JP2015175397A - Dog clutch and speed change gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress backlash after shift change-over to make driving feeling excellent.SOLUTION: A dog clutch 1 is used in an engagement clutch of a non-synchromesh type speed change gear, and in the dog clutch 1, on an engagement surface with a female dog gear having a plurality of engagement holes in a circumferential direction, a plurality of salients 5A, 5B capable of being engaged with the engagement holes are protrusively provided on a concentric circle. The salients 5A, 5B are arranged at positions of being capable of being engaged with both ends in the circumferential direction of the engagement hole, and the salient 5A is formed higher than the salient 5B.

Description

  The present invention relates to a dog clutch used for a meshing clutch of a transmission of an automobile or a motorcycle, and a transmission using the dog clutch.

In a transmission of an automobile or a motorcycle, as disclosed in Patent Document 1, a plurality of driven gears meshing with a drive gear of an input shaft are provided on an output shaft parallel to the input shaft, and by sliding in the axial direction. A meshing clutch that engages and disengages with the driven gear is splined. Therefore, when the shift lever is operated, the meshing clutch is slid by the operating means such as the shift / select mechanism and the selector fork and engaged with the driven gear, and the rotational torque of the input shaft is transferred from the drive gear to the output shaft via the driven gear and the meshing clutch. Will be communicated.
As this meshing clutch, as disclosed in Patent Document 2, a dog latch having a plurality of convex portions concentrically protruding on the engagement surface with the driven gear is well known. By engaging the convex portion of the dog clutch with an engaged portion provided concentrically with the female dog gear, the dog clutch is integrated in the rotational direction.

JP 2006-347408 A JP 2007-139110 A

  By the way, in the synchromesh type transmission, a part called a synchronizer is interposed in the dog clutch, and the engagement is performed after the rotational speeds of the dog latch and the female dog gear are synchronized by friction. In FIG. 6, since the dog clutch is directly engaged with the female dog gear without a synchronizer, as shown in FIG. 6, the dog clutch side convex portion 40 and the female dog gear side engaged portion are arranged so that the engagement can be performed smoothly. A relatively large clearance S, S is required in the circumferential direction between the concave portion 41. With this clearance S, rattling is likely to occur between the dog clutch and the female dog gear during acceleration / deceleration after shift switching, and the drive feel may be reduced.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a dog clutch and a transmission that have a good drive feeling by suppressing rattling after shift switching.

In order to achieve the above object, the invention according to claim 1 is used in a meshing clutch of a non-synchronous type transmission, and is engaged with a meshing surface with a female dog gear having a plurality of engaged portions in the circumferential direction. A dog clutch having a plurality of convex portions that can be engaged with the joint portion projecting on a concentric circle, wherein the plurality of convex portions are arranged at positions that can be engaged with both ends in the circumferential direction of the engaged portion, and A part of the convex portions is formed higher than the other convex portions.
According to a second aspect of the present invention, in the configuration of the first aspect, the high convex portions and the other convex portions are alternately arranged so that the adjacent high convex portions and the other convex portions are engaged. It is characterized in that it can be engaged with both ends in the circumferential direction of the part.
In order to achieve the above object, the invention according to claim 3 is directed to a female dog gear having a plurality of engaged portions in the circumferential direction, in which rotational torque is transmitted to the output shaft from the rotary shaft of the previous stage, and the female dog gear. A non-synchronous transmission comprising a meshing clutch that can be engaged and disengaged, wherein the dog clutch according to claim 1 or 2 is used as the meshing clutch.

  According to the present invention, even with a non-synchronous type, it is possible to obtain meshing without a clearance in the rotational direction. Therefore, rattling after shift switching is suppressed and the drive feel is improved.

It is explanatory drawing of a dog clutch, (A) shows a front, (B) shows a cross section, respectively. It is explanatory drawing of a female dog gear, (A) shows a front, (B) shows a cross section, respectively. It is explanatory drawing which shows the engagement state of the convex part of a dog clutch and the engagement hole of a female dog gear. It is explanatory drawing of a transmission. (A)-(C) is explanatory drawing which shows the state which a dog clutch approaches and engages with a female dog gear. It is explanatory drawing which shows the engagement state of the convex part of the conventional dog clutch, and the recessed part of a female dog gear.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory view showing an example of a dog clutch used in a transmission. The dog clutch 1 has a disk shape in which an inner spline 3 is formed in a through hole 2 formed in the center, and a ring-shaped groove 4 on the outer periphery. Is formed.
In addition, eight convex portions 5A, 5B,... Are projected on the outer peripheral edge of one surface, which is the meshing surface of the dog clutch 1, at equal intervals on a concentric circle. As shown in FIG. 4, the four convex portions 5 </ b> A having a high height and the four convex portions 5 </ b> B having a low height are alternately arranged. The dog clutch 1 including the convex portions 5A and 5B is formed by forging, for example.

  As shown in FIG. 2, the female dog gear 10 corresponding to the dog clutch 1 has a through hole 11 at the center and a tooth portion 12 on the outer periphery, and an engaged portion between the through hole 11 and the tooth portion 12. Are formed in a concentric circle so as to penetrate therethrough. As shown in FIG. 3, two adjacent convex portions 5 </ b> A and 5 </ b> B of the dog clutch 1 can be engaged with both ends of the engagement hole 13, respectively.

  The dog clutch 1 and the female dog gear 10 configured as described above are used in a transmission 20 as shown in FIG. 4, for example. The transmission 20 includes an input shaft 21 through which rotational torque is transmitted from the engine, a counter shaft 22 parallel to the input shaft 21, and an output shaft 23 parallel to the counter shaft 22. The input shaft 21 includes a drive gear 24. Is provided and meshes with a driven gear 25 provided on the counter shaft 22. The counter shaft 22, which is the rotational axis in front of the output shaft 23, is provided with three first to third counter gears 26 to 28, and each of the three first to first counters rotatably provided to the output shaft 23. It meshes with 3 driven gears 29-31. Therefore, the rotation of the counter shaft 22 transmitted from the input shaft 21 is transmitted to the first to third driven gears 29 to 31 via the first to third counter gears 26 to 28, respectively.

  In the output shaft 23, a first meshing clutch 32 is provided between the first driven gear 29 and the second driven gear 30, and a second meshing clutch 33 is provided between the second driven gear 30 and the third driven gear 31. Each is splined. The first meshing clutch 32 forms meshing surfaces on both front and rear surfaces, a neutral position in which neither of the first and second driven gears 29 and 30 is engaged, a slide position in which the first driven gear 29 is engaged, It is possible to slide to a slide position that engages with the two driven gears 30. The second meshing clutch 33 forms a meshing surface on one side, and is slidable between a neutral position where it is not engaged with the third driven gear 31 and a slide position where it is engaged with the third driven gear 31. The first and second meshing clutches 32 and 33 are slid by operating means such as a selector fork (not shown). Here, the dog clutch 1 of FIG. 1 is used as the second meshing clutch 33 and the third driven gear 31 is illustrated in FIG. Two female dog gears 10 are used.

  Therefore, as shown in FIG. 5A, when the dog clutch 1 is slid by the operating means from the neutral position where the dog clutch 1 is not engaged with the female dog gear 10, as shown in FIG. The four convex portions 5 </ b> A having the highest height first engage with the engagement holes 13 of the female dog gear 10. At this time, since the engagement holes 13 have a sufficient clearance in the rotation direction with respect to the respective convex portions 5A, the respective convex portions 5A are smoothly engaged with the respective engagement holes 13.

  Then, the rotation of the female dog gear 10 causes each convex portion 5 </ b> A to move relative to the end of each engagement hole 13, thereby synchronizing the dog clutch 1 and the female dog gear 10. At the same time, as shown in FIG. 3C, each of the four convex portions 5B having a low height engages with the opposite end portion of the engagement hole 13, so that each engagement as shown in FIG. The convex portions 5A and the convex portions 5B are positioned at both ends of the hole 13, and the dog clutch 1 and the female dog gear 10 are integrated in the rotational direction. Therefore, the rotational torque of the counter shaft 22 is transmitted from the third counter gear 28 to the output shaft 23 via the female dog gear 10 and the dog clutch 1.

  At this time, since the adjacent high convex portion 5A and the low convex portion 5B of the dog clutch 1 are respectively engaged with both ends of the corresponding engagement hole 13 of the female dog gear 10, both the convex portions 5A and 5B and the engagement hole 13 are engaged. In this state, there is almost no clearance in the rotational direction. Therefore, rattling is unlikely to occur between the dog clutch 1 and the female dog gear 10 during acceleration / deceleration.

  As described above, according to the dog clutch 1 and the transmission 20 of the above-described form, the plurality of convex portions 5A and 5B are arranged at positions that can be engaged with both ends in the circumferential direction of the engaging hole 13, and the convex portion 5A is convex By forming higher than the part 5B, even if it is a non-synchronous type, the meshing without a clearance in a rotation direction is obtained. Therefore, rattling after shift switching is suppressed and the drive feel is improved.

The number of protrusions provided on the dog clutch is not limited to the above-mentioned form, and can be increased or decreased as appropriate. The protrusions with a high protrusion height are arranged alternately with the low protrusions, and two protrusions are provided depending on the number of protrusions. It is not limited to the above-mentioned form, such as arranging them in a pair, arranging them in a point-symmetric position, or arranging only one of them.
In the above embodiment, a dog clutch having a convex portion on one side has been described. However, the present invention is not limited to this, and even a dog clutch having a convex portion on both sides like the first meshing clutch 32 in FIG. The invention can be adopted.

Further, the female dog gear is not limited to the through hole to be engaged, but the design can be changed, for example, a recessed portion with a bottom. Therefore, if the convex part of a dog clutch can be engaged, it can also be set as a to-be-engaged part between several convex parts protrudingly provided by the female dog gear.
In addition, the number of counter gears and driven gears and the arrangement of the input shaft, counter shaft, and output shaft are not limited to the above-mentioned configuration, and the dog clutch of the present invention can be used for a non-synchronous meshing clutch. If so, the design can be changed as appropriate.

  1 .... dog clutch, 2 .... through hole, 3 .... inner spline, 4 .... concave groove, 5A, 5B ... convex, 10 ... female dog gear, 13 ... engagement hole, 20 ... transmission, 21 ..Input shaft, 22 ..Counter shaft, 23 ..Output shaft, 26 ..First counter gear, 27 ..Second counter gear, 28 ..Third counter gear, 29 ..First driven gear, 30 2nd driven gear, 31 ... 3rd driven gear, 32 ... First meshing clutch, 33 ... Second meshing clutch.

Claims (3)

Used for meshing clutches of non-synchronous type transmissions, a plurality of convex parts that can be engaged with the engaged parts project on concentric circles on the meshing surface with a female dog gear having a plurality of engaged parts in the circumferential direction. A dog clutch,
The plurality of convex portions are disposed at positions that can be engaged with both ends in the circumferential direction of the engaged portion, and a part of the plurality of convex portions is formed higher than the other convex portions. Characteristic dog clutch.   The high convex portions and the other convex portions are alternately arranged so that the adjacent high convex portions and the other convex portions can engage with both ends in the circumferential direction of the engaged portion. The dog clutch according to claim 1. A non-synchronous type speed change comprising a female dog gear having a plurality of engaged portions in the circumferential direction and a meshing clutch that can be engaged with and disengaged from the female dog gear. Machine,
A transmission comprising the dog clutch according to claim 1 or 2 as the meshing clutch.

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