JPS63167155A - Control device for electronic control transmission - Google Patents

Abstract

PURPOSE:To avoid a sudden shift, by furnishing a control device to give an oil damper function by the throttling effect of an operation fluid to a shift actuator at the time when the synchronization of the transmission is completed. CONSTITUTION:Signals of the shift position of a shifting shaft 1e and the selected position of a selection shaft 4e are input to an electronic control unit 2 to detect the shifted gear stage. When the completion of the synchronization of the transmission is confirmed, an electromagnetic valve V5 of an actuator 1B is turned on, and the oil damper effect is given to the cylinder by the throttling action of the valve V5. Therefore, a sudden operation of the piston after the sychronization can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a shift control device for an electronically controlled automatic transmission that controls shift by driving an actuator using fluid pressure.

(Prior Art) In recent years, automatic transmissions that control vehicle transmissions using electronic control devices have been developed.

In such electronically controlled automatic transmissions, the solenoid valves that supply fluid pressure to the actuators are selectively controlled to open and close in response to commands from the electronic control unit that receives signals such as vehicle speed and the amount of accelerator pedal depression. The select actuator is operated to perform a shift operation or a gear select operation.

FIG. 6 is a schematic configuration diagram of an example in which a double piston type shift actuator is used and hydraulic pressure is used as the fluid pressure. In this case, the shift actuator 1 consists of a cylinder part 1a and a piston part 1b, and the piston part 1b has a piston rod 1b1 having a diameter φA, a piston rod 1b1 having a diameter φA, and a piston rod 1b1 having a diameter φA.
Enlarged part 1b2 with B, 2 with outer diameter φD and inner diameter φB
It has two ring portions 1b4. Therefore, in this case, each thrust is as follows.

F1'(F2'): Force acting on the enlarged portion 1b2 when the TIFa valve Vl (valve V2) is opened F5'(F4'): When the solenoid valve V2 (or solenoid valve Vz) is opened The force acting on the ring portion lb4, where P is the hydraulic pressure.

Under these conditions, it is necessary to satisfy the following first-order condition. In other words, (1) Fl'(F2') must not exceed the allowable shift force of the shift actuator and must work within the allowable shift time; (2) F3'(F4'') must be the thrust force required for gear extraction. , etc.

This shift actuator l operates as follows.

First, when only the solenoid valve v1 is turned on and opened, hydraulic pressure acts on the right side of the enlarged portion tb2, and the piston rod tb is pushed and moved to the left side by the force of Fl', and takes an R biased position. Further, when only the solenoid valve v2 is turned on, the hydraulic pressure pushes and moves the protruding portion 1b of the piston rod to the right side with the force F2', so that it assumes the L-biased position.

Also, if the solenoid valves V 1 + v 2 are turned on at the same time,
Forces F5', F,' act on the two rings lb4 from the left and right, causing the enlarged portion 1b2 sandwiched between the rings lb4 to be in the neutral position.

(Problem to be solved by the invention) By the way, in electronically controlled automatic transmissions, gear shift control involves sending hydraulic or air pressure to cylinders by simply turning on and off a solenoid valve when a gear is engaged or disengaged. However, when a pneumatic cylinder is used, air is a compressible fluid and has a spring action, and a large amount of air is fed through a minute gap, which can damage the synchronizer mechanism. For example, if you shift up a gear,
Or, when downshifting, the synchronization time will be longer due to the large rotational difference before and after the gearshift, but at synchronization the thrust will reach maximum and the piston will stop, so simple on/off control of the solenoid valve will not allow air to be injected into the cylinder. , the cylinder pressure changes to supply pressure. For this reason, after synchronization, the piston shifts at high speed due to the air pressure stored in the cylinder, due to the air spring action and air injection. At this time, on the gear side, the sleeve collides with the dog teeth of the gear at high speed, sometimes causing damage to the dog teeth.

In order to prevent such damage to the synchronizer mechanism, the cylinder thrust is kept small to cover the durability of the transmission, but the small thrust increases the downshift time and makes it difficult to shift in cold weather or on downhill roads. The time becomes longer, and the clutch disengagement situation continues for a long time.
There is a problem in that safety during vehicle operation is impaired.

In order to prevent damage to the synchronizer mechanism as described above, a transmission control device proposed in, for example, Japanese Patent Application Laid-Open No. 60-84448 is known, but it is known to reduce shift time while maintaining the durability of the transmission. It was not possible to sufficiently respond to the request to shorten the length and improve vehicle performance.

Therefore, the present invention aims to solve the problems of the prior art. The present invention provides a speed change control device for an electronically controlled automatic transmission.

(Means for Solving the Problems) The shift control device for an electronically controlled automatic transmission of the present invention applies an oil damper action to the shift actuator by the throttling effect of one working fluid when synchronization completion of the transmission is detected. The present invention is characterized in that it is provided with a control means for controlling.

(Function) In the present invention, when the completion of synchronization is detected in the shift operation of the transmission, the shift actuator is provided with a control means that applies an oil damper action by the throttling effect of the working fluid. However, damage to the dog teeth of the synchronizer mechanism can be prevented, ensuring both the durability of the transmission and the driving performance of the vehicle.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a shift control device for an electronically controlled automatic transmission according to the present invention.

In the figure, IA is a shift actuator that performs a shift operation of the transmission, and is configured to be able to stop at three positions, and is similar to that explained in FIG. 6. A shift shaft 1e of the transmission is attached to the piston rod end 1b+ of the piston 1b, and the piston moves downward in response to the magnitude of the fluid pressure acting on the cylinder la, thereby changing gears from 1 to 3. -5th gear side, neutral N t
, N2+N3 side, R-2-4 speed side.

Numerals v, , and v2 are three-port electromagnetic valves that control the supply of working fluid from the pump 3 as a fluid pressure source to the respective fluid chambers, and this is done in response to commands from the electronic control unit M2.

Reference numeral 4 denotes a select actuator that performs a selection operation of the transmission, and can be stopped at three positions similarly to the shift actuator 1 described above. This is a stepped cylinder 4a,
The stepped cylinder 4a is composed of a first piston 4b, a cylindrical second piston 4C, a piston rod 4d, and a select shaft 4e, and has fluid chambers 4f and 4g at both ends thereof.

When fluid pressure acts on both fluid chambers 4f and 4g without any difference in response, the piston rod 4d becomes in a neutral state, and the fluid chamber 4
When fluid pressure acts only on f, the select shaft 4e is driven in the N3 direction, and when fluid pressure acts only on the fluid chamber 4g, the select shaft 4e is driven in the N1 direction.

ViS and V4 are three-boat solenoid valves that supply working fluid from a pump ticket to fluid chambers 4f and 4g according to commands from electronic control device 2 to control operation of select actuator 4.

5 is a stroke sensor that detects the shift position of the shift shaft 1e, 6 is a position switch that detects the select position of the select shaft 4e, and the detected signals are input to the electronic control equipment building, and the combination of these signals , the shifted gear is detected.

The electronic control device 2 is composed of a microcomputer,
It has a central processing unit, various memories, and input/output devices. And stroke sensor 5, position switch 6
In addition to signals transmitted from Signals are input, and the various electromagnetic valves v1 to We, a clutch actuator (not shown), etc. are controlled based on these detection signals.

1B is the other 7 that is directly connected to the shift actuator IA.
The shift actuator IA has the same structure as the shift actuator IA. This actuator IB has 2
Working fluid is supplied by a solenoid valve v5 that acts as a throttle valve for the boat, and the working fluid is fed from a tank 8 through a check valve 7.

As will be described later, when it is confirmed that the synchronized operation of the transmission has finished, the solenoid valve V5 is turned on, and its throttling action applies an oil damper effect to the cylinder.
To prevent sudden movement of the piston after synchronization and avoid damage to dog teeth. In addition to being arranged in series with the shift actuator IA, the actuator IB may be arranged in parallel with the actuator LA and connected using a suitable transmission mechanism.

Next, FIG. 2(a) is a block diagram showing a second embodiment of the present invention, in which a damper piston ld having an oil ring IC is further provided in the double piston shown in FIG. 6 as a shift actuator. It uses a three-ton piston structure. In this example, similar to the first example,
After confirming that synchronization is complete, check valve 7 from tank 8.
The fluid sent through the damper piston 1d is supplied to the damper piston 1d by a solenoid valve v5 which acts as a two-boat throttle valve.

The solenoid valve v5 is operated until the dog teeth are completely inserted (until time t3 in FIG. 4(a)), that is, until the stroke is completed.

FIG. 2(b) shows a third embodiment of the present invention, in which the shift actuator 1 includes a double piston,
A damper piston with a smaller cylinder (2) volume than the one in FIG. 2(a) is installed, and the amount of working fluid is reduced.

Further, as shown in FIG. 3, an input shaft sensor (TMN) for detecting the rotation speed of the transmission top gear and a vehicle speed sensor are attached to the transmission.

Next, the characteristics of the transmission are shown in FIG. 4(a).

This will be explained with reference to the characteristic diagram (b).

FIG. 4(a) shows the characteristics when the vertical axis represents the detected value by the transmission shift stroke sensor 5, that is, the gear stroke, and the horizontal axis represents time.
The dog teeth are inserted between 2 and t3.

In Fig. 4(b), the input shaft sensor (T
MN), and the horizontal axis is the time axis, and the synchronizing operation starts at time 11 and ends at time t2.

The specific operation of the present invention will be explained below with reference to the control flow diagram of FIG.

At the start of a transmission shift, a shift command to a predetermined gear is read in step Pl, clutch gear control is performed in step P2, and shift-side solenoid valve V1. V2 is controlled to open and the gear is pulled out, and then in step P4 the select side solenoid valve v3 or v
4 open control is performed to hold the shift and select actuator at that gear position.

In step P5, the shift solenoid valves v1 and v2 are controlled to close, and the shift actuator is operated. Next, on the 772nd day of ST.
Based on the value of N), (dTMN/dT=0) is calculated and checked to see if the synchronization operation is completed. If the judgment is NO, the process returns to step P5, and the judgment is YE.
If S, then in step P7, it is determined whether the value of TMN in L is TMN=vXGXK, where V is the vehicle speed, G is the gear ratio of the gear to be changed, and K is the coefficient. , it is checked whether the vehicle speed and the rotational speed of the input shaft match, and if the determination is NO, the process returns to step P5 and below, and if the determination is YES, the process proceeds to Step 772. The processing of P7 is
This is to determine whether it is a synchronization start point or a synchronization completion point.

In step 772, if the first judgment is YES, the process proceeds to the next processing step PIO, and if the judgment is NO, the solenoid valve v
5 is closed, the 2-port throttle valve is operated, and an oil damper effect is applied to shift using only the air pressure stored in the cylinder to prevent sudden shifting.

In step P9, the stroke sensor 5 checks whether the shift has been completed. If the shift has not been completed, step PIG checks whether the shift is before or after the shift time αsec, which is a level that does not cause any problem in running the vehicle, has elapsed. However, if it has not passed, the process returns to step P9, and if it has passed, the solenoid valve v5 is controlled to open at step pH,
Execute a forced shift. If it is before α seconds have elapsed, the solenoid valve v
5 is not released.

If shift completion is confirmed in step P9.

Next, in step P12, the clutch is engaged, and then in step ptg, the shift side solenoid valve Vl or v2 is closed.
In step P14, the select side solenoid valve v3 or v4 is closed. Finally, in step P1!5, the solenoid valve v5 is opened to return to the original state, thereby preventing the damper from acting in the example of FIG. 2(a).

Although one embodiment of the present invention has been described below, various modifications can be made within the scope of the present invention, and these are not excluded from the scope of the present invention.

(Effects of the Invention) As explained above, according to the present invention, a control means is provided for applying an oil damping effect to the shift actuator by throttling the working fluid when synchronization completion of the transmission is detected. , sudden shifts can be avoided, and even if the thrust force is increased during shifting, damage to the dog teeth can be prevented.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the configuration of the present invention, Figures 2 and 3 are explanatory diagrams, Figures 4 (&) to (b) are characteristic diagrams, Figure 5 is a flowchart, and Figure 6 is an outline of the shift actuator. FIG. 1... Shift actuator, 2... Electronic control device, 3... Pump, 4... Select actuator,
5... Stroke sensor, 6... Position switch, 7... Check valve. Patent applicant: IsuC Automobile Co., Ltd. Representative: Patent attorney Minoru Tsuji No. 1
Figure 3 Figure 4 (2) Figure 5

Claims (1)

[Claims] When transmission synchronization completion is detected,
1. A shift control device for an electronically controlled automatic transmission, characterized in that a shift actuator is provided with a control means for applying an oil damper effect by a throttling effect of working fluid.