US3902149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motor protector apparatus
Assignee: Texas Instruments Inc
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Filing: 1974-10-07
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Granted: 1975-08-26
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Expires: 1994-10-07
Abstract
Abstract A motor protector actuable by thermally-responsive means to open electrical contacts is particularly adapted for use embedded in a motor winding where arcs occurring during opening of such contacts would tend to be strongly affected by magnetic fields established within the motor winding. The protector is provided with special means for intercepting and depressing such arcs for shielding the thermally-responsive means from such arcs, whereby the thermally-responsive means retains its thermal response characteristics throughout a long service life.
Inventors
- 👤 Ronald E Senor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:21
CPC Classifications
H; H01; H01H; H01H61/00; H01H61/02; H01H37/00; H01H37/02; H01H37/32; H01H37/52; H01H37/54; H01H37/5418; H01H9/00; H01H9/30; H01H9/34
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
197 words
A motor protector comprising an electrically conductive header member having a plurality of portions including a metal plate part and at least one terminal means, said header portions each being mounted in electrically insulated relation to each other, a rigid electrically conducting contact arm and a rigid electrically conductive heater element secured to respective portions of said header in electrically insulated relation to each other to extend in cantilever relation from said header, a fixed contact mounted at the distal end of said arm, an electrically conductive thermally responsive snap-acting member secured at one end in electrically conductive relation to said element and having a movable contact secured at an opposite end of said member, said thermally responsive member being of a dished configuration and being adapted to move to an inverted dished configuration when subjected to a selected temperature for moving said movable contact into and out of engagement with said fixed contact, and a grid member mounted on said header to extend in cantilever relation therefrom in spaced relation to said arm and said thermally responsive member to shield said thermallyresponsive member from electrical arcs occuring between said contacts during movement of said movable contact.
Claim 2
Dependent Claim
197 words
A motor protector comprising an electrically conductive header member having a plurality of portions including a metal plate part and at least one terminal means, said header portions each being mounted in electrically insulated relation to each other, a rigid electrically conducting contact arm and a rigid electrically conductive heater element secured to respective portions of said header in electrically insulated relation to each other to extend in cantilever relation from said header, a fixed contact mounted at the distal end of said arm, an electrically conductive thermally responsive snap-acting member secured at one end in electrically conductive relation to said element and having a movable contact secured at an opposite end of said member, said thermally responsive member being of a dished configuration and being adapted to move to an inverted dished configuration when subjected to a selected temperature for moving said movable contact into and out of engagement with said fixed contact, and a grid member mounted on said header to extend in cantilever relation therefrom in spaced relation to said arm and said thermally responsive member to shield said thermallyresponsive member from electrical arcs occuring between said contacts during movement of said movable contact.
Claim 3
Dependent Claim
40 words
A motor protector as set forth in claim 1 wherein the grid member is perforated so that an electrical path extending between the distal and support ends of the grid have a length greater than the length of the grid.
Claim 4
Dependent Claim
44 words
A motor protector as set forth in claim 2 wherein a cup-shaped body having an open end with a rim which is welded at said rim in sealed relation to said header member for enclosing the heater, arc control grid, contacts and thermally-responsive members.
Claim 5
Dependent Claim
187 words
A motor protector comprising a header member, two terminals mounted on said header member in electrically insulated relation to each other and to said header member, a rigid electrically conducting metallic contact arm, a rigid electrically conductive heater element, said arm and element each being secured to one of said terminals to extend in cantilever relation therefrom, a fixed contact mounted at the distal end of said arm, an electrically conductive thermally responsive snap-acting member secured at one end to said heater element and having a movable contact secured at the opposite end of said member, said member being of the dish shaped configuration and being adapted to move to an inverted dished configuration when subjected to a selected temperature for moving said movable contact into and out of engagement with said fixed contact, and an electrically conductive arc control member mounted on said header to extend in cantilever relation from the headerplate between said contact arm and said thermally responsive member to protect said thermally responsive member from arcs occurring during the movement of said movable contact into and out of engagement with said fixed contact.
Claim 6
Dependent Claim
187 words
A motor protector comprising a header member, two terminals mounted on said header member in electrically insulated relation to each other and to said header member, a rigid electrically conducting metallic contact arm, a rigid electrically conductive heater element, said arm and element each being secured to one of said terminals to extend in cantilever relation therefrom, a fixed contact mounted at the distal end of said arm, an electrically conductive thermally responsive snap-acting member secured at one end to said heater element and having a movable contact secured at the opposite end of said member, said member being of the dish shaped configuration and being adapted to move to an inverted dished configuration when subjected to a selected temperature for moving said movable contact into and out of engagement with said fixed contact, and an electrically conductive arc control member mounted on said header to extend in cantilever relation from the headerplate between said contact arm and said thermally responsive member to protect said thermally responsive member from arcs occurring during the movement of said movable contact into and out of engagement with said fixed contact.
Claim 7
Dependent Claim
71 words
A motor protector as set forth in claim 4 wherein said arc control grid member has a plate portion extending away from the headerplate to a point closely adjacent to said fixed contact, having a width at least as great as said thermally responsive member and having two portions extending from the distal end of said plate portion to a height at least equal to the midpoint of said fixed contact.
Claim 8
Dependent Claim
40 words
A motor protector as set forth in claim 5 wherein the grid member is perforated so that an electrical path extending between the distal and support ends of the grid have a length greater than the length of the grid.
Claim 9
Dependent Claim
45 words
A motor protector as set forth in claim 6 wherein a cup-shaped body having an open end with a rim which is welded at said rim in sealed relaTion to said header member for enclosing the heater, arc control grid, contacts and thermally responsive members.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |