JPS61232929A - Device for controlling starting clutch for automatic transmission - Google Patents

Abstract

PURPOSE:To gradually connect a starting clutch from the start of control and obtain a smooth starting condition by providing a control means which outputs a control signal which temporarily increase the clamping pressure of a clutch when a signal for indicating a starting time is inputted. CONSTITUTION:A control unit 15 has an A-D converting circuit 151, a RAM 152, a ROM 153, a CPU 154, a clock circuit 155, and a control signal generating circuit 156. A shift switch 161, a throttle totally closing switch 162, a throttle opening sensor 163, an output shaft rotation sensor 164, an engine speed sensor 165, and a turbine rotation speed sensor 166 are provided as an input sensor. After a high clamping pressure is supplied as a duty of 100% to a starting clutch 12 immediately after starting control, the duty is lowered to a level of controlling creep and, after that, the duty is gradually increased to supply a gradually increasing clamping pressure to the clutch 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a starting clutch control device for an automatic transmission for controlling the clutch engagement pressure of a starting clutch that is engaged at the time of starting.

(Prior Art) As a conventional starting clutch control device, for example, one described in Japanese Unexamined Patent Publication No. 13156/1983 is known.

This conventional device branches a discharge oil passage leading to an oil tank from a supply oil passage that supplies hydraulic pressure to the starting clutch and other starting devices of an automatic transmission, and closes this discharge oil passage in a demagnetized state and closes it in an energized state. In a creep prevention device including a solenoid valve that is opened, the energizing circuit of the solenoid valve is chopped a predetermined number of times when the solenoid valve is returned from an energized state to a demagnetized state.

Therefore, in this conventional device, when the creep prevention device is released from the operating state, the starting clutch is engaged by chopping control (control that repeats 0N-OFF according to a set time and is the same as duty control). This was intended to prevent the shock caused by sudden tightening when starting.

Incidentally, the creep phenomenon is a phenomenon that occurs when a vehicle equipped with an automatic transmission is left in a forward gear position (especially a position with a large gear ratio) while the vehicle is stopped, and the drag torque of the torque converter causes the driver to A creep prevention device refers to a phenomenon in which a vehicle tries to move forward against its will. Under conditions where creep occurs, an automatic transmission is placed in a neutral state or a low gear ratio state to cut off or reduce transmitted torque. A device that prevents the creep phenomenon.

(Problem to be Solved by the Invention) However, in such a conventional device, the starting clutch is gradually connected by chopping control, but in reality, at the beginning of the control, the engagement pressure is There was a problem in that the start-up of the connection was delayed due to the start-up of the clutch plate and the inertial mass of the clutch plate, resulting in engine revving.

(Means for Solving the Problems) The present invention has been made for the purpose of solving the above-mentioned problems, and to achieve this purpose, the present invention employs the following means. .

The solution of the present invention will be described with reference to the conceptual diagram of the claims shown in FIG. 1. The starting clutch 1 is engaged by supplying hydraulic pressure, and the engagement pressure control valve 3 is provided in the hydraulic pressure supply path 2 to the starting clutch 1. and an actuator 4 that controls the operation of the engagement pressure control valve 3, and when a signal (5) indicating the start time is input from the input sensor 5, outputs a control signal to the actuator 4 to gradually increase the clutch engagement pressure. In a starting clutch control device for an automatic transmission comprising a control means 6, the control means 6 includes:
When a signal (S) indicating the time of starting is inputted from the input sensor 5, a control signal (C) which temporarily increases the clutch engagement pressure is outputted.

(Function) Therefore, in the starting clutch control device of the present invention, as described above, when a signal indicating the time of starting is inputted, the control means outputs a control signal that temporarily increases the clutch engagement pressure, thereby controlling the clutch engagement pressure. At the beginning of the start, the starting clutch can be gradually connected from the start of the control without any delay in the rise of the engagement pressure or the rise of the clutch connection.

(Example) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In describing this embodiment, a starting clutch control device that performs a control operation when creep prevention is released in an automatic transmission equipped with a creep prevention device will be taken as an example.

First, the configuration of the embodiment will be explained with reference to FIG.

10 is a starting clutch control device of the embodiment, which includes a torque converter 11, a starting clutch 12, an engagement pressure control valve 13, and a solenoid valve (actuator) 1.
4. It is equipped with a control unit 15 and an input sensor 16, and each configuration will be described below.

The torque converter 11 transmits the rotational driving force from the engine by increasing the torque up to a predetermined rotational state, and has a pump impeller 18 connected to a drive input shaft 17 to which the rotational driving force from the engine is input. , a turbine runner 19 to which the driving force from the pump impeller 18 is transmitted via fluid, and a transmission case 2.
Stator 2 fixed to 0 via a one-way clutch
1, and the turbine runner 19 includes:
The drive output shaft 22 is connected to the drive output shaft 22 .

