Alarm system including remote signalling means
First Claim
1. In an alarm system including an alarm circuit and alarm sensing means the state of which is changeable between a non-alarm condition and an alarm condition, the improvement comprising pulsing means connected to said alarm sensing means for generating a substantially constant voltage in said non-alarm condition and a pulsating voltage in said alarm condition of said alarm sensing means;
- switch means for enabling and disabling the alarm circuit and for providing higher and lower reference voltage as a function of the enabled and disabled conditions of the alarm circuit; and
indicating means connected between said pulsing and switching means and adapted to permit current flow in each of two opposite directions therethrough as a function of the relative voltages provided by both said pulsating and switching means across said indicating means, said indicating means providing a different indication for each of the two directions of current flow therethrough, whereby a total of at least four indications may be obtained by selective passage of currents through said indicating means which currents may flow in one of said two opposing directions and which may be zero, constant or pulsed in each of said directions to thereby provide said indications in either constant or in pulsed form.
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Accused Products
Abstract
An improved alarm system is disclosed which includes one or more remote stations. Each remote station is connected to the central or control station by only three conductors or leads. The control and remote stations each include a pair of back-to-back LED diodes, the diodes of each pair emitting a different color light when current flows therethrough. The control and remote stations each also includes a key switch which is operative to "enable" and "disable" the alarm circuitry at the control station. By controlling the direction as well as the wave shape of the currents passing through the LED diodes, four different visual signals may be provided at the control and remote stations to indicate the status of the alarm system. Actuation of any of the key switches reverses the current through the LED diodes so that the different colors are indicated when the alarm system is "enabled" or "disabled". Pulsing means is provided at the control station for producing either a constant current through the LED diodes when an alarm condition does not exist, and a pulsed current when an alarm condition is generated. The current in each direction can be pulsed through the LED diodes so that each pair of back-to-back diodes can emit four distinguishable visible signals indicative of different conditions of the alarm system. A fifth indication may be provided by essentially the same circuitry when a parallel delay loop is provided in addition to the main loop to indicate the condition of the delay loop.
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Citations
13 Claims
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1. In an alarm system including an alarm circuit and alarm sensing means the state of which is changeable between a non-alarm condition and an alarm condition, the improvement comprising pulsing means connected to said alarm sensing means for generating a substantially constant voltage in said non-alarm condition and a pulsating voltage in said alarm condition of said alarm sensing means;
- switch means for enabling and disabling the alarm circuit and for providing higher and lower reference voltage as a function of the enabled and disabled conditions of the alarm circuit; and
indicating means connected between said pulsing and switching means and adapted to permit current flow in each of two opposite directions therethrough as a function of the relative voltages provided by both said pulsating and switching means across said indicating means, said indicating means providing a different indication for each of the two directions of current flow therethrough, whereby a total of at least four indications may be obtained by selective passage of currents through said indicating means which currents may flow in one of said two opposing directions and which may be zero, constant or pulsed in each of said directions to thereby provide said indications in either constant or in pulsed form. - View Dependent Claims (2, 3, 4, 5, 6)
- switch means for enabling and disabling the alarm circuit and for providing higher and lower reference voltage as a function of the enabled and disabled conditions of the alarm circuit; and
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7. In an alarm system including an alarm circuit and alarm sensing means the state of which is changeable between a non-alarm condition and an alarm condition, the improvement comprising pulsing means connected to said alarm sensing means for generating a substantially constant voltage in said non-alarm condition and a pulsating voltage in said alarm condition of said alarm sensing means;
- first switch means for enabling and disabling the alarm circuit and for providing higher and lower reference voltages as a function of the enabled and disabled conditions of the alarm circuit;
indicating means connected by means of two leads between said pulsing and first switching means and adapted to permit current flow in each of two opposite directions therethrough as a function of the relative voltages provided by both said pulsating and first switching means across said indicating means, said indicating means providing a different indication for each of the two directions of current flow therethrough; and
second switch means connected by means of a third lead to said first switch means and further connected to one of said leads connecting said indicating means to said pulsing means for controlling the condition of said first switch means, whereby said indicating means and said second switch means are connected to said pulsing and first switch means by three leads and whereby a total of at least four indications may be obtained by selective passage of currents through said indicating means which currents may be zero, flow in one of said two opposing directions and which may be constant or pulsed in each of said directions to thereby provide said indications in constant or in pulsed form. - View Dependent Claims (8, 9, 10, 11, 12, 13)
- first switch means for enabling and disabling the alarm circuit and for providing higher and lower reference voltages as a function of the enabled and disabled conditions of the alarm circuit;
Specification