JPS6234330Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a gear sliding shifter fork device for a gear sliding type transmission.

In particular, in this invention, the transmission case is made shorter and the width is narrower than before, and inside such a small transmission case, the main transmission of 1 reverse speed and 3 forward speeds, as well as the height and low speed, are housed. Sub-shift and
This relates to a speed change shifter device in which five shaft centers are arranged in a square shape in order to incorporate a gear train that can perform high, medium, and low PTO shifting, creep shifting, etc.

In such a case, a number of gear shifter devices are inserted within a narrow area, making it difficult to position the gear shifter shaft and making assembly complicated.

In order to eliminate these drawbacks, the shaft center is arranged in a square shape, and by utilizing the fact that the shaft center is located near the wall of the transmission case, the shifter fork, which is an integrated fork and shifter shaft, can be inserted and supported on the wall. In addition, the detent device is difficult to remove because it does not have a shifter shaft, so the detent engagement surface is provided integrally with the shifter fork, making it easier to assemble and save space. be.

In addition, the detent device is constructed in the shape of a bolt, with a spring and detent protrusion installed inside the bolt, the head of the bolt is hexagonal, and a threaded portion is also provided, and it is assembled by screwing it into the wall of the mission case. It is something.

The purpose of the present invention is as described above, and the detailed configuration of the present invention will be explained based on the configuration of the embodiment shown in the attached drawings.

FIG. 1 is an overall side view of the agricultural tractor, and FIG. 2 is a drawing showing the internal structure of the transmission case.

An engine 2 is disposed on a bonnet 1, and a front axle bracket 3 protrudes forward from the engine 2. A front differential case 6 is supported by the front axle bracket 3, and front wheels 5, 5 are supported by a front axle that projects laterally from the front differential case 6. The front differential case 6 is driven by a front wheel drive shaft inside the front wheel drive shaft cover 4.

A clutch housing 7 is fixed to the rear surface of the engine 2, and a transmission case 8 is fixed to the rear surface of the clutch housing 7. A rear axle housing protrudes from the side surface of the transmission case 8 or the rear axle case, and the rear wheel 9 is supported by the rear axle housing.

A PTO shaft 10 protrudes from the rear surface of the transmission case 8, and power is transmitted to the working machine via a universal joint. Operation levers protrude from the left and right sides of the transmission case 8. On the left side is the PTO gear shift lever 11, on the right side is the front clutch lever 12 and the auxiliary gear/creep gear lever 13.
Further, a main shift lever 14 is provided protruding from the top surface.

PTO gear shift lever 11 on the side, front clutch lever 12, auxiliary gear shift/creep gear shift lever 1
3, the fender 16 surfaces on both sides of the seat 15 are also used as speed change guide plates. 17 is a hydraulic case, 18
is the steering wheel.

FIG. 2 is an expanded sectional view of the axis showing the gear train of the transmission device. I will explain its structure and at the same time explain its function.

The driving force of the engine 2 is connected and disconnected by a main clutch device within a clutch housing 7, and is transmitted to an input shaft 19 protruding from a transmission case 8.
A main shaft 20 whose front end is supported by a bearing in a hole in the rear end face of the input shaft 14 is supported at the rear on the same axis as the input shaft 19 .

Shafts are arranged at respective positions of the input shaft 19 and main shaft 20 as vertices. A pinion shaft 22 with a pinion 21 carved on the right side facing the direction of travel is located below the front power take-off shaft 2.
3 and the creep shaft 24 are arranged on the same axis.

Further, a counter shaft 25 and a PTO speed change shaft 26 are arranged on the left side surface when facing the direction of travel.

The power input from the input shaft 19 is transferred to the fixed gear 41.
from the fixed gear 27 on the counter shaft 25 to the counter shaft, and further from the fixed gear 27 to the PTO
Power is transmitted to the PTO transmission shaft 26 via a fixed gear 28 on the transmission shaft 26. The aforementioned main shift lever 14 allows for three forward speeds and one reverse speed change.

The main gear lever 14 has two shifter forks 5
0 and 51 are selectively slid on the shifter shafts 50a and 51a. shifter fork 51
slides the sliding gear 31 on the main shaft 20 back and forth to change gears into one reverse and one forward gear, and the shifter fork 50 also moves two sliding gears 33 and 34 on the main shaft 20 back and forth to shift into two forward gears. Performs three forward gear shifts.

In the reverse gear, the rotation of the counter shaft 25 is the fixed gear 3.
5, the sliding gear 31 is always meshed with the other 29 of the two loosely fitted reverse gears 29, 30 on the pinion shaft 22, and the sliding gear 31 is in mesh with the other 29 of the two loosely fitted reverse gears 29, 30.
By engaging with the gear, it becomes a reverse gear.

In the first forward stage, the same sliding gear 31 is the counter shaft 2.
This is achieved by meshing with the fixed gear 32 on the top of the gear.

The second forward stage is one 33 of two sliding gears 33 and 34.
is obtained by meshing with a part of the fixed gear 35.

Three forward speeds are obtained by the other two sliding gears 34 meshing with the fixed gear 42 on the countershaft.

The rotation after the main shift is transmitted from the carved gear 43 of the main shaft 20 to the larger diameter one of the two loosely fitted gears 36, 47 on the pinion shaft 22.

This loosely fitted gear 36 is divided into a normal sub-shift and a creep shift.

When the wide sliding gear 37 on the creep shaft 24 is slid to the right, it meshes with the fixed loose-fit gear 36 and another loose-fit gear 38 at the same time, resulting in a sub-shift.

In this state, the auxiliary transmission sliding gear 39 is connected to the loosely fitted gear 3.
By meshing with the internal gear No. 8, the sub-shift becomes a low speed. The sliding gear 39 is the fixed gear 4 on the main shaft 20.
By meshing with 0, a high speed sub-shift can be obtained.

This sub-shift operation is achieved by sliding the sliding gear 39 back and forth by operating the sub-shift/creep shift lever 13 shown in FIG.

Further, by operating the sub-shift/creep shift lever 13, the wide sliding gear 37 on the creep shaft 24 is also slid back and forth, thereby switching between the creep state and the sub-shift state.

When the wide sliding gear 37 is slid forward, it disengages from the loose-fit gear 36, remains engaged with the loose-fit gear 38, and the front end engaging portion 44 of the wide sliding gear 37 engages with the creep shaft. It engages with the integrated engagement portion 45 and transmits the rotation of the creep shaft 24 to the loosely fitted gear 38.

Let me explain the power transmission system in a creep shift state.

Engraved gear 43 on main shaft 20 and double loose fit gear 3
6 and 47 are engaged, and this rotation is transmitted from the other 47 to the fixed gear 46 on the creep shaft 24, causing the creep shaft 24 to rotate.
The rotation of the creep shaft 24 is transmitted from the engaging portion 45 to the wide sliding gear 37, and from 37 to the loose fit gear 38. As described later, the auxiliary transmission shifter fork 52 and the creep transmission shifter fork 5
3 are operated in association with one sub-shift/creep shift lever 13, so double meshing is prevented.

The front power take-off shaft 23 is driven only when the pinion shaft 22 is rotating to drive the rear wheels, and the rotation of the pinion shaft 22 is driven by the fixed gear 54.
Loosely fitted gear 49 on the front power take-off shaft 23
can be conveyed to. By engaging the engaging portion 48a of the clutch slider 48 with the engaging portion 49a of the loose-fit gear 49, the front power output shaft 23 is connected to the front wheel 5, via the front wheel drive shaft in the front wheel drive shaft case 4.
5 is driven.

PTO shifting is achieved by the sliding of the sliding gear 55 for PTO shifting, low speed PTO shifting is achieved by the engaging portion 55a engaging with the engaging portion 28a of the loosely fitted gear 28, and middle speed PTO shifting is achieved by sliding. A high speed PTO shift is obtained by the gear 55 meshing with the fixed gear 35 on the counter shaft 25, and a high speed PTO shift is obtained by the engaging portion 55b engaging with the loosely fitted gear 56 on the PTO shift shaft 26.

FIG. 3 is a cross-sectional view of the mission case 8.
1 shows a diagram of a variable speed shifter fork device.

The shifter shafts 50a, 5 are controlled by the main gear lever 14.
The shifter forks 50, 51 on the main shaft 20 are moved to selectively slide the double sliding gears 33, 34 and the sliding gear 31 on the main shaft 20, thereby changing the speed between one reverse speed and three forward speeds.

In addition, the shifter fork 58 is rotated by the PTO speed change lever 11, and the sliding gear 55 on the PTO speed change shaft 26 is slid, thereby changing the PTO speed from low to medium to high.

Further, the sliding gear 39 on the pinion shaft 22 is slid back and forth to obtain the height of the sub-shift, and the wide sliding gear 37 on the creep shaft 24 is moved back and forth to switch between creep and sub-shift. Since these are related, the sub-shift/creep shift lever 13 is used to shift the two in a related manner.

When the lever 13 is tilted to the left in the direction of travel, it engages with the sub-shift arm 59, slides the shifter fork 52 from the shaft 66, and slides the sliding gear 39. Furthermore, when the lever 13 is tilted to the right to tilt the creep shift arm 60, the shifter fork 53 is rotated via the link 68 since it is loosely fitted onto the shaft 66.

Figure 4 shows the front clutch levers 12, 12.
FIG. 5 is a front view showing the relationship between the shifter fork 57 and the shifter fork 57. FIG.

Shifter fork 53 and shifter fork 57
are located in overlapping positions in the front-rear direction, with the same axis 2
3 and 24 and a clutch slider 48 are made to slide.

Figure 5 is a front view of shifter fork 53, Figure 6 is a front view of shifter fork 53;
The figure is the same external view, and Figure 7 is the same internal view.
Fig. 8 is a bottom view, Fig. 9 is a sectional view showing the engagement relationship with the detent device, Fig. 10 is an exploded view of the detent device, Fig. 11 is a diagram of the protruding state of the detent projection, and Fig. 12 is a storage It is a drawing showing a state.

Conventionally, the sliding width of the sliding gear was wide, making it difficult to use such a shifter fork and a fork shaft that were integrated, but in this proposal, the sliding width was reduced and the shaft By placing the core close to the wall of the transmission case, it is constructed as a simple shifter fork.

The shifter fork 53 is a U-shaped fork portion 5
3b and lever portions 53c, 53c that engage with the engagement groove,
In addition, the shifter shaft portion 53a and the detent engagement surface 5
3d is integrally constructed.

The detent engagement surface 53d has engagement holes 53e and 53f opened outward, and the detent protrusion 63 of the detent device is located between the creep device and the sub-shift position.
is inserted.

An oil seal fitting groove 53g and a retaining ring 70 fitting groove 53i are provided in the middle of the shifter shaft 53a, and an insertion hole 53h for the arm 61 is provided in the external protrusion.

The structure of the detent device is shown in Figures 10 and 11.
As shown in FIG.

The case 62 of the detent device is made of a bolt, and includes a hexagonal head 62c, a threaded portion 62b, and a guide hole 62a into which the detent protrusion is inserted. A spring 64 is inserted into the insertion hole 62a of this detent protrusion.
is inserted first, then the detent protrusion 63 is inserted, and then screwed onto the wall surface 8a of the mission case 8. An oil groove 63 is provided inside the detent protrusion 63 to prevent rust and fixation due to poor lubrication.
It passes through a. Assembling the shifter fork 53 and detent device is done using the shifter fork 53.
The retaining ring 70 is engaged and fitted by protruding from the inside of the transmission case to the outside, and the arm 61 is inserted, and then the half-assembled detent device is moved outward toward the detent engagement surface of the shifter fork 53. It is then screwed on.

By changing the thickness of the washer shim 65 interposed between the detent case 62 and the outer wall of the transmission case 8, the amount of protrusion of the detent projection can be changed.

As described above, the present invention provides a detent engagement surface on the wall surface of the shifter fork on which the sliding gear slides near the wall surface of the transmission case, and the detent engagement surface is designed to engage with the engagement hole drilled in the detent engagement surface. , a detent protrusion biased by a spring protrudes from the insertion guide hole in the mission case wall, and a lubricating oil groove is provided in the detent protrusion, so that the spring inserted into the insertion guide hole in the mission case wall part 64. The oil groove 63a prevents the sliding part of the detent protrusion 63 from rusting due to lack of lubricating oil, and even if the vehicle is left unused for a certain period of time, it will not rust when changing gears next time. There is no problem with the shift lever's movement.

Furthermore, even if the detent device is located close to a wall where lubricant oil does not splash, lubricant oil flows from the sliding gear through the shifter fork and enters the oil groove.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of the agricultural tractor, FIG. 2 is a side sectional view showing the internal structure of the transmission case, and FIG. 3 is a front sectional view of the transmission case 8.
FIG. 4 is a front sectional view of the front clutch shifter fork, FIG. 5 is a front view of the shifter fork 53, FIG. 6 is an outside view, FIG. 7 is an inside view, and FIG. 8 is a bottom view. FIG. 9 is a sectional view showing the engagement relationship with the detent device, FIG. 10 is an exploded view of the detent device, FIG. 11 is a drawing of the detent projection in the protruding state, and FIG. 12 is a drawing of the same in the retracted state. 8...Mission case, 8a...Mission case wall, 53...Shifter fork, 53a...
...Shifter shaft, 53b...Fork part, 53c...
...Lever, 53d...Detent engagement surface, 53e, 5
3f...Engagement hole, 62...Detent case, 62
a... Fitting guide hole, 63... Detent protrusion, 6
3a...Oil groove, 64...Spring.

Claims (1)

[Scope of utility model registration request] A detent engagement surface is provided on the wall side of the shifter fork on which the sliding gear slides near the wall of the mission case, and the mission case wall is fitted in order to engage with the engagement hole drilled in this detent engagement surface. A speed change shifter device comprising: a detent protrusion urged by a spring protruding from a guide hole; and an oil groove for lubricating oil extending through the detent protrusion.