JPH06199140A - Oil filter installing structure for agricultural work vehicle - Google Patents

Abstract

PURPOSE:To provide an oil filter installing structure with which manufacturing manhours can be reduced and maneuvering part space around an operation part can be secured sufficiently. CONSTITUTION:In an oil filter installing structure for an agricultural work vehicle constituted so as to supply operating oil sucked from inside of a transmission case by a charge pump to a speed change operating hydraulic circuit in a static oil pressure type continuously variable transmission through an oil filter 26, an installing part 28a is formed in a bearing bracket 28 to support and bear a speed change operating trunnion shaft 21 of the static oil pressure type continuously variable transmission, and an oil filter 26 is installed in/ supported with this installing part 28a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is configured to replenish hydraulic oil sucked from a tank by a charge pump to a hydraulic circuit for gear shift operation in a hydrostatic continuously variable transmission through an oil filter. The present invention relates to an oil filter mounting structure for agricultural vehicles.

[0002]

2. Description of the Related Art In the above-mentioned oil filter mounting structure for agricultural work vehicles, in the prior art, for example, Japanese Utility Model Laid-Open No. 54-18383
As disclosed in Japanese Patent Publication No. 8, a hydrostatic continuously variable transmission is arranged between an engine and a rear transmission case, and the oil filter is attached to an upper portion of the hydrostatic continuously variable transmission in a state of protruding upward. There was something.

[0003]

In the above-mentioned conventional structure, since the oil filter is directly attached to the casing of the hydrostatic continuously variable transmission, the filter and the hydraulic circuit of the hydrostatic continuously variable transmission are provided. Although the charging oil passage to be connected can be formed inside the casing, and there is an advantage that external piping is unnecessary, but processing such as forming an opening in the casing of the hydrostatic continuously variable transmission is necessary. At the same time, since the oil filter is arranged in a state where it greatly protrudes upward at the foot of the operator in the central part of the operation step of the aircraft operation part, there are drawbacks such as the foot becoming narrow and the maneuverability is reduced there were. The present invention aims to eliminate the above-mentioned problems.

[0004]

According to the characteristic construction of the present invention, in the oil filter mounting structure of the agricultural work vehicle described at the beginning, it is mounted on a bearing bracket for bearing the trunnion shaft for gear shifting operation of the hydrostatic continuously variable transmission. Forming a part,
The point is that the oil filter is mounted and supported on this mounting portion.

[0005]

[Function] By using the bearing bracket provided on the lateral side of the casing of the hydrostatic continuously variable transmission to support the trunnion shaft for gear shifting operation, the oil filter is attached and supported to provide a hydrostatic The oil filter can be attached directly to the step-variable transmission, and the vertical dimension of the installation location of the hydrostatic stepless transmission is increased without complicating the hydraulic structure by using external piping. Can be suppressed. Moreover, by using the bearing bracket that is continuous with the casing of the hydrostatic continuously variable transmission to support the trunnion shaft, it is not necessary to form a large-diameter opening in the casing itself, and the number of processing steps can be reduced. Can be planned.

[0006]

Therefore, by adopting the rational arrangement structure of the oil filter which is relatively large and takes up space,
There is no need for work such as processing and molding the filter mounting opening in the casing, which is a large member, and the number of manufacturing steps can be reduced, and in general, it is intermediate between the engine deployed at the front and the mission case deployed at the rear. At the position, it is possible to suppress the upward protrusion amount in the arrangement portion of the hydrostatic continuously variable transmission that is arranged at a position located below the operation step,
We have come to be able to provide an advantage in terms of aircraft layout, such as ensuring a sufficient space for the control section around the driving section.

[0007]

Embodiments will be described below with reference to the drawings. Figure 1
An agricultural tractor, which is an example of an agricultural vehicle, is shown in FIG. This agricultural tractor transmits the power of the engine 1 mounted on the front part of the machine body to the front and rear wheels 3 and 4 via the mission case 2, and the rear power take-off shaft 5 provided on the rear part of the machine body and the central power take-off provided on the lower part of the machine body. A transmission system is configured to supply power to the shaft 6. More specifically, as shown in FIG. 2, the power of the engine 1 is the main clutch 7 and the input shaft 8.
Is input to the hydrostatic continuously variable transmission 9 via the auxiliary transmission mechanism 10 and the shift output thereof is supplied to the rear wheel differential mechanism 11 via the auxiliary transmission mechanism 10, while being supplied to the front wheels 3 via the front wheel speed increasing mechanism 12. The airframe traveling drive system is configured as described above. Also, the input shaft 8
The PTO transmission system is configured so that power is supplied to the power take-off shafts 5 and 6 via the hydraulic PTO clutch 14 and the PTO transmission mechanism 15.

As shown in FIG. 3, the hydrostatic continuously variable transmission 9 comprises an axial plunger type variable displacement hydraulic pump 16 and a hydraulic motor 17, and the hydraulic pump 1
By changing the angle of the swash plate 18 of No. 6, the gears can be operated in a continuously variable manner in both forward and reverse directions. The hydrostatic continuously variable transmission 9 includes a case portion 19a integrally formed with a main clutch housing 19 connected to the transmission case 2 and a vertical wall portion 2 connected to the case portion 19a.
It is arranged in the space formed by 0 and. The angle of the swash plate 18 is configured to be changed by rotating the trunnion shaft 21 protruding outward from the side of the case portion 19a. As shown in FIG. 13, the hydrostatic continuously variable transmission 9 includes a hydraulic pump 16 and a hydraulic motor 17.
There is provided a charge circuit 23 for replenishing hydraulic oil to a hydraulic circuit 22 for gear shift operation which connects to and. That is, the gear type charge pump 24 driven by the engine 1 sucks the working oil stored in the mission case 2 as a tank through the oil strainer 25 and supplies it to the hydraulic circuit 22 through the oil filter 26. The charge circuit 23 is configured to do so.

The charge circuit 23 is configured by an internal oil passage formed in the mission case 2 etc. without using a dedicated pipe so that the oil passage is automatically formed by assembling the casing. , The workability of assembly is improved. More specifically, as shown in FIG. 3, the bearing support member 2 is formed in a vertical wall shape on the rear side of the vertical wall portion 20.
7, a trochoid gear 24a is installed in the input shaft support portion of the bearing support member 27 so as to rotate integrally with the input shaft 8 to form a gear type charge pump 24. Then, as shown in FIGS. 3, 9 and 10, an oil strainer 25 is attached to the bottom of the mission case 2 through the lateral side wall so that it can be inserted and removed from the outside and can be freely taken out. The passage L1 is formed in the sidewall of the mission case 2 along the front-rear direction. This mission case 2
As shown in FIG. 11, the oil passage end portion is opposed to the inner oil passage L1 so that the internal oil passage L2 formed in the bearing support member 27 along the longitudinal direction is in communication with the inner oil passage L1. . The upper end of the bearing support member 27 internal oil passage L2 is connected to the charge pump 24. The pressure oil from the charge pump 24 passes through the bearing support member 27, the vertical wall portion 20 and the internal oil passage L3 formed in the case portion 19a to the lateral outside of the case portion 19a, as shown in FIGS. Is supplied to the oil filter 26 arranged in the above-mentioned manner, and the working oil after passing through the filter is supplied to the hydraulic circuit 22 via the oil passage L4 in the case as shown in FIGS. 4 to 8 and 12. Configured. The oil filter 26
Is a bearing bracket 28 that supports the trunnion shaft 21.
The bearing bracket 28 is formed with an internal oil passage which is connected and fixed to the mounting portion 28a integrally formed with the casing portion 19a. In this way, the vertical wall portion 20, the bearing support member 27, the bearing bracket 28 and the like are attached and fixed to the transmission case 2, and at the same time, the internal oil passages are brought into communication with each other to form the charge circuit 23.

It should be noted that reference numerals are added to the claims to facilitate the comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

1] Overall side view of an agricultural tractor

[Fig. 2] Transmission system diagram

FIG. 3 is a vertical sectional side view of a hydrostatic continuously variable transmission.

FIG. 4 is a cutaway front view of the trunnion shaft support portion.

FIG. 5 is a sectional view showing an internal oil passage.

FIG. 6 is a sectional view showing an internal oil passage.

FIG. 7 is a sectional view showing an internal oil passage.

FIG. 8 is a sectional view showing an internal oil passage.

FIG. 9 is a sectional view of an oil strainer installation portion.

FIG. 10 is a cross-sectional view of an oil strainer installation portion.

FIG. 11 is a vertical sectional front view of the bearing support member.

FIG. 12 is a vertical sectional front view of a vertical wall portion.

[Fig. 13] Hydraulic circuit diagram

[Explanation of symbols]

 2 tank 9 hydrostatic continuously variable transmission 21 trunnion shaft 22 hydraulic circuit for shifting operation 26 oil filter 28 bearing bracket 28a mounting part

Claims (1)

[Claims] 1. A hydraulic fluid sucked from a tank (2) by a charge pump (24) is supplied to an oil filter (2).
6) An oil filter mounting structure for an agricultural vehicle configured to replenish a hydraulic circuit (22) for gear shift operation in a hydrostatic continuously variable transmission (9) via 6). A mounting portion (28a) is formed on a bearing bracket (28) for bearing the trunnion shaft (21) for gear shift operation of the speed change device (9), and the oil filter (26) is mounted and supported on the mounting portion (28a). The oil filter mounting structure for the existing agricultural vehicle.