JP6714482B2 - Park lock device - Google Patents

Description

The present invention relates to a parking lock device.

A parking lock device for performing parking lock of a vehicle is known. Patent Document 1 discloses a hydraulically operated parking lock device for a vehicle that moves a park rod by a hydraulic actuator.

JP, 2014-80110, A

On a slope or the like, torque is applied from the drive wheels to the parking gear. When the park rod is moved to the parking lock release side in this state, a large frictional force is generated in the park rod by an amount corresponding to the applied torque. Therefore, the hydraulic actuator that moves the park rod is required to have a thrust force that exceeds its frictional force.

However, if the piston diameter of the hydraulic actuator is increased in order to secure the thrust, the piston volume increases, so that the total amount of oil required when releasing the parking lock also increases. When the required total amount of oil is large, an attempt to supply the required total amount of oil in a short time increases the load on the hydraulic pressure supply source, which is disadvantageous in energy saving. Therefore, a technique capable of suppressing the total amount of oil required when releasing the parking lock is desired.

The present invention has been made in view of the above problems, and provides a parking lock device capable of reducing the total amount of oil required for releasing the parking lock while exerting the force necessary for releasing the parking lock. With the goal.

A park lock device according to an aspect of the present invention includes a pressure receiving chamber, a first piston having a first pressure receiving surface in the pressure receiving chamber, a second piston having a second pressure receiving surface in the pressure receiving chamber, and the first pressure receiving surface. And a park rod that moves toward the parking lock release side by the hydraulic pressure acting on the second pressure receiving surface. When the oil amount in the pressure receiving chamber is less than a predetermined amount, the oil amount in the pressure receiving chamber increases. As the first pressure receiving surface and the second pressure receiving surface move in a predetermined direction, and when the amount of oil in the pressure receiving chamber becomes equal to or more than the predetermined amount, the movement of the second pressure receiving surface stops, while the pressure receiving chamber in the pressure receiving chamber moves. The first pressure receiving surface moves in the predetermined direction as the amount of oil increases.

According to this aspect, when the amount of oil is less than the predetermined amount, a strong force is required to release the parking lock, but since the hydraulic pressure applied to both the first pressure receiving surface and the second pressure receiving surface contributes to releasing the parking lock, You can exert the necessary force to unlock the park lock. Further, when the oil amount is equal to or more than the predetermined amount, it is sufficient to release the parking lock with a weak force. However, since the movement of the second pressure receiving surface is stopped to suppress the increase in the capacity of the pressure receiving chamber, the total oil amount required when releasing the parking lock is reduced. It can be reduced.

It is FIG. 1 of the schematic block diagram of a park module. It is FIG. 2 of the schematic block diagram of a park module. It is FIG. 1 of operation|movement explanatory drawing of a park module. It is FIG. 2 of operation|movement explanatory drawing of a park module. It is FIG. 3 of operation|movement explanatory drawing of a park module.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 and 2 are schematic configuration diagrams of the park module 1. In FIG. 1, the park module 1 is shown in the park lock state. In FIG. 2, the park module 1 is shown in the park lock released state.

The park module 1 is a park lock device and is provided in a vehicle together with a transmission to mechanically lock the output shaft of the transmission. The park module 1 includes a parking gear 2, a parking pole 3, a park rod 4, a cam 5, a sleeve 6, a link lever 7, a park actuator 8, a lock mechanism 9, and a hydraulic circuit 10.

The parking gear 2 is fixed to the output shaft of the transmission and rotates or stops together with the output shaft. A parking pole 3 is engaged with the parking gear 2.

The parking pole 3 swings according to the movement of the park rod 4. When the parking pole 3 swings, the engagement state between the parking gear 2 and the parking pole 3 is changed.

As shown in FIG. 1, when the parking gear 2 and the parking pole 3 are engaged, the parking gear 2 is mechanically locked and the output shaft is also locked. As a result, the park module 1 enters the park lock state and the movement of the vehicle is restricted.

As shown in FIG. 2, when the parking gear 2 and the parking pole 3 are disengaged, the parking gear 2 and the output shaft are unlocked, and the parking gear 2 and the output shaft are rotatable. As a result, the park module 1 is placed in the parking lock released state, and the movement restriction of the vehicle is released.

The park rod 4 is moved to the park lock position shown in FIG. 1 and the non-park lock position shown in FIG. 2 by the park actuator 8.

A cam 5 is attached to one end of the park rod 4. The cam 5 contacts the parking pole 3 and swings the parking pole 3 according to the movement of the park rod 4. The cam 5 engages the parking gear 2 and the parking pole 3 when the park rod 4 is in the parking lock position shown in FIG. The cam 5 releases the engagement between the parking gear 2 and the parking pole 3 when the park rod 4 is in the non-parking position shown in FIG.

The cam 5 has a first tapered portion 5a and a second tapered portion 5b. The first tapered portion 5a contacts the parking pole 3 when the park rod 4 is in the parking lock position shown in FIG. The second taper portion 5b is connected to the first taper portion 5a from one end side of the park rod 4. Both the first taper portion 5a and the second taper portion 5b are gradually reduced in diameter from the other end side to the one end side of the park rod 4. The taper angle of the second taper portion 5b is set smaller than the taper angle of the first taper portion 5a.

The sleeve 6 is provided on the opposite side of the parking rod 3 with respect to the park rod 4. The sleeve 6 is immovably provided as a contact member that holds the contact state between the parking pole 3 and the cam 5 or the park rod 4 by contacting the cam 5 or the park rod 4 from the side opposite to the parking pole 3.

One end of a link lever 7 is connected to the other end of the park rod 4. The link lever 7 transmits the force of the park actuator 8 to the park rod 4. A rotary shaft is provided at an intermediate portion of the link lever 7. The link lever 7 rotates about the rotation axis to move the park rod 4 in the parking lock releasing direction when the park actuator 8 extends, and moves the park rod 4 in the parking lock direction when the park actuator 8 shortens. ..

The park actuator 8 drives the park rod 4. The park actuator 8 drives the park rod 4 to the parking lock position shown in FIG. 1 when the parking range is selected, and the park rod 4 is shown in FIG. 2 when a range other than the parking range is selected. Drive to a non-parking position. Hereinafter, the parking range will be referred to as a P range, and the ranges other than the parking range will be referred to as a notP range.

Specifically, the park actuator 8 is composed of a hydraulic cylinder, and includes a cylinder 81, a first piston 82, a second piston 83, a pressure receiving chamber 84, a first spring 85, and a second spring 86.

The cylinder 81 houses the first piston 82 and the second piston 83. The cylinder 81 is a stepped cylinder and has a step portion 81a, a reduced diameter portion 81b, and an enlarged diameter portion 81c. The stepped portion 81a expands the diameter of the cylinder 81 on the side where the pressure receiving chamber 84 is provided than on the opposite side. The diameter-reduced portion 81b is the smaller diameter portion of the two cylinder portions connected to the stepped portion 81a, and the diameter-increased portion 81c is the larger diameter portion of the two cylinder portions connected to the stepped portion 81a. is there. The bottom of the cylinder 81 is connected to the enlarged diameter portion 81c from the side opposite to the stepped portion 81a.

The second piston 83 is housed in the expanded diameter portion 81c and is provided slidably with respect to the expanded diameter portion 81c. The second piston 83 can be provided with a seal ring that seals the clearance between the second piston 83 and the expanded diameter portion 81c.

The second piston 83 has a second pressure receiving surface 83 a facing the pressure receiving chamber 84. In this manner, the second piston 83 is configured to have the second pressure receiving surface 83a inside the pressure receiving chamber 84. The second piston 83 has a cylindrical shape, and the first piston 82 is inserted into the second piston 83.

The first piston 82 has a piston portion 821, a flange portion 822, and a rod portion 823. The first piston 82 is composed of a single member. The first piston 82 may be composed of a combination of a plurality of members.

The piston portion 821 is housed in the second piston 83 and is provided slidably with respect to the second piston 83. The axial length of the piston portion 821 is set to be the same as the axial length of the second piston 83.

The piston portion 821 has a first pressure receiving surface 82a facing the pressure receiving chamber 84. In this manner, the first piston 82 is configured to have the first pressure receiving surface 82a inside the pressure receiving chamber 84. The piston portion 821 can be provided with a seal ring that seals the clearance between the piston portion 821 and the second piston 83.

The flange portion 822 is connected to the piston portion 821 from the side opposite to the pressure receiving chamber 84 side. The outer diameter of the flange portion 822 is set to be larger than the outer diameter of the piston portion 821 and smaller than the inner diameter of the reduced diameter portion 81b.

The rod portion 823 is connected to the flange portion 822 from the side opposite to the pressure receiving chamber 84 side. The outer diameter of the rod portion 823 is set smaller than the outer diameter of the flange portion 822. The rod portion 823 is provided so as to project from the cylinder 81 to the outside. The other end of the link lever 7 is connected to the portion of the rod portion 823 that projects outward from the cylinder 81 in the park lock state shown in FIG.

The rod portion 823 is provided with an engaging portion 82b. The engaging portion 82b is provided on a portion of the rod portion 823 that projects outward from the cylinder 81 in the park lock released state shown in FIG. The lock mechanism 9 is engaged with the engaging portion 82b in the parking lock released state shown in FIG. In other words, the locking mechanism 9 engages with the engaging portion 82b when the park rod 4 is located in the non-parking position shown in FIG.

The pressure receiving chamber 84 is formed by the cylinder 81, the first piston 82, and the second piston 83. Even in the park lock state shown in FIG. 1, the pressure receiving chamber 84 is formed with a slight gap between the bottom surface of the cylinder 81 and the first piston 82 and the second piston 83. In order to form the pressure receiving chamber 84 in this way, for example, a stepped portion that prevents the second piston 83 from being seated on the bottom surface of the cylinder 81 can be provided in the cylinder 81.

The first spring 85 is a return spring of the first piston 82 and biases the first piston 82 toward the pressure receiving chamber 84 side. The second spring 86 is a return spring of the second piston 83, and biases the second piston 83 toward the pressure receiving chamber 84 side.

The lock mechanism 9 engages with the engaging portion 82b in the parking lock released state shown in FIG. As a result, the first piston 82 is locked at the parking lock release position, and the movement of the park rod 4 is stopped. As a result, the park module 1 is locked in the park lock released state. The lock mechanism 9 is configured to include an electronically controllable actuator.

The hydraulic circuit 10 includes a hydraulic pressure supply unit 11, a control oil passage 12, a solenoid valve 13, and an oil storage unit 14.

The hydraulic pressure supply unit 11 supplies hydraulic pressure to the pressure receiving chamber 84. Specifically, the hydraulic pressure supply unit 11 is configured to include an oil pump and a line pressure adjusting valve that generates and adjusts the line pressure PL based on the oil supplied by the oil pump, and supplies the line pressure PL to the pressure receiving chamber 84. Supply. The line pressure PL constitutes the control hydraulic pressure of the park actuator 8.

The control oil passage 12 connects the hydraulic pressure supply unit 11 and the pressure receiving chamber 84. The control oil passage 12 penetrates the bottom of the cylinder 81 and opens into the cylinder 81. A solenoid valve 13 is provided in the control oil passage 12. The solenoid valve 13 switches the oil distribution path between a communication state in which the control oil passage 12 is in communication and a cutoff state in which the control oil passage 12 is cut off. As shown in FIG. 2, the solenoid valve 13 is in a communication state and is in a supply state in which oil can be supplied to the pressure receiving chamber 84 via the control oil passage 12.

As shown in FIG. 1, when the solenoid valve 13 is closed, the control oil passage 12 is cut off. In this case, the solenoid valve 13 further connects the pressure receiving chamber 84 and the oil reservoir 14. For this reason, the solenoid valve 13 is in a shut-off state and is in a drain state in which oil can be drained from the pressure receiving chamber 84. The oil reservoir 14 stores the oil drained from the park actuator 8 or the like.

The park module 1 is controlled by the controller. The controller is, for example, a transmission controller that controls the transmission, and when the selected range is changed between the P range and the notP range, the park module 1 is controlled to perform the parking lock and the parking lock release. ..

At this time, the lock mechanism 9 locks and unlocks the first piston 82 under the control of the controller. Further, the solenoid valve 13 switches the oil distribution path under the control of the controller.

3 to 5 are operation explanatory views of the park module 1. 3 to 5, the states of the park module 1 are shown as states S1 to S6. 3 to 5, a park module 1'is also shown as a comparative example. The park module 1'includes a general park actuator 8'where a single pressure receiving chamber 84' is formed by a cylinder 81' and a single piston 82'. In the park actuator 8 ′, the second spring 86 is used as the return spring of the piston 82 ′ and therefore does not have the first spring 85.

In the state S1, it is in the park lock state, and the first piston 82 and the second piston 83 are located at the park lock position. The same applies to the piston 82'. The solenoid valve 13 is in the drain state. The lock mechanism 9 is unlocked.

When the selected range is changed from the P range to the notP range in the state S1, the solenoid valve 13 is in the communication state and is in the supply state, and the state shifts to the state S2. A state S2 is a state when the parking lock is released and the amount of oil in the pressure receiving chamber 84 is a predetermined amount A described later. Specifically, the state transitions from the state S1 to the state S2 as follows.

When the amount of oil in the pressure receiving chamber 84 is less than the predetermined amount A, the hydraulic pressure of the pressure receiving chamber 84 acts on the first pressure receiving surface 82a and the second pressure receiving surface 83a. Therefore, as the amount of oil in the pressure receiving chamber 84 increases, both the first pressure receiving surface 82a and the second pressure receiving surface 83a move in the parking lock releasing direction. Further, in response to this, the park rod 4 moves to the parking lock release side.

The parking lock releasing direction for the first piston 82 and the second piston 83 corresponds to a predetermined direction. In this embodiment, the parking lock releasing direction as the predetermined direction is set to the opposite direction to the parking lock releasing direction for the park rod 4 by the link lever 7.

When the amount of oil in the pressure receiving chamber 84 reaches the predetermined amount A, the second piston 83 comes into contact with the step portion 81a and stops. The first piston 82 can continue to move. Therefore, when the amount of oil in the pressure receiving chamber 84 becomes equal to or larger than the predetermined amount A, the movement of the second pressure receiving surface 83a stops, while the first pressure receiving face 82a releases the parking lock as the amount of oil in the pressure receiving chamber 84 increases. Move in the direction.

As described above, in the park module 1, when the amount of oil in the pressure receiving chamber 84 is less than the predetermined amount A, the first piston 82 and the second piston 83 generate thrust for releasing the parking lock. When the amount of oil in the pressure receiving chamber 84 is less than the predetermined amount A, the cam 5 comes into contact with the parking pole 3 and the sleeve 6 at the first tapered portion 5a, and as a result, the operation region of the park actuator 8 has a large thrust force for releasing the parking lock. Is a necessary operating area.

In the park module 1, when the amount of oil in the pressure receiving chamber 84 becomes equal to or greater than the predetermined amount A, the first piston 82 generates thrust for releasing the parking lock. When the amount of oil in the pressure receiving chamber 84 becomes equal to or larger than the predetermined amount A, the cam 5 does not come into contact with the parking pole 3 and the sleeve 6 at the first taper portion 5a and the parking lock is released. This is because a large thrust force is not required for releasing the parking lock, which is an operating region.

The predetermined amount A is a value for defining whether or not a large thrust force is required to release the parking lock in the operating region of the park actuator 8, and can be set in advance by experiments or the like. By limiting the number of pistons that generate thrust in this way, the amount of oil required to operate the park actuator 8 is reduced. In the park module 1', the piston 82' continues to move in the parking lock releasing direction as the amount of oil in the pressure receiving chamber 84' increases.

The state S3 shows a state in which the first piston 82 is located at the parking lock releasing position and the parking lock is released. The lock mechanism 9 locks the first piston 82 when the park module 1 is in the park lock released state. As a result, the state S3 shifts to the state S4, and the first piston 82 is locked after the parking lock is released. In the park module 1 ′, the piston 82 ′ is locked by the lock mechanism 9.

When the lock mechanism 9 locks the first piston 82, it is not necessary to supply oil to the pressure receiving chamber 84 to maintain the parking lock released state. For this reason, the solenoid valve 13 is turned off and put in the drain state. As a result, the state S4 shifts to the state S5.

As shown in state S5, when the solenoid valve 13 is in the drain state, the second piston 83 is in a direction opposite to the parking lock releasing direction as the predetermined direction, that is, the parking lock direction for the first piston 82 and the second piston 83. Move to.

