JPS624017Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a gear shift operating device for a tractor.

In general, a transmission device for an agricultural tractor has a large number of gears due to its function. Therefore, a plurality of shift levers, such as a main shift lever, a sub-shift lever, and a slow shift lever, are operated by separate operation levers, or the number of gears is increased by a single operation lever. However, it is troublesome to select the vehicle speed by operating a plurality of operating levers during work, and it is easier to perform a speed change operation using a single operating lever.
However, on the other hand, since the number of gears is large, reliable gear shifting operations become difficult unless the sense of select and shift positions is clear. For this reason, generally a guide groove is formed in the direction of movement of the operating lever and a guide plate is provided with a symbol indicating the gear shift position, but this is cumbersome as it requires visual confirmation of the operating position each time the operating lever is operated. .

This idea was developed in consideration of these points, and allows the driver to reliably perform select and shift operations without visually confirming the position of the operating lever when performing multi-speed shifting using a single operating lever. Moreover, it is an object of the present invention to provide a tractor gear shift operation device that can be operated quickly.

This idea includes a shift rod that defines the sliding motion in the axial direction as the shift position selection motion and the motion around the axis as the shifting motion.
A widening part is fixed to the shift rod, and an actuating body having a facing surface facing the end face of the widening part is provided so as to be slidable about the axis of the shift rod by regulating the stroke and biasing it in one direction. Got tired,
By defining the shift position as the position where the resistance force that the expanding part of the shift rod receives from the operating body changes stepwise or becomes maximum when the shift rod is operated in the select direction, the shift position of the shift rod can be adjusted in the select direction. The position can be perceived very clearly by feel, and when the gear is pulled out, the resistance force will automatically return the shift rod to the neutral position, and the structure can be made simple. It is composed of

A first embodiment of this invention will be explained based on FIGS. 1 to 9. A case 3 is fixed to a transmission case 2 of a tractor body 1 through bolts 4 on its upper opening surface. Inside the transmission case 2, a gear shaft 6 on which a plurality of transmission gears 5 are spline-fitted so as to be able to slide freely in the axial direction, and a gear shaft 8 on which a plurality of transmission gears 7 are fixedly fitted are arranged such that the shaft center in the longitudinal direction is It is also stored. A shift rod 9 having a left-right axis is held within the case 3 so as to be slidable in the axial direction and rotatable around the axis, and one end of the shift rod 9 protrudes from the case 3 and extends laterally. . This extended portion is held by a bearing 10 fixed to the transmission case 2 so as to be slidable in the axial direction and rotatable around the axis, and an operating lever 11 is connected to the tip of the shift rod 9. There is. An arm 12 is fitted onto the outer periphery of the bearing 10 so as to be rotatable around the axis of the shift rod 9, and is connected to the tip of an arm 13 extending downward from the arm 12 so as to be rotatable in the vertical direction. A link 14 is rotatably connected to the lower end of the operating lever 11. A shift lever 16 that selectively engages one of the plurality of shifter forks 15 that engages with the shift gear 5 is fitted into the shift rod 9 within the case 3, and the shift lever 16 is fitted in the widening portion. The boss part 1 is
A pin 18 is inserted through 7 to fix the position.
Furthermore, a pair of actuating bodies 22 are provided within the case 3 and are each comprised of a stopper piece 19, a connecting piece 20, and a facing surface 21. The stopper piece 19 and the opposing surface 21 of the actuating body 22 have an insertion hole 23 formed on the same axis through which the shift rod 9 is inserted so as to be slidable in the axial direction and rotatable around the axis. has been done. In one actuating body 22, the stopper piece 19 is located between one inner surface 24 of the case 3, which is a stopper, and one end face of the boss part 17, and the connecting piece 20 is located between the boss part 17 The opposing surface 21 is located between the other end surface of the boss portion 17 and the stopper piece 19 of the other actuating body 22 . The operating body 22
Bent portions 25 bent toward the other actuating body 22 are formed at both ends of the stopper piece 19, and a spring 26 is inserted between the opposing bent portions 25.

In such a configuration, when the gear shift lever 16 is in the neutral position, the actuating body 22
are pressed by the pressing force of the spring 26, so that each stopper piece 19 is joined to the inner surface 24 of the case 3, and the opposing surface 21 is joined to the end surface of the boss portion 17. If the spring 26 is inserted in a compressed state, the shift rod 9 will not move in the axial direction even if a small amount of external force is applied, and the gear shift lever 16 will be securely held in the neutral position. ing. When the operating lever 11 is rotated in the left-right direction, the shift rod 9 and the speed change lever 16 slide integrally in the left-right direction along the axis of the shift rod 9, and the speed change lever 16 engages with any one of the shifter forks 15. . Further, as the shift rod 9 slides, the boss portion 17 presses the facing surface 21 of one of the actuating bodies 22, causing the actuating body 22 to slide integrally in the sliding direction of the shift rod 9. As a result, the actuating body 2
The stopper pieces 19 of 2 are close together and the spring 2
6 is gradually compressed, and the drag force received from the spring 26 gradually increases as shown in FIG. As shown in FIG. 7b, this resistance becomes maximum at the position where the opposing surface 21 comes into contact with the stopper piece 19 of the other actuating body 22 and the sliding movement of the shift rod 9 is stopped. Then, by setting the neutral position and the position where the resistance of the spring 26 is maximum as the shift position, the driver can move the operating lever 1
Spring 26 without visually checking the position of 1.
The selection operation to an arbitrary shift position can be easily performed by the feeling of resistance of the operating lever 11 due to the drag force. Therefore, by rotating the operating lever 11 in the front-rear direction at each shift position,
Shifter fork 15 engaged by the gear shift lever 16
, the transmission gear 5 is engaged with the transmission gear 7, and as shown in FIG. 9, two gears are set in the neutral position and two gears at each shift position where the gear lever 16 is slid the most in the left and right direction, for a total of two gears. Six speeds can be changed using a single operating lever 11. Furthermore, when the gear is removed, the actuating body 22 is pressed by the drag force of the spring 26, the opposing surface 22 presses the boss portion 17, and the actuating body 22 and the shift rod 9 slide along the axis of the shift rod 9. The gear shift lever 16 is automatically returned to the neutral position. In addition, the drag force of the spring 26 acts only in the select direction of the gear shift lever 16, and the drag force of the spring does not act in the shift direction unlike the center spring method that directly presses the gear shift lever 16. Gear slippage due to drag can be reliably prevented.

Furthermore, by replacing the spring 26 with one having a different spring constant, the resistance feeling of the operating lever 11 can be arbitrarily set, and by changing the mounting method of the actuating body 22 or changing the size or shape. The operating feel can be easily changed.

Next, a second embodiment of this invention will be explained based on FIGS. 10 to 12. Note that the same parts as those explained in FIGS. 1 to 9 are designated by the same reference numerals, and explanations thereof will be omitted. In this embodiment, only one actuating body 22 is provided, and a clamping plate 27 that clamps a spring 26 is fixed to one inner surface 24 of the case 3, facing the bent portion 25 of the actuating body 22. . Therefore, when the shift rod 9 is slid to the right from the neutral position shown in FIG.
The spring 26 is compressed and the drag force of the spring 26 increases as shown in FIG. Shift rod 9 from the neutral position shown in Figure 10.
When sliding to the left, the position of the actuating body 22 remains unchanged, and the shift rod 9 and shift lever 1
6 only slides to the left and the spring 26 is not compressed. Therefore, as shown in FIG. 11, the drag force of the spring 26 does not increase at all. Therefore, as shown in FIGS. 11 and 12, there are two neutral positions of the shift lever 16, but in one position the boss portion 17 is joined to the stopper piece 19 and the shift lever 16 is no longer in the neutral position. cannot be slid, and on the other hand, I begin to feel some resistance when operating the select button. Therefore, it is possible to reliably identify which shift position the shift lever 16 has been selected by feeling the resistance without visually confirming it. Furthermore, when the gear is pulled out, the shift lever 16 is automatically returned to one of the neutral positions.

Next, a third embodiment of this invention will be explained based on FIGS. 13 to 15. Note that the same parts as those explained in FIGS. 1 to 9 are designated by the same reference numerals, and explanations thereof will be omitted. In this embodiment, a connecting piece 2 connecting a stopper piece 19 and an opposing surface 21 is used.
As shown in FIG.
4, the interval between the opposing surfaces 21 is set to be larger than the width dimension of the boss portion 17. Therefore, the neutral position of the gear shift lever 16 exists at two locations where one side of the boss portion 17 is joined to each opposing surface 21. After the boss portion 17 is joined to the opposing surface 21, when the boss portion 17 and the shift rod 9 are further slid in that direction, the operating body 22 also slides together, compressing the spring 26 and increasing the resistance of the spring 26. The resistance of the spring 26 becomes maximum at the position where the opposing surface 21 joins the stopper piece 19 of the other actuating body 22. Therefore, by setting the shift position at each neutral position and the position where the resistance of the spring 26 is maximum on both sides thereof, multi-speed shifting can be easily performed with a single operating lever 11, and the structure is also extremely simple. It is. It should be noted that during the selection operation, the shift lever 16 can be selected to an arbitrary shift position by feeling resistance due to the drag force of the spring 26 without visual confirmation. Also, when the gear is removed, the spring 26
Due to the drag force, the speed change lever 16 is automatically returned to one of the neutral positions.

Since this device is configured as described above, by defining the shift position as the position where the spring resistance changes step by step when the shift rod slides, the driver can visually confirm the shift position by feeling the resistance due to the spring resistance. Since the shift position can be perceived without having to shift, the gear shift operation can be performed quickly and reliably.Furthermore, since multiple shift positions can be provided, multi-stage gear shifting can be performed with a single operating lever. When the gear is pulled out, the gear lever can be automatically returned to the neutral position by the force of the spring, and the structure can be made extremely simple. be.

[Brief explanation of the drawing]

Fig. 1 is a side view of the first embodiment of this invention, with its entire structure scaled down and a portion cut away; A side view with a part of the transmission in cross section, No. 4
The figure is a front view with a part of the transmission in cross section, Figure 5 is an exploded perspective view of the main parts of the transmission, Figure 6 is an enlarged perspective view of the main parts of the transmission, and Figure 7 Figure a is an enlarged plan view of the main parts of the transmission with the gear shift lever in the neutral position, and Figure 7b is an enlarged view of the main parts of the transmission. A partially sectional plan view of the gear shift lever moved in the select direction,
FIG. 8 is a graph showing the movement of the gear shift lever in the select direction and changes in the drag force received from the spring, and FIG. 9 is an explanatory diagram showing the shift pattern.
Fig. 10 shows a second embodiment of this invention, and is an enlarged plan view of the main parts of the transmission with a part cut away, and Fig. 11 shows the movement of the transmission lever in the selection direction and the spring. Fig. 12 is an explanatory diagram showing the shift pattern, and Fig. 13 shows a third embodiment of this invention, showing an enlarged view of the main parts of the transmission and a partial cross-section. FIG. 14 is a graph showing the movement of the gear shift lever in the select direction and changes in the resistance received from the spring, and FIG. 15 is an explanatory diagram showing the shift pattern. 2...Mission case, 9...Shift rod, 11...Operation lever, 16...Shift lever,
17... Boss part (expanded part), 21... Opposing surface, 2
2... Operating body, 24... Inner surface (stopper).

Claims (1)

[Scope of utility model registration request] A shift rod connecting the operating lever and a gear shift lever in the transmission case is supported so as to be slidable in the axial direction and rotatable around the axis, and the movement of the shift rod in the axial direction is defined as a gear shift position selection operation. A movement around the center is defined as a shift movement, a widening part is fixedly provided on the shift rod, and an actuating body having a facing surface opposite to an end face of the widening part is provided so as to be slidable along the axis of the shift rod. , when the opposing surface is pushed by the expanding portion, the actuating body is urged to push back the expanding portion in a neutral direction by the opposing surface, and the stroke of the shift rod is restricted by a stopper; A tractor gear shift operating device characterized by: