JP2007055354A - Control device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress shocks generated after a parking lock mechanism is actuated. <P>SOLUTION: An ECU executes a program containing a step (S106) to determine whether a shift lever is in the position mating with the parking position if the vehicle speed is equal to or below the predetermined value (Yes at S102) and no less than the predetermined gradient (Yes at S104) after the brake is applied (Yes at S100) and a step (S110) to alter the pressure bleeding rate of the brake when the brake is turned off (S108) after the shift lever is moved to the position mating with the parking position (Yes at S106). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle control device, and more particularly to a technique for controlling a braking force of a vehicle when a parking lock mechanism is activated when a vehicle having a parking lock mechanism is stopped.

  2. Description of the Related Art Conventionally, a technique for eliminating a sudden sensation caused by releasing a braking force when a vehicle starts is known. For example, Japanese Patent Laid-Open No. 2000-351360 (Patent Document 1) discloses a brake fluid pressure holding device that eliminates a sudden sensation due to the release of the braking force when the vehicle starts. This brake hydraulic pressure holding device transmits the driving force from the prime mover to the drive wheels and also to the drive wheels when the travel range is selected in the transmission even when the accelerator pedal is depressed and released at a predetermined vehicle speed or less. Brake in a vehicle equipped with a driving force control device that switches the magnitude of the driving force between a large state and a small state according to the depression state of the brake pedal, and that makes the driving force smaller when the brake pedal is depressed than when the brake pedal is depressed It is a hydraulic pressure holding device. The brake hydraulic pressure holding device includes a hydraulic pressure passage that connects the master cylinder and the wheel cylinder, an electromagnetic valve that is provided in the hydraulic pressure passage and switches between a communication position that communicates with the hydraulic pressure passage and a shut-off position that blocks the hydraulic pressure passage. Even if the solenoid valve is in the shut-off position, it has a bypass path with a throttle that communicates the master cylinder and the wheel cylinder, and a controller that switches the solenoid valve between the communicate position and the shut-off position, and switches the solenoid valve to the shut-off position. Thus, the brake fluid pressure is applied to the wheel cylinder even after the brake pedal is released due to the restriction of the throttle flow rate. The control unit switches the electromagnetic valve to the communication position after a predetermined time has elapsed since the driving force increased to a large state.

According to the brake fluid pressure retaining device disclosed in the above-mentioned publication, the predetermined time has elapsed since the retention of the brake fluid pressure is not released when the drive force is increased to a large state, but the brake force is increased to a large state. Release brake fluid pressure later. Further, since the brake fluid pressure is gradually reduced by the throttle until a predetermined time elapses, the brake force is gradually released, and the brake force becomes small when the holding of the brake fluid pressure is released. Therefore, the sudden feeling at the time of starting the vehicle, which has been caused by releasing the braking force at once, is eliminated, and the shock at the time of starting due to this sudden feeling or the feeling of catching the brake at the time of starting is lost.
JP 2000-351360 A

  However, the above-mentioned publication does not consider the shock that occurs when the vehicle having the parking lock mechanism is stopped.

  The parking lock mechanism is a mechanism that limits the rotation of the shaft connected to the drive wheels when the shift lever moves to the parking position when the vehicle is stopped. For example, on a road surface having a slope, when the brake pedal is operated and the vehicle is stopped, the parking lock mechanism is activated when the shift lever is moved to the parking position. If the operation of the brake pedal is stopped after the parking lock mechanism is actuated, the road surface has a gradient, and thus a downward force due to its own weight acts on the vehicle. At this time, the shaft between the parking lock mechanism and the driving wheel is twisted. In particular, when the torsional torque is large, a backlash due to the elastic force (restoring force) of the shaft occurs. Therefore, the vehicle may swing back and forth until it converges to a position where the torsional torque generated on the shaft by its own weight and the elastic force (restoring force) of the shaft balance. As a result, there is a problem that the person on board feels uncomfortable.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a vehicle control device that suppresses a shock that occurs after the parking lock mechanism is operated.

  A vehicle control apparatus according to a first aspect of the present invention is a vehicle control apparatus having a parking lock mechanism that restricts rotation of a shaft coupled to drive wheels. The parking lock mechanism is provided in a transmission mounted on the vehicle, and restricts the rotation of the shaft in response to a shift lever that switches a power transmission state of the transmission moving to a predetermined position. The vehicle is provided with a braking device that develops braking force on the drive wheels. The control device includes position detection means for detecting the position of the shift lever, operation detection means for detecting whether or not the braking device has been operated, and control means for controlling the braking device. The control means is a means for controlling the braking device so that the braking force gradually decreases when the operation of the braking device is stopped after the shift lever is moved to a predetermined position in the stop state of the vehicle. Including.

  According to the first aspect of the present invention, when the operation of the braking device is stopped after the shift lever has moved to a predetermined position (for example, a parking position) while the vehicle is stopped, The braking device is controlled so as to gradually decrease. For example, if the shift lever is moved to the parking position while the vehicle is stopped on a road surface having a slope, the parking lock mechanism is activated. Even if the operation of the braking device is stopped after the operation of the parking lock mechanism, the braking force on the drive wheels is controlled to gradually decrease. Therefore, a downward force generated by its own weight due to the gradient on the road surface can be gently applied to the shaft. Alternatively, the downward acceleration of the vehicle that occurs when the parking lock mechanism shifts from the unrestricted state of the shaft to the restricted state can be reduced. Therefore, since the torsional torque applied to the shaft by its own weight and the elastic force of the shaft are moderately balanced, the rebound caused by the elastic force of the shaft is suppressed. Therefore, since the vehicle is suppressed from shaking back and forth, it can be suppressed that the person on board feels uncomfortable. Therefore, it is possible to provide a vehicle control device that suppresses a shock that occurs when the parking lock mechanism is operated.

  In addition to the configuration of the first invention, the vehicle control device according to the second invention further includes a gradient detecting means for detecting the gradient of the road surface on which the vehicle is located. In the vehicle stop state, the control means stops the operation of the braking device after the shift lever has moved to a predetermined position, and the detected gradient is equal to or greater than the predetermined gradient. And means for controlling the braking device to gradually reduce the braking force.

  According to the second aspect of the invention, in addition to stopping the operation of the braking device after the shift lever has moved to a predetermined position (for example, a parking position) while the vehicle is stopped. When the detected gradient is equal to or greater than a predetermined gradient, the braking device is controlled so as to gradually decrease the braking force. Thereby, when the vehicle is stopped on a road surface having a slope, the parking lock mechanism is activated when the shift lever is moved to the parking position. Even if the operation of the braking device is stopped after the operation of the parking lock mechanism, the braking force on the drive wheels is controlled to gradually decrease. Therefore, a downward force generated by its own weight due to the gradient on the road surface can be gently applied to the shaft. Alternatively, the downward acceleration of the vehicle that occurs when the parking lock mechanism shifts from the unrestricted state of the shaft to the restricted state can be reduced. Therefore, since the torsional torque applied to the shaft by its own weight and the elastic force of the shaft are moderately balanced, the rebound caused by the elastic force of the shaft is suppressed. Therefore, since the vehicle is suppressed from shaking back and forth, it can be suppressed that the person on board feels uncomfortable.

  In the vehicle control device according to the third aspect of the invention, in addition to the configuration of the first or second aspect of the invention, the parking lock mechanism is provided on the shaft, and includes a parking lock gear having a tooth portion along the rotation direction, and a tooth A parking lock pole that is supported by the transmission housing and a shift lever that moves to a predetermined position. Limiting means for matching and limiting the rotation of the shaft.

