Electrical Potential Indicator (Patent No: 595486)

Inventor: DeMott, Robert E.

Location: Delia

Comments: N/A

Description: The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
(1) An electrical potential indicator adapted to be used in circuit with a force of electrical energy and an electrical device; comprising in combination a heat generating impedance element parallel with said electrical device and heat responsive means adapted to be activated by said impedance when said electrical device is disconnected from said source of electrical energy.
(2) The device according to Claim 1 in which said means includes a heat responsive color change substance.
(3) The device according to Claim 1 in which said means includes a fusible and visible deposit forming substance.
(4) In an incandescent electric tube including a filament, an electric potential indicator in parallel with said filament, said indicator including a heat generating impedance element in parallel with said filament and means activated by a predetermined temperature attained by said impedance thereby indicating an increase in potential through said impedance.
(5) The device according to Claim 4 in which said means includes a heat responsive color change substance.
(6) The device according to Claim 4 in which said means includes a fusible and visible deposit forming substance.
(7) The device according to Claim 5 in which is included an envelope sealably secured to said electric tube, said impedance and said means being contained within said envelope.
(8) The device according to Claim 5 in which is included an evacuated envelope sealably secured to said electric tube, said impedance and said means being contained within said evacuated envelope.
(9) The device according to Claims 7 or 8 in which is included a wafer extended within said envelope, said heat responsive color change substance being supported by said wafer.
(10) The device according to Claims 7 or 8 which includes a wafer extended within said envelope, said heat generating impedance element being supported by said wafer, said fusible and visible deposit forming substances also being supported by said wafer.
(11) The device according to Claim 4 in which said indicator is situated adjacent the base of said tube and visible therethrough.
(12) The device according to Claim 4 which includes an insulated stem extending upwardly within said envelope, said indicator being supported upon the upper end of said stem.
(13) An electrical potential indicator to be used in circuits with a force of electrical energy and an incandescent electric tube including a filament; comprising in combination a separate evacuated and sealed envelope secured to said tube and including an indicator filament in parallel with, and having a longer operating life and operating at a lower temperature than said electric tub filament thereby indicating the approximate amount of potential across said electric tube.