US3589504A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Torque limiting means for conveyors
Assignee: Fairfield Engineering and Manufacturing Co
•
Filing: 1969-01-31
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Granted: 1971-06-29
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Expires: 1989-01-31
Abstract
Abstract A chain conveyor operating in a conveyor housing is driven by a rotatably mounted drive motor to exert a counter rotational reaction torque against a resilient stop element. When the reaction torque exceeds a preselected value, compression of the stop element trips a motor cutoff switch to stop the conveyor, which remains stopped until the switch is manually reset.
Inventors
- 👤 Ronald S Blough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:28
CPC Classifications
A; A01; A01K; A01K5/00; A01K5/02; A01K5/0208; B; B65; B65G; B65G23/00; B65G2811/00; B65G2811/09; B65G2811/091; B65G2811/093
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
153 words
An overload protection system for a conveyor having a chain slidably supported within a conveyor housing, comprising in combination: a drive sprocket substantially vertically journaled on said conveyor housing in driving engagement with said chain; a drive motor having a substantially vertical output shaft coupled to said sprocket, said motor being supported by said sprocket and rotatable relative to said housing; means for resiliently resisting said motor rotation caused by reaction torque resulting from said motor driving said sprocket and chain in a forward direction, said means being operably connected to said motor and contacting said housing; a motor cutoff switch mounted on said motor; linkage means for actuating said cutoff switch responsive to deflection of the resilient resisting means exceeding a predetermined value, said linkage means being carried by said motor and contacting said housing; and automatic switching means connected in series with the motor cutoff switch for periodically energizing said motor.
Claim 2
Dependent Claim
153 words
An overload protection system for a conveyor having a chain slidably supported within a conveyor housing, comprising in combination: a drive sprocket substantially vertically journaled on said conveyor housing in driving engagement with said chain; a drive motor having a substantially vertical output shaft coupled to said sprocket, said motor being supported by said sprocket and rotatable relative to said housing; means for resiliently resisting said motor rotation caused by reaction torque resulting from said motor driving said sprocket and chain in a forward direction, said means being operably connected to said motor and contacting said housing; a motor cutoff switch mounted on said motor; linkage means for actuating said cutoff switch responsive to deflection of the resilient resisting means exceeding a predetermined value, said linkage means being carried by said motor and contacting said housing; and automatic switching means connected in series with the motor cutoff switch for periodically energizing said motor.
Claim 3
Dependent Claim
60 words
Apparatus as defined in claim 1 in which said biasing means includes a preloaded compression spring interposed between a nut and a collar on a threaded plunger, means for preventing rotation of the nut as the plunger is turned to vary the amount of spring preload, and indicator means for furnishing a visual indication of the amount of spring preload.
Claim 4
Dependent Claim
76 words
Apparatus as defined in claim 1 in which said linkage means includes a manually operable switch actuating member engageable with said drive motor and conveyor housing for shifting movement in one direction to automatically actuate said cutoff switch in response to drive motor reaction torque greater than said preselected value, and which is unrestrained for shifting movement in the opposite direction upon the removal of said torque to allow said cutoff switch to be manually reset.
Claim 5
Dependent Claim
18 words
Apparatus as defined in claim 1 including a remote warning lamp connected in parallel across said cutoff switch.
Claim 6
Dependent Claim
35 words
Apparatus as defined in claim 1 wherein said drive sprocket is journaled on an element forming a corner of the conveyor housing and the chain is pulled and guided around the corner by the sprocket.
Claim 7
Dependent Claim
22 words
Apparatus as defined in claim 5 wherein said drive motor is journaled for rotation on said corner element above said drive sprocket.
Claim 8
Dependent Claim
22 words
Apparatus as defined in claim 1 wherein said automatic switching means includes an electric timeclock for energizing the motor at predetermined intervals.
Claim 9
Dependent Claim
23 words
Apparatus as defined in claim 1 wherein said automatic switching means includes a bin level switch connected in series with the cutoff switch.
References Cited (Backward Citations)
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US2387047A
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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) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |