Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
  • B01D29/11—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements
  • B01D29/114—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements arranged for inward flow filtration
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
  • B01D35/02—Filters adapted for location in special places, e.g. pipe-lines, pumps, stop-cocks
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
  • B01D35/14—Safety devices specially adapted for filtration; Devices for indicating clogging
  • B01D35/15—Bidirectional working filters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
  • B01D35/14—Safety devices specially adapted for filtration; Devices for indicating clogging
  • B01D35/157—Flow control valves: Damping or calibrated passages
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
  • B01D35/30—Filter housing constructions
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2201/00—Details relating to filtering apparatus
  • B01D2201/34—Seals or gaskets for filtering elements

Definitions

• the present invention relates to a hydraulic filter as defined in the preamble of claim 1.
• filters are generally known in the art. These filters, especially in the aftermarket appear to be problematic in the sense that they are operational only when mounted in one of two possible directions. Although various so called “fool proof means and indications on the filter have been devised in order to prevent incorrect mounting, users and assembly workers ever have proven to be able to ignore and even force such measures. Though the incident rate of such occurrences may be relatively low, the consequences in each case may be enormous in that the engine to by provided with filtered oil, at such occasions ends up with no oil at all and runs dry. This consequence is not only damaging to the vehicle and to its owner but in particular if felt to be at least potentially harmful for the image of the filter supplier, while also any direct consequences, e.g. of proving that the supplier is not liable may amount to serious costs.
• the filter may be mounted in either direction, be it at first time mounting or after repair.
• the novel filter unit is internally shaped symmetrically and leaves room for the filter element to shift between two end positions at which unfiltered passage of oil through the unit, other than through a bore at the axial ends of the filter element, is prevented. Rather, when shifted to the other end, i.e.
• the shift provides for a passage of oil between the axial end face at that entry side and the housing walls, so as to allow oil to enter an oil space radial exterior from the filter element. From this location it may enter the filter, however is prevented from passing towards the connection port of the filter unit away from the port that actually functions as entry port.
• the mentioned bore in each of the closure member allows connection from the interior space of the filter to said connection port remote from the actual entry port.
• the presence of such bore also enables the use of high efficiency micro-filter as stand alone or in-line filters, replacing conventional full flow filters, as is further explained in the remainder of the description.
• micro-filters are known per se, e.g. from WO- 0107142, and from the SAE paper 2001-01-0867 "Automatic transmission hydraulic system cleanliness - the effects of operating conditions, measurement techniques and high efficiency filters".
• Figure 1 is a view of a cross section along the longitudinal axis of the filter according to the invention, represented with a filter element positioned in an intermediate position within a filter housing;
• Figure 2 is a view in accordance with figure 1 , with the filter element indicated in one of its two operational positions;
• Figure 1 shows a filter unit 1 , comprising a filter housing 2, and a filter element 3 comprised therein moveably along its longitudinal axis between two axial end positions.
• the unit is provided with two connection ports 4, by which the unit may be coupled within a hydraulic connection line of a mechanical device such as an engine or transmission, requiring the oil filtered by the unit.
• the housing is in casu provided in two, virtually identical halves 5, of which the interiors are mirrored in the depicted mounted position.
• the one half 5 at it's exterior mounting parts slightly differs from the other by the presence of a groove 6 for an oil sealing means such as an O-ring in a flange part 7.
• Such groove may however in principle as well be divided in halves at each housing part 5.
• bores 8 are provided in the flange 7, which bores may in principle also be provided identical.
• the one halve 5 may further be provided with a centring boss 16, in casu conically and ring shaped, located at the most exterior side of the flange 7 for ease of assembly, while the other halve 5 is in such case provided with a complementary shaped receiving recess.
• each halve 5 is provided with a main cylindrical section 9 and a base section 10.
• the cylindrical section is intended to provide filter entry space for oil, i.e. an oil chamber 11 at the radial exterior of a generally cylindrical filter element 3, the use of which shape is widely accepted.
• the base section 10 of a housing part 5 comprises a relatively short cylindrical section 12 of smaller diameter than that of the main section 9.
• the depicted rectangular transition from main cylindrical section 9 to base cylindrical section 10 may alternatively favourably be provided conical.
• the base section further is provided with a conical section 13 of relatively short length, comparable to the length of the cylindrical section 12.