The starting clutch 12 engages gear elements of a gear train such as planetary gears of an automatic transmission.

This clutch is provided to transmit the driving force from the drive output shaft 22 to the mission output shaft 23 at the time of starting, and includes a clutch drum 24 connected to the drive output shaft 22, and a clutch drum 24 connected to the drive output shaft 22. A clutch plate 25 is provided, a clutch hub 27 is provided with clutch plates 26 arranged at alternate positions, a clutch piston 28 is provided on the clutch hub 27 side, and the clutch piston is a piston chamber 29 to which control hydraulic pressure Pc for operating 28 is supplied;
It is equipped with

Furthermore, the transmission output shaft 23 is attached to the clutch hub 27.
are connected.

The above-mentioned fastening pressure control valve 13 is provided in the middle of a line pressure oil passage 30 to which line pressure PL obtained by regulating the discharge pressure from the oil pump by a pressure regulator valve is provided (a control valve of an automatic transmission). unit), this tightening pressure control valve 13
and the piston chamber 29 of the starting clutch 12 are connected by a control pressure oil passage 31.

The engagement pressure control valve 13 is operated by the balance of oil pressure, and when the solenoid valve 14 provided on the branch oil path 32 of the line pressure oil path 30 is turned off.
In this state, the valve is moved to the right in the drawing because the valve operating pressure PS is low, and the line pressure oil passage 30
The line pressure PL from is drained from the drain oil passage 33, and when the solenoid valve 14 is in the ON state, the valve is moved to the left in the drawing because the valve operating pressure Ps is high, and the line pressure PL is drained to the control pressure oil passage 31. Control oil pressure Pc of line pressure PL
is supplied.

In addition, 34, 35, and 36 in the figure are orifices provided in the hydraulic path.

The solenoid valve 14 is as described above.

It is provided in the branch oil passage 32 of the line pressure oil passage 30,
This solenoid valve 14 is connected to the control unit 1
Among the duty control signals (C) from 5, the energization signal is used to excite the orifice 34 to close it (ON state), and the energization release signal is demagnetized to open the orifice 34 (
OFF state).

The above-mentioned control 22) 15 uses an in-vehicle microcomputer, and includes an A-D conversion circuit 151, an RA
M (random, access, memory) 152. ROM (
read, only, memory) 153. It includes a CPU (central, 3 processing units) 154, a clock circuit 155, and a control signal generation circuit 156.

The input sensor 16 includes a shift switch 161,
Throttle fully closed switch 162. A throttle opening sensor 163, an output shaft rotation speed sensor 164, an engine rotation speed sensor 165, and a turbine rotation speed sensor 166 are provided.

The A-D conversion circuit 151 is connected to each of the sensors 163.1.
Digital signals from 64, 165, 166 (sJL),
This circuit converts (no), (ne), and (nt) into analog signals that can be processed by the CPU 154.

The RAM 152 is a readable and writable memory, and has data for each sensor 161, 162, 163°164.16.
Reading signals from 5,166.

Information is written during the calculation by the CPU 154.

The ROM 153 is a read-only memory,
Information necessary for arithmetic processing by the CPU 154 is stored in advance, and is read out from the CPU 154 as needed.

The CPU 154 is a device that performs arithmetic processing on various input information according to predetermined processing conditions, and processes input information in creep control and starting clutch control.

The clock circuit 155 is a circuit that sets the calculation processing time of the CPU 154.

The control signal generation circuit 156 is a circuit that outputs a duty control signal (C) to the solenoid valve 14, which is an actuator, based on a calculation result signal from the CPU 154.

The shift switch 161 is a switch that detects whether the shift position of the automatic transmission is in the driving range, and outputs an ON signal if it is in the driving range.

The throttle fully closed switch 162 is a switch that detects whether the engine throttle is fully closed (idle state). If the throttle is fully open, an ON signal is output, and when the throttle is open, an OFF signal is output. be done.

The throttle opening sensor 163 is a sensor that detects the throttle opening, and outputs a throttle opening signal (sJl).

The output shaft rotation speed sensor 164 is connected to the mission output shaft 2.
The rotation speed signal (no) is detected by the sensor that detects the rotation speed NO of 3.
is output, and this signal (no) is used as a signal indicating the vehicle speed.

The engine rotation speed sensor 165 is a sensor that detects the rotation speed Ne of the drive input shaft 17, and receives a rotation speed signal (ne).
is output.

The turbine rotation speed sensor 166 is a sensor that detects the rotation speed Nt of the drive output shaft 22, and outputs a rotation speed signal (nt).

Incidentally, in the creep control, the engine speed sensor 17 and the turbine speed sensor 166 perform duty control in which the engagement pressure of the starting clutch 12 is not completely reduced to zero, but is brought into an engagement pressure state that does not reach the level of clutch engagement. By doing so, both sensors 165 are activated when creep control is activated.
, 166, the rotational speed difference is used as an input signal to determine the duty ratio DO so as to obtain a predetermined slip ratio (lower limit value required for creep prevention).

The throttle opening sensor 163 is a sensor used to determine the duty ΔD of the control signal (C) when gradually increasing the engagement pressure of the starting clutch 12, and corresponds to the throttle opening detected by the throttle opening sensor 163. and determine ΔD.

Next, the operation of the embodiment will be explained.

First, the operation of the control device in the embodiment will be explained with reference to the flowchart shown in FIG.

(a) Creep control This creep control is performed from step 100 to step 101.
→Step 102→Step 103→Step 104→
This is performed by progressing the steps from step 105 to step 106.

Incidentally, in step 102, when the throttle is in a fully closed state (idling state), R is used as information indicating the state.
This step is to write a signal of 1 to FLAGI of AM152.

Further, in step 105, when the creep control is in the operating state, the FL of the RAM 152 is stored as information indicating the state.
This step is to write a signal of 1 to AG2.

In other words, the creep control is in the running range (step 100) and the throttle is fully closed (step 101).
), the vehicle speed is zero (step 103), and the control signal (C) of duty Do is output from the state where the control signal (C) of duty 100% is output to the solenoid valve 14 because the vehicle is in the driving range. (C), the engagement pressure of the starting clutch 12 is reduced, the torque transmitted to the transmission output shaft 23 via the starting clutch 12 is reduced, and the creep phenomenon is prevented.

In addition, in this creep control, the engine rotation speed Ne from the engine rotation speed sensor 165 and the turbine rotation speed Nt from the turbine rotation speed sensor 166 are checked to obtain the degree of engagement of the starting clutch 12 necessary for creep prevention. The duty DO of the control signal (C) is determined, and this duty DO is output from the control unit 15 (step 106).

Next, cases in which creep control is not performed will be listed.

■ When the vehicle is in the neutral range or parking range instead of the driving range.

The flow of operation in this case is step 100 → step 1
07→Step 106, and a control signal (C) with a duty of 0% is output.

■ The vehicle is in the driving range, but the throttle is not fully closed (during normal driving).

The flow of operation in this case is step 100 → step 1
01 → Step 108 → Step 109 → Step 11
0→Step 106, and a control signal (c) with a duty of 100% is output.

■ When the vehicle is in the driving range and the throttle is fully closed, but the vehicle speed is not zero (traversing downhill, etc.).

The flow of operation in this case is step 100 → step 1
01 → Step 102 → Step 103 → Step ll
l→Step 106, and if FLAG2 is 1, FLAG2 is set to 0 and the duty is 100%.
A control signal (c) is output.

(b) Creep control release When the throttle fully closed switch 162 is turned OFF, that is, when the accelerator pedal is depressed and the start position is entered, the creep control is canceled and at the same time, the engagement pressure control of the start clutch 12 is started. Ru.

(c) Starting clutch control This starting clutch control has a duty cycle of up to 1 at the time set by the timer after the start, and from the set time Kl to 100% duty.
This is done in three stages: up to 100% duty or higher.

(2) The flow of operations from the start to 1 at the set time is step 100 → step 101 → step 108 → step 112 → step 109 → step 113 → step 114 → step 106.

In this way, in step 108, since 1 has been written in FLAGl as information indicating the idle state in step 102, the process advances to step l12, and in step 112, FLAGI is returned to O and the timer is reset. .

Then, in step 109, it is confirmed whether or not creep control has been performed in advance by checking whether FLAG2=1, and in the next step 113, it is determined whether the time set by the timer is less than or equal to 1, and the process proceeds to step 114. move on.

In step 114, the duty ΔD is reset to O, and the duty is set to 100% while incrementing the timer, and in step 106, the duty 100% control signal (C) is sent from the start to 1 at the set time.
Output.

In other words, when the accelerator pedal is depressed and the fully closed throttle state is released, 1 (for example, if this routine is started every 1 second, 40 sea
up to a certain degree), the duty is controlled at 100% and high engagement pressure is supplied to the starting clutch 12.

(2) The flow of operation from 1 to 100% duty at the set time is step 100 → step 101 → step 108 → step 109 → step 113 → step 115 → step 116 → step 117 → step 106.

In this way, from step 113, the process proceeds to step 115 because the set time Kl has been exceeded, and this step 1
In step 15, the duty is set to duty Do (in the embodiment, DO during creep control) + duty ΔD (calculated according to the throttle opening degree), and in step 117, duty ΔD is gradually increased.

Then, the above-described operation is repeated until the duty reaches 100%.

