JPH0268272U - - Google Patents

Description

[Brief explanation of drawings]

The drawings show an embodiment of the steering operation structure for a work vehicle according to the present invention, in which FIG. 1 is a front view of the operation system of the first switching valve and the hydraulic cylinder, and FIG. 2 is a front view of the operation lever from the state shown in FIG. Fig. 3 is a front view of the operating plate and push full wire corresponding to the state in which the lever is operated to the left side clutch disengaged position, and Fig. 3 is a front view of the operating plate corresponding to the state in which the operating lever is operated to the left braking position from the state shown in Fig. 1. 4 is a front view of the operating plate and push full wire corresponding to the state shown in FIG. 1 when the operating lever is moved to the left reverse position, and FIG. 5 is a front view of the push full wire. Figure 6 is a front view corresponding to the state in which the control lever is operated with the switching valve and the control plate difficult to move.
, 2 and 3 switching valves, a hydraulic circuit diagram showing the connection state of the hydraulic cylinder and the variable relief valve, Fig. 7 is a front view of the vicinity of the operating lever, Fig. 8 is a side view of the vicinity of the operating lever, and Fig. 9 is the first A longitudinal side view showing the operation system of the switching valve, and FIG. 10 is a longitudinal front view showing the second switching valve, variable relief valve, and its operating system, and corresponds to the state in which the operating lever in FIG. 7 is operated to the neutral stop position. Figure 11 is a vertical cross-sectional side view showing the operating system of the second switching valve and variable relief valve, and Figure 12 shows the operating system of the second switching valve and variable relief valve. FIG. 13 is a front view corresponding to the state in which the clutch is being operated (rear view relative to FIG. 10), and FIG. 13 shows the second switching valve and A front view of the operation system of the variable relief valve; FIG. 14 is a longitudinal sectional front view of the second switching valve, the variable relief valve, and its operation system corresponding to when the operation lever in FIG. 7 is operated to the right or left braking position; Fig. 15 is a longitudinal sectional front view of the second switching valve, variable relief valve, and its operating system corresponding to when the operating lever in Fig. 7 is operated to the right or left reverse position, and Fig. 16 is a front view of the transmission case of a combine harvester. FIG. 17 is a side view of the front half of the combine harvester. 24...Traveling device, 25R, 25L...Side clutch, 28...Handbrake, 33...Switching valve, 36...Control valve, 39...Operation lever, 4
4...Elastic body, 45...Linkage mechanism, _L1 ...Operation stroke of the linkage mechanism, _L2 ...Displaceable range of the elastic body.

Claims (1)

[Scope of utility model registration request] A pair of hydraulically operated side clutches 25 that turn on and off power to the pair of left and right traveling devices 24, 24.
25L and a hydraulically operated side brake 28 that applies braking to one of the traveling devices 24, 24, the steering operation structure for a working vehicle includes a side clutch 25R, 25L, and a hydraulically operated side brake 28 for applying braking to one of the traveling devices 24, 24. A control valve 36 that interlocks and connects the switching valve 33 and the operation lever 39 via an elastic body 44 and a linkage mechanism 45, and changes the operating pressure of the handbrake 28.
and the operating lever 39 are interlocked and connected via mechanical flexibility A ₁ , A ₂ that absorbs the operating stroke below the setting, and the switching valve 33 is switched by a series of operations of the operating lever 39 . The steering operation structure for a working vehicle is configured such that the control valve 36 is operated from 1 to ₄ , and the movable range _L2 of the elastic body 44 is set smaller than the operation stroke L1 of the linkage mechanism 45.