WO1990007438A1

WO1990007438A1 - Control device for the automatic actuation of vehicle clutches

Info

Publication number: WO1990007438A1
Application number: PCT/HU1989/000066
Authority: WO
Inventors: János PUGLITS; János VÁRADI; Attila Madocsay
Original assignee: Puglits Janos; Varadi Janos; Attila Madocsay
Priority date: 1988-12-23
Filing date: 1989-12-22
Publication date: 1990-07-12
Also published as: EP0401337A1; HUT52421A

Abstract

Control device for the clutch of vehicles designed to be actuated by a pressure medium, whereby the forked lever actuating the clutch is provided with a unit which operates with a pressure medium and which is controlled by electrically actuated valves. Said valves are actuated by an electronic control unit which processes the signals from: the switch provided on the forked lever, the switch unit detecting the position of the accelerator pedal, the switch sensing the no-load mode of the gearbox, the switch signaling the mechanical position of the clutch or the switch connected with the space containing the pressure medium, the signal transmitter whose signal shows the r.p.m. of the engine, and the signal transmitter whose signal shows the speed of the vehicle. The invention is characterised in that the pneumatic outputs of the electrically actuated valves (8, 9, 10) are connected with different throttles (11, 12, 13), and in that the electrical control inputs are connected with the outputs of the storage current circuits (24, 25) via power amplifiers (21, 22); the inputs of the storage current circuits are connected to a logic network (36) which is, accordingly, a storage system with a fixed program. The inputs of the logic network (36) are connected via the frequency-voltage converters (31, 34) and via the comparators with adjustable switching level to the signal transmitter (18) whose output signal shows the r.p.m. of the vehicle engine, and via the signal transmitter (33) which shows the speed of the vehicle by means of the electrical output signal, as well as via the receptor circuit (27, 28, 29, 43), on the one hand to the switch (14) provided on the forked lever, on the other hand to the switch (16, 17) detecting the position of the accelerator pedal, to the switch (42) showing the no-load mode of the gearbox, to the push switch (6) and to the switch (40) detecting the position of the forked lever (2) with the electrical output.

Description

CONTROL FOR AUTOMATICALLY OPERATING THE CLUTCH OF VEHICLES

The invention relates to an electronic control for automatic actuation of the clutch of vehicles, the traditional friction clutch with pressure medium containing, i.e. hydraulic or pneumatic cylinders is moved. As is well known, the driver must operate three pedals while driving, namely the accelerator pedal, the brake pedal and the clutch pedal, if the speed is manual. With automatic

The clutch pedal is not necessary, which has numerous advantages in terms of ergonomics and safety in traffic. (Such automatic change gears are described in the book Väradidr. Komändi: "Tractors, Cars", Ladnwirtschaftlicher Verlag, Budapest 1980). Experience gained in practice has shown that the known automatic change gearboxes are too expensive, with an average level of technical readiness they cannot be repaired, furthermore the gearboxes reduce the performance and economy of the vehicle. For the reasons mentioned above, with the exception of the United States, the automatic change gearboxes had only spread to a limited extent.

Experts have long been running experiments aimed at the automatic Release the traditional friction clutches. Numerous proposals aimed at the set goal are known, but none of them has spread widely. The reason for this is obviously that the special structural solution requires special knowledge both during commissioning and repair, and the operation also differs from the traditional one.

A construction for automatically actuating the clutch of vehicles is known from WO 88/04242. However, there is no sufficient control specified.

Our invention represents the further development of this known solution.

The above-mentioned invention relates to a device designed as an adapter, which has a pneumatic working element, in particular a membrane, which is actuated via the solenoid valves of the electropneumatic control unit. The inputs of the electropneumatic control unit form a logic network, which was created by the series connection of the electrical contacts of the accelerator pedal and the shift lever, which at the same time represents a signal generator with an output signal proportional to the number of revolutions of the engine.

The operation of the device described above is as follows:

When starting the vehicle without pulling the accelerator pedal, gripping the gear lever and out of the

When the basic position is tilted out, the electro-pneumatic control receives a signal via the electrical contacts of the series-connected basic position switch of the accelerator pedal and the shift lever, whereupon the solenoid valves receive the excitation current and the working diaphragm emphasizes the clutch. The highlighted position is due to the self-sustaining circuit of the switch operated by the valve stem. After the speed stage has been switched, when the accelerator pedal is depressed, the series-connected accelerator pedal or the gearshift lever separate, furthermore, as soon as the signal from the engine speed sensor reaches the threshold value of the occasion

Excitation is removed from the solenoid valve, at the same time the air is released from the work space and the clutch is closed.

In the sense of the invention, the final characteristic with the break point is through the solenoid valves

guaranteed, which are assigned to the various threshold values of the engine speed.

The deficiency of the above-mentioned solutions consists in the fact that the throttles are only set with a compromise for smoothly closing the clutch between the switchings of the lower gear stage at the start and the higher gear stage

can be. Another shortcoming of the above-mentioned solution is that the detection of the basic position of the accelerator pedal and the shift lever is only possible by simultaneous actuation, although there is a need to be able to detect the basic position of the accelerator pedal independently.

Due to this fact, this becomes primarily

Prevention of the engine brake operation is prevented, since in this way the permitted lifting of the clutch cannot be connected to a given position of the accelerator pedal, but only to a number of revolutions set via the basic run.

A further deficiency is that, when the engine of a vehicle is running and the gearbox is in a neutral position, the clutch is constantly in a raised position, which leads to premature ver wear of individual structural elements, e.g. the

Lever bearings leads.

The present invention has been aimed at eliminating the above-mentioned shortcomings, i.e. To develop a solution that can be retrofitted to every personal car and commercial vehicle, there should not be any need to adapt the device to different management styles, the driver should never feel the difference compared to the traditional expression of the clutch.

Our invention is based on the knowledge that, in the closing characteristic of the coupling, the sliding break point is detected by the direct or quasi-direct (pressure of the actuating pressure medium)

closing disks is determined, the closing speed of the clutch after and before the break point being determined from the speed of the vehicle or from the position of the accelerator pedal.

A further advantageous characteristic is shown in the fact that the control only allows the clutch to be lifted when the accelerator pedal is in the basic position, regardless of the number of revolutions of the engine. We have gained this condition from experience by using the occasion - especially for vehicles with a diesel engine. in the event of a higher load on the vehicle or on a slope, when the clutch is closed, the number of revolutions of the engine drops to a certain extent, which in turn leads to a further highlighting of the clutch. Another advantage of the above-mentioned is that the engine brake operation, which is essential from the point of view of traffic safety, can be implemented in this way.

By detecting the vehicle speed, it is possible to implement engine braking even at higher speeds. The set goal is achieved in such a way that the clutch cannot be released when the engine speed drops above a set speed (10 km / h), not even in the basic position of the accelerator pedal. In this higher speed range, the clutch only triggers

the actuation of the switches for the basic position of the accelerator pedal and the change gearbox.

A further improvement can be achieved in the function of the construction - especially in the case of fast starting cars with a petrol engine - in such a way that the set limit values for the number of revolutions when starting and taking off are shifted to a certain extent with respect to the direction of the change depending on the speed of the changed number of engine revolutions . In the case of a quick start, the set threshold of the revolution shifts

downward, with a rapid decrease in the number of revolutions of the engine, the threshold value of the revolutions of the

Choking moved upwards.

For the sake of good order, it should be noted that after a cold start, the function of the start button shifts the set limit values for the number of revolutions when starting, starting and lifting.

We went to solve the task

from the actuation structure of the automatic clutch described above, which is a pneumatic

Arbsitsorgan, in particular a membrane, a control cooperating with it, a retirement

of the accelerator pedal sensor, a sensor detecting the grip of the shift lever and one with

signal proportional to the number of revolutions

Has signal generator, wherein the control consists of electro-pneumatic valves.

The invention was further developed in such a way that an electronic control is used, the inputs of which with other, other parameters of the

Vehicle monitoring signal transmitters are connected, e.g. signaling device indicating the speed of the vehicle, the sensor for detecting the sliding point of the clutch, the position of the lifting

Fork-sensing sensor or the pressure switch that detects the neutral position of the change gear

Switches, the switching unit of the accelerator pedal - the switches which indicate the depressed state of the accelerator pedal and the ones which perceive the basic position

Switch is composed -, the outputs are connected to two pneumatically connected valves in series and the second valve is connected to at least one parallel third electropneumatic valve, from which the connection of the first valve of an air line, the other connection are connected to the air space of the membrane housing , furthermore the second and the third valve connected in parallel are each connected to the outer air space by means of a throttling, the second valve via the electronic control with the switch acting as the floating point and the third valve - likewise via the electronic control - with the signal transmitter, which signals the vehicle speed, is in control connection.

With the introduction of electronics, we were able to use electronic elements instead of mechanical switches when recording different positions, which are more resistant to environmental stress, work with increased reliability and accuracy. In this way, we have developed an opto-sensitive version for the gearbox switch, In the sensor that detects the raised-closed position of the clutch, we have installed a sensor with a Hall element that is actuated with a permanent magnet. In the version for buses, we have used an inductive proximity sensor to record the position of the accelerator pedal.

The subject of our present invention relates to a completely electronic, in principle modified control device. To solve the problem we started from the actuation construction of the clutch described above, which is a pneumatic one

Has working organ, a membrane and an electromechanical control unit cooperating therewith. Compared to the previously registered electromechanical design, the main development is that the introduction of electronics enables simultaneous detection and monitoring of several input parameters, e.g. the detection of the position of the accelerator pedal, the detection of the number of revolutions eliminates the need for two signal transmitters, and the electronics, based on the signals from the revolution counter, perform the

Separation of the thresholds.

Another significant change is shown in the fact that it is not a switch that detects the basic position of the accelerator pedal that controls the closing of the clutch, but rather the closing of the clutch due to the increase in the number of revolutions of the engine that is set or

can be modified, is started.

The logical network forms an essential element of the electronic control unit that is functional

is a pre-programmed memory, the input signals of which are the YES-NO signals coming from the encoder or the output signals of the comparator circuits, the latter being the threshold values of the changes in the number of revolution signals with analog signals Monitor character.

Another essential element of electronics are the storage circuits, which are capable of the states preceding the following function

perceive and use them to generate the logical decisions about which may be the same at the moment

Parameters belong, but are derived from the previous ones

Resulting states that the function of the clutch would require different output parameters. Such

The condition exists e.g. in the fact that when the clutch is closed, after the starting number of revolutions has been reached, such closing speeds can be generated for the clutch that correspond to the current driving circumstances of the vehicle, that with the control

of the valves with different throttles can be reached in the required order

can.

The invention is based on an advantageous

Embodiment, explained in more detail with reference to the accompanying drawings. Show it:

1 shows the block diagram of the electronic, electropneumatic, hydraulic elements of the control according to the invention, as well as the sensor and the signal transmitter,

Figures 2 and 3 show the version of part of the

Solution according to Figure 1, the one

Car has been adapted, in two views,

Figure 4 shows an expanded detail of part of the

Solution according to Figure 1.

2 and 3 represent the already realized

Execution of the version adapted for cars, with the control according to FIG. 1, with the pneumatically actuating membrane 5, the hydraulic actuating cylinder 4, the valve units 8, 9, 10, and with throttles 11, 12, 13.

In the passenger car, the pneumatic

Control made with the vacuum of the suction pipe.

The valve unit implemented on the bus

control pressure with an air pressure of 6 bar is supplied from the air tank of the bus.

In a car, the valve units 8, 9,

10 connected to the intake manifold via the air line 43.

According to the experience gained during the tests, the vacuum of the suction pipe is capable of anywhere

Depression of the required size (0.4-0.5 bar)

generate in the air space of the membrane housing 44, which ensures the operational safety of the device. The depression-dependent throttle valve 45 shown in Figure 3, connected to the valve unit, is well known from our previous solution, at

In the event of sudden accelerating, the clutch is closed as a result of the rapid vacuum removal.

Figure 4 shows the comparator circuit 32 with

the adjustable level, which processes the signal of the speed sensor 18, this version is ideally suited for adaptation in a car. In the known device determines the beginning of the excavation, for example. of

Closing the clutch except for the signal from the switch indicating the function of the change gear,

also the current value of the engine speed.

An essential element of our invention is that the signal from the rotation signal generator 18

after preprocessing comes to the input of the comparators with the adjustable switching level, the

Circuit level is modified, with that (not detailed in the figure) to the comparator 32

associated) control circuit with PID character, the

the number of revolutions and the dynamic change of the

Speed monitored. In this way it can be ensured that the opening or closing moment of the

Required switching level is corrected, both at the different accelerations of the clutch

Vehicle or with various gas supply (sporty comfortable driving styles).

The circuit arrangement works as follows: The controller 46 is a circuit made up of an operational amplifier, to the one input of which the static _one determined with the variable resistor P ₁

Voltage signal U _A , to the other input reaches the DC voltage signal U _F , which is proportional to the number of engine revolutions. The control acts on the voltage signal U _F. When the voltage signal U _F changes, the controller amplifier 46 changes the output voltage set with the basic signal U _{K as a} function of the changed speed. The output voltage U _K is the basic tipping signal of the

Hysteresis comparator, which is constructed from the operational amplifier V, the feedback resistor R _V and the variable resistance P2. The other input of the hysteresis comparator is a DC signal proportional to the engine speed. The modification of the basic signal U _{k brought} about by the controller amplifier is of such a sense that in the event of a rapid change in U _F the switching of the comparator constructed from the operational amplifier V is brought forward, that is to say that when the accelerator pedal is pressed in quickly and the start-up is rapid the engine is set for the occasion

Threshold of rotation downwards, if the engine speed drops rapidly, the limit value for lifting the clutch can be shifted upwards.

The switch K _SZ shown in Figure 4 is operated in the suction mode, the suction mode by the Voltage U _{SZ increases} the basic signals of starting or lifting, ie the value of the number of revolutions.

The switch K _SZ can be operated by hand or it is controlled by an electronic element.

The controlled electronic switch can be used primarily in vehicles with an automatic start button, the control system automatically tipping the switch into the suction position when the vehicle is started, monitoring the number of engine revolutions and, when falling, the number of revolutions of the basic run, which is characteristic of the heated engine , sets the switch K _SZ to normal operation.

The version already implemented here actuates the coupling of a bus. The device was built into a traditional bus with pressure

medium actuated clutch installed, in which the

dry friction clutch 1 with a lifting fork 2

is actuated with the aid of the hydraulic working cylinder, the latter being connected to the hydraulic actuating cylinder 4 connected to the pneumatically actuated membrane 5. The pneumatically actuated membrane 5 receives the actuating air required for lifting the clutch from the air container

7 via the electro-pneumatic valves, which consist of the valve units 8, 9, 10.

The electropneumatic valves are with the power amplifiers 21, 22, 23 of the electronic

Control unit controlled. The valves are switched pneumatically in such a way that at the same time

Actuation suddenly let the air into the housing of the actuating diaphragm 5, which ensures that the clutch 1 is quickly lifted out. When the clutch is left behind, the movement is divided into several speed sections; the conditions are determined by the various sensors and signal transmitters. If now the clutch 1 is closed

Gear is set, the control of the electropneumatic valve 8 stops first, the air supply from the air tank 7 stops, the air exits the actuating membrane housing via the throttles

11, 12, 13, which means that until the disks of the friction clutch start to close, rapid emptying takes place, after which depending on the pressure switch 6 or on the position-sensing circuit of the lifting fork 40, or in dependence the vehicle speed the process of the connection further accelerates, or by the gradual shutdown of the valve or

of valve 10, i.e. is slowed down by closing the throttles 12, 13. The ones that control the valves

Power supplies 21, 22, 23 are controlled by the storage circuits 24, 25, 26, the inputs of which

are formed by the logical network 36. The logical network 36 is expediently a logical element, expediently a permanently programmed memory circuit (EPROM or ROM). After the digitization of the corresponding encoders, the logical network 36 processes

or the analog signals from the input combination, the required signals actuating the valves, the combinations actuating the valves and from

which the control signals. The switch on the gear lever is used to deliver the input signals

14, which comes into operation when the shift lever is touched, the position sensor of the extracting fork 40, the

Pressure switch transmitter 6, the sensor of the switching unit

16, 17 of the accelerator pedal, the switch 42, which indicates the neutral position of the change gear, the position transmitter

38 of the brake pedal, and the transmitter 18 indicating the engine revolution with the electrical output signal,

expediently a tachometer dynamo, and the speed transmitter 19 with an electrical output signal,

expediently the signals of the tachometer dynamo; these control via the signal conditioning units

30, 33, via the frequency-voltage converter 31, 34

and the comparator circuit 32, 35 with adjustable switching level and adjustable hysteresis is the logical one

Network 36. The sinusoidal signals or pulse signals of the tachometer dynamo 18 indicating the motor revolution with the electrical output signal are in the signal receiving and conditioning circuit

formed, the square signals filtered in this way and brought to the corresponding signal level

the input of the frequency-voltage converter appears with a voltage level proportional to the input frequency. The voltage level of a comparator

Comparator unit 32 is set to the engine start speed during the voltage level

of the other comparator is set above a level that corresponds to the number of revolutions of the basic run.

If the starting number of revolutions is now exceeded, the comparator of the starting number of revolutions topples over and

brings about a change in the control signal on the output, for the logic network 36. Likewise, the other tilts over that of the number of revolutions

of the base run corresponding level set comparator when the number of revolutions changes from top to bottom and forms on its Ausgeng an input signal for the logic network 36 for canceling the

Clutch. The signal of the speed-indicating, expedient tachometer dynamo 19 with the electrical output signal is transmitted via the signal-receiving signal

and conditioning unit 33, which processes frequency-voltage converter 34 - in the same way as in the previously described version - the comparators of comparator unit 35 form - control signals for the various speeds of the vehicle for the logical network, in accordance with the transmission conditions resulting from the transmission chain 36, for controlling the closing range of clutch 1 at different speeds. The one on the change gear

located switches indicating the empty position 42 secures via the logical network 36 that in the

Empty position of the vehicle, with a longer standstill, in the basic position of the accelerator pedal 15 and released shift lever, the clutch 1 is closed, i.e. that the express bearing of the clutch was in no way overloaded. The position sensor 38, which detects the position of the brake pedal and is listed as a switch, can modify or accelerate the lifting of the clutch. The one on the accelerator

15 arranged, consisting of the switches 16, 17, which detects the position of the accelerator pedal, which can consist of one or more switches, on the one hand ensures the logical evaluation of the position of the accelerator pedal, or the position when the accelerator pedal is released completely, or the signal of an angular position of the accelerator pedal determined for a given type of wagon, as a result of which the lifting of the clutch can be accelerated, no unnecessary operation of the engine brake occurs during the changeover, namely because the changeover only takes place in the

Home position of the accelerator pedal 15 comes about. The

Receiving circuits 20, 27, 28, 29, 34, 41, 43 ensure the appropriate interference blanking and matching of the voltage level, or the signal conversion from the sensors to the logic network 36. The write inputs

24a, 25a, 26a of the memory circuits are controlled by the logic network 36, so are the inputs 24b, 25b, 26b of the erase circuits. The storage circuits 24, 25, 26 are expediently RS flip-flop circuits, which secure the storage of the logic signals during operation in the appropriate order and taking into account the preceding states, and indeed in such a way that different valve-controlling output values in the

Dependent on the preceding logical circumstances or the logical combination.

The control device works as follows:

Now when the driver touches the shift lever in the stationary position, at the number of revolutions of the engine of the basic run, in the closed position of the clutch and when the accelerator pedal 15 is released, the switch 14 present on the shift lever switches on and calls a logical change in the receiving circuit 27 an input of the logical network 36. At the outputs of the logical network

36 controls the mentioned signal change the write inputs 24a, 25a, 26a of the memory circuits 24, 25, 26, whereupon the outputs a control signal via the

Power amplifiers 21, 22, 23 give off the electrically operated valves 8, 9, 10, as a success they condense the space of the air container 7 with the working space of the actuating membrane 5 - which is filled with pressure medium -, causing the clutch 1 to be actuated by the shift fork

2 is raised quickly. Now the gear shift takes place, which means that the driver deactivates the switched-on position of the switch 42 indicating the idle position, steps on the accelerator pedal 15 and indicates the number of revolutions of the engine of the vehicle - the frequency increases via the conditioning unit 30 arrives at the frequency-voltage converter 31, at the output of which a signal with increasing DC voltage appears, which at one output of the comparator 32 with the one adjustable switching level causes a change in the signal level when the starting speed is exceeded.