  According to the third invention, the parking lock mechanism limits the rotation of the shaft by matching the protrusion of the parking lock pole with the tooth. When the operation of the braking device is stopped after the parking lock mechanism is activated, the vehicle moves when the projection and the tooth part shift from the non-engagement state (unrestricted state) to the mesh state (restricted state). Acceleration may occur in the downward direction. Therefore, by gradually reducing the braking force on the drive wheels, the acceleration generated in the downward direction of the vehicle can be reduced. Therefore, since the torsional torque applied to the shaft by its own weight and the elastic force of the shaft are moderately balanced, the rebound caused by the elastic force of the shaft is suppressed. Therefore, it is suppressed that the vehicle shakes back and forth.

  In the vehicle control device according to the fourth invention, in addition to the configuration of any one of the first to third inventions, the braking device includes a master cylinder for increasing the hydraulic pressure in response to an increase in the operation amount, A wheel cylinder that is provided in each of the wheels and generates frictional force by increasing the hydraulic pressure to limit the rotation of the wheel; a hydraulic pressure passage connecting the master cylinder and the wheel cylinder; and a hydraulic pressure in the hydraulic pressure passage Fluid pressure control means for controlling increase / decrease.

  According to the fourth invention, the hydraulic pressure control means controls increase / decrease of the hydraulic pressure in the hydraulic pressure passage. Therefore, the control means can gradually reduce the braking force on the drive wheels by gradually reducing the hydraulic pressure in the hydraulic pressure passage by the hydraulic pressure control means.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  A vehicle equipped with a vehicle control device according to an embodiment of the present invention will be described with reference to FIG. This vehicle is an FF (Front engine Front drive) vehicle. The vehicle equipped with the vehicle control device according to the present embodiment may be a vehicle other than FF.

  The vehicle includes an engine 102, a transmission 104, drive shafts 120 and 122, front wheels 124 and 126, a brake booster 136, a master cylinder 106, a brake actuator 108, a hydraulic circuit 110, a brake mechanism 112, ECU (Electronic Control Unit) 100.

  The engine 102 is an internal combustion engine that burns a mixture of fuel and air injected from an injector (not shown) in a combustion chamber of a cylinder. The piston in the cylinder is pushed down by the combustion, and the crankshaft is rotated. An external combustion engine may be used instead of the internal combustion engine. Further, a rotating electrical machine or the like may be used instead of the engine 102.

  The transmission 104 shifts the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear stage. The output gear of the transmission 104 is meshed with a differential gear provided inside the housing of the transmission 104. Drive shafts 120 and 122 are connected to the differential gear by spline fitting or the like. Power is transmitted to the left and right front wheels 124 and 126 via the drive shafts 120 and 122.

  A brake disc 138 is provided at one end of the drive shaft 122 on the front wheel 126 side. The brake disc 138 is provided with a brake mechanism 112. The brake mechanism 112 includes a wheel cylinder, and the wheel cylinder is provided so as to sandwich the brake disc 128 via a brake pad. The brake mechanism 112 is connected to one end of the hydraulic circuit 110. When the hydraulic pressure in the hydraulic circuit 110 increases, the hydraulic pressure applied to the wheel cylinder increases. As the hydraulic pressure increases, the force with which the wheel cylinder pinches the brake disc via a brake pad (not shown) increases. When the frictional force generated between the brake pad and the brake disk increases, the rotation of the front wheel 126 is limited. Therefore, when the hydraulic pressure in the brake mechanism 136 increases, a braking force corresponding to the increased hydraulic pressure is generated in the vehicle. The brake mechanism 112 is provided on each vehicle wheel. In the present embodiment, the brake mechanism 112 has been described as a disc brake, but may be a drum brake, for example.

  Master cylinder 106 is connected to the other end of hydraulic circuit 110. The master cylinder 106 is provided with a piston (not shown) inside. Then, when the piston moves in response to an input from the brake booster 136, the hydraulic pressure in the master cylinder 106 increases, and the hydraulic pressure in the hydraulic circuit 110 increases accordingly.

