US4012909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hammer
Assignee: FM Industries Inc
•
Filing: 1975-11-28
•
Granted: 1977-03-22
•
Expires: 1995-11-28
Abstract
Abstract A hammer and more particularly a fluid operable hammer wherein alternating impetus provided by pressurized liquid and gas means actuates a reciprocable hammer piston to generate repetitive impact loads.
Inventors
- 👤 George A. Hibbard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:01
CPC Classifications
B; B25; B25D; B25D9/00; B25D9/06; B25D9/12; F; F01; F01L; F01L17/00; F01L25/00; F01L25/02; F01L25/04
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
167 words
A fluid operative impacting assembly comprising: an elongated body member having a bore extending longitudinally therein; hammer piston axially movable within said bore to form two axially spaced variable volume chambers therein; an exhaust chamber carried by said body member; valved passageway means in said body member to control fluid communication between one of said variable volume chambers and said exhaust chamber; said one of said variable volume chambers and said exhaust chamber being adapted to receive hydraulic fluid therein; said exhaust chamber having a volume greater than the maximum volume of said one of said variable volume chambers; and pump means communicating with said exhaust chamber for removing hydraulic fluid from said exhaust chamber during said axial movement of said hammer piston at a rate sufficient to allow discharge of hydraulic fluid from said one of said variable volume chambers into said exhaust chamber while maintaining minimum back pressure therein when said one of said variable volume chambers in in fluid communication with said exhaust chamber.
Claim 2
Dependent Claim
167 words
A fluid operative impacting assembly comprising: an elongated body member having a bore extending longitudinally therein; hammer piston axially movable within said bore to form two axially spaced variable volume chambers therein; an exhaust chamber carried by said body member; valved passageway means in said body member to control fluid communication between one of said variable volume chambers and said exhaust chamber; said one of said variable volume chambers and said exhaust chamber being adapted to receive hydraulic fluid therein; said exhaust chamber having a volume greater than the maximum volume of said one of said variable volume chambers; and pump means communicating with said exhaust chamber for removing hydraulic fluid from said exhaust chamber during said axial movement of said hammer piston at a rate sufficient to allow discharge of hydraulic fluid from said one of said variable volume chambers into said exhaust chamber while maintaining minimum back pressure therein when said one of said variable volume chambers in in fluid communication with said exhaust chamber.
Claim 3
Dependent Claim
25 words
A fluid operative impacting assembly as specified in claim 1 wherein said pump means includes a suction pump in fluid communication with said exhaust chamber.
Claim 4
Dependent Claim
50 words
A fluid operative impacting assembly as specified in claim 1 additionally comprising check valve means between said exhaust chamber and the exterior thereof for permitting the entrance of ambient air into said exhaust chamber in response to the removal of hydraulic fluid from said exhaust chamber by said pump means.
Claim 5
Dependent Claim
35 words
A fluid operative impacting assembly as specified in claim 1 wherein the volume of said exhaust chamber is at least twice as great as the maximum volume of said one of said variable volume chambers.
Claim 6
Dependent Claim
54 words
A fluid operative impacting assembly as specified in claim 1 wherein said pump means removes hydraulic fluid from said exhaust chamber at a rate sufficient to remove a volume of hydraulic fluid at least equal to the maximum volume of said one of said variable volume chambers per impact stroke of said hammer piston.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-21 | 1980-09-20 | 1981-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-21 | 1984-09-20 | 1985-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-21 | 1988-09-20 | 1989-03-22 | $7700.00 | Window Closed / Lapsed |