US3739224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crt sweep return circuit
Assignee: Bendix Corp
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Filing: 1971-01-26
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Granted: 1973-06-12
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Expires: 1991-01-26
Abstract
Abstract A circuit for returning the sweep of a cathode ray tube to the initial horizontal position is described. Sweep voltages are applied to a transistor and directed to the yoke coil of the CRT through a linear high-voltage DC coil. The linear coil is in parallel with the yoke coil, and conduction of the transistor controls the sweep voltages to the yoke coil. As the transistor responds to the sweep voltages, the yoke coil voltage changes to control the spot sweep and return it to the initial position at the end of each sweep. A diode causes the circuit to discharge into the power supply to greatly increase the efficiency of the circuit.
Inventors
- 👤 W Morrey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:17
CPC Classifications
H; H03; H03K; H03K4/00; H03K4/06; H03K4/08; H03K4/48; H03K4/60; H03K4/62
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
208 words
A deflection circuit for a cathode ray tube having a deflection coil for controlling the sweep of the spot across the face of said cathode ray tube in response to the reception of sweep signals comprising: electron control means for receiving said sweep signals and providing a deflection current to said deflection coil, said electron control means having an on and an off conductive state; means for receiving a biasing voltage from a supply and applying said biasing voltage to said electron control means; inductive means coupled to said electron control means and receiving said deflection current; said deflection coil and said inductive means being connected to form a current loop so that said deflection current flows through said inductive means and said deflection coil; and unidirectional conductive means across said electron control means and said inductive means, said unidirectional conductive means having on and off conductive status and being poled so that said conductive states are opposite to the conductive status of said electron control means so that said deflection current flows through said current loop and said deflection coil receives said deflection current when electron control means is conductive and said deflection coil discharges through said unidirectional conductive means when said electron control means is non-conductive.
Claim 2
Dependent Claim
208 words
A deflection circuit for a cathode ray tube having a deflection coil for controlling the sweep of the spot across the face of said cathode ray tube in response to the reception of sweep signals comprising: electron control means for receiving said sweep signals and providing a deflection current to said deflection coil, said electron control means having an on and an off conductive state; means for receiving a biasing voltage from a supply and applying said biasing voltage to said electron control means; inductive means coupled to said electron control means and receiving said deflection current; said deflection coil and said inductive means being connected to form a current loop so that said deflection current flows through said inductive means and said deflection coil; and unidirectional conductive means across said electron control means and said inductive means, said unidirectional conductive means having on and off conductive status and being poled so that said conductive states are opposite to the conductive status of said electron control means so that said deflection current flows through said current loop and said deflection coil receives said deflection current when electron control means is conductive and said deflection coil discharges through said unidirectional conductive means when said electron control means is non-conductive.
Claim 3
Dependent Claim
25 words
The circuit of claim 1 wherein said unidirectional conductive means is a diode, said diode being reverse biased when said electron control means is conductive.
Claim 4
Dependent Claim
36 words
The circuit of claim 2 wherein said electron control means is a transistor, said sweep voltages being applied to the base of said transistor and said biasing voltage being applied to the emitter of said transistor.
Claim 5
Dependent Claim
26 words
The circuit of claim 1 wherein said inductive means is a linear core coil, and said discharge through said diode is directed to said power supply.
Claim 6
Dependent Claim
21 words
The circuit of claim 4 wherein said linear core coil has approximately ten times as much inductance as said deflection coil.
Claim 7
Dependent Claim
36 words
The circuit of claim 1 wherein said electron control means is a transistor, said sweep voltages being applied to the base of said transistor and said biasing voltage being applied to the emitter of said transistor.
Claim 8
Dependent Claim
25 words
The circuit of claim 6 wherein said unidirectional conductive means is a diode, said diode being reverse biased when said electron control means is conductive.
Claim 9
Dependent Claim
14 words
The circuiT of claim 7 wherein said inductive means is a linear core coil.
Claim 10
Dependent Claim
21 words
The circuit of claim 8 wherein said linear core coil has approximately ten times as much inductance as said deflection coil.
Claim 11
Dependent Claim
31 words
The circuit of claim 9 further including an additional coil inductively coupled to said linear core coil so that the voltage across said additional coil is dependent upon said sweep signals.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |