JP2007326438A - Parking structure of automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure a clearance required between a distal end face of an engaging pawl and a tooth end of a parking gear at the time of unlocking a parking lock in a parking structure projecting a center of the distal end face of the engaging pawl. <P>SOLUTION: A difference 4c in level is formed between a rod abutting face 4b and a support abutting face 4a in a parking pole 4. The rod abutting face 4b is arranged on a lower side of the support abutting face 4a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a parking structure for an automatic transmission, and more particularly to a technique for ensuring a clearance between components.

  In the automatic transmission, when the driver operates the select lever to the P range (stop position), the output shaft is obtained by engaging the engagement pawl of the parking pole with the parking gear fixed to the output shaft of the transmission. A parking structure is provided to mechanically lock the vehicle (parking lock) so that the vehicle does not move.

  In such a parking structure, if the parking lock is attempted when the vehicle is not completely stopped, the engaging claws repeatedly collide with the teeth of the rotating parking gear, and the corners of the engaging claws are worn or missing. There is a possibility.

Therefore, in the parking structure described in Patent Document 1, when the parking lock is performed when the tip end surface of the engaging pawl of the parking pole is raised in an arc shape and the vehicle is not completely stopped, the arcuate surface is By first colliding with the teeth of the parking gear, the corners of the engaging claws are prevented from being worn or chipped.
Japanese Utility Model Publication No. 6-49849

  However, if the front end surface of the engaging claw is raised in an arc shape as in the above-described prior art, the distance between the front end surface of the engaging claw and the tooth tip of the parking gear is shortened in the parking lock release state, which is necessary between the two. It becomes difficult to ensure the clearance.

  The present invention has been made in view of such technical problems of the prior art. In the parking structure in which the center of the front end surface of the engaging claw is raised as in the above prior art, the engaging claw is released when the parking lock is released. The purpose is to ensure the required clearance between the tip surface and the tooth tip of the parking gear.

  The parking structure according to the present invention has a parking gear fixed to the output shaft of the automatic transmission and an engaging claw that protrudes toward the parking gear at the center of the front end surface, and is separated from the output shaft. A rod contact surface formed on a lower surface of the pole base end opposite to the support shaft of the parking pole, and the rod contact surface and the support shaft. A parking pole having a support abutting surface formed between and a cam portion, and a direction in which the engaging claw engages with a tooth groove of the parking gear by abutting the cam portion against the rod abutting surface. The parking rod that locks the parking pole by rotating the parking pole and the parking pawl contact with the support contact surface of the parking pole when the parking lock is released. Comprises a support member for holding the release position away from the tooth tip, the. And a level | step difference is provided between a rod contact surface and a support contact surface, and a rod contact surface is arrange | positioned below a support contact surface.

  According to the present invention, since the rotation angle of the parking pole when the parking pole is moved and held to the release position is increased as compared with the conventional structure, when the parking pole is held at the release position, the tip of the engaging claw The clearance can be ensured by separating the surface from the tooth tip of the parking gear. In addition, the rotation angle of the parking pole when the rod contact surface comes into contact with the cam portion and the parking pole rotates in the engaging direction increases, and the required engagement length between the engaging claw and the parking gear is increased. Can be secured.

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

  1 to 3 show a parking structure according to the present invention. FIG. 1 is a partial sectional view of a portion where the parking structure is provided, FIG. 2 is a sectional view taken along line XX of FIG. It is YY sectional drawing of FIG.

  The parking structure includes a parking gear 2 that is fixed to the output shaft 1 of the transmission, a parking pole 4 that has an engaging claw 3 that engages with the parking gear 2, a parking rod 5 that extends in a direction substantially orthogonal to the parking pole 4, A joint portion 6 fitted outside the parking rod 5 and a rod plate 7 that supports the joint portion 6 so as to tilt and rotate are provided. In the figure, 8 is an input shaft of the transmission, and an output shaft of the engine is connected via a torque converter (not shown).

  The parking pole 4 is rotatably supported by a support shaft 9 extending parallel to the output shaft 1 at a position separated from the output shaft 1, and a torsion spring 10 is wound around the outer periphery of the support shaft 9. In a compressed state, the torsion spring 10 has one end locked to the inner wall of the recess 11 formed in the transmission case, and the other end locked to the upper edge of the parking pole 4. 4 is urged in the release direction (clockwise direction in FIG. 1).

  An engaging claw 3 extending toward the parking gear 2 is formed on the lower surface on the front end side of the parking pole 4. When the parking pole 4 rotates in the engagement direction (counterclockwise direction in FIG. 1) against the urging force of the torsion spring 10, the engagement claw 3 enters the tooth groove of the parking gear 2 and engages. The output shaft 1 is mechanically locked (parking lock).

  As shown in FIG. 4, the front end surface 3a of the engaging claw 3 has an arcuate surface that gently rises toward the parking gear 2, and the engaging claw is engaged when the parking gear 2 is rotating. 3 approaches the parking gear 2 and the engaging claw 3 collides with the teeth of the parking gear 2, this arcuate surface first collides with the tooth tip of the parking gear 2, and the corner of the engaging claw 3 Prevent wear and chipping.

  A support member 12 is fixed to the transmission case by a bolt below the base end side of the parking pole 4. When the parking lock is released, the support member 12 abuts the parking pole 4 biased in the releasing direction by the torsion spring 10 from the lower side and holds the parking pole 4 in the releasing position shown in FIG. 4 has a support concave surface 12b that supports the parking rod 5 from below at a position facing the lower surface of the base end of 4.

  As shown in FIGS. 2 and 3, a cam portion 13 whose diameter gradually increases from the position adjacent to the support member 12 toward the rod tip side is formed at the tip of the parking rod 5. A diameter portion 14 is formed. The cam portion 13 functions as a cam surface that comes into contact with the lower surface of the base end of the parking pole 4 and the support concave surface 12b of the support member 12 and lifts the base end of the parking pole 4 when the parking lock is performed. It functions as a support member that supports the base end of the parking pole 4.

  As shown in FIG. 5, the support contact surface 4 a that contacts the support end surface 12 a of the support member 12 enters the inside of the parking pole 4 more than the conventional structure shown by the broken line, and the rod that faces the parking rod 5. The contact surface 4b protrudes outward from the lower surface of the parking pole 4 rather than the conventional structure shown by the broken line. That is, in the structure shown in the figure, a step 4c is provided between the contact surfaces 4a and 4b to connect the contact surfaces 4a and 4b, so that the rod contact surface 4b is positioned below the support contact surface 4a. It is arranged.

  Further, the diameter of the portion (hereinafter referred to as the reduced diameter portion) 5a facing the rod contact surface 4b of the parking rod 5 is such that the outer peripheral surface of the parking rod 5 and the rod contact surface 4b when the select lever is outside the P range. As shown in FIG. 6, the diameter of the portion adjacent to the reduced diameter portion 5a, that is, the diameter of the proximal end side of the cam portion 13, the center of the parking rod 5 is secured. It is smaller than the diameter of the part. A broken line in the figure is a line corresponding to the diameter of an adjacent part. Since the parking rod 5 is displaced in the axial direction in accordance with the position of the select lever, the diameter-reduced portion 5a is formed as a groove that is wide in the axial direction of the parking rod 5 at a position facing the rod contact surface 4b of the parking rod 5. The parking rod 5 is formed over the entire outer periphery.

  On the other hand, the base end side of the parking rod 5 is a base end side shaft portion 15 having a smaller diameter, and the parking rod 5 is inserted into the support hole 16 of the joint portion 6 through the base end side shaft portion 15. And is slidably supported in the axial direction.

  Further, the rod base end side end surface of the joint portion 6 is used as one seating surface, and the flange portion 35 fixed to the base end portion of the parking rod 5 is used as the other seating surface. The rod spring 21 is interposed between the flange portion 35 and the flange portion 35 in a compressed state, and the joint portion 6 is pressed against a joint receiving portion 30 formed in the axial direction of the parking rod 5 by the urging force of the rod spring 21. ing.

  The base portion 23 extending downward from the joint portion 6 is supported so as to be tiltable and rotatable with respect to the rod plate 7. A projecting portion 24 extending laterally from the base end portion 23 is integrally formed at the lower end of the base portion 23 so that the joint portion 6 does not come out of the rod plate 7.

  As shown in FIG. 2, the rod plate 7 is fixed to a rotating shaft 25 that rotates in response to a driver's select lever operation. When the rotary shaft 25 rotates in response to the driver's operation of the select lever, the rod plate 7 rotates to an angular position corresponding to the position of the select lever (each range of L, D, N, R, and P). A plurality of valleys 26 are formed on the outer edge of the rod plate 7 corresponding to the position of the select lever, and when the holding pins 28 urged by the detent springs 27 are fitted into the valleys 26, the rod plate 7 is It is held at an angular position corresponding to the position of the select lever.

  Next, the operation of the parking structure will be described.

  When the driver operates the select lever from a range other than the P range to the P range (stop position), the rod plate 7 rotates clockwise in FIG. 2 about the rotation shaft 25 and corresponds to the P range by the detent spring 27. Held at the angular position. At this time, the joint portion 6 moves upward in FIG. 2 together with the parking rod 5 while being pressed against the joint receiving portion 30. As a result, the cam portion 13 provided at the distal end of the parking rod 5 enters between the lower surface on the proximal end side of the parking pole 4 and the support concave surface of the support member 12 and lifts the proximal end of the parking pole 4. The parking pole 4 rotates in the engaging direction (counterclockwise in FIG. 1) against the biasing force of the torsion spring 10, and engages the engaging claw 3 formed at the tip with the tooth groove of the parking gear 2. The output shaft 1 is locked so as not to rotate.

