Patent US3777879A successfully refreshed from Google Patents.
US3777879A
Expired / Lapsed
US
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Control for a conveyor take-up
Assignee: WEBB CO J
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Filing: 1971-11-30
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Granted: 1973-12-11
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Expires: 1991-11-30
Abstract
Abstract Relative movement between the fixed and movable frames of a conveyor take-up is controlled by a hydraulic cylinder and piston unit, the cylinder of which is connected to one of the frames and the piston to the other, the movable take-up frame being normally urged in an extending direction to apply tension to the conveyor chain. The hydraulic cylinder is connected to a fluid passage containing an orifice which permits fluid flow at a controlled rate in response to extending movement of the take-up, and containing a check valve which obstructs fluid flow in the opposite direction and prevents collapsing movement of the takeup. A normally open solenoid valve in this passage is operable to obstruct flow in both directions in the event the conveyor drive shuts down. A pressure relief valve mounted in an alternate passage permits collapsing take-up movement in the event of abnormal tension in the conveyor chain. In one embodiment, the hydraulic cylinder is combined with an air cylinder, and the pistons of both cylinders are mounted on a common rod, the air cylinder being supplied with regulated air pressure to apply a normal extending force to the movable take-up frame.
Inventors
- 👤 C Dehne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:59
CPC Classifications
B; B65; B65G; B65G23/00; B65G23/44
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
206 words
A control for a take-up of a conveyor having an endless chain driven by a driving unit, the take-up including a fixed frame, a moveable frame carried thereby and supporting the endless chain, and means normally urging the moveable frame in an extending direction such as to apply tension to the endless chain, wherein the improvement comprises: means for regulating the movement of the moveable frame including, a hydraulic unit having a cylinder member and a piston member dividing the cylinder member into two chambers, one of the cylinder and piston members being connected to the fixed frame of the take-up and the other of said members being connected to and moveable with the moveable frame of the take-up, fluid flow passages communicating with each of said chambers, and flow control means connected to at least one of said passages for permitting fluid flow therethrough at a controlled rate in one direction and a normally open valve for obstructing such fluid flow in said one direction in response to a nondriving condition of the conveyor driving unit, said one direction of fluid flow allowing relative movement between the cylinder and piston members occasioned by normally urged movement of the moveable take-up frame in the extending direction.
Claim 2
Dependent Claim
206 words
A control for a take-up of a conveyor having an endless chain driven by a driving unit, the take-up including a fixed frame, a moveable frame carried thereby and supporting the endless chain, and means normally urging the moveable frame in an extending direction such as to apply tension to the endless chain, wherein the improvement comprises: means for regulating the movement of the moveable frame including, a hydraulic unit having a cylinder member and a piston member dividing the cylinder member into two chambers, one of the cylinder and piston members being connected to the fixed frame of the take-up and the other of said members being connected to and moveable with the moveable frame of the take-up, fluid flow passages communicating with each of said chambers, and flow control means connected to at least one of said passages for permitting fluid flow therethrough at a controlled rate in one direction and a normally open valve for obstructing such fluid flow in said one direction in response to a nondriving condition of the conveyor driving unit, said one direction of fluid flow allowing relative movement between the cylinder and piston members occasioned by normally urged movement of the moveable take-up frame in the extending direction.
Claim 3
Dependent Claim
45 words
A control according to claim 1 wherein the flow control means includes an orifice and a check valve in series, said normally open valve is in series with said orifice and check valve, said normally open valve being electrically interlocked with the conveyor driving unit.
Claim 4
Dependent Claim
35 words
A control according to claim 1 wherein said regulating means includes a manually operable valve connected in parallel with the flow control means, said manually operable valve permitting fluid flow in both directions when open.
Claim 5
Dependent Claim
60 words
A control according to claim 1 wherein said regulating means includes a pressure relief valve connected in parallel with the flow control means, said pressure relief valve being capable of permitting flow in response to a hydraulic pressure build-up in excess of a preset valve resulting from force on the moveable taKe-up frame in the direction of collapsing movement thereof.
Claim 6
Dependent Claim
46 words
A control according to claim 1 wherein the means normally urging the movable frame in an extending direction includes a hydraulic fluid reser-voir, means for applying pressure to hydraulic fluid contained therein, said pressure forcing hydraulic fluid through the flow control means in said one direction.
Claim 7
Dependent Claim
96 words
A control according to claim 1 wherein the means normally urging the movable frame in an extending direction includes a second fluid pressure cylinder member connected to the cylinder member of said hydraulic unit in end-to-end relation, a rod extending through the cylinder member of the hy-draulic unit and into the second fluid pressure cylinder member, a second piston secured to the rod within the second fluid pressure cylinder member, and means for applying fluid pressure to one side of the second piston for nor-mally urging the movable frame of the take-up in the extending direction.
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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) | 1976-12-10 | 1977-06-11 | 1977-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-10 | 1981-06-11 | 1981-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-10 | 1985-06-11 | 1985-12-11 | $7700.00 | Window Closed / Lapsed |