JP2002323068A - Clutch control device for synchronous meshing type automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a protrusive sense and the blow-up of an engine during braking by correcting the amount of a clutch exciting current in accordance with vehicle speed when detecting a braking state. SOLUTION: The clutch control device is provided with a clutch capable of changing power transmission and interruption by an exciting current when starting a speed change and ending a speed change, a brake switch detecting the state in which a brake pedal is depressed, a range switch detecting a traveling range either in a neutral range or in a reverse range, an acceleration position sensor detecting acceleration pedal stepped quantity and a vehicle speed sensor which detects vehicle speed. When detecting a shift from a creep traveling state to a braking state by the brake switch, the amount of the clutch exciting current is corrected in response to the vehicle speed, thereby suppressing the protrusive sense during braking caused by oversized transmission torque and preventing the blow-up of an engine speed caused by a quick clutch-off operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch control device for an automatic transmission of the synchronous mesh type, and more particularly to a clutch control device for effectively shifting clutch transmission torque from a creep running state to a braking state to improve the feeling of protrusion. The present invention relates to a clutch control device for a synchronous-meshing automatic transmission that prevents an engine from blowing up.

[0002]

2. Description of the Related Art Conventionally, as a control device of a synchronous mesh type automatic transmission, there is a control device which is referred to in Japanese Patent Application Laid-Open No. 6-159398. Or a creep current value using vehicle speed as a variable, and the creep current value is supplied to the electromagnetic powder clutch.

[0003] However, when the brake pedal is depressed and stopped during creep running, a feeling of protrusion occurs if the clutch transmission torque is maintained as it is. Further, if the clutch transmission torque is rapidly reduced, the engine speed may be increased.

[0004]

As described above, the conventional control device for a synchronous mesh type automatic transmission uses the clutch transmission torque as it is when the brake pedal is depressed and stopped during creep running. However, there is a problem that a sense of protrusion is generated, and if the clutch transmission torque is rapidly reduced, the engine speed may be increased.

The present invention has been made to solve such a problem. When a braking state is detected from a creep running state, a clutch exciting current amount is corrected in accordance with a vehicle speed, so that a braking operation is performed. A control device for a synchronous-meshing automatic transmission is provided which can prevent a feeling of protrusion and can prevent an engine from blowing up when a clutch is suddenly turned off.

[0006]

SUMMARY OF THE INVENTION The present invention provides a clutch capable of changing power transmission / interruption by an excitation current at least at the start and end of a shift, and a brake switch for detecting a state in which a brake pedal is depressed. And, a range switch that detects whether the traveling range is a neutral range or a reverse range, an accelerator position sensor that detects an accelerator pedal depression amount, a vehicle speed sensor for detecting a vehicle speed, based on detection signals of the various sensors, A clutch excitation current amount control means for controlling a clutch excitation current amount applied to the clutch,
The clutch exciting current amount control means includes a creep current reference value calculating means for calculating a clutch exciting current reference value during creep running, and the creep running when a transition from a creep running state to a braking state is detected by the brake switch. And a correction amount calculating means for calculating a correction amount with respect to the clutch exciting current reference value at the time.

The correction amount for the clutch excitation current reference value is calculated by a predetermined function of the vehicle speed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram schematically showing a first embodiment of the present invention. In FIG. 1, a synchronous mesh automatic transmission 3 is connected to a crankshaft 21 of an engine 1 via an electromagnetic clutch 2.

The control unit 4 includes a microcomputer having various arithmetic functions, and controls the engine 1 based on various sensor information indicating the operating state of the engine 1.
The electromagnetic clutch 2 and the synchronous automatic transmission 3 are controlled.

The shift / select actuator 5 drives the synchronous automatic transmission 3 under the control of the control unit 4. Shift / select position sensor 6
Detects the actual shift / select positions VY and VX of the synchromesh automatic transmission 3 and inputs them to the control unit 4.

A fourth speed gear 44 functioning as a primary gear is directly connected to the input shaft 22 of the synchronous automatic transmission 3. After the fourth gear 44, the third gear 43, the second gear 42, the first gear 41, the fifth gear 45
And a reverse gear 46 are sequentially arranged.

Three sleeve gears 100 are arranged between the gears 41 to 46. Each sleeve gear 100
Is the output shaft 3 of the synchromesh automatic transmission 3
2 and is movable in the axial direction.

Each of the gears 41 to 46 forms a set with a gear directly connected to the counter shaft 31 provided side by side with the output shaft 32, and is always meshed with a gear on the counter shaft 31.

With the above configuration, the output shaft 3
2 are each gears 41 to 46 via the sleeve gear 100
Is directly connected to the input shaft 22.

In this case, the synchromesh automatic transmission 3 is a countershaft type five-speed gear transmission, which includes five forward gear sets having different gear ratios, one reverse gear set, and a gear mesh state. And three sleeve gears for switching.

The fourth gear 44 on the input shaft 22
Is provided with an input rotation speed sensor 7 for detecting an input rotation speed Ni of the synchronous meshing automatic transmission 3.
The output shaft 32 is provided with an output rotation speed sensor (vehicle speed sensor) 8 for detecting the output rotation speed of the synchromesh automatic transmission 3 as the vehicle speed Vr.

The intake pipe 10 of the engine 1 is provided with a throttle valve 11 driven by a throttle actuator 12. Throttle position sensor 9
Detects the opening degree θ of the throttle valve 11.

The accelerator position sensor 13 outputs a signal proportional to the amount of depression of an accelerator pedal (not shown) by the driver as an accelerator opening α as the control unit 4.
To enter.

The control unit 4 processes the output signal of the accelerator position sensor 13, calculates a target throttle opening θo corresponding to the accelerator opening α, and performs feedback control of the throttle opening θ to obtain θ = θo. Thus, the throttle valve 11 is driven via the throttle actuator 12.

The shift lever (range switch) 14 is
The shift position operated by the driver (for example, P,
R, N, and D) are input to the control unit 4. The engine rotation speed sensor 15 detects the rotation speed N of the engine 1.
e is detected and input to the control unit 4.

Reverse gear 46 in the synchronous automatic transmission 3
Is provided with a reverse gear switch 16 to detect the operating state of the reverse gear. Brake switch 17
Inputs to the control unit 4 a signal indicating a brake operation state while the driver is depressing a brake pedal (not shown).

The control unit 4 includes clutch exciting current amount control means for controlling the amount of clutch exciting current applied to the electromagnetic clutch 2, and at least at the start and end of shifting, a synchronous mesh type automatic transmission from the crankshaft 21 of the engine 1. Transmission / cutoff of power to the input shaft 22 of the transmission 3 is automatically changed by a clutch exciting current amount proportional to the clutch transmission torque.

The clutch exciting current amount control means in the control unit 4 includes a creep current reference value calculating means for calculating a clutch exciting current reference value during creep running, and a correction amount for the clutch exciting current reference value during creep running during vehicle speed. And a correction amount calculating means for calculating the correction value using a predetermined function described later, and when the brake switch 17 detects a transition from the creep running state to the braking state, the clutch exciting current amount is corrected by the correction amount.

FIG. 2 is a block diagram conceptually showing the relationship between the shift / select actuator 5 and the shift / select position sensor 6 in FIG. 2, the shift / select actuator 5 includes a shift motor 51 and a select motor 52, and a shift motor 51.
Reducer 53 provided on the output shaft of
And a speed reducer 54 provided on the second output shaft.

The shift / select position sensor 6
A shift position sensor 61 associated with the shift motor 51 and the speed reducer 53 and a select position sensor 62 associated with the select motor 52 and the speed reducer 54 are provided.

The shift position sensor 61 and the select position sensor 62 detect the position in the direction of the arrow with the neutral gear position in FIG. 2 as the center.

FIG. 3 shows the shift position sensor 6 shown in FIG.
FIG. 6 is a characteristic diagram illustrating a relationship between a shift position and a detection signal VY (voltage value) according to a first example.

In FIG. 3, a voltage learning value VYA corresponding to the shift position at the first, third, and fifth speeds, a voltage learning value VYB corresponding to the shift position at the time of neutral, and 2
Learning value V corresponding to the shift position at the time of speed, 4th speed, reverse
YC is shown.

FIG. 4 is a characteristic diagram showing the relationship between the shift position by the select position sensor 62 in FIG. 2 and the detection signal VX (voltage value).

In FIG. 4, a voltage learning value VXA corresponding to the select position at the first speed and the second speed, a voltage learning value VXB corresponding to the select position at the third speed and the fourth speed (including the neutral position), 5 shows the voltage learning value VXC corresponding to the select position at the time of the fifth speed and reverse.

Next, a general shift operation according to the first embodiment of the present invention shown in FIGS. 1 and 2 will be described. The electromagnetic clutch 2 is driven by a clutch exciting current proportional to the clutch transmission torque under the control of the control unit 4 to transmit and cut off power from the crankshaft 21 of the engine 1 to the input shaft 22 of the stepped transmission 3. Do.

The shift / select actuator 5 selects the connected state of the sleeve gear 100 under the control of the control unit 4 and switches the gear of the synchronous automatic transmission 3. The rotation input to the synchromesh automatic transmission 3 is first transmitted to the counter shaft 31 via the fourth speed gear 44 (primary gear) on the input shaft 22.

The sleeve gear 100 has a transmission path and a speed ratio ((gear ratio of the fourth speed gear 44 × gear ratio of each speed gear) depending on which one of the gears 41 to 46 disposed on the output shaft 32 is selected. ).

For example, in the fourth speed, the input shaft 22 and the output shaft 32 are directly connected by connecting the sleeve gear 100 to the fourth speed gear 44.

At the time of shifting, first, the shift operation of the sleeve gear 100 is performed to perform an opening operation for releasing the mechanical meshing state of the gears of the current speed stage. A coupling operation for meshing with each other is performed. The state in which the reverse gear 46 is engaged is detected by the reverse gear switch 16.

The control unit 4 includes a switch (shift position) signal corresponding to the operation position of the shift lever 14, an accelerator opening α from the accelerator position sensor 13, an engine speed Ne from the engine speed sensor 15, and The vehicle speed Vr from the output rotation speed sensor 8;
A switch signal corresponding to a brake operation position from the brake switch 17 is fetched.

The gear position control means in the control unit 4 detects the shift / select positions VY and VX from the shift / select position sensor 6 and shifts the vehicle to a running state based on a transmission shift pattern (not shown). A suitable gear position is determined, and a control signal for the shift / select actuator 5 is output.

As a result, the synchronous automatic transmission 3
A shift operation is performed by the opening operation and the coupling operation.
The synchronization state of the sleeve gear 100 at the time of shifting is detected based on the correlation between the input rotation speed Ni and the vehicle speed Vr.

At the time of shifting, the control unit 4 throttles the throttle valve 11 to a predetermined opening by the throttle actuator 12, turns off the exciting current of the electromagnetic clutch 2 and turns the stepped transmission 3 into the power off state. The gear is switched.

In the shift control, the control unit 4 in which the creep current value is set so as to reach the creep target vehicle speed has a shift position sensor 61 (FIG. 2).
The shift drive is performed via the speed reducer 53 by the shift motor 51 in the shift / select actuator 5 while performing feedback control on the shift position VY from the shift position VY.

Similarly, in the select control, the control unit 4 performs feedback control of the select position VX from the select position sensor 62,
Select drive is performed by a select motor 52 in the shift / select actuator 5 via a speed reducer 54.

Next, referring to FIGS. 5 and 6, FIG.
The operation during creep control according to the first embodiment of the present invention shown in FIG. 2 will be described. FIG. 5 is a flowchart showing the operation of calculating the clutch excitation current value during creep running.

In FIG. 5, first, in step S100, the control unit 4 calculates a clutch excitation current reference value during creep running (hereinafter referred to as a creep current reference value). Specifically, a creep current reference value is obtained by performing feedback control by PID control based on the creep target vehicle speed and the actual vehicle speed.

Next, in step S110, it is determined whether or not the brake switch 17 indicates an ON state.

If it is determined in step S110 that the brake switch 17 is in the ON state (ie, YES), in the next step S120, a predetermined function relating to the vehicle speed expressed by the following equation (1) is used to determine the creep current reference value. A correction amount is calculated, and a value obtained by subtracting the correction amount from the creep current reference value is set as a clutch excitation current value.

Correction amount = (vehicle speed at start of ON of brake switch−current vehicle speed) × KILTVS (1) (KILTVS is an arbitrary set value.)

