Power unit for saddle-type vehicle

In a power unit for a saddle-type vehicle a locking pin on a shift drum side is fixed to a shift spindle and a detection shaft of a shift position sensor is interlocked and connected with the shift drum, the friction surface between the shift arm and the locking pin is reduced with suppression of the lowering of the rigidity of the shift arm to enable smooth gear shifting. An engagement hole in a shift arm allows insertion and engagement of a locking pin and has an elongated hole shape extending along one diameter line of a shift spindle. An insertion hole in the shift arm has an arc shape centered at the center axis line of the shift spindle to allow insertion of an interlocking shaft coaxially connected to the shift drum to be incapable of rotation relative to it.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2013-071742 filed Mar. 29, 2013 the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a power unit for a saddle-type vehicle in which gear trains of a plurality of shift stages one of which is selectively established according to the rotation of a shift drum are provided in a power train system between a drive source that exerts a driving force and a drive wheel. A change mechanism that rotates the shift drum includes a shift spindle that rotates according to the input of a gear shifting operating force and a shift arm that engages with a locking pin provided on the shift drum side and is fixed to the shift spindle. A detection shaft of a shift position sensor that detects the rotational position of the shift drum is interlocked and connected with the shift drum.

2. Description of Background Art

Such a power unit for a saddle-type vehicle is known. See, for example, Japanese Patent Laid-Open No. 2011-196433. In this power unit, an interlocking shaft coaxial with the rotational axis line of the shift drum is disposed so as to penetrate the shift arm in order to be interlocked and connected with the shift position sensor. Because the shift arm swings, an insertion hole with an arc shape for allowing the interlocking shaft to penetrate therethrough is made in the shift arm. The insertion hole is larger than the interlocking shaft in size. Meanwhile, the shift arm is engaged with the locking pin on the shift drum side, and the locking pin is engaged with a concave part formed in matching with the outer diameter of the locking pin by bending the tip part of the shift arm in order to ensure the rigidity of the shift arm.

However, as disclosed in the above-mentioned Japanese Patent Laid-Open No. 2011-196433, in the structure in which the locking pin is engaged with the concave part formed in the shift arm, there is a possibility that friction increases are attributed to the pressing of the shift arm by the locking pin in the axial direction. For smoother gear shifting, a structure in which the shift arm is engaged with the locking pin with a surface with less friction is preferable. However, there is a concern that the rigidity of the shift arm lowers if merely an engagement hole for engagement with the locking pin is formed in the shift arm having the arc-shaped insertion hole in which the interlocking shaft to be interlocked and connected the shift position sensor is inserted.

SUMMARY AND OBJECTS OF THE INVENTION

According to an embodiment of the present invention, is made in view of such circumstances and an object thereof is to provide a power unit for a saddle-type vehicle in which the friction surface between a shift arm and a locking pin is reduced with suppression of the lowering of the rigidity of the shift arm to enable smooth gear shifting.

According to an embodiment of the present invention, the following configuration in a power unit for a saddle-type vehicle in which gear trains of a plurality of shift stages one of which is selectively established according to rotation of a shift drum are provided in a power train system between a drive source that exerts a driving force and a drive wheel. A change mechanism for rotating the shift drum includes a shift spindle that rotates according to input of a gear shifting operating force and a shift arm that engages with a locking pin provided on the side of the shift drum and is fixed to the shift spindle. A detection shaft of a shift position sensor for detecting the rotational position of the shift drum is interlocked and connected with the shift drum. More specifically, an interlocking shaft for interlocking and connecting the detection shaft of the shift position sensor is connected to the shift drum in such a manner so as to be coaxial with a rotational axis line of the shift drum and be incapable of rotation relative to the shift drum. Furthermore, in the shift arm, an engagement hole having an elongate hole shape extends along one diameter line of the shift spindle in such a manner as to allow insertion and engagement of the locking pin. An insertion hole extends into an arc shape centered at a center axis line of the shift spindle in such a manner so as to allow insertion of the interlocking shaft. In addition, at least a part penetrating through the insertion hole in the interlocking shaft is formed with a diameter smaller than the diameter of the locking pin and the width of the insertion hole is set smaller than the width of the engagement hole.

According to an embodiment of the present invention, the engagement hole is formed so as to continue to a longitudinally center part of the insertion hole and extend to the opposite side to the shift spindle.

According to an embodiment of the present invention, the interlocking shaft is formed so that a part on the side of the shift drum is larger in diameter than the part inserted in the insertion hole.

According to an embodiment of the present invention, a pawl ratchet mechanism having a cup-shaped rotating component that rotates together with the shift drum and a shifter assembly that has the locking pin and is rotatably housed in the rotating component is provided between the shift arm and the shift drum in such a manner so as to convert one round of reciprocal rotation of the shift spindle and the shift arm to rotation of the shift drum by a predetermined angle. Furthermore, the interlocking shaft penetrating the shifter assembly in such a manner so as to rotatably support the shifter assembly is press-fitted into the rotating component fixed to the shift drum.

According to an embodiment of the present invention, a pawl ratchet mechanism having a cup-shaped rotating component that rotates together with the shift drum and a shifter assembly that has the locking pin and is rotatably housed in the rotating component is provided between the shift arm and the shift drum in such a manner so as to convert one round of reciprocal rotation of the shift spindle and the shift arm to rotation of the shift drum by a predetermined angle. Furthermore, the interlocking shaft is coaxially press-fitted to a bolt that penetrates the shifter assembly in such a manner so as to rotatably support the shifter assembly and fastens the rotating component to the shift drum.

According to an embodiment of the present invention, an engagement groove extending into a straight line shape in such a manner wherein both ends are opened at the outer circumference of the interlocking shaft is formed at an axial end of the interlocking shaft on the side of the shift position sensor. An engagement pin fitted into the engagement groove is provided on a joint component connected to the detection shaft in such a manner so as to be incapable of rotation relative to the detection shaft.

According to an embodiment of the present invention, the joint component is formed into a stepped cylindrical shape having a smaller-diameter tubular part into which the interlocking shaft is fitted and a larger-diameter tubular part coaxially continuing to the smaller-diameter tubular part in such a manner so as to allow insertion of the detection shaft.

According to an embodiment of the present invention, a second engagement pin fitted into an engagement recess that is formed at an end part of the joint component on the side of the shift position sensor and is located on one diameter line of the joint component is provided on the detection shaft perpendicularly to a center axis line of the detection shaft.

According to an embodiment of the present invention, the shift arm includes the engagement hole and the insertion hole. The engagement hole has an elongate hole shape extending along one diameter line of the shift spindle in such a manner so as to allow insertion and engagement of the locking pin. The insertion hole extends into an arc shape and allows insertion of the interlocking shaft connected to the shift drum in such a manner so as to interlock and connect the detection shaft of the shift position sensor and is incapable of rotation relative to the shift drum. Furthermore, at least the part penetrating through the insertion hole in the interlocking shaft is smaller in diameter than the locking pin and the width of the insertion hole is smaller than that of the engagement hole. Therefore, the opening area of the insertion hole made in the shift arm can be set comparatively small. Moreover, because the locking pin is engaged with the engagement hole, the shift arm is not pressed by the locking pin in the axial direction and the friction surface between the shift arm and the locking pin can be reduced. As a result, smooth gear shifting is enabled with suppression of the lowering of the rigidity of the shift arm.

According to an embodiment of the present invention, the engagement hole continuing to the longitudinally center part of the insertion hole extends to the opposite side to the shift spindle. Thus, the engagement hole and the insertion hole can be formed symmetrically with respect to a straight line passing through the rotational axis line of the shift arm. Accordingly, the engagement hole and the insertion hole are made without imbalance in the opening part in the shift arm and the rigidity of the shift arm can be ensured.

According to an embodiment of the present invention, the part on the shift position sensor side in the interlocking shaft is formed with a smaller diameter in view of the fact that it is not required to have high rigidity. Therefore, the width of the insertion hole can be set small, and the connecting force of the interlocking shaft with the shift drum can be enhanced by forming the interlocking shaft with the larger diameter on the shift drum side, wherein a high rigidity is necessary.

According to an embodiment of the present invention, the interlocking shaft penetrating the shifter assembly that serves as part of the pawl ratchet mechanism and has the locking pin in such a manner so as to rotatably support this shifter assembly is press-fitted into the rotating component fixed to the shift drum as part of the pawl ratchet mechanism. Therefore, a dedicated component for connecting the interlocking shaft to the shift drum is unnecessary and the number of components can be reduced.

According to an embodiment of the present invention, the interlocking shaft is coaxially press-fitted to the bolt penetrating the shifter assembly that serves as part of the pawl ratchet mechanism and has the locking pin in such a manner so as to rotatably support this shifter assembly. This allows free setting of the relative positions of the shift position sensor and the bolt. Thus, application to a plurality of models and a plurality of kinds of shift position sensors is permitted, which can enhance the versatility.

According to an embodiment of the present invention, the engagement pin provided on the joint component connected to the detection shaft in such a manner so as to be incapable of rotation relative to the detection shaft is fitted into the engagement groove formed at the axial end of the interlocking shaft on the shift position sensor side. This facilitates the work of interlocking and connecting the interlocking shaft and the detection shaft. Thus, the assemblability is enhanced.

According to an embodiment of the present invention, the joint component is formed into a stepped cylindrical shape with a larger diameter on the detection shaft side. This makes it easy to rotate the joint component and align it with the shift position sensor with the joint component assembled to the interlocking shaft at the time of the work of connecting the interlocking shaft and the shift position sensor. Thus, the work of assembling the shift position sensor becomes easy.

According to an embodiment of the present invention, the second engagement pin provided on the detection shaft is fitted into the engagement recess formed at the end part of the joint component on the shift position sensor side. Therefore, it is easy to rotate and align the detection shaft by the second engagement pin at the time of the work of connecting the interlocking shaft and the shift position sensor. Thus, the work of assembling the shift position sensor becomes easy.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first embodiment of the present invention will be described with reference toFIGS. 1 to 6. Referring first toFIG. 1, a vehicle body frame F of a motorcycle as a saddle-type vehicle includes the following components a head pipe12that steerably supports a front fork11rotatably supporting a front wheel WF at its lower end part, a main frame13extending rearwardly from this head pipe12, a pair of left and right center frames14extending downwardly from the rear end of this main frame13, a pair of left and right down frames15extending rearwardly and downwardly from the head pipe12with a steeper inclination angle compared with the main frame13, a pair of left and right pivot plates16provided at the lower end parts of the center frames14and a pair of left and right rear frames17extending rearwardly from the upper parts of the center frames14and the pivot plates16.

A steering handlebar18is connected to the upper end of the front fork11and a riding seat19is provided above the rear frames17. A fuel tank20straddling the main frame13in front of the riding seat19is attached to the main frame13.

At the part surrounded by the main frame13, the center frames14and the down frames15, a power unit P is disposed so as to be supported by the down frames15and the pivot plates16.

On the pivot plates16, the front end parts of swing arms21that rotatably support, at their rear end parts, a rear wheel WR as a drive wheel driven by the power unit P are slidably supported with the intermediary of a support shaft22. A rear shock absorber unit23is provided between the rear frames17and the swing arms21.

Referring toFIG. 2, the power unit P is composed of an engine E as a drive source and a transmission M provided in a power train system between this engine E and the rear wheel WR.

An engine main body24of the engine E includes a crankcase25, a cylinder block26, a cylinder head27and a head cover28and is formed as an inline-four engine. An oil pan29(seeFIG. 1) is joined to the lower part of the crankcase25. In the crankcase25, a crankshaft30having a rotational axis line extending along the vehicle width direction is rotatably supported.

Pistons31slidably fitted into the cylinder block26on each cylinder basis are connected to the crankshaft30in common with combustion chambers32formed at the tops of the respective pistons31are formed between the cylinder block26and the cylinder head27on each cylinder basis.

An electric generator34is joined to one end of the crankshaft30. This electric generator34is housed in an electric generator room36formed between an electric generator cover35connected to the crankcase25and the crankcase25. The rotational power of the crankshaft30is transmitted to the rear wheel WR of the motorcycle via an endless chain37. More specifically, the rotational power of the crankshaft30is transmitted to the chain37via a primary reduction gear38, a damper spring39, a start clutch40and the transmission M.

The transmission M includes a main shaft41, a countershaft42and gear trains of a plurality of shift stages, specifically e.g. first to sixth gear trains G1, G2, G3, G4, G5, and G6. To the main shaft41, the rotational power of the crankshaft30is input via the damper spring39and the start clutch40. The countershaft42has an axis line parallel to the main shaft41. In addition, a drive sprocket43around which the chain37is wound is fixed at a protrusion part from the crankcase25. The first to sixth gear trains G1to G6allow selective establishment of the shift stage and are provided between the main shaft41and the countershaft42. The first to sixth gear trains G1to G6are each so formed that a drive gear and a driven gear making a pair mesh with each other.

Referring also toFIG. 3, below the drive sprocket43, a shift spindle45is rotatably supported on the lower part of the left sidewall of the crankcase25and a cover component44that covers the lower part of the left sidewall of the crankcase25and is connected to this crankcase25. To this shift spindle45, a change pedal46rotatably supported by the left pivot plate16is connected via a link47. A gear shifting operating force from the change pedal46is input to the shift spindle45.

Referring also toFIG. 4, the transmission M has a shift drum48A and shift forks52,53, and54in addition to the main shaft41, the countershaft42and the first to sixth gear trains G1to G6. The shift drum48A can rotate about an axis line parallel to the main shaft41and the countershaft42in order to selectively establish one of the first to sixth gear trains G1to G6and is rotatably supported by the crankcase25. The shift forks52,53, and54engage with guide grooves49,50, and51made in the outer circumference of the shift drum48A and are supported by a shift fork shaft55movably in the axial direction. The shift fork shaft55has an axis line parallel to the shift drum48A and is supported by the crankcase25.

The shift spindle45serves as part of a change mechanism56that rotates the shift drum48A according to input of a gear shifting operating force. Most parts of this change mechanism56is housed in a change mechanism room57formed between the left sidewall of the crankcase25and the cover component44.

Referring also toFIG. 5, the change mechanism56has a shift arm62and a pawl ratchet mechanism63A. The shift arm62engages with a locking pin61provided on the side of the shift drum48A and is fixed to the shift spindle45. The pawl ratchet mechanism63A is provided between the shift arm62and the shift drum in such a manner so as to convert one round of reciprocal rotation of the shift spindle45and the shift arm62to rotation of the shift drum48A by a predetermined angle.

Referring also toFIG. 6, at the base part of the shift arm62on the side of the shift spindle45, an elongate hole64that is long in the direction perpendicular to a first straight line L1passing through the center axis line of the shift spindle45is made and a protrusion65located on the first straight line L1is made in the shift arm62in such a manner so as to sandwich the elongate hole64between it and the shift spindle45.

Meanwhile, one end part of a pin66inserted in the elongate hole64is fixed on the left sidewall of the crankcase25, and a clamp spring67having, at its both ends, a pair of clamp arms67athat sandwich the protrusion65and the pin66from both sides is disposed between the shift arm62and the crankcase25in such a manner so as to surround the shift spindle45. This makes the shift arm62to be biased toward a reference position at which the protrusion65and the pin66are arranged on the first straight line L1.

The pawl ratchet mechanism63A is a known one having a cup-shaped rotating component68A that rotates together with the shift drum48A and a shifter assembly69that has the locking pin61at a position offset from the rotational axis line of the shift drum48A and is rotatably housed in the rotating component68A.

The rotating component68A is press-fitted to one end part of the shift drum48A and a ball bearing70is provided between this rotating component68A and the crankcase25. Furthermore, in the change mechanism room57, a ring component72having notches71individually corresponding to the first to sixth positions at its outer circumference is fixed to the rotating component68A and a drum stopper arm73is selectively engaged with these notches71.

This drum stopper arm is composed of an arm74and a roller75. The base end part of the arm74is rotatably journaled by a support shaft76that has an axis line parallel to the shift spindle45and is provided on the crankcase25. The roller75is journaled by the tip of the arm74in such a manner so as to engage with one of the respective notches71. A twisted spring77is provided between the base end part of the arm74and the crankcase25. To engage the roller75with one of the respective notches71, the arm74is biased toward the rotation center of the ring component72, i.e. the center axis line of the shift drum48A, by a spring force exerted by the twisted spring77.

The rotational position of the shift drum48A is detected by a shift position sensor80attached to the cover component44. This shift position sensor80has a detection shaft81coaxial with the shift drum48A and an interlocking shaft82for interlocking and connecting the detection shaft81is connected to the shift drum48A in such a manner so as to be coaxial with the rotational axis line of the shift drum48A and be incapable of rotation relative to it.

The interlocking shaft82is press-fitted into the rotating component68A fixed to the shift drum48A and penetrates the shifter assembly69in such a manner so as to rotatably support this shifter assembly69.

Meanwhile, an engagement hole83and an insertion hole84are made in the shift arm62. The engagement hole83has an elongated hole shape extending along one diameter line of the shift spindle45in such a manner so as to allow insertion and engagement of the locking pin61. The insertion hole84extends into an arc shape centered at the center axis line of the shift spindle45in such a manner so as to allow insertion of the interlocking shaft82. At least the part penetrating through the insertion hole84in the interlocking shaft82is formed with a diameter smaller than that of the locking pin61.

In this embodiment, the interlocking shaft82is formed so as to monolithically have a larger-diameter part82aand a smaller-diameter part82bwhose diameter is smaller than that of this larger-diameter part82ain that order from the side of the shift drum48A. The larger-diameter part82ais press-fitted into the rotating component68A and penetrates this rotating component68A and the shifter assembly69, and the smaller-diameter part82bis inserted in the insertion hole84of the shift arm62.

In addition, because the interlocking shaft82is smaller in diameter than the locking pin61at the part inserted in the insertion hole84, width d1of the insertion hole84is set smaller than width d2of the engagement hole83.

Furthermore, the engagement hole83extends long along a second straight line L2that passes through the center axis line of the shift spindle45and extends along a direction forming an angle α with the first straight line L1, and is formed so as to continue to the longitudinally center part of the insertion hole84and extend to the opposite side to the shift spindle45.

At the axial end of the interlocking shaft82on the side of the shift position sensor80, i.e. the axial end of the smaller-diameter part82bon the side of the shift position sensor80, an engagement groove86is formed that is located on one diameter line of the smaller-diameter part82band has both ends opened at the outer circumference of this smaller-diameter part82b. A first engagement pin88fitted into the engagement groove86is provided on a joint component87connected to the detection shaft81in such a manner so as to be incapable of rotation relative to it.

In addition, the joint component87is formed into a stepped cylindrical shape having a smaller-diameter tubular part87ainto which the smaller-diameter part82bof the interlocking shaft82is fitted and a larger-diameter tubular part87bcoaxially continuing to the smaller-diameter tubular part87ain such a manner so as to allow insertion of the detection shaft81. A second engagement pin90, fitted into an engagement recess89that is formed at the end part of the joint component87on the side of the shift position sensor80and is located on one diameter line of this joint component87, is provided on the detection shaft81perpendicularly to the center axis line thereof.

Next, the effects of this embodiment will be described. The interlocking shaft82for interlocking and connecting the detection shaft81of the shift position sensor80is connected to the shift drum48A in such a manner so as to be coaxial with the rotational axis line of the shift drum48A and be incapable of rotation relative to it. Furthermore, in the shift arm62, the engagement hole83having an elongate hole shape extending along one diameter line of the shift spindle in such a manner so as to allow insertion and engagement of the locking pin61and the insertion hole84extending into an arc shape centered at the center axis line of the shift spindle45in such a manner as to allow insertion of the interlocking shaft82are formed. In addition, at least the part penetrating through the insertion hole84in the interlocking shaft82is formed with a diameter smaller than that of the locking pin61and the width d1of the insertion hole84is set smaller than the width d2of the engagement hole83. Therefore, the opening area of the insertion hole84made in the shift arm62can be set comparatively small. Moreover, because the locking pin61is engaged with the engagement hole83, the shift arm62is not pressed by the locking pin61in the axial direction and the friction surface between the shift arm62and the locking pin61can be reduced. As a result, smooth gear shifting is enabled with suppression of the lowering of the rigidity of the shift arm62.

Furthermore, the engagement hole83is formed so as to continue to the longitudinally center part of the insertion hole84and extend to the opposite side to the shift spindle45. Thus, the engagement hole83and the insertion hole84can be formed symmetrically with respect to the second straight line L2passing through the rotational axis line of the shift arm62and the widthwise center of the engagement hole83. Accordingly, the engagement hole83and the insertion hole84are made without imbalance in the opening part in the shift arm62. Thus, the rigidity of the shift arm62can be ensured.

In addition, the interlocking shaft82is formed so that the part on the side of the shift drum48A is larger in diameter than the part inserted in the insertion hole84, and the part on the side of the shift position sensor80in the interlocking shaft82is formed with a smaller diameter due to the fact that it is not required to have high rigidity. Therefore, the width of the insertion hole84can be set small, and the connecting force of the interlocking shaft82with the shift drum48A can be enhanced by forming the interlocking shaft82with the larger diameter on the side of the shift drum48A, on which a high rigidity is necessary.

Moreover, the interlocking shaft82penetrating the shifter assembly69serving as part of the pawl ratchet mechanism63A in such a manner so as to rotatably support this shifter assembly69is press-fitted into the rotating component68A fixed to the shift drum48A. Therefore, a dedicated component for connecting the interlocking shaft82to the shift drum48A is unnecessary. Thus, the number of components can be reduced.

Furthermore, the engagement groove86that is located on one diameter line of the interlocking shaft82and has both ends opened at the outer circumference of this interlocking shaft82is formed at the axial end of the interlocking shaft82on the side of the shift position sensor80, and the first engagement pin88fitted into the engagement groove86is provided on the joint component87connected to the detection shaft81in such a manner so as to be incapable of rotation relative to it. This facilitates the work of interlocking and connecting the interlocking shaft82and the detection shaft81for enhancing the assemblability.

In addition, the joint component87is formed into a stepped cylindrical shape having the smaller-diameter tubular part87ainto which the interlocking shaft82is fitted and the larger-diameter tubular part87bcoaxially continuing to the smaller-diameter tubular part87ain such a manner as to allow insertion of the detection shaft81. This makes it easy to rotate the joint component87and align it with the shift position sensor80with the joint component87assembled to the interlocking shaft82at the time of the work of connecting the interlocking shaft82and the shift position sensor80. Thus, the work of assembling the shift position sensor80becomes easy.

Moreover, the second engagement pin90fitted into the engagement recess89that is formed at the end part of the joint component87on the side of the shift position sensor80and is located on one diameter line of this joint component87is provided on the detection shaft81perpendicularly to the center axis line thereof. Therefore, it is easy to rotate and align the detection shaft81by the second engagement pin90at the time of the work of connecting the interlocking shaft82and the shift position sensor80. Thus, the work of assembling the shift position sensor80becomes easy.

FIG. 7shows a second embodiment of the present invention. The part corresponding to the first embodiment is only shown in the diagram with the same reference numeral. A detailed description thereof is omitted.

A pawl ratchet mechanism63B provided between a shift arm62and a shift drum48B in such a manner so as to convert one round of reciprocal rotation of the shift arm62to rotation of the shift drum48B by a predetermined angle has a cup-shaped rotating component68B coaxially fixed to the shift drum48B by a bolt91and a shifter assembly69that has a locking pin61and is rotatably housed in the rotating component68B. Notches71with which a roller75of a stopper arm73is engaged are formed at the outer circumference of the rotating component68B.

The rotational position of the shift drum48B is detected by a shift position sensor80attached to the cover component44. A detection shaft81that is possessed by this shift position sensor80and is coaxial with the shift drum48B is interlocked and connected, via a joint component93, with an interlocking shaft92connected to the shift drum48B in such a manner so as to be coaxial with the rotational axis line of the shift drum48B and is incapable of rotation relative to it.

The bolt91monolithically has an extending shaft part91athat coaxially penetrates the shifter assembly69and rotatably supports this shifter assembly69and a press-fitting shaft part91bcontinuing to this extending shaft part91a. The press-fitting shaft part91bhas a non-circular cross-sectional shape and protrudes from the shifter assembly69. The interlocking shaft92formed with a smaller diameter compared with the locking pin61is press-fitted to the press-fitting shaft part91b.

The joint component93is formed into a cylindrical shape in such a manner that the other end part of the interlocking shaft92and the detection shaft81of the shift position sensor80are fitted into both end parts of the joint component93. At the axial end of the interlocking shaft92on the side of the shift position sensor80, an engagement groove94is formed that extends into a straight line shape at a position offset from the center line of the axis of rotation of the interlocking shaft92and has both ends opened at the outer circumference of this interlocking shaft92. A first engagement pin95fitted into the engagement groove94is provided on the joint component93.

Furthermore, a second engagement pin97fitted into an engagement recess96that is formed at the end part of the joint component93on the side of the shift position sensor80and is located on one diameter line of the joint component93is provided on the detection shaft81perpendicularly to the center axis line thereof.

According to this second embodiment, the interlocking shaft92is coaxially press-fitted to the bolt91penetrating the shifter assembly69in such a manner so as to rotatably support the shifter assembly69, which serves as part of the pawl ratchet mechanism63B and has the locking pin61. This allows free setting of the relative positions of the shift position sensor80and the bolt91. Thus, application to a plurality of models and a plurality of kinds of shift position sensors80is permitted. Thus, the versatility is enhanced.

Furthermore, the first engagement pin95provided on the joint component93is fitted into the engagement groove94extending into a straight line shape at a position offset from the center axis line of the interlocking shaft92. This uniquely settles the circumferential relative positions of the joint component93and the interlocking shaft92.

As a third embodiment of the present invention, as shown inFIG. 8, the interlocking shaft82penetrating the shifter assembly69in such a manner so as to rotatably support the shifter assembly69serving as part of the pawl ratchet mechanism63A may be connected to the detection shaft81of the shift position sensor80via the joint component93.