US3622930A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motor protector apparatus and method
Assignee: Texas Instruments Inc
•
Filing: 1969-10-16
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Granted: 1971-11-23
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Expires: 1989-10-16
Abstract
Abstract A motor protector particularly suited for use with appliance motors having a rate of rise up to 30* C. per second and higher, comprising a heater/thermostatic disc assembly in which the major heat transfer from the heater to the disc is by conduction. The disc is supported solely by the heater in such a way that the first ''''on'''' time is short and the first ''''off'''' time is long. The structure is such that the standard deviation of the first cycle ''''on'''' time is within a 3 second range necessary to protect such motors. The assembly is placed in a heat conductive can with the heater cantilever mounted on the bottom wall thereof. The thermostatic disc is in turn cantilever mounted on the heater, a contact is attached to the distal free end of the disc and is adapted to engage and disengage a stationary contact mounted on a cover which is clampingly attached to the can but electrically insulated therefrom. The device is calibrated by applying a force to the can in the vicinity of the heater mount to change the prestress of the contacts.
Inventors
- 👤 John R D Entremont
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:34
CPC Classifications
H; H01; H01H; H01H37/00; H01H37/02; H01H37/32; H01H37/52; H01H37/54; H01H37/5418; H02; H02K; H02K11/00; H02K11/20; H02K11/25
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
209 words
A motor protector comprising an electrically conductive base, a rigid elongated heater element having two opposite ends and a portion located intermediate the two ends which generates an increased amount of heat relative to the remainder thereof, one end formed with a relatively large flange integral with the heater, the flange secured to the conductive base so that the heater element is cantilever mounted on the base end having a first surface of greater width than a second surface, a thermostatic element cantilever mounted on the other end of the heater element in a plane generally normal to the first surface and extending generally along the length of the heat generating portions of the heaTer, a movable and a stationary contact, the stationary contact mounted on terminal means electrically insulated from the heater element, the movable contact mounted on the thermostatic element and adapted to move into and out of engagement with the stationary contact, and terminal means electrically connected to the heater element; the thermostatic element, in the vicinity of the movable contact, moves toward the said portion located intermediate the ends of the heater element when the disc is in the contacts disengaged position to enhance the heat transfer from the heater element to the thermostatic element.
Claim 2
Dependent Claim
209 words
A motor protector comprising an electrically conductive base, a rigid elongated heater element having two opposite ends and a portion located intermediate the two ends which generates an increased amount of heat relative to the remainder thereof, one end formed with a relatively large flange integral with the heater, the flange secured to the conductive base so that the heater element is cantilever mounted on the base end having a first surface of greater width than a second surface, a thermostatic element cantilever mounted on the other end of the heater element in a plane generally normal to the first surface and extending generally along the length of the heat generating portions of the heaTer, a movable and a stationary contact, the stationary contact mounted on terminal means electrically insulated from the heater element, the movable contact mounted on the thermostatic element and adapted to move into and out of engagement with the stationary contact, and terminal means electrically connected to the heater element; the thermostatic element, in the vicinity of the movable contact, moves toward the said portion located intermediate the ends of the heater element when the disc is in the contacts disengaged position to enhance the heat transfer from the heater element to the thermostatic element.
Claim 3
Dependent Claim
27 words
A motor protector according to claim 3 in which the heater element has a first surface to second surface ratio greater than approximately 1 1/2 to 1.
Claim 4
Dependent Claim
53 words
A motor protector according to claim 1 in which the free distal end of the thermostatic element mounts the movable contact on one side and in which the other side of the thermostatic element is biased against a heat generating portion of the heater when the contacts are in the disengaged ''''off'''' position.
Claim 5
Dependent Claim
30 words
A motor protector according to claim 3 in which the heat generating portion of the heater against which the thermostatic element is biased comprises a protuberance extending from the heater.
Claim 6
Dependent Claim
20 words
A motor protector according to claim 4 in which the heater element includes a constricted portion contiguous to the protuberance.
Claim 7
Dependent Claim
174 words
A motor protector having a rigid barlike heater element one portion of which generates an increased amount of heat relative to the remainder thereof, the heater element having a first surface of greater width than a second surface, a thermostatic element cantilever mounted on the heater element remote from said portion in a plane generally normal to the first surface and extending generally along the length of the heat generating portions of the heater and movable from a first ''''off'''' position to a second ''''on'''' position and back, the free distal end of the thermostatic element being biased against a heat generating portion of the heater intermediate the ends thereof and contiguous with that portion of the heater which generates the increased amount of heat when the element is in the first ''''off'''' position, the heater element being the sole support for the thermostatic element, whereby the standard deviation of first cycle ''''on'''' time is 0.5 seconds or less and the ratio of ''''off'''' to ''''on'''' times is greater than about 5 to 1.
Claim 8
Dependent Claim
174 words
A motor protector having a rigid barlike heater element one portion of which generates an increased amount of heat relative to the remainder thereof, the heater element having a first surface of greater width than a second surface, a thermostatic element cantilever mounted on the heater element remote from said portion in a plane generally normal to the first surface and extending generally along the length of the heat generating portions of the heater and movable from a first ''''off'''' position to a second ''''on'''' position and back, the free distal end of the thermostatic element being biased against a heat generating portion of the heater intermediate the ends thereof and contiguous with that portion of the heater which generates the increased amount of heat when the element is in the first ''''off'''' position, the heater element being the sole support for the thermostatic element, whereby the standard deviation of first cycle ''''on'''' time is 0.5 seconds or less and the ratio of ''''off'''' to ''''on'''' times is greater than about 5 to 1.
Claim 9
Dependent Claim
36 words
A motor protector according to claim 6 in which the heat generating portion of the heater which is biased against the free distal end of the thermostatic element comprises a protuberance extending from the heater element.
Claim 10
Dependent Claim
20 words
A motor protector according to claim 7 in which the heater element includes a constricted portion contiguous to the protuberance.
Claim 11
Dependent Claim
20 words
A motor protector according to claim 6 in which the heater element is cantilever mounted on an electrically conductive support.
References Cited (Backward Citations)
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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) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |