JPS6247740B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a gear shift operating device for an agricultural tractor.

(B) Prior Art Conventionally, in tractors, a technology is known in which a gear shift lever for changing gears inside a transmission case is extended and protruded from the top surface of a fender.

For example, as in Japanese Utility Model Application Publication No. 57-120134.

(C) Problems to be Solved by the Invention However, the problem with placing the gear shift lever on the fender is that the distance between the gear shift lever and the sliding gear inside the transmission case is long. There were problems with the links connecting them becoming tangled or not working.

In order to solve these problems, the present invention provides a selection shifter or selection arm device that connects the gear shift lever and the transmission case side as an intermediate conversion point between the transmission case and the fender.
The distance between the speed change lever and the sliding gear in the transmission case is made as short as possible in order to prevent link entanglement and complication of assembly.

(d) Means for Solving the Problems The objects of the present invention are as described above, and the configuration for achieving the objects will now be explained.

A shift lever guide 2 is fixedly installed on the upper surface of the fender 3, and the shift lever 1 is fixed within the shift lever guide 2.
In this configuration, the lower end of the gear shift lever 1 is moved on the sliding shaft 6 fixed between the transmission case 17 and the fender 3. Selection shifters 8 and 9 are fixedly attached to the selection arm 5 that slides left and right, and are selectively engaged by the movement of the selection arm 5 left and right by the gear shift lever 1, and are also loosely fitted onto the sliding shaft 6. , a transmission gear sliding arm 2 with the selection shifters 8 and 9 protruding from the side of the transmission case 17;
9 and 30 are connected by joint links 11 and 12.

(E) Embodiment The object and structure of the present invention are as described above. Next, the structure of the embodiment shown in the attached drawings will be explained.

FIG. 1 is a plan view of the speed change operation device of the present invention, and FIG.
The figure is also a side view, and FIG. 3 is a front view.

An engine is disposed within the bonnet of the agricultural tractor, and a clutch housing 31 is fixed to the rear surface of the engine. A center case 16 is fixed to the rear surface of the clutch housing 31,
Mission case 1 on the rear of center case 16
7 is fixed. A hydraulic case 10 is arranged on the upper surface of the transmission case 17. Further, rear axle housings 33L and 33R protrude from both sides of the transmission case 17, and left and right fenders 3L and 3R are mounted and fixed on the rear axle housings 33L and 33R. or,
The front parts of the fenders 3L and 3R are also fixed to the rear ends of the left and right steps.

Also, transmission case 17 and center case 1
6, a gear sliding type transmission is arranged.
A sub-shift lever 14 for operating a sub-shift is protruded from the right side of the transmission case 17. Further, a front wheel drive clutch lever 15 that connects and disconnects power from the front wheel drive is protruded from the lower part of the left center case 16.

Also, 13 on the left side is the PTO gear shift lever, and this
The rotation speed of the PTO shaft can be changed by operating the PTO gear shift lever.

Additionally, a hydraulically operated lever guide 25 is provided between the right side of the seat 24 and the fender 3R.
A position control lever 26 and a depth control lever 27 are arranged on this hydraulic operation lever guide 25. These two hydraulic operating levers 26 and 27 operate a hydraulic control valve within the hydraulic case 10.

The main part of the present invention lies in the interlocking structure from the main shift shift lever guide 2 provided on the left fender 3L and the main shift shift lever 1 into the transmission case 17.

Two sets of transmission gears for main transmission are provided within the transmission case 17, and the transmission lever 1 must select and slide between these two sets of transmission gears.

Transmission gear sliding arms 29 and 30 for sliding the two sets of transmission gears inside the transmission case 17 are protruded from the left outer side of the transmission case 17.
A joint link 12 is connected to this speed change gear sliding arm 29 and pivotally supported on one end of the selection shifter 8. Also, the other transmission gear sliding arm 30
Connect the joint link 11 to the selection shifter 9
is connected to one end of.

The selection shifters 8 and 9 are loosely fitted onto the sliding shaft 6. Further, pins 7L and 7R, which are fitted into the engagement holes of the selection arm 5, protrude from the other ends of the selection shifters 8 and 9.

The selection arm 5 is connected to the lever shaft 4 from the gear shift lever 1.
a and 4b, it can be rotated back and forth and slid left and right, and by sliding the gear shift lever 1 left and right, either the pin 7L or 7R is inserted into the engagement hole 5 of the selection arm, The forward and backward movement of the speed change lever 1 rotates the speed change gear and causes the speed change gear to slide.

A selection arm 5 is fixed to the sliding shaft 6,
Return springs 22 and 23 are arranged on the left and right sides so that the selection arm 5 is always biased toward the neutral side.

Bearing devices 19 and 20 are mounted on the support 1 on the hydraulic case 10 in order to pivotally support the sliding shaft 6 so as to be able to slide left and right.
It is protruded from 8.

As shown in FIG. 3, the sliding shaft 6, selection arm 5, selection shifters 9 and 8, etc., which are the main parts of the present invention, are as follows:
Hydraulic case 1 is located above the left side of transmission case 17.
0 and the fender 3L. This portion is configured as an intermediate conversion point between the speed change lever 1 and the speed change gear.

The effects of the configuration of the present invention will be explained.

Move the shift lever 1 to the shift lever guide plate 2 shown in Fig. 1.
When the selection arm 5 slides left and right in the H-shaped groove inside, the selection arm 5 slides left and right on the sliding shaft 6 against the return springs 22 and 23, and the pin 7L in the engagement hole 5a is pulled out. Either pin can be inserted selectively, such as inserting 7R or removing 7R and inserting 7L.

As shown in FIG. 3, when both pins 7L and 7R are inserted halfway, it is the neutral position,
When the shift lever 1 is rotated back and forth from this state, a double mesh state occurs. This double meshing state is avoided because the shift lever guide 2 is configured in an H-shape so that it cannot rotate back and forth from the state shown in FIG. 3. When the shift lever 1 is in the groove on the right side of the shift lever guide 2, there are two speeds, reverse and forward, and only the pin 7R of the selection shifter 9 is fitted into the engagement hole 5a of the selection arm 5. When the shift lever 1 is rotated back and forth in this state, the shift gear sliding arm 30 is rotated by the joint link 11, and as the shifter moves inside the transmission case 17, one of the shift gears is slid back and forth. This causes the gear to mesh with the reverse gear and the second forward gear.

Also, when the shift lever 1 is in the left groove of the shift lever guide 2, it is in the case of the first forward speed and the third forward speed, and the engagement hole 5a of the selection arm 5 has a
Only the pin 7L of the selection shifter 8 is fitted.
When the shift lever 1 is rotated back and forth in this state, the shift gear sliding arm 2 is moved by the joint link 12.
9 is rotated and the shifter is moved inside the transmission case 17 to cause the other transmission gear to slide back and forth, thereby meshing with the first forward speed gear and the second forward speed gear.

(F) Effects of the Invention Since the present invention is configured as described above, it has the following effects.

First, the sliding shaft 6, selection arm 5, and selection shifters 8 and 9 are provided in a free space outside the mission case without providing a selection shifter or selection arm in a space communicating with the mission case. As a result, the mission case itself can be made smaller compared to the case where these are arranged inside the mission case as in the conventional technology, and the sliding shaft 6 and selection shifters 8 and 9 can be assembled at the same time when assembling inside the mission case. There was no need for it.

In addition, we were able to freely configure the selection shifter and selection arm, which make complex movements, outside the mission case without being restricted by the size of the mission case.
Even if the link or arm of this part were to become tangled, assembly, repair, and inspection became easier.

Second, because the gear shift lever is located on the fender far from the transmission case, a large number of long links and arms must be installed to reach the part of the transmission case where the sliding gear slides. However, by arranging an intermediate conversion point constituted by the sliding shaft 6, selection shifters 8 and 9, and selection arm 5 at an intermediate position between them, the long link or arm connected to the gear shift lever 1 can be operated. There is no need to do so, and the gear can be changed by pushing and pulling the short shift lever 1 and the joint links 11 and 12, so there is no tangle of links or arms, and reliability is improved.

Thirdly, the shifter of the transmission gear in the transmission case 17 is not arranged on the upper surface of the transmission case 17, but protrudes to the side of the transmission case 17 as transmission gear sliding arms 29 and 30, and the shifter of the transmission gear in the transmission case 17 is Since the moving arms 29 and 30 and the selection shifters 8 and 9 are configured to be connected by the joint links 11 and 12, the gear shift operation device can be configured in the space between the fender 3 and the transmission case 17. , the operation can be performed by rotation in the axial and radial direction at a position close to the fender 3 in plane distance, and as in the conventional case, the movement of the selection arm 5 is extended a long distance in the lateral direction to the upper surface of the mission case 17. There is no need for the tip to rotate in the radial direction of the shaft.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the speed change operation device of the present invention, and FIG.
The figure is also a side view, and FIG. 3 is a front view. 1...Shift lever, 2...Shift lever guide,
3... Fender, 5... Selection arm, 6... Sliding shaft, 8, 9... Selection shifter, 11, 12...
Joint link, 17...Mission case,
29, 30...Speed gear sliding arm.

Claims (1)

[Claims] 1. In a configuration in which a shift lever guide 2 is fixedly installed on the top surface of the fender 3, and the shift lever 1 is operated left and right and forward and backward within the shift lever guide 2, thereby slidingly operating a plurality of shift gears in the transmission case 17. ,
The lower end of the gear shift lever 1 is fixed to a selection arm 5 that slides left and right on a sliding shaft 6 fixed between a transmission case 17 and a fender 3.
Selection shifters 8 and 9, which are selectively engaged by the left and right movement of the selection arm 5, are also loosely fitted onto the sliding shaft 6, and the selection shifters 8 and 9 are protruded from the side of the mission case 17. Shift gear sliding arm 2
A gear shift operating device for an agricultural tractor, characterized in that 9 and 30 are connected by joint links 11 and 12.