JPS63195455A - Automatic transmission device for gear transmission - Google Patents

Abstract

PURPOSE:To eliminate the shift up action on a downhill road so as to effectively apply engine brake, by controlling a device so as to decide a downhill in a control unit being based on the first signal from an accelerator switch and a speed increase signal from a car speed sensor. CONSTITUTION:When it is determined that vehicle speed is increasing further with no depression of the accelerator, the CPU5e decides a vehicle to be in running on a downhill road, even if the vehicle speed increases, the CPU5e outputs no shift up instruction signal, stored in memory in accordance with an automatic speed change diagram, to a shift actuator 6 and a select actuator 7 but an instruction to maintain gear meshing condition of the present speed change shift is issued, to the actuators 6, 7. While in case of more effectively applying engine brake on the downhill road, since the vehicle, decreasing its speed by depressing the brake, it released from the decision of the downhill road, the CPU5e, which outputs a shift down instruction signal to the actuators 6, 7, in accordance with the automatic speed change diagram corresponding to the vehicle speed at that time, performs a shift down to a further lower speed change shift.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an improvement in an automatic transmission in a gear transmission for an automobile, and in particular to an automatic transmission that can effectively apply engine braking even on downhill slopes. It is related to the device.

(Prior art and its problems) Conventionally, in an automatic transmission device for a gear transmission, automatic shifting is performed by electronic control based on an automatic shifting diagram as shown in FIG. 4, for example. shows an automatic shift diagram in the D range (drive), and the vertical line in the figure is an automatic shift diagram at the time of upshifting. Also, A, B,
C, D, and E indicate the first speed region, second speed region, third speed region, -4th speed region, and fifth speed region, respectively.

The automatic transmission diagram shown in FIG. 4 is stored in advance in the control unit of the automatic transmission, and is based on the accelerator opening signal from the accelerator opening sensor and the vehicle speed sensor, which are separately input to the control unit. Based on the vehicle speed signal input from the control unit, a shift point based on such an automatic shift diagram is determined in the control unit, and the control unit issues a shift command signal to the shift actuator and select actuator attached to the gear transmission. is emitted, and the meshing of the gears in the gear transmission is changed.

In automatic shifting based on such an automatic shifting diagram, on a downhill slope, as shown by straight line R in Figure 4, the vehicle speed increases rapidly even when the accelerator pedal is not depressed at all, so it is important to note that )-a, the vehicle is automatically shifted up from 1st gear to 2nd gear, and when the vehicle speed further increases and passes point b, it is similarly shifted up from 2nd gear to 3rd gear, and then shifted up to point c. , d is automatically shifted up to 4th and 5th gears.

In this way, in the conventional structure, when the select lever is in the D range even when going downhill, the automatic transmission operates and upshifts according to the automatic shifting diagram. There was a problem in that the engine brake did not work and was dangerous.

(Means for Solving the Problems) The present invention has been devised in view of the above-mentioned conventional problems, and an object of the present invention is to provide an automatic transmission device that can eliminate upshifting and do not apply engine braking on downhill slopes. The purpose is to determine the shift point according to a pre-stored automatic shift diagram based on the accelerator pedal depression signal input from the accelerator opening sensor and the vehicle speed signal input from the vehicle speed sensor. An automatic transmission device for a gear transmission, which is equipped with a control unit that issues a gear change command signal to an actuator that selects a meshing position of the gear transmission, and includes an accelerator switch that detects the ON/OFF state of an accelerator; A downhill slope is determined within the control unit based on the input signal from the switch and the amount of change in the vehicle speed signal from the vehicle speed sensor, and control is performed so as not to shift up when the downhill slope is determined.

(Function) On a downhill slope, the driver takes his foot off the accelerator, so the accelerator switch installed on the accelerator pedal turns OFF, and a signal indicating that the accelerator is OFF is input from the accelerator switch to the control unit. When the vehicle speed increases rapidly in this state, the amount of increase in vehicle speed is detected by the vehicle speed signal from the vehicle speed sensor, and the control unit determines that it is a downhill slope. The upshift according to the automatic shift diagram stored in the internal memory is interrupted, and a command is output to the actuator to fix the gear transmission at the current shift position without upshifting, so the select lever does not automatically shift when going downhill. position(
Even when the engine is in the D range, engine braking can be effectively applied without increasing vehicle speed unnecessarily.

(Example) Hereinafter, one embodiment of the present invention will be described based on the drawings.

Figure 1 shows a schematic diagram of the automatic transmission of a gear transmission, and Figure 2 shows the configuration of the control unit in the equipment.
FIG. 3 shows the control program within the Kodotrol unit.

In the figure, a gear-type transmission 1 connected to an engine E
includes a shift actuator 6 and a select actuator 7, which are a set of hydraulic cylinders that can change the meshing of the gears in the gear transmission 1, and a hydraulic cylinder that can connect and disconnect the clutch interposed between the engine E and the gear transmission 1. A set of clutch actuators 8 are provided, and the engine E is provided with a throttle actuator 10 that can adjust the opening degree of the throttle. The shift actuator 6 can change gears in the shift direction shown in FIG. 5, while the select actuator 7 can change gears in the select direction shown in FIG.

