US3584838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Roof hoists
Assignee: ELECTROHOISTS PATENTS Ltd
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Filing: 1969-02-17
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Granted: 1971-06-15
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Expires: 1989-02-17
Abstract
Abstract A portable hoist capable of being moved from location to location with but little dismantling and comprising a simple frame with two cable drums geared together, two electric motors allocated respectively to the cable drums for winding and unwinding the cables, and two brake mechanisms, one for each cable drum, arranged automatically to stop the drums when the power supply to the motors is interrupted. There are two detachable jibs for carrying the cables over, for example, the edge of a tall building. There is also a portable control box arranged to be connected to any convenient source of electrical power and containing the switchgear necessary for the motors and brake mechanisms. Remote control may be effected by an electrical controller manually actuable in a cradle supported by the hoist. The hoist may be divided into two units, each with one drum, one motor, one brake mechanism and one jib.
Inventors
- 👤 Herbert C Tampin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:15
CPC Classifications
B; B66; B66D; B66D1/00; B66D1/26; B66D2700/00; B66D2700/01; B66D2700/0125; B66D2700/0166
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
266 words
A portable hoist, comprising: a frame, two vertical parallel cable drum spindles rotatably mounted on said frame, a cable drum axially slidably and nonrotatably mounted on each said drum spindle for rotation therewith about the axis of its respective spindle, bearings rotatably supporting each spindle on the frame, each said bearing being located below its respective cable drum, two intermeshing gears nonrotatably mounted one on each of said spindles for rotation therewith, each of said intermeshing gears located beneath its respective cable drum, such that the spindles and hence the drums, are caused to rotate in opposite directions at the same speed, two electric motors mounted on the frame, one of said electric motors being drivingly engaged with each of said intermeshing gears for driving the cable drums, two brake mechanisms mounted one on each of said spindles for braking its respective spindle, and hence for braking the cable drum on that spindle, each of said brake mechanisms located beneath the cable drum on its respective spindle, electrical means for maintaining said brake mechanisms in their brake releasing positions, and means for manually applying both of said brake mechanisms simultaneously to hold their respective spindles against rotation, the portion of the spindles above the cable drums thus being substantially free of obstructions so that the cable drums can be removed upwardly off of their respective spindles without disturbing said gears, said bearings or said brakes, whereby portability of the hoist is provided by substantially reducing its overall weight by removing the wound cable drums from the frame without the necessity for significant dismantling of the hoist.
Claim 2
Dependent Claim
266 words
A portable hoist, comprising: a frame, two vertical parallel cable drum spindles rotatably mounted on said frame, a cable drum axially slidably and nonrotatably mounted on each said drum spindle for rotation therewith about the axis of its respective spindle, bearings rotatably supporting each spindle on the frame, each said bearing being located below its respective cable drum, two intermeshing gears nonrotatably mounted one on each of said spindles for rotation therewith, each of said intermeshing gears located beneath its respective cable drum, such that the spindles and hence the drums, are caused to rotate in opposite directions at the same speed, two electric motors mounted on the frame, one of said electric motors being drivingly engaged with each of said intermeshing gears for driving the cable drums, two brake mechanisms mounted one on each of said spindles for braking its respective spindle, and hence for braking the cable drum on that spindle, each of said brake mechanisms located beneath the cable drum on its respective spindle, electrical means for maintaining said brake mechanisms in their brake releasing positions, and means for manually applying both of said brake mechanisms simultaneously to hold their respective spindles against rotation, the portion of the spindles above the cable drums thus being substantially free of obstructions so that the cable drums can be removed upwardly off of their respective spindles without disturbing said gears, said bearings or said brakes, whereby portability of the hoist is provided by substantially reducing its overall weight by removing the wound cable drums from the frame without the necessity for significant dismantling of the hoist.
Claim 3
Dependent Claim
33 words
A portable hoist according to claim 1, including two detachable jibs removably connected to said frame, said jibs having sheaves mounted at their outer end over which the cables from said drums travel.
Claim 4
Dependent Claim
31 words
A portable hoist according to claim 2, wherein each said jib is formed in at least two sections divisible from each other and assembled end to end in the completed jib.
Claim 5
Dependent Claim
27 words
A portable hoist according to claim 2, including means for pivotably mounting each jib on the frame to enable the separation between the sheaves to be adjusted.
Claim 6
Dependent Claim
50 words
A portable hoist according to claim 1, including a portable electrical control box containing means for controlling said motors and said electrical brake-maintaining means and having a connection for connection to a source of electrical power, a connection to said motors, and a connection to a remote manually operable controller.
Claim 7
Dependent Claim
35 words
A portable hoist according to claim 1, wherein each brake mechanism includes caliper brake shoes arranged to be applied to brake drums under the action of springs and wherein said electrical means comprises electrical magnets.
Claim 8
Dependent Claim
34 words
A portable hoist according to claim 1, wherein at least one of the motors is furnished with a hand-operated brake on its shaft and includes means including a handle for turning its shaft manually.
Claim 9
Dependent Claim
46 words
A portable hoist according to claim 1, wherein the frame is divisible into two parts, each constituting a self-contained hoist or winch including one of the drums, one of the motors, one of the brake mechanisms and electrical and mechanical means for controlling the brake mechanisms.
Claim 10
Dependent Claim
38 words
A portable hoist according to claim 1, wherein, on each spindle, the said gear is located immediately beneath the cable drum, the brake mechanism is located immediately beneath the gear, and the bearing is located beneath the brake.
Claim 11
Dependent Claim
71 words
A portable hoist according to claim 1, including jibs connected to said frame and having sheaves mounted at their outer ends over which the cables from said drums travel, and wherein the jibs extend generally horizontally outwardly from the frame, wherein the frame, beneath the cable drum and the jibs can rest on a generally horizontal surface with the outer ends of the jibs projecting beyond the edge of such surface.
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) | 1974-06-14 | 1974-12-14 | 1975-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-14 | 1978-12-14 | 1979-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-14 | 1982-12-14 | 1983-06-15 | $7700.00 | Window Closed / Lapsed |