Patent US3978772A successfully refreshed from Google Patents.
US3978772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piston shoe for fluid pressure pump motor
Assignee: Aisin Corp
•
Filing: 1974-02-19
•
Granted: 1976-09-07
•
Expires: 1994-02-19
Abstract
Abstract A piston shoe for fluid pressure pump motors of the piston type is substantially disc-shaped and includes a concave portion provided upon one end face thereof for seating the convex portion of a piston rod associated with the piston and cylinder assemblies of the pump motor, while the other end face thereof is substantially flat for contacting the sliding surface of a swash plate. A holder or retainer is also provided in association with the shoe for retaining the piston rod within the concave seat, such retainer being secured to the shoe by biasing means, or alternatively by being pressed or crimped thereon.
Inventors
- 👤 Takayuki Miyao
- 👤 Hiroaki Maeda
- 👤 Masanori Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:46
CPC Classifications
F; F04; F04B; F04B1/00; F04B1/12; F04B1/20; F04B1/122; F04B1/124; F04B1/2014; F04B1/2035
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
160 words
A piston shoe for fluid pressure pump motors of the piston type, comprising: a substantially flat, plate-type shoe having a concave portion, for seating a convex portion of a piston rod, defined within one end surface therof and a substantially planar portion for contacting a sliding surface of a swash plate at the other end thereof; a malleable holder capable of being worked so as to have a configuration corresponding to that of said convex portion of said piston and thereby support, and be caulked to, said convex portion of said piston rod at one end thereof, said holder being separate from, yet capable of being worked so as to have a configuration corresponding to that of said shoe and thereby be relatively immovably held in contacting relation with said shoe at the other end thereof; and discharging means defined within said shoe for discharging the hydraulic fluid within a chamber defined by said shoe, said holder, and said piston.
Claim 2
Dependent Claim
160 words
A piston shoe for fluid pressure pump motors of the piston type, comprising: a substantially flat, plate-type shoe having a concave portion, for seating a convex portion of a piston rod, defined within one end surface therof and a substantially planar portion for contacting a sliding surface of a swash plate at the other end thereof; a malleable holder capable of being worked so as to have a configuration corresponding to that of said convex portion of said piston and thereby support, and be caulked to, said convex portion of said piston rod at one end thereof, said holder being separate from, yet capable of being worked so as to have a configuration corresponding to that of said shoe and thereby be relatively immovably held in contacting relation with said shoe at the other end thereof; and discharging means defined within said shoe for discharging the hydraulic fluid within a chamber defined by said shoe, said holder, and said piston.
Claim 3
Dependent Claim
53 words
A piston shoe for fluid pressure pump motors of the piston type as set forth in claim 1 wherein said holder is relatively immovably held in contacting relation with said shoe by a biasing means operatively connected with said holder and supporting said shoe and said piston rod through means of said holder.
Claim 4
Dependent Claim
24 words
A piston shoe for fluid pump motors of the piston type as set forth in claim 1 wherein said discharging means is a groove.
Claim 5
Dependent Claim
43 words
A piston shoe for fluid pressure pump motors of the piston type as set forth in claim 1, wherein said other end of said holder is caulked to said shoe for holding said holder in relative immovable and contacting relation with said shoe.
Claim 6
Dependent Claim
35 words
A piston shoe for fluid pressure pump motors of the piston type as set forth in claim 1, wherein said other end of said holder is crimped so as to be connected to said shoe.
Claim 7
Dependent Claim
36 words
A piston shoe for fluid pressure pump motors of the piston type as set forth in claim 1, wherein said other end of said holder is pressed into said shoe so as to be connected thereto.
References Cited (Backward Citations)
SU242606A1
Cited
US2674196A
Cited
US2638850A
Cited
US2880042A
Cited
US3283725A
Cited
US3726189A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-07 | 1980-03-08 | 1980-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-07 | 1984-03-08 | 1984-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-07 | 1988-03-08 | 1988-09-07 | $7700.00 | Window Closed / Lapsed |