GB2134807A

GB2134807A - Liquid filter

Info

Publication number: GB2134807A
Application number: GB08303432A
Authority: GB
Inventors: Howard William Morgan
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-02-08
Filing date: 1983-02-08
Publication date: 1984-08-22
Also published as: GB2134807B; GB8303432D0

Abstract

A liquid filter includes a housing 12 with a removable top cover 20, an outlet 24 and an inlet 22 which is extended by an upturned impervious section 27 on which is seated a removable filter element 26. The element 26 is designed so that it can be removed without spilling unfiltered liquid into the clean side of the housing. In Fig. 3 the element 26 comprises a perforate basket enclosing an impervious sleeve 30, which effectively extends section 27 and defines an annular sludge- collecting space with the basket. In another construction, the section 27 is extended upwards inside sleeve 30. In a further construction, the filter is a simple perforate sleeve with a non- return valve at its lower end, seated on section 27, and its upper end seated on a flange around the top of the housing. <IMAGE>

Description

SPECIFICATION Liquid filter This invention relates to a filter for straining liquids or similar fluids, and in particular to a liquid filter having a removable filter element.

The present invention provides a liquid filter comprising a housing including side and base walls and having a top opening spaced from the base wall, a removable cover spanning the top opening, inlet and outlet ports in the housing, one of said ports including a liquid-impervious upturned section terminating in an open upper end within the housing and spaced from the other of said ports, a removable filter element located within the housing in contact with the upturned section and including a liquid-pervious part, the filter element, liquid-pervious part being located in the liquid flow path between said ports, whereby liquid directed through the inlet port passes through the filter element liquid-pervious part and the upturned section and out through the outlet port.

The construction of the upturned part of the filter housing is such that, when the filter element is removed for cleaning purposes, no dirty fluid mixes with the filtered or clean fluid within the housing. Moreover, the filter element confines the fluid within the filter element, reducing residue build-up at the base of the housing.

Advantageously, said one port is the inlet port, and the filter element is of one-piece construction.

Conveniently, the upturned section has a lower end contacting the housing base wall, and an upper end spaced from the top opening, the upper end supporting the filter element.

In a preferred embodiment, the filter element includes an inner sleeve member of liquidimpervious material, and an outer sleeve member spaced from the inner sleeve member by a connecting lower wall part, the outer sleeve member and/or the lower wall part being liquid pervious to provide filtration of the liquid.

Preferably, the filter element is removably supported on the open upper end of the upturned section of the inlet port with the interior of the inner sleeve member and the upturned section in liquid communication, and with the upper end of the inner sleeve member spaced from the cover, whereby liquid directed through the inlet port passes upwardly through the interior of the inner sleeve member, over the upper end of the inner sleeve member into the space between the inner and outer sleeve members, out through the outer sleeve member and/or the lower wall part into the interior of the housing, and out of the outlet port.

The outer sleeve member may be made of liquidpervious material.

Advantageously, the cover includes an inner raised portion which is upwardly offset from the top opening and overlies the upper end of the inner sleeve member to provide a liquid flow path into the filter element between said sleeve members.

The housing and/or the cover may contact the upper end of the outer sleeve member to provide a liquid seal at the outer sleeve member. In either case, the housing may include a shoulder, and the upper end of the outer sleeve member may include an out-turned flange supported upon said shoulder.

In another preferred embodiment, the filter further comprises retainer means for securing the cover in its closed position spanning the housing top opening, the retainer means being anchorable relative to the housing and extending through the filter element to the cover, releasable attachment means being provided for securing the retainer means to the cover in its closed position.

Advantageously, the retainer means includes a rod having the lower end thereof attached to the base wall, the rod extending upwardly within the upturned section and through the filter element inner sleeve member, the upper end of the rod being secured by the attachment means to the cover. In this case, the cover may have an opening extending from its inner surface to its outer surface, the rod extending upwardly through the opening in the cover, and the attachment means bearing against the outer surface of the cover for retaining the cover in its closed position.

Advantageously, the upturned section of the inlet port is cylindrical, and the inlet port includes a pipe section extending through the housing side wall and into the cylindrical upturned section above its lower end. Preferably, the outlet port extends from the housing side wall in alignment with the inlet port pipe section.

The filter element liquid-pervious part may include an annular reticulated wall, the reticulated wall extending upwardly from the upturned section towards the cover, the reticulated wall defining a cylinder having upper and lower openings, the lower opening being in liquid communication with the upturned section, a valve spanning the lower opening for preventing liquid flow through said cylinder lower opening to the upturned section and permitting liquid flow from the upturned section into the cylinder.

Preferably, the valve includes a hinged, fluidimpervious base wall forming part of the filter element, said base wall being movable in response to the direction of liquid flow between a first position in which it spans said cylinder lower opening and a second position spaced from said cylinder lower opening.

Conveniently, the filter element includes a lower wall which is supported on a flange attached to the upturned section.

This liquid filter allows economical and efficient cleaning of the filter element, and allows efficient removal of the filter element without mingling of clean and dirty fluid within the filter housing.

Moreover, the filter element closes to prevent intermingling of clean and dirty liquid as the filter element is removed from the filter housing.

Another advantage of this filter is that its cover is retained in a position spanning the housing top opening in a simple and economical way, even through the cover may be quickly and safely removed from this position.

Four forms of liquid filter, each of which is constructed in accordance with the invention, will now be described, by way of example, with reference to the accompanying drawings, in which:~ Fig. 1 is a side elevation of the first form of liquid filter; Fig. 2 is a fragmentary plan view of the filter of Fig. 1, with a portion of the cover cut away; Fig. 3 is a cross-section taken on the line 3-3 of Fig. 2; Fig. 4 is a fragmentary cross-sectional view of the housing of the filter of Fig. 1 with the cover removed and the filter basket raised; Fig. 5 is a cross-sectional view similar to that of Fig. 3 showing the second form of liquid filter; Fig. 6 is a cross-sectional view similar to that of Fig. 5 showing the third form of liquid filter;; Fig. 7 is a cross-sectional view similar to that of Fig. 6 showing the fourth form of liquid filter with its filter element in the inoperative position; and Fig. 8 is a cross-sectional view of the embodiment of Fig. 7 showing the filter element in its operative position.

Referring to the drawings, Figs. 1 to 4, show a filter 10 having a housing 12, defined by side wall 14 and a base wall 16, and a removable cover 20 which spans a top opening 18 in the housing. The housing 12 includes an inlet port 22, through which fluid enters, and an outlet port 24, through which filtered fluid exits.

The inlet port 22 includes an upturned, inner cylindrical part 27, which is sealed at its lower edge by contact with the housing base wall 1 6. A cylindrical filter basket 26 rests upon the upper edge 29 of the cylindrical part 27.

The filter basket 26 includes an inner sleeve member 30, an outer sleeve member 34 and a connecting lower wall part 32. The inner sleeve member 30 is made of fluid-impervious material, and serves to direct the fluid as it passes through the inlet port 22 and over its upper lip 31 into the basket 26 between the inner sleeve member 30 and the outer sleeve member 34. The outer sleeve member 34 is made of fluid-pervious or reticulated material, and serves to perform the fluid filtering function. The lower wall part 32 is fluid impervious, but may be pervious if desired.

The upper edge of the basket outer sleeve member 34 is formed into an out-turned flange 36, which rests upon a seal 39 and an annular shoulder 38 forming part of the housing side wall 14 adjacent to the opening 18.

The cover 20, which spans the housing opening 1 8, overlies the outer sleeve member flange 36 so as to anchor the basket 26 securely within the housing 12. Alternatively, the weight of the basket 26 may be sufficient to anchor it without the aid of the cover 20.

The location of the upper edge 31 of the inner sleeve member 30 varies with the type of cover used with the housing 12. As shown in Fig. 4, the cover 20 includes a domed or raised centre 21.

The inner sleeve member 30 is shown positioned near the level of the housing opening 18 to allow fluid to pass over the upper edge 31 of the basket inner sleeve member 30. Alternatively, the inner sleeve member 30 could extend upwardly above the top opening 18 and into the cavity of the cover centre 21.

The fluid, as shown by the arrows 40, enters the housing 12 through the inlet port 22, where it is directed upwards into the inner sleeve member 30 by the cylindrical part 27. The fluid then flows over the inner sleeve member edge 31, into the basket 26, and out through openings 35 in the outer sleeve member 34 into the bottom of housing 12, where it exits through the outlet port 24.

To change or clean the basket 26, the cover 20 is removed by loosening its hold-down nuts 15.

Ths basket 26 is then pulled upwardly (as seen in Fig. 4) away from the housing 12, with the filtered or strained material remaining within the basket.

In some operations, it may be desirable to use a flexible filter bag in addition to the rigid basket 26.

Fig. 5 shows the second form of liquid filter 10'.

This filter 10' is generally similar to the filter of Figs. 1 to 4, and so like reference numerals will be used for like parts, and only the modified parts will be described in detail. Thus, the filter 10' has a cover 20' which is retained in its operative position spanning the housing opening 18 in a different manner from that in which the cover 20 of the filter 10 is retained in its operative position.

The cover 20' has an inner surface 42 and an outer surface 44. An opening 46 in the cover 20' passes from the inner surface 42 to the outer surface 44, and lies on an axis which coincides with the vertical axis of the filter basket 26 and the cylindrical part 27. A rod 48 is attached at one end part 49 to the housing base wall 16, and extends upwardly from the base wall within the filter basket 26 and the cylindrical part 27. The other end part 50 of the rod 48 projects through the cover opening 46. The end part 50 of the rod 48 is threaded. A liquid seal 52 fits over the rod end part 50, and is located against the cover outer surface 44. A nut 54, or other fastening device, is threaded onto the rod end part 50, and against the seal 52, compressing the seal against the cover outer surface 44. The cover 20' is thus retained in its closed position spanning the housing top opening 18 and overlying the outer sleeve member flange 36 of the basket 26. The cover 20' may be removed by turning the nut 54 off the rod end part 50, and lifting the cover from the top opening 18 of the housing 12. The hold-down nuts 1 5 used with the cover 20 of the filter 10 of Figs. 1 to 4 are not required with the construction of the filter 10'.

Fluid can enter the housing 12 of the filter 10' through the inlet port 22, where the cylindrical part 27 directs it upwards into the inner sleeve member 30. The fluid then flows over the inner sleeve member edge 31, into the basket 26 and out of the openings 35 therein into the bottom of the housing 12, where it exits through the outlet port 24.

Fig. 6 shows the third form of liquid filter 10".

The filter 10" has a housing 12 including an outlet port 61 and an inlet port 63. The inlet port 63 includes an upturned cylindrical part 27', which is sealed at its lower edge against the housing base wall 16, and extends at its upper end 56 upwardly to near the level of the housing opening 1 8. The cylindrical part 27' includes a lower portion 58, and an upper portion 60 and having a smaller diameter than the lower portion and joined thereto by a shoulder 65. An annular wall 62 extends upwardly from the outer diameter of the shoulder 65, and carries and annular seal 64 in a groove 66 at its upper end. The filter basket inner sleeve member 30 fits over the cylindrical part upper portion 60 in a slide fit, and the basket 26 seats in fluid-sealing contact with the seal 64, with its lower wall part 32 upon the wall 62.The inner sleeve member 30 of the filter basket 26 extends upwardly towards the upper end 56 of the cylindrical part upper portion 60. In this embodiment, upon removal of the filter basket 26, overflow of unfiltered liquid from the cylindrical part 27' into the filter housing at the outlet port 61 is prevented.

Figs. 7 and 8 show the fourth form of liquid filter 10"', this filter being a modified form of the filter 10 of Figs. 1 to 4. The modification is to the filter element 26', which has only a reticulated side wall 68, and includes a hinged liquidimpervious base wall 71 which, when closed, spans the upper end 29 of the housing cylindrical part 27. The upper edge of the filter element side wall 68 is formed into an outturned flange 69, which rests upon the shoulder 38 of the housing side wall 14 and the seal 39. A cover 21 extends across the top opening 18 in the housing, and holds down the filter element 26'. Hold-down nuts 1 5 (only one of which is shown) secure the cover 21 to the housing 12.

In use, fluid enters the filter 10"' through the inlet port 22, and is directed upwardly within the housing 12 by cylindrical part 27 (as indicated by the arrow 74). The force of the fluid urges the wall 71 upwards, opening the filter element 26'. The fluid then flows through the reticulated side wall 68 of the filter element 26', into the housing 12, and out of the housing through the outlet 24 (as indicated by the arrows 75). The base wall 71 of the filter element 26' closes by itself when fluid flow through the filter stops. With the filter element wall 71 closed, the filter element 26' can be removed without unfiltered fluid escaping from the filter element and mixing with any filtered fluid which may remain within the housing 12.

Claims

1. A liquid filter comprising a housing including side and base walls and having a top opening spaced from the base wall, a removable cover spanning the top opening, inlet and outlet ports in the housing, one of said ports including a liquidimpervious upturned section terminating in an open upper end within the housing and spaced from the other of said ports, a removable filter element located within the housing in contact with the upturned section and including a liquidpervious part, the filter element liquid-pervious part being located in the liquid flow path between said ports, whereby liquid directed through the inlet portion passes through the filter element liquid-pervious part and the upturned section and out through the outlet port.

