JP3507446B2 - Travel equipment for work vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling device for a work vehicle such as a combine, and more particularly to a right and left traveling drive shaft for decelerating the rotation of a main drive shaft and transmitting it to the left and right traveling drive shafts. The present invention relates to a traveling device provided with a planetary gear device. BACKGROUND OF THE INVENTION Between a main drive shaft driven by a speed change via an input gear and left and right traveling drive shafts, the rotation of the main drive shaft is greatly reduced and transmitted to the left and right travel drive shafts. The left and right planetary gear devices are provided with a planetary gear device in which each sun gear is fixed to a main drive shaft. They are fixed to the main drive shaft using separate means. The present invention seeks to simplify the structure of a traveling device of the above type by fixing an input gear and left and right sun gears on a main drive shaft by means of a single process. . [0004] A traveling device for a work vehicle according to the present invention comprises:
It is configured as follows. First reversible continuously variable transmission
The input gear (63) driven to change the speed by the device (28)
The main drive shaft (40) fitted, and the main drive shaft (40)
Left and right running concentrically with the main drive shaft
The row drive shaft (37L, 37R) and the main drive shaft (4
0), the left and right traveling drive shafts (37L, 37L,
37R) for transmission to the left and right planetary gear units (4
1L, 41R), a traveling device of a work vehicle comprising:
Each of the planetary gear units (41L, 41R) is a main drive.
A sun gear (67) fixedly mounted on a driving shaft (40);
It is arranged on the outer peripheral side of the sun gear ( 67), and the internal gear (6)
8) A ring member (71) forming a left and right traveling drive
Left and right carriers (6) fixed to shafts (37L, 37R)
9, 69) and is rotatably supported by the sun gear (67) and
And a plurality of idlers meshed with the inner toothed wheel (68).
A star gear (70), wherein the main drive shaft (40) is
Of each of the carriers (69, 69),
On each of the left and right carriers (69, 69),
Gears (73, 73) that are rotationally driven in the
The gear (73, 73) is a second reversible continuously variable transmission.
(32) driven by the left and right planetary gear units (41
L, 41R) to give additional rotations in opposite directions
Then, for the left and right traveling drive shafts (37L, 37R)
Turn the vehicle by giving a difference in the number of revolutions, and the left and right planetary gears
The left and right sun gears (6) in the devices (41L, 41R)
7) are integrated with each other on the outer peripheral surface of the main drive shaft (40).
When it is constituted by the tooth profile (40a) formed continuously with
In addition, the input gear (63) is formed by using the tooth profile (40a).
Work vehicle fitted on the main drive shaft
Traveling device . According to the present invention, the tooth profile (40a) constituting the left and right sun gears (67) is formed integrally with the main drive shaft (40), and the tooth profile (40a) is used. Since the input gear (63) is fitted to the main drive shaft (40), the left and right sun gears (67) together with the support means for the input gear (63) on the main drive shaft (40) Provided by a single machining of the main drive shaft, the structure of the traveling device to obtain a great reduction between the main drive shaft and the left and right traveling drive shafts and to provide the left and right planetary gear units (41L, 41R) To be simple. In one embodiment of the present invention, a reversible continuously variable transmission (28) is provided, and the reversible continuously variable transmission is interlocked with the input gear (63) so as to drive the input gear at a variable speed. you. Preferred as the reversible continuously variable transmission is a hydraulic transmission device including a variable displacement hydraulic pump and a constant displacement hydraulic motor, and the main drive shaft is controlled by the reversible continuously variable transmission or the hydraulic transmission device. Variable speed drive is possible in the forward and reverse steps. In the structure in which the stepped transmission is provided, the speed of the reversible continuously variable transmission or the hydraulic transmission is controlled in a relatively high speed range in which the output rotation is stable. The vehicle speed control can be performed so as to be divided into a road traveling speed change range in which rotation is given and a work speed change range in which work is given at relatively low speed. Also the gear
(73, 73) is the second reversible continuously variable transmission (32).
The planetary gear units (41L, 41L)
R), applying additional rotations in opposite directions to each other,
Between the left and right traveling drive shafts (37L, 37R)
To turn the vehicle . FIG. 2 shows a combine equipped with an embodiment of a traveling device according to the present invention. The illustrated combine is driven and driven by the right and left crawlers 1 as usual, cuts the planted grain culm in the cutting section 2 in front of the machine body, and threshes the cut culm in the threshing section 3 on the machine body. It is stored in the grain tank 4 on the fuselage, and the waste straw is a waste straw processing device at the rear of the fuselage (bundling, bundling, cutter device or switchable combination thereof).
5 is performed. The engine 6 is installed closer to the body, and a transmission 7 that receives input power from the engine is disposed at a lower front position of the engine 6. A control unit 9 having a seat 8 is disposed on the upper front side of the engine 6. The steering section 9 includes a steering wheel 10 for operating the vehicle, a main shift lever 11 and a sub shift lever 12 for controlling a vehicle speed, a parking brake lever 13, and the like. In FIG. 2, reference numeral 14 denotes an axle equipped with crawler drive wheels 15, 16 denotes a cutting blade, and 17 denotes a grain-lifting device for carrying out grains from the grain tank 4. FIG. 3 shows the appearance of the transmission 7, and FIGS. 4 and 5 show the main internal structure thereof. As shown in these figures, the transmission 7 includes a transmission case 19 including left and right case halves 19a and 19b on a lower side, and a substantially L-shaped thick plate protruding upward from an upper side surface of the right case half 19b. A member 20 is mounted, and a rectangular housing 21 is provided on the upper half of the left side surface of the plate member 20, and an L extending over the entire side surface is provided on the right side surface.
It has a casing structure in which letter-shaped housings 22 are mounted. As shown in FIG.
An input shaft 23 is provided through the plate 22 and the plate member 20, and an input pulley 24 is fitted to the input shaft 23 outside the housing 21 as shown in FIG. The input transmission to the input shaft 23 is performed by 25. As shown in FIGS. 3 and 4, the left and right axles 14 project from the left and right case halves 19a and 19b through the left and right axle cases 26 attached to the case halves. As shown in FIGS. 4 and 5, hydraulic pumps 29 and 33 having the input shaft 23 as a pump shaft are mounted on the left and right surfaces of the upper half of the plate member 20 and installed in the housings 21 and 22, respectively. Hydraulic motors 30, 34 having output shafts 31, 35 protruding into the transmission case 19,
The housing 2 is mounted on the right side of the lower half of the plate member 20.
2 Each of the hydraulic pumps 29 and 33 is a swash plate 2
The variable displacement type is configured so that the oil discharge amount and the discharge direction can be changed by changing and adjusting the inclination angles of 9a and 33a.
Control arm 2 for tilting operation of swash plates 29a and 33a
9b and 33b, as shown in FIG.
2 attached to the swash plate support shaft. A first reversible continuously variable transmission 28 shown in FIG. 1 is constituted by fluidly connecting a hydraulic pump 29 and a constant displacement hydraulic motor 30, and a hydraulic pump 33 and a constant displacement hydraulic motor 34 are connected to each other. Are fluidly connected to form a second reversible continuously variable transmission 32 shown in FIG. In addition, an oil passage connecting each hydraulic pump 29, 33 and each hydraulic motor 30, 34, and each reversible stepless variable
The valves attached to the speed devices 28 and 32 are plate members 2
0 is provided. [0010] As shown in FIGS.
The left and right traveling drive shafts 37L and 37R are provided concentrically with each other at a lower position in the inside 9.
L and 37R are connected to the left and right axles 14 by left and right gears 38 and 39, respectively. A main drive shaft 40 concentrically arranged with the left and right traveling drive shafts 37L and 37R is arranged, and the rotation of the main drive shaft 40 is reduced by the left and right planetary gear units 41L and 41R. Is transmitted to the traveling drive shafts 37L and 37R. The first reversible continuously variable transmission 28 transmits power from the output shaft 31 to the left and right traveling drive shafts 37L and 37R via the main drive shaft 40 and the left and right planetary gear units 41L and 41R. And the second reversible continuously variable transmission 32 is selectively driven by the output shaft 35 with respect to the left and right traveling drive shafts 37L and 37R. By using the 41R, additional rotations in directions opposite to each other are given, so that the left and right traveling drive shafts 37
L and 37R are provided for turning the vehicle by giving a rotation speed difference. First reversible continuously variable transmission 28
The control arm 29b for operating the pump swash plate is operated by the main shift lever 11 shown in FIG. 2, and the control arm 33b for operating the pump swash plate of the second reversible continuously variable transmission 32 is shown in FIG. The steering wheel 1 shown in FIG.
0 is operated. The output shaft 3 of the first reversible continuously variable transmission 28
The transmission mechanism between the shaft 1 and the main drive shaft 40 is shown in FIGS.
It has an intermediate shaft 44 and an auxiliary transmission shaft 45. Clutch shaft 43
Is connected to the output shaft 31 by meshing an output gear 46 on the output shaft 31 with a gear 47 on the clutch shaft 43. A gear 48 is loosely installed on the clutch shaft 43 and meshed with a gear 49 fixedly installed on the intermediate shaft 44, and a clutch 50 for selectively coupling the gear 48 to the clutch shaft 43 is provided. It is installed on the clutch shaft 43. The clutch 50 frictionally engages a plurality of friction elements, each of which is slidably supported by a clutch cylinder 50a fixedly mounted on a clutch shaft 43 and a boss of a gear 48, by the pressing action of a piston 50b. It is configured as a hydraulic multi-plate type that obtains clutch engagement. A switching valve (not shown) for controlling the on / off of the clutch 50 is connected to the clutch pedal 100 shown in FIG. 2 provided in the step of the vehicle so that when the pedal 100 is depressed, the clutch 50 is disengaged. It is. A mechanical auxiliary transmission 52 is disposed between the intermediate shaft 44 and the auxiliary transmission shaft 45. This auxiliary transmission 52
Is a shift gear 5 installed only on the intermediate shaft 44 so as to slide only.
3. Two gears 54 and 5 loosely fitted on the intermediate shaft 44
5, a gear 56 fixedly mounted on the auxiliary transmission shaft 45 and capable of meshing with the shift gear 53, and two gears 5 fixedly installed on the auxiliary transmission shaft 45 and engaged with the gears 54 and 55.
7, 58. The shift gear 53 is configured such that the clutch pawls provided on both sides thereof are meshed with the clutch pawls provided on the gears 54 and 55, and the gears 54 and 55 can be selectively coupled to the intermediate shaft 44. . As described above, the auxiliary transmission device 52 drives the auxiliary transmission shaft 45 by the intermediate shaft 44 via the gears 54 and 57, the high-speed gear (road running gear), and the intermediate transmission 44 via the gears 53 and 56 (the medium-speed gear). It can be switched to three speeds, a dry speed (a dry work speed) and a low speed (a wet work speed) driven through the gears 55 and 58. As shown in FIG. 7, there is provided a shift fork 60 that is slid by a rotation operation shaft 59 penetrating the side wall of the transmission case 19 to shift the shift gear 53, and a shift arm attached to an outer end of the operation shaft 59. Reference numeral 61 is connected to the auxiliary transmission lever 12 shown in FIG. As shown in FIGS. 1 and 4, the gear 58 of the auxiliary transmission shaft 45 is meshed with a large-diameter input gear 63 fixed and installed on the main drive shaft 40. One end of the auxiliary transmission shaft 45 protrudes into a brake case formed on the outer surface of the left case half 19a of the transmission case 19, and a parking brake 64 for braking the auxiliary transmission shaft 45 is provided in the brake case. It is provided. The brake arm 65 at the outer end of the camshaft 64a for braking the brake 64, which is constituted by a friction multi-plate type and is operated by a cam mechanism including a camshaft 64a and a ball 64b, is provided with the parking brake lever shown in FIG. 13. Therefore, the main drive shaft 40 is controlled in three steps by the first reversible reversing continuously variable transmission 28 and the sub transmission lever 12 whose output speed is continuously and continuously controlled, including forward and reverse rotation, by the main transmission lever 11. The main drive shaft 40 and the left and right traveling drive shafts 3
Left and right planetary gear units 41L connecting between 7L and 37R,
41R is configured as follows. That is, as shown in FIG. 8, which is an enlarged view of FIGS. 1, 4 and a part of FIG.
1R is, as usual, a sun gear 67, an internal toothed wheel 68 provided at an outer peripheral position of the sun gear 67, and a sun gear 67 and an internal toothed wheel 68 rotatably supported by a carrier 69. A plurality of (three) planetary gears 70 are engaged with each other. First, the left and right sun gears 67 are integrally formed on the outer peripheral surface of the main drive shaft 40 as shown in FIG. 40
a, and the internal teeth 67a corresponding to the tooth profile 40a
Is formed on the inner peripheral surface of the center hole of the input gear 63, and the input gear 63 is fitted on the main drive shaft 40 by meshing the internal teeth 67a with the tooth form 40a. The axial position of the input gear 63 is regulated by a pair of retaining rings 75 on both sides fitted to the main drive shaft 40. The left and right carriers 69 are fixed to the left and right traveling drive shafts 37L and 37R by spline fitting, and a ring 69a arranged on the input gear 63 side is connected to the carrier 69 main body via a spacer 69b and a bolt 69c. Then, a pin 69d which is retained by the ring 69a is provided, and the planetary gear 70 is provided on the pin 69d so as to freely rotate. The internal toothed wheel 68 is provided with a sun gear 67 as usual.
The left and right rings 71 are formed on the inner peripheral surface of the ring 71 disposed on the outer peripheral side of the right and left traveling drive shafts 37L, 37L.
Left and right gears 73 which are loosely fitted on the boss portion of the carrier 69 via a pair of ball bearings 72 on the 7R, internal teeth 71a formed on the inner peripheral surface of the ring 71, and boss portions of the gear 73. The external teeth 73a are supported so as not to rotate relative to each other by meshing with each other. Then, the pin 74 inserted into the ring 71 is brought into contact with the side faces of the internal teeth 71a and the external teeth 73a to prevent the ring 71 from being pulled out.
Is supported on the gear 73 so as to be movable in the radial direction. Output shaft 3 of second reversible continuously variable transmission 32
The additional rotation transmitting mechanism shown in FIGS. 1, 5 and 6 is provided between the ring 5 and the rings 71 of the left and right planetary gear units 41L and 41R. That is, an intermediate shaft 77 and a lock shaft 78 which are parallel to the output shaft 35 are provided, and the output shaft 35 and the intermediate shaft 77 are connected by gears 79 and 80 by a reduction mechanism.
And the lock shaft 78 are connected by gears 81 and 82 reduction mechanism. The left and right rings 71 are connected between the lock shaft 78 and the left and right rings 71 using the right and left gears 73 so that the right and left rings 71 can be rotated at a constant speed in opposite directions by the lock shaft 78. That is, a gear 83 integrally formed with the gear 82 and fitted to the lock shaft 78 meshes with the gear 73 that rotates integrally with the left ring 71, and a gear 73 that integrally rotates with the right ring 71. The gear 84 fitted to the lock shaft 78 is connected to the case half 19b.
The gears are meshed via an idler gear 86 on an idler shaft 85 that is supported by the gears, and the reduction ratios of the left gears 83, 73 and the reduction gears of the right gears 84, 86, 73 are set to be equal. Therefore, the second reversible continuously variable transmission 3
2 between the output shaft 35 and the left and right rings 71 of the left and right planetary gear units 41L and 41R, the gear transmission 87 (FIGS. 1 and 5) rotates the output shaft 35 relative to the left and right rings 71. The rotation is transmitted in the opposite direction. When the second reversible continuously variable transmission 32 or its hydraulic pump 33 is in the neutral state and the output shaft 35 is not rotated, the left and right rings 71 try to rotate and displace in the same direction at the same speed. The rotation displacement is the lock shaft 7
8, the lock shaft 78 does not rotate in any direction, so that the lock shaft 78 locks the left and right rings 71 so that they cannot rotate. In order to drive the reaper 2 shown in FIG. 2, a PTO shaft 89 is provided as shown in FIGS. PTO via one-way clutch 90
A pulley 91 is provided, and a belt 93 is wound between the pulley 91 and the input pulley 92 of the reaper 2. Then, as shown in FIGS.
An intermediate shaft 94 is provided between the output shaft 31 and the PTO shaft 89 of the reversible continuously variable transmission 28, and the output gear 46 on the output shaft 31 is provided.
Is provided on the intermediate shaft 94, and the intermediate shaft 94 and the PTO shaft 89 are speed-reduced by gears 96 and 97. The one-way clutch 90 is engaged only when the output shaft 31 is rotated in the vehicle forward direction, and connects the pulley 91 to the PTO shaft 89. A driving force is further transmitted from the reaping unit 2 in FIG. 2 to the threshing unit 3, the straw processing device 5, and the like. The above-described arrangement of the shaft and the gears in the up-down direction and the front-rear direction is shown in FIG. In the combine shown in FIG. 2, depending on the traveling conditions, the sub-transmission lever 12 changes the sub-transmission 52 shown in FIGS. 1 and 4 to a high speed when traveling on the road, a medium speed during dry field work, and a low speed during wet field work. Selectively set, and the main reversing lever 11 is used for the first reversible stepless stepless drive shown in FIGS.
By operating the pump swash plate 29a of the transmission 28 to continuously change the vehicle speed including the control of the traveling direction, the vehicle can be driven. Pump swash plate 33a operating in the second reversible CVT 32 at the time of straight vehicle shown in FIGS. 1 and 5 by the steering wheel 10 is not performed, the reversible CVT 3
2 is maintained in a neutral state. At this time, the rings 71 of the left and right planetary gear units 41L and 41R are restrained by the lock shaft 78 from being rotationally displaceable as described above. FIGS. 10L and 10R schematically show left and right planetary gear units 41L and 41R. First reversible
When the hydraulic motor 30 of the continuously variable transmission 28 is rotating forward, the sun gear 67 rotates in the direction of arrow A, whereby each planetary gear 70 rotates in the direction of arrow B while rotating in the direction of arrow B in FIG. Then, the carrier 69 revolves while rotating the carrier 69 (not shown). In this case, the carrier 69 and each traveling drive shaft 3
The number of rotations R given to 7L and 37R is as follows, assuming that the number of rotations of the sun gear 67 is 1, the number of teeth of the sun gear 67 is N1, and the number of teeth of the internal toothed wheel 68 is N2: R = N1 / (N1 + N2) By setting the number of teeth N2 appropriately, a large deceleration can be obtained. When the hydraulic motor 30 rotates in the reverse direction, only the rotation direction is reversed, and the situation is the same as described above. While the vehicle is moving forward, the steering wheel 10
Is rotated to rotate the hydraulic motor 34 of the second reversible continuously variable transmission 32 in the forward direction by the gear transmission 87 shown in FIGS. The ring 71 of the planetary gear device 41L is given rotation in the direction of arrow D1, and the right gears 84, 86, 73
The rotation in the direction of arrow D2 is given to the ring 71 of the right planetary gear set 41R via the row. Depending on the rotation of the left ring 71 in the direction of the arrow D1, the rotation speed of the planetary gear 70 in the direction of the arrow C, and therefore the rotation speed of the left carrier 69 and the traveling drive shaft 37L, is reduced by the rotation speed. Depending on the rotation of the ring 71 in the direction of the arrow D2, the number of rotations of the planetary gear 70 in the direction of the arrow C by the rotation speed, and therefore the right carrier 69 and the traveling drive shaft 37R.
Is increased. Therefore, the vehicle is turned to the left, and the turning radius can be freely selected by adjusting the operation amount of the steering wheel 10 and controlling the rotation speed of the hydraulic motor 34. A right turn while the vehicle is moving forward and a left or right turn while the vehicle is moving backward can be obtained in a similar manner. As described above, the ring 71, which is supported by the gear 73 so as to be relatively non-rotatable, is prevented from coming off in the axial direction by the pin 74 shown in FIG. 8, and the ring 71 is movably supported in the radial direction. It is prevented that any one of the planetary gears 70 meshes eccentrically with the internal gear 68 by the escape of the ring 71 in the radial direction, and the power is equally distributed to the plurality of planetary gears 70 so that Damage and the generation of vibration and noise in the planetary gear set are eliminated. The cutting unit 2 receives the rotation synchronized with the forward speed of the vehicle by the PTO shaft 89 while the cutting clutch (not shown) is engaged, cuts the culm row in the field, and sends it to the threshing unit 3. Here, when the end of the culm row has been cut, the operator depresses the clutch pedal 100 to release the clutch 5.
Even if the vehicle is temporarily stopped after turning off 0, the rotational output of the output shaft 31 in the forward direction is continued, and the PTO shaft 89 continues to drive the cutting unit 2, so that the harvested culm can always be sent to the threshing unit. it can. Then, the operator releases the depressed clutch pedal 100 to connect the clutch 50, and at the same time, turns the vehicle by rotating the steering wheel 10 by a predetermined amount to turn the reaping unit 2 to the adjacent uncut side culm. Align to column. FIG. 12 shows another example of a support mechanism of the ring 71 for distributing power and the like in the planetary gear device 41L (the same applies to 41R).
L has a boss of the carrier 69 and a pair of ball bearings 7
In a structure in which the ring 71 is supported by the gear 73 supported through the pin 2, a pin 174 inserted into the ring 71 is fitted into a hole of the boss of the gear 73. In this embodiment, the ring 71 can be displaced radially on the pin 174 while the axial displacement of the ring 71 is directly prevented by the pin 174. FIG. 13 shows another modification, in which a gear 73 is formed integrally with the outer peripheral surface of a ring 71 and
On the inner peripheral side via the boss portion of the carrier 69 and the ball bearings 172 on the respective traveling drive shafts 37L, 37R, and on the outer peripheral side via the ball bearing 99 to the transmission case 19, so that the gear 73 is supported. The ring 71 provided is stably supported. Also in this embodiment, the ring 71 and the gear 73 may be formed separately, and the ring 71 may be supported by the gear 73 so as to be displaceable in the radial direction. In the above embodiment, the first and second reversible rotationless
Each as variable transmission, a pump swash plate 29a, 33a
Reversing continuously variable transmission 2 that obtains a continuously variable transmission by controlling the inclination of the vehicle
8, 32, but the present invention is of course
One person or both of the reversible continuously variable transmission, it is also possible to implement a reversible CVT friction mechanical such as described above.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a mechanism diagram showing a transmission mechanism in a combine equipped with an embodiment of the present invention. FIG. 2 is a schematic side view of the combine. FIG. 3 is a schematic perspective view showing an appearance of a transmission provided in the combine. FIG. 4 is a partially developed longitudinal rear view of the transmission. FIG. 5 is a partially cutaway, partially developed longitudinal rear view along another cut surface of the transmission. FIG. 6 is a longitudinal sectional view of a part of the transmission. FIG. 7 is a side view showing a shaft and gear arrangement in the transmission. FIG. 8 is an enlarged view showing a part of FIG. 4 in an enlarged manner. 9 is a schematic exploded perspective view of a main drive shaft and an input gear shown in FIGS. FIG. 10 is a schematic diagram of a planetary gear device for explaining an operation. FIG. 11 is a longitudinal sectional view of a part of the transmission. FIG. 12 is a longitudinal sectional view showing a partial modification. FIG. 13 is a longitudinal sectional view showing another modification. [Description of References] 7 Transmission 28 First reversible continuously variable transmission 31 Output shaft 37L, 37R Travel drive shaft 40 Main drive shaft 40a Tooth profile 41L, 41R Planetary gear device 52 Sub-transmission device 63 Input gear 67 Sun gear 68 Toothed wheel 70 planetary gear 71 ring

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-296631 (JP, A) JP-A-7-96855 (JP, A) JP-A-8-310434 (JP, A) 12616 (JP, Y1) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 1/28 B60K 17/10 F16H 47/04 F16H 57/08

Claims (1)

(57) Claims 1. A first reversible continuously variable transmission (28).
A main drive shaft (40) fitted with an input gear (63) that is driven by variable speed driving, left and right traveling drives disposed concentrically with the main drive shaft, disposed on the left and right sides of the main drive shaft (40); The left and right planetary gear units (41L, 41R) for reducing the rotation of the shafts (37L, 37R) and the main drive shaft (40) and transmitting the reduced rotation to the left and right traveling drive shafts (37L, 37R). The planetary gear device (41L, 41R) includes a sun gear (67) fixedly installed on a main drive shaft (40), and an outer periphery of the sun gear (67). Side, the internal toothed wheel (6
8), the left and right carriers (6) fixed to the left and right traveling drive shafts (37L, 37R).
9, 69) rotatably supported on the main drive shaft (40) , comprising a plurality of planetary gears (70) rotatably supported by the sun gear (67) and the internal gear (68 ). Is the left and right carriers (69, 69)
Are supported by each of the left and right carriers (69, 69).
Gears (73, 73) that are rotationally driven in different directions
The gears (73, 73) are provided with a second reversible continuously variable transmission (3).
2) driven by the left and right planetary gear units (41L,
41R), applying additional rotations in opposite directions to each other,
It rotates with respect to the left and right traveling drive shafts (37L, 37R)
The vehicle is turned by giving a difference, and the left and right sun gears (67) in the left and right planetary gear units (41L, 41R) are integrally formed on the outer peripheral surface of the main drive shaft (40). A traveling device for a working vehicle, comprising a tooth profile (40a), wherein the input gear (63) is fitted on a main drive shaft using the tooth profile (40a).