In other words, as described above, after supplying a high engagement pressure with a duty lOO% to the starting clutch 12 immediately after the start of control, the duty is lowered to the level during creep control, and then the duty is gradually increased. Then, a gradually increasing engagement pressure is supplied to the starting clutch 12.

■ Duty Ioo% or more When the duty reaches 100%, the operation flow is from step 116 to step 118 → step 110 → step 106, and then step 100 → step 101 → step 108 → step 109 → step 110 → step 106. This is the flow in normal driving conditions.

In this way, when the duty reaches 100%, the process proceeds from step 116 to step 118, and FLAG2 is turned on.
The process proceeds from step 110 to step 106, where a control signal (C) with a duty of 100% is output.

After that, the control signal (,C) is output while maintaining the duty at 100%.

That is, the line pressure PL is continued to be supplied to the starting clutch 12 to maintain the engaged state of the starting clutch 12.

The starting clutch control described above operates as shown in the timing chart of FIG. 4.

First, during creep control, the throttle fully closed switch 162 is in the ON state, FLAGl=1, and FLAG
2=1, duty DO.

Then, the throttle fully closed switch 162 changes from ON to OFF.
When it changes to F, creep control is canceled and
Starting clutch control is started, FLAGI becomes 0,
One timer starts incrementing and the duty goes from DO to 100%.

When the set time Kl by the timer has elapsed, the other timer starts incrementing, the duty is suddenly reduced from 100% to DO, and thereafter the duty is gradually increased.

Then, when the duty reaches 100%, FLAG2
becomes 0, and the duty remains at 100%.

Next, changes in the control oil pressure Pc and changes in the engine speed Ne due to the starting clutch control will be explained with reference to a timing chart shown in FIG.

Incidentally, the characteristic shown by the dotted line in the figure is the characteristic when the duty is gradually increased in the starting clutch control without temporarily issuing a control signal with a duty of 100% at the start of the control.

As is clear from this characteristic diagram, regarding the control oil pressure Pc, there is an increase in the control oil pressure PC at the beginning of the control, and the engine speed Ne does not rise suddenly at the beginning of the control, as shown by the characteristic shown by the dotted line. It exhibits the characteristic that it rises gradually.

In other words, when the engine speed Ne suddenly increases at the beginning of the control, it is because the engine is revving. This delay was eliminated by outputting a 100% duty control signal (C) at the start of control, improving the responsiveness of the oil pressure and preventing the occurrence of engine compartment bloom due to the characteristics of the engine speed Ne. It is clear from this.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention may be modified without departing from the gist of the present invention. included.

For example, in the embodiment, the starting clutch control device is used when starting after canceling the creep control, but the starting clutch control device may be used when starting after shifting from the normal neutral state to the drive state, etc. .

Further, in the embodiment, a creep control device that leaves a slight engagement pressure due to the duty DO during creep control is shown, but it is possible to apply it to a creep control device that reduces the engagement pressure to zero, as in the conventional example. Of course.

Further, in the embodiment, an example of oil pressure control using duty control is shown, but oil pressure control may be performed using variable oil pressure obtained by directly controlling the oil pressure supplied to the starting clutch.

(Effects of the Invention) As explained above, the starting clutch control device of the present invention includes a control means that outputs a control signal to temporarily increase the clutch engagement pressure when a signal indicating the first start is input. As a result, the starting clutch can be gradually connected from the beginning of the control to achieve a smooth starting state without causing the engine compartment to bulge due to a delay in hydraulic response at the beginning of the control.

[Brief explanation of drawings]

Fig. 1 is a conceptual diagram of a claim showing a starting clutch control device for an automatic transmission according to the present invention, Fig. 2 is an overall view showing a starting clutch control device of an embodiment, and Fig. 3 is an operation of the control unit in the embodiment device. 4 is a timing chart of the starting clutch control in the embodiment device, and FIG. 5 is a timing chart of the control oil pressure characteristics and engine rotation speed characteristics obtained by the starting clutch control in the embodiment device. be. l... Starting clutch 2... Hydraulic pressure supply path 3... Engaging pressure control valve 4... Actuator 5... Input sensor 6... Control means (S)... Starting signal (e) ...Control signal patent application Nissan Motor Co., Ltd.

Claims (1)

[Scope of Claims] 1) A starting clutch that is engaged by supplying hydraulic pressure, an engagement pressure control valve provided in a hydraulic pressure supply path to the starting clutch, and an actuator that controls the operation of the engagement pressure control valve. a control means that outputs a control signal to the actuator to gradually increase the clutch engagement pressure when a signal indicating the time of starting is input from the input sensor;
A starting clutch control device for an automatic transmission, characterized in that the control means is a means for outputting a control signal to temporarily increase clutch engagement pressure when a signal indicating the time of starting is input from an input sensor. Automatic transmission starting clutch control device.