2. A liquid filter as claimed in claim 1, wherein the upturned section has a lower end contacting the housing base wall, and an upper end spaced from the top opening, the upper end supporting the filter element.

3. A liquid filter as claimed in claim 1 or claim 2, wherein said one port is the inlet port.

4. A liquid filter as claimed in claim 3, wherein the filter element includes an inner sleeve member of liquid-impervious material, and an outer sleeve member spaced from the inner sleeve member by a connecting lower wall part, the outer sleeve member and/or the lower wall part being liquid pervious to provide filtration of the liquid.

5. A liquid filter as claimed in claim 4, wherein the filter element is removably supported on the open upper end of the upturned section of the inlet port with the interior of the inner sleeve member and the upturned section in liquid communication, and with the upper end of the inner sleeve member spaced from the cover, whereby liquid directed through the inlet port passes upwardly through the interior of the inner sleeve member, over the upper end of the inner sleeve member into the space between the inner and outer sleeve members, out through the outer sleeve member and/or the lower wall part into the interior of the housing, and out of the outlet port.

6. A liquid filter as claimed in claim 4 or claim 5, wherein the outer sleeve member is made of a liquid-pervious material.

7. A liquid filter as claimed in any one of claims 4 to 6, wherein the cover includes an inner raised portion which is upwardly offset from the top opening and overlies the upper end of the inner sleeve member to provide a liquid flow path into the filter element between said sleeve members.

8. A liquid filter as claimed in any one of claims 4 to 7, wherein the housing contacts the upper end of the outer sleeve member to provide a liquid seal at the outer sleeve member.

9. A liquid filter as claimed in any one of claims 4 to 8, wherein the cover contacts the upper end of the outer sleeve member to provide a liquid seal at the outer seal member.

10. A liquid filter as claimed in claim 8 or claim 9, wherein the housing includes a shoulder, and the upper end of the outer sleeve member includes an out-turned flange supported upon said shoulder.

11. A liquid filter as claimed in any one of claims 4 to 10, further comprising retainer means for securing the cover in its closed position spanning the housing top opening, the retainer means being anchorable relative to the housing and extending through the filter element to the cover, releasable attachment means being provided for securing the retainer means to the cover in its closed position.

12. A liquid filter as claimed in claim 11, wherein the retainer means includes a rod having the lower end thereof attached to the base wall, the rod extending upwardly within the upturned section and through the filter element inner sleeve member, the upper end of the rod being secured by the attachment means to the cover.

13. A liquid filter as claimed in claim 12, wherein the cover has an opening extending from its inner surface to its outer surface, the rod extending upwardly through the opening in the cover, and the attachment means bearing against the outer surface of the cover for retaining the cover in its closed position.

14. A liquid filter as claimed in any one of claims 3 to 13, wherein the upturned section of the inlet port is cylindrical, and wherein the inlet port includes a pipe section extending through the housing side wall and into the cylindrical upturned section above its lower end.

15. A liquid filter as claimed in claim 14, wherein the outlet port extends from the housing side wall in alignment with the inlet port pipe section.

16. A liquid filter as claimed in any one of claims 1 to 15, wherein the filter element liquidpervious part includes an annular reticulated wall, the reticulated wall extending upwardly from the upturned section towards the cover, the reticulated wall defining a cylinder having upper and lower openings, the lower opening being in liquid communication with the upturned section, a valve spanning the lower opening for preventing liquid flow through said cylinder lower opening to the upturned section and permitting liquid flow from the upturned section into the cylinder.

17. A liquid filter as claimed in claim 16, wherein the valve includes a hinged, fluidimpervious base wall forming part of the filter element, said base wall being movable in response to the direction of liquid flow between a first position in which it spans said cylinder lower opening and a second position spaced from said cylinder lower opening.

18. A liquid filter as claimed in any one of claims 1 to 17, wherein the filter element is of one-piece construction.

19. A liquid filter as claimed in any one of claims 1 to 18, wherein the filter element includes a lower wall which is supported on a flange attached to the upturned section.

20. A liquid filter substantially as hereinbefore described with reference to, and as illustrated by, Figs. 1 to 4, Fig. 5, Fig. 6, or Figs. 7 and 8 of the accompanying drawings.