JP4836855B2 - Shift mechanism of automatic transmission - Google Patents

Description

  The present invention relates to a shift mechanism for an automatic transmission.

In a vehicle equipped with an automatic transmission, the shift lever of the automatic transmission is configured so that a D range that is a forward travel range, an R range that is a reverse travel range, and a P or N range that is a parked range can be selected. Yes. Patent Document 1 discloses a configuration in which each range is provided in a line in the order of P−R−N−D.
Japanese Patent Laid-Open No. 05-231537

  For example, when the parking operation for parking the vehicle at a predetermined position is started, the driver releases the brake pedal in the D range or the R range and tries to move the vehicle by the creep force. Since the driving force is insufficient, the accelerator pedal must be depressed. Thereafter, when the vehicle advances to a predetermined position, it is necessary to step on the brake pedal in order to stop the vehicle. Thus, since it is necessary to step on the accelerator pedal and the brake pedal alternately in order to park the vehicle, the operation of the driver becomes complicated.

  As described above, when the vehicle is in a traveling state different from that during normal forward and reverse traveling, it may be preferable to perform some control different from that during normal traveling. However, each of the D range and the R range is only one each. Since it is not provided, it is not possible to perform control different from that during normal driving.

  An object of the present invention is to provide a shift mechanism for performing control different from that during normal traveling when the vehicle is in a traveling state different from that during normal traveling.

The present invention provides an automatic transmission having a first shift mechanism capable of selecting each position of a first forward travel range, a first reverse travel range, and a first neutral range by a shift lever. Each range position of the travel range, the second reverse travel range, and the second neutral range can be selected by the shift lever, and the second shift mechanism provided by branching from the first shift mechanism and the shift lever can The second forward travel range and the second reverse travel range are selected by the parking operation determination means for determining whether or not the second forward travel range and the second reverse travel range are selected. Engine control means for controlling the engine .

  According to the present invention, the second shift mechanism is provided by branching from the first shift mechanism, and the forward travel range and the reverse travel range are provided in the first shift mechanism and the second shift mechanism, respectively. When the driving state is different from that of the vehicle, the driver can perform control different from that during normal driving by operating the shift lever.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a configuration of a shift mechanism of an automatic transmission according to the present embodiment. In the automatic transmission according to the present embodiment, the automatic transmission control unit (TCU) 1 receives signals from the select switch 2, the engine control unit (ECU) 3, and the obstacle alarm device 4, and based on these signals. A transmission signal is transmitted to the transmission mechanism 8 and a control signal is output to the vehicle attitude control device (ESP) 5 and the ECU 3.

  The select switch 2 can switch the travel range of the automatic transmission by operating the shift lever 6 by the driver. The P and N ranges (first neutral range) are selected when the vehicle is parked, and the output of the engine 9 is not input to the transmission mechanism 8. The R range (first reverse travel range) is a range selected when the vehicle is moved backward. The D, 2, and L ranges (first forward travel range) are ranges that are selected when the vehicle is advanced. When the D range is selected, an optimum gear position is set based on the vehicle speed and the throttle opening. When the two range is selected, automatic shift is performed using only the first speed and the second speed. When the L range is selected, the first speed is fixed and the engine brake is activated.

  The above range is the normal range (first shift mechanism). Here, for example, when the vehicle is parked in a desired space, such as in a garage, the forward and backward movement of the vehicle needs to be repeated, so that the shift lever 6 is repeatedly switched from the R range to the D range. This operation is complicated for the driver, and if the accelerator pedal is depressed too much when in the D range or R range due to a driver's operation error, the vehicle may start suddenly. Therefore, in the shift mechanism of the automatic transmission according to this embodiment, in addition to the normal range, a parking-only range 10 (second shift mechanism) used when the vehicle is parked is provided.

  The parking exclusive range 10 is provided on the side of the N range of the normal range 7 so that the shift lever 6 can be contacted by moving the shift lever 6 laterally from the position of the N range. The parking dedicated range 10 further includes a parking forward range (second forward travel range), a parking N range (second neutral range), and a reverse parking range (second reverse travel range) in order from the front. When the shift lever 6 is moved laterally from the N range, the parking N range is set. By moving the shift lever 6 forward from the parking N range, the parking forward range is moved backward from the parking N range. Set to the reverse parking range.

  The ECU 3 controls the throttle opening based on the driver's accelerator pedal operation amount or the control signal received from the TCU 1 and transmits the detected rotational speed and throttle opening of the engine 9 to the TCU 1.

  The obstacle alarm device 4 detects the distance between the vehicle and the obstacle using an infrared sensor or the like, and transmits the distance between the vehicle and the obstacle to the TCU 1.

  The ESP 5 controls the distribution of driving force to the driving wheels and the braking force distribution of the wheels in order to improve the running stability of the vehicle.

  The TCU 1 controls the ESP 5 and the ECU 3 based on the range signal transmitted from the select switch 2, the engine speed and throttle opening transmitted from the ECU 3, and the distance between the vehicle and the obstacle transmitted from the obstacle alarm device 4. A signal is transmitted to control the torque of the engine 9 and the braking / driving force of the vehicle.

  The shift mechanism of the automatic transmission is configured as described above, and the TCU 1 controls the automatic transmission based on the range position of the shift lever 6 selected by the driver. Here, the control performed in the TCU 1 when the parking-only range 10 is selected will be described with reference to the flowchart of FIG. This control is repeatedly executed every minute time.

  In step S1 (parking operation determination means), it is determined whether the parking forward range or the parking backward range is selected. When the parking forward range or the parking backward range is selected, the process proceeds to step S2, and when neither is selected, the process is terminated. The selection of the parking forward range or the parking backward range is determined by whether or not the shift lever 6 is in the parking forward range or the parking backward range.

  In step S2 (idle rotation control means), the idle rotation speed is increased. The idle rotation speed is set higher than the D range and the R range so that the creep force increases and the driver can move the vehicle forward or backward without pressing the accelerator pedal as much as possible.

  In step S3 (output reduction determination means), it is determined whether or not the vehicle has started suddenly. If it is determined that the vehicle has started suddenly, the process proceeds to step S4. If it is determined that the vehicle has not started suddenly, the process proceeds to step S5. The sudden start of the vehicle is determined by the vehicle speed being higher than a predetermined speed, the throttle opening being larger than the predetermined opening, the engine speed being higher than the predetermined rotation, or the like. The predetermined speed, the predetermined opening, and the predetermined rotation are values that can be used to determine that the vehicle has started suddenly, and are obtained in advance through experiments or the like.

  In step S4 (output reduction means), the engine output is reduced by the ECU 3. The ECU 3 reduces the engine output by reducing the throttle opening of the engine 9.

  In step S5, it is determined whether the distance between the vehicle and the obstacle is a parking collision danger distance. When the distance between the vehicle and the obstacle is the parking collision danger distance, the process proceeds to step S6, and when it is not the parking collision danger distance, the process is terminated. The parking collision danger distance is set to 30 cm or less, for example.

  In step S6, the vehicle is stopped by ESP5. The ESP 5 stops the vehicle by braking the wheel.

  That is, in the above control, when the driver operates the shift lever 6 and selects the parking forward range or the reverse parking range, it is determined that the vehicle is to be parked in a predetermined place, and the creep force is increased. If the driver depresses the accelerator pedal too much, the engine output is reduced to prevent sudden start.

As described above, in this embodiment, the parking range 10 is provided in addition to the normal range 7, and it is determined that the parking operation is performed when the parking forward travel range and the parking backward travel range are selected, and the engine 9 Therefore, when the parking operation of the vehicle is started, it is possible to prevent the depression operation of the accelerator pedal and the brake pedal from becoming complicated by setting a control different from that during normal driving (claims). 1 ).

When it is determined that the parking operation is being performed, the idle rotation speed is increased, so that the creep force increases, and the vehicle is parked in a predetermined space, and when forward and reverse are repeated, The vehicle can be moved forward and backward smoothly without stepping on the accelerator pedal as much as possible. Therefore, it is possible to prevent the operation of depressing the accelerator pedal and the brake pedal from being complicated when the vehicle is parked (corresponding to claim 2 ).

Further, when it is determined that the vehicle has started suddenly because the vehicle speed is higher than the predetermined speed, the throttle opening is larger than the predetermined opening, or the engine rotation speed is higher than the predetermined rotation, the output of the engine 9 is reduced. Therefore, when the driver repeatedly depresses the accelerator pedal and the brake pedal in order to park the vehicle, it is possible to prevent the vehicle from starting suddenly and running away due to an operation mistake (corresponding to claims 3 to 6 ). ).

Further, when the shift lever 6 is moved to any range position of the normal range 7, the control for reducing the engine output is stopped, so that the engine output is prevented from being limited when returning to the normal traveling state. Yes (corresponding to claim 7 ).

Furthermore, the parking range 10 is provided so as to branch from the N range of the normal range 7, so that the driver mistakenly selects the parking range 10 even when the parking operation is not being performed, and the engine output is reduced. Even if the control for stopping the vehicle is performed, it is possible to prevent the driver from feeling uncomfortable (corresponding to claim 8 ).

  The present invention is not limited to the embodiment described above, and various modifications and changes can be made within the scope of the technical idea.

  For example, in the parking dedicated range 10, the parking advance range is arranged in the front and the parking backward range is arranged in the rear. However, the parking backward range may be arranged in the front and the parking advance range may be arranged in the rear.

Moreover, although the parking exclusive range 10 was provided in the side of N range, you may provide in the side of P range or R range. Since the driving wheel is locked by the parking mechanism when the P range is selected, it is preferable to provide it on the side of the N range, but the shift lever 6 and the speed change mechanism 8 are mechanically connected like a shift-by-wire. In a configuration that is not, it can also be placed to the side of the P range. Further, when the R range is selected, the vehicle is running at a low speed even if the vehicle is traveling. Therefore, the driver erroneously selects the parking-only range 10 and performs control for reducing the engine output or stopping the vehicle. Even if it is, the driver can be prevented from feeling uncomfortable (corresponding to claim 8 ).

It is a schematic block diagram which shows the structure of the shift mechanism of the automatic transmission in this embodiment. It is a flowchart which shows control of the shift mechanism of the automatic transmission in this embodiment.

Explanation of symbols

1 TCU
2 Select switch 3 ECU
4 Obstacle alarm device 5 ESP
6 Shift lever 7 Normal range (first shift mechanism)
9 Engine 10 Parking-only range (second shift mechanism)

Claims (8)

In an automatic transmission including a first shift mechanism that can select each range position of a first forward travel range, a first reverse travel range, and a first neutral range by a shift lever,
A second shift mechanism that is provided by branching from the first shift mechanism, wherein each range position of the second forward travel range, the second reverse travel range, and the second neutral range can be selected by the shift lever. When,
Parking operation determining means for determining whether or not the second forward travel range and the second reverse travel range are selected by the shift lever;
Engine control means for controlling the engine when it is determined by the parking operation determination means that the second forward travel range and the second reverse travel range are selected;
An automatic transmission comprising: The engine control means determines the engine idling rotational speed as the first forward travel when the parking operation determination means determines that the second forward travel range and the second reverse travel range are selected. The automatic transmission according to claim 1, further comprising an idle rotation control unit configured to perform control so as to be higher than an idle rotation speed in the range and the first reverse travel range. Whether or not it is necessary to reduce the engine output based on the driving state of the vehicle when it is determined by the parking operation determination means that the second forward travel range and the second reverse travel range are selected. Further comprising an output decrease determining means for determining
  The engine control means includes output reduction means for controlling to reduce the output of the engine when it is determined that the output of the engine needs to be reduced. Automatic transmission. 4. The automatic transmission according to claim 3, wherein the output reduction determining means determines that the output of the engine needs to be reduced when the engine rotation speed exceeds a predetermined rotation. 5. The automatic transmission according to claim 3, wherein the output reduction determination unit determines that the output of the engine needs to be reduced when a throttle opening degree exceeds a predetermined opening degree. The automatic transmission according to any one of claims 3 to 5, wherein the output reduction determining means determines that the output of the engine needs to be reduced when the vehicle speed exceeds a predetermined speed. Machine. The output reduction means stops the control for reducing the output of the engine when the shift lever moves to any range position of the first shift mechanism. The automatic transmission according to any one of claims. The said 2nd shift mechanism has branched from the 1st neutral range in the said 1st shift mechanism, or the 1st reverse travel range, The any one of Claim 1-7 characterized by the above-mentioned. Automatic transmission.

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