JPH08299736A - Air filter - Google Patents

Abstract

PURPOSE: To provide an air filter enabling sure removal of solids, while air permeation resistance is reduced, and having flexibility. CONSTITUTION: A filter main body 2 consists of a tube constituting a part of a prescribed air pressure circuit and many porous hollow fiber membranes 5 each formed with many fine pores making the outside surface and the inside surface of the hollow pore communicate with each other are bundles in the main body 2. This air filter 1 has filter elements 3 housed in the main body 2 with the membranes 5 faced to the opening part 2a of one side of the filter main body 2 while being arranged. The filter element 3 is fixed to the opening part 2a of the filter main body 2 with a potting resin 4. Also the filter main body 2 is composed of a flexible material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air filter for removing solids contained in compressed air as a working fluid flowing in a pneumatic circuit to clean the solids.

[0002]

2. Description of the Related Art When operating an actuator such as a pneumatic cylinder, compressed air discharged from an air pressure source such as a compressor is supplied to the actuator by using pneumatic equipment such as a pressure control valve, a direction control valve and a speed control valve. Guides are connected by pneumatic lines to form various pneumatic systems or pneumatic circuits.

Since compressed air flowing in the circuit contains solids such as dust and scale, an air filter is used in the pneumatic circuit to remove these solids. Further, at negative pressure, an air filter is used to prevent dust from entering a vacuum pump or the like.

As the filter element, a sintered metal, a sintered resin or the like is used, and the solid content is captured by the pores of the filter element.

[0005]

In order to improve the filtering accuracy which is the essential function of the filter, it is necessary to reduce the diameter of the pores, but in the filter element such as the above-mentioned sintered resin, the inner diameter of the pores is There is a limit to making it small,
There was a problem that the filtration accuracy could not be significantly improved.

Even if the diameter of the pores can be made small, it is difficult to make the filter element such as a sintered metal in a size that can be manufactured. The ratio of filtration area is small. This causes the problems of shortening the durability of the filter element and increasing the ventilation resistance.

Further, these are hard filter elements, and an air filter incorporating such a filter element cannot be bent, and can follow the flexibility of a tube forming a part of a pneumatic circuit. There wasn't.

Therefore, an object of the present invention is to provide an air filter which can reliably remove solid matter while reducing ventilation resistance.

Another object of the present invention is to provide an air filter having flexibility.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0011]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

That is, the air filter according to the present invention is
A filter main body made of a tube forming a part of a predetermined pneumatic circuit, and a large number of porous hollow fiber membranes in which a large number of pores that connect the outer surface and the inner surface of the hollow hole are formed are bundled together. The filter element is arranged in the filter body so as to be aligned with one of the openings. The filter element is fixed to the opening of the filter body by a fastening member.

The filter body of such an air filter is preferably made of a soft material. The filter element may also be arranged in both openings of the filter body. In addition, the filter body can have an inner diameter at a portion where the filter element is arranged larger than that at other portions.

[0014]

According to the air filter having the above-mentioned structure, since the porous hollow fiber membrane is used as the filter element, the average diameter of the pores is made small and the porous hollow fiber is larger than the size of the filter element. Since the total area of the outer surface of the thread film can be increased, the filtration accuracy can be significantly improved and the ventilation resistance can be reduced.

Since the tube is the main body of the filter,
If the filter body is made of a soft material, it is possible to provide an air filter that is highly flexible and has good handling.

By making the inner diameter of the portion of the filter body where the filter element is arranged larger than the inner diameters of the other portions, the amount of the porous hollow fiber membrane accommodated is expanded and the filtration area of the filter element is further increased. be able to.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. In all the drawings for explaining the embodiments, the same members are designated by the same reference numerals, and the repeated description thereof will be omitted.

(Embodiment 1) FIG. 1 is a sectional view showing an air filter which is an embodiment of the present invention, FIG. 2 is an enlarged perspective view of a main portion of the air filter, and FIG. 3 is an opening of a porous hollow fiber membrane. 4 to 6 are sectional views showing a part of the side, and FIG. 4 to FIG. 6 are sectional views showing examples of usage modes of the air filter of FIG. 1, FIG. 7 and FIG.
2A and 2B are schematic views respectively showing an example of a pneumatic circuit using the air filter of FIG.

