Filter assembly

Details Filter assembly Filter assembly

2000-04-07

2001-05-01

Lithgow, Thomas M. (Department: 1724)

Liquid purification or separation

With heater or heat exchanger

For filter

C210S130000, C210S440000

Reexamination Certificate

active

06224758

ABSTRACT:

BACKGROUND OF THE INVENTION
The invention relates to a filter arrangement for a liquid to be filtered, with a bypass valve.
Oil filter arrangements for the filtration of the lubricant oil in a motor vehicle are known, in which a replaceable paper filter cartridge is inserted into the oil circuit. A central tube is inserted or snapped into the housing of the oil filter, and over it the hollow cylindrical filter cartridge is placed. The oil to be cleaned is conveyed to the exterior of the paper layers of the filter cartridge and flows through the filter cartridge and through the openings of the central tube, which is lattice-like as a rule, into the interior of the central tube, and from there through an outlet back into the oil circuit.
In order to assure a flow of oil even in the event of clogging or similar operational disturbances, a bypass valve is provided in a bypass passage in the filter arrangement, which opens if the pressure of the oil being filtered is too high, and assures a flow of oil to the outlet.
SUMMARY OF THE INVENTION
It is the object of the invention to further develop a filter arrangement of the kind described above in such a way that a simple manufacture and a compact construction can be achieved.
The filter arrangement of the invention has, in an advantageous manner, a bypass valve which is easy to integrate into the central tube of the filter arrangement during manufacture. For this purpose the central tube is provided with an annular constriction of its diameter, into the interior of which the bypass valve with the valve body and the valve spring can initially be loosely inserted.
As support for the valve body axially extending supports are arranged in the central tube behind the diameter constriction, wherein the supports have cut outs which are matched to the contour of the valve body with the spring in such a way that the supports function as a valve cover. In this stage of manufacture with the valve spring in the uncompressed state, the valve seat of the valve body, by which the sealing surface is produced after assembly is complete, extends slightly beyond the diameter constriction. The central tube, the diameter constriction and the star-shaped supports situated in the interior can be easily manufactured in one piece as an injection-molded synthetic resin part.
The functional bypass valve is formed in a simple manner by a valve plate which is durably fastened on the outside of the diameter constriction for sealing contact with the valve seat of the valve body against the pressure of the valve spring. The valve plate, which optionally may also be coated with elastomer at the valve seat, is advantageously produced of synthetic resin and is affixed to the diameter constriction of the central tube, for example by ultrasonic welding or spin welding or by crimping or by snapping by means of sealing lips.
In accordance with the invention, the bypass valve can be integrated into a simply produced central tube with just a few working steps. The valve body can initially be preassembled together with the valve spring and loosely inserted into the supports which function as a valve cover, and can then be secured in a single manufacturing step by attaching the valve plate.
The filter arrangement according to the invention thus makes an extremely compact construction possible with a simple manufacturing method, so that, when the filter arrangement is used in a conditioning unit for the lubricating oil in a motor vehicle, installation will be simple. For this purpose the filter arrangement with its housing cover can be attached onto a base body which contains an oil/coolant heat exchanger and a further bypass valve for the oil/coolant heat exchanger. Furthermore, an oil cooler is attached to the base body, preferably of aluminum or synthetic resin.


REFERENCES:
patent: 3142640 (1964-07-01), Otto, Jr.
patent: 5374355 (1994-12-01), Habiger et al.
patent: 5413712 (1995-05-01), Gewiss et al.
patent: 5538626 (1996-07-01), Baumann
patent: 5548893 (1996-08-01), Koelfgen
patent: 5589060 (1996-12-01), Gebert et al.
patent: 5695633 (1997-12-01), Ernst et al.
patent: 5888383 (1999-05-01), Cox
patent: 5888384 (1999-05-01), Wiederhold et al.
patent: 5895568 (1999-04-01), Koltunov
patent: 6068763 (2000-05-01), Goddard
patent: 6117312 (2000-09-01), Mees et al.
patent: 4240656 (1993-07-01), None
patent: 259594 (1988-03-01), None
patent: 580491 (1994-01-01), None
patent: 723796 (1996-07-01), None
patent: 773054 (1997-05-01), None
patent: 2465507 (1981-04-01), None

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