GB637336A - Improvements in or relating to apparatus for detecting and/or locating by electrical means masses of electrically conducting or magnetic material - Google Patents

Improvements in or relating to apparatus for detecting and/or locating by electrical means masses of electrically conducting or magnetic material

Info

Publication number
GB637336A
GB637336A GB28182/47A GB2818247A GB637336A GB 637336 A GB637336 A GB 637336A GB 28182/47 A GB28182/47 A GB 28182/47A GB 2818247 A GB2818247 A GB 2818247A GB 637336 A GB637336 A GB 637336A
Authority
GB
United Kingdom
Prior art keywords
valve
oscillator
voltage
changes
pick
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB28182/47A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cinema Television Ltd
Original Assignee
Cinema Television Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cinema Television Ltd filed Critical Cinema Television Ltd
Priority to GB28182/47A priority Critical patent/GB637336A/en
Priority to FR972618D priority patent/FR972618A/en
Priority to CH308309D priority patent/CH308309A/en
Publication of GB637336A publication Critical patent/GB637336A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
    • G01V3/08—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices
    • G01V3/10—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils
    • G01V3/104—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils using several coupled or uncoupled coils
    • G01V3/105—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils using several coupled or uncoupled coils forming directly coupled primary and secondary coils or loops
    • G01V3/107—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils using several coupled or uncoupled coils forming directly coupled primary and secondary coils or loops using compensating coil or loop arrangements

Abstract

637,336. Locating conductors. CINEMATELEVISION, Ltd., and LOGAN, S. Y. Oct. 21, 1947, No. 28182. [Class 37] Apparatus for locating conductors of the type comprising a search head 2 with two coils, one from an oscillator 1 and the other acting as a pick-up coil, preferably not inductively coupled, is characterized in that a proportion of the oscillator voltage is fed into two valves 11, 12 of a detector, the first valve also being fed with the pick-up voltage, so that the detector is not affected by changes in oscillator output. Valves 11, 12 are fed through rectifiers 6, 9, the anode voltages being taken to the grids of a double triode valve 17 through R.C. couplings whose time constants are such that slow changes of anode voltage are ignored, and rapid changes (e.g. 3 volts per second) such as caused by pick-up due to the proximity of a conductor produce changes in the anode currents of the respective sections of valve 17 to operate a relay 18 connected between the anodes of the two sections of valve 17. The response of the relay 18 is affected by the phase angle of the voltage induced in the pickup coil. The outputs of the oscillator 1 and amplifier 4 are preferably stabilized.
GB28182/47A 1947-10-21 1947-10-21 Improvements in or relating to apparatus for detecting and/or locating by electrical means masses of electrically conducting or magnetic material Expired GB637336A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
GB28182/47A GB637336A (en) 1947-10-21 1947-10-21 Improvements in or relating to apparatus for detecting and/or locating by electrical means masses of electrically conducting or magnetic material
FR972618D FR972618A (en) 1947-10-21 1948-10-01 Improvements in electrical detection and identification devices for electrically conductive or magnetic masses
CH308309D CH308309A (en) 1947-10-21 1948-10-13 Electrical apparatus for searching for masses of magnetic materials and electrically conductive materials.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB28182/47A GB637336A (en) 1947-10-21 1947-10-21 Improvements in or relating to apparatus for detecting and/or locating by electrical means masses of electrically conducting or magnetic material

Publications (1)

Publication Number Publication Date
GB637336A true GB637336A (en) 1950-05-17

Family

ID=10271573

Family Applications (1)

Application Number Title Priority Date Filing Date
GB28182/47A Expired GB637336A (en) 1947-10-21 1947-10-21 Improvements in or relating to apparatus for detecting and/or locating by electrical means masses of electrically conducting or magnetic material

Country Status (3)

Country Link
CH (1) CH308309A (en)
FR (1) FR972618A (en)
GB (1) GB637336A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2545218A1 (en) * 1983-04-27 1984-11-02 Pall Corp ELECTROMAGNETIC DETECTOR FOR METALLIC MATERIALS
US4709213A (en) * 1982-07-23 1987-11-24 Garrett Electronics, Inc. Metal detector having digital signal processing

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4709213A (en) * 1982-07-23 1987-11-24 Garrett Electronics, Inc. Metal detector having digital signal processing
FR2545218A1 (en) * 1983-04-27 1984-11-02 Pall Corp ELECTROMAGNETIC DETECTOR FOR METALLIC MATERIALS
EP0124042A2 (en) * 1983-04-27 1984-11-07 Pall Corporation Electromagnetic detector for metallic materials
EP0124042A3 (en) * 1983-04-27 1985-01-09 Pall Corporation Electromagnetic detector for metallic materials
US4613815A (en) * 1983-04-27 1986-09-23 Pall Corporation Electromagnetic detector for metallic materials having an improved phase detection circuit

Also Published As

Publication number Publication date
FR972618A (en) 1951-02-01
CH308309A (en) 1955-07-15

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