JPS602894B2 - Strainer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a strainer for filtering and removing dust, scale, etc. contained in a fluid.

Conventionally, there is a strainer using a single cylindrical filter as shown in FIG.

In Figure 3, the strainer crab body is a cylindrical body 1 with a bottom.
, is formed from a lid 2 that closes the upper entrance of the main body 1. bulge 1,
2 is provided with an inlet 5, an outlet 6, and a filtration passage 3 passing through both ends. A filter 4 formed by winding a porous metal plate into a cylindrical shape is arranged inside the filtration pilgrimage 3. An annular flange 7 is provided on the outer periphery of the upper end of the filter 4, and is engaged with a partition wall 8 on the inner wall of the main body 1. The lower end of this filter 4 is fitted with a bottom plate 10, and this plate 10 is supported via bolts and nuts 11 on a beam 9 extending over the upper end. The beam 9 is provided so as not to obstruct the passage of fluid, and on top of the beam 9 is attached a material 12 which also serves as a stop for the filter 4 to rise and a handle when lifting the filter 4. The area of the filter is M = where M is the area, x is the fluid passage rate, 1 is the cross-sectional area of the inlet, and S is the safety factor.
Determined based on the formula of support XS.

The cross-sectional area and length of the filter 4 are designed to ensure the required area M. The cross-sectional area of filter 4 is inlet 5
It is necessary to make the cross-sectional neck of
Make it larger. For this reason, the filter 4 is generally shortened by increasing its cross-sectional area, and the main body 1 is made smaller. In this case, there are the following problems. The filter 4 is single-layered, and requires a large cross-sectional neck to ensure the required filtration area.
If the cross-sectional area of the filter 4 is increased, the lid 2 will have a larger diameter, which will require a thicker wall for strength and a larger number of bolts and nuts to be fastened to the main body 1. Due to the above reasons, the strainer bulge is large and the cost is high. FIG. 4 shows another conventional example, and parts common to those in FIG. 3 are given the same reference numerals and their explanation will be omitted.

In FIG. 4, a cylindrical inner filter 13 having a smaller cross-sectional area and shorter length than this filter is disposed inside the filter 4. This filter 13 has bolts and nuts 14
The upper part is fixed to the beam 9 with the annular flange 15, and the lower part is fixed to the filter 4 with the annular flange 15. In the strainer of the above structure, taking into account that the cross-sectional mirror of the filter 4 is large, the filter area in which the inner filter 13 is arranged within the filter 4 is secured by a 4-shaped filter.

Moreover, by this, the main body 1 and the lid 2 are made smaller, and the strainer body is made smaller, thereby obtaining a low-cost strainer. However, the strainer with this structure has the following problems. There is an unused space C between the filter 4 and the lid 2. Since this space is not utilized, there is a limit to the miniaturization of the filter, the cross-sectional area is still large, the lid 2 has a large diameter and a large number of bolts and nuts are required, and the strainer bell body is large and costly. An object of the present invention is to improve the above-mentioned conventional strainer, make effective use of the space within the strainer, and reduce the size of the mackerel body while ensuring the required filter area, thereby obtaining an economical strainer. The technical means of the present invention taken to achieve the above object is as follows. Place the inlet end of the outer filter in contact with the inner wall of the crab body so that it passes outward.'

} A cone-shaped inner filter is placed inside the outer filter, the large diameter end of the inner filter is connected to the outlet end of the outer filter, and the small diameter end of the inner filter is connected to the exit end of the outer filter through the inlet end of the outer filter. It is also placed so as to protrude toward the entrance.

The operation of the above technical means is as follows.

That is, the fluid at the inlet passes through the outer filter from the inside to the outside, passes through the inner filter from the outside to the inside, and flows out to the outlet. At this time, the outer filter has a cylindrical shape and the inner filter has a cone shape that gradually becomes thinner from the outlet side to the inlet side, so the space between the inner and outer filters is wider towards the inlet and narrower towards the outlet. The cross-sectional area of the inner filter is narrower on the inlet side and wider on the outlet side, so the cross-sectional area of the fluid before filtration is larger at the inlet side of the filter, and the cross-sectional area of the fluid after filtration is larger at the outlet side of the filter. The proportion increases.
Therefore, the fluid at the inlet reaches the filter surface without being hindered, and a large amount of fluid that has passed through the large area inner filter protruding toward the inlet can also flow out toward the outlet without being hindered. Therefore, by making the inner filter into a cone shape and protruding toward the inlet side, the required filtration area can be secured without increasing the diameter of the outer filter and even if the outer filter is shortened, and the strainer housing can be made smaller accordingly. It can be done. Next, the present invention will be explained based on the embodiment shown in FIG.

The main body 21 has an inlet 22 and an outlet 23 that are coaxially connected horizontally, a filtration passage that communicates the two ports 22 and 23, and a partition wall 24 that partitions the inlet 22 and the outlet 23. Main body 21
The upper opening is closed with a lid 26 attached via bolts and nuts 25. The main body 21 and the lid 26 form a strainer body. 27 is a gasket.

A lifting handle 28 is screwed into the center of the lid 26. The filter 29 is made of a cylindrical outer filter 30 and a cone-shaped inner filter 31. The filters 30 and 31 are made by winding a porous metal plate into a cylindrical or cone shape, and sintering silk finer than the filter holes inside the metal plate. filter 3
An annular flange 32 is welded to the outer periphery of the upper end of 0, and this flange 32 is engaged with a shoulder 33 of the partition wall 24.

Further, an annular flange 34 is welded to the inner periphery of the lower end of the filter 30, and the inner periphery of this flange 34 is welded to the lower total outer periphery of the filter 31. The filter 31 is longer than the filter 30, and its upper end meets the annular wall 36 of the lid 26. Further, the upper end of the filter 31 is closed with an upper plate 35.
A member 37 is attached to the upper surface of the upper plate 35, which serves as a handle for lifting the filter and also to prevent the filter from rising. This city material 3
7 is made of an elastic body such as a spring. A through hole is provided in the lower part of the main body 21, and a drain plug 38 is screwed into the through hole to close it. The operation of the above embodiment will be explained.

The fluid flowing in from the inlet 22 is passed through the inner and outer filters 30 and 31.
through the outlet 23. Impurities such as dust and scale contained in the fluid are filtered out by filters 30 and 31. The inner filter 31 is longer than the outer filter 30 and largely protrudes into the passage on the inlet side. A portion of the fluid is filtered by the protruding portion, and the amount of fluid flowing through the non-protruding portions of the outer filter 30 and the inner filter 31 is reduced. Therefore, the excess area required in this portion is small, and the outer filter 30 can have a small cross-sectional area and a small diameter. Inner filter 31
is cone-shaped and expands downward, and the filtration area becomes larger compared to a case where, for example, a cylindrical filter with the same upper end portion of the outer filter 30 is used. Therefore, since the filters 30 and 31 have expanded the filtration area by making use of the space that was not used in the past, it is possible to use a small filter, and the strainer housing can be made small, especially the lid 2.
6 has a small diameter so that the number of bolts and nuts 25 can be reduced and thin ones can be used, and a low-cost strainer can be provided. The filters 30, 31 are welded together via a flange 34 so that they can be installed and removed as one piece, and the joint is complete and does not filter or leak fluid. This filter 3
Since the weights 0 and 31 are each supported by the inner wall of the weight body and pressed by the support material 37, they do not move during use and are stable. Next, an embodiment of the present invention shown in FIG. 2 will be described.

This embodiment is of a type called a Y-type strainer. The body 51 forms a filtration passage through an inlet 52, an outlet 53, and both ports. This main body 51 has an opening □ at the bottom, and a lid 55 is bolted to this closed opening via a gasket 54.
Attach with an attachment means (not shown) such as a nut. Main body 5
1 and the lid 55 form a strainer body. One end of the cylindrical outer filter 56 is attached to the inner wall of the body via a flange 57. The other end of the filter 56 is connected to a cone-shaped inner filter 59 via a flange 58 . The inner filter 59 is longer than the outer filter 56, and its other end extends beyond the filter 56 onto the filtration passage. This end secures the top plate 60. The inner wall of the lid 55 is a filter 56.5
A plurality of protrusions 61 are provided to hold the ends of the protrusions 9. The filters 56 and 59 of this embodiment are the filter 3 of the embodiment of FIG.
It has the same effect as 0.31 and can be made smaller, and the strainer body is correspondingly smaller and can be manufactured economically. In the present invention, the cone-shaped inner filter is longer than the cylindrical outer filter, and the inner filter has a structure that extends beyond the outer filter and protrudes into the filtration passage.

With this structure, the space within the strainer body, which has not been used in the past, can be effectively utilized. A part of the fluid is filtered by the part of the inner filter that protrudes outside the outer filter, and the amount of fluid to be filtered by the non-protruding parts of the outer filter and the inner filter is reduced, and the cross-sectional area of the outer filter can be reduced.
As a result, the lid has a small diameter, and the number of bolts and nuts for attachment can be reduced and small ones can be used. Further, the inner filter is cone-shaped, and the filtration area is increased by the enlarged diameter of the portion corresponding to the end of the outer filter compared to a cylindrical filter having the same cross-sectional area. Therefore,
A small filter with a small cross-sectional area is used, and the strainer crab body can be made small, so an economical strainer can be provided.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a strainer according to an embodiment of the present invention;
The figure is a sectional view of a strainer according to another embodiment, and FIGS. 3 and 4 are sectional views of conventional strainers. 21,51... Main body, 22,52...
Inlet, 23,53... Outlet, 26,55... Lid, 30,
56...outer filter, 31, 59...inner filter,
32, 57...Flange. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. Place a cylindrical outer filter in the filtration passage connecting the inlet and outlet in the strainer housing, and insert the inlet end of the outer filter into the housing so that the fluid at the inlet passes from the inside of the outer filter to the outside. A cone-shaped inner filter is arranged in contact with the inner wall, and the large diameter end of the inner filter is connected to the outlet side end of the outer filter, and the small diameter end of the inner filter is connected to the inlet side opening of the outer filter. A strainer that extends through the opening end and projects toward the inlet side.