WO1990004119A1

WO1990004119A1 - Regulating device and control unit for a continuously variable automatic transmission system

Info

Publication number: WO1990004119A1
Application number: PCT/EP1989/001150
Authority: WO
Inventors: Hansjörg DACH; Horst Reiner Butz
Original assignee: Zahnradfabrik Friedrichshafen Ag
Priority date: 1988-10-07
Filing date: 1989-09-30
Publication date: 1990-04-19
Also published as: AU4329789A

Abstract

Regulating device and control unit for an automatic transmission system with continuously variable mechanical ratio regulation. A selector lever (11) for limiting the travelling range (F_b) is arranged in a regulating device (1); when said lever is adjusted in a continuously variable manner in the area (B, 14), transmission regulation is effected in that a lower limit is set to the ratio of the transmission (Ü) and/or to the engine speed (n_m) according to the adjustment of the lever. The braking effect of the engine can thus be better adapted to the driving profile in the case of a downhill run and, in the case of a mountain road with a large number of bends, the frequency of transmission adjustment can be reduced. The driving range can be limited by hydraulic means only or, in particular, by electrohydraulic means. Notches (12) distributed over the entire adjustment area (B, 14) can be used to simplify the handling of the selector lever (11).

Description

Actuator and control for a continuously variable automatic transmission

The invention relates to an actuating device and a control for limiting the driving range of a continuously variable automatic transmission according to the preamble of claim 1.

From ATZ 89 (1987) 9 "The control of the CTX transmission" pages 455 to 465 an actuating device is known which is shown in connection with a manual valve VIII on page 463 picture 8 and described on page 464. In a similar manner to the well-known gear selector switches or selector slides, e.g. B. Figures 6 and 7 from ATZ 85 (1983) 6 page 403 with positions 1, 2 or 3, in position "L" (page 463 of the first-mentioned document) an increased engine speed is adjusted on the throttle lever during idling and for engine braking used. An advantageous adaptation of the engine braking effect to the respective driving situation is only possible in the rarest of cases using this method.

It is therefore an object of the invention to further develop an actuating device and control according to the preamble of claim 1, with which the engine braking effect can be better adapted to the particular driving situation.

This object is achieved with the characterizing features of claim 1.

While according to the prior art only a downward engine speed limit is possible in connection with a set position in the actuating device, a wide range, i.e. a large number of positions, can be set via a stepless adjustment, so that the downward engine speed limit is also reduced a relatively wide band is made possible. In this way, e.g. B. on a long downhill ride, the engine braking effect can be adapted to the respective driving profile, so that the service brake does not have to be used, or at least not often, to maintain a limited speed. In addition, the advantageous adjustment of the engine braking effect eliminates the need to continuously switch from just one braking position to the normal position for forward travel if the braking effect, measured on the slope gradient, is too strong.

It is advantageous for. B. for the activation of the engine braking effect a continuously adjustable lever, as is known from braking devices with a retarder. With a relatively large adjustment range, a lever allows good adjustment with good handling. If the known selector slide for the position of an automatic transmission for the infinitely variable adjustment effect for adapting the drive train to the driving profile is further developed, there is a particularly advantageous simplification because only one actuating lever is used for two different functions in principle. The arrangement of these two functions one behind the other as a slide or in a swivel range is advantageous for handling but also for the connection to the actuators, both with a purely hydraulic as well as with a partially or completely electronic implementation of the functions of the actuating lever, while with the stepless influencing the engine speed limit down in particular the engine braking effect can be adjusted on downhill gradients, it is possible with a gear ratio down, z. B. on a winding uphill slope, to prevent a too frequent ratio adjustment when going down from the gas at the beginning of a tight curve. The control device for the infinitely variable limitation of the engine speed or the gear ratio down can be individually, particularly advantageously, but also in combination with a pure hydraulic control, and can be conveniently connected to an electro-hydraulic control. It is particularly advantageous if the selector slide of the adjusting device for setting the driving positions is coupled in a known manner with a manual switch valve and is thus implemented purely hydraulically, while the stepless adjustment range of the selector slide for influencing - restricting - the driving range during forward travel is electro-hydraulic, e.g. B. acts with a potentiometer as an actuator in connection with the selector slide, over notches in the stepless adjustment range of the selector slide, the practical handling by the driver can be further improved.

The invention is not limited to the combination of features of the claims. For the specialist, there are further useful combinations of claims and individual claim characteristics from the task.

Further details of the invention will be explained with reference to drawings and exemplary embodiments. Show it:

Fig. 1 an actuating device in connection with

Share an electro-hydraulic control and the drive train in schematic

Presentation;

2 shows an actuating device in connection with a manual switching valve of a hydraulic control;

3 shows the division of the stroke of the selector slide / selector lever; 4 shows a representation of the stepless travel range limitation;

Fig. 5 shows an operating characteristic depending on the engine speed and

Engine torque.

1 is 4 a motor, 3 an automatic transmission and 21 the drive shaft of a vehicle 2. The automatic transmission 3 consists of a

Belt transmission 33 with the drive pulley 34 and the driven pulley 35 and from a torque converter 31 with the lock-up clutch 32 and a reversing gear 36. An electronic control unit 5 receives information about the line 42 from the throttle valve position 41,

Line 45 from the speed sensor 44 of the motor shaft 43, line 380 from the speed sensor 38, which is arranged on the drive pulley 34, and via the speed sensor 39 and line 390 from the transmission output shaft 37. To influence the electro-hydraulic control, an actuating device 1 with the Selector lever 11 is connected via line 13 to the electronic control unit 5, the selector lever 11 of the actuating device 13 being adjustable into the positions “P”, reverse gear “R”, neutral position “N”, forward travel “D” and restricted forward travel “B” . While the positions P to D are used to transmit electrical signals from fixed positions to the electronic control unit, the position B comprises an area (B_min., B_max.) In which the selector lever 11 can be continuously adjusted. A separate actuating device 10 with the selector lever 110 and the area 14 can also be arranged for controlling the restricted forward travel. To influence the electronic control unit 5, a program switch 51 with several positions is also connected via line 52. The throttle position 53 and the kick Down position 54 is fed via line 55 and brake actuation 56 via line 57 to the electronic control unit, via lines 59, 590 there are also solenoid valves 58, 580 of an electronic hydraulic control (not shown) for adjusting the transmission 3 with the electronic one Controller 5 connected, such as. B. the adjustment of the converter clutch 32 of the adjustment and contact pressure of the input and output gears 34, 35 of the belt transmission 33 and the reversing gear 36.

Fig. 2 shows again the actuating device 1 with the selector lever 11 and a manual valve 6 with the spool 61 of the hydraulic control device. The selector lever 11 is mechanically connected to the spool 61 on the fork 62, so that the spool is also adjusted analogously in the positions P, R, N and D. The line 63 of the manual control valve 6 is connected to the pressure medium source 66 and the lines 64 and 65 are connected to the clutches 360 of the reversing gear 36 for activating the forward or reverse travel. In the area 14 of the actuating device 1, in which the selector lever 11 is continuously adjustable from B_min. to B_max. can be adjusted, the manual control valve 6 is also adjusted at the same time. In the case of a stepless, purely hydraulic limitation of the forward driving range, one can

Engine brake valve 67 are acted upon via line 68 with a pressure dependent on the adjustment. Markings or notches 12 are also arranged in area 14 to facilitate the in principle stepless adjustment for the restricted forward travel. The transmission of the electrical signals from the actuating device 1 to the electronic control device 5 can preferably take place via a potentiometer 7 if the stepless travel range restriction is implemented electrically or electro-hydraulically. In Fig. 3 the stroke of the manual shift lever 11 H_ll is shown in connection with the swivel range of a potentiometer 7, the positions R, N, D being assigned fixed angles and thus electrical quantities, the range B is B_min. to B_max. in principle steplessly divided, with the markings or notches 12 leading to graded electrical quantities, which are fed to the electronic control unit 5, in a manner analogous to the positions 120, in order to facilitate adjustment.

4 is a diagram of the vehicle speed (X axis)

Motor speed n_m (Y axis) plotted. Between the lines U_max. and U_min. the transmission range of the continuously variable belt transmission is in position D for normal forward travel. According to a defined strategy, with the adjustment of the adjusting lever 11 in the area B for the restricted forward drive, either the engine speed n_m or this engine speed and also the transmission ratio u are limited downwards - n__bm, ü__b -. Everyone

Position of the selector lever 11 is assigned a predetermined engine speed and translation limitation, so that with the adjustment in the area B, 14, z. B. as shown, engine speed limits between 2,000 and 3,000 revolutions and gear ratios between 0.78 and 0.49 are possible.

With the adjustment in the area 14, B, a restriction in the forward driving area according to FIG. 5 is also possible. A characteristic curve K is plotted against the engine speed n_m (X axis) and the engine torque M_m (Y axis). Different characteristics can, as is known, via the program switch 51 for z. B. a fuel-saving automatic adjustment in the transmission (characteristic curve K) can be selected. Further characteristics for z. B. a sportier driving style up to the curve for maximum Acceleration b_max. can be called up via the program switch 51 insofar as they are stored in the electronic control unit. To influence the speed of the engine or the speed and the gear ratio of the transmission 3, it is also possible, with the adjustment of the selector lever 11 in the region B, to change a characteristic curve K which is permanently programmed in the position D, so that, analogously to an adjustment of the throttle valve _DR a higher speed is already set - Pl speed with selected characteristic with switch 51; P2 higher speed corresponding to z. B.

Setting B_max.). According to the adjustment of the selector lever 11, different speeds result for a throttle valve position _DR. The actuating and control device works as follows:

As is known, the starting of an automatic transmission takes place in the N neutral position by the selector lever 11. If driving is to be carried out forwards, the actuating lever is adjusted to D, pressure medium being conducted via lines 63 and 64 to the forward gear clutch in the reversing gear 36. With the change in the throttle lever position 53, the throttle valve 41 is also adjusted so that the vehicle starts to move forward via the drive train. The transmission 3, in particular the belt transmission 33, the torque converter 31 and the lock-up clutch 32 are automatically adjusted in accordance with the characteristic curve selected via the program switch 51 by the electronic control unit 5 and the electro-hydraulic control. The throttle valve 41 can be adjusted directly via a coupling to the throttle lever adjustment 53, but also via the electronic control unit 5 - E-gas -. In position D, the entire driving range between the idling speed and the maximum speed and the maximum gear ratio and minimum gear ratio is selected by the automatic system in accordance with that selected using the program switch

Characteristic curves K used, on the position of the selector lever 11 in Area B, 14 of the actuating device 1, the braking behavior when driving downhill and the driving performance during acceleration and when driving uphill can be positively influenced, with the stepless adjustment of the selector lever 11 influencing the transmission control in such a way that the engine speed is continuously limited downwards according to the lever position ( Fig. 4). Via the same actuation of the selector lever 11, the transmission control can be influenced in such a way that the transmission ratio is infinitely limited in accordance with the lever position downwards - in the direction of overdrive. According to a further strategy, the transmission control can be influenced so that the normal control line - characteristic curve K -, z. B. the engine speed as a function of the throttle valve position is changed so that the engine speed is increased in more or less large areas, the amount of the excess of the respective driving conditions, for. B. the engine speed, the output speed, the speed gradient, the accelerator pedal position or the brake pedal position 56, depends. The continuously actuable lever can be separately in the driver's area in an actuator 10, z. B. as a brake lever 110 in connection with a hydrodynamic brake, or as described, as a selector lever 11 of a known actuating device 1 of an automatic transmission 3. To simplify the setting of the selector lever in the continuously variable range B_min. , B_max., 14 detents 12 or markings can be arranged, which are distributed over the entire area or are only partially arranged. As described, the infinitely variable travel range limitation can be implemented electro-hydraulically, but also purely electrically (electronically) as well as purely hydraulically. Reference numerals

57 line

58, 580 solenoid valves

59, 590 line

6 manual switching valve 61 spool

62 fork

63 line

64 line

65 Line 66 pressure medium source

67 Engine brake valve

68 line

7 potentiometers

P parking position

R reverse gear position

N neutral position

D forward driving position

B Forward driving position restricted area

B_min. minimal restriction

B_max. maximum restriction

H_ll stroke from selector lever

U gear ratio U_max. maximum gear ratio ü_min. minimum gear ratio n_m engine speed v vehicle speed

F_b travel range limitation n__bm engine speed limitation ü_b transmission limitation

M_m engine torque

K normal control curve / operating characteristic / normal control line b_max. Characteristic curve for the maximum acceleration

DR Throttle valve adjustment angle Pl engine speed on the normal control curve at x_DR P2 increased engine speed after maximum adjustment in area B at x_DR V full load curve

Claims

Expectations

1. Setting device and control for an automatic transmission (3) designed for a motor vehicle (2) with a continuously variable mechanical transmission control, in which the transmission transmission as a function of the

Engine speed (n_m) and the driver's power requirement (throttle lever position 53) is carried out with an adjusting device (1) for the positions of the parking position (P), neutral position (N), reverse travel position (R) and automatic adjustment during forward travel (D) and with another shot during the

Forward driving, in which the normal automatic control is restricted, is achieved by setting the driver for the restricted forward driving via an infinitely variable adjusting device (1, 10).

2. Actuating device according to claim 1, characterized in that a lever (11, 110) is arranged which is infinitely adjustable in a region (B, 14).

3. Adjusting device according to claim 2, characterized in that a selector slide (11) in an adjusting device (1) for adjusting the positions (P, R, N, D) for the automatic transmission (3) as an actuating lever and for the continuously effective restriction of automatic control during forward travel is arranged in a second function as a selector lever (range B_max., B__min.).

4. Actuating device according to claim 3, characterized in that the area with the positions (P, R, N, D) and the stepless area for influencing the automatic control (B, 14) in the actuating device (1) in a common pivoting range of the selector slide (11) are arranged one behind the other.

5. Actuating device according to claim 4, characterized in that the automatic transmission control is influenced via the continuously actuable selector lever (11) in the area (B, 14) in such a way that the engine speed (n__m) is limited downwards (n_bm).

6. Actuating device according to claim 4, characterized in that the influencing of the automatic transmission control via the continuously actuable selector lever (11) in the area (B, 14) is such that the transmission ratio (U) is continuously, corresponding to the lever position, down - in Direction overdrive - is limited (U_b).

7. Actuating device according to claim 4, characterized in that the influencing of the automatic transmission control via the continuously actuated selector lever (11) in the area (B, 14) is such that the engine speed (n_m) and the gear ratio (ü) according to the lever position is limited below (n_bm, U__b).

8. Setting device according to claim 4, characterized in that the influencing of. Automatic transmission control via the continuously actuable selector lever (11) in area (B) is carried out in such a way that the operating characteristic (normal control curve K) is changed in such a way that the engine speed (nm) is increased in more or less large areas (A_l, A_2).

9. Actuating device according to claim 7, characterized in that the measure of the engine speed increase from the respective driving conditions, such as the engine speed (n_m), the output speed (n-ab), the speed gradient, the accelerator pedal position (53) or the brake pedal position (56), depends.

10. Actuating device according to claim 7, characterized in that the automatic transmission control is influenced purely hydraulically.

11. Actuating device according to claim 10, characterized in that the selector slide (11) is connected to a manual control valve (6) of a hydraulic control, via the pressure medium according to the set positions (P, R, N, D) to different valves and couplings ( 360) is conducted and via which a pressure dependent on this adjustment is fed to an engine brake valve (67) in the area of the infinitely variable adjustment (B), which regulates a higher speed without the accelerator pedal (53) having to be operated.

12. Actuating device according to claim 7, characterized in that the automatic transmission control is influenced electrically (electronically) via the steplessly actuated selector lever (11) in the region (B).

13. Actuating device according to claim 12, characterized in that the selector slide (11) is connected to a manual switching valve (6) of an electro-hydraulic control via which the pressure medium according to the set position (P, R, N, D) to different valves and couplings (360) and that for these positions and for the range of stepless

Adjustment (B) a potentiometer (7) is arranged and that the electrical signals proportional to the lever adjustment are sent to the hydraulic control device via an electronic control unit (5) and via solenoid valves (58, 580).

14. Actuating device according to claim 4, characterized in that detents or markings (12) are arranged over the entire adjustment range (B_min., B_max.) In the area for the stepless adjustment (B) of the selector lever (11).

15. Actuating device according to claim 4, characterized in that the area (B) for the stepless adjustment by the selector lever (11) is arranged only in certain positions which are striking for the operation.