US3633467A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic pump or motor device plungers
Assignee: Komatsu Ltd
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Filing: 1969-12-19
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Granted: 1972-01-11
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Expires: 1989-12-19
Abstract
Abstract A plunger for a pump or a motor comprising a plunger body having a hollow interior having a generally cylindrical inner surface and a filler body molded in the interior and prevented from axial, spiral and circumferential displacement relative to the plunger body by two portions of the inner surface differently shaped from each other and also from the generally cylindrical portions. The two portions may be two spiral grooves having different pitches from each other, or a groove having circumferentially varying depth. These grooves are radially deeper than the inner surface at the open end of the hollow interior.
Inventors
- 👤 Makoto Watanabe
- 👤 Naoyuki Kitayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:27
CPC Classifications
F; F16; F16J; F16J1/00; F16J1/005; F16J1/006; F04; F04B; F04B1/00; F04B1/12; F04B1/122; F04B1/124; F05; F05B; F05B2230/00; F05B2230/40; F05B2230/41; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49229; Y10T29/49236
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
258 words
A plunger for a pump or motor, comprising an elongated plunger body formed with a bore extending axially along the interior of said plunger body from one open end thereof and defined by an inner surface of said plunger body which is of a generally cylindrical configuration, a filler body situated within and filling said bore of said plunger body, said filler body having an outer surface which is complementary to and engages the entire area of the inner surface of said plunger body, said surfaces being formed respectively with complementary surface cavities and surface projections which respectively completely fill said cavities, an axial space defined between said one open end of said plunger body and said surface cavities and projections, said axial space having a radial dimension less than the radial dimension of the nearest complementary surface cavity and projection, whereby all said surface cavities and projections are situated inwardly of said one end of said plunger body up to which said filler body extends, so that all of said complementary surface cavities and projections are axially displaced away from said one end of said plunger body for preventing axial movement of said filler body out of said plunger body through said one end of the latter, each of said complementary surface cavities and projections extending at least through approximately 180* about the axis of said plunger body, and said plurality of complementary surface cavities and projections having a configuration which prevents axial, spiral, and circumferential movement of said filler body with respect to said plunger body.
Claim 2
Dependent Claim
258 words
A plunger for a pump or motor, comprising an elongated plunger body formed with a bore extending axially along the interior of said plunger body from one open end thereof and defined by an inner surface of said plunger body which is of a generally cylindrical configuration, a filler body situated within and filling said bore of said plunger body, said filler body having an outer surface which is complementary to and engages the entire area of the inner surface of said plunger body, said surfaces being formed respectively with complementary surface cavities and surface projections which respectively completely fill said cavities, an axial space defined between said one open end of said plunger body and said surface cavities and projections, said axial space having a radial dimension less than the radial dimension of the nearest complementary surface cavity and projection, whereby all said surface cavities and projections are situated inwardly of said one end of said plunger body up to which said filler body extends, so that all of said complementary surface cavities and projections are axially displaced away from said one end of said plunger body for preventing axial movement of said filler body out of said plunger body through said one end of the latter, each of said complementary surface cavities and projections extending at least through approximately 180* about the axis of said plunger body, and said plurality of complementary surface cavities and projections having a configuration which prevents axial, spiral, and circumferential movement of said filler body with respect to said plunger body.
Claim 3
Dependent Claim
22 words
The combination of claim 1 and wherein there are only two surface cavities and complementary surface projections respectively filling said surface cavities.
Claim 4
Dependent Claim
110 words
The combination of claim 2 and wherein said two complementary surface cavities and surface projections respectively filling said cavities are circumferentially displaced with respect to each other through 180* about the axis of said plunger body but are in axial alignment with respect to each other, with each of the surface cavities and the surface projections filling the latter having a configuration which provide each surface projection with a radial dimension with respect to the plunger body axis which gradually increases through approximately 90* and decreases through the remaining 90*, so that the pair of complementary surface cavities and projections form in cross section an area of substantially elliptical configuration.
Claim 5
Dependent Claim
45 words
The combination of claim 1 and wherein said complementary surface projections and cavities are in the form of screw threads which respectively differ from each other so that turning at one of the screw threads will result in binding at another of the screw threads.
Claim 6
Dependent Claim
33 words
The combination of claim 4 and wherein said screw threads which form the complementary surface cavities and projections are axially displaced with respect to each other along the axis of said plunger body.
Claim 7
Dependent Claim
27 words
The combination of claim 5 and wherein there are only two screw threads forming a pair of surface cavities and complementary surface projections filling the surfacE cavities.
Claim 8
Dependent Claim
55 words
The combination of claim 6 and wherein said two screw threads are located one nearer to said one end of said plunger body than the other, and that one of said screw threads which is nearer to said one end of said plunger body having a diameter greater than the other of the screw threads.
Claim 9
Dependent Claim
20 words
The combination of claim 6 and wherein said two screw threads are respectively a left-hand thread and a right-hand thread.
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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |