US4624224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic valve lifter
Assignee: Aisin Corp
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Filing: 1984-08-24
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Granted: 1986-11-25
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Expires: 2004-08-24
Abstract
Abstract A hydraulic valve lifter is mounted in a rocker arm of a valve train assembly of internal combustion engines. The lifter includes a cylinder formed in the rocker arm, a plunger reciprocably mounted in the cylinder, a seat member securely pressed in the cylinder above the plunger and provided with an outer circumferential portion extending in a direction of the plunger, a stopper surface formed at an end surface of the outer circumferential portion for restricting an axial movement of the plunger in a direction of the seat member, and a relief recessed area formed above the stopper surface for finishing machining process of the cylinder.
Inventors
- 👤 Hisashi Kodama
- 👤 Takuro Ono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:28
CPC Classifications
F; F01; F01L; F01L1/00; F01L1/20; F01L1/22; F01L1/24; F01L1/2411
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
188 words
A hydraulic valve lifter mounted in a rocker arm of a valve train assembly of internal combustion engines, said lifter comprising: a cylinder having a cylindrical surface formed in said rocker arm; a plunger reciprocably mounted in said cylinder in sliding contact with said cylindrical surface; a seat member securely pressed in said cylinder above said plunger, said seat member defining a reservoir chamber and a pressure chamber in said cylinder and having an outer circumferential portion extending in contact with said cylindrical surface in a direction of said plunger; a stopper means formed at an end surface of said outer circumferential portion of said seat member for restricting an axial movement of said plunger in a direction of said seat member; and at least one relief recess means formed in said cylindrical surface above said stopper means for a finishing machining process of said cylinder whereby each recess means is completely covered by said outer circumferential portion of said seat member such that said cylindrical surface encircles said plunger and is formed by an uninterupted smooth sliding surface along the entire length of movement of said plunger.
Claim 2
Dependent Claim
188 words
A hydraulic valve lifter mounted in a rocker arm of a valve train assembly of internal combustion engines, said lifter comprising: a cylinder having a cylindrical surface formed in said rocker arm; a plunger reciprocably mounted in said cylinder in sliding contact with said cylindrical surface; a seat member securely pressed in said cylinder above said plunger, said seat member defining a reservoir chamber and a pressure chamber in said cylinder and having an outer circumferential portion extending in contact with said cylindrical surface in a direction of said plunger; a stopper means formed at an end surface of said outer circumferential portion of said seat member for restricting an axial movement of said plunger in a direction of said seat member; and at least one relief recess means formed in said cylindrical surface above said stopper means for a finishing machining process of said cylinder whereby each recess means is completely covered by said outer circumferential portion of said seat member such that said cylindrical surface encircles said plunger and is formed by an uninterupted smooth sliding surface along the entire length of movement of said plunger.
Claim 3
Dependent Claim
22 words
A hydraulic valve lifter according to claim 1 wherein said seat member is made of a material having a high wear resistance.
Claim 4
Dependent Claim
31 words
A hydraulic valve lifter according to claim 1 wherein said seat member is provided with a coaxial passageway establishing a hydraulic fluid communication between said reservoir chamber and said pressure chamber.
Claim 5
Dependent Claim
32 words
A hydraulic valve lifter according to claim 3 additionally including a check valve located in said coaxial passageway for permitting a hydraulic fluid flow from said reservoir chamber to said pressure chamber.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-24 | 1990-05-26 | 1990-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-24 | 1994-05-26 | 1994-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-24 | 1998-05-26 | 1998-11-25 | $7700.00 | Window Closed / Lapsed |