JPS6242189B2 - - Google Patents

Description

Detailed Description of the Invention A. Object of the Invention (1) Industrial Application Field The present invention provides a main transmission mechanism having a gear train with a plurality of gears that can be selectively established, and a sub-transmission mechanism having a reduction gear train for achieving an extremely low speed lower than A select arm that engages with the shift piece is integrated into a select shaft that can rotate about orthogonal axes, and the selection position of each gear train by the shift piece can select each gear train of the main transmission mechanism. The present invention relates to a vehicle transmission in which a position where a reduction gear train of a sub-transmission mechanism is set and a position where a reduction gear train of a sub-transmission mechanism can be selected are shifted in the axial direction of a shift piece shaft.

(2) Conventional technology Conventionally, vehicle transmissions, especially manual transmissions, have four
Although the vehicle has up to five forward gears, an all-wheel drive vehicle requires an extremely low speed, which is even lower than the lowest gear, depending on the driving condition. When driving at this extremely low speed, the large load caused by the gear train with a large reduction ratio is shared between the front and rear differentials.
An excessive load is not applied to one differential device. However, for vehicles that can switch between all-wheel drive and front-wheel drive or rear-wheel drive, selecting extremely low speed when driving the front or rear wheels may place an excessive load on either the front or rear differential. There is a risk that it will work.

(3) Problems to be Solved by the Invention The present invention has been made in view of the above circumstances, and provides a system for easily switching between a state in which selection of extremely low speed is possible and a state in which selection of extremely low speed can be prevented. It is an object of the present invention to provide a vehicle transmission equipped with an interlock mechanism that enables interlocking.

B. Structure of the Invention (1) Means for Solving the Problems According to the present invention, a protrusion is provided on the select shaft or the select arm, and an extremely low speed interlock plate that can come into contact with the protrusion is arranged to It is arranged to be movable between a position that prevents rotation of the select shaft in the direction of moving the shift piece to a position for selecting a gear train, and a position that allows the rotation.

(2) Operation By rotating the interlock plate, rotation of the select shaft, that is, movement of the shift piece, to the position where extremely low speed is selected is prevented.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. First, in FIG. 1, the engine E is installed horizontally at the front of the vehicle body, that is, its crankshaft 1 is perpendicular to the direction of travel of the vehicle. It is arranged like this. A transmission device consisting of a clutch 2, a transmission 3, a front wheel drive differential 4 and a transfer 5 is disposed on one side of the engine E. The driving force of engine E is provided by clutch 2 and transmission 3.
The transmission is transmitted to the front wheel drive differential 4 via the drive shafts 6, 7, constant velocity joints 8, 9, transmission shafts 10, 11, and constant velocity joints 12, 13 to the left and right front wheels 14, 15. transmitted to. Also,
The driving force of the engine E is selectively transmitted to the drive shaft 16 via the transmission 3 and transfer 5. The driving force of the drive shaft 16 is transmitted to the rear wheel drive differential 20 via the universal joint 17, propeller shaft 18, and universal joint 19, and from the differential 20 to the drive shafts 21, 22, etc. It is transmitted to left and right rear wheels 29, 30 via velocity joints 23, 24, transmission shafts 25, 26, and constant velocity joints 27, 28.

In FIG. 2 showing details of the transmission device, a clutch case 32 is integrally secured to one side of a crankcase 31 of an engine E, and a transmission case 33 is further integrally secured to this clutch case 32.

A conventionally known clutch 2 is housed in the clutch case 32, and a transmission 3 is housed in the transmission case 33. The transmission 3 is a main transmission mechanism 36
and a sub-transmission mechanism 37, and a main transmission mechanism 36.
is a first speed gear train G1, a second speed gear train G2, and a third speed gear train G between an input shaft 38 coaxial with the crankshaft 1 and an output shaft 39 parallel to the input shaft 38.
3. A fourth speed gear train G4, a fifth speed gear train G5, and a reverse gear train Gr are provided. The driving force transmitted from the input shaft 38 to the output shaft 39 via the selected gear train among these gear trains G1, G2, G3, G4, G5, and Gr is transmitted to the output shaft at the end closer to the engine E. It is output from an output gear 40 provided at 39.

Referring also to FIG. 3, the sub-transmission mechanism 37 is as follows:
It is used for extremely low speeds below the first speed during all-wheel drive, and the input shaft 38 and output shaft 3
9 and an intermediate shaft 70 and a sub-shaft 71, which are arranged in a part of the transmission case 33 closer to the clutch 2. The intermediate shaft 70 is connected to the clutch case 32
The intermediate shaft 70 is fixedly supported at both ends by a transmission case 33 and a gear 72 integrated with the input shaft 38 to form a first gear train G1. A sub-input gear 73 is rotatably supported. Further, the subshaft 71 is rotatably supported by the clutch case 32 and the transmission case 33, and the subshaft 71 is supported by the output shaft 3.
A sub-output gear 75 is integrated with the reduction gear 41 integrated with the gear 9 . In addition, the sub input gear 7
3 and a gear 77 that is relatively rotatably supported by the subshaft 71 are always meshed to form a reduction gear train 78. The auxiliary input gear 73, the reduction gear train 78, and the auxiliary output gear 75
constitutes an extremely low speed gear train Gsl.

The auxiliary input gear 73 and the gear 76 are integrated and are provided at both ends of a cylindrical body 74 with a bearing 79 interposed between it and the intermediate shaft 70 . That is, the auxiliary input gear 73 is integrated with one end of the cylindrical body 74 on the side of the clutch case 32, and the gear 76 is integrated with the other end of the cylindrical body 74. Further, a cylindrical collar 81 having a support collar 80 on the side of the auxiliary input gear 73 and surrounding the intermediate shaft 70 is disposed between the auxiliary input gear 73 and the clutch case 32. A thrust bearing 8 is provided between the collar 80 and the sub-input gear 73.
2 is interposed.

On the other hand, the gear 76 and the transmission case 33
A thrust bearing 83, a washer 84, a disc spring 85, and a washer 86 are interposed in order from the gear 76 side.

When the sub-transmission mechanism 37 is assembled, the intermediate shaft 70 has the cylindrical body 74 and the collar 81 in a state where the sub-input gear 73 and the gear 76 are meshed with the gear 72 of the input shaft 39 and the gear 77 of the sub-shaft 71, respectively. It is inserted through the tube, and is basically formed into a straight columnar shape. Furthermore, a rotation stopper projection 87 is provided on one end surface of the intermediate shaft 70 on the clutch case 32 side.
is installed protrudingly. On the other hand, in the clutch case 32,
A support hole 88 having a circular cross section is bored into which one end of the intermediate shaft 70 is fitted and supported.
A recess 89 into which the rotation stopper protrusion 87 is fitted is provided on the bottom surface of the recess 89 .

In FIG. 4, the rotation stopper projection 87 is
The cross section of the recess 89 is approximately semicircular, and the cross section of the recess 89 is also shaped like the rotation stopper projection 8.
It is formed into a semicircle corresponding to 7.

The transmission case 33 also has a support hole 90 with a circular cross section that fits and supports the other end of the intermediate shaft 70.
is provided.

Further, the subshaft 71 is rotatably supported by the clutch case 32 and the transmission case 33, and is supported by recesses 91 and 92 provided in the clutch case 32 and the transmission case 33, respectively.
It is supported via bearings 93 and 94.

Referring again to FIG. 2, the gear box 44 of the front wheel drive differential 4 is rotatably supported by the clutch case 32 and the transmission case 33. The reduction ring gear 42 meshing with the reduction ring gear 4
A drive gear 43 having a diameter smaller than that of 2 is fixed in parallel. In addition, a pair of left and right front wheel drive shafts 6 and 7 are protruded and arranged to face each other in the gear box 44, and a support shaft 45 that is perpendicular to the drive shafts 6 and 7 is arranged between the two drive shafts 6 and 7. Fixed. Also, bevel gears 46 and 47 are fixed to both ends of the support shaft 45, and bevel gears 46 and 47 are fixed to the inner ends of the drive shafts 6 and 7.
Bevel gears 48 and 49 meshing with gear 7 are spline-coupled.

Clutch case 32 and transmission case 3
3 extends to the rear of the front wheel drive differential 4, and a transfer case 50 is integrated with the rear end of the clutch case 32 to form a chamber 52 for accommodating the transfer 5. is fixed to. The transfer 5 includes a transfer shaft 53 parallel to the pair of drive shafts 6 and 7,
The transfer shaft 53 is connected to each case 32,
It is rotatably supported by 33 and 50. A drive gear 4 integral with the gear box 44 is disposed at the end of the transfer shaft 53 closer to the transmission case 33.
A driven gear 54 that is always in mesh with the transfer shaft 53 and the driven gear 5 is rotatably supported.
4 is provided with a gear clutch mechanism 55 for transversely transmitting power therebetween.

The gear clutch mechanism 55 includes a gear 56 integrally provided on one side of the driven gear 54, and a gear 58 provided at one end of a collar 57 spline-coupled to the transfer shaft 53, and is slidable in the axial direction. A sleeve 59 that is always engaged with the gear 58 and can be engaged with and detached from the gear 56, a yoke 60 that is engaged with the outer periphery of the sleeve 59, and a transfer shaft 5 that is driven to swing with the yoke 60.
3 and a swing shaft 61 which is pivoted on the clutch case 32 and perpendicular to the clutch case 32. An actuator 62 such as a negative pressure actuator is connected to this swing shaft 61, and the swing shaft 61, that is, the yoke 60 is swing-driven by the actuator 62.

In this gear clutch mechanism 55, when the actuator 62 swings the yoke 60 to the right in FIG. The driving force of the gear 54 is transferred to the transfer shaft 5
3. Further, when the yoke 60 is swung to the left as shown in FIG. 2, the sleeve 59 is released from the meshing state with the gear 56.
Power transmission between driven gear 54 and transfer shaft 53 is interrupted.

A drive bevel gear 63 is fixed to the end of the transfer shaft 53 on the transfer case 50 side, and the drive bevel gear 63 meshes with a driven bevel gear 64 . The driven bevel gear 64 is integrally provided at the end of the drive shaft 16.
is disposed perpendicular to the transfer shaft 53 and is rotatably supported by a bearing sleeve 66 disposed astride the clutch case 32 and transfer case 50.

Next, the configuration for selecting each gear train G1, G2, G3, G4, G5, Gr in the main transmission mechanism 36 of the transmission 3 and the very low speed gear train Gsl in the auxiliary transmission mechanism 37 will be described. The output shaft 39 between the second speed gear trains G1 and G2 is connected to the gear train G by moving the select sleeve 96 to the left or right.
A synchronizing mechanism 97 for switching the first and second speeds is installed to switch between the connected state of the output shaft 39 and the output shaft 39.
A shift fork 98 for switching between first and second speeds is engaged with the select sleeve 96 . Further, the input shaft 38 between the third and fourth speed gear trains G3 and G4 is provided with third and fourth gears that switch the connection state between both the gear trains G3 and G4 and the input shaft 38 by moving a select sleeve 99 to the left or right. A speed switching synchronization mechanism 100 is installed, and a shift fork 101 for third and fourth speed switching is engaged with the select sleeve 99. Furthermore, a fifth speed switching synchronizing mechanism 102 for switching the connection state of the fifth speed gear train G5 with the input shaft 38 is attached to the end of the input shaft 38 on the side separated from the clutch 2. Select sleeve 10
3 is engaged with a shift fork 104 for switching to the fifth speed.

The reverse gear train Gr is provided integrally with the drive gear 105 integrated with the input shaft 38 and the select sleeve 99 of the first and second speed switching synchronization mechanism 97, and is prevented from rotating relative to the output shaft 39. driven gear 1
06, and an idle gear 107 that is movable between a position in which it meshes with the drive gear 105 and a driven gear 106, and a position in which it disengages.
In other words, as shown in FIG.
The idler gear shaft 108 is slidably supported on an idler gear shaft 108 that is fixedly supported at the idler gear shaft 108 . This idle gear 10
7 is held by a reverse shift fork 109, and by the operation of the shift fork 109, the idle gear 107 is moved to a position where it meshes with both gears 105 and 106 to establish a reverse gear train Gr. , 106 and the position where the meshing state is released.

In the sub-transmission mechanism 37, the sub-shaft 71 has a gear 7.
A synchronizing mechanism 110 for extremely low speed switching is installed to switch the connection state between 7 and the subshaft 71, and this mechanism 1
A very low speed switching shift fork 112 is engaged with the select sleeve 110 of No. 10.

Figure 6 shows the shift pattern, where N is the neutral position, is the 1st gear position, is the 2nd gear position, is the 3rd gear position, is the 4th gear position, is the 5th gear position, and R
is the reverse drive position, and an extremely low speed position SL is provided adjacent to the first speed position.

According to such a shift pattern, each of the shift forks 98, 101, 104, 109, 11
2 are arranged as shown in FIGS. 7 to 9.

That is, a shaft holder 115 is fixed to the clutch case 32 facing the transmission case 33 side, and between the shaft holder 115 and the transmission case 33 there is a shaft parallel to the input shaft 38 and the output shaft 39. 1st forkshaft 1
16 is fixed. The shaft holder 115 has
As shown in FIG. 10, an overhang part 117 is provided that overhangs from the clutch case 32 to the front wheel drive differential 4 side, and a support hole is provided in which the first fork shaft 116 is inserted and supported. 118 is provided. Furthermore, the overhang portion 117 forms a gap 119 with the peripheral edge of the deceleration ring gear 42 and extends so as to be sandwiched between the deceleration ring gear 42 and the clutch case 32.

Clutch case 32 and transmission case 3
3, second and third forkshafts 120, 121 parallel to the first forkshaft 116 are supported so that they can reciprocate within a limited range along the axial direction. The first fork shaft 116 includes a fork head 122 for switching between the first and second speeds, which integrally has a shift fork 98 for switching between the first and second speeds, and a fork head 123 for extremely low speeds.
and are slidably supported. The second fork shaft 120 also has a fork head 124 for reversing.
5th speed fork head 1 which integrally has a 3rd and 4th speed switching fork head 125 which integrally has a 3rd and 4th speed switching shift fork 101 and a 5th speed shift fork 104.
26 is slidably supported, and the third fork shaft 121 has an extremely low speed shift fork 1.
12 is fixed.

The outer surface of the first forkshaft 116 is provided with three recesses 127 spaced apart in the axial direction, corresponding to the fork heads 122 for switching between the first and second speeds.
22 includes balls 129 that are biased by the spring force of a spring 128 in a direction to fit into the recesses.
is retained. This constitutes a day tent mechanism, and the fork head 122 for switching between the first and second speeds, that is, the shift fork 98 for switching between the first and second speeds,
The select sleeve 96 is moved to the left in FIG. 2 to establish the first gear (the left position in FIG. center position in the figure) and
Position where the select sleeve 96 is moved to the right in Fig. 2 to establish the second gear (right position in Fig. 8)
You can move between the two in moderation.

Furthermore, on the outer surface of the first forkshaft 116,
Three recesses 130 are provided at intervals in the axial direction at positions corresponding to the third and fourth speed switching fork heads 125 that are slidably supported by the second forkshaft 120, and the recesses 130 are fitted into the recesses 130. A ball 131 that can be rotated is provided on the protrusion 132 of the fork head 125 for switching between the third and fourth speeds, and the ball 131 is pushed into each recess 130 by a spring (not shown).
is biased in the direction of fitting. As a result, a daytent mechanism is configured, and the fork head 125 for switching the third and fourth speeds, that is, the shift fork 101 for switching the third and fourth speeds, moves the select sleeve 99 to the second
The position for establishing 3rd gear by moving to the left in the figure (left position in Figure 8) and the select sleeve 9
9 in the center to bring it to a neutral state (8th position)
(center position in the figure) and the select sleeve 99 to the second position.
It can be moved to the right in the diagram to establish the fourth gear (the right position in Figure 8).

Moreover, the fork head 12 for switching between 3rd and 4th speeds
5 is located at a position corresponding to the very low speed fork head 123 that is slidably supported on the first fork shaft 116.
is provided with a notch 133 for causing the protrusion 132 of the fork head 125 for switching between the third and fourth speeds to protrude toward the first fork shaft 116, and the notch 133 extends in the axial direction of the first fork shaft 116. The length along is 12 fork heads for extremely low speeds.
3 and the fork head 125 for switching between the third and fourth speeds.

The fifth speed fork head 126 is integrally provided with an arm 134 that extends toward the first fork shaft 116, and a cylindrical portion 135 for penetrating the first fork shaft 116 is provided at the tip of the arm 134. provided. The arm 134 is provided with a hole 136 extending between the first and second forkshafts 116, 120.
A pair of balls 138 and 139 are inserted into the ball 36 and are urged by a spring 137 in directions away from each other. First and second forkshaft 116,1
Recesses 140, 141 for fitting the balls 138, 139 are provided on the outer surface of the ball 20, and both balls 138, 139 fit into the recesses 140, 141.
41, the position of the fifth speed fork head 126 is maintained in a moderate manner. This state is a state in which the fifth speed switching synchronization mechanism 102 is inactive, and the connection state between the fifth speed gear train G5 and the input shaft 38 is released.

With the fifth speed switching synchronization mechanism 102 inactive, the fifth speed fork head 126
is prevented from moving to the right in FIG. 8 by the side wall of the transmission case 33, and can only move to the left in FIG. 8 in order to put the fifth speed switching synchronizing mechanism 102 into operation. That is, the end of the second forkshaft 120 on the transmission case 33 side is provided with a stepped portion 142 that can come into contact with the fifth speed fork head 126, so that when the second forkshaft 120 is moved to the left, , the fifth speed fork head 126 moves to the left in FIG. 8 while compressing the spring 137 so that the ball 138 escapes from the recess 140 and rides on the outer surface of the first fork shaft 116. Due to this movement, the 5th speed switching synchronization mechanism 102 is actuated, and the 5th speed gear train G
5 is established. Moreover, when the fifth speed switching synchronizing mechanism 102 is operated, the spring 137 is compressed and exerts a large spring force, so that the second forkshaft 120 and the fifth speed fork head 12
6, and when the second forkshaft 120 moves to the right, the fork head 126 for fifth gear also moves to the right, returning to the state shown in FIG. The synchronization mechanism 102 is rendered inactive.

The reverse fork head 124 has a U-shaped tip.
An engaging arm 143 is provided which is shaped like a letter and engages with the first forkshaft 116, and this engaging arm 143 serves to prevent the second forkshaft 120 from rotating. Also fork head 1 for reversing
24 is integrally provided with an engagement pin 144 that projects, and this engagement pin 144 engages with an L-shaped through hole 145 provided in the reverse shift fork 109, as shown in FIG. be done. The reverse shift fork 109 is integrally equipped with a support shaft 146 orthogonal to the axis of the second fork shaft 120.
This support shaft 146 is inserted into a support hole 147 bored in the shaft holder 115. Moreover, the support shaft 14
A ring 148 is fitted into the part protruding from the support hole 147 of 6, and the ring 148 and the support shaft 1
By inserting the pin 149 into 46 at right angles,
A reverse shift fork 109 is rotatably supported by the shaft holder 115 around the axis of a support shaft 146. Further, the through hole 145 has a parallel portion 145a parallel to the second fork shaft 120 when the reverse shift fork 109 is in the neutral position.
and an orthogonal portion 145b orthogonal to the second forkshaft 120 are arranged in a row in an L-shape, and the second
When the forkshaft 120 is in a neutral position where it does not move to the left or right as shown in FIG.
The engagement pin 144 is located at a bent portion of the through hole 145.

Furthermore, in order to moderate the rotational movement of the reverse shift fork 109, two recesses 151 are provided adjacent to each other on the side edge of the reverse shift fork 145, and the shaft holder 115 has two recesses 151 adjacent to each other. A ball 152 that can be fitted into the ball 151 is arranged so as to be biased by a spring in the fitting direction. A spring 153 is inserted into one recess 151 as shown in FIG.
In the fitted state, the engagement pin 144 is in the through hole 145.
When the second fork shaft 120 is moved to the right in FIG. 8, that is, in the direction of the arrow 154, the reverse shift fork 109 is moved clockwise in FIG. The ball 152 is fitted into the other recess 151. This clockwise rotation of the reverse shift fork 109 moves the idle gear 107 and establishes the reverse gear train Gr.

When canceling the establishment of the reverse gear train Gr, move the second forkshaft 120 to the left and
At this time, the reverse shift fork 109 is rotated counterclockwise to be in the neutral state as shown in FIG. 11. Furthermore, when the second forkshaft 120 is moved to the left from the state shown in FIG. The reverse shift fork 109 only moves along the vehicle and does not rotate.

The very low speed fork head 123 has an engagement groove 1.
56 is provided in this engagement groove 156,
A rotation prevention rod 157 whose base end is fixed to the shaft holder 115 and extends parallel to the first forkshaft 116 is engaged, and the rotational movement of the very low speed fork head 123 around the first forkshaft 116 is prevented by the crack.

The third forkshaft 121 includes a connecting member 1
58 is fixed, and this connecting member 158 and the very low speed fork head 123 are connected by a lever 159. Lever 159 is basically L
A spherical fitting part 160 provided at one end of this lever 159 is fitted into a fitting hole 161 provided in the very low speed fork head 123. The connecting member 158 also has a connecting pin 16 that protrudes in a direction perpendicular to the third fork shaft 121.
2 is integrally provided, and this connecting pin 16
2 is fitted with a U-shaped fitting portion 163 provided at the other end of the lever 159. Moreover, lever 159
The bent portion 159a is connected to a pivot pin 164 orthogonal to the first and third fork shafts 116, 121.
is supported by.

With particular attention to FIG.
4, G5, and Gr, that is, between the third speed gear train G3 and the fourth speed gear train G4, the pivot pin 164 is fixed to the side wall of the transmission case 33. That is, the pivot pin 164 has a large-diameter head 165, a male threaded portion 166 screwed into the side wall of the mission case 33, and a bent portion 1 of the lever 159, in order from one end thereof.
A small-diameter pivot portion 167 is provided to be inserted into a pivot hole 168 drilled in 59a, and is screwed onto the side wall of the mission case 33 from the outside.

By thus pivoting the lever 159 at its intermediate bent portion by the pivot pin 164, the lever 159 performs a seesaw action. That is, when the very low speed fork head 123 is moved to the left in FIG.
moves to the right, and the select sleeve 111 moves to the second
Moving to the right in the figure, the reduction gear train 78 of the sub-transmission mechanism 37 is established. When the very low speed fork head 123 is moved to the right from this state, the connecting member 158, the third fork shaft 121, and the very low speed shift fork 109 are moved to the left, and the select sleeve 111 is moved to the left in FIG. Go to
The connection state between the reduction gear train 78 and the subshaft 71 is released.

In order to move left and right to the third forkshaft 121 in a controlled manner, a pair of depressions are provided at an interval in the axial direction on the outer surface of the end of the third forkshaft 121 on the transmission case 33 side. 169 are provided, and balls 170 that fit into these recesses 169 are biased by springs 171 in the direction of fitting into each recess 169.

As shown in FIG. 8, when the ball 170 is fitted into the right recess 169, the very low speed shift fork 109 is in a state where the very low speed switching synchronization mechanism 110 is inactive, When the third forkshaft 121 is moved to the right from this state and the ball 170 is fitted into the left recess 169, the very low speed switching synchronization mechanism 110 is activated.

The very low speed fork head 123, the first and second speed switching fork heads 122, the third and fourth speed switching fork heads 125, and the reverse fork head 124 each have a U-shaped locking part 172 for very low speeds, a first , a locking part 173 for switching to 2nd speed, a locking part 174 for switching to 3rd and 4th speeds, and a locking part 175 for switching to 5th speed and reverse, which are connected from the first forkshaft 116 to the second forkshaft 116. They are arranged in this order toward the shaft 120 side.

Referring to FIGS. 12 and 13 together, a cover 179 is fixed to the upper part of the clutch case 32 to define an operating chamber 178 that communicates with the inside of the transmission case 33. Selection of locking parts 172, 173, 174, 175,
Select and shift mechanism 180 for operation
will be placed.

To explain this select and shift mechanism 180 in detail, a shift piece shaft 181 extending in a direction orthogonal to each of the fork shafts 116, 120, 121 is fixedly disposed on the cover 179. A shift piece 183 is slidably and rotatably supported on this shift piece shaft 181 and is integrally provided with an engaging arm 182 that can selectively engage each of the locking portions 172, 173, 174, and 175. . This shift piece 183 has a rotation engagement groove 184 extending parallel to the shift piece shaft 181;
A sliding engagement groove 185 extending perpendicularly to the shift piece shaft 181 is provided.

A spherical end 188 of a shift arm 187 rotatably supported by the cover 179 via a shift shaft 186 is slidably fitted into the rotation engagement groove 184 . In addition, the sliding engagement groove 185 has a cover 1.
A pin-shaped end 191 of a select arm 190 rotatably supported by a select shaft 189 at
are slidably engaged. The shift shaft 186 and the select shaft 189 extend in a direction perpendicular to the shift piece shaft 181 and protrude from the cover 179, and the shift arm 187 and the select arm 190 are arranged substantially orthogonally in the working chamber 178 so that the shift shaft 189 extends in a direction perpendicular to the shift piece shaft 181. 186 and select axis 18
Fixed to 9. Further, on the outside of the cover 179, a shift lever 192 is fixed to the shift shaft 186, and a select lever 193 is fixed to the select shaft 189.

A shift wire 194 is attached to the shift lever 192.
The terminal end of the select wire 195 is connected to the select lever 193. These wires 194 and 195 perform a push-pull operation in response to the operation of a change lever (not shown), and the selection wire 195 performs a push-pull operation in response to displacing the change lever at the neutral position N. , the shift wire 194 moves the change lever to each shift position SL,...
, V, R, push/pull operation is performed.

The shift piece shaft 181 has the shift piece 18
U-shaped interlock plate 19 sandwiching 3.
6 and is slidably arranged. This interlock plate 196 is provided with a long groove 197 extending parallel to the shift piece shaft 181, and when a pin member 198 screwed onto the cover 179 engages with the long groove 197, the rotational movement of the interlock plate 196 is controlled. thwarted.

There are three depressions 20 at the tip of the shift arm 187.
1 are provided, and balls 202 that can fit into the recesses 201 are biased by a spring 203 housed within the cover 179 in the direction of fitting into each recess 201. As a result, the shift arm 187 can be rotated between three positions. Moreover, these three positions are determined by shift piece 1 according to the shift pattern shown in FIG.
83, each locking portion 172, 173, 174, 1
This corresponds to the position for shifting 75.

Each locking portion 1 is provided at the tip of the select arm 190.
A recess 204 extending in an arc shape centered on the shift shaft 186 is provided with a length corresponding to moving the shift piece 183 to select 72, 173, 174, 175. A spring 205 housed in the ball 179 causes the ball 106 to resiliently slide into contact. Further, an arm portion 207 is integrally provided on the select arm 190, and both ends of a torsion spring 208 that surrounds the select shaft 189 extend to both ends of the arm portion 207. Both ends of the torsion spring 208 are engaged with locking pins 209 protruding from the cover 179, and the select arm 190 rotates to select a gear position by the rotation of the select shaft 189. At times, it exerts a spring force in the direction of returning the select arm 190 to its original position, and serves to give the driver a sense of operation when operating the change lever.

At a position adjacent to the select shaft 189 on the side where the shift piece 183 engages with the very low speed locking part 172, a very low speed interlock plate 210 is connected to the cover 1 via a rotating shaft 211 parallel to the select shaft 189.
79 so as to be rotatable. This very low speed interlock plate 210 is rotatable between a position where it blocks movement of the select shaft 189 until selecting very low speed and a position where it is allowed, and moderates the rotational movement between these positions. A pair of recesses 212 are provided for this purpose. Also, on the cover 179 side, there are balls (not shown) that can fit into those recesses 212.
is biased by a spring in the direction of fitting into the recess 212,
Placed.

On the other hand, the select arm 190 is provided with a protrusion 213, and an extremely low speed interlock plate 210 is provided.
When the protrusion 213 is rotated to a position that prevents selection of extremely low speed, the protrusion 213 comes into contact with the extremely low speed interlock plate 210, and further rotation is prevented. As a result, the shift piece 183 becomes unable to engage with the very low speed locking portion 172, and selection of the very low speed is prevented.

The rotation shaft 211 protrudes from the cover 179, and the rotation shaft 211 and the gear clutch mechanism 55 in the transfer 5 are connected to operate together. That is, as shown in FIG. 7, the swing shaft 61 of the gear clutch mechanism 55 is connected to the clutch case 32.
A connecting lever 214 is provided to protrude outward in the radial direction at the projecting end 61a of the swing shaft 61, and a connecting lever 214 is provided to project outward in the radial direction at the projecting end of the rotation shaft 211. connection lever 215
and are interconnected via a connecting rod 216. Moreover, the connection mode is the gear clutch mechanism 5.
5 is in the cut-off state, the extremely low speed interlock plate 210 is rotated to a position where it can come into contact with the protrusion 213 of the select shaft 189, thereby blocking selection of the extremely low speed.

In the shift piece shaft 181, a step portion 217 facing the front end side is provided at the front end portion along the moving direction of the shift piece 183 toward the extremely low speed side, and a shift portion on the front end side of the step portion 217 is provided. A plate-shaped abutting collar 218 that can abut against the step portion 217 is slidably disposed on the piece shaft 181 . A malfunction prevention spring 219 is interposed between the abutting collar 218 and the cover 179, and the spring force of the spring 219 urges the abutting collar 218 toward the stepped portion 217.

The contact flange 218 is capable of contacting an interlock plate 196 that moves on the shift piece shaft 191 together with the shift piece 183, and when the abutment flange 218 is in contact with the stepped portion 217, the shift piece 183 When the interlock plate 196 is in the position to select the first speed or the second speed, the contact flange 218
It is set so that it comes into contact with. Therefore, when moving the shift piece 183 from the first speed or second speed selection position to the very low speed selection position, the abutment collar 218 is pressed and moved against the spring force of the malfunction prevention spring 219. It is necessary to do so.

A breather hole 220 is provided in the shift shaft 186 between the working chamber 178 and the outside, and a conduit 222 is further connected to a small diameter connecting pipe 221 connected to the outer end of the breather hole 220. .

Next, to explain the operation of this embodiment, by operating the change lever according to the shift pattern shown in FIG.
95 and the shift wire 194 perform a push-pull operation, and the select and shift mechanism 180 operates accordingly to establish a desired gear train in the transmission 3. That is, when shifting to the first gear, the shift piece 183 flies over the shift piece shaft 181 and engages with the first and second gear switching locking part 173, and then the shift piece 183 moves to the clock position shown in FIG. By rotating in the direction, the first
The second speed switching locking portion 173, that is, the first and second speed switching fork heads 122 and the first and second speed switching shift forks 98 move to the left in FIG. 8, and the first speed gear train G1 is established. To shift to the second gear, the shift piece 183 may be rotated counterclockwise in FIG. 13, and the shift fork 98 for switching between the first and second gears will move to the right in FIG.
The second speed gear train G2 is established.

When selecting the third and fourth gears, the shift piece 183 rotates at a position corresponding to the third and fourth gear switching locking portions 174.
Third speed gear train G3 and fourth speed gear train G4 are selectively established. In addition, when selecting the fifth gear and the reverse gear, the shift piece 183 selects the fifth gear and the reverse gear.
By rotating at a position corresponding to the backward switching locking portion 175, the fifth speed gear train G5 and the reverse gear train Gr are selectively established.

When selecting extremely low speed, shift piece 183
engages with the very low speed locking part 172 and rotates clockwise in FIG. 13, so that the very low speed fork head 123 slides to the left in FIG. However, lever 15
9 and the connecting member 158, the third forkshaft 121 and the very low speed forkshaft 112 are moved to the right, and the sleeve 11
1 moves to the right side in FIG. 2 and the reduction gear train 78 is established. Thereby, the driving force of the input shaft 38 is transmitted to the output shaft 39 via the sub-transmission mechanism 37, and the output of the output shaft 39 is transmitted to the transfer 5 at extremely low speed.

Moreover, when the gear clutch mechanism 55 is in the disconnected state, the select/shift mechanism 180 is in a position where the protrusion 213 of the select arm 190 can engage with the very low speed interlock plate 210, as shown by the solid line in FIG. Yes, select axis 18
9 connects the shift piece 183 to the very low speed locking part 172
It is prevented from rotating to the position where it is engaged with. Therefore, extremely low speed can be selected only in all-wheel drive with the gear clutch mechanism 55 in the connected state.

C. Effects of the Invention According to the present invention, a protrusion is provided on the select shaft or the select arm, and the very low speed interlock plate that can come into contact with the protrusion is shifted to the position for selecting the reduction gear train of the sub-transmission mechanism. With an extremely simple configuration in which the select shaft is movable between a position that prevents rotation in the direction of moving the piece and a position that allows the rotation, extremely low speed selection is possible. It is possible to make it impossible.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a schematic diagram of the entire transmission system of a vehicle equipped with the transmission of the present invention, FIG. 2 is a longitudinal developed view of the transmission including the transmission, and FIG. 4 is an enlarged longitudinal sectional view of the auxiliary transmission mechanism, FIG. 4 is a sectional view taken along the line -- in FIG. 3, FIG. Fig. 7 is a cross-sectional side view taken in the direction of the arrow in Fig. 2, Fig. 8 is a plan view showing the arrangement of each shift fork, Fig. 9 is a perspective view showing the operating system of each shift fork, and Fig. 10 is a clutch of the shaft holder. Vertical side view showing the state of attachment to the case, No. 11
12 is a cutaway plan view of the select and shift mechanism, and FIG. 13 is a sectional view taken along the line -- in FIG. 12. 3...Transmission, 36...Main transmission mechanism, 37...
Sub-transmission mechanism, 78... Reduction gear train, 181... Shift piece shaft, 183... Shift piece, 189
...Select axis, 190...Select arm, 2
10... Very low speed interlock plate, 212... Protrusion, G1 to G5, Gr... Gear train.

Claims (1)

[Claims] 1. A main transmission mechanism having a gear train with a plurality of gears that can be selectively established, and a sub-transmission mechanism having a reduction gear train for achieving an extremely low speed lower than the lowest speed of the main transmission mechanism, A shift piece for selecting the establishment of each gear train is slidably supported on a shift piece shaft, and a select shaft rotatable around an axis perpendicular to the shift piece shaft includes a select arm that engages with the shift piece. are integrated,
The selected position of each gear train by the shift piece is
In the vehicle transmission, the position where each gear train of the main transmission mechanism can be selected and the position where the reduction gear train of the auxiliary transmission mechanism can be selected are shifted in the axial direction of the shift piece shaft. A protrusion is provided on the select shaft or the select arm, and an extremely low speed interlock plate that can come into contact with the protrusion controls the rotation of the select shaft in the direction of moving the shift piece to the position where the reduction gear train is selected. The blocking position and
A vehicle transmission characterized in that it is disposed so as to be movable between positions that allow the rotation.