• the conical section transits to a radial end wall 15 of the housing, which comprises one of the two connection ports 4 of the filter unit.
• the filter element 3 is preferably formed as a by-pass filter, in particular a so- called in-depth filter.
• a micro-filter preferably cellulose based, however, various types of suitable media exist.
• the cellulose-based filter of Applicant is advantageous in that it provides a high efficiency filter. Most of such micro-filters are high density and require a relatively elevated pressure difference over the filtering material for reaching a maximum amount of flow through it.
• the depicted filter 3 comprises a cartridge of filtering material, provided over a perforated cylindrical core part 21 of which in this drawing only the axial end portions 23 are represented in cross section.
• the cylindrical core part 21 provides for an internal chamber 22 for receiving oil filtered by the element 3.
• the members closure members 25 are provided with one or more internal projections 26 circularly provided towards the filter element side for receiving and positioning the filter cartridge 20, i.e. the core part 21 thereof, such that the central core 21, by its end portions 23, may abut the radial exterior side of the projection 26.
• the closure member 25 preferably slightly extends to radial beyond the filter cartridge 20, and so as to protect the filter material from contacting the filter housing 2, e.g. the base part 10 thereof.
• an edge part 27 circumvents part of the filter material so as to further protect the filter material from contacting the housing 2, and so as to cover the axial contacting plane between closure element 25 and filter material 20, thereby also preventing the latter from being damaged by oil flow, and any possible local accelerations thereof.
• the closure elements 25 are, generally correspondingly with the conical transitions 13 at the interior of the housing parts 5, shaped conical at the axial end of the radial, i.e. cylindrical periphery that faces the radial wall 15 of the housing, i.e. that faces the relevant axial end of the unit 1. In this manner, the receipt of the filter element 3 within a base section 10 of a housing part 5 is promoted. Also in this manner, a oil seal may be realised, a cylindrical circumference part of the closure member 25 matching the inner circumference of cylindrical section 12 of the base part, in addition to the contact between the conical sections 13 and 28 of the housing part and of the filter element 3.
• an O-ring 29 is applied as part of the sealing means.
• the O-ring i.e. the groove for it is provided within at least part of the conical section 28 of a closure member 25.
• the conical sections 13 and 28 of housing part 5 and closure member 25 respectively slightly differing in angle, such that earliest mutual contact would occur at the radial most exterior side of these sections.
• the filter element 3 is located in one of its two axial end positions.
• a small amount of end space 14 may remain between the closure member 25 and the end wall 15 of the housing, this space than being in communication with the connection port 4 at the relevant end.
• the closure members 25, are further provided with a bore communicating with the interior chamber 23 of the filter element 3 on the one hand, and the interior of the housing 2, external to the filter element 3, at least indirectly with the connection port 4, i.e. possibly via the end space 14, at the axial side where the member 25 is included.
• the described feature of inversing the mounting position of the unit without any consequence for the functioning thereof holds true at first time of mounting the present unit and is unaffected by any loosening of the unit and subsequent remounting thereof.
• This feature favourably releases the manufacturer of providing extensive mounting instructions and of adding structures dedicated to prevent erroneous mounting direction of the filter element and thereby also is to the benefit of the buyer of the product.
• the presence of the bore 30 also promotes the possible use of micro-filters in the unit according to the invention.
• the bore 30 causes the additional pressure difference that is often required for a micro-filter to operate at full capacity, while at the same time it ensures a minimum flow of oil through the unit, be it unfiltered.
• an additional full flow filter - normally filtering as coarser grade and at a lower efficiency - may be used in addition to the filter fitted with a micro-filter.
• the efficiency of the micro- filter is of such larger order than conventional full flow filters, that even at passage of unfiltered oil through the unit, practically all of the oil will be filtered to a very fine degree within in a relatively short initial period, even without an additional full flow filter.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Lubrication Details And Ventilation Of Internal Combustion Engines (AREA)
• General Details Of Gearings (AREA)
• Filtration Of Liquid (AREA)
• Fluid-Pressure Circuits (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=32116379

Family Applications (2)

Family Applications Before (1)

Country Status (3)

Families Citing this family (3)

Family Cites Families (13)

• 2003
  • 2003-01-09 EP EP03075122A patent/EP1440719A1/de not_active Withdrawn
  • 2003-10-24 EP EP03758406A patent/EP1626795A2/de not_active Withdrawn
  • 2003-10-24 WO PCT/IB2003/004710 patent/WO2004037384A2/en not_active Application Discontinuation
  • 2003-10-24 AU AU2003274426A patent/AU2003274426A1/en not_active Abandoned
• 2004
  • 2004-01-01 WO PCT/IB2004/000001 patent/WO2004062768A1/en active Application Filing

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events