GB2217223A

GB2217223A - Vacuum filter

Info

Publication number: GB2217223A
Application number: GB8908008A
Authority: GB
Inventors: Brian William Garn
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-04-09
Filing date: 1989-04-10
Publication date: 1989-10-25
Anticipated expiration: 2009-04-10
Also published as: GB2217223B; GB8908008D0; GB8808363D0

Abstract

Apparatus for batchwise filtering of thick liquids such as wall-paper paste or brewing liquor in volumes of the order of 1 to 5 gallons at a time comprises upper and lower chambers 24, 26 separated by a screening of filtering medium 12. Vacuum can be applied to the lower chamber by a domestic or industrial vacuum cleaner connected thereto via a hose and an associated end fitting 20 extending through a hole in the lid of the vacuum chamber and detachably securable to a wall of the upper chamber. A manually adjustable bleed valve permits selective reduction of the vacuum applied, if necessary. <IMAGE>

Description

SCREENING OR FILTERING APPARATUS This invention relates to apparatus for screening or filtering liquids, particularly, but not exclusively, such apparatus for batchwise screening or filtering of thick liquids such as wallpaper paste of brewing liquor, in volumes of the order of 1 to 5 gallons at a time.

Prior proposals in relation to apparatus for screening or filtering liquids includes, of course, chemical laboratory apparatus and chemical production and pilot production plant, together with simple hand sieves or screens.

While it is obviously perfectly possible to achieve screening or filtering of all types of liquids using the above-mentioned apparatus from chemical laboratories or chemical production or pre-production plant, such equipment is totally irrelevant so far as the requirements of mobile craftsman such as decorators are concerned.

I have established that there is a considerable advantage to be gained by screening wallpaper paste prior to the use of same, whereby the lumps which are inevitably formed during mixing are removed, whereby improved results are obtained and the undesirable presence of an uneven finish on the wall-paper is avoided.

In order to filter or screen thick liquids such as wallpaper paste, there appears to be presently available no suitable device which will carry out this function at a reasonable speed. Simple plain sieves or screens rapidly become blocked. The only other alternative appears to be to greatly extend the mixing time for the paste in an attempt to minimise the formation of lumps.

Accordingly, I have identified a considerable need for improved apparatus for screening or filtering liquids, and an object of the present invention is to provide such apparatus offering improvements in relation to one or more of matters discussed herein, or generally.

According to the invention there is provided apparatus for screening or filtering liquids as defined in the accompanying claims.

In a preferred embodiment apparatus for batchwise screening or filtering of thick liquids such as wallpaper paste or brewing liquor in volumes of the order of 1 to 5 gallons at a time comprises a screening or filtering medium mounted on support means therefor. An upper unstrained liquor receiving means is provided together with lower strained liquor receiving means. The latter is in the form of a vacuum chamber having said screening or filtering medium sealed thereto. Vacuum connection means is provided for removing air from the vacuum chamber.

The vacuum chamber has a removable lid which can be sealably mounted thereon. The filter medium is mounted to cooperate with an opening in the lid. The lid also forms or is fixed to the base of the upper liquid receiving means.

Both the upper and lower liquid receiving means are in the form of plastic buckets or the like, adapted for the purpose. The lid comprises flexible edge lip means which removably cooperates with the upper edge of the lower bucket to effect mechanical connection thereto and sealing cooperation therewith.

The vacuum connection means comprises quick attach/detach duct connection means adapted to be connected to the suction duct of a domestic or industrial vacuum cleaner. Adjustment means permits reduction of the vacuum applied to the vacuum chamber by selective opening to atmosphere of a vent in the vacuum connection means. The adjustment means comprises a manually positionable masking member cooperating with a vent hole in the vacuum connection means, the latter being connected to the vacuum chamber through the lid.

The plastic buckets are of downwardly-tapering frustoconical form and the lid connecting them thus comprises an annular portion bridging the diameter difference between the cooperating ends of the buckets, and the vacuum connection means comprises an opening formed in the lid to receive a connection tube connectible to a domestic vacuum cleaner.

The vacuum connection means comprises location means, such as a strap, to receive the upper end of the connection tube, the connection means being provided on an external side wall of the upper one of the buckets.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which Fig 1 shows a side elevation view of apparatus for screening or filtering of liquids, in its assembled condition; Fig 2 shows, somewhat diagrammatically and partly cutaway, a perspective view of the apparatus of Fig 1 with an internal screening element shown; Fig 3 shows a plan view of the apparatus of Fig 1, as viewed in the direction of arrow III in Fig 1; Fig 4 shows a bottom view of the apparatus of Fig 1, as viewed in the direction of arrow IV in Fig 1; Fig 5 shows a view of a portion of Fig 1 incorporating a modification; and Fig 6 shows a top view of the structure shown in Fig 5, the direction of viewing being indicated by arrow VI in Fig 5.

As shown in the drawings, apparatus 10 for batchwise screening or filtering of thick liquids such as wallpaper paste or brewing liquor in volumes of the order 1 to 5 gallons at a time comprises a screening or filtering medium 12 mounted on support means 14 therefor and having upper unstrained liquor receiving means 16, and lower strained liquor receiving means 18.

The lower strained liquor receiving means 18 is in the form of a vacuum chamber having the screening or filtering medium 12 sealed thereto and vacuum connection means 20 being provided for removing air therefrom.

Vacuum chamber 18 has a removable lid 22 which can be sealably mounted thereon, the filter or screening medium 12 being mounted to cooperate with a central opening in the lid, the lid also forming or being fixed to the base of the upper liquor receiving means 16.

Both of the upper and lower liquor receiving means are in the form of plastic buckets, 24, 26 respectively, adapted for this purpose.

As shown in Fig 1, lid 22 comprises flexible edge lip means 28 which removably cooperates with complementary edge lip means 30 at the upper edge of bucket 26 to effect mechanical connection thereto and sealing cooperation therewith.

Vacuum connection means 20 comprises a quick attach/detach duct connection means 32 adapted to be connected to the suction hose (not shown) of a domestic or industrial vacuum cleaner or the like. Connection means 32 may be the actual part manufactured by a vacuum cleaner manufacturer, and thus be provided with the usual bayonet type (not shown) quick-attach connector for connection to the flexible suction hose at its upper end. In the region of that same upper end the connection means 32 is located by a strap 34 in spaced relation to the upper bucket 24.

Strap 34 may be a rigid structure permanently holding connector 32 in position, or could be a resilient member whereby connector 32 is removably locatable in the position shown in the drawings. The lower end 36 of connector 32 extends through a hole in lid 22 to apply the vacuum to chamber 18. The hole is of such dimensions that the connector is a sealing fit therein.

As shown in Figs 5 and 6, adjustment means is provided to permit reduction of the vacuum applied to vacuum chamber 18 by selective opening to atmosphere of a vent in the vacuum connection means 20. The adjustment means 38 comprises manually positionable masking means 40 cooperating with a vent hole 42 formed in connector 32, whereby the vent hole can be completely covered or partially opened by sliding the masking means 40 lengthwise of duct 32. Masking means 40 is simply a suitable shaped slide member fitted around the oval cross-sectional shape of duct 32, as shown in Fig 6.

In Fig 1 there is shown a lid 44 to close the upper opening of bucket 24. This lid has edge seal means similar to that of the lower bucket 26, but is removed for the purpose of the plan view seen in Fig 3. As can be seen therein, the screen 12 is secured in the opening formed in the base of upper chamber 16 by a sewing technique employing copper wire 46 and an annular gasket 48 which seals the screen to the bucket 24 and lid 22 as a unitary assembly held together by the copper wire. Alternative assembly techniques include welding, bonding, and other known assembly techniques.

In use, connector 32 is coupled to the hose of a domestic vacuum cleaner and a vacuum is applied to chamber 18, thereby drawing air through screen 12. A liquid to be screened is poured into upper chamber 16 and effectively seals off the lower chamber by covering the screen, whereby the vacuum increases in the lower chamber, thereby drawing liquid rapidly through the screen. In this manner, thick liquids such as wallpaper paste can be very rapidly screened and lumps removed in a matter of seconds. If the vacuum applied by the vacuum cleaner is too great so that vacuum chamber 18 begins to be squeezed inwards, the vacuum can be reduced in a very simple manner by means of adjuster 40. The screened liquid is readily removed from lower bucket 26 by merely removing the lid 22 therefrom, which has the upper bucket 24 secured thereto.The screened liquid can then be readily poured into another container.

Alternatively, a duplicate container or bucket can be used in place of bucket 26.

Interestingly, the above embodiment provides simple effective and rapid screening or filtering means for liquids such as wallpaper paste. The apparatus employs a readily available source of vacuum. The volumes which can be handled are those commonly encountered in practical day-to-day operations by craftsman.

Amongst other modifications which could be måde in the above embodiment while remaining within the scope of the invention are the use of an alternative source of vacuum, including a manually operated vacuum pump. Many different types of screening or filtering medium may be employed according to the viscosity of the liquid concerned, and its nature. It is also to be understood that references herein to "sealing" are not to be interpreted as limited to a fluid-tight seal, but merely to the provision of sufficient sealing to achieve the purposes of the invention.

The buckets 24, 26 may be provided with suitable carrying handles (not shown).

Claims

1 Apparatus for batchwise screening or filtering of liquids such as wall-paper paste or brewing liquor in volumes of the order of 1 to 5 gallons at a time, the apparatus comprising a screening or filtering medium mounted on support means therefor and having upper unstrained liquid receiving means and lower strained liquid receiving means, characterised in that said lower strained liquid receiving means is in the form of a vacuum chamber having said screening or filtering medium sealed thereto, and vacuum connection means for removing air therefrom.

2 Apparatus for screening or filtering liquids characterised by a vacuum chamber having a screening or filtering medium sealed thereto and vacuum connection means for removing air therefrom.

3 Apparatus according to claim 1 or claim 2 characterised in that said vacuum chamber has a removable lid which can be sealably mounted thereon, said filter medium being mounted to cooperate with an opening in said lid.

4 Apparatus according to claim 3 characterised in that said lid also forms or is fixed to the base of said upper liquid receiving means.

5 Apparatus according to any one of claims 1 to 4 characterised in that both said upper and said lower liquid receiving means comprise plastic buckets or the like, adapted for the purpose.

6 Apparatus according to claim 5 when dependent on claim 3, characterised in that said lid comprises flexible edge lip means which removably cooperates with the upper edge of said lower bucket to effect mechanical connection thereto and sealing cooperation therewith.

7 Apparatus according to any one of the preceding claims characterised in that said vacuum connection means comprises quick attach/detach duct connection means adapted to be connected to the suction duct of a vacuum cleaner or the like.

8 Apparatus according to claim 7 characterised in that said vacuum connection means comprises adjustment means permitting reduction of the vacuum applied to said vacuum chamber by selective opening to atmosphere of a vent in said vacuum connection means.

9 Apparatus according to claim 8 characterised in that said adjustment means comprises a manually-positionable masking means to cooperate with a vent hole in said vacuum connection means.

10 Apparatus according to any one of claims 7 to 9 when dependent upon claim 3 characterised in that said vacuum connection means is connected to said vacuum chamber through said lid.

11 Apparatus according to claim 10 characterised in that said plastic buckets are of downwardly-tapering frustoconical form and said lid comprises an annular portion bridging the diameter difference between the cooperating ends of the buckets, and said vacuum connection means comprises an opening formed in said lid to receive a connection tube connectible to a vacuum cleaner, or the like.

12 Apparatus according to claim 11 characterised in that said vacuum connection means comprises location means, such as a strap, to receive the upper end of said connection tube, said location means being provided on an external side wall of the upper one of said buckets.

13 Apparatus for batchwise screening or filtering of liquids such as wall-paper paste of brewing liquor, substantially as described herein with reference to the accompanying drawings.

14 Apparatus for batchwise screening or filtering of liquids comprising apparatus according to any one of the preceding claims in combination with vacuum cleaning apparatus or the like capable of being quickly connected and disconnected to said vacuum chamber.