GB763586A - Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes - Google Patents

Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes

Info

Publication number
GB763586A
GB763586A GB21490/52A GB2149052A GB763586A GB 763586 A GB763586 A GB 763586A GB 21490/52 A GB21490/52 A GB 21490/52A GB 2149052 A GB2149052 A GB 2149052A GB 763586 A GB763586 A GB 763586A
Authority
GB
United Kingdom
Prior art keywords
plate
secured
magnets
magnet
tube neck
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
GB21490/52A
Inventor
Guy Birkbeck
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.)
Mullard Radio Valve Co Ltd
Original Assignee
Mullard Radio Valve Co 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
Priority to BE522315D priority Critical patent/BE522315A/xx
Application filed by Mullard Radio Valve Co Ltd filed Critical Mullard Radio Valve Co Ltd
Priority to GB21490/52A priority patent/GB763586A/en
Priority to US375782A priority patent/US2740064A/en
Priority to DEN7628A priority patent/DE972501C/en
Priority to FR1090512D priority patent/FR1090512A/en
Publication of GB763586A publication Critical patent/GB763586A/en
Expired legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/46Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
    • H01J29/58Arrangements for focusing or reflecting ray or beam
    • H01J29/64Magnetic lenses
    • H01J29/68Magnetic lenses using permanent magnets only

Landscapes

  • Video Image Reproduction Devices For Color Tv Systems (AREA)
  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)

Abstract

763,586. Cathode-ray tubes. MULLARD RADIO VALVE CO., Ltd. July 31, 1953 [Aug. 26, 1952], No. 21490/52. Class 39(1). A permanent magnet focussing mount for the cathode ray tube of a television receiver or like apparatus comprises a main support member 1 in the form of a metal plate provided with an aperture for the tube neck and having its edges bent over to increase the longitudinal rigidity and carrying guide rods 2 and 3 to which an apertured plate 4 is attached. An annular magnet 6 is secured to the plate 4 by means of three tabs 5 formed in the edge of the plate. A second annular magnet 7 is secured by tabs 8 to an apertured plate 9 secured to a tubular guide 10 which slides on the rod 2 and having two guide flanges 11 which lie on either side of the rod 3. Movement of the magnet 7 towards the magnet 6 is effected by a lever 13 fulcrummed on the plate 1 as by a pivot pin 14 and having a forked end bent to engage the back of the plate 9. The end 15 of the lever 13 is moved towards the plate 1 by any suitable means, for example a Bowden cable, so that the focus control can be brought to any convenient point of the receiver cabinet. The polarity of the magnets is such that they tend to repel one another, so no return spring is necessary. The assembly is correctly located with respect to the tube neck by a device, Fig. 3, of the " iris " type, comprising a circular plate 19 mounted on pins 16, 17 and 18 secured to the plate 1 and passing through three arcuate slots in the plate 19. Each pin forms a fulcrum for an arcuate lever 20 carrying a pin 21, which engages the wall of a hexagonal aperture in the plate 19, and a pad 22 of felt, rubber or the like. The plate 19 is urged in the direction to cause closure of the pads 22 on the tube neck by a spring 23 secured between the plate 19 and the plate 1. The magnets 6 and 7 are located in correct coaxial relationship during assembly of the apparatus by means of a mandrel having an end portion of the same diameter as the tube neck and a further portion of larger diameter on which the magnets are located. The mandrel is placed in position with one end gripped by the pads 22 and the other end located in the aperture in the plate 4, whereupon the tabs 8 and 9 are bent up to lock the magnets in position and the mandrel then removed.
GB21490/52A 1952-08-26 1952-08-26 Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes Expired GB763586A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
BE522315D BE522315A (en) 1952-08-26
GB21490/52A GB763586A (en) 1952-08-26 1952-08-26 Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes
US375782A US2740064A (en) 1952-08-26 1953-08-21 Permanent magnet focussing device for cathode ray tubes
DEN7628A DE972501C (en) 1952-08-26 1953-08-25 Permanent magnetic focusing device for the cathode ray tube of a television receiver
FR1090512D FR1090512A (en) 1952-08-26 1953-08-26 Magnetic concentration device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB21490/52A GB763586A (en) 1952-08-26 1952-08-26 Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes

Publications (1)

Publication Number Publication Date
GB763586A true GB763586A (en) 1956-12-12

Family

ID=10163820

Family Applications (1)

Application Number Title Priority Date Filing Date
GB21490/52A Expired GB763586A (en) 1952-08-26 1952-08-26 Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes

Country Status (5)

Country Link
US (1) US2740064A (en)
BE (1) BE522315A (en)
DE (1) DE972501C (en)
FR (1) FR1090512A (en)
GB (1) GB763586A (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2820917A (en) * 1954-02-23 1958-01-21 Sprague Electric Co Focussing device
NL199308A (en) * 1954-08-04
NL86361C (en) * 1954-12-04
US3098942A (en) * 1955-02-24 1963-07-23 Zenith Radio Corp Magnetic centering device for cathode ray tubes
US2985788A (en) * 1956-01-19 1961-05-23 Westinghouse Electric Corp Spark gap device

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2418487A (en) * 1944-03-31 1947-04-08 Bell Telephone Labor Inc Cathode ray magnetic focusing device
US2443973A (en) * 1945-01-05 1948-06-22 Avco Mfg Corp Control device for cathode-ray focusing coils
BE487122A (en) * 1948-02-07
US2569327A (en) * 1948-08-31 1951-09-25 Rca Corp Electron beam bender
GB670021A (en) * 1949-02-18 1952-04-09 Patrick Richard James Court Improvements in beam centering devices for cathode ray tubes
US2580606A (en) * 1951-03-21 1952-01-01 Best Mfg Company Inc Cathode-ray tube focusing device

Also Published As

Publication number Publication date
DE972501C (en) 1959-08-20
FR1090512A (en) 1955-03-31
US2740064A (en) 1956-03-27
BE522315A (en)

Similar Documents

Publication Publication Date Title
GB763586A (en) Improvements in or relating to permanent magnet focussing arrangements for cathode ray tubes
US2766393A (en) Color television receiver
GB615553A (en) Improvements in or relating to devices for focusing an electron beam
US2634381A (en) Cathode-ray tube beam-positioning device
US2592185A (en) Focusing device
US2500623A (en) Cathode-ray device
GB691156A (en) Improvements in or relating to corpuscular ray apparatus
US2972074A (en) Magnetic beam-controlling means for cathode ray tubes
US2635204A (en) Cathode-ray tube beam-centering device
US2640868A (en) Magnetic focusing device for cathode-ray tubes
GB735512A (en) Improvements in and relating to cathode ray tube apparatus
GB766158A (en) A beam generating system for cathode-ray tubes employing an ion trap
US2579941A (en) Cathode-ray tube
GB830075A (en) Improvements in or relating to cathode ray tubes
GB455200A (en) Improvements in or relating to deflecting means for cathode-ray tubes
GB720662A (en) Improvements in or relating to permanent magnet electron lenses
GB745009A (en) Improvements in or relating to cathode ray tube apparatus
GB1086095A (en) Improvements in or relating to devices for correcting the picture geometry of cathode ray tubes
GB731451A (en) Improvements in or relating to arrangements for use with cathode ray tubes
US3521206A (en) Holding devices for centering magnets of cathode ray tubes
GB425493A (en) Improvements in or relating to electric discharge devices
GB618552A (en) Improvements in and relating to cathode ray apparatus
US2788468A (en) Cathode ray tubes
GB855989A (en) Improvements relating to electron-optical devices
GB742789A (en) Improvements in or relating to television receivers