JPH0416206A - Filter apparatus - Google Patents

Abstract

PURPOSE:To make workability at the time of maintenance of a filter apparatus good by making it possible to detach the whole body of a filter apparatus including an filter element from a covering body in a way of unfastening a bolt and pulling out the filter apparatus upward at the time of maintenance. CONSTITUTION:One end part of a guide pipe 24 is attached to almost the center part of a recessed part 22 of a main body cover 21 and a filter element 25 is attached to the other end of the guide pipe 24. A circular check-valve body 31 installed along the outer circumference of the guide pipe 24 while made able to move along in the axial direction of the guide pipe 24 is accelerated toward the main body cover 21 by a spring part 32. Further, a first check-valve 26 which becomes free flow toward the outside of the recessed part 22, second check-valve 27 which becomes free flow toward the recessed part 22 from the other end part of the guide pipe 24, and a safety valve 28 which is formed in the check-valve body 31 of the valve 26 and communication with it when a prescribed pressure is produced toward the recessed part 22 from the outside of the recessed part 22 are installed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a filter device used in a hydraulic circuit or the like.

[Conventional technology]

BACKGROUND ART Conventionally, an in-line filter device has been used in an oil path between a boat of a hydraulic jack and a hydraulic valve device in order to remove foreign matter flowing out from the hydraulic jack and prevent malfunction of the hydraulic valve device.

FIG. 5 is a diagram showing a schematic configuration of a conventional filter device 50. As shown in FIG.

The filter device 50 includes a main body cover 51;
filter element 52 attached to the body cover 51, check valves 53, 54, safety valve 55,
It consists of piping connection ports 56, 57, a case 58 placed over the bottom surface of the main body cover 51, and the like.

The inside of the case 58 is filled with pressure oil H.

A hydraulic pump is connected to the piping connection port 56, for example, via a valve device, and a hydraulic jack boat, for example, is connected to the piping connection port 57, respectively.

In this case, when the pressure oil H discharged from the valve device flows into the pipe connection port 56, it passes through the check valve 54 and flows out from the pipe connection port 57, thereby operating the hydraulic jack.

Conversely, when the return pressure oil H from the hydraulic jack flows into the pipe connection port 57, it flows out from the pipe connection port 56 through the filter element 52 and the check valve 53, and reaches the valve device. During this time, foreign matter in the pressure oil H is removed by the filter element 52. When the filter element 52 becomes clogged, the safety valve 55 is activated, and the pressure oil H flows from the pipe connection port 57 to the pipe connection port 56 through the safety valve 55 without passing through the filter element 52.

[Problem to be solved by the invention]

In the conventional filter device 5o described above, when performing maintenance such as inspection of the filter element 52 or other parts, or when replacing the filter element 52 when the filter element 52 is clogged, the case is 58 had to be removed from the main body cover 51.

Therefore, the workability is poor and the work requires a lot of time and effort, and there is a risk that the pressure oil H in the case 58 may spill and contaminate the surrounding area.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a filter device with excellent workability during maintenance and filter element replacement.

[Means to solve the problem]

In order to solve the above-mentioned problem, the filter device according to the invention of claim 1 includes a main body cover provided with a recess on the inner surface side and a flow path communicating with the recess, and a recess in the main body cover. a guide pipe with one end attached to the center thereof, a filter element attached to the other end of the guide pipe, and an annular check movable in the axial direction along the outer peripheral surface of the guide pipe. A first check valve consisting of a valve body and a spring member that biases the valve body toward the main body cover, and a first check valve that allows free flow from inside the recess toward the outside thereof; A second check valve that has a free flow from the other end side toward the inside of the recess, and a check valve body of the first check valve that has a constant flow from the outside of the recess to the inside of the recess. It consists of a safety valve that opens when pressure is generated.

In the filter device according to the second aspect of the invention, the outer shape of the main body cover is larger than the outer shape of the filter element.

In the filter device according to the invention of claim 3, the second check valve includes a communication hole provided in the guide pipe so that the inside of the guide pipe communicates with the inside of the recess;
and a spherical valve body movably provided within the guide pipe.

In the filter device according to the invention of claim 4, the safety valve comprises:
A communication hole provided in the check valve body of the first check valve, an annular safety valve body provided on the concave side of the communication hole of the check valve body so that the communication hole can be opened and closed, and the safety valve body. and a spring member that urges the check valve body toward the check valve body.

[For production]

When fluid flows in a direction in which the first check valve is free-flowing, fluid does not flow through the second check valve and the filter element.

When fluid flows in the opposite direction, the second check valve opens and the filter element removes foreign matter.

If the pressure increases due to a clogged filter element, etc., the safety valve operates to prevent the pressure from becoming excessive.

The filter device has these filter elements, a first check valve, a second check valve, and a safety valve integrally constructed, and is used by being inserted into a hole provided in a suitable lid or the like. In that case, the entire filter device is pulled out by pulling the main body cover out of the hole.

〔Example〕

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

FIG. 1 is a sectional front view of a filter device 8 according to the present invention.

The filter device 8 includes a main body cover 21 having a recess 22 on the inner surface and a flow path 23 communicating with the recess 22, and a guide pipe 24 having one end 24a attached to the center of the recess 22. , the other end 24 of the guide pipe 24
Filter element 25, first check valve 26, and second check valve 2 connected by screws provided in b.
7, a safety valve 28, etc.

The main body cover 21 consists of a cylindrical fitting part 21a that fits into a hole 3b of a lid 3a, which will be described later, and a prismatic flange part 21b provided on the top thereof.

The filter element 25 has a cylindrical shape whose outer diameter is smaller than the outer diameter of the flange portion 21b of the main body cover 21, that is, the inner diameter of the hole 3b, and the pressure oil H flows inward from its outer surface 25a. This is a known method that sometimes prevents the flow of foreign objects of a certain size.

The first check valve 26 includes an annular check valve body 31 that is movable in the axial direction along the outer peripheral surface of the guide pipe 24 , a compression spring 32 that urges the check valve body 31 toward the main body cover 21 , It consists of a retaining ring 33 that locks one end of the compression bar 232, and a free flow flows from inside the recess 22 to the outside thereof.

The second check valve 27 is movable in the axial direction within the guide pipe 24 through communication holes 41, 41, . A spring pin 43 is attached to the guide pipe 24 to prevent the spherical valve body 42 from falling. It becomes a free flow.

The safety valve 28 has a communication hole 5 provided in the check valve body 31.
1.51..., an annular safety valve body 52 provided above the communication hole 51 so as to be able to open and close the communication hole 51, a compression spring 53 that urges the safety valve body 52 toward the check valve body 31, a compression spring It consists of a retaining ring 54 that locks one end of the recess 53, and communicates when a certain pressure is generated from the outside of the recess 22 toward the inside of the recess 22.

The filter device 8 is inserted from above into a hole 3b provided in the lid 3a of the oil tank 3, and is fixed to the lid 3a by bolts 61, 61, . . . at four corners of the flange portion 21b.

A cylindrical filter case 11 and a bottom cover 12 are attached to the lower surface of the lid 3a by bolts 13, 13, . . . .

In addition, 14 is a packing guide, 34.35.36.37
is Punkin.

A flow path 23 provided in the main body cover 21 communicates with a flow path 3c provided in the lid 3a, and an oil chamber C in the filter case 11 communicates with a flow path 3d provided in the lid 3a. It is possible to connect to the outside by (see 2nd page).

Filter device 8, filter case 11, bottom cover 1
2, and a part of the lid 3a etc., the line filter 7
The oil chamber C is filled with pressure oil H.

Next, the operation of the filter device 8 configured as described above will be explained.

FIG. 2 is a diagram showing an example of a hydraulic circuit using the filter device 8. As shown in FIG.

The flow path 3C of the filter device 8 is connected to the hydraulic pump 5 via the valve device 4, and the flow path 3d is connected to a single-acting hydraulic jack 9, respectively.

Pressure oil H from the hydraulic pump 5 is changed by switching the valve device 4.
When it flows into the flow path 3c, the first chain.

It flows into the hydraulic jack 9 through the flow valve 26 and the flow path 3d, and drives the hydraulic jack 9 upward.

At this time, in the first check valve 26, the compression spring 32 is compressed by the pressure of the pressure oil H, and the check valve body 3
1 is separated from the main body cover 21, thereby allowing the pressure oil H to flow.

When the flow path 3C is connected to the oil tank 3 by switching the valve device 4, the pressure oil H flows into the flow path 3d due to the weight of the ram 9a of the hydraulic jack 9, and the filter element 25,
It returns to the oil tank 3 via the second check valve 27, the flow path 3C1 and the valve device 4.

At this time, in the second check valve 27, the spherical valve body 42 is pushed up by the flow of the pressure oil H from the other end 24b side inside the guide pipe 24, and the pressure oil H flows into the communication hole 4.
1 into the recess 22.

At this time, since the safety valve body 52 is closed by the elastic force of the compression spring 530, the safety valve 28 will not open unless a certain pressure is reached.

When pressure is generated between the oil chamber C and the recess 22 due to clogging of the filter element 25, the safety valve body 52 opens to allow the pressure oil H to flow and prevent the pressure from becoming excessive. .

During maintenance of the filter device 8, the bolts 61.6
1... and pulling the filter device 8 upward as it is, the whole including the filter element 25 can be easily removed from the lid 3a.

Therefore, operations such as inspection of the filter device 8 and replacement of the filter element 25 are extremely easy, and
Since there is no risk of spilling the pressure oil H in the filter case 11,
It does not contaminate the surrounding area (and there is little need to replenish insufficient pressure oil H).

Further, in the filter device 8, the first check valve 2
6. Since the second check valve 27, safety valve 28, and filter element 25 are provided coaxially,
The parts have simple shapes and are easy to process, as well as easy to assemble and disassemble.

By enlarging the filter case 11 and increasing the capacity of the oil chamber C, the line filter can exert a pressure buffering effect, thereby making it possible to absorb the pulsation from the hydraulic pump 5 to some extent.

3 and 4 are diagrams schematically showing examples of how the filter device 8 is used.

In FIG. 3, two filter devices 8.8 are attached to the lid 11b of the case lla, and each filter device 8.8 is attached to the lid 11b of the case lla.
By connecting the flows tII3c and 3d communicating with the flow paths 23 and 8 of No. 8 to the outside, foreign matter can be removed from the flow of the pressure oil H in both directions.

In FIG. 4, the filter device 8.8 is shown mounted horizontally. The effect in this case is similar to that in FIG.

Note that when the filter device 8 is installed laterally as shown in FIG. It is preferable to provide

In the above embodiment, when the outer diameter of the filter element 25 is smaller than the outer diameter of the flange portion 21b, the hole 3
The inner diameter of b is larger than the outer diameter of filter element 25, and the outer peripheral surface of flange portion 21b and hole 3b are
The filter device 8 can be attached to the lid body 3a by providing an annular boss or reducer between the filter device 8 and the lid body 3a.

In addition, first check valve 26, second check valve 27
, the configuration and structure of the safety valve 28, the filter device 8, etc.
The dimensions, number, material, etc. can be changed in various ways other than those described above.

〔Effect of the invention〕

According to the present invention, it is possible to provide a filter device with excellent workability during maintenance and filter element replacement.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional front view of a filter device according to the present invention, Fig. 2 is a diagram showing an example of a hydraulic circuit using the filter device, and Figs. 3 and 4 schematically show examples of use of the filter device. FIG. 5 is a diagram showing a schematic configuration of a conventional filter device. 8... Filter device, 21... Body cover, 22.
- Recess, 24... Guide pipe, 24a... One end 24a, 24b... Other end, 25... Filter element, 26... First check valve, 27... Second Check valve, 28...Safety valve, 31...Check valve body, 32...Compression spring (spring member), 41...Communication hole, 42...Spherical valve body, 51...Communication hole , 52・
...Safety valve body, 53...Compression spring (spring member).

Claims (4)

[Claims] (1) a main body cover provided with a recess on the inner surface side and a flow path communicating with the recess; a guide pipe with one end thereof attached to approximately the center of the recess of the main body cover; A filter element attached to the other end of the guide pipe, an annular check valve body provided so as to be movable in the axial direction along the outer peripheral surface of the guide pipe, and the check valve body urged toward the main body cover. a first check valve made of a spring member that allows a free flow to flow from inside the recess toward the outside thereof; and a second check valve that allows a free flow to flow from the other end of the guide pipe toward the inside of the recess. A check valve, and a safety valve that is provided on the check valve body of the first check valve and communicates with the recess when a certain pressure is generated from the outside of the recess toward the inside of the recess. filter device. (2) The filter device according to claim 1, wherein the outer diameter of the main body cover is larger than the outer diameter of the filter element. (3) The second check valve includes: a communication hole provided in the guide pipe so as to communicate between the inside of the guide pipe and the inside of the recess; and a spherical valve movably provided in the guide pipe. The filter device according to claim 1 or 2, comprising a body. (4) The safety valve includes a communication hole provided in the check valve body of the first check valve, and an annular safety valve provided on the concave side of the communication hole of the check valve body so that the communication hole can be opened and closed. The filter device according to any one of claims 1 to 3, comprising: a body; and a spring member that biases the safety valve element toward the check valve element.