JP2008064179A - Parking structure of transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parking structure of a transmission, which reliably maintains the stopped condition of a vehicle. <P>SOLUTION: The parking structure of the transmission comprises: an output shaft (16) which is rotatably supported by a housing (56) via a bearing (60) while the output of the transmission is transmitted thereto; a bearing fixing member (62) for fixing the bearing to the housing; a parking gear (74) provided on the bearing fixing member; a cover member (88) connected to the bearing fixing member to turnably hold the parking gear; a shift device (44) for changing the gear in the transmission; a synchronizing device (98) which is arranged in a vicinity of the parking gear on the output shaft and engaged with the parking gear to immobilize the output shaft if the parking position is selected by the shift device; and turn permitting means (66, 80, 84, 86, 90) for turning the parking gear by a predetermined quantity with respect to the bearing fixing member when the synchronizing device is engaged with the parking gear. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a parking structure for a transmission, and more particularly, to a parking structure for a transmission that can maintain a stopped state of a vehicle.

This type of parking structure is a safety mechanism arranged separately from the center brake.
Specifically, a parking gear is provided on the countershaft of the transmission, and when the parking position is selected by the shift device, the swinging parking pole meshes with the parking gear to make the countershaft unrotatable. (For example, refer to Patent Document 1). As a result, even if the driver forgets to put on the center brake, the stop state of the vehicle can be maintained within the allowable weight range.
JP 2001-280495 A

By the way, in the above prior art, since the parking gear is provided on the countershaft, it is necessary to extend the countershaft, and the transmission needs a space for providing the parking pole and the parking gear separately. There's a problem.
It should also be noted that the mechanism for swinging the parking pole exists separately from the speed change mechanism for operating the drive gear. This is because an increase in the operating mechanism and an increase in the number of parts hinder the simplification of the structure.

Furthermore, although the above-mentioned conventional technique is a one-way clutch mechanism in which the parking pawl meshes with the parking gear, it should be noted that the engagement between the parking pawl and the parking gear becomes difficult depending on the parking gear stop position. I must.
The present invention has been made in view of such problems, and an object of the present invention is to provide a parking structure for a transmission that can reliably maintain a stopped state of a vehicle.

  In order to achieve the above object, in the parking structure of the transmission according to claim 1, the output of the transmission is transmitted, the output shaft is rotatably supported by the housing via the bearing, and the bearing is fixed to the housing. A bearing fixing member, a parking gear provided on the bearing fixing member, a cover member that pivotably holds the parking gear and is connected to the bearing fixing member, a shift device that shifts a gear in the transmission, and an output When a parking position is selected by the shift device on the shaft and close to the parking gear, a synchronizing device that meshes with the parking gear and makes the output shaft unrotatable, and the synchronizing device and the parking gear It is characterized by comprising a rotation permitting means for allowing the parking gear to rotate a predetermined amount with respect to the bearing fixing member when meshing.

  According to a second aspect of the present invention, the rotation permitting means is formed on the bearing fixing member, and is formed toward the shaft center at the bulging portion fitted inside the parking gear and the outer peripheral edge of the bulging portion. A notch part, a protrusion formed in the parking gear and projecting into the notch part, and disposed between the notch part and the projecting part, and rotates the parking gear by a predetermined amount with respect to the bearing fixing member. And an elastic member.

  According to a third aspect of the present invention, the rotation permitting means is formed on the parking gear, and is formed on the convex portion that moves based on the displacement of the elastic member and the cover member, and the convex portion moves on both end faces thereof. And a recess that regulates the pressure.

  Therefore, according to the parking structure of the transmission according to the first aspect of the present invention, the rotation allowing means rotates the parking gear by a predetermined amount with respect to the bearing fixing member when the synchronizing device and the parking gear are engaged. Therefore, the synchro device and the parking gear can be engaged with each other regardless of the position of the synchro device and the parking gear, and the stop state of the vehicle can be maintained.

  In addition, when the parking gear is arranged on the bearing fixing member and the shift device selects the parking position, the synchro device meshes with the parking gear and mechanically locks the output shaft. Is no longer necessary. Since this synchronizer is operated by a shift device that shifts the gear in the transmission, the transmission mechanism can be used as an operating mechanism for the parking gear. As a result, the parking structure can be simplified and the space of the transmission can be saved as compared with the prior art.

According to the second aspect of the present invention, when the synchro device and the parking gear are engaged, the parking gear is rotated by a predetermined amount with respect to the bearing fixing member based on the displacement of the elastic member. Even if the synchro device and the parking gear are opposed to a position where it is difficult to mesh, this positional relationship is instantly avoided, and the synchro device and the parking gear are reliably meshed.
According to the third aspect of the present invention, after the synchronizer and the parking gear are engaged, the movement of the parking gear is restricted by the contact between the convex portion and the concave portion. Therefore, the stop state of the vehicle is maintained not by the elastic member but by the contact between the convex portion and the concave portion. As a result, the force acting on the elastic member is small, and the parking structure can be simplified and the space can be further reduced as compared with the conventional case.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a transmission 1 to which the parking structure of this embodiment is applied. The transmission 1 includes a transmission unit 2, a rear unit 4, and a center brake unit 6, and power from an engine (not shown) is transmitted to the transmission unit 2 via a clutch.
The transmission unit 2 includes a clutch housing 8 and a transmission case 14, and the housing 8 is enlarged in diameter toward the engine side, and a drive pinion (input shaft) 10 extends therein. The pinion 10 is rotatably supported on the housing 8 by a bearing 12.

  The transmission case 14 is joined to a reduced diameter portion of the housing 8, and a main shaft (output shaft) 16 extends coaxially with the pinion 10 inside thereof. The shaft 16 is rotatably supported by the case 14 by a bearing 17. A 5th gear 18 and a 4th gear 20 are arranged opposite to each other at an appropriate position of the shaft 16, and a single cone type synchronizer 22 is disposed between the gears 18 and 20. Further, a 3rd gear 24 and a 2nd gear 26 are arranged in the vicinity of the gear 18, and a 1st gear 30 and a Rev gear 32 are arranged in the shaft 16 in the vicinity of the gear 26. Synchronizers 28 and 34 are also arranged between the gears 30 and 32, respectively.

  On the other hand, a counter shaft 36 is juxtaposed with the shaft 16 in the case 14. Both ends of the shaft 36 are rotatably supported by the transmission case 14 by bearings 37 and 38, and the shaft 36 meshes with the gear 18 and the like to obtain a desired speed change. A sub-gear 40 and a reverse idler gear 42 that constitute a non-backlash mechanism to reduce idle noise are disposed at appropriate positions of the shaft 36.

  The case 14 is provided with a gear shift unit (shift device) 44 for selecting a target gear. Specifically, the gear shift unit 44 of the present embodiment moves along with the movement of the rail 46 in the axial direction in addition to the five shift rails 46 disposed above the shaft 16 as shown in FIG. Plates 50 and 52 are provided on a shift fork 48 and a rectangular reversing lever (not shown), and a target speed change is executed according to the gear selection by the unit 44.

Next, the rear portion 4 is provided with an extension housing (housing) 56, and the housing 56 is expanded in diameter toward the case 14 side and joined to the end portion of the case 14. The housing 56 may be formed integrally with the case 14.
Further, the main shaft 16 extends inside the housing 56, and the shaft 16 is rotatably supported by the housing 56 by a bearing 60. An end surface of the bearing 60 is in contact with an annular bearing retainer (bearing fixing member) 62, and the bearing 60 is fixed to the housing 56.

The retainer 62 is provided with the parking gear 74 of this embodiment. The parking gear 74 is sandwiched between the retainer 62 and a plate (cover member) 88, and a synchronizer (synchronizer) 98 and a parking gear. The parking gear 74 is configured to be rotatable with respect to the retainer 62 by a predetermined amount when meshing with the 74.
More specifically, as shown in FIGS. 2 and 3, first, the retainer 62 has four corners fixed to the housing 56 by four bolts 72, and the retainer 62 has a central portion facing the case 14. An annular bulging portion 64 that bulges out is provided. A cutout portion (rotation permitting means) 66 is formed on the outer peripheral portion of the bulge portion 64 toward the axial center of the bulge portion 64. The cutout portion 66 has upper and lower end surfaces, and the shaft It has a predetermined depth in the circumferential direction toward the heart. Note that holes 70 for receiving six bolts 96 are formed in the end face 68 of the bulging portion 64.

  The bulging portion 64 is fitted into an annular parking gear 74, and 16 teeth 76 are formed at appropriate positions on the outer peripheral edge of the parking gear 74. On the other hand, a fitting recess 78 is formed in the inner peripheral portion of the parking gear 74 in a direction away from the axis, and the fitting recess 78 has a piece (rotation) as a protrusion protruding toward the axis. The movement permitting means) 80 is fitted. The fitting recess 78 is formed at a position corresponding to the notch 66, and the piece 80 is disposed at a substantially central position of the notch 66. Then, elastic members (rotation permitting means) 86, 86 are provided between the upper end surface of the protruding piece 80 and the upper end surface of the notch 66 and between the lower end surface of the piece 80 and the lower end surface of the notch 66. As a result, the elastic members 86 are supported by the retainer 62 and the parking gear 74.

  Next, a convex portion (rotation permitting means) 84 protruding toward the case 14 is provided on the end face 82 of the parking gear 74, and the convex portion 84 has a predetermined height in the circumferential direction toward the case 14. It is formed with a thickness and rotates around the hour hand or the counter hour hand based on the displacement of the elastic member 86. On the other hand, the end surface 82 of the parking gear 74 and the end surface 68 of the bulging portion 64 are in contact with an annular plate 88 to allow the convex portion 84 to rotate. That is, the retainer 62 and the plate 88 are fixed to each other by the bolt 94 inserted into the hole 94 and the hole 70 from the end surface 92 side of the plate 88. However, the parking gear 74 of this embodiment has the retainer 62 and the plate 88 fixed to each other. It is pinched so that it can rotate.

  Further, a concave portion (rotation permitting means) 90 is formed on a part of the outer periphery of the plate 88 toward the axis. The concave portion 90 is formed at a position corresponding to the convex portion 84, and the circumferential length of the concave portion 90 is larger than the circumferential length of the convex portion 84 by an angle corresponding to one pitch of the teeth 76. Yes. The right end surface of the convex portion 84 can be brought into contact with the right end surface of the concave portion 90, and the left end surface of the convex portion 84 can be brought into contact with the left end surface of the concave portion 90. By the contact, movement of the parking gear 74 is restricted. .

  Incidentally, a synchronizer 98 is disposed on the main shaft 16 in the vicinity of the plate 88. The synchronizer 98 includes a synchronizer hub 100 splined to the shaft 16, and the outer periphery of the hub 100 is configured to be able to mesh with a synchronizer sleeve 108. More specifically, as shown in FIG. 4, a plurality of shifting plungers 102 are provided on the outer periphery of the hub 100, and the plungers 102 are pressed against the inner groove of the sleeve 108 by the plunger springs 104. It is energized. Further, a thrust washer 103 and a snap ring 105 for restricting the movement of the plunger 102 in the thrust direction are provided on the side surfaces of the hub 100 and the plunger 102 on the parking gear 74 side.

  On the other hand, the outer peripheral side of the sleeve 108 is engaged with a stepped piece 112, and this piece 112 is connected to a ring (not shown) surrounding the synchronizer 98 and a rectangular reversing lever 110 further surrounding the ring. ing. The ring and the side portion of the reversing lever 110 are connected via a piece (not shown). A flat plate 111 is provided on the upper surface portion of the reversing lever 110, and the flat plate 111 moves as the rail 46 moves in the axial direction. In this embodiment, the reversing lever having the fork 48 and the flat plates 50, 52, and 111 is mixed, but it may be composed of only the fork or only the lever.

  Returning to FIG. 1 again, the center brake portion 6 is disposed at the tip of the main shaft 16. The center brake portion 6 has a cover 116 that opens toward the tip of the shaft 16, and a camshaft 124 and a shoe 126 are disposed therein. The shoe 126 is fitted on the flange 122 and is covered with a brake drum 118, and the drum 118 is fixed with a lock nut 120. Then, when the driver pulls the camshaft lever 128, the camshaft 124 rotates and pushes the shoe 126, and as a result, the shoe 126 presses against the drum 118 and fixes a propeller shaft (not shown).

Here, first, in the neutral position shown in FIG. 4, the plunger 102 is engaged with the inner groove of the sleeve 108.
Subsequently, when the flat plate 111 moves toward the direction away from the parking gear 74 by the selection of the parking position by the gear shift unit 44, the reversing lever 110 tilts around its upper surface portion, and as shown in FIG. The side surface portion rotates in a direction approaching the parking gear 74. At the same time, the piece 112 also moves toward the parking gear 74 and the sleeve 108 moves toward the parking gear 74. Specifically, the plunger 102 is disengaged from the inner groove of the sleeve 108, and the sleeve 108 presses the plunger 102 toward the hub 100 against the biasing force of the spring 104.

  Here, if the sleeve 108 and the tooth 76 of the parking gear 74 face each other at a position where it is difficult to mesh, in other words, the sleeve 108 faces the tooth 76 and is not disposed between the adjacent tooth 76 and the tooth 76. Even in this case, the piece 80 is pressed by the urging force of the elastic members 86, 86 arranged in the vertical direction in the notch 66, and the parking gear 74 moves around the hour hand or the counter hour hand against the retainer 62. Rotate in either direction. In addition, the amount of rotation is determined by the convex portion 84 coming into contact with the end surface of the concave portion 90, and the sleeve 108 is immediately disposed between the adjacent teeth 76. When the sleeve 108 and the teeth 76 are engaged with each other, the hub 100 and the parking gear 74 are fixed, and the main shaft 16 is fixed.

As described above, the present embodiment pays attention to the fact that the parking gear 74 is not completely fixed to the retainer 62 but the parking gear 74 is provided with degrees of freedom around both the hour hand and the counterclockwise hand in the rotational direction. It is a thing.
According to this embodiment, when the synchronizer 98 and the parking gear 74 are engaged, the parking gear 74 can be rotated by a predetermined amount with respect to the retainer 62. In any position, the synchronizer 98 and the parking gear 74 can be engaged with each other, and the stopped state of the vehicle can be maintained.

  Further, the parking gear 74 is disposed not on the counter shaft 36 but on the main shaft 16, and when the gear shift unit 44 selects the parking position, the synchronizer 98 meshes with the parking gear 74 and the shaft. Since 16 is mechanically locked, it is not necessary to extend the countershaft 36. Since the synchronizer 98 is operated by the gear shift unit 44 that changes the gear in the transmission 1, the transmission mechanism can be used as the operation mechanism of the parking gear 74. As a result, the parking structure can be simplified and the space of the transmission can be saved as compared with the prior art.

  Further, when the synchronizer 98 and the parking gear 74 are engaged, the parking gear 74 is rotated by a predetermined amount with respect to the retainer 62 based on the displacement of the elastic member 86, so that the synchronizer 98 and the parking gear 74 are temporarily assumed. The parking gear 74 moves to a position where it can be easily meshed even if it is opposed to a position where it is difficult to mesh, and the positional relationship where it is difficult to mesh is instantly avoided, and these meshing are reliably performed.

  Furthermore, after the synchronizer 98 and the parking gear 74 are engaged with each other, the movement of the parking gear 74 is restricted by the contact between the convex portion 84 and the concave portion 90. Therefore, the stop state of the vehicle is maintained not by the elastic member 86 but by the contact between the convex portion 84 and the concave portion 90. As a result, the force acting on the elastic member 86 is small, and the parking structure can be simplified and the space can be further reduced as compared with the conventional case.

Although the description of one embodiment of the present invention has been completed above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, the notch portion 66 is formed in the retainer 62 and the piece 80 is disposed in the parking gear 74. However, the present invention is not necessarily limited to this configuration, and the notch portion 66 is formed in the parking gear 74. The piece 80 may be formed and disposed on the retainer 62. Moreover, the recessed part 90 may be formed in the parking gear 74, and the convex part 84 may be formed in the cover member 88. In any of these cases, the effect that the vehicle stop state can be reliably maintained as described above. Play.

It is sectional drawing of the transmission with which the parking structure of a present Example is applied. It is a front view of the parking gear of FIG. It is a disassembled perspective view of the parking gear etc. of FIG. It is a principal part enlarged view of the parking structure of FIG. 1 (neutral position). It is a principal part enlarged view of the parking structure of FIG. 1 (parking position).

Explanation of symbols

1 Transmission 16 Main shaft (output shaft)
44 Gear shift unit (shift device)
56 Extension housing (housing)
60 Bearing
62 Bearing retainer (bearing fixing member)
64 bulge portion 66 notch (rotation permitting means)
74 Parking gear 80 Projection (rotation permitting means)
84 Convex (rotation permitting means)
86 Elastic member (rotation permitting means)
88 Plate (Cover member)
90 Recess (Rotation permitting means)
98 Synchronizer (Synchronizer)

Claims (3)

An output shaft to which the output of the transmission is transmitted and rotatably supported by a housing via a bearing;
A bearing fixing member for fixing the bearing to the housing;
A parking gear provided on the bearing fixing member;
A cover member that pivotably holds the parking gear and is coupled to the bearing fixing member;
A shift device for shifting gears in the transmission;
A synchronizer that is disposed in the vicinity of the parking gear on the output shaft and meshes with the parking gear to make the output shaft non-rotatable when a parking position is selected by the shift device;
A parking structure for a transmission, comprising: a rotation permitting means for allowing the parking gear to rotate a predetermined amount with respect to the bearing fixing member when the synchronizer and the parking gear are engaged with each other. . The rotation permission means is
A bulging portion formed in the bearing fixing member and fitted in the parking gear; and a notch portion formed toward an axis at an outer peripheral edge of the bulging portion;
A protrusion formed on the parking gear and protruding into the notch,
2. The transmission according to claim 1, further comprising: an elastic member that is disposed between the notch and the protrusion and rotates the parking gear by a predetermined amount with respect to the bearing fixing member. Parking structure. The rotation permission means is
A convex portion formed on the parking gear and moving based on displacement of the elastic member;
The parking structure for a transmission according to claim 2, further comprising a recess formed on the cover member and restricting movement of the protrusion at both end faces thereof.

Images