US4214507A
Expired / Lapsed
US
⏱️ 0.0 years remaining
One-piece plastic piston
Assignee: Individual
•
Filing: 1977-08-24
•
Granted: 1980-07-29
•
Expires: 1997-08-24
Abstract
Abstract A piston comprising a core molded from a rigid thermoplastic material and a seal element molded on the core from a flexible thermoplastic material to form a unitary assembly.
Inventors
- 👤 Jules M. Hock
- 👤 Donald S. de Vries, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:03
CPC Classifications
F; F16; F16J; F16J1/00; F16J1/005; F16J1/006; F16J1/008; B; B29; B29C; B29C45/00; B29C45/16; B29C45/1676; F16J15/00; F16J15/16; F16J15/32; F16J15/3268; B29C2045/1681; B29C37/00; B29C37/0078; B29C37/0082; B29C37/0085; B29K; B29K2075/00; B29K2077/00; B29K2105/00; B29K2105/06; Y; Y10; Y10S; Y10S277/00; Y10S277/924; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31565
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
134 words
A unitary piston comprising: a core molded from a rigid thermoplastic material, said core consisting of a disc-shaped member having opposite sides and a radially extending flange at the perimeter thereof spaced axially inwardly from said sides, said flange having a plurality of holes extending therethrough; and a seal element made from a flexible thermoplastic material molded on said core, on at least opposite sides of said flange and on said perimeter, the material of said seal element extending through said holes in said flange to connect the material on said opposite sides to form a mechanical bond between said seal element and said core, there being no adhesion or chemical bond between said core and said seal element, said mechanical bond being the only means for holding said seal element on said core.
Claim 2
Dependent Claim
134 words
A unitary piston comprising: a core molded from a rigid thermoplastic material, said core consisting of a disc-shaped member having opposite sides and a radially extending flange at the perimeter thereof spaced axially inwardly from said sides, said flange having a plurality of holes extending therethrough; and a seal element made from a flexible thermoplastic material molded on said core, on at least opposite sides of said flange and on said perimeter, the material of said seal element extending through said holes in said flange to connect the material on said opposite sides to form a mechanical bond between said seal element and said core, there being no adhesion or chemical bond between said core and said seal element, said mechanical bond being the only means for holding said seal element on said core.
Claim 3
Dependent Claim
13 words
A piston according to claim 1, wherein said core is molded from nylon.
Claim 4
Dependent Claim
21 words
A piston according to claim 1, wherein said core is molded from nylon fortified with other materials to enhance its strength.
Claim 5
Dependent Claim
18 words
A piston according to claim 3, wherein said other materials include glass fibers, silicone oil, and molybdinum disulfide.
Claim 6
Dependent Claim
14 words
A piston according to claim 1, wherein said seal element is molded from polyurethane.
Claim 7
Dependent Claim
17 words
A piston according to claim 1, wherein said seal element imbeds said flange on three sides thereof.
Claim 8
Independent Claim
166 words
A method of making a piston comprising the steps of: molding a core element from a rigid thermoplastic material, said core element consisting of a disc-shaped member having opposite sides and a radially extending flange at the perimeter thereof spaced axially inwardly from said sides, said flange having a plurality of holes extending therethrough; placing said core element in a mold without any adhesive or chemical bonding material on said core element; molding a seal element from a flexible thermoplastic material on said core element, on at least opposite sides of said flange and on said perimeter, the material of said seal element extending through said holes in said flange to connect the material on said opposite sides to form a mechanical bond between said seal element and said core element; and cooling said mold to prevent adhesion or chemical bonding of said seal element on said core element whereby said mechanical bond is the only means for holding said seal element on said core element.
Claim 9
Independent Claim
166 words
A method of making a piston comprising the steps of: molding a core element from a rigid thermoplastic material, said core element consisting of a disc-shaped member having opposite sides and a radially extending flange at the perimeter thereof spaced axially inwardly from said sides, said flange having a plurality of holes extending therethrough; placing said core element in a mold without any adhesive or chemical bonding material on said core element; molding a seal element from a flexible thermoplastic material on said core element, on at least opposite sides of said flange and on said perimeter, the material of said seal element extending through said holes in said flange to connect the material on said opposite sides to form a mechanical bond between said seal element and said core element; and cooling said mold to prevent adhesion or chemical bonding of said seal element on said core element whereby said mechanical bond is the only means for holding said seal element on said core element.
Claim 10
Dependent Claim
18 words
A method of making a piston according to claim 7, wherein said core element is molded from nylon.
Claim 11
Dependent Claim
26 words
A method of making a piston according to claim 7, wherein said core element is molded from nylon fortified with other materials to enhance its strength.
References Cited (Backward Citations)
US1746733A
Cited
US1797781A
Cited
US2295678A
Cited
US2309446A
Cited
US2793921A
Cited
US3176595A
Cited
US3181876A
Cited
US3179022A
Cited
US3319537A
Cited
US3802323A
Cited
US4066269A
Cited
US4034528A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-07-29 | 1984-01-28 | 1984-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-29 | 1988-01-28 | 1988-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-29 | 1992-01-28 | 1992-07-29 | $7700.00 | Window Closed / Lapsed |