JP2943505B2 - Device for preventing erroneous operation of control mechanism for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing an erroneous operation of a control mechanism for an automatic transmission in which switching of each shift range including a parking range in an automatic transmission is realized by electric control.

[0002]

2. Description of the Related Art In an automatic transmission, a shift range such as a drive range or a reverse range for traveling or a parking range or a neutral range is switched by switching a range switching valve (manual valve). The range switching valve is generally switched by manual operation, but a configuration in which the switching is performed by electrical control has already been proposed.

For example, Japanese Utility Model Laid-Open Publication No. Sho 61-82159 discloses a configuration in which an actuator for switching a shift range of an automatic transmission is drive-controlled based on a range instruction signal by a switching operation of a select switch. In this publication, when the automatic transmission is shifted to the reverse range and moving backward, when the vehicle speed is equal to or higher than a predetermined value, the changeover operation of the select switch is canceled (only the changeover operation to the neutral range is permitted) and a warning signal is issued. Is output, and when the vehicle speed is equal to or lower than a predetermined value, the shift range can be switched by switching the select switch.

[0004]

In the technique disclosed in the above publication, when the vehicle speed is equal to or lower than a predetermined value, it is possible to switch to the parking range by operating a select switch. When the selector switch is accidentally operated to the parking range, if the driver switches to the parking range without warning the driver to switch to the parking range, the driver will be unexpectedly shocked. Therefore, if the select switch is operated to the parking range when the vehicle speed is equal to or lower than the predetermined value, the driver is warned to switch to the parking range and then switched to the parking range, so that an unexpected shock received by the driver can be avoided. There are ways to prevent this.

[0005] However, when the driver intentionally operates the select switch to the parking range, the driver is warned to switch to the parking range and then switches to the parking range. The time to switch becomes longer,
It may not be possible to stop at any position.

A technical object of the present invention is to provide a warning signal for switching to the parking range only at a vehicle speed at which switching to the parking range without outputting a warning signal for switching to the parking range causes an unexpected shock to the driver. The above-mentioned problem is solved by switching to the parking range after outputting the signal.

[0007]

In order to solve the above-mentioned problems, an erroneous operation prevention device for a control mechanism for an automatic transmission according to the present invention is configured as follows.

That is, an automatic transmission is provided by an actuator for driving a range switching valve of the automatic transmission and a range control unit for outputting a drive signal for driving and controlling the actuator based on a range instruction signal by switching operation of a select switch. A control mechanism for an automatic transmission that performs switching of a shift range including a parking range, comprising a vehicle speed sensor that detects a vehicle speed and outputs a vehicle speed signal to the range control unit, wherein the range control unit includes the range instruction signal and the range instruction signal. When the vehicle speed is equal to or more than a first predetermined value and an instruction signal for the parking range is input based on the vehicle speed signal, switching to the parking range is prohibited, and a second predetermined value at which the vehicle speed is lower than the first predetermined value In the following, when the parking range instruction signal is input, the switching to the parking range is performed. When a vehicle speed is equal to or less than the first predetermined value and equal to or greater than the second predetermined value and a parking range instruction signal is input, a warning signal is output and then switching to the parking range is permitted. It is configured as follows.

[0009]

In this configuration, when the vehicle is traveling at a vehicle speed equal to or higher than the first predetermined value and the switching signal of the selection switch is input to the range control unit by the switching operation of the select switch, the switching to the parking range is inhibited. ,
When the vehicle speed is equal to or lower than a second predetermined value lower than the first predetermined value and a parking range instruction signal is input to the range control unit, switching to the parking range is permitted. Here, when the vehicle speed is equal to or lower than the first predetermined value and equal to or higher than the second predetermined value, and a parking range instruction signal is input to the range control unit, a switch to the parking range is permitted after outputting a warning signal. The driver can prepare for an unexpected shock when the vehicle is switched to the parking range.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a perspective view showing a part of the front of the driver's seat of the vehicle. A shift lever 10 is disposed on the left side of the steering column portion 14 near the steering wheel 12, and by operating the shift lever 10, a select switch SW for selecting a shift range of the automatic transmission AT described later is switched. The select switch SW may be a push-type switch that is directly operated by the driver. An instrument panel 16 on the front of the driver's seat is provided with a range indicator 25 for displaying the shift range of the automatic transmission AT, and as shown in FIG. 4A, a position corresponding to the current shift range of the automatic transmission AT is displayed. Lights up on a green background.

FIG. 3 is a perspective view showing an outline of a range switching valve 30 for switching a shift range of the automatic transmission and a control system thereof. The range switching valve 30 is a spool valve type, and is supplied with a line hydraulic pressure, which is a basic hydraulic pressure for controlling the automatic transmission. By operating the spool 30a of the range switching valve 30 in the axial direction,
The discharge port is switched to control engagement and release of a friction engagement device (not shown) for setting each shift range.

A worm wheel 33 is fixed on the control shaft 32. This worm wheel 3
A worm 54 formed on a drive shaft 52 of an actuator (DC motor) 50 for switching the range switching valve 30 meshes with the worm wheel 3. Therefore, the rotational driving force of the actuator 50 is transmitted to the control shaft 32 at a reduced speed due to the engagement between the worm 54 and the worm wheel 33.

The rotation of the control shaft 32 moves the spool 30a of the range switching valve 30 in the axial direction thereof through the rotation of a detent lever 36 fixed on the shaft. In the vicinity of the worm wheel 33, the rotational position of the worm wheel 33, that is, the range switching valve 3
A valve position sensor 22 such as a variable resistor that can detect a 0 switching position is provided.

The detent lever 36 has a fan shape, and a plurality of uneven portions 36a are formed on the outer periphery thereof. A roller 38a provided at an end of the detent spring 38 is engaged with one of the concave and convex portions 36a. Thus, a detent mechanism 34 for determining the rotational position of the control shaft 32, that is, the plurality of range switching positions of the range switching valve 30 is configured.

FIG. 5 shows a parking lock mechanism 41. The parking rod 43 connected to the detent lever 36 passes through the parking cam 40 so as to be relatively movable. An engaging portion 43a is formed on the parking rod 43, and a spring 45 is interposed between the engaging portion 43a and the parking cam 40. Shift lever 1
When 0 is operated to the parking (P) range position, the range switching valve 30 is driven by driving the actuator 50.
Is switched to the position of the P range, and the parking rod 43 moves rightward in FIG. 4 in conjunction with the rotation of the detent lever 36 at this time. At this time, the parking cam 40 also moves rightward due to the spring force of the spring 45 and gets over the parking bracket 46 and is pushed up to the position shown by the dotted line in FIG. By the action of the parking cam 40, the parking claw 42 meshes with the parking gear 44 fixed to the output shaft of the automatic transmission AT, and the output shaft system of the vehicle is locked.

FIG. 1A shows an electric control system for controlling the rotational drive of the actuator 50.
A range control unit (SBW control unit) 20 is a read only memory (ROM) in which a microcomputer is used and stores programs necessary for various software processes for switching the shift range of the automatic transmission. An arithmetic processing unit (CPU) and a writable memory (RA) for temporarily storing variables necessary for a program.
M) and the like.

The range control unit 20 has a range instruction signal output by a switching operation of the select switch SW,
Valve position sensor 22 and vehicle speed sensor 2 for detecting vehicle speed
4 are input together. Further, from the range control unit 20, a drive signal for a drive circuit (not shown) of the actuator 50, the range indicator 25, and the voice navigation control unit 2
6 are output. Further, the voice navigation control unit 26 has a function of outputting a sound from the speaker 27 to warn the driver when the select switch SW is erroneously operated.

FIG. 1B shows a condition for switching to the P range by the range control unit 20. When the vehicle speed V is equal to or higher than V1 (first predetermined value) (V ≧ V1), switching to the P range is prohibited, and when the vehicle speed V is equal to or lower than predetermined value V0 (second predetermined value) (V ≦ V0). At some point, switching to the P range is permitted. When the vehicle speed V is in the region between V0 and V1 (V0 <V <V1), switching to the P range is permitted immediately after warning the driver.

Next, the operation of the embodiment constructed as described above will be described. When the select switch SW is switched by the operation of the shift lever 10, the drive of the actuator 50 is controlled based on the drive signal output from the range control unit 20 in accordance with the range instruction signal at that time, whereby the range switching valve 30 is switched. Automatic transmission A
A shift range of T is selected. When the parking range is selected, the parking rod mechanism 41 is simultaneously operated to lock the output shaft of the automatic transmission AT. Further, the position corresponding to the current shift range of the automatic transmission AT is lit on the range indicator 25 with a green background color.

Here, for example, during traveling in the drive (D) range, the shift lever 10 is operated to the P range position when the vehicle speed V is equal to or higher than the predetermined value V1, and the select switch SW
Is input to the range control unit 20, the range control unit 20 does not output a drive signal to the drive circuit of the actuator 50, and warns the range indicator 25 and the voice navigation control unit 26. Outputs each signal. The warning signal is shown in FIG.
In the range indicator 25, the background color of “P” indicating the current shift position of the shift lever 10 is changed to, for example, normal green and a red lighting display, as shown in FIG.
"D" is used to indicate the current position of the range switching valve 30.
The background color of is blinking green. On the other hand, the voice navigation control unit 26 warns the driver to return the shift lever 10 to the position of the D range by the sound from the speaker 27.

Conversely, when the vehicle is running in the D range, the vehicle speed
When the shift lever 10 is operated to the P range position at 0 or less, and the P range instruction signal is input from the select switch SW to the range control unit 20, the range control unit 20 sends a drive signal to the drive circuit of the actuator 50 as usual. Is output to switch to the P range. Here, the predetermined value V0
Is set to the maximum speed that will not cause an unexpected shock to the driver even if the output shaft of the automatic transmission AT is locked by switching to the P range without outputting a warning signal to the driver. There is no problem if the warning signal is not output when switching.

When the shift lever 10 is operated to the P range position when the vehicle speed V is equal to or lower than the predetermined value V1 and equal to or higher than V0 while the vehicle is traveling in the D range, and a P range instruction signal is input to the range control unit 20 from the select switch SW. Similarly, when the vehicle speed V is equal to or higher than the predetermined value V1, the range control unit 20 outputs a warning signal to the range indicator 25 and the voice navigation control unit 26 without outputting a drive signal to the drive circuit of the actuator 50. I do. Here, in the voice navigation control unit 26, the warning signal warns the driver to return the shift lever 10 to the position of the D range by the sound from the speaker 27, and the warning signal must be returned to the D range even after a predetermined time has elapsed. Warning to switch to P range, range indicator 25
4B, the background color of “P” indicating the current shift position of the shift lever 10 is illuminated in red as shown in FIG. 4B, and “D” is displayed to indicate the current position of the range switching valve 30. As shown in FIG. 4C, when the background color is displayed in green blinking and the voice navigation control unit 26 warns not to return to the D range even after a predetermined time has elapsed and to switch to the P range, as shown in FIG. Is switched from the red lighting display to the yellow lighting display and then switched to the P range.

As described above, in the present embodiment, if the vehicle is switched to the P range without outputting a warning signal, the vehicle is switched to the P range immediately after outputting the warning signal at a vehicle speed at which the driver receives an unexpected shock. , P range can be prepared for an unexpected shock.

Although the embodiments of the present invention have been described in detail above, it is needless to say that the present invention is not limited to such specific examples, and various modifications are possible within the scope of the claims. Are included.

For example, in this embodiment, when the shift lever 10 is operated to the P range position when the vehicle speed V is equal to or lower than the predetermined value V1 and equal to or higher than V0 while driving in the D range,
Although the configuration is such that the warning signal is output in the D range, the neutral (N) range is switched during the warning signal output, and the driving force from the engine may be cut off.

In FIG. 5, when the parking cam 40 moves from the dotted line position to the solid line position,
When switching from one range to another range, the parking cam 40 bites into the parking claw 42, which may increase the frictional resistance between the parking cam 40 and the parking claw 42.
Also have to be bigger. Accordingly, in designing the actuator 50 for moving the parking rod 43 shown in FIG. 3, the maximum power of the actuator 50 is set to a power enough to exert the pulling force of the parking rod 43 to overcome the maximum frictional resistance at the time of biting. , And the shape of the actuator 50 becomes large accordingly, which is disadvantageous in terms of mounting space. However, the present invention can solve this problem as described below. That is, the pulling force Fa of the parking rod 43 is equal to the force Fb that the parking cam 40 receives from the parking claw 42 and the parking cam 4
It is determined by the friction coefficient μ of the contact surface between 0 and the parking claw 42 and the taper angle α of the parking cam 40, and is expressed by the following equation: Fa = 2Fb (μ−tanα). Fa also increases.

Therefore, as can be seen from the above equation, if the taper angle α is increased, the pulling force Fa becomes smaller, so that the taper angle α
Is increased, the pullout force Fa is reduced, and the maximum power of the actuator 50 can be set small.

Here, when the taper angle α is increased, the parking cam 40 is easily pulled out naturally.
5, the spring force must be increased. However, when the spring force increases, the speed at which the parking cam 40 moves to the right, that is, the speed at which the parking claw 42 bites into the parking gear 44 (ratcheting speed) increases, and the rotation speed of the parking gear 44 increases accordingly. However, even if the vehicle speed V is high, the parking claw 42 bites into the parking gear 44 and the drive system of the vehicle is locked. However, in the present invention, when the vehicle speed V is equal to or higher than a predetermined value,
Since the control for prohibiting the switching to the range is performed, there is no problem since the drive system of the vehicle is not locked at a high vehicle speed.

If the parking claw 42 cannot bite into the parking gear 44 when the vehicle speed V is 3 km or more, for example, because the taper angle α is small and the ratcheting speed is small, in FIG. Is set to 4 km and the control is not allowed to be switched to the P range until the vehicle speed V becomes 3 km even if the control for unconditionally permitting the switching to the P range is performed below 4 km. However, as described above, when the taper angle α is large and the ratcheting speed is increased, switching to the P range is performed when the vehicle speed V becomes 4 km or less. That is, by increasing the ratcheting speed, switching to the P range can be performed even at a higher vehicle speed.

[0031]

As described above, according to the present invention, when the vehicle speed is equal to or higher than the first predetermined value and a parking range instruction signal is input, switching to the parking range is prohibited, and the vehicle speed is reduced to the first speed.
When a parking range instruction signal is input at a value equal to or less than a second predetermined value lower than a predetermined value, switching to the parking range is permitted, and when the vehicle speed is equal to or less than the first predetermined value and equal to or more than the second predetermined value, the parking range is set. Since the switch to the parking range is permitted after the warning signal is output when the instruction signal is input, it is possible to prepare for an unexpected shock accompanying the switch to the parking range which occurs even at a low speed. it can.

[Brief description of the drawings]

FIG. 1 is an electric control system diagram for switching a shift range of an automatic transmission.

FIG. 2 is a perspective view showing a part in front of a driver's seat of the vehicle.

FIG. 3 is a perspective view showing an outline of a range switching valve and a control system thereof.

FIG. 4 is a diagram illustrating the operation of a range indicator.

FIG. 5 is a diagram showing a parking lock mechanism.

[Explanation of symbols]

 Reference Signs List 20 range control unit 22 valve position sensor 24 vehicle speed sensor 30 range switching valve 50 actuator SW select switch AT automatic transmission

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-255263 (JP, A) JP-A-1-101233 (JP, A) JP-A-64-9030 (JP, A) 42961 (JP, U) Japanese Utility Model Showa 62-169819 (JP, U) Japanese Utility Model Showa 61-82159 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 59/00-61 / 12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (1)

(57) [Claims] 1. An automatic transmission comprising: an actuator for driving a range switching valve of an automatic transmission; and a range control unit for outputting a drive signal for driving and controlling the actuator based on a range instruction signal by a select switch switching operation. A control mechanism for an automatic transmission that performs shift range switching including a parking range, comprising a vehicle speed sensor that detects a vehicle speed and outputs a vehicle speed signal to the range control unit, wherein the range control unit includes the range instruction signal and When the vehicle speed is equal to or higher than a first predetermined value and an instruction signal for the parking range is input based on the vehicle speed signal, switching to the parking range is prohibited, and a second predetermined speed whose vehicle speed is lower than the first predetermined value is inhibited. When the parking range instruction signal is input below the value, switching to the parking range is performed. And yes, the vehicle speed is first
When the parking range instruction signal is input at a value equal to or less than a predetermined value and equal to or more than the second predetermined value, a switch to the parking range is permitted after outputting a warning signal. Erroneous operation prevention device for the automatic transmission control mechanism.