JP2018091375A - Drum type shift operation mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drum type shift operation mechanism with waiting actuation capable of attaining downsizing in an axial direction and reduction of a shift operation force.SOLUTION: A fork guide mechanism of a drum member guides a shift fork in such a manner that a shifter member is located at a reference position where the shifter member is not engaged with both first and second shift members in a concave and convex shape when the drum member is located at a neutral position, that the shifter member is made movable between a first shift position where the shifter member is engaged with the first shift member in the concave and convex shape, and the reference position when the drum member is located at the first shift position, and that the shifter member is made movable between a second shift position where the shifter member is engaged with the second shift member in the concave and convex shape, and the reference position when the drum member is located at a second operation position. A slider guide groove of the drum member guides a slider member that is supported in a movable manner by a boss part of the shift form, such that the movement of the shifter member between the reference position and the first shift position is prevented from being disturbed when the drum member is located at the first shift position.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a drum-type speed change operation mechanism.

  A drum-type transmission has been proposed as a transmission used for a traveling transmission path in a working vehicle such as a utility vehicle or a tractor.

  The drum-type transmission is supported by first and second transmission gears rotatably supported on a first transmission rotation shaft, and non-rotatably supported by a second transmission rotation shaft, and the first and second transmission gears. First and second transmission gears that directly or indirectly mesh with each other, and a transmission operation mechanism that selectively disables the first and second transmission gears from rotating relative to the first transmission rotation shaft, The shift operation mechanism selectively selects a first gear train formed by the first transmission gear and the first transmission gear, and a second gear train formed by the second transmission gear and the second transmission gear. When the transmission state is established, the rotational power transmitted between the first and second transmission rotation shafts is shifted.

  The shift operation mechanism includes a shifter member supported between the first transmission gear and the second transmission gear so as not to rotate relative to the first transmission rotation shaft and to be movable in the axial direction, and a fork parallel to the first transmission rotation shaft. A fork guide in which a shaft, a shift fork that is supported by the fork shaft so as to be movable in the axial direction, and moves the shifter member in the axial direction in accordance with the axial movement of the shaft, and an engagement pin portion of the shift fork The shift fork guided by the fork guide groove in the axial direction according to the rotation of the drum member, and thereby the shifter member. Is selectively engaged with the first and second transmission gears.

  Specifically, the shifter member and the transmission gear are provided with uneven portions on opposite end surfaces thereof, and the shifter member is moved toward the side closer to the transmission member in the axial direction, whereby the shifter member The concavo-convex portions engage with the concavo-convex portions of the corresponding speed change member, and both rotate integrally.

By the way, when the shift fork and the shifter member are moved in the axial direction by the rotation operation of the drum member, and the shifter member is engaged with the shift member, the protrusions of the uneven portions and the protrusions of the shifter member When the projections of the concavo-convex portions of the speed change member are in contact with each other, there may occur a situation where the concavo-convex engagement of the shifter member and the speed change member is not completed immediately (the butt-contact state between the convex portions).
When such a projecting state of the protrusions occurs, the drum member cannot be rotated to the target operation position until the uneven engagement of the shifter member and the speed change member is completed. You will have to continue to apply operational power.

  In view of this point, a drum-type speed change operation mechanism having a standby action has been proposed (see Patent Document 1 below).

  The conventional drum-type speed change operation mechanism with standby action described in Patent Document 1 includes a shifter member, a fork shaft, a shift fork, and a drum member, and the fork shaft is movable in the axial direction. A shaft guide groove is provided in addition to the fork guide groove, and a spring receiving member whose relative movement toward the side away from the shift fork is restricted in the axial direction by a locking member fixed to the fork shaft is provided on the fork shaft. And a lost motion spring (standby spring) is inserted between the spring receiving member and the shift fork, and the fork shaft is moved in the axial direction via the shaft guide groove according to the rotation of the drum member. The lost motion spring via the locking member and the spring receiving member by the axial movement of the fork shaft By compression, and is configured to exert a spring load caused by the compression of the lost motion spring to the shift fork.

  In the conventional drum-type speed change operation mechanism with standby action, the drum member can be rotated in advance to the target speed change position even when the projecting portions are brought into contact with each other. Is moved in the axial direction so that the lost motion spring is in a compressed state having retained elasticity.

  The retained elasticity of the lost motion spring is such that when the shift fork continues to press the shift fork in the direction in which the shift member is pressed toward the speed change member and the butted state of the protrusions is eliminated, the shifter member and the The uneven engagement of the speed change member is completed.

As described above, the conventional drum-type speed change operation mechanism with a standby function can cause the drum member to perform a pre-rotation operation to a predetermined speed change position even when the projecting portions are brought into contact with each other. It is useful in that the shifting operation can be completed by the retained elasticity of the lost motion spring at the time when the butted state of the convex portions is canceled, in order to obtain such a standby action, the shift fork, The whole of the fork shaft supporting the locking member and the spring receiving member must be moved in the axial direction.
For this reason, there is a problem that a space for securing the axial movement range of the fork shaft is required and a large operating force is required to move the entire fork shaft.

Japanese Patent No. 5750485

  The present invention has been made in view of the above-described prior art, and is a drum-type speed change operation mechanism with a standby function, which is capable of downsizing in the axial direction and reducing the operation force when shifting the drum member. An object of the present invention is to provide a type shift operation mechanism.

  In order to achieve the above object, the first aspect of the present invention is supported between the first and second speed change members so as not to rotate relative to the transmission rotating shaft and to be movable in the axial direction. And a first shifter member that engages with the first and second speed change members according to the movement to the second side on the other side, and a drum that has a first fork guide groove and is rotated about an axis. A member, a fork shaft disposed in parallel with the transmission rotation shaft, a first boss portion supported by the fork shaft so as to be movable in an axial direction, and a first engagement engaged with the first fork guide groove A drum-type speed change operation mechanism including a pin portion and a first shift fork having a first fork portion that engages with the first shifter member, and biases the first boss portion toward the first side in the axial direction. A first shift fork pushing spring and the first boss portion; An axial end position is supported by a slider guide groove provided in the drum member, supported by the first boss portion so as to be movable in the axial direction in a state where a moving end toward the second axial direction is defined by the provided stop portion. A regulated slider member; and a slider member pushing spring that biases the slider member toward the second axial direction with a biasing force larger than that of the first shift fork pushing spring, and the first shift fork and the first shift fork The first shifter member is a reference position where the first shifter member is not engaged with any of the first and second transmission members, and the first shifter member is the first and second transmission members. The first and second shift positions that engage with each other can be selectively taken, and the first fork guide groove has the drum member positioned at a neutral position around the axis. The first shift fork is fixed at the reference position, and when the drum member is positioned at the first operation position on one side around the axis from the neutral position, the first shift fork is set at the reference position and the first shift position. The first shift fork moves between the reference position and the second shift position when the drum member is positioned at the second operation position on the other side around the axis from the neutral position. The slider guide groove obstructs the movement of the first shift fork between the reference position and the first shift position when the drum member is positioned at the first shift position. The slider member is guided so as not to move, and when the drum member is positioned at the second speed change position, the slider member biased by the slider member pushing spring moves the first shift fork to a reference position. There is provided a drum-type speed change operation mechanism having a groove shape that allows the slider member to move in the axial direction so that the slider member can be pushed to the second speed change position.

  In the first mode, the axial position where the slider member is in contact with the stop when the first shift fork is positioned at the reference position, the first shift position, and the second shift position. When the reference position, the first displacement position, and the second displacement position are set, the slider guide groove fixes the slider member to the reference position when the drum member is positioned at the neutral position, and the drum member Is positioned at the first operation position, the slider member is fixed at the first displacement position, and when the drum member is positioned at the second operation position, the slider member is at the reference position and the second displacement position. Configured to have a groove shape that allows movement between the two.

  In the second form, the slider guide groove is urged toward the second axial direction by the slider member pushing spring when the drum member is located at a position other than the first speed change position. However, it has a groove shape that allows the first shift fork to move in the axial direction while following the movement in the axial direction while remaining in contact with the stop portion.

  In the various configurations of the first aspect, the drum-type speed change operation mechanism according to the present invention is further a second shifter member supported on the transmission rotation shaft so as not to be relatively rotatable and axially movable. A second shifter member that can engage with the third speed change member by being moved in the axial direction toward the third speed change member that is rotatably supported by the rotation shaft, and can move in the axial direction on the fork shaft. A second boss portion supported by the second boss portion, a second engagement pin portion engaged with a second fork guide groove provided in the drum member, and a second fork portion engaged with the second shifter member. A shift fork and a second shift fork pushing spring that urges the second boss portion in a direction in which the second shifter member is pressed toward the third speed change member may be provided.

  The second shift fork and the second shifter member are axial positions, the second shifter member is not engaged with the third transmission member, and the second shifter member is uneven with the third transmission member. The first fork guide groove is positioned at a third operation position where the drum member is displaced in a neutral position, and the first and second operation positions are displaced about the axis. The second fork guide groove has a groove shape for fixing the first shift fork at a reference position when the drum member is positioned at the third operation position. Is allowed to move between a reference position and a third shift position, and when the drum member is positioned at an operation position other than the third operation position, a groove shape that fixes the second shift fork at the reference position It is assumed to have.

  For example, the drum member is positioned at the third operation position when rotated by a predetermined angle around the axis from the first operation position to one side.

  The drum-type speed change operation mechanism including the second shifter member preferably includes a main body portion that is externally inserted in the drum member so as to be relatively rotatable, and a cam push portion that extends radially outward from the main body portion. A parking coil spring inserted into the drum member in a state where one end side is operatively connected to the parking push member and the other end side is operatively connected to the drum member. When the circumferential load applied to the moving part is less than a predetermined value, the parking member is connected so as not to rotate relative to each other so that the parking push member integrally rotates about the axis as the drum member rotates about the axis. On the other hand, when the circumferential load applied to the cam pushing portion exceeds a predetermined value, the drum member is elastically deformed so that the drum member is rotated relative to the parking pushing member around the axis. A parking coil spring that is permitted to swing, and a parking operation arm that is swingable about a swing axis parallel to the transmission rotation shaft and has an engagement portion on a free end side, wherein the swing axis A parking position is established in which the engaging portion engages with a concavo-convex portion that is provided on the second shifter member so as to face radially outward to forcibly stop the second shifter member from rotating. And a parking release spring that urges the parking operation arm about the swing axis in a direction in which the engagement portion is separated from the concavo-convex portion. The parking arm is arranged to swing to the parking position around the swing axis in response to the rotation of the drum member to the parking position. When the cam pushing portion swings the parking operation arm toward the parking position in accordance with the rolling operation, the engagement portion of the parking operation arm hits the convex portion of the concavo-convex portion of the second shifter member. When a circumferential load exceeding the predetermined value is applied to the cam pushing portion, the drum member is rotated relative to the parking pushing member up to the parking operation position while elastically deforming the parking coil spring. When the second shifter member rotates about the axis and the engaging portion and the concavo-convex portion are aligned, the parking coil spring resists the biasing force of the parking release spring by the retained elasticity accompanying elastic deformation. The parking operation arm is swung to a parking position to complete the engagement of the engaging portion and the concavo-convex portion.

  According to a second aspect of the present invention, in order to achieve the above object, the first and second transmission members of the first to fourth transmission members, which are rotatable relative to the transmission rotation shaft and arranged in series, are provided. In the meantime, the first and second speed change members are respectively supported by the transmission rotation shaft so as not to be relatively rotatable and movable in the axial direction, and according to the movement to the first side on the one side in the axial direction and the second side on the other side. Between the first shifter member that engages with the concave and convex portions and the third and fourth speed change members, the transmission rotation shaft is supported so as not to rotate relative to the transmission rotation shaft and to be movable in the axial direction. A second shifter member that engages with the third and fourth speed change members according to the movement to the side, and a drum member that has first and second fork guide grooves and is rotated about an axis, Fork shaft disposed parallel to the transmission rotation shaft A first boss portion supported on the fork shaft so as to be movable in the axial direction, a first engagement pin portion engaged with the first fork guide groove, and a first fork portion engaged with the first shifter member. A first shift fork having a second boss portion supported on the fork shaft so as to be movable in the axial direction, a second engagement pin portion engaged with the second fork guide groove, and the second shifter member. A second shift fork having a second fork portion for rotating the drum member around the axis, and the first and second shift forks are guided in the first and second fork guide grooves to move in the axial direction. In response to this, the first and second shifter members are drum-type speed change operation mechanisms that selectively engage with the corresponding speed change members, and attach the first boss portion to the second side in the axial direction. 1st shift A fork pushing spring, a second shift fork pushing spring for urging the second boss portion toward the first axial direction, and a first stop provided on the first boss portion toward the first axial direction. A first slider member that is supported by the first boss portion so as to be movable in the axial direction in a state in which the moving end of the first boss portion is defined, and whose axial position is guided by a first slider groove provided in the drum member; The second stop portion provided on the two boss portions is supported by the second boss portion so as to be movable in the axial direction in a state where the moving end toward the second axial direction is defined by the second stop portion, and is provided on the drum member. A second slider member whose axial position is guided by the slider groove, and a first slider member pushing that pushes the first slider member toward the first axial direction with a larger urging force than the first shift fork pushing spring. Spring and front A drum-type speed change operation mechanism is provided that includes a second slider member pushing spring that pushes the second slider member toward the second axial direction with a larger biasing force than the second shift fork pushing spring.

  The first shifter member and the first shift fork are related to an axial position, the reference position where the first shifter member is not engaged with any of the first and second speed change members, and the first shifter member is the first. And the first shift position and the second shift position for engaging with the second speed change member, respectively, and the second shifter member and the second shift fork are arranged with respect to the axial position. A reference position where the shifter member does not engage with the third and fourth speed change members and a third and fourth speed change position where the second shifter member engages with the third and fourth speed change members respectively is selected. It can be taken.

  The first fork guide groove fixes the first shift fork to a reference position when the drum member is positioned at the neutral position around the axis, and the first fork guide groove is located at one side around the axis from the neutral position. The first shift fork is allowed to move between the reference position and the first shift position, and the drum member is positioned at the third operation position on one side around the axis from the first operation position. The first shift fork is fixed at the reference position, and when the drum member is positioned at the second operation position on the other side of the axis from the neutral position, the first shift fork is at the reference position and the second shift position. A groove shape for fixing the first shift fork at a reference position when the drum member is positioned at the fourth operation position on the other side around the axis from the second operation position. The first slice The guide groove is configured such that when the drum member is positioned at the first speed change position, the first shift fork is guided to the first fork guide while the first slider member is in contact with the first stop portion. A range in which the first slider member can move in the axial direction is defined so that movement between the reference position guided by the groove and the first shift position can be performed, and when the drum member is positioned at the second shift position, The first shift fork has a groove shape for guiding the first slider member so as not to disturb the movement between the reference position and the second shift position.

  The second fork guide groove fixes the second shift fork to a reference position when the drum member is positioned at the first operation position, the neutral position, and the second operation position, and the drum member operates at the third operation position. The second shift fork is allowed to move between the reference position and the third speed change position when positioned at the position, and the second shift fork is positioned when the drum member is positioned at the fourth operation position. The second slider guide groove has a groove shape that allows movement between a reference position and a fourth speed change position, and the second slider guide groove has the second shift when the drum member is positioned at the third speed change position. The second slider member is guided so as not to interfere with the movement of the fork between the reference position and the third shift position, and when the drum member is positioned at the fourth shift position, the second slider member is Contact the second stop A groove shape that defines a movable range in the axial direction of the second slider member so that the second shift fork can move between the reference position guided by the second fork guide groove and the fourth shift position in a state of being moved. It is supposed to have.

  Preferably, each of the first and second slider member pushing springs is a single spring having one end engaged with the first slider member and the other end engaged with the second slider member.

  The axial position where the first slider member is in contact with the first stop when the first shift fork is positioned at the reference position, the first shift position, and the second shift position, respectively. In the case of the position, the first displacement position, and the second displacement position, the first slider guide groove fixes the first slider member to a reference position when the drum member is positioned at the neutral position, and When the drum member is positioned at the first operation position, the first slider member is movable between a reference position and a first displacement position, and when the drum member is positioned at the third operation position, the first slider member is movable. The first slider member is fixed at a reference position, and when the drum member is positioned at the second operation position, the first slider member is fixed at the second displacement position, and the drum member is positioned at the fourth operation position. When Configured to have a groove shape for fixing the first slider member to the reference position.

  Alternatively, the first slider guide groove fixes the first slider member at the second displacement position when the drum member is positioned at the second speed change position, and the drum member is at the second speed change position. When positioned other than the position, the first slider member biased toward the first axial direction by the first slider member pushing spring remains in contact with the first stop portion. Thus, it may be configured to have a groove shape that allows the first shift fork to move in the axial direction following the movement in the axial direction.

  The axial position where the second slider member is in contact with the second stop when the second shift fork is positioned at the reference position, the third shift position, and the fourth shift position, respectively. When the position, the third displacement position, and the fourth displacement position are set, the second slider guide groove is located when the drum member is positioned between the first operation position and the second operation position with the neutral position interposed therebetween. The second slider member is fixed at a reference position, and when the drum member is positioned at the third operation position, the second slider member is fixed at the third displacement position, and the drum member is operated at the fourth operation position. When positioned, the second slider member is configured to have a groove shape that can move between a reference position and a fourth displacement position.

  Instead, the second slider guide groove fixes the second slider member at the third displacement position when the drum member is positioned at the third speed change position, and the drum member moves at the third speed change position. When positioned other than the position, the second slider member biased toward the second axial direction by the second slider member pushing spring remains in contact with the second stop portion. Thus, it may be configured to have a groove shape that allows the second shift fork to move in the axial direction following the movement in the axial direction.

  According to the drum-type speed change operation mechanism according to the first aspect of the present invention, the transmission rotation shaft is supported by the transmission rotation shaft so as not to be relatively rotatable and axially movable. A first shifter member that engages with each of the first and second speed change members that are rotatable relative to each other, a drum member that is rotated around an axis, a fork shaft, and an axial movement of the fork shaft. By a supported first shift fork, a first shift fork pushing spring that urges the first shift fork to the first axial direction, and a stop provided on a first boss of the first shift fork A slider member supported by the first boss portion so as to be movable in the axial direction in a state where a moving end toward the second side in the axial direction is defined; and the slider with a larger urging force than the first shift fork pushing spring A slider member pushing spring for urging the material toward the second axial direction, and the drum member has a first fork guide groove for guiding the first shift fork and a slider guide groove for guiding the slider member. The first fork guide groove is located at a reference position where the first shifter member does not engage with both the first and second speed change members when the drum member is located in the neutral position. When the drum member is positioned at the first shift position on one side around the axis from the neutral position, the first shifter member is between the reference position and the first shift position where the first shift member engages with the first shift member. When the drum member is positioned at the second operation position on the other side about the axis from the neutral position, the first shifter member is engaged with the reference position and the second speed change member when the drum member is positioned at the second operation position on the other side. The first shift fork is guided so as to be movable between two shift positions, and the slider guide groove is a reference of the first shifter member when the drum member is positioned at the first shift position. The slider member is guided so as not to obstruct the movement between the position and the first shift position, and the slider is biased by the slider member pushing spring when the drum member is positioned at the second shift position. Since the member allows the slider member to move in the axial direction so that the first shift fork can be pushed from the reference position to the second shift position, the fork shaft itself can be moved in the axial direction to obtain a standby action. Compared to the conventional configuration configured as described above, it is possible to reduce the size in the axial direction and reduce the operating force when shifting the drum member.

  According to the drum-type speed change operation mechanism according to the second aspect of the present invention, the transmission rotation shaft is supported so as not to rotate relative to the transmission rotation shaft and to be movable in the axial direction. A first shifter member that engages with the first and second speed change members that are relatively rotatable with each other, and is supported by the transmission rotation shaft so as not to be relatively rotatable and axially movable, and to the first and second axial directions. A second shifter member that engages with each of the third and fourth speed change members that are rotatable relative to the transmission rotation shaft by moving to the side, a drum member that is rotated around an axis, a fork shaft, First and second shift forks, which are supported by the fork shaft so as to be movable in the axial direction and move the first and second shifter members in the axial direction by their own axial movement, and the first shift shaft A first shift fork pushing spring for urging the shaft toward the second axial direction, a second shift fork pushing spring for urging the second shift fork toward the first axial direction, and the first shift fork A first slider member supported by the first boss portion so as to be movable in the axial direction in a state where a moving end toward the first axial direction is defined by a first stop portion provided on the first boss portion; A second slider supported by the second boss portion so as to be movable in the axial direction in a state where a moving end toward the second axial direction is defined by a second stop portion provided on the second boss portion of the second shift fork. A member, a first slider member pushing spring that pushes the first slider member toward the first axial direction with a biasing force larger than that of the first shift fork pushing spring, and larger than the second shift fork pushing spring The second thrust is applied by the urging force. A second slider member pushing spring that pushes the slider member toward the second axial direction, and the drum member has first and second fork guide grooves for guiding the first and second shift forks, respectively. First and second slider guide grooves for respectively guiding the first and second slider members are provided, and the first fork guide groove is formed when the drum member is positioned at the neutral position. When the member is located at a reference position where it does not engage with both the first and second speed change members and the drum member is located at the first operation position on one side around the axis from the neutral position, the first shifter member Is movable in the axial direction between a reference position and a first speed change position engaging with the first speed change member, and the drum member is positioned at a third operation position on one side around the axis from the first operation position. In When the first shifter member is positioned at the reference position and the drum member is positioned at the second operation position on the other side about the axis from the neutral position, the first shifter member is engaged with the reference position and the second transmission member. The first shifter member is positioned at the reference position when the drum member is positioned at the fourth operation position on the other side around the axis from the second operation position. As described above, the first shift fork is guided, and the first slider guide groove is in contact with the first stop portion when the drum member is positioned at the first shift position. In this state, the first shifter member can be moved in the axial direction between the reference position of the first shifter member and the first shift position, and when the drum member is positioned at the second shift position, the reference of the first shifter member Position and second shift The first slider member is guided so as not to disturb the movement between the positions, and the second fork guide groove is formed when the drum member is positioned at the first operation position, the neutral position, and the second operation position. Is located at a reference position where the second shifter member does not engage with both the third and fourth speed change members, and when the drum member is located at the third operation position, the second shifter member is the reference position. Between the position and the third speed change position engaging with the third speed change member, and when the drum member is positioned at the fourth operation position, the second shifter member is moved to the reference position and the third speed change position. The second shift fork is guided so as to be movable in the axial direction between the fourth speed change positions engaging with the fourth speed change member, and the second slider guide groove has the drum member at the third speed change position. When placed in When the drum member is positioned at the fourth shift position without interfering with the movement of the second shifter member between the reference position and the third shift position, the second slider member is moved to the second stop portion. Since the second slider member is guided so that the second shifter member can move between the reference position and the fourth shift position in the contacted state, the fork shaft itself is moved in the axial direction to wait. Compared to a conventional configuration configured to obtain an action, it is possible to reduce the size in the axial direction and reduce the operating force when shifting the drum member.

1 is a side view of a transmission to which a drum-type transmission according to Embodiment 1 of the present invention is applied. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and a part thereof is shown in a developed state. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 1, and shows a neutral state of the drum-type transmission. FIG. 5 is a development view of the drum member provided in the drum-type transmission according to the first embodiment, and shows a state in which the drum member is positioned at the neutral position. FIG. 6 is a cross-sectional view of the same cross section as FIG. 4 and shows a standby state in the speed change operation to the high speed gear. FIG. 7 is a development view showing a state where the drum member is positioned at a high speed position. FIG. 8 is a cross-sectional view of the same cross section as FIG. 4 and shows a standby state in the speed change operation to the low speed gear. FIG. 9 is a development view showing a state where the drum member is positioned at a low speed position. FIG. 10 is a cross-sectional view of the same cross section as that of FIG. 4 and shows a standby state in the speed change operation to the reverse gear. FIG. 11 is a development view showing a state where the drum member is positioned at the reverse movement position. FIG. 12 is a development view of a modified example of the drum member shown in FIG. 5 and shows a state in which the drum member is positioned at the neutral position. 13 is a cross-sectional view taken along line XIII-XIII in FIG. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 4 and shows a neutral state. FIG. 15 is a cross-sectional view of the same cross section as FIG. 14 and shows a reverse gear engagement state. FIG. 16 is a cross-sectional view of the same cross section as FIG. 14 and shows a parking stage engagement state. 17 is a cross-sectional view of the same cross section as FIG. 4 and shows a parking stage engagement state. FIG. 18 is a development view showing a state where the drum member is positioned at the parking position. FIG. 19 is a cross-sectional view of the same cross section as FIG. 14 and shows a standby state in the shifting operation to the parking stage. 20 is a cross-sectional view of a drum-type transmission according to a modification of the first embodiment, and shows a cross section corresponding to FIG. FIG. 21 is a cross-sectional view of the drum-type transmission according to Embodiment 2 of the present invention, showing a neutral state. FIG. 22 is a development view of a drum member provided in the drum-type transmission according to the second embodiment, and shows a state in which the drum member is positioned at a neutral position. FIG. 23 is a development view of a modified example of the drum member shown in FIG. 22 and shows a state where the drum member is positioned at the neutral position.

Embodiment 1
Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a side view of a transmission 800 provided with a drum-type transmission 1A according to the present embodiment.
2 to 4 are sectional views taken along lines II-II, III-III and IV-IV in FIG. 1, respectively.
FIG. 2 shows the following sub output shaft 850 in a developed state.

  The drum-type transmission 1A is preferably used for a traveling system transmission path of a working vehicle such as a tractor or a utility vehicle.

  The drum-type transmission device 1A can transmit transmission of rotational power between the first and second transmission rotations 810 and 820 shafts.

  Specifically, as shown in FIGS. 1 to 4, the drum-type transmission 1 </ b> A is not relatively rotatable with respect to the transmission gear 10 that is rotatably supported by the first transmission rotation shaft 810 and the second transmission rotation shaft 820. And a transmission gear 20 that is directly or indirectly meshed with the transmission gear 810, and a drum-type transmission operation mechanism 100A that selectively places the transmission gear 20 in a power transmission state.

  In the present embodiment, the transmission gear 10 has a transmission gear 10H for forward high speed, a transmission gear 10L for forward low speed, and a transmission gear 10R for reverse travel, and the transmission gear 20 A transmission gear 20H meshing with the gear 10H and forming a forward high-speed gear train with the transmission gear 10H, a transmission gear 20L meshing with the transmission gear 10L and forming a forward low-speed gear train with the transmission gear 10L, and the transmission A transmission gear 20 </ b> R that meshes with the gear 10 </ b> R via a reverse idle gear 15 (see FIG. 3) and forms a reverse gear train together with the transmission gear 10 </ b> R and the reverse idle gear 15.

  In the present embodiment, the second transmission rotating shaft 820 acts as a speed change input shaft for operatively inputting rotational power from a drive source (not shown) such as an engine, and the first transmission rotating shaft 810. Acts as a speed change output shaft for outputting the rotational power after speed change to the drive wheels.

  That is, as shown in FIGS. 1 and 2, the transmission 800 is configured to rotate around the transmission case 805 and the transmission case 805 with one end extending outwardly so as to be operatively connected to the drive source. The second transmission rotation shaft 820 that is rotatably supported and acts as a transmission input shaft, the first transmission rotation shaft 810 that is rotatably supported about the axis of the transmission case 805 and acts as a transmission output shaft, and the first 2, the drum type transmission 1 </ b> A that transmits the rotational power from the transmission transmission shaft 820 to the first transmission rotation shaft 810 in multiple stages.

  As shown in FIGS. 1 and 2, the transmission 800 further receives rotational power that is operatively input from a pair of left and right main output shafts 840 and the speed change output shaft (the first transmission rotary shaft 810). A differential gear device 830 that differentially transmits to a pair of left and right main output shafts, and a sub output shaft 850 that outputs rotational power of the speed change output shaft to a transmission path different from the main output shaft 840 are provided.

  When the transmission 800 is applied to a traveling system transmission path of a work vehicle, for example, the pair of main output shafts 840 act as a pair of left and right rear wheel drive shafts, and the sub output shaft 850 acts as a front wheel drive shaft. Can be made.

  The drum-type speed change operation mechanism 100A is configured to selectively bring the plurality of speed change gears 20 into a power transmission state and bring the speed change device 1A into a desired gear position engagement state.

  Specifically, as shown in FIGS. 2 to 4, the speed change operation mechanism 100 </ b> A is supported by the first transmission rotation shaft 810 so as not to be relatively rotatable and axially movable, and is selected by the speed change gear 820 by axial movement. Shifter member 110 that engages in a concave-convex manner, a fork shaft 120 parallel to the first transmission rotation shaft 810, a shift fork 130 supported on the fork shaft 120 so as to be movable in the axial direction, and the first transmission rotation shaft And a drum member 140 that is rotated around an axis parallel to 810.

  Specifically, shift uneven portions 112 and 12 are respectively provided on the opposed end surfaces of the shifter member 110 and the transmission gear 10, and the shifter member 110 is axially moved in a direction close to the transmission gear 10. Accordingly, the shift uneven portion 112 of the shifter member 110 is engaged with the shift uneven portion 12 of the transmission gear 10, so that the transmission gear 10 is moved through the shifter member 110 to the first position. 1 It becomes the power transmission state which rotates integrally with the transmission rotating shaft 810.

  As shown in FIGS. 2 to 4, in the present embodiment, the first transmission rotating shaft 810 includes a transmission gear 10 </ b> H, a transmission gear 10 </ b> R, and a transmission gear 10 </ b> L in order from the first side to the second side in the axial direction. Is arranged.

  The shift operation mechanism 100A is supported as the shifter member 110 so as to be relatively non-rotatable and movable in the axial direction between the transmission gear 10H and the transmission gear 10R. The first shifter member 110 (1) that engages with the transmission gear 10H and the transmission gear 10R in accordance with the movement toward the second side, and the first transmission rotating shaft 810 cannot rotate relative to the first transmission rotation shaft 810 at a position facing the transmission gear 10L. The second shifter member 110 is supported so as to be movable in the axial direction and engages with the transmission gear 10L in a concave-convex manner in accordance with movement toward the side close to the transmission gear 10L in the axial direction (in the illustrated form, the first axial direction side). (2).

  The first shifter member 110 (1) has a high-speed concavo-convex portion 112H that can be engaged with the concavo-convex portion 12H of the transmission gear 10H on the first axial end facing the transmission gear 10H. In addition, a reverse concavo-convex portion 112 </ b> R that can be engaged with the shift concavo-convex portion 12 </ b> R of the transmission gear 10 </ b> R is provided on the end surface on the second axial side facing the transmission gear 10 </ b> R.

  The second shifter member 110 (2) has a low-speed concavo-convex portion 112L that can engage with the shift concavo-convex portion 12L of the transmission gear 10L on the first axial end surface facing the transmission gear 10L. Yes.

  Further, as shown in FIG. 4, the shift operation mechanism 100 </ b> A has first and second shift forks 130 that move the first and second shifter members 110 (1) and 110 (2) in the axial direction, respectively. Two shift forks 130 (1) and 130 (2) are provided.

  As shown in FIG. 4 and the like, the first shift fork 130 (1) is formed on the drum member 140 and the first boss portion 132 (1) supported by the fork shaft 120 so as to be movable in the axial direction. The first fork guide groove 142 (1) has a first engagement pin portion 134 (1) and a first fork portion 136 (1) engaged with the first shifter member 110 (1). The first shifter member 110 (1) is moved in the axial direction on the first transmission rotating shaft 810 in accordance with the movement in the axial direction on the fork shaft 120.

More specifically, the first shift fork 130 (1) and the first shifter member 110 (1) are axially positioned, and the first shifter member 110 (1) is uneven with respect to both the transmission gear 10H and the transmission gear 10R. A non-engaging reference position, a high speed position at which the first shifter member 110 (1) engages with the transmission gear 10H, and a reverse position at which the first shifter member 110 (1) engages with the transmission gear 10R. Can take.
FIG. 4 shows a state in which the first shift fork 130 (1) and the first shifter member 110 (1) are located at a reference position.

  The second shift fork 130 (2) includes a second boss portion 132 (2) supported by the fork shaft 120 so as to be movable in the axial direction, and a second fork guide groove 142 (2) formed in the drum member 140. ) And a second fork portion 136 (2) engaged with the second shifter member 110 (2), and the fork The second shifter member 110 (2) is moved in the axial direction on the first transmission rotating shaft 810 in accordance with the axial movement on the shaft 120.

Specifically, the second shift fork 130 (2) and the second shifter member 110 (2) are related to the axial position, and the reference position where the second shifter member 110 (2) does not engage with the transmission gear 10L. In addition, the second shifter member 110 (2) can be at a low speed position where the gear shift gear 10L is engaged with the concave and convex portions.
FIG. 4 shows a state in which the second shift fork 130 (2) and the second shifter member 110 (2) are located at a reference position.

The drum member 140 is rotated about an axis in accordance with a speed change operation.
In the present embodiment, as shown in FIG. 4, the drum-type shift operation mechanism 100 </ b> A is provided with an operation shaft 150 that receives a shift operation, and the drum member 140 is operatively connected to the operation shaft 150. ing.
In the present embodiment, the operation shaft 150 is operatively connected to the drum member 140 via a speed increasing gear train 155.

The operation shaft 150 is supported by a housing (a mission case 805 in the present embodiment) so as to be rotatable about an axis with one end portion extending outward.
As shown in FIGS. 1 and 4, the operation shaft 150 is rotated around the axis by an electric motor 155, for example.
In this case, an angle sensor 156 for detecting the position around the axis of the drum member 140 is provided.

  Alternatively, the operation shaft 150 can be rotated around the axis by human operation. In this case, the electric motor 155 is removed, and an operation arm (not shown) is attached to one end of the operation shaft 150.

  As shown in FIG. 4, the drum member 140 includes a drum body 141 in which fork guide grooves (in the present embodiment, the first and second fork guide grooves 142 (1) and 142 (2)) are formed. And a drum shaft 148 that supports the drum body 141 coaxially with the drum body 141.

  As shown in FIG. 4, the drum-type speed change operation mechanism 100A further includes a first shift fork pushing spring 160 (1) that pushes the first boss portion 132 (1) toward the first axial direction. The first boss portion 132 (1) includes a slider member 170 that is externally supported so as to be movable in the axial direction, and a slider member pushing spring 180 that pushes the slider member 170 toward the second side in the axial direction. .

  When the first shift fork 130 (1) is in a free state, the first shift fork pushing spring 160 (1) reaches the high speed position where the first shifter member 110 (1) engages with the transmission gear 10H. The first boss portion 132 (1) is set to be pushed toward the first side in the axial direction with an urging force that can be moved.

  Specifically, the first shift fork pushing spring 160 (1) has a second end portion in the axial direction as a fixed end portion that is engaged with an engaging member 126 provided on the fork shaft 120, and The end portion on the first axial side is a movable end portion engaged with the end surface on the second axial side of the first boss portion 132 (1).

  The slider member 170 is axially disposed on the first boss portion 132 (1) in a state where a moving end toward the second axial direction is defined by a stop portion 133 provided on the first boss portion 132 (1). Further, the position in the axial direction is regulated by a slider guide groove 144 provided in the drum member 140 so as to be movable.

  Specifically, the slider member 170 includes a slider main body 172 externally inserted in the first boss portion 132 (1) so as to be movable in the axial direction, and a slider engagement pin portion 174 engaged in the slider guide groove 144. have.

  The slider member pushing spring 180 is configured to push the slider member 170 toward the second side in the axial direction with a larger biasing force than the first shift fork pushing spring 160 (1).

  That is, the slider member pushing spring 180 moves the first shift fork 130 (1) to the first axial side when the first shift fork 130 (1) and the slider member 110 (1) are free. With an urging force that can move the first shifter member 110 (1) to the reverse movement position that engages with the transmission gear 10R against the urging force of the urging first shift fork pushing spring 160 (1). The first boss portion 132 (1) is set to be pushed to the second side in the axial direction through the slider member 170.

  Specifically, the slider member pushing spring 180 has a first axial end that is a fixed end locked by a locking member 127 provided on the fork shaft, and an axial second side. The end portion of the slider member 170 is a movable end portion engaged with the end surface on the first axial side of the slider member 170.

  In the present embodiment, as shown in FIG. 4, the drum-type speed change operation mechanism 100A further includes the second boss in the direction in which the second shifter member 110 (2) is pressed toward the speed change gear 10L. A second shift fork pushing spring 160 (2) for pushing the portion 132 (2) is provided.

  As described above, in the present embodiment, the transmission gear 10L is located on the first axial side of the second shifter member 110 (2), and accordingly, the second shift fork pushing spring 160 (2). Pushes the second boss 132 (2) toward the first side in the axial direction.

  Specifically, the second shift fork pushing spring 160 (2) has an end portion on the second side in the axial direction as a fixed end portion engaged with an engaging member 128 provided on the fork shaft 120, and The end portion on the first axial side is a movable end portion engaged with the end surface on the second axial side of the second boss portion 132 (2).

  When the second shift fork 130 (29) is free, the second shift fork pushing spring 160 (2) is moved to a low speed position where the second shifter member 110 (2) engages with the transmission gear 10L. The second boss portion 132 (2) is set to be pushed by an urging force that can be moved.

Here, the shape of the first fork guide groove 142 (1), the second fork guide groove 142 (2), and the slider guide groove 144 will be described.
FIG. 5 shows a development view of the drum member 140.

  The drum member 140 is configured to take an operation position around an axis corresponding to a shift stage (including a neutral stage) that the drum type transmission 1A can take.

  In the present embodiment, the drum-type transmission 1A is configured to be able to take a neutral stage, a forward high speed stage, a forward low speed stage, and a reverse stage, and thus the drum member 140 is configured around the axis line. A neutral position N, a high speed position H, a low speed position L, and a reverse position R are configured.

  Specifically, in the present embodiment, the drum member 140 assumes a high speed position H when rotated from the neutral position N to one side around the axis, and low speed when rotated further from the high speed position H to one side around the axis. It is configured to take a position L and take a reverse position R when rotated from the neutral position N to the other side around the axis.

The drum type transmission 1A can further take a parking stage, and the drum member 140 can take a parking position P in addition to the operation position.
As shown in FIG. 5, in the present embodiment, the drum member 140 is configured to take the parking position P when it is further rotated from the reverse position R to the other side around the axis.
A configuration for making this parking state appear will be described later.

  As shown in FIG. 5, the first fork guide groove 142 (1), the slider guide groove 144 and the second fork guide groove 142 (2) have the drum member 140 in a neutral position N, a high speed position H, and a low speed. When positioned at the position L, the reverse position R, and the parking position P, the neutral engagement portion and the high-speed engagement are engaged with the corresponding engagement pin portions 134 (1), 174, 134 (2), respectively. It has a part, an engagement part at low speed, an engagement part at reverse travel, and an engagement part at parking.

First, the groove shape of the first fork guide groove 142 (1) will be described.
As shown in FIG. 5, the neutral engagement portion 142 (1) N of the first fork guide groove 142 (1) is fixed to the first engagement portion 142 (1) so as to fix the first shift fork 130 (1) at a reference position. It has a groove shape that holds the mating pin portion 134 (1).

  The engagement portion 142 (1) H at high speed is such that the moving end of the first shift fork 130 (1) toward the first axial direction becomes the high speed position and the moving end toward the second axial direction becomes the reference position. Further, it has a groove shape for guiding the first engagement pin 134 (1).

  The transition portion located between the neutral engagement portion 142 (1) N and the high speed engagement portion 142 (1) H is a movement end of the first shift fork 130 (1) toward the second side in the axial direction. While being fixed at the reference position, the moving end of the first shift fork 130 (1) in the first axial direction is changed from the reference position to the high speed position in accordance with the rotation from the neutral position N to the high speed position H of the drum member 140. It has such a groove shape.

  The low speed engagement portion 142 (1) L has a groove shape that holds the first engagement pin portion 134 (1) so as to fix the first shift fork 130 (1) at a reference position. Yes.

  The transition portion between the high-speed engagement portion 142 (1) H and the low-speed engagement portion 142 (1) L is the reference position of the moving end of the first shift fork 130 (1) toward the second side in the axial direction. The moving end of the first shift fork 130 (1) in the first axial direction is changed from the high speed position to the reference position in accordance with the rotation of the drum member 140 from the high speed position H to the low speed position L. It has a groove shape.

  The reverse engagement portion 142 (1) R is a groove that uses the movement end of the first shift fork 130 (1) in the axial direction first side as a reference position and the movement end in the axial direction second side as a reverse movement position. It has a shape.

  The transition part located between the neutral engagement part 142 (1) N and the reverse engagement part 142 (1) R is the movement end of the first shift fork 130 (1) toward the first side in the axial direction. While being fixed at the reference position, the moving end of the first shift fork 130 (1) in the second axial direction is changed from the reference position to the reverse position in accordance with the rotation from the neutral position N to the reverse position R of the drum member 140. It has such a groove shape.

  The parking engaging portion 142 (1) P has a groove shape for fixing the first shift fork 130 (1) to a reference position.

  The transition portion between the reverse engagement portion 142 (1) R and the parking engagement portion 142 (1) P is the reference position of the movement end of the first shift fork 130 (1) toward the first side in the axial direction. The moving end of the first shift fork 130 (1) in the second axial direction is changed from the reverse position to the reference position in accordance with the rotation from the reverse position R to the parking position P of the drum member 140. It has a groove shape.

Next, the groove shape of the slider guide groove 144 will be described.
The slider guide groove 144 is permitted by the high speed engagement portion 142 (1) H of the first fork guide groove 142 (1) when the first drum member 140 is positioned at the high speed position H. The slider member 170 is fixed at a retracted position that does not limit the axial movement range of the one shift fork 130 (1).

  Specifically, the axis on which the slider member 170 is positioned when the first shift fork 130 (1) is positioned at the reference position, the high speed position, and the reverse position while the slider member 170 is in contact with the stop portion 133. The direction positions are defined as a reference position, a first displacement position, and a second displacement position, respectively (see FIG. 5).

  In the present embodiment, as shown in FIG. 5, the high speed engagement portion 144H of the slider guide groove 144 is configured to fix the slider member 170 at the first displacement position.

  That is, in the present embodiment, the slider guide groove 144 is configured to fix the slider member 170 to the first displacement position as the retracted position when the drum member 140 is positioned at the high speed position H. Has been.

In the present embodiment, the slider guide groove 144 further has the following groove shape.
That is, as shown in FIG. 5, the neutral engaging portion 144N has a groove shape that holds the slider engaging pin portion 174 so as to fix the slider member 170 at a reference position.

  The transition portion between the neutral engagement portion 144N and the high speed engagement portion 144H guides the slider member 170 from the reference position to the first displacement position according to the rotation from the neutral position N to the high speed position H of the drum member 140. It has such a groove shape.

  The low speed engagement portion 144L has a groove shape that holds the slider engagement pin portion 174 so as to fix the slider member 170 at a reference position.

  The transition portion between the high speed engagement portion 144H and the low speed engagement portion 144L guides the slider member 170 from the first displacement position to the reference position in accordance with the rotation of the drum member 140 from the high speed position H to the low speed position L. It has such a groove shape.

  The reverse engagement portion 144R has a groove shape in which the moving end on the first axial direction side of the slider member 170 is a reference position and the moving end on the second axial direction is a second displacement position.

  The transition portion between the neutral engagement portion 144N and the reverse engagement portion 144R is fixed in the axial direction of the slider member 170 while the moving end of the slider member 170 toward the first axial direction is fixed at a reference position. The groove shape is such that the moving end to the second side is changed from the reference position to the second displacement position in accordance with the rotation from the neutral position N to the reverse position R of the drum member 140.

  The parking engaging portion 144P has a groove shape that fixes the slider member 170 at a reference position.

  The transition portion between the reverse engagement portion 144R and the parking engagement portion 144P is fixed in the axial direction of the slider member 170 while the moving end of the slider member 170 toward the first axial direction is fixed at a reference position. A groove shape is formed such that the moving end to the second side changes from the second displacement position to the reference position in accordance with the rotation from the reverse position R to the parking position P of the drum member 140.

Next, the groove shape of the second fork guide groove 142 (1) will be described.
The second fork guide groove 142 (1) allows the second shift fork 130 (2) to move in the axial direction between the reference position and the low speed position when the drum member 140 is positioned at the low speed position L. On the other hand, when the drum member 140 is positioned at an operating position other than the low speed position L, the second shift fork 130 (2) has a groove shape that fixes the reference position.

  That is, as shown in FIG. 5, the second shift fork 130 (2) is fixed at the reference position in the region from the high speed engagement portion 142 (2) H to the parking engagement portion 142 (2) P. Thus, it has a groove shape that holds the second engagement pin portion 134 (2).

  On the other hand, the low-speed engagement portion 142 (2) L has the moving end of the second shift fork 130 (2) toward the first axial direction as the low speed position and the moving end toward the second axial direction as the reference position. It has a groove shape that

  The transition portion between the high speed engagement portion 142 (2) H and the low speed engagement portion 142 (2) L is a movement end of the second shift fork 130 (2) toward the second side in the axial direction. While being fixed at the reference position, the moving end of the second shift fork 130 (2) in the first axial direction is changed from the reference position to the low speed position according to the rotation of the drum member 140 from the high speed position H to the low speed position L. It has such a groove shape.

  The drum-type shift operation mechanism 100A having such a configuration can exhibit a standby action during a shift operation.

First, the standby operation in the shifting operation to the high speed stage will be described.
When the drum member 140 is positioned at the neutral position N, as described above, the first shift fork 130 (1) and the second shift fork 130 (2) are fixed at the reference position ( (See FIG. 5).
Accordingly, the first and second shifter members 110 (1) and 110 (2) are both positioned at the reference position, and the drum-type transmission 1A is in the neutral stage (see FIG. 4).

  When the drum member 140 is operated from the neutral position N to the high speed position H, as described above, the axial direction of the first shift fork 130 (1) regulated by the first fork guide groove 142 (1). The moving end on the first side changes from the reference position to the high speed position according to the rotation from the neutral position N to the high speed position H of the drum member 140, and when the drum member 140 is positioned at the high speed position H, The shift fork 130 (1) is movable in the axial direction between the reference position and the high speed position.

  On the other hand, when the drum member 140 is positioned at the high speed position H, the slider member 170 is fixed at the retracted position (first displacement position in the present embodiment) by the slider guide groove 144.

  In this state, the force by which the slider member pushing spring 180 pushes the slider member 170 to the second axial direction does not act on the first boss portion 132 (1), and the first boss portion 132. Only the urging force to the second side in the axial direction by the first shift fork pushing spring 160 (1) acts on (1).

  Accordingly, when the drum member 140 is positioned at the high speed position H, the first shift fork 130 (1) and the first shifter member 110 (1) are attached to the first shift fork pushing spring 160 (1). It becomes a state that can be moved to a high speed position by the force.

  Here, when the drum member 140 is positioned at the high speed position H, the relative position around the axis between the high speed uneven portion 112H of the first shifter member 110 (1) and the speed change uneven portion 12H of the transmission gear 10H. Is the position where the concave and convex portions can be engaged with each other, the concave and convex portions for high speed 112H and the convex and concave portions for shifting 12H are immediately engaged with the concave and convex portions so that the transmission gear 10H is in a transmission state, and the drum-type transmission 1A immediately A step engagement state is established.

However, depending on the relative positions of the first shifter member 110 (1) and the transmission gear 10H around the axis, the projections of the high-speed irregularities 112H and the transmission gear 10H of the first shifter member 110 (1) A situation may occur in which the convex portions of the concavo-convex portion 12H are abutted against each other (see FIG. 6).
In this case, the first shifter member 110 (1) cannot immediately move to the high speed position.

  Even if such a situation occurs, in the present embodiment, the drum member 140 can be rotated in advance to the high speed position H (see FIG. 7), and then the first shift fork pushing spring 160 ( The first shift fork 130 (1) and the first shifter member 110 (1) are moved to the high speed position by the urging force of 1) to complete the shift operation to the high speed stage of the drum type transmission 1A. Can do.

  That is, when a situation occurs in which the convex portions are brought into contact with each other, the first shifter member 110 (1) and the first shift fork 130 (1) are connected to the first shift fork as shown in FIGS. In a state where the urging force toward the first axial direction by the push spring 160 (1) continues to be received, the projections are fixed at the reference position by abutment.

  Therefore, when the first shifter member 110 (1) and the transmission gear 10H rotate relative to each other around the axis line and the projections are not matched, the first shift fork pushing spring 160 (1) is attached. The first shifter member 110 (1) is pushed to the high speed position via the first shift fork 130 (1) by the force and engages with the transmission gear 10H so that the high speed of the drum type transmission 1A is high. The shift operation to the gear is completed (standby action to the high gear).

  When the drum member 140 is positioned at the high speed position H, as described above, the second shift fork 130 (2) and the second shifter member 110 (2) are fixed at the reference position, The transmission gear 10L is in a non-transmission state.

Next, the standby action in the shifting operation to the low speed stage will be described.
When the drum member 140 is positioned at the low speed position L, the second shift fork 130 (2) (and the second shifter member 110 (2)) are moved by the second shift fork pushing spring 160 (2). In a state of being biased toward the low-speed position on the second side in the axial direction, the state is movable in the axial direction between the reference position and the low-speed position.

  Here, when the drum member 140 is positioned at the low speed position L, the relative position around the axis between the low speed uneven portion 112L of the second shifter member 110 (2) and the speed change uneven portion 12L of the transmission gear 10L. , The low-speed concavo-convex portion 112L and the shift concavo-convex portion 12L immediately engage with the concavo-convex portion, and the transmission gear 10L is brought into a transmission state, so that the drum-type transmission 1A immediately becomes low-speed. A step engagement state is established.

  On the other hand, when the convex part of the uneven part for low speed 112L of the second shifter member 110 (2) and the convex part of the uneven part for shifting 12L of the transmission gear 10L are brought into contact with each other (FIG. 8), the second shifter member 110 (2) (and the second shift fork 130 (2)) receives a biasing force toward the first axial direction by the second shift fork pushing spring 160 (2). In this state, the drum is fixed at the reference position (see FIG. 8), and only the drum member 140 can be rotated to the low speed position L (see FIG. 9).

  Then, when the second shifter member 110 (2) and the transmission gear 10L rotate relative to each other around the axis and the butting of the convex portions is eliminated, the second shift fork pushing spring 160 (2) is attached. The second shifter member 110 (2) is pushed to the low speed position by the force and engages with the unevenness of the transmission gear 10L, and the shifting operation to the low speed stage of the drum type transmission 1A is completed (to the low speed stage). Standby action).

  When the drum member 140 is positioned at the low speed position L, as described above, the first shift fork 130 (1) and the first shifter member 110 (1) are fixed at the reference position, The transmission gear 10H and the transmission gear 10R are in a non-transmission state.

Next, the standby operation in the shifting operation to the reverse gear will be described.
When the drum member 140 is positioned at the reverse drive position R, the first shift fork 130 (1) is urged toward the first axial direction by the first shift fork pushing spring 160 (1). In this state, it is possible to move in the axial direction between the reference position and the reverse position.

  On the other hand, the slider member 170 is urged toward the second axial direction by the slider member pressing spring 180 and is movable in the axial direction between the reference position and the second displacement position. .

  As described above, the urging force of the slider member pushing spring 180 is larger than the urging force of the first shift fork pushing spring 160 (1), and therefore the drum member 140 is positioned at the reverse position R. In this case, the first shift fork 130 (1) is sized according to the difference between the urging force of the slider member pushing spring 180 and the urging force of the first shift fork pushing spring 160 (1). It can be moved to the reverse position on the second axial side by the urging force.

  Here, when the drum member 140 is positioned at the reverse position R, the relative position around the axis between the reverse uneven portion 112R of the first shifter member 110 (1) and the shift uneven portion 12R of the transmission gear 10R. Is the position where the concave / convex engagement is possible, the reverse concave / convex portion 112R and the shift concave / convex portion 12R immediately engage with the concave / convex portion, and the transmission gear 10R enters the transmission state, and the drum transmission 1A immediately reverses. A step engagement state is established.

  On the other hand, when a situation occurs in which the convex portion of the reverse uneven portion 112R of the first shifter member 110 (1) and the convex portion of the shift uneven portion 12R of the transmission gear 10R are brought into contact with each other, The first shifter member 110 (1) (and the first shift fork 130 (1)) has a difference between the biasing force of the slider member pushing spring 180 and the biasing force of the first shift fork pushing spring 160 (1). Accordingly, the drum member 140 is fixed to the reference position while being biased toward the second axial direction by a biasing force of a magnitude corresponding to (see FIG. 10), and only the drum member 140 can be rotated forward to the reverse position R. (See FIG. 11).

  Then, when the first shifter member 110 (1) and the transmission gear 10R rotate relative to each other around the axis and the abutment between the convex portions is resolved, the urging force of the slider member pushing spring 180 and the first The first shifter member 110 (1) is pushed to the reverse position via the first shift fork 130 (1) by the biasing force having a magnitude corresponding to the difference between the biasing force of the shift fork pushing spring 160 (1). It is moved to engage with the transmission gear 10R in a concave-convex manner, and the shift operation to the reverse gear of the drum type transmission 1A is completed (standby operation to the reverse gear).

  As described above, in the drum-type speed change operation mechanism 100A, the first shift fork push spring 160 (1) biases the first shift fork 130 (1) toward the high-speed position on the first side in the axial direction. In addition, the first shift is performed via the slider member 170 biased to the second axial direction by the slider member pushing spring 180 having a larger biasing force than the first shift fork pushing spring 160 (1). The fork 130 (1) is configured to be urged toward the reverse position on the second axial side, and the slider member pushing spring 180 is attached when the drum member 140 is positioned at the high speed position. The slider member 180 is moved by the slider guide groove 144 of the drum member 140 so that force does not act on the first shift fork 130 (1). By fixing the avoidance position, thereby revealing the standby action to the high speed stage by the biasing force of the first shift fork pusher spring 160 (1).

  When the drum member 140 is positioned at the reverse position, both the slider member pushing spring 180 and the first shift fork pushing spring 160 (1) act on the first shift fork 130 (1). In this state, the first shifter member 110 (1) and the first shift fork 130 (1) can move in the axial direction between a reference position and a reverse position, and the slider guide groove 144 of the drum member 140 and The first fork guide groove 142 (1) is formed, and thereby the standby action for the reverse gear is revealed by the difference in the urging force between the two push springs 180 and 160 (1).

  Therefore, as compared with the conventional configuration configured to obtain a standby action by moving the fork shaft itself in the axial direction, it is possible to reduce the size in the axial direction and reduce the operating force.

  In the present embodiment, the slider guide groove 144 fixes the slider member 170 to a reference position when the drum member 140 is positioned at the neutral position N, and the drum member 140 is positioned at the high speed position H. When the drum member 140 is positioned at the low speed position L, the slider member 170 is fixed at the reference position, and the drum member 140 is fixed at the reference position. Is moved in the axial direction between the reference position and the second displacement position, and when the drum member 140 is positioned at the parking position P, the slider member 170 is moved to the reverse position R. Although 170 is configured to be fixed at the reference position, the present invention is not limited to such a form.

  For example, when the drum member 140 is positioned at the high speed position H, the slider member 170 is fixed at the retracted position (for example, the first displacement position), while the drum member 140 is positioned at a position other than the high speed position H. In this case, the first shift fork 130 (1) is kept in a state where the slider member 170 biased toward the second axial direction by the slider member pushing spring 180 is in contact with the stop portion 133. It is also possible to employ a slider guide groove 145 formed to allow movement in the axial direction following the movement in the axial direction.

FIG. 12 is a development view of the drum member 140 provided with an example of the slider guide groove 145.
In the example shown in FIG. 12, the high speed engaging portion 145H of the slider guide groove 145 fixes the slider member 170 at the retracted position (for example, the first displacement position), and the neutral engaging portion 145N is at the low speed. The engagement portion 145L, the reverse engagement portion 145R, and the parking engagement portion 145P have groove shapes that allow the slider member 170 to move in the axial direction between the first displacement position and the second displacement position. Have.

  The drum-type speed change operation mechanism 100A further includes a detent mechanism 700 that locks the drum member 140 at each of the operation positions.

FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG.
As shown in FIGS. 4 and 13, the detent mechanism 700 is supported by a detent plate 710 supported by the drum member 140 so as not to rotate relative to the drum member 140, and a detent shaft 725 parallel to the drum member 140. A detent arm 720 and a detent spring 730 are provided.

The detent plate 710 has a plurality of detent recesses 712 that open radially outward and correspond to the operation positions that the drum member 140 can take.
As described above, in the present embodiment, the drum member 140 includes the neutral position N, the high speed position H that is located when the drum member 140 is operated from the neutral position N to one side around the axis, and the high speed position H is one around the axis. A low speed position L when operated to the side, a reverse position R when operated from the neutral position N to the other side around the axis, and a position when operated from the reverse position R to the other side around the axis The parking position P to be taken can be taken.

  Accordingly, the plurality of detent recesses 712 include a neutral position recess 712N, a high speed position recess 712H, a low speed position recess 712L, a reverse position recess 712R, and a parking position recess 712P.

The plurality of detent recesses 712 are arranged in the circumferential direction so that the recesses corresponding to the operation position of the drum member 140 are positioned at a detent position 715 facing the free end of the detent arm 712 around the axis. Yes.
FIG. 13 shows a state in which the drum member 140 is positioned at the neutral position N, and accordingly, the corresponding neutral position recess 712N is positioned at the detent position 715.

  More specifically, the neutral position recess 712N, the high speed position recess 712H, the low speed position recess 712L, the reverse position recess 712R, and the parking position recess 712P are respectively configured such that the drum member 140 is in the neutral position N, the high speed position H, and the low speed. When positioned at the position L, the reverse position R, and the parking position P, they are disposed at the detent position 715.

  The detent arm 720 has an engaging portion 722 that is rotatably supported by the detent shaft 725 at the base end and can be engaged with the detent recess 712 positioned at the detent position 715 at the free end. .

  In the present embodiment, the detent arm 720 has a roller that can rotate around a rotation axis parallel to the detent shaft 712 at the free end, and the roller acts as the engagement portion 722. ing.

  The detent spring 730 biases the detent arm 720 about the detent shaft 725 so that the engaging portion 722 of the detent arm 720 is pressed toward the detent recess 712 located at the detent position 715. .

  By providing the detent mechanism 700, it is possible to effectively prevent the drum member 140 from rotating unexpectedly from the operation position.

Hereinafter, the parking structure of the drum type transmission 1A will be described.
FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG.
FIG. 14 also shows an A1-A1 arrow view and an A2-A2 arrow view in FIG.

  As shown in FIGS. 4 and 14, in the drum-type transmission 1 </ b> A, the shift transmission fork (second shift fork 130 (2)) moves in the axial direction and the corresponding transmission gear (the transmission gear 10 </ b> L). The shifter member (the second shifter member 110 (2)) that brings the transmission gear into a power transmission state by engaging with the recesses and projections is provided with a parking unevenness portion 112P that faces radially outward.

  In addition, the drum-type transmission device 1A has a locking mechanism that forcibly engages the parking uneven portion 112P and forcibly stops the rotation of the shifter member (the second shifter member 130 (2)). 500 is provided.

  As described above, the drum-type transmission 1A also serves as a parking gear using the shifter member (the second shifter member 110 (2)) that engages and disengages power transmission by the corresponding transmission gear (the transmission gear 10L). Thus, the cost can be reduced by reducing the number of parts and the size in the axial direction can be reduced.

  That is, conventionally, a transmission gear that is rotatably supported by the first transmission rotation shaft, a transmission gear that is supported relatively non-rotatably by the second transmission rotation shaft, and meshed directly or indirectly with the transmission gear; A shifter member supported so as not to be rotatable relative to the first transmission rotation shaft and movable in the axial direction, a drum member rotated around the axis, a fork shaft parallel to the drum member, and an axial direction of the fork shaft A shift fork that is movably supported, and the shift fork whose axial position is regulated by a fork guide groove formed in the drum member is moved in the axial direction in accordance with the rotation of the drum member, and the shifter A member is engaged with the transmission gear in a concavo-convex manner so that power is transmitted between the first and second transmission rotation shafts via the transmission gear and the transmission gear. As a structure for obtaining a parking stage in the drum type transmission, the parking gear, which is a member different from the shifter member, is provided on the first transmission rotating shaft so as not to be relatively rotatable, and the parking gear is forcibly stopped. It was common to configure to be in a state.

  However, in this conventional configuration, the parking gear separated from the transmission gear and the shifter member is moved to the first transmission rotating shaft at a position displaced in the axial direction from the transmission gear and the shifter member. It is necessary to provide it, and the enlargement is caused in the axial direction.

  On the other hand, in the drum type transmission 1A according to the present embodiment, it is not necessary to provide a parking gear which is a separate member from the shifter member (the second shifter member 110 (2)), and therefore, the axial direction is not related. The apparatus can be reduced in size, and the cost can be reduced by reducing the number of parts by eliminating the need for a parking gear.

  As shown in FIG. 14, the lock mechanism 500 can swing about a swing axis 505 parallel to the first transmission rotation shaft 810 that supports the second shifter member 110 (2), and is provided at a free end. A parking operation arm 510 having an engagement portion 515 that can be engaged with the parking uneven portion 112P, and a parking release spring 520 that biases the parking operation arm 510 in the parking release direction around the swing axis 505 (FIG. 3) and a parking pushing member 530.

  In the parking operation arm 510, the engagement portion 515 is engaged with the parking uneven portion 112P around the swing axis 505 to force the second shifter member 110 (2) to stop rotating. The parking position to be taken and the parking release position where the engaging portion 515 is spaced radially outward from the parking uneven portion 112P can be taken.

  The parking push member 530 uses the movement of the drum member 140 about the axis to the parking position P to move the parking operating arm 510 against the biasing force of the parking release spring 520. Push toward.

  In this embodiment, as shown in FIGS. 4 and 14, the parking push member 530 includes a main body portion 532 supported by the drum member 140, and extends radially outward from the main body portion 532. And a cam pushing portion 535.

FIGS. 15 and 16 are cross-sectional views of the same cross section as FIG. 14, and show cross-sectional views in a state where the drum member 140 is positioned at the speed change position (reverse position R) and the parking position P, respectively.
FIG. 17 is a cross-sectional view of the same cross section as FIG. 4, and shows a cross-sectional view in a state where the parking stage is engaged.
FIG. 18 is a development view showing a state where the drum member 140 is positioned at the parking position P.

  As shown in FIGS. 14 and 15, the cam pusher 530 is configured to operate the parking operation arm when the drum member 140 is in a neutral position N and a shift position (reverse drive position R in the illustrated form). As shown in FIG. 16, the drum member 140 is rotated against the parking position P and resists the biasing force of the parking release spring 520 (see FIG. 3). The parking operation arm 510 is configured to push toward the parking position.

In this embodiment, as shown in FIGS. 3 and 14 to 16, the parking operation arm 510 is a boss portion that is externally rotatably attached to a pivot shaft 506 that defines the swing axis 505. 512 and an arm portion 514 extending radially outward from the boss portion 512, and the engagement portion 515 on the side of the free end portion of the arm portion 514 that faces the parking uneven portion 112 </ b> P. And a pressure receiving surface 516 with which the cam pushing portion 535 engages is provided on the side of the arm portion 514 opposite to the parking uneven portion 112P.
A reference numeral 508 in FIGS. 3 and 14 to 16 is a bushing that makes the boss portion 512 relatively rotatable with respect to the pivot shaft 506.

  In the present embodiment, as shown in FIG. 3, the idler shaft 16 that supports the reverse idle gear 15 forming the reverse gear train supports the parking operation arm 510 in a swingable manner. It is used as the shaft 506.

  As shown in FIG. 3 and the like, the parking release spring 520 has one end operatively connected to the parking operating arm 510 and the other end connected to the pivot shaft 506 (via the pin 522 in this embodiment). The coil spring is inserted into the pivot shaft 506 in the operatively connected state.

  In the present embodiment, as described above, when the drum member 140 is rotated from the neutral position N to the other side around the axis, the drum member 140 takes the reverse position R and from the reverse position R to the other side around the axis further. The parking position P is taken.

  Therefore, the cam pushing portion 535 does not engage with the pressure receiving surface 516 when the drum member 140 is positioned at the neutral position N (FIG. 14) and the reverse position R (FIG. 16), and the drum When the member 140 is rotated from the reverse position R toward the parking position P, the member 140 is engaged with the pressure receiving surface 516, and the parking operation arm 510 is moved to the parking position against the urging force of the parking release spring 520. Push toward.

  Thus, in the present embodiment, the parking push member 530 is supported by the drum member 140, and thereby, the parking member is utilized by utilizing the rotation of the drum member 140 to the parking position P. The lock mechanism 500 that pushes the operating arm 510 toward the parking position can be made compact.

  The drum-type transmission 1 according to the present embodiment further includes the following configuration in order to achieve a standby action in the shifting operation to the parking stage.

  In other words, in the present embodiment, the main body 532 of the parking push member 530 is extrapolated to the drum member 140 so as to be relatively rotatable.

  In addition, as shown in FIGS. 4 and 14 to 16, the parking push member 530 and the drum member 140 are operatively connected at one end to the parking push member 530 and at the other end ( In this embodiment, it is connected via a parking coil spring 540 externally attached to the drum member 140 in a state of being operatively connected to the drum member 140 (via a pin 542).

  When the circumferential load applied to the cam pushing portion 535 is a predetermined value or less, the parking coil spring 540 causes the parking pushing member 530 to rotate integrally with the rotation of the drum member 140 around the axis. And the drum member 140 is elastically deformed when the circumferential load applied to the cam pushing portion 535 exceeds a predetermined value, and the drum member 140 is moved against the parking pushing member 530. It is configured to allow a preceding relative rotation around the axis.

  In this embodiment, the parking coil spring 540 is configured to be elastically deformed in the diameter-reducing direction when the drum member 140 is rotated with respect to the parking push member 530 in a preceding relative rotation. .

By providing such a configuration, a standby action can be obtained in the shifting operation to the parking stage.
That is, when the cam pushing portion 535 swings the parking operation arm 510 toward the parking position in response to the rotation of the drum member 140 to the parking position P, the engagement of the parking operation arm 510 is performed. It is assumed that the portion 515 is abutted against the convex portion of the parking uneven portion 112P of the second shifter member 110 (2) and the parking operation arm 510 cannot swing to the parking position (see FIG. 19).

In this case, a circumferential load exceeding the predetermined value is applied to the cam pushing portion 535.
Accordingly, as shown in FIG. 19, the drum member 140 rotates relative to the parking push member 530 around the axis to the parking position P while elastically deforming the parking coil spring 540.

  The parking coil spring 540 in the elastically deformed state has an elastic force that urges the parking pushing member 530 in a direction to follow the drum member 140, and the engaging portion 515 and the parking unevenness When the portion 112P is aligned, the elastic force causes the parking operation arm 510 to swing to the parking position against the biasing force of the parking release spring 520, and the engaging portion 515 and the parking uneven portion. 112P engages with the concave and convex portions, and the shifting operation to the parking stage is completed (see FIG. 16).

  In the present embodiment, as shown in FIG. 16, when the cam pushing portion 535 positions the parking operation arm 510 in the parking position and the drum type transmission 1A enters the parking stage engagement state. Further, the direction of the reaction force acting on the cam pushing portion 535 from the pressure receiving surface 516 is substantially opposite to the direction in which the cam pushing portion 535 extends radially outward with respect to the axis of the drum member 140. (Hereinafter referred to as a “replacement” configuration by the cam pushing portion 535).

  By providing the “replacement” configuration by the cam pushing portion 535, it is possible to effectively release the engagement portion 515 of the parking operation arm 510 and the uneven portion 112P of the parking operation unexpectedly. It can be prevented or reduced.

  Specifically, when the drum-type transmission 1A is used for a traveling transmission path of a work vehicle, the drum member 140 is positioned at the parking position P while the work vehicle is located on a slope. Assume that the drum-type transmission 1A is in the parking stage engaged state.

  In such a situation, gravity applied to the work vehicle is reversely transmitted from the driving wheel to the first transmission rotating shaft 810, and a rotational driving force around the axis acts on the first transmission rotating shaft 810.

  In general, the concave section of the concave / convex engaging structure (in this embodiment, the concave section of the parking concave / convex section 112P) is formed in a tapered shape that becomes narrower as it goes radially inward. By making the cross-sectional view shape of the convex portion to be engaged (engagement portion 515 of the parking operation arm 510 in the present embodiment) a taper shape corresponding to the concave portion, it is possible to make the concave-convex engagement easy. Can be secured.

  On the other hand, if the concave and convex portions of the parking uneven portion 112P and the engaging portion 515 are tapered, the reverse driving force from the driving wheel is transmitted to the first transmission rotating shaft 810. This reverse driving force acts as a force for swinging the parking operation arm 510 in the parking release direction, and the parking operation arm 510 located at the parking position is unexpectedly moved in the parking release direction. As a result of swinging, the concave / convex engagement of the parking operating arm 510 and the parking concave / convex portion 112P may be released.

  In this regard, if the “replacement” configuration by the cam pushing portion 535 is provided, it is possible to effectively prevent or reduce the situation in which the parking operation arm 510 swings unexpectedly from the parking position in the release direction.

  Further, in the present embodiment, as shown in FIGS. 14 and 15, etc., the cam pushing portion 535 is not engaged with the parking operation arm 510, that is, the drum member 140 is at a low speed position. In the state where the fork shaft 120 is positioned at the operation position from L to the reverse position R, the fork shaft 120 is applied to the parking operation arm 510 urged in the parking release direction around the swing axis 505 by the parking release spring 520. It is configured to abut and define a swing end of the parking operation arm 510 in the parking release direction.

  With such a configuration, the parking release direction is set by the parking release spring 520 in a situation where the drum member 140 is positioned at the operation position between the low speed position L and the reverse drive position R without providing an additional member. The parking operating arm 510 biased toward the parking force is pressed against the parking pushing member 530, and the biasing force of the parking release spring 520 affects the operation of the drum member 140 around the axis. It can be effectively prevented.

The parking push member 530 supported by the drum member 140 and the swing axis 505 parallel to the first transmission rotation shaft 810 can swing, and the engaging portion 515 is provided at a free end. The parking operation arm 510 and a parking release spring 520 that urges the parking operation arm 510 in the release direction around the swing axis 505 are provided, and the rotation of the drum member 140 at the parking position P is utilized. The lock mechanism 500 that causes the parking operation arm 510 to swing by the parking push member 530 to reveal the parking stage engagement state is parked on the shifter member (the second shifter member 110 (2)). The present invention is not applied only to the form in which the uneven portion 112P is provided. The shifter member (the second shifter member 110 (2)) is applicable to form a dedicated parking gear 10P of another member.
FIG. 20 is a cross-sectional view of a modified example in which the lock mechanism 500 is applied to a form provided with a parking gear 10P that is a member different from the shifter member (the second shifter member 110 (2)).

Embodiment 2
Hereinafter, other embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 21 is a cross-sectional view of the drum-type transmission 1B according to the present embodiment, and shows a cross-sectional view corresponding to FIG. 4 of the first embodiment.
In the figure, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

  The drum-type transmission 1B according to the present embodiment is different from the drum-type transmission 1A according to the first embodiment in that a drum-type transmission operation mechanism 100B is provided instead of the drum-type transmission operation mechanism 100A. doing.

  As shown in FIG. 21, the drum-type speed change operation mechanism 100B includes the first shifter member 110 (1), the second shifter member 110B (2), the fork shaft 120, the first shift fork 130 ( 1), the second shift fork 130 (2), and a drum member 140B.

  The first shifter member 110 (1) is supported on the first transmission rotating shaft 810 between the transmission gear 10H and the transmission gear 10R so as not to rotate relative to the first transmission rotating shaft 810 and to move in the axial direction. It is moved in the axial direction by 1).

  The first shifter member 110 (1) has a high-speed concavo-convex portion 112H that can be concavo-convexly engaged with the transmission concavo-convex portion 12H of the transmission gear 10H on one end face in the axial direction facing the transmission gear 10H, A reverse concavo-convex portion 112R that can engage with the concavo-convex portion for shifting 12R of the transmission gear 10R on the other end surface in the axial direction opposite to the transmission gear 10R is provided.

  The first shifter member 110 (1) and the first shift fork 130 (1) have a reference in which the first shifter member 110 (1) does not engage with either the transmission gear 10H or the transmission gear 10R in the axial direction. 21 (see FIG. 21), a high speed position at which the first shifter member 110 (1) engages with the transmission gear 10H, and a reverse position at which the first shifter member 110 (1) engages with the transmission gear 10R. And can take.

  The drum-type transmission 1B according to the present embodiment includes, as the transmission gear 10, a parking gear (transmission gear 10P) that forms a parking stage in addition to the transmission gear 10H, the transmission gear 10L, and the transmission gear 10R. Yes.

The parking gear (transmission gear 10P) is fixed to a fixing member such as the transmission case 805 so as not to rotate.
That is, in the present embodiment, the parking gear (transmission gear 10P) is a separate member from the shifter member.

  In such a configuration, the second shifter member 110B (2) is supported between the transmission gear 10L and the transmission gear 10P so as to be non-rotatable relative to the first transmission rotation shaft 810 and movable in the axial direction. It is moved in the axial direction by the two-shift fork 130 (2).

  The second shifter member 110B (2) has a low-speed concavo-convex portion 112L that can be concavo-convexly engaged with the shift concavo-convex portion 12L of the transmission gear 10L on the end surface on one side in the axial direction facing the transmission gear 10L, and A parking uneven portion 112P that can engage with the shift uneven portion 12P of the transmission gear 10P on the other end face in the axial direction facing the transmission gear 10P is provided.

  The second shifter member 110B (2) and the second shift fork 130 (2) have a reference in which the second shifter member 110B (2) does not engage with either the transmission gear 10L or the transmission gear 10P in the axial direction. 21 (see FIG. 21), a low speed position where the second shifter member 110B (2) engages with the transmission gear 10L, and a parking position where the second shifter member 110B (2) engages with the transmission gear 10P. And can take.

  As shown in FIG. 21, the drum-type speed change operation mechanism 100B further includes a first shift fork that pushes the first boss portion 132 (1) of the first shift fork 130 (1) to the second side in the axial direction. A push spring 160 (1), a second shift fork push spring 160 (2) that pushes the second boss 132 (2) of the second shift fork 130 (2) toward the first axial side, The first boss portion 132 (1) is axially moved to the first boss portion 132 (1) in a state where a moving end toward the first axial direction is defined by the first stop portion 133 (1) provided on the first boss portion 132 (1). A moving end toward the second axial direction is defined by the first slider member 170 (1) supported in a possible manner and the second stop portion 133 (2) provided in the second boss portion 132 (2). Can move axially to the second boss 132 (2) in a state A supported second slider member 170 (2), a first slider member pushing spring 180 (1) for pushing the first slider member 170 (1) to the first axial direction, and the second slider member And a second slider member pushing spring 180 (2) that pushes 170 (2) to the second side in the axial direction.

The axial position of the first slider member 170 (1) is regulated by a first slider guide groove 144B (1) provided in the drum member 140B.
That is, the first slider member 170 (1) includes a first slider body 172 (1) externally inserted in the first boss portion 132 (1) so as to be movable in the axial direction, and a first slider of the drum member 140B. And a first slider engaging pin portion 174 (1) engaged with the guide groove 144B.

The axial position of the second slider member 170 (2) is regulated by a second slider guide groove 144B (2) provided in the drum member 140B.
That is, the second slider member 170 (2) includes a second slider body 172 (2) externally inserted in the second boss portion 132 (2) so as to be movable in the axial direction, and a second slider of the drum member 140B. And a second slider engaging pin portion 174 (2) engaged with the guide groove 144B (2).

The first slider member pushing spring 180 (1) has a larger urging force than the first shift fork pushing spring 160 (1).
The second slider member pushing spring 180 (2) has a larger urging force than the second shift fork pushing spring 160 (2).

  As shown in FIG. 21, in the present embodiment, the first and second slider member pushing springs 180 (1) and 180 (2) are engaged with the first slider member 170 (1) at one end side. And the other end is formed by a single spring 210 engaged with the second slider member 170 (2).

Here, the guide groove formed in the drum member 140B will be described.
FIG. 22 is a development view of the drum member 140B.

  As shown in FIG. 22, the drum member 140B has a first fork guide groove 142B (1) into which the first engagement pin portion 134 (1) of the first shift fork 130 (1) is engaged, The second fork guide groove 142B (2) in which the second engagement portion 134 (2) of the second shift fork 130 (2) is engaged, and the first slider engagement of the first slider member 170 (1). The first slider guide groove 144B (1) in which the pin portion 174 (1) is engaged and the second slider engaging pin portion 171 (2) of the second slider member 170 (2) are engaged. A slider guide groove 144B (2) is provided.

First, the groove shape of the first fork guide groove 142B (1) will be described.
As shown in FIG. 22, the neutral engagement portion 142B (1) N of the first fork guide groove 142B (1) is fixed to the first engagement so as to fix the first shift fork 130 (1) to a reference position. It has a groove shape that holds the mating pin portion 134 (1).

  In the high speed engagement portion 142B (1) H, the moving end of the first shift fork 130 (1) in the first axial direction is the high speed position, and the moving end of the first shift fork 130 (1) in the second axial direction is the reference position. Further, it has a groove shape for guiding the first engagement pin 134 (1).

  The transition portion located between the neutral engagement portion 142B (1) N and the high speed engagement portion 142B (1) H is a movement end of the first shift fork 130 (1) toward the second side in the axial direction. The movement end of the first shift fork 130 (1) in the first axial direction is changed from the reference position to the high speed position according to the rotation from the neutral position N to the high speed position H of the drum member 140B while being fixed at the reference position. It has such a groove shape.

  The low speed engagement portion 142B (1) L has a groove shape that holds the first engagement pin portion 134 (1) so as to fix the first shift fork 130 (1) at a reference position. Yes.

  The transition portion between the high-speed engagement portion 142B (1) H and the low-speed engagement portion 142B (1) L has a movement end of the first shift fork 130 (1) in the second axial direction as a reference position. As the drum member 140B (1) rotates from the high speed position H to the low speed position N, the moving end of the first shift fork 130 (1) changes from the high speed position to the reference position. It has a groove shape.

  The reverse engagement portion 142B (1) R is such that the moving end of the first shift fork 130 (1) toward the first axial direction is the reference position and the moving end toward the second axial direction is the reverse position. Further, it has a groove shape for guiding the first engagement pin 134 (1).

  The transition portion located between the neutral engagement portion 142B (1) N and the reverse engagement portion 142B (1) R is a movement end of the first shift fork 130 (1) toward the first side in the axial direction. While being fixed at the reference position, the moving end of the first shift fork 130 (1) in the second axial direction is changed from the reference position to the reverse position according to the rotation from the neutral position N to the reverse position R of the drum member 140B. It has such a groove shape.

  The parking engagement portion 142B (1) P has a groove shape that holds the first engagement pin portion 134 (1) so as to fix the first shift fork 130 (1) to a reference position. Yes.

  The transition portion between the reverse-engagement portion 142B (1) R and the parking-time engagement portion 142B (1) P is the reference position of the moving end of the first shift fork 130 (1) toward the first side in the axial direction. The moving end of the first shift fork 130 (1) in the second axial direction is changed from the reverse position to the reference position according to the rotation from the reverse position R to the parking position P of the drum member 140B. It has a groove shape.

Next, the groove shape of the first slider guide groove 144B (1) will be described.
The high-speed engagement portion 144B (1) H of the first slider guide groove 144B (1) is such that the first slider member 170 (1) presses the first shift fork 130 (1) toward the first side in the axial direction. In this state, the first shifter fork 130 (1) can move in the axial direction between the reference position restricted by the first fork guide groove 142B (1) and the first speed change position. 1) shows the movable range in the axial direction.

  Specifically, the first shift fork 130 (1) is positioned at the reference position, the high speed position, and the reverse position while the first slider member 170 (1) is in contact with the first stop portion 133 (1). In this case, the axial position where the first slider member 170 (1) is positioned is defined as a reference position, a first displacement position, and a second displacement position, respectively.

  In the present embodiment, as shown in FIG. 22, the high-speed engagement portion 144B (1) H of the first slider guide groove 144B (1) The first slider member 170 (1) is guided so as to be movable between the first displacement positions.

  The reverse engagement portion 144B (1) R is permitted by the reverse shift engagement portion 142B (1) R of the first shift fork guide groove 142B (1) when the drum member 140B is positioned at the reverse position R. The first slider member 170 (1) is fixed at a retracted position that does not limit the axial movement range of the first shift fork 130 (1).

  In the present embodiment, as shown in FIG. 22, the reverse slider engagement portion 144B (1) R of the first slider guide groove 144B (1) displaces the first slider member 170 (1) to the second displacement. It is configured to be fixed in position.

  That is, in the present embodiment, the first slider guide groove 144B (1) has the first slider member 170 (1) as the retracted position when the drum member 140B is positioned at the high speed position. It is comprised so that it may fix to two displacement positions.

In the present embodiment, the slider guide groove 144B (1) further has the following groove shape.
That is, as shown in FIG. 22, the neutral engagement portion 144B (1) N pushes the first slider engagement pin portion 174 (1) so as to fix the first slider member 170 (1) at the reference position. It has a groove shape to pinch.

  The transition portion between the neutral engagement portion 144B (1) N and the high speed engagement portion 144B (1) H is a reference position of the moving end of the first slider member 170 (1) toward the second side in the axial direction. The movement end of the first slider member 170 (1) in the first axial direction changes from the reference position to the first displacement position according to the rotation from the neutral position N to the high speed position H of the drum member 140B. It has a groove shape.

  The low speed engagement portion 144B (1) L has a groove shape that holds the first slider engagement pin portion 174 (1) so as to fix the first slider member 170 (1) at a reference position. Yes.

  The transition portion between the high-speed engagement portion 144B (1) H and the low-speed engagement portion 144B (1) L is the reference position of the moving end of the first slider member 170 (1) toward the second side in the axial direction. The movement end of the first slider member 170 (1) in the first axial direction is fixed from the first displacement position to the reference position in accordance with the rotation of the drum part 140B from the high speed position H to the low speed position L. It has a groove shape that can be changed.

  A transition portion between the neutral engagement portion 144B (1) N and the reverse engagement portion 144B (1) R is the first slider member 170 according to the rotation from the neutral position N to the reverse position R of the drum member 140B. It has a groove shape that guides (1) from the reference position to the second displacement position.

  The parking engaging portion 144B (1) P has a groove shape that holds the slider engaging pin portion 174 (1) so as to fix the first slider member 170 (1) at a reference position.

  The transition portion between the reverse engagement portion 144B (1) N and the parking engagement portion 144 (1) P is the first slider member 170 according to the rotation from the reverse position R to the parking position P of the drum member 140B. It has a groove shape that guides (1) from the second displacement position to the reference position.

Next, the groove shape of the second fork guide groove 142B (2) will be described.
The second fork guide groove 142B (2) is configured such that when the drum member 140B is positioned at the low speed position L, the second shift fork 130 (2) moves in the axial direction between the reference position and the low speed position. When the drum member 140B is positioned at the parking position P, the second shift fork 130 (2) is allowed to move in the axial direction between the reference position and the parking position, while the drum When the member 140B is positioned at the other operation position, it has a groove shape that fixes the second shift fork 130 (2) at the reference position.

  That is, as shown in FIG. 22, in the region from the high speed engagement portion 142B (2) H to the reverse travel engagement portion 142B (2) R, the second shift fork 130 (2) is fixed at the reference position. Thus, it has a groove shape that holds the second engagement pin portion 134 (2).

  On the other hand, in the low speed engagement portion 142B (2) L, the moving end of the second shift fork 130 (2) toward the first axial direction is the low speed position, and the moving end toward the second axial direction is the reference position. Thus, the groove has a groove shape for guiding the second engagement pin portion 134 (2).

  The transition portion between the high-speed engagement portion 142B (2) H and the low-speed engagement portion 142B (2) L is the movement end of the second shift fork 130 (2) toward the second side in the axial direction. While being fixed at the reference position, the moving end of the second shift fork 130 (2) in the first axial direction is changed from the reference position to the low speed position according to the rotation of the drum member 140B from the high speed position H to the low speed position L. It has such a groove shape.

  In the parking engagement portion 142B (2) P, the moving end of the second shift fork 130 (2) toward the first side in the axial direction becomes the reference position, and the moving end toward the second side in the axial direction becomes the parking position. Thus, it has a groove shape for guiding the second engagement pin portion 134 (2).

  A transition portion between the reverse engagement portion 142B (2) R and the parking engagement portion 142B (2) P is a movement end of the second shift fork 130 (2) toward the first side in the axial direction. While being fixed at the reference position, the moving end of the second shift fork 130 (2) in the second axial direction is changed from the reference position to the parking position according to the rotation of the drum member 140B from the reverse position R to the parking position P. It has such a groove shape.

Next, the groove shape of the second slider guide groove 144B (2) will be described.
The low-speed engagement portion 144B (2) L of the second slider guide groove 144B (2) has a low speed of the second shift fork guide groove 142B (2) when the drum member 140B is positioned at the low speed position L. The second slider member 170 (2) is fixed at a retracted position that does not limit the axial movement range of the second shift fork 130 (2) permitted by the hour engagement portion 142B (2) L.

  Specifically, the second shift fork 130 (2) is positioned at the reference position, the low speed position, and the parking position while the second slider member 170 (2) is kept in contact with the second stop portion 133 (2). In this case, the axial position where the second slider member 170 (2) is positioned is defined as a reference position, a third displacement position, and a fourth displacement position, respectively.

  In the present embodiment, as shown in FIG. 22, the low-speed engaging portion 144B (2) L of the second slider guide groove 144B (2) displaces the second slider member 170 (2) in the third displacement. It is configured to be fixed in position.

  That is, in the present embodiment, the second slider guide groove 144B (2) has the second slider member 170 (2) as the retracted position when the drum member 140B is positioned at the low speed position L. It is comprised so that it may fix to a 3rd displacement position.

  In the parking engagement portion 144B (2) P of the second slider guide groove 144B (2), the second slider member 170 (2) presses the second shift fork 130 (2) to the second side in the axial direction. In such a state, the second slider member 170 (2) is moved so that the second shift fork 130 (2) can move between the reference position and the parking position regulated by the second fork guide groove 142B (2). Describes the axially movable range.

  In the present embodiment, as shown in FIG. 22, the parking slider engaging portion 144B (2) P of the second slider guide groove 144B (2) has the second slider member 170 (2) at the reference position and the first position. The second slider member 170 (2) is guided so as to be movable between the four displacement positions.

  The drum-type transmission 1B having such a configuration can exhibit a standby action in a shifting operation.

First, the standby operation in the shifting operation to the high speed stage will be described.
When the drum member 140B is positioned at the neutral position N, as described above, the first shift fork 130 (1) and the second shift fork 130 (2) are fixed at the reference position ( (See FIG. 22).
Accordingly, the first and second shifter members 110 (1) and 110B (1) are both positioned at the reference position, and the drum-type transmission 1B is in a neutral state (see FIG. 21).

  When the drum member 140B is operated from the neutral position N to the high speed position H, as described above, the axial direction of the first shift fork 130 (1) regulated by the first fork guide groove 142B (1). The moving end on the first side changes from the reference position to the high speed position according to the rotation from the neutral position N to the high speed position H of the drum member 140B. The shift fork 130 (1) is movable in the axial direction between the reference position and the high speed position.

  As described above, the first slider member pushing spring 180 (1) (in this embodiment, the single spring 210) for biasing the first slider member 170 (1) toward the first axial direction is attached. Since the urging force is greater than the urging force of the first shift fork pushing spring 160 (1) that urges the first shift fork 130 (1) in the second axial direction, the drum member 140B When positioned at the high speed position H, the first shift fork 130 (1) and the first shifter member 170 (1) are moved from the first slider member pushing spring 180 (1) and the first shift fork. It will be in the state which can be moved to the high speed position of the axial direction 1st side with the urging | biasing force of the magnitude | size according to the difference of the urging | biasing force of the pushing spring 160 (1).

  Here, when the drum member 140B is positioned at the high speed position H, the relative position around the axis between the high speed uneven portion 112H of the first shifter member 110 (1) and the speed change uneven portion 12H of the transmission gear 10H. Is in a position where it can be engaged with unevenness, the unevenness portion for high speed 112H and the unevenness portion for shifting 12H are immediately engaged with unevenness and the transmission gear 10H is in a transmission state, so that the drum-type transmission 1B immediately becomes high speed. A step engagement state is established.

  On the other hand, when the convex part of the uneven part for high speed 112H of the first shifter member 110 (1) and the convex part of the uneven part for shifting 12H of the transmission gear 10H are brought into contact with each other, Only the drum member 140B can be rotated in advance to the high speed position H while the first shift fork 130 (1) and the first shifter member 110 (1) remain in the reference position.

  In the state in which the drum member 140B is rotated to the high speed position H, the first shift fork 130 (1) is axially movable between the reference position and the high speed position, and the first slider member 110 (1 ) Is movable in the axial direction between the reference position and the first displacement position.

  Accordingly, when the first shifter member 110 (1) and the transmission gear 10H rotate relative to each other around the axis and the butting of the convex portions is resolved, the first slider member pushing spring 180 (1) (main) In an embodiment, the single spring 210) and the first shift fork push spring 160 (1) are biased through the first shift fork 130 (1) by a biasing force having a magnitude corresponding to a difference in biasing force. The first shifter member 110 (1) is pushed to the high speed position and engages with the transmission gear 10H so that the shift operation to the high speed stage of the drum type transmission 1B is completed (standby action to the high speed stage). ).

  When the drum member 140B is positioned at the high speed position H, as described above, the second shift fork 130 (2) and the second shifter member 110B (2) are fixed at the reference position, The second shifter member 110B (2) is in a state in which neither the transmission gear 10L nor the transmission gear 10P is engaged with the concave and convex portions.

Next, the standby action in the shifting operation to the low speed stage will be described.
When the drum member 140B is positioned at the low speed position L, the first shift fork 130 (1) is fixed at the reference position, and the first shifter member 110 (1) is connected to both the high speed gear 10H and the reverse gear 10R. It will be in the state which does not engage with unevenness.

  On the other hand, the second shift fork 110 (2) is axially movable between the reference position and the low speed position, and the second slider member 110B (2) is in the retracted position (in this embodiment). The third displacement position is fixed.

  In this state, the urging force of the second slider member pushing spring 180 (2) does not act on the second shift fork 110 (2), and the second shift fork 110 (2) has the second force on the second shift fork 110 (2). Only the biasing force toward the second axial direction by the shift fork pushing spring 160 (2) acts.

  Accordingly, when the drum member 140B is positioned at the low speed position L, the second shift fork 130 (2) and the second shifter member 110B (2) are moved at a low speed by the second shift fork pushing spring 160 (2). It will be in the state which can be moved to a position.

  Here, when the drum member 140B is positioned at the low speed position L, the relative position around the axis between the low speed uneven portion 112L of the second shifter member 110B (2) and the speed change uneven portion 12L of the transmission gear 10L. , The low-speed concavo-convex portion 112L and the shift concavo-convex portion 12L immediately engage with the concavo-convex portion, and the transmission gear 10L enters the transmission state, so that the drum-type transmission 1B immediately becomes low-speed. A step engagement state is established.

  On the other hand, when the convex part of the uneven part for low speed and high speed 112L of the second shifter member 110B (2) and the convex part of the uneven part for shifting 12L of the transmission gear 10L are brought into contact with each other, While the second shift fork 130 (2) and the second shifter member 110B (2) are held at the reference position, only the drum member 140B is advanced to the low speed position L.

  Accordingly, when the second shifter member 110B (2) and the transmission gear 10L are relatively rotated about the axis and the abutment between the convex portions is eliminated, the second shift fork pushing spring 160 (2) is attached. The second shifter member 110B (2) is pushed to the low speed position by the force and engages with the transmission gear 10L so that the gear shift operation to the low speed stage of the drum type transmission 1B is completed (to the low speed stage). Standby action).

Next, the standby operation in the shifting operation to the reverse gear will be described.
When the drum member 140B is positioned at the reverse drive position R, the second shift fork 130 (2) is fixed at the reference position, and the second shifter member 110B (2) is connected to both the transmission gear 10L and the transmission gear 10P. It will be in the state which does not engage with unevenness.

  On the other hand, the first shift fork 130 (1) is in an axially movable state between a reference position and a reverse position, and the first slider member 110 (1) is in a retracted position (in the present embodiment, a first position). 2 displacement position).

  In this state, the biasing force of the first slider member pushing spring 180 (1) does not act on the first shift fork 130 (1), and the first shift fork 130 (1) has the first force. Only the biasing force toward the second axial direction by the shift fork pushing spring 160 (1) acts.

  Accordingly, when the drum member 140B is positioned at the reverse position R, the first shift fork 130 (1) and the first shifter member 110 (1) are moved backward by the first shift fork pushing spring 160 (1). It will be in the state which can be moved to a position.

  Here, when the drum member 140B is positioned at the reverse position R, the relative position around the axis between the reverse uneven portion 112R of the first shifter member 110 (1) and the shift uneven portion 12R of the transmission gear 10R. Is the position where the concave and convex portions can be engaged with each other, the reverse concave and convex portions 112R and the shift concave and convex portions 12R immediately engage with the concave and convex portions, and the transmission gear 10R is brought into a transmission state, so that the drum-type transmission 1B immediately reverses. A step engagement state is established.

  On the other hand, when the convex part of the reverse uneven part 112R of the first shifter member 110 (1) and the convex part of the convex part 12R for shifting of the transmission gear 10R are brought into contact with each other, While the first shift fork 130 (1) and the first shifter member 110 (1) are held at the reference position, only the drum member 140B is rotated forward to the reverse position R.

  Then, when the first shifter member 110 (1) and the transmission gear 10R rotate relative to each other about the axis and the abutment between the convex portions is eliminated, the first shift fork pushing spring 160 (1) is attached. The first shifter member 110 (1) is pushed to the reverse position by the force and engages with the transmission gear 10R, and the shift operation to the reverse speed of the drum type transmission 1B is completed (to the reverse speed). Standby action).

Finally, the standby action in the shifting operation to the parking stage will be described.
When the drum member 140B is positioned at the parking position P, the first shift fork 130 (1) is fixed at the reference position, and the first shifter member 110 (1) is connected to both the transmission gear 10H and the transmission gear 10R. It will be in the state which does not engage with unevenness.

  Meanwhile, the second shift fork 130 (2) is axially movable between the reference position and the parking position, and the second slider member 110B (2) is axially moved between the reference position and the fourth displacement position. The direction is movable.

  As described above, the second slider member pushing spring 180 (2) (in the present embodiment, the single spring 210) for biasing the second slider member 110B (2) toward the second axial direction is attached. Since the urging force is greater than the urging force of the second shift fork pushing spring 160 (2) that urges the second shift fork 130 (2) toward the first axial direction, the drum member 140B When positioned at the parking position P, the second shift fork 130 (2) and the second shifter member 110B (2) are moved to the second slider member pushing spring 180 (2) and the second shift fork. It becomes a state where it can be moved to the parking position on the second axial side with an urging force having a magnitude corresponding to the difference in the urging force of the push spring 160 (2).

  Here, when the drum member 140B is positioned at the parking position P, the relative position around the axis between the parking uneven portion 112P of the second shifter member 110B (2) and the shifting uneven portion 12P of the transmission gear 10P. , The parking uneven portion 112P and the shifting uneven portion 12P immediately engage with the concave and convex portions, and the drum type transmission 1B immediately enters the parking stage engaged state.

  On the other hand, when the convex part of the parking uneven part 112P of the second shifter member 110B (2) and the convex part of the shifting uneven part 12P of the transmission gear 10P are brought into contact with each other, Only the drum member 140B is advanced to the parking position P while the second shift fork 130 (2) and the second shifter member 110B (2) remain in the reference position.

  Then, when the second shifter member 110B (2) and the transmission gear 10P rotate relative to each other around the axis and the butting of the convex portions is eliminated, the second slider member pushing spring 180 (2) and the The second shifter member 110B (2) is pushed to the parking position by the biasing force having a magnitude corresponding to the difference in the biasing force of the second shift fork pushing spring 160 (2), and is engaged with the transmission gear 10P. Then, the shifting operation to the parking stage of the drum type transmission 1B is completed (standby operation to the parking stage).

  Thus, the drum-type transmission 1B according to the present embodiment can also have a standby action for all the gears including the parking gear.

  Further, the first boss portion 132 (1) of the first shift fork 130 (1) and the first boss portion 132 (2) of the second shift fork 130 (2) are movably supported. And the second slider members 170 (1) and 170 (2) and the first and second shift forks 130 (1) and 130 (2) are moved in the axial direction to bring out a standby action. Yes.

  Accordingly, the axial direction can be reduced in size and the operating force can be reduced as compared with the conventional configuration configured to obtain a standby action by moving the fork shaft in the axial direction.

  In the present embodiment, the first slider guide groove 144B (1) fixes the first slider member 110 (1) to a reference position when the drum member 140B is positioned at the neutral position N. When the drum member 140B is positioned at the high speed position H, the first slider member 110 (1) can be moved in the axial direction between the reference position and the first displacement position, and the drum member 140B is moved at the low speed position. The first slider member 110 (1) is fixed at a reference position when positioned at L, and the first slider member 110 (1) is fixed when the drum member 140B is positioned at a reverse position R. The first slider member 110 (1) is fixed at a reference position when the drum member 140B is positioned at the parking position P. The present invention is not limited to this aspect.

  For example, when the drum member 140B is positioned at the reverse position R, the first slider member 110 (1) is fixed at the retracted position (for example, the second displacement position), while the drum member 140B (1) is fixed. When positioned at a position other than the reverse position R, the first slider member 170 (1) biased toward the first axial direction by the first slider member pushing spring 180 (1) is the first slider member 170 (1). The first slider guide formed to allow the first shift fork 130 (1) to move in the axial direction following the movement in the axial direction while remaining in contact with the stop portion 133 (1). It is also possible to employ the groove 145B (1).

FIG. 23 is a development view of the drum member 140B including the first slider guide groove 145B (1).
As shown in FIG. 23, the reverse slider engagement portion 145B (1) R of the first slider guide groove 145B (1) fixes the first slider member 170 (1) to a retracted position (for example, a second displacement position). In addition, the neutral engagement portion 145B (1) N, the high speed engagement portion 145B (1) H, the low speed engagement portion 145B (1) L, and the parking engagement portion 145B (1) P One slider member 110 (1) has a groove shape that allows the slider member 110 (1) to move in the axial direction between the first displacement position and the second displacement position.

Further, the second slider guide groove 144B (2) is not limited to the groove shape in the present embodiment.
That is, in the present embodiment, the second slider guide groove 144B (2) is configured such that the second slider member 110B is located when the drum member 140B is positioned at the neutral position N, the high speed position H, and the reverse position R. (2) is fixed at the reference position, and when the drum member 140B is positioned at the low speed position L, the second slider member 110B (2) is fixed at the third displacement position, and the drum member 140B is positioned at the parking position. When positioned at P, the second slider member 110B (2) is configured to be axially movable between the reference position and the fourth displacement position.

  Instead, when the drum member 140B is positioned at the low speed position L, the second slider member 110B (2) is fixed at the retracted position (for example, the third displacement position), while the drum member 140B is fixed. When positioned at a position other than the low speed position L, the second slider member 170 (2) biased toward the second axial direction by the second slider member pushing spring 180 (2) is The second slider guide formed to allow the second shift fork 130 (2) to move in the axial direction following the movement in the axial direction while being in contact with the stop portion 133 (2). It is also possible to employ the groove 145B (2).

FIG. 23 shows the second slider guide groove 145B (2).
As shown in FIG. 23, the low-speed engagement portion 145B (2) of the second slider guide groove 145B (2) fixes the second slider member 110B (2) to a retracted position (for example, a third displacement position). Further, the other neutral engagement portion 145B (2) N, the high speed engagement portion 145B (2) H, the reverse engagement portion 145B (2) R, and the parking engagement portion 145B (2) P are the second ones. The slider member 110B (2) has a groove shape that allows the slider member 110B (2) to move in the axial direction between the third displacement position and the fourth displacement position.

1A, 1B Drum-type transmission 10H High-speed gear (first transmission member)
10R Reverse gear (second speed change member)
10L Low speed gear (3rd speed change member)
10P Parking gear (4th speed change member)
100A, 100B Drum-type speed change operation mechanism 110 (1) First shifter member 110 (2), 110B (2) Second shifter member 112P Parking uneven portion 120 Fork shaft 130 (1) First shift fork 130 (2) First 2 shift fork 132 (1) 1st boss part 132 (2) 2nd boss part 133 Stop part 133 (1) 1st stop part 133 (2) 2nd stop part 134 (1) 1st engagement pin part 134 ( 2) Second engaging pin portion 136 (1) First fork portion 136 (2) Second fork portion 140, 140B Drum members 142 (1), 142B (1) First fork guide grooves 142 (2), 142B ( 2) Second fork guide grooves 144, 145 Slider guide grooves 144B (1), 145B (1) First slider guide grooves 144B (2), 145B (2) Second slur Idder guide groove 160 (1) First shift fork pushing spring 160 (2) Second shift fork pushing spring 170 Slider member 170 (1) First slider member 170 (2) Second slider member 180 Slider member pushing spring 180 (1) First slider member pushing spring 180 (2) Second slider member pushing spring 210 Single spring 505 Oscillating axis 510 Parking operating arm 515 Engaging portion 520 Parking release spring 530 Parking pushing member 532 Body 535 Cam pusher 540 Coil spring 810 for parking First transmission rotary shaft (shift output shaft)
820 Second transmission rotating shaft (speed change input shaft)

Claims (12)

Between the first and second speed change members that are rotatably supported by the transmission rotation shaft, the transmission rotation shaft is supported so as not to be relatively rotatable and to be movable in the axial direction, and the first side and the other side of the one side in the axial direction are supported. A first shifter member for engaging and disengaging the first and second speed change members according to the movement toward the second side to bring the first and second speed change members into a power transmission state; and a first fork guide groove A drum member that is rotated around an axis, a fork shaft that is arranged in parallel to the transmission rotation shaft, a first boss portion that is supported by the fork shaft so as to be movable in the axial direction, and the first fork A drum-type speed change operation mechanism comprising a first shift pin having a first engagement pin portion engaged with a guide groove and a first fork portion engaged with the first shifter member,
A first shift fork pushing spring for urging the first boss portion toward the first axial direction;
A slider guide provided on the drum member, supported by the first boss portion so as to be movable in the axial direction in a state where a moving end toward the second axial direction is defined by a stop portion provided on the first boss portion. A slider member whose axial position is regulated by a groove;
A slider member pushing spring that urges the slider member toward the second axial direction with a larger urging force than the first shift fork pushing spring;
The first shift fork and the first shifter member are related to an axial position, the reference position where the first shifter member does not engage with any of the first and second transmission members, and the first shifter member The first and second speed change positions that engage with the first and second speed change members respectively can be selectively taken.
The first fork guide groove fixes the first shift fork to a reference position when the drum member is positioned at the neutral position around the axis, and the first fork guide groove is located at one side around the axis from the neutral position. The first shift fork is allowed to move between the reference position and the first shift position, and the drum member is positioned at the second operation position on the other side around the axis from the neutral position. Has a groove shape that allows the first shift fork to move between the reference position and the second shift position,
The slider guide groove guides the slider member so as not to obstruct movement between the reference position of the first shift fork and the first shift position when the drum member is positioned at the first shift position, When the drum member is positioned at the second speed change position, the slider member biased by the slider member pressing spring can push the first shift fork from the reference position to the second speed change position. A drum-type speed change operation mechanism characterized by having a groove shape that allows the slider member to move in the axial direction.   When the first shift fork is positioned at the reference position, the first shift position and the second shift position, the axial position where the slider member is in contact with the stop portion is positioned as the reference position and the first shift position, respectively. In the case of the displacement position and the second displacement position, the slider guide groove fixes the slider member at a reference position when the drum member is positioned at the neutral position, and the drum member is at the first operation position. When the slider member is positioned, the slider member is fixed at the first displacement position, and when the drum member is positioned at the second operation position, the slider member moves between the reference position and the second displacement position. The drum-type speed change operation mechanism according to claim 1, wherein the drum-type speed change operation mechanism has a groove shape that allows   The slider guide groove is configured such that when the drum member is positioned at a position other than the first speed change position, the slider member that is urged toward the second axial direction by the slider member pushing spring is moved to the stop portion. 2. The drum type according to claim 1, wherein the drum type has a groove shape that allows the first shift fork to move in the axial direction while following the movement of the first shift fork in the axial direction. Shifting operation mechanism. A second shifter member that is supported on the transmission rotation shaft so as not to rotate relative to the transmission shaft and that can move in the axial direction, and is moved in the axial direction toward a third speed change member that is supported so as to be relatively rotatable on the transmission rotation shaft. A second shifter member capable of engaging with the third transmission member in a concavo-convex manner,
The second boss portion supported by the fork shaft so as to be movable in the axial direction, the second engagement pin portion engaged in the second fork guide groove provided in the drum member, and the second shifter member are engaged. A second shift fork having a second fork portion;
A second shift fork pushing spring for urging the second boss portion in a direction in which the second shifter member is pushed toward the third speed change member;
The second shift fork and the second shifter member are axial positions, the second shifter member is not engaged with the third transmission member, and the second shifter member is uneven with the third transmission member. The third shift position to be engaged can be taken,
The first fork guide groove fixes the first shift fork at a reference position when the drum member is positioned at a neutral position and at a third operation position that is displaced about the axis from the first and second operation positions. Has a groove shape,
The second fork guide groove allows the second shift fork to move between a reference position and a third shift position when the drum member is positioned at the third operation position, and the drum member is The drum type according to any one of claims 1 to 3, wherein the drum type has a groove shape for fixing the second shift fork at a reference position when it is located at an operation position other than the three operation positions. Shifting operation mechanism.   5. The drum-type speed change operation mechanism according to claim 4, wherein the drum member is located at a third operation position when rotated by a predetermined angle from the first operation position to one side around the axis. A parking push member having a main body portion that is extrapolated to the drum member so as to be relatively rotatable, and a cam push portion that extends radially outward from the main body portion;
A coil spring for parking which is externally connected to the drum member in a state where one end side is operatively connected to the parking push member and the other end side is operatively connected to the drum member, and is a circumferential direction applied to the cam push portion When the load is equal to or less than a predetermined value, the parking push member is connected so as not to be relatively rotatable so that the parking push member integrally rotates about the axis along with the rotation of the drum member about the axis. A parking coil spring that elastically deforms when the circumferential load applied to the pushing portion exceeds a predetermined value, and allows the drum member to make a preceding relative rotation around the axis with respect to the parking pushing member;
An operating arm for parking which is swingable about a swing axis parallel to the transmission rotation shaft and is provided with an engagement portion on a free end side, wherein the engagement portion is arranged around the swing axis. An operating arm for parking which can take a parking position that engages with a concavo-convex portion provided so as to face the radially outward direction of the 2 shifter member and forcibly stops the rotation of the second shifter member;
A parking release spring that biases the operating arm for parking around the swing axis in a direction in which the engaging portion is separated from the uneven portion;
The cam pusher is arranged to swing the parking operating arm to the parking position around the swing axis in response to the rotation of the drum member to the parking position.
When the cam pusher swings the parking operation arm toward the parking position in response to the rotation of the drum member to the parking position, the engagement portion of the parking operation arm is the second shifter member. When the cam pushing portion is subjected to a circumferential load exceeding the predetermined value, the drum member elastically deforms the parking coil spring and the parking pushing force is moved to the parking operation position. When the second shifter member rotates about its axis and the engaging portion and the concavo-convex portion are aligned with each other, the parking coil spring is released due to the retained elasticity accompanying elastic deformation. The parking operation arm is swung to the parking position against the biasing force of the spring to engage the engaging portion and the concavo-convex portion. Drum speed change operation mechanism according to claim 4 or 5, characterized in that to complete the. Between the first and second transmission members of the first to fourth transmission members arranged in series with each other and freely rotatable with respect to the transmission rotation shaft, the transmission rotation shaft is supported so as not to rotate relative to the transmission rotation shaft and to move in the axial direction. A first shifter member that engages with the first and second speed change members according to movement of the first side on the one side in the axial direction and the second side on the other side, and the third and fourth speed change members. The transmission rotating shaft is supported by the transmission rotating shaft so that it cannot rotate relative to the transmission rotating shaft and can move in the axial direction, and the third and fourth speed change members are uneven in response to the movement in the first axial direction and the second axial direction. A second shifter member to be engaged, a drum member having first and second fork guide grooves and operated to rotate about an axis, a fork shaft disposed in parallel to the transmission rotation shaft, and the fork shaft Supported in such a way as to be axially movable. A first shift fork having a boss portion, a first engagement pin portion engaged with the first fork guide groove and a first fork portion engaged with the first shifter member, and axial movement with respect to the fork shaft A second shift fork having a second boss portion supported by the second fork portion, a second engagement pin portion engaged with the second fork guide groove, and a second fork portion engaged with the second shifter member, The first and second shift forks are guided in the first and second fork guide grooves by the rotation of the drum member around the axis, and move in the axial direction, and the first and second shifter members are moved accordingly. A drum-type speed change operation mechanism that selectively engages with the corresponding speed change member,
A first shift fork push spring for urging the first boss portion toward the second axial direction;
A second shift fork pushing spring for urging the second boss part toward the first axial direction;
The first stop portion provided on the first boss portion is supported by the first boss portion so as to be movable in the axial direction in a state where a moving end toward the first axial direction is defined, and is provided on the drum member. A first slider member whose axial position is guided by the first slider groove;
The second stop portion provided on the second boss portion is supported by the second boss portion so as to be movable in the axial direction in a state where a moving end toward the second axial direction is defined, and is provided on the drum member. A second slider member whose axial position is guided by the second slider groove;
A first slider member pushing spring that pushes the first slider member toward the first axial direction with an urging force larger than the first shift fork pushing spring;
A second slider member pushing spring that pushes the second slider member toward the second axial direction with an urging force larger than the second shift fork pushing spring;
The first shifter member and the first shift fork are related to an axial position, the reference position where the first shifter member is not engaged with any of the first and second speed change members, and the first shifter member is the first. And the first and second shift positions that engage with the second shift member in a concave-convex manner, respectively,
The second shifter member and the second shift fork have a reference position where the second shifter member is not engaged with any of the third and fourth speed change members with respect to the axial position, and the second shifter member is third. And the third and fourth speed change positions that engage with the fourth speed change member in a concave-convex manner, respectively,
The first fork guide groove fixes the first shift fork to a reference position when the drum member is positioned at the neutral position around the axis, and the first fork guide groove is located at one side around the axis from the neutral position. The first shift fork is allowed to move between the reference position and the first shift position, and the drum member is positioned at the third operation position on one side around the axis from the first operation position. The first shift fork is fixed at the reference position, and when the drum member is positioned at the second operation position on the other side of the axis from the neutral position, the first shift fork is at the reference position and the second shift position. A groove shape for fixing the first shift fork at a reference position when the drum member is positioned at the fourth operation position on the other side around the axis from the second operation position. ,
The first slider guide groove is configured such that when the drum member is positioned at the first shift position, the first shift fork is in the state where the first slider member is in contact with the first stop portion. When the axial movement range of the first slider member is defined so that the movement between the reference position guided by one fork guide groove and the first shift position can be performed, and the drum member is positioned at the second shift position Has a groove shape for guiding the first slider member so as not to obstruct the movement between the reference position and the second shift position of the first shift fork,
The second fork guide groove fixes the second shift fork to a reference position when the drum member is positioned at the first operation position, the neutral position, and the second operation position, and the drum member operates at the third operation position. The second shift fork is allowed to move between the reference position and the third speed change position when positioned at the position, and the second shift fork is positioned when the drum member is positioned at the fourth operation position. A groove shape that allows movement between the reference position and the fourth shift position;
The second slider guide groove is configured to prevent the movement of the second shift fork between the reference position and the third shift position when the drum member is positioned at the third shift position. When the member is guided and the drum member is positioned at the fourth speed change position, the second shift fork is guided to the second fork guide while the second slider member is in contact with the second stop portion. A drum-type speed change operation mechanism characterized by having a groove shape that defines a movable range in the axial direction of the second slider member so as to be able to move between a reference position guided by a groove and a fourth speed change position. .   The first and second slider member pushing springs are single springs having one end engaged with the first slider member and the other end engaged with the second slider member. The drum-type speed change operation mechanism according to claim 7.   The axial position where the first slider member is in contact with the first stop when the first shift fork is positioned at the reference position, the first shift position, and the second shift position, respectively. In the case of the position, the first displacement position, and the second displacement position, the first slider guide groove fixes the first slider member to a reference position when the drum member is positioned at the neutral position, and When the drum member is positioned at the first operation position, the first slider member is movable between a reference position and a first displacement position, and when the drum member is positioned at the third operation position, the first slider member is movable. The first slider member is fixed at a reference position, and when the drum member is positioned at the second operation position, the first slider member is fixed at the second displacement position, and the drum member is positioned at the fourth operation position. When Drum speed change operation mechanism according to claim 7 or 8, characterized in that it has a groove shape for fixing the first slider member to the reference position.   The first slider guide groove fixes the first slider member at the second displacement position when the drum member is positioned at the second shift position, and the drum member is positioned at a position other than the second shift position. In this case, the first slider member biased toward the first axial direction by the first slider member pushing spring remains in contact with the first stop portion, and the first shift is performed. The drum-type speed change operation mechanism according to claim 7 or 8, wherein the drum-type speed change operation mechanism has a groove shape that allows the fork to move in the axial direction following the movement in the axial direction.   The axial position where the second slider member is in contact with the second stop when the second shift fork is positioned at the reference position, the third shift position, and the fourth shift position, respectively. When the position, the third displacement position, and the fourth displacement position are set, the second slider guide groove is located when the drum member is positioned between the first operation position and the second operation position with the neutral position interposed therebetween. The second slider member is fixed at a reference position, and when the drum member is positioned at the third operation position, the second slider member is fixed at the third displacement position, and the drum member is operated at the fourth operation position. 11. The groove according to claim 7, wherein the groove has a groove shape that allows the second slider member to move between a reference position and a fourth displacement position when positioned at a position. Drum-type speed change operation mechanism.   The second slider guide groove fixes the second slider member at the third displacement position when the drum member is positioned at the third shift position, and the drum member is positioned at a position other than the third shift position. When the second slider member is pressed, the second slider member urged toward the second axial direction by the second slider member pushing spring remains in contact with the second stop portion, and the second shift is performed. The drum-type speed change operation mechanism according to any one of claims 7 to 10, wherein the drum-type speed change operation mechanism has a groove shape that allows the fork to move in the axial direction following the movement in the axial direction.

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