DE1123569B - Control device for an auxiliary motor vehicle clutch - Google Patents

Description

Control device for a power-operated motor vehicle clutch The subject of the main patent is a control device for a power-assisted device Motor vehicle clutch with a pressure medium that transmits the auxiliary power, in particular Suction air required for the start-up process depending on the engine speed and for the shifting of the change gear depending on the movement of the gear shift lever is controlled by at least one valve, which is designed as a switching valve and the clutch or its servomotor is in one position with a pressure medium source, like the suction pipe of the prime mover and / or a vacuum tank, and in the other position connects to a space containing the bypass pressure, and with a valve that controls the flow of pressure medium when the clutch is engaged for the first, rapid one Stage of the multi-stage coupling process and a throttle opening bypassing this valve for the second, slow stage of the coupling process. Thereby are the switching valve to control the pressure medium flow when disengaging another valve for rapid Disengage as well as a throttle opening arranged parallel to this for the slow one Upstream disengagement.

During the slow disengagement process, when lowering the engine speed below a certain value, the clutch releases only slowly, so that for the Vehicle occupants do not experience unpleasant impacts that are harmful to the drive system. If, however, the vehicle quickly comes to a standstill, especially in the event of an emergency braking braked, the case may arise that not for the disengagement process enough time is available for its full process and the engine will stall will.

In the case of a control device for a power-assisted motor vehicle clutch it is already known per se to release the clutch when the driving brake is actuated. The clutch can only be disengaged when the engine speed falls below a certain level another known control device. With all of these control devices however, the clutch is always disengaged quickly, regardless of whether the driving brake is applied or is disengaged due to the impulse of another switching device.

The invention is based on the object of these disadvantages with simple Means to avoid.

The invention consists in a control device according to the main patent in that switching means are provided in a manner known per se, which when actuated the driving brake also control the valves that cause rapid disengagement.

In a further embodiment of the invention, in a control device, in which the disengagement processes on the one hand lead to the slow process of one through a motor speed dependent contactor controlled circuit and on the other hand in addition to a standing switch controlled circuit can be triggered in a known per se Way a dependent on the driving brake actuation switch, z. B. one from the circuit of the stop light actuated contactor, the engine speed-dependent circuit to the circuit from the one connected to the gear shift lever Switch is controlled.

It is particularly advantageous to use the one that is dependent on the actuation of the driving brake Switch in a manner known per se parallel to that with the gear shift lever to arrange related switch, whose circuit is known per se Way via the speed-dependent switch in one of which is below the switching value switched on position closes.

The features of the invention relate exclusively to a control device according to the main patent. An independent protection for the subject of the invention is not claimed.

In the drawings are exemplary embodiments of the control device shown according to the invention. 1 shows a schematic representation of the Control device for a power-operated motor vehicle clutch according to the invention and FIG. 2 shows a different electrical circuit of the control device according to FIG. 1.

The structure of the control device for a power-operated clutch shown in the figures is as follows: The clutch operating lever 1 is connected to the piston of the servo motor 3 via the connecting rod 2. Line 4 is located between servomotor 3 and control valve housing 5. Lines 6 and B also open into control valve housing 5. Line 6 connects control valve housing 5 to the intake manifold of the motor, which is not shown. The line 6 is separated from the interior of the control valve housing by the check valve 7. The line 8 leads from the control valve housing 5 to a vacuum tank 9 in which the vacuum is stored in order to be able to operate the clutch even when the engine is not running. The control valve housing 5 contains the valve 20; the switching valve 10 and the reducing valve 14 in parallel with the reducing valve 14, the throttle opening 12, and parallel to the valve 20. The throttle opening 18th The reducing valve 14 is actuated by the solenoid 17, the switching valve 10 by the solenoid 11 and the valve 20 by the solenoid 19. The interior of the control valve housing 5 is in communication with the outside air via the opening 16. The filter 15 is intended to prevent dust from entering the interior of the control valve housing. One pole of each of the electromagnets 17, 11 and 19 is connected to the electrical collector 27 via the ignition switch 28. The second pole of the electromagnet 19 is connected to the ground of the vehicle via the switch 23 'in the gear shift lever 23. The second pole of the electromagnet 11 can be connected to the ground of the vehicle either via switch 22 or via switch 24. The switch 22 is actuated by the alternator 21, depending on the voltage of the alternator, ie on the engine speed. The switch 24 is acted upon by the switch 23 ′ in the gear shift lever 23. The respective poles of the electromagnets 19 and 11 that are not connected to the ignition switch can be connected via a line and the contactor 30. This contactor 30 is acted upon by the circuit for the stop light actuation, ie, as soon as the stop light 31 is actuated by the stop light switch 32, the connection between the electromagnets 19 and 11 is established and thus both are actuated at the same time. The second pole of the electromagnet 17 can be connected to the ground of the vehicle via a contact switch 25 which is actuated by the accelerator pedal 26. The tension of the counter spring on the reducing valve 14 can be adjusted from the outside by means of the screw 13, depending on how the clutch process is to be accelerated by actuating the accelerator pedal. In Fig. 2, another possible variation for the circuit is shown. The switch 29 combines the switches 22 and 24 of FIG. 1 in one component. This arrangement is therefore; something easier.

The mode of operation of the embodiment shown in the figure results from the following: One can essentially differentiate between four operating states in the control device for the clutch. These are: 1. Starting from standstill and engaging by increasing the engine speed, 2. Disengaging for the purpose of gear shifting f while driving, 3. Disengaging by decreasing engine speed, _ 4. Disengaging when suddenly braking to a stop. To 1. If the vehicle is in the parking position, the ignition switch 28 is open and the electromagnets 17, 11 and 19 are de-energized. As a result, the servomotor 3 for the clutch actuation is ventilated through the throttle opening 12 and the opening 16 and the clutch is closed. If the ignition switch 28 is closed, the electromagnet 11 receives current via the switched-off switch 22 and the ignition switch 28, and the switching valve 10 is opened. This switching valve 10 simultaneously closes the connection to the throttle opening 12, and as a result the servomotor 3 and the vacuum container 9 are connected to one another via the throttle opening 18 and the opening of the switching valve 10 and the line 4. The clutch is released. If you want to start now, the motor is brought to a higher speed. The alternator 21 supplies a higher voltage current and the switch 22 is energized. As a result, the connection between the electromagnet 11 and the ground of the vehicle is interrupted and the electromagnet is de-energized. The switch valve 10 is pushed back onto its seat by the spring and the connection between the vacuum container 9 and the servomotor 3 is released. The servomotor 3 is now connected to the outside air via the line 4 and the throttle opening 12 and the opening 16. When the accelerator pedal 26 is actuated, the contact switch 25 is closed and the reducing valve 14 is opened by the electromagnet 17. This results in faster ventilation of the servomotor and quicker engagement of the friction clutch, which is necessary in order to prevent the motor from revving up inadmissibly when accelerating and to achieve rapid start-up. Regarding 2. If you want to switch to another gear while driving, the driver actuates the gear shift lever 23. The switch 23 'is closed and the switch 24 is energized; whereby the electromagnet 11 is connected to the ground of the vehicle and thus energized and the switching valve 10 creates a connection between the servo motor 3 and the vacuum tank 9. At the same time, by closing the switch 23 ', the electromagnet 19 is also energized, so that the valve 20 is also opened and in this case the vacuum container 9 is connected to the servomotor 3 not via the throttle opening 18, but via the valve 20. Through this connection between the servomotor 3 and the vacuum container 9, the servomotor is acted upon by the vacuum and the friction clutch is released via the clutch actuation lever 1. When the gear shift is ended, the gear shift lever 23 is released by the driver and the switch 23 'is opened. As a result, the electromagnets 19 and 11 are de-energized and the connection between the vacuum container 9 and the servomotor 3 is interrupted. The coupling process takes place as when starting (see FIG. 1) as a function of the actuation of the contact switch 25 by the accelerator pedal 26.

To 3. If the engine speed falls below the speed at which the clutch is engaged takes place by actuating the switch 22, then this falls off, and the clutch is achieved in that via the switching valve 10, the vacuum container 9 with the servo motor 3 is connected. In this case the connection is made between the vacuum tank 9 and the servo motor 3 through the throttle opening 18; the a too rapid access of the negative pressure from the negative pressure container 9 to the servomotor 3 prevents and thus causes a slow disengagement. That slow disengagement is necessary for different driving conditions in order to prevent the clutch from swinging.

To 4. In the event of a sudden stop braking, the speed of the motor drops also below the coupling speed and thus causes the effect described under point 3 Disengage by operating the servomotor 3. Deceleration of the disengagement through the throttle opening 18 is extremely undesirable in this case, since it it can happen that the engine stalls because the disengagement process is too strong is delayed. About the delay in clutch actuation when the vehicle is braked to avoid, is therefore between the electromagnets 19 and 11 a connection provided, which can be closed by the contactor 30. This contactor 30 is arranged in the same circuit as the stop light and is therefore used in the Actuation of the brake closed. In this case, the electromagnet 19 also receives Current as soon as the speed of the motor is below the clutch speed, regardless of whether the gear shift lever 23 is operated. The valve 20 is so opened and thereby the servomotor 3 with the vacuum tank 9 not over the throttle opening 18, but connected directly to the valve and a delay the disengagement process avoided.

The operation of the arrangement according to FIG. 2 is the same as that of FIG. 1 is only shown in FIG. 2 instead of the two switches 22 and 24 only one switch 29 is arranged.

Claims (3)

PATENT CLAIMS: 1. Control device for a power-assisted motor vehicle clutch with a pressure medium that transmits the auxiliary power, in particular suction air, which is controlled by at least one valve for the start-up process depending on the engine speed and for switching the change-speed gearbox depending on the movement of the gear shift lever Reversing valve is formed and connects the clutch or its servomotor in one position with a pressure medium source, such as the suction pipe of the prime mover and / or a vacuum tank, and in the other position with a space containing the bypass pressure, and with a valve that controls the pressure medium flow when the clutch is engaged for the first, fast stage of the multi-stage coupling process and a throttle opening bypassing this valve for the second, slow stage of the coupling process for rapid disengagement and a throttle opening arranged parallel to this are connected upstream for slow disengagement, according to patent 1 104 357, characterized in that switching means are provided in a manner known per se which, when the driving brake is actuated, additionally produce the valves (20) which cause rapid disengagement. steer. 2. Control device according to claim 1, in which the disengagement processes are triggered on the one hand for the slow sequence of a circuit controlled by an engine speed-dependent contactor and on the other hand for the fast sequence in addition by a circuit connected to the gear shift lever, characterized in that a in on known way of the driving brake actuation dependent switch, z. B. a from the circuit of the stop light (31) operated contactor (30), the engine speed-dependent circuit connects to the circuit controlled by the switch (23 ') connected to the gear shift lever (23). 3. Control device according to the claims 1 and 2, characterized in that the contactor dependent on the driving brake actuation (30) in a manner known per se parallel to the one with the gear shift lever (23) related switch (23 ') is arranged and its circuit in on in a known manner via the engine speed-dependent switch (22 or 29) in its a position switched on below the switching value closes. Considered References: French Patent No. 802 210; U.S. Patent No. 2 622 711.