Variant length pleated filter element

• US 4,673,503 A
• Filed: 11/12/1985
• Issued: 06/16/1987
• Est. Priority Date: 07/18/1985
• Status: Expired due to Term

• Current Assignee: Tokyo Roki Co., Ltd.
• Original Assignee: Tokyo Roki Co., Ltd.
• Inventors: Fujimoto, Etsuo
• Primary Examiner(s): Fisher, Richard V.
• Assistant Examiner(s): Millard, Wanda L.
• Application Number:
  US06/799,168
• Time in Patent Office: 581 Days
• Field of Search: 210/493.1, 210/493.3, 210/493.5, 210/497.01, 210/497.2, 55/484, 55/489, 55/510, 55/521, 55/529, 55/488, 55/498
• US Class Current: 210/493.1
• CPC Class Codes: B01D 2201/122 with pleats of different length
• CPC Class Codes: B01D 2279/60 for the intake of internal combustion engines or turbines intake systems for vehicles comprising filters F02M35/024
• CPC Class Codes: B01D 29/21 with corrugated, folded or wound sheets
• CPC Class Codes: B01D 46/2411 Filter cartridges
• CPC Class Codes: B01D 46/522 with specific folds, e.g. having different lengths

Abstract

A filter element adapted to be incorporated in filter devices such as air filter, oil filter and fuel filter is disclosed which includes a pair of end plates and a filter material folded so as to form a series of pleats and disposed between the end plates to define a hollow cylinder having outer and inner circumferences. The space between the circumferences is divided into at least six areas to contain the pleats with symmetrical pattern. Each of the areas includes a group of the inner ridges, through which the pleats are connected to each other, arranged substantially along the pleat in the adjacent area to thereby vary the length of the pleats connected through the inner ridges of the group.

Claims

1. A filter element comprising a pair of end plates arranged in parallel with each other and a filter material disposed between said end plates to form a hollow cylinder having an outer circumference and an inner circumference, said inner and outer circumference cooperating to form an annular space, said inner and outer circumference cooperating to form an annular space, said filter material being folded so as to form a plurality of pleats connected to each other through outer ridges and inner ridges, wherein:

the space defined between said outer circumference and said inner circumference is divided into at least six areas to contain said pleats with symmetrical pattern with respect to the center of said hollow cylinder, said pleats in each said area being arranged substantially in parallel with each other at equal intervals, said outer ridges in each said area being arranged substantially at equal intervals along said outer circumference, and each said area including a first group of said inner ridges arranged substantially along one of said pleats in the adjacent area to thereby vary the length of said pleats connected through said first group of said inner ridges, and a second group of said inner ridges arranged substantially at equal intervals along said inner circumference whereby said pleats connected through said second group of said inner ridges have substantially the equal length.

2. A filter element comprising a pair of end plates arranged in parallel with each other and a filter material disposed between said end plates to form a hollow cylinder having an outer circumference and an inner circumference, said inner and outer circumference cooperating to form an annular space, filter material being folded so as to form a series of pleats connected to each other through outer ridges and inner ridges, wherein:

the space defined between said outer circumference add said inner circumference is divided into at least six areas to contain said pleats with symmetrical pattern with respect to the center of said hollow cylinder, said pleats in each said area being arranged substantially in parallel with each other at equal intervals, said outer ridges in each said area being arranged substantially at equal intervals along said outer circumference, and said inner ridges in each said area being substantially aligned with each other along a straight line extending in parallel with said pleats in the adjacent area, said straight line being tangent to said inner circumference to thereby vary the length of said pleats gradually from one side to the other side of said area.

3. A filter element comprising,

a pair of end plates arranged in a spaced apart, parallel relation with each other,

a filter material folded to form a plurality of pleats connected to each other through outer ridges and inner ridges, said filter material disposed between said end plates to form an annular hollow cylinder,

said annular cylinder having an inner periphery and an outer periphery and being divided into at least six areas to contain said pleats, said at least six areas arranged in a symmetrical pattern with respect to the center of said annular cylinder,

said pleats in each of said areas being arranged in a spaced apart, parallel relation to each other with the distance between adjacent pleats being substantially equal, said pleats in each of said areas being divided into at least first and second alternating variant length groups, the pleats in said first group having a substantially uniform length in the radial direction and having the inner ridges arranged substantially along said inner periphery, and the pleats in said second group diminishing in length toward the adjacent area and having the inner ridges substantially aligned with one of the pleats in the adjacent area.

4. A filter element comprising,

a pair of end plates arranged in a spaced apart, parallel relation with each other,

a filter material folded to form a plurality of pleats connected to each other through outer ridges and inner ridges, said filter material disposed between said end plates to form an annular hollow cylinder,

said annular hollow cylinder having an inner periphery and an outer periphery and divided into at least six areas to contain said pleats, said at least six areas arranged in a symmetrical pattern with respect to the center of said annular cylinder,

said pleats in each of said areas being arranged in a spaced apart, parallel relation to each other with the distance between adjacent pleats being substantially equal and arranged such that the outer ridges are substantially aligned with said outer periphery and the inner ridges are substantially aligned with a chord line that extends parallel to the pleats in the adjacent area and tangent to said inner periphery such that the pleats in each of said areas have diminishing lengths from one side of the area to the other side of the area.