JP3956962B2 - Parking lock device - Google Patents

Description

  The present invention relates to a parking lock device for a vehicle that locks a pair of left and right wheels.

  A typical automatic transmission is equipped with a parking lock mechanism that locks a pair of left and right wheels. Most parking lock mechanisms operate when a gear lever (selector lever) is placed in a parking position (P range). The conventional parking lock mechanism is performed by fixing the rotation of the gear inside the truss transmission. In a vehicle having a normal engine-transmission-drive wheel configuration, a pair of drive wheels (left and right wheels) can be locked simultaneously by locking with a transmission. Since the parking lock state is continued for a long time during parking, it is necessary to perform the mechanical engagement that does not consume energy during locking (however, energy may be consumed only during the locking operation).

In addition to the vehicle having the engine-transmission-drive wheel configuration described above, an in-wheel motor is provided along with the wheels, and a drive mechanism capable of driving a pair of left and right wheels (or all four wheels) independently of each other. There are also equipped vehicles. Such in-wheel motor vehicles have been put to practical use as carts for golf courses and carts for attractions in amusement facilities. In such an application, the parking lock mechanism is not always necessary. However, if in-wheel motors will become popular in passenger cars and the like in the future, it is necessary to consider providing a parking lock mechanism for in-wheel motor cars. As an in-wheel motor with a built-in lock mechanism, one described in [Patent Document 1] is known.
JP 2002-186115 A

  In an in-wheel motor vehicle, since a motor is provided for each pair of left and right wheels (or all four wheels), the pair of left and right wheels (or all four wheels) can be driven completely independently of each other. For this reason, there is no shared part in the mechanical part of the drive mechanism, and a parking lock mechanism must be provided for each motor (mechanical drive mechanism of each wheel). With the conventional automatic transmission described above, the drive wheels can be locked simultaneously if mechanically locked in the transmission, but this is not possible with an in-wheel motor vehicle.

  In the device described in [Patent Document 1], a mechanical lock mechanism is provided for each in-wheel motor. However, there was no guarantee that the left and right wheels would be locked at the same time. As described above, since the parking lock mechanically locks the drive mechanism, the engagement may not be completed in a single structure. Furthermore, if the gear lever is put into the parking lock position before the vehicle is completely stopped, the engagement is difficult to be performed. It is also conceivable that no action is taken. As a result, the lock timing of the left and right wheels may be shifted.

  If the right and left wheel lock timings shift, yaw is generated in the vehicle when traveling at a low speed, and the vehicle may rotate on a low μ road or the like. Further, even when the vehicle is completely stopped, if the vehicle is on a slope, if the left and right wheels are locked, the vehicle may change its direction. If the road is low, the vehicle may rotate as it is. . The same thing can happen when the parking lock is released if the release is not synchronized. Accordingly, an object of the present invention is to provide a parking lock device that can suppress unexpected vehicle behavior when executing / releasing parking lock.

  The parking lock device according to claim 1 includes a drive mechanism capable of driving the pair of left and right wheels independently of each other, and independently brakes the pair of left and right wheels without being operated by the driver. A hydraulic brake mechanism that can be fixed, a parking lock operation detecting means that detects whether the parking lock is executed or released, and a parking lock mechanism that mechanically fixes the pair of left and right wheels independently when the parking lock is executed. And a lock state detecting means for detecting the mechanically fixed state of the left and right wheels by the parking lock mechanism, and when a parking lock execution or release operation is detected by the parking lock operation detecting means, based on the detection result of the lock state detecting means. And a control means for braking or fixing at least one of the left and right wheels by a hydraulic brake mechanism. It is characterized in that there.

  In the parking lock device according to claim 2, when the parking lock operation detection unit detects the parking lock execution operation, the control unit applies at least the wheel on the side of the pair of left and right wheels on which the parking lock execution is delayed. On the other hand, the hydraulic brake is operated.

  According to a third aspect of the present invention, in the parking lock device according to the first aspect, when the parking lock release operation is detected by the parking lock operation detecting means, the control means releases at least the parking lock of the pair of left and right wheels. It is characterized by operating a hydraulic brake on the wheel on the faster side.

