US3847377A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Safety lowering device
Assignee: Safety Devices Inc
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Filing: 1973-06-07
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Granted: 1974-11-12
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Expires: 1993-06-07
Abstract
Abstract A safety device utilizing a drum and cable arrangement for lowering a person or load at a substantially constant speed. A plurality of radially displaceable vanes or blades rotate with the drum and are positioned within a fluid-filled, sealed housing. A fixed plate is secured within the housing to depress the vanes upon movement past the plate to control rotation of the drum.
Inventors
- 👤 C Byrd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:12
CPC Classifications
B; B66; B66D; B66D5/00; B66D5/02; B66D5/026; A; A62; A62B; A62B1/00; A62B1/06; A62B1/08; A62B1/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
120 words
Apparatus for controlling the rate of descent of a load comprising, a rotatable shaft, a drum mounted upon said shaft for rotation therewith to wind or pay out a line attached to the drum, support means, a fluid-filled, sealed housing assembly mounted upon said support means, said housing assembly rotatably supporting said shaft, rotor means, including a plurality of vanes, attached to said shaft for rotation therewith and vane engaging cam means projecting within a segment of less than 90* within said housing assembly for displacing said vanes relative to said roTor means upon rotation thereof whereby said vanes are projected radially substantially the same extent during rotation of said rotor means until engagement with said vane engaging cam means.
Claim 2
Dependent Claim
120 words
Apparatus for controlling the rate of descent of a load comprising, a rotatable shaft, a drum mounted upon said shaft for rotation therewith to wind or pay out a line attached to the drum, support means, a fluid-filled, sealed housing assembly mounted upon said support means, said housing assembly rotatably supporting said shaft, rotor means, including a plurality of vanes, attached to said shaft for rotation therewith and vane engaging cam means projecting within a segment of less than 90* within said housing assembly for displacing said vanes relative to said roTor means upon rotation thereof whereby said vanes are projected radially substantially the same extent during rotation of said rotor means until engagement with said vane engaging cam means.
Claim 3
Dependent Claim
47 words
Apparatus as recited in claim 1, wherein said two drums, each having a line attached thereto, are secured to said shaft for rotation therewith, one line being unwound from one drum and a second line being wound upon the other drum upon rotation of the rotor means.
Claim 4
Dependent Claim
36 words
Apparatus as recited in claim 2, said rotor means including a rotor member mounted for rotation with said shaft, said member defining a plurality of radially directed slots, said vanes being slidably mounted within said slots.
Claim 5
Dependent Claim
21 words
Apparatus as recited in claim 3, and further including means biasing said vanes radially outwardly into engagement with said housing assembly.
Claim 6
Dependent Claim
30 words
Apparatus as recited in claim 4, said means within said housing assembly including a plate having a face for radially displacing inwardly said vanes as they rotate passed said plate.
Claim 7
Dependent Claim
27 words
Apparatus as recited in claim 5, wherein each vane defines an opening to permit fluid to flow from one side of the vane to the other side.
Claim 8
Dependent Claim
40 words
Apparatus as recited in claim 6, wherein the width of said vanes correspond substantially to the internal width of said housing assembly and said vanes normally extend from said rotor member outwardly into frictional, sliding engagement with said housing assembly.
Claim 9
Dependent Claim
36 words
Apparatus as recited in claim 1, said rotor means including a rotor member mounted for rotation with said shaft, said member defining a plurality of radially directed slots, said vanes being slidably mounted within said slots.
Claim 10
Dependent Claim
49 words
Apparatus as recited in claim 8, said means within said housing assembly including a plate having a face for radially displacing inwardly said vanes as they rotate passed said plate, each vane defining an opening to permit fluid to flow from one side of the vane to the other.
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) | 1977-11-11 | 1978-05-13 | 1978-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-11 | 1982-05-13 | 1982-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-11 | 1986-05-13 | 1986-11-12 | $7700.00 | Window Closed / Lapsed |