JP5185227B2 - Multi-speed transmission - Google Patents

Description

  The present invention relates to a multi-stage transmission in which a plurality of drive gears and driven gears are supported on a gear shaft parallel to each other in a state where they are always meshed with each other in each gear stage.

  In this always-meshing multi-stage transmission, one of the driving gear and the driven gear is fixed to the gear shaft, the other is rotatably supported on the gear shaft, and the rotating shaft of the gear that is rotatable by the engaging means. Shifting is performed by switching the gears to be engaged.

  A structure in which a lost motion mechanism is incorporated in a speed change driving means that is provided between a plurality of gears and a gear shaft and performs switching by switching engaging means that engage with each other has been filed earlier by the same applicant. (Patent Document 1).

Japanese Patent Application No. 2008-246754

  The shift drive means of the multi-stage transmission disclosed in Patent Document 1 includes four types of control rods arranged on the hollow center shaft of the gear shaft so as to be slidably contacted with the hollow inner peripheral surface of the gear shaft in the axial direction. The lost motion mechanism is in sliding contact with the inner side of the cam rod, and the lost motion mechanisms are arranged on the left and right sides of the four types of cam rods, and each lost motion mechanism is connected to a required cam rod.

The lost motion mechanism is interlocked by interposing springs acting in the axial direction between the control rod and the cam rods, and the lost motion mechanism is accommodated in the hollow of the gear shaft.
When shifting by moving the control rod, this lost motion mechanism allows the previous engagement when shifting from the state in which the engagement by the engagement means before the shift is maintained to the engagement state of the engagement means after the shift. The maintained engagement means can be released naturally and can be smoothly shifted, and the shift can be executed smoothly without interruption.

Shifting up during acceleration and downshifting during deceleration are performed smoothly as described above, but shifting down during acceleration and shifting up during deceleration are engaged previously maintained during shifting. Since the means is not released naturally, the gear cannot be shifted as it is.
However, since the control rod is moved by the lost motion mechanism even though the speed cannot be changed, the driver who performed the shift operation feels uncomfortable in the situation that the speed cannot be changed even if it can be operated.

  The present invention has been made in view of the above points, and the object of the present invention is to provide a lost motion mechanism that can perform a smooth speed change and can regulate a shift down operation during acceleration and a shift up operation during deceleration. The point is to provide a transmission.

  In order to achieve the above object, according to a first aspect of the present invention, a plurality of drive gears and driven gears are supported on gear shafts parallel to each other in a constantly meshing state for each shift stage, and the drive gears and the driven gears are supported. A plurality of gears are fixed to the gear shaft, and engaging means provided between the other plurality of gears and the gear shaft and engaged with each other are switched and driven by the speed change driving means to perform speed change. In the machine, the engaging means is for forward rotation that can be engaged only in each rotation direction of forward rotation in which the power from the internal combustion engine of the gear is transmitted and reverse rotation in which the power from the driving wheel side is transmitted. There are two types of engagement means for reverse rotation, and each of the engagement means includes an engagement convex portion provided with an engagement surface in the circumferential direction at a plurality of locations in the circumferential direction of the inner peripheral surface of each gear. The gear shaft can be freely moved in and out, and can be engaged with and disengaged from the engaging projection of each gear. An engaging member that engages, a plurality of cam rods that are slidably supported in the axial direction on the gear shaft, and that have a plurality of cam grooves formed on the sliding contact surface at a required position in the axial direction; A sliding contact surface of a cam rod that is inserted in a radial direction and moves in the axial direction; and a pin member that alternately moves forward and backward in contact with the cam groove to actuate the engagement member. A control rod provided on the hollow central shaft of the gear shaft inside the cam rod, and interposed between the outer peripheral surface of the control rod and the inner surfaces of the plurality of cam rods, and the control rod and each cam rod are axially arranged. A loss motion mechanism that is linked via an acting spring, and a regulating rod that moves integrally with the control rod is provided in the gear shaft in sliding contact with the cam rod, The restriction rod is formed with a notch capable of engaging the pin member together with the cam groove of the cam rod in sliding contact with each cam groove, and the restriction rod corresponding to the cam groove of the cam rod for forward rotation. The notch of the control rod is formed longer on the side opposite to the moving direction of the control rod at the time of upshifting than the cam groove when the gear is established, and the notch of the regulating rod corresponding to the cam groove of the cam rod for reverse rotation is formed. The notch is a multi-stage transmission that is formed longer than the cam groove in the state where the shift stage is established, on the side opposite to the moving direction of the control rod during the downshift.

  According to a second aspect of the present invention, in the multi-stage transmission according to the first aspect, the restriction rod is sandwiched between the forward rotation cam rod and the reverse rotation cam rod so as to slide relatively in the axial direction. It is provided so that it can move freely.

  According to a third aspect of the present invention, in the multi-stage transmission according to the first or second aspect, the restriction rod is formed as a separate member from the control rod, and moves integrally with the control rod by a coupling means. It is characterized by being combined.

  According to a fourth aspect of the present invention, in the multi-stage transmission according to the third aspect, the coupling means is a half cotter, and is provided on a fitting groove provided on an outer peripheral surface of the control rod and an inner surface of the regulating rod. The half cotter is fitted to both the fitting groove and the control rod is integrally coupled to the control rod.

  According to a fifth aspect of the present invention, in the multi-stage transmission according to any one of the first to fourth aspects, the cam rod and the regulating rod are configured such that a rod having the same function is opposed to the outer periphery of the control rod. It is characterized by being arranged at a symmetrical position.

  According to the multi-stage transmission of claim 1, the control rod is operated, and the multi-stage that performs a shift by switching one of the two types of engaging means for forward rotation and reverse rotation through the lost motion mechanism. In the transmission, a control rod that moves integrally with the control rod is provided on the gear shaft in sliding contact with the cam rod, and the notch of the control rod corresponding to the cam groove of the cam rod for forward rotation is Since it is formed longer than the groove in the direction opposite to the movement direction of the control rod when shifting up, if the control rod is moved to shift up during acceleration when power from the internal combustion engine is transmitted, Since the notch has a margin on the opposite side of the moving direction from the pin member of the engaging means in the engaged state, the control rod integrated with the regulating rod The upshift is smoothly executed by moving the control rod, but when the control rod is moved to shift down during acceleration, the notch of the regulating rod is moved in the moving direction more than the pin member of the engaging means in the engaged state. There is no room on the opposite side, and the movement of the control rod together with the restriction rod is restricted, the shift down operation itself is restricted, and the driver who tries to operate does not feel uncomfortable.

  Further, the notch of the regulating rod corresponding to the cam groove of the cam rod for reverse rotation is formed longer on the side opposite to the moving direction of the control rod at the time of downshifting than the cam groove in the established gear position. Therefore, when the control rod is moved to shift down during deceleration when power from the drive wheel side is transmitted, the notch of the regulating rod is on the opposite side of the moving direction from the pin member of the engaging means in the engaged state. Since there is room, the control rod integrated with the restriction rod moves and the downshift is performed smoothly, but if you try to move the control rod to shift up when decelerating, the restriction rod will notch. There is no allowance on the opposite side to the moving direction than the pin member of the engaging means in the combined state, and the movement of the control rod is regulated together with the regulating rod Ri, is shifted up operation itself is regulation, attempting to operate and the driver never feel uncomfortable.

According to the multi-stage transmission of the second aspect, the restriction rod is sandwiched between the forward rotation cam rod and the reverse rotation cam rod and is provided so as to be relatively slidable in the axial direction. The gear shafts supporting the rod and the cam rod for forward rotation and reverse rotation may be formed with a single groove that can slide in the common axial direction without providing a groove on each of them, thereby reducing the number of processing steps.
In addition, notches corresponding to the cam grooves of the two cam rods for forward rotation and reverse rotation can be provided in one regulation rod, and the number of parts can be reduced.

  According to the multi-stage transmission of the third aspect, the restriction rod is formed of a member separate from the control rod, and is coupled so as to move integrally with the control rod by the coupling means. Rather than being formed separately, the control rod and the control rod can be easily formed rather than integrally formed.

  According to the multi-stage transmission according to claim 4, the half cotter is fitted into both the fitting groove provided on the outer peripheral surface of the control rod and the fitting groove provided on the inner surface of the regulating rod. Since the restricting rod is integrally coupled to each other, the separate control rod and restricting rod can be integrally coupled with a simple coupling structure.

  According to the multi-stage transmission of claim 5, the cam rod and the regulating rod are arranged at symmetrical positions opposite to the outer periphery of the control rod, so that the movement of the control rod is controlled by the cam rod and the regulating rod. It can be transmitted to the regulating rod without any deviation, and the axis can be maintained to make the movement smooth.

It is sectional drawing of the multistage transmission which concerns on one embodiment of this invention. It is sectional drawing (II-II sectional view taken on the line of FIG. 4, FIG. 5) which shows a counter gear shaft and the structure around it. It is another sectional view (III-III line sectional view of Drawing 4 and Drawing 5) which shows a counter gear shaft and the structure around it. FIG. 4 is a sectional view taken along line IV-IV in FIGS. 2 and 3. FIG. 5 is a cross-sectional view taken along line VV in FIGS. 2 and 3. It is a disassembled perspective view of a control rod and a lost motion mechanism. FIG. 5 is an exploded perspective view of a state in which a lost motion mechanism is assembled to a control rod and a cam rod and the like. It is a perspective view of a control rod. FIG. 9 is a left side view of the regulating rod (viewed along arrow IX in FIG. 8). It is a disassembled perspective view of a part of a counter gear shaft and a pin member and a spring. FIG. 11 is a left side view of the counter gear shaft (a view taken along arrow XI in FIG. 10). It is a disassembled perspective view of a rocking claw member, a spindle pin, a pin member, and a spring. It is a perspective view which shows the state which assembled | attached a part of speed-change drive means and the engagement means to the control rod. FIG. 14 is a perspective view showing a state in which a bearing collar member is packaged on the counter gear shaft in the state shown in FIG. 13. It is explanatory drawing which shows the positional relationship of the cam rod in the 1st speed acceleration state, a control rod, and a pin member. It is explanatory drawing which shows the positional relationship of the cam rod in the 2nd speed acceleration state, a control rod, and a pin member. It is explanatory drawing which shows the positional relationship of the cam rod in the 2nd speed deceleration state, a control rod, and a pin member.

Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.
A multi-stage transmission 10 according to the present embodiment is configured to be incorporated in an internal combustion engine mounted on a motorcycle.
FIG. 1 is a cross-sectional view of the multi-stage transmission 10, and as shown in FIG. 1, the multi-stage transmission 10 is provided in an engine case 1 that is shared with an internal combustion engine.
The engine case 1 formed by combining the left engine case 1L and the right engine case 1R which are divided into left and right forms a transmission chamber 2, in which the main gear shaft 11 and the counter gear shaft 12 are parallel to each other. The shaft is supported so as to be rotatable in the left-right direction.

  The main gear shaft 11 is rotatably supported on the side wall of the left engine case 1L and the side wall 1RR of the right engine case 1R via bearings 3L and 3R, and passes through the right bearing 3R and protrudes from the transmission chamber 2 to the right end. Is provided with a multi-plate friction clutch 5.

On the left side of the friction clutch 5, a primary driven gear 4 to which rotation of a crankshaft (not shown) is transmitted is rotatably supported by the main gear shaft 11.
The rotation of the crankshaft of the internal combustion engine is transmitted from the primary driven gear 4 to the main gear shaft 11 via the engaged friction clutch 5.

  On the other hand, the counter gear shaft 12 is also rotatably supported on the side wall of the left engine case 1L and the side wall 1RR of the right engine case 1R via bearings 7L and 7R, and protrudes from the transmission chamber 2 through the left bearing 7L. An output sprocket 70 is fixed by spline fitting to the left end.

  A drive chain wound around the output sprocket 70 is wound around a sprocket that drives a rear wheel (not shown) behind, and the rotational power of the counter gear shaft 12 is transmitted to the rear wheel, so that the vehicle travels.

On the main gear shaft 11, a drive transmission gear m group is configured between the left and right bearings 3L, 3R so as to be rotatable integrally with the main gear shaft 11.
A first drive transmission gear m1 is formed integrally with the main gear shaft 11 along the right bearing 3R, and a spline formed between the first drive transmission gear m1 of the main gear shaft 11 and the left bearing 3L is viewed from the right. The second, third, fourth, fifth, and sixth drive transmission gears m2, m3, m4, m5, and m6, whose diameters are sequentially increased to the left, are spline-fitted.

On the other hand, on the counter gear shaft 12, a group of driven transmission gears n is rotatably supported via an annular bearing collar member 13 between the left and right bearings 7L and 7R.
In the counter gear shaft 12, a right end bearing collar member 13 is provided through a collar member 14R interposed to the left of the right bearing 7R, and an outer case is provided through a collar member 14L interposed to the right of the left bearing 7L. Five bearing collar members 13 are packaged at equal intervals between the bearing collar member 13 at the left end, and a total of seven bearing collar members 13 straddle between adjacent bearing collar members 13 and 13. The first, second, third, fourth, fifth, and sixth driven transmission gears n1, n2, n3, n4, n5, and n6, whose diameters are sequentially reduced from right to left, are rotatably supported. .

  The first, second, third, fourth, fifth, and sixth drive transmission gears m1, m2, m3, m4, m5, and m6 that rotate integrally with the main gear shaft 11 are rotatable on the counter gear shaft 12. The corresponding first, second, third, fourth, fifth and sixth driven transmission gears n1, n2, n3, n4, n5 and n6 are always meshed with each other.

  The meshing of the first drive transmission gear m1 and the first driven transmission gear n1 constitutes the first speed with the largest reduction ratio, and the meshing of the sixth drive transmission gear m6 and the sixth driven transmission gear n6 has the smallest reduction ratio. Sixth speed is configured, and during that period, the reduction gear ratio is gradually decreased to form second speed, third speed, fourth speed, and fifth speed.

  The counter gear shaft 12 has odd-numbered gears (first, third, and fifth driven gears n1, n3, and n5) with odd-numbered gears and even-numbered gears (second, fourth, and fourth) with even-numbered gears. 6 driven transmission gears n2, n4, n6) are alternately arranged.

  The counter gear shaft 12 having a hollow cylindrical shape is incorporated so that the engagement means 20 that can be engaged with each driven transmission gear n will be described later. There are 4 types of cam rods C (Cao, Cao, Cae, Cae, Cbo, Cbo, Cbe, Cbe) and 2 types of 2 restriction rods E and F in total. It is fitted in a cam guide groove 12g, which will be described later, formed on the hollow inner peripheral surface, and is provided so as to be movable in the axial direction.

  A control rod 51, which is one component of the speed change driving means 50 that drives the cam rod C to change the speed, is inserted into the hollow central axis of the counter gear shaft 12, and the control rod 51 moves in the axial direction. E and F are moved together, and the cam rod C is moved in the axial direction in conjunction with the lost motion mechanisms 52 and 53.

A mechanism for moving the control rod 51 in the axial direction is provided in the right engine case 1R.
The movement of the control rod 51 in the axial direction interlocks the cam rod C in the axial direction via the lost motion mechanisms 52 and 53, and the movement of the cam rod C is changed to each driven speed change by the engaging means 20 incorporated in the counter gear shaft 12. The gear n is selectively engaged with the counter gear shaft 12 for shifting.

Referring to FIG. 6, the control rod 51 of the speed change driving means 50 has a cylindrical rod shape, and is formed with a reduced diameter at the center in the axial direction to form a central recess 51c, and further reduced in diameter at two left and right positions. The outer peripheral recesses 51a and 51b are each formed over a predetermined length.
The left end portion 51aa of the control rod 51 is short, the right end is long and has a male screw end portion 51bb formed with a male screw, and a hexagonal nut portion 51n is formed in front of the male screw end portion 51bb.

The lost motion mechanisms 52 and 53 are assembled corresponding to the left and right outer peripheral recesses 51a and 51b of the control rod 51, respectively.
The left and right lost motion mechanisms 52, 53 are arranged so as to be symmetrical with respect to each other.

  The left lost motion mechanism 52 has a spring holder 52h into which a control rod 51 is slidably inserted and is configured by connecting a long holder 52hl and a short holder 52hs, and corresponds to the outer peripheral recess 51a of the control rod 51 on the inner peripheral surface. An inner peripheral recess 52ha is formed.

  When the control rod 51 is passed through the spring holder 52h and the spring holder 52h is positioned in the outer peripheral recess 51a, the inner peripheral recess 52ha of the spring holder 52h and the outer peripheral recess 51a of the control rod 51 constitute a common space. To do.

A pair of left and right cotters 52c and 52c, which are spring receivers, are fitted oppositely so as to straddle both spaces of the inner peripheral recess 52ha of the spring holder 52h and the outer peripheral recess 51a of the control rod 51, and the control is performed between the two cotters 52c and 52c. A compression coil spring 52 s wound around the rod 51 is interposed to urge both the cotters 52 c and 52 c in a separating direction.
The cotter 52c has a hollow disk shape in which the inner diameter of the inner peripheral recess 52ha of the spring holder 52h is the outer diameter, and the outer diameter of the outer peripheral recess 51a of the control rod 51 is the inner diameter. Yes.

The lost motion mechanism 53 on the right side (spring holder 53h, long holder 53hl, short holder 53hs, inner peripheral recess 53ha, cotter 53c, compression coil spring 53s) has the same structure and is disposed in the outer peripheral recess 51b of the control rod 51. The
Therefore, when the control rod 51 moves in the axial direction, the spring holders 52h, 53h move in the axial direction via the compression coil springs 52s, 53s of the left and right lost motion mechanisms 52, 53.

  Eight cam rods C (Cao, Cao, Cae, Cae, Cbo, Cbo) are provided on the outer peripheral surfaces of the spring holders 52h, 53h of the lost motion mechanisms 52, 53 attached to the left and right outer peripheral recesses 51a, 51b of the control rod 51. , Cbe, Cbe) are in contact with each other at the radiation position (see FIG. 7).

The cam rod C is a rectangular rod-like member having a rectangular cross section and extending in the axial direction. The outer peripheral side opposite to the inner peripheral side contacting the spring holders 52h, 53h forms a cam surface, and the cam surface Grooves v are formed at the required three locations, and a pair of locking claws p that locks either one of the spring holders 52h and 53h from the left and right protrude from the inner peripheral side surface.
Since the cam rod C is a rectangular prismatic member having a simple cross section and a generally simple outer shape, the cam rod C can be easily manufactured.

  The cam rods Cao, Cbo for odd-numbered stages formed with cam grooves v1, v3, v5 at three positions corresponding to the odd-numbered stage gears (first, third, fifth driven transmission gears n1, n3, n5) There are two types of rotation (rotation direction in which force is applied from the driven transmission gear n to the counter gear shaft 12 during acceleration) and reverse rotation (rotation direction in which force is applied from the driven transmission gear n to the counter gear shaft 12 during deceleration). One forward rotation odd-stage cam rod Cao has an engaging claw p that engages with the right spring holder 53h on the inner peripheral side, and the other reverse rotation odd-stage cam rod Cbo has a left spring holder 52h on the inner peripheral side. There is a locking claw p that locks to (see FIG. 7).

  Similarly, cam rods Cae for even-numbered stages formed at three positions corresponding to even-numbered gears (second, fourth and sixth driven transmission gears n2, n4, n6) with even-numbered gear grooves v2, v4, v6. , Cbe are of two types, forward rotation and reverse rotation, and one forward rotation even-stage cam rod Cae has a locking claw p that locks to the left spring holder 52h on the inner peripheral side, The reverse rotation even-stage cam rod Cbe has a locking claw p that locks to the right spring holder 53h on the inner peripheral side surface (see FIG. 7).

  Accordingly, when the control rod 51 is moved in the axial direction, the positive rotation odd-numbered cam rod Cao and the reverse-rotating even-numbered cam rod Cbe are linked in the axial direction together with the spring holder 53h via the compression coil spring 53s of the lost motion mechanism 53 on the right side. Then, the reverse rotation odd stage cam rod Cbo and the forward rotation even stage cam rod Cae are interlocked in the axial direction together with the spring holder 52h via the coil spring 52s of the left lost motion mechanism 52.

Further, as shown in FIG. 7, two kinds of restriction rods E and F are provided in such a manner that a total of four restriction rods are sandwiched between two cam rods C, respectively.
One restriction rod E is sandwiched between the forward rotation even stage cam rod Cae and the reverse rotation odd stage cam rod Cbo, and the other regulation rod F is sandwiched between the forward rotation odd stage cam rod Cao and the reverse rotation even stage cam rod Cbe. It is installed.

As shown in FIGS. 8 and 9, the regulation rods E and F have a fan shape with a narrow cross section and a long bar shape in the left-right direction, and are longer in the radial direction than the rectangular cross section of the cam rod C. The width is substantially the same and the circumferential width is large.
The regulating rod E has notches e2, e4, corresponding to the cam grooves v2, v4, v6 of the positive rotation even-numbered cam rod Cae on the side edge where the side surface and the outer peripheral surface where the positive rotation even-numbered cam rod Cae slides contact each other. e6 is formed and notches e1, e3, e3, e3, e3, e3, e3, e3, e3, e5, v5, v5, and v5 of the reverse rotation odd-numbered cam rod Cbo are formed on the side edge where the side surface and the outer peripheral surface meet. e5 is formed.

  Similarly, the regulating rod F has notches f1 corresponding to the cam grooves v1, v3, v5 of the positive rotation odd-numbered cam rod Cao on the side edge where the side surface and the outer peripheral surface where the positive rotation odd-numbered cam rod Cao slides come into contact. , F3, f5 are formed, and the side edge where the side surface where the reverse rotation even-numbered cam rod Cbe slidably contacts and the outer peripheral surface intersects with the cam grooves v2, v4, v6 of the reverse rotation even-numbered cam rod Cbe. , F4, f6.

  The cam grooves v1, v2, v3, v4, v5, and v6 are all short in the axial direction and have the same length, whereas the notches e1 and notch e6 of the regulating rod E are used except for the other notches. The notches f1, f2, f3, f4, f5, and f6 of e2, e3, e4, e5 and the restriction rod F are approximately twice as long in the axial direction as the cam groove v. The notches e1 and e6 are The axial length is substantially the same as the cam groove v.

  The regulating rod E is formed with a pair of engaging claws ep, ep that are opposed to each other with a predetermined width at a predetermined position near the center of the inner circumferential surface in the axial direction. A pair of locking claws fp and fp are formed to protrude at a predetermined position.

  As shown in FIG. 9, the regulating rods E and F are respectively sandwiched between two cam rods C (indicated by a two-dot chain line in FIG. 9), and the spring holders 52h and 53h of the left and right lost motion mechanisms 52 and 53, respectively. As shown in FIG. 7, a cotter 80 divided in half for assembly is fitted into the central recess 51c of the control rod 51, and the regulating rod E is fitted to the cotter 80. The pair of latching claws ep, ep projecting on the inner peripheral surface of the rod and the pair of latching claws fp, fp projecting on the inner peripheral surface of the regulating rod F are fitted so as to be sandwiched from the left and right, and the cotter 80 is The control rod 51 and the regulation rods E and F are connected to each other.

In addition, the retainer 81 is put on the outer peripheral surface and one side surface of the cotter 80 fitted in the central recess 51c of the control rod 51, and the lock rod E is locked with the washer 82 applied to the other side surface of the cotter 80. The control rod 51 and the regulating rod E, are fitted into the fitting groove between the claws ep and ep and the fitting groove between the locking claws fp and fp of the restriction rod F, and the retainer 81 and the washer 82 are interposed. F is joined together.
Therefore, the regulating rods E and F move in the left-right axis direction integrally with the control rod 51.

  As shown in FIG. 7, a cylindrical control rod operating element 55 is attached to the right end portion on the right side of the nut portion 51n of the control rod 51 via a ball bearing 56 fitted inside.

  Two ball bearings 56 are connected in the axial direction. The ball bearing 56 is inserted into the right end portion on the right side of the nut portion 51n of the control rod 51, and is engaged with the nut portion 51n by a nut 57 screwed into the male screw end portion 51bb. It is sandwiched and fastened.

Therefore, the control rod operator 55 holds the right end portion of the control rod 51 rotatably.
A pin hole 55h pierced in the diametrical direction is formed in a cylindrical portion extending to the right side of the nut 57 to which the control rod operating element 55 is screwed, and the shift pin 58 penetrates the pin hole 55h.

The shift pin 58 penetrated by the control rod operating element 55 is protruded at both ends with reference to FIG.
A groove 60 is formed in the guide portion 1Ra projecting to the right of the side wall 1RR of the right engine case 1R so as to be oriented in the left-right direction. The shift pin 58 is prevented from rotating by fitting.

  A support shaft 65 is implanted in the side wall 1RR so as to protrude rightward, and a shift drum 67 is rotatably supported on the support shaft 65 via a bearing 66. A shift groove 67v of the shift drum 67 is provided. The other end of the shift pin 58 is slidably fitted.

  The shift groove 67v of the shift drum 67 is formed so as to draw a spiral on the outer peripheral surface of the drum, and each gear position from the first speed to the sixth speed at every predetermined rotation angle (for example, 60 degrees) therebetween. And the neutral position is formed in the middle.

Therefore, the rotation of the shift drum 67 moves the shift pin 58 fitted in the shift groove 67v together with the control rod operator 55 in the axial direction.
Since the control rod operating element 55 holds the right end portion of the control rod 51 rotatably, the rotation of the shift drum 67 eventually moves the control rod 51 in the axial direction.

The shift drum 67 is rotated via shift transmission means (not shown) by manual operation of a shift select lever (not shown).
The shift transmission means is provided with a mechanism such as a shift cam member that stably holds the shift drum 67 at the gear position for each predetermined angle, and the operation power of the shift select lever is transmitted to a gear 67g formed on the side edge of the shift drum 67. Then, the shift drum 67 is sequentially rotated to the gear position.

  As described above, the shift drive means 50 moves in the axial direction while the shift drum 67 is rotated by manual operation of the shift select lever, and the rotation of the shift drum 67 guides the shift pin 58 fitted in the shift groove 67v. Then, the movement of the shift pin 58 moves the control rod 51 in the axial direction via the control rod operator 55, and the movement of the control rod 51 moves through the eight motion rods Cao of the engaging means 20 via the lost motion mechanisms 52 and 53. , Cao, Cae, Cae, Cbo, Cbo, Cbe, and Cbe.

The control rod 51 assembled with the lost motion mechanisms 52 and 53 is inserted into the hollow of the counter gear shaft 12 and disposed on the central shaft.
The hollow cylindrical counter gear shaft 12 has an inner diameter substantially equal to the outer diameter of the spring holders 52h and 53h of the lost motion mechanisms 52 and 53, and the spring holders 52h and 53h attached to the control rod 51 are slidably fitted. Insert.

Referring to the left side view of the counter gear shaft 12 in FIG. 11, four cam guide grooves having fan-shaped cross sections at four radial positions on the hollow inner peripheral surface of the counter gear shaft 12 at equal intervals in the circumferential direction. 12g extends in the axial direction.
The cam rod Cae for forward rotation even-numbered stages and the cam rod Cbo for reverse rotation odd-numbered stages sandwich the restriction rod E, and the cam rod Cbe for forward rotation odd-numbered odd stages and the cam rod Cbe for reverse rotation even-numbered stages sandwich the restriction rod F. It is slidably fitted into the guide groove 12g.
The same type of cam rod C and restriction rods E and F are disposed at symmetrical positions.
Therefore, the movement of the control rod 51 can be transmitted to the cam rod C and the restriction rods E and F without deviation, and the movement can be made smooth while maintaining the axis.

  The cam guide groove 12g for preventing rotation of the eight cam rods C and the four restriction rods E and F on the counter gear shaft 12 is a state in which the two cam rods C and one restriction rods E and F are bundled. Since they are fitted, four are sufficient, and the processing man-hour of the counter gear shaft 12 can be reduced.

  The cam guide groove 12g has a depth substantially equal to the radial length of the cam rod C and the regulating rods E and F. Therefore, the cam surface which is the outer peripheral side surface of the cam rod C is substantially slidably contacted with the bottom surface of the cam guide groove 12g. The side surface forms substantially the same surface as the hollow inner peripheral surface and comes into contact with the outer peripheral surface of the spring holders 52h, 53h, and the locking claw p protruding from the inner peripheral side surface holds either of the spring holders 52h, 53h from both sides.

  The counter gear shaft 12 having a hollow cylindrical shape includes a left cylindrical portion 12b and a right cylindrical portion whose outer diameters are reduced on both the left and right sides of the central cylindrical portion 12a on which the driven transmission gear n is pivotally supported via a bearing collar member 13. 12c is formed (see FIG. 10).

  The left cylindrical portion 12b is fitted with a bearing 7L via a washer 14L, and a spline 12s is partially formed to fit the output sprocket 70, while the right cylindrical portion 12c is fitted with a washer 14R. The bearing 7R is fitted (see FIGS. 1, 2 and 3).

In the hollow of the counter gear shaft 12, the inner diameter of the small-diameter inner surface where the cam guide groove 12g is formed is equal to the outer diameter of the spring holders 52h, 53h, and the inner diameters on both sides of the small-diameter inner peripheral surface are the cam guide grooves 12g. A large-diameter inner peripheral surface that forms substantially the same peripheral surface as the bottom surface is formed (see FIGS. 2 and 3).
About half of the control rod operating element 55 is inserted inside the enlarged inner diameter part on the right side.

  Thus, the control rod 51, the lost motion mechanisms 52, 53 and the eight cam rods Cao, Cao, Cae, Cae, Cbo, Cbo, Cbe, Cbe and the four regulating rods E, are inserted into the hollow of the counter gear shaft 12. When F is incorporated, all of them rotate together, and when the control rod 51 moves in the axial direction, the control rods 51 move together with the control rod 51 in the axial direction, and the coil of the left lost motion mechanism 52 The reverse rotation odd stage cam rod Cbo and the forward rotation even stage cam rod Cae are linked in the axial direction via the spring 52s, and the reverse rotation odd stage cam rod Cao and the reverse rotation even number via the coil spring 53s of the right lost motion mechanism 53. The step cam rod Cbe is interlocked in the axial direction.

  Since the lost motion mechanisms 52 and 53 are arranged in the axial direction of the counter gear shaft 12 and interposed between the outer peripheral surface of the control rod 51 and the inner surfaces of the plurality of cam rods C, the lost motion mechanisms 52 and 53 are located in the hollow of the counter gear shaft 12. The control rod 51, the lost motion mechanism 52, 53, and the cam rod C are overlapped in the radial direction to avoid the expansion of the multi-stage transmission 10 in the axial direction, and the lost motion mechanism 52, 53 can be compactly accommodated in the hollow of the counter gear shaft 12. The housing can be accommodated to reduce the size of the multi-stage transmission 10 itself.

  Two lost motion mechanisms 52 and 53 are provided on the control rod 51 in the axial direction, and each lost motion mechanism 52 and 53 is linked to another cam rod C. The cam rod C can be made to move in two different ways to make the speed change smooth, and the lost motion mechanisms 52 and 53 are made symmetrical to reduce the manufacturing cost and facilitate the management of parts during assembly. .

  As shown in FIG. 10, the central cylindrical portion 12a on which the driven transmission gear n is pivotally supported via the bearing collar member 13 of the counter gear shaft 12 has a large outer diameter and is configured to be thick. A narrow circumferential groove 12cv that goes around in the circumferential direction on the outer periphery corresponds to the first, second, third, fourth, fifth, and sixth driven transmission gears n1, n2, n3, n4, n5, and n6. In addition, six axial grooves 12av are formed at equal intervals in the axial direction, and four axial grooves 12av oriented in the axial direction are formed at equal intervals in the circumferential direction.

  Further, on the outer peripheral portion of the central cylindrical portion 12a of the counter gear shaft 12, four portions defined by four axial grooves 12av are adjacent to each other in the circumferential direction. A long rectangular recess 12p that is elongated equally between the grooves 12av and 12av in the left and right direction, and a short length in which the groove width of the circumferential groove 12cv is evenly enlarged in the left and right directions in part between the adjacent axial grooves 12av and 12av. Rectangular recesses 12q are alternately formed in the axial direction.

Spring receiving portions 12d and 12d are formed in two axially elongated oval shapes in the axial direction and slightly recessed over the circumferential groove 12cv at two locations on the bottom surface of the long rectangular recess 12p.
Further, a pin hole 12h is formed in the radial direction up to the cam guide groove 12g on the circumferential groove 12cv at a thick portion between the short rectangular recess 12q and the axial groove 12av.

That is, the pin hole 12h is drilled in the radial direction of the cam guide groove 12g engraved at four locations in the circumferential direction from the hollow inner peripheral surface of the counter gear shaft 12.
Four pin holes 12h are formed on each circumferential groove 12cv.

The spring receiving portion 12d is provided with a compression spring 22 wound in an elliptical shape with its end fitted.
A pin member 23 is slidably inserted into the pin hole 12h.

Each cam guide groove 12g is slidably fitted in a bundle with two regulating rods E (F) and two cam rods C so as to sandwich the regulating rod E (F), so that it is fitted into the pin hole 12h. The pin member 23 is in contact with the cam surface of the corresponding cam rod C and the outer peripheral surface of the restriction rod E (F) at the center end, and the cam groove v and the notch e are moved by the movement of the cam rod C and the restriction rod E (F). When (f) corresponds to the pin hole 12h, the pin member 23 falls into the cam groove v and the notch e (f), and when the sliding contact surface other than the cam groove v and the outer peripheral surface other than the notch e (f) correspond, the pin The member rides on the sliding contact surface and the outer peripheral surface, and moves forward and backward by the movement of the cam rod C and the regulating rod E (F).
The advancement and retraction of the pin member 23 in the pin hole 12h causes the distal end portion of the pin member 23 to protrude outward from the bottom surface of the circumferential groove 12cv.

The swinging claw member R is formed in the circumferential groove 12cv that communicates between the long rectangular recess 12p and the short rectangular recess 12q formed on the outer peripheral portion of the central cylindrical portion 12a of the counter gear shaft 12 having the above-described structure. Is embedded, and a support pin 26 is embedded in the axial groove 12av to pivotally support the swing claw member R.
FIG. 13 shows a state where all the swinging claw members R are assembled in this manner.

  In the exploded perspective view of FIG. 12, it is embedded in the circumferential groove 12cv, the long rectangular recess 12p, and the short rectangular recess 12q corresponding to the odd-stage gears (first, third, and fifth driven transmission gears n1, n3, and n5). Four oscillating claw members R, and circumferential grooves 12cv and long rectangular recesses 12p corresponding to even-numbered even gears (second, fourth and sixth driven transmission gears n2, n4, n6), The four swinging claw members R embedded in the short rectangular recess 12q are illustrated in a posture maintaining the relative angular positional relationship with each other, and in addition, a support pin that pivotally supports each swinging claw member R. 26 and a compression spring 22 and a pin member 23 acting on each swing claw member R are shown.

  The swinging claw members R are all of the same shape, have a substantially arc shape when viewed in the axial direction, and the outer peripheral portion of the through hole through which the support shaft pin 26 penetrates in the center lacks the bearing recess Rd. A wide rectangular engagement claw Rp is formed on one side with respect to the swing center of the bearing recess Rd, and a narrow pin receiving portion Rr extends on the other side. A wide end portion Rq that is widened is formed.

In the swing claw member R, the pin receiving portion Rr is slidably fitted in the circumferential groove 12cv in which the pin hole 12h is formed, and one engagement claw portion Rp is swingable in the long rectangular recess 12p. The bearing recess Rd is fitted to the axial groove 12av and the other wide end Rq is fitted to the short rectangular recess 12q.
Then, the support pin 26 is fitted into the matched bearing recess Rd and the axial groove 12av.

  The swinging claw member R is formed symmetrically with respect to the circumferential groove 12cv to be fitted, and one wide rectangular engagement claw Rp is heavier than the other pin receiving part Rr and the wide end Rq, When the pin 26 is pivotally supported and rotates together with the counter gear shaft 12, the swinging claw member R swings so that the engaging claw Rp acts as a weight against the centrifugal force and protrudes in the centrifugal direction.

The swinging claw member R is formed such that the pin receiving portion Rr is narrower than the engaging claw Rp side on the opposite side with respect to the swinging center.
Further, since the pin receiving portion Rr only needs to have a width sufficient to receive the pin member 23, the swinging claw member R can be formed in a small size, and the other engaging claw portion Rp can be swung by the centrifugal force. The movement can be facilitated.

  Since the swinging claw members R adjacent to each other in the circumferential direction are assembled to the counter gear shaft 12 in a symmetrical attitude, the engaging claw portions Rp, Rp facing each other with a predetermined interval are the same long rectangular recess 12p. The other wide end Rq adjacent to each other is fitted into a common short rectangular recess 12q.

  A compression spring 22 supported at one end by a spring receiving portion 12d of the counter gear shaft 12 is interposed inside the engaging claw portion Rp of the swing claw member R, and is inserted into the pin hole 12h inside the pin receiving portion Rr. The pin member 23 is interposed between the cam rod C and the pin member 23.

  In this way, the swing claw member R is pivotally supported by the support pin 26 and is embedded in the long rectangular recess 12p, the short rectangular recess 12q, and the circumferential groove 12cv of the counter gear shaft 12, The engaging claw Rp of the compression spring 22 is urged outward by the compression spring 22, and the other pin receiving portion Rr is pressed by the advancement and retraction of the pin member 23. The swinging claw member R swings against the force.

When the pin member 23 advances in the centrifugal direction and swings the swinging claw member R, the swinging claw member R has the engagement claw portion Rp submerged in the long rectangular recess 12p and the central cylinder of the counter gear shaft 12 There is nothing that protrudes outward from the outer peripheral surface of the portion 12a.
When the pin member 23 is retracted, the engaging claw portion Rp urged by the compression spring 22 to act on the centrifugal force projects outward from the outer peripheral surface of the central cylindrical portion 12a of the counter gear shaft 12, and the driven transmission gear n Engageable.

  Since the compression spring 22 is interposed between the inner side surface of the engaging claw Rp of the swing claw member R and the long rectangular recess 12p of the counter gear shaft 12, the space dedicated to the spring is not required in the axial direction. The size of the counter gear shaft 12 in the axial direction can be avoided, and the compression spring 22 is arranged in the center of the axial width of the swing claw member R so that the swing claw member R itself is disposed on both sides in the axial direction. Two types of swinging claw members that can be formed symmetrically and thus engaged and disengaged in both directions of the relative rotational direction of the driven transmission gear n and the counter gear shaft 12 are the same shape of the swinging claw member R. It is not necessary to prepare swinging claw members having different shapes.

  The compression spring 22 has an elliptical shape whose major axis is the axial direction of the counter gear shaft 12. The elliptical compression spring 22 has a major axis larger than the width of the pin receiving portion Rr of the swinging claw member R, and the pin receiving portion Rr. Since the counter gear shaft 12 can be easily machined and the swinging claw member R can be stabilized stably. The counter gear shaft 12 can be assembled.

  Four swinging claw members R corresponding to odd-numbered gears (first, third, and fifth driven transmission gears n1, n3, and n5) and even-numbered gears (second, fourth, and sixth driven gears) The four swinging claw members R corresponding to the transmission gears n2, n4, n6) are in a relative angular position relationship rotated 90 degrees around the axis.

  Four swinging claw members R corresponding to the odd-numbered gears (first, third, and fifth driven transmission gears n1, n3, and n5) are in contact with each other in the forward rotation direction of the gear, and each odd-stage driven transmission gear n1. , N3, n5 and the counter gear shaft 12 are engaged with each other so as to rotate in synchronization with each other, and the odd-numbered driven gears n1, n3 are in contact with each other in the reverse rotation direction of the gear. , N5 and counter gear shaft 12 are provided with a pair of counter-rotating odd-numbered engaging members Rbo that are engaged so as to rotate in synchronization with each other at symmetrical positions.

  Similarly, the four swinging claw members R corresponding to the even-numbered gears (second, fourth, and sixth driven transmission gears n2, n4, and n6) are brought into contact with each other in the forward rotation direction of the gears, and each even-numbered gear is driven. A forward rotation even-numbered-stage swinging claw member Rae engaged so that the transmission gears n2, n4, n6 and the counter gear shaft 12 rotate in synchronization with each other, and the even-numbered driven gears in contact with each other in the reverse rotation direction of the gear. A pair of counter-rotating even-numbered engaging members Rbe that are engaged so that n2, n4, and n6 and the counter gear shaft 12 rotate synchronously are provided in pairs at symmetrical positions.

The forward rotation odd-stage swinging claw member Rao is swung by the pin member 23 that moves forward and backward by the movement of the forward-rotation odd-stage cam rod Cao, and the reverse-rotation odd-stage engagement member Rbo is moved by the reverse-rotation odd-stage cam rod Cbo. It swings by the pin member 23 that advances and retreats by
Similarly, the forward rotating even-stage swinging claw member Rae is swung by the pin member 23 that moves forward and backward by the movement of the forward-rotating even-numbered cam rod Cae, and the reverse-rotating even-numbered engaging member Rbe is the reverse-rotating even-numbered cam rod. The pin member 23 is moved back and forth by the movement of Cbe to swing.

  When the engagement means 20 is incorporated in the counter gear shaft 12, first, the right end bearing collar member 13 is externally mounted on the outer peripheral end of the central cylindrical portion 12a, and the support pin 26 is inserted into the axial groove 12av inside the bearing collar member 13. The right end engaging means 20 is incorporated so that one end of the shaft is inserted, and the next bearing collar member 13 is packaged so as to cover the other end of the support pin 26, and then the next stage engagement is performed in the same manner as the previous stage. The incorporation of the combining means 20 is sequentially repeated, and finally the bearing collar member 13 at the left end is packaged to finish.

As shown in FIG. 14, the bearing collar member 13 is packaged in an axial position other than the long rectangular recess 12p and the short rectangular recess 12q of the central cylindrical portion 12a, and is continuously embedded in a line in the axial groove 12av. The support pin 26 is disposed across the adjacent support pins 26 and 26 to prevent the support pin 26 and the swinging claw member R from falling off.
Since the support pin 26 embedded in the axial groove 12av of the central cylindrical portion 12a of the counter gear shaft 12 is embedded at a depth in contact with the outer peripheral surface of the central cylindrical portion 12a, when the bearing collar member 13 is sheathed. It is fixed without play.

  The forward rotation odd-numbered swinging claw member Rao (forward rotation even-numbered swinging claw member Rae) and the reverse rotation odd-numbered step engagement member Rbo (reverse rotation even-numbered step engagement member Rbe) Rp and Rp are extended, and the positive rotation odd-numbered swinging claw member Rao (positive rotation even-numbered swinging claw member Rae) is an engagement convex portion in the positive rotation direction of the driven transmission gear n (and the counter gear shaft 12). The reverse rotation odd-numbered engagement member Rbo (reverse rotation even-numbered engagement member Rbe) contacts and engages the engagement convex portion 31 in the reverse rotation direction of the driven transmission gear n. To do.

  It should be noted that the forward rotation odd-numbered swinging claw member Rao (forward rotation even-numbered swinging claw member Rae) is not engaged in the reverse rotation direction of the driven transmission gear n even if the engagement claw portion Rp protrudes to the outside. In addition, the reverse rotation odd-numbered engagement member Rbo (reverse rotation even-numbered engagement member Rbe) is not engaged in the forward rotation direction of the driven transmission gear n even if the engagement claw Rp protrudes outward.

  If the cam rod C is in the neutral position, all the driven transmission gears n are projected from the inner side by the pin member 23 protruding from the inside by the pin member 23 projecting according to the moving position of the cam rod C of the corresponding engagement means 20 respectively. In the disengaged state in which the push-up engagement claw Rp is retracted inward, it rotates freely with respect to the counter gear shaft 12.

  On the other hand, the pin member 23 enters the cam groove v (and the notches e and f of the regulating rods E and F) by the movement position of the engagement means 20 other than the neutral position of the cam rod C, and the swing claw member R swings. When the engaging claw portion Rp protrudes outward, the engaging convex portion 31 of the corresponding driven transmission gear n comes into contact with the engaging claw portion Rp, and the rotation of the driven transmission gear n is counted as a counter. The rotation of the counter gear shaft 12 is transmitted to the driven transmission gear n.

  In the shift drive means 50, the shift drum 67 is rotated by a predetermined amount by manual operation of the shift select lever, and the rotation of the shift drum 67 is moved in the axial direction via the shift pin 58 fitted in the shift groove 67v. It moves by a predetermined amount and interlocks the eight cam rods Cao, Cao, Cae, Cae, Cbo, Cbo, Cbe, Cbe of the engaging means 20 through the lost motion mechanisms 52, 53.

  As the cam rod C (and the regulating rods E and F) move in the axial direction, the pin member 23 slidably contacting the cam surface of the cam rod C moves into and out of the cam groove v, and moves back and forth. The shift is performed by swinging and releasing the engagement with the driven transmission gear n and changing the driven transmission gear n engaged with the other driven transmission gear n and engaged with the counter gear shaft 12.

The power of the internal combustion engine is transmitted to the main gear shaft 11 through the friction clutch 5, and the first, second, third, fourth, fifth and sixth drive transmission gears m1, m2, m3, m4, m5 , M6 are integrally rotated, and the first, second, third, fourth, fifth, and sixth driven transmission gears n1, n2, n3, n4, n5, and n6, which are always meshed with them, are respectively connected. It is rotating at the rotation speed.
2 to 5 show the first speed state. In FIG. 4, the first driven transmission gear n1 rotates in the direction of the arrow, and in FIG. 5, the second driven transmission gear n2 rotates in the direction of the arrow. The second driven transmission gear n2 rotates at a higher speed than the first driven transmission gear n1.

FIG. 15 is an explanatory diagram showing the positional relationship between the cam rods Cae, Cbo, Cao, Cbe, the regulating rods E, F, and the pin member 23 in the first speed acceleration state (a state where the power from the internal combustion engine is transmitted). is there.
To shift up, the control rod 51 is moved to the right. To shift down, the control rod 51 is moved to the left. As the control rod 51 moves, the control rods E and F move together and the cam rod. Cae, Cbo, Cao, and Cbe are also linked through the lost motion mechanisms 52 and 53.

As shown in FIG. 15, in the state where the first gear is established, the notches e2 and e4 of the regulating rod E corresponding to the cam grooves v2 and v4 of the cam rod Cae for forward rotation even-numbered stages are respectively from the cam grooves v2 and v4. Also, it is formed long on the left side opposite to the right side, which is the moving direction of the control rod 51 when shifting up.
Similarly, the notches f1, f3, f5 of the restriction rod F corresponding to the cam grooves v1, v3, v5 of the positive rotation odd-numbered cam rod Cao are the control rods at the time of upshifting than the cam grooves v1, v3, v5, respectively. It is formed in a long shape on the left side opposite to the right side which is the moving direction of 51.

  On the other hand, the notches e3 and e5 of the regulating rod E corresponding to the cam grooves v3 and v5 of the reverse rotation odd-numbered cam rod Cbo are the left direction which is the moving direction of the control rod 51 at the time of downshifting than the cam grooves v3 and v5, respectively. The notches f2, f4, f6 of the regulating rod F, which are formed to be elongated on the right side opposite the direction and corresponding to the cam grooves v2, v4, v6 of the reverse rotation even-numbered cam rod Cbe, It is formed longer than v4 and v6 on the right side opposite to the left, which is the moving direction of the control rod 51 at the time of downshifting.

  Note that the notch e1 and the notch e6 of the restriction rod E have a short width substantially the same as the cam groove v1 of the corresponding reverse-rotation odd-numbered cam rod Cbo and the cam groove v6 of the forward-rotation even-numbered cam rod Cae, respectively. It has become.

Although the regulating rods E and F and the cam rod C slide relative to each other in the left-right axial direction, the corresponding cam groove v of the cam rod C can be positioned within the width of the notches of the regulating rods E and F.
When the pin member 23 having an outer diameter larger than the width of the cam rod C enters the cam groove v of the cam rod C and dies, the pin member 23 enters the notches of the regulating rods E and F at the same time.

In the first speed acceleration state shown in FIG. 15, the pin member 23 is inserted into the cam groove v1 of the forward rotation odd-numbered cam rod Cao and the cam groove v1 of the reverse rotation odd-numbered cam rod Cbo, and at the same time the cutting of the restriction rod E The same pin member 23 is contained in the notch e1 and the notch f1 of the regulating rod F.
The other pin members 23 do not fall into the cam groove v of the cam rod C, but protrude in contact with the sliding contact surface of the cam rod C.

  That is, only the pin member 23 of the engaging means 20 corresponding to the first driven transmission gear n1 is in the cam grooves v1 and v1 of the odd-numbered cam rods Cao and Cbo (see FIG. 2). The odd-numbered swinging claw members Rao and Rbo project the engaging claws Rp and Rp to the outside, and the odd-numbered swinging claw members Rao and Rbo of the odd-numbered swinging claw members Rao and Rbo The engaging convex portion 31 of the first driven transmission gear n1 rotating in Rp is engaged (see FIG. 4), and the counter gear shaft 12 is rotated together with the first driven transmission gear n1 at the same rotational speed as the first driven transmission gear n1. It is rotating.

In this first speed acceleration state, in the second driven transmission gear n2, the pin member 23 of the corresponding engagement means 20 protrudes from the cam groove v2 of the even-numbered cam rods Cae and Cbe (see FIG. 3), Since the even-numbered swinging claw members Rae and Rbe of the combining means 20 have retracted the engaging claw Rp inside, they are idle.
The other third, fourth, and fifth driven transmission gears n3, n4, n5, and n6 are similarly idle (see FIGS. 2 and 3).

It is the positive rotation odd-stage swinging claw member Rao that is engaged with the engagement convex portion 31 of the first driven transmission gear n1 and transmits the power, and receives the power of the first driven transmission gear n1. There is a considerably large frictional resistance to swing the forward rotation odd-numbered swinging claw member Rao with the protrusion of the pin member 23 to release the engagement, and it is difficult to protrude the pin member 23. Is in a state where the outer end is pressed by the positive rotation odd-numbered-stage swinging claw member Rao in a state where it has fallen into the cam groove v1 of the positive-rotation odd-numbered-stage cam rod Cao and the notch f1 of the regulating rod F (see FIG. 15).
In FIG. 15 and FIG. 16, a lattice hatch is applied to the pin member 23 in a state in which the protrusion is pressed down by the swinging claw member R.

The movement of the cam rod C in which the pin member 23 whose protrusion has been pressed into the cam groove v and the regulation rods E and F in the notches e and f are regulated by the pin member 23 is regulated.
Therefore, in the first speed acceleration state shown in FIG. 15, the positive rotation odd-numbered cam rod Cao in which the pin member 23 whose protrusion has been pressed enters the cam groove v1 is restricted from moving in any direction in the left-right axis direction. .

Further, the movement of the restriction rod F in which the same pin member 23 enters the notch f1 is also restricted, but the notch f1 is longer than the cam groove v1, and as shown in FIG. Since the notch f1 is longer to the left in the axial direction than the cam groove v1, the movement of the restriction rod F is restricted to the left, but is allowed to move a predetermined distance to the right.
That is, the control rod 51 coupled to the restriction rod F via the cotter 80 is restricted from moving to the left, but allowed to move a predetermined distance to the right.

When shifting from the first speed to the second speed in the accelerated state, the shift drum 67 is rotated by the manual operation of the shift select lever and the control rod 51 is moved to the right in the axial direction. Since the control rod 51 is allowed to move to the right, it can easily move to the right.
Note that manual operation of the shift select lever that shifts down from the first speed acceleration state is not possible because the control rod 51 is restricted from moving leftward.

When the control rod 51 moves to the right in the axial direction from the acceleration state of the first speed, the eight cam rods Cao, Cao, Cae, Cae, Cbo, Cbo, Cbe are passed through the coil springs 52s, 53s of the lost motion mechanisms 52, 53. , Cbe to move to the right in the axial direction, but the positive rotation odd-numbered cam rod Cao has a positive rotation odd-numbered swing claw member Rao that operates via the pin member 23, and the first driven transmission gear n1. Since it is engaged with the engaging projection 31 of the first gear and receives power from the first driven transmission gear n1, the frictional resistance is large enough to swing and release the positive rotation odd-numbered swinging claw member Rao. The reverse rotation even-numbered cam rod Cbe remains stopped, but the forward rotation even-numbered cam rod Cae and the reverse rotation odd-numbered cam rod Cbo move without resistance.
By the movement of the reverse rotation odd-numbered cam rod Cbo, the first-speed reverse rotation odd-numbered swinging claw member Rbo retracts the engaging claw Rp inward.

By the movement of the positive rotation even-numbered cam rod Cae, the pin member 23 enters the cam groove v2, so that the positive rotation even-numbered swing claw member Rae corresponding to the second driven transmission gear n2 has the biasing force and engagement of the compression spring 22. The engaging claw portion Rp is swung by the centrifugal force of the claw portion Rp and protrudes to the outside, can be engaged with the second driven transmission gear n2, and rotates at a higher speed than the counter gear shaft 12 that rotates together with the first driven transmission gear n1. The engaging convex portion 31 of the second driven transmission gear n2 that catches up comes into contact with the engaging claw portion Rp that protrudes to the outside of the forward rotation even-stage swinging claw member Rae.

Immediately after this, the counter gear shaft 12 starts to rotate at the same rotational speed as that of the second driven transmission gear n2 by the second driven transmission gear n2 rotating at a higher speed, and is positively moved from the engagement convex portion 31 of the first driven transmission gear n1. The engaging claw portion Rp of the rotating odd-numbered swinging claw member Rao is released, and the actual upshift from the first speed to the second speed is executed.

  When the engagement claw Rp of the positive rotation odd-numbered swinging claw member Rao is separated from the engagement convex portion 31 of the first driven transmission gear n1, the frictional resistance for fixing the positive rotation odd-numbered swinging claw member Rao is eliminated. The positive rotation odd-numbered cam rod Cao urged by the coil spring 53s of the lost motion mechanism 53 moves backward and the pin member 23 that has entered the cam groove v1 comes out and swings in the positive rotation odd-numbered step. The claw member Rao is swung and the engagement claw portion Rp is retracted inward.

  As described above, when shifting up from the first-speed acceleration state to the second-speed state in which the reduction ratio is one step smaller, the engagement convex portion 31 of the first driven transmission gear n1 is moved in the positive rotation odd-numbered swing claw member Rao. The engaging convex portion of the second driven transmission gear n2 that rotates at a higher speed while the counter gear shaft 12 rotates at the same speed as the first driven transmission gear n1 by contacting and engaging with the engaging claw Rp. Since the counter 31 catches up with the engagement claw Rp of the forward rotation even-numbered swing claw member Rae and rotates the counter gear shaft 12 at a higher speed together with the second driven transmission gear n2, the first driven transmission gear is shifted. Since the engaging claw Rp of the positive rotation odd-numbered swinging claw member Rao is separated from the engaging convex portion 31 of n1 naturally and the engagement is smoothly released, a force is not required for releasing the engagement smoothly. Operates and can perform smooth upshifts.

  Similarly, each shift-up from 2nd to 3rd, 3rd to 4th, 4th to 5th, and 5th to 6th is performed with the driven transmission gear n engaged with the swinging claw member R. Since the driven transmission gear n with a reduction ratio of one step is engaged with the swinging claw member R and shifted up, no force is required to release the engagement and the clutch is not required for shifting. In addition, there is no loss in the switching time at the time of upshifting, there is no loss of driving force, and the shift shock is small, so that smooth upshifting can be performed.

Similarly, in the downshift, the driven claw member R is engaged with the driven transmission gear n whose gear ratio is one step larger while the driven transmission gear n is engaged with the swing claw member R, and the downshift is performed. Therefore, no force is required for disengagement, it operates smoothly and does not require a clutch for shifting, there is no loss in switching time at the time of downshifting, there is no loss of driving force, and the shift shock is small Smooth downshifting can be done.

FIG. 16 shows the positional relationship between the cam rod C, the control rods E and F, and the pin member 23 in the second speed acceleration state. The pin member 23 of the engaging means 20 corresponding to the second driven transmission gear n2 is Simultaneously with the cam groove v2 of the rotating even-numbered cam rod Cae and the cam groove v2 of the reverse-rotating even-numbered cam rod Cbe, the same pin member 23 becomes the notch e2 of the regulating rod E and the notched f2 of the regulating rod F. Is also included.
The other pin members 23 do not fall into the cam groove v of the cam rod C, but protrude in contact with the sliding contact surface of the cam rod C.

  It is the positive rotation even-numbered-step swing claw member Rae that is engaged with the engagement convex portion 31 of the second driven transmission gear n2 and transmits the power, and operates the same positive-turn even-numbered swing claw member Rae. The pin member 23 (the pin member 23 provided with the lattice hatching in FIG. 16) has the outer end rotated forward evenly in a state where it has fallen into the cam groove v2 of the positive rotation even-numbered cam rod Cae and the notch e2 of the regulating rod E. It is in a state of being pressed down by the step swinging claw member Rae.

Therefore, the movement of the forward rotation even-numbered cam rod Cae in which the pin member 23 whose protrusion has been pressed enters the cam groove v2 is restricted in both the left and right axial directions.
Further, the movement of the regulating rod E in which the same pin member 23 enters the notch e2 is also restricted, but the notch e2 is longer than the cam groove v2, and in the second speed state, as shown in FIG. Since e2 is longer to the left in the axial direction than the corresponding cam groove v2, the movement of the restriction rod E is restricted to the left, but is allowed to move a predetermined distance to the right.

That is, the control rod 51 coupled to the restriction rod E is restricted from moving to the left, but is allowed to move a predetermined distance to the right.
Therefore, if the shift select lever is manually operated to shift up from the 2nd speed to the 3rd speed in an accelerating state, the control rod 51 is allowed to move rightward, so that it can be operated smoothly and shifts to the 3rd speed. be able to.

  However, if you are in the 2nd speed acceleration state and want to shift down to the 1st speed, even if you manually operate the shift select lever and move the control rod 51 to the left in the axial direction, Since the leftward movement is restricted, the movement cannot be made. Therefore, the manual operation of the shift select lever itself is restricted.

Originally, in the second speed acceleration state, the state where the second driven transmission gear n2 is engaged with the positive rotation even-numbered cam rod Cae is maintained, so even if a downshift operation is performed, the second driven transmission gear n2 The first driven transmission gear n1 that is slow in rotation does not engage with the positive rotation even-numbered cam rod Cae, and therefore it is not possible to shift to the first speed while maintaining the engagement state of the second speed.
As described above, the driver feels uncomfortable because the control rod 51 can be moved to the left and the operation of the shift select lever can be operated without being restricted even though the downshift is not possible in the acceleration state. is what happened.
Also, nothing happens when shifting down while accelerating, but then when shifting to deceleration, shifting down occurs, and the driver feels uncomfortable with this movement.
In order to avoid such a situation, in the case of the present multi-stage transmission, since the manual operation of the shift select lever for downshifting in the acceleration state is restricted, the driver does not feel uncomfortable.

FIG. 17 shows a second-speed deceleration state (a state where power from the drive wheel side is transmitted), and the pin member 23 provided with the lattice hatching is different from the second-speed acceleration state of FIG. .
That is, it is the reverse rotation even-stage swing claw member Rbe that transmits the power from the drive wheel side (counter gear shaft 12) to the second driven transmission gear n2, and the reverse rotation even-stage swing claw member. The pin member 23 for actuating Rbe (the pin member 23 provided with the lattice hatching in FIG. 17) falls into the cam groove v2 of the reverse rotation even-numbered cam rod Cbe and the notch f2 of the regulating rod F. Is pressed by the reverse rotation even-stage swinging claw member Rbe.

Accordingly, the movement of the regulating rod F in which the pin member 23 whose protrusion has been pressed is entered into the notch f2 is restricted, but the notch f2 is longer than the cam groove v2, and FIG. As shown, the notch f2 is longer to the right in the axial direction than the corresponding cam groove v2, so that the movement of the restriction rod F is restricted to the right but allowed to move a predetermined distance to the left. .
That is, the control rod 51 coupled to the restriction rod F is restricted from moving to the right, but allowed to move a predetermined distance to the left.

  Therefore, if the shift select lever is manually operated to shift down from the 2nd speed to the 1st speed, the control rod 51 is allowed to move to the left, so that it can be operated smoothly and shifts to the 1st speed. be able to.

  However, if you try to shift up to the 3rd speed when you are in the 2nd speed deceleration state, even if you try to move the control rod 51 to the right in the axial direction by manually operating the shift select lever, Since the rightward movement is restricted, the rightward movement is not possible, so that the manual operation of the shift select lever itself is restricted.

  The first speed and the second speed state have been described above, but the same applies to other shift speeds. When a certain shift speed is established, downshifting during acceleration and upshifting during deceleration are performed by the driver's shift operation. By restricting itself so that it cannot be operated, the driver does not feel uncomfortable.

  The restriction rods E and F are sandwiched between the forward rotation cam rod C and the reverse rotation cam rod C so as to be slidable in the axial direction, and are fitted into the cam guide groove 12g of the counter gear shaft 12 in the bundle state. Therefore, there is no need to provide each of the guide grooves 12g, and the number of processing steps for the counter gear shaft 12 can be reduced.

  In addition, notches e and f corresponding to the cam grooves v of the two cam rods C for forward rotation and reverse rotation can be provided in the single restriction rods E and F, thereby reducing the number of parts. can do.

  Since the control rods E and F are formed as separate members from the control rod 51 and are coupled to move together with the control rod 51 by the coupling means of the cotter 80, the control rods E and F and the control rod 51 are separately provided. It is formed and can be easily formed rather than integrally forming the control rods E and F and the control rod 51.

m: drive transmission gear, m1 to m6 ... first to sixth drive transmission gears,
n: driven transmission gear, n1 to n6: first to sixth driven transmission gears,
10 ... multi-speed transmission, 11 ... main gear shaft, 12 ... counter gear shaft, 13 ... bearing collar member,
20 ... engaging means, 22 ... compression spring, 23 ... pin member, 26 ... spindle pin,
31 ... engaging protrusion,
C ... Cam rod, Cao ... Forward rotation odd-numbered cam rod, Cae ... Forward rotation even-numbered cam rod, Cbo ... Reverse rotation odd-numbered cam rod, Cbe ... Reverse rotation even-numbered cam rod, p ... Locking claw, v1, v2, v3, v4, v5, v6 ... cam groove,
E ... Restriction rod, e, e1, e2, e3, e4, e5, e6 ... Notch,
F: restriction rod, f, f1, f2, f3, f4, f5, f6 ... notch,
R ... swinging claw member, Rao ... forward rotation odd-numbered swinging claw member, Rae ... forward rotation even-numbered swinging claw member, Rbo ... reverse rotation odd-numbered swinging claw member, Rbe ... reverse rotation even-numbered swinging claw member , Rp ... engaging claw, Rr ... pin receiving part, Rq ... wide end,
50: Variable speed drive means, 51: Control rod, 51a, 51b ... Outer peripheral recess, 52, 53 ... Lost motion mechanism, 52h, 53h ... Spring holder, 52ha, 53ha ... Inner peripheral recess, 52s, 53s ... Coil spring, 55 ... Control rod operator, 56 ... ball bearing, 57 ... nut, 58 ... shift pin, 59 ... engagement pin, 60 ... groove, 65 ... support shaft, 66 ... bearing, 67 ... shift drum, 67v ... shift groove, 70 ... Output sprocket, 80 ... cotter.

Claims (5)

A plurality of drive gears and driven gears are respectively supported by gear shafts that are parallel to each other in a constantly meshing state for each shift stage, and a plurality of gears of the drive gear and the driven gear are fixed to the gear shaft, In the multi-stage transmission that is provided between the gear and the gear shaft and that engages with each other and is switched and driven by the speed change drive means to perform speed change,
The engaging means is for forward rotation and reverse rotation that can be engaged only in each rotation direction of the forward rotation in which the power from the internal combustion engine of the gear is transmitted and the reverse rotation in which the power from the drive wheel is transmitted. There are two types of engagement means,
Each engaging means includes
An engagement convex portion provided with an engagement surface in the circumferential direction at a plurality of positions in the circumferential direction of the inner peripheral surface of each gear;
An engagement member which is provided so as to be able to protrude and retract on the gear shaft and engages and disengages with the engagement convex portion of each gear;
A plurality of cam rods supported by the gear shaft so as to be slidable in the axial direction and having a plurality of cam grooves formed on a sliding contact surface at a required position in the axial direction;
A sliding contact surface of a cam rod that is radially inserted into a required portion of the gear shaft and moves in the axial direction, and a pin member that moves forward and backward alternately to the cam groove to operate the engagement member;
The speed change driving means comprises:
A control rod provided on the hollow central shaft of the gear shaft inside the plurality of cam rods;
A lost motion mechanism that is interposed between an outer peripheral surface of the control rod and inner surfaces of the plurality of cam rods and that interlocks with the control rod via a spring that acts on each cam rod in the axial direction;
A restriction rod that moves integrally with the control rod is provided on the gear shaft in sliding contact with the cam rod,
The regulating rod is formed with a notch capable of engaging the pin member together with the cam groove of the cam rod in sliding contact with each cam groove,
The notch of the restriction rod corresponding to the cam groove of the cam rod for forward rotation is formed longer on the side opposite to the movement direction of the control rod at the time of upshifting than the cam groove in the gear position established state,
The notch of the restricting rod corresponding to the cam groove of the cam rod for reverse rotation is formed longer on the opposite side of the moving direction of the control rod at the time of downshifting than the cam groove in the gear position established state. Multi-stage transmission characterized by   The multi-stage transmission according to claim 1, wherein the restriction rod is provided between the forward rotation cam rod and the reverse rotation cam rod so as to be relatively slidable in the axial direction. .   3. The multi-stage transmission according to claim 1, wherein the restriction rod is formed of a member separate from the control rod, and is coupled so as to move integrally with the control rod by coupling means. . The coupling means is a half cotter;
The half cotter is fitted into both the fitting groove provided on the outer peripheral surface of the control rod and the fitting groove provided on the inner surface of the restriction rod, and the restriction rod is integrally coupled to the control rod. 4. The multi-stage transmission according to claim 3, wherein   5. The multistage according to claim 1, wherein the cam rod and the regulating rod are arranged in symmetrical positions opposite to each other on the outer periphery of the control rod. transmission.

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