JPH06213315A - Selection shock reducing device of automatic transmission for car - Google Patents

Abstract

PURPOSE:To reduce the shift shock when the gearing position is selected to the running range by decreasing the line pressure to a certain amount lower when the car is at a standstill in the condition that an idle-up means is in function and that the degree of throttle opening is over the set value. CONSTITUTION:Solenoid valves SOL1-SOL3 are On/Off controlled by an ECU, and thereby a 1-2 shift valve, 2-3 shift valve, and primary regulator valve as line pressure decreasing means are switched to generate a plurality of shift positions. The ECU is fed with output signals from a car speed sensor 41, shift switch 43, and throttle sensor 45, and if a shift lever is selected from the P or N range into the running range, the elapsed time thereafter is clocked. If the clocked time lies within the set period of time, the solenoid valve SOL3 is operated on the condition that the car is at a standstill and the degree of throttle opening is over the set value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a select shock reducing device for a vehicle automatic transmission.

[0002]

2. Description of the Related Art As one type of conventional automatic transmission for a vehicle, a throttle sensor for detecting a throttle opening and a solenoid valve is operated when the throttle opening is less than a set value so that the line pressure is a predetermined amount from the set value. Some vehicles are equipped with a line pressure reducing means for reducing the pressure to a low level, and an engine control device equipped with an idle up means for changing the throttle opening to a set value or more.

[0003]

By the way, in the above-mentioned conventional apparatus, when the idle-up means functions and the throttle opening becomes equal to or more than the set value, the line pressure reducing means does not function and the line pressure becomes the set value. To be done. Therefore, when the shift lever is selected from the P or N range to the traveling range in a vehicle stopped in such a state, a large shift shock occurs because the line pressure is the set value. The present invention has been made to address the above-mentioned problems, and an object thereof is to reduce the above-mentioned shift shock.

[0004]

In order to achieve the above-mentioned object, in the present invention, a throttle sensor for detecting a throttle opening, and a solenoid valve is operated to operate the line pressure when the throttle opening is less than a set value. In a vehicle automatic transmission equipped in a vehicle, which is provided with a line pressure reducing means for making a predetermined lower pressure than a set value, the engine control device has an idle up means for changing the throttle opening to a set value or more, The time measuring means for measuring the elapsed time after being selected from the P or N range to the travel range, the stop detecting means for detecting that the vehicle is stopped, and the elapsed time measured by the time measuring means within the set time. If so, valve operating means for operating the solenoid valve on condition that the vehicle is stopped and the throttle opening is equal to or greater than a set value. Provided.

[0005]

In the select shock reducing device for an automatic transmission for a vehicle according to the present invention, the vehicle is stopped while the idle-up means is functioning (the throttle opening is equal to or more than the set value). When the shift lever is selected from the P or N range to the traveling range in the vehicle, the elapsed time after being selected from the P or N range to the traveling range is measured by the time measuring means, and the vehicle stop is detected by the stop detection means. The valve actuating means actuates the solenoid valve for a set time to reduce the line pressure to a predetermined amount lower than the set value for the set time. Therefore, in this case, even though the idle-up means is functioning and the throttle opening is equal to or larger than the set value, the automatic transmission is shifted by the line pressure which is lower than the set value by a predetermined amount. As a result, shift shock is reduced.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a known three-speed automatic transmission for an automobile, the gear train of which includes a torque converter T, planetary gear mechanisms G1 and G2, and hydraulic clutches C1 and C2 for shifting and hydraulic brakes B1 and B2. And a one-way clutch F1 and the like, and a hydraulic clutch C
1, C2 and operation of each element such as hydraulic brakes B1, B2
The non-actuation is configured to be controlled by the hydraulic control device.

The hydraulic control system includes a manual valve 13 that operates in response to a select operation of the shift lever 11, a primary regulator valve 15, a pressure relief valve 17, and pressure modifier valves 19 and 1.
-2 shift valve 21,2-3 shift valve 23, low cost modulator valve 25, oil cooler bypass valve 27, and pump 29 driven by the engine
The oil cooler 31 and the accumulators 33 and 35 are provided, and the electronic control unit ECU shown in FIG. 2 turns on the operation according to the select operation position (shift position) of the shift lever 11, the vehicle speed, and the throttle opening.
OFF-controlled solenoid valves SOL1, SOL
2 and SOL3, and the above-mentioned components are the hydraulic clutches C1 and C2 and the hydraulic brakes B1 and B described above.
2 etc. are connected as shown. The pump 29
The engine that drives the engine is controlled by an engine control device (not shown) having a known idle-up means. For example, at low temperature start, the throttle opening (θ) is a predetermined value θ1% (θ1 ≧ θo ) Is supposed to be.

As shown in FIG. 2, the electronic control unit ECU includes the solenoid valves SOL1, SOL2 and SOL.
Vehicle speed sensor 4 that is connected to the vehicle 3 and detects the vehicle speed
1 and the shift switch 43 for detecting the select operation position of the shift lever 11 and the throttle sensor 45 for detecting the throttle opening, and are composed of a microcomputer and a solenoid drive circuit. The microcomputer includes a CPU, ROM, RAM, I / O,
A timer or the like is configured to execute a program stored in the ROM and corresponding to the flowcharts of FIGS. 3 and 4 until the ignition switch IG of the vehicle is turned on and off.

Next, the operation of this embodiment constructed as described above will be described with reference to the flow charts of FIGS. 3 and 4. When the ignition switch IG is turned on, the microcomputer starts executing the program in step 100 of FIG. 3, initialization necessary for executing the program is performed in step 101, and the mode control routine is executed in step 102. The line pressure control routine is executed in step 103, and it is determined in step 104 whether the ignition switch IG is ON or not.
If “O” is determined, the process proceeds to step 105 to end the execution of the program, and if “YES” is determined, step 1 is performed.
Returning to 02, the above-described processing of steps 102 and 103 is repeatedly executed. The mode control routine of step 102 is publicly known, and by executing this mode control routine, the solenoid valves SOL1, SOL2, SOL3 are selected according to the select operation position (shift position) of the shift lever 11, the vehicle speed and the throttle opening. The operation of is controlled to be ON / OFF, and each mode is selected at each shift position as shown in FIG.

By the way, in the line pressure control routine of step 103, the program shown in the flowchart of FIG. 4 is executed, the vehicle speed (V) is read in step 111, and the throttle opening (θ) is read in step 112.
Is read, and the shift switch signals (P, R, N, D, 2, L) are read in step 113, and step 1
At 14, the select operation position of the shift lever 11 is PorN.
It is determined whether or not it is in the range, and if “NO” is determined, the procedure proceeds to step 115, and if “YES” is determined, the procedure proceeds to step 116 where the value t of the P / N release timer is cleared to zero. Go to step 118.

In step 115, it is judged whether or not the previous PorN range was set depending on whether the value t of the P, N release timer is zero, and if "NO" is judged, step 118 is executed.
Jump to and if “YES” is determined, step 11
After proceeding to step 7 to start the P and N release timer, the procedure proceeds to step 118. In step 118, it is determined whether or not the solenoid valve SOL3 is currently ON and is open, and if "NO" is determined, steps 121 to 125 are performed.
Is executed, and if “YES” is determined, steps 131 to
Execute 135.

In step 121, it is determined whether or not the value t of the P, N release timer is not zero and is equal to or less than the set time To (1 to 2 seconds). If "NO" is determined, the process proceeds to step 122 and "YES". If it is determined to be “”, the process proceeds to step 123.
In step 122, it is determined whether the throttle opening (θ) is less than θo%, and if “NO” is determined, step 1
The routine proceeds to 40 and returns, and if "YES" is determined, the routine proceeds to step 125. In step 123, it is determined whether or not the vehicle speed (V) is zero, and if “NO” is determined, the procedure proceeds to step 140 to return, and if “YES” is determined, the procedure proceeds to step 124. In step 124, it is judged whether or not the throttle opening (θ) is equal to or less than a predetermined value θ1% obtained by the functioning of the idle-up means.
If “O” is determined, the process proceeds to step 140 and returns, and if “YES” is determined, the process proceeds to step 125.
In step 125, the ON signal is output to the solenoid valve SOL3. As a result, the solenoid valve SOL3 of FIG. 1 is opened and the line pressure controlled by the primary regulator valve 15 is reduced by a predetermined amount from the set value.

On the other hand, in step 131, it is judged whether or not the value t of the P, N release timer is not zero and is less than or equal to the set time To, and if "NO" is judged, the routine proceeds to step 132,
If “YES” is determined, the process proceeds to step 133. In step 132, it is determined whether the throttle opening (θ) is θo% or more, and if “NO” is determined, step 140
And returns, and if "YES" is determined, the operation proceeds to step 135. In step 133, it is determined whether or not the vehicle speed (V) is zero, and if "NO" is determined, step 1
35, and if “YES” is determined, step 134
Proceed to. In step 134, it is determined whether or not the throttle opening (θ) exceeds a predetermined value θ1%, and if “NO” is determined, the process proceeds to step 140 to return and “Y
If "ES" is determined, the process proceeds to step 135. In step 135, the OFF signal is output to the solenoid valve SOL3. As a result, the solenoid valve SOL of FIG.
3 is closed and the line pressure controlled by the primary regulator valve 15 is set to a set value.

Therefore, for example, when the vehicle is stopped, the select operation position of the shift lever 11 is in the PorN range, and the idle-up means functions in the engine to set the throttle opening to the predetermined value θ1% (θ1 ≧ θo). If there is, then each step 111, 112, 1 in FIG.
13, 114, 116, 118, 121, 122, 14
0 is repeatedly executed. By the way, when the shift lever 11 is selected to the traveling range (for example, DorR range) in such a state, each step 111, 112, 113, 114, 115, 117, 1 of FIG.
18, 121, 123, 124, 125, 140 are executed, and steps 111, 112, 11 are executed after the second time.
3,114,115,118,131,133,13
4, 140 are repeatedly executed. Thus, when the value t of the P, N release timer exceeds the set time To, step 1
It is determined to be “NO” at 31 and “Y” at step 132.
Since “ES” is determined, step 135 is executed. Therefore, thereafter, as long as the idle-up means is functioning, the steps 111, 112, 113, and
114, 115, 118, 121, 122, 140 are repeatedly executed.

As a result, in the vehicle stopped with the idle-up means functioning, the shift lever 11
Is selected from the P or N range to the travel range, the elapsed time t after the selection from the P or N range to the travel range is measured by the P and N release timers, and the vehicle stop is determined in steps 123 and 133. Then, the solenoid valve SOL3 is operated for the set time To, and the line pressure is made lower than the set value by a predetermined amount for the set time To. Therefore, in this case, even though the idle-up means is functioning and the throttle opening is set to the predetermined value θ1, the shift of the automatic transmission is performed by the line pressure which is lower than the set value by the predetermined amount. As a result, shift shock is reduced.

If the shift lever 11 is in the P or N range in a vehicle stopped with the idle-up means not functioning, the steps 111, 112, 113, 114 and 116 of FIG. , 118,
121, 122, 125, 140 are executed, and each step 111, 112, 113, 1 in FIG.
14, 116, 118, 131, 132, 140 are repeatedly executed, so the shift lever 11
Is selected from the P or N range to the travel range, it is determined to be "NO" in step 114 and the steps 115, 117, 118 and 13 of FIG.
1, 133, 134, 140 are executed, and after the second time, steps 111, 112, 113, 114, 115, 11 are executed until the value t of the P, N release timer exceeds the set time To.
8, 131, 133, 134 and 140 are repeatedly executed. Therefore, in this case as well, the shift in the automatic transmission is performed by the line pressure which is lower than the set value by a predetermined amount, and the shift shock is reduced. If the accelerator is operated and the throttle opening exceeds the predetermined value θ1% by the time the value t of the P / N release timer reaches the set time To, it is determined to be "YES" in step 134 and the solenoid valve S
OL3 is turned off and the line pressure is set to the set value. Further, when the accelerator is operated and the throttle opening becomes θo% or more after the value t of the P / N release timer exceeds the set time To, it is determined to be “YES” in step 132 and the solenoid valve SOL3 is turned off. The line pressure is a set value.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a three-speed automatic transmission for a vehicle.

FIG. 2 is a block diagram of a control device that controls the operation of each solenoid valve shown in FIG.

3 is a flowchart showing an example of a program executed by a microcomputer in the electronic control device of FIG.

FIG. 4 is a flowchart showing an example of the line pressure control routine of FIG.

5 is a diagram showing a relationship between actuation / non-actuation (connection / disconnection) in each mode of the hydraulic clutch and the hydraulic brake shown in FIG.

[Explanation of symbols]

11 ... Shift lever, 15 ... Primary regulator valve (line pressure reducing means), 41 ... Vehicle speed sensor, 43 ...
Shift switch, 45 ... Throttle sensor, SOL3 ...
Solenoid valve, ECU ... Electronic control unit.

Claims (1)

[Claims] 1. An engine comprising: a throttle sensor for detecting a throttle opening; and a line pressure reducing means for activating a solenoid valve when the throttle opening is less than a set value to reduce the line pressure by a predetermined amount below the set value. In an automatic transmission for a vehicle equipped with a vehicle in which a control device changes an opening degree of a throttle to a set value or more, the elapsed time after being selected from a P or N range to a travel range is measured. If the time measuring means, the vehicle stop detecting means for detecting that the vehicle is stopped, and the elapsed time measured by the time measuring means within the set time, the vehicle is stopped and the throttle opening is equal to or more than the set value. As a condition, valve shock actuating means for actuating the solenoid valve is provided, and a selective shock reducing device for an automatic transmission for a vehicle is provided. Place