JP2009063056A - Gear transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve durability by preventing inclination of a transmission gear on a drive side, having a projecting portion meshed with a shifter, in a gear transmission including: the transmission gear on the drive side, supported on a transmission shaft on the drive side, in a relatively rotatable and axially unmovable manner; a transmission gear on a driven side, capable of transmitting rotational force to a transmission shaft on the driven side, and meshed with the transmission gear on the drive side; and the shifter engaged with the projecting portion arranged on the transmission gear on the drive side and supported on the transmission shaft on the drive side in a relatively non-rotatable and axially movable manner, wherein the shifter is moved to a side in close proximity to the transmission gear on the drive side in order to be engaged with the projecting portion to thereby transmit rotational power of the transmission shaft on the drive side from the shifter to the transmission gear on the drive side. <P>SOLUTION: Tooth flanks 25a provided on the periphery of the transmission gear 25 on the drive side in order to be meshed with the transmission gear 26 on the driven side, are obliquely formed in such a manner that the sides thereof opposite to the shifter 35 other than the sides thereof on the side of the shifter 35, advance in the rotational direction of the transmission gear 25 on the drive side in the non-engaging condition of the projecting portion 38 with the shifter 35. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gear shift that transmits rotational power from a drive-side transmission shaft to a driven-side transmission shaft via a selected gear train among a plurality of gear trains in which a drive-side gear and a driven-side gear are always meshed. Related to machine improvements.

A drive-side transmission gear that is supported relative to the drive-side transmission shaft and is not axially movable; a driven-side transmission gear that meshes with the drive-side transmission gear so that rotational force can be transmitted to the driven-side transmission shaft; A shifter supported on the drive-side transmission shaft so as to be non-rotatable relative to the drive-side transmission shaft and movable in the axial direction. The shifter is engaged with the protrusion. A gear transmission that transmits the rotational power of the drive-side transmission shaft from the shifter to the drive-side transmission gear by moving it to the side closer to the drive-side transmission gear, and two mutually different drive-side transmission gears are integrated. A shifter configured to be coupled and supported by a drive-side transmission shaft so as not to rotate relative to the drive-side shaft and to be movable in the axial direction; A driven transmission gear that is rotatably supported on the driven transmission shaft so that connection and disconnection can be switched, and is driven by a driven transmission gear that is connected to the driven transmission shaft of the two driven gears. A gear transmission configured to transmit rotational power to a side transmission shaft is known, for example, from Patent Document 1.
JP 2004-308775 A

  By the way, when the shifter is moved close to the drive-side transmission gear side and the protrusion of the drive-side transmission gear is engaged with the shifter, the support accuracy of the drive-side transmission gear to the drive-side transmission shaft must be improved. Therefore, the drive-side transmission gear is tilted, and in order to prevent such tilting, it is necessary to strictly manage the shaft support accuracy, and improvement in productivity is desired.

  On the other hand, when two drive-side transmission gears are integrally connected to form a shifter, and the connection of the driven-side transmission gear meshing with both of the drive-side transmission gears to the driven-side transmission shaft and the disconnection thereof are switched, When one of the driven side transmission gears is connected to the driven side transmission shaft, the load acts on one side in the axial direction of the shifter, the shifter falls due to the load unbalance, and the shifter axially slides. It has become difficult to increase.

  SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and a first object of the present invention is to prevent the fall of a drive-side transmission gear having a protrusion meshing with a shifter and to improve durability, and to provide two drive-side shifts. It is a second object of the present invention to prevent the shifter configured by integrally connecting the gears from being tilted and to improve the axial slidability of the shifter.

  In order to achieve the first object, the invention according to claim 1 is directed to a drive-side transmission gear that is supported so as to be relatively rotatable and non-movable in the axial direction on the drive-side transmission shaft, and a rotational force is applied to the driven-side transmission shaft. A driven side transmission gear meshing with the drive side transmission gear so as to be able to transmit, and a protrusion provided on the drive side transmission gear so as to be able to engage with the drive side transmission shaft and being unable to rotate relative to the drive side transmission shaft. A shifter supported so as to be movable in a direction, and the rotational power of the drive-side transmission shaft is moved from the shifter by moving the shifter to a side close to the drive-side transmission gear so as to engage with the protrusion. In the gear transmission configured to transmit to the drive-side transmission gear, tooth surfaces provided on the outer periphery of the drive-side transmission gear so as to mesh with the driven-side transmission gear that is a spur gear are provided on the projecting portion and the shaft. The said shifter than the shifter-side in a non-engagement state of terpolymer, characterized in that the opposite side is formed to be inclined to advance in the direction of rotation of the drive-side transmission gear.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the movable distance of the drive side transmission gear in the direction orthogonal to the axis of the drive side transmission shaft is L1, and the drive side transmission gear is When the tooth width in the axial direction is L2, the protrusion amount of the protrusion from the drive-side transmission gear is L3, and the inclination angle of the tooth surface when the protrusion and the shifter are not engaged is θG, The inclination angle θG of the tooth surface is set in the range of θG = sin ⁻¹ {L1 / 2 (L2 + L3)} to sin ⁻¹ (L1 / L2).

  In order to achieve the second object, the invention according to claim 3 is constituted by integrally connecting two mutually different drive side transmission gears, and is relatively non-rotatable to the drive side transmission shaft and is axially arranged. A shifter that is movably supported, and a driven transmission gear that is meshed with the both drive-side transmission gears and that can be connected to and disconnected from the driven-side transmission shaft and that is rotatably supported on the driven-side transmission shaft. And the both drives are spur gears in a gear transmission configured to transmit rotational power from a driven transmission gear connected to the driven transmission shaft of the driven gears to the driven transmission shaft. The toothed surface provided on the outer periphery of one of the driven side transmission gears to mesh with one of the side transmission gears is not connected to the driven side transmission shaft of the driven side transmission gear. Opposite side, characterized in that it is formed to be inclined to advance in the direction of rotation of the driven side transmission gear and the other driven-side transmission gear than.

  The fifth-speed drive-side transmission gear 25 and the sixth-speed drive-side transmission gear 27 according to the first embodiment correspond to the drive-side transmission gear according to the first aspect of the invention, and the fifth-speed drive-side transmission gear 27 according to the first embodiment. The driven side transmission gear 26 and the sixth speed driven side transmission gear 28 correspond to the driven side transmission gear according to the first aspect of the invention, and the first shifter 35 of the first embodiment is the shifter of the first aspect of the invention. Correspond.

  The fourth-speed drive-side transmission gear 29 and the third-speed drive-side transmission gear 31 of the second embodiment correspond to the drive-side transmission gear of the invention according to claim 3, and the fourth-speed drive gear of the second embodiment. The driven side transmission gear 30 and the third speed driven side transmission gear 32 correspond to the driven side transmission gear according to the third aspect of the invention, and the first shifter 35 of the second embodiment is the shifter according to the third aspect of the invention. Correspond.

  According to the first aspect of the present invention, when the shifter is moved close to the drive-side transmission gear so as to engage with the protrusion provided on the drive-side transmission gear, the drive-side transmission shaft can rotate relative to the drive-side transmission shaft. Even if the drive-side transmission gear that is supported so as not to move in the axial direction is tilted, the tooth surface provided on the outer periphery of the drive-side transmission gear is on the opposite side of the shifter from the shifter side when the protrusion and the shifter are not engaged. Since the drive-side transmission gear is formed so as to be inclined in the rotation direction, the tooth surface of the drive-side transmission gear and the tooth surface of the driven-side transmission gear that have fallen down are parallel to each other in a direction perpendicular to the rotation direction. Since the contact surface becomes uniform, the durability can be improved.

According to the second aspect of the present invention, the inclination angle θG of the tooth surface of the drive transmission gear when the protrusion and the shifter are not engaged is set to θG = sin ⁻¹ {L1 / 2 (L2 + L3)} to sin ^{−. By} setting within the range of ¹ (L1 / L2), the contact surface between the tooth surface of the tilted drive-side transmission gear and the tooth surface of the driven-side transmission gear is made more uniform, and the durability is further improved. be able to.

  According to the third aspect of the present invention, when one of the two driven side transmission gears is connected to the driven side transmission shaft, the tooth surface provided on the outer periphery of the one driven side transmission gear is The shifter is formed so as to be inclined so that the side opposite to the other driven side transmission gear advances in the rotational direction of the driven side transmission gear rather than the other driven side transmission gear side in the non-connected state to the driven side transmission shaft. Thus, the drive-side transmission gear and the driven-side transmission gear are engaged with each other in the center in the axial direction, so that the shifter can be prevented from falling and the axial slidability of the shifter can be improved.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 3 show a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view of a gear transmission, and FIG. 2 is a diagram of a fifth speed drive side transmission gear when a first shifter is engaged. FIG. 3 is a cross-sectional view taken along line 2-2 of FIG. 1 for explaining the falling, and FIG. 3 is a schematic view showing a state in which the fifth speed drive side transmission gear has fallen.

  First, in FIG. 1, this gear transmission is mounted on a motorcycle, for example, and includes a drive-side transmission shaft 11 to which power from an engine crankshaft (not shown) can be transmitted, and a rear wheel of the motorcycle. The first to sixth speed gear trains G1, G2, G3 that can alternatively be established with the driven transmission shaft 12 to which the drive sprocket 13 around which the chain 14 for transmitting the power is wound is fixed. , G4, G5, and G6.

  The engine crankcase 15 integrally includes a side wall 15a facing outward and a support wall 15b disposed at a position spaced inward from the side wall 15a, and rotates the support wall 15b. A ball bearing 16 is interposed between the drive-side transmission shaft 11 and the support wall 15b penetrating freely, and a ball bearing 17 is interposed between the end of the drive-side transmission shaft 11 on the side wall 15a side and the side wall 15a. Is done. A driven transmission shaft 12 having an axis parallel to the drive side transmission shaft 11 passes through the side wall 15a in a freely rotatable manner. Between the side wall 15a and the driven side transmission shaft 12, a ball bearing 18 and an annular seal member are provided. 20 is interposed, and a ball bearing 19 is interposed between the end of the driven transmission shaft 12 on the support wall 15b side and the support wall 15b. In addition, the drive sprocket 13 is fixed to the protruding end portion of the driven transmission shaft 12 from the side wall 15 a of the crankcase 15.

  The first speed gear train G1 meshes with the first-speed drive-side transmission gear 21 and the first-speed drive-side transmission gear 21 that are integrally formed with the drive-side transmission shaft 11 near the support wall 15b, and is relative to the first-speed gear train G1. The first speed driven gear 22 is supported by the driven transmission shaft 12 so that it can rotate but cannot move in the axial direction. The second speed gear train G2 is a second speed drive side transmission gear 23 coupled to the end of the drive side transmission shaft 11 on the side wall 15a side of the crankcase 15 so as not to be axially movable and relatively rotatable. It comprises a second speed driven transmission gear 24 which is engaged with the second speed driving gear 23 and supported on the driven transmission shaft 12 so as not to be axially movable and relatively rotatable. The fifth speed gear train G5 is disposed at a position adjacent to the first speed gear train G1 in the axial direction, and is supported by the drive-side transmission shaft 11 so as not to be axially movable and relatively rotatable. A fifth drive-side transmission gear 25 and a fifth-speed driven transmission gear 26 that is engaged with the fifth-speed drive gear 25 and supported on the driven transmission shaft 12 so as to be relatively movable in the axial direction but not rotatable. Consists of. The sixth speed gear train G6 is disposed at a position adjacent to the second speed gear train G2 in the axial direction, and is supported by the drive-side transmission shaft 11 so as not to move in the axial direction and to be relatively rotatable. A drive-side transmission gear 27 and a sixth-speed driven-side transmission gear 28 that is engaged with the sixth-speed drive-side transmission gear 27 and that is supported on the driven-side transmission shaft 12 so as to be relatively movable in the axial direction but not rotatable. Consists of. The fourth speed gear train G4 is disposed at a position between which the fifth speed gear train G5 is sandwiched between the first speed gear train G1 and the drive side transmission shaft 11 is movable in the axial direction and is not relatively rotatable. The fourth speed driven gear shift gear 29 and the fourth speed driven gear shift gear 29 that are supported and the fourth speed driven gear supported by the driven transmission shaft 12 so as not to be axially movable and relatively rotatable. And a side transmission gear 30. Further, the third speed gear train G3 is disposed at a position where the sixth speed gear train G6 is sandwiched between the second speed gear train G2 and the fourth speed gear train G4 is sandwiched between the fifth speed gear train G5. The third-speed drive-side transmission gear 31 and the third-speed drive-side transmission gear 31 that are supported on the drive-side transmission shaft 11 so as to be axially movable and relatively non-rotatable are meshed with the third-speed drive-side transmission gear 31 and moved in the axial direction. The third-speed driven gear 32 is supported on the driven transmission shaft 12 so as to be incapable of relative rotation.

  First-speed drive-side transmission gear 21, first-speed driven-side transmission gear 22, second-speed drive-side transmission gear 23, second-speed driven-side transmission gear 24, fifth-speed drive-side transmission gear 25, Fifth-speed driven gear transmission gear 26, sixth-speed driving gear gear 27, sixth-speed driven gear gear 28, fourth-speed driving gear gear 29, fourth-speed driven gear gear 30, The third-speed driving gear 31 and the third-speed driven gear 32 are basically configured as spur gears.

  Between the fifth speed drive side transmission gear 25 and the sixth speed drive side transmission gear 27, there is disposed a first shifter 35 in which the fourth and third speed drive side transmission gears 29, 31 are integrally connected. The first shifter 35 is supported on the drive-side transmission shaft 11 so as to be movable in the axial direction and not to be relatively rotatable. A second shifter 36 is supported on the driven transmission shaft 12 between the fifth-speed driven gear shift gear 26 and the fourth-speed driven gear shift gear 30 so as to be axially movable and relatively non-rotatable. The fifth speed driven side transmission gear 26 is formed integrally with the second shifter 36. Furthermore, a third shifter 37 is supported on the driven transmission shaft 12 between the second speed driven gear 24 and the third speed driven gear 32 so as to be axially movable and relatively non-rotatable. The sixth speed driven side transmission gear 28 is formed integrally with the third shifter 37.

  Shift forks (not shown) are respectively engaged with the first to third shifters 35 to 37, and the first to third shifters 35 are operated in response to the operation of the shift forks according to the rotation of the shift drum (not shown). -37 slide.

  The first shifter 35 moves to the fifth speed drive side transmission gear 25 side and engages with the fifth speed drive side transmission gear 25 to establish a fifth speed gear train G5. Axial direction with respect to the sixth speed establishing position where the sixth speed gear train G6 is established by moving to the sixth speed driving side transmission gear 27 side and engaging with the sixth speed driving side transmission gear 27 A neutral position is set at the center between the fifth and sixth speed establishment positions and not engaged with either the fifth speed drive side transmission gear 25 or the sixth speed drive side transmission gear 27. The

  The second shifter 36 moves to the first speed driven gear 22 side and engages with the first speed driven gear 22 to establish a first speed gear train G1. Axial direction with respect to the fourth speed establishment position where the fourth speed gear train G4 is established by moving to the fourth speed driven side transmission gear 30 side and engaging with the fourth speed driven side transmission gear 30 And a neutral position is set at the center between the first and fourth speed establishment positions and is not engaged with either the first speed driven gear 22 or the fourth speed driven gear 30. The

  The third shifter 37 moves to the third speed driven gear shift gear 32 side and engages with the third speed driven gear shift gear 32 to establish a third speed gear train G3. Axial direction with respect to the second speed establishment position where the second speed gear train G2 is established by moving to the second speed driven side transmission gear 24 side and engaging with the second speed driven side transmission gear 24 A neutral position is set at the center between the third and second speed established positions and not engaged with either the third speed driven gear 32 or the second speed driven gear 24. The

  Referring also to FIG. 2, a plurality of projecting portions 38... Project from the side surface on the first shifter 35 side of the fifth-speed drive-side transmission gear 25 that is adjacent to the first shifter 35 in the axial direction. The first shifter 35 is provided with locking recesses 39 for engaging the protrusions 38. Thus, as shown in FIG. 2 (A), the protrusions 38 are engaged with the locking recesses 39 as shown in FIG. 2B from a position away from the fifth speed drive side transmission gear 25. When the first shifter 35 is moved to the side closer to the fifth-speed drive-side transmission gear 25, the rotational power of the drive-side transmission shaft 11 is changed from the first shifter 35 to the fifth as shown in FIG. It is transmitted to the speed drive side transmission gear 25.

  However, the first shifter 35 is moved closer to the fifth speed drive side transmission gear 25 and the projections 38 of the fifth speed drive side transmission gear 25 are engaged with the locking recesses 39 of the first shifter 35. 2C, the rotation of the first shifter 35 causes the fifth-speed drive-side transmission gear 25 to fall, and the fifth-speed drive-side transmission gear 25 and the fifth-speed drive gear 25 are rotated. There is a possibility that the contact load of the meshing portion of the driven gear 26 becomes non-uniform and the durability is lowered. Therefore, the tooth surfaces 25a provided on the outer periphery of the fifth-speed drive-side transmission gear 25 to be engaged with the fifth-speed driven-side transmission gear 26 are in the disengaged state of the projecting portion 38 and the first shifter 35. The side opposite to the first shifter 35 is inclined with respect to the first shifter 35 side so as to advance in the rotational direction of the fifth speed drive side transmission gear 25.

Here, the movable distance of the fifth-speed drive-side transmission gear 25 relative to the drive-side transmission shaft 11 in the direction orthogonal to the axis of the drive-side transmission shaft 11 is L1, and the axial direction of the fifth-speed drive-side transmission gear 25 is The tooth width is L2, the protrusion amount of the protrusion 38 from the fifth-speed drive-side transmission gear 25 is L3, and the tooth surface 25a when the protrusion 38 is not engaged with the first shifter 35. When the inclination angle is θG, the inclination of the fifth-speed drive-side transmission gear 25 is maximized, as shown in FIG. 3A, on the first shifter 35 side of the fifth-speed drive-side transmission gear 25. Is moved in the direction perpendicular to the axis of the drive-side transmission shaft 11 by L1, and sin θg = L1 / L2. When the first shifter 35 is engaged with the protrusions 38 and a load is applied to the protrusions 38, the fifth-speed drive-side transmission gear 25 is, as shown in FIG. Since the movement distance of the tip of the protrusions 38 with respect to the drive-side transmission shaft 11 falls while being suppressed to about L1 / 2, the preferred inclination angle θG starting from the tips of the protrusions 38 is sin θg = L1 / 2. (L2 + L3). Therefore, the inclination angle θG of the tooth surfaces 25a is set in the range of [θG = sin ⁻¹ {L1 / 2 (L2 + L3)} to sin ⁻¹ (L1 / L2)].

  Further, a plurality of projecting portions 40 are projected on the side surface on the first shifter 35 side of the sixth-speed drive-side transmission gear 27 that is adjacent to the first shifter 35 in the axial direction. Locking recesses 41 for engaging the protrusions 40 are provided. Thus, the first shifter 35 is brought close to the sixth speed drive side transmission gear 27 so that the protrusions 40 are engaged with the locking recesses 41 from a position away from the sixth speed drive side transmission gear 27. When it is moved to the driving side, the rotational power of the drive-side transmission shaft 11 is transmitted from the first shifter 35 to the sixth-speed drive-side transmission gear 27. However, when the protrusions 40 of the sixth speed drive side transmission gear 27 are engaged with the locking recesses 41 of the first shifter 35, the rotation of the first shifter 35 causes the sixth speed drive side transmission gear 27 to rotate. As a result, the contact load of the meshing portions of the sixth-speed driving gear 27 and the sixth-speed driven gear 28 becomes non-uniform, leading to a decrease in durability. Therefore, the tooth surface 2 provided on the outer periphery of the sixth-speed drive-side transmission gear 27 so as to mesh with the sixth-speed driven-side transmission gear 28 also has the protruding portion 40 as in the fifth-speed drive-side transmission gear 25. In the non-engaged state of the first shifter 35, the first shifter 35 is inclined so that the side opposite to the first shifter 35 advances in the rotational direction of the sixth-speed drive-side transmission gear 27. .

  Next, the operation of the first embodiment will be described. One of the first shifters 35 on one of the protrusions 38, 40,... Provided on the fifth speed drive side transmission gear 25 and the sixth speed drive side transmission gear 27. , The rotational power of the drive-side transmission shaft 11 is transmitted from the first shifter 35 to one of the fifth-speed drive-side transmission gear 25 and the sixth-speed drive-side transmission gear 27. Tooth surfaces 25a provided on the outer circumferences of the fifth-speed drive-side transmission gear 25 and the sixth-speed drive-side transmission gear 27 to mesh with the fifth-speed driven-side transmission gear 26 and the sixth-speed driven-side transmission gear 28. However, in the non-engaged state of the protrusions 38, 40,... And the first shifter 35, the fifth speed drive side transmission gear 25 and the sixth speed are on the opposite side of the first shifter 35 from the first shifter 35 side. Advance in the direction of rotation of the drive-side transmission gear 27 It is formed by Uni inclined.

  For this reason, the fifth-speed drive-side transmission gear 25 and the sixth-speed drive-side transmission gear 27, which are supported so as to be rotatable relative to the drive-side transmission shaft 11 but not axially movable, are engaged with the first shifter 35. Even if they fall down, the tooth surfaces 25a of the drive side transmission gears 25, 27 and the tooth surfaces of the driven side transmission gears 26, 28 mesh in parallel in the direction orthogonal to the rotational direction, and the contact surface is Since it is made uniform, durability can be improved.

In addition, the movable distance of the fifth-speed drive-side transmission gear 25 and the sixth-speed drive-side transmission gear 27 in the direction orthogonal to the axis of the drive-side transmission shaft 11 is L1, the fifth-speed drive-side transmission gear 25, and The tooth width in the axial direction of the sixth speed drive side transmission gear 27 is L2, and the protruding amount of the protrusions 38, 40,... From the fifth speed drive side transmission gear 25 and the sixth speed drive side transmission gear 27. , L3, and the inclination angle of the tooth surface 25a when the protrusions 38, 40, and the first shifter 35 are not engaged is θG, the inclination angle θG is [θG = sin ⁻¹ {L1. / 2 (L2 + L3)} to sin ⁻¹ (L1 / L2)], the tooth surfaces 25a of the drive side transmission gears 25, 27 and the driven side transmission gears 26, 28 that have fallen down. To further improve durability by making the contact surface with the tooth surface even more uniform It can be.

  FIG. 4 shows a second embodiment of the present invention. The first shifter is constructed by integrally connecting a fourth speed drive side transmission gear 29 and a third speed drive side transmission gear 31 which are different from each other. 35 is supported on the drive-side transmission shaft 11 (see FIG. 1) so as not to rotate relative to the drive-side and can move in the axial direction. The drive-side transmission gears 29 and 31 are connected to and connected to the driven-side transmission shaft 12. The fourth speed driven gear shift gear 30 and the third speed driven gear shift gear 32 that are rotatably supported on the driven transmission shaft 12 (see FIG. 1) so that the release can be switched are engaged with each other. The tooth surfaces 30a provided on the outer periphery of the fourth-speed driven transmission gear 30 to mesh with the fourth-speed driving gear 29 are not connected to the driven transmission shaft 12 of the fourth-speed driven transmission gear 30. In the connected state, the third speed driven gear 32 side The third speed driven side transmission gear 32 is inclined so that the opposite side of the fourth speed driven side transmission gear 30 rotates in the rotational direction, and the third speed driving side transmission gear 31 is engaged with the third speed driving side transmission gear 31. The tooth surfaces 32a provided on the outer periphery of the third-speed driven gear shift gear 32 are, when the third-speed driven gear gear 32 is not connected to the driven-side transmission shaft 12, the fourth-speed driven gear gear 30. The side opposite to the fourth speed driven side transmission gear 30 is inclined so as to advance in the rotational direction of the third speed driven side transmission gear 32.

  According to the second embodiment, when one of the fourth-speed driven gear shift gear 30 and the third-speed driven gear shift gear 32 is connected to the driven-side transmission shaft 12, the fourth-speed drive gear transmission gear. 29 and the third-speed drive-side transmission gear 31 and one of the fourth-speed driven-side transmission gear 30 and the third-speed driven-side transmission gear 32 are preceded by the axially central side of the first shifter 35. Thus, the first shifter 35 can be prevented from falling and the axial slidability of the first shifter 35 can be improved.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

It is a longitudinal cross-sectional view of the gear transmission of 1st Example. It is sectional drawing which follows the 2-2 line of FIG. 1 for demonstrating the fall of the drive side transmission gear for 5th speeds at the time of engagement of a 1st shifter. It is a schematic diagram which shows the state which the fall of the drive side transmission gear for 5th speed produced. It is the simplified side view of the 1st shifter vicinity of 2nd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Drive side transmission shaft 12 ... Driven side transmission shaft 25 ... 5th speed drive side transmission gear 25a, 30a, 32a ... Tooth surface 26 ... 5th speed driven side transmission gear 27... 6th speed drive side transmission gear 28... 6th speed driven side transmission gear 29... 4th speed drive side transmission gear 30. ..Third-speed drive gear 32 ... Third-speed driven gear 35 ... Shifters 38, 40 ... Projection

Claims (3)

  The drive side transmission gears (25, 27) supported so as to be relatively rotatable and non-movable in the axial direction relative to the drive side transmission shaft (11), and to transmit the rotational force to the driven side transmission shaft (12). It is possible to engage the driven side transmission gears (26, 28) meshing with the side transmission gears (25, 27) and the protrusions (38, 40) provided on the drive side transmission gears (25, 27). And a shifter (35) that is supported on the drive-side transmission shaft (11) so as not to be relatively rotatable and axially movable. The shifter (35) is engaged with the protrusions (38, 40). The rotational power of the drive side transmission shaft (11) is transmitted from the shifter (35) to the drive side transmission gears (25, 27) by moving the drive side transmission gears (25, 27) closer to the drive side. To the gear transmission A tooth surface (25a) provided on the outer periphery of the drive-side transmission gear (25, 27) to mesh with the driven-side transmission gear (26, 28), which is a spur gear, is formed on the protrusion (38, 40). And, when the shifter (35) is not engaged, the shifter (35) is inclined with respect to the side opposite to the shifter (35) so as to advance in the rotational direction of the drive side transmission gears (25, 27). A gear transmission characterized by that. The movable distance of the drive side transmission gears (25, 27) in the direction orthogonal to the axis of the drive side transmission shaft (11) is L1, and the tooth width in the axial direction of the drive side transmission gears (25, 27) is L2. The amount of protrusion of the protrusion (38, 40) from the drive-side transmission gear (25, 27) is L3, and the tooth surface when the protrusion (38, 40) and the shifter (35) are not engaged. When the inclination angle of (25a) is θG, the inclination angle θG of the tooth surface (25a) is in the range of θG = sin ⁻¹ {L1 / 2 (L2 + L3)} to sin ⁻¹ (L1 / L2) The gear transmission according to claim 1, wherein the gear transmission is set.   A shifter (35) configured by integrally connecting two different drive side transmission gears (29, 31) to each other and supported by the drive side transmission shaft (11) so as not to be relatively rotatable and axially movable; The driven side that is rotatably supported by the driven transmission shaft (12) so as to mesh with both the drive side transmission gears (29, 31) and to be able to switch between connection and release to the driven transmission shaft (12). A transmission gear (30, 32), and a rotation of the driven gear (30, 32) connected to the driven transmission shaft (12) from the driven transmission gear (12) to the driven transmission shaft (12). In the gear transmission configured to transmit power, it is provided on one outer periphery of the driven side transmission gears (30, 32) so as to mesh with one of the driving side transmission gears (29, 31) which are spur gears. Tooth surface 30a, 32a) is in a state where the driven transmission gear is not connected to the driven transmission shaft (12), and the other side of the other driven transmission gear is on the other side of the driven transmission gear than the other driven transmission gear side. A gear transmission which is formed to be inclined so as to proceed in the rotation direction.

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