JPH0522014U - Saxion filter with magnet - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a suction filter with a magnet that facilitates the work of removing the magnetic substance adsorbed from the hydraulic oil by the magnet. [Structure] A filter case 10 made of a non-magnetic material,
Magnet 30 protruding into the internal space of the filter case
b, and a magnet cover 40 provided on the inner surface of the filter case and formed of a non-magnetic material to cover the magnet. The magnet 30b or the magnet cover is provided.
40 is removable from the filter case 10.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a suction filter with a magnet.

[0002]

[Prior Art]

 Suction filters are used, for example, in hydraulic circuits to remove impurities in hydraulic fluid. In addition to the functions described above for a normal suction filter, the suction filter with a magnet absorbs the magnetic substance in the hydraulic oil by the magnetic force of the magnet, and the magnetic substance in the hydraulic oil that is smaller than the filtration accuracy of the filter member is used in the hydraulic circuit. It has the function of preventing it from flowing inside. Therefore, the suction filter with magnet not only extends the life of the filter member but also the life of the hydraulic device in the hydraulic circuit. FIG. 2 shows a vertical section of a conventional suction filter with a magnet for a hydraulic circuit.

The filter case 10 is made of a non-magnetic material such as an aluminum alloy and has a substantially cylindrical shape. At the inner end of one opening functioning as the hydraulic oil inlet 12, the inner space of the filter case 10 is provided. A stored relief valve 14 is mounted. The other opening of the filter case 10 is closed by an end cap 18 via an oil seal 16. Here, the end cap 18 is also made of a non-magnetic material such as an aluminum alloy.

A cylindrical filter member 20 is arranged substantially concentrically with respect to the filter case 10 in the internal space of the filter case 10, and both ends of the filter member 20 have inner end surfaces 18 a of the end caps 18. It is supported via an oil seal 22 on the outer peripheral surface of the annular filter receiving groove 18b formed in the above and the cylindrical inner end portion 14a of the relief valve 14. The inner space of the filter member 20 is isolated from the outer region surrounding the filter member 20 in the inner space of the filter case 10 by the filter member 20 and oil seals 22 at both ends thereof.

A hydraulic oil outlet 24 is formed near the end cap 18 on the outer peripheral wall of the filter case 10, and is closed by an oil drain plug 26 near the relief valve 14 on the outer peripheral wall. An oil drain hole 28 is formed.

The end cap 18 has an indicator 29 connected to the hydraulic oil outlet 24 of the filter case 10. A magnet unit 30 protruding into the inner space of the filter member 20 is attached to the inner end surface 18a of the end cap 18 facing the hydraulic oil inlet 12 (that is, the relief valve 14) of the filter case 10. .. The magnet unit 30 includes a mandrel 30a and a plurality of annular magnets 30b concentrically held on the mandrel 30a in multiple layers, and one end of the mandrel 30a is fixed to the center of the inner end surface 18a of the end cap 18. ..

On the outer peripheral surface of the magnet unit 30, it has flowed into the internal space of the filter member 20 in the internal space of the filter case 10 via the hydraulic oil inlet 12 of the filter case 10 and the relief valve 14. The magnetic substance in the hydraulic oil (for example, metal powder generated in the hydraulic operating machine in the hydraulic circuit) is adsorbed as indicated by the chain double-dashed line 32.

The relief valve 14 causes the amount of hydraulic oil discharged from the working oil outlet 24 of the filter case 10 to fall below a predetermined value due to clogging of the filter member 20 (ie, the filter case 10 When the pressure of the working oil in the inner space of the filter member 20 in the inner space becomes higher than a predetermined value), the working oil flowing from the working oil inlet 12 into the inner space of the filter case 10 is filtered. It leads to an outer region surrounding the filter member 20 in the inner space of the space 10. By opening the relief valve 14 in this way, the amount of hydraulic oil discharged from the hydraulic oil outlet 24 of the filter case 10 is maintained at a predetermined value, and the hydraulic circuit in the hydraulic circuit malfunctions due to insufficient hydraulic oil. Is prevented.

[0009]

The conventional suction filter with a magnet having the above-described structure is periodically disassembled to replace the filter member 20 or the magnetic attraction on the outer peripheral surface of the magnet unit 30. The body 32 needs to be removed. The above-mentioned disassembly is performed by separating the end cap 18 from the filter case 10, and the magnet unit 30 is pulled out from the inner space of the filter case 10 while being fixed to the separated end cap 18. Then, the magnetic body 32 on the outer peripheral surface of the magnet unit 30 is wiped off with a clean cloth or the like.

Here, since the operating oil is also attached to the outer peripheral surface of the magnet unit 30, it is complicated to wipe the magnetic body 32 from the outer peripheral surface with a cloth or the like under the influence of the magnetic force of the magnet unit 30. However, if you apply force, hydraulic oil will be scattered from the outer peripheral surface, and it will contaminate the work place as well as the clothes and skin of the operator.

The present invention has been made under the above circumstances, and an object of the present invention is to provide a suction filter with a magnet that facilitates the work of removing a magnetic substance adsorbed from working oil by a magnet.

[0012]

[Means for solving the problem]

 The purposes as described above are: a filter case made of a non-magnetic material; a magnet protruding into the inner space of the filter case; a magnet formed on the inner surface of the filter case and made of a non-magnetic material. This can be achieved by a suction filter with magnet according to the present invention, which is provided with a covering magnet cover, and the magnet or the magnet cover is detachable from the filter case.

[0013]

[Action]

 The magnet projecting into the inner space of the filter case made of a non-magnetic material is provided on the inner surface of the filter case and is covered by the magnet cover made of a non-magnetic material. The magnetic substance in the fluid flowing into the inner space of the space is attracted to the outer peripheral surface of the magnet cover by the magnetic force of the magnet. By separating the magnet or the magnet cover that is detachable from the filter case from the filter case, the action of the magnetic force of the magnet on the magnetic substance adsorbed on the outer peripheral surface of the magnet cover can be eliminated. The magnetic substance on the outer peripheral surface of the magnet cover can be removed without being affected by the magnetic force of the magnet.

[0014]

【Example】

 Hereinafter, a suction filter with a magnet according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 (A) and 1 (B). This magnet-equipped suction filter is an improvement of the conventional magnet-equipped suction filter for the hydraulic circuit described above with reference to FIG. 3, and the same parts as those of the conventional magnet-equipped suction filter are designated by the same reference numerals. The detailed description thereof will be omitted.

In the suction filter with magnet according to the embodiment of the present invention, as shown in FIG. 1A, the end of the filter case 10 facing the hydraulic oil inlet 12 (that is, the relief valve 14). A magnet cover 40 protruding toward the hydraulic oil inlet 12 is formed at a portion surrounded by the filter member 20 on the inner end surface 18 a of the cap 18. The diameter of the base end of the magnet cover 40 is substantially equal to the inner diameter of the filter member 20, and the tip end of the magnet cover 40 is sharpened toward the hydraulic oil inlet 12. On the outer peripheral surface of the magnet cover 40, a plurality of grooves 40a extending from the distal end portion toward the proximal end are formed at equal intervals in the circumferential direction, as shown particularly well in FIG. There is.

The magnet cover 40 is provided with a magnet housing cavity 40 b that is open to the outer end surface of the end cap 18. The magnet unit 30 is inserted into the magnet housing cavity 40b, and the outer end 31 of the mandrel 30a of the magnet unit 30 is screwed into the entrance of the magnet housing cavity 40b.

In this embodiment, the magnet cover 40 is integrally formed with the end cap 18 and made of the same nonmagnetic material as the end cap 18, such as an aluminum alloy. However, the magnet cover 40 can be fixed to the inner end surface 18a of the end cap 18 in an oil-tight manner by a suitable known fixing means after it is formed of a non-magnetic material separately from the end cap 18. In this case, an opening corresponding to the opening of the magnet storage cavity 40b of the magnet cover 40 must be formed in the center of the end cap 18 in advance.