  When the engaging claw 3 collides with the teeth of the parking gear 2 and cannot be engaged, the parking pawl 4 is returned in the releasing direction (clockwise in FIG. 1), and a waiting operation for waiting until the engaging pawl 3 becomes engageable. Do.

  In the parking structure, in order to prevent wear and chipping of the corners of the engaging claw 3 due to repeated collision between the engaging claw 3 of the parking pole 4 and the teeth of the parking gear 2, the front end surface 3a of the engaging claw 3 is prevented. Is an arcuate surface that protrudes toward the parking gear 2 (see FIG. 4), and the engagement claw 3 and the tooth tip of the parking gear 2 come closer to each other by the height of the protruding end surface 3a.

  However, in the parking structure described above, the step 4c is provided between the support contact surface 4a and the rod contact surface 4b, thereby disposing the rod contact surface 4b below the support contact surface 4a (FIG. 4). 5), the parking pole 4 is moved to the release position, and the rotation angle of the parking pole 4 when held by the support member 12 is increased as compared with the conventional structure, and the front end surface 3a of the engaging claw 3 is parked. The clearance can be ensured by separating from the tooth tip of the gear 2.

  When the distal end surface 3a of the engagement claw 3 is an arcuate surface, the engagement claw 3 can be secured by an amount corresponding to the height of the arcuate surface in order to ensure a meshing length equivalent to a structure that does not employ the arcuate surface. Needs to be inserted deeper into the tooth groove of the parking gear 2, but since the rod contact surface 4b is disposed below the support contact surface 4a, the rod contact surface 4b contacts the cam portion 13. The rotation angle of the parking pole 4 when the parking pole 4 rotates in the engaging direction increases, and the required meshing length can be ensured.

  On the other hand, a decrease in the clearance between the rod contact surface 4b and the parking rod 5 due to the rod contact surface 4b being disposed below the support contact surface 4a is a reduced diameter of the parking rod 5 facing the rod contact surface 4b. This is solved by making the diameter of the part 5a smaller than the diameter of the part adjacent to the part 5a (see FIG. 6). As a result, the clearance required between the rod contact surface 4b and the parking rod can be secured even in the R range where the rod contact surface 4b and the parking rod 5 are closest to each other in the range other than the P range. 5 can be prevented from interfering.

  As mentioned above, although embodiment of this invention was described, the said embodiment only showed an example of the structure to which this invention was applied, and is not the meaning which limits the application range of this invention to the said structure. The above configuration can be modified without departing from the gist of the present invention, and these modified examples are of course included in the technical scope of the present invention.

It is a fragmentary sectional view of an automatic transmission provided with the parking structure concerning the present invention. It is sectional drawing which shows the XX cross section of FIG. It is sectional drawing which shows the YY cross section of FIG. It is a figure for demonstrating the structure of a parking pole. It is a figure for demonstrating the detailed structure of the base end side of a parking pole. It is a figure for demonstrating the detailed structure of the front end side of a parking rod.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Output shaft 2 Parking gear 3 Engagement claw 4 Parking pole 4a Support contact surface 4b Rod contact surface 4c Step 5 Parking rod 5a The part (diameter-reduced part) which opposes a rod contact surface
9 Support shaft 12 Support member 13 Cam part

Claims (2)

A parking gear fixed to the output shaft of the automatic transmission;
The center of the front end surface has an engaging claw that protrudes toward the parking gear on the pole front end side, and is rotatably supported by a support shaft that is spaced apart from the output shaft. A parking pole having a rod contact surface formed on the lower surface of the pole base end opposite to the support shaft and a support contact surface formed between the rod contact surface and the support shaft;
It has a cam part, and by making this cam part contact the rod contact surface, the parking pawl is rotated in the direction in which the engaging claw engages with the tooth groove of the parking gear to perform parking lock. A parking rod,
A support member that abuts the support contact surface of the parking pole when the parking lock is released, and holds the parking pole in a release position in which a tip surface of the engagement claw is separated from a tooth tip of the parking gear;
A parking structure for an automatic transmission, characterized in that a step is provided between the rod contact surface and the support contact surface, and the rod contact surface is disposed below the support contact surface.   2. The parking structure for an automatic transmission according to claim 1, wherein a diameter of a part of the parking rod facing the rod contact surface is smaller than a diameter of a part adjacent to the part.

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