Patent IL26240A successfully refreshed from Google Patents.
IL26240A
Expired / Lapsed
IL
⏱️ 0.0 years remaining
Protective device for alternating-current motors against supply asymmetry
Assignee: Erlicki M
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Filing: 1966-07-31
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Granted: —
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Expires: 1986-07-31
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
IL
Data Source
google_patents
Last Synchronized
2026-10-30 22:46
CPC Classifications
—
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
92 words
Δ protective device for a multiphase alternating-current motor against power-supply asymmetry, comprising, in combination: a pick-up coil mounted in proximity to the motor axis, a frequency-selective filter connected to said pick-up coil, said filter being tuned to one of the characteristic frequences of the motor whose signal level differs during symmetric conditions from that level during asymmetrical conditions, and switching means actuated by said filter, said switching means being adapted to interrupt the power supply of the motor whenever the signal reaching said switching means from said filter exceeds a predetermined value.
Claim 2
Dependent Claim
92 words
Δ protective device for a multiphase alternating-current motor against power-supply asymmetry, comprising, in combination: a pick-up coil mounted in proximity to the motor axis, a frequency-selective filter connected to said pick-up coil, said filter being tuned to one of the characteristic frequences of the motor whose signal level differs during symmetric conditions from that level during asymmetrical conditions, and switching means actuated by said filter, said switching means being adapted to interrupt the power supply of the motor whenever the signal reaching said switching means from said filter exceeds a predetermined value.
Claim 3
Dependent Claim
43 words
A device of Claim 1, wherein 'said frequency-selective filter is adapted to substantially attenuate all voltages . excepting those having a frequency of (2 - s)f where f is the frequency of the power supply and s is the slip of the motor.
Claim 4
Dependent Claim
13 words
A device of Claim 1, wherein said frequency-selective filter comprises a twin-tee network.
Claim 5
Dependent Claim
14 words
A device -of Claim 1, wherein said freq ency-selective , filter includes amplifying means.
Claim 6
Dependent Claim
22 words
A device of Claim 1, wherein the pick-up coil has a diameter substantially equal to the inside diameter of the motor stator.
Claim 7
Dependent Claim
20 words
A protective device for multiptiase alternating-current motors against power-supply asymmetry substantially as hereinbefore described by way of example and with
Claim 8
Dependent Claim
20 words
A protective device for multiptiase alternating-current motors against power-supply asymmetry substantially as hereinbefore described by way of example and with
References Cited (Backward Citations)
No citation records indexed.
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