JP6768437B2 - How to manufacture an oil filter - Google Patents

Description

The present invention relates to a method for manufacturing an oil filter.

Patent Document 1 discloses an oil filter having a bottomed cylindrical case, a filter element housed in the case, and a socket portion having a substantially constant plate thickness for closing the open end of the case. ..

A cylindrical oil outlet is formed in the center of the socket portion of this oil filter. A threaded portion is formed on the inner surface of the oil outlet, which also serves as a mounting portion for the pipe protruding from the receiving seat of the oil filter, and the socket portion is inside the case around the oil outlet. A plurality of oil inflow holes for introducing oil are formed in the.

Japanese Unexamined Patent Publication No. 2003-126612

In such a conventional oil filter, a pressure loss occurs when the oil passes through the oil inflow hole of the socket portion. In order to reduce the pressure loss when passing through the oil inflow hole, it is necessary to increase the hole diameter of the oil inflow hole.

However, the socket portion has a constant plate thickness, and there is a problem that the rigidity decreases as the hole diameter of the oil inflow hole increases, and the withstand voltage strength becomes insufficient.

The present invention includes a bottomed tubular case, an annular filter element housed in the case, and a cover plate formed by press-molding a flat plate having a constant plate thickness to close the open end of the case. The cover plate has a cylindrical tubular portion located at the center and a flange-shaped flange portion located on the outer peripheral side of the tubular portion, and the flange portion has the inside of the case. In the method for manufacturing an oil filter having an oil hole that communicates with each other, the portion where the oil hole is provided is crushed to form a recess larger than the oil hole, and the meat extruded by the formation of the recess is used to surround the recess. It is characterized by having a first step of thickening the wall and a second step of forming the oil hole in the recess.

More specifically, a plurality of the recesses are formed along the circumferential direction of the flange portion, and the wall thickness between the recesses adjacent to each other in the circumferential direction of the flange portion by the first step is the implementation of the first step. It has increased compared to before.

According to the present invention, the flange portion of the cover plate is thickened around the recess when the recess is formed, so that the rigidity is relatively improved. That is, the cover plate is prevented from being lowered in rigidity due to the provision of the oil holes. Therefore, the oil filter can reduce the pressure loss and secure the rigidity of the flange portion of the cover plate at the same time.

Sectional drawing of the oil filter which concerns on this invention. A perspective view of the cover plate as viewed from above. A perspective view of the cover plate as viewed from below. Bottom view of the cover plate. FIG. 4 is a cross-sectional view taken along the line AA of FIG. Explanatory drawing which shows each process of the manufacturing process of a cover plate schematically.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, for convenience, terms such as "up" and "down" are used with reference to the posture of FIG. 1, but the present invention is not limited thereto.

FIG. 1 is a cross-sectional view of the oil filter 1 according to the present invention. The oil filter 1 is used, for example, for filtering oil of an internal combustion engine for a vehicle (for example, lubricating oil, hydraulic oil for hydraulic drive, etc.).

As shown in FIG. 1, the oil filter 1 includes a bottomed cylindrical metal case 2, an annular filter element 3 housed in the case 2, and a metal circular cover that closes the open end of the case 2. It has a plate 4 and a check valve 5.

The filter element 3 is formed by rolling a fold-folded filter paper into an annular shape (cylindrical shape). A first end plate 6 is attached to one end surface of the filter element 3. A second end plate 7 is attached to the other end surface of the filter element 3. The first and second end plates 6 and 7 are made of, for example, thick filter paper.

In the case 2, the first end plate 6 is constantly urged toward the open end side of the case 2 by the spring member 8 arranged in the case 2.

The spring member 8 is a so-called leaf spring, and is formed by, for example, press-molding a flat metal plate. A relief valve 9 is attached to the spring member 8. The relief valve 9 includes a circular dish-shaped valve body 10 capable of opening and closing a through hole 8a formed in the spring member 8, a valve spring 11 that constantly urges the valve body 10 to the spring member 8, a valve body 10 and a valve. It has a valve body 12 for accommodating the spring 11. The valve body 12 is a tubular member in which a part of the body portion is cut out, and is fixed to the spring member 8 by welding or the like.

As shown in FIGS. 1 and 2, the cover plate 4 has a cylindrical tubular portion 13 located at the center and a flange-shaped flange portion 14 located on the outer peripheral side of the tubular portion 13. There is. Here, FIG. 2 is a perspective view of the cover plate 4 as viewed from above in FIG.

The tubular portion 13 of the cover plate 4 also serves as an oil discharge hole for discharging the oil in the oil filter 1 to the outside, and a female screw is formed on the inner circumference.

A plurality of circular oil introduction holes 15 as oil holes are formed in the flange portion 14 of the cover plate 4. The oil introduction hole 15 communicates with the inside of the case 2 and allows oil to flow into the oil filter 1 from the outside.

Further, a metal annular flange plate 16 is previously joined to the cover plate 4 by welding or the like so as to overlap the cover plate 4. The cover plate 4 is fixed to the case 2 via the flange plate 16 by curling the outer peripheral edge of the flange plate 16 and the open end of the case 2. The flange plate 16 is also curled on the inner peripheral side thereof to hold the seal rubber 17.

The seal rubber 17 is in close contact with a portion to which the oil filter 1 is attached (for example, an engine block (not shown)).

On the inner peripheral side of the filter element 3, a metal circular tubular inner cylinder 18 formed so as to penetrate a large number of holes 18a is press-fitted. The inner cylinder 18 is formed, for example, by rolling a steel plate. One end of the inner cylinder 18 is abutted against the first end plate 6, and the other end protrudes from the second end plate 7. Here, the other end of the inner cylinder 18 is a small diameter portion 18b whose diameter is slightly smaller than that of the other portions. A holding portion 18c for the check valve 5 is formed at the tip of the small diameter portion 18b by curling.

The check valve 5 is made of, for example, silicone rubber or the like, has a funnel shape (reverse funnel shape in the posture of FIG. 1), and is attached to the outer periphery of the tubular portion 13 of the cover plate 4. The check valve 5 has a tubular base portion 5a attached to the tubular portion 13 and a tapered valve body portion 5b located on the outer peripheral side of the base portion 5a. The valve body portion 5b is formed so as to cover the oil introduction hole 15 of the cover plate 4 and the outer peripheral edge to be located on the outer peripheral side of the cover plate 4 with respect to the oil introduction hole 15.

The urging force of the spring member 8 acts on the check valve 5 via the holding portion 18c of the first end plate 6 and the inner cylinder 18. As a result, in the check valve 5, the base portion 5a is held by the holding portion 18c of the inner cylinder 18 and the cover plate 4 to seal the inside and outside of the inner cylinder 18, and the outer peripheral edge of the valve body portion 5b is attached to the cover plate 4. Be pressed.

The oil filter 1 is an engine by assembling a female screw formed on the inner circumference of the tubular portion 13 of the cover plate 4 to a male screw formed on the outer periphery of a cylindrical filter mounting portion on the engine block side, which is not shown, for example. Fixed to the block.

In the oil filter 1 configured in this way, when oil flows in from the oil introduction hole 15 at a predetermined pressure, the check valve 5 opens and flows into the case 2. The oil that has flowed into the case 2 flows through the filter element 3 from the outer peripheral side to the inner peripheral side, flows into the inner cylinder 18 through the hole 18a, and flows through the inner peripheral side of the tubular portion 13 to the outside. Flow out. Foreign matter in the oil is trapped as it passes through the filter element 3.

Further, when the oil pressure (pressure loss before and after the filter element 3) becomes high due to clogging of the filter element 3, some oil bypasses the filter element 3 without passing through the filter element 3 and pushes the relief valve 9 open. It flows into the inside of the inner cylinder 18.

Next, the cover plate 4, which is a main part of the present invention, will be described in detail with reference to FIGS. 1 to 5. Note that FIG. 3 is a perspective view of the cover plate 4 as viewed from the lower side in FIG. FIG. 4 is a bottom view of the cover plate 4. FIG. 5 is a cross-sectional view taken along the line AA of FIG.

In the flange portion 14 of the cover plate 4, the inner peripheral portion 14a continuous with the base portion of the tubular portion 13 has a gentle taper shape, and the outer peripheral portion 14b overlapping the flange plate 16 has a flat plate shape. That is, the flange portion 14 has a tapered inner peripheral portion 14a and a flat plate-shaped outer peripheral portion 14b.

Then, as shown in FIGS. 1, 3, and 4, the plate thickness is relative to the inner peripheral portion 14a of the flange portion 14 located between the tubular portion 13 and the outer peripheral portion 14b of the flange portion 14. A plurality of thinned recesses 19 and a plurality of oil introduction holes 15 are formed.

The recesses 19 are formed on the outer surface 20 of the inner peripheral portion 14a of the flange portion 14 at equal intervals along the circumferential direction of the flange portion 14. The oil introduction hole 15 is formed so as to penetrate the recess 19.

In this embodiment, eight recesses 19 and eight oil introduction holes 15 are formed at equal intervals along the circumferential direction of the flange portion 14, but the number of recesses 19 and oil introduction holes 15 is eight. It is not limited. However, the number of recesses 19 and the number of oil introduction holes 15 are the same.

Further, as shown in FIGS. 1 and 5, the wall thickness around the recess 19 is thicker than that of the other portions of the flange portion 14. Therefore, as shown in FIG. 5, the wall thickness between the oil introduction holes 15 and 15 adjacent to each other in the circumferential direction of the flange portion 14 is formed to be thicker than the other portions of the flange portion 14.

As shown in FIG. 6, such a cover plate 4 is formed by press-molding a disk-shaped blank material 21 having a constant plate thickness. In other words, the cover plate 4 is obtained by subjecting the blank material 21 to press molding and plastically deforming it. FIG. 6 is an explanatory view schematically showing the manufacturing process of the cover plate 4 with a perspective view and a cross-sectional view for each process.

In the flange portion forming step, as shown in FIGS. 6A and 6B, the flange portion 14 is formed on the disk-shaped blank material 21 having a constant plate thickness. That is, in the flange portion forming step, a tapered inner peripheral portion 14a and a flat plate-shaped outer peripheral portion 14b are formed on the blank material 21.

In the recess forming step, which is the first step, the recess 19 is formed as shown in FIGS. 6B and 6C. In the recess forming step, the portion of the flange portion 14 where the oil introduction hole 15 is formed is crushed to form the recess 19 larger than the oil introduction hole 15, and the recess is formed by the meat extruded by the formation of the recess 19. The circumference of is thickened. The meat extruded when the recess 19 is formed, and the wall thickness between the recesses 19 and 19 adjacent to each other in the circumferential direction of the flange portion 14 is relatively thickened. That is, the wall thickness between the recesses 19 and 19 adjacent to each other in the circumferential direction of the flange portion 14 is increased by the recess forming step as compared with before the recess forming step is performed.

In the hole forming step, as shown in FIGS. 6C and 6D, the hole is formed so as to penetrate the auxiliary hole 22 for forming the tubular portion 13. The auxiliary hole 22 is formed at a position where the tubular portion 13 is formed so as to have a diameter smaller than the inner diameter of the tubular portion 13.

In the tubular portion forming step, as shown in FIGS. 6 (d) and 6 (e), the tubular portion 13 is formed by drawing while increasing the diameter of the auxiliary hole 22.

Then, in the oil hole forming step, which is the second step, the oil introduction hole 15 is formed so as to penetrate the recess 19 as shown in FIGS. 6 (e) and 6 (f). In this embodiment, after the oil hole forming step is completed, a female screw is machined on the inner circumference of the tubular portion 13.

The oil filter 1 can improve the pressure loss by increasing the size of the oil introduction holes 15 and increasing the number of the oil introduction holes 15.

However, the cover plate 4 has a tubular portion 13 fixed to the attachment partner of the oil filter 1 and an outer peripheral portion 14b of the flange portion 14 which is in close contact with the attachment portion of the oil filter 1 via the seal rubber 17. An oil introduction hole 15 is formed between the two.

Therefore, in the cover plate 4, when the ratio of the oil introduction hole 15 to the inner peripheral portion 14a of the flange portion 14 is increased by increasing the hole diameter of the oil introduction hole 15, the rigidity of the inner peripheral portion 14a becomes relatively large. descend. That is, if an attempt is made to improve the pressure loss of the oil filter 1 by enlarging the oil introduction hole 15, the rigidity of the inner peripheral portion 14a of the flange portion 14 may decrease, which may adversely affect the pressure resistance and the sealing property. ..

Here, in the cover plate 4, the portion where the oil introduction hole 15 is formed is a portion that is finally punched out, and it is not necessary to secure a wall thickness.

Therefore, when the cover plate 4 is press-molded, the portion where the oil introduction hole 15 is formed is crushed before the oil introduction hole 15 is formed, and the recess 19 is formed while forming the recess 19 larger than the oil introduction hole 15. The meat extruded by the formation thickens the circumference of the recess.

As a result, the rigidity of the inner peripheral portion 14a, which is a portion between the tubular portion 13 and the outer peripheral portion 14b, of the cover plate 4 is relatively improved. In other words, the flange portion 14 of the cover plate 4 is thickened around the recess 19 when the recess 19 is formed, so that the rigidity is relatively improved. That is, the cover plate 4 is prevented from being lowered in rigidity due to the provision of the oil introduction hole 15. Therefore, the oil filter 1 can suppress a decrease in rigidity in the portion between the tubular portion 13 and the outer peripheral portion 14b even when the hole diameter of the oil introduction hole 15 is increased. That is, the oil filter 1 can reduce the pressure loss and secure the rigidity of the flange portion 14 of the cover plate 4.

Then, the rigidity of the flange portion 14 having the plurality of oil introduction holes 15 can be relatively improved without increasing the thickness of the flat plate (blank material 21) which is the base material when molding the cover plate 4. It will be possible. That is, in the oil filter 1, it is possible to suppress an increase in the weight of the cover plate 4 while reducing the pressure loss and ensuring the rigidity of the cover plate 4.

Further, since the oil introduction hole 15 is formed in a relatively thin recess 19, it can be easily formed (processed), and the weight of the scrap material produced by punching when the oil introduction hole 15 is formed is relative. It becomes lighter and the yield in press molding can be improved.

1 ... Oil filter 2 ... Case 3 ... Filter element 4 ... Cover plate 5 ... Check valve 6 ... 1st end plate 7 ... 2nd end plate 8 ... Spring member 9 ... Relief valve 14 ... Flange portion 14a ... Inner peripheral portion 14b ... Outer circumference 15 ... Oil introduction hole 16 ... Flange plate 17 ... Seal rubber 18 ... Inner cylinder 19 ... Recess

Claims (2)

A bottomed tubular case, an annular filter element housed in the case, and
It has a cover plate, which is formed by pressing a flat plate having a constant plate thickness and closes the open end of the case.
The cover plate has a cylindrical tubular portion located at the center and a flange-shaped flange portion located on the outer peripheral side of the tubular portion, and the flange portion has an oil hole communicating with the inside of the case. In the method of manufacturing an oil filter having
The first step of crushing the portion where the oil hole is provided to form a recess larger than the oil hole, and thickening the circumference of the recess with the meat extruded by the formation of the recess.
A method for manufacturing an oil filter, which comprises a second step of forming the oil hole in the recess. A plurality of the recesses are formed along the circumferential direction of the flange portion.
The method for manufacturing an oil filter according to claim 1, wherein the wall thickness between the recesses adjacent to each other in the circumferential direction of the flange portion is increased by the first step as compared with that before the first step is carried out. ..

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