JP5487065B2 - Automatic transmission - Google Patents

Description

  The present invention relates to a twin clutch transmission, and more particularly to an in-clutch automatic transmission having a dog clutch in a transmission gear.

  2. Description of the Related Art Conventionally, in a multi-stage transmission having a plurality of transmission gear pairs, a transmission gear and a sleeve that are slidably provided on a main shaft and a countershaft are moved on both shafts to change speed. There is. As this speed change operation, a configuration is known in which a speed change operation is smoothly performed by driving a shift fork that slides in parallel with the main shaft and the counter shaft.

For example, Patent Document 1 discloses an automatic transmission that automatically performs a shifting operation via an actuator.
This Patent Document 1 includes a transmission having a plurality of gear pairs between a main shaft and a counter shaft, and a twin clutch disposed on the main shaft, and the twin clutch increases the rotational driving force of the engine. This is a twin clutch transmission that is connected to and disconnected from a transmission. And in order to select one gear pair which transmits rotational drive force among several gear pairs, the slidable gear attached so that sliding was possible in the axial direction, and it was attached non-slidable in the axial direction A dog clutch is provided between the non-slidable gear. Furthermore, when the rotational driving force is transmitted by the dog clutch to the dog teeth on the protruding side of the dog clutch, the rotational driving force is transmitted by the portion that contacts the side wall surface of the concave dog hole (the dowel hole). The structure which forms the level | step difference in which the height of the axial direction was varied between the part which contact | abuts with the side wall surface of a dog hole when not done is disclosed.

JP 2009-85324 A

In the configuration disclosed in Patent Document 1, a gear is automatically switched by engaging a dowel (projection) and a dowel hole (a recess for receiving a dowel) provided in the axial direction of the gear. In the machine, as described above, in addition to a configuration in which a step having a different axial height is formed between the side surface of the dog hole and the abutting portion, there is a large rotational difference between the dowel and the dowel hole. In order to reduce the hitting sound generated in the case, the clutch is lightly connected before engagement, and the rotation difference between the engaging members is reduced.
However, in such a conventional configuration, it is difficult to properly control the amount of connection for adjusting the rotation difference due to wear of the clutch or the like. Therefore, it has been difficult to stably reduce the dog engagement sound during gear shifting.

  The present invention has been made in view of the above-described circumstances, and an object thereof is a transmission provided with a dog clutch, and an automatic transmission that can effectively and stably reduce a hitting sound caused by meshing when a gear is connected. Is to provide.

In order to achieve the above object, the invention according to claim 1 is characterized in that one adjacent gear on the same axis is provided so as not to rotate in the axial circumferential direction and to be slidable in the axial direction, and the other gear is relative to the shaft. axially to slide impossible and axially circumferentially disposed rotatably, engaged with the dowel projecting in the axial direction provided in one of the gears, a dowel hole recessed in the axial direction which is provided on the other of said gear In an automatic transmission configured to be able to switch gear positions by combining and disengaging, and configured to perform a sliding operation of the gear via a transmission mechanism ,
The number of the dowels and the size of the dowel holes are determined so that the tire movement amount corresponding to the movement distance of the dowels moving in the dowel holes after the dowels are inserted into the dowel holes is in a range of 30 mm to 50 mm. The dowel and the dowel column constituting the dowel hole are configured to have a large opposing wall surface, and the dowel and the dowel column are brought into contact with each other by the speed change mechanism when the gear position is switched. After the contact, the gears are configured to repeatedly separate and contact the gears by the speed change mechanism .

  The invention according to claim 2 is characterized in that, in addition to the configuration according to claim 1, a friction material is provided on at least one of the opposing wall surfaces of the dowel and the dowel column.

  The invention according to claim 3 is characterized in that, in addition to the configuration according to claim 2, the friction material is embedded in an opposing wall surface of the dowel or the dowel column.

  According to a fourth aspect of the present invention, in addition to the configuration according to any one of the first to third aspects, the width of the dowel column is such that the width of the dowel column provided at the high speed side shift stage is the low speed side. The width of the dowel pillar provided in the shift stage is configured to be smaller.

According to a fifth aspect of the present invention, in addition to the configuration according to any one of the first to fourth aspects, a transmission including an engagement structure between the dowel and the dowel column, and a pair of clutch mechanisms have a change-over shift. characterized in that it comprises a double clutch for switching stage.

According to the invention of claim 1, since the opposing wall surface between the dowel and the dowel column is configured to be large, the meshing opportunity between the dowel and the dowel hole is reduced, and the dowel and the dowel column are difficult to mesh. The chance of contact on the opposite wall of the is increased. In this state, the opposite wall surfaces of the dowel and the dowel column are brought into contact with each other, so that the rotational difference between the gears is reduced, and the impact when the dowel and the dowel hole are engaged is reduced, and the impact sound associated with the meshing is reduced. Becomes smaller.
According to the first aspect of the present invention, it is possible to reduce the meshing shock by lengthening the wall passing time and reducing the meshing opportunity, and suppressing the tire moving amount to a predetermined amount or less.

  According to the invention of claim 2, due to the contact of the friction material provided on the opposing wall surface, the transmission force of the rotational force at the time of contact between the dowel and the dowel column is increased, and the rotation difference between the gears can be quickly reduced. .

  According to the invention of claim 3, according to the structure in which the friction material is embedded in the opposing wall surface, the friction material can be retained so as to be caught against the force in the rubbing direction of both opposing wall surfaces of the dowel and the dowel column. It is difficult to remove and its durability can be improved.

  According to the invention of claim 4, the higher the gear stage, the larger the relative speed between the dowel and the dowel hole and the shorter the passing time between them, but the gear stage reduces the width of the dowel column in consideration of the height. By adopting the configuration, it is possible to increase the meshing opportunity and to ensure a predetermined ease of meshing.

According to the invention of claim 5 , since the twin clutch type transmission is connected to the gear of the gear stage to be switched next and stands by, the second gear that is rotating when switching to the first speed and the gear that is not rotating 6 Since the dowel and dowel hole of the high speed gear are engaged with each other, a large hitting sound is likely to be generated, but the structure of the present invention can exert an effect of reducing the hitting sound.

It is sectional drawing of the twin clutch type transmission which concerns on one Embodiment of this invention. It is a skeleton figure which shows the arrangement | positioning relationship of the transmission gear of a twin clutch type transmission. It is sectional drawing of the speed change mechanism which drives the slidable gear of a transmission. It is an expanded view which shows the shape of the guide groove of a shift drum. It is the top view seen from the dowel side of the gear C6 of the transmission TM shown in FIG. It is a perspective view of the dowel of the gear C6 of the transmission TM shown in FIG. 1, and its periphery. It is the perspective view seen from the dowel hole side of the gear C2 of the transmission TM shown in FIG. FIG. 6 is a schematic sectional view showing a non-contact state between the gear C6 and the gear C2 of the transmission TM shown in FIG. 1 (cross section taken along the line AA in FIG. 5). FIG. 2 is a schematic cross-sectional view illustrating a contact state between a gear C6 and a gear C2 of the transmission TM illustrated in FIG. FIG. 2 is a schematic cross-sectional view illustrating a meshing state between a gear C6 and a gear C2 of the transmission TM illustrated in FIG.

Hereinafter, an embodiment of the present invention will be described.
First, an embodiment of the present invention will be described in detail with reference to FIGS. In addition, each figure shall be seen in the description direction of a code | symbol.
FIG. 1 is a cross-sectional view of a twin clutch type automatic transmission 1 according to an embodiment of the present invention. FIG. 2 is a skeleton diagram showing an arrangement relationship of transmission gears of the twin clutch type automatic transmission 1.

  The automatic transmission 1 according to the present embodiment includes a twin clutch TCL including a first clutch CL1 and a second clutch CL2, and a sequential transmission TM having six forward speeds. The automatic transmission 1 is housed inside a crankcase together with an engine (not shown) as a power source for the vehicle.

With reference to FIG.1 and FIG.2, the whole structure and operation | movement of the automatic transmission 1 of this embodiment are demonstrated.
In the automatic transmission 1, a rotational driving force is transmitted from a crankshaft (not shown) of an engine to a primary gear 3 having an impact absorbing mechanism 5. This rotational driving force is output from the twin clutch TCL on the right side in the figure to the counter shaft 9 on the lower left side in the figure. That is, the twin clutch TCL is provided so as to be connectable to an outer main shaft 6 as an outer cylinder and an inner main shaft 7 as an inner cylinder rotatably supported by the outer clutch. 9 is output to the countershaft 9 via six pairs of gears provided between the counter 9 and the gear 9.
A drive sprocket 10 (see FIG. 2) is attached to one end of the counter shaft 9, and the rotational driving force of the engine is transmitted through a drive chain (not shown) wound around the drive sprocket. And transmitted to the drive wheels (not shown) of the vehicle.

  1 and 2, the transmission TM disposed on the left side of the twin clutch TCL has six gear pairs between the main shafts 6 and 7 and the counter shaft 9. This gear pair is connected via any gear pair depending on the combination of the position of the slidable gear slidably mounted in the axial direction of each axis and the connection / disconnection state of the first clutch CL1 and the second clutch CL2. It is possible to select whether to output the rotational driving force.

  The twin clutch TCL is disposed inside a clutch case 4 that rotates integrally with the primary gear 3. 2, the first clutch CL1 on the right side in the figure is non-rotatably attached to the inner main shaft 7, while the second clutch CL2 on the left side in the figure is the outer main shaft. 6 is attached to be non-rotatable. Further, as shown in FIG. 1, between the clutch case 4 and each of the clutches CL1 and CL2, five clutch plates 4a supported so as to be non-rotatable by the clutch case 4 and non-rotatable by each of the clutches CL1 and CL2. A clutch plate 12 comprising five friction plates 4b supported on the clutch plate 12 is disposed.

In the twin clutch TCL of the present embodiment, the first clutch CL1 and the second clutch CL2 generate frictional force on the clutch plate 12 by being supplied with hydraulic pressure from a hydraulic pump that is driven as the crankshaft rotates. To be switched to a connected state. In the inner main shaft 7, a distributor (not shown) that forms two double tubular hydraulic paths A0 is embedded. When hydraulic pressure is supplied to the oil passage A1 formed in the inner main shaft 7 through this distributor, the piston B1 slides to the left in the figure against the elastic force of the elastic member 11 such as a spring. The first clutch CL1 is configured to switch to the connected state. Similarly, when hydraulic pressure is supplied to the oil passage A2, the piston B2 slides to the left in the figure, and the second clutch CL2 is switched to the connected state. And piston B1, B2 of both clutch CL1, CL2 is comprised so that it may return to an original position with the elastic force of the elastic member 11, if supply hydraulic pressure falls.
The supply of hydraulic pressure to the first clutch CL1 and the second clutch CL2 is executed by switching the supply destination of hydraulic pressure that is constantly generated by a hydraulic pump that is rotated by a crankshaft, using a solenoid valve or the like.

With the configuration as described above, the rotational driving force of the primary gear 3 is such that the clutch case 4 is only rotated unless hydraulic pressure is supplied to the first clutch CL1 or the second clutch CL2. However, by supplying the hydraulic pressure, the rotational driving force of the primary gear 3 can rotate the outer main shaft 6 or the inner main shaft 7 integrally with the clutch case 4.
When the outer main shaft 6 or the inner main shaft 7 is rotated, a half-clutch state can be created by appropriately adjusting the magnitude of the supply hydraulic pressure.

  The inner main shaft 7 connected to the first clutch CL1 supports gears M1, M3, and M5 on the driving side of odd-numbered gear stages (first speed, third speed, and fifth speed). The gear M1 on the first speed drive side is formed integrally with the inner main shaft 7. The gear M3 on the third speed drive side is attached so as to be slidable in the axial direction and not rotatable in the circumferential direction. The gear M5 on the fifth speed drive side is attached so as not to slide in the axial direction and to rotate in the circumferential direction. The drive side gear M5 is provided with a dowel column 60 constituting a dowel hole 70 described later, and the drive side gear M3 adjacent to the gear M5 is provided with a dowel 50 facing the dowel column 60. It has been.

On the other hand, the outer main shaft 6 connected to the second clutch CL2 supports drive-side gears M2, M4, and M6 of even-numbered gear stages (second speed, fourth speed, and sixth speed). The gear M2 on the second speed drive side is formed integrally with the outer main shaft 6. The gear M4 on the fourth speed drive side is attached so as to be slidable in the axial direction and not rotatable in the circumferential direction. The gear M6 on the sixth speed drive side is attached so as not to slide in the axial direction and to rotate in the circumferential direction.
The drive-side gear M6 is provided with a dowel column 60 constituting the dowel hole 70, and the drive-side gear M4 adjacent to the gear M6 is provided with a dowel 50 facing the dowel column 60. .

  The counter shaft 9 supports driven gears C1 to C6 that mesh with the driving gears M1 to M6. The first to fourth speed driven gears C1, C2, C3, and C4 are attached so as not to slide in the axial direction and to rotate in the circumferential direction. On the other hand, the driven gears C5 and C6 of the fifth speed and the sixth speed are attached so as to be slidable in the axial direction and not rotatable in the circumferential direction.

  The driven gear C1 is provided with a dowel column 60 that constitutes a dowel hole 70. The driven gear C5 adjacent to the gear C1 has a dowel 50 facing the dowel column 60 (on the left side in the figure). Projecting). The driven gear C3 is provided with a dowel column 60 forming a dowel hole 70, and the driven gear C5 adjacent to the gear C3 is provided with the other dowel 50 (facing the dowel column 60). Projecting to the right in the figure). That is, the driven gear C5 has dowels 50 at both ends that can be engaged with two adjacent driven gears C1 and C3.

  The driven gear C6 also has dowels 50 at both ends that can be engaged with the two adjacent driven gears C2 and C4, similarly to the driven gear C5. , C4 and a dowel column 60 of C4.

  In the twin clutch type automatic transmission 1 according to the present embodiment, the dog clutch is applied to the structure in which the rotational driving force is connected / disconnected between the slidable gear and the non-slidable gear as described above. As shown in FIGS. 6 and 7, this dog clutch has a rotational driving force by engaging a concave-convex shape composed of a dowel 50 that is a dog tooth and a dowel hole 70 that is a dog hole (configured by a dowel column 60). introduce. This dog clutch can transmit a driving force with a small transmission loss with a simple configuration. As a result, the configuration of the transmission TM is further simplified compared to a configuration in which a synchromesh mechanism is provided between the slidable gear and the non-slidable gear to synchronize the rotation of the two. The transmission 1 can be reduced in size and weight.

  Among the gear trains described above, the driving side gears M3 and M4 and the driven side gears C5 and C6, that is, “slidable gears” arranged so as to be slidable in the axial direction are accompanied by the operation of the shift fork described later. Are configured to be slid. Accordingly, the driving gears M3, M4 and the driven gears C5, C6 are formed with engaging grooves 41, 42, 61, 62 for engaging the claw portions of the shift fork, respectively.

Further, transmission gears other than the above-described slidable gears (drive-side gears M1, M2, M5, and M6 and driven-side gears C1, C2, C3, and C4), that is, “sliding that cannot slide in the axial direction” The “impossible gear” is configured to connect and disconnect the rotational driving force between the adjacent slidable gears by the above-described dowel 50 and dowel hole 70.
With this configuration, the twin-clutch automatic transmission 1 according to the present embodiment has the position of the slidable gears (the drive side gears M3 and M4 and the driven side gears C5 and C6) and the clutches CL1. , CL2 can be arbitrarily selected as a pair of gears that transmit the rotational driving force of the engine to the driving wheels by the combination of the connected and disconnected states of CL2.

  The first clutch CL1 connects / disconnects the rotational driving force of odd-numbered gears (first speed, third speed, and fifth speed), while the second clutch CL2 connects even-numbered gear speeds (second speed, fourth speed, 6th speed). Connection of the rotational drive force at high speed. This means that when the upshift is sequentially performed, the connection state of the first clutch CL1 and the second clutch CL2 is alternately switched.

The transmission mechanism 20 of the automatic transmission 1 according to this embodiment will be described.
FIG. 3 is a sectional view of the speed change mechanism 20, and FIG. 4 is a development view showing the shape of the guide groove of the shift drum 30 of the speed change mechanism 20.
The speed change mechanism 20 according to the present embodiment slides on the two guide shafts 31 and 32 in order to drive the above-described four slidable gears (the drive side gears M3 and M4 and the driven side gears C5 and C6). Four shift forks 71, 72, 81, and 82 are movably attached.
The four shift forks 71, 72, 81, and 82 have guide claws (71 a, 72 a, 81 a, and 82 a) that engage with slidable gears, and cylindrical protrusions that engage with guide grooves formed in the shift drum 30. The parts (71b, 72b, 81b, 82b) are provided.

  A shift fork 71 that engages with the gear M3 on the third speed drive side and a shift fork 72 that engages with the gear M4 on the fourth speed drive side are attached to the guide shaft 31. A shift fork 81 that engages with the gear C5 on the fifth speed driven side and a shift fork 82 that engages with the gear C6 on the sixth speed driven side are attached to the guide shaft 32 on the other side.

  On the surface of the shift drum 30 arranged in parallel with the guide shafts 31 and 32, there are guide grooves SM1 and SM2 for engaging the shift forks 71 and 72 on the main shaft side, and shift forks 81 and 82 on the counter shaft side. Engaging guide grooves SC1 and SC2 are formed. As a result, the slidable gears M3, M4, C5, and C6 are driven along the shape of the four guide grooves as the shift drum 30 rotates.

  The shift drum 30 is rotationally driven to a predetermined position by an electric motor 21 as an actuator. The rotational driving force of the electric motor 21 is a shift drum that supports a hollow cylindrical shift drum 30 via a first gear 23 fixed to the rotary shaft 22 and a second gear 24 meshing with the first gear 23. It is transmitted to the shaft 29. The rotational position of the shift drum 30 is detected by the shift position sensor 27. The shift position sensor 27 is configured to detect the rotational position of the shift drum 30 based on the rotational position of the sensor cam 28 rotated by the sensor pin 26 embedded in the sensor plate 25 fixed to the shift drum shaft 29. Yes.

  With the configuration as described above, the automatic transmission 1 performs automatic shift control according to the engine speed, vehicle speed, etc. by performing rotation drive control of the shift drum 30 and connection / disconnection control of the twin clutch TCL in parallel. Alternatively, a semi-automatic shift (semi-automatic) that accepts a shift operation of the occupant by a shift switch or the like can be executed.

The basic operation of the positional relationship between the rotational position of the shift drum 30 and the four shift forks in this embodiment will be described below with reference to the development view of FIG.
In the present embodiment, the two guide shafts 31 and 32 are disposed at positions separated from each other by about 90 ° in the circumferential direction with respect to the rotation shaft of the shift drum 30. For example, when the rotational position of the shift drum 30 is neutral (N), the shift forks 81 and 82 are at the position of “CN” on the left side of the figure, whereas the shift forks 71 and 72 are It is in the position of the display “MNN” on the right side of the figure.
In FIG. 4, the positions of the cylindrical convex portions (71b, 72b, 81b, 82b) of the respective shift forks at the neutral time are indicated by broken line circles. In addition, a predetermined rotation position that follows from the left display “C N-N” and a predetermined rotation position that follows from the right display “M N-N” are respectively provided at intervals of 30 °. ing.

  The sliding position of the shift fork determined by each guide groove is configured such that the guide grooves SM1 and SM2 on the main shafts 6 and 7 side are in two positions of “left position” or “right position”. On the other hand, the guide grooves SC1 and SC2 on the counter shaft 9 side are configured to have three positions of “left position”, “middle position”, and “right position”.

  In the present embodiment, the shift forks (71, 72, 81, 82) at the neutral time are the shift fork 81: middle position, the shift fork 82: middle position, the shift fork 71: right position, and the shift fork 72: left In position. This is a state in which the four slidable gears driven by each shift fork are not meshed with any adjacent non-slidable gears, so even if the first clutch CL1 or the second clutch CL2 is connected. The rotational driving force of the primary gear 3 is not transmitted to the counter shaft 9.

Next, when the shift drum 30 is rotated from the neutral position described above to the positions corresponding to the first gear ("C 1-N" and "M 1-N"), the shift fork 81 is moved from the middle position. By switching to the left position, the fifth-speed driven gear C5 is switched from the middle position to the left position.
As a result, the gear C5 on the fifth-speed driven side meshes with the gear C1 on the first-speed driven side by the dog clutch so that the rotational driving force can be transmitted. In this state, when the first clutch CL1 is switched to the connected state, the inner main shaft 7 → the gear M1 on the first speed drive side → the gear C1 on the first speed driven side → the gear C5 on the fifth speed driven side → the counter shaft 9 In this order, the rotational driving force is transmitted and output from the drive sprocket 10.

  When the shift to the first gear is completed, the shift drum 30 is automatically rotated in the upshift direction by an angle of 30 degrees. This rotation operation is called “shift-up side preliminary shift” so that the shift can be completed only by switching the connected state of the twin clutch TCL when a shift command from the first speed to the second speed is issued. Is. By this shift-up side preliminary shift, the two guide shafts move relative to the shift drum 30 to the positions of the left and right displays “C1-2” and “M1-2” in the figure.

  The change in the guide groove accompanying this shift-up side preliminary shift is only that the guide groove SC2 is switched from the middle position to the right position. As a result, the shift fork 82 moves to the right position, and the driven gear C6 is driven. Meshes with the side gear C2 by a dog clutch. Since the second clutch CL2 is in the disconnected state at the time when the upshift side preliminary shift from the first speed to the second speed is completed, the outer main shaft 6 is filled with the lubricating oil filled between the inner main shaft 7 and the second main clutch CL2. It is rotated by viscosity.

  By the sliding operation of the driven gear C6 by the upshift side preliminary shift as described above, preparation for transmitting the rotational driving force via the second gear is completed. When a shift command from the first speed to the second speed is issued in this state, the first clutch CL1 is disconnected and the second clutch CL2 is switched to the connected state. By the changeover operation of the twin clutch TCL, the rotational driving force is instantaneously output via the second gear without interrupting the rotational driving force.

  When the shift operation from the first speed to the second speed is completed, the upshift side preliminary shift is performed so that the shift operation from the second speed to the third speed can be completed only by changing the twin clutch TCL. In the upshift side preliminary shift from the second speed to the third speed, the guide shaft on the countershaft 9 side moves from the display “C1-2” to the position “C3-2” on the left side of the figure, and the main shaft 6, The 7-side guide shaft moves from the display “M 1-2” on the right side of the drawing to the position of “M 3-2”. As a result, the guide groove SC1 is only switched from the left position to the right position. As a result, the shift fork 81 moves from the left position to the right position, and the gear C5 on the fifth speed driven side The gear C3 on the third speed driven side meshes with a dog clutch (a clutch structure including the dowel 50 and the dowel hole 70).

  When the up-side preliminary shift from the second speed to the third speed is completed, the connected state of the twin clutch TCL is switched from the second clutch CL2 to the first clutch CL1, in other words, only by changing the clutch, The speed change operation to the speed can be executed. This shift-up side preliminary shift is executed in the same manner until the fifth gear is selected.