  According to a fourth aspect of the present invention, in the parking lock device according to any one of the first to third aspects, wheel rotation detection means for detecting wheel rotation, detection of the wheel rotation detection means, and lock state detection means. It further comprises failure diagnosis means for performing failure diagnosis based on the result.

  According to the parking lock device of the first aspect, when the parking lock is executed or released, the parking lock is locked by using the lock by the parking lock mechanism together with the fixing (braking) of the wheels by the hydraulic brake. It is possible to reliably synchronize (perform simultaneously) the lock execution / release of the left and right wheels. The fixing (braking) of the wheel by the hydraulic brake may be performed on both the pair of left and right wheels, or any one of them necessary for synchronization. When the vehicle is traveling (not completely stopped), the wheels are braked. When the vehicle is not traveling (completely stopped), the wheels are fixed.

  According to the parking lock device of the second aspect, when the parking lock is executed, the hydraulic brake is operated on at least the wheel on the side where the parking lock is delayed among the pair of left and right wheels. By doing in this way, the movement of the vehicle which is not intended by restraining only the wheel of one side mechanically can be suppressed. At this time, the parking wheel may be fixed (braking) by a hydraulic brake even though the parking lock has already been performed on the wheel on which the parking lock has been executed earlier.

  According to the parking lock device of the third aspect, when releasing the parking lock, the hydraulic brake is operated on at least one of the pair of left and right wheels on which the parking lock is released earlier. By doing in this way, the movement of the vehicle which is not intended by the one side wheel being cancelled | released mechanical fixation can be suppressed. At this time, the parking lock may be fixed to the wheel on the side where the parking lock release is late, even though the parking lock is not released yet.

  According to the parking lock device of the fourth aspect, the wheel rotation detection means detects whether or not the wheel is in a stopped state, and the lock state detection means detects whether or not the wheel is in a parking lock state. The failure can be accurately diagnosed based on the rotation state and the locked state of the wheel.

  Embodiments of the parking lock device of the present invention will be described below. FIG. 1 shows a configuration of a vehicle including the parking lock device of the present embodiment. The vehicle 1 has four wheels, a right front wheel FR, a left front wheel FL, a right rear wheel RR, and a left rear wheel RL, all of which include an in-wheel motor (drive mechanism) 2. For this reason, all the wheels can be driven completely independently of each other. To be able to drive completely independently means that it is possible to generate a completely different driving torque for each wheel.

  Each wheel is provided with a brake caliper 3 and constitutes a hydraulic brake mechanism together with a brake disk 4 fixed to the hub of each wheel. The hydraulic brake mechanism also includes a brake pedal 5, a master cylinder 6, and an actuator 7. The actuator 7 here refers to a pump for increasing the hydraulic pressure (brake hydraulic pressure), a plurality of valves for changing the hydraulic pressure transmission path and transmitting the increased hydraulic pressure to a desired wheel, and the like.

  The hydraulic brake mechanism of the present embodiment is generated by an ordinary brake control that performs braking by transmitting the hydraulic pressure generated in the master cylinder 6 to each brake caliper 3 when the driver depresses the brake pedal 5 and the actuator 7. It is possible to execute brake control in which the hydraulic pressure thus transmitted is transmitted to each brake caliper 3 to perform braking. The configuration of this hydraulic brake is the same as that of a normal brake mechanism with ABS. The actuator 7 of the hydraulic brake mechanism is connected to an ECU (Electronic Control Unit) 8 and its operation is controlled by the ECU 8.

  The ECU 8 is also connected with a stroke sensor 10 of the accelerator pedal 9 and a position sensor 12 of the gear lever 11. As described above, the vehicle 1 of the present embodiment is provided with the in-wheel motor 2 for each wheel, and by electrically controlling the driving torque of the in-wheel motor 2, it is equivalent to the conventional transmission by the transmission. Is doing that. For this reason, the gear lever 11 here has a conventional drive range mode (variable drive torque control based on the accelerator opening), low-speed gear fixed mode, second-speed start mode, reverse mode, parking lock mode, overdrive cancel mode, and the like. It is a lever for selecting. The position sensor 12 functions as a parking lock operation detection unit that determines that parking lock is requested when the gear lever 11 is in the parking lock mode position (P range).

