JPH0714050Y2 - Passenger farm work vehicle - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a riding-type agricultural work vehicle provided with a hydraulic continuously variable transmission.

[Conventional technology]

Conventionally, in a passenger farm vehicle, in order to replenish oil to a rear wheel drive hydraulic continuously variable transmission (hereinafter, abbreviated as HST), as disclosed in JP-A-63-235760, There was a charge pump.

[Problems to be solved by the device]

However, in the above-mentioned conventional structure, since the hydraulic pump and the hydraulic motor as well as the charge pump are internally provided in the case of the HST, the internal structure of the HST is complicated and expensive. Generally, the HST is cooled by HST.
Since the cooling fan blows air to the case, the working oil and the like must be cooled after passing through the case. To obtain effective cooling, the cooling capacity of the cooling fan must be large. There was a drawback.

The present invention has been made in view of the above points, and
It is also an object of the present invention to provide a passenger farm work vehicle in which a leak oil reducing structure for T is constructed at a low cost, and the HST can be effectively cooled by rationally arranging the reducing structure.

[Means for Solving the Problems]

In order to achieve the above object, a riding type agricultural work vehicle according to the present invention is provided with a hydraulic continuously variable transmission equipped with a cooling fan in the front part, at the rear part of the machine body, a fuel tank, a lower surface thereof and It is arranged above the hydraulic continuously variable transmission with an air path for guiding the cooling air from the cooling fan backward formed between the hydraulic continuously variable transmission and the natural continuous flow. An oil tank for supplying oil to the hydraulic continuously variable transmission and circulatingly collecting leaked oil from the transmission is provided at the rear of the air passageway.

The operation and effect of this characteristic configuration are as follows.

[Action]

An oil tank that replenishes oil to the hydraulic continuously variable transmission under natural flow and circulates and collects leakage oil from the transmission is provided behind the cooling air passage formed between the transmission and the fuel tank. Since it is provided in the gantry, a charge pump is not provided unlike the conventional case, and the hydraulic continuously variable transmission has a simple structure.

Further, since the oil tank receives the cooling air directly, the replenishing hydraulic oil is cooled separately from the hydraulic continuously variable transmission.

[Effect of device]

With such an effect, an inexpensive oil tank is used and the structure of the hydraulic continuously variable transmission is simplified, so that the cost is reduced as a whole. Further, by cooling the replenishing hydraulic oil separately from the hydraulic continuously variable transmission, effective cooling can be performed and the cooling fan can be made relatively small.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 5 shows a riding lawn mower as an example of a riding farm work vehicle. This lawnmower has a pair of left and right front wheels (1)
Further, the boarding operation unit (3) is mounted on the machine body on which the rear wheels (2) are respectively mounted, and the engine (4) is mounted on the front part of the machine body, and the output from the engine (4) is transmitted to the transmission shaft (5). ), A hydraulic continuously variable transmission (6) for driving rear wheels (hereinafter abbreviated as HST) is provided at the rear of the fuselage, and a fender (seat) for the boarding operation section (3) is provided ( 8), and a mower (9) is provided at the lower part of the machine body so as to be able to move up and down while being arranged between the front and rear wheels (1), (2).

The structure of the rear part of the fuselage provided with the HST (6) will be described in detail.

First, the frame structure will be described with reference to FIGS.
As shown in FIG. 4 and FIG. 4, a pair of left and right pipe frames (10) and (10) forming the main frame of the airframe are arranged in the fender (8) along the front-rear direction. Box-shaped side wall frames (11) and (11) are attached by welding in a state where the rear ends of the frames (10) and (10) hang down to the lower part of the frame.

The HST (6) is formed integrally with the axle case (12) for the rear wheel (2) at the lower part thereof, and the boss portions (13), (13) formed on both sides of the axle case (12). ), The side wall cases (11) and (11) are bolted to the lower ends of the side wall cases (11) and (11) to provide rigidity to the frame structure. And
The boss (16) of the universal joint (15) connected to the transmission shaft (5) from the engine (4) is fitted to the input shaft (14) of the HST (6) projecting forward, and a key not shown is shown. The input shaft (14) and the boss (16) are fixedly connected to each other, and the cooling fan (18) is connected to the flange on the outer periphery of the boss (16) by bolts.

Then, at the rear of the HST (6), the battery (1
9) is placed on a support plate (20) installed between the lower ends of the side wall frames (11), (11), and bent portions (21), () formed on the support plate (20). 22) and (23) hold the position of the battery (19) at the front and both sides. A rear cover (24) for holding the battery (19) vertically and backwardly is installed at the rear of the battery (19). That is, the rear cover (24) is inserted in the hitch mounting bracket (26) at the rear of the support plate (20) so that the L-shaped portion (25) formed on the rear cover holds the upper portion of the battery (19). , On both sides of the side wall frame (1
It is fixed to the rear surface of 1) and 11 by bolts with knobs 27 and 27. A gap is provided between the upper end of the rear cover (24) and the rear end of the fender (8) so that the cooling air from the cooling fan (18) can pass to the outside and the oil tank. (28) can be confirmed from outside the aircraft.

The fuel tank (29) for the engine (4) is supported by the support frames (30) and (30) installed between the pipe frames (10) and (10) and the HST (6).
Is disposed above.

Then, in order for the cooling air from the cooling fan (18) to be guided to the rear of the fuselage, the lower surface of the fuel tank (29) and the HST
An air passage (31) is formed between the front part and the upper part of (6).

In addition, a semi-transparent plastic oil tank (28) that stores hydraulic oil and replenishes the HST (6) by gravity flow is installed in the rear of the fuel tank (29) and HST (6). It is attached to a support stay (32) projecting in a cantilever manner on the right pipe frame (10) at a position facing the road (31). As shown in FIG. 2, the attachment is reinforced by a fin (34) with an auxiliary fixture (33) having a U-shaped cross section and a nut welded to the outer surface on one side thereof. In this state, the pair of left and right mounting portions (35) and (35) projectingly formed on the outer periphery of the rear portion of the oil tank (28) are engaged so as to be sandwiched from the side, and the support stay (32) and the auxiliary mounting tool are attached. (33) and the mounting portions (35), (35), the holes for screw insertion formed in the respective holes are aligned, and then the thumbscrews (36), (36) are attached to the auxiliary fixture (33). It is made by screwing and fastening the nut.

An oil pipe (37) for replenishing oil from the lower end of the oil tank (28) is connected to the HST (6), and the working oil in the HST (6) is returned to the oil tank (28) by its internal pressure. Return pipe (38) goes from HST (6) to oil tank (2
8) Connected to the top.

In the above structure, the cooling fan (18) sends cooling air to the HST (6) by rotating with the input shaft (14) of the HST (6), and also the air passage (31) to the oil tank (28). ) Through cooling air. Further, with the above configuration, the amount of oil in the oil tank (28) can be checked from the gap between the fender (8) and the rear cover (24), and the oil tank (2
8) Oil replenishment, replacement, battery (19) removal, etc.
Easy maintenance work.

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the present invention is not limited to the structure of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of a riding-type agricultural work vehicle according to the present invention. FIG. 1 is a vertical cross-sectional side view showing an essential part, FIG. 2 is a perspective view showing an oil tank mounting structure, and FIG. 3 is an essential part. FIG. 4 is a vertical sectional front view, FIG. 4 is a plan view showing a main part, and FIG. 5 is an overall side view showing a riding type lawnmower. (6) …… hydraulic continuously variable transmission, (18) …… cooling fan, (28) …… oil tank, (29) …… fuel tank,
(31) …… The wind path.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Mikio Yuki 64 Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Iron Works Co., Ltd. Sakai Works (56) References: 59-145123 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A hydraulic continuously variable transmission (6) having a cooling fan (18) at a front portion thereof is arranged at a rear portion of an airframe, and a fuel tank (29) is provided at a lower surface of the fuel tank (29) and the hydraulic continuously variable gear. It is arranged above the hydraulic continuously variable transmission (6) in a state where an air passage (31) for guiding the cooling air from the cooling fan (18) to the rear is formed between the transmission and the transmission (6). In addition, the oil tank (28) for replenishing oil to the hydraulic continuously variable transmission (6) and circulatingly collecting leaked oil from the transmission (6) is provided with the air passage (31 ) A riding-type farm work vehicle that is provided on the rear side of ().