Patent US3700964A successfully refreshed from Google Patents.
US3700964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Motor overload protector and voltage cut-out device
Assignee: Individual
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Filing: 1970-09-22
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Granted: 1972-10-24
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Expires: 1990-09-22
Abstract
Abstract A current responsive motor overload protector for a three-phase AC motor wherein there are three bimetallic elements each of which is incorporated in a switch, each such switch being in series with a phase lead of a three-phase AC voltage source and also with a motor lead. Each of the bimetallic elements normally maintaining its respective switch in a closed position and opening automatically or bending towards an open condition due to the heating effects of a current passing through it when the motor is in an overload condition. A further circuit is included in the protector which is responsive to the opening, or bending, of each bimetallic element switch and when one of a bimetallic element switch opens at least in part, it energizes the further circuit which actuates a solenoid which, in turn, simultaneously causes each of the bimetallic element switches to open in a quick acting movement. A movable biased toggle mechanically secures the solenoid so that the bimetallic strip switches are retained in the open position until the toggle is manually reset. The toggle also opens a switch in a further circuit which serves to secure the current to the solenoid. An indicia means such as a lamp, buzzer or bell, or combination thereof, is connected between one of the electrical phase sources on one side and to a ground or a motor-phase lead via contacts which are closed responsive to the opening of each metallic switch on the other side. Warning indicia may be provided which is energized by a contact with each bimetallic element prior to the opening thereof when the overload condition of the metallic element is not sufficient to energize the further circuit.
Inventors
- 👤 Thomas Moore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:18
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/08; H02H3/00; H02H3/02; H02H3/04; H02H7/085
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
218 words
A device for effecting and indicating the discontinuance of voltAge to a three-phase AC electrical motor when said motor is overloaded which comprises: a receptacle, three quick acting electrical heat switches mounted in said receptacle, three circuit means in said receptacle, each of said circuit means being connectable to one phase of a three-phase AC source, each of said circuit means being in series through one of said switches with said three-phase AC motor, said motor having a predetermined power rating, each of said switches being normally closed and adapted to open when current passing therethrough exceeds an amount relative to the power rating of said motor, a solenoid in said receptacle operatively connected to each of said switches whereby when said solenoid is actuated, each of said switches is opened by said solenoid, three electrical contact means mounted in said receptacle, each relative to a different one of said switches whereby when one of said switches opens at least in part it makes an electrical connection with its corresponding contact means, further circuit means interconnecting each of said contact means, and said solenoid for actuating said solenoid whereby when one of said switches opens sufficiently to make an electrical connection with its corresponding contact means, said solenoid is actuated and all of said three switches are opened.
Claim 2
Independent Claim
218 words
A device for effecting and indicating the discontinuance of voltAge to a three-phase AC electrical motor when said motor is overloaded which comprises: a receptacle, three quick acting electrical heat switches mounted in said receptacle, three circuit means in said receptacle, each of said circuit means being connectable to one phase of a three-phase AC source, each of said circuit means being in series through one of said switches with said three-phase AC motor, said motor having a predetermined power rating, each of said switches being normally closed and adapted to open when current passing therethrough exceeds an amount relative to the power rating of said motor, a solenoid in said receptacle operatively connected to each of said switches whereby when said solenoid is actuated, each of said switches is opened by said solenoid, three electrical contact means mounted in said receptacle, each relative to a different one of said switches whereby when one of said switches opens at least in part it makes an electrical connection with its corresponding contact means, further circuit means interconnecting each of said contact means, and said solenoid for actuating said solenoid whereby when one of said switches opens sufficiently to make an electrical connection with its corresponding contact means, said solenoid is actuated and all of said three switches are opened.
Claim 3
Dependent Claim
39 words
A device in accordance with claim 1 which comprises toggle means mounted in said receptacle relative to said solenoid, said toggle means adapted to engage said solenoid upon its actuation and maintain said three switches in an opened position.
Claim 4
Dependent Claim
47 words
A device in accordance with claim 2 which comprises a further switch in said further circuit means operatively connected to said toggle means whereby when said toggle means engages said solenoid to maintain said three switches in an opened position, electrical energy to said solenoid is secured.
Claim 5
Dependent Claim
41 words
A device in accordance with claim 1 which comprises indicia means mounted on said receptacle, said indicia means having a high electrical resistance compared to said motor, said indicia means being activated electrically by the energization of said further circuit means.
Claim 6
Dependent Claim
44 words
A device in accordance with claim 4, said indicia means being electrically in series with and between a phase of said AC source and a phase of said AC motor when one of said switches is opened, voltage across said pass is substantially eliminated.
Claim 7
Dependent Claim
14 words
A device in accordance with claim 5 wherein said indicia means is a lamp.
Claim 8
Dependent Claim
16 words
A device in accordance with claim 5 where said indicia means is a noise producing means.
Claim 9
Dependent Claim
31 words
A device in accordance with claim 5 wherein there are three of said indicia means, each of said indicia means being in series with a different of said AC motor phases.
Claim 10
Dependent Claim
28 words
A device in accordance with claim 8 wherein one of said indicia means is a lamp and the other of said indicia means is a noise producing means.
Claim 11
Dependent Claim
19 words
A device in accordance with claim 1 wherein each said switch includes a bimetallic member as an actuating member.
Claim 12
Independent Claim
176 words
A device for effecting the complete discontinuance of electrical power to a three-phase AC electrical motor when said motor is overloaded which comprises: insulated support means, three switch means each including a bimetallic element mounted on said support means, three circuit means mounted in said support means, each of said circuit means being connectable to one phase of a three phase AC source, each of said circuit means being in series through the bimetallic element in one of said switches with a phase of said three-phase AC motor, said motor having a predetermined power rating, each bimetallic element of said switch normally carrying the full current of its corresponding phase and being operatively connected with disconnect means adapted to disconnect said phase when the current in said phase exceeds a predetermined amount in response to the bending of said bimetallic element, and interlocking means associated with sAid disconnect means adapted to disconnect simultaneously the three phases to said motor in response to activation of said disconnect means by the bending of any of said bimetallic elements.
Claim 13
Independent Claim
176 words
A device for effecting the complete discontinuance of electrical power to a three-phase AC electrical motor when said motor is overloaded which comprises: insulated support means, three switch means each including a bimetallic element mounted on said support means, three circuit means mounted in said support means, each of said circuit means being connectable to one phase of a three phase AC source, each of said circuit means being in series through the bimetallic element in one of said switches with a phase of said three-phase AC motor, said motor having a predetermined power rating, each bimetallic element of said switch normally carrying the full current of its corresponding phase and being operatively connected with disconnect means adapted to disconnect said phase when the current in said phase exceeds a predetermined amount in response to the bending of said bimetallic element, and interlocking means associated with sAid disconnect means adapted to disconnect simultaneously the three phases to said motor in response to activation of said disconnect means by the bending of any of said bimetallic elements.
Claim 14
Dependent Claim
24 words
A device in accordance with claim 11 wherein said disconnect means includes a single solenoid which directly effects the simultaneous disconnection of said phases.
Claim 15
Dependent Claim
49 words
A device in accordance with claim 12 wherein said disconnect means includes toggle means operative with said solenoid whereby when said disconnect means is activated, said toggle means causes said solenoid to be retained in a position wherein said phases remain disconnected until said toggle means is manually reset.
Claim 16
Independent Claim
116 words
A device for effecting the discontinuance of current to an electrical AC motor when said motor is overloaded which comprises: insulated support means, switch means including a bimetallic element mounted on said support means, circuit means mounted in said support means, said circuit means being connectable to current for energizing said motor and in series with the bimetallic element of said switch means whereby the current which energizes said motor is conducted through said bimetallic element, and indicia means operatively connected to said switch means whereby when the current passing through said bimetallic element exceeds a predetermined amount, said switch activates said indicia means and at the same time disconnects said current which energizes said motor.
Claim 17
Independent Claim
116 words
A device for effecting the discontinuance of current to an electrical AC motor when said motor is overloaded which comprises: insulated support means, switch means including a bimetallic element mounted on said support means, circuit means mounted in said support means, said circuit means being connectable to current for energizing said motor and in series with the bimetallic element of said switch means whereby the current which energizes said motor is conducted through said bimetallic element, and indicia means operatively connected to said switch means whereby when the current passing through said bimetallic element exceeds a predetermined amount, said switch activates said indicia means and at the same time disconnects said current which energizes said motor.
Claim 18
Dependent Claim
14 words
A device in accordance with claim 14 wherein said indicia means is a lamp.
References Cited (Backward Citations)
US2189591A
Cited
US3530337A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |