DE2231715A1 - DRIVER CIRCUIT FOR A CLUTCH OR THE LIKE - Google Patents

Description

Driver circuit for a clutch ο «the like«

The invention relates to a driver circuit for a clutch or the like _β device.

Electric clutches, brakes, solenoids and similar devices work by storing energy in the form of an electric current, building up a voltage in a coil flows through and is used to carry out a mechanical function «. As a result of this energy storage, the Coil magnetizes, i.e. energizes, while the clutch remains actuated, with the coil usually having residual magnetism maintains and builds up after the current flow has ended and the clutch has been de-energized. This residual magnetism can build up to a value at which the time required to deactivate the clutch, brake, solenoid or the like. is required after the current flow through the coil has ended, is shortened considerably.

Another difficulty with such devices is that of causing or collapsing the magnetic field required instantaneous value of the current must be significantly greater than the required normal working current

209883/0710

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Output currents often cause burning, pitting, and general deterioration of conventional electrical Contacts emerge when such contacts are used to break and close the current path across the load «, These Deterioration increases even more at high switching speed, whereby finally the physical speed, with which the contacts can be safely opened and closed, which limits the speed with which the clutch, coil or brake can be alternately actuated and deactivated.

The invention is therefore based on the object of providing a supply or driver circuit for the aforementioned electromagnetically to create actuating devices, with the help of which high switching speeds between excitation and de-excitation are achievable and with the devices, · such as clutches and the like., mechanical functions to be effected can be carried out without a remanence delay.

The invention consists in a novel driver circuit in which an excitation coil, while it is de-energized, a small counter bias is ensured, so that the coil is demagnetized. This is done in a preferred Embodiment of the invention by arranging a Variable resistor circuit in series with the coil, so that the series connection forms a load. The resistance circle, the preferably consists of a resistor connected in parallel with a diode, shows a first resistance value when the current flows through the combination in a first direction so that the diode shunts the resistor and the coil is energized, and has a second resistance value when the current reverses the combination flows through, so that the diode is switched off and a

209883/0719

a small counter bias sufficient for demagnetization is guaranteed across the coil.

In the embodiment of the invention described below, this current direction reversal is preferably carried out by an electronic circuit that can excite and de-excite the coil much faster than mechanical contacts and which comparatively large currents or powers with comparatively low power consumption safely. to able to switch. Two electronic switches are connected to each other, with an input driver circuit, a DC power source and connected to one side of the load · When the input driver circuit receives a first signal, one of the electronic switch applies a low voltage to one side of the load to which it is connected while the other electronic switch impresses a high voltage on the side of the load connected to it. If then the Input driver circuit receives a second signal, the polarity of the voltage across the load is reversed, Whenever the coil is traversed by an exciting current, a transition voltage is generated across the coil, which lets it tighten quickly and, in the event of a clutch, ensures safe and quick engagement.

In the following a preferred embodiment of the invention is explained in more detail with reference to drawings. Show it:

1 shows a block diagram of a circuit with the features the invention,

Fig. 2 is a detailed circuit diagram of the circuit of Figure 1 and _e

209883/0719

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FIG. 3 is a graphical representation of the process shown in FIG voltages occurring across the coil

1 shows a block diagram of an embodiment of the driver circuit according to the invention. As mentioned, this circuit has an electronic switch driver stage 20 which - either on separate lines or on the same line - is able to receive at least two input signals. Upon receipt of the first input signal, the driver circuit generates a suitable signal which is fed to an electronic switch 22 connected to the driver stage 20 in the manner shown, so that the latter generates at least a considerable part of the voltage of a conventional direct voltage source 2Zf, which for example has a direct voltage of 150 V supplies, is applied to a terminal A of a load 26, which preferably consists of at least one coil 30 of an electrical coupling, a magnetic coil or a similar device, through which current flows to generate a magnetic field and store energy, which is then used to carry out a mechanical function is used. The coil 30 has a variable or regulating resistor J> 2. connected in series, which has a first resistance value when the current flows through it in one direction and shows a different resistance value when the current flows through it in the opposite direction.

The electronic switch 22 is, as is the switch driver stage 20, connected to a second electronic switch 3Zf, so that when the switch takes a considerable part of the voltage supplied by the voltage source 2Zf depending on the receipt of a first input signal by the driver stage 20 is applied to terminal A, the electrical

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tronic switch 3k applies a voltage to the terminal B which is lower than the voltage applied to the terminal Λ, so that the current flows through the load 26 in the direction indicated by the arrow 38. The two electronic switches 3k and 22 are connected to ground via a resistor l \ O , so that the voltage which the switch 3k applies to the terminal 3 when the driver stage 20 receives the first input signal, by directly connecting the resistor AfO to the Terminal B can be generated.

As a result of the normally considerable inductance of the coil 30, at the time of the switching process in the direction of the Arrow 38 through the load 26 current is quite large and generates a sharp voltage pulse across coil 30, so that then the magnetic field builds up quickly and enough energy is stored in order to be able to perform the mechanical function quickly. In those cases where the coil is 3 ° one Clutch is assigned, this transition pulse causes a rapid engagement of the clutch · It has been surprising shown that by such a mode of operation service life and reliability of the clutch compared to the most arrangements in which it is not indented so abruptly can be significantly improved.

The current flow through coil 30 in the direction of arrow 38, which continues during the idle state period with voltage across coil 30, is large enough to perform the desired mechanical function. When the second input signal is then applied to the electronic switch driver stage 20, a signal is generated and impressed by the driver stage 20 on the electronic switch 3k , so that the latter applies a voltage to the terminal B which represents a considerable part of that supplied by the voltage source Zk Represents tension. At the same time, the switch 22 is

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let on. apply a voltage to terminal A that is significantly lower than the voltage applied to terminal B, so that the polarity is reversed via the load 26 and the current flows through the load 26 in the opposite direction to the arrow 38 begins.

As mentioned, however, the cone resistance is ^> 2. designed so that he latter to the position indicated by the arrow 38 Hichtung high when a current flows in the opposite direction and a low i / besitzte ifiderstandswert when current flows in .Direction of arrow 38. However, a sufficient return current through load 26 and the coil 30> flows ^around a To apply this demagnetizing small counter-bias voltage, as mentioned, this demagnetization takes place every time the direction of current flow is reversed, so that the deceleration due to a magnetized coil is eliminated after the current flow has ended.

FIG. 2 shows a detailed circuit diagram of a circuit for performing the functions of the circuit shown in block diagram form in FIG. 1, while FIG. 3 shows the voltage across the two coils actuated by the circuit according to FIG. In the embodiment shown, the driver stage 20 has a transistor 50, the base of which is connected to an input terminal 3k via a resistor 52 and is also connected to ground via a resistor 56. When the input terminal 5k is essentially at ground potential, so that the transistor 50 switches through the voltage applied between its base and its emitter and is impressed by the transistor 60 and controls it into the saturation range, the saturated transistor 50 applies a low voltage "Essentially at ground potential" voltage across a resistor 63. the base of a transistor 62, so that it is held in the blocking state. Since the transistor 62 blocks, a high voltage

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Voltage applied to the base electrodes of transistors Gk and 66, so that the latter are driven far into their saturation range and therefore effectively ground potential is applied to the collector of transistor Sk and to the collector of transistor 66 via resistor 1 + 0. Since the collector of transistor 66 is essentially at ground potential, transistor 68 is held in its blocking state. Furthermore, the collector of the transistor 6 * t is connected via a resistor 69 and a line 71 to the base of a transistor 70, so that the transistor Gk applies an input signal corresponding essentially to ground potential to the base of the transistor 70, whereby the latter is held in its blocking state will. The base of a transistor 72 is connected to the collector of the transistor 70, which is connected to the power supply line 75 via a resistor 7k , so that the transistor 72 conducts when the transistors 70 and 68 are both blocked and a high voltage is applied to the B terminal the load 26 applies. As shown, the feed line 75 is connected to a conventional direct current source 2.k , which has full-wave rectifier diodes 77 », a fuse 79 and a smoothing capacitor 81.

The base of the transistor 7A- is similarly connected to the terminal B via a resistor 76 so that when the terminal B is at high voltage and the transistor 6 ^ + is on, a voltage between the base and emitter of the transistor 7k is applied, which brings the latter into the saturation region, whereby the base of the transistor 80 is essentially connected to ground via the resistor ZfO, so that the transistor 80 remains in its blocking state. In this way, a voltage of a first polarity appears between terminals A and B, so that the current flows through the load in the opposite direction to the direction of arrow 3o. A capacitance ΰ'2 is attached to the collectors, the transistors 72 and 80

209ß83 / 0719

concluded that prevented the tension at that point breaks down too quickly when the electronic switches containing these transistors are out of their first in theirs second output state switch to the polarity of the voltage across the load 26 and the direction of current flow through it To reverse the burden

If the terminal B, as mentioned, is at a higher voltage than the terminal A, the current flows in the opposite direction of arrow 38 through the load and in particular through a first Circuit consisting of a parallel connection of a resistor 86 and a diode 88, which is connected to a clutch coil are connected in series, as well as by a second circuit consisting of a further parallel connection of a resistor 9Zf and a diode 96 connected to another clutch coil 100 are connected in series. The resistor 86 and the diode 88 form a variable resistance element, which is a comparative has a low resistance value when the current flows through the load 26 in the direction of the arrow 38 and diode 88 shunts resistor 86. Conversely, if the current is opposite to the direction of the arrow 38 through the resistor 86, the diode 88 and the clutch coil 90 flows, there is no current flow through it in its blocking state biased diode 88 present, so that the offered by the parallel connection of resistor 86 and diode 88 Resistance value is considerable. When current flows through the load 26 in the direction of the arrow 38, that is accordingly 3, the voltage drop occurring across the clutch coil 90 is essentially the voltage drop across the terminals A. FIG and B of the load 26; If, on the other hand, the current flows in the opposite direction, then the current that occurs with opposite polarity is Voltage drop across this coil 90 is a fraction of that.

2 0 9883/0719

The circuit is designed so that when the current flows in the seal of the arrow 38 and the voltage across the coil 90 essentially the voltage between terminals A and B. corresponds to the load 26, the energy stored by the coil is sufficient to perform its mechanical function. Flows on the other hand, if the current is in the opposite direction, the voltage across the coil 90, as mentioned, is just sufficient to demagnetize this coil. A resistor 10Zf and a neon lamp 106 are connected in parallel with the clutch coil 90 and are used for Display when the coil 90 is in operation or is energized.

Similarly, a second coil 100 is connected in series as shown with a resistor 9 ^ f and a diode 96, so that the parallel connection of resistor 9 ^ f and diode 96 when the voltage at terminal B is the same at the terminal A exceeds / has a comparatively low resistance value, since the diode 96 essentially shunts the resistor ^ L · _S ■ , so that the voltage across the second coil 100 practically corresponds to the voltage between the terminals A and B and that of the coil 100 associated clutch is actuated to carry out its mechanical function. If the current flows in the direction of arrow 38 through the load 26 and the voltage at terminal A exceeds that at terminal B, the resistance of the parallel connection of resistor 9 * f and diode 96 is considerable, so that a small residual voltage across the Coil 100 results in the opposite polarity and sufficient to demagnetize the coil. In the special embodiment according to FIG. 2, the two coils 90 and 100 are alternately excited and demagnetized, ie one coil is demagnetized while the other is excited. This special arrangement has proven to be particularly advantageous for the actuation of the clutches known as gap and bead couplings, which are used for the production of beaded yarn in spin

-10-209ßK3 / fl719

are used. The details of such a device are in the patent application ··. ·. ·· .. ···· of the same Day explained in more detail. With the load 26, a variable or conical resistor 110 is connected in Heine, which is used to change the current flow across the load is used to any desired value «,

If a second signal is applied to the ÜLngangs-Klemme 5 * t, which has a high value compared to Hasse, the transistor 50 is switched to its blocking state and consequently a high voltage is applied to the base of the transistor 62, which then turns on and the ground potential to the Base of transistor 66 and transistor 6 ^ f applies. This blocks these two transistors. When the transistor 66 is switched from its on into its off state, a high input signal is applied to the base of the transistor, the emitter of which is connected to ground via the resistor i * 0, so that the transistor 68 turns on and a low input signal which is essentially at ground potential Apply voltage to terminal B. The voltage at Kleftme B is impressed via the resistor 76 on the base of the transistor 7k , so that the latter is also switched to the blocking state, whereby the transistor 80 can turn on and apply a high voltage to the terminal A.

In a corresponding manner, a high voltage is now applied via line 71 and resistor 69 to the base of the transistor 70 applied so that the latter switches through and thereby the transistor 72 can block. The current now flows over the Load 26 from terminal A to terminal B via transistor 80, the transistor 68 and the resistor ifO ·, Der to the terminals A and B applied current is therefore the same in each case, only the polarity of the voltage across the load 26 has changed.

-11- 209BB3 / n? 13th

Control input terminals 120 and 122 can be used to hold the circuit in one of its output states regardless of the input signal applied to terminal 54. If, for example, a high input signal is applied to terminal 122, this input signal remains the input signal to the base of transistor 62, regardless of whether transistor 50 is subsequently turned on in response to a low input signal at input terminal ^ k or not . When a high input signal is applied to the control input terminal 120, a transistor 123 is switched on accordingly and essentially applies ground potential to the input of the transistor 62, so that the latter remains in the blocking state.

Although, as mentioned, this circuit proves to be particularly advantageous for controlling the operation of clutches used for the manufacture of beaded yarn this circuit can be used in a variety of other uses to control any of numerous various devices, such as clutches, brakes, etc., are used in which a coil ο »the like. more fluent Electricity is used to store energy in a magnetic field and this energy to carry out a mechanical one Function. For example, the circuit according to the invention has also proven to be particularly advantageous for the actuation of the feed switch on a Dr apier st ο ff cutting table proven in which the circuit is actuated by a push (button) switch to an electric clutch to activate, which feeds a piece of cloth of predetermined length to the cutting table. Once reached the predetermined length is, the circuit is switched by a photocell unit, so that the clutch drops or disengages and 'acts as a brake. It has been shown that the quick switching properties the circuit according to FIG. 2, the accuracy

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control compared to conventional, so far Relay switches used in cutting table controls are significantly improved.

It has also been shown that the circuit according to the invention in comparison to the switching properties of known microswitches and relay ensures a very fast switching process, both because of the comparatively high transition voltage, which is applied to the coil to excite it, as well as because of its low, reversible polarity Voltage that is applied to the coil to demagnetize it when the circuit is not actuated. Still has it has been shown that this circuit has a pulse voltage of up to 15% of the working voltage when switching brakes, Clutches and solenoids supplies, which allows a faster magnetic field build-up and higher operating speed of the device possible are. Of course, this circuit has no moving parts and can be seen to eliminate the switching current problems caused by the stored energy without damage.

In the circuit diagram of Figure 2, there are certain exemplary values indicated for the individual components, but the invention is in no way intended to be restricted thereto.

In summary, the invention thus creates an electronic driver circuit for a clutch or the like. Contraption,, in which the clutch coil with a variable resistance circuit, such as a parallel connection of diode and resistor, is connected in series, which has a first resistance value when the current for actuating the clutch in which flows through the series circuit in one direction, and has a second, larger resistance value when the

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Current in the opposite direction through the series connection flows, so that a small counter bias is generated across the coil, which demagnetizes the coil and thus their speed of response when de-energizing the same increases. Two electronic circuits are connected to the load, to reverse the polarity of the voltage across the load and, accordingly, the clutch as a function to operate and demagnetize alternately from input signals. At the time of coil energization becomes a high Transition current generated, which ensures a quick response of the clutch. In the embodiment shown, the load consists of two alternately connectable coils each with a variable or constant resistance connected in series with them, so that one coil is excited while the other is demagnetized, and vice versa

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Claims (2)

