JPS61238533A - Controller for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent the occurrence of sudden starting due to wrong operation by a driver, by installing a controlling device which outputs a shift change signal corresponding to a driving shift position of a car only at a time when a brake is in operation and a signal is inputted. CONSTITUTION:A controlling device 20 is one that controls an automatic transmission 1 according to a driving state and it is provided with a central processing unit 21, a read-only memory 22 and a random access memory 23. And, a revolving position sensor 8, a shift operation detector 10, a car speed sensor 11, a foot brake sensor 12 and the like are all connected to an input- output circuit 24 of this controlling device 20, while an input signal is fed to the CPU 21, and furthermore a control signal controlling a DC motor 6 is outputted to a motor control circuit 25 from the circuit 24. And, a fact that a revolving position of a control shaft 3 to be fed out of the sensor 8 enters a zone of drive D or the desired position is judged whereby braking signal is fed to a circuit 25, applying a dynamic brake to a motor 6.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for an automatic transmission mounted on an automobile, and particularly to improving safety when starting the automobile.

(Prior Art) In a vehicle equipped with a conventional automatic transmission (hereinafter referred to as an AZT vehicle), the driver performs the following actions for starting the vehicle. First, turn on the ignition key to start the engine, press the matte brake and switch the shift position control lever, for example, from the parking range to the drive range, then press the foot brake and accelerate. The vehicle is then started by stepping on it.

However, in the above-mentioned starting operation, if the driver misidentifies the foot brake as the accelerator and shifts the engine to the drive or reverse range while pressing the accelerator, the car will suddenly start, which is very dangerous.

According to the inventor's study, it is presumed that the erroneous operation as described in B occurs due to the following reasons.

2: In a manual transmission car, it is necessary to press the clutch pedal to shift to L speed, which determines the position of the driver's foot.However, in an A/T car, the driver must press the pedals to shift. There is no need to do so, and as a result, the gear change operation may be performed without the foot position being determined correctly, resulting in the above-mentioned erroneous operation.

In view of the above two points, an object of the present invention is to prevent erroneous starting of an A/T vehicle due to erroneous pedal depression.

(Means for Solving the Problems) Therefore, in order to achieve the above object, the present invention provides shift request position detection means for outputting a signal for detecting a shift request position selected by an occupant, as shown in FIG. 100, a stop state detection means 200 that outputs a signal to detect whether the vehicle is in a stopped state, a brake detection means 300 that outputs a signal to detect whether the brakes of the vehicle are being operated, and each of the detection means 100, 200 and 300, a signal indicating that the vehicle is stopped is input from the stop state detection means 200, and the shift request position detection means 1
When a signal indicating a shift position for driving from 00 is input, a shift change signal corresponding to the shift position for driving of the vehicle is output to the automatic transmission 500 only when a signal indicating that the brake is being operated is input. A technical means is adopted in which a control means 400 is provided.

(Function) By adopting the above technical means, after starting the engine, when operating the shift selection means, a request is issued to change to a range for vehicle driving other than parking range P or neutral range N. For example, if the foot brake is depressed, the automatic transmission 5 will perform a shift change, but if it is not depressed, the automatic transmission 5 will not shift. As a result, if you mistakenly press the accelerator for the brake, or forget to press the brake, the gear will not shift.

(Effects of the Invention) Therefore, according to the present invention, it is possible to reliably prevent a sudden start due to a driver's erroneous operation, and improve the safety of an A/T vehicle.
This has the effect of making it possible to

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 2 shows a configuration diagram of a control device for an automatic transmission for automobiles. Reference numeral 1 denotes an automatic transmission, in which a known hydraulic control section 2 for controlling a planetary gear unit, etc. is built-in, and this hydraulic control section 2
A control shaft 3 for driving is connected to a control valve (valve activated by shift switch operation) provided in the control shaft 3, for example 6.
Parking P, rear R5 neutral N, with 0 degree rotation.
Drive D, second 2. Valve operation is performed according to six types of shift positions, including low L. Reference numeral 6 denotes a DC motor that rotationally drives the control shaft 3, and its rotating shaft is connected to the control shaft 3 via a reduction gear 7.

A rotational position sensor 8 is provided within the reducer 7 to detect the rotational position of the control shaft 3 (the rotational position corresponding to the shift position PL) and output a detection signal indicating the position.

Reference numeral 9 denotes a push-operated shift switch provided in the driver's seat of the automobile, and this shift switch 9 has six shift positions (as an example of shift request position detection means).
P, R, N, D, 2. A shift operation detector 1o is installed to detect L). Reference numeral 11 denotes a vehicle speed sensor that detects the vehicle speed of an automobile, which is an example of means for issuing a stop notice 84tt.

Reference numeral 12 is a foot brake sensor, which outputs a signal indicating that the brake is being operated when the foot brake is depressed, as an example of a brake detection means, and a foot brake sensor of type J and i that opens and closes in response to depression of the foot brake. Use a switch etc.

20 is a control means for controlling the automatic change machine 1 according to the operating state, and is mainly composed of a microcomputer. 21
C that executes various arithmetic and control processes based on
PtJ, 22 is a read-only memory ROM for storing program data and various constants, 23 is a readable and writable temporary memory RAM, and 24 is an input/output circuit. A rotational position sensor 8, a shift operation detector 10, a heavy speed sensor II, a foot brake sensor 12, etc. are connected to the input/output circuit 24, and the detection signal numbers input from each sensor group are sent from here to the CPU 21. Further, the input/output circuit 24 is connected so that a control signal for controlling the hydraulic motor 6 is outputted to a motor control circuit 25 . As shown in FIG. 3, the motor control circuit 25 is configured by connecting 1.4 diodes D1 to D4 and four transistors Trl to Tr4 in a bridge manner, and includes transistors Tr2 and Tr3.
When a control signal to turn on is applied to each base terminal, power for forward rotation is supplied from power supply B to the DC motor 6,
Further, when a control signal to turn on the transistors Tri and Tr4 is applied to each base terminal, a reverse current is supplied to the DC motor 6, and furthermore, the transistors Tri and Tr4 are supplied with a reverse current.
3 or when a control signal to turn on Tr2 and Tr4 is applied to each base terminal, the terminals of the DC motor 6 are short-circuited, and if the motor 6 is rotating in either direction, it operates to apply dynamic braking. do.

Next, the operation of the control device will be explained with reference to a flowchart (FIG. 4) of the control processing executed by the CPU 21.

When entering this routine, first, step 110 is executed, and it is determined whether or not the shift switch 9 has been changed.
It is judged based on the detection signal from the lateral position 10, and if there is a switching operation of the shift switch 9, then the process proceeds to step 120, and if there is no switching operation of the shift switch, this routine is exited. In step 120, it is determined whether or not the shift condition is satisfied. For example, if a switching operation is performed to the reverse R shift position, the vehicle speed signal from the vehicle speed sensor 11 indicates that the vehicle speed is approximately zero. If the shift condition is met, then step 130 is executed, and if there is a forward vehicle speed, the shift condition is deemed not met and the routine ends. Also, if there is no separate dangerous operation such as downshifting or upshifting when the forward vehicle speed is present, this step is skipped and the process proceeds to the next step 130. In step 130, it is determined whether the car is stopped based on the signal from the vehicle speed sensor 11, and if the car is running, step 1
The process moves to step 60, and if the vehicle is stopped, the process moves to step 140. In step 140, it is determined whether the shift position selected by the shift switch 9 is N or P. If it is N or P, the process moves to step 160, and otherwise, the process moves to step 150.

In step 150, a brake operation is detected based on a signal from the foot brake sensor 12, and if the brake is not depressed, this routine is exited.

Therefore, by using the shift switch 9, the range T), 2
．． Even if either L is selected, if the foot brake is not pressed while the vehicle is stopped before starting, a command to shift to the selected shift position will not be issued, ensuring that sudden starts are prevented. .

If the foot brake is connected in step 150, the process proceeds to step 160, where a signal for shifting to the shift position selected by the shift switch 9 is output.

At this time, the CPU 21 determines whether the shift direction is forward or reverse, and outputs a control signal to the motor control circuit 25 accordingly. For example, from parking P through neutral N etc.
), that is, in the forward direction, transistors Tr2 and Tr3 of the motor control circuit 25 are turned on, a current for forward rotation is supplied to the DC motor 6 from the power supply B, and the DC motor 6 rotates in the forward direction. . When the rotation of the control shaft 3 passes through the maximum torque point due to the positive rotation of the DC motor 6 and enters the region of the drive D that is the target shift position, if dynamic braking is applied to the DC motor 6, a negative torque (braking force) is immediately generated. ) is generated in proportion to the rotational speed of the motor 6, and the control shaft 3 is stopped at a predetermined stable stop position. Specifically, based on the control shaft detection signal sent from the rotational position sensor 8, it is determined whether the rotational positions of the controller 1 to the roll shaft 3 have entered the drive D area, which is the target shift position, that is, the braking area. When entering the braking section of the IS live region, a braking signal is sent to the motor control circuit 25 to instruct the DC motor 6 to perform dynamic braking. That is, in the motor control circuit 25, when the transistors 1'r1 and Tr3 or Tr2 and 'r4 are turned on, both terminals of the DC motor 6 are short-circuited, and dynamic braking is applied.

If it is determined that the shift direction is the opposite direction (for example, from neutral N to hack R), then the DC motor 6 is driven in the reverse direction. This reverse drive is performed by turning on transistors Tri and Tr4 of the motor control circuit 25, thereby causing the control shaft 31 to rotate in the opposite direction (from neutral direction to hack R direction). And control shaft 3 in -1- mark and In.
When the rotation of the motor passes through the maximum torque point (point B) and enters the braking section of the R region of the target shift 1 position, dynamic braking is applied to the DC motor 6 and the control shirt l-3
Stop at the hack R position. Even in this case,
As with the above-described forward rotation, the control shaft 3 can be stopped at a desired shift position without requiring strict control over the timing of dynamic braking.

The present invention is not limited to the above-described embodiments, but can be similarly applied to, for example, hydraulically controlled A/T vehicles that are not controlled by a microcomputer. In other words, in an A/T vehicle in which a shift lever is provided with a knob for fixing the shift position, and the shift lever is configured to shift freely when the knob is pressed, an electromagnetic solenoid that regulates the movement of the knob is installed. If the vehicle is stopped and the foot brake is pressed, current may flow through the solenoid to release the restriction on the operation of the knob.

In addition to the configuration of the above-described embodiment, in order to ensure that the driver is informed that the brake is not pressed during the start operation, a warning light is turned on and a voice alarm (V, etc.) is provided. In addition, the method for preventing erroneous start 1 as described above may be limited to only the first start after the engine is started, and after the driver gets out of the vehicle while the engine is running and then re-enters the vehicle. This is because at this time, the relative positions of the driver and the vehicle pedals are misaligned, and there is a high probability that the driver will mistakenly press the accelerator instead of the brake.

To limit in this way, proceed as follows.

A signal from the footbrake detection means is input, and once this signal is detected after the engine is started, it is set as a footbrake signal -0N and is held until the ignition switch is turned off or the signal is particularly reset. This may be realized by using a flip-flop in an electric circuit, or by using an I/O function that temporarily stores data when the foot brake signal is first detected in the microcomputer program. This may be realized by setting a flag during AM and referring to this flag thereafter. This flag is cleared in the initialization routine at the beginning of the program.

If a means for detecting the driver's absence from the seat is provided using a seat pressure sensor or the like, the above-mentioned flip-flop or flag is cleared when the driver's absence from the seat is detected. This occurs not only immediately after starting the engine, but also during engine operation.
It also prevents erroneous operation when starting the vehicle after the driver leaves the seat and re-enters the vehicle.

[Brief explanation of drawings]

FIG. 1 is a basic configuration diagram of the present invention, FIG. 2 is an overall configuration diagram of an embodiment of the present invention, FIG. 3 is a motor control circuit diagram, and FIG. 4 is a flowchart showing control processing. DESCRIPTION OF SYMBOLS 1... Automatic transmission, 2... Hydraulic control part 2 10... Shift operation detector, 20... Control means. 6...Motor.

Claims (1)

[Scope of Claims] Shift request position detection means for outputting a signal for detecting a shift request position selected by an occupant; stop state detection means for outputting a signal for detecting whether the vehicle is in a stopped state; and a vehicle brake. a brake detection means that outputs a signal for detecting whether or not the vehicle is being operated; signals from each of the detection means are input; a signal indicating that the vehicle is stopped is input from the stop state detection means; and When a signal indicating a driving shift position is input from the shift request position detection means, a shift change signal corresponding to the driving shift position of the vehicle is output only when a signal indicating that the brake is being operated is input. 1. A control device for an automatic transmission, comprising a control means for controlling an automatic transmission.