JP3418536B2 - filter - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter that can be installed in a piping system such as an air system or a water system to remove impurities such as dust and oil.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional in-line type filter which can be attached to a piping system of an air supply system or a water supply system. Each of these filters 1 has a cylindrical housing 2 in which a cylindrical filter element 11 is coaxially housed along the central axis of the housing 2. These filters 1
The housing 2 is divided into an upper housing 3 and a lower housing 4 so that the filter element 11 can be replaced, and an inflow nozzle 5 and a discharge nozzle 6 are provided in the upper housing 3 connected to the pipe. Has been. Further, in order to confirm the performance of the filter 1, the pressure difference between the inflow side and the discharge side can be measured,
A nozzle 7 for connecting a differential pressure gauge is provided.

The filter element 11 is formed by cylindrically molding a material for filtration (filter material) such as hollow fiber, and has a hollow portion 12 inside. The filter 1 is capable of filtering a press-fitted fluid such as air or water from the outer peripheral side 13 of the filter element 11 and discharging the filtered fluid from a discharge nozzle 6 connected to the hollow portion 12. Therefore, the upper housing 3 is provided with a connecting pipe portion 8 that connects the discharge nozzle 6 and the filter element 11. The filter element 11 is attached to the connection port 8a of the connection pipe portion 8 with the tension bolt 9
The fluid that has been fixed and has been filtered out flows out from the discharge nozzle 6.

A filter 1a shown in FIG. 5 (a) is a component in which a housing 2 and a connecting pipe portion 8 are press-molded, and these are welded to assemble the filter 1. On the other hand, the filter 1b shown in FIG. 5 (b) is a die cast product such as aluminum, and the connecting pipe portion 8 is formed as a part of the structure of the upper housing 3 during casting.

[0005]

Such an in-line type filter requires a small mounting space,
Since it can be easily incorporated into a piping system, it is often used to remove impurities such as dust and oil in a fluid flowing through an air system or a water system. Therefore, such filters are small, have low pressure loss, and
It is desirable to be able to supply reliable products at low cost. In the filter 1a shown in FIG. 5 (a), since the bent tube is attached to the pressed housing 3 as the connecting tube portion 8, the frictional resistance with the fluid is small and the pressure loss is not so high. However, since the curved pipe is attached to the inside of the housing 3 in accordance with the discharge nozzle 6, the assembly is not easy, and a dedicated jig is required for accurate assembly. Therefore, the manufacturing cost is high.

On the other hand, the filter 1b shown in FIG.
Since the connecting pipe portion 8 is incorporated in the die-cast upper housing 3, the assembly is easy and the manufacturing cost is low. However, since it is a die-cast processed product, the inner surface roughness of the connecting pipe portion 8 is large and the frictional resistance with the fluid is large. Further, since the connecting pipe portion 8 is formed by casting, the wall thickness also becomes large, so that the cross-sectional area of the connecting pipe portion 8 becomes small. Therefore, it is difficult to reduce the pressure loss inside the filter. It is also possible to machine the cast upper housing 3 to reduce the inner surface roughness, but the processing cost for that increases the manufacturing cost.

Further, in these filters, it is necessary to periodically replace the filter element 11 in order to keep the pressure loss within an appropriate numerical value. Therefore,
Easy maintenance is also important. In the conventional filters 1a and 1b, when the filter element 11 is replaced, the tension bolt 9 needs to be removed or the filter element 11 needs to be removed from the tension bolt, so that a maintenance space is required to pull the lower housing 4 straight down. Is.

Further, in these filters, since the filter element 11 is fixed to the connection port 8a by the tension bolt 9, the entire load of the filter element 11 is applied to the connection port 8a. Therefore, it is difficult to stably hold the filter element 11, and in particular, in a filter capable of accommodating the filter element 11 having a long overall length and a wide filtration area, the connection pipe portion 8 has a large load due to pressure fluctuation of the fluid. It is essential to take measures such as increasing the strength of. For this reason, the space of the connecting pipe portion 8 or the housing 2 becomes small, the pressure loss increases, and the product cost increases. Also, if the tension bolt 9 is thickened to increase the connection strength of the filter, the hollow portion 1
Since the cross-sectional area of 2 becomes small, this causes an increase in pressure loss.

In view of these problems, it is an object of the present invention to provide a filter which is small in size, has a small pressure loss, is highly reliable, and can be supplied at a low cost. Another object of the present invention is to provide a filter that can be easily maintained and whose filter element can be easily attached and detached.

[0010]

Therefore, in the filter of the present invention, the filter element and the connecting pipe are coaxially connected to each other so that they can be fixed by being sandwiched between the upper housing and the lower housing. That is, in the filter according to the present invention, which is capable of accommodating a tubular filter element having a hollow inside in a tubular housing that can be divided into upper and lower parts in a substantially coaxial manner, a tubular connecting pipe connected to the inside of the filter element. The upper joint wall of the housing is in contact with the upper end of the connecting pipe, and the upper joint structure is provided so that the connecting pipe can be arranged substantially coaxially in the housing. The lower end wall of the housing is in contact with the lower end of the filter element. Then, a lower joint structure that allows the filter element to be arranged in the housing substantially coaxially is provided.Furthermore, the lower end of the connecting pipe contacts the upper end of the filter element, and the connecting pipe and the filter element are connected substantially coaxially. A possible connection structure is provided.

In the filter of the present invention, the filter element coaxially connected to the connecting pipe by the connecting structure has the upper joining structure provided on the upper wall of the upper housing and the lower joining structure provided on the lower wall of the lower housing. The structure fixes it coaxially within the housing. Therefore, the filter element can be fixed in the housing without using the tension bolt. Therefore, at the time of maintenance, the filter element can be removed laterally or obliquely with respect to the connection pipe, so that it is not necessary to pull out the lower housing downward, and the maintenance space can be greatly reduced. Further, since the filter element is mounted so as to be sandwiched between the housing from above and below, the mounting strength is high and the durability against the pressure fluctuation of the fluid is also high. In particular, even in a filter including a long filter element, since the filter element can be supported at both ends, it is possible to prevent the occurrence of vibration and prevent the element from being broken.

Further, the connecting pipe is also a simple tubular member that can be attached to the upper joint structure of the upper end wall of the upper housing, and since it is not necessary to independently support the load of the filter element, the degree of freedom in shape is high. Increase. Therefore, the connecting structure can be made smaller in diameter than the other portions of the connecting pipe, a large cross-sectional area of the main portion of the connecting pipe can be secured, and the pressure loss in the connecting pipe can be reduced. Furthermore, since it has a simple tubular shape, it can be manufactured by drawing, and by drawing the connecting pipe from a stainless steel plate,
It is possible to provide a highly reliable filter with a smooth surface and a small pressure loss. Further, since the surface can be made smooth, it becomes possible to use the lower end of the connecting pipe as a sealing surface in contact with the filter element.

Further, in the filter of the present invention, since the space occupied by the tension bolt is eliminated, it is possible to secure a wide flow passage, and also in this respect, the pressure loss can be reduced.

When the connecting pipe is attached to the upper housing of the filter of the present invention, it is only necessary to align the upper end of the connecting pipe with the upper joint structure provided on the upper end wall, so that the positioning is very simple and the assembling work is easy. Therefore, it is possible to supply low-cost and highly reliable products. Furthermore, since the filter of the present invention has a simple structure in which the cylindrical connecting pipe vertically connected coaxially and the filter element are housed in the housing, the filter can be supplied at a lower cost. Further, the filter of the present invention has higher reliability because it has no parts that may be worn or damaged like tension bolts.

As the upper joining structure, various structures can be adopted such that the upper end wall has such a diameter that the connecting pipe can be inserted therein. A structure that engages with the upper end of the connecting pipe, such as fitting the upper end of the connecting pipe by providing unevenness or steps on the upper end wall and conversely fitting the upper end of the connecting pipe into the upper connecting structure of the upper end wall If adopted, the joint location will be clear and easy to assemble. Further, if the connecting structure is a structure that engages with the upper end of the filter element and the lower joint structure is such that the lower end of the filter element hits and is positioned, it becomes easy to replace the filter element.

Further, in the present invention, the fluid connected to the connecting pipe
The connecting nozzle for discharge or inflow is installed so as to penetrate the outer peripheral wall of the housing and the outer peripheral wall of the connecting pipe.
I am trying. In this case, for fluid inflow or discharge
It is also possible to provide the connection nozzles for discharging and flowing out the fluid at positions facing each other, by mounting the connection nozzles of (3) so as to penetrate only the outer peripheral wall of the housing.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic structure of an air filter 10 according to the present invention by using a cross section. The air filter 10 of this example has a cylindrical housing 2 that can be divided into an upper housing 3 and a lower housing 4,
A cylindrical filter element 11 is coaxially housed inside the housing 2. The connecting portions 15 of the upper housing 3 and the lower housing 4 are connected to each other using a band 16 and a packing 17 so as to seal the inside. The filter element 11 is made of a filter material formed into a cylindrical shape, and air (air) is supplied from the outer peripheral surface 13 to the hollow interior 12 to obtain filtered air.

Inside the filter 10 of this embodiment, a cylindrical filter element 11 and a cylindrical connecting pipe 20 connected to the inside 12 of the filter element 11 are housed coaxially in a vertically connected manner. The filter element 11 and the connecting pipe 20 in the housing 3 and the lower housing 4
It is assembled so that it is sandwiched.
At the center of the upper end wall 3a of the upper housing 3, the connecting pipe 2
An annular step portion 31 that engages with the upper end 21 of 0 is formed so that the upper end 21 of the connecting pipe 20 fits inside the step portion 31 and the connecting pipe 20 is set coaxially inside the housing 2. It has become. An annular support member 35 is attached to the lower end 11a of the filter element 11, and the lower end 36 of the support member 35 contacts the central portion of the lower end wall 4a of the lower housing 4. The lower end wall 4a of this lower housing is processed into a shape centered on an axis such as a spherical surface or a cone. When the lower end 36 of the support member 35 hits the lower end wall 4a, the filter element 11 is coaxial with the inside of the housing 2. Is set to. Further, the lower end 22 of the connecting pipe 20 is formed into an annular shape having a smaller diameter than the upper cylindrical body portion 23 and engaging with the inside 12 of the filter element 11.
The filter element 11 can be connected to the connecting pipe 20 by inserting the filter element 11 into the upper end 11b of the filter element 11.

Further, the upper housing 3 has a peripheral wall 3b.
The inflow nozzle 5 and the discharge nozzle 6 are attached so as to penetrate through, and the discharge nozzle 6 further penetrates the cylindrical portion 23 of the connection pipe 20 and is connected to the inside 12 of the filter element 11. Further, a nozzle 7a for detecting the pressure inside the filter element 11 is attached to the center of the upper end wall 3a of the upper housing 3, and another nozzle for detecting pressure attached to the peripheral wall 3b of the upper housing 3 is attached. It is connected to a differential pressure gauge together with the nozzle 7b so that the differential pressure of the filter element 11 can be monitored.

Further, a drain nozzle 41 is attached to the center of the lower end wall 4a of the lower housing 4, and water or oil separated from the inflowing air inside the housing 2 is discharged to the outside through the drain nozzle 41. You can do it. For this reason, the lower end 36 of the support member 35 attached to the lower end 11a of the filter element 11 facing the lower end wall 4a has an intermittent structure, and drain or the like solidified on the peripheral wall 4b of the housing causes the support member 35 to move. It passes through and reaches the drain nozzle 41. On the other hand, the filter element 1 of the support member 35
On the side of 1, there is provided a continuous annular member 37 and a sealing plate 38 for hitting the end 11a of the element 11 and sealing the interior 12.

FIG. 2 shows a state in which the upper housing 3 and the lower housing 4 are vertically disassembled. In the air filter 10 of this example, since the upper housing 3 is connected and fixed to piping such as an air supply system, the upper housing 3
The lower housing 4 can be removed to replace the internal filter element 11. The connection pipe 20 is fixed to the upper housing 3 by vacuum brazing, and when the housing 2 is disassembled up and down, only the filter element 11 is detached and can be taken out. Further, the upper end 11b of the filter element 11 is connected to the connecting pipe 20.
When the upper housing 3 and the lower housing 4 are connected to each other by fitting the lower end 22 of the upper housing 3 and the lower housing 4, the lower end 36 of the annular member 35 of the filter element 11 is connected to the lower end wall 4 of the lower housing 4.
The filter element 11 is pressed against a and can be attached to a predetermined position inside the housing 2, that is, a substantially coaxial position. As described above, in the filter 10 of this example, since the filter element 11 is sandwiched and fixed by the lower end 22 of the connecting pipe 20 and the lower housing 4, it is not necessary to fix the element 11 with the tension bolt unlike the conventional filter. Therefore, the replacement of the element 11 can be performed very easily.

The connecting pipe 20 of this embodiment has a relatively simple shape mainly composed of the cylindrical body portion 23 and the annular lower end 22 extending downward as described above. Therefore, the stainless steel plate can be formed by drawing, and the connecting pipe 20 having a thin and smooth surface can be supplied at a low price. Therefore, the lower end 22 to be inserted into the filter element 11 can also be formed with a surface having a small roughness, so that the outer surface 22a of the lower end 22 can be used as a sealing surface. Therefore, the filter 1 of this example
In 0, the O-ring 14 is attached to the upper end 11b of the element 11 with the inner side facing, and the lower end 22 of the connecting pipe 20 is directly inserted into the upper end 11b to obtain a high sealing performance.

FIG. 3 schematically shows how the connecting pipe 20 is attached to the upper housing 3 of the filter 10 of this example. The cylindrical connecting pipe 20 can be positioned at a predetermined place by setting the upper end 21 of the connecting pipe 20 so as to fit into the step portion 31 provided on the upper end wall 3a of the upper housing 3. Therefore, a jig or the like for attachment is unnecessary, and the connecting pipe 20 can be easily and accurately attached to the upper housing 3. Then, the discharge nozzle 6
The upper housing 3 can be assembled by attaching the inflow nozzle 5, the measuring nozzles 7a and 7b, and vacuum-brazing these joints. In the filter 10 of this example, since the element 11 including the connecting pipe 20 is sandwiched and supported by the upper and lower housings 3 and 4, it is not necessary to support the load of the element 11 by the connecting pipe 20 alone. Further, since the lower end 11a and the upper end 11b of the element 11 are supported by hitting the housing 2 directly or via the connecting pipe 20, the element 11 does not resonate and vibrate greatly even when the pressure of air changes. Therefore, a large load is not generated. Therefore, a large load such as the conventional filter that supports the element 11 by the connecting pipe portion alone is not applied to the connecting portion between the connecting pipe 20 and the upper housing 3, and the wall thickness of the connecting pipe 20 is thin. Can be lightweight. For this reason, the load applied to the joint between the connecting pipe 20 and the upper housing 3 is reduced, and sufficient strength can be secured by brazing, which is simple to perform instead of welding. Then, by performing the vacuum brazing, voids that cause defects in the brazing can be removed, so that sound and high-strength brazing can be performed.

As described above, in the filter 10 of this embodiment, the connecting pipe 20 and the filter element 11 which are coaxially connected to each other can be fixed by being sandwiched between the upper housing 3 and the lower housing 4. Therefore, since the connecting pipe 20 has a simple shape such as a cylindrical shape or a rectangular tube shape, the diameter of the cylindrical body portion 23 can be made as large as possible to reduce the pressure loss. Further, since the shape is simple, the connecting pipe 20 can be manufactured by drawing instead of the mold, and since a smooth surface can be obtained, pressure loss due to friction can be suppressed. Further, since the tension bolt is unnecessary, the cross-sectional area of the element interior 12 can be effectively utilized as a fluid path, and also in this respect, pressure loss can be reduced. Therefore, it is possible to provide the filter 10 with less pressure loss from the inflow port to the ejection port.

As described above, the filter 10 of this example
Since the element 11 is vertically sandwiched between the connection pipe 20 and the lower housing 4 joined to the upper housing 3, the element 11 is attached to the connection pipe portion by the conventional filter. Becomes unnecessary. Therefore, when replacing the element 11, it is not necessary to consider the length of the tension bolt, and in the filter 10 of this example, as shown in FIG. 4, the lower housing 4 is not pulled straight downward during maintenance, but is slanted. Or move it laterally to move the upper housing 3
Can be separated from. Therefore, the maintenance space L secured below the filter 10 for element replacement or the like becomes extremely small. Therefore, the installation space of the filter 10 of this example is very small, and the clearance between the filter 10 and the floor, support, or other piping can be greatly reduced. Therefore, the piping system can be designed and constructed compactly.

Further, since the element 11 is fixed so as to be sandwiched between the connecting pipe 20 and the lower housing 4, as described above, the element 1 caused by the pressure fluctuation of the air or the like.
The vibration of No. 1 can be suppressed. In particular, in a filter which accommodates a long element 11 having a large surface area of the filter medium, in which vibration is likely to occur, the effect of suppressing vibration by firmly holding both ends of the element 11 from the housing 2 is large. As described above, in the filter 10 of the present example, the vibration of the element 11 can be suppressed, so that it is possible to prevent the element 11 from being broken and the filter medium from entering the piping system. Therefore, a highly reliable filter with less trouble can be provided. Further, since it is possible to eliminate a member such as a tension bolt that is worn away by repeating attachment and detachment, it is possible to provide the filter 10 that has less trouble during maintenance and exhibits stable performance for a long period of time.

Although the present invention has been described above by taking an air filter installed in an air system for supplying air for process or instrumentation as an example, piping for handling other fluids such as water or oil. Needless to say, the present invention can be applied to a filter installed in the system.

Further, in this example, the annular step portion 31 is formed to join the connecting pipe 20 to the upper housing 3. However, instead of the step portion, another joining structure such as a protrusion or a groove may be adopted. Of course it is possible. Also, the connecting pipe 20
The lower end 22 of the element 11 is inserted into the upper end 11b of the element 11 to connect the element 11 to the connecting pipe 20, but conversely, the upper end 11b of the element 11 may be inserted inside the lower end 22. Of course. Further, in order to set the annular support member 35 joined to the lower end 11a of the element 11 at a predetermined position, the lower housing 4 may be provided with a step, a protrusion or a groove. Further, the support member 35 may be attached to the lower housing 4 side. At this time, as described above, it is desirable that the drain generated in the housing 2 can be discharged from the drain nozzle 41 provided in the lower end wall 4a.

On the other hand, in the filter 10 of this example, the inflow nozzle 5 and the discharge nozzle 6 are provided at positions facing each other .
The filter can be supplied as a general-purpose and easy-to-use filter that does not require a special piping route for connection with the filter 10.

[0030]

As described above, in the filter of the present invention, the filter element coaxially connected to the connecting pipe is fixed so as to be sandwiched between the upper housing and the lower housing. Since the element can be fixed by the upper and lower housings, the tension bolt can be eliminated, and the structure can be simplified and the element can be easily replaced. Furthermore, since the load on the connecting pipe is reduced, a shape with less pressure loss can be adopted, and the pressure loss generated in the filter can be reduced. Therefore, it is possible to provide a filter having a simple structure, a small size, a small pressure loss, and high reliability at low cost. Further, since the tension bolt can be eliminated, maintenance can be facilitated and a filter that requires less installation space can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of an air filter according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing how a lower housing is removed from an upper housing of the air filter shown in FIG. 1 to attach and detach an element.

3 is a cross-sectional view showing how a connecting pipe is attached to an upper housing of the air filter shown in FIG.

FIG. 4 is a cross-sectional view showing how the lower housing is obliquely removed during maintenance of the air filter shown in FIG.

FIG. 5 is a cross-sectional view showing a configuration example of a conventional filter.

[Explanation of symbols]

1, 10 Filter 2 Housing 3 Upper housing 3a Upper end wall 4 Lower housing 4a Lower end wall 5, 6 Connecting nozzle 9 Tension bolt 11 Filter element 12 Element inside 15 Joint of upper and lower housing 20 Connection pipe 21 Connection pipe upper end 22 Connection At the lower end of the pipe, a portion to be inserted into the upper end of the element 23 A cylindrical portion of the connecting pipe 31 A step portion 35 for fitting the upper end of the connecting pipe 35 A support member installed at the lower end of the element

Continuation of the front page (72) Inventor Masuo Yoshioka 246, Kodaka, Suzaka City, Nagano Prefecture Orion Machinery Co., Ltd. (56) References , U) Actual Development Sho 53-85681 (JP, U) Actual Public Sho 37-10374 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) B01D 46/24 B01D 29/11

Claims (5)

(57) [Claims] 1. A filter in which a tubular filter element, which is hollow inside and can be housed substantially coaxially in a tubular housing that can be divided up and down, is connected to the inside of the filter element.
And a fluid discharge or inflow connection connected to this connecting pipe.
An upper joint structure having a connecting nozzle, the upper end wall of the housing being in contact with the upper end of the connecting pipe, and being capable of arranging the connecting pipe substantially coaxially in the housing, a lower end wall, the contact with the lower end of the filter element, the filter element has a lower junction structure can be placed coaxially substantially disposed within the housing, the lower end of the connecting tube, the upper end of the filter element A connecting structure is provided which is in contact with the connecting pipe and the filter element can be connected substantially coaxially , and the connecting nozzle includes an outer peripheral wall of the housing and the connecting wall.
A filter characterized by being attached so as to penetrate an outer peripheral wall of a connecting pipe . 2. The upper joint structure according to claim 1, wherein the upper joint structure is engageable with an upper end of the connecting pipe, and the connecting structure is engageable with an upper end of the filter element,
Further, the lower joint structure is positioned such that the lower end of the filter element hits against the lower joint structure. 3. The filter according to claim 1, wherein the connecting structure has a smaller diameter than other portions of the connecting pipe. 4. The filter according to claim 1, wherein the connecting pipe is made of stainless steel and is drawn. 5. The filter according to claim 4, wherein a lower end of the connecting pipe is a sealing surface that is in contact with an upper end of the filter element.