These shift actuator 6, select actuator 7, clutch actuator 8, and throttle actuator 10 are operated based on command signals from a control unit 5 composed of a microcomputer. ．． Accelerator opening sensor 3. Accelerator switch 4.
Select lever 11. The configuration is such that each signal from the engine rotation sensor 9 is input.

The select lever 11 is installed in the vehicle interior, and is selected to any position such as D range (drive), reverse 1st gear, or 2nd gear based on the driver's intention. A contact switch is provided at the position, and a select position signal from the contact switch is input to the control unit 5. When the select lever 11 is set to the D range (drive), automatic speed change operation is performed, and at other positions, manual speed change operation similar to the conventional one is performed.

Further, the accelerator opening sensor 3 detects the amount of depression of the accelerator pedal by the driver, and is composed of a potentiometer or the like, and inputs an accelerator opening signal into the vehicle control unit 5. Further, an engine rotation sensor 9 is installed on the crankshaft of the engine E, and inputs the rotation speed of the crankshaft to the control unit 5.

Furthermore, the vehicle speed sensor 2 is provided on the output shaft of the gear transmission 1, etc., and inputs a vehicle speed signal to the vehicle control unit 5.

The accelerator switch 4 is installed below the accelerator pedal and consists of a normal ON/OFF switch, etc., and is turned ON when the driver's foot is on the accelerator pedal, and the foot is removed from the accelerator pedal. The ON/OFF state of the accelerator is input to the control unit 5.

Further, the throttle actuator 10 is constituted by a stepping motor and is connected to a throttle valve shaft, so that the throttle valve can be opened and closed by rotation of the stepping motor.

The shift actuator 6, select actuator 7, and clutch actuator 8 each include a hydraulic cylinder and a solenoid valve that drives the hydraulic cylinder, and each solenoid valve is activated based on a command signal from the control unit 5. Each hydraulic cylinder is operated by turning it on and off and switching the hydraulic boat using a solenoid valve.

The control unit 5 has a structure as shown in FIG. 2, and includes a pulse input circuit 5 that inputs pulse signals from the vehicle speed sensor 2 and the engine rotation sensor 9.
a, an analog input circuit 5b that inputs an analog signal from the accelerator opening sensor 3, a contact input circuit 5c that inputs position and status signals from the select lever 11 and the accelerator switch 4, and, for example, an 8-bit p micro A CPU 5e comprising a computer, a step motor drive circuit 5f that outputs a drive command signal to the throttle actuator 10, and an electromagnetic valve drive circuit that outputs an operation command signal to the shift actuator 6, select actuator 7, and clutch actuator 8. In the analog input circuit 5b, the input signal is converted into a digital signal by an AD converter and input to the CPU 5e, and the contact input circuit 5c is connected to the CPU 5e via a multiplexer 5d.
It has a structure that supplies signals to 5e.

In such a structure, an automatic shift diagram that can determine shift points as shown in FIG. 4, for example, is stored in the CPUSe, and the select lever 11 is set to D.
When the range is selected, the control unit 5 performs automatic speed change control based on the stored automatic speed change diagram, and appropriately issues an operation command signal to the actuator 6.7.8.

For example, when a shift command is issued based on an automatic shift diagram, a command is first issued to the throttle actuator 10 to operate the throttle of the engine E in the closing direction, and the engine speed is reduced by the operation of the throttle actuator 10. Immediately before the vehicle shifts from the acceleration state to the coasting state (determined by the input signal from the engine rotation sensor 9), a command signal to disengage the clutch is issued to the clutch actuator 8, and the clutch actuator 8 operates to disengage the clutch. is disconnected.

After that, a shift command based on the automatic shift diagram is issued to the shift actuator 6 and select actuator 7, and the shift actuator 6 controls the shift direction and the select actuator 7 controls the select direction, and the gears are shifted to a predetermined gear position. and shift. After that, a connection command is issued to the clutch actuator 8, and the clutch actuator 8 operates to connect the clutch. At the same time, a command is issued to the throttle actuator 10 to open the throttle position to a position that matches the amount of depression of the accelerator pedal (based on the input signal from the accelerator opening sensor 3), and the throttle position is adjusted. Such an operation command is issued every time the gear is changed, and the gear shifting operation is performed in the same flow as the operation normally performed by a driver when changing gears.

Incidentally, in this example, the shift commands to the shift actuator 6 and the select actuator 7 are performed according to the program shown in FIG.

That is, the CPU 5e in the control unit 5 receives the vehicle speed value from the vehicle speed sensor 2 and the accelerator opening sensor 3.
The accelerator opening value is read (step 1), and then it is determined whether the select lever 11 is in the D range (drive position) (step 2). If the select lever 11 is in the D range, then the CPU 5e determines whether the vehicle speed is increasing based on the vehicle speed from the vehicle speed sensor 2 (step 3). Furthermore, it is determined whether or not the accelerator is depressed based on a signal from the accelerator switch 4 (step 4). When it is determined in step 3 that the vehicle speed is increasing and that the accelerator is not depressed in step 4, the CPU 5e determines that the vehicle is traveling downhill and increases the vehicle speed. A command to maintain the engaged state of the gears of the current gear without outputting a shift up command signal to the shift actuator 6 and select actuator 7 in accordance with the automatic transmission diagram that is also stored. is served.

When it is determined in step 3 that the vehicle speed is not increasing, or when it is determined in step 4 that the accelerator is being depressed, a shift up command signal is sent to the shift actuator according to the stored automatic shift diagram. 6. The signal is output to the select actuator 7 (step 6), and the hydraulic cylinders of the shift actuator 6 and select actuator 7 are operated to change the meshing of the gears of the gear transmission 1 (step 8).

Further, in step 2, when it is determined that the select lever 11 is located at a select position other than the D range, the CPU 5e drives the shift actuator 6 and the select actuator 7 to select, for example, the reverse gear. A command signal is issued (step 7), the shift actuator 6 and the select actuator 7 are operated, and the gears are engaged to the backward position (step 8).

Also, if the driver wants to make the engine brake more effective when going downhill, the driver can step on the brake.
Since the vehicle speed decreases and the downhill slope determination in step 3 is canceled, in step 6 a shift down command signal is sent from the CPU 5e to the shift actuator 6. The signal is output to the select actuator 7 and is shifted down to a lower gear. When the driver releases the brake when the gear has been downshifted to the desired gear, it is determined that the slope is downhill again in steps 3 and 4, so that gear is maintained and the vehicle descends while applying engine braking. Can run on hills.

For example, if you are currently in 4th gear and entering a downhill slope, it is assumed that you will be traveling downhill in 4th gear from step 5.
Furthermore, if you apply engine braking and try to drive downhill in 3rd gear, pressing the brake will slow down the vehicle and automatically shift down to 3rd gear, so if you then release the brake, Third gear allows you to apply engine braking to drive downhill.

In this way, in this example, the select lever 11 is
In the same way as driving downhill with the engine brake activated by selecting the 2nd gear position or the 2nd gear position, the select lever 1
It is possible to travel downhill with the engine brake effectively applied while the vehicle is left in the D range, and it is also possible to travel downhill with the vehicle always in the D range.

(Effects of the Invention) The automatic transmission device for a gear transmission according to the present invention receives an accelerator pedal depression amount signal input from an accelerator opening sensor;
Based on the vehicle speed signal input from the vehicle speed sensor,
In an automatic transmission device for a gear transmission, which is equipped with a control unit that determines a shift point according to a pre-stored automatic shift diagram and issues a shift command signal to an actuator that selects a meshing position of the gear transmission, turning on the accelerator.

An accelerator switch that detects an OFF state is provided, and a downhill slope is determined within the control unit based on the input signal from the accelerator switch and the amount of change in the vehicle speed signal from the vehicle speed sensor, and when it is determined that the downhill slope is By controlling the vehicle so as not to shift the vehicle, it is possible to effectively apply the engine brake while driving downhill while keeping the select lever in the D range.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Fig. 1 is a schematic configuration diagram of an automatic transmission of a gear transmission, Fig. 2 is a block diagram of the configuration of the control unit in Fig. 1, and Fig. 3 is a block diagram of the control unit in Fig. 2. CP of
A flowchart diagram showing a control program in U,
Figure 4 is an automatic transmission diagram stored in advance in the CPU;
The figure is a shift direction diagram showing a shift direction and a select direction. E...Engine 1...Gear transmission 2...
・Vehicle speed sensor 3...Accelerator opening sensor 4...Accelerator switch 5...Control unit 6...Shift actuator 7...Select actuator 8...Clutch actuator 9...Engine rotation sensor 10・...Throttle actuator 11...Select lever 5e=CPU Patent applicant Aichi Kikai Kogyo Co., Ltd. Agent Patent attorney Yoshihisa Shimizu Figure 3 Drawing No. 2 No drawing X-ref F Hoji Figure 5

Claims (1)

[Claims] Based on the accelerator pedal depression signal input from the accelerator opening sensor and the vehicle speed signal input from the vehicle speed sensor, the shift point is determined according to a pre-stored automatic shift diagram, and the meshing position of the gear transmission is determined. In an automatic transmission device for a gear transmission equipped with a control unit that issues a shift command signal to an actuator that selects a
An accelerator switch that detects the ON/OFF state of the accelerator is provided, and based on the input signal from the accelerator switch and the amount of change in the vehicle speed signal from the vehicle speed sensor, a downhill is determined in the control unit, and the downhill is detected. An automatic transmission device for a gear transmission, characterized in that when it is determined that the gear transmission does not shift up, it performs control according to the automatic transmission diagram so as not to shift up.