WO2001068217A1

WO2001068217A1 - Oil filter

Info

Publication number: WO2001068217A1
Application number: PCT/KR2000/000700
Authority: WO
Inventors: Chong-Kwan Park
Original assignee: Good Luck Industry Co., Ltd.
Priority date: 2000-03-15
Filing date: 2000-06-30
Publication date: 2001-09-20
Also published as: JP2003526500A; KR200196681Y1; AU5577300A

Abstract

An oil filter is provided. The oil filter including a cap housing having a cap stiffener where an inlet and an outlet are formed, an element which is installed inside the cap housing for filtering oil flowing in through the inlet and exhausting the filtered oil through the outlet, a check valve installed between the cap stiffener and the element for preventing a reverse flow of oil out through the inlet, and a spring which is installed inside the cap housing for allowing the element to closely contact the cap stiffener. The element is formed of metal and includes upper and lower caps, and a filter net installed between the upper cap and the lower cap. The filter net is formed by weaving relatively thick metal wires and relatively thin metal wires together.

Description

OIL FILTER

Technical Field

The present invention relates to an oil filter for removing foreign materials from oil in a combustion engine.

Background Art

Referring to FIG. 1 , a conventional oil filter includes a cap housing 10 made of metal, an element 20 installed inside the cap housing 10, a spring 30 installed between the cap housing 10 and the element 20, and a check valve

40 made of a rubber or rubber-like material for preventing a reverse flow of oil out through a filter inlet.

The cap housing 10 consists of cap stiffener 11 , a case 12, and a cap seaming portion 13 for seaming the cap stiffener to the case 12. In the cap stiffener 11 , an inlet 14 and an outlet 15 are formed. The inlet 14 through which oil flows in is disposed outside the element 20, and the outlet 15 through which the oil is exhausted is disposed inside the element 20.

The element 20 includes a metal upper cap 21 , a lower cap 22, a support plate 23, and a filter 24 made of pulp or non-woven fabric. The element 20 is elastically biased by the spring 30 to closely contact the cap stiffener 11. The support plate 23 supports the upper cap 21 and the lower.* cap 22, thereby sustaining the shape of the filter 24. The filter 24 has a shape like an accordion having many folders to increase the area for passing oil. Both ends of the filter 24 adhere to the upper and lower caps 21 and 22 by epoxy resin 26.

In the oil filter having the above structure, when oil under a predetermined hydraulic pressure flows in through the inlet 14, the oil is filtered while passing the filter 24 made of pulp or non-woven fabric, exhausted through the outlet 15, and then flows into an engine. However, the conventional oil filter having the above structure has disadvantages.

First, since the amount of filtered oil is proportional to the area of a filter made of pulp or non-woven fabric, and as the capacity of an engine increases, the size of the filter increases, and thus an oil filter is larger.

Second, when a car travels suddenly at high speed, the pressure of an oil pump rapidly rises, and thus oil flows in under a high pressure. Then, the filter can be damaged due to the oil pressure such that portions folded like an accordion in the filter are stuck to each other or crumpled, or filter pores become wider. Therefore, unfiltered oil flows into the element 20 and then is exhausted through the outlet15. Thus, foreign materials included in the oil directly enter the engine, and the life span of the engine may be reduced and the gas mileage rating may deteriorate.

Third, a filter is thick, and the diameter of a filter pore is irregular, varying between 25 μ and 250 μm along a substantially long path through a pore. Accordingly, the long path of the filter pore can easily be clogged by foreign materials. Even if oil passes through the filter, some foreign materials may not be filtered and may be included in the oil since the diameter of the filter pores is irregular.

Fourth, since the filter made of pulp or non-woven fabric is always soaked in pollutants, including oil and foreign materials, the filter cannot be recycled. When an oil filter is discarded, the filter soaked in pollutants must be separated. However, it is nearly impossible to separate a seamed cap stiffener from a case,, so the oil filter must be buried. Accordingly, a. problem of polluting soil is caused.

Fifth, the filter should be processed, by. folding many times like an accordion, to enlarge the filtering area, and a large amount of epoxy resin must be used to adhere the folded filter to the upper and lower caps. Also, an adhering process is required. In other words, epoxy resin is applied to the contact area of the filter, and the filter is adhered to the upper and lower caps and baked at a temperature of 130-150° C for 120 seconds, so that the manufacturing process is complicated and the time required for manufacturing the product is long, thereby inhibiting mass production.

Sixth, a large amount of poisonous material such as dioxin is produced when manufacturing filters made of pulp or non-woven fabric. Disclosure of the Invention

To solve the above problems, it is an objective of the present invention to provide an oil filter which can maintain filtering capability when a car travels at high speed or when the oil filter is used for a long time, can be easily recycled, does not pollute the environment, and can be mass produced.

Accordingly, to achieve the above objective, there is provided an oil filter including a cap housing having a cap stiffener where an inlet and an outlet are formed, an element which is installed inside the cap housing for filtering oil flowing in through the inlet and exhausting the filtered oil through the outlet, a check valve installed between the cap stiffener and the element for preventing a reverse flow of oil out through the inlet, and a spring which is installed inside the cap housing for allowing the element to closely contact the cap stiffener. The element includes upper and lower caps and formed of metal, and a filter net installed between the upper cap and the lower cap. The filter net is formed by weaving relatively thick metal wires and relatively thin metal wires together.

The oil filter also includes a safety valve including an inner cap, which protrudes from the lower cap toward the inside of the element and is provided with a through hole, a valve plate, which is installed at about the center of the inner cap to close or open a through hole of the lower cap, and a safety valve spring, which is installed between the inner cap and the valve plate.

The diameter of the thick wire of the filter net is 0.2-0.4 mm, and that of the thin wire is 0.1-0.3 mm The diameter of a filter pore formed by .the thick wire and the thin wire is 25-80 μm. Preferably, the check valve is made of metal.

Brief Description of the Drawings

The above objective and advantages of the present invention will become more apparent by describing in detail a preferred embodiment thereof with reference to the attached drawings in which:

FIG. 1 is a semi-sectional view of a conventional oil filter;

FIG. 2 is a semi-sectional view of an oil filter according to the present invention; and

FIG. 3 is a partial, exploded perspective view of the element of FIG. 2.

Best mode for carrying out the Invention Referring to FIG. 2, an oil filter according to the present invention includes a cap housing 110 made of metal, an element 120 made of metal and installed inside the cap housing 110, and a check valve 140 for preventing a reverse flow of oil out through an inlet. Here, a spring 130 is installed in the cap housing 110 so that the element 120 closely contacts a cap stiffener 111 which will be described below.

The cap housing 1 10 is comprised of the cap stiffener 111 , a case 1 12, and a cap seaming portion 113 for seaming the cap stiffener 111 to the case 112. In the cap stiffener 111 , an inlet 114 and an outlet 115 are formed. The inlet 114 through which oil flows in is disposed outside of the element 120, and the outlet 115 through which oil is exhausted is disposed inside the element 120. The outlet 115 is formed at the center of the cap stiffener 111 and the inlet 114 is formed around the outlet 115 being separated a predetermined distance therefrom.

The element 120 is elastically biased by the spring 130 to closely contact the cap stiffener 111. The element 120 consists of upper and lower caps. 21 and 122 made of metal, a filter net 123 made of metal and installed between the upper and lower caps 121 and 1.22, and a. safety valve 125 which is opened to let oil.fiow when the oil is at a predetermined pressure, or higher.. As shown in FIG. 3, a hole 121 a corresponding to the outlet 115 is formed at the center of the upper cap 121. Accordingly, the inlet 114 of the cap stiffener 111 is disposed outside the filtering element 120, and the outlet 115 is disposed corresponding to the hole 121 a of the upper cap 121.

The filter net 123 entirely formed of metal is strictly seamed to the upper cap 121 and the lower cap 122. As shown in FIG. 3, this seaming is effected by clinching together the coupling grooves 122a of the upper and tower caps 121 and 133 using a press after inserting the filter net 123 into the coupling grooves 122a. Accordingly, epoxy resin and an adhering process, which are used to fix the filter in conventional technology, are not required, thereby facilitating mass production.

The filter net 123 is formed by weaving relatively thick wires 123a arrayed at equal intervals, and relatively thin wires 123b into a mesh. The diameter of each thick wire 123a is 0.2-0.4 mm and that of each thin wire 123b is 0.1-0.3 mm. In this embodiment, the diameters of each thick wire 123a and each thin wire 123b are 0.36 mm and 0.25 mm, respectively. The diameter of each of the filter pores, through which the oil passes, and which are formed by the thick wires 123a and the thin wires 123b, is about 25-80 μm, and, in this embodiment, is 65μm. The filter pores are densely and uniformly formed compared to conventional technology in which the diameter of a pore in a filter made of pulp or non-woven fabric is irregular at about 25-250 μm. It is preferable that the filter net 123 is made of chemically stable stainless steel or steel. Since the filter net 123 is formed of metal exhibiting great pressure- withstanding capability, even when a car suddenly travels at high speed and a large amount of oil under a great pressure flows in the filter, the oil can be filtered without damaging the filter net 123. Accordingly, a large amount of oil can be filtered, thereby fundamentally preventing foreign materials from flowing in an engine.

In addition, since the filter net 123 has a great pressure-withstanding capability compared to that of a conventional filter, an oil filtering ate per area is very great. Consequently, an engine capacity which the filter net .123 can cover becomes great so that the filter of the present invention can be applied to engines of various capacities.

The thickness of the filter net 123 is 1 mm or less. Compared to a conventional filter formed of pulp or non-woven fabric (usually having a thickness of 2 mm or more), the filter net 123 is thinner and has uniform filter pores. Accordingly, a path through a filter pore is substantially short, and thus the filter pore is not clogged by foreign materials.

Meanwhile, the filter pores in the filter net 123 are dense and uniform, thereby filtering foreign materials which are not filtered by a conventional filter. Since the filter net 123 is formed of metal, the entire filter can be formed of metal. Accordingly, it is not necessary to separate the filter net 123 when the filter is discarded, and the filter can be readily recycled without polluting the environment. In addition, since the filter net 123 has a great pressure-withstanding capability, it substantially has a great filtering ability. Accordingly, it is not necessary to fold a filter many times like an accordion in order to increase the filtering area, nor to use epoxy resin and an adhering process to adhere the filter net to the upper cap and the lower cap. Therefore, the present invention facilitates mass production and reduces manufacturing time and cost.

The safety valve 125 includes an inner cap 125a, which protrudes from the lower cap 122 toward the inside of the element 120 and is provided with a through hole 125d, a valve plate 125b, which is installed at about the center of the inner cap 125a to close or open a through hole 122d of the lower cap 122, and a safety valve spring 125c, which is installed between the inner cap 125a and the valve plate 125c. In the case where the safety valve 125 is employed for an engine of large capacity, when oil at high pressure suddenly flows in, the valve plate 125b is pushed by the hydraulic pressure of the oil, and thus the oil can immediately flow into the element 120. Consequently, sufficient oil can flow in the engine.

The check valve 140 is installed between the cap stiffener 111 and the upper cap 121 to prevent the reverse flow of oil. The check valve.140 is formed to be. complementary to an inner surface of the cap stiffener 111 so that, when oil flows back to the inlet 114, the check valve 140 contacts the cap stiffener 111 due to the pressure of the oil, thereby blocking the inlet 114. Here, the check valve 140 is made of rubber. Alternatively, the check valve 140 may be formed of metal to facilitate recycling thereof.

Industrial Applicability As described above, an oil filter according to the present invention can filter a large amount of oil since it has a great pressure-withstanding capability, even if it is small. Accordingly, an oil filter according to the present invention can be applied to engines of various capacities.

In addition, since the oil filter of the present invention is made of metal as a whole, it can be easily discarded or recycled, thereby not polluting the environment. Also, since the filter pores are dense and uniform, foreign materials of a small size can be completely filtered.

Furthermore, since the filtered oil can stably be supplied to an engine, a piston in a cylinder moves smoothly so that vaporization and knocking due to high temperature, and fuel consumption are lowered, overload to a cooling fan and a water pump can be prevented, and noise can be reduced.

Claims

What is claimed is:

1. An oil filter comprising: a cap housing having a cap stiffener where an inlet and an outlet are formed; an element installed inside the cap housing, the element filtering oil flowing in through the inlet and exhausting the filtered oil through the outlet; a check valve installed between the cap stiffener and the element for preventing a reverse flow of oil out through the inlet; and a spring which is installed inside the cap housing for allowing the element to closely contact the cap stiffener, wherein the element comprises: upper and lower caps formed of metal; and a filter net installed between the upper cap and lower cap, the filter net being formed by weaving relatively thick metal wires and relatively thin metal wires together.

2. The oil filter of claim 1 , further comprising a safety valve including an inner cap, which protrudes from the lower cap toward the inside of the element and is provided with a through hole, a valve plate, which is installed at about the center of the inner cap to close or open a through hole of the lower cap, and a safety valve spring, which is installed .between the inner cap and the valve plate. . . _

3. The oil filter of claim 1 , wherein the diameter of the thick wire of the filter net is 0.2-0.4 mm, and that of the thin wire is 0.1-0.3 mm.

4. The oil filter of claim 3, wherein the diameter of a filter pore formed by the thick wire and the thin wire is 25-80 μm.

5. The oil filter of claim 1 , wherein the check valve is made of metal.