  The ECU 8 is also connected to an inverter 13 that supplies electric power to the in-wheel motor 2 (see a thick solid line in FIG. 1). The inverter 13 supplies electric power from the battery 14 to each in-wheel motor 2 based on a command from the ECU 8. Each in-wheel motor 2 has a built-in sensor for detecting a rotational position called a resolver (see the dotted line in FIG. 1). The resolver is connected to the ECU 8. The resolver functions as wheel rotation detection means. Further, the vehicle speed (wheel speed) can be obtained from the detection result of the resolver, and the conventional vehicle speed sensor can be used with higher accuracy.

  In the vehicle 1 of the present embodiment, parking lock mechanisms 15 are disposed on the left and right rear wheels RR and RL. The parking lock mechanism 15 mechanically fixes the rotating portion of the in-wheel motor 2. For example, an engagement member (such as a plunger) that meshes with a reduction gear portion in the in-wheel motor 2 and stops rotating is electromagnetically driven. Execution / release of this lock is controlled by the ECU 8. Here, the above-mentioned plunger is electromagnetically driven by a drive signal from the ECU 8 to execute / release the lock.

  In addition, since it engages by engaging engagement members, such as a plunger, with a gear as mentioned above at the time of lock execution, if the phase of an engagement member and a gear does not match, a lock will not be completed. For this reason, there may be a case where it is impossible to completely grasp whether or not the locking is completed only by the execution command from the ECU 8. Therefore, here, a lock state detection sensor 15 a for detecting the position of the plunger and the like is incorporated in the parking lock mechanism 15. The ECU 8 can detect the lock state of the parking lock mechanism 15 based on the detection result of the lock state detection sensor 15a. That is, such a lock state detection sensor 15a and the ECU 8 function as a lock state detection unit. The state is maintained after the lock is executed or after the lock is released, and no electrical energy is required to maintain the state after the execution / release operation.

  The ECU 8 described above also functions as a part of a parking lock mechanism that mechanically fixes the left and right rear wheels RR and RL when the parking lock is executed. Further, the ECU 8 releases the mechanical fixing of the left and right rear wheels RR and RL when the parking lock is released. Further, as will be described in detail later, the ECU 8 also functions as a control unit that operates the hydraulic brake mechanism according to a predetermined condition when the parking lock is executed / released. Further, as will be described in detail later, the ECU 8 also functions as a failure diagnosis means for diagnosing whether or not the parking lock mechanism has failed based on the detection result of the resolver and the parking lock state.

  Hereinafter, parking lock execution / release control will be described. First, parking lock execution control will be described with reference to the flowchart of FIG. Note that the control of the flowchart of FIG. 2 is repeatedly executed at predetermined time intervals. First, the position sensor 12 detects whether or not an operation for moving the gear lever 11 to the parking lock position (P range) has been performed (step 200). If step 200 is negative, the control of the flowchart of FIG. 2 is finished as it is.

  On the other hand, when step 200 is affirmed, the resolver in the in-wheel motor 2 causes the wheel speed Nmr of the right wheel (here, the right rear wheel RR that performs parking locking) and the left wheel (here, parking locking is performed). The wheel speed Nml of the left rear wheel RL) is detected, and it is determined whether each exceeds a predetermined speed Nvhigh (step 205). The predetermined vehicle speed Nvhigh is set as a threshold value indicating that the vehicle speed is not so high as to perform parking lock. For example, when the gear lever 11 is operated to the P range by operating the gear lever 11 at a high speed, the parking lock mechanism is not activated by providing this step, and the parking lock mechanism can be prevented from being damaged. For this reason, when step 205 is affirmed and it is determined that the vehicle speed is high, the control of the flowchart of FIG. 2 is finished as it is.