In this way, the signal changes at the coupled input of the logic network 36. This change in the logic signal level, as well as the changes in the signals, which are caused by the switching unit 17 which detects the position of the accelerator pedal

have also caused a change in the logic signal level at the connected input of the logic via the receive circuits 28, 29

Network 36. In this way, the extinguishing input 24b of the extinguishing circuit 24 is controlled, whereupon the control of the electrically operated valve 8 ceases, as a success the working space with pressure medium of the pneumatic diaphragm 5 via the throttle 11, in the raised position of the sensor of the lifting fork 40, or in the position belonging to the high pressure of the pressure switch 6, and when the electrically operated valve 10 is in the switched-on position, it is emptied via the throttle 13. The emptying via the throttle 13, i.e. the quick closing of the clutch 1 stops when the friction surfaces are in contact, or when the sensor of the lifting fork 40 or the pressure switch 6 is switched over. Now the emptying is continued more slowly via the throttling, so that the closing force of the

Clutch 1 gradually increased and the sliding can be promoted. About a certain speed of the vehicle, about 8-10 km / h

Throttling opened with the electrically operated valve, which closes the clutch faster.

If now the number of revolutions of the engine under the set level drops, as well as the lifting of the clutch is caused in the basic position of the accelerator pedal 15. At the same time, the drop in the speed of the vehicle below the set value cannot control any of the solenoid valves per se if there are no other conditions for lifting the clutch.

In the interest of excavating the express

The bearing is in the position of the empty gear of the

Gearbox indicating switch (42) at

Basic position of the accelerator pedal 15, the clutch closed

From the mode of operation described above, it is clear that 36 different valve-controlling combinations are required for the identical input combinations of the logic network, these transition states are ensured by the storage circuits.

Claims

S AUTHORIZATION FOR AUTOMATIC OPERATION OF THE CLUTCH

FROM FARZEUG EN

P a t e n t a n s r u c h e

Control device for actuated with Druckmed i

Construction of the clutch of a vehicle, the lifting fork actuating the clutch being actuated by a member with pressure medium, in

the person communicating with the working body, the

Pressure medium conducting channel electrically operated

Valves are switched on, characterized in that the pneumatic outputs of the electrically operated valves (8, 9, 10) are connected to various throttles (11, 12, 13)

the electrical control inputs are connected to the outputs of memory circuits (24, 25) via power amplifiers (21, 22), the write inputs (24a, 25a) of the memory circuits and the erase inputs (25b, 26b) being the output of a logical network ( 36) - which is expediently a memory with a fixed program - connected, the inputs of the logical network (36) are connected to one on the

Gear lever existing switch (14), one of the

Position of the accelerator pedal (15) sensing switching unit (16, 17), as well as connected to a switch (42) indicating the neutral gear of the gearbox via receiving circuits (27, 28, 29, 43); further entrances are connected to comparators with an adjustable switching level (32, 35), the inputs of the comparators are connected to frequency-voltage converters (31, 34), the inputs of which are connected to the signal generator (14) and its output signal via signal-conditioning units (30, 33) the engine's engine speed

Displays vehicle, on the other hand, a signal generator

(33), whose electrical output signal indicates the speed of the vehicle.

2. Control device according to claim 1, characterized in that the air space - the

common output of the pneumatic valves (8,

9, 10) and the pneumatically operated diaphragm (5) - a pressure switch (6) with an adjustable switching level is connected, which is connected directly or via a receiving circuit

(26) and the power amplifier (23) an electrically operated valve (10) having a throttle (13) with a variable output is connected.

3. Control device according to claim 1, characterized in that the clutch fork actuating fork (2) a position detecting

Switch (40) is connected to an electrical output, the output of which is direct or through a

Receive circuit (41), logic network (36) and the memory circuit (26), and power amplifier (23) an electrically operated valve (10) with throttling with variable output is connected.

4. Control device according to any of the claims

1 to 3, characterized in that the

Brake pedal (37) a position sensing switch (38) is connected with an electrical output signal, the output of which is via a receiving circuit

(39) is connected to an input of the logical network (36).

5. Control device according to one of claims 1 to 4, characterized in that the signal generator (18) of the engine speed after switched comparator (32) is a controller amplifier (46) with differentiating characteristics, to emphasize the direction of change of the frequency-voltage converter ( 31) includes incoming signal.