On the other hand, if it is determined in step S110 that the brake switch 17 is off (that is, NO), the process proceeds to step S130, and the clutch exciting current value is set as the creep current reference value.

FIG. 6 is a timing chart showing a change in the clutch exciting current when the brake switch 17 is turned on from the creep running state to be in the braking state.

As described above, in the present invention, when the braking state is detected from the creep running state, the clutch exciting current amount is corrected according to the difference between the vehicle speed at the start of braking and the current vehicle speed. In addition, it is possible to prevent the feeling of protrusion during braking due to excessively large transmission torque, and to prevent the engine speed from rising due to the sudden turning off of the clutch.

[0050]

According to the present invention, there is provided a clutch capable of changing the transmission / interruption of power by an exciting current at least at the start and end of a shift, and a brake switch for detecting a state in which a brake pedal is depressed. And, a range switch that detects whether the traveling range is a neutral range or a reverse range, an accelerator position sensor that detects an accelerator pedal depression amount, a vehicle speed sensor for detecting a vehicle speed, based on detection signals of the various sensors, Clutch exciting current amount control means for controlling the amount of clutch exciting current applied to the clutch, wherein the clutch exciting current amount control means comprises a creep current reference value calculating means for calculating a clutch exciting current reference value during creep running. From the creep running state to the braking state by the brake switch. And a correction amount calculating means for calculating a correction amount to the reference value of the clutch exciting current during the creep running. When the state is detected, the clutch exciting current amount is corrected, so that it is possible to prevent a feeling of protrusion during braking due to excessively large transmission torque, and to prevent the engine speed from rising due to the clutch being quickly turned off. Can be prevented.

The correction amount for the clutch excitation current reference value is calculated by the above-mentioned predetermined function of the vehicle speed.
To correct the clutch excitation current according to the current vehicle speed,
It is possible to prevent a feeling of protrusion and prevent the engine from blowing up.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing a clutch control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram conceptually showing a relationship between a shift / select actuator and a shift / select position sensor in FIG.

FIG. 3 is a characteristic diagram illustrating a relationship between a shift position and a detection voltage by a shift position sensor in FIG. 2;

FIG. 4 is a characteristic diagram showing a relationship between a shift position and a detection voltage by a select position sensor in FIG. 2;

FIG. 5 is a flowchart showing a clutch excitation current value calculation process during creep control according to the first embodiment of the present invention.

FIG. 6 is a timing chart showing a change in a clutch exciting current at the time of transition from a creep running state to a braking state according to the first embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 1 engine, 2 electromagnetic clutch, 3 synchronous automatic transmission, 4 control unit, 5 shift / select actuator, 6 shift / select position sensor, 7 input rotational speed sensor, 8 output rotational speed sensor, 13 accelerator position sensor, 14 Shift lever, 15 engine speed sensor, 16 reverse gear switch, 17 brake switch, 21 crankshaft, 22 input shaft, 31 counter shaft, 32 output shaft, 41 1st gear, 4th gear
2 2nd gear, 43 3rd gear, 44 4th gear, 45
5th gear, 46 reverse gear, 51 shift motor, 52
Select motor, 53, 54 Reduction gear, 61 Shift position sensor, 62 Select position sensor,
100 Sleeve gear.

Claims (2)

[Claims] 1. A clutch capable of changing power transmission / interruption by an exciting current at least at the start and end of a shift, a brake switch for detecting a state in which a brake pedal is depressed, and a travel range or a neutral range. A range switch for detecting a reverse range, an accelerator position sensor for detecting an accelerator pedal depression amount, a vehicle speed sensor for detecting a vehicle speed, and a clutch excitation current applied to the clutch based on detection signals of the various sensors. A clutch exciting current amount controlling means for controlling the amount of clutch exciting current, the clutch exciting current amount controlling means comprising: a creep current reference value calculating means for calculating a clutch exciting current reference value during creep running; and a creep running state by the brake switch. When the transition of the braking state is detected from Control device for synchromesh automatic transmission characterized in that it includes a correction amount calculation means for calculating a correction amount for the clutch exciting current reference value during the creep running. 2. The control device for a synchronous automatic transmission according to claim 1, wherein the correction amount for the clutch excitation current reference value is calculated by a predetermined function of the vehicle speed.