  On the other hand, if step 205 is negative and it can be determined that the irregular state is not as described above, it is next determined whether or not the wheel speeds Nmr and Nml are each equal to or lower than a predetermined vehicle speed Nvstp1 (step 210). ). The predetermined vehicle speed Nvstp1 is set as a threshold value indicating that the vehicle speed is so low that the parking lock control may be executed. Therefore, if step 210 is negative and it is determined that the vehicle is not sufficiently decelerated, the control of the flowchart of FIG.

  On the other hand, when step 210 is affirmed, it is first determined whether or not the wheel speed Nmr of the right rear wheel RR is equal to or lower than a predetermined vehicle speed Nvstp2 (step 215). Here, Nvstp2 ≦ Nvstp1, and Nvstp2 is set as a threshold value indicating that the speed is so low that parking lock is possible. Normally, the parking lock is performed when the vehicle is stopped. However, depending on the driver, when the gear lever 11 is put in the P range just before the vehicle is stopped, or when the vehicle speed is slightly out even if the gear lever 11 is put into the P range at the same time as the vehicle is stopped, There is a case where the foot is released from the brake pedal 5 and the vehicle speed is slightly increased when the pedal is put in, and the predetermined vehicle speed Nvstp2 is set in consideration of these matters.

  Therefore, if step 215 is negative and it is determined that parking lock is not possible, the control of the flowchart of FIG. On the other hand, if step 215 is positive, a parking lock command for the right rear wheel RR is sent from the ECU 8 to the parking lock mechanism 15 for the right rear wheel RR, and the engagement member such as the plunger described above is driven ( Step 220). After step 220, it is similarly determined whether or not the wheel speed Nml of the left rear wheel RL is equal to or lower than a predetermined vehicle speed Nvstp2 (step 225). If step 225 is negative and it is determined that the parking lock is not possible, the control of the flowchart of FIG. 2 is finished, and if step 215 is affirmed, the parking lock command for the left rear wheel RL is sent from the ECU 8 to the right. It is sent to the parking lock mechanism 15 of the rear wheel RR, and the engaging member such as the plunger described above is driven (step 230).

  Then, after step 230, it is determined whether or not the wheel speeds Nmr and Nml are each equal to or lower than a predetermined vehicle speed Nvstp3 (step 235). Here, Nvstp3 ≦ Nvstp2, and Nvstp3 is set as a threshold value indicating that the vehicle is stopped (the wheel is not rotating), and is simply set to zero. However, on a hill or the like, although it can be said that the vehicle is in a stopped state, a slight rotation of the wheel may be detected, and such a predetermined vehicle speed Nvstp3 is set in consideration of this. If step 235 is negative, it can be determined that the vehicle is not stopped because either the right rear wheel RR or the left rear wheel RL (or both) is not locked. Then, both the left and right rear wheels RR and RL are braked (fixed) by the hydraulic brake mechanism at the same time (step 245).

  On the other hand, when step 235 is affirmed, it is next determined by the lock state detection means 15a whether the parking lock mechanism of the right rear wheel RR and the left rear wheel RL is in the lock state (step 240). As described above, the parking lock mechanism 15 may not be locked only when the parking lock command is sent out (in particular, the parking lock command is issued after the vehicle is completely stopped, and the phase between the engagement member and the gear described above). Etc.) Therefore, in this step, it is determined whether or not the parking lock is completed based on the detection result of the lock state detection means 15a. If step 240 is affirmed, it can be said that the left and right rear wheels RR and RL are simultaneously locked by the parking lock mechanism, and the control of the flowchart of FIG.

  On the other hand, if step 240 is negative, it can be determined that the parking lock of either the right rear wheel RR or the left rear wheel RL (or both) has not been completed. At the same time, braking (fixing) is performed by the hydraulic brake mechanism (step 245). Here, braking (fixing) by the hydraulic brake mechanism may be performed only on the left and right rear wheels RR and RL that are delayed in locking. In this way, since the left and right rear wheels RR and RL are simultaneously park-locked, the above-described problems can be avoided. The braking (fixed) by the hydraulic brake is released when the mechanical parking lock state of both the left and right rear wheels RR and RL is confirmed.

  Whether or not the mechanical fixing by the parking lock is completed can be detected only by the ECU 8. However, in this embodiment, the state of rotation of the wheel is detected by the resolver of the in-wheel motor 2, and the state of mechanical fixation by the parking lock is detected from these detection results (in this case, the in-wheel motor 2 It can be said that the resolver functions as a lock state detection means). It is also possible to detect whether the mechanical fixing by the parking lock has been completed by using both of them together.

  Next, parking lock release control will be described with reference to the flowcharts of FIGS. Note that the control of the flowcharts of FIGS. 3 and 4 is repeatedly executed at predetermined time intervals. First, it is detected by the position sensor 12 whether or not an operation for moving the gear lever 11 from the parking lock position (P range) has been performed (step 300). When step 300 is negative, the control of the flowcharts of FIGS. 3 and 4 is finished as it is.

  On the other hand, when step 300 is affirmed, it is determined whether or not the parking lock release flag is OFF (step 305). The parking lock release flag is ON when both the pair of left and right wheels (here, the left and right rear wheels RR and RL) are not mechanically fixed by the parking lock (in a released state), and mechanically fixed. This flag is turned OFF when If step 305 is negative and the mechanical lock by the parking lock has already been released, the control of the flowcharts of FIGS. 3 and 4 is finished as it is. As a case where step 305 is denied, immediately after the gear lever 11 is operated and put into the P range, the gear lever 11 is moved from the P range before the mechanical locking by the parking lock is completed. Can be mentioned.

  On the other hand, when step 305 is affirmed, both the left and right rear wheels RR and RL are mechanically fixed by parking lock. In this case, the left and right rear wheels RR and RL are next. The control for releasing the parking lock and the control for releasing the fixing (braking) by the hydraulic brake mechanism are executed (step 310). As a result, normally, the locked state of the left and right rear wheels RR and RL should be released, and the rotation should be possible. When the parking lock is executed, the lock is not completed unless the phases of the gear and the engaging member are matched, but when the parking lock is released, the meshed gear and the engaging member are disengaged. If there is no failure or the like in the parking mechanism 15, the locked state of the left and right rear wheels RR and RL is released at the same time.

  After step 310, it is detected whether the vehicle has moved (whether the wheel has rotated) (step 315). This is determined by determining whether either the wheel speed Nmr of the right rear wheel RR or the wheel speed Nml of the left rear wheel RL exceeds the above-described predetermined speed Nvstp1. When step 315 is affirmed, the vehicle non-stop counter is incremented (step 320), and when negative, the vehicle non-stop counter is cleared to zero (step 325). The vehicle non-stop counter counts a period during which the vehicle is not stopped.

  After step 320 or step 325, the parking lock release status is detected for each of the left and right rear wheels RR, RL. First, it is determined whether the mechanical fixing of the right rear wheel RR is released (step 330). This is determined based on whether or not the wheel speed Nmr of the right rear wheel RR exceeds the predetermined speed Nvstp1 described above. If step 330 is affirmed, the right parking lock release flag for the right rear wheel RR is set to ON (step 335), and if not, the right parking lock release flag is set to OFF (step 340). . The right parking lock release flag is a flag that is turned on when the right rear wheel RR is not mechanically fixed by the parking lock (in a released state), and is turned OFF when the mechanical fixation is performed. .

  After step 335 or step 340, the same is done for the left rear wheel RL. First, it is determined whether the mechanical fixation of the left rear wheel RL is released (step 345). This is determined by whether or not the wheel speed Nml of the left rear wheel RL exceeds the predetermined speed Nvstp1 described above. If step 345 is affirmed, the left parking lock release flag for the left rear wheel RL is set to ON (step 350), and if not, the left parking lock release flag is set to OFF (step 355). . The left parking lock release flag is a flag that is turned on when the left rear wheel RL is not mechanically fixed by the parking lock (in a released state), and is turned off when the mechanical fixation is performed. .

  After step 350 or step 355, it is determined whether or not the parking locks of the left and right rear wheels RR and RL are both released (step 360). This can be determined from the states of the right parking lock release flag and the left parking lock release flag described above. If both flags are ON, it is determined that the parking locks of the left and right rear wheels RR and RL are both released. it can. If step 360 is affirmed and it can be determined that both the left and right rear wheels RR and RL have been unlocked, the parking lock release flag described above is set to ON (step 365), and FIG. 3 and FIG. The control of the flowchart ends.

  On the other hand, if step 360 is denied and the parking lock of either one of the left and right rear wheels RR and RL is not released, the parking lock of the left and right rear wheels RR and RL may not be released simultaneously due to a failure of the parking mechanism 15 or the like. There is sex. In this case, first, the parking lock release flag described above is set to OFF (step 370). After that, in order to determine which of the left and right rear wheels RR and RL is released and which is not released, first, it is determined whether the right parking lock release flag is OFF and the left parking lock release flag is ON. Determination is made (step 380). If step 380 is affirmed, the right rear wheel RR is not unlocked and the left rear wheel RL is unlocked, that is, the left rear wheel RL is unlocked earlier. In this case, brake control by the hydraulic brake mechanism is performed on the left rear wheel RL (step 380). By doing in this way, the unexpected vehicle movement which arises when parking lock is cancelled | released only at the wheel of one side can be prevented reliably.

  On the other hand, if step 375 is negative, step 380 is skipped and the process proceeds to the next step. After step 380 or when step 375 is negative, it is determined whether the right parking lock release flag is ON and the left parking lock release flag is OFF (step 385). If step 385 is positive (this is the case when step 375 is negative), the right rear wheel RR is unlocked, but the left rear wheel RL is not unlocked, ie, the right rear wheel RR Is in a state where unlocking is earlier. In this case, brake control by the hydraulic brake mechanism is performed on the right rear wheel RR (step 390). Also in this case, it is possible to reliably prevent an unexpected vehicle movement caused by releasing the parking lock on only one wheel.

  On the other hand, if step 385 is negative, step 390 is skipped and the process proceeds to the next step. After step 380 or after step 375 is denied, it is determined whether the parking lock has been released for a specified time or longer (step 395). This is determined based on whether or not the vehicle non-stop counter described above exceeds a predetermined value Tvstp1. If step 395 is negative, it can be determined that the unlocking has been performed promptly, and the control of the flowcharts of FIGS. 3 and 4 ends. In the case where only one wheel is released from the parking lock and the other is under hydraulic brake control without being released from the parking lock, the control from step 300 is executed again after exiting the flowchart. In step 310, the parking lock release is retried.

  On the other hand, if step 395 is affirmed, it is determined that the parking lock has not been released easily, left and right parking lock control is executed on the assumption that there is some failure or malfunction, and left and right brake control by the hydraulic brake mechanism is executed. Then, the control of the flowcharts of FIGS. 3 and 4 is finished. In this case, it is assumed that some failure is certain, and the control in step 400 is executed to surely stop the vehicle.

  In the case of going through step 400, the driver is notified to that effect by a warning light or the like. When going through step 400, it is diagnosed that some sort of failure has occurred. In this way, the resolver of the in-wheel motor 2 can detect the rotation of the left and right rear wheels RR and RL, detect the parking lock state, and perform failure diagnosis based on the detection results.

  In this case as well, it is possible to detect whether or not the release of the mechanical fixing by the parking lock has been completed by the above-described lock state detection sensor 15a. Here, as in step 330 and step 345, the rotational state of the wheel is detected by the resolver of the in-wheel motor 2, and the state of mechanical fixation by the parking lock is detected from these detection results (in this case) It can be said that the resolver of the in-wheel motor 2 functions as a lock state detecting means). It is also possible to detect whether the mechanical fixing by the parking lock has been completed by using both of them together.

  Alternatively, for failure diagnosis, as shown in the flowchart of FIG. 5, part of the flowchart shown in FIG. 4 may be changed to determine which of the left and right rear wheels RR and RL has failed. . Hereinafter, the flowchart of FIG. 5 will be described. The first half of the flowchart of FIG. 5 is connected to each step of the flowchart of FIG. 4 as shown at the top of the flowchart of FIG. Here, step 395 is affirmed and it is determined that there is a failure. After step 400, it is determined whether or not the right parking lock release flag is OFF (step 405).

  If step 405 is affirmed, it means that the parking lock of the right rear wheel RR has not been released, so it is determined that the parking lock mechanism related to the right rear wheel RR has failed (step 410). On the other hand, if step 405 is negative, the right parking lock release flag should be ON and the left parking lock release flag should be OFF. In this case, the parking lock of the left rear wheel RL has not been released. It is. In this case, it is determined that the parking lock mechanism related to the left rear wheel RL has failed (step 415). In this way, it is also possible to specify the failure part.

  The present invention is not limited to the embodiment described above. For example, in the above-described embodiment, the parking lock is operated by the gear lever 11. However, for example, a button for canceling the execution of parking lock may be provided, and the button may be operated by pressing it, and may be operated by pressing it again to release it. In this case, a device that detects the operation of such a button (the button itself, a sensor, or the like) functions as a parking lock operation detection means. Further, the parking lock mechanism needs to be mechanically fixable or structured, but is not limited to the fixing structure by meshing the gear and the engaging member as described above.

  Furthermore, in the parking lock release embodiment described above, when the parking lock is released only for one of the wheels, the parking lock is released again by performing the control of the flowcharts of FIGS. 3 and 4 again. . However, when the parking lock is released for only one wheel, the hydraulic brake control is performed on the wheel for which the parking lock is released (both wheels are acceptable), and the wheels that are not immediately released from the parking lock (both The wheel release control may be retried. Then, the hydraulic brake control may be released when the parking lock release of the two wheels can be confirmed from the detection result of the lock state detection sensor 15a.

It is a lineblock diagram of vehicles provided with one embodiment of a parking lock device of the present invention. It is a flowchart of parking lock execution control. It is a flowchart (first half) of parking lock release control. It is a flowchart (second half) of parking lock release control. It is another example of the flowchart of parking lock release control.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... In-wheel motor, 3 ... Brake caliper, 4 ... Brake disc, 5 ... Brake pedal, 6 ... Master cylinder, 7 ... Actuator, 8 ... ECU, 9 ... Accelerator pedal, 10 ... Stroke sensor, 11 ... Gear lever, 12 ... position sensor, 13 ... inverter, 14 ... battery, 15 ... parking lock mechanism.

Claims (4)

A parking lock device for a vehicle provided with a drive mechanism capable of independently driving a pair of left and right wheels,
A hydraulic brake mechanism capable of independently braking or fixing the pair of left and right wheels independently of the operation of the driver;
Parking lock operation detecting means for detecting execution or release operation of the parking lock;
A parking lock mechanism that mechanically fixes the pair of left and right wheels independently when performing parking lock;
Lock state detecting means for detecting a mechanically fixed state of the left and right wheels by the parking lock mechanism;
Control that brakes or fixes at least one of the left and right wheels by the hydraulic brake mechanism based on the detection result of the lock state detection means when the parking lock operation detection means detects an execution or release operation of the parking lock. And a parking lock device.   When the parking lock operation detecting means detects the parking lock execution operation, the control means operates a hydraulic brake on at least a wheel on the side of the pair of the left and right wheels on which the parking lock execution is delayed. The parking lock device according to claim 1, wherein   When the parking lock release detecting operation is detected by the parking lock operation detecting means, the control means activates a hydraulic brake for at least one of the pair of left and right wheels on which the parking lock is released earlier. The parking lock device according to claim 1, wherein   The wheel rotation detection means for detecting the rotation of the wheel and the failure diagnosis means for making a failure diagnosis based on the detection results of the wheel rotation detection means and the lock state detection means. The parking lock device according to any one of?

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