JPS60176829A - Control device for automatic speed change gear - Google Patents

Abstract

PURPOSE:To miniaturize an actuator, by providing such an arrangement that the rotational position of a control shaft for driving and controlling the hydraulic control section of an automatic speed change gear is accurately and simply controlled by a motor in accordance with the control operation of a shift switch. CONSTITUTION:A control shaft 3 is rotatingly driven by a motor 6 in accordance with the change-over operation of a shift switch 9, and is controlled to stop at a predetermined position. When the control shaft 3 reaches a stable stationary position area which are provided by a cam 4 coupled to the control shaft 3 and a pressing member 5, the motor 6 is subjected to braking due to electrical generation. With this arrangement it is not necessary to precisely detect and control the timing of braking, and the control shaft 3 may be stopped at an accurate position in accordance with the control operation of the shift switch 9 so that the control process may be simplified. Further, no conventionally used clutch is required, thereby the actuator may be miniaturized.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a control device for an automatic transmission of an automobile, and in particular to control of a motor that rotationally drives a control shaft that drives and controls a control valve of a hydraulic control section of an automatic transmission. Regarding equipment.

Conventionally, in automatic transmissions for automobiles, shift 1 to levers are connected to connecting members such as links, rods, or cables, and are connected to a control shaft (which drives and controls the control valve of the hydraulic control section) provided in the automatic transmission body. The hydraulic control unit is controlled by directly operating the control shaft, that is, the control valve, by the force of the driver operating the shift lever.

On the other hand, in recent years, in order to improve the operability of shift operations and to perform shift operations quickly and reliably, switches have been used instead of shift levers, and the control shaft of the automatic transmission body is controlled by a motor that operates in response to the switch operation. A control unit for an automatic transmission has been developed.

However, the automatic transmission control device driven by the motor of this scale is configured to rotate the control shirt 1 of the automatic transmission main body by a predetermined angle by using the driving force of the motor via an electromagnetic clutch and a reduction gear. An electromagnetic clutch is required to reliably stop the control shaft at a predetermined angular position corresponding to the shift operation. Therefore, since the use of this electromagnetic clutch increases the size of the actuator structure centered on the motor, the angle corresponding to the shift operation of the roll shaft to control 1 using the deceleration Im and the motor without using the electromagnetic clutch Attempts were made to rotate the motor to a certain position and stop it, but due to the fact that the movement of the roll shaft is restricted by a cam and the inertia of the drive system, it is not possible to accurately rotate the motor to the correct angular position simply by cutting off the motor current. In addition, control for applying reverse braking by flowing a reverse current at the time of stopping requires accurate control of the reverse braking time depending on the shift position, complicating the control.

-3- [Object of the Invention] The present invention has been made in view of the above points, and it is possible to accurately control the rotational position of a control shaft that drives and controls the hydraulic control section of an automatic transmission by a motor in accordance with the operation of a shift switch. It is an object of the present invention to provide a control device for an automatic transmission that can be easily controlled, does not use an electromagnetic clutch in the drive system, and can downsize the actuator.

[Structure of the Invention] In order to achieve the above object, the present invention provides, as shown in FIG. is driven to a predetermined rotational position by the motor 6A according to the
A control device for an automatic transmission in which an engaging member 4Δ for creating a stable stationary state at each shift position is connected to the control shaft 3A, comprising: a shift operation detector 10A for detecting an operating state of the shift switch 9A; -4 - A rotational position sensor 8Δ detects the rotational position of the control shaft 3A, and when the controller 1 to the roll shaft 3Δ reach the braking zone of the target shaft position due to the rotational drive of the motor 6A, it applies dynamic braking to the motor 6A. Calculation control means 20△
The gist of the invention is a control device for an automatic transmission characterized by the following.

[Example] Hereinafter, embodiments of the present invention will be described 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 (a valve activated by shift switch operation) provided in
At 0 degrees of rotation, valve operation is performed according to six types of shift positions: P, R, N, D, 2, and L. control-5
- A cam plate 4 having recesses 4a that smoothly change according to the positions of the six shifts 1 is pivotally attached to the shaft 3 as an engagement member, and the four parts 4a of the cam plate 4 have leaf springs 5a. A suppressing member 5 that pivotally supports a cam roller 5b at its tip is attached to a cam plate 4.
In other words, the cam roller 5b is pressed against the recess 4a in order to create a rotational load (reaction force against torque) for making the controller 1 to roll shaft 1 to 3 stably stationary at each shift position (P to L). Ru. 6 is a DC motor that rotationally drives the control shaft 3, and its rotating shaft is connected to the reducer 7.
It is connected to the control shaft 3 via.

