JP4233156B2 - Gearbox for work equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission for a working machine such as a combine.
[0002]
[Prior art]
Conventionally, a transmission for a working machine such as a combiner is provided with a hydrostatic continuously variable transmission, and only the capacity adjustment of the hydraulic pump of the hydrostatic continuously variable transmission is used to change and adjust the vehicle speed continuously. Had to do.
[0003]
[Problems to be solved by the invention]
For this reason, in the conventional transmission of the working machine, a separate gear-type transmission is provided as a sub-transmission so that a sub-transmission of a plurality of high and low stages can be performed. By the way, since the gear change of the sub-transmission device is performed in a state where the operation resistance with the meshing load between the gears is high, the gear change is difficult to be smoothly performed.
[0004]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a transmission for a working machine that can smoothly perform shift switching using a hydrostatic continuously variable transmission.
[0005]
[Means for Solving the Problems]
(Configuration) A transmission for a working machine according to a first aspect of the present invention is configured such that the capacity of each of a hydraulic pump and a hydraulic motor of a hydrostatic continuously variable transmission for traveling shift can be adjusted by changing a swash plate angle. A shift lever that can be swung linked to a pump operating shaft for changing the swash plate angle of the hydraulic pump, and a switching operation tool that can be operated with a fingertip provided at a grip portion of the shift lever, When the shift lever is swung without operating the switching operation tool, the swash plate angle of the hydraulic motor is maintained at a constant swash plate angle, and the swash plate angle of the hydraulic pump is swung by the shift lever. to so that is changed to a high speed side in accordance with the amount, switching between motor operating shaft for operating change swash plate angle of the said transmission lever hydraulic motor in a non-linked state, the shift lever by operating the switch operating member Swing operation Then, the swash plate angle of the hydraulic motor is switched from the constant swash plate angle to the high speed side, and the swash plate angle of the hydraulic pump is changed to the high speed side in accordance with the swing operation amount of the shift lever. The motor operating shaft and the switching operation tool are connected via a linkage mechanism that switches the shift lever and the motor operating shaft to a linked state .
[0006]
[0007]
[0008]
[0009]
[0010]
[0011]
[0012]
According to the configuration according to claim 1 of the (working) the present invention, the capacity change of the oil pressure motor is made, should the rate set corresponding to the working speed, etc. in the case of traveling while working to obtain Thus, the vehicle speed can be set.
Further, since the switch operating tool is provided in the grip portion of the speed change lever, it can be switched by a one-handed operation by a hand operating the speed change lever as compared with the case where a separate speed change tool is provided at a position away from the speed change lever. Therefore, another operation can be performed with the other hand not operating the shift lever.
[0013]
(Effect) Therefore, according to the configuration of the first aspect of the present invention, the vehicle speed can be set so that the necessary speed set corresponding to the work speed when traveling while performing work can be obtained. appropriate speed setting is supposed to perform with pre Me set, it becomes used freely good.
In addition, since the operation of the shift lever and the switching operation of the shift operation tool can be performed with one hand operation, it is possible to obtain an excellent operability of the shift operation.
[0014]
(Structure) According to a second aspect of the present invention, there is provided a transmission device for a working machine according to the first aspect, wherein when the switching operation tool is operated to swing the shift lever, the swash plate of the hydraulic motor is provided. The motor operation shaft and the switching operation tool are connected via the linkage mechanism so that the angle is gradually switched from the constant swash plate angle to the high speed side.
[0015]
[0016]
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a combine as an example of a work machine. This combine is equipped with a cutting pre-treatment device 3 that swings up and down around a horizontal axis core at the front end of a body frame 2 supported by a pair of left and right crawler travel devices 1, 1. The threshing device 4, the boarding operation unit 5, the driving unit 6, the Glen tank 7 and the like are mounted and configured.
[0018]
As shown in FIGS. 2 to 5, the power from the engine E of the prime mover 6 is input to the hydrostatic continuously variable transmission 9 via the belt transmission mechanism 8, and this hydrostatic continuously variable transmission. 9 is input to the mission case 10 and transmitted to the crawler traveling devices 1, 1, and a separate output is obtained from the mission case 10 so as to be driven in synchronization with the crawler traveling devices 1, 1. The pre-processing device 3 is driven. Further, transmission to the threshing device 4 is performed in a separate system from transmission to the crawler traveling devices 1, 1 and the pre-cutting processing device 3.
[0019]
The hydrostatic continuously variable transmission 9 is connected to a transmission case 10 with bolts or the like, and a hydraulic pump is driven by the rotational power of the input shaft 9A to which power from the belt-type transmission mechanism 8 is input to the input shaft 9A. Drive P. The hydraulic oil discharged from the hydraulic pump P drives the hydraulic motor M. The hydraulic pump P is a variable displacement swash plate type pump, and a pump operating shaft 11 for changing the swash plate angle protrudes outside the case of the hydrostatic continuously variable transmission 9. On the other hand, the hydraulic motor M is also a variable displacement swash plate type motor, and a motor operation shaft 12 for changing the swash plate angle protrudes outside the case of the hydrostatic continuously variable transmission 9. Further, the output shaft 9B of the hydraulic motor M is interlocked and connected to the mission case 10. And the speed change lever 13 is provided in the boarding operation part 5 so that rocking | fluctuation back and forth is possible. The shift lever 13 is configured to be swingable back and forth about the swing center X, and extends to the opposite side of the swing center X with respect to the grip operating portion 13a. An operating wire 14 linked to the arm 11A of the pump operating shaft 11 is connected to the arm portion 13b.
[0020]
The grip operating portion 13a as a grip portion for manual operation of the shift lever 13 is provided with a swing operation lever 15 as a switching operation tool that can be swung around a horizontal axis so as to be swingable with a fingertip. I support. The swing operation lever 15 is configured in a bell crank shape, and one end of a rod 16 is pivotally supported on an arm portion 15a of the swing operation lever 15, and a switching guide made of sheet metal is connected to the other end of the rod 16. It is pivotally supported at one end of the body 17. That is, the arm portion 15 a of the swing operation lever 15 is pivotally supported on the upper end of the rod 16 that is vertically inserted into the shaft 18 while being positioned in the hollow shaft 18 of the speed change lever 13. A switching guide body 17 is pivotally supported at the lower end. The switching guide body 17 has a long hole 19 formed in the front and rear, and a pin 20 engaged with the long hole 19 is provided on the arm portion 15a. A step portion 21 is provided at the upper edge portion of the long hole 19 at an intermediate position in the longitudinal direction, and the front side of the step portion 21 has a wide front side long hole 19 </ b> R up and down, and a rear side of the step portion 21. The side is a rear long hole 19F that is narrow in the vertical direction, and the pin 20 contacts the stepped portion 21 in the front-rear direction when the switching guide body 17 is in the state where the rod 16 is lowered most. . In addition, one end of the operation wire 22 is connected to the front end of the switching guide body 17 so as to advance and retreat in the front-rear direction, and the other end of the operation wire 22 is connected to the arm 12A of the motor operation shaft 12. Connected. Furthermore, the rod 16 is elastically biased so as to be positioned on the upper side.
[0021]
With the above configuration, as shown in FIGS. 2 and 3, when operating the speed change lever 13 without operating the swing operation lever 15, the vehicle speed of the speed change lever 13 is changed as shown by the solid line in the graph of FIG. 6. Only the change adjustment of the discharge flow rate of the hydraulic pump P of the hydrostatic continuously variable transmission 9 is performed in a state substantially proportional to the operation amount. That is, since the switching guide body 17 is in a posture in which the rear end portion is displaced upward by the rod 16 elastically biased upward, the movement of the pin 20 accompanying the swing of the speed change lever 13 is moved to the step portion 21. The switching guide body 17 is not operated back and forth because the pin 20 can freely move between the front long hole 19R and the rear long hole 19F over the entire range from the zero speed position to the highest speed position without contact. For this reason, the hydraulic motor M is maintained at a constant swash plate angle without being shifted.
On the other hand, as shown in FIGS. 4 and 5, the swing operation lever 15 is operated together with the speed change lever 13 so as to lower the switching guide body 17 against the biasing force by operating the swing operation lever 15. Then, the rod 16 is lowered, and the pin 20 can come into contact with the stepped portion 21. In this state, when the speed change lever 13 is operated from the zero speed to the maximum speed, as shown by the broken line in the graph of FIG. 6, the time from the zero speed until the pin 20 contacts the stepped portion 21 is reached. The vehicle speed is operated to the high speed side by the hydraulic pump P, the hydraulic motor M is maintained at a constant swash plate angle, and the range from the pin 20 contacting the stepped portion 21 to the maximum speed. Then, in conjunction with the operation of the speed change lever 13, not only the hydraulic pump P but also the hydraulic motor M is switched to the high speed side by pulling the operation wire 22, so that only the hydraulic pump P is operated at high speed. The vehicle speed is higher than when operating to the side.
[0022]
[Another embodiment]
As shown in FIG. 7, the arm portion that swings integrally with the speed change lever 13 and the arm 11 </ b> A of the pump operation shaft 11 of the hydrostatic continuously variable transmission 9 are linked by the operation wire 14, and by the clutch 23. A cam body 24 that can be intermittently connected to the shaft 18 of the transmission lever 13 is provided, and a cam follower 25 that includes a roller 25a that is in contact with the cam body 24 and an arm 25b that swingably supports the roller 25a is provided. One end of the arm 25 b and the arm 12 A of the motor operation shaft 12 of the hydrostatic continuously variable transmission 9 are linked by an operation wire 22. The clutch 23 is linked via a switching lever 15 as a switching operation tool provided on the grip portion 13a of the transmission lever 13 and a rod 16 or the like, and is normally biased toward the clutch disengagement side. The on / off operation of the clutch 23 can be performed only when the speed change lever 13 is at the zero speed operation position. The cam body 24 has a length in a radial direction with respect to the outer periphery of the cam body 24 with respect to the swing center X of the shift lever 13 at a plurality of positions corresponding to a predetermined swing angle corresponding to a shift operation of the shift lever 13. A stepped portion 27 is formed so as to change. Thus, when the speed change lever 13 is operated with the clutch 23 engaged, the capacity of the hydraulic motor M is adjusted together with the hydraulic pump P so that the speed increase operation is performed in a plurality of stages corresponding to the operation position of the speed change lever 13 (see FIG. (See graph 8). On the other hand, when the shift lever 13 is operated with the clutch 23 disengaged, only the hydraulic pump P is adjusted in capacity.
[Brief description of the drawings]
FIG. 1 is an overall side view showing a combine. FIG. 2 is an explanatory diagram of a neutral position with a shift lever adjusting the capacity of only a hydraulic pump. FIG. FIG. 4 is an explanatory diagram of the neutral position with the shift lever adjusting the capacity of the hydraulic pump and the hydraulic motor. FIG. 5 is an explanatory diagram of the maximum speed position with the shift lever adjusting the capacity of the hydraulic pump and the hydraulic motor. 6] A graph showing the relationship between the lever operation amount and the vehicle speed. [Fig. 7] An explanatory diagram of the neutral position in a state where the shift lever adjusts the capacity of the hydraulic pump and the hydraulic motor. [Fig. Graph [Explanation of symbols]
9 Hydrostatic continuously variable transmission
11 Pump operation shaft
12 Motor operation shaft 13 Shift lever 13a Grip part 15 Swing operation lever (switching operation tool)
M Hydraulic motor P Hydraulic pump

Claims (2)

Each of the hydraulic pump and hydraulic motor of the hydrostatic continuously variable transmission for traveling speed change is configured so that the capacity can be adjusted by changing the swash plate angle,
A shift lever capable of swinging operation linked to a pump operation shaft for changing the swash plate angle of the hydraulic pump, and a switching operation tool operable at a fingertip provided at a grip portion of the shift lever,
When the shift lever is swung without operating the switching operation tool, the swash plate angle of the hydraulic motor is maintained at a constant swash plate angle, and the swash plate angle of the hydraulic pump is swung by the shift lever. to so that is changed to a high speed side in accordance with the amount, switching between motor operating shaft for operating change swash plate angle of the said transmission lever hydraulic motor in a non-linked state, the shift lever by operating the switch operating member When the swash plate angle of the hydraulic motor is switched from the constant swash plate angle to the high speed side, the swash plate angle of the hydraulic pump is changed to the high speed side according to the swing operation amount of the shift lever. As described above, a transmission for a work machine in which the motor operating shaft and the switching operation tool are connected via a linkage mechanism that switches the shift lever and the motor operating shaft to a linked state . When the switching lever is operated to swing the shift lever, the swash plate angle of the hydraulic motor is gradually switched from the constant swash plate angle to the high speed side through the linkage mechanism. The transmission for a working machine according to claim 1, wherein an operation shaft and the switching operation tool are connected.

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