US4015171A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Resettable overcurrent-protected direct current power supply
Assignee: U S Holding Co Inc
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Filing: 1976-02-06
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Granted: 1977-03-29
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Expires: 1996-02-06
Abstract
Abstract A bistable magnetic switch circuit includes one terminal coupled to a source of direct current voltage, a contact coupled to the other terminal of the bistable switch circuit and an armature controlled by the bistable switch circuit to make and break contact with the contact, the bistable switch circuit being energized at a given trip-rated current. A transistor has its collector coupled to the other terminal of the bistable switch circuit, its emitter coupled to a utilizing load and its base coupled to the armature remote from the contact, the transistor being rendered non-conductive when the bistable switch circuit is energized to provide the desired overcurrent protection. A reset switch is coupled between the other terminal of the bistable switch circuit and ground potential to reset the bistable switch to prepare the bistable switch circuit to protect against a continuing or a new overcurrent condition.
Inventors
- 👤 Dale Lloyd Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:23
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/08; H02H3/087; H02H3/02; H02H3/05
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
266 words
A resettable overcurrent-protected direct current power supply comprising: a source of direct current voltage; a utilizing load; a bistable magnetic switch circuit having one terminal coupled to said source of direct current voltage, a contact coupled to the other terminal of said bistable switch circuit and an armature controlled by said bistable switch circuit to make and break contact with said contact, said bistable switch circuit being energized at a given trip-rated current; a transistor having its collector coupled to said other terminal of said bistable switch circuit, its emitter coupled to said load and its base coupled to said armature remote from said contact; and a reset switch coupled to said other terminal of said bistable switch circuit having a normal position to complete a portion of said bistable switch circuit and a momentary contact position, said reset switch being actuated to said momentary contact position after said bistable switch circuit has been energized due to an overcurrent condition to place said armature and said contact in a break state to render said transistor non-conductive and providing the desired overcurrent-protection, said bistable switch circuit de-energizing prior to actuation of said reset switch but said armature and said contact remaining in a break state and actuation of said reset switch causes said bistable switch circuit to re-energize, and the return of said reset switch to said normal position de-energizing said bistable switch circuit to cause said armature and said contact to assume a make state and render said transistor conductive to prepare said bistable switch circuit to protect against a continuing or a new overcurrent condition.
Claim 2
Dependent Claim
266 words
A resettable overcurrent-protected direct current power supply comprising: a source of direct current voltage; a utilizing load; a bistable magnetic switch circuit having one terminal coupled to said source of direct current voltage, a contact coupled to the other terminal of said bistable switch circuit and an armature controlled by said bistable switch circuit to make and break contact with said contact, said bistable switch circuit being energized at a given trip-rated current; a transistor having its collector coupled to said other terminal of said bistable switch circuit, its emitter coupled to said load and its base coupled to said armature remote from said contact; and a reset switch coupled to said other terminal of said bistable switch circuit having a normal position to complete a portion of said bistable switch circuit and a momentary contact position, said reset switch being actuated to said momentary contact position after said bistable switch circuit has been energized due to an overcurrent condition to place said armature and said contact in a break state to render said transistor non-conductive and providing the desired overcurrent-protection, said bistable switch circuit de-energizing prior to actuation of said reset switch but said armature and said contact remaining in a break state and actuation of said reset switch causes said bistable switch circuit to re-energize, and the return of said reset switch to said normal position de-energizing said bistable switch circuit to cause said armature and said contact to assume a make state and render said transistor conductive to prepare said bistable switch circuit to protect against a continuing or a new overcurrent condition.
Claim 3
Dependent Claim
120 words
A power supply according to claim 1, wherein said source of direct current voltage includes a source of alternating current voltage, a transformer having a primary winding coupled to said source of alternating current voltage and a secondary winding, a full wave bridge rectifier having first pair diagonally related terminals coupled across said secondary winding and a second pair of diagonally related terminals, one terminal of said second pair of terminals being coupled to ground potential, a first capacitor coupled between said other terminal of said second pair of terminals and said ground potential for peak-charging filtering, and a first resistor coupled in shunt relation with said first capacitor to discharge said capacitor when said power supply is turned off.
Claim 4
Dependent Claim
73 words
A power supply according to claim 2, further including a second resistor having one terminal coupled to said other terminal of said second pair of terminals for current limiting under a shorted-output condition, and a fuse having one terminal coupled to the other terminal of said second resistor and the other terminal coupled to said one terminal of said bistable switch circuit, said fuse providing redundant overcurrent protection at said given trip-rated current.
Claim 5
Dependent Claim
98 words
A power supply according to claim 3, wherein said bistable switch circuit includes a coil coupled between said one terminal and said other terminal of said bistable switch circuit, a bistable link coupled between said coil and said armature, a third resistor coupled between said one terminal of said bistable swtich circuit and said normal position of said reset switch to desensitize the operation of said coil, and a second capacitor coupled in shunt relation with said coil to reduce the range of vibration of said armature for positive armature stroke at and below said given trip-rated current.
Claim 6
Dependent Claim
42 words
A power supply according to claim 4, further including a fourth resistor coupled between said momentary contact position of said reset switch and said ground potential, said fourth resistor having a value of resistance to draw normal operating current for said coil.
Claim 7
Dependent Claim
29 words
A power supply according to claim 5, further including a fifth resistor coupled between said base and said armature remote from said contact to provide a base limiting resistor.
Claim 8
Dependent Claim
31 words
A power supply according to claim 6, further including a diode coupled between said collector and said emitter opposing normal current flow for quenching transients during switching-off time of said transistor.
Claim 9
Dependent Claim
70 words
A power supply according to claim 1, further including a first resistor having one terminal coupled to said source of direct current voltage for current limiting under a shortedoutput condition, and a fuse having one terminal coupled to the other terminal of said first resistor and the other terminal coupled to said one terminal of said bistable switch circuit, said fuse providing redundant overcurrent protection at said given trip-rated current.
Claim 10
Dependent Claim
98 words
A power supply according to claim 8, wherein said bistable switch circuit includes a coil coupled between said one terminal and said other terminal of said bistable switch circuit, a bistable link coupled between said coil and said armature, a second resistor coupled between said one terminal of said bistable switch circuit and said normal position of said reset switch to desensitize the operation of said coil, and, a first capacitor coupled in shunt relation with said coil to reduce the range of vibration of said armature for positive armature strokes at and below said given triprated current.
Claim 11
Dependent Claim
41 words
A power supply according to claim 9, further including a third resistor coupled between said momentary contact position of said reset switch and ground potential, said third resistor having a value of resistance to draw normal operating current for said coil.
Claim 12
Dependent Claim
29 words
A power supply according to claim 10, further including a fourth resistor coupled between said base and said armature remote from said contact to provide a base limiting resistor.
Claim 13
Dependent Claim
30 words
A power supply according to claim 11, further including a diode coupled between said collector and said emitter opposing normal current flow for quenching transients during switching-off of said transistor.
Claim 14
Dependent Claim
98 words
A power supply according to claim 1, wherein said bistable switch circuit includes a coil coupled between said one terminal and said other terminal of said bistable switch circuit, a bistable link coupled between said coil and said armature, a first resistor coupled between said one terminal of said bistable switch circuit and said normal position of said reset switch to desensitize the operation of said coil, and a first capacitor coupled in shunt relation with said coil to reduce the range of vibration of said armature for positive armature strokes at and below said given triprated current.
Claim 15
Dependent Claim
41 words
A power supply according to claim 13, further including a second resistor coupled between said momentary contact position of said reset switch and ground potential, said second resistor having a value of resistance to draw normal operating current for said coil.
Claim 16
Dependent Claim
29 words
A power supply according to claim 14, further including a third resistor coupled between said base and said armature remote from said contact to provide a base limiting resistor.
Claim 17
Dependent Claim
31 words
A power supply according to claim 15, further including a diode coupled between said collector and said emitter opposing normal current flow for quenching transients during switching-off time of said transistor.
Claim 18
Dependent Claim
43 words
A power supply according to claim 1, further including a first resistor coupled between said momentary contact position of said reset switch and ground potential, said first resistor having a value of resistance to draw normal operating current for said bistable switch circuit.
Claim 19
Dependent Claim
29 words
A power supply according to claim 17, further including a second resistor coupled between said base and said armature remote from said contact to provide a base limiting resistor.
Claim 20
Dependent Claim
31 words
A power supply according to claim 18, further including a diode coupled between said collector and said emitter opposing normal current flow for quenching transients during switching-off time of said transistor.
Claim 21
Dependent Claim
29 words
A power supply according to claim 1, further including a first resistor coupled between said base and said armature remote from said contact to provide a base limiting resistor.
Claim 22
Dependent Claim
31 words
A power supply according to claim 20, further including a diode coupled between said collector and said emitter opposing normal current flow for quenching transients during switching-off time of said transistor.
Claim 23
Dependent Claim
31 words
A power supply according to claim 1, further including a diode coupled between said collector and said emitter opposing normal current flow for quenching transients during switching-off time of said transistor.
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) | 1980-03-28 | 1980-09-27 | 1981-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-28 | 1984-09-27 | 1985-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-28 | 1988-09-27 | 1989-03-29 | $7700.00 | Window Closed / Lapsed |