According to the idea of the invention, the outer shape of the magnet cover 40 is a cone or a pyramid whose tip portion is sharply sharpened like a needle tip or rounded like a hemisphere and sharpened with a relatively large curvature. It may be in the shape of a cylinder, or may be in the shape of a cylinder or a prism having a tapered shape in which the tip end is sharpened and the base end portion is widened toward the corresponding end portion of the inner peripheral surface of the filter member 20 as the distance from the hydraulic oil inlet 12 increases. In short, the magnet cover 40 may be set in a shape and a size that do not increase the flow resistance of the suction filter with magnet.

In the suction filter with magnet according to the embodiment of the present invention constructed as described above, the internal space of the filter member 20 in the internal space of the filter case 10 is inserted through the hydraulic oil inlet 12. A magnetic substance such as metal powder in the inflowing hydraulic oil is minute, and even a minute magnetic substance is indicated by a two-dot chain line 42 in the plurality of grooves 40a on the outer peripheral surface of the magnet cover 40 by the magnetic force generated by the magnet unit 30. It is sucked like this.

In the periodic inspection, the end cap 18 is separated from the filter case 10 with the tip of the magnet cover 40 facing downward, and then the filter member 20 is pulled out from the end cap 18 and the magnet cover 40. When the magnet unit 30 is pulled out from the magnet storage cavity 40b on a pan such as an oil pan, the magnetic force of the magnet unit 30 acts on the magnetic body 42 adsorbed on the outer peripheral surface of the magnet cover 40. Disappear. Since the residual magnetism does not remain in the magnet cover-40 and the end cap 18 which are made of a non-magnetic material, the magnetic body 42 adsorbed on the outer peripheral surface of the magnet cover 40 is the outer periphery of the magnet cover 40. The working oil adhering to the surface flows along the plurality of grooves 40a toward the tip of the magnet cover 40 and drops from the tip.

The plurality of grooves 40 a on the outer peripheral surface of the magnet cover 40 facilitates holding the magnetic body 42 on the outer peripheral surface when the end cap 18 is separated from the filter member 20, and the magnetic body 42. Prevents the oil from spilling into the inner space of the filter member 20 inside the oil seal 22 above the filter member 20.

Next, a suction filter with a magnet according to another embodiment of the present invention will be described in detail with reference to the attached FIG. This magnet-equipped suction filter is also an improvement of the conventional magnet-equipped suction filter for the hydraulic circuit described above with reference to FIG. 3, and moreover, the magnet-equipped suction filter according to the embodiment described above with reference to FIG. It has a lot of common structural members with the operation filter. Therefore, the same parts as those of the conventional suction filter with a magnet and the suction filter with a magnet according to the embodiment described above are designated by the same reference numerals, and the detailed description thereof will be omitted.

In this alternative embodiment, one end of the mandrel 30a of the magnet unit 30 is fixed to the center of the inner end surface 18a of the end cover 18, and is formed of a non-magnetic body separately from the end cap 18. The open end of the magnet cover 40 is screwed onto the inner end surface 18 a of the end cap 18. The magnet cover 40 can be detachably fixed to the inner end surface 18a of the end cap 18 by a suitable known fixing means such as a screw.

In the periodic inspection, the end cap 18 is separated from the filter case 10 with the tip of the magnet cover 40 facing downward, and then the magnet cover 40 is put into the inner end surface of the end cap 18 in the same state. When separated from 18a, the magnet unit 30 can be removed from the magnet storage cavity 40b of the magnet cover 40, whereby the magnetic force of the magnet unit 30 is attracted to the outer peripheral surface of the magnet cover 40. No effect on 42. Since no residual magnetism remains on the magnet cover 40 formed of a non-magnetic material, the magnetic material 42 adsorbed on the outer peripheral surface of the magnet cover 40 adheres to the outer peripheral surface of the magnet cover 40. The working oil flows along the plurality of grooves 40a toward the tip of the magnet cover-40 and drops from the tip.

In the above-described one embodiment and the above-described another embodiment, the magnet cover 40 having a pointed end is opposed to the hydraulic oil inlet 12 (that is, the relief valve 14) of the filter case 10. The inner end surface 18 a of the cap 18 projects toward the hydraulic oil inlet 12. For this reason, the hydraulic oil flowing from the hydraulic oil inlet 12 into the internal space of the filter case 10 is promptly guided to the outside in the radial direction by the magnet cover 40 with a small resistance as described above. The stagnation of the hydraulic oil flow in the internal space is prevented.

As a result, when the suction filter with magnet is incorporated in the hydraulic circuit including the variable displacement pump and the variable displacement pump is used at a low flow rate, or when it is incorporated in the hydraulic circuit including the constant displacement pump, the rating of this hydraulic circuit is increased. Even when the rated flow rate is larger than the flow rate, the minute bubbles mixed in the hydraulic oil do not stay in the internal space, and the accumulated minute bubbles in the hydraulic circuit It is possible to effectively prevent the noise from flowing out to the pump and causing abnormal noise in the pump or causing vibration or damage to the pump.

Further, since the magnet cover 40 reduces the internal volume of the suction filter with magnet, the amount of hydraulic oil in the oil suction pipe from the oil tank to the pump is reduced, and the resistance applied to the pump at the time of starting the pump is reduced. It also brings benefits.

[0028]

[Effect of the device]

 In the suction filter with a magnet of the present invention configured as described above in detail, the magnetic substance that has flowed in in the state of being mixed with the fluid in the inner space of the filter case and is attracted to the outer peripheral surface of the magnet cover by the magnetic force of the magnet is , The magnet or magnet cover that is detachable from the filter case is separated from the filter case, and the action of the magnetic force of the magnet on the magnetic substance adsorbed on the outer peripheral surface of the magnet cover is eliminated, thereby It can be removed without being affected by the magnetic force of the magnet from the outer peripheral surface of the cover.

Therefore, the work of removing the magnetic substance adsorbed on the magnet cover from the hydraulic oil by the magnet can be easily performed without requiring a large force, and the magnetic substance can be removed from the top of the magnet cover during the removing work. Prevents the hydraulic oil from splashing and contaminating the work place as well as the clothes and skin of the worker.

[Brief description of drawings]

FIG. 1 shows a suction filter with a magnet according to an embodiment of the present invention, FIG.
And (B) is a front view of the magnet cover in the direction of arrow B of (A).

FIG. 2 is a vertical sectional view of a suction filter with a magnet according to another embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view of a conventional suction filter with a magnet for a hydraulic circuit.

[Explanation of symbols]

10 ... Filter case, 12 ... Hydraulic oil inlet, 14 ... Relief valve, 16 ... Oil seal, 18 ... End cap, 18
a ... inner end face, 18b ... filter receiving groove, 20 ... filter member, 22 ... oil seal, 24 ... hydraulic oil outlet, 26 ...
Oil drain plug, 29 ... Indicator, 30 ... Magnet unit, 30a ... Mandrel, 30b ... Magnet, 31 ... Outer end portion, 40 ... Magnet cover, 40a ... Groove, 40b ...
Magnet storage cavity, 42 ... Magnetic body.

Claims (5)

[Scope of utility model registration request] 1. A filter case made of a non-magnetic material; a magnet projecting into an inner space of the filter case; a magnet provided on an inner surface of the filter case and made of a non-magnetic material to cover the magnet. A suction filter with a magnet, comprising a magnet cover; and the magnet or the magnet cover being detachable from the filter case. 2. The magnet cover is integrally formed with the filter case and has a cavity opened to the outer surface of the filter case, and the magnet has the outer surface in the cavity of the magnet cover. The suction filter with a magnet according to claim 1, wherein the suction filter is attached detachably from the side. 3. The magnet cover is attachable to and detachable from the inner surface of the filter case, and the magnet is attached to the inner surface of the filter case and is stored in the inner space of the magnet cover. The suction filter with a magnet according to claim 1, wherein 4. The magnet cover is a filter case.
The suction filter with a magnet according to claim 1, characterized in that the suction filter with a magnet is formed by a projection that protrudes toward the fluid inlet and has a pointed protruding end at a portion of the inner surface of the cloth facing the fluid inlet. 5. The suction filter with a magnet according to claim 4, wherein a plurality of grooves extending from the protruding end toward the base end are formed on the outer surface of the protrusion.