GB2031296A

GB2031296A - Liquid filter

Info

Publication number: GB2031296A
Application number: GB7927392A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-08-07
Filing date: 1979-08-06
Publication date: 1980-04-23
Also published as: ZA784468B; JPS5544388A

Abstract

An oil filter comprises a cup-like filter cartridge enclosing a spirally wound, axial flow paper filter element 34, demountably attached to a cast metal filter head 10 which includes an inlet port 18 and an outlet port 22, and a mounting flange 16 which is integral with the head for mounting the head on fixed structure. The cartridge has a threaded sleeve which screws on to boss 20 of the head, and bolt 39 assists in securing the cartridge to the head. <IMAGE>

Description

SPECIFICATION Liquid filter FIELD OF THE INVENTION This invention relates to a liquid filter for use particularly in filtering solids from a liquid such as oil.

SUMMARY OF THE INVENTION A liquid filter according to the invention includes a head adapted for mounting on fixed structure with the head including an inlet port and an outlet port, and a filter cartridge attached to the head and including a cylindrical housing, an axially located tube in the housing and a spirally wound paper filter in the housing between the tube and inner wall of the housing with one end of the tube in communication with the inlet port in the head and the other end located below the paper filter in a sump in the housing so that liquid flow through the filter in use is from the sump through the paper filter and into the head. Preferably, the paper of the filter is a cellulose paper which is heat treated prior to insertion in the cartridge to minimise the water content of the paper.

In one form of the invention the inlet port terminates in a threaded boss and the cartridge includes a threaded sleeve which is axially located in the tube and which is engaged with the boss.

Further according to the invention the cartridge housing includes a holed plate through which liquid may flow from the paper filter into the head.

Still further according to the invention means is provided in the sump of the cartridge housing to bias the paper filter into contact with the holed plate.

Preferably, corner seals are provided between the side wall of the housing and the holed plate and the tube and the holed plate and the paper filter is pressed into firm engagement with the seals to minimise liquid flow between the paper filter and housing wall and tube.

BRIEF DESCRIPTION OF THE DRAWING An embodiment of the invention will now be described by way of example with reference to the drawing which is a cross sectional side elevation of the filter of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The filter of the invention is shown in the drawing to consist of a head 10 and a filter cartridge 1 2.

The head is cast from metal and includes a mounting flange 16, an oil inlet port 18 which terminates in a threaded axially located boss 20 and an outlet port 22.

The cartridge 12 consists of a cylindrical metal housing 24 which includes an upper perforated plate 26 which carries a threaded sleeve 28, a peripheral channel member which carries a resilient compression seal 30, an axially located tube 32 and a spirally wound paper filter 34.

The free end of the tube 32 is open ended and terminates in a sump 36 in the base of the cartridge housing. A spider shaped bow spring 38 is located about the tube 32 in the sump and biases the paper filter 34 upwardly into firm engagement with the plate 26.

A bolt 39 passes through a hole in the wall of the sump and engages in a threaded bore in the boss 20. The bolt hole in the sump wall is sealed by a resilient seal which is located in a groove in the bolt washer. The bolt not only assists in holding the cartridge to the head but prevents pressure deformation of the cartridge housing 24.

The filter is made from cellulose paper which is densely wound into an annular form and which is heat treated to ensure a minimal moisture content. During the insertion of the paper filter into the cartridge housing the paper filter is compressed in a radial direction so that when in the housing it expands radially outwardly under the inherent resilience of the paper into firm sealing contact with the side wall of the housing and tube 32. Additionally, to ensure no oil bypass, circular quadrant seals 40 are located in the upper corners in the annular compartment in which the filter is located.

In use, the filter of the invention is operated as a bypass filter and oil under pressure is fed from the machine to which the filter is attached through the inlet port 18, down through the tube 32, upwardly through the paper filter 34 where solids entrained in the oil are trapped and through the holed plate 26 into the head and out of the outlet port 22.

An extremely important feature of the filter of the invention is the mounting flange 16 which is integral with the cast head 10. This arrangement enables the filter to be located in an accessible position in a vehicle engine compartment to facilitate cartridge replacement simply by undoing the bolt 39 and unscrewing the cartridge from the boss 20 in the head. The head is not removed from its mounting and the hydraulic lines connected to the ports 18 and 22 need not be interfered with during a cartridge change.

1. A liquid filter including a cast metal head having an inlet port and an outlet port, a flange on the head for securing the head to fixed structure, and a filter cartridge attached to the head and including a cylindrical housing, an axially located tube in the housing and a spirally wound paper filter in the housing between the tube and inner wall of the housing with one end of the tube in communication with the inlet port in the head and the other end located below the paper filter in a sump in the housing so that liquid flow through the filter in use is from the sump through the paper filter and into the head.

2. A filter as claimed in Claim 1 in which the paper of the filter is cellulose paper.

3. A filter as claimed in any one of the above claims in which the inlet port terminates in a threaded boss in the head and the cartridge includes a threaded sleeve which is axially located

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Liquid filter FIELD OF THE INVENTION This invention relates to a liquid filter for use particularly in filtering solids from a liquid such as oil. SUMMARY OF THE INVENTION A liquid filter according to the invention includes a head adapted for mounting on fixed structure with the head including an inlet port and an outlet port, and a filter cartridge attached to the head and including a cylindrical housing, an axially located tube in the housing and a spirally wound paper filter in the housing between the tube and inner wall of the housing with one end of the tube in communication with the inlet port in the head and the other end located below the paper filter in a sump in the housing so that liquid flow through the filter in use is from the sump through the paper filter and into the head. Preferably, the paper of the filter is a cellulose paper which is heat treated prior to insertion in the cartridge to minimise the water content of the paper. In one form of the invention the inlet port terminates in a threaded boss and the cartridge includes a threaded sleeve which is axially located in the tube and which is engaged with the boss. Further according to the invention the cartridge housing includes a holed plate through which liquid may flow from the paper filter into the head. Still further according to the invention means is provided in the sump of the cartridge housing to bias the paper filter into contact with the holed plate. Preferably, corner seals are provided between the side wall of the housing and the holed plate and the tube and the holed plate and the paper filter is pressed into firm engagement with the seals to minimise liquid flow between the paper filter and housing wall and tube. BRIEF DESCRIPTION OF THE DRAWING An embodiment of the invention will now be described by way of example with reference to the drawing which is a cross sectional side elevation of the filter of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The filter of the invention is shown in the drawing to consist of a head 10 and a filter cartridge 1 2. The head is cast from metal and includes a mounting flange 16, an oil inlet port 18 which terminates in a threaded axially located boss 20 and an outlet port 22. The cartridge 12 consists of a cylindrical metal housing 24 which includes an upper perforated plate 26 which carries a threaded sleeve 28, a peripheral channel member which carries a resilient compression seal 30, an axially located tube 32 and a spirally wound paper filter 34. The free end of the tube 32 is open ended and terminates in a sump 36 in the base of the cartridge housing. A spider shaped bow spring 38 is located about the tube 32 in the sump and biases the paper filter 34 upwardly into firm engagement with the plate 26. A bolt 39 passes through a hole in the wall of the sump and engages in a threaded bore in the boss 20. The bolt hole in the sump wall is sealed by a resilient seal which is located in a groove in the bolt washer. The bolt not only assists in holding the cartridge to the head but prevents pressure deformation of the cartridge housing 24. The filter is made from cellulose paper which is densely wound into an annular form and which is heat treated to ensure a minimal moisture content. During the insertion of the paper filter into the cartridge housing the paper filter is compressed in a radial direction so that when in the housing it expands radially outwardly under the inherent resilience of the paper into firm sealing contact with the side wall of the housing and tube 32. Additionally, to ensure no oil bypass, circular quadrant seals 40 are located in the upper corners in the annular compartment in which the filter is located. In use, the filter of the invention is operated as a bypass filter and oil under pressure is fed from the machine to which the filter is attached through the inlet port 18, down through the tube 32, upwardly through the paper filter 34 where solids entrained in the oil are trapped and through the holed plate 26 into the head and out of the outlet port 22. An extremely important feature of the filter of the invention is the mounting flange 16 which is integral with the cast head 10. This arrangement enables the filter to be located in an accessible position in a vehicle engine compartment to facilitate cartridge replacement simply by undoing the bolt 39 and unscrewing the cartridge from the boss 20 in the head. The head is not removed from its mounting and the hydraulic lines connected to the ports 18 and 22 need not be interfered with during a cartridge change. CLAIMS

3. A filter as claimed in any one of the above claims in which the inlet port terminates in a threaded boss in the head and the cartridge includes a threaded sleeve which is axially located in the tube and which is engaged with the boss.

4. A filter as claimed in any one of the above claims in which the cartridge housing includes a holed plate which forms a closure for the housing and through which liquid may flow from the paper filter into the head.

5. A filter as claimed in Claim 4 in which means is provided in the sump of the cartridge housing to bias the paper filter into contact with the holed plate.

6. A filter as claimed in either one of Claims 4 or 5 in which annular corner seals are provided between the side wall of the housing and holed plate and the tube and the holed plate and the paper filter is pressed into firm engagement with the seals to minimise liquid flow between the paper filter and housing wall and tube.

7. A filter as claimed in any one of the above claims in which the head includes a peripheral annular sealing surface and a seal is located between the surface and the cartridge.

8. A liquid filter as claimed in any one of the above claims including a bolt which passes through the sump and tube in the cartridge to engage a threaded bore in the head for holding the cartridge to the head.

9. A cast metal head for a filter cartridge including liquid inlet and outlet ports, with one of the ports terminating in an axially located boss which is threaded for engagement with a filter cartridge and a flange which is integral with the head for mounting the head on fixed structure.

10. A liquid filter substantially as herein described with reference to and as illustrated in the drawing.

11. A head for a liquid filter substantially as herein described with reference to and as illustrated in the drawing.

12. A cartridge for a liquid filter substantially as herein described with reference to and as illustrated in the drawing.