Cycling limiting circuitry and method for electrical apparatus
First Claim
1. In electrical apparatus of the type including means operated by said apparatus, a source of electrical power, and operating means connected to the power source and operative for applying a voltage across the operated means, circuitry for limiting the cycling of the operated means, wherein said means is alternately on and off, by disconnecting the operating means from the power source to protect the operating means when a cycling limit is reached, comprising:
- normally closed switching means connecting the operating means to the power source;
a resistor connected to the power source and to the operated means, whereby a voltage drop occurs across the resistor upon the operating means cycling;
means connected across the resistor and responsive to the number of times the operated means cycles and providing an output when said means cycles a predetermined number of times; and
means connected to the last mentioned means and to the switching means and responsive to the output from said last mentioned means for opening the switching means to disconnect the operating means from the power source.
5 Assignments
0 Petitions
Accused Products
Abstract
For use with apparatus of the type including a power supply, means operated by the power from the power supply and means operably connected between the power supply and the means operated thereby for applying power of a predetermined magnitude for operating said operated means circuitry and method wherein a resistor is connected to the apparatus and cycling limiting circuitry is connected across the resistor and is responsive to the voltage drop thereacross when the operated means cycles, i.e. turns off and then on. The cycling limiting circuitry counts the number of cycles and after a predetermined number of cycles occurs provides an output which is effective for interrupting power from the power supply, whereby the operating means is removed from the circuit to protect the latter from damage due to unlimited cycling.
-
Citations
18 Claims
-
1. In electrical apparatus of the type including means operated by said apparatus, a source of electrical power, and operating means connected to the power source and operative for applying a voltage across the operated means, circuitry for limiting the cycling of the operated means, wherein said means is alternately on and off, by disconnecting the operating means from the power source to protect the operating means when a cycling limit is reached, comprising:
-
normally closed switching means connecting the operating means to the power source; a resistor connected to the power source and to the operated means, whereby a voltage drop occurs across the resistor upon the operating means cycling; means connected across the resistor and responsive to the number of times the operated means cycles and providing an output when said means cycles a predetermined number of times; and means connected to the last mentioned means and to the switching means and responsive to the output from said last mentioned means for opening the switching means to disconnect the operating means from the power source. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. In electrical apparatus of the type including a high pressure sodium lamp, a source of electrical power and ballast-starter means operatively connected to the power source and to the lamp, said power source being normally operative for supplying power to the lamp and to the ballast-starter means to light the lamp, circuitry for limiting the cycling of the lamp, wherein the lamp is alternately on and off, to protect the ballast-starter means, comprising:
-
normally closed switching means connecting the ballast-starter means to the power source; a resistor connected to the power source and to the lamp, whereby a voltage drop occurs across the resistor upon the lamp cycling; means connected accoss the resistor and responsive to the number of time and lamp cycles and providing an output when said lamp cycles a predetermined number of times; and means connected to the last mentioned means and to the switching means and responsive to the output from said last mentioned means for opening the switching means to disconnect the ballast-starter means from the power source. - View Dependent Claims (14)
-
-
15. A method for protecting an operating means connected to a power source and operative for applying a voltage across an operated means, by limiting the cycling of the operated means, wherein said means is alternatively on and off, by disconnecting the power source from the operating means when a cycling limit is reached, comprising:
-
connecting a resistor to the power source and to the operated means; comparing the voltage across the resistor to a reference voltage and providing an output when the voltage across the resistor drops below the reference voltage a predetermined number of times, said output indicating the cycling of the operated means the predetermined number of times; and utilizing the last mentioned output for disconnecting the power source from the operating means. - View Dependent Claims (16, 17)
-
-
18. A method for protecting ballast-starter means connected to a power source and operative for applying a voltage for turning on a high pressure sodium lamp, by limiting the cycling of the lamp, wherein said lamp is alternately on and off, by disconnecting the power source from the ballast-starter means when a cycling limit is reached, comprising:
-
connecting a resistor to the power source and to the lamp; comparing the voltage across the resistor to a reference voltage and providing an output when the voltage across the resistor drops below the reference voltage, said output indicating the cycling of the lamp; counting the number of times the cycling occurs and providing an output upon reaching a predetermined count; and utilizing the last mentioned output for disconnecting the power source from the operating means.
-
Specification