The air filter 1 of this embodiment shown in FIG.
The filter main body 2 is formed by a tube that constitutes a part of the pneumatic circuit as shown in FIGS. 7 and 8. The filter body 2 is made of a flexible urethane tube,
The filter element 3 is arranged so as to face one opening 2a. The filter element 3 is fixed by a potting resin (fastening member) 4. Therefore, the air filter 1 can be bent in a desired direction by the filter body 2 made of a soft material. Then, in the fluid that has flowed into the filter body 2 through the opening 2a, the solid content contained therein is removed by the filter element 3 and discharged. The tube that is the filter body 2 is made of a hard material such as nylon tube,
Alternatively, a steel pipe such as metal or other resin may be used. Further, the filter element 3 may be arranged in both openings 2a (the other opening is not shown).

The filter element 3 in the filter body 2
As shown in FIG. 2, is formed by bundling a large number of porous hollow fiber membranes 5, which are each folded in two. For example, the porous hollow fiber membrane 5 made of polyethylene, polypropylene, or the like, as shown in an enlarged view of FIG.
A large number of pores 5b that connect the inner surface and the outer surface of a are formed. The outer diameter D of each porous hollow fiber membrane 5 is, for example, about 0.38 mm, and the average pore diameter of the pores 5b is, for example, about 0.1 μm. The total area of the inner surfaces of the porous hollow fiber membrane 5 is the filtration area of the filter element 3. The length of the porous hollow fiber membrane 5 can be freely set in consideration of the life of the filter element 3.

Here, even if the fluid flows in the reverse direction, that is, from the opening opposite to the opening 2a, into the filter main body 2 and is discharged from the opening 2a, the solid content contained is determined by the filter element 3. To be removed. In addition, in the flow in this direction, the total area of the outer surfaces of the porous hollow fiber membranes 5 becomes the filtration area of the filter element 3, and the filtration area becomes larger than that in the above case, which is desirable for use.

As shown in FIG. 1, the respective porous hollow fiber membranes 5 are arranged so that both ends thereof are on the side of one opening 2a of the filter body 2.

When such an air filter 1 is incorporated into a pneumatic circuit, the fluid flowing in from one opening 2a is discharged from the other opening, and at this time, if the fluid contains solid matter. If the pore size is 0.1 μm or more, the particles are captured by the filter element 3. As a result, only purified air is discharged. Therefore, by arranging the air filter 1 shown in this embodiment immediately before the fluid pressure operating device such as the pneumatic cylinder or the actuator in the pneumatic circuit, clean air is supplied to the pneumatic operating device. As described above, the air filter 1 may be installed reversely so that the fluid is discharged from the opening 2a.

As shown in FIGS. 4 to 6, the air filter 1 is used by connecting one end thereof to, for example, a joint.

The joint 6 shown in FIGS. 4 and 5 has one opening 7a of a resin housing 7 formed in a substantially L shape.
The lock pin 8 is attached to the filter body 2
Are connected in a state of being locked to this lock pin 8 which is elastically deformed radially outward. An annular seal member 9 is provided along the inner circumference of the opening 7a to seal the space between the filter body 2 and the housing 7 that are connected to each other to prevent air leakage. A release ring 10 that deforms the lock pin 8 radially outward is provided on the outer side of the lock pin 8.
If the lock pin 8 is pushed inward, the lock pin 8 is deformed
Are removed from the joint 6. A metal connecting portion 11 is provided in the other opening 7b through a seal member 12 to form the housing 7
Attached to. A sealant 13 made of, for example, a fluororesin is applied to the outer peripheral portion of the screw on one end side of the tubular connecting portion 11, and this portion is screwed into a pipe (not shown). It is connected to the piping via.

In the case shown in FIG. 4, the filter element 3 is provided on the joint 6 side of the filter body 2 made of a tube. On the other hand, in the case shown in FIG. 5, it is provided on the side opposite to the joint 6, for example, immediately before the fluid pressure actuated device.
As described above, the connection configuration with the joint 6 may be such that the air filter 1 is located on the joint 6 side (FIG. 4) or on the side opposite to the joint 6 (FIG. 5).

In FIG. 6, the air filter 1 is attached to a fluid pressure operating device in which the one-touch joint 14 is built. The one-touch joint 14 is a body 15 of a fluid pressure operating device.
A lock pin 14a which is attached to a connecting port 16 formed in the front side and is elastically deformable outward in the radial direction;
Member 14b for sealing between the filter body 2 and the filter body 2
When the air filter 1 is inserted into the connection port 16, the air filter 1 is locked by the lock pin 14a.
Is automatically locked to the body 15 side. In FIG. 6, the filter element 3 is on the fluid pressure actuating device side, but it may be on the opposite side as in the case described above.

The air filter 1 of this embodiment is specifically used in a pneumatic circuit as shown in FIGS. 7 and 8.

In the case shown in FIG. 7, the laminated film 17 is an air pressure circuit for vacuum-packing the food, and on the path from the packing device 18 to the vacuum pump 19,
A vacuum valve 20 for releasing the vacuum state of the path as necessary, a liquid trap 21 for preventing moisture and odor in the laminated film 17 from entering the vacuum pump 19, and a vacuum degree adjusting valve 22 for adjusting the degree of vacuum of the circuit. The air filter 1 according to the present embodiment and the vacuum gauge 23 are arranged. In addition, in the case shown in FIG.
5 is a pneumatic circuit for vacuum-adsorbing and conveying 5, and on the path from the adsorption rubber 24 to the vacuum pump 19, the air filter 1, the vacuum valve 20, the check valve 26 according to the present embodiment,
A vacuum degree adjusting valve 22 and a vacuum gauge 23 are arranged.

As shown in the figure, the air filter of the present embodiment, which is integrated with the pipe line, is integrated with the pipe line instead of the conventional air filter (that is, the air filter having a filter housing and separate from the pipe line). By using 1, it is possible to improve the handling, and it is possible to install this not only in the fixed part of the conduit as shown in FIG. 7 but also in the movable part such as in the vicinity of the suction rubber 24 as shown in FIG. Become. Note that FIG.
And in FIG. 8, the air filter 1 is a vacuum pump 1.
Although it is used in the negative pressure circuit using 9, it is also possible to use it in the positive pressure circuit.

As described above, according to the air filter 1 of this embodiment, the porous hollow fiber membrane 5 is used as the filter element 3.
Since the average pore diameter of the pores 5b is made small as about 0.1 μm, the total area of the outer surface of the porous hollow fiber membrane 5 can be increased with respect to the size of the filter element 3. In addition, the ventilation resistance can be reduced and the filtration accuracy can be significantly improved.

Further, since the tube, which has been a simple piping medium in the past, is used as the filter body 2, the air filter 1 becomes compact, and further, the structure is simplified, so that space saving and cost reduction can be achieved. become.

Since the tube is used as the filter body 2, if the tube, that is, the filter body 2 is made of a soft material, the air filter 1 having a good flexibility and good handling can be obtained.

(Embodiment 2) FIG. 9 is a sectional view showing an air filter according to another embodiment of the present invention.

As shown in the figure, in the air filter 31, the inner diameter R ₁ of the opening 32a in which the filter element 3 of the filter body 32 is arranged is larger than the inner diameters R ₂ of other portions. Is. By forming the filter main body 32 in this way, the amount of the porous hollow fiber membrane 5 accommodated can be expanded, and the filtration area of the filter element 3 can be further increased.

Although the invention made by the present inventor has been concretely described above based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the tubes constituting the filter bodies 2 and 32 are not the single cylinder type as shown in this embodiment, but various types such as flat tubes, double tubes, multi-core tubes or electric signal line mixing tubes. It is possible to use the thing of. The use of these special tubes facilitates maintenance and support of the piping.

Further, in the case shown in the drawing, each porous hollow fiber membrane 5 is folded in two and the both ends of the filter body 2,
Although it is made to face the openings 2a, 32a of 32, one end may be closed and the other end may be made to face the openings 2a, 32a.

The average pore size of the pores 5b of the porous hollow fiber membrane 5 is not limited to the above-mentioned size, and various pore sizes can be set according to the particle size of the solid matter to be removed. Is.

[0040]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) That is, according to the air filter of the present invention, since the porous hollow fiber membrane is used as the filter element, the average pore size of the pores is made smaller and the size of the filter element is reduced. Since the total area of the outer surface of the porous hollow fiber membrane can be increased, the filtration accuracy can be significantly improved and the ventilation resistance can be reduced.

(2) Further, since the tube which is the piping medium is used as the filter body, the air filter becomes compact, the structure is simplified, and it is possible to save space and reduce cost.

(3) Since the tube is used as the filter body, various joints related to the tube which is the filter body can be used, and a flexible and quick pneumatic circuit can be constructed.

(4) Since the tube is used as the filter body, even if the fluid needs to be filtered suddenly, it can be dealt with without considering the installation space.

(5) Since the tube is used as the filter main body, if the filter main body is made of a soft material, it is possible to obtain an air filter which is rich in flexibility and good in handling.

(6). By making the inner diameter of the portion of the filter body where the filter element is arranged larger than the inner diameters of the other portions, the capacity of the porous hollow fiber membrane is expanded and the filtration area of the filter element is increased. Can be further increased.

[Brief description of drawings]

FIG. 1 is a sectional view showing an air filter according to a first embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a main part of the air filter of FIG.

3 is a cross-sectional view showing a part of an opening side of a porous hollow fiber membrane used in the air filter of FIG.

FIG. 4 is a cross-sectional view showing an example of how the air filter of FIG. 1 is used.

FIG. 5 is a cross-sectional view showing an example of how the air filter of FIG. 1 is used.

FIG. 6 is a cross-sectional view showing an example of how the air filter of FIG. 1 is used.

FIG. 7 is a schematic diagram showing an example of a pneumatic circuit using the air filter of FIG.

FIG. 8 is a schematic view showing an example of a pneumatic circuit using the air filter of FIG.

FIG. 9 is a sectional view showing an air filter according to a second embodiment of the present invention.

[Explanation of symbols]

1 Air Filter 2 Filter Body 2a Opening 3 Filter Element 4 Potting Resin (Fixing Member) 5 Porous Hollow Fiber Membrane 5a Hollow Hole 5b Pore 6 Joint 7 Housing 7a Opening 7b Opening 8 Lock Pin 9 Sealing Member 10 Release Ring 11 Connection part 12 Seal member 13 Sealing agent 14 One-touch joint 14a Lock pin 14b Seal member 15 Body 16 Connection port 17 Laminated film 18 Packing device 19 Vacuum pump 20 Vacuum valve 21 Liquid trap 22 Vacuum adjustment valve 23 Vacuum gauge 24 Adsorption rubber 25 Plate Work 26 Check Valve 31 Air Filter 32 Filter Body 32a Opening D Outer Diameter R ₁ Inner Diameter R ₂ Inner Diameter

Claims (4)

[Claims] 1. A bundle of a large number of porous hollow fiber membranes having a large number of fine pores for communicating an outer surface with an inner surface of a hollow hole and a filter main body made of a tube forming a part of a predetermined pneumatic circuit. And a filter element disposed in the filter body so as to be aligned with one opening of the filter body, and a fastening member for fixing the filter element to the opening of the filter body. And an air filter. 2. The air filter according to claim 1, wherein
An air filter, wherein the filter body is made of a soft material. 3. The air filter according to claim 1, wherein the filter element is arranged in both openings of the filter body. 4. The air filter according to claim 1, 2 or 3, wherein the filter body has an inner diameter larger at a portion where the filter element is arranged than at other portions. Air filter.