At the time of the upshift side preliminary shift from the second speed to the third speed described above, the guide groove SC1 passes through the middle position in the display “CN-2” on the left side of the figure, that is, the position where the engagement by the dog clutch is not performed. The shift drum 30 can detect the angle every 30 degrees by the shift position sensor 27 and can finely adjust the rotation speed by the electric motor 21. Thereby, for example, the rotation speed from the display “C1-2” to “CN-2” on the left side of the drawing, that is, the speed at which the dog clutch is disengaged between the driven gears C1 and C5, and “CN -2 "to" C3-2 ", that is, the speed at which the dog clutch is engaged between the driven gears C5 and C3 is different, or at the position of" CN-2 " It is possible to perform a “neutral wait” that stops for a predetermined time.
Thereby, it is also possible to reduce the shift shock that is likely to occur when the dowel 50 and the dowel column 60 are connected or disconnected. Further, in the present embodiment, as will be described later, the drive timing and drive speed of the shift drum 30 can be appropriately controlled to make a desired contact between the dowel 50 and the dowel pillar 60, and the drive timing is Adjustments can be made sequentially according to the number of gears and the number of engine revolutions at the time of shifting.

Hereinafter, the meshing structure of the dowel 50 and the dowel hole 70 in the present embodiment will be described in detail with reference to FIGS. 1 and 5 to 9 by taking the driven gear C6 and the gear C2 as an example.
The gear C6 and the gear C2 are adjacent gears on the countershaft 9 axis as described above. The gear C6 is not rotatable in the axial circumferential direction of the counter shaft 9 and is slidable in the axial direction. The gear C2 is not slidable in the axial direction with respect to the counter shaft 9 and is rotatable in the axial circumferential direction. It is. The gear C6 is provided with a dowel 50 protruding in the axial direction. On the other hand, the gear C <b> 2 is provided with a dowel hole 70 that is recessed in the axial direction so as to face the dowel 50. The dowel hole 70 is configured as a recess by the dowel column 60. The sliding operation of the gear C6 can be performed via the speed change mechanism 20 as described above.

In the present embodiment, as shown in FIG. 5, the gear C <b> 6 is provided with a tooth crest 56 that meshes with the gear M <b> 6 on the outermost periphery, and the dowel 50 projects from the end face 57 in the axial direction. Six are provided. The total number of the dowels 50 is three. Further, as shown in FIG. 6, the dowel 50 is configured as an opposing wall surface 51 whose tip portion contacts the opposing wall surface 80 of the dowel column 60, and the side portion of the dowel 50 is associated with the side surface 81 of the dowel column 60. This is configured as a mating engagement side surface 50a.
The width of the dowel 50 in the gear rotation direction can be represented by an angle θ3 viewed from the center, and is configured to be, for example, about 15 degrees. As shown in the figure, two dowels 50 are arranged in close proximity to each other, and the two dowels 70 are simultaneously entered into the dowel hole 70. Moreover, the width | variety of a dowel set is comprised smaller than the width | variety of the dowel hole 70 mentioned later.
As shown in FIG. 6, the gear C6 is provided with a spline 55 on its inner periphery, and is appropriately engaged with the countershaft 9 so as to be freely slidable in the axial direction of the countershaft 9. Yes.

  On the other hand, as shown in FIG. 7, the gear C2 is provided with a tooth crest 86 that meshes with the gear M2 on its outermost periphery, and has three dowel holes 70 that are recessed in the axial direction so that the dowel 50 can enter. Three dowel pillars 60 are formed. The dowel pillar 60 has a substantially fan shape. The dowel pillar 60 has a structure in which, for example, the fan angle is about 88 degrees when the circumferential width is viewed from the center. This configuration is configured to have a width slightly more than six times that of a dowel column of a conventional manual transmission.

Further, the width of the dowel hole 70 in the gear rotation direction can be represented by an angle θ1 viewed from the center, and is configured to be, for example, slightly over 31 degrees. Similarly, the dowel column 60 is configured such that the angle θ2 viewed from the center is slightly over 88 degrees.
As shown in FIG. 7, the gear C <b> 2 has an inner peripheral surface that is a flat surface, and is configured such that the counter shaft 9 is appropriately positioned in the axial direction so as to be rotatable around the axis of the counter shaft 9. Has been.

  The gear C2 and the gear C6 configured as described above are disposed so as to face each other so that the dowel 50 and the dowel hole 70 can be engaged with each other, as shown in an enlarged view in FIG. That is, when the gear C6 slides (moves in the direction of the arrow Z3 in FIG. 10) with respect to the gear C2, the dowel 50 enters the dowel hole 70 and meshes with it, but the structure as described above in this embodiment. According to this, it is set so that the engagement opportunity between the dowel 50 and the dowel hole 70 is reduced. In particular, this set value is set to be smaller than that of a conventional transmission that manually performs the sliding operation of the gear C6.

  In the present embodiment, the opposing wall surfaces 51 and 80 of the dowel 50 and the dowel pillar 60 constituting the dowel hole 70 are configured to be large. Further, not only the opposed wall surfaces 51 and 80 are configured to be large, but also the opposed wall surfaces 51 and 80 of the dowel 50 and the dowel column 60 are positioned as shown in FIG. 9 to the position shown in FIG. 9 (movement in the direction of arrow Z1), and after contact, the transmission mechanism 20 further separates the gear C2 from the gear C6 (movement in the direction of arrow Z2) and contacts (movement). The movement in the direction of arrow Z1) is repeated.

As described above, since the opposing wall surfaces 51 and 80 between the dowel 50 and the dowel pillar 60 are configured to be large, the engagement opportunity between the dowel 50 and the dowel hole 70 is reduced, and it becomes difficult to engage with the dowel 50. Opportunities for contact with the dowel pillars 60 on the opposing wall surfaces 51 and 80 are increased. As a result, the time for rubbing by the opposing wall surfaces 51 and 80 becomes longer.
Therefore, by performing a long rubbing due to the contact between the opposing wall surfaces 51 and 80 of the dowel 50 and the dowel column 60, the rotational difference between the rubbing gears becomes small.
In a state where the mutual rotation difference between the gears is small, the dowel 50 enters the dowel hole 70 (movement indicated by the arrow Z3) as shown in FIG. In this way, when the dowel 5 enters the dowel hole 70, when the dowel 5 is engaged with the side surface 91 of the dowel column 60, the impact at the time of engagement is small, and the hitting sound accompanying the meshing is almost generated. There is nothing.

In the present embodiment, as shown in FIG. 7, friction materials 80 a are respectively provided on the opposing wall surfaces 80 of the three dowel pillars 60. When the friction material 80a provided on the opposing wall surface 80 comes into contact with the opposing wall surface 51 on the dowel 50 side, the frictional force between the opposing wall surfaces 51 and 80 can be increased, and the rotation between the gears C2 and C6 can be increased. The difference can be quickly reduced.
The material of the friction material 80a is not particularly limited as long as the friction material 80a has higher friction than the opposing wall surface 80 and has excellent durability.

  In the present embodiment, the friction material 80 a is embedded in the opposing wall surface 80 of the dowel pillar 60. That is, it is a structure embedded in an appropriate recessed structure portion formed on the opposing wall surface 80. According to this structure, it can hold | maintain so that the friction material 80a may be caught with respect to the force of the rubbing direction of both the opposing wall surfaces 51 and 80 of the dowel 50 and the dowel pillar 60. FIG. Therefore, the friction material 80a is held on the opposing wall surface 80 for a long time, and the durability thereof is increased.

In the present embodiment, the number of dowels 50 is three and the number of dowel holes 70 is also three. This is because the number of dowel holes 70 is reduced compared to a structure in which the number of dowels and the number of dowel holes are both about eight in the prior art. The dowel pillar 60 can be formed wider in the direction and wider.
By configuring the dowel pillar 60 to have a large width in this way, it is possible to increase the rate at which the dowel 50 and the opposing wall surfaces 51 and 80 of the dowel pillar 60 abut. This can reduce the rotational difference between the gears C2 and C6 by the frictional force accompanying the contact. Further, for example, if the width of the dowel column 60 is increased while keeping the number of dowel holes 70 the same, the probability of meshing will be too small, but the number of dowel holes 70 will be reduced to open one by one. Thereby, the meshing opportunity of the dowel 50 and the dowel hole 70 can be maintained at a predetermined ratio.

  Moreover, in this embodiment, the width | variety of the dowel pillar 60 can be enlarged as mentioned above by reducing the number of dowel holes 70, and the facing wall surfaces 51 and 80 of the dowel 50 and the dowel pillar 60 are provided. In addition to increasing the abutment ratio, the number of dowels 50 and the number of dowel holes 70 are greatly reduced, so that the dowel hole openings can be opened larger, so that the meshing opportunity can be maintained at a predetermined ratio.

In this embodiment, the dog clutches of the dowels 50 and the dowel holes 70 are received at six locations. However, the dowel column 60 is low in width as compared with the dowel column 60 provided at the high speed side gear. It is configured to be smaller than the width of the dowel column 60 provided in the side shift stage. That is, the gear C2 and gear C6, the gear C4 and gear C6, the gear C1 and gear C5, the gear C3 and gear C5, the gear M6 and gear M4, and the gear M3 and gear M5, which are dog clutch structures, The width of the provided dowel pillar 60 is configured to be small.
This is because the higher the gear position, the greater the relative speed between the dowel 50 and the dowel hole 70 and the shorter the passing time between them, but the gear stage is configured to reduce the width of the dowel column 60 in consideration of the height. Thus, it is possible to avoid a reduction in meshing opportunities and to ensure a predetermined meshing ease.

In this embodiment, it is comprised so that a favorable result may be obtained with respect to the drive tire connected via the chain spanned over the drive sprocket 10 (refer FIG. 2). That is, the number of dowels 50 and the size of the dowel holes 70 are set such that the tire movement amount corresponding to the movement distance of the dowels 50 moving in the dowel holes 70 is equal to or less than a predetermined amount.
In this way, in the dog clutch of the dowel 50 and the dowel hole 70, the rotational difference between the gears of the clutch portion is reduced, and the tire movement amount is suppressed to a predetermined amount or less. The meshing shock is reduced, and the power transmission to the drive tire is smooth.

  Normally, when changing the gear stage of the twin clutch TCL, the gear of the gear stage to be switched next is connected and waits. For example, when the gear is switched to the first gear, the second gear is rotating. Since the 6-speed gear dowel 50 and the dowel hole 70 are engaged with each other, a particularly loud sound is likely to be generated, but in this embodiment, as described above, the gear having the dowel 50 and the gear having the dowel hole 70 are Since the rotational speed difference can be almost eliminated, the effect of reducing the hitting sound can be exhibited extremely effectively.

Hereinafter, with reference to FIG. 1, FIG. 8, FIG. 9, and FIG. 10, the operation of the dog clutch during the shift operation from the first speed to the second speed will be described in detail.
First, during traveling in the first speed gear to which the first clutch CL1 is connected, the rotational driving force of the inner main shaft 7 is transmitted from the first speed driven gear C1 to the fifth speed driven gear C5. Yes.
At this time, the rotational driving force T of the inner main shaft 7 rotates the gear C1 on the first speed driven side in the clockwise direction in the figure, and the gear C5 on the fifth speed driven side connected by the dog clutch follows this. Are rotated clockwise.

The first clutch CL1 is disengaged and the second clutch CL2 is connected in accordance with the shift command from the first speed to the second speed.
That is, the connection state is switched from the first clutch CL1 to the second clutch CL2.

Next, the relationship between the second speed driven gear C2 and the sixth speed driven gear C6 during the shifting operation from the first speed to the second speed will be described.
8 and 9 show a state immediately before switching from the first clutch CL1 to the second clutch CL2, and FIG. 10 shows a state where switching to the second clutch CL2 has been performed.

  During traveling at the first speed, the rotational driving force from the outer main shaft 6 does not act on the gear C2 on the second speed driven side and the gear C6 on the sixth speed driven side. At this time, the outer main shaft 6 is driven and rotated by the viscosity of the lubricating oil filled between the outer main shaft 6 and the inner main shaft 7. Thereby, the gear C2 on the second speed driven side rotates in the clockwise direction. The rotational speed of the second driven gear C2 is faster than the rotational speed of the sixth speed driven gear C6 rotated by the countershaft 9.

When the connection state is switched from the first clutch CL1 to the second clutch CL2 in accordance with the shift command from the first speed to the second speed, the rotational driving force T of the outer crankshaft 6 is changed to the second speed driven gear. It acts on C2 (state shown in FIG. 8).
Then, as shown in FIG. 9, drive operation (movement in the direction of arrow Z <b> 1) is performed by the speed change mechanism 20 so that the opposing wall surface 51 contacts the other opposing wall surface 80. After contact of the opposing wall surfaces 51 and 80 by the movement of the gear C6 (the state shown in FIG. 9), the gear C6 is separated again (the state shown in FIG. 8 by the movement in the direction of the arrow Z2) and again the gear C6 on the sixth speed driven side. Is moved closer to the gear C2 side on the second speed driven side.
As a result, when the dowel 50 can enter the dowel hole 70, the dowel 50 and the side surface 91 of the dowel column 60 are engaged, this state is maintained, and the upshift to the second speed is completed.

In addition, when the dowel 50 cannot enter the dowel hole 70 due to a single reciprocating movement between the opposing wall surface 51 and the opposing wall surface 80, the contact between the opposing wall surfaces 51 and 80 is automatically repeated. ing.
That is, when the opposing wall surfaces 51 and 80 are contacted a plurality of times, the difference in rotational speed between the second-speed driven gear C2 and the sixth-speed driven gear C6 is almost eliminated as the contact time becomes longer. When the dowel 50 and the side surface 91 of the dowel column 60 are engaged, the generation of hitting sound is further suppressed.

Hereinafter, an embodiment in which the automatic transmission according to the present invention is applied will be described in comparison with a comparative example.
In addition, what was implemented is a motorcycle, and Examples 1-4 are the twin clutch type automatic transmission 1 shown in FIG. Comparative Examples 1 to 4 are cases where the present invention is applied to a manual transmission for a motorcycle.

Example 1
In this example, the structure of the dowel and the dowel column in the first speed was set as the following conditions.
Implementation conditions 1) Number of dowels of gear C5: 3 2) Dowel angle (θ3): 20.9 degrees 3) Number of dowel pillars: 3 4) Dowel pillar angle (θ2): 83 degrees 5) Dowel hole Angle (θ1): 37 degrees (Comparative Example 1)
In this comparative example, the structure of the dowel and the dowel column in the first speed was set as the following conditions.
Implementation conditions 1) Number of gear C5 dowels: 7 2) Dowel angle (θ3): 20.9 degrees 3) Number of dowel pillars: 7 4) Dowel pillar angle (θ2): 14.5 degrees 5) Dowel hole angle (θ1): 37 degrees

The evaluation of Example 1 and Comparative Example 1 will be described.
Here, there were four evaluation items: a) chance of meshing (%), b) tire travel (mm), c) dowel hole passage time (msec), and d) counter wall surface passage time (msec).
The engagement chance here is a probability (%) that the dowel 50 can enter the dowel hole 70, and the tire movement amount is a driving tire due to the play (gap in the rotation direction) of the dowel 50 in the dowel hole 70. The dowel hole passage time is the time for the dowel 50 to pass through the dowel hole 70 at the specified engine speed (the time during which the dowel 50 can be engaged), and the opposite wall surface passage time. The time when the opposing wall surface 51 of the dowel 50 passes the opposing wall surface 80 of the dowel column 60 at the specified engine speed (the time when the dowel 50 cannot be engaged).

(Measurement result)
a) Engagement chance (%): Comparative Example 1 is 31.3%, while Example 1 is 13.4%
b) Tire travel (mm): 36 mm for both Comparative Example 1 and Example 1.
c) Dowel hole passing time (msec): 5.4 msec for both Comparative Example 1 and Example 1
d) Opposite wall surface passage time (msec): Comparative Example 1 is 11.8 msec, Example 1 is 34.7 msec

(Example 2)
In Example 2, the structure of the dowel and the dowel column at the second speed was set as the following conditions.
Implementation condition 1) Number of dowels of gear C6: 3 2) Dowel angle (θ3): 15.0 degrees 3) Number of dowel pillars: 3 4) Angle of dowel pillar (θ2): 88.4 degrees 5) Dowel hole angle (θ1): 31.6 degrees (Comparative Example 2)
In this comparative example 2, the structure of the dowel and the dowel column at the second speed was set as the following condition.
Implementation conditions 1) Number of gear C2 dowels: 8 2) Dowel angle (θ3): 20.9 degrees 3) Number of dowel pillars: 8 4) Dowel pillar angle (θ2): 13.4 degrees 5) Dowel hole angle (θ1): 31.6 degrees

The evaluation of Example 2 and Comparative Example 2 will be described.
(Measurement result)
a) Engagement chance (%): Comparative Example 2 is 36.9%, while Example 2 is 13.8%
b) Tire travel (mm): 37 mm for both Comparative Example 2 and Example 2.
c) Dowel hole passage time (msec): 5.5 msec for both Comparative Example 2 and Example 2
d) Opposite wall surface passage time (msec): Comparative Example 2 is 9.5 msec, Example 2 is 34.5 msec

(Example 3)
In Example 3, the structure of the dowel and the dowel column at the third speed was set as the following conditions.
Implementation conditions 1) Number of dowels of gear C5: 3 2) Dowel angle (θ3): 14.9 degrees 3) Number of dowel pillars: 3 4) Angle of dowel pillar (θ2): 88.0 degrees 5) Dowel hole angle (θ1): 32.0 degrees (Comparative Example 3)
In Comparative Example 3, the structure of the dowel and the dowel column at the third speed was set as the following condition.
Implementation conditions 1) Number of dowels of gear C3: 8 2) Angle of dowels (θ3): 14.9 degrees 3) Number of dowel columns: 8 4) Angle of dowel columns (θ2): 12.9 degrees 5) Dowel hole angle (θ1): 32.1 degrees

The evaluation of Example 3 and Comparative Example 3 will be described.
(Measurement result)
a) Engagement chance (%): Comparative Example 3 is 38.2%, while Example 3 is 14.3%.
b) Tire travel (mm) ......... 38 mm for both Comparative Example 3 and Example 3.
c) Dowel hole passage time (msec): 5.3 msec for both Comparative Example 3 and Example 3
d) Opposite wall surface passage time (msec): Comparative Example 3 is 8.6 msec, Example 3 is 31.6 msec

(Example 4)
In Example 4, the structure of the dowel and the dowel column at the fourth speed was set as the following conditions.
Implementation conditions 1) Number of dowels of gear C6: 3 2) Dowel angle (θ3): 21.0 degrees 3) Number of dowel columns: 3 4) Dowel pillar angle (θ2): 88.0 degrees 5) Dowel hole angle (θ1): 32.0 degrees (Comparative Example 4)
In Comparative Example 4, the structure of the dowels and dowel pillars at the third speed was set as the following conditions.
Implementation conditions 1) Number of dowels of gear C3: 7 2) Dowel angle (θ3): 21.0 degrees 3) Number of dowel pillars: 7 4) Angle of dowel pillar (θ2): 11.0 degrees 5) Dowel hole angle (θ1): 40.4 degrees

The evaluation of Example 4 and Comparative Example 4 will be described.
(Measurement result)
a) Engagement chance (%): Comparative Example 4 is 37.7%, while Example 4 is 14.8%
b) Tire travel (mm): 43mm for both Comparative Example 4 and Example 4.
c) Dowel hole passage time (msec): 6.7 msec for both Comparative Example 4 and Example 4
d) Opposite wall surface passage time (msec): Comparative Example 4 is 11.0 msec, Example 3 is 30.6 msec

From the above results, in Examples 1, 2, 3, and 4, compared to Comparative Examples 1, 2, 3, and 4, the upper meshing chance is small and the opposing wall surface passage time is increased, so that the dowel 50 and the dowel column 60 come into contact with each other. It can be seen that the time can be increased and the rotation difference between the gears can be reduced.
Further, the time during which the dowels 50 can be engaged is not reduced, and the engagement is maintained. Further, the amount of tire movement is almost the same as that of the comparative example, and the smoothness at the time of the shift change is improved as much as the difference in rotation between the gears can be reduced.
The amount of tire movement is suitably about 30 mm to 50 mm. If it is too short, the dog engagement chance becomes too small, and if it is too large, the shock at the time of engagement becomes large.

As described above, in the structure of the dowel 50 and the dowel column 60 in the embodiment to which the present invention is applied, the friction material 80a is provided on the dowel column 60. However, in the present invention, the friction material 80a is provided on the dowel 50. Alternatively, a structure provided on both the dowel 50 and the dowel pillar 60 may be used. Moreover, although the friction material 80a in the above-described embodiment is configured to be provided on a part of the opposing wall surface 80, in the present invention, for example, a configuration in which the entire opposing wall surface 80 is the friction material 80a, The surface of the wall surface 80 may be processed to increase the dynamic friction coefficient.
In the above-described embodiment, the gear change in the case of upshifting has been described. However, the present invention is set to operate in the same way during the downshifting.

DESCRIPTION OF SYMBOLS 1 Automatic transmission 3 Primary gear 4 Clutch case 5 Shock absorption mechanism 6,7 Main shaft 9 Counter shaft 10 Drive sprocket 20 Transmission mechanism 30 Shift drum 50 Dowel 51 Opposite wall surface 60 Dowel pillar 70 Dowel hole 80 Opposite wall surface 80a Friction material 91 Side surface C1, C2, C3, C4, C5, C6 Driven side gear M1, M3, M4, M5, M6 Drive side gear TCL Twin clutch CL1 First clutch CL2 Second clutch TM Transmission

Claims (5)

One gear (M3, M4, C5, C6) adjacent on the same axis is provided so as not to rotate in the axial circumferential direction and to be slidable in the axial direction, and the other gear (C1, C2, C3, C4, M4, M5). And a dowel (50) which is provided so as to be non-slidable in the axial direction relative to the shaft and rotatable in the axial circumferential direction, and which projects in the axial direction provided on one of the gears (M3, M4, C5, C6). The other gear (C1, C2, C3, C4, M4, M5) is configured to be capable of switching the gear position by engaging and disengaging the dowel hole (70) recessed in the axial direction. At the same time, in the automatic transmission (1) configured to perform the sliding operation of the gears (M3, M4, C5, C6) via the transmission mechanism (20),
The number of the dowels (50) and the size of the dowel holes (70) are set so that the dowels (50) move in the dowel holes (70) after the dowels (50) are fitted into the dowel holes (70). ) Is provided so that the amount of movement of the tire corresponding to the travel distance of 30 mm to 50 mm, and the opposing wall surface (51, 50) between the dowel (50) and the dowel pillar (60) constituting the dowel hole (70). 80), and when the gears are switched, the opposing wall surfaces (51, 80) of the dowel (50) and the dowel post (60) are brought into contact with each other by the speed change mechanism (20). The automatic transmission is configured to repeatedly separate and contact the gears (C1, C2, C3, C4, M4, M5, M3, M4, C5, C6) by the transmission mechanism (20). Transmission (1).   The automatic transmission according to claim 1, wherein a friction material (80a) is provided on at least one of the opposing wall surfaces (51, 80) between the dowel (50) and the dowel post (60). (1).   The automatic transmission (1) according to claim 2, wherein the friction material (80a) is embedded in an opposing wall surface (51, 80) of the dowel (50) or the dowel post (60). .   The width of the dowel column (60) is configured such that the width of the dowel column (60) provided at the high speed side shift stage is smaller than the width of the dowel column (60) provided at the low speed side shift stage. The automatic transmission (1) according to any one of claims 1 to 3, wherein the automatic transmission (1) is provided. The transmission (TM) provided with an engagement structure between the dowel (50) and the dowel post (60), and a twin clutch (TCL) in which a pair of clutch mechanisms change over and change gears. Item 5. The automatic transmission (1) according to any one of Items 1 to 4 .

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