A rotational position sensor 8 is provided within the reducer 7 to detect the rotational position of the control shaft 3 (rotational position corresponding to shift positions P to L) and output a detection signal indicating the position. 9 is a push-operated shift switch provided in the driver's seat of a car, and this shift switch 9 has six shift positions (P, , R1N1D12.1-).
A shift operation detector 10 is installed to detect the shift operation. 11 is a vehicle speed sensor that detects the vehicle speed of the automobile.

-6- 20 is an arithmetic control process that controls the automatic transmission 1 according to the operating state, and is mainly composed of a microcomputer.

21 is a CPU that executes various arithmetic and control processes based on programs; 22 is a read-only memory ROM that stores program data and various constants; 23 is a readable and writable temporary memory RAM; 2/I is an input/output circuit It is. A rotation position range 8, a shift operation detector 10, a vehicle speed sensor IF 11, etc. are connected to the input/output circuit 24, and the detection signals input from each sensor are sent to the CPU 2 from here.
1, and further from the input/output circuit 24 to the DC motor 6.
The motor control circuit 25 is connected so that a control signal for controlling the motor is outputted to the motor control circuit 25. As shown in FIG. 3, the control circuit 25 is configured by connecting four diodes D1 to D4 and four transistors Tr1 to Tr7I in a bridge manner, and turns on transistors Tr2 and Tr3. When the control signal is applied to each base terminal, a current for forward rotation is supplied from the power supply B to the DC motor 6, and the transistor T
A control signal that turns on r1 and Tr4 is sent to each base terminal -
7 - When applied, a reverse current is supplied to the DC motor 6, and the transistors Tri and Tr3 or Tr2
When a control signal that turns on 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.

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

When this routine is entered, first, step 110 is executed, and it is determined whether or not there has been a switching operation of the switch 9 to shift 1 based on the detection signal from shift I to position lateral position 10, and if there has been a switching operation of the shift switch 9. If so, the routine proceeds to step 120, and this routine can be carried out if there is no changeover operation of the shift switch. In step 120, it is determined whether or not the Schiff I-condition is satisfied, and for example,
When the switching operation is performed to the shift 1 to position of back R, if the vehicle speed is almost zero according to the vehicle speed signal from the vehicle speed sensor 11, it is assumed that the shift condition is satisfied and the next step is shift 8.
- Execute step 130, and if there is a forward vehicle speed, the shift condition is deemed unsatisfied and this 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, the direction of the shift switch changeover operation is determined, and for example, from parking P to new 1 to
If a switching operation is performed in the direction of D-(L), that is, in the positive direction, through the motor control circuit N, etc., the process proceeds to step 140, and a control signal for normal rotation of the DC motor 6 is sent to the motor control circuit 2.
As a result, the transistors Tr2 and Tr3 of the motor control circuit 25 are turned on, and a current for normal rotation is supplied to the DC motor 6 from the power supply B, so that the DC motor 6 rotates in the normal direction. Figure 5 shows the torque curves of the control shirts 1 to 3 when the DC motor 6 rotates in the forward direction, and the potential energy curve of the control shaft 3 obtained by integrating the torque, that is, the torsion moment, over the rotation distance. . From these two curves, it can be seen that the control shaft 3 is rotated in the -9- positive direction by the forward rotation of the DC motor 6, and from a certain shift position (e.g., neutral N) to the next positive shift position (e.g., drive D). When a shift is performed, due to the rotational reaction force generated by the action of the cam plate 4 and the suppressing member 5, from the neutral N region to the point A (maximum torque point) which enters the drive D region, control shirts I to 3 are shifted. It can be seen that the torque increases rapidly, and as the drive passes point A and enters the drive D region, the torque decreases rapidly. Therefore, when the rotation of the control shaft 3 passes through the maximum torque point and enters the region 1 of the drive D, which is the target shift position, if dynamic braking is applied to the DC motor 6, a negative torque (braking force) is immediately applied to the motor. This occurs in proportion to the rotational speed of the control shaft 3, and the control shaft 3 can be stopped at a predetermined stable stationary position.

For this reason, in step 160, based on the rotational position detection signal of the controller 1 to the roll shaft 3 sent from the rotational position sensor 8, the rotational position of the control shirt h3 is determined in the area of the drive D where the target shift position is the braking position. -10- It is determined whether or not the motor has entered the section, and if it has passed point A and entered the braking section of the drive region, then step 170 is executed, and a braking signal is sent to the motor control circuit 25 to control the DC motor 6. Apply dynamic braking to. That is, in the motor control circuit 25, the transistor Tr
When 1 and Te3 or Te3 and Te4 are turned on, both terminals of the DC motor 6 are short-circuited, and dynamic braking is applied.

In this dynamic braking, the braking force is generated according to the magnitude of the induced electromotive force generated in the motor, so the faster the motor rotation speed is, the greater the braking force is applied, and as the speed decreases, the braking force decreases. In addition, even when dynamic braking is applied at any position within the braking range of the target shift position, accurate rotation corresponding to the predetermined shift position is achieved due to the stable position and static action of the rotational reaction force by the cam plate 4 and the pressing member 5. The control shaft 3 can be stopped at this position. Furthermore, since the braking force of the dynamic braking disappears when the DC motor 6 stops, there is no need to control the timing of turning off the braking signal, and after the dynamic braking is applied for a certain period of time in step 170, this control processing routine is terminated -11- Zuru.

If it is determined in step 130 that the shift direction is the opposite direction (for example, from neutral N to back R), then the process proceeds to step 150, where the DC motor 6 is driven in the reverse direction. This reverse drive is performed by turning on the 1-transistors Tri and Te4 of the motor control circuit 25, whereby the control shirt 1-3 is rotated in the opposite direction (from courtral N to back R), and its torque curve The rotational reaction force curve appears as shown in FIG. Step 160 is executed in the same manner as above, and when the rotation of the control shaft 3 passes through the maximum torque point (point 8) and enters the braking area of the back R region of the target shift position, step 170 is executed. Then, dynamic braking is applied to the DC motor 6 to stop the control shaft 3 at the back R position. In this case as well, the control shaft 3 can be stopped at a desired shift position without requiring strict control over the timing of the dynamic braking, as in the above-described forward rotation.

-12= [Effects of the Invention] As explained above, according to the automatic transmission control device of the present invention, the motor rotates the recon 1 to the roll shift V71 in response to the switching operation of the shift 1 to the switch. When controlling the motor to stop at a predetermined position, when the control shaft reaches a region where a stable resting position is created between the cam connected to the control shaft and the pressing member, dynamic braking is applied to the motor to stop it. Since the configuration is configured to control the timing of braking, there is no need to strictly detect or control the timing of braking (also, without controlling the braking time, it is possible to move the control shaft 71 to the exact shift position according to the shift switch operation). It is possible to stop the motor, and the control process can be simplified.Furthermore, the electromagnetic clutch used conventionally is no longer necessary, and the actuator, mainly the motor, can be downsized.

[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. The figure and FIG. 6 are torque curves and rotational reaction force curves when the control shaft rotates in the normal and reverse directions. 1... Automatic speed change* 2... Hydraulic control unit 3... Control shaft 4... Cam plate 5... Pressing member 6... DC motor 8... Rotational position sensor 9...
Shift lever 1o...Shift position detector 20...Arithmetic control means Agent Patent attorney Tsutomu Sadatsu and 1 other person-14- Figure 3 Figure 4 Daily QK-8

Claims (1)

[Scope of Claims] A control shaft that drives and controls the hydraulic control section of an automatic transmission for an automobile is driven to a predetermined rotational position by a motor in response to shift switch operation, and the control shaft is in a stable stationary state at each shift position. A control device for an automatic transmission connected to an engaging member that creates a shift switch includes: a shift operation detector that detects the operating state of the shift 1 switch; a rotational position sensor that detects the rotational position of the control shirt I; A control device for an automatic transmission, comprising: arithmetic control means for applying dynamic braking to the motor when the control shaft reaches a braking zone at a target shaft position due to the rotational drive of the motor. -1-