US3782483A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Percussion hammer
Assignee: Vulcan Iron Works Inc
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Filing: 1971-11-15
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Granted: 1974-01-01
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Expires: 1991-11-15
Abstract
Abstract There is provided a percussion hammer of the type used for driving piles and the like, and including a differential diameter piston defining a ram reciprocally positioned within a differential diameter cylinder. An anvil is mounted for limited movement in one end of the cylinder positioned in the path of the ram to receive percussion blows therefrom. Main valve means are provided for controlling the working fluid so as to cycle the ram through power and return strokes. Safety means are provided for shutting off the supply of working fluid rendering the ram inoperative when the percussion hammer is out of engagement with a pile.
Inventors
- 👤 G Wandell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:37
CPC Classifications
E; E02; E02D; E02D7/00; E02D7/02; E02D7/06; E02D7/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A percussion hammer adapted to rest on a pile and comprising a housing having defined therein a cylinder; a piston mounted in said cylinder and defining a ram; an impact anvil mounted for limited movement in one end of said cylinder positioned in the path of said ram, said anvil being supported in an upper position when the hammer rests on a pile and dropping to a lower position when the hammer is out of engagement with a pile; main valve means for controlling the working fluid to cycle said ram through power and return strokes; and safety means including safety valve means for closing off the supply of working fluid and directly actuated by said piston when said piston drops to said lower position.
Claim 2
Dependent Claim
125 words
A percussion hammer adapted to rest on a pile and comprising a housing having defined therein a cylinder; a piston mounted in said cylinder and defining a ram; an impact anvil mounted for limited movement in one end of said cylinder positioned in the path of said ram, said anvil being supported in an upper position when the hammer rests on a pile and dropping to a lower position when the hammer is out of engagement with a pile; main valve means for controlling the working fluid to cycle said ram through power and return strokes; and safety means including safety valve means for closing off the supply of working fluid and directly actuated by said piston when said piston drops to said lower position.
Claim 3
Dependent Claim
240 words
A percussion hammer adapted to rest on a pile and comprising a housing having defined therein a cylinder; a piston mounted in said cylinder and defining a ram; an impact anvil mounted for limited movement in one end of said cylinder positioned in the path of said ram, said anvil being supported in an upper position when the hammer rests on a pile and dropping to a lower position when the hammer is out of engagement with a pile; said piston having a working stroke between an upper position in which said ram is raised above said impact anvil, and an intermediate position wherein said ram strikes said impact anvil when said hammer rests on a pile so that said anvil is in its upper position, and a lower position wherein said ram rests on said impact anvil when said hammer is out of engagement with a pile so that said anvil is in its lower position; main valve means for controlling the working fluid to cycle said ram through power and return strokes; said piston having a safety cam operatively associated therewith and safety means including safety valve means closing off the supply of working fluid to said main valve when said impact anvil is out of engagement with a pile; said safety valve including a cam follower element engageable with said safety cam when said ram is in said lower position to close off the supply of fluid.
Claim 4
Dependent Claim
240 words
A percussion hammer adapted to rest on a pile and comprising a housing having defined therein a cylinder; a piston mounted in said cylinder and defining a ram; an impact anvil mounted for limited movement in one end of said cylinder positioned in the path of said ram, said anvil being supported in an upper position when the hammer rests on a pile and dropping to a lower position when the hammer is out of engagement with a pile; said piston having a working stroke between an upper position in which said ram is raised above said impact anvil, and an intermediate position wherein said ram strikes said impact anvil when said hammer rests on a pile so that said anvil is in its upper position, and a lower position wherein said ram rests on said impact anvil when said hammer is out of engagement with a pile so that said anvil is in its lower position; main valve means for controlling the working fluid to cycle said ram through power and return strokes; said piston having a safety cam operatively associated therewith and safety means including safety valve means closing off the supply of working fluid to said main valve when said impact anvil is out of engagement with a pile; said safety valve including a cam follower element engageable with said safety cam when said ram is in said lower position to close off the supply of fluid.
Claim 5
Dependent Claim
266 words
A double acting percussion hammer adapted to rest on a pile and comprising a housing having defined therein a differential diameter cylinder closed at its larger end; a piston of corresponding different diameters mounted in said cylinder and defining a ram; said piston including a safety cam defined in its surface; an impact anvil mounted for limited movement in one end of said cylinder positioned in the path of said ram, said anvil being supported in an upper position when the hammer rests on a pile and dropping to a lower position when the hammer is out of engagement with a pile; safety valve means for controlling the inlet of working fluid into the space in said cylinder between the differential diameters of said cylinder; passage means interconnecting said space and the closed end of said cylinder; main valve means in said passage means sequentially connecting said closed end with said space and with exhaust to cycle said ram through power and return strokes between an upper piston position in which said ram is raised above said impact anvil and an intermediate piston position wherein said ram sTrikes said impact anvil when said hammer rests on a pile so that said anvil is in its upper position, said ram moving to a lower piston position when said hammer is out of engagement with a pile so that said anvil is in its lower position; said safety valve including a cam follower element engageable with said safety cam when said ram is in said lower piston position to close off the supply of fluid into said space.
Claim 6
Dependent Claim
266 words
A double acting percussion hammer adapted to rest on a pile and comprising a housing having defined therein a differential diameter cylinder closed at its larger end; a piston of corresponding different diameters mounted in said cylinder and defining a ram; said piston including a safety cam defined in its surface; an impact anvil mounted for limited movement in one end of said cylinder positioned in the path of said ram, said anvil being supported in an upper position when the hammer rests on a pile and dropping to a lower position when the hammer is out of engagement with a pile; safety valve means for controlling the inlet of working fluid into the space in said cylinder between the differential diameters of said cylinder; passage means interconnecting said space and the closed end of said cylinder; main valve means in said passage means sequentially connecting said closed end with said space and with exhaust to cycle said ram through power and return strokes between an upper piston position in which said ram is raised above said impact anvil and an intermediate piston position wherein said ram sTrikes said impact anvil when said hammer rests on a pile so that said anvil is in its upper position, said ram moving to a lower piston position when said hammer is out of engagement with a pile so that said anvil is in its lower position; said safety valve including a cam follower element engageable with said safety cam when said ram is in said lower piston position to close off the supply of fluid into said space.
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) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |