JPH01148322A - Filter element and its production - Google Patents

Abstract

PURPOSE:To prevent leakage out of a seal of an upper packing in a filter element consisting of a supporting body, upper and lower supporting ring, filter body, and an upper and lower packing by providing an annular groove and an auxiliary groove along the inside of the annular groove to the upper supporting ring. CONSTITUTION:A filter element 20 is constituted of a filter body 2, a supporting body 21, an upper and a lower sealing packing 22, 23. The filter body 2 comprises a folded filter medium forming a lamp-shade shaped hood, and the supporting body 21 is constituted of a stanchion 24, an upper and a lower supporting ring 26, 25. Further, an annular groove 27 is formed in the upper supporting ring 26, but an auxiliary groove 28 is formed also additionally along the inside of the annular groove 27. A sealing packing 22 is formed by pouring liquid polyurethane foam. The poured liq. polyurethane foam is foamed and solidified annularly on a upper end edge 15a across the annular groove 27 and the filter body 2. An internal peripheral side of the solidified polyurethane reaches the inside of the auxiliary groove 28 due to the expansion in the stage of foam generation. Thus, the fluctuation of expansion due to the foam generation is absorbed by the auxiliary groove 28, and an upper sealing packing 22 contg. no insufficient thickness nor expanded part is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a filter element for an internal combustion engine air cleaner, etc., and a method for manufacturing the same.

(Prior Art) The present applicant proposed a filtering element installed in an air cleaner for an internal combustion engine in Japanese Patent Application No. 19101988. An example is shown in FIG.

The filter element 1 has a striped shape made of radially pleated filter media, and the filter element 2 is placed on the support ll along the conical surface of the support 3, and the annular groove 12 on the upper part of the support and the inner periphery of the filter 2 are connected to each other. An upper seal packing 4 is provided spanning the upper edge 15a of the end surface 15, and a lower seal packing 5 is provided spanning the lower edge 16a of the outer peripheral end surface 16 of the filter body 2 and the lower support ring 13 of the support 3. be. 14 is the top plate of the support. The filter body 2 has pleat lines 17 radially as shown in FIG.
The filter material is made of a filter material that is folded at the valley line 18, and the valley bottom part near the valley line 18 is in close contact with the inner peripheral end face 15, and the peak part near the output line 17 is in close contact with the inside in the vicinity of the outer peripheral end face 16. be. The upper edge 15a of the inner peripheral end surface 15 and the outer peripheral end surface 1
By sealing the lower edge 16a of 6, the inner peripheral end surface 15
Together with the lower surface of the pleats, the outer peripheral end surface 16 forms a flow path on the clean side, for example, and the outer peripheral end surface 16 forms a flow path on the other side, for example, the dusty side, together with the upper surface of the pleats.

To manufacture this filtration element l, the above-mentioned support 3
A cap-shaped filter body 2 is integrally molded with a synthetic resin, and a cap-shaped filter body 2 in which a filter medium is folded radially is placed on the struts 11 of the support body 3, and then a lower lower support ring 13 having an annular groove 30a on the lower surface of the lower support ring 13 is mounted. The mold 30 is brought into contact and the foamable synthetic resin stock solution is poured into the lower mold 30.
and the annular groove 12 of the support body 3, and then the lower upper mold 31 is placed in the lower lower mold 30, and the annular groove 12 and the filter body 2 are injected.
An upper mold 32 is placed over the upper end edge 15a, and the foamable synthetic resin stock solution is foamed and solidified to form the lower seal packing 5 and the upper seal packing 4.

(Problems to be Solved by the Invention) In the above-described filtration element, when molding the upper seal packing, it is necessary to inject an appropriate amount of foamable synthetic resin stock solution into the annular groove of the support, but the composition of the stock solution is Since the foaming state differs depending on the temperature and temperature conditions, it is extremely difficult to control the amount of stock solution injected to form an upper seal packing with an appropriate shape and appropriate apparent density, and the shape is likely to be abnormal.

For this reason, in the conventional filter element, as shown in FIG. 5, a missing part A occurs in the upper seal packing 4 and the upper end edge 15a of the filter body 2 cannot be completely covered, resulting in incomplete sealing, or as shown in FIG. 6. An excessively large bulge B is formed in the upper seal packing 4, and the filtering surface is blocked.

(Means for Solving the Problems) The filtration element of the present invention is provided with an auxiliary groove inside the annular groove of the upper support ring of the support body, and the upper seal packing is arranged between the annular groove and the filtration element like the conventional one. It straddles the upper edge of the body and a part of it is shaped to bulge into the auxiliary area, and the other parts are the same as conventional ones.

In addition, in order to manufacture this filter element, when molding the upper seal packing, an amount of foamed synthetic resin is placed in the annular groove of the upper support ring, spanning the upper edge of the filter body, and in an amount sufficient to bulge into the auxiliary groove. The stock solution is injected, and the foam is solidified so that the expansion caused by foaming reaches the inside of the auxiliary groove. Other steps are the same as the conventional manufacturing method.

(Function) Even if there is some variation in the amount and composition of the stock solution in the upper seal packing or its foaming conditions, the filtration element of the present invention absorbs the variation in the amount of expansion due to foaming by receiving it in the auxiliary groove. If a sufficient amount of stock solution is injected to prevent underfilling after foaming, not only will underfilling of the upper seal packing not occur, but excess will not bulge toward the filter body and reduce the filtration area.

In addition, since slight variations in the amount of stock solution injected into the upper seal packing are allowed during manufacturing, the quality of the stock solution, the amount of injection, foaming conditions, etc. can be easily controlled, and the production of defective products can be reduced.

(Example) FIG. 1 shows a filter element 20 of the present invention.

The filter element 20 consists of a filter body 2, a support body 21, an upper seal packing 22, and a lower seal packing 23. The filter body 2 is the same as the conventional filter body shown in FIG. The support body 21 has an annular groove 27, an upper support ring 26 having an auxiliary groove 28 along the inside thereof, and an annular concave shape 25 that opens downward like a gutter.
The lower support ring 25 has a support ring 25 with a support ring 25, and a strut 24 that connects the two radially. The pillars 24 are connected to the upper support ring 26 at an almost vertical portion 24c of the upper part, arranged radially, and branched into two at the bottom to form a bifurcated pillar 24b, which is connected to the lower support ring 25. The tip of the branch column 24b has a stepped portion 24 in order to improve the molding of the lower seal packing 23.
A is provided. The inside of the auxiliary groove 28 is covered with a top plate 29. The upper seal packing 22 is formed into an annular shape by foaming and solidifying a foamable urethane liquid, spanning the annular groove 27 and the upper edge 15a of the filter body, and the inner circumferential side thereof reaches into the auxiliary groove 28 due to expansion during foaming. . Lower seal packing 23
is formed into an annular shape spanning the lower support ring 25 and the lower edge 16a of the filter body, and is made of foamable urethane.

The method for manufacturing this filter element 20 is as follows. First, the above-mentioned support body 21 is integrally molded with synthetic resin,
A filter body 2 as shown in FIG. 3, which is separately molded and radially pleated, is placed on the pillars 24 of the support body 21. Next, as in the conventional case, the lower lower mold 30 having an annular groove 30a is brought into contact with the lower surface of the lower support ring 25, and the foamable urethane stock solution is injected into the groove 30a and the annular groove 2v of the support body 21. )) Next, a lower upper mold 31 (FIG. 4) and an upper upper mold 33 (FIG. 2 (b)) are placed on each other, and the urethane stock solution is foamed and solidified inside thereof. As shown in FIG. 1(B), the upper mold 33 has an annular shape, covering the annular groove 27, the inner edge 15a of the filter element 2, and the auxiliary groove 28. As shown in FIG. The amount of foamable urethane stock solution injected into the annular groove 27 is such that when it foams and expands, it fills the annular groove 27 and the upper edge 15a of the filter body 2, and a portion bulges into the auxiliary groove 28. The annular groove 27 is adjusted to
injected into.

(Effect of the invention) Since this invention has the above configuration, the filtration element is
The desired filtration function is ensured without causing seal leakage due to lack of thickness in the upper packing, or excessive swelling on the upper end surface of the filter body and blocking the filtering surface.

Further, in this filter element, the variation in the amount of expansion due to foaming during molding of the upper seal packing is absorbed by the auxiliary groove, so the injection mold can be easily adjusted, and malfunctions or unsightly defective products can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a filter element according to an embodiment of the present invention;
FIGS. 2(A) and 2(B) are views showing the formation of the upper seal packing. FIG. 3 is a perspective view of a filter body, and FIG. 4 is a diagram showing a conventional filter element and molds for forming its upper and lower seal packings. FIGS. 5 and 6 are diagrams showing malfunctions of conventional upper seal packings. 2...Filter body 21...Support body 2
2... Upper seal packing 23... Lower seal packing 24...
・・Strut 25・・Lower support wheel 26・・・・
・・Lower support ring 27・・・・Annular groove 28・・
...Auxiliary groove 30...Lower lower mold 31...
...Lower upper mold 33... Upper upper mold

Claims (2)

[Claims] (1) A support having an upper support ring, a lower support ring, and a plurality of supports connecting them along a conical surface, a cap-shaped pleated filter placed on the supports of the support, and A filtration element consisting of an annular upper seal packing extending from the upper support ring to the upper edge of the filter body and an annular lower seal packing extending from the lower support ring to the lower edge of the filter body, the upper support ring having an annular groove and an annular groove. Filtration element with auxiliary grooves along the inside. (2) A support body comprising an upper support ring having an annular groove and an auxiliary groove along the inside thereof, a lower support ring provided below and outward from the ring, and a plurality of supports connecting these and extending along a conical surface. A cap-shaped filter body is placed on the support column, a lower lower mold having an annular groove is brought into contact with the lower surface of the lower support ring, and the stock solution of the foamable synthetic resin material is poured into the annular groove of the upper support ring and the lower part. The foamed synthetic resin material is injected into the groove of the lower mold, and then the annular groove, the auxiliary groove, the upper lid mold that covers the upper edge of the filter body, and the lower lid mold that covers the upper surface of the lower support ring are respectively covered. A method for manufacturing a filtration element in which the stock solution is foamed and the upper seal packing is solidified so that the swelling caused by the foaming of the stock solution reaches the auxiliary grooves.