Patent US3729696A successfully refreshed from Google Patents.
US3729696A
Expired / Lapsed
US
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Time delay actuator
Assignee: Heinemann Electric Co
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Filing: 1972-04-26
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Granted: 1973-04-24
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Expires: 1992-04-26
Abstract
Abstract A hydraulic-magnetic time delay actuator for use with circuit breakers, switches or relays, comprising a non-magnetic time delay tube encircled by a solenoid coil. The tube contains a retarding fluid and a magnetic core, the core being movable longitudinally in the tube in response to the magnetic flux generated by the coil. An armature is pivotally located in the magnetic field of the coil and is movable thereby to actuate the relay, circuit breaker or switch. The movable core has formed therethrough an axial bore which houses a valve and forms a seat for the valve adjacent one end of the bore. A helical stop spring, a portion of which has an outer diameter greater than the interior diameter of the bore, is located therein. The stop spring is inserted into the bore by twisting the spring to reduce its diameter while concurrently pushing it into the bore. The spring is held in place in the bore by frictional engagement with the interior surface thereof. The leading edge of the inserted stop spring is located a preselected distance from the valve seat to limit the movement of the valve away from its seat. The stop spring is tapered slightly in the direction of the valve and is formed of a magnetically permeable material in order to increase the efficiency of the actuator.
Inventors
- 👤 R Pope
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:19
CPC Classifications
H; H01; H01H; H01H71/00; H01H71/10; H01H71/12; H01H71/24; H01H71/34; H01H71/345
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
163 words
A time delay actuator comprising, a magnetic frame, a tube supported from the frame, a coil encircling said tube, a pole piece forming a closure for one end of said tube, an armature pivotally supported from said frame and rotatable toward and away from said pole piece, a fluid filling said tube, a magnetically permeable core in said tube, said core being movable along the axis of said tube through said fluid under the influence of the magnetic flux generated by said coil, said core including an axial bore therethrough, a ball valve located in said bore, said bore forming a seat for said valve, and a helical spring located in said bore, a portion of said spring having an outer diameter, prior to insertion into said bore, greater than the inner diameter of said bore, the leading edge of said inserted spring being located a preselected distance from said valve seat to limit the movement of said valve away from said seat.
Claim 2
Dependent Claim
163 words
A time delay actuator comprising, a magnetic frame, a tube supported from the frame, a coil encircling said tube, a pole piece forming a closure for one end of said tube, an armature pivotally supported from said frame and rotatable toward and away from said pole piece, a fluid filling said tube, a magnetically permeable core in said tube, said core being movable along the axis of said tube through said fluid under the influence of the magnetic flux generated by said coil, said core including an axial bore therethrough, a ball valve located in said bore, said bore forming a seat for said valve, and a helical spring located in said bore, a portion of said spring having an outer diameter, prior to insertion into said bore, greater than the inner diameter of said bore, the leading edge of said inserted spring being located a preselected distance from said valve seat to limit the movement of said valve away from said seat.
Claim 3
Dependent Claim
22 words
The combination recited in claim 1 wherein the outer diameter of said helical spring is tapered in the direction of said valve.
Claim 4
Dependent Claim
17 words
The combination recited in claim 2 wherein said helical spring is made of a magnetically permeable material.
Claim 5
Dependent Claim
45 words
The combination recited in claim 3 wherein said spring includes a diametrically disposed tang at its leading end, said tang suitable for being grasped during insertion of said spring into said bore to reduce its diameter and thereby permit said spring to enter said bore.
Claim 6
Dependent Claim
169 words
In a time delay actuator including a time delay tube, a solenoid coil wrapped around said tube, a retarding fluid and a movable magnetic core within said tube, a biasing spring for biasing said core to a first position in said tube, said core being movable longitudinally through said tube against the bias of said biasing spring to a second position in response to the magnetic field generated by said coil, said core having formed therethrough an axial bore, a valve housed in said bore, said bore forming a seat for said valve, the improvement comprising resilient means located within said bore on the side of the valve opposite said seat for limiting the movement of said valve away from its seat when said core moves from said second position to said first position, said resilient means being in tensioned condition while in place in said bore to exert an outward force against the interior surface of said bore to thereby hold said means in place in said bore.
Claim 7
Dependent Claim
169 words
In a time delay actuator including a time delay tube, a solenoid coil wrapped around said tube, a retarding fluid and a movable magnetic core within said tube, a biasing spring for biasing said core to a first position in said tube, said core being movable longitudinally through said tube against the bias of said biasing spring to a second position in response to the magnetic field generated by said coil, said core having formed therethrough an axial bore, a valve housed in said bore, said bore forming a seat for said valve, the improvement comprising resilient means located within said bore on the side of the valve opposite said seat for limiting the movement of said valve away from its seat when said core moves from said second position to said first position, said resilient means being in tensioned condition while in place in said bore to exert an outward force against the interior surface of said bore to thereby hold said means in place in said bore.
Claim 8
Dependent Claim
38 words
The combination recited in claim 5 wherein said resilient means comprises a helical stop spring, a portion of said stop spring having an outer diameter, before insertion into said bore, greater than the interior diameter of said bore.
Claim 9
Dependent Claim
34 words
The combination recited in claim 6 wherein said stop spring is tapered in diameter with the leading end of said inserted spring having a smaller diameter than the trailing end of said inserted spring.
Claim 10
Dependent Claim
16 words
The combination recited in claim 7 wherein said spring is made of a magnetically permeable material.
Claim 11
Dependent Claim
19 words
The combination recited in claim 8 wherein the leading end of said inserted spring includes a diametrically disposed tang.
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) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |