JPH0320565Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is applied to a tractor, etc. configured to drive a hydraulic actuator such as a power steering device, a hydraulic transmission device, or a lift arm through a hydraulic pump attached to the engine. Regarding the hydraulic system of the work vehicle,
Specifically, the present invention relates to a structure for connecting a hydraulic filter and a hydraulic valve to a hydraulic pump mounted on an engine.

[Conventional technology]

Conventionally, hydraulic filters and hydraulic valves are installed outside the hydraulic tank for ease of maintenance and inspection, and they are individually installed around the hydraulic pump attached to the engine, and each of them is connected to a pipe. was.

[Problem that the invention attempts to solve]

There are various devices and devices around the engine, and therefore hydraulic filters and hydraulic valves must be installed in a relatively narrow space around the hydraulic pump. It is troublesome to install hydraulic filters and hydraulic valves, and it is difficult to connect the pipes of hydraulic filters and hydraulic valves that are located close to each other due to the cramped conditions. This requires a drain pipe to return to the tank, which has the disadvantage of complicating the piping structure and increasing costs.

The present invention integrates a hydraulic filter and a hydraulic valve to make the hydraulic filter and hydraulic valve more compact, reduces the exclusive space occupied by the hydraulic filter and the hydraulic valve, and facilitates the installation and removal of the pipe. The aim is to reduce costs by omitting connections.

[Means for solving problems]

The characteristic configuration of the present invention for achieving the above object is that, when a hydraulic filter and a hydraulic valve are connected to a hydraulic pump mounted on the engine, the hydraulic filter is integrally assembled to a valve casing, and the hydraulic filter is integrally assembled to the hydraulic pump. The suction port for the hydraulic filter of the hydraulic unit and the spring chamber of the hydraulic valve are formed in a state where they partially overlap, so that the valve drain can escape to the suction port. That's what I did.

[Effect]

By integrally configuring the hydraulic filter and the hydraulic valve to form a unit, the hydraulic filter and the hydraulic valve can be mounted to the hydraulic pump in a compact manner. Moreover, since the suction port for the hydraulic filter and the spring chamber of the hydraulic valve are formed in a partially overlapping state, when the suction port for the hydraulic filter and the spring chamber of the hydraulic valve are communicated, it is necessary to There is no need to form a drain port so that it communicates with the suction port from the spring chamber of the valve to the hydraulic filter, and as a result, the hydraulic filter and the hydraulic valve can be placed closer together, making the entire device more compact. , and a pipe connecting the hydraulic filter and the hydraulic pump and a drain pipe for the valve become unnecessary.

[Effect of idea]

Hydraulic filters and hydraulic valves can be mounted compactly on hydraulic pumps, which increases the surrounding work space and makes installation and removal work easier.In addition, costs are reduced by eliminating the need for connecting pipes and drain pipes. It came to be measured.

〔Example〕

FIG. 2 is an overall side view showing a tractor as a working vehicle, in which a double pump 3 is attached to a gear box 2 of an engine 1, and transmission case oil is supplied from a rear transmission case 4 through a suction pipe 5. is sucked in as hydraulic oil, and the oil discharged from the first pump 3A of the double pump 3 is supplied to the control valve V.
is supplied to the lift cylinder 6 via
The oil discharged from the second pump 3B is configured to be supplied to the controller 7a of the power steering device 7 and the hydraulic transmission 8.

A hydraulic unit A is connected to the double pump 3, in which a hydraulic filter and a hydraulic valve are integrally constructed.

As shown in FIGS. 3 to 5, the hydraulic unit A includes a casing 12 of a hydraulic valve 11 that houses a relief valve 9 for setting the pressure of the power steering and a pressure reducing valve 10 for setting the pressure of the hydraulic clutch for shifting. A mounting seat 12a for connecting a hydraulic filter is integrally molded on the mounting seat 12a, and a screw-in hydraulic filter 13 is removably connected to the mounting seat 12a to constitute a hydraulic unit. The spring chambers 9a and 10 of the relief valve 9 and the pressure reducing valve 10, respectively,
A suction port a to the hydraulic filter 13 is formed in a state where it intersects with a in a plan view and partially overlaps in the vertical direction, and the relief valve 9
The drain from the pressure reducing valve 10 as well as the drain from the pressure reducing valve 10 are discharged to a suction port a to the hydraulic filter 13.

The hydraulic unit A and the double pump 3 are connected through a flange 14 integrally connected to the valve casing 12 so that the outlet port b communicating with the hydraulic filter 13 and the inlet port c of the double pump 3 are connected to each other. connected and also double pump 3
The outlet port d of the second pump 3B and the hydraulic valve A
is connected to an inlet port e through a pipe 15. In the figure, f is a return port from the power steering device 7.

[Another example]

In addition, in the above embodiment, a multiple valve equipped with a relief valve and a pressure reducing valve is used as a hydraulic valve, but it can also be applied to a single valve having only one valve. In a partially overlapping state with the spring chamber, the suction port may be provided in parallel with the spring chamber.

[Brief explanation of the drawing]

The drawings show an embodiment of the hydraulic unit for a work vehicle according to the present invention, and FIG. 1 is a hydraulic circuit diagram, FIG. 2 is a hydraulic piping diagram for a tractor, FIG. 3 is a longitudinal sectional front view showing the hydraulic unit, and FIG. 4 is a hydraulic circuit diagram. is the same plan view, and FIG. 5 is the same side view. 3... Hydraulic pump, 9a, 10a... Spring chamber, 12... Valve casing, 13... Hydraulic filter, A... Hydraulic unit, a... Suction port.

Claims (1)

[Scope of Claim for Utility Model Registration] In an operator's hydraulic system configured to drive a hydraulic actuator via a hydraulic pump mounted on an engine, a hydraulic filter and a hydraulic valve are provided for the hydraulic pump 3 mounted on the engine. The hydraulic filter 13 is integrally assembled to the valve casing 12 to form a hydraulic unit A which is directly connected to the hydraulic pump 3, and the suction for the hydraulic filter 13 of the hydraulic unit A is A hydraulic unit for a working vehicle, in which port a and spring chambers 9a and 10a of hydraulic valve A are formed in a partially overlapping state to allow valve drain to escape to a suction port. The suction port a to the hydraulic filter 13 and the spring chambers 9a and 10b of the hydraulic valve are partially overlapped, such that the spring chambers 9a and 10a of the valve intersect with the suction port a. A hydraulic unit for a working vehicle as set forth in claim 1 of the utility model registration claim.