JPS623307Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a belt-type continuously variable transmission having a continuously variable transmission pulley between a transmission shaft receiving power from an engine and an input shaft of a traveling transmission case, and A gear type forward/reverse switching mechanism is interposed in the transmission system to the axle, and the continuously variable speed pulley is actuated in an increasing/decelerating direction by movement in a primary direction, and the forward/reverse switching mechanism is operated by movement in a secondary direction. A shift guide device is provided which is provided with a control lever that is swingable in a two-dimensional direction for performing a switching operation, and which allows the control lever to move in a secondary direction only at a shift intermediate position set in the middle of a path of movement in the primary direction of the control lever. The present invention relates to a speed change operating device for a working vehicle, which is configured to operate both of the continuously variable speed pulleys to the speed increasing side by primary movement of the operating lever in directions opposite to each other from the speed change neutral position.

With this type of shift operating device for a work vehicle, it is possible to easily and easily perform forward/reverse switching of the machine body and continuously variable speed operation for forward/backward and reverse using a single lever. Since both of the pulleys can be operated to the speed increasing side even if the gear shift is operated in either of the mutually opposing primary directions from the neutral gear shift position, the operating feeling will not be disturbed between the forward gear shift operation area and the reverse gear change operation area. , it is easy to ensure reliable gear shifting operation, for example,
As described in Publication No. 54-157324, the valve is operated by moving the operating lever in the primary direction,
It is conventionally known that this valve operation drives a hydraulic cylinder that operates a movable pulley of a continuously variable speed pulley.

Although conventional devices configured to operate movable pulleys using hydraulic pressure can be conveniently used even when the operating lever and movable pulley are separated, the problem is that the valves are operated using the operating lever. There was a time delay between when the operating lever was operated and when the movable pulley was actually operated, and there was a risk that prompt and appropriate gear shifting operations could not be performed.

The technical problem to be solved by this invention is to simplify the mounting structure of the operating lever without causing any delay in response to operating lever operations while allowing speed shifting operations to be performed quickly and without errors, and to change forward and reverse gears. The purpose is to make it easy to change the characteristics to arbitrary ones.

The technical means taken to solve the above technical problem is to provide a cam mechanism on the input shaft that operates the continuously variable speed pulley to the speed increasing side by rotating in either direction around the axis of the input shaft, The control lever is pivoted to the cam mechanism so that the rotation of the cam mechanism about the input shaft can be selectively switched by moving the control lever in the primary direction from the neutral position of the shift, and the control lever can be freely moved in the secondary direction. It is to support.

The above technical means works as follows.

A cam mechanism is provided on the input shaft, and the operation lever is pivoted to the cam mechanism so that rotation of the cam mechanism around the input shaft axis can be selectively switched by moving the gear shift lever in the primary direction, and can be freely moved in the secondary direction. Because I support you,
Movement of the control lever in the secondary direction switches the forward/reverse switching mechanism, and movement in the primary direction allows the continuously variable speed pulley to be operated to the speed increasing side no matter which direction is operated from the speed change neutral position.

Therefore, the present invention has the following effects.

By moving the operating lever in the secondary direction, the continuously variable speed pulley can be operated from the neutral gear position to the speed increasing side in any direction, so the operating force is directly transmitted to the pulley by the operating lever, and the operating lever can be operated. This can be done quickly without any delay in response to the operation lever, and the mounting structure of the operation lever can be simplified. Moreover, the cam surface of the cam mechanism is, for example, sloped gently so that various working speeds can be easily achieved in the forward speed change operation area, and steeply sloped so that a predetermined running speed can be quickly achieved in the forward speed change operation area. By forming the gear in an inclined manner, it has become possible to easily change the forward and reverse speed change characteristics to desired ones.

Embodiments of the present invention will be described below based on the drawings.

Figure 1 shows a combine harvester, in which a threshing device 2 is mounted on a self-propelled machine body having a pair of left and right crawler-type traveling devices 1, 1, and in front of these, after raising and reaping a planted grain culm, A reaping section 4 is disposed in which the grain is gradually changed to a sideways posture while being conveyed and supplied to the feed chain 3 of the threshing device 2.

As shown in FIG. 2, a belt-type continuously variable transmission 8 is provided between the transmission shaft 5 which is interlocked with a belt on the engine side and the input shaft 7 of the traveling transmission case 6. A gear type forward/reverse switching mechanism 9 is interposed in the transmission mechanism to the axles 23, 23 mounted on the traveling transmission case 6.

The belt-type continuously variable transmission 8 includes the transmission shaft 5
, an input pulley 1 consisting of pulley parts 10A and 10B that are relatively movable near and far in the direction of its rotation axis.
A spring 11 is provided on the input shaft 7 to urge the movable pulley portion 10A of the input pulley 10 to approach the fixed pulley portion 10B, and the input shaft 7 is provided with a pulley portion that is relatively movable near and far in the direction of its rotational axis. A continuously variable speed pulley 12 consisting of 12A and 12B is provided, and the winding diameter of the transmission belt 13 is adjusted by sliding the movable pulley portion 12A of the continuously variable speed pulley 12 in the distance direction relative to the fixed pulley 12B. By changing the speed, the driving speed of the input shaft 7 can be changed steplessly.

3 and 4 show that the movable pulley portion 12A of the continuously variable speed pulley 12 is actuated in the acceleration/deceleration direction by the one-dimensional movement of the operating lever 14 which is swingable in two-dimensional directions, and A shift operating device is shown in which the shift gear 9A of the gear type forward/reverse switching mechanism 9 is operated through a wire 15 to three positions: a forward rotation position, a reverse rotation position, and a shift neutral position. The one-dimensional movement guide groove 16 is formed on the operation guide plate 17 in which the one-dimensional movement guide groove 16 for the lever 14 is formed.
A gear change guide groove 18 is formed in communication with the lever 14 to allow two-dimensional movement of the lever 14 only at a gear neutral position N set in the middle of the lever 1.
4 and the continuously variable transmission pulley 12, a movable pulley of the transmission pulley 12 is provided between the transmission pulley 12 and the continuously variable transmission pulley 12 by one-dimensional movement of the lever 14 from the transmission neutral position N to the mutually opposite forward transmission operation area F and reverse transmission operation area R. A cam mechanism 19 is interposed that operates both portions 12A to the speed increasing side.

The cam mechanism 19 includes a concave cam member 19A fixed to the lever 14 and a movable pulley portion 12.
It consists of a convex cam member 19B fixed to A,
Further, the forward and reverse gear shifting cam surfaces 19a, 19b and 19a' of both of these cam members 19A, 19B,
19b' are formed in the same shape.

Further, the lever 14 and the lever mounting member 20 fixed to the cam member 19A are connected via bolts 21 and nuts 22, 22 in a state where the mounting interval of the lever 14 in one dimension can be adjusted, This bolt 21 is also configured to serve as a fulcrum shaft for moving the lever 14 in the secondary direction.

Incidentally, the forward speed change cam surfaces 19a, 19b and the reverse speed change cam surface 19 of the cam members 19A, 19B
a' and 19b' may be configured in the shapes shown in FIGS. 5 and 6, and in short, they may be set as appropriate depending on the content of the work.

[Brief explanation of the drawing]

The drawings show an embodiment of the speed change operation device for a work vehicle according to the present invention, and FIG. 1 is an overall side view of a combine harvester;
Figure 2 is a transmission system diagram of the main parts, Figure 3 is a partially cutaway view of the speed change operating device, Figure 4 is an enlarged view of the cam mechanism, and Figures 5 and 6 each show other cam mechanisms. It is an enlarged view. 5...Transmission shaft, 7...Input shaft, 9 ...Gear type forward/reverse switching mechanism, 12...Continuously variable speed pulley, 14
...Operation lever, 18...Speed shift operation guide, 19
...Cam mechanism.

Claims (1)

[Scope of utility model registration request] A belt type continuously variable transmission device 8 having a continuously variable transmission pulley 12 is provided between a transmission shaft 5 receiving power from the engine and an input shaft 7 of a traveling transmission case 6.
A gear type forward/reverse switching mechanism 9 is interposed in the transmission system from the input shaft 7 to the traveling axle, and the continuously variable speed pulley 12 is actuated in the acceleration/deceleration direction by movement in the primary direction, and is operated in the secondary direction. An operating lever 14 is provided which can swing in two dimensions to switch the forward/reverse switching mechanism 9 by movement, and the operating lever 14 is only at a neutral shift position set in the middle of the primary direction movement path of the operating lever 14. A speed change guide 18 that allows movement in a secondary direction is provided, and the continuously variable speed pulleys 12 are both operated to the speed increasing side by movement of the control lever 14 in the primary direction from the neutral speed change position in directions opposite to each other. In the speed change operation device for a working vehicle, the input shaft 7 is provided with a cam mechanism 19 that operates the continuously variable speed pulley 12 to the speed increasing side by rotation in any direction around the axis of the input shaft 7, The operating lever 14
The cam mechanism 19 is configured such that the rotation of the cam mechanism 19 about the input shaft 7 can be selectively changed by moving in the primary direction from the neutral shift position, and the cam mechanism 19 can be freely moved in the secondary direction. A gear shift operating device for a work vehicle, characterized by being pivotally supported.