JP2002340055A - Synchromesh automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in gear shifting during the change of a clutch excitation current value wherein a difference between a clutch excitation current value in starting up-shifting and a clutch excitation current value in starting clutch OFF is generated to cause a difference between clutch OFF time predicted from a map and real clutch OFF time and reduction effect for abrupt deceleration cannot be fully obtained. SOLUTION: In this synchromesh automatic transmission 3, an electromagnetic clutch 2 to transmit or disconnect power from an output shaft of an engine 1 to an input shaft, and a control unit 4 to control the electromagnetic clutch by a constant clutch excitation current between start of up-shifting and start of clutch disconnection are provided. The abrupt deceleration at the time of clutch disconnection can thus be reduced even when gear shift is started during the change of the clutch excitation current value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to clutch control of a synchronous automatic transmission, and more particularly to a rapid change in deceleration when the clutch is turned off even when a shift is started while the clutch exciting current value is changing. The present invention relates to a synchromesh type automatic transmission which reduces the transmission.

[0002]

2. Description of the Related Art As a control method of a synchronous mesh automatic transmission, there is one disclosed in Japanese Patent Application Laid-Open No. 60-35633. In this case, the clutch OFF speed and the throttle closing speed at the start of the shift are changed using the accelerator pedal depression amount as a parameter.

However, if the accelerator pedal is operated while the throttle is being controlled to the closed side after the start of the shift, the relationship between the clutch closed position and the throttle closed position in the conventional method using the accelerator pedal depression amount as a parameter is considered. Unfortunately, there are problems such as occurrence of deceleration and engine blow-up.

[0004] As a method of controlling a synchromesh automatic transmission to solve this problem, Japanese Patent Application No. 12-17506 discloses a method.
As shown in No. 6. That is, the throttle closing speed is determined from the map based on the accelerator pedal depression amount at the start of the upshift. Next, the time required for the throttle to be fully closed is predicted from the throttle closing speed and the throttle opening at the start of the upshift, and the time required for clutch OFF is predicted from a map of the clutch excitation current value and the engine speed. By determining the OFF start time, a sudden change in the deceleration when the clutch is turned off is reduced.

[0005]

Problems to be Solved by the Invention Japanese Patent Application No. 12-1750
In the case of the device shown in No. 66, when the clutch exciting current before and after the start of the shift has not changed, the expected clutch O
A sharp deceleration change reduction effect at the time of FF can be obtained. However, actually, the clutch exciting current value changes depending on the operating state at that time, and the shift may start while the clutch exciting current value is changing. In such a case,
Clutch excitation current value and clutch O at the start of upshift
A difference occurs between the clutch excitation current value at the start of the FF and the clutch OFF time predicted from the map and the actual clutch OF.
There is a difference in the F time. For this reason, there has been a problem that the effect of reducing the sudden deceleration change when the clutch is off cannot be sufficiently obtained.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem. Even when a shift is started while the clutch exciting current value is changing, a sudden change in the deceleration when the clutch is OFF is prevented. It is an object of the present invention to obtain a synchromesh type automatic transmission which can reduce the number of transmissions.

[0007]

SUMMARY OF THE INVENTION A synchronous mesh automatic transmission according to the present invention includes: an electromagnetic clutch for transmitting or interrupting power from an output shaft of an engine to an input shaft of the synchronous mesh transmission; And control means for controlling the electromagnetic clutch with a constant clutch exciting current from the time until the start of clutch OFF.

[0008] The synchronous meshing automatic transmission according to the present invention includes an accelerator position sensor for detecting an amount of depression of an accelerator pedal, and a throttle position sensor for obtaining a throttle opening of a throttle valve provided in an intake pipe of the engine. And a crankshaft rotation sensor for detecting a rotation speed of the engine, wherein the control means controls the electromagnetic clutch based on signals from the accelerator position sensor, the throttle position sensor, and the crankshaft rotation sensor. Is controlled to be constant from the start of the upshift to the start of the clutch OFF.

Further, in the synchronous automatic transmission according to the present invention, the control means obtains a time until the throttle is fully closed based on signals from the accelerator position sensor and the throttle position sensor, and the crank means. The clutch OFF time is obtained based on a signal from the shaft rotation sensor, and the clutch exciting current is constant from the start of the upshift to the start of the clutch OFF based on the relationship between the time until the throttle is fully closed and the clutch OFF time. Is controlled as follows.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A synchronous meshing automatic transmission according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 shows Embodiment 1 of the present invention.
FIG. 1 is a diagram showing a configuration of a synchronous automatic transmission according to the first embodiment.
In the drawings, the same reference numerals indicate the same or corresponding parts.

In FIG. 1, 1 is an engine, 2 is an electromagnetic clutch, 3 is a synchronous mesh transmission, and 4 is a control unit (control means).

In FIG. 1, 5 is a shift / select actuator, 6 is a shift / select position sensor, 7 is an accelerator position sensor, 8 is a shift lever, 9 is a transmission output shaft rotation sensor, 10 is a throttle actuator, 11 Is an intake pipe, 12 is a throttle valve, 13 is a crankshaft rotation sensor, 14 is a throttle position sensor, 21 is a crankshaft of the engine 1, 22
Is an input shaft of the synchronous meshing transmission 3 and 23 is an output shaft of the synchronous meshing transmission 3.

As shown in FIG. 1, an intake pipe 1 of an engine 1
1, a throttle valve 12 is provided. The throttle valve 12 is feedback-controlled to a target throttle opening position via the throttle actuator 10. That is, the control unit 4 processes the output signal of the accelerator position sensor 7 in proportion to the depression amount of the accelerator pedal (not shown) of the driver, and moves the throttle actuator to the target throttle opening position corresponding to the depression amount of the accelerator pedal. The feedback control of the throttle valve 12 is performed through the control valve 10.

The transmission and cutoff of power from the crankshaft 21 of the engine 1 to the input shaft 22 of the synchromesh transmission 3 are controlled by the clutch exciting current of the electromagnetic clutch 2. That is, the control unit 4 controls the electromagnetic clutch 2 by the clutch exciting current proportional to the clutch transmission torque.

The synchromesh transmission 3 has, for example, five forward gears and five reverse gears having different gear ratios. The gear shift type transmission 3 is shifted by a feedback control to a target shift speed by a shift / select actuator 5 for gear change. That is, the control unit 4 detects the shift / select position by the shift / select position sensor 6,
The gear shift transmission 3 is feedback-controlled to the target shift speed via the shift / select actuator 5.

The control unit 4 receives a shift lever position signal corresponding to a position operated by the driver from a shift lever 8, an accelerator position sensor signal indicating an accelerator pedal depression amount from an accelerator position sensor 7, and a transmission output. From the shaft rotation sensor 9, the rotation speed of the output shaft 23 and the crankshaft rotation sensor 13
From the rotation speed of the throttle position sensor 14
The throttle opening is input, a gear stage suitable for the vehicle running state is determined by a transmission shift pattern (not shown) (shift start), and the shift / select position sensor 6 determines the shift / select position of the synchromesh transmission 3. While detecting
A control signal is output to the shift / select actuator 5 to perform a shift operation of the synchromesh transmission 3.

Next, the operation of the synchronous automatic transmission according to the first embodiment will be described with reference to the drawings.

FIG. 2 is a diagram showing the relationship between the shift position and the select position in the 2-3 shift control of the synchronous automatic transmission according to the first embodiment of the present invention.

FIG. 3 is a timing chart showing the relationship among the shift position, the select position, the throttle, and the clutch exciting current in the 2-3 shift control of the synchronous automatic transmission according to the first embodiment of the present invention.

As shown in FIG. 3, the throttle closing control
It starts simultaneously with the start of 2-3 shift.

In the case of the control device disclosed in Japanese Patent Application No. 12-175066, the clutch OFF start time Tc is determined from the map of the clutch excitation current value and the engine speed at the shift start point.
And the clutch is turned off after the clutch off start time Tc.

As shown by the clutch excitation current indicated by the chain line or the dashed line at the bottom of FIG. 3, when the shift starts while the clutch excitation current is decreasing or increasing, the clutch excitation current value at the start of the shift is The clutch OFF start time Tc is predicted from the map of the engine rotational speed, and the clutch is turned OFF after Tc. .

When the clutch excitation current at the start of clutch OFF becomes smaller than that at the start of gear shifting, as in the case of the chain line, the clutch OFF is completed earlier than expected, so that a larger deceleration than expected occurs.

When the clutch exciting current at the start of clutch OFF becomes larger than that at the start of gear shifting, as in the case of the alternate long and short dash line, clutch OFF is completed later than expected. Even when the throttle is fully closed and the engine torque is small, the clutch is slightly connected and engine braking occurs, so that a larger deceleration than expected occurs.

On the other hand, in the first embodiment of the present invention,
As shown by the solid line, even when the shift is started while the clutch exciting current value is changing, the estimated clutch OFF completion time is maintained by keeping the clutch exciting current constant from the start of the upshift to the start of the clutch OFF. And the actual clutch OFF completion time is eliminated, and the expected deceleration change reduction effect is obtained.

Thereafter, as shown in FIG. 3, the shift control is started after the throttle is fully closed and the clutch is completely turned off (released).

This shift control is performed in three sections as shown in FIGS. The control section is section A →
Transition is made from section B to section C. As shown in FIG. 2, the section A is a section in which the shift position moves from VY1 to VY4 and the gear is shifted from the second speed in the shift direction. VY2
The section of <shift position <VY3) is a sync area on the pull-out side.

Section B is a section in which the select position moves from VX1 to VX2 and moves in the select direction, as shown in FIG.

As shown in FIG. 2 and FIG.
This is a section in the shift direction when the gear is shifted to the high speed.
This section C is further divided into three sections, namely a section C1 and a section C1.
It is divided into two sections and C3 section.

Section C1 (VY4 <shift position <VY5)
Is a region before entering the synchro, and the shift movement speed is high as shown in FIG.

Section C2 (VY5 <shift position <VY6)
In the synchro area, as shown in FIG. 3, the shift movement speed is slow to smoothly perform the synchro operation.

Section C3 (VY6 <shift position <VY7)
Is a region after the end of the synchro, and the shift movement speed is high as shown in FIG. After the shift control is completed, the throttle is opened again and the clutch is engaged, as shown in FIG.

FIG. 4 is a flow chart showing the operation of the throttle closing control and the clutch OFF control at the start of shifting in the synchronous automatic transmission according to the first embodiment.

In step 100, the control unit 4 determines whether or not a shift has been started in a subroutine of a shift start determination.

Next, in steps 110 to 120,
If the shift is started (YES), the throttle closing speed is determined from the accelerator opening. The accelerator opening is determined from a signal from the accelerator position sensor 7.

"Time A" until the throttle is fully closed
To "(current throttle opening-fully closed throttle opening)
/ Determined throttle closing speed ". The current throttle opening is obtained from a signal from the throttle position sensor 14. The control unit 4 stores the fully closed throttle opening in a memory in advance.

Further, based on the map of the clutch excitation current value and the engine rotation speed, the "clutch OFF time B" is determined from the engine rotation speed and the clutch excitation current value. Further, a "shift flag" and a "clutch excitation current constant request flag" are set. If the shift has not been started (NO), the routine proceeds to step 130. The map of the clutch exciting current value and the engine speed is stored in the memory by the control unit 4 in advance. The engine rotation speed is obtained from a signal from the crankshaft rotation sensor 13.

Next, in step 130, it is determined whether or not the gear is being shifted based on the flag.
In step S), the process proceeds to step 140.
To O), go to step 170.

Next, at step 140, the time A until the throttle is fully closed is compared with the clutch OFF time B. If A <B (YES), the routine proceeds to step 160,
If A ≧ B (NO), the process proceeds to step 150.

Next, at step 150, the time from the start of the shift is compared with the time (AB), and if the time from the start of the shift> (AB) time (YES), step 16 is executed.
0, and if the time from the start of gear shifting ≦ (AB) time (NO), the flow proceeds to step 170.

Next, at step 160, the clutch is turned off, and the clutch exciting current constant request flag is cleared.

Next, at step 170, the throttle opening, that is, the throttle valve 12 is controlled via the throttle actuator 10 so that (current throttle opening-throttle closing speed).

Then, in steps 180 to 190, it is determined that the shift is completed. If the shift is completed (YES), the shift flag is cleared and the process is terminated. If the shift is not completed (NO), the process ends.

FIG. 5 is a flowchart showing the operation of the clutch excitation current instruction control of the synchronous automatic transmission according to the first embodiment.

In step 210, the control unit 4 determines whether or not the clutch exciting current constant request flag is set. If the flag is not set (NO), the process proceeds to step 220, and if the flag is set If (YES), the process ends without performing the process.

In step 220, an instruction value of the clutch excitation current is calculated in the clutch excitation current instruction control.

For this reason, while the clutch exciting current constant request flag is set, the command value of the clutch exciting current at the start of shifting is held, and the clutch is turned off from the start of shifting.
Until the start, the clutch excitation current becomes constant.

As a result, as shown in FIG. 3, the clutch excitation current value at the start of the upshift (at the start of the shift) and the clutch excitation current value at the start of the clutch OFF become the same, so that the clutch OFF time predicted from the map is obtained. There is no difference between the actual clutch OFF time and the expected clutch OF
A sharp deceleration change reduction effect at the time of F is obtained.

The first embodiment reduces a sudden change in the deceleration when the clutch is turned off even when the shift is started in the course of a change in the clutch exciting current value in the synchronous automatic transmission.

[0050]

As described above, the synchronous mesh automatic transmission according to the present invention has an electromagnetic clutch for transmitting or interrupting power from the output shaft of the engine to the input shaft of the synchronous mesh transmission, and an upshift. A control means for controlling the electromagnetic clutch with a constant clutch exciting current from the start to the clutch OFF start is provided. This has an effect that a rapid change in deceleration can be reduced.

As described above, the synchronous mesh automatic transmission according to the present invention uses the accelerator position sensor for detecting the amount of depression of the accelerator pedal and the throttle opening of the throttle valve provided in the intake pipe of the engine. A throttle position sensor to be sought, and a crankshaft rotation sensor for detecting a rotation speed of the engine, wherein the control means is based on signals from the accelerator position sensor, the throttle position sensor, and the crankshaft rotation sensor. Since the clutch exciting current to the electromagnetic clutch is controlled to be constant from the start of the upshift to the start of the clutch OFF, the clutch exciting current is controlled even when the shift is started while the clutch exciting current value is changing. Reduction of sudden deceleration change at OFF An effect that can be.

Further, as described above, in the synchronous automatic transmission according to the present invention, the control means determines the time until the throttle is fully closed based on signals from the accelerator position sensor and the throttle position sensor. The clutch OFF time is calculated based on a signal from the crankshaft rotation sensor, and the clutch excitation current is calculated from the relationship between the time until the throttle is fully closed and the clutch OFF time from the start of the upshift to the start of the clutch OFF. Since the interval is controlled to be constant, even when shifting is started while the clutch exciting current value is changing, there is an effect that a rapid change in deceleration at the time of clutch OFF can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a synchronous automatic transmission according to Embodiment 1 of the present invention.

FIG. 2 is a diagram showing a relationship between a shift position and a select position in 2-3 shift control of the synchronous automatic transmission according to Embodiment 1 of the present invention;

FIG. 3 is a timing chart showing a relationship among a shift position, a select position, a throttle, and a clutch exciting current in the 2-3 shift control of the synchromesh automatic transmission according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating operations of a throttle closing control and a clutch OFF control at the start of shifting in the synchronous automatic transmission according to Embodiment 1 of the present invention;

FIG. 5 is a flowchart showing an operation of clutch exciting current instruction control of the synchronous automatic transmission according to Embodiment 1 of the present invention;

[Explanation of symbols]

Reference Signs List 1 engine, 2 electromagnetic clutch, 3 synchronous mesh transmission, 4 control unit, 5 shift / select actuator, 6 shift / select position sensor, 7 accelerator position sensor, 8 shift lever, 9 transmission output shaft rotation sensor, 10 throttle Actuator, 11 intake pipe, 12 throttle valve, 13 crankshaft rotation sensor, 14 throttle position sensor, 21 engine crankshaft, 22
Input shaft of synchronous mesh transmission, 23 Output shaft of synchronous mesh transmission.

Claims (3)

[Claims] 1. An electromagnetic clutch for transmitting or interrupting power from an output shaft of an engine to an input shaft of a synchronous mesh transmission, and an electromagnetic clutch which supplies a constant clutch exciting current from the start of upshift to the start of clutch OFF. A synchronous mesh automatic transmission, comprising: control means for controlling a clutch. 2. An accelerator position sensor for detecting a depression amount of an accelerator pedal, a throttle position sensor for obtaining a throttle opening of a throttle valve provided in an intake pipe of the engine, and a crankshaft rotation for detecting a rotation speed of the engine. A control unit that controls a clutch excitation current to the electromagnetic clutch based on signals from the accelerator position sensor, the throttle position sensor, and the crankshaft rotation sensor based on signals from the upshift to the clutch OF.
2. The synchronous automatic transmission according to claim 1, wherein the automatic transmission is controlled to be constant until the start of F. 3. The control means calculates a time until the throttle is fully closed based on signals from the accelerator position sensor and the throttle position sensor, and a clutch OFF time based on a signal from the crankshaft rotation sensor. And the time until the throttle is fully closed and the clutch OFF
3. The synchronous automatic transmission according to claim 2, wherein the clutch exciting current is controlled to be constant from the start of the upshift to the start of the clutch OFF based on a time relationship.