is set to its middle position shown in FIG. 3, the resistance in the charging circuit of the capacitor 4-5 becomes smaller and the time t. decreases accordingly, while the time t " increases. As a result, the current i increases, as shown in FIG. 3.

If the potentiometer is adjusted even more to that shown in FIG. 4 Situation, then the time t ^ continues to increase, since the charging resistance of the capacitor 48 increases sharply. The time t. however, continues to decrease. A correspondingly high current i is obtained in the winding 10, since it is connected to the battery 12 almost all the time.

♦)

With a switching arrangement according to the invention one can thus / the equal

Adjust the current through a consumer continuously and practically without loss, in a very wide range. The invention is of course not only suitable for brakes, but z. B. also for DC magnets, DC motors, excitation circuits and the like. It can also be used in automatic control loops; z. For example, instead of the one potentiometer 22, the emitter-collector path for transistors can be used as charging resistors and these can be controlled by appropriate voltages. - The 'circuit is characterized by a simple structure, "which is achieved above all by the mutual locking of the two pulse generators.
*) the voltage and thus the resulting current

0098 8 5/0 458

BAD OWGlNAt

Robert Bosch GMBH . . R. 8996 Hb / Sz

Stuttgart. .

Of course you can; other pulse generators are also used, z. B. Blocking oscillators, tion of a capacitor begin to oscillate.

Instead of the contact 36, a circuit can also be used, as shown in FIG. As this circuit except of contact 36 is identical to the circuit of FIG only a part of the circuit according to -Fig. 1 shown.

In the circuit of Figure 5; the anode of the thyristor 14 via | the resistor 35 uncL the emitter-collector path of an npn transistor 60 connected to the negative line 29. The base of this' transistor is via a resistor 61 with; the negative line 29 and via a capacitor 62 to that connection of the contact 25 connected, which leads to winding 10 *

If the Koribakt 25 is open, the capacitor 62 is discharged. · If the contact 25 is now closed, a charging current flows to the Capacitor 62 and keeps transistor 60 conductive until the Capacitor 15 is charged as described above. If then the capacitor 62 is charged, the transistor 60 blocks. It works so like a timer.

It goes without saying that apart from those described or shown Modifications and further modifications are possible, since the inventive concept allows extensive variations.

Claims (1)

Robert Bosch GmbH '1O .R. 8996 Rb / Sz Stuttgart Expectations ! .Switching arrangement with a consumer that comes from a direct current source via a first thyristor with pulse-shaped Direct current is fed, with the quenching of the first thyristor a second thyristor is provided ,, and with min- " at least one pulse generator to control the two thyristors, characterized in that a first pulse generator (16) for controlling the first thyristor (13) and for controlling the second Thyristor (14) a second pulse generator (17) is provided so that when the first thyristor (13) is blocked, the first pulse generator (16) the second pulse generator (1?) blocked, and that for both pulse generators (16, I?) A common actuator (22, 23) is provided is. . 2. Switching device according to claim 1, characterized in that the first pulse generator (16) is blocked when the ers _(te thyristor (passes 1-3). 3 · 'Switching device according to claim 1 or 2, characterized in that that the actuator (22, 23) when adjusted, the duration of the pulses supplied by the individual pulse generators (16, 17) opposite adjusted. - 2 - New documents (Article 711 ai ». 2 No. 1 s.tz 3 of the Än * rungeaw. V. *. 9. 0098 8 5/04 5 8 bad ORiGiMAt Robert Bosch GMBH . * W. "R. 8996 Rb / Sz Stuttgart 4. Switching arrangement according to at least one of claims 1 to J, characterized; that both pulse generators (16, 1?) each contain a capacitor (43 or * 48) in a manner known per se, the charging current of which is adjustable and that of a certain Charging voltage the delivery of an ignition pulse by the pulse encoder controls, and that the charging currents of the two capacitors are adjustable in opposite directions in such a way that an increase ^ of the one charging current corresponds to a decrease in the other charging current and vice versa. 5- switching arrangement according to claims 3 and 4, characterized in that a common adjusting potentiometer (22) is provided as the actuator for setting the charging currents, with an adjustment of the potentiometer tap (23) increasing a resistance in a charging circuit (22, 44, 43) and the reduction of a resistance in the other charging circuit (2. ^J , 4 '>, 48) or vice versa. . i 6. Switching arrangement according to claim 4 or 5, characterized in that that the charging current of a stabilized voltage source - Zener diode (39) - is taken. 7- switching arrangement according to at least one of claims 4 to 6, characterized in that the pulse generator (16, 17) in itself as is known, each contain a two-base transistor (18 or 19), which becomes conductive at a certain voltage level on the associated cond.onaaLor (43 or 48), this condenser 00988S / 04B8 Hobert Bosch GmbH * Mf R. 8996 Rb / Sz Stuttgart Sator- discharges and thereby an ignition pulse to the one assigned to it Thyristor emits. 8. Switching arrangement according to at least one of the preceding claims, characterized in that ZTir deletion of the first Thyristor (13) with the help of the second thyristor (14) a capacitor (15) is provided, which is charged with the help of a transformer (28) depending on the current in the first thyristor, and that a switch (36; 60; 65) is provided which at least when the switching arrangement is switched on, a circuit closes in parallel with the second thyristor (14). 9 · Switching arrangement according to claim 8, characterized in that the circuit includes a resistor (35). 10. Switching arrangement according to claim 8 or 9, characterized in that that the circuit is only closed for a short time when switched on will. - ■ 11. Switching arrangement according to claim 10, characterized in that the emitter-collector path of a transistor in the circuit (60; 65) is arranged, and that the base of this transistor when switching on a short current pulse is supplied, which makes this transistor conductive. - 4 0 0 9 8 8 5 / (U 5 8 BAD ORIGINAL Robert Bosch GMBH . · ■ '? * ■ R. 8996 Rb / Sz - Stuttgart - "_ ·. ■ -" -. ■. 12. Switching arrangement according to at least one of the preceding claims, characterized in that the consumer is the electromagnetic winding (10) is an eddy current brake and that too this winding (10) in a known manner a diode (26) 'is held in parallel, which when the first thyristor (13) takes over the current (i) in this winding (10) .: 15. Schaltanordnimg according to claim 12, characterized in that ' the eddy current brake (10) installed in a motor vehicle is and that the actuator is a brake pedal (11) of this motor vehicle serves. · ■ -., . Stop arrangement according to one of Claims 4 to 13, characterized in that marked that as. Actuator provided two transistors one of which is to adjust the charging current for one pulse generator (16), another to set the Charging current at the other pulse generator (1?) Is used. BATHROOM OBlGINAL ÖQ908S / O45