JPS5912323B2 - fluid filter - Google Patents

Description

[Detailed description of the invention] The present invention relates to integrally molded fluid filters.

More particularly, the present invention relates to injection molded in-line fluid filters of relatively small size.

In-line fluid filters are used to filter various types of fluids, such as filtering liquids flowing through a system.

In the conventional apparatus, a flat nylon mesh is rolled into a cylindrical shape and placed in a mold, and reinforcing means and end attachment members are molded into the nylon mesh using plastic insert molding.

However, nylon mesh is very brittle and difficult to handle.

Also, post-forming operations are relatively expensive and pose many problems.

Furthermore, the fine mesh for filters is small and has a complex shape, which poses problems in molding.

This means that many of the sections of the mold are too small to fill with resin, creating voids in the filter and resulting in rejects, resulting in a high volume of rejects.

Moreover, making the molds for molding requires a lot of time and money because the workmanship is so detailed.

Another problem with conventional filters is that because the filters are made from a flat screen, small particles tend to clog the mesh.

Additionally, conventional filters cause turbulence, which increases filtration resistance.

Therefore, it is an object of the present invention to provide a filter manufactured by injection molding without using nylon mesh.

Another object of the present invention is to provide a fluid filter that allows microscopic substances to accumulate without clogging the pores of the filter.

Another object of the present invention is to provide a fluid filter with reduced turbulence and low filtration resistance through which fluid flows in laminar flow.

To achieve these objects, the present invention has a base having a fluid passage therethrough, a head axially spaced apart from the base by a predetermined distance, and axially disposed between the base and the head. a plurality of annular rings spaced apart and each having a predetermined inner diameter and outer diameter; at least one reinforcing rib provided in the axial direction between the base and the head; and a circular ring between the base and the head. a plurality of ribs provided in the axial direction and spaced apart in the circumferential direction, the plurality of ribs have outer surfaces joined to the respective inner peripheries of the plurality of rings, and protrude radially inward from the joint surfaces; Each of the ribs and each of the annular rings cooperate to form a plurality of filtration openings of a predetermined size in the same plane as the joint surface, and each of the plurality of rings has a uniform cross section; , the plurality of ribs are spaced apart from each other in the axial direction by X degrees uniformly, and the plurality of ribs have side surfaces that converge inward to give the filter opening a uniform size; protrudes radially outward from the joint surface between the ring and the rib, has a wall thickness in the circumferential direction larger than the plurality of ribs, and integrally connects the plurality of rings spaced apart in the axial direction. In particular, the reinforcing ribs not only have a reinforcing effect to connect multiple rings separated in the axial direction and make the filter more robust, but also act as conduits for flowing resin when injection molding the filter.
It also helps to completely form the rings.

The present invention will now be described with reference to the accompanying drawings.

In Figures 1-4, 10 indicates a fluid filter according to the invention.

This filter 10 has a large number of small ω-shaped rings 12.

Each ring 12 has the same cross-sectional shape and is equally spaced apart along the longitudinal direction of the filter (vertical direction in the drawing).

A large intermediate ring 14 is located in the longitudinally intermediate portion.

The outer diameter of this intermediate ring 14 is smaller than the inner diameter of the housing tube 36 that houses the filter 10.

On both sides of the filter, there are thick reinforcing ribs 16 along the longitudinal direction.
18, this rib cooperates with the intermediate ring 14 to reinforce the filter, and also allows the resin to flow smoothly within the mold during molding to form a uniform filter, as will be described later.

The filter 10 has a head 20 whose upper end is closed, and in this embodiment, ears 21, 22, 23 radially extend from the head 20.
．． 24 is overhanging.

The ears hook onto the upper end of the housing tube 36 to suspend the filter concentrically within the housing tube.

However, this ear portion is not absolutely necessary and may be omitted.

Further, a tab 26 projects upward from the head, and this tab is provided with a plurality of notches 27 (FIG. 2).

This tab can be used to hold the filter when attaching and detaching it with pliers, and the notch is used to prevent it from slipping.

A base 28 having a hollow fluid passageway at the lower end of the filter.
The outer diameter of the base 28 fits snugly into the inner diameter of the receiving tube.

There is a recess 29 on the outer periphery of the base 28, in which the O-ring 2 is inserted.
Accept 9a.

Reference numeral 30 denotes a vertical rib whose upper end is joined to the base at the lower end of the head, and these ribs 30 are provided in large number at intervals in the circumferential direction, and are integrally joined to the inner surfaces of the rings 12 and the intermediate ring 14. are doing.

The inner surface of each rib 30 is vertical over its entire length, but the outer surface is an inclined surface with an upwardly decreasing thickness. The closer it is, the smaller it is.

The rings 12... and the ribs 30... cooperate to form a rectangular opening 34 suitable for offshore applications (FIG. 7).

The cross-sectional shape of each rib 30 is a truncated triangle with each side 30a and 30b sloped so as to converge toward the center of the filter.

Due to the inclination of the outer surface of the ribs and the change in diameter of the ring 12, which has a uniform cross-sectional shape, the diameter becomes smaller as it approaches the head 20, the entire opening 34 formed by the intersection of each ring 12 and each rib 30 is The size will be essentially the same.

In order to use this filter, it must be inserted into the fluid conveyance path of various equipment.
6 is inserted.

The conduit has a flared, flared end 38 at its upper end, so that it can be secured to another conduit or to a connecting member in cooperation with a threaded connecting nut 40.

The enlarged diameter end portion 38 receives the ears 21-24 and supports the filter.

In the illustrated example, the direction of fluid flow is from head 20 to base 2.
It is supposed to be 8.

Fluid enters the interior of the filter through opening 34.

In this case, the inner ribs 30 tend to convert the turbulent flow of fluid into laminar flow behind the openings 34.

As is clear from FIG. 7, particles 44 in the fluid are caught on the upper and lower parts of the IJ ring 12 and are prevented from entering the inside of the filter.

Each ring is located outside the outer surface of the rib 30, i.e., projects outside the aperture, so that fluid passing near the particle 44 passes around the particle in the direction of the arrow and passes through the aperture hidden by the particle. 34a allows entry into the filter.

Therefore, the possibility that the opening 34 becomes clogged with particles in the fluid is minimized.

Figures 5 and 6 show the mold and core for manufacturing the above-described filter.

The mold 50 consists of a first mold 52 having a mold mating surface 54 and a second mold 53 having a mold mating surface 56 .

The mold mating surfaces 54 and 56 do not become airtight even when mated, and a gas vent is formed in the joint metal body to allow air or gas to escape.

Semi-circular molding recesses 58, 59 of both molds traverse this seam, thereby promoting ventilation of each recess and preventing the recesses from being filled with plastic material during the forming operation. Assure.

The molding recesses 58, 59 are substantially equidistantly spaced along the longitudinal axis of both molds 52, 53, so as to form the ring 12 described above.

The semicircular recesses 58, 59 define an annular recess of substantially uniform cross-sectional area along the length of the mold.

A large recess 60 is formed in mold 52 and is aligned with a similarly shaped large recess in mold 53.

A respective longitudinal channel 62,63 is formed in the mold 52,53 over its entire length.

The cavity part 64 forms the head of the mold and the recess 6
It includes a hemispherical end wall 66 leading to 7.

Recess 67 forms part of longitudinal channel 62 .

Cavity 64 includes ear forming recesses 68 and 69 located in the plane of mating surface 54 and ear forming recess 70 located at the rear of head cavity portion 64 .

A similarly shaped selvedge recess is formed behind the head of the mold 53.

These ear forming recesses create the ears 21.22.23.24 of the filter 10 of FIGS.

However, this ear-forming recess may be omitted.

A base forming recess 72 is formed in the bottom end of mold 52.

A reduced diameter section 73 extends into the enlarged diameter section 74 and forms an annular recess 29 of the filter 10 .

Preferably, the base-forming recess 72 and the annular recess 74 are of substantially the same diameter to provide a snug fit within the receiving tube 36.

76 indicates a core placed between 52 and 53.

Core 76 has an end plate 75 to seal the lower end of the cavity.

The core has a number of radially outwardly extending and axially extending splines 77 around it.

The diameter of the central portion 78 of the core 76 is substantially uniform over the length of the core.

However, the radially outward end surface of each spline 77 is tapered along the longitudinal direction, as shown in FIG.

The lands between the molding recesses 58 of each mold are uniformly tapered so that the diameter decreases from the bottom to the top of the mold.

Since these lands have substantially the same diameter as the distal end surface of spline 77, they contact each other.

Further, the end surface of the spline has an arc shape that matches the circular land surface.

A rectangular opening 34 is formed where the end surface of the spline 77 and the land between each molded recess 58 intersect and contact.

Each spline 77 has side surfaces parallel to each other, so that the rib 30 has convergent side surfaces 30a and 3.
Form 0b.

80 is a gate through which resin enters during injection molding, and is formed in the mold 52.

During the molding operation, the resin passes through the gate 80 into the large annular recess 6.
0 and flows along the longitudinal path 62 of the mold 52 and around the annular path 60.

It also flows into the longitudinal channel 63 of the mold 53 and towards the head and base of the cavity.

The resin also passes from the longitudinal path 62.63 through the semicircular recess 58.59 to the molding surface 54.56.

As the resin is thus forced into the gap in the cavity, the air in the cavity is forced out through the small gap between the mating surfaces 54, 56.

Therefore, although the cavity for molding the filter of the present invention is complex, it is possible to completely fill the resin with no air gaps and manufacture the filter.

Although the present invention has been described above with reference to specific embodiments, the present invention is not limited to the illustrated embodiments.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and Fig. 1 is an elevational view of a state in use housed in a storage tube shown in cross section, and Fig. 2 is a view taken out of the storage tube and rotated 90 degrees. 3 is an enlarged sectional view taken along line 3-3 in FIG. 2, FIG. 4 is a sectional view taken along line 4-4 in FIG. 3, and FIG. 5 shows one side of the mold for molding the filter. FIG. 6 is a sectional view taken along the line 6--6 in FIG. 5, and FIG. 1 is a partially enlarged perspective view showing r overaction. In the figure, 12 is a ring, 16 and 18 are reinforcing ribs, 20 is a head, 28 is a base, 30 is a rib, and 30a. 30b is a side surface of the rib, and 34 is a filtration opening.

Claims (1)

[Scope of Claims] 1. A base portion having a fluid passage passing through it in the axial direction, a head portion axially separated from the base portion by a predetermined distance, and a portion provided between the base portion and the head portion separated from each other in the axial direction. , a plurality of annular rings each having a predetermined inner diameter and outer diameter, at least one reinforcing rib provided in the axial direction between the base and the head, and spaced apart in the circumferential direction between the base and the head. a plurality of ribs provided in the axial direction, each of the plurality of ribs having an outer surface joined to each inner periphery of the plurality of rings and protruding radially inward from the joint surface; , each of the annular rings cooperates to form a plurality of filtration openings of a predetermined size in the same plane as the joint surface, and the plurality of rings have uniform cross-sections and are mutually spaced from each other. The plurality of ribs are uniformly spaced apart in the axial direction, and the plurality of ribs have side surfaces that converge inward to give the filtering opening a uniform size; protrudes radially outward from the joint surface with the ribs, has a wall thickness in the circumferential direction greater than the plurality of ribs, and integrally connects the plurality of rings spaced apart in the axial direction. and fluid filters.