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US3789294A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for measuring insulating and voltage resistant characteristics of articles

Assignee: Chubu Seiki Co Ltd
•
Filing: 1972-07-19
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Granted: 1974-01-29
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Expires: 1992-07-19
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Abstract

Abstract Device for measuring insulating and voltage resistant characteristics of articles such as a high voltage cable wherein a low battery voltage in converted into a high direct current voltage with the aid of successive stages of oscillator, transformer and rectifier circuits whose output is applied across an article to be measured. The input bias of a transistor is changed in a manner such that the output of the circuits is made a given value whereby the insulating and voltage resistant characteristics of the article are measured by observing the indication of a voltmeter and ammeter.

Inventors

  • 👤 H Nitta
  • 👤 M Kaneko

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 04:53
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01R27/025

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 180 words
A portable device for measuring insulating and voltage resistant characteristics of an article to be measured by a high direct current voltage comprising, an oscillator circuit operated by an electric source and including an oscillator transformer which has a primary winding connected between collector and emitting electrodes of a transistor, a secondary winding having one end connected to a base electrode of said transistor and the other end connected to the emitter electrode of said transistor through a condenser and a tertiary winding for generating a high alterminating current voltage, a high voltage direct current generating circuit means connected to said tertiary winding to convert the high voltage alternating current output into a high voltage direct current which is applied to said article to be measured, and a discharging circuit means including a relay energized by said electric source when operating said oscillator circuit and having a contact for connecting the output of said direct current operating circuit means to ground to discharge an electric charge accumulated on said article when the electric source to said oscillator circuit is disconnected.
Claim 2
Dependent Claim 180 words
A portable device for measuring insulating and voltage resistant characteristics of an article to be measured by a high direct current voltage comprising, an oscillator circuit operated by an electric source and including an oscillator transformer which has a primary winding connected between collector and emitting electrodes of a transistor, a secondary winding having one end connected to a base electrode of said transistor and the other end connected to the emitter electrode of said transistor through a condenser and a tertiary winding for generating a high alterminating current voltage, a high voltage direct current generating circuit means connected to said tertiary winding to convert the high voltage alternating current output into a high voltage direct current which is applied to said article to be measured, and a discharging circuit means including a relay energized by said electric source when operating said oscillator circuit and having a contact for connecting the output of said direct current operating circuit means to ground to discharge an electric charge accumulated on said article when the electric source to said oscillator circuit is disconnected.
Claim 3
Dependent Claim 48 words
A portable device according to claim 1 wherein said electric source is a storage battery which is connected to the base electrode of transistor through a variable resistor for controlling the output of said oscillator circuit by varying the voltage impressed to the base electrode of said transistor.
Claim 4
Dependent Claim 49 words
A portable device according to claim 1 wherein a voltmeter is connected in parallel to the output of said high voltage direct current generating circuit means and an ammeter is connected in series to the output of said high voltage direct current generating circuit means for detecting leakage current.

References Cited (Backward Citations)

US2920270A Cited
US3042861A Cited
US3071724A Cited
US3259893A Cited
US3339136A Cited
US3321703A Cited
US3354387A Cited
US3652932A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-01-28 1977-07-30 1978-01-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-01-28 1981-07-30 1982-01-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-01-28 1985-07-30 1986-01-29 $7700.00 Window Closed / Lapsed

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