JPH0558176A - Gear shift transmission device for tractor and the like - Google Patents

Abstract

PURPOSE:To reduce the size of a gear shift transmission device in a transmission case for a tractor etc. CONSTITUTION:A gear shift transmission device for a tractor and the like is formed in such a way that shift gears 10-13 engaged with counter gears 1-4 comprising a pair of axially disposed synchrogears and positioned facing each other and capable of effecting a shift through switching of shifters 8 and 9 are respectively arranged on gear shift shafts 6 and 7 on both sides of a counter shaft 5 having the counter gears 1-4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a tractor, a carrier,
The present invention also relates to a speed change transmission device such as a tractor that can be used as a traveling transmission device for agricultural work machines.

[0002]

2. Description of the Related Art In a mission such as a tractor using a synchro gear, the gear diameter becomes large and the axial width tends to become large, so that the mission case becomes large in size. .. This invention is
An attempt is made to construct a mission as small as possible by the arrangement of transmission gears using a synchro gear.

[0003]

SUMMARY OF THE INVENTION The present invention comprises counter gears having counter gears 1 to 4, and a pair of synchro gears axially arranged on transmission shafts 6 and 7 on both sides of counter shaft 5 and facing each other. Gears 1 to 4 mesh with shifters 8 and 9
It is configured as a speed change transmission device such as a tractor, which is provided with speed change gears 10 to 13 capable of changing speed by switching.

[0004]

[Operation and Effect of the Invention] The transmission of the shift is performed by the shifters 8 and 9
This operation is performed by selectively driving the transmission gears 10, 11, 12 or 13 on the meshing side of the synchro gear. The mechanism of the synchro gear has a relatively large diameter,
Front and rear transmission gears 10 arranged in the axial direction of each transmission shaft 6, 7.
And 11 and between 12 and 13, and further, the counter gears 1 to 4 and the like on the counter shaft 5 facing each other are interposed and meshed with each other.
The large diameter portion of each synchro gear is located between the counter shaft 5 and the synchro gear portions on the opposite shafts 6 and 7 do not interfere with each other, and the transmission gears 10 to 13 have the smallest diameter possible. be able to. Also, the width in the axial direction can be narrowed, and the mission can be miniaturized.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A tractor vehicle body is mainly composed of a clutch housing 15 for connecting an engine 14 to the front part, a transmission case 17 for supporting a pair of left and right rear wheels 16 having a rear axle housing at the rear part, and the like. A front wheel 20 is mounted on the bracket 18 while supporting the front axle housing and steerable by steering handles 19 on both left and right ends. Reference numeral 21 is a hood, 22 is a control step, 23 is a fender, 24 is a pilot seat, and 25 is an operation lever.

The transmission case 2 includes a main transmission 2
6, auxiliary transmission device 27, differential device 28, power take-off shaft 29,
And a power take-off transmission device 30 and the like. The clutch housing 15 includes a main clutch shaft 31 and a reverser 3
2 and the gear shafts 33 to 35, etc.
And a power transmission mechanism that transmits power to the power take-off transmission 30. A reverser shaft 36 parallel to the gear shafts 33 to 35, etc.
Switching clutches 37, 3 in the form of multi-plate clutches by hydraulic pressure
8 and has a forward gear 39 and a reverse gear 40, which are switched and transmitted by the switching clutch 37, and the switching clutch 37 is turned on, the main clutch shaft 31 → the gear shaft 3
3 → forward gear 39 → reverser shaft 36 is interlocked and forward F is transmitted to main transmission 26. When the switching clutch 38 is turned on, the main clutch shaft 31 → gear shaft 33 → gear shaft 35
→ reverse gear 40 → main transmission 2 by interlocking reverser shaft 36
R is transmitted to 6 in reverse. During this period, the power is continuously transmitted from the gear shaft 33 to the power take-out transmission 30 via the gear shaft 34.

The main transmission 26 supports parallel transmission shafts 6 and 7 with the counter shaft 5 sandwiched therebetween, and an input gear shaft 41 connected to the reverser shaft 36 is provided on the front end of the transmission shaft 6.
The auxiliary transmission shaft 42 is connected to the rear end. Further, the speed change shaft 7 is concentric with the power take-off shaft 29 and is supported in the form of a pipe shaft. Of the counter gears 1 to 4 integrated with the counter shaft 5, the counter gear 4 at the front end portion
Mesh with the input gear shaft 41 and the transmission gear 13 on the transmission shaft 7. The counter gear 1 is the transmission gear 1 on the transmission shaft 6.
0, the counter gear 2 meshes with the transmission gear 11,
The counter gear 3 meshes with the transmission gear 12. Speed change gear 1
Synchronous gears 43 and 44 are provided between 0 and 11 and between 12 and 13, respectively. By operating the synchro gear 43 with the shifter 8 and the synchro gear 44 with the shifter 9 in the axial direction, Synchro brake 45, 46
It is possible to perform the selective interlocking of the transmission gears 10 to 13 by rotating the transmission gears in synchronism with each other in sliding contact with each other to engage the synchro gears 43 or 44.

Even if the synchro brakes 45 and 46 and the shifters 8 and 9 and the like are larger than the diameters of the speed change gears 10, 11 and 12, 13 and the like, they are located between the counter gears 1 and 2 and these speed changes are performed. Gears 10-13 and counter gear 1-
It does not interfere with the engagement with 4th grade. In this way, the first gear is obtained when the synchro gear 43 is meshed with the transmission gear 10, and the second gear is obtained when the synchro gear 43 is meshed with the transmission gear 11.
Similarly, when the synchro gear 44 is engaged with the transmission gear 12, the third speed is obtained, and when the synchro gear 44 is engaged with the transmission gear 13, the fourth speed is obtained.

The sub-transmission device 27 is formed between the sub-transmission shaft 42 and the output shaft 47 which is interlocked with the rear differential device 28. Gears 48, 4 are provided at the rear end of the transmission shaft 6.
9 is formed, and a gear 50 is formed at the rear end of the transmission shaft 7. A front end gear 52 of a counter shaft 51 coaxial with the output shaft 47 is meshed between the gears 48 and 50. is doing. The output of the main transmission 26 can be taken out to the transmission shaft 6 and the counter shaft 51.

Similarly to the main transmission 26, the sub-transmission 27 also shifts the synchro gears 53, 54 and the synchro brake 6.
3, 64 and the like. The counter shaft 51
Gears 57 and 58 are formed at the rear end of the auxiliary transmission shaft 42.
Is provided with a rotatable gear shaft 59 and an integral gear 60. The gear shaft 59 meshes with the gear 57 of the counter shaft 51 and the rear portion meshes with the rotatable gear 61 on the output shaft 47. .. The gear 60 meshes with the gear 62 of the output shaft 47.

The gears 49, 58 on the transmission shaft 6 and the counter shaft 51 in which the respective synchro gears 53, 54 are meshed with each other have the synchro brakes 63, 64 positioned on the outer peripheral portions thereof, and are moved in the axial direction by a snap ring or the like. It is locked. Shifter 6
By operating the synchro gears 53, 54 by operating 5, 6, etc., the auxiliary shift can be performed. When the synchro gear 53 is meshed with the gear 49 by the shifter 65, the gear 49 → the auxiliary transmission shaft 42 → the gear 60 → the gear 62 → the output shaft 47.
To get the first speed auxiliary shift. Synchro gear 54 to gear 5
When it is meshed with the gear No. 8, a secondary shift of the second speed via the gear 58 → the output shaft 47 is obtained. When the synchro gear 53 is meshed with the gear shaft 59, the gear 57 → the gear shaft 59 → the auxiliary transmission shaft 42 → the gear 60.
→ Gear 62 → Through the output shaft 47, the third speed is obtained. When the synchro gear 54 is meshed with the gear 61, the fourth speed is obtained through the gear 57, the gear shaft 59, the gear 61, and the output shaft 47.

[Brief description of drawings]

 The figure shows an embodiment of the invention.

FIG. 1 is a vertical sectional view of a transmission mechanism.

FIG. 2 is a side view of the tractor.

[Explanation of symbols]

 1 Counter Gear 2 Counter Gear 3 Counter Gear 4 Counter Gear 5 Counter Shaft 5 Counter Shaft 6 Speed Shaft 7 Speed Shaft 8 Shifter 9 Shifter 10 Speed Change Gear 11 Speed Change Gear 12 Speed Change Gear 13 Speed Change Gear

Claims (1)

[Claims] 1. A pair of synchro gears axially arranged on transmission shafts 6, 7 on both sides of a counter shaft 5 having counter gears 1 to 4, meshing with counter gears 1 to 4 facing each other. A speed change transmission device such as a tractor, which is provided with speed change gears 10 to 13 that can change speeds by switching shifters 8 and 9, respectively.