  The brake booster 136 uses the negative pressure on the intake side during operation of the engine 102 to boost the pedaling force input to the brake pedal 132 and transmits it to the master cylinder 106. Note that the structure and operation of the brake booster 136 are well-known techniques and will not be described in detail here.

  The master cylinder 106 and the hydraulic circuit 110 are connected via a brake actuator 108. The brake actuator 108 includes a solenoid valve and an electric pump. The brake actuator 108 receives a control signal from the ECU 100, operates the electromagnetic valve and the electric pump, and raises or lowers the hydraulic pressure in the hydraulic circuit 110. The hydraulic circuit 110 is a liquid passage (pipe) that is connected from the brake actuator 108 to the brake mechanism 112 and is filled with brake fluid.

  In the present embodiment, the brake pedal 132, the brake booster 136, the master cylinder 106, the brake actuator 108, the hydraulic circuit 110, and the brake mechanism 112 constitute a “braking device”.

  The ECU 100 includes a vehicle speed sensor 118, a position switch 116 of the shift lever 114, a stop lamp switch 130 provided on the brake pedal 132, a hydraulic pressure sensor 128 and a gradient sensor 134 of the master cylinder 106 via a harness or the like. Are electrically connected.

  The vehicle speed sensor 118 detects the vehicle speed from the rotational speed of the drive shaft 120 and transmits a signal representing the vehicle speed to the ECU 100. The vehicle speed sensor 118 is provided on each wheel of the vehicle.

  The position switch 116 detects the position of the shift lever 114. The position switch 116 transmits a signal indicating the position of the shift lever 114 to the ECU 100. Corresponding to the position of the shift lever 114, the gear stage of the transmission 104 is automatically formed.

  The stop lamp switch 130 detects the on / off state of the brake pedal 132 and transmits a signal representing the detection result to the ECU 100. Instead of the stop lamp switch 130, a stroke sensor that detects the stroke amount of the brake pedal 132 may be provided. The hydraulic pressure sensor 128 detects the hydraulic pressure inside the master cylinder 106 and transmits a signal representing the hydraulic pressure to the ECU 100.

  The gradient sensor 134 detects the gradient of the road surface by detecting the inclination angle of the vehicle. Gradient sensor 134 transmits a signal representing the detection result to ECU 100. The gradient sensor 134 is realized by a G sensor, for example.

  The ECU 100 determines the vehicle based on the signals sent from the vehicle speed sensor 118, the position switch 116, the stop lamp switch 130, the hydraulic pressure sensor 128, the gradient sensor 134, a map and a program stored in a ROM (Read Only Memory). Are controlled so as to be in a desired state. The vehicle control apparatus according to the present embodiment is realized by ECU 100.

  In the present embodiment, parking lock mechanism 200 is provided inside transmission 104. The parking lock mechanism 200 may be provided on any shaft between the front wheels 124 and 126 and the transmission 104, and is not particularly limited to the inside of the transmission 104. In the present embodiment, transmission 104 is an automatic transmission, but is not limited to an automatic transmission.

  As shown in FIG. 2, the parking lock mechanism 200 includes a parking lock gear 202 and a parking lock pole 206. In the present embodiment, parking lock gear 202 may be provided on the output shaft of transmission 104 or may be provided on the shaft of a gear meshed with the output shaft. The parking lock gear 202 has a disk shape and is provided with a plurality of tooth portions 204 along the rotation direction of the shaft 212.

  The parking lock pole 206 is supported by the housing of the transmission 104 so that one end thereof is rotatable. A protrusion 208 that matches the tooth portion 204 of the parking lock gear 202 is provided at the center of the parking lock pole 206. A parking lock cam 210 is provided at the other end of the parking lock pole 206 so as to contact the parking lock pole 206. The parking lock cam 210 has, for example, a conical shape, and when the parking lock cam 210 moves from the back side to the front side in FIG. 2, the other end of the parking lock pole 206 is along a conical inclined portion. And rotate in the direction of the arrow in FIG. The parking lock cam 210 moves from the back side to the near side in FIG. 2 in response to the shift lever 114 moving to a position corresponding to the parking position. At this time, the parking lock pole cam 210 may be driven by a mechanism that mechanically interlocks with the shift lever 114 or may be driven by an electric motor. When the projection 208 of the parking lock pole 206 is moved to a predetermined position that matches the tooth portion 204 of the parking lock gear 202 by driving the parking lock cam 210, the rotation of the parking lock gear 202 is restricted. Thus, the parking lock mechanism 200 is actuated to restrict the rotation of the front wheels 124 and 126.

  In the vehicle having such a configuration, when the operation of the brake pedal 132 is stopped after the parking lock mechanism 200 is operated in a stopped state on a sloped road surface, the vehicle is lowered in the downward direction due to the weight of the vehicle. Power works. At this time, the shaft between the parking lock mechanism and the drive wheel is twisted. In particular, when the slope of the road surface is steep, or when the toothed portion 204 of the parking lock gear 202 and the protruding portion 208 of the parking lock pole 206 shift from the non-engaged state to the engaged state, the vehicle amount decreases. If this torsional torque is large due to the occurrence of acceleration in the direction, there may be a case where the shaft is turned back due to the elastic force (restoring force). Therefore, the vehicle may swing back and forth until it converges to a position where the torsional torque generated on the shaft by its own weight and the elastic force (restoring force) of the shaft balance. For this reason, there is a problem that the person on board feels uncomfortable.

  Therefore, according to the present invention, when the operation of the brake pedal 132 is stopped after the shift lever 114 is moved to a predetermined position after the ECU 100 is stopped on a road surface having a slope, the braking force gradually decreases. In this way, the brake actuator 108 is controlled.

  Specifically, when the vehicle is stopped by the driver's operation of the brake pedal 132 and the driver moves the shift lever 114 to the parking position, the ECU 100 determines that the road surface is equal to or greater than a predetermined gradient, When it is detected that the operation of the brake pedal 132 is stopped after the shift lever 114 is moved to the parking position, that is, the brake pedal 132 is operated to the release side, the hydraulic pressure in the hydraulic circuit 110 gradually decreases. The brake actuator 108 is controlled.

  Hereinafter, with reference to FIG. 3, a control structure of a program executed by ECU 100 that is the control device for the vehicle according to the present embodiment will be described.

  In step (hereinafter, step is described as S) 100, ECU 100 determines whether or not the brake is on (operated). The ECU 100 determines that the brake is turned on (operated) when receiving an on signal from the stop lamp switch 130, and determines that the brake is turned off (operation is stopped) when receiving an off signal. To do. When the stroke sensor of the brake pedal 132 is used instead of the stop lamp switch 130, the ECU 100 determines that the brake is turned on, for example, when the detected stroke amount is equal to or greater than a predetermined stroke amount. If it is determined and the stroke amount is smaller than a predetermined stroke amount, it may be determined that the brake is off. If the brake is on (YES in S100), the process proceeds to S102. Otherwise (NO in S100), this process ends.

  In S102, ECU 100 determines whether or not the vehicle speed is equal to or lower than a predetermined vehicle speed. ECU 100 determines whether or not the vehicle speed corresponding to the wheel speed received from wheel speed sensor 118 is equal to or lower than a predetermined vehicle speed. Note that the “predetermined vehicle speed” is a vehicle speed in a substantially stopped state at an extremely low speed. If the vehicle speed is equal to or lower than the predetermined vehicle speed (YES in S102), the process proceeds to S104. Otherwise (NO in S102), this process ends.

  In S104, ECU 100 determines whether or not the gradient is equal to or greater than a predetermined gradient. The ECU 100 determines whether or not the road surface gradient received from the gradient sensor 134 is greater than or equal to a predetermined gradient. The “predetermined gradient” is not particularly limited, and is adapted by an experiment or the like based on the weight of the vehicle, for example. If the road surface is equal to or greater than a predetermined gradient (YES in S104), the process proceeds to S106. Otherwise (NO in S104), this process ends.

  In S106, ECU 100 determines whether or not shift lever 114 is at a position corresponding to the parking (P) position. ECU 100 determines whether the signal representing the position of shift lever 114 received from position switch 116 is a signal corresponding to the parking position. If shift lever 114 is at a position corresponding to the parking position (YES in S106), the process proceeds to S108. If not (NO in S106), this process ends.

  In S108, ECU 100 determines whether or not the brake is off. If the brake is off (YES in S108), the process proceeds to S110. Otherwise (NO in S108), this process ends.

  In S110, ECU 100 changes the brake pressure release rate (reduction rate of hydraulic pressure). For example, ECU 100 controls brake actuator 108 such that the hydraulic pressure in hydraulic circuit 110 gradually decreases at a predetermined reduction rate. The predetermined decrease rate is a value adapted to prevent the vehicle from shaking back and forth when the brake pedal 132 is operated to the release side after the shift lever 114 has moved to the parking position. If there is, it will not be specifically limited.

  The operation of ECU 100, which is the vehicle control apparatus according to the present embodiment, based on the above-described structure and flowchart will be described with reference to FIG.

  As shown in FIGS. 4A and 4B, when the vehicle is traveling on a road surface having a predetermined gradient or higher, the driver operates the brake pedal 132 at time T (1). Then (YES in S100), stop lamp switch 130 is turned on, and the hydraulic pressure in master cylinder 106 increases to P (1) in accordance with the amount of operation of brake pedal 132.

  When the vehicle speed becomes a stop state equal to or lower than a predetermined vehicle speed (YES in S102), if the road surface gradient is equal to or higher than a predetermined gradient (YES in S104), FIG. Thus, at time T (2), after the driver moves shift lever 114 to a position corresponding to the parking position (YES in S106), it is determined whether or not operation of brake pedal 132 has been stopped. (S108).

  As shown in FIG. 4A, when the operation of brake pedal 132 is stopped at time T (3) (YES in S108), the hydraulic pressure in hydraulic circuit 110 is reduced at a predetermined rate. The brake actuator 108 is controlled to decrease.

  At this time, as shown by the broken line in FIG. 4 (B), if the hydraulic pressure is quickly reduced so as to correspond to the operation amount of the brake pedal 132 at time T (3), FIG. As indicated by the broken line, the vehicle quickly starts moving in the downward direction due to its own weight, and the vehicle shakes back and forth. This is because when the brake pedal 132 is operated to the release side, a force is applied in the downward direction due to its own weight, or there is a backlash (between the teeth 204 of the parking lock gear 202 and the projections 208 of the parking lock pole 206 ( This is due to the occurrence of acceleration that causes the vehicle to move in the downward direction when the gap) is clogged, or when the tooth portion 204 and the protruding portion 208 are moved from the non-engaged state to the engaged state. Due to the generated acceleration, a torsional torque is applied to the shaft between the parking lock mechanism and the drive wheel, and an elastic force is generated against the torsional torque against the torsional torque, causing the vehicle to swing back and forth. . The forward / backward vibration generated in the vehicle converges at a position where the torsion torque generated on the shaft due to its own weight and the elastic force of the shaft balance.

  On the other hand, as shown by the solid line in FIG. 4B, when the hydraulic pressure is gradually decreased from time T (3), the braking force on the front wheels 124 and 126 is gradually decreased. The acceleration to move in the direction is reduced. As a result, the torsional torque due to its own weight and the elastic force of the shaft balance gently, and as shown by the solid line in FIG. 4 (D), the vehicle slowly starts to move in the downward direction and restrains the vehicle from shaking back and forth. Is done.

  As described above, according to the control device for a vehicle according to the present embodiment, when the shift lever is moved to the parking position when the vehicle is stopped on a road surface having a slope, the parking lock mechanism is activated. . Even if the operation of the brake pedal is stopped after the operation of the parking lock mechanism, the braking force on the front wheels is controlled to gradually decrease. Therefore, a downward force generated by its own weight due to the gradient on the road surface can be gently applied to the shaft. Alternatively, it is possible to reduce the acceleration in the downward direction of the vehicle that occurs when the parking lock mechanism shifts from the non-engagement state of the shaft to the engagement state. Therefore, since the torsional torque applied to the shaft by its own weight and the elastic force of the shaft are moderately balanced, the rebound caused by the elastic force of the shaft is suppressed. Therefore, since the vehicle is suppressed from shaking back and forth, it can be suppressed that the person on board feels uncomfortable. Therefore, it is possible to provide a vehicle control device that suppresses a shock that occurs when the parking lock mechanism is operated.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the structure of the vehicle carrying the vehicle control apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of a parking lock mechanism. It is a flowchart which shows the control structure of the program performed with ECU which is the control apparatus of the vehicle which concerns on embodiment of this invention. It is a timing chart which shows operation | movement of EUU which is the control apparatus of the vehicle which concerns on embodiment of this invention.

Explanation of symbols

  100 ECU, 102 Engine, 104 Transmission, 106 Master cylinder, 108 Brake actuator, 110 Hydraulic circuit, 112 Brake mechanism, 114 Shift lever, 116 Position switch, 118 Wheel speed sensor, 120, 122 Drive shaft, 124, 126 Front wheel, 128 hydraulic sensor, 130 stop lamp switch, 132 brake pedal, 134 gradient sensor, 136 brake booster.

Claims (4)

A control device for a vehicle having a parking lock mechanism for restricting rotation of a shaft connected to a drive wheel, wherein the parking lock mechanism is provided in a transmission mounted on the vehicle, and a power transmission state of the transmission The vehicle is provided with a braking device that restricts the rotation of the shaft in response to the shift lever moving to a predetermined position and expresses the braking force on the drive wheels,
Position detecting means for detecting the position of the shift lever;
Operation detecting means for detecting whether or not the braking device is operated;
Control means for controlling the braking device,
The control means is configured to cause the braking force to gradually decrease when the operation of the braking device is stopped after the shift lever is moved to the predetermined position when the vehicle is stopped. A vehicle control device including means for controlling the vehicle. The control device further includes a gradient detecting means for detecting a gradient of a road surface on which the vehicle is located,
The control means determines the detected gradient in addition to stopping the operation of the braking device after the shift lever has moved to the predetermined position in the stop state of the vehicle. The vehicle control device according to claim 1, further comprising means for controlling the braking device so as to gradually reduce the braking force when the slope is equal to or greater than a predetermined gradient. The parking lock mechanism is
A parking lock gear provided on the shaft and having a tooth portion along a rotation direction;
A parking lock pole having a protrusion that matches the tooth portion and supported by a housing of the transmission;
Limiting means for limiting the rotation of the shaft by matching the protruding portion of the parking lock pole with the tooth portion in response to the shift lever moving to the predetermined position. The vehicle control device according to claim 1. The braking device is:
A master cylinder that increases the hydraulic pressure in response to an increase in the amount of operation of the braking device;
A wheel cylinder that is provided on a wheel of the vehicle and generates a frictional force by increasing the hydraulic pressure to restrict rotation of the wheel;
A liquid passage connecting the master cylinder and the wheel cylinder;
The vehicle control device according to any one of claims 1 to 3, further comprising a fluid pressure control means for controlling increase / decrease in fluid pressure in the fluid passage.

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