Claims 1. Driver circuit for an electromagnetic device whose mechanical Funistion is triggered when the at ^ iStromstrom stored electromagnetic energy exceeds a predetermined value, characterized by a with at least one partial winding of the device in series with a variable resistance circuit with a first resistance value when a given voltage across the series circuit consisting of the circuit and the winding has a first polarity and such a potential build-up that the flowing through said series circuit Electricity is sufficient to store enough energy to carry out the work function, and with a second, larger one Resistance value when a given voltage across said series circuit is opposite in polarity and has such a potential build-up that the flowing in the opposite direction through this series circuit Electricity is not able to store enough energy to carry out the work function mentioned, and by a with the circuit and the winding connected source, which upon receipt of a first input signal, the predetermined The voltage of the first polarity builds up across the series circuit mentioned and thus excites the dedication and continues to do so when a second input signal is received, the predetermined smaller voltage of opposite polarity is transferred the mentioned series connection is generated and thus the winding is demagnetized. 2. Driver circuit according to claim 1, characterized in that the circuit consists of a resistor and a resistor connected in parallel therewith There is a diode that conducts current when the specified voltage of the first polarity is applied to the series circuit from circuit and winding of the device -V) - 209B83 / 0719 «AD is applied, and does not conduct any current if the specified voltage of opposite polarity to the said Series connection is created o 3. Driver circuit according to claim 1, characterized in that the device is an electromagnetic clutch / fe driver circuit according to claim 1, characterized in that that with another part a further electromagnetic device is connected, with a second resistance variable Circuit is in series that this series circuit and the other part in parallel with the former Series connection of the first circuit and the first winding are connected that the second circuit has a first resistance value when the predetermined voltage across the second series circuit and the other Part has the second polarity, so that in the opposite direction through the series connection and the other part a to Performing the work function sufficient current flows, and has a second, larger resistance value, if the predetermined voltage across the second series circuit and the other part besüzt the first polarity, so that the current flowing through these sections in the former direction does not have enough energy to carry through the work function is able to store, and that the source, the predetermined voltage of the first polarity over the Series connection of the other part and the second circuit provides when the first input signal is received, so that a voltage of the first polarity is generated across the other part and this part is demagnetized in the process, and upon receipt of the second input signal. ^ the predetermined voltage of the opposite polarity to said Series connection creates, so that then a larger -16-209883 / 0719 Voltage of opposite polarity across the other part generated and this part is magnetized. 5. A circuit according to claim 1, characterized in that the source supplies a DC voltage that an electronic switch in a first switching state at least part of the DC voltage to one side of the series connection of circuit and winding and to its second Switching state a lower voltage on this one side switches on that a second electronic switch in its first switching state at least part of the DC voltage to the other side of the series circuit mentioned and in its second switching state a lower voltage switches on to this other side and that with A third electronic switch is connected to the two electronic switches, to which the two input signals can be fed, and which is when the first input signal is received the first switch from its first to its second and the second switch from its second to seüren the first state and upon receipt of the second input signal the first switch from its second to its lets the first and second switch toggle from its first to its second state 6 · Driver circuit according to claim 5> characterized in that a variable or «, regulating resistor with the series connection the winding and the circuit are in series, 7 · Driver circuit according to claim 5> characterized in that each electronic switch has at least one having a single transistor. ο «, method for! actuation of electromagnetic devices, in which an electric current flows over a section, -17-209 883/07 19th so that in this electrical energy to carry out a mechanical function when the stored energies exceeds a predetermined value, is stored, characterized in that a voltage a first polarity is built up over a device part, so that current flows through this and energy is saved so that the device can function can perform, and then a voltage of much smaller value and of opposite polarity is applied to demagnetize the device part 9 ·· The method according to claim 8, characterized in that a voltage of the first polarity and of smaller Value across another part of another device is applied to that part simultaneously with the Applying the voltage of the first polarity to the first part to demagnetize, and then a voltage of the opposite polarity is applied across the other part to store energy and the other device to have their work function carried out at the point in time at which the voltage is opposite Polarity is applied to the first part » 2 0 Π HH 3 / Π 7 1 ί)