CN112118898A

CN112118898A - Filter device

Info

Publication number: CN112118898A
Application number: CN201980032756.5A
Authority: CN
Inventors: 北岛信行; 若林正法
Original assignee: Yamashin Filter Corp
Current assignee: Yamashin Filter Corp
Priority date: 2018-06-07
Filing date: 2019-06-05
Publication date: 2020-12-22
Anticipated expiration: 2039-06-05
Also published as: CN112118898B; JP7394754B2; JPWO2019235530A1; WO2019235530A1

Abstract

Provided is a filter device which can be applied to a product in use by a user and which is easy to maintain. The lid body provided on the upper side of the tank having the opening portion on the upper surface thereof has a substantially cylindrical flange portion detachably provided on the tank, and a cover assembly detachably provided on the flange portion, the diameter of the hole of the flange portion is larger than the diameter of the filter element, and a hole for providing the detection portion is formed on the outer peripheral surface of the flange portion facing radially inward. The filter element includes a substantially plate-shaped portion provided on an upper side of the flange portion so as to cover the hollow portion of the flange portion, an insertion portion inserted into the hollow portion of the flange portion and the inside of the housing, and a pressing member provided at an end of the insertion portion opposite to the plate-shaped portion and having a substantially annular flat surface portion abutting against a substantially annular sealing member provided on an upper surface of an upper plate of the filter element.

Description

Filter device

Technical Field

The present invention relates to a filter device.

Background

Patent document 1 discloses a filter device in which a differential pressure measurement device is provided in a filter housing.

Documents of the prior art

Patent document

Patent document 1: japanese Kokai publication No. 2018-511465

Disclosure of Invention

Problems to be solved by the invention

However, the invention described in patent document 1 has a problem that the shape of the filter housing is complicated and maintenance such as replacement of the filter element is not easy. In addition, in the invention described in patent document 1, in order to install a differential pressure measurement device in the filter housing, a dedicated filter housing and filter element are required, and there is a problem that the invention cannot be applied to products in use by users.

The present invention has been made in view of such circumstances, and an object thereof is to provide a filter device which can be applied to a product in use by a user and which is easy to maintain.

Means for solving the problems

In order to solve the above problem, a filter device according to the present invention is a filter device provided in a tank having an opening on an upper surface thereof, for example, the filter device including: a substantially bottomed cylindrical case provided inside the tank; a filter element provided inside the housing and having a filter member of a substantially cylindrical shape and an upper plate provided at an upper end of the filter member; a lid body which is provided on the upper side of the tank so as to cover the opening portion, and which has a substantially cylindrical flange portion provided detachably on the tank, and a cover assembly provided detachably on the flange portion; and a detection portion provided in the flange portion, a diameter of the hole of the flange portion being larger than a diameter of the filter element, a hole in which the detection portion is provided being formed on an outer peripheral surface of the flange portion toward a radially inner side, the cover assembly having a substantially plate-shaped plate portion provided in the flange portion so as to cover a hollow portion of the flange portion and an insertion portion provided in the plate-shaped portion and inserted into the housing, a pressing member provided at an end of the insertion portion on a side opposite to the plate portion, the pressing member having a substantially annular flat surface portion abutting against the sealing member, and a substantially annular sealing member provided between the upper plate and the pressing member.

According to the filter device of the present invention, the lid body provided on the upper side of the tank having the opening portion on the upper surface thereof has the substantially cylindrical flange portion detachably provided on the tank, and the cover assembly detachably provided on the flange portion, the diameter of the hole of the flange portion is larger than the diameter of the filter element, and the hole in which the detection portion is provided is formed on the outer peripheral surface of the flange portion facing the radially inner side. In this case, the filter element can be replaced by simply removing the cover assembly, and the filter element can be replaced without requiring additional work such as removing wiring provided in the detection unit.

In addition, according to the filter device of the present invention, the substantially plate-shaped portion provided on the upper side of the flange portion so as to cover the hollow portion of the flange portion is provided with the insertion portion to be inserted into the hollow portion of the flange portion and the inside of the housing, the pressing member having the substantially annular flat surface portion is provided at the end of the insertion portion opposite to the plate-shaped portion, and the substantially annular sealing member is provided between the upper plate of the filter element and the pressing member. In this way, the pressing member presses the filter element, so that the cover of the present invention can be applied to a product in use by a user. Therefore, the conventional filter device can be used as the filter device of the present invention only by replacing the cover without replacing the cover with a dedicated member.

Here, the cover assembly may include an elastic member and a valve, both ends of the elastic member may be provided to the plate-shaped portion and the pressing member, the valve may be provided to the plate-shaped portion, the valve may include a substantially cylindrical valve body provided to the plate-shaped portion, the pressing member may be provided to be movable relative to the valve body, the elastic member may be deformed to press the filter element by the flat surface portion in a state where the cover assembly is attached to the flange portion, and the valve body may be formed to have a height as follows: the front end of the valve does not protrude from the planar portion when the elastic member is undeformed, and the front end of the valve protrudes from the planar portion when the elastic member is deformed. In this way, in the state where the cover assembly is removed, the elastic member that applies a biasing force to the filter element is not deformed, and the valve does not protrude from the flat surface portion, so that the removed cover assembly can be placed on the upper surface of the tank, and the maintainability is further improved.

Here, a first seal member may be provided between the cover assembly and the flange portion, a second seal member may be provided between the valve body and the pressing member, and an amount of deformation of the second seal member may be smaller than an amount of deformation of the first seal member, or a hardness of the second seal member may be softer than a hardness of the first seal member. Thus, the pressing member can be provided so as to be movable in the vertical direction along the outer peripheral surface of the valve body and so as to be movable so as to be inclined with respect to the valve body.

Here, the pressing member may be movable in a vertical direction along an outer peripheral surface of the valve body and may be movable to be inclined with respect to the valve body, a substantially cylindrical positioning portion may be provided on the outer peripheral surface of the pressing member so as to protrude downward, an outer peripheral surface of the upper plate may be provided along an inner peripheral surface of the positioning portion, and a tip of the positioning portion may be notched so that a height of an inner peripheral surface side is low and a height of an outer peripheral surface side is high. The pressing member may be movable in the vertical direction along the outer peripheral surface of the valve body and may be movable so as to be inclined with respect to the valve body, a positioning portion having a substantially cylindrical shape may be provided so as to protrude downward in the pressing member, an inner peripheral surface of the upper plate may be provided along an outer peripheral surface of the positioning portion, and a tip end of the positioning portion may be notched so as to have a low height on the outer peripheral surface side and a high height on the inner peripheral surface side. Thereby, the pressing member moves to automatically position the upper plate and the pressing member. Therefore, even when an operator performs a rough operation such as replacing a plurality of filter elements at a time, the cover assembly can be easily attached.

Here, the pressing member may include a pressing portion body having a substantially cylindrical portion and a substantially annular ring plate portion provided outside the cylindrical portion, and a cylindrical body provided below the pressing portion body, the cylindrical portion being provided along an outer peripheral surface of the valve body, the annular ring plate portion having the flat surface portion. This enables the pressing member to have a simple structure.

Effects of the invention

According to the present invention, it is possible to provide a filter device that can be applied to a product in use by a user and that is easy to maintain.

Drawings

Fig. 1 is a sectional perspective view schematically showing a tank 100 provided with a return filter 1 as an embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view of the return filter 1.

Fig. 3 is a schematic cross-sectional view of the reflux filter 1 in a state where the cover assembly 32 is removed from the flange portion 31.

Fig. 4 is a view showing a state where the cover assembly 32 is removed from the flange portion 31 and the filter element 20 is replaced.

Fig. 5 is a schematic cross-sectional view of the return filter 1, and is an enlarged view showing the vicinity of the lid 30.

Fig. 6 is a schematic cross-sectional view of the return filter 1, and is an enlarged view showing the vicinity of the lid 30.

Fig. 7 is an exploded perspective view of the lid body 30.

Fig. 8 is an exploded perspective view of the lid body 30.

Fig. 9 is a perspective view showing an outline of the return filter 2 according to the embodiment of the present invention.

Fig. 10 is a perspective cross-sectional view schematically showing the return filter 2.

Fig. 11 is a perspective view schematically showing the return filter 2 when the cover assembly 32A is removed from the flange portion 31A.

Fig. 12 is a cross-sectional view schematically showing cover assembly 32A when cover assembly 32A is removed from flange 31A.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, the working oil is described as an example of the liquid to be filtered, but the liquid to be filtered is not limited to the working oil. In the present embodiment, a return filter is described as an example, but the filter device of the present invention is not limited to the return filter.

< first embodiment >

Fig. 1 is a sectional perspective view schematically showing a tank 100 provided with a return filter 1 as an embodiment of the present invention. Hatching for showing the cross section is omitted in fig. 1.

The tank 100 is a tank for storing the working oil. The tank 100 is provided in a working machine (for example, a hydraulic device) not shown, and is provided in a hydraulic circuit of hydraulic oil supplied to the hydraulic device. However, the tank 100 is not limited to being provided in the hydraulic circuit.

The tank 100 is, for example, box-shaped and has a cavity inside. The tank 100 mainly includes a bottom surface 101, an upper surface 102 facing the bottom surface 101, and a side surface 103 substantially orthogonal to the bottom surface 101 and the upper surface 102.

An opening 102a is formed in the upper surface 102. In addition, on upper surface 102, thick portion 102b for attaching return filter 1 is formed around opening 102 a. However, the thick portion 102b is not essential. The return filter 1 is provided inside the tank 100 (here, below the thick portion 102 b). The opening 102a is covered with a lid 30 (described later) of the return filter 1.

The side surface 103 is provided with an inflow portion 104 through which the hydraulic oil flows into the return filter 1. The inflow portion 104 guides the hydraulic oil from the outside of the tank 100 to the inside of the return filter 1 (space S1). The working oil introduced into the return filter 1 is filtered by the return filter 1, flows out to the space S2, and is then stored in the tank 100 (space S3).

An outflow portion 101a for allowing the hydraulic oil in the tank 100 to flow out to a hydraulic pump (not shown) or the like is formed near the bottom surface 101. A suction strainer (not shown) is provided inside the tank 100, and the hydraulic oil that has passed through the suction strainer flows out of the tank 100 from the outflow portion 101 a.

A partition plate 105 is provided inside the tank 100 so that the working oil flowing out of the backflow filter 1 does not directly contact the suction strainer. Note that the partition plate 105 is not essential.

The reflux filter 1 will be explained below. Fig. 2 is a schematic cross-sectional view of the return filter 1. Hatching for showing the cross section is omitted in fig. 2.

The return filter 1 mainly includes a housing 10, a filter element 20, and a cover 30.

The case 10 is made of a material having high corrosion resistance (for example, a metal such as stainless steel). The case 10 is provided inside the tank 100 so as to protrude downward (on the (-z side)) from the upper surface 102 of the tank 100. The housing 10 and the tank 100 may or may not be an integral component.

The case 10 has a substantially cylindrical shape with a bottom, and an upper end surface is open. The interior of the housing 10 is a cavity, and a filter element 20 and the like are provided inside the housing 10.

The housing 10 has a side 11 of a substantially cylindrical shape. An inlet port 12, which is a hole for allowing the hydraulic oil to flow from the inlet portion 104 (see fig. 1) into the interior of the return filter 1, is formed in the side surface 11. By allowing the working oil to flow in from the inlet 12, the working oil is stored in the space (space S1) inside the casing 10 and outside the filter element 20.

In addition, the housing 10 has a bottom surface 13. A substantially cylindrical outflow portion 15 is provided so as to penetrate the bottom surface 13. The outflow portion 15 communicates the space inside the filter element 20 (space S2) with the space outside the housing 10 (space S3, see fig. 1).

The filter element 20 is a member having a substantially cylindrical shape with a bottom, and is provided inside the case 10. The filter element 20 mainly has a filter 21, an outer cylinder 22, an inner cylinder 23, a plate 24, a plate 25, and a sealing member 26. In fig. 2, a portion of the filter element 20 is shown in cross-section.

The filter 21 is a substantially cylindrical member having openings at both ends. The filter member 21 is formed by: filter paper using synthetic resin, paper, or the like is folded into pleats, and both ends of the pleated filter paper are connected to form a cylindrical shape. An outer cylinder 22 is provided outside the filter member 21, and the outer cylinder 22 has a hole through which the working oil passes over substantially the entire area. Further, an inner tube 23 is provided inside the filter member 21, and a hole through which the working oil passes is formed substantially over the entire inner tube 23. However, the outer cylinder 22 is not essential.

A plate 24 is provided at the upper end of the filter member 21. The plate 24 is a member provided along the upper end surface of the filter 21, and covers the upper end surfaces of the filter 21, the outer cylinder 22, and the inner cylinder 23. The plate 24 has a substantially circular ring-shaped planar portion, and a substantially circular ring-shaped seal member 26 is provided on the upper surface (the upper (+ z side) surface) thereof.

In the present embodiment, the sealing member 26 is bonded to the plate 24, but the manner of providing the sealing member 26 to the plate 24 is not limited thereto. For example, a recess may be formed in the plate 24, and the sealing member 26 may be provided on the plate 24 by pressing the sealing member 26 into the recess. The cross-sectional shape of the seal member 26 is substantially plate-like, but the seal member 26 is not limited to this. For example, an O-ring may be provided on the plate 24 as the sealing member.

A plate 25 is provided at the lower end of the filter member 21. The plate 25 is a substantially disk-shaped member provided along the lower end surface of the filter 21, and covers the lower end surfaces of the filter 21, the outer cylinder 22, and the inner cylinder 23. In a state where the filter element 20 is disposed inside the housing 10, the plate 25 is in contact with the bottom surface 13 and the outflow portion 15 via a sealing member, not shown. Accordingly, the working oil filtered by the filter element 20 does not flow out to the space S1.

The lid 30 is provided on the upper side of the can 100 so as to cover the opening 102 a. When the case 10 penetrates the upper surface 102 of the can 100, the lid 30 is provided to the case 10.

The lid body 30 mainly includes a flange portion 31 and a cover assembly 32. The flange 31 is substantially cylindrical and is detachably provided to the tank 100. A substantially cylindrical hole 31b is formed substantially at the center of the flange 31. The diameter d1 of the hole 31b is larger than the diameter d2 of the filter element 20.

A hole 31a is formed in the outer peripheral surface 31e of the flange 31 so as to face radially inward, and a detection portion 63 is provided in the hole 31 a. By providing the detection portion 63 in the hole 31a, the opening of the hole 31a is covered with the detection portion 63. The detector 63 is a differential pressure detector that detects a differential pressure between the space S1 and the space S2. However, the detection unit provided in the hole 31a is not limited to the differential pressure detection device. For example, by providing a temperature sensor in the flange portion 31, the temperature in the space S2 can be measured.

The cover assembly 32 is provided on the upper side (+ z side) of the flange portion 31 so as to cover the hollow portion of the flange portion 31. The cover assembly 32 is provided to be detachable from the flange 31.

Fig. 3 is a schematic cross-sectional view of the reflux filter 1 in a state where the cover assembly 32 is removed from the flange portion 31. By removing the cover assembly 32 from the flange portion 31, the filter element 20 can be replaced.

Fig. 4 is a view showing a state where the cover assembly 32 is removed from the flange portion 31 and the filter element 20 is replaced. The cover assembly 32 removed can be placed on the upper surface 102 of the can 100. Further, since the diameter d1 of the hole 31b is larger than the diameter d2 of the filter element 20 (see fig. 2 and 3), the filter element 20 can be easily taken out. Therefore, maintenance is easy.

Next, the cover assembly 32 will be described in detail. Fig. 5 and 6 are schematic cross-sectional views of the return filter 1, and are enlarged views showing the vicinity of the lid 30. Fig. 5 shows a state in which the valve 36 (described later) is closed, and fig. 6 shows a state in which the valve 36 is opened. Hatching for showing the cross section is omitted in fig. 5 and 6.

The cover assembly 32 mainly has a plate-like portion 33 and an insertion portion 34. The insertion portion 34 mainly includes a main pressing member 35, a valve 36, and an elastic member 37. The plate-like portion 33 is a substantially plate-like member, and is provided above the flange portion 31 so as to cover the hollow portion of the flange portion 31. The insertion portion 34 is provided below (on the (-z) side) the plate portion 33, and is inserted into the hole 31b of the flange portion 31, the opening 102a, and the inside of the housing 10.

Fig. 7 and 8 are exploded perspective views of the lid 30. Fig. 7 shows a state seen from obliquely above, and fig. 8 shows a state seen from obliquely below.

The pressing member 35 is a member provided at an end of the insertion portion 34 opposite to the plate-shaped portion 33, and an elastic member 37 is provided between the plate-shaped portion 33 and the pressing member 35. In other words, both ends of the elastic member 37 are provided to the plate-shaped portion 33 and the pressing member 35. The valve 36 is provided on the lower side (-z side) of the plate-shaped portion 33 and inserted inside the elastic member 37.

The pressing member 35 has a cylindrical portion 35a having a substantially cylindrical shape, a flat surface portion 35b provided on the lower side of the cylindrical portion 35a, and a positioning portion 35c provided on the outer peripheral surface of the flat surface portion 35 b.

The explanation returns to fig. 5 and 6. A valve body 36c (described later) of the valve 36 is provided on the inner peripheral surface of the cylindrical portion 35 a. A seal member 38 (described later) is provided between the cylindrical portion 35a and the valve body 36c, whereby the cylindrical portion 35a is provided so as to be movable relative to the valve body 36 c. An elastic member 37 is provided on the outer peripheral surface of the cylindrical portion 35 a. The elastic member 37 is in contact with the outer peripheral surface of the cylindrical portion 35a and is movable along the outer peripheral surface of the cylindrical portion 35 a.

The flat surface portion 35b has a substantially annular shape, and abuts against the seal member 26 in a state where the cover assembly 32 is attached to the flange portion 31.

The positioning portion 35c is a substantially cylindrical member provided along the outer peripheral surface of the planar portion 35b, and protrudes downward (toward the (-z side). The inner peripheral surface of the positioning portion 35c has a larger diameter than the outer peripheral surface of the plate 24, and the outer peripheral surface of the plate 24 is provided along the inner peripheral surface of the positioning portion 35c in a state where the cover assembly 32 is attached to the flange portion 31. In the present embodiment, the outer peripheral surface of the plate 24 is a cylindrical portion provided outside a substantially annular flat portion, but when no cylindrical portion is provided outside the flat portion, the outer peripheral surface of the flat portion becomes the outer peripheral surface of the plate 24.

The positioning portion 35c has a notch 35d formed by obliquely cutting at the tip (end on the (-z) side). The notch 35d has a tapered shape such that the height of the positioning portion 35c on the inner peripheral surface side is low and the height on the outer peripheral surface side is high. This facilitates positioning of the pressing member 35 and the filter element 20 when the cover assembly 32 is attached to the flange portion 31. The positioning portion 35c is not essential.

The valve 36 is provided on the cover assembly 32 and protrudes toward the lower side (z side) of the cover assembly 32. The valve 36 mainly includes a stem 36a, a valve body 36b movable together with the stem 36a, a substantially cylindrical valve body 36c, an elastic member 36d, and a fixing portion 36 e. One end of the elastic member 36d is provided to the fixed portion 36e, and the other end is provided to the valve body 36 c.

The valve body 36c has a substantially cylindrical shape (see fig. 7 and 8), and is provided in the plate-like portion 33. In a state where the valve 36 is closed (see fig. 5), the valve body 36b abuts against the lower end surface of the valve body 36 c. A plurality of holes 36g penetrating the valve body 36c in the radial direction are formed in the side surface of the valve body 36 c. When the filter 21 is clogged and the pressure in the space S1 becomes high, the valve 36b is pressed against the urging force of the elastic member 36d and separated from the valve body 36c, whereby the valve 36 is opened (see fig. 6). Thus, the working oil flows from the space S1 to the space S2, whereby breakage of the return filter 1 is prevented.

The valve body 36c is formed with a hole 36f that penetrates the valve body 36c in the axial direction. The hole 36f, the hole 33a formed in the plate-shaped portion 33, and the hole 31c formed in the flange portion 31 constitute a flow path 61, and the flow path 61 connects the space inside the hole 31a and the space inside the filter element 20 (space S2). The flow path 61 has a substantially U shape or a substantially "コ" shape when cut along a plane passing through the center axis of the cover assembly 32.

The detection unit 63 can detect the pressure in the space S2 by the flow path 61. Further, the flange 31 has a hole 31d communicating the hole 31a with the space S1, and the detection unit 63 can detect the pressure in the space S1 through the hole 31 d. As a result, the detector 63 can detect the differential pressure between the space S1 and the space S2.

The valve body 36c and the pressing member 35 are sealed by a sealing member 38. Further, the flange portion 31 and the plate portion 33, and the flange portion 31 and the upper surface 102 are sealed by the sealing member 39. The

seal members

38, 39 are, for example, O-rings, and are formed of deformable rubber or the like. The deformation amount of the seal member 38 is smaller than that of a normal seal member (for example, the seal member 39). For example, the deformation amount of the normal seal member is approximately 8% to approximately 30%, whereas the deformation amount of the seal member 38 is approximately 8% or less. Therefore, the pressing member 35 is movable in the vertical direction along the outer peripheral surface of the valve body 36c and is movable so as to be inclined with respect to the valve body 36 c.

The pressing member 35 is not limited to the above, and is provided so as to be movable in the vertical direction along the outer peripheral surface of the valve body 36c and movable so as to be inclined with respect to the valve body 36 c. For example, the deformation amounts of the

seal members

38 and 39 may be substantially the same (substantially 8% to substantially 30%), and the hardness of the seal member 38 may be made softer than the hardness of the seal member 39. By making the sealing member 38 soft, the pressing member 35 is easily moved in the vertical direction along the outer peripheral surface of the valve body 36c and is easily moved so as to be inclined with respect to the valve body 36 c.

As shown in fig. 2, 5, and 6, in a state where the cover assembly 32 is attached to the flange portion 31, the elastic member 37 deforms (compresses), and the flat surface portion 35b presses the filter element 20 downward (in the (-z direction). Thereby, the filter element 20 is disposed inside the housing 10. Further, since the flat surface portion 35b abuts against the seal member 26, the working oil does not leak from between the pressing member 35 and the filter element 20.

In a state where the cover assembly 32 is attached to the flange portion 31, the elastic member 37 is deformed, and thus the tip (lower end) 36h of the valve 36 protrudes downward from the flat surface portion 35b and is inserted into the filter element 20.

On the other hand, as shown in fig. 3, in a state where the cover assembly 32 is not attached to the flange portion 31, the elastic member 37 is not deformed, so that the tip 36h of the valve 36 does not protrude from the flat surface portion 35b, and the valve 36 is accommodated in the pressing member 35. In other words, the valve body 36c is formed to have such a height that the valve 36 protrudes from the flat surface portion 35b when the elastic member 37 is deformed, and the valve 36 does not protrude from the flat surface portion 35b when the elastic member 37 is not deformed. This enables the cover assembly 32 removed to be placed on the upper surface 102 of the tank 100 (see fig. 4), thereby improving maintainability.

Next, the function of the return filter 1 configured as described above will be described. The two-dot chain line arrow in fig. 2 indicates the flow of the working oil.

For example, when the driving of the working machine is started, the hydraulic oil starts to flow in the hydraulic circuit, and the interior of the housing 10 is filled with the hydraulic oil along with the hydraulic oil flowing into the space S1. The hydraulic oil flowing into the space S1 flows from the outside to the inside of the filter member 21, and dust and the like in the hydraulic oil are removed by the filter member 21. The filtered working oil flows out to the space S2. Then, the filtered hydraulic oil flows out from the outflow portion 15 to the space S3.

Since the filter member 21 is clogged when the filtration is repeated, the pressure of the space S1 is increased, and thus the filter element 20 is replaced. When replacing the filter element 20, the work machine is first stopped.

As shown in fig. 3 and 4, when the cover assembly 32 of the lid body 30 is removed from the flange portion 31, the filter element 20 is pulled out through the opening 102a and the hole 31 d. Since the diameter of the opening 102a and the diameter d1 of the hole 31d are larger than the diameter d2 of the filter element 20, the filter element 20 can be replaced by merely removing the cover assembly 32, and maintenance is easy.

Further, since the detection unit 63 is provided in the flange portion 31, the detection unit 63 is not removed from the tank 100 together with the cover assembly 32 while the detection unit 63 is attached to the tank 100 when the filter element 20 is replaced. Therefore, additional work such as removing the wiring provided in the detection unit 63 is not required, and maintenance is easy.

After the used filter element 20 is taken out, the unused filter element 20 is inserted into the housing 10. Since the diameter of the opening 102a and the diameter d1 of the hole 31d are larger than the diameter d2 of the filter element 20, the filter element 20 is also easily inserted.

Thereafter, the cover assembly 32 is attached to the flange portion 31. At this time, as shown in fig. 5, the positioning portion 35c covers the plate 24, but since the cut-out portion 35d is formed at the tip of the positioning portion 35c, the plate 24 and the pressing member 35 are automatically positioned. Therefore, even when an operator performs a rough operation such as replacing a plurality of filter elements 20 at a time, the cover assembly 32 can be easily attached.

It is also considered that maintenance work (for example, repair work) other than replacement of the filter element 20 is performed. In this case, the flange portion 31 and the cover assembly 32 may be removed from the can 100. This facilitates the repair work.

According to the present embodiment, since the diameter d1 of the hole 31b of the flange portion 31 is larger than the diameter d2 of the filter element 20, the filter element 20 can be replaced by merely removing the cover assembly 32, and maintenance is easy. Further, since the detection unit 63 is provided in the flange 31, additional work such as removing wiring provided in the detection unit 63 is not required, and maintenance is easy. Further, since the cover assembly 32 removed can be placed on the upper surface 102 of the tank 100, the maintainability is further improved.

In addition, according to the present embodiment, since the flange portion 31 is provided in the can 100 and the pressing member 35 presses the filter element 20, the lid body 30 of the present invention can be applied to a product in use by a user. Therefore, the conventional filter device can be used as the return filter 1 of the present invention by merely replacing the lid body 30 without using a dedicated filter element.

< second embodiment >

The reflux filter 2 of the second embodiment will be described below. The same parts as those of the reflux filter 1 are denoted by the same reference numerals, and the description thereof is omitted.

Fig. 9 is a perspective view showing an outline of the return filter 2 according to the embodiment of the present invention. Fig. 10 is a perspective cross-sectional view schematically showing the return filter 2. Hatching for showing the cross section is omitted in fig. 10. In fig. 10, a part of the reflux filter 2 is shown in an enlarged manner.

The return filter 2 is provided on an upper surface 102A of the tank 100A for storing the working oil. The tank 100A differs from the tank 100 in the following points: upper surface 102 of tank 100 has thick portion 102b, while upper surface 102 of tank 100A is provided with mounting member 102 c. The inner peripheral surface of the mounting member 102c is an opening 102 a.

The return filter 2 mainly includes a case 10, a filter element 20A, and a cover 30A.

The filter element 20A is a member having a substantially cylindrical shape with a bottom, and is provided inside the case 10. The filter element 20A mainly includes a filter member 21, an outer cylinder 22, an inner cylinder 23, a plate 24A, and a plate 25 (not shown).

A plate 24A is provided at the upper end of the filter member 21. The plate 24A has two cylindrical portions provided on both sides of a substantially annular flat surface portion covering the upper end surfaces of the filter member 21, the outer cylinder 22, and the inner cylinder 23, the outer cylindrical portion covering the outer peripheral surface of the outer cylinder 22, and the inner cylindrical portion covering the inner peripheral surface of the inner cylinder 23.

Lid 30A is provided on the upper side of can 100A so as to cover opening 102 a. When the case 10 penetrates the upper surface 102A of the tank 100, the lid 30A is provided to the case 10.

The lid 30A mainly includes a flange 31A and a cover assembly 32A. The flange portion 31A is provided on the upper side of the upper surface 102A (here, the mounting member 102 c). The flange portion 31A and the mounting member 102c are sealed by the sealing member 39.

The flange 31A is substantially cylindrical and is detachably provided to the tank 100A. A substantially cylindrical hole 31b is formed substantially at the center of the flange 31. The diameter of the hole 31b is larger than that of the filter element 20A.

Flange 31A has a convex portion 31 g. A hole 31A is formed radially inward of a portion of the outer peripheral surface 31e of the flange 31A where the convex portion 31g is provided, and the hole 31A is provided with the detection portion 63. This reduces the diameter of the flange 31A by positioning the detection section 63 radially inward.

The cover assembly 32A is provided on the upper side (+ z side) of the flange portion 31A so as to cover the hollow portion of the flange portion 31A. The cover assembly 32A is provided to be detachable from the flange 31A.

The cover assembly 32A mainly includes a plate-shaped portion 33A and an insertion portion 34A.

The plate-shaped portion 33A is a substantially plate-shaped member, and is provided above the flange portion 31A so as to cover the hollow portion of the flange portion 31A. The plate-shaped portion 33A has a cylindrical portion 33c inserted into the hollow portion of the flange portion 31A. The flange portion 31A and the plate portion 33A are sealed by a sealing member 39. The plate-like portion 33A is provided with a recess 33b into which the protrusion 31g is inserted.

The insertion portion 34A is provided below (on the z-side) the plate portion 33A, and is inserted into the opening 102a and the inside of the housing 10. The insertion portion 34A mainly includes a pressing member 35A, a valve 36A, and an elastic member 37.

The pressing member 35A includes a pressing portion body 35m and a cylindrical body 35n provided below (on the z-side) the pressing portion body 35 m. An elastic member 37 is provided between the plate-like portion 33A and the pressing member 35A (here, the pressing portion main body 35 m). The elastic member 37 applies a downward (-z direction) force to the pressing member 35A.

The pressing portion main body 35m includes a substantially cylindrical tubular portion 35h and a substantially annular ring plate portion 35i provided outside the tubular portion 35 h. A valve body 36p (described later) of the valve 36 is provided on an inner peripheral surface of the cylindrical portion 35h, and the cylindrical portion 35h is provided along an outer peripheral surface of the valve body 36 p. By providing the seal member 38 between the cylindrical portion 35h and the valve body 36p, the cylindrical portion 35h can move in the vertical direction along the outer peripheral surface of the valve body 36p, and the cylindrical portion 35h can move so as to be inclined with respect to the valve body 36 p.

The annular plate portion 35i has a substantially annular flat surface portion 35g, and the flat surface portion 35g is located on the outermost side of the annular plate portion 35 i. A substantially annular seal member 35j is provided on the lower side (the (-z side) of the planar portion 35g, i.e., on the plate 24A side. Therefore, when the cover assembly 32 is attached to the flange portion 31, the seal member 35j is provided between the plate 24A and the pressing member 35A.

The seal member 35j is a substantially annular member. As shown in fig. 12, the cross-sectional shape of the seal member 35j is substantially plate-like. Two protrusions having a substantially circular ring shape are formed on the lower side of the seal member 35 j. However, the aspect of the seal member 35j is not limited thereto. For example, an O-ring may be provided between the plate 24A and the pressing member 35A as the sealing member. Further, the seal member 35j is adhered or bonded to the flat surface portion 35g, but the method of providing the seal member 35j to the flat surface portion 35g is not limited to this.

The explanation returns to fig. 10. A substantially cylindrical positioning portion 35e is provided adjacent to the flat surface portion 35 g. The positioning portion 35e protrudes toward the lower side (-z side). The outer peripheral surface of positioning portion 35e has a smaller diameter than the inner peripheral surface of plate 24A, and the inner peripheral surface of plate 24A is provided along the outer peripheral surface of positioning portion 35e in the state where cover assembly 32A is attached to flange portion 31A. Further, a cylindrical body 35n is provided along the inner peripheral surface of the positioning portion 35 e. The cylindrical body 35n has a plurality of holes formed therein, but the holes are not necessarily required.

In the present embodiment, the inner circumferential surface of the plate 24A is a cylindrical portion provided inside a substantially annular flat portion, but when no cylindrical portion is provided inside the flat portion, the inner circumferential surface of the flat portion becomes the inner circumferential surface of the plate 24A.

The front end (-z side end) of the positioning portion 35e has a notch 35f formed by obliquely cutting. The notch 35f has a tapered shape such that the height of the positioning portion 35e on the outer peripheral surface side is low and the height of the positioning portion 35e on the inner peripheral surface side is high. This facilitates positioning of the pressing member 35A and the filter element 20A when the cover assembly 32A is attached to the flange portion 31A.

The valve 36A is provided below (on the (-z) side) the plate-shaped portion 33A, and is inserted inside the elastic member 37 and the pressing member 35A. The valve 36A mainly includes a stem 36A, an elastic member 36d, a valve body 36o movable together with the stem 36A, a substantially cylindrical valve body 36p, and a fixing portion 36 q. One end of the elastic member 36d is provided to the fixed portion 36q, and the other end is provided to the valve body 36 p.

The valve body 36p has a substantially cylindrical shape and is provided in the plate-like portion 33A. In a state where the valve 36A is closed (see fig. 10), the valve body 36o abuts against the lower end surface of the valve body 36 p. A plurality of holes 36k (see fig. 12) penetrating the valve body 36p in the radial direction are formed in the side surface of the valve body 36 p. When the filter 21 is clogged and the pressure of the space S1 becomes high, the valve body 36o is pressed down against the urging force of the elastic member 36d to be separated from the valve body 36p, whereby the valve 36A is opened. Thus, the working oil flows from the space S1 to the space S2, whereby breakage of the return filter 2 is prevented.

The valve body 36p is formed with a hole 36f that penetrates the valve body 36c in the axial direction. The hole 36f, the hole 33a formed in the plate-shaped portion 33, and the hole 31f formed in the flange portion 31 constitute a flow path 61A, and the flow path 61A communicates the space inside the hole 31A with the space inside the filter element 20A (space S2). The flow path 61A has a substantially L-shape when cut along a plane passing through the central axis of the cover assembly 32A.

The detection unit 63 can detect the pressure in the space S2 through the flow path 61A. Further, the flange 31 has a hole 31d communicating the hole 31a with the space S1, and the detection unit 63 can detect the pressure in the space S1 through the hole 31 d. As a result, the detector 63 can detect the differential pressure between the space S1 and the space S2.

In a state where the cover assembly 32A is attached to the flange portion 31A, the elastic member 37 deforms (compresses), and the flat surface portion 35g presses the filter element 20A downward (in the (-z direction). Thereby, the filter element 20 is disposed inside the housing 10. Further, since the seal member 35j is provided between the flat surface portion 35g and the plate 24A, the working oil does not leak from between the pressing member 35A and the filter element 20A.

In a state where the cover assembly 32A is attached to the flange portion 31A, the elastic member 37 deforms, so that the tip (lower end) 36h of the valve 36A protrudes downward from the lower end of the tubular body 35n, and the tip 36h is inserted into the filter element 20A.

Fig. 11 is a perspective view schematically showing the return filter 2 when the cover assembly 32A is removed from the flange portion 31A. In fig. 11, a part of the reflux filter 2 is shown enlarged. Fig. 12 is a cross-sectional view schematically showing cover assembly 32A when cover assembly 32A is removed from flange 31A. In fig. 12, hatching indicating a cross section is omitted.

In a state where cover assembly 32A is not attached to flange 31A, elastic member 37 returns to an undeformed state (original shape), and pressing member 35A moves downward (-z direction). As a result, the tip 36h of the valve 36A is accommodated inside the pressing member 35A without protruding from the lower end of the cylindrical body 35 n. In other words, the valve body 36p is formed to have such a height that the tip 36h of the valve 36A protrudes from the lower end of the cylindrical body 35n when the elastic member 37 is deformed, and the tip 36h of the valve 36A does not protrude from the lower end of the cylindrical body 35n when the elastic member 37 is not deformed.

Next, replacement of the filter element 20A of the reflux filter 2 will be described. Since the filter member 21 is clogged when the filtration is repeated, the pressure of the space S1 is increased, and thus the filter element 20A is replaced. When replacing the filter element 20A, the working machine is stopped, and the cover assembly 32A is removed from the flange portion 31A. Since the diameter of the opening 102A and the diameter of the hole 31b are larger than the diameter of the filter element 20, the filter element 20A can be replaced by simply removing the cover assembly 32A, and maintenance is easy.

Further, since the detection unit 63 is provided in the flange portion 31A, the detection unit 63 remains attached to the tank 100A side when the filter element 20 is replaced. Therefore, additional work such as removing the wiring provided in the detection unit 63 is not required, and maintenance is easy.

After the used filter element 20A is taken out, an unused filter element 20A is inserted into the housing 10. Thereafter, the cover assembly 32A is attached to the flange portion 31A. As shown in fig. 10 and 12, since the cut-out portion 35f is formed at the front end of the positioning portion 35e, the plate 24A is guided to the outside of the positioning portion 35e, and the plate 24A and the pressing member 35A are automatically positioned. Therefore, even when the operator performs a rough operation such as replacing the plurality of filter elements 20A at a time, the cover assembly 32A can be easily attached.

As shown in fig. 11 and 12, when the cover assembly 32A is removed from the flange portion 31A, the elastic member 37 is restored, and the tip 36h is thereby accommodated inside the pressing member 35A. This enables the cover assembly 32A removed to be placed on the upper surface 102A of the tank 100A, for example, thereby improving maintainability.

According to the present embodiment, the height of the pressing member 35A is reduced, the columnar portion 33c is inserted into the hollow portion of the flange portion 31A, and the flow path 61A is provided in the columnar portion 33c, so that the size of the reflux filter 2 can be reduced. In particular, by providing the columnar portion 33c in the plate-shaped portion 33A, the lid body 30A can be lowered (lowered).

Further, according to the present embodiment, since the pressing member 35A is formed by providing the cylindrical body 35n on the pressing portion main body 35m, the pressing member 35A can be configured simply.

While the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to the embodiments, and design changes and the like are also included without departing from the scope of the present invention. For example, the above-described embodiments have been described in detail to explain the present invention in an easily understandable manner, but the present invention is not necessarily limited to having all of the described configurations. Further, a part of the configuration of the embodiment may be replaced with the configuration of another embodiment, and the configuration of the embodiment may be added, deleted, replaced, or the like with respect to another configuration.

"substantially" is a concept including not only strictly the same cases but also errors and variations to the extent that identity is not lost. For example, the "substantially cylindrical shape" is a concept including not only a case of being strictly cylindrical but also a case of being equally viewable with a cylindrical shape, for example. For example, when only the terms orthogonal, parallel, and uniform are used, the terms include not only the cases of being strictly orthogonal, parallel, and uniform, but also the cases of being substantially parallel, substantially orthogonal, and substantially uniform.

The term "vicinity" refers to a region including a certain range (which can be arbitrarily specified) in the vicinity of a reference position. For example, the term "near the end" refers to a certain range of the area near the end, and is a concept that may or may not include the end.

Description of reference numerals:

1. 2: reflux filter

10: shell body

11: side surface

12: inlet port

13: bottom surface

15: outflow part

20. 20A: filter element

21: filter element

22: outer cylinder

23: inner cylinder

24. 24A, 25: board

26: sealing member

30. 30A: cover body

31. 31A: flange part

31 a: hole(s)

31b, 31c, 31d, 31 f: hole(s)

31 e: peripheral surface

31 g: convex part

32. 32A: cover assembly

33. 33A: plate-shaped part

33 a: hole(s)

33 b: concave part

33 c: cylindrical part

34. 34A: insertion part

35. 35A: pressing member

35 a: cylindrical part

35 b: plane part

35c, 35 e: positioning part

35d, 35 f: cut-out part

35 g: plane part

35 h: cylindrical part

35 i: flange part

35 j: sealing member

35 m: pressing part main body

35 n: cylindrical part

36. 36A: valve with a valve body

36 a: valve rod

36b, 36 o: valve core

36c, 36 p: valve body

36 d: elastic member

36e, 36 q: fixing part

36f, 36g, 36 k: hole(s)

36 h: front end

37: elastic member

38. 39: sealing member

61. 61A: flow path

63: detection part

100. 100A: pot for storing food

101: bottom surface

101 a: outflow part

102. 102A: upper surface of

102 a: opening part

102 b: thick wall part

102 c: mounting member

103: side surface

104: inflow part

105: a partition plate.

Claims

1. A filter device is provided in a tank having an opening on the upper surface,

the filter device is characterized by comprising:

a substantially bottomed cylindrical case provided inside the tank;

a filter element provided inside the housing and having a filter member of a substantially cylindrical shape and an upper plate provided at an upper end of the filter member;

a lid body which is provided on the upper side of the tank so as to cover the opening portion, and which has a substantially cylindrical flange portion provided detachably on the tank, and a cover assembly provided detachably on the flange portion; and

a detection portion provided to the flange portion,

the aperture of the flange portion has a diameter larger than the diameter of the filter element,

a hole for the detection portion is formed on the outer peripheral surface of the flange portion toward the radial inner side,

the cover assembly has a substantially plate-shaped portion provided on the flange portion so as to cover the hollow portion of the flange portion, and an insertion portion provided on the plate-shaped portion and inserted into the housing,

a pressing member having a substantially annular flat surface portion is provided at an end of the insertion portion opposite to the plate-shaped portion,

a substantially annular sealing member is provided between the upper plate and the pressing member.

2. The filter device of claim 1,

the cover assembly has an elastic member and a valve, both ends of the elastic member are provided to the plate-shaped portion and the pressing member, the valve is provided to the plate-shaped portion,

the valve has a substantially cylindrical valve body provided in the plate-like portion,

the pressing member is provided movably relative to the valve body,

the elastic member deforms when the cover assembly is attached to the flange portion, so that the flat surface portion presses the filter element,

the valve body is formed to have the following height: the front end of the valve does not protrude from the pressing member when the elastic member is undeformed, and the front end of the valve protrudes from the pressing member when the elastic member is deformed.

3. The filter device of claim 2,

a first seal member is provided between the cap assembly and the flange portion,

a second sealing member is provided between the valve body and the pressing member,

the second sealing member is deformed by a smaller amount than the first sealing member, or the first sealing member is deformed by substantially the same amount as the second sealing member and the second sealing member has a hardness softer than the first sealing member.

4. A filter device according to claim 2 or 3,

the pressing member is movable in the up-down direction along the outer peripheral surface of the valve body and movable in a manner inclined with respect to the valve body,

a positioning portion having a substantially cylindrical shape is provided on an outer peripheral surface of the pressing member so as to protrude downward,

the outer peripheral surface of the upper plate is provided along the inner peripheral surface of the positioning portion,

the front end of the positioning part is notched so that the height of the inner peripheral surface is low and the height of the outer peripheral surface is high.

5. A filter device according to claim 2 or 3,

a positioning portion having a substantially cylindrical shape is provided in the pressing member so as to protrude downward,

the inner peripheral surface of the upper plate is provided along the outer peripheral surface of the positioning portion,

the front end of the positioning part is notched so that the height of the outer peripheral surface is low and the height of the inner peripheral surface is high.

6. A filter device according to any one of claims 2 to 5,

the pressing member includes a pressing portion main body having a substantially cylindrical portion and a substantially annular plate portion provided on an outer side of the cylindrical portion, and a tubular body provided on a lower side of the pressing portion main body,

the cylindrical portion is provided along an outer peripheral surface of the valve body,

the annular plate portion has the planar portion.