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US3887850A Expired / Lapsed US ⏱️ 0.0 years remaining

Delay circuit for a relay

Assignee: Panasonic Electric Works Co Ltd
•
Filing: 1973-11-14
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Granted: 1975-06-03
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Expires: 1993-11-14
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Abstract

Abstract The delay circuit comprises a differential amplifier having an output connected to the winding of a relay, a non-inverting input connected to the center tap of an ohmic potential divider connected across the voltage supply and inverting input connected to the junction between a first ohmic resistor and a capacitor connected in series therewith to the voltage supply. The output of the amplifier is connected through a diode which blocks when the relay is not energized to the non-inverting input of the amplifier. A second ohmic resistor in series with a reference voltage source is connected in parallel to the first resistor and the capacitor. Those terminals of the second resistor and the capacitor which are not connected to the voltage supply are interconnected by a further diode which conducts in the direction of the voltage supply. The reference voltage is at least equal to twice the threshold voltage of a diode and the first resistor has a high ohmic value with respect to the second ohmic resistor and is shunted by a diode which blocks in the direction of the voltage supply.

Inventors

  • 👤 Wilhelm Sterff

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 05:23
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/023; H03K17/00; H03K17/28

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 271 words
A circuit to delay for a predetermined time interval the response of a relay having an operating winding with one side conneted to one side of a voltage supply and comprising a differential amplifier having an output connected to the other side of the winding and non-inverting input and an inverting input, a potential divider connected across said voltage supply and having a center tap connected to said non-inverting amplifier input, a first resistor and a capacitor in series therewith both connected across said voltage supply, said amplifier inverting input connected between said first resistor and said capacitor, a diode which is blocking when the relay is not energized connected between said amplifier output and said amplifier non-inverting input, a reference voltage source comprising one of fourth and fifth diodes conducting in the direction of said voltage supply or a diode conducting in the direction of said voltage supply and a resistor in series with said diode, a second resistor in series with said reference voltage source and in parallel with said first resistor and said capacitor, said second resistor having a higher ohmic value with respect to said first resistor, a second diode conducting in the direction of the voltage supply connected to those terminals of said first resistor and said capacitor which are not connected to said voltage supply, and a third diode shunting said first resistor and blocking in the direction of said supply voltage, the reference voltage being at least twice the threshold voltage of a diode, said first resistor comprising an adjustable potentiometer having an electrical resistance of about 100-1000 times that of said second resistor.
Claim 2
Dependent Claim 271 words
A circuit to delay for a predetermined time interval the response of a relay having an operating winding with one side conneted to one side of a voltage supply and comprising a differential amplifier having an output connected to the other side of the winding and non-inverting input and an inverting input, a potential divider connected across said voltage supply and having a center tap connected to said non-inverting amplifier input, a first resistor and a capacitor in series therewith both connected across said voltage supply, said amplifier inverting input connected between said first resistor and said capacitor, a diode which is blocking when the relay is not energized connected between said amplifier output and said amplifier non-inverting input, a reference voltage source comprising one of fourth and fifth diodes conducting in the direction of said voltage supply or a diode conducting in the direction of said voltage supply and a resistor in series with said diode, a second resistor in series with said reference voltage source and in parallel with said first resistor and said capacitor, said second resistor having a higher ohmic value with respect to said first resistor, a second diode conducting in the direction of the voltage supply connected to those terminals of said first resistor and said capacitor which are not connected to said voltage supply, and a third diode shunting said first resistor and blocking in the direction of said supply voltage, the reference voltage being at least twice the threshold voltage of a diode, said first resistor comprising an adjustable potentiometer having an electrical resistance of about 100-1000 times that of said second resistor.
Claim 3
Dependent Claim 271 words
A circuit to delay for a predetermined time interval the response of a relay having an operating winding with one side conneted to one side of a voltage supply and comprising a differential amplifier having an output connected to the other side of the winding and non-inverting input and an inverting input, a potential divider connected across said voltage supply and having a center tap connected to said non-inverting amplifier input, a first resistor and a capacitor in series therewith both connected across said voltage supply, said amplifier inverting input connected between said first resistor and said capacitor, a diode which is blocking when the relay is not energized connected between said amplifier output and said amplifier non-inverting input, a reference voltage source comprising one of fourth and fifth diodes conducting in the direction of said voltage supply or a diode conducting in the direction of said voltage supply and a resistor in series with said diode, a second resistor in series with said reference voltage source and in parallel with said first resistor and said capacitor, said second resistor having a higher ohmic value with respect to said first resistor, a second diode conducting in the direction of the voltage supply connected to those terminals of said first resistor and said capacitor which are not connected to said voltage supply, and a third diode shunting said first resistor and blocking in the direction of said supply voltage, the reference voltage being at least twice the threshold voltage of a diode, said first resistor comprising an adjustable potentiometer having an electrical resistance of about 100-1000 times that of said second resistor.
Claim 4
Dependent Claim 271 words
A circuit to delay for a predetermined time interval the response of a relay having an operating winding with one side conneted to one side of a voltage supply and comprising a differential amplifier having an output connected to the other side of the winding and non-inverting input and an inverting input, a potential divider connected across said voltage supply and having a center tap connected to said non-inverting amplifier input, a first resistor and a capacitor in series therewith both connected across said voltage supply, said amplifier inverting input connected between said first resistor and said capacitor, a diode which is blocking when the relay is not energized connected between said amplifier output and said amplifier non-inverting input, a reference voltage source comprising one of fourth and fifth diodes conducting in the direction of said voltage supply or a diode conducting in the direction of said voltage supply and a resistor in series with said diode, a second resistor in series with said reference voltage source and in parallel with said first resistor and said capacitor, said second resistor having a higher ohmic value with respect to said first resistor, a second diode conducting in the direction of the voltage supply connected to those terminals of said first resistor and said capacitor which are not connected to said voltage supply, and a third diode shunting said first resistor and blocking in the direction of said supply voltage, the reference voltage being at least twice the threshold voltage of a diode, said first resistor comprising an adjustable potentiometer having an electrical resistance of about 100-1000 times that of said second resistor.
Claim 5
Dependent Claim 244 words
A circuit to delay for a predetermined time interval the response of a relay having an operating winding with one side connected to one side of a voltage supply and comprising a first differential amplifier having an output connected to the other side of the relay winding and a non-inverting input and an inverting input, a potential divider connected across said voltage supply and having a center tap connected to said non-inverting input, a first resistor and a capacitor in series therewith both connected across said voltage supply, said inverting input connected between said first resistor and said capacitor, a diode blocking when said winding is not energized connected between said amplifier output and said first amplifier non-inverting input, a second differential amplifier having an output and a non-inverting input and an inverting input, a second diode conducting when said relay winding is not energized connected to the output of said first amplifier and to the non-inverting input of said second amplifier, a second resistor connected to said second amplifier non-inverting input and to the side of the capacitor connected to the voltage supply, the second ampliFier inverting input connected between said first resistor and said capacitor, a third diode which blocks when the relay is not energized connected to said second amplifier output and between said first resistor and said capacitor, and a Zener diode connected in reverse between said voltage supply and the side of said capacitor connected to said voltage supply.
Claim 6
Dependent Claim 244 words
A circuit to delay for a predetermined time interval the response of a relay having an operating winding with one side connected to one side of a voltage supply and comprising a first differential amplifier having an output connected to the other side of the relay winding and a non-inverting input and an inverting input, a potential divider connected across said voltage supply and having a center tap connected to said non-inverting input, a first resistor and a capacitor in series therewith both connected across said voltage supply, said inverting input connected between said first resistor and said capacitor, a diode blocking when said winding is not energized connected between said amplifier output and said first amplifier non-inverting input, a second differential amplifier having an output and a non-inverting input and an inverting input, a second diode conducting when said relay winding is not energized connected to the output of said first amplifier and to the non-inverting input of said second amplifier, a second resistor connected to said second amplifier non-inverting input and to the side of the capacitor connected to the voltage supply, the second ampliFier inverting input connected between said first resistor and said capacitor, a third diode which blocks when the relay is not energized connected to said second amplifier output and between said first resistor and said capacitor, and a Zener diode connected in reverse between said voltage supply and the side of said capacitor connected to said voltage supply.
Claim 7
Dependent Claim 50 words
A circuit as claimed in claim 2 wherein the threshold voltage of said Zener diode is greater than the sum of the threshold voltage of said third diode plus the threshold that remains between the second amplifier output and one side of the voltage supply when the relay is energized.

References Cited (Backward Citations)

US2867754A Cited
US3282631A Cited
US3671817A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-06-02 1978-12-02 1979-06-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-06-02 1982-12-02 1983-06-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-06-02 1986-12-02 1987-06-03 $7700.00 Window Closed / Lapsed

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