US3765690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite seal
Assignee: Scott Technologies Inc
•
Filing: 1971-01-21
•
Granted: 1973-10-16
•
Expires: 1991-01-21
Abstract
Abstract A pair of annular sealing members captively disposed in axial abutting relation about a reciprocating member and formed of synthetic plastic materials of different degrees of hardness. The softer member has total memory coupled with a quick response to accept severe deflection of the reciprocating member and the harder member, capable of enduring higher pressures, serves as a back-up for the softer member to prevent extrusion. The softer member moves relative to the harder member under high pressures in an arrangement relieving the frictional force acting against the sealing lip of the softer member and loading the harder member. In lighter duty applications a rod wiper can be combined with the harder member, and the harder member can be elongated for added bearing capability.
Inventors
- 👤 W Sievenpiper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:09
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/56
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
256 words
A composite seal for piston rods and the like comprising: a first annular member and a separate second annular member disposed in an axial abutting relation and captively retained about the outer surface of A relatively reciprocating member, said first and second annular members having portions, respectively, in sealing engagement with said reciprocating member, said first annular member being formed of a synthetic plastic material and said second annular member being formed of a synthetic plastic material of a higher durometer rating than said first member, said first annular member comprising a body terminating in an annular end face and said second annular member comprising a body having an annular abutment shoulder intermediate the opposite ends thereof facing said first member end face in axially spaced relation thereto under low pressure conditions, said members having coacting surfaces causing said first member to move relative to said second member under high pressure conditions with said first member end face approaching said second member shoulder and also causing said first annular member to be stretched radially outwardly thereby relieving the frictional force between said sealing engagement portion of said first member and the outer surface of said reciprocating member, said coacting surface of said first annular member comprising an annular inclined surface extending radially inwardly from said first annular body end face and the coacting surface of said second annular member comprising an annular inclined surface extending radially inwardly from said shoulder toward said first annular member and complementary to said inclined surface of said first annular member.
Claim 2
Dependent Claim
256 words
A composite seal for piston rods and the like comprising: a first annular member and a separate second annular member disposed in an axial abutting relation and captively retained about the outer surface of A relatively reciprocating member, said first and second annular members having portions, respectively, in sealing engagement with said reciprocating member, said first annular member being formed of a synthetic plastic material and said second annular member being formed of a synthetic plastic material of a higher durometer rating than said first member, said first annular member comprising a body terminating in an annular end face and said second annular member comprising a body having an annular abutment shoulder intermediate the opposite ends thereof facing said first member end face in axially spaced relation thereto under low pressure conditions, said members having coacting surfaces causing said first member to move relative to said second member under high pressure conditions with said first member end face approaching said second member shoulder and also causing said first annular member to be stretched radially outwardly thereby relieving the frictional force between said sealing engagement portion of said first member and the outer surface of said reciprocating member, said coacting surface of said first annular member comprising an annular inclined surface extending radially inwardly from said first annular body end face and the coacting surface of said second annular member comprising an annular inclined surface extending radially inwardly from said shoulder toward said first annular member and complementary to said inclined surface of said first annular member.
Claim 3
Dependent Claim
42 words
A composite seal according to claim 1 wherein said first annular member body is provided with a first and second annular flange at the end opposite said annular end face, said flanges being spaced apart radially and defining an annular groove therebetween.
Claim 4
Dependent Claim
31 words
A composite seal according to claim 2 wherein said first annular flange has an inclined inner wall portion terminating in a sealing lip having an interference fit with said reciprocating member.
Claim 5
Dependent Claim
66 words
A composite seal according to claim 2, in combination with an hydraulic actuator having a hollow cylindrical member encircling said reciprocating member, said hollow member having an annular wall cavity confining said seal with said first flange in sealing engagement with said reciprocating member and said second flange in sealing engagement with the cavity wall, said annular groove facing the high pressure side of said actuator.
Claim 6
Dependent Claim
34 words
A composite seal according to claim 1, wherein said radial stretching of said first member is accompanied by radial loading of said second member to increase the sealing engagement thereof against said reciprocating member.
Claim 7
Dependent Claim
79 words
A composite seal according to claim 1 in combination with a fluid cylinder having an outer member with said reciprocating member being relatively reciprocable therein, an annular groove formed in the inner surface of said outer member, said composite seal being captively retained in said annular groove, said first and second seal members being axially relatively movable to vary the relative action thereof under different pressure conditions, and said groove being of an axial dimension permitting such relative movement.
Claim 8
Dependent Claim
21 words
A composite seal according to claim 1 wherein said second annular member is provided with means for wiping said reciprocating member.
Claim 9
Dependent Claim
40 words
A composite seal according to claim 7 wherein said wiping means comprises a first annular flange extending generally axially from said second annular member in a direction away from said first annular member and adapted to wipe said reciprocating member.
Claim 10
Dependent Claim
70 words
A composite seal according to claim 8 wherein said wiping means includes a second annular flange extending generally axially from said second annular member in a direction away from said first annular member, said flanges being spaced apart radially thereby defining an annular groove therebetween, the spacing between said flanges increasing gradually in an axial direction from said second annular member, said first flange extending axially beyond said second flange.
Claim 11
Dependent Claim
35 words
A compOsite seal according to claim 1 wherein said second annular member is provided with an elongated generally cylindrical axial surface in slide bearing engagement with said reciprocating member to also function as a bearing.
Claim 12
Dependent Claim
54 words
A composite seal according to claim 10 wherein said second annular member is provided with an end portion having an annular flange extending generally axially from said second annular member in a direction away from said first annular member and having a surface extending from said axial surface adapted to wipe said reciprocating member.
Claim 13
Dependent Claim
38 words
A composite seal according to claim 1 wherein said end face and said abutment shoulder of said first and second annular members, respectively, are flat and lie in transaxial planes normal to the axes of said annular members.
Claim 14
Dependent Claim
55 words
A composite seal according to claim 1 wherein said second annular member body includes a first end face, a second end face of lesser area than said first face, said abutment shoulder being intermediate said end faces, said inclined surface of said second member extending radially outwardly from said second end face to said shoulder.
Claim 15
Dependent Claim
62 words
A composite seal according to claim 13 wherein said second annular member has an inner wall comprising a straight portion parallel to the axis of said second annular member, and an inclined portion extending from said straight portion in a direction slightly radially inwardly thereof and terminating in a lip in fluid sealing engagement with the outer surface of said reciprocating member.
References Cited (Backward Citations)
US2687335A
Cited
US2708573A
Cited
US2914369A
Cited
US3146683A
Cited
US3271038A
Cited
US3254898A
Cited
GB1019523A
Cited
US3606356A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |