NZ247871A - Filter having tubular housing and filter cage with insert which substantially reduces filter volumetric capacity - Google Patents

Description

247871 PATENTS FORM NO. 5 Fee No. 4: $260.00 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No: 247871 Dated: 14 June 1993 FILTER UNIT We Alfa Laval (NZ) Limited, trading as Nu Pulse, a New Zealand company of 82 Greenwood Street, Hamilton, New Zealand hereby declare the invention for which We pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: This invention relates to filters. 247871 Traditionally milk filters used in milking plants have been manufactured of a tube-in-tube configuration and have large free spaces within the filter. At the end of milking the volume of free space within the filter means that there is considerable residue of millr left in the filter. The residue is commonly drained off to feed calves, or even discarded. With today's high prices for milk the volume of milk discarded in this way may represent a considerable loss to the farmer. Recent trends towards bigger milk lines and filters accentuate the situation.

It is an object of the present invention to provide a milk filter which will go some way to eliminating the residue problem referred to.

Further objects and advantages of the present invention will become apparent from the ensuing description which is given by way of example.

According to the present invention there is provided a filter comprising an elongate tubular housing, end caps for the housing, support means for co-axially supporting a filter cage with respect to one or other of the end caps, said filter cage defining exterior and interior regions within the filter, an inlet into the housing through which fluids can enter the exterior regions of the filter, and an outlet from the interior regions of the filter, one or other of the end caps supporting an insert which occupies a substantial portion of free space within the interior region of the filter and which substantially reduces the volumetric capacity of the filter.

The insert can be substantially cylindrical and is fixed to one of said end caps. As.'v~" '"•*<£ ;-c ;' ;The insert can be fabricated from tubular material. , - ?, >Yi ;\ i »'• ;247871 ;The filter cage can mount a filter sock. ;The end cap to which the insert is fixed can be provided with a sealable drainage outlet. ;Each of the end caps can include an end wall to which is mounted a tubular sealing ring, the filter cage comprising end supports which mount a cage body and which are releasably fixed to the sealing rings. ;Aspects _of the present invention will now be described in relation to the accompanying sectional drawing. ;With respect to the drawing the filter may comprise an elongate housing generally indicated by arrow 1, an upper end cap 2 and a lower end cap 3. A filter device generally indicated by arrow 4 which may comprise a cage and filter sock extends substantially co-axially within the housing 1 and a side wall inlet 5 and an upper end cup outlet 6 are also provided. ;An insert 7 is provided within the confines of the filter device 4. ;The caps 2 and 3 are of substantially similar configuration each having a bottom wall 8 and a flange 9 and each may be provided with gripping means 10. The caps 2, 3 can be a push, screw or other fit on the ends of the housing 1 and O-rings 11 can be provided as a means of sealing where the caps fit on the housing. ;In the example illustrated the caps 2, 3 provide support for a rubber seal ring 12 which provides end supports 13 for the filter device 4. The filter device 4 can comprise a cage with a filter sock surrounding the outer peripheries of the cage. ;The upper end cap 2 also mounts the outlet 6. The lower e;nd* cap • £•' 247871 provided with a drain plug 14 and in the illustrated example supports the insert 7 which substantially reduces the volume within the confines of the filter device 4.

Generally the filter is constructed of suitable metal such as stainless steel and/or a combination of metal and rubber or plastic parts where appropriate.

The insert 7 substantially reduces the volumetric capacity of the interior regions of the filter and reduces waste previously referred to which commonly occurs at the end of milking.

The end cap 3 mounting the insert can be used to replace existing end caps.

The insert 7 can be manufactured from tubestock and is provided with a closed end.

Each of the end caps 2, 3 have an end wall 15 to which rings 12 are mounted and the filter cage 4 comprises end supports 13 which mount the cage and which are releasably fixed at a complimentary push-fit tongue and groove arrangement 16 as shown to the rings 12.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

Claims (6)

WHAT WE CLAIM IS: 247871

1. A filter comprising an elongate tubular housing, end caps for the housing, support means for co-axially supporting a filter cage with respect to one or other of the end caps, said filter cage defining exterior and interior regions within the filter, an inlet into the housing through which fluids can enter the exterior regions of the filter, and an outlet from the interior regions of the filter, one or other of the end caps supporting an insert which occupies a substantial portion of free space within the interior region of the filter and which substantially reduces the volumetric capacity of the filter.

2. A filter as claimed in claim 1 wherein the insert is substantially cylindrical and is fixed to one of said end caps.

3. A filter as claimed in claim 2 wherein the insert is fabricated from tubular material.

4 A filter as claimed in any one of claims 1 to 3 wherein the filter cage mounts a filter sock.

5. A filter as claimed in any one of claims 2 to 4 wherein the end cap to which the insert is fixed is provided with a sealable drainage outlet.

6. A filter as claimed in any one of claims 1 to 5 wherein each of the end caps includes an end wall to which is mounted a tubular sealing ring, the filter cage comprising end supports which mount a cage body and which are releasably fixed to the sealing rings. 5 2^7871 A filter substantially as herein described with reference to the accompanying drawings. ALFA LAVAL (NZ\ LIMITED trading as NU PULSE NEW ZEAL A NT) LIMITED by their Attorneys JAMES & WELLS