JP2014189195A - Parking lock device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which: in a conventional parking lock mechanism, fitting of a claw to a parking gear is prevented by using hydraulic pressure corresponding to travel; however, the mechanism is complicated to lose engine output and lead to a reduction in fuel economy.SOLUTION: A parking lock device of an automatic transmission comprises a parking gear connected to a transmission shaft, a ball parking lock having the tip fittably-separably arranged in the parking gear, a parking lock cam for moving the tip to a position fitted to the parking gear by abutting on the ball parking lock by being displaced to a second position from a first position, a parking rod for moving the parking lock cam to the second position from the first position via a spring and a link mechanism for operating the parking rod, where the parking gear has a plate movable to an addendum from the tooth bottom.

Description

  The present invention relates to a parking lock device for an automatic transmission having a malfunction prevention function for preventing a lock state from being accidentally locked during traveling.

  A vehicle having an automatic transmission is equipped with a parking lock mechanism that locks the drive shaft so that the wheels do not rotate when the vehicle is stopped.

  The parking lock mechanism includes a parking gear connected to a transmission shaft immediately before the differential gear, an arm provided with a claw that fits into the parking gear, and the like. When the driver puts the gear operation lever into the parking position (hereinafter referred to as “P range”) when the vehicle stops, the arm moves and the pawl engages with the parking gear.

  When the pawl is engaged with the parking gear connected to the transmission shaft, the parking gear cannot rotate, and the vehicle does not move due to the gravity received by the vehicle when parking on the ramp or the external input to the vehicle .

  In such a parking lock mechanism, if the driver accidentally puts the gear operation lever into the P range during traveling, there is a concern that the transmission shaft suddenly stops or the claws break and abnormal noise is generated.

  Therefore, a parking lock prevention mechanism for preventing the pawl from engaging with the parking gear during traveling has been proposed. Patent Document 1 discloses a parking lock mechanism provided with a piston for fixing a parking arm having a pawl fitted to a parking gear with pressure oil corresponding to an engine output.

JP 61-115758 A

  The parking lock mechanism of Patent Document 1 generates a governor pressure by a hydraulic pressure adjusting device such as a regulator valve in accordance with a vehicle running condition such as an engine throttle opening, and locks the movement of the parking arm with a piston that operates with the hydraulic pressure. Therefore, the lock is not released unless the vehicle stops or falls below a predetermined speed.

  Therefore, reliable operation is guaranteed. However, since the mechanism is complicated and hydraulic pressure generated by engine output is used, there is a problem in that engine output is lost.

  The present invention is an invention conceived in view of the above-described problems, and provides a parking lock device that is a simple mechanism and does not accidentally lock the parking gear during traveling and does not lose engine output. It is.

More specifically, the parking lock device according to the present invention includes:
A parking gear coupled to the transmission shaft;
A pole parking lock, the tip of which is arranged to be able to be fitted and removed from the parking gear;
A parking lock cam that moves from a first position to a second position so as to abut on the pole parking lock and move the tip to a position that fits the parking gear;
A parking rod for moving the parking lock cam from the first position to the second position via a spring;
A link mechanism for operating the parking rod;
The parking gear is
It has the plate which can move from a tooth base to a tooth tip, It is characterized by the above-mentioned.

  Since the parking lock device according to the present invention has a plate that can move from the tooth bottom to the tooth tip in the parking gear, the plate moves to the tooth tip by centrifugal force during traveling. And even if it enters the P range during traveling and tries to move the tip of the pole parking lock to the position where it fits into the parking gear, it cannot be fitted because it is obstructed by the plate.

  Therefore, even when the vehicle is erroneously put in the P range during traveling, it is possible to reduce the hitting sound that the parking lock is engaged with and the wear of the parking gear and the like. In addition, since no hydraulic mechanism is used, the structure is simple and the fuel consumption is not reduced.

It is a figure which shows the structure of the parking lock apparatus which concerns on this invention. It is an enlarged view of a parking gear part. It is a figure which shows sectional drawing of a tooth root part. It is a figure which shows the other form of a plate.

  The parking lock device of the present invention will be described below with reference to the drawings. The following description exemplifies an embodiment of the present invention, and the present invention is not limited to the following description. That is, the following embodiments can be changed without departing from the gist of the present invention.

  FIG. 1 shows an outline of a parking lock device 1 according to the present invention. The parking lock device 1 includes a link mechanism 10 connected to a gear change lever 90, a parking rod 12 whose tip is displaced by the link mechanism 10, a spring 14, a parking lock cam 16, a pole parking lock 18, a parking gear. 20 is included.

  The gear change lever 90 is a lever for selecting a drive gear, and a D range for normal traveling is prepared. The gear change lever 90 is provided with at least a P range. A push-pull cable 10 a is connected to the lower end 90 a of the gear change lever 90. The push-pull cable 10a transmits the movement of the gear change lever 90 as a linear movement. The link mechanism 10 includes a gear change lever 90 and a push-pull cable 10a.

  A parking rod 12 is connected to the tip of the push-pull cable 10a. FIG. 2A is an arrow view from the direction A in FIG. The parking rod 12 linearly moves left and right on the paper surface by the push-pull cable 10a. The parking rod 12 is provided with a spring retainer 12a. The tip of the parking rod 12 is inserted into the through hole 16 a of the parking lock cam 16.

  The parking lock cam 16 is a cam having a conical surface 16c with the through hole 16a as an axis. The through hole 16 a is provided with one opening on the back surface 16 b of the parking lock cam 16. The diameter of the through hole 16a is larger than the diameter of the parking rod 12, and the parking lock cam 16 can move on the parking rod 12 almost without resistance.

  A spring 14 is disposed between the back surface 16b and the spring retainer 12a. Therefore, it can be said that the parking lock cam 16 is provided with the spring 14.

  The parking lock cam 16 and the parking rod 12 are disposed at a position where the conical surface 16 c faces the contact portion 18 b of the pole parking lock 18.

  The pole parking lock 18 is disposed at a position where the tip 18a can be fitted to and removed from the tooth root 20b of the parking gear 20. And it is pivotally supported at a pivot position 18c away from the tip 18a. The pole parking lock 18 is preferably arranged below the gravity with respect to the parking gear 20.

  This is because when the movement of the pole parking lock 18 can no longer be controlled, the vehicle can be kept running. If the tip 18a approaches the parking gear 20 from below gravity, it can be prevented that the parking gear 20 remains fitted when the movement of the pole parking lock 18 cannot be controlled.

  The contact portion 18b is provided below the tip 18a. As described above, the contact portion 18 b faces the conical surface 16 c of the parking lock cam 16. Therefore, when the conical surface 16c moves, the contact portion 18b is pushed upward in the gravity direction. That is, the parking lock cam 16 swings the pole parking lock 18.

  The parking gear 20 is a gear having a tooth tip 20a and a tooth root 20b, and is connected to a transmission shaft from the engine toward the wheel. Therefore, when the parking gear 20 is locked, the transmission shaft does not rotate and the drive wheels do not rotate.

  Referring to FIG. 2B, a plate 22 is disposed on the surface of the parking gear 20 for each tooth root 20b. The plate 22 is provided with a long hole 22a. A fixed projection 20d is provided from the root 20b of the parking gear 20 to the axis 20c. The fixed protrusion 20d has an elongated shape from the axis 20c of the parking gear 20 toward the circumference.

  The length of the elongated shape is narrower and shorter than the long hole 22 a of the plate 22. The long hole 22a of the plate 22 is inserted into the fixed protrusion 20d. That is, the plate 22 is movably disposed from the axis 20c side of the parking gear 20 toward the circumference (tooth tip 20a).

  Further, when the plate 22 moves toward the circumferential side, the tip 22b reaches the same circumference as the tooth tip 20a of the parking gear 20. Further, when the plate 22 moves toward the axis 20c, the tip 22b of the plate 22 moves back to the tooth bottom 20bb (see FIG. 2A).

  FIG. 3 shows a BB cross section of FIG. Referring to FIG. 3A, a holder plate 24 is fixed to the surface of the parking gear 20 on which the plate 22 is disposed so as to sandwich the fixing protrusion 20d. The plate 22 is movably held on the surface of the parking gear 20 by the holder plate 24.

  Further, the pole parking lock 18 has its tip 18a engaged with the parking gear 20, and when the tip 22b of the plate 22 moves to the circumference, it comes into contact with the tip 22b of the plate 22. Arranged.

  The operation of the parking lock device 1 having the above configuration will be described. Referring to FIG. 2A again, when the vehicle is traveling, the parking gear 20 is also rotated by the rotation of the transmission shaft. Due to the centrifugal force, all the plates 22 are moving toward the tooth tip 20a.

  When the vehicle stops and the driver operates the gear change lever 90 to enter the P range, the lower end 90a of the gear change lever 90 transmits the movement to the parking rod 12 via the link mechanism 10 (see FIG. 1). . The parking rod 12 is moved by the link mechanism 10 in the pressed direction (from the left to the right in FIG. 2A).

  As the parking rod 12 moves, the spring retainer 12a also moves. The spring retainer 12 a biases the parking lock cam 16 located at the first position via the spring 14. The biased parking lock cam 16 is displaced to the second position in the same direction as the parking rod 12. At this time, the conical surface 16 c of the parking lock cam 16 is displaced while abutting against the abutting portion 18 b of the pole parking lock 18.

  The contact portion 18b of the pole parking lock 18 ascends along the conical surface 16c of the parking lock cam 16. The pole parking lock 18 swings around the pivot position 18c as a pivot, and the tip 18a rises.

  Reference is again made to FIG. As shown in FIG. 3 (b), the abutting portion 18b, which is in a position where it does not fit with the tooth 20b of the parking gear 20, rises and engages with the tooth 20b while pushing up the plate 22 (FIG. 2 ( (See dotted line a)). By this fitting, the parking gear 20 is locked and the transmission shaft is also fixed. Therefore, the vehicle does not start while the vehicle is stopped, and safety is guaranteed.

  A case will be described in which the gear change lever 90 is erroneously put in the P range while the vehicle is traveling. Also in this case, the parking rod 12 moves, the parking lock cam 16 is displaced from the first position to the second position via the spring 14, and the tip 18 a of the pole parking lock 18 is engaged with the parking gear 20. Try to.

  However, referring to FIG. 3C, the parking gear 20 rotates at a high speed, and therefore the plate 22 is pressed against the tooth tip 20a side by centrifugal force. Therefore, the tip 18 a of the pole parking lock 18 cannot be fitted to the parking gear 20.

  The pole parking lock 18 is pushed up by the parking lock cam 16 biased by the spring 14 (see FIG. 2A). Therefore, if it cannot move to the parking gear 20 side, the urging force due to the movement of the parking rod 12 can be absorbed by the spring 14 contracting. That is, even if the plate 22 fixed by the centrifugal force is hindered from rising, the spring 14 contracts and does not rise any further. That is, the parking gear 20 is not forcibly engaged.

  In other words, in order to satisfy the above relationship, when the parking gear 20 rotates, the plate 22 causes the gravity and centrifugal force applied to the plate 22 to engage the tip 18a of the pole parking lock 18 with the parking gear 20. The mass is greater than the force applied.

  As described above, the parking lock device 1 according to the present invention avoids erroneous operation of the parking lock due to an erroneous operation by the gear change lever 90 during traveling of the vehicle by using a simple mechanism without using hydraulic pressure. A lock can be performed.

  The plate 22 used in the parking lock device 1 according to the present invention can be moved from the tooth bottom 20bb of the parking gear 20 to the tooth tip 20a and can be pressed against the tooth tip 20a by centrifugal force as shown in FIG. It is not limited to the structure shown in (b).

  For example, a structure as shown in FIG. 4 may be used. FIG. 4 shows a plate 22 provided with a through hole 22h. The tooth tip 20a is provided with a pivot 20p that penetrates the through hole 22h. Further, a protrusion 20s is provided so that the tip 22b of the plate 22 stops at the tooth tip 20a.

  Further, a projection 20t for limiting the movement of the plate 22 is also provided so as not to interfere with the adjacent plate 22. The plate 22 and the parking gear 20 having such a configuration may be used.

  Since the parking lock device according to the present invention is composed of only mechanical parts, if the parking gear can be attached to the transmission shaft that transmits the driving force to the driving wheels, the parking locking device has not only the automobile but also the driving wheels. Can be used in general.

DESCRIPTION OF SYMBOLS 1 Parking lock apparatus 10 Link mechanism 10a Push pull cable 12 Parking rod 12a Spring retainer 14 Spring 16 Parking lock cam 16a Through-hole 16b Back surface 16c Conical surface 18 Pole parking lock 18a Tip 18b Contact part 18c Pivoting position 20 Parking gear 20a Teeth Tip 20b tooth root 20bb root 20c shaft center 20d fixed projection 20p pivot shaft 20s, 20t projection 22 plate 22a long hole 22b (plate) tip 22h through hole 24 holder plate 90 gear change lever 90a lower end (gear change lever)

Claims (1)

A parking lock device for an automatic transmission,
A parking gear coupled to the transmission shaft;
A pole parking lock, the tip of which is arranged to be able to be fitted and removed from the parking gear;
A parking lock cam that moves from a first position to a second position so as to abut on the pole parking lock and move the tip to a position that fits the parking gear;
A parking rod for moving the parking lock cam from the first position to the second position via a spring;
A link mechanism for operating the parking rod;
The parking gear is
A parking lock device for an automatic transmission, comprising a plate movable from a tooth bottom to a tooth tip.