JP6416568B2 - transmission - Google Patents

Description

  The present invention relates to a transmission for shifting gears of an automobile, a motorcycle, a construction vehicle, an industrial machine, an agricultural machine, and the like.

  In general, in a vehicle transmission using a single clutch, the driving force is interrupted at the time of a shift, and a shift shock or an acceleration delay cannot be avoided. In addition, in construction vehicles, industrial machines, agricultural machines, etc. that have large running resistance and low speed energy, when the driving force is interrupted at the time of shifting, it may stop immediately and shifting may be difficult.

  On the other hand, the transmission of the twin clutch is known as a driving force that is not interrupted and can suppress shift shock and acceleration delay.

  However, the twin clutch transmission has a problem that its structure is complicated and heavy.

  On the other hand, Non-Patent Document 1 discloses a seamless shift transmission that is attracting attention as being capable of suppressing an increase in weight.

  The operation of this type of seamless shift transmission will be described below. Here, in order to simplify the description, a shift between the first speed and the second speed will be described.

  This seamless shift transmission has three first burettes and three second burettes engaged with the input shaft between the first gear and the second gear, and is configured to move according to the shift operation. . Clutch teeth are formed on the first speed gear and the second speed gear, and complex faces that are different in front and rear in the rotational direction are formed at both ends of the first and second burettes.

  The first buret and the second burette are configured to move toward the first gear or the second gear via a spring with respect to the operation of the select fork.

  With such a configuration, for example, when shifting to the first speed gear, the three first burettes mesh with the clutch teeth of the first speed gear, and then the remaining three second burettes mesh with the clutch teeth.

  At the time of shifting to the second speed, the three second burettes mesh with the clutch teeth of the second speed gear, and then the remaining three first burettes mesh with the clutch teeth.

  With the first and second burettes having such complicated faces and the selection operation via the spring, the driving force is not interrupted, the shift shock and the delay in acceleration can be suppressed, and the weight can be reduced. .

  However, there is a problem that the structure including the first bullet and the second bullet is complicated and the number of parts increases.

  Therefore, the applicant of the present application has proposed a transmission having a simple structure in which the driving force is not interrupted, the shift shock and the delay in acceleration can be suppressed, and the weight can be reduced.

  This transmission uses the cam action, and when the lower gear and upper gear clutch rings are engaged at the same time, the relative rotation of the lower gear and upper gear rings by the cam slope and internal circulation torque. The axial force in the mesh release direction is generated while allowing

  Thus, by the axial force in the disengagement direction at the time of simultaneous engagement, the clutch ring at the lower shift stage or the upper shift stage can be moved to the engagement release position.

  In this case, the clutch ring that has moved to the mesh release position due to the rebound of kinetic energy may move to the mesh position again, and a countermeasure has been desired.

JP 2012-127471 A

June 2005 Racecar Engineering (www.racecar / engineering.com)

  The problem to be solved is that the driving force is not interrupted, the shift shock and the delay in acceleration can be suppressed and the weight can be reduced, but the clutch ring that has moved to the mesh release position returns to the mesh position again. It is a point that moved.

The present invention has a simple structure, the driving force is not interrupted, the shift shock and the delay in acceleration are suppressed, the weight is reduced, and the clutch ring that has moved to the mesh release position is meshed again with a simple structure. In order to make it possible to restrict the movement to the position, when the clutch ring of the lower gear and the upper gear are simultaneously meshed by the shift-up operation or the shift-down operation of the gearshift operation unit, the gears are meshed simultaneously by the internal circulation torque. A transmission for releasing the meshing by generating an axial force in the meshing release direction in the clutch ring at the lower gear stage or the upper gear stage while allowing the relative rotation of the clutch ring, wherein the speed change operation unit rotates the operation output. And a shift operation unit that is shift-guided in the axial direction or the rotation direction by rotation of the operation output rotation unit, and the shift operation unit includes the clutch operation unit. Ring is the speed lower or interlocking form so as to move to the engagement position and meshing release position for shifting gears provided in the transmission upper, the clutch ring is provided between the operation output rotation unit and the shift operation section When the gears are engaged at the same time, the clutch ring of the lower shift stage or the upper shift stage receives play of the axial force and allows play in an axial direction to enter the disengagement position, and one of the operation output rotation part and the shift operation part direction meshing of the shift operation unit is projected in accordance with the supported formed in the same other and possible locking engagement portion forward and backward relative to the other said retractable locking engagement portion with the rotation of the operation output rotating portion The lock engagement portion can be released in the rotation direction of the operation output rotation portion by guiding and retracting the lock engagement portion by rotating the operation output rotation portion . A lock engaging portion, and when the clutch ring is subjected to an axial force in the disengagement direction and is in the disengagement position by the axial movement permitted by the play, the lock engagement portion is locked. The part is locked while allowing escape in the rotational direction.

  Since the present invention has the above-described configuration, the driving force is not interrupted, the shift shock and the delay in acceleration can be suppressed, and the weight can be reduced with a simple structure.

  Further, the lock engagement portion and the lock engagement portion can prevent the clutch ring that has moved to the mesh release position from being inadvertently moved to the mesh position again.

It is a schematic sectional drawing which shows the principal part of a transmission. (Example 1) It is a disassembled perspective view which shows the relationship between a clutch cam ring and a clutch ring. (Example 1) It is a perspective view of the state which engaged the clutch ring with the clutch cam ring. (Example 1) It is sectional drawing of a clutch cam ring. (Example 1) It is a principal part expanded view which shows the cam groove of a clutch cam ring. (Example 1) (Example 1) which is principal part sectional drawing which shows engagement of a clutch tooth | gear. It is a principal part expanded view which shows the cam groove of a clutch cam ring concerning the modification of a cam groove. (Example 1) It is a principal part expanded view which shows the cam groove of a clutch cam ring concerning the modification of a cam groove. (Example 1) (A) is sectional drawing of a clutch cam ring, (B) is a principal part expanded view which shows the cam groove of a clutch cam ring. (Example 1) FIG. 4 is a main part development view showing engagement of the engagement clutch, where (A) is a drive engagement position and (B) is a coast engagement position. (Example 1) It is a front view of a shift fork. (Example 1) 11A is a cross-sectional view of the pin protruding state, and FIG. 11B is a cross-sectional view of the pin retracted state. (Example 1) It is a principal part expanded view which shows the position of each movable pin with respect to the shift groove | channel in 1st speed side meshing and 2nd speed side neutral. (Example 1) It is shift groove sectional drawing in the XIV-XIV arrow line of FIG. (Example 1) It is shift groove sectional drawing in the XV-XV line arrow of FIG. (Example 1) It is a principal part expanded view which shows the position of each movable pin with respect to the shift groove in 1st speed side and 2nd speed side simultaneous meshing. (Example 1) It is a principal part expanded view which shows the position of each movable pin with respect to the shift groove in the middle of 1st speed side neutral movement and 2nd speed side meshing. (Example 1) It is a principal part expanded view which shows the position of each movable pin with respect to the shift groove in the 1st speed side neutral and 2nd speed side meshing completion. (Example 1) FIG. 17 is a main part development view showing the positions of the movable pins with respect to the shift groove in the first-speed side and second-speed side simultaneous meshing according to the modification, corresponding to FIG. 16. (Example 1) It is sectional drawing of a transmission. (Example 2) It is sectional drawing of a speed change operation part. (Example 2) The relationship between a rocker arm and a cam set is shown, (A) is an explanatory view showing a rocker arm and a cam positioned on the back side of the figure with the rocker arm in between, and (B) is a rocker An explanatory view showing a cam located on the front side of the figure with the arm and the rocker arm in between, (C) is a shift groove on the first speed side in the first-speed side and second-speed side simultaneous meshing of the corresponding first embodiment It is a principal part expanded view which shows the position of each movable pin with respect to. (Example 2) It is a block diagram of a cam. (Example 2) It is XXIV-XXIV sectional view taken on the line of FIG. (Example 2) It is XXV-XXV arrow directional cross-sectional view of FIG. (Example 2) FIG. 24 is a cross-sectional view taken along line XXVI-XXVI in FIG. 23. (Example 2) It is each sectional drawing of the XXVII-XXVII line arrow of FIG. (Example 2) It is a front view of the cam provided with the riding surface on the guide slope. (Example 2) It is a perspective view of the cam provided with the riding surface on the guide slope. (Example 2) It is a front view of a rocker arm. (Example 2) FIG. 31 is a cross-sectional view taken along line XXXI-XXXI in FIG. 30. (Example 2) (A) is the left view which made the cross section a part of FIG. 28, (B) is the right view of FIG. (Example 2) (A) is an operation explanatory view showing the relationship between the cam rotation and the rocker arm swing, and (B) shows the relationship between the cam rotation and the movable pin as viewed in the direction of arrow XXXIIIB-XXXIIIB in (A). FIG. (Example 2) (A) is an operation explanatory view showing the relationship between the cam rotation and the rocker arm swing, and (B) shows the relationship between the cam rotation and the movable pin as viewed in the direction of arrow XXXIVB-XXXIVB in (A). FIG. (Example 2) (A) is an operation explanatory view showing the relationship between cam rotation and rocker arm swing, and (B) shows the relationship between cam rotation and movable pin as viewed in the direction of arrow XXXVB-XXXVB in (A). FIG. (Example 2) (A) is an operation explanatory view showing the relationship between the cam rotation and the rocker arm swing, and (B) shows the relationship between the cam rotation and the movable pin as viewed in the direction of arrow XXXVIB-XXXVIB in (A). FIG. (Example 2) It is explanatory drawing which shows the relative locus | trajectory of the movable pin with respect to the cam at the time of a shift up. (Example 2) It is sectional drawing explaining the transfer to a contact guide surface and a lock | rock waiting surface from a guide slope and a rocking | fluctuation permission surface. (Example 2) It is explanatory drawing which shows the relative locus | trajectory of the movable pin with respect to the cam at the time of downshift. (Example 2) It is explanatory drawing which shows the correlation operation | movement of the cam mechanism at the time of the shift up of neutral-> 1st-> 2nd. (Example 2) It is explanatory drawing which shows the operation | movement of the cam which plays a positioning function at the time of a shift up, adding one frame. (Example 2) It is explanatory drawing of the cam which was playing the positioning function at the time of shifting up to 2nd speed changing to the side which performs a shifting function when shifting up to 3rd speed. (Example 2) It is explanatory drawing which shows the correlation operation | movement of the cam mechanism at the time of downshift of 2nd speed-> 1st speed. (Example 2) It is explanatory drawing which shows the operation | movement of the cam which has a positioning function at the time of a shift down, increasing frame | top | piece. (Example 2)

  With a simple structure, the driving force is not interrupted, the shift shock and acceleration delay can be suppressed, the weight can be reduced, and the clutch ring that has moved to the mesh release position can be moved to the mesh position again. For the purpose of enabling regulation, the speed change operation unit includes an operation output rotation unit and a shift operation unit that is shift-guided in the axial direction or the rotation direction by the rotation of the operation output rotation unit, and the shift operation unit includes the clutch The gear lower stage is formed when the ring is moved to the meshing position and the meshing release position with respect to the transmission gear, and is provided between the operation output rotation unit and the shift operation unit and the clutch ring is simultaneously meshed. Alternatively, the clutch output of the upper gear stage is provided with a play that allows the axial movement to receive the axial force and enter the disengagement position. The locking engagement portion formed on the other side of the lock engagement portion supported on one of the portions and capable of advancing / retreating with respect to the other is locked in the meshing direction of the shift operation portion to rotate the operation output rotation portion. A lock engaging portion that allows the clutch ring to be released in a direction, and receives the axial force in the disengagement direction and when the clutch ring is in the disengagement position in the axial operation permitted by the play, This is realized by locking the joint portion to the lock locking portion while allowing escape in the rotation direction.

  The operation output rotation unit is a shift drum that includes a plurality of shift grooves corresponding to a plurality of stages and is driven to rotate in response to a shift instruction. The shift operation unit separately includes a movable pin that engages with each shift groove. A shift fork that engages with the clutch ring, wherein the play is constituted by a wide portion in the groove width direction formed in the shift groove, and the lock engaging portion has an elastic body with respect to the shift groove and the elastic pin. The lock locking part is formed in the wide part of the shift groove at the mesh release position and is stepped in the groove width direction to drop the movable pin in the groove length direction. The drop-in portion having an escape guide surface may be used.

  The operation output rotation unit is a plurality of cams corresponding to the plurality of stages, each having a cam surface on the outer periphery and driven to rotate integrally by a shift instruction, and the shift operation unit includes each engagement guide by each cam surface. A plurality of rocker arms that can swing and rotate, and each rocker arm individually engages with each shift fork that operates each clutch ring, and the plurality of cams are each rocker arm A cam set that shares a pair of corresponding rocker arms apart from each other at two speeds or more on both sides of the swing axis direction of the arm, and the play is included in the cam set related to the shift guide of the shift operation unit. It is a gap formed between the cam surface of one cam and the rocker arm, and the lock engaging portion and the lock engaging portion are in front of the other cam of the cam set. To the rocker arm may be provided to each another.

  The lock engaging portion is a movable pin that is supported so as to be able to advance and retreat so as to protrude by an urging force of an elastic body on both sides of the rocking axis direction of each rocker arm and receive the engagement guide, and the lock engaging portion Is a lock surface that locks the movable pin in the meshing direction, a lock standby surface that waits the movable pin to shift to the lock surface, and the movable pin is moved toward the inner diameter side of the cam. You may provide the rocking | fluctuation permission surface which accept | permits rocking | fluctuation rotation, and the guide inclined surface which enables the transition and said escape of the said movable pin.

  The lock surface is continuous with the cam surface on one side in the rotational direction of the cam and is narrower than the cam surface and disposed on one side in the cam thickness direction, and the lock standby surface is within the thickness of the cam. Are arranged in a stepped manner on the inner diameter side of the lock surface, the rocking permissible surface is continuous with the lock standby surface, and the guide slope is formed on one side outer peripheral edge of the cam in the thickness direction and the rocking permissible When the rocker arm swings and rotates in the meshing direction with the engagement guide by the cam surface of one of the movable pins of the rocker arm. On the other hand, a movable pin that reversibly moves from the cam surface to the inner diameter side of the cam is guided by the guide slope to the rocking allowable surface side to allow the rocking rotation, and either of the rocker arms With one movable pin When the rocker arm swings and rotates from the meshing position to the mesh release position in the gap formed between the cam surface, the movable pin that moves to the outer diameter side on the other side is disengaged radially outward of the cam. Thus, the movable pin that protrudes on the outer periphery of the lock surface and engages in the meshing direction and engages with the lock surface may be allowed to escape to the swing allowable surface side by the guide slope.

  The main part of the present invention regulates inadvertent re-engagement of the clutch ring that has been disengaged in the transmission operation part of the transmission that enables seamless gear shifting with simultaneous meshing of the upper gear and the lower gear. The structure is added.

  Therefore, a transmission that enables seamless gear shifting with simultaneous meshing of the upper gear and the lower gear will be described, and then the gear shift operation unit will be described.

[Transmission overview and meshing clutch]
FIG. 1 is a schematic cross-sectional view showing the main part of the transmission of Embodiment 1 of the present invention.

  The transmission 1 in FIG. 1 is a so-called FR type vertical transmission of, for example, a front engine and a rear drive. The transmission 1 includes a first speed gear 3, a second speed gear 5, a third to sixth speed gear (not shown), and a back gear 7 as a plurality of speed change gears supported so as to be relatively rotatable on a driving force transmission shaft. As a clutch ring, a clutch ring 9 for 1st speed back, a clutch ring 11 for 2nd speed 6th speed, a clutch ring for 3rd speed 5th speed (not shown), a clutch ring for 4th speed (Not shown), and a shift operation unit 13 and a guide unit G.

  The transmission 1 includes a main shaft 15, a counter shaft 17, and an idler shaft (not shown) as driving force transmission shafts. In the following description, the axial direction means the direction of the axis of the driving force transmission shaft, and the rotational direction means the rotational direction of the driving force transmission shaft.

  The main shaft 15 and the counter shaft 17 are rotatably supported by a mission case (not shown) by bearings. The idler shaft is fixed to the mission case side.

  In the main shaft 15, the first speed gear 3 and the second speed gear 5 are supported by a support ring 23 via needle bearings 19 and 21 so as to be relatively rotatable. The support ring 23 is splined to the main shaft 15. 3rd to 6th gears (not shown) have the same structure and are supported on the main shaft 15 side through a needle bearing so as to be relatively rotatable. The back gear 7 is formed integrally with the clutch ring 9 for the first speed back. The number and arrangement of the transmission gears can be changed according to the specifications.

  Gears 25 and 27 are integrally or integrally provided on the counter shaft 17, and the first speed gear 3 and the second speed gear 5 on the main shaft 15 are always meshed with each other. Similarly, a 3rd to 6th gear (not shown) on the main shaft 15 is always meshed with a gear (not shown) provided integrally or integrally with the counter shaft 17.

  The reverse idler on the idler shaft (not shown) meshes with the gear 29 on the counter shaft 17 so that the back gear 7 can selectively mesh with the reverse idler.

  In this embodiment, the main shaft 15 has a first-speed back clutch ring 9, a second-speed sixth-speed clutch ring 11, a third-speed fifth-speed clutch ring (not shown), and fourth-speed. Since a clutch ring (not shown) is provided, a plurality of clutch rings are provided on the driving force transmission shaft.

  Clutch rings 9, 11,... Engage with the main shaft 15 in the rotational direction and move in the axial direction by selective operation, and are selectively used for the first speed gear 3, the second speed gear 5,. Meshing is possible.

  The clutch ring 9 is provided in the first meshing clutch 31, and the clutch ring 11 is provided in the second meshing clutch 33.

  Accordingly, the first speed gear 3 is selectively coupled to the main shaft 15 by the first meshing clutch 31, and the second speed gear 5 is selectively coupled to the main shaft 15 by the second meshing clutch 33. It becomes the composition which is done.

  Similarly, a 6-speed gear (not shown) is selectively coupled to the main shaft 15 by a second meshing clutch 33, and other transmission gears (not shown) are also connected by a meshing clutch (not shown) having other clutch rings. It is configured to be selectively coupled to the main shaft 15. By this selective coupling, it is possible to output a shift from the main shaft 15 to the counter shaft 17.

  The first and second meshing clutches 31 and 33 basically have the same meshing structure although there is a difference between the one-side meshing structure and the both-side meshing structure. The same applies to other meshing clutches not shown.

  As described above, the first-speed back clutch ring 9 of the first meshing clutch 31 is provided with the back gear 7 on one side and has a one-side meshing structure with clutch teeth on one side. The structure in which the back gear 7 is omitted is a mesh clutch structure constituted by a clutch ring for the fourth speed.

  The clutch ring 11 for the 2nd and 6th speed of the second meshing clutch 33 has a double-sided meshing structure with clutch teeth on both sides, and is a meshing clutch constituted by a 3rd and 5th speed clutch ring. Has the same structure.

  Here, the meshing structure of the first and second meshing clutches 31 and 33 with respect to the first gear 3 and the second gear 5 will be described. The meshing structure of the other meshing clutches with respect to the transmission gear is the same structure, and detailed description thereof is omitted.

  The first and second meshing clutches 31 and 33 include clutch cam rings 35 and 37 and clutch rings 9 and 11. Clutch teeth 39 and 41 are formed on the clutch rings 9 and 11 on the opposing surfaces of the clutch rings 9 and 11 and the first speed gear 3 and the second speed gear 5, respectively. 43 and 45 are formed. The clutch ring 11 is formed with clutch teeth 46 that mesh with a 6-speed gear (not shown).

  The clutch rings 9 and 11 are provided with flange portions 9a and 11a on the outer periphery, and cam protrusions 47 and 49 having a roller structure are provided on the inner periphery. This is because the roller structure of the cam protrusions 47 and 49 reduces sliding resistance with respect to a cam groove described later. The flange portion 9 a is engaged with the groove of the shift fork 51 of the speed change operation portion 13, and the flange portion 11 a is engaged with the groove of the shift fork 53 of the speed change operation portion 13 via the spacer ring 55. . The speed change operation unit 13 selectively operates the clutch rings 9 and 11, and details thereof will be described later.

  The clutch cam rings 35 and 37 are spline-fitted to the main shaft 15 and can rotate integrally. Cam grooves 57 and 59 formed symmetrically in the axial direction are formed in the clutch cam rings 35 and 37 at regular intervals in the circumferential direction.

  The clutch rings 9 and 11 are loosely fitted on the outer periphery of the clutch cam rings 35 and 37 so as to be movable in the axial direction. The cam projections 47 and 49 of the clutch rings 9 and 11 are engaged with the cam grooves 57 and 59 of the clutch cam rings 35 and 37.

  Due to this engagement, the clutch rings 9 and 11 are engaged with the main shaft 15 in the rotational direction via the clutch cam rings 35 and 37 and moved in the axial direction by selective operation by the speed change operation unit 13. The first gear 3 and the second gear 5 which are transmission gears can be selectively engaged.

  The cam protrusions 47 and 49 and the cam grooves 57 and 59 constitute the guide part G in this embodiment.

  In other words, the guide portion G is provided between the engagement of the clutch ring and the main shaft 15 that is the driving force transmission shaft, and the shift-up operation of the shift operation portion 13 causes the lower and upper shift clutch rings to mesh simultaneously. When this occurs, an axial force in the disengagement direction is generated while allowing relative rotation with respect to the main shaft 15 in the clutch ring at the lower gear stage.

  In the present embodiment, the guide portion G is provided between the engagement of the clutch rings 9 and 11 and the main shaft 15, and the shift-up operation of the speed change operation portion 13 causes the lower gear shift stage and the upper gear clutch ring 9, When the gears 11 are simultaneously meshed with each other, an axial force in the meshing release direction is generated while allowing the clutch ring 9 in the lower gear stage to rotate relative to the main shaft 15.

  The guide portion G is not limited to the form of the cam projections 47 and 49 and the cam grooves 57 and 59 as long as the same function is generated, and the cam protrusion corresponding to the cam groove is connected to the clutch cam. A form in which the clutch rings 9 and 11 are formed with bifurcated portions that are formed on the rings 35 and 37 and engage with both sides of the cam protrusion in the rotational direction is also conceivable.

  Cam grooves 57 and 59 and cam protrusions can be formed on the clutch rings 9 and 11 side, and cam protrusions 47 and 49 and bifurcated portions can be formed on the clutch cam rings 35 and 37 side.

  When the clutch rings 9 and 11 are engaged at the same time, the guide portion G 1 is engaged at the same time by the internal circulation torque inevitably generated in the mechanism regardless of the output torque of the engine. An axial force is generated while allowing relative rotation between the engagement of the clutch ring 9, which is one of the rings 9 and 11, with the main shaft 15. This axial force allows the clutch ring 9 to be disengaged while allowing simultaneous engagement of the clutch rings 9 and 11.

  2 is an exploded perspective view showing the relationship between the clutch cam ring and the clutch ring, FIG. 3 is a perspective view of the clutch ring engaged with the clutch cam ring, and FIG. FIG. 5 is a cross-sectional view of the cam ring, and FIG. 5 is a development of a main part showing a cam groove of the clutch cam ring.

  2-5 shows the 2nd meshing clutch 33 of a both-sides meshing structure.

  As shown in FIGS. 1 to 5, the cam groove 59 of the second meshing clutch 33 is formed symmetrically in the axial direction and continuously formed so as to penetrate in the width direction of the clutch cam ring 37. . The cam groove 59 is formed in a concave shape having a rectangular cross section, and the drive cam surface 59a serving as the engagement surface in the drive direction indicated by the arrow A and the guide cam surface 59b serving as the engagement surface in the coast direction indicated by the arrow B are arranged at the second speed. For the 6th speed, it is provided symmetrically in the axial direction. The drive direction and coast direction are described as rotational directions with reference to the clutch, cam, and ring 37. The drive direction means the rotational direction in which the clutch cam ring 37 receives the drive torque from the main shaft 15, and the coast direction means the rotational force (coasting torque) from the counter shaft 17 side of the clutch ring 11. This means the relative rotation direction of the clutch cam ring 37 with respect to the clutch ring 11.

  The drive cam surface 59a and the guide / cam surface 59b are opposed to each other in the rotational direction to form a cam groove 59. The groove width of the cam groove 59 formed by the drive cam surface 59a and the guide cam surface 59b is set so as not to prevent the smooth movement of the cam projection 49 and to suppress rattling. In this embodiment, the groove width of the cam groove 59 is set to be slightly larger than the diameter of the cam protrusion 49.

  The drive cam surface 59a includes a drive guide inclined surface 59aa and a drive engagement surface 59ab.

  The drive guide inclined surface 59aa is formed so as to incline backward in the width direction of the clutch cam ring 37 with respect to rotation in the drive direction. The drive engagement surface 59ab is formed continuously with the drive guide inclined surface 59aa, and is formed in parallel with the rotation axis direction.

  The guide cam surface 59 b is formed between the engagement of the clutch ring 11 and the main shaft 15, that is, between the engagement of the clutch ring 11 and the clutch cam ring 37, with respect to the axial direction of the main shaft 15. It is formed as an inclined surface.

  An axially symmetric guide cam surface 59b is coupled at the center in the width direction of the clutch ring 11 to form a V-shaped portion 59c. In the V-shaped portion 59c, an arc having the same curvature or the like can be formed in accordance with the outer peripheral circular shape of the cam projection 49. When the cam projection 49 is positioned on the V-shaped portion 59 c, the clutch ring 11 is a mesh release position that does not mesh with the second gear 5. This position is a neutral position.

  When the cam projection 49 is located on one side of the clutch cam ring 37, that is, on the second speed gear 3 side, the clutch ring 11 meshes with the second speed gear 5, and the cam projection 49 from the drive engagement surface 59ab. The drive torque can be transmitted to

  In the drive guide slope 59aa, the cam projection 49 in the middle of the shift is engaged, and the cam projection 49 is biased and guided in the meshing direction by the inclination with respect to the axial direction.

  When the cam projection 49 is positioned on one side of the clutch cam ring 37, the cam projection 49 abuts against the guide cam surface 59b in the coast direction. When the coasting torque is generated by the engine brake, the cam protrusion 49 does not move in the axial direction while being in contact with the guide / cam surface 59b.

  At this time, the cam projection 49 naturally receives the axial force in the meshing release direction due to the inclination of the guide / cam surface 59b. The axial force is received by the speed change operation unit 13 as will be described later, thereby preventing the cam protrusion 49 from moving.

  That is, although the guide cam surface 59b is a slope, the shift operation unit 13 prevents the clutch ring 9 or the clutch ring 11 from moving in the axial direction during engine braking.

  When the first-speed clutch ring 9 and the second-speed clutch ring 11 are simultaneously meshed and the cam projection 49 comes into contact with the guide cam surface 59b due to internal circulation torque (torsional torque), The cam protrusion 49 is guided by the guide / cam surface 59b by the axial force and is movable in the meshing release direction.

  This movement is permitted by the shifting operation unit 13 releasing the movement prevention of the clutch ring 9 as described later.

  FIG. 6 is a cross-sectional view of the main part showing the engagement of the clutch teeth.

  Regarding the engagement of the clutch teeth 41 and 45, the reverse gradient angle α is formed on the front and rear surfaces of the clutch teeth 41 and 45 in the rotational direction as the suction angle in the engagement direction.

  As shown in FIGS. 1 and 5, the inclination angle of the guide / cam surface 59b with respect to the axial direction is Θ, the radius (average radius) at the center of the rotation direction of the guide / cam surface 59b is R1, and the clutch teeth 39 and 43 are rotated. When the radius (average radius) at the center in the radial direction is R2, the axial force in the mesh release direction is proportional to (tan θ−tan αR1 / R2). Therefore, the axial force acting on the clutch ring 9 at the time of simultaneous meshing can be appropriately set in consideration of (tan θ-tan αR1 / R2).

  By setting the appropriate axial force, it is possible to prevent the clutch ring 9 from moving in the axial direction during engine braking without applying excessive force to the speed change operation unit 13 side. Further, when the movement prevention on the shift operation unit 13 side is released by play described later, the cam projecting portion 47 or the cam projecting portion 49 is moved in the axial direction by the guide / cam surface 59b by the action of the internal circulation torque at the time of simultaneous meshing. Relative movement allows the clutch ring 9 to move quickly in the disengagement direction.

  In the experiment conducted by the applicant of the present application, θ = 15 °, α = 5 °, and (tan θ−tan αR1 / R2) = 0.18 are set so that the engine brake works and seamless shifting by simultaneous meshing is impossible. It was possible to do it quickly. At Θ = 10 °, the clutch ring 9 may not be disengaged.

  Therefore, by considering (tan θ−tan αR1 / R2) = 0.18, the shaft of the clutch ring 9 or the clutch ring 11 can be used during engine braking without applying excessive force to the speed change operation unit 13 as described above. Prevent direction movement. In simultaneous meshing at the time of shifting up, the clutch ring 9 or the clutch ring 11 can be quickly moved in the meshing release direction.

  In addition, 0.18 is a value when a roller structure is used for the cam protrusions 47 and 49, and it is necessary to increase this value in a direct sliding structure using a protrusion that does not use the roller structure.

  FIG. 7 and FIG. 8 relate to a modification of the cam groove, and are main part development views showing the cam groove of the clutch cam ring.

In the cam groove 59A of FIG. 7, the drive cam surface 59Aa is formed as a surface inclined with respect to the axial direction of the main shaft 15 in the same manner as the guide cam surface 59Ab. Drive cam surface 59Aa and guide cam surface 59A
b is set in parallel, and the distance between the drive cam surface 59Aa and the guide / cam surface 59b is brought close to the diameter of the cam projection 49, and the backlash is made as small as possible.

  The function of the guide cam surface 59Ab is the same as in the example of FIG. The drive cam surface 59Aa engages the cam projection 49 in the middle of the shift, and biases the cam projection 49 in the meshing direction by the inclination with respect to the axial direction. This urging guide is performed even after the clutch teeth 41 of the clutch ring 11 are engaged with the clutch teeth 45 of the second speed gear 5.

  In the cam groove 59B of FIG. 8, the drive cam surface 59Ba is composed of a drive guide inclined surface 59Baa and a drive engagement surface 59Bab.

  The drive guide slope 59Baa has substantially the same structure as the drive cam surface 59a of FIG. 5, and the drive guide slope 59Baa and the guide / cam surface 59Bb are set in parallel. The distance between the drive guide slope 59Baa and the guide / cam surface 59Bb is set to be slightly larger than the diameter of the cam projection 49.

  The drive engagement surface 59Bab is formed as a surface inclined in the opposite direction at the end of the drive guide slope 59Baa. The drive engagement surface 59Bab is for axial positioning by engaging the cam projection 49, which has moved to the end of the drive guide slope 59Baa, with the drive engagement surface 59Bab.

  The drive engagement surface 59Bab can be formed with an arc having the same curvature in accordance with the circular outer periphery of the cam projection 49. In this case, the surface pressure when the cam protrusion 49 is engaged with the drive engagement surface can be reduced.

  The cam groove and cam protrusion engaging structure is the same for the first meshing clutch 31 having a one-side meshing structure. However, the clutch cam ring 35 of the first mesh clutch 31 is slightly different from the second mesh clutch 33 because the clutch teeth 39 are formed only on one side of the clutch ring 9. 5, 7, and 8, the cam groove 57 of the clutch cam ring 35 is formed only in the right half in the figure, and the left half is continuous with a groove parallel to the axial direction. It is formed. The left and right parallel grooves guide the clutch ring 9 toward the gear 29 on the counter shaft 17.

  The structure of the meshing clutch for four-speed meshing on one side can be formed in the same structure as the clutch cam ring 37 of FIGS. However, the cam groove 59 may not be symmetrical in the axial direction but may be formed in almost half of the axial direction.

  FIGS. 9 and 10 relate to a modification of the meshing clutch, FIG. 9A is a cross-sectional view of the clutch, cam, and ring, and FIG. 9B is a main portion development showing a cam groove of the clutch, cam, and ring. FIG. 10 and FIG. 10 show the meshing of the meshing clutch, (A) is a drive meshing position, and (B) is a main part development view showing the coasting meshing position.

  In this modification, a guide portion G that generates an axial force at the time of shifting is provided between the meshing of the clutch ring and the transmission gear. When the lower and upper clutch rings 9 and 11 are simultaneously meshed by the shift-up operation of the shift operation unit 13, the meshing is performed while allowing relative rotation with respect to the transmission gear meshing with the lower clutch gear ring. The axial force in the release direction is generated.

  As shown in FIGS. 9 and 10, in this modification, the guide portion G is provided between the meshes of the clutch rings 11 </ b> C... And the two gears 5 </ b> C. In this example, the groove 59C of the clutch cam ring 37C is formed straight in the axial direction.

  In the present embodiment, guide surfaces 41Ca and 45Ca having an inclination angle Θ with respect to the axial direction are formed with respect to the engagement of the clutch teeth 41C and 45C of the clutch ring 11C and the second gear 5C.

  9 and 10, the guide surfaces 41Ca and 45Ca have the same function as the function between the guide / cam surface 59b and the cam projection 49 in FIG. In other words, the internal circulation torque at the time of simultaneous meshing causes the clutch ring 9C to generate an axial force in the meshing release direction while allowing relative rotation of the clutch rings 9C and 11C with respect to the transmission gear, thereby allowing simultaneous meshing. The meshing can be released.

  By setting tan α based on the inclination angle α of the guide surfaces 41Ca and 45Ca to about 0.18, which is the same as described above, the same function as described above can be exhibited with respect to the engine brake. That is, when (tan θ−tan αR1 / R2) = 0.18, θ = 0 and α is set to a negative value as shown in FIG.

  The same applies to other meshing clutches.

  In addition, the transmission structure and the like described in Japanese Patent Application Laid-Open No. 2012-127471 previously proposed by the applicant of the present application can also be applied.

  This structure has a plurality of speed change gears supported by a driving force transmission shaft so as to be relatively rotatable, and a plurality of gears provided on the driving force transmission shaft are engaged in the rotational direction and moved in the axial direction by selective operation. A clutch ring capable of selectively engaging with the speed change gear, a speed change operating portion for selectively operating the clutch ring, and an engagement between the clutch ring and the driving force transmission shaft. Allowing the relative rotation with respect to the driving force transmission shaft to the lower gear or upper gear clutch ring when the lower gear and upper gear rings are engaged at the same time by shifting up or down operation of the operation unit And a guide portion that generates an axial force in the meshing release direction.

  The guide portions are cams that are formed between the clutch rings of the lower gear stage and the upper gear stage and the engagement of the driving force transmission shaft and are inclined in the opposite direction to the axial direction of the driving force transmission shaft. Each cam projection is fitted to each groove and each cam groove.

  The clutch ring engages with the transmission gear at a first meshing position in the axial direction and at a second meshing position where the meshing is shallower than the first meshing position. It is movable.

  A mechanism that places the clutch ring of the lower gear stage or the upper gear stage in the second meshing position when the driving force is transmitted by the clutch ring of the lower gear stage or the upper gear stage performing the selective meshing to transmit the driving force. It has.

  When the simultaneous meshing occurs, the cam groove and the cam projection engage with the simultaneous meshing by the internal circulation torque from the second meshing position, and the driving force is transmitted to the clutch ring of the shift lower gear or the gear shift upper gear. The axial force is generated between the engagements with the shaft to release the meshing while allowing the simultaneous meshing.

Therefore, the transmission 1 according to the present embodiment simultaneously meshes with the internal circulation torque when the clutch lower rings 9 and 11 are simultaneously meshed by the shift-up operation or the shift-down operation of the shift operation unit 13. The clutch ring 9 or 11 is allowed to rotate relative to the clutch ring 9 or 11 at the lower gear stage or the upper gear stage while generating an axial force in the mesh release direction to release the meshing. [Shift operation section]
11 is a front view of the shift fork, FIG. 12 is a sectional view taken along the line XII-XII in FIG. 11, (A) is a pin protruding state sectional view, and (B) is a pin retracted state sectional view, FIG. 13 is a development view of the main part showing the position of each movable pin with respect to the shift groove in the first-speed meshing and the second-speed side neutral, FIG. 14 is a cross-sectional view of the shift groove in the direction of arrows XIV-XIV in FIG. Is a cross-sectional view of the shift groove taken along line XV-XV in FIG. 13, FIG. 16 is an exploded view of the main part showing the position of each movable pin with respect to the shift groove in the first-speed side and second-speed side simultaneous meshing, and FIG. FIG. 18 is an exploded view of the main part showing the position of each movable pin with respect to the shift groove in the middle of the first speed side neutral movement and the second speed side meshing, and FIG. 18 shows the respective movements with respect to the shift groove at the completion of the first speed side neutral and the second speed side meshing. Main part showing pin position It is an open view.

  As described above, since the description will be made on the first speed side and the second speed side, the main part of the speed change operation unit 13 is illustrated in relation to the first and second meshing clutches 31 and 33 in FIG. Since the other gears have the same structure, redundant description is omitted.

  As shown in FIG. 1, the speed change operation unit 13 includes a shift drum 63 as an operation output rotation unit and shift forks 51 and 53 as a shift operation unit. The shift forks 51 and 53 are for the first speed back and for the second speed and the sixth speed, and other shift forks are provided in the same manner.

  The shift fork 51 is interlocked to move the clutch ring 9 to the meshing position and the meshing release position (neutral position) with respect to the first speed gear 3 by the engagement with the clutch ring 9. The shift fork 53 is also interlocked so as to move the clutch ring 11 to the meshing position and the meshing release position with respect to the second gear 5 by the above-described engagement with the clutch ring 11.

  As shown in FIGS. 1, 11, and 12, the shift forks 51 and 53 include a fitting boss 51a (53a) and a fork 51b (53b). The fitting boss portion 51a (53a) is supported by the shift rod 65 so as to be movable in the axial direction. The shift forks 51 and 53 are provided with pin support holes 51d and 53d, and movable pins 67 and 69 having a circular cross section are supported in the pin support holes 51d and 53d so as to be able to advance and retreat. The outer diameter of the movable pins 67 and 69 is almost the same as that of the pin support holes 51d and 53d so that there is no backlash. Coil springs 71 and 73 are interposed as elastic bodies between the end surfaces of the movable pins 67 and 69 and the back side surfaces of the pin support holes 51d and 53d. The coil springs 71 and 73 project the movable pins 67 and 69 with a biasing force with respect to a shift groove which will be described later.

  Accordingly, the movable pins 67 and 69 also serve as lock engaging portions that are supported by the shift forks 51 and 53 and can be advanced and retracted relative to the shift drum 63.

  The shift drum 63 includes a plurality of shift grooves 75 and 77 corresponding to a plurality of stages, and is configured to be rotationally driven according to a shift instruction. The rotation of the shift drum 63 is driven by an electric shift motor (not shown). The shift motor is driven to rotate in response to a shift instruction from a shift lever (not shown) or the like.

  The front end protrusions of the movable pins 67 and 69 of the shift forks 51 and 53 are engaged with the shift grooves 75 and 77 of the shift drum 63, respectively.

  The shift grooves 75 and 77 of each gear stage basically have the same structure. However, since each shift stage is distributed within 360 °, the phase and the direction in the axial direction are different.

  The first-speed (1st side) shift groove 75 will be described with reference to FIGS. The shift groove 75 on the first speed side is formed as a recess having a rectangular cross section. The shift groove 75 on the first speed side includes a neutral position groove portion 75a and a shift position wall surface 75b. The groove portion of the neutral position groove portion 75a includes the left and right wall surfaces in the groove width direction, and the wall surface of the shift position wall surface 75b refers to the shift function surface facing the groove width direction. The same applies hereinafter. The neutral position groove portion 75a is formed in the circumferential direction of the shift drum 63, and a shift position wall surface 75b is formed continuously with the neutral position groove portion 75a.

  On both sides of the shift position wall surface 75b, a shift up / down transition wall surface 75c continuous with the neutral position groove 75a and a shift / down transition wall surface 75d sandwiching the shift position wall surface 75b in the drum rotation direction are formed to be inclined in the axial direction. A parallelly inclined transition surface 75ca forming a shift groove 75 is formed with respect to the shift-up transition wall surface 75c, and a lock standby surface 75ba is linearly formed in the rotational direction on the transition surface 75ca. A wide portion 75e is formed in the axial direction of the lock standby surface 75ba. The lock standby surface 75ba is continuous with the neutral position groove portion 75a via the wide portion guide surface 75ea. The wide portion guide surface 75bb is provided with an inclination to facilitate the movement of the movable pin 67 in the present embodiment. The wide portion guide surface 75bb can also be formed parallel to the axial direction.

  The wide portion 75e constitutes a play F (see FIG. 16) formed in the shift groove 75 in the groove width direction. By this play F, when the clutch rings 9 and 11 are simultaneously meshed, it is possible to allow the guide portion G to receive the axial force of the clutch ring 9 at the lower gear stage and to move to the mesh release position.

  As shown in FIGS. 13, 14, and 16, this play F allows the axial movement of the movable pin 67 without constraining the movable pin 67 between them, and the shift drum 63 that is the operation output rotating portion and the shift operation. It is the structure provided between the shift forks 51 which is a part.

  The wide portion 75e is formed with a drop portion 79 as a lock engaging portion. The drop-in portion 79 is formed as a recess having a rectangular cross section deeper than the lock standby surface 75ba, and includes a lock surface 79c that is stepped in the groove width direction with respect to the lock standby surface 75ba.

  Therefore, the drop portion 79 is formed in the wide portion 75e of the shift groove 75 at the mesh release position and allows the movable pin 67 to drop. Due to this depression, the protruding movable pin 67 can be locked in the meshing direction of the clutch ring 9. That is, when the clutch ring 9 receives the axial force in the disengagement direction with respect to the first speed gear 3 and enters the disengagement position by the axial operation permitted by the play F, the movable pin 67 is locked to the drop portion 79. It can be locked to the surface 79c.

  As shown in FIGS. 13 and 15, the drop portion 79 has guide slopes 79 a and 79 b that allow it to escape in the groove length direction. In FIG. 13, the guide slopes 79a and 79b are hatched. The guide slopes 79a and 79b are inclined surfaces, and allow the movable pin 67 to escape from the drop-in portion 79 in the rotation direction of the shift drum 63.

  When shifting up, the movable pin 67 may transition from the guide slope 79a to the neutral position groove 75a in the upshift direction, and when shifting down, the guide pin 79b may pass through the shift / down transition section 75d to the shift position wall surface 75b. it can.

  The shift groove 77 on the second speed side (2nd side) includes a neutral position groove 77a, a shift position wall 77b, a lock standby surface 77ba, a shift / up transition surface 77c, a shift / down transition surface 77d, a wide portion 77e, and a wide portion guide surface. 77bb, the drop part 79, the guide slopes 79a and 79b, and the lock surface 79c are provided similarly.

  The shift grooves 75 and 77 allow the first-speed side and second-speed side clutch rings 9 and 11 to be disengaged and engaged. Therefore, the shift position wall surface 77b on the second speed side is arranged so as to correspond to the drop portion 79 on the first speed side in the rotation direction of the shift drum 63. The first-speed-side and second-speed-side shift-up transition surfaces 75c and 77c and the shift-down transition surfaces 75d and 77d are in the opposite directions in accordance with the shift direction of the clutch rings 9 and 11. .

  The structure of the shift grooves of the other shift stages and the arrangement relationship between the upper and lower stages are similarly performed.

  A shift motor (not shown) of the shift operation unit 13 is driven based on the operation signal of the shift lever or the accelerator opening and the vehicle speed signal by the operation of the accelerator pedal. The shift drum 13 is rotationally driven by the drive of the shift motor. As the shift drum 13 is driven to rotate, the shift grooves 75 and 77 guide the movable pins 67 and 69 of the shift forks 51 and 53, and are selectively driven in the axial direction between the neutral position and the meshing position.

  By the selective driving of the shift forks 51 and 53, the first and second meshing clutches 31 and 33 or the back gear 7 are selected and operated. By this selection operation, the first-speed gear 3 and the second-speed gear 5 function selectively so that a shift-up / shift-down change can be performed.

[Shift up]
Here, for simplification of explanation, only the shift-up from neutral to the first speed (shift lower stage) and the second speed (shift upper stage) will be described. The same applies to the shift-up of other stages. In this description, reference is mainly made to FIGS. 1, 5, 13, and 16 to 18.

  When the shift drum 63 of the speed change operation unit 13 is rotated by a shift instruction to the first speed, the movable pin 67 in the neutral position groove 75a in FIG. 13 reaches the shift position wall surface 75b through the shift up transition surface 75c. The shift fork 51 moves in accordance with the guide of the movable pin 67, and the clutch teeth 39 of the clutch ring 9 mesh with the clutch teeth 43 of the first speed gear 3.

  As a result of the shift operation to the first speed, the cam projection 47 of the clutch ring 9 is positioned on the drive engagement surface 59Bab side as in FIG. However, the first-speed clutch cam ring 35 is provided with a drive cam surface 59a, a guide cam surface 59b, a drive guide inclined surface 59aa, and a drive engagement surface 59ab on the right half in the drawing. Referring to FIG. 5, the cam protrusion 47 is positioned on the right side of the drive engagement surface 59ab in the drawing. Hereinafter, the cam protrusion 49 of FIG.

  At this position, drive torque is applied from the main shaft 15 to the clutch teeth 39 and 43 via the clutch cam ring 35 and the clutch ring 9, and the driving force from the first speed gear 3 to the counter shaft 17 side via the gear 25. Can be transmitted.

  When the engine brake is applied at this time, the clutch ring 9 is rotated in advance with respect to the clutch cam ring 35 by the coasting torque, and the cam projection 47 (corresponding to the cam projection 49 in FIG. 5) is guided. It contacts the cam surface 59b. An axial force acts on the cam projection 47 by the guide cam surface 59b.

  On the other hand, since the movable pin 67 of the shift fork 51 is positioned on the shift position wall surface 75b as shown in FIG. 13, the movement in the axial direction is restricted and transmitted from the cam projection 47 to the clutch ring 9 and the shift fork 51. Receive the axial force.

  Since the axial movement of the cam projection 47 with respect to the guide / cam surface 59b is prevented by receiving the axial force at the speed change operation portion 13, the engagement of the meshing clutch is maintained. For this reason, the engine brake can be used.

  When the shift-up operation to the second speed is performed by the rotation of the shift drum 63, the first-speed movable pin 67 reaches the lock standby surface 75ba as shown in FIG. The up transition surface 77c is reached.

  At this time, since the first-speed movable pin 67 does not move in the axial direction, the engagement of the clutch ring 9 with the first-speed gear 3 is maintained.

  The shift fork 53 in FIG. 1 moves in response to the second-speed movable pin 69 being guided by the shift-up transition surface 77 c, and the clutch teeth 41 of the clutch ring 11 are moved to the clutch teeth 45 of the second-speed gear 5. To bite.

  This meshing results in simultaneous meshing on the first speed side and the second speed side. At this time, the coasting torque acts on the first speed side and the drive torque acts on the second speed side due to the internal circulation torque between the first speed side and the second speed side due to the mechanical engagement by simultaneous meshing regardless of the engine output torque.

  Due to these torques, the first-speed cam protrusion 47 contacts the guide cam surface 59b of FIG. 5, and the second-speed cam protrusion 49 contacts the drive guide slope 59aa. Due to this contact, an axial force in the meshing release direction acts on the first-speed cam projection 47 and an axial force in the meshing direction acts on the second-speed cam projection 49. In addition, when the cam protrusions 47 and 49 move in the axial direction due to the inclination of the guide cam surface 59b and the drive guide inclined surface 59aa, the clutch rings 9 and 11 are relatively opposite to each other with respect to the main shaft 15. Rotates and allows simultaneous meshing. In addition, a synchronizing action is generated to alleviate the shift shock.

  Even when only the guide cam surface 59b is inclined, the clutch ring 9 rotates relative to the main shaft 15 to allow simultaneous engagement.

  When the first-speed cam protrusion 47 moves along the guide cam surface 59b, the movable pin 67 of the shift fork 51 is positioned in the play F of the wide portion 75e as shown in FIG. For this reason, the movable pin 67 is restrained by the guide groove 75 in the play F and is allowed to move in the axial direction. The movable pin 67 moves at a high speed in the play F along with the movement of the clutch ring 9 and moves toward the drop portion 79 side. As a result of this movement, the movable pin 67 is positioned at the drop-in portion 79 at the disengagement position of the clutch ring 9 as shown in FIG. 17, and the movable pin 67 protruding by the urging force of the coil spring 71 is at the drop-down portion 79. Engage with the locking surface 79c in the down and meshing direction.

  This engagement prevents rebound from kinetic energy, prevents the clutch ring 9 from moving again in the meshing direction, and causes the clutch ring 9 that has been disengaged to mesh with the first-speed gear 3 inadvertently. There is no.

  On the other hand, when the movable pin does not have a depression function, the movement of the clutch ring 9 in the axial direction is very fast, and the movable pin 67 may collide with the wall surface of the wide portion 75e and bounce off. As a result, the clutch ring 9 may be engaged with the first speed gear 3 again.

  The embodiment of the present invention can surely prevent such a problem.

  When the shift drum 63 further rotates, the first-speed movable pin 67 reaches the start end side of the guide slope 79a as shown in FIG. 18, and the second-speed movable pin 69 shifts at the meshing position of the clutch ring 11. Located on the position wall surface 77b, the shift-up to the second gear is completed. At the completion position, the movable pin 69 is prevented from moving in the axial direction, so that the engine brake can be operated in the same manner as described above.

  Even when shifting up from the second speed to the third side, the movable pin 69 on the second speed side drops from the lock standby surface 77ba to the drop portion 79 by the play F by the rotation of the shift drum 63, and similarly disengages. The clutch ring 11 thus made does not inadvertently engage with the second speed gear 5.

  At the time of shifting up from the second speed to the third side, the movable pin 67 can smoothly shift to the neutral position groove portion 75a through the inclination of the guide slope 79a on the first speed side of the lower stage by the rotation of the shift drum 63. At this time, the movable pin 67 retreats to the inside of the pin support hole 51a against the urging force of the il spring 71.

  Shifting up from the 3rd speed to the 4th side, the 4th speed to the 5th speed, and the 5th speed to the 6th speed is similarly performed.

  The cam grooves 59A and 59B in FIGS. 7 and 8 also have substantially the same functions as the cam grooves 59 in driving force transmission, engine braking, and simultaneous meshing.

[Shift down]
This will be explained by shifting down from 2nd gear to 1st gear. The same applies to downshifting at other stages.

  In response to the downshift instruction, the shift drum 63 rotates in the reverse direction from the state shown in FIG.

  At the time of this rotation, the movable pin 67 moves from the drop portion 79 to the shift / down transition surface 75d through the slope of the guide slope 79b on the first speed side. The shift fork 51 moves in accordance with the guide of the movable pin 67 on the shift / down transition surface 75d, and the clutch teeth 39 of the clutch ring 9 mesh with the clutch teeth 43 of the first speed gear 3. At the meshing completion position, the movable pin 67 is positioned on the shift position wall surface 75b.

  On the second speed side, the movable pin 69 reaches the neutral position groove 77a from the shift-up transition surface 77c, and the clutch ring 11 releases the meshing with the second speed gear 5 to the neutral position.

[Effect of Example 1]
The operation output rotation unit according to the first embodiment of the present invention is a shift drum 63 that includes a plurality of shift grooves 75, 77,... Corresponding to a plurality of stages and is driven to rotate in response to a shift instruction. Is provided with movable pins 67, 69,... That engage with the respective shift grooves 75, 77,..., And shift forks 51, 53, that engage with the clutch rings 9, 11,. ...

  The play F is constituted by wide portions 75e, 77e,... In the groove width direction formed in the shift grooves 75, 77,.

  The lock engaging portion supports the movable pins 67, 69,... So as to be able to advance and retract so as to protrude with respect to the shift grooves 75, 77,... By the biasing force of the coil springs 71, 73,. It is.

  The locking portions are formed in the wide portions 75e, 77e,... Of the shift grooves 75, 77,... At the mesh release position, and are stepped in the groove width direction to drop the movable pins 67, 69,. In addition, it is a drop portion 79 having a guide slope 79a that allows escape in the groove length direction.

  For this reason, the guide part G works by the internal circulation torque at the time of simultaneous meshing, and seamless shift-up can be performed smoothly. At this time, since the disengagement through simultaneous meshing between the first gear and the second gear, etc., the released clutch ring 9 does not re-engage with the first gear 3 due to rebounding by kinetic energy, and seamless shift・ It is possible to make sure the up is done.

  The play F is only formed by the wide portions 75e, 77e,... Of the shift grooves 75, 77,.

  The movement of the clutch and ring can be prevented only by forming the drop portion 79, and the structure is simple.

  Escape from the drop-in portion 79 can be performed simply by providing the guide slope 79a, and the structure is extremely simple in this respect.

  The drop part 79 and the guide slopes 79a, 79b can be processed together with the shift grooves 75, 77,... And the wide parts 75e, 77e,.

[Modification]
FIG. 19 relates to a modification of the embodiment of the present invention and is a main part development view showing the position of each movable pin with respect to the shift groove in the first-speed side and second-speed side simultaneous meshing corresponding to FIG.

  As shown in FIG. 19, in this flat example, the inclination of the wide portion guide surface 75bb of the shift groove 75 with respect to the axial direction is set larger than in the embodiment shown in FIG.

  By setting the inclination of the wide portion guide surface 75bb, when the disengagement of the clutch ring 9 is started by the internal circulation torque as described above, the shift drum 63 is driven and the wide portion guide surface 75bb is moved to the movable pin 67. Can act on.

  By the action of the wide portion guide surface 75bb, the movable pin 67 is surely moved to the drop portion 79, and the engagement of the clutch ring 9 is surely released and the shift to the engagement prevention again by the lock surface 79c is ensured. Can be done.

  The inclination is similarly set for the wide portion guide surface 77bb in the second speed and the wide portion guide surfaces in the other stages.

[Others]
The rotation of the shift drum 63 can also be performed manually.

  A protrusion can be formed on the shift drum 63, and a groove can be formed on the shift fork to engage with the protrusion. In this case, the protrusion is cut at a portion corresponding to the wide portion to form a drop portion. The slope of the ridge is continued between the drop portion and the ridge.

  A shift arm may be interposed between the shift drum and the shift fork, and a similar configuration may be applied between the shift arm and the shift drum.

  The movable pins 67 and 69 can be advanced and retracted by a solenoid.

  A transmission gear, a clutch ring, a meshing clutch, and a guide part G can also be provided on the counter shaft 17 as a driving force transmission shaft.

  The guide portion G can be provided both between the clutch ring and the clutch cam cam ring and between the clutch ring and the transmission gear. In this case, the characteristics can be improved by setting both guide portions G.

  The transmission 1 is the same as the gear shifting principle described above. However, when the direction of the inclined surface of the cam groove of the guide portion G is reversed with respect to the clutch teeth and the upper gear and the lower gear are simultaneously meshed, An axial force can be applied so that the lower gear side is guided in the direction in which the clutch ring is engaged more deeply, and the upper gear side is guided in the neutral direction.

  Alternatively, the axial force can be applied only to the upper stage of the shift.

  This is because when the construction machinery, agricultural machinery, large trucks, etc. are traveling at a low speed, such as traveling on a muddy ground or climbing a hill, when the speed energy is small and the traveling resistance is large, a greater driving force is required, so a downshift is required. In such a situation, when shifting down with a normal meshing transmission, if the driving force is interrupted even for a short time, the vehicle stops, causing problems such as difficulty in climbing.

  On the other hand, in the modified example in which the direction of the inclined surface of the cam groove is opposite to the clutch teeth, the driving force can be changed without interruption, so that it is possible to easily shift and down and maintain traveling. .

  A torque converter may be interposed between the engine and the main shaft 3. In this case, in a normal automatic transmission, there is a stall torque in the torque converter, so that it is impossible to cut by intermittent engagement with clutch teeth. However, the transmission 1 adopts a guide portion G that can cut even if torque exists. Thus, both smooth shifting and suppression of energy loss can be reliably achieved.

[Transmission overview and meshing clutch]
20 to 44 relate to Embodiment 2 of the present invention.

  20 is a cross-sectional view of the transmission, and FIG. 21 is a cross-sectional view of the speed change operation unit. Note that the basic configuration of the transmission of the present embodiment is the same as that of the first embodiment, and the outline will be described by adding D to the corresponding components.

  As shown in FIG. 20, the transmission 1 </ b> D is a first-speed gear 3 </ b> D, a second-speed gear 5 </ b> D, and third to sixth-speed gears 83, 85, 87, 89 as a plurality of speed change gears that are rotatably supported on the driving force transmission shaft. A back gear 7D is provided. The clutch ring includes a clutch ring 9D for 1st and 3rd speed, a clutch ring 11D for 2nd and 5th speed, a clutch ring 91 for 4th and 6th speed, etc., and a shift operation unit 13D and a guide unit GD are provided. I have.

  The transmission 1D includes an idler shaft (not shown) in addition to a main shaft 15D and a counter shaft 17D as driving force transmission shafts. In the following description, the axial direction means the direction of the axis of the driving force transmission shaft, and the rotational direction means the rotational direction of the driving force transmission shaft.

  The main shaft 15D and the counter shaft 17D are rotatably supported by the transmission case 105 by bearings 93, 95, 97, 99, 101, and 103. An idler shaft (not shown) is fixed to the mission case 105 side.

  2nd speed gear 5D, 4th to 6th speed gears 85, 87, 89 are supported on the main shaft 15D via needle bearings 21D, 107, 109, 111 so as to be relatively rotatable. The back gear 7D and the gears 113 and 115 are formed integrally with the main shaft 15D. The number and arrangement of the transmission gears can be changed according to the specifications.

  A first speed gear 3D and a third speed gear 83 are supported on the counter shaft 17D via needle bearings 119 and 121 so as to be relatively rotatable. The gears 123 and 125 and the gears 127 and 129 are spline-fitted to the counter shaft 17D. The gear 131 is provided integrally with the clutch ring 9D for the first and third speeds on the counter shaft 17D side. Further, the counter shaft 17D is integrally provided with a gear 134 that meshes with the ring gear 132 of the front differential device.

  The 2nd speed gear 5D on the main shaft 15D, 4th to 6th speed gears 85, 87, 89 are always meshed with the gears 123, 125, 127, 129 on the counter shaft 17D, respectively. The first speed gear 3D and third speed gear 83 on the counter shaft 17D are always meshed with the gears 113 and 115 on the main shaft 15D, respectively. The back gear 7D can be selectively engaged with the gear 131 on the counter shaft 17D side by a reverse idler.

  The counter shaft 17D is provided with a 1st and 3rd clutch ring 9D, and the main shaft 15D is provided with a 2nd and 5th speed clutch ring 11D and a 4th and 6th speed clutch ring 91. The drive force transmission shaft has a plurality of clutch rings.

  The clutch ring 11D engages with the main shaft 15 in the rotational direction and moves in the axial direction by a selective operation so that the second gear 5D and the fifth gear 87 can selectively engage with each other. The clutch ring 91 engages with the main shaft 15 in the rotational direction and moves in the axial direction by a selective operation so that the fourth gear 85 and the sixth gear 89 can selectively engage with each other.

  The clutch ring 9D is engaged with the counter shaft 17D in the rotational direction and is moved in the axial direction by a selective operation so that the first gear 3D and the third gear 83 can be selectively engaged.

  The clutch ring 9D is provided in the first meshing clutch 31D, the clutch ring 11D is provided in the second meshing clutch 33D, and the clutch ring 91 is provided in the third meshing clutch 133. ing.

  Accordingly, the first speed gear 3D and the third speed gear 83 are selectively coupled to the counter shaft 17D by the first meshing clutch 31D. The second gear 5D and the fifth gear 87 are selectively coupled to the main shaft 15D by the second meshing clutch 33D, and the fourth gear 85 and the sixth gear 89 are selectively coupled to the main shaft 15D by the third meshing clutch 133. It has a configuration.

  The first, second, and third meshing clutches 31D, 33D, and 133 basically have the same meshing structure.

  Here, the meshing structure of the first and second meshing clutches 31D and 33D with respect to the first speed gear 3D and the second speed gear 5D will be described. The meshing structure of the other meshing clutches with respect to the transmission gear is the same structure, and detailed description thereof is omitted.

  The first and second meshing clutches 31D and 33D include clutch cam rings 35D and 37D and clutch rings 9D and 11D. Clutch rings 9D and 11D and clutch teeth 39D and 41D of the clutch rings 9D and 11D and clutch teeth 43D of the first and third gears 3D and 5D are provided on the opposing surfaces of the first and third gears 3D and 5D, respectively. , 45D.

  The clutch ring 9D includes a circumferential groove portion 9Da on the outer periphery, and the clutch ring 11D includes a flange portion 11Da on the outer periphery. A cylindrical cam projection (not shown) projects from the inner periphery of each of the clutch rings 9D and 11D as in the first embodiment. A projecting portion of a shift fork (not shown) of the speed change operation portion 13D is engaged with the circumferential groove portion 9Da of the clutch ring 9D, and a flange portion 11Da of the clutch ring 11D is a groove of the shift fork 53D. Is engaged.

  The shift operation unit 13D selectively operates the clutch rings 9D, 11D, 91, and the reverse idler, details of which will be described later.

  The clutch cam rings 35D and 37D are spline-fitted to the counter shaft 17D and the main shaft 15D so as to be integrally rotatable. The clutch cam rings 35D and 37D have cam grooves formed symmetrically in the axial direction similar to those shown in FIGS. 5, 7, and 8 at regular intervals in the circumferential direction.

  The clutch rings 9D and 11D are loosely fitted on the outer periphery of the clutch cam rings 35D and 37D so as to be movable in the axial direction. The cam protrusions of the clutch rings 9D and 11D are engaged with the cam grooves of the clutch cam rings 35D and 37D in the same manner as in the first embodiment.

  By this engagement, the clutch rings 9D and 11D are engaged with the main shaft 15D in the rotational direction via the clutch cam rings 35D and 37D, and moved in the axial direction by selective operation by the speed change operation unit 13D. It is possible to selectively engage the first-speed gear 3D and the second-speed gear 5D that are transmission gears.

  The cam protrusion and the cam groove constitute a guide portion GD in the present embodiment.

  This guide portion GD is provided between the engagement of the clutch rings 9D and 11D and the main shaft 15D which is a driving force transmission shaft, and the shift ring up and down operation of the shift operation portion 13D causes the clutch ring at the lower shift stage and the upper shift stage. When the gears 9D and 11D are engaged at the same time, the clutch ring 9D at the lower gear stage is allowed to rotate relative to the counter shaft 17D while generating an axial force in the engagement release direction.

  The specific configuration of the guide part GD is the same as that of the first embodiment.

[Shift operation section]
As described above, the description will be centered between the first speed side and the second speed side, and other stages will be referred to as necessary. Other gears have substantially the same structure, and the description may be omitted.

  The shift operation unit 13D of the present embodiment has a configuration in which a pair of cams and the pair of cams share a rocker arm as a cam set instead of the shift drum and the shift fork of the first embodiment. The relationship between the cam set and the rocker arm will be described later with reference to FIG.

  As shown in FIG. 20, the shift operation unit 13D is provided in the transmission case 105 and drives the plurality of shift forks 53D, 135... And the plurality of shift forks 53D, 135. It is equipped with CA.

  The plurality of shift forks 53D,... Are fixed individually to a total of four shift rods 137, 139,. The shift rods 137, 139,... Are supported on the mission case 105 so as to freely move in the axial direction, and the cam device CA is attached to the mission case 105.

  The shift rods 137, 139,... Are individually provided with engaging portions 141,. As shown in FIG. 21, the cam device CA has a cam mechanism CA1 for the back gear, a cam mechanism CA2 for the first and third speeds, a cam mechanism CA3 for the fourth and sixth speeds, and a cam for the second and fifth speeds. A mechanism CA4 is provided.

  The cam mechanisms CA1 to CA4 are provided for each of shift rods 137,. The cam mechanisms CA1 to CA4 include cam sets 145, 147, 149, and 151 and a plurality of rocker arms 153, 155, 157, and 159 as shift operation units for the cam mechanisms CA1 to CA4. The rocker arms 153, 155, 157, and 159 are shift-guided in the rotation direction by the rotation of the operation output rotation unit, and can swing and rotate.

  The shift guides of the rocker arms 153, 155, 157, 159 are performed by the respective engagement guides by the cam surfaces of the cam sets 145, 147, 149, 151. The rocker arms 153, 155, 157, and 159 cause the concave engaging portions 141,... To move in the shift direction in the axial direction by the shift guide.

  Accordingly, the rocker arms 153, 155, 157, 159 are engaged with the concave engaging portions 141 as described above to operate the clutch rings 9D, 11D, 91, and the shift forks 53D, 135, .. is engaged.

  The cam sets 145, 147, 149, 151 are attached to the cam shaft 161 and are provided with cams 163, 165, 167, 169, 171, 173, 175, 177 as operation output rotating portions corresponding to a plurality of stages. Each of the cams 163, 165, 167, 169, 171, 173, 175, and 177 is formed of a plate cam, has a cam surface described later, and is rotationally driven together with the cam shaft 161 by a shift instruction. An electric shift motor is coupled to the cam shaft 161. An operation lever for manual operation can be attached instead of the shift motor.

  Next, the basic relationship between the rocker arm and the cam set, which is a feature of the embodiment of the present invention, will be described.

[Relationship between rocker arm and cam set]
FIG. 22 shows the relationship between the rocker arm and the cam set, and FIG. 22A is an explanatory view showing the rocker arm and the cam located on the back side of the figure with the rocker arm interposed therebetween, (B) ) Is an explanatory view showing the rocker arm and the cam located on the front side of the figure with the rocker arm in between, (C) is the first speed side in the corresponding first-speed side and second-speed side meshing of the first embodiment. It is a principal part expanded view which shows the position of each movable pin with respect to the side shift groove.

  22A and 22B show the rocker arm 155 and the cam set 147, the same applies to the other rocker arms 153, 157 and 159 and the cam sets 145, 149 and 151. However, there is a difference in phase depending on the gear position. FIG. 22C is a transcription from FIG. 16 for the purpose of understanding the correspondence with the second embodiment.

  In the cam set 147, a pair of cams 167 and 169 are arranged as two or more stages on both sides of the rocker arm 155 in the swing axis direction so as to be separated by 2 speeds or more. A pair of cams 167, 169 share a corresponding rocker arm 155, and each cam 167, 169 is involved in the swinging motion of one rocker arm 155. Each of the cams 167 and 169 is rotated integrally by the rotation of the cam shaft 161, and in this embodiment, is associated with a shift guide for the first and third gears.

  The play FD shown in FIG. 22B is formed between the cam surface of the cam 167 of the cam set 147 and the swinging direction of the movable pin 155a of the rocker arm 155. The cam 167 is related to a shift guide of the rocker arm 155 to the first speed.

  Similarly, the play FD may be formed between the swinging direction of the cam surface of the cam 169 and the movable pin 155b of the rocker arm 155. In this case, the cam 169 related to the shift guide to the third speed is one cam of the cam set 147. The same applies to the other stages.

  The gap FD corresponds to the play F of the first embodiment shown in FIG. In the first embodiment, together with the play F, a drop portion 79 as a lock engaging portion is formed in the same shift groove 75, and a movable pin 67 serving also as a lock engaging portion is engaged with the shift groove 75.

  On the other hand, in the present embodiment, the gap FD corresponding to the play F, the lock engagement portion, and the lock engagement portion are formed by being divided into a pair of cams 167 and 169.

  Therefore, when the cam 167 is related to the shift guide, the cam 167 functions as the shift-up transition surface 75c, the shift position wall surface 77b, and the shift-down transition surface 75d of the shift groove 75, and the cam 169 functions as the shift groove 75. The role of performing the functions on the transition surface 75ca and the lock standby surface 75ba side is formed.

  When the cam 169 is related to the shift guide, the roles of the cams 167 and 169 are reversed.

  That is, when the gap FD is formed between the cam 167 and the movable pin 155 a of the rocker arm 155, the cam 169 becomes the other cam of the cam set 147, and the lock engaging portion is defined by the cam surface side of the cam 169. Thus, the movable pin 155b of the rocker arm 155 serves as a lock engaging portion. When the gap FD is formed between the cam 169 and the movable pin 155b of the rocker arm 155, the cam 167 becomes the other cam of the cam set 147, and the lock engaging portion is constituted by the cam surface side of the cam 167. The movable pin 155a of the rocker arm 155 serves as a lock engaging portion.

  Next, the structure of a single cam and rocker arm in the relationship between the rocker arm and the cam set will be described.

[cam]
23 is a configuration diagram of the cam, and FIGS. 24 to 27 are cross-sectional views taken along line XXIV-XXIV, line XXV-XXV, line XXVI-XXVI, and line XXVII-XXVII in FIG. FIG. 28 is a front view of a cam provided with a riding surface on a guide slope, and FIG. 29 is a perspective view thereof.

  A pair of cams 163, 165, 167, 169, 171, 173, 175, 177 is arranged as a cam set 145, 147, 149, 151 for each rocker arm 153, 155, 157, 159. The pair of cams 163 and 165, the cams 167 and 169, the cams 171 and 173, the cams 175 and 177 are arranged at two or more speeds on both sides in the swing axis direction of the rocker arms 153, 155, 157, and 159, respectively. ing.

  The shapes of the cams 163 and 165, the cams 167 and 169, the cams 171 and 173, and the cams 175 and 177 are basically the same.

  The cam 167 of the first-speed and third-speed cam mechanism CA2 will be described as a representative. The other cams will be described with appropriate reference numerals.

  The cam 167 has a hexagonal hole 167a formed in the shaft center part, and the hexagonal hole 167a is fitted to the circumferential surface of the hexagonal cross section of the camshaft 161 so as to be integrally rotatable. Needless to say, the integral rotation structure of the cam 167 with respect to the cam shaft 161 may be a known structure such as a spline or a key.

  The circumferential surface of the cam 167 is a cam surface 167b. On the cam surface 167b, movable pins 155a and 155b of a rocker arm 153 described later move. A gap described later is formed as play between the cam surface 167b and the movable pin 155a at the meshing position of the clutch ring 9D with the first-speed gear 3D. By this gap, when the clutch and the ring are engaged at the same time, it is possible to allow the guide ring GD to receive the axial force from the lower clutch stage and move to the engagement release position. Details will be described later.

  As shown in FIGS. 23 to 27, the cam surface 167b includes a circular neutral portion 167ba and a protrusion 167bb. The neutral portion 167ba corresponds to the meshing release position of the clutch ring 9D. The protrusion 167bb corresponds to the meshing position of the clutch ring 9D. Therefore, when the movable pin 155a guided by the cam surface 167b is positioned at the circular portion 167ba, the clutch ring 9D is disengaged from the first-speed gear 3D, and when the movable pin 155a is positioned at the projection 167bb. This is the meshing position of the clutch ring 9D with respect to the first speed gear 3D.

  The cam 167 includes a lock surface 167c, a lock standby surface 167d, a swing allowable surface 167e, and a guide slope 167f as lock engaging portions.

  The lock surface 167c is formed on the outer periphery of the cam 167 and locks the movable pin in the meshing direction.

  The lock standby surface 167d waits for the movable pin to move to the lock surface 167c. Within the thickness of the cam 167, the surface is arranged in a stepped manner on the inner diameter side of the lock surface 167c and oriented in the radial direction. The lock standby surface 167d is continuous with the neutral portion 167ba via the transition surface 167da on one side in the rotational direction of the cam 167 (left side in FIG. 23). Transition surface 167da has the same function as transition surface 75bb of FIG. Between the lock surface 167c and the lock standby surface 167d, a contact guide surface 167g of the movable pin is formed as a side surface along the radial direction.

  The rocking allowance surface 167e allows the movable pin to move toward the inner diameter side of the cam 167 to allow the rocker arm 155 to rock and rotate. The peristaltic surface 167e is continuous with the lock standby surface 167d and is continuous with the neutral portion 167ba.

  The guide slope 167f allows the movable pin to move and escape. The guide inclined surface 167f is formed to be inclined in the radial direction between the outer peripheral edge on one side in the thickness direction of the cam 167 and the swing allowable surface 167e. The slope of the guide slope 167f is formed up to the height of the lock standby surface 167d in the thickness direction of the cam 167, and reaches the height of the contact guide surface 167g in the thickness direction of the cam 167. With this setting, the step between the rocking allowable surface 167e side of the guide slope 167f and the contact guide surface 167g is eliminated.

  Therefore, when the rocker arm 155 swings and rotates in the meshing direction by the engagement guide by one of the cam surfaces 167b and 169b of the movable pins 155a and 155b of the rocker arm 155, the inner diameters of the cams 169 and 167 are the other. The movable pins 155b and 155a that reversibly move from the lock surfaces 169c and 167c to the side are guided to the swing allowable surfaces 169e and 167e by the guide inclined surfaces 169f and 167f, thereby allowing the rocker arm 155 to swing and rotate.

  Further, the rocker arm 155 is disengaged from the meshing position by a gap formed between one of the movable pins 155a and 155b of the rocker arm 155 and the neutral portions 167ba and 169ba of the cam surfaces 167b and 169b. The movable pins 155b and 155a that move to the outer diameter side on the other side of the cam 167 and 169 protrude to the outer periphery of the lock surfaces 167c and 169c and engage in the meshing direction.

  The movable pins 155b and 155a engaged with the lock surfaces 167c and 169c are allowed to escape to the rocking permissible surfaces 167e and 169e by the guide inclined surfaces 167f and 169f when the cam shaft 161 rotates in the reverse direction.

  Thus, one of the pair of cams 167 and 169, the cams 171 and 173, and the cams 175 and 177 engages the clutch ring and the other opens, and alternately performs this function.

  FIG. 28 is a front view of a cam according to a modification, and FIG. 29 is a perspective view thereof.

  As shown in FIGS. 28 and 29, the cam 167 has a riding surface 167fa added to the upper edge of the guide slope 167f. The riding surface 167fa is formed flush with the contact guide surface 167g.

  Therefore, the movable pin 155a (155b) that has risen on the guide slope 167f can move from the swing allowing surface 167e to the lock standby surface 167d so as to shift from the riding surface 167fa to the contact guide surface 167g.

  The operation of the cam mechanism will be further described later.

[Rocker arm]
30 is a front view of the rocker arm, FIG. 31 is a cross-sectional view taken along the line XXXI-XXXI in FIG. 30, FIG. 32A is a left side view of a part of FIG. 30, and FIG. FIG. 31 is a right side view of FIG. 30. Although the movable pin is not a cross section, it is hatched.

  Each rocker arm 153, 155, 157, 159 is formed in the same structure. The rocker arm 155 will be described.

  Movable pins 155a and 155b are individually supported as lock engaging portions of this embodiment on both side surfaces of the rocker arm 155 in the swing axis direction. The movable pins 155a and 155b receive the engagement guide by the cam surface 167b and the like. The movable pins 155a and 155b are formed in a hollow cylindrical shape and are arranged separately on the left and right sides when the rocker arm 155 is viewed from the front. The movable pin 155b on the left side in FIG. 31 is located on the back side of the rocker arm 155 in FIG. 30, and is not shown. The movable pins 155a and 155b are supported to be movable forward and backward so as to protrude with respect to the rocker arm 155 by an urging force of an elastic body, for example, a coil spring 183.

  The rocker arm 155 has bifurcated intermediate portions 155c and 155d, and projecting edges 155ca and 155da are formed on the outer edges of the intermediate portions 155c and 155d. The movable pins 155a and 155b are attached to the shoulders of the intermediate portions 155c and 155d. A hole 155 e is formed in an arc shape at the center of the rocker arm 155 and is loosely fitted to the cam shaft 161. An action portion 155f is provided at the distal end portion of the rocker arm 155 and engages with the engaging portion of the shift rod. The rocker arm 155 is pivotably supported by a pivot 155g.

  The rocker arms 153, 155, 157, and 159 having such a configuration are continuously arranged in the housing 143 as shown in FIG. Each movable pin 153b, 155a, 155b, 157a, 157b, 159a abuts against the protruding edges 155da, 155ca, 157da, 155ca, 159da, 157ca of the adjacent rocker arms 153, 155, 157, 159 to prevent falling off. Has been. The movable pins 155a and 159b of the rocker arms 155 and 159 at the end abut against the housing 143 in the protruding state. The protruding edges 155da and 159ca of the rocker arms 155 and 159 also contact the housing 143.

  In each cam set 145, 147, 149, 151, the movable pins 153a, 153b, 155a, 155b, 157a, 157b, 159a, 159b of the rocker arms 153, 155, 157, 159 are cams 163, 165, 167, respectively. , 169, 171, 173, 175, 177.

[Relationship between cam rotation and rocker arm swing]
FIG. 33A is an operation explanatory view showing the relationship between the cam rotation and the rocker arm swing, and FIG. 33B is a sectional view of the main part in the arrow XXXIIIB-XXXIIIB showing the relationship between the cam rotation and the movable pin. FIGS. 34A and 34B are explanatory diagrams for explaining the relationship between the cam rotation and the rocker arm swing, and FIG. 34B shows the relationship between the cam rotation and the movable pin as viewed in the direction of the arrow XXXIVB-XXXIVB. FIG. 35 (A) is a partial sectional view, FIG. 35 (A) is an explanatory diagram showing the relationship between the cam rotation and the rocker arm swing, and FIG. 35 (B) is the XXXVB-XXXVB arrow view showing the relationship between the cam rotation and the movable pin. FIG. 36A is a function explanatory view showing the relationship between the cam rotation and the rocker arm swing, and FIG. 36B is a XXXVIB-XXXVIB showing the relationship between the cam rotation and the movable pin. In the direction of the arrow Main part is a cross-sectional view.

  The relationship among cam rotation, rocker arm swing, and movable pin engagement guide will be described with reference to FIGS. 33 to 36 regardless of the gear position on one side of the rocker arm. Here, the cam 167 will be described. The same applies to the other cams. However, the phase differs depending on the gear position. The relationship during the shifting operation between the rocker arm and the pair of cams on both sides will be described later.

  33, the movable pin 155a on one side protrudes from the rocker arm 155 by the biasing force of the coil spring 71 on the radially outer side of the cam 167, and is engaged and guided by the cam surface 167b. This position is a mesh release position of the clutch ring 9D, and the rocker arm 155 is in the neutral position. When the cam 167 rotates from this position, the position shown in FIG. 34 is obtained.

  In the position of FIG. 34, the movable pin 155a reaches the guide slope 167f, and the movable pin 155a retreats against the urging force of the coil spring 183. Accompanying this retraction movement, the movable pin 155a ascends the guide inclined surface 167f to the swinging permissible surface 167e side in accordance with the rotation of the cam 167.

  By the movement of the movable pin 155a with respect to the cam 167 toward the inner diameter side, the rocker arm 155 is allowed to rotate and is moved to the position shown in FIG. 35 through the state shown in FIGS.

  35, the movable pin 155a moves to the lock standby surface 167d side, the movable pin 155a waits on the lock standby surface 167d, and the protrusion of the movable pin 155a is restricted by the contact guide surface 167g.

  In the position of FIG. 36, the rocker arm 155 is rotated by play while the rotational position of the cam 167 remains unchanged. By this rotation, the movable pin 155a is disengaged radially outward of the cam 167, protrudes to the outer periphery of the lock surface 167c, and engages in the meshing direction. By this engagement, the rocker arm 155 is positioned at the neutral position.

[Relative trajectory of movable pin to cam]
FIG. 37 is an explanatory view showing the relative locus of the movable pin with respect to the cam at the time of shifting up, and FIG. 38 is a cross-sectional view for explaining the transition from the guide slope and the peristaltic surface to the contact guide surface and the lock standby surface. 39 is an explanatory view showing a relative locus of the movable pin with respect to the cam at the time of shifting down.

  Here, the relative relationship of the movable pin 155a when the cam 167 is rotated will be described.

  As shown in FIG. 37, the movable pin 155a is relatively moved from the neutral portion 167ba of the cam surface 167b to the guide inclined surface 167f → the swing allowable surface 167e → the lock standby surface 167d → the contact guide surface 167g → the lock surface 167c. Take a trajectory to make a transition.

  As shown in FIG. 38, there is a step between the guide slope 167f and the contact guide surface 167g. This step is eliminated when the guide slope 167f reaches the height of the contact guide surface 167g in the thickness direction of the cam 167.

  When the movable pin 155a moves up the guide slope 167f and reaches the peristaltic surface 167e, the C chamfered portion 155aa of the movable pin 155a corresponds to the edge of the contact guide surface 167g.

  For this reason, when the C chamfered portion 155aa gets over the edge portion of the contact guide surface 167g, the movable pin 155a can move from the rocking permissible surface 167e to the lock standby surface 167d.

  As shown in FIG. 39, when shifting down, the movable pin 155a takes a trajectory relatively moving from the lock surface 167c side of the cam 167 to the lock surface 167c → the guide inclined surface 167f → the swing allowable surface 167e → the neutral portion 167ba. .

  At the time of shifting down, the movable pin 155a can escape from the lock surface 167c to the swing allowable surface 167e side by the guide of the guide slope 167f.

[Cam device shift-up operation]
FIG. 40 is an explanatory view showing a correlation operation by a pair of cams of the cam mechanism at the time of shifting up from neutral → first speed → second speed, and FIG. 41 adds one frame of cam operation for performing a positioning function at the time of shifting up. It is explanatory drawing shown. Each sectional view in FIG. 41 shows the positional relationship of the movable pins at each rotational position of the cam shown in the rightmost column of FIG.

  FIG. 40 shows a first-speed and third-speed cam mechanism CA2 and a second-speed and fifth-speed cam mechanism CA4. Other shift speed cam mechanisms CA3 function in the same manner.

  In the neutral → first speed → second speed shift-up, for example, the cam 167 of the cam mechanism CA2 has a shift function, the cam 169 has a positioning function, the cam 175 of the cam mechanism CA4 has a shift function, and the cam 177 has a positioning function.

  In FIG. 40, the first-speed display column indicates the operation of the first-speed and third-speed cam mechanism CA2, and the second-speed display column indicates the operation of the second-speed and fifth-speed cam mechanism CA4. The ab display fields are all viewed from the cam 167 side, and the cam 169 and the movable pin 155b on the back side of the cam 167 are indicated by solid lines for convenience. The cd display fields are also viewed from the cam 175 side, and the cam 177 and the movable pin 159b on the back side of the cam 175 are indicated by solid lines for convenience.

  Reference numerals not shown in FIGS. 40 and 41 refer to FIGS. 23, 30, and 31 as appropriate. In this case, the reference numerals of the cam 167 and the rocker arm 155 described above as a representative are appropriately replaced with the reference numerals of the corresponding cam and rocker arm.

  For identifying each figure in FIG. 40, the first to fourth stages from the top to the bottom of the figure are used, and the first to fourth stages and symbols a to d are used. For example, the diagram on the top left is the first gear a1 and the diagram on the right is the first gear b1 and so on. This stage is not a shift stage, but means the upper and lower stages on the diagram display of FIG.

  The first to third and fifth stages in FIG. 41 represent the same parts as the 1st speed a1 stage surface to the 1st speed a4 stage surface of FIG. However, in FIG. 41, the fourth step of FIG. 40 is added, and the fifth step of FIG. 41 corresponds to the first speed a4 step surface of FIG.

  40, the first-speed and third-speed cam mechanism CA2 and the second-speed and fifth-speed cam mechanism CA4 are both in the neutral position. In the first-speed and third-speed cam mechanism CA2, the movable pins 155a and 155b are positioned at the neutral portions 167ba and 169ba of the cams 167 and 169 at the illustrated rotational positions, and in the second-speed and fifth-speed cam mechanism CA4, the illustrated rotational positions. The movable pins 159a and 159b are positioned at the neutral portions 175ba and 177ba of the cams 175 and 177.

  When the shift motor is driven by an instruction to shift to the first speed, the cam shaft 161 rotates in the direction of arrow A in FIGS. 40 and 41, and the cams 167, 169, 175, and 177 are shown in the second stage of FIG. Rotate to position.

  In this rotational position, the protrusion 167bb of the cam 167 drives the movable pin 155a, and the rocker arm 155 swings and rotates in one direction. At this time, in the cam 169 that is paired with the cam 167 as in the first speed a2 stage, the movable pin 155b moves to the swing allowable surface 169e side while being guided by the guide inclined surface 169f, so the rocker arm 155 swings and rotates. Is acceptable.

  By the rocking rotation of the rocker arm 155, the first-speed shift rod is axially driven through the engaging portion. By this axial driving, the clutch ring 9D is engaged with the first speed gear 3D and a shift to the first speed (shift to the first) is performed. At this time, the second-speed rocker arm 159 maintains neutral as in the second speed c2 stage and the second speed d2 stage. The same applies to the other-stage rocker arms... 155,.

  When the shift motor is driven by a shift up instruction from the first speed to the second speed, the cam shaft 161 further rotates, and the cams 167, 169, 175, 177 rotate to the positions shown in the third stage of FIG. .

  At this rotational position, the first-speed rocker arm 155 does not operate and the first-speed engagement is maintained and the projection 167bb of the cam 167 is disengaged from the movable pin 155a as in the first-speed b3 stage. Further, a play FD is formed between the movable pins 155a. At this time, in the cam 169 that is paired with the cam 167 as in the first gear stage a3, the movable pin 155b reaches the lock standby surface 169d and stands by.

  On the second speed side, the protrusion 175bb starts to be engaged with the movable pin 159a as in the second speed d3 stage, and the rocker arm 159 starts to swing and rotate. At this time, in the cam 177 that is paired with the cam 175 as in the second speed c3 stage, the movable pin 159b moves slightly toward the swing allowable surface 177e while being guided by the guide inclined surface 177f, so that the rocker arm 159 swings. Allow a little rotation.

  As the rocker arm 159 starts swinging and rotating, the clutch ring 11D starts to mesh with the second speed gear 5D via the engaging portion and the shift rod 139 (slightly meshed with the 2nd gear).

  When the second gear starts to mesh, the guide portion GD functions by being engaged with the first gear and the second gear simultaneously. Due to the function of this guide portion G, the axial force in the meshing release direction acts on the clutch ring 9D meshed with the first speed side of the lower gear stage as in the first embodiment, and the clutch ring 9D moves in the meshing release direction. Moving.

  The movement of the clutch ring 9D causes the rocker arm 155 to shift from the third level display in FIG. 41 to the fourth level display via the shift rod and the engaging portion. Due to this transition, the movable pin 155b is disengaged radially outward of the cam 169, protrudes to the outer periphery of the lock surface 169c, and engages in the meshing direction. By this engagement, the rocker arm 155 is positioned at the neutral position.

  By this positioning, the return from the first speed b4 stage of FIG. 40 where the rocker arm 155 is the mesh release position to the first speed b3 stage is restricted, and the clutch ring 9D once disengaged becomes the first speed gear. Engagement with 3D is prevented.

  On the second speed side, the cam shaft 161 further rotates as in the second speed d4 stage, the protrusion 175bb of the cam 175 drives the movable pin 159a, and the rocker arm 159 swings and rotates in one direction. At this time, in the second-speed c4th-stage cam 177 paired with the cam 175, the movable pin 159b is in the same situation as the first-speed a2th-stage, and the rocker arm 159 is allowed to swing and rotate.

  Similarly, the rocker arm 159 swings and rotates, so that the clutch ring 11D meshes with the second speed gear 5D and the shift to the second speed is completed (the shift is completed at the second stage). At this time, the first-speed rocker arm 155 maintains neutral as in the first-speed a4th stage and the first-speed b4th stage. The same applies to the other-stage rocker arms... 155,.

  Thus, the clutch ring 9D released by the first gear disengagement through the first gear second gear simultaneous meshing does not mesh with the first gear 3D again, and seamless shift-up is performed smoothly and reliably. Can be done.

  The same applies to the shift-up operation in 2nd speed → 3rd speed → 4th speed → 5th speed → 6th speed.

  FIG. 42 is an explanatory diagram showing that the cam having the positioning function when shifting up to the second speed changes to the side performing the shifting function when shifting up to the third speed.

  FIG. 42 is a continuation of the operation from the first speed a4 stage and the first speed b4 stage of FIG. When the shift motor is driven in response to a shift-up instruction from the second speed to the third speed, the shift from the first speed a4 stage and the first speed b4 stage in FIG. 40 is made as shown in FIG. 42, and the protrusion 169bb of the cam 169 Drives the movable pin 155b, and the rocker arm 155 swings and rotates in the opposite direction. At this time, in the cam 167 paired with the cam 169, the movable pin 155a is in the same state as the first speed a2 step surface, and the rocker arm 155 is allowed to swing.

  That is, the cam 169 that has performed the positioning function in the operation of FIG. 40 performs the shift function when shifting up to the third speed side.

[Cam device shift-down operation]
FIG. 43 is an explanatory view showing the correlation operation of the cam mechanism at the time of shifting down from the 2nd speed to the 1st speed, and FIG. 44 is an explanatory view showing the operation of the cam performing the positioning function at the time of shifting down with an increased frame. . 44 corresponds to FIG. 41, and each cross section in FIG. 44 shows the positional relationship of the movable pins at each rotational position of the cam shown in the rightmost column of FIG. 43 is specified in the same manner as in FIG.

  In addition, since the engagement of the transmission gear by the interlocking of the shift rod and the clutch ring is the same as described above, the operation of the rocker arm will be described here. 43 and 44 will be described by replacing the reference numerals of the cams 167 and the like described above with reference numerals of the corresponding cams and the like.

  The up-shifting to the second speed is completed by rotating the cam shaft 161 in the direction of arrow A as shown in the lowermost stage of FIG. 40 and the uppermost stage of FIG.

  In shifting down from the 2nd speed to the 1st speed, simultaneous engagement by the guide portion GD is not performed, and the 1st gear is engaged after the 2nd gear is removed.

  When the shift motor is driven by a downshift instruction from the second speed to the first speed, the cam shaft 161 rotates in the reverse direction in the direction of arrow B in FIGS. Rotate to the position shown in the first stage of FIG. 44 and the second stage of FIG.

  At this rotational position, the protrusion 175bb of the cam 175 is disengaged from the movable pin 159a as in the second speed d1 stage in FIG. 43, and the protrusion 167bb of the cam 167 drives the movable pin 155a as in the first speed b1 stage. start. At this time, since the movable pin 159b moves to the swing allowable surface 177e side while being guided by the guide inclined surface 177f of the cam 177 as in the second speed c1, the rocker arm 159 is allowed to swing. As in the first-speed a1 stage, the movable pin 155b is guided by the neutral portion 169ba of the cam 169, and the rocker arm 155 maintains neutral.

  With this operation, the rocker arm 159 returns to swing and the second speed is released.

  When the second speed is finished, the projection 167bb further drives the movable pin 155a and the first speed starts. At this time, as shown in the third stage in FIG. 44, the movable pins 155,... B move toward the rocking permissible surface 169e while being guided by the guide slope 169f of the cam 169. Allow swinging rotation in the direction.

  The rocker arm 155 swings and rotates, so that the first gear is engaged at the position of the first speed b2 stage in FIG. 43, and the movable pin 155b is connected to the cam 169 as in the first speed a2 stage and the fourth stage in FIG. The rocker arm 155 is allowed to swing in the meshing direction because the rocker arm 155 moves toward the swing allowing surface 169e while being guided by the guide slope 169f.

  This completes the downshift to the first speed (puts in the first gear). At this time, the second-speed rocker arm 159 maintains neutral as in the second speed c2 stage and the second speed d2 stage. The same applies to the rocker arms 153 and 157 in the other stages.

  When the camshaft 161 further rotates in the direction of arrow B according to the shift instruction, the protrusion 167bb is disengaged from the movable pin 155a, and the movable pin 155b is guided to the neutral portion 169ba of the cam 169 as shown in the fifth stage of FIG. Is removed and the transmission 1D becomes neutral.

  In this way, the downshift can be performed smoothly.

  The same applies to the shift-down operation in 6th speed → 5th speed → 4th speed → 3rd speed → 2nd speed.

[Effect of Example 2]
As described above, the operation output rotating unit according to the second embodiment of the present invention includes the cam surfaces 167b, 169b, .175b, and 177b on the outer periphery, and a plurality of cams 167 corresponding to a plurality of stages that are rotationally driven integrally by a shift instruction. 169, 175, 177, and the shift operation unit is a plurality of rocker arms 155, 159 that can be swung and rotated by respective engagement guides by the cam surfaces 167b, 169b, 175b, 177b. The arms 155, 159 are individually engaged with the shift forks 53D,... That operate the clutch rings 9D,..., And the cams 167, 169,. The rocker arms 155 and 159 are arranged at two or more speeds on both sides in the swing axis direction.

  The play FD is a gap formed between the rocking directions of the cam surfaces 167b, 169b, .175b, 177b and the rocker arms 155, 159 at the meshing position.

  The lock engaging portions are movable pins 155a, 155b, .159a that are supported so as to be able to advance and retract so as to protrude by the urging force of the coil spring 183 on both sides in the swing axis direction of the respective rocker arms 155, .159. 159b.

  The lock engaging portion is configured to move to the lock surfaces 167c, 169c, .175c, 177c and the lock surfaces 167c, 169c, .175c, 177c for locking the movable pins 155a, 155b, .159a, 159b in the meshing direction. Lock standby surfaces 167d, 169d, 175d, 177d for moving the movable pins 155a, 155b, .159a, 159b and the movable pins 155a, 155b, .159a, 159b are moved to the inner diameter side of the cam, and the rocker arms 155, .159 Oscillating permissible surfaces 167e, 169e, .175e, 177e and guide slopes 167f, 169f, .175f, 177f that allow the movable pins 155a, 155b, .159a, 159b to move and escape. I have.

  The locking surfaces 167c, 169c, .175c, 177c are continuous with the cam surfaces 167b, 169b, .175b, 177b on one side of the cams 167, 169, .., 175, 177 and the cam surfaces 167b, 169b, .175b. The cams 167, 169,..., 175, 177 are arranged on one side in the thickness direction, which is narrower than 177b.

  Lock standby surfaces 167d, 169d, .175d, and 177d are arranged in steps on the inner diameter side of the lock surfaces 167c, 169c, .175c, and 177c within the thickness of the cams 167, 169,. The allowable surfaces 167e, 169e, .175e, 177e are continuous with the lock standby surfaces 167d, 169d, 175d, 177d, and the guide inclined surfaces 167f, 169f, .175f, 177f are the cams 167, 169,. An inclination is formed between the outer peripheral edge on one side in the thickness direction and the rocking permissible surfaces 167e, 169e, .175e, 177e up to the height of the lock standby surfaces 167d, 169d, .175d, 177d.

  The rocker arms 155, 159 are engaged in the engaging direction by the cam guides 167b, 169b, 175b, 177b of one of the movable pins 155a, 155b, 159a, 159b of the rocker arms 155, 159. When swinging and rotating, the movable pins 155a, 155b, .159a, and 159b, which move back from the cam surfaces 167b, 169b, .175b, and 177b to the inner diameter side of the cams 167, 169,. The rocker arms 155, .159 are allowed to swing and rotate by being guided to the rocking permission surfaces 167e, 169e, .175e, 177e by the inclined surfaces 167f, 169f, .175f, 177f.

  A rocker arm 155, 159 is formed by a gap formed between one of the movable pins 155a, 155b, 159a, 159b of the rocker arm 155, 159 and the cam surface 167b, 169b, 175b, 177b. The movable pins 155a, 155b, .159a, and 159b that move to the outer diameter side on the other side when swinging and rotating from the mesh position to the mesh release position are disengaged radially outward of the cams 167, 169,. The locking surfaces 167c, 169c, .175c, 177c protrude to the outer periphery and engage in the meshing direction.

  The movable pins 155a, 155b, 159a, and 159b that engage with the lock surfaces 167c, 169c, .175c, and 177c are on the rocking permissible surfaces 167e, 169e, .175e, and 177e sides by the guide inclined surfaces 167f, 169f, .175f, and 177f. It is possible to escape.

  For this reason, as in the first embodiment, the guide portion GD works by the internal circulation torque at the time of simultaneous meshing, and seamless shift up can be performed smoothly. At this time, for example, the clutch ring 9D released by the disengagement through simultaneous meshing between the first gear and the second gear, for example, does not mesh with the first gear 3 again, and seamless shift-up is performed reliably. Can be made.

  The play FD is formed by guiding the movable pins 155a, 155b, .159a, and 159b to the inner diameter side of the guide slopes 167f, 169f, .175f, and 177f of the cams 167, 169,. The guide slopes 167f, 169f, .175f, 177f are simply formed on the cams 167, 169,.

  Escape from the lock surfaces 167c, 169c, .175c, and 177c can be performed simply by providing the guide slopes 167f, 169f, .175f, and 177f, and the structure is extremely simple in this respect.

  Lock surfaces 167c, 169c, .175c, 177c, lock standby surfaces 167d, 169d, .175d, 177d, guide slopes 167f, 169f, .175f, 177f, etc. are processed into cams 167, 169,. Can be processed easily.

1, 1D transmission 13, 13D transmission operation section 15, 15D main shaft (drive force transmission shaft)
17, 17D Counter shaft (driving force transmission shaft)
3, 3D 1st gear (transmission gear)
5, 5D 2-speed gear (transmission gear)
51, 53 ... Shift fork (shifting part)
53D Shift fork 63 Shift drum (operation output rotating part)
67, 69, 155a, 155b, 159a, 159b ... Movable pin (lock engagement part)
75, 77, ... Shift groove 75e, 77e, ... Wide part 79 Drop part (lock locking part)
79a Guide slope 155, 159 Rocker arm (shifting part)
167, 169, 175, 177 Cam (operation output rotating part)
167b, 169b, .175b, 177b Cam surface 167c, 169c, .175c, 177c Lock surface (lock locking part)
167d, 169d, 175d, 177d Lock standby surface 167e, 169e, 175e, 177e Oscillation permissible surface 167f, 169f, 175f, 177f Guide slope

Claims (5)

When the gearshift lower stage and the gearshift upper stage clutch and ring are simultaneously meshed by the shift-up operation or shift-down operation of the gearshift operation unit, the lower gear of the gearshift is allowed while allowing relative rotation of the clutch ring that is meshed simultaneously by the internal circulation torque. A transmission for releasing the meshing by generating an axial force in the meshing release direction in the clutch ring of the upper gear stage,
The shift operation unit includes an operation output rotation unit and a shift operation unit that is shift-guided in the axial direction or the rotation direction by the rotation of the operation output rotation unit,
The shift operation part is interlocked and formed to move the clutch ring to a meshing position and a meshing release position with respect to a transmission gear provided in the shift lower stage or the shift upper stage ,
An axial operation is provided between the operation output rotating portion and the shift operation portion, and when the clutch ring is engaged at the same time, the clutch ring at the lower shift stage or the upper shift stage receives the axial force and becomes the disengagement position. With acceptable play,
In response to the operation output rotary section and being supported one on the shift operation portion formed in the same other of retractable locking engagement portion relative to the other said retractable locking engagement portion with the rotation of the operation output rotating unit Protruding and locking in the meshing direction of the shift operation portion, and the lock engagement portion is guided by the rotation of the operation output rotation portion to escape the lock engagement portion in the rotation direction of the operation output rotation portion. With a lock locking part that enables by retracting ,
When the clutch ring receives an axial force in the disengagement direction and enters the disengagement position by the axial movement permitted by the play, the lock engagement portion is moved out of the lock engagement portion in the rotation direction. Lock while allowing,
Transmission characterized by that. The transmission according to claim 1,
The operation output rotating unit is a shift drum that includes a plurality of shift grooves corresponding to the lower shift stage and the upper shift stage and is driven to rotate in response to a shift instruction.
The shift operation unit is a shift fork that includes a movable pin that engages with each of the shift grooves and that engages with the clutch ring.
The play is constituted by a wide portion in the groove width direction formed in the shift groove,
The lock engagement portion is configured to support the movable pin so as to be able to advance and retract so as to protrude with an urging force of an elastic body with respect to the shift groove.
The lock engaging portion has a guide slope that is formed in a wide portion of the shift groove at the mesh release position and has a step in the groove width direction in which the movable pin is dropped and allows the escape in the groove length direction. It is a drop part,
Transmission characterized by that. The transmission according to claim 1,
The operation output rotation unit is a plurality of cams corresponding to the lower shift stage and the upper shift stage that have a cam surface on the outer periphery in the rotation direction and are rotationally driven integrally by a shift instruction,
The shift operation unit is a plurality of rocker arms that can swing and rotate with each engagement guide by each cam surface,
The plurality of rocker arms are individually engaged with a plurality of shift forks for operating the clutch ring,
The plurality of cams are arranged as cam sets sharing a pair of corresponding rocker arms apart from each other by two or more speeds on both sides of the rocker arm in the swing axis direction.
The play is a gap formed between the cam surface of one cam of the cam set related to the shift guide of the shift operation unit and the rocking direction of the rocker arm,
The lock engaging portion and the lock engaging portion are separately provided on the other cam and the rocker arm of the cam set,
Transmission characterized by that. 4. The transmission according to claim 3, wherein the lock engaging portion is supported so as to be able to advance and retreat so as to protrude by an urging force of an elastic body on both sides in the swing axis direction of each rocker arm. A movable pin,
The lock engaging portion moves the lock pin for locking the movable pin in the meshing direction, the lock standby surface for waiting the movable pin to shift to the lock surface, and the movable pin to the inner diameter side of the cam. A rocking permission surface that allows rocking and rotation of the rocker arm and a guide slope that allows the movable pin to move and escape.
Transmission characterized by that. The transmission according to claim 4, wherein
The locking surface is continuous with the cam surface on one side in the rotational direction of the cam and is narrower than the cam surface and arranged on one side in the cam thickness direction,
The lock standby surface is disposed in a stepped manner on the inner diameter side of the lock surface within the thickness of the cam,
The swing allowable surface is continuous with the lock standby surface,
The guide slope is inclined to the thickness of the lock standby surface between the outer peripheral edge on one side in the thickness direction of the cam and the rocking allowable surface,
When the rocker arm swings and rotates in the meshing direction by the engagement guide by the cam surface of one of the movable pins of the rocker arm, the other side can return from the cam surface to the inner diameter side of the cam. The moving movable pin is guided by the guide slope to the swing allowable surface side to allow the swing rotation,
When the rocker arm swings and rotates from the meshing position to the mesh release position through a gap formed between one of the movable pins of the rocker arm and the cam surface, the other rocker arm moves to the outer diameter side. The movable pin is disengaged radially outward of the cam and protrudes to the outer periphery of the lock surface to engage in the meshing direction,
The movable pin that engages with the lock surface can escape to the swinging allowable surface side by the guide slope.
Transmission characterized by that.

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