JPH05223167A - Wrong operation prevention device for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent wrong operation from happening by calculating time between count signals which are generated according to up-and-down operation of a shift lever and cancelling the count signal when the measured value is less than the prescribed value. CONSTITUTION:A select switch SW is switched each time when a shift range of an automatic transmission AT is selected by operation of a shift lever the shift range of the automatic transmission AT is switched from D range to 3, 2, or L range by a count signal starting from the switch SW. At that time, whenever a count signal is produced, elapsed time from the latest count signal which is N number before the generation to the present time is measured in a range controller 20. The judgement is made wether the measured time is within the preset prescribed time, and if the answer is YES, the shift lever is judged to be operated in the prescribed time at short intervals, so that the count signals at present is cancelled and switched to D range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an erroneous operation preventing device for an automatic transmission control mechanism in which selection of a plurality of shift ranges in an automatic transmission is realized by electrical control.

[0002]

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

For example, in Japanese Utility Model Laid-Open No. 61-18944, electrical contacts are switched according to the operation of a lever, and the shift range of an automatic transmission is based on a signal output from a control unit connected to the electrical contacts. A configuration for selecting is disclosed. Moreover, in this structure, the signal for range switching is output from the control unit only when the electrical contact is turned on for a predetermined time or longer.

[0004]

In the prior art of the above publication, when selecting the shift range, the shift range is not achieved unless the lever is stopped at the target range position for a certain period of time or longer. This avoids the situation that the shift range of the automatic transmission is frequently changed at the time of operating the lever, while the operability becomes a problem when quick range change is required. For example, switching from the drive (D) range to the other forward traveling range such as the third (3) range, the second (2) range, or the low (L) range is often required to be quick and good in operability. The technique disclosed in the above publication cannot cope with this.

A technical problem of the present invention is that it is possible to control switching of a plurality of forward traveling ranges including a drive range by a count signal associated with an up / down operation of a shift lever, and a predetermined operation is performed by a driver operating the shift lever due to an erroneous operation or play. When the count signal is frequently transmitted within the time period, the forward travel range is prohibited from being switched, thereby preventing an adverse effect on the automatic transmission due to an erroneous operation without impairing the operability of the shift lever.

[0006]

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

That is, there is provided a switch which is switched by a shift operation of the shift lever, and a range control section which outputs a control signal for selecting a shift range of the automatic transmission in accordance with an electric signal from the switch. The shift range of the automatic transmission is switched to a plurality of forward drive ranges including the drive range by the count signal output from the switch by operating the shift lever up and down in the drive range position in a direction intersecting with the shift operation direction. In the control mechanism for automatic transmission,
The range control unit is a measuring unit that measures a time from a count signal a predetermined number of times before each count signal accompanying the up-down operation of the shift lever, and if the measured value is a predetermined time or less, And a control means for canceling the count signal at this time and controlling the shift range of the automatic transmission by switching to the drive range.

[0008]

According to this structure, even if the shift lever is frequently operated up or down by an erroneous operation or a play operation by the driver, if the value measured by the measuring means of the range control unit is less than the predetermined time, The control means of the range control unit cancels the count signal based on the up / down operation and switches the shift range of the automatic transmission to the drive range.

Therefore, it is possible to avoid switching the forward drive range of the automatic transmission in response to the frequently transmitted count signal. When the range switching control is frequently performed within the predetermined time as described above, the hydraulic transmission is likely to be simultaneously supplied to the friction engagement devices before and after the switching on the automatic transmission side. Is prevented from being adversely affected.

[0010]

Embodiments of the present invention will now 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. As is apparent from this drawing, a shift lever 10 is arranged on the left side of the steering column portion 14 near the steering wheel 12. By operating the shift lever 10, the select switch SW for selecting the shift range of the automatic transmission AT, which will be described later, is switched. In FIG. 2, the 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.

FIG. 3 is a plan view showing each range position of the shift lever 10. As is apparent from this drawing, an operation line C1 for operating the shift lever 10 at each range position P, R for selecting the parking (P) range and the reverse (R) range of the automatic transmission.
And the operation line C2 for operating the shift lever 10 to each range position N, D for selecting the neutral (N) range and the drive (D) range are offset in parallel by a certain amount.

At the position of the range position D, a range position for selecting a forward traveling range (3, 2, L) other than the D range in the automatic transmission is provided on the operation line C3 orthogonal to the operation line C2. UP and DW are set so as to be distributed to both sides centering on the range position D. The shift lever 10 is moved from the range position D to the range position UP, along the operation line C3.
If you operate the DW and release the operating force,
Shift lever 1 by the function of a detent mechanism (not shown)
0 is returned to the range position D each time.

As described above, the shift lever 10 has the structure shown in FIG.
A shift operation along the operation lines C1 and C2 or an up-down operation along the operation line C3 from the range position D is possible. The select switch SW is switched by these operations of the shift lever 10.

FIG. 4 shows a system diagram of electric control for selecting the shift range of the automatic transmission AT. In this figure, an actuator (DC motor) 30 can switch a range switching valve (not shown) of the automatic transmission AT by driving the actuator. As is well known, the range switching valve is supplied with the line hydraulic pressure (basic hydraulic pressure) of the automatic transmission AT, and a friction engagement device (not shown) for setting each shift range by switching its discharge port. Engagement and release is controlled.

The range controller (SB shown in FIG. 4
W) 20 is a read-only memory (ROM) in which a microcomputer is used to store a program necessary for various software processes for switching the shift range of the automatic transmission AT, and a central processing unit (CPU) for executing this program ( CPU), a writable memory (RAM) for temporarily storing variables necessary for a program, and the like.

A microcomputer is also used for the automatic shift control unit (ECT) 22 shown in FIG. 4, and this control unit 22 is known to automatically shift based on the vehicle speed and the engine load (throttle opening). It is possible to automatically control the gear AT of each gear.

Now, the range control unit 20 outputs an electric signal from the select switch SW which is switched based on the operation of the shift lever 10 and a valve position sensor 24 which detects the range position of the range switching valve. Detection signal is also input. In addition, the range control unit 2
From 0, a drive signal corresponding to the electric signal from the switch SW is output to the drive circuit 26 of the actuator 30, and a range signal based on the electric signals from the switch SW and the valve position sensor 24 is automatically transmitted. It is output to the control unit 22 and the range indicator 25, respectively.

On the other hand, in addition to the range signal from the range control unit 20, each detection signal from a vehicle speed sensor and a throttle sensor (not shown) is input to the automatic shift control unit 22, and the automatic shift control according to these signals. It is well known that the signal for is output to the automatic transmission AT.

When the shift lever 10 is shifted along the operation lines C1 and C2 shown in FIG. 3, the select switch SW shown in FIG. 4 is switched according to the range positions P, R, N and D at that time. Then, the electric signal associated therewith is input to the range control unit 20. Further, by operating the shift lever 10 from the range position D to the range position UP or the DW side along the operation line C3, the switch SW is moved to the range control unit 2 from the switch SW.
A count signal is transmitted to 0.

A drive signal corresponding to the signal from the switch SW is output from the range controller 20 to the drive circuit 26 of the actuator 30. Based on this, drive control of the actuator 30 switches the range switching valve (not shown) to select the shift range of the automatic transmission AT. The shift range of the automatic transmission AT is switched from the D range to the 3 range, the 2 range, or the L range by the count signal transmitted from the switch SW by the up / down operation of the shift lever 10.

That is, by operating the shift lever 10 from the range position D to the range position DW once, the shift range of the automatic transmission AT is changed to the previous D range.
The range is changed from the range to 3 ranges, and when the switch is turned on twice in succession, the range is changed to 2 and when it is turned on three times in succession, the range is changed to L.
On the contrary, when the shift lever 10 is operated to be moved up to the range position UP, the shift range of the automatic transmission AT is increased by one range L → 2 → 3 → D according to the number of times of operation.

When the shift range of the automatic transmission AT is switched and controlled in this way, the range indicator 25 shown in FIGS. The display area corresponding to the shift range is lit up. However, when the shift lever 10 is operated up and down in the range position D, the display portion of the D range of the range indicator 25 changes to "D", "3", "2", "L".

FIG. 1A is a flow chart showing the contents of software processing by the range control unit 20 when the shift lever 10 is operated up and down. Further, FIG. 1B shows one mode of the count signal transmitted from the switch SW by the up / down operation of the shift lever 10.

In the range control unit 20, as shown in FIG.
As shown in (B), each time the count signal is generated, the elapsed time T _N from the latest count signal N ₀ before that to the present time is measured each time. Therefore, Figure 1
In step S1 of (A), it is determined whether or not the measured time T _N is equal to or shorter than a predetermined time T ₀ set in advance. If the result of this determination is YES, the count signal is frequently generated within the predetermined time T ₀ , and this is regarded as an erroneous operation of the shift lever 10 or a driver's play operation, and the process proceeds to step S2. ..

After canceling the current count signal in step S2, the process proceeds to step S3. In step S3, the flag F is set to "1" and
The control range (shift range of the automatic transmission AT) is switched to the D range, and "D" of the range indicator 25 is set.
Outputs the signal to blink the display area of. The flag F is a flag for canceling the count signal and switching the control range to the D range.

If the result of the determination in step S1 is NO, that is, if the number of times the count signal is generated within the predetermined time T ₀ is normal, the process proceeds to step S4, in which the flag F has already been set (F = 1) or not. If the result of this determination is also no, in step S9 the control range is set to a count shift range that can be switched to each of the forward travel ranges described above based on the count signal.

If the result of the determination in step S4 is YES, the process proceeds to step S5 and it is determined whether or not the measurement time T _N is equal to or longer than a preset predetermined time T ₁ (T ₁ > T ₀ ). .. If the result of this determination is yes, the process for returning the canceled state of the count signal to the normal state is started.

That is, the process proceeds from step S5 to step S6, where the display portion of "D" of the range indicator 25 is changed from blinking to lighting, and the control range is changed from the D range to the count shift range in step S7. Further, in step S8, the flag F is set to "0".
To

If the result of the determination in step S5 is NO, it is too early to return the cancel state of the count signal to the normal state, and the process returns to step S2 again to perform the above-mentioned cancel processing. ..

[0031]

As described above, according to the present invention, when the count signal accompanying the up / down operation of the shift lever is frequently transmitted within a predetermined time, the switching of the forward traveling range is prohibited, and the shift range of the automatic transmission is changed. Since the drive range can be switched to a stable drive range, the adverse effect on the automatic transmission due to frequent transmission of the count signal can be prevented and the durability thereof can be improved without impairing the operability of the shift lever.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing control contents of a shift range when a shift lever is operated up and down.

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

FIG. 3 is a plan view showing a range position of a shift lever.

FIG. 4 is an electric system diagram for controlling a shift range of an automatic transmission.

[Explanation of symbols]

 10 shift lever 20 range control unit SW switch AT automatic transmission

Claims (1)

[Claims] 1. A switch, which is switched by a shift operation of a shift lever, and a range control section which outputs a control signal for selecting a shift range of an automatic transmission according to an electric signal from the switch, The shift range of the automatic transmission is switched to a plurality of forward drive ranges including the drive range by the count signal output from the switch by operating the shift lever up and down in the drive range position in a direction intersecting with the shift operation direction. In the control mechanism for the automatic transmission, the range control unit measures the time from a count signal a predetermined number of times before each count signal accompanying the up-down operation of the shift lever, and the measurement means. If the value is less than the specified time, the count signal at that time may be canceled. Erroneous operation preventing device for an automatic transmission control mechanism, characterized in that a control means for switching control of the shift range of the automatic transmission in the drive range.