DE2148257A1 - LIQUID FILTER - Google Patents

Description

2U8257

E. 546
September 23, 1971 My / V / u

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Patent and

Username Auxiliary Registration

ROBERT BOSCH GMBH, Stuttgart Liquid filter

The invention relates to a liquid filter with an in
Housing arranged, axially flowed through Vickelelemont made of at least one spiral wound around a riitLelrchr papi.eruahrj, which is rolled up with the addition of sealants and two "spirally i ^ inej.n each other, forms accessible spaces." Lirrigei Lcn.

3098U / 0456

-2- 2U8257

Robert Bosch GMBH '

Stuttgart · R. 5 ^ 6 My / Wu

For filtering fuel, stage filters are known in which two individual box filters with different filter materials are arranged on a common cover and the coarse and fine filter stages are flowed through one after the other. Such Step filters, in which the fine filter step usually has a roll of filter paper through which there is an axial flow, are complex and take up a lot of space.

A single filter is also known (US-P3 3 283 908), in the one with a radial flow-through sternoincatz made of paper Coarse filter stage is connected upstream. For this purpose there is a space between the star insert and a cylinder surrounding it filled with small cotton balls that act as depth filters. Such an arrangement cannot be applied to a single filter transferred with a paper wrap insert, as the small cotton balls in the crevices on the face of a paper wrap would invade.

The object of the invention is to design a liquid filter with a paper winding insert as simply and space-savingly as possible, that its service life is improved.

According to the invention this is achieved in that in the housing on one end face of the winding element to the ball element upstream coarse filter line :: ent is arranged.

In this way z. B. when used as a fuel filter Particles of asphalt and wax left behind during filtration of fuel as a fine filter arboitei; df> n Papierwickc] use would block relatively quickly. Coarse filter rejected and thereby the service life of the liquid filter :.} increased considerably. The coarse filter can already be used for one

309814/0456

BATH ORIGINAL

- 3 - "2U8257

Robert Bosch GmbH _R ^. - _{/ w}

Stuttgart ^K ^ ^{b ny / Wu}

existing liquid filter without a lot of material and space to be provided.

Particularly useful refinements of the inventive concept emerge from the subclaims and the description.

An embodiment of the inventive concept is shown in the drawing, which partially shows a filter box in the Section shows.

The filter box 10 shown has a cup-shaped housing 11 which is closed at its open end with a cover 12. The cover 12 has a central hole 13, from which a central tube 14 leads downwards, as well as additional openings 15.In the annular space between the housing 11 and the central tube 14 there is a winding element 16 made of spirally wound filter paper, which sits on a perforated support plate 17. A coarse filter element 18, which largely fills the space formed between the winding element 16, the cover 12, the housing 11 and the central tube 14, rests on the winding element 16 on the end face opposite the support plate 17. The coarse filter element 18 consists of a; Felt strips 19 and a carrier strip 20, which are connected to one another and rolled up spirally. The carrier strip 2Q. can expediently consist of plastic, impregnated fabric or paper. A simple connection of felt and carrier strips 19 ₅ 20 to one another is possible by gluing or needles. Such strips can be produced efficiently and formed into a felt ring by subsequent winding under a relatively small tensile stress, which is then placed directly on the end face of the winding element 16.

309814/0456

-4- 2U8257

Robert Bosch GmbH r> c / ic μ / u

Stuttgart ^{R 546 My / Wu}

The structure of the coarse filter element 18 is relatively simple and gives it such stability that no additional Support plates for the winding element 16 or for the cover 12 are required.

During operation, the fuel flowing in through the openings 15 is in the coarse filter element 18 largely freed from such components that a relatively quick blocking of the as Fine filter working winding element 16 were cause. Such components are e.g. B. asphalt or wax particles. The fuel then flows axially through the winding element 16 and finally via the central tube 14 and the opening 13 cleaned off. The service life for the winding element 16 is much improved in this way.

A wool or plastic can be used to produce the felt ring fleece or a material suitable for the respective purpose can be used.

3088U / 0456

Claims (6)

-5- 2U8257 ^Β · Claims Liquid filter with a arranged in a housing, axially flowed through winding element of at least one filter paper web wound spirally around a central tube, which is rolled up with the addition of sealants and two spirally inelnaniergejoined, forms accessible spaces from opposite end faces, thereby characterized in that i »housing (11) on one end face of the winding element (16) is arranged a coarse filter element (18) connected upstream of the winding element. 2. A liquid filter according to claim 1, characterized in that the coarse filter member (18) is designed as a flat felt ring. J. Liquid filter according to claim 2, characterized in * that the felt ring is a spirally wound strip of felt having. 4. Liquid filter according to claim; $, characterized in that that the felt strip (19) kit edneiri tracer: tires (20) allied «« is. 309814/0456 BATH ORIGINAL Robert Bosch GmbH _α Stuttgart ^H 5. Liquid filter according to claim 4, characterized in that the pill strip (19) is needled onto the carrier strip (20). 6. Liquid filter according to claim 3 «characterized in that the felt ring (18) directly on the wound filter element (16) is applied 309814/0456