Even if the second piston 83 moves in this manner, the lock mechanism 9 locks the first piston 82, so that the parking lock released state is maintained. By moving the second piston 83 in this way, the volume of the pressure receiving chamber 84 is reduced, and the amount of oil that must be discharged from the pressure receiving chamber 84 when performing parking lock is reduced. In the park module 1', even if the solenoid valve 13 is in the drain state, the volume inside the pressure receiving chamber 84' remains unchanged.

When the selected range becomes the P range, the lock mechanism 9 unlocks the first piston 82. As a result, the state S5 shifts to the state S6. In the state S6, the first piston 82 moves in the parking lock direction, and accordingly, the park rod 4 moves to the parking lock side, so that parking lock is performed. In the park module 1′, when the lock mechanism 9 releases the lock, the piston 82′ moves in the parking lock direction to perform parking lock.

Next, the main effects of this embodiment will be described.

The park module 1 has a pressure receiving chamber 84, a first piston 82, a second piston 83, and a park rod 4. In the park module 1, when the amount of oil in the pressure receiving chamber 84 is less than the predetermined amount A, as the amount of oil in the pressure receiving chamber 84 increases, the first pressure receiving surface 82a and the second pressure receiving surface 83a move in the park direction as the predetermined direction. Move in the unlocking direction. When the amount of oil in the pressure receiving chamber 84 becomes equal to or larger than the predetermined amount A, the movement of the second pressure receiving surface 83a stops, while the first pressure receiving face 82a moves in the predetermined direction as the amount of oil in the pressure receiving chamber 84 increases. Move in the direction to release the park lock.

With such a configuration, when the amount of oil is less than the predetermined amount A, a strong force is required to release the parking lock, but the hydraulic pressure applied to both the first pressure receiving surface 82a and the second pressure receiving surface 83a is released. Since it contributes to, it can exert the power necessary for releasing the parking lock. Further, when the oil amount is equal to or larger than the predetermined amount A, the parking lock release can be performed with a weak force, but the movement of the second pressure receiving surface 83a is stopped and the capacity increase of the pressure receiving chamber 84 is suppressed. The amount of oil can be reduced (effect corresponding to claim 1).

The park module 1 has a lock mechanism 9. In the park module 1, after releasing the parking lock, the lock mechanism 9 locks the first piston 82, and the second piston 83 moves in the direction opposite to the unlocking direction as the predetermined direction.

With such a configuration, the amount of oil that must be discharged from the pressure receiving chamber 84 when performing parking lock can be reduced, so that parking lock can be performed quickly (effect corresponding to claim 2).

Although the embodiment of the present invention has been described above, the above embodiment merely shows a part of the application example of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

In the above-described embodiment, the case where the parking lock releasing direction as the predetermined direction is opposite to the parking lock releasing direction for the park rod 4 has been described. However, the parking lock releasing direction as the predetermined direction may be the same as the parking lock releasing direction for the park rod 4.

1 Park module (park lock device)
4 park rod 5 cam 5a first tapered portion 5b second tapered portion 8 park actuator 81 cylinder 81a stepped portion 82 first piston 82a first pressure receiving surface 83 second piston 83a second pressure receiving surface 84 pressure receiving chamber 9 locking mechanism

Claims (2)

Pressure chamber,
A first piston having a first pressure receiving surface in the pressure receiving chamber;
A second piston having a second pressure receiving surface in the pressure receiving chamber;
And a park rod that moves toward the parking lock release side when hydraulic pressure acts on the first pressure receiving surface and the second pressure receiving surface.
When the oil amount in the pressure receiving chamber is less than a predetermined amount, the first pressure receiving surface and the second pressure receiving surface move in a predetermined direction as the oil amount in the pressure receiving chamber increases,
When the amount of oil in the pressure receiving chamber becomes equal to or more than the predetermined amount, the movement of the second pressure receiving surface stops, while the first pressure receiving face moves in the predetermined direction as the amount of oil in the pressure receiving chamber increases.
Park lock device characterized in that. The park lock device according to claim 1, wherein
A lock mechanism for locking the first piston at the park lock release position,
After releasing the park lock, the lock mechanism locks the first piston, and the second piston moves in a direction opposite to the predetermined direction,
Park lock device characterized in that.

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