# US 6,215,239 B1 · CRT deflection unit having a cooling fin > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,215,239 B1 - Document ID: US6215239B1 - Status: Granted - Kind: B1 - Application number: 09/391,815 - Filed: 1999-09-08 - Granted: 2001-04-10 - Earliest claimed: 1998-09-11 - Assignees: U.S. Philips Corporation - Inventors: Martinus H. E. Jansen; Arnoldus M. C. Kieboom - Web page: https://patentgrep.com/patent/US6215239B1 ## CPC - H01J 29/76: Deflecting by magnetic fields only - H01J 2229/0092: Passive means, e.g. fins, heat conductors - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract A cathode ray tube includes a deflection unit (11) having a cooling fin (25) which is attached to the surface of a tapering surface on a yoke ring (23) by lugs (27). At least one of the lugs has a free end extending axially and outwardly in thermal contact with the tapering surface, and at least another of the lugs has a free end extending axially in an opposite direction and inwardly in thermal contact with the tapering surface. ## Claims ### Claim 1 A cathode ray tube (1) comprising means (6) for generating at least one electron beam, a display screen (2), a deflection unit (11) having coils (21, 22) for deflecting the electron beam(s) across the display screen (2), and a yoke ring (23) which surrounds at least one of the coils (21, 22), said yoke ring (23) being provided with at least one cooling fin (25) for dissipating heat generated by the coils (21, 22), said cooling fin (25) thermally contacting the yoke ring by means of a plurality of lugs (27) which contact a surface of the yoke ring (23), characterized in that at least one of the lugs (27) of the cooling fin (25) is arranged so as to face the display screen (2) with a thermally contacting surface free end, and at least another of the lugs (27) is arranged so as to face away from the display screen (2) with a thermally contacting surface free end. ### Claim 2 (depends on 1) A cathode ray tube (1) as claimed in claim 1, characterized in that the lugs (27) are arranged in groups of three and, within a group, the central lug (27) points with its free end in a direction which is opposite to the direction in which the outermost lugs (27) point with their free ends. ### Claim 3 (depends on 2) A cathode ray tube as claimed in claim 2, characterized in that the central lug (27) faces the display screen (10) with its free end, and the two outer lugs (27) face away from the display screen (10) with their free end. ### Claim 4 (depends on 1) A cathode ray tube (1) as claimed in claim 1, characterized in that the cooling fin (25) is ring-shaped and provided with a circularly-symmetrical ridge (29), which is situated between the lugs (27) and an outer circumference of the cooling fin (25). ### Claim 5 (depends on 1) A cathode ray tube (1) as claimed in claim 1, characterized in that the cooling fin (25) is provided with grooves (31) extending in a radial direction. ### Claim 6 A cathode ray tube (1) comprising means (6) for generating at least one electron beam, a display screen (2), a deflection unit (11) having coils (21, 22) for deflecting the electron beam(s) across the display screen (2), and a yoke ring (23) which surrounds at least one of the coils (21, 22), said yoke ring (23) having an axially extending external surface tapering outwardly toward the display screen and being provided with at least one cooling fin (25) for dissipating heat generated by the coils (21, 22), said cooling fin (25) thermally contacting said surface by means of a plurality of lugs (27), characterized in that at least one of the lugs (27) is arranged with a free end extending axially toward the display screen (2) and outwardly to be in thermal contact with said surface, and at least another of the lugs (27) is arranged with a respective free end extending axially away from the display screen (2) and inwardly to be in thermal contact with said surface. ### Claim 7 (depends on 6) A cathode ray tube (1) as claimed in claim 6, characterized in that the cooling fin (25) is provided with radial slits (31) extending between said lugs to an outer circumferential portion free from said slits. ### Claim 8 (depends on 6) A cathode ray tube (1) as claimed in claim 6, characterized in that the lugs (27) are arranged in groups of three and, within a group, a central lug (27) points with its free end in a direction which is opposite to the direction in which the outermost lugs (27) point with their free ends. ### Claim 9 (depends on 8) A cathode ray tube (1) as claimed in claim 8, characterized in that the central lug (27) faces the display screen (10) with its free end, and the two outer lugs (27) face away from the display screen (10) with their free end. ### Claim 10 (depends on 6) A cathode ray tube (1) as claimed in claim 6, characterized in that the cooling fin (25) is ring-shaped and provided with a circularly-symmetrical ridge (29), which is situated between the lugs (27) and an outer circumference of the cooling fin (25). ### Claim 11 (depends on 10) A cathode ray tube (1) as claimed in claim 10, characterized in that the cooling fin (25) is provided with radial slits (31) extending between said lugs and through said ridge, and said outer circumferential portion is free from said slits. ### Claim 12 A cooling fin (25) for dissipating heat from an object having a tapering surface, comprising: a substantially planar circumferential portion, and a plurality of lugs (27) for contacting the tapering surface of the object, characterized in that at least one of the lugs (27) of the cooling fin (25) is arranged with a free end extending axially in a first direction and outwardly to be in thermal contact with said tapering surface, and at least another of the lugs (27) is arranged with a respective free end extending axially in a direction opposite to said first direction and inwardly to be in thermal contact with said surface. ### Claim 13 (depends on 12) A cooling fin (25) as claimed in claim 12, characterized in that the cooling fin (25) is provided with radial slits (31) extending between said lugs to an outer portion of said circumferential portion free from said slits. ### Claim 14 (depends on 12) A cooling fin (25) as claimed in claim 12, characterized in that the lugs (27) are arranged in groups of three and, within a group, the central lug (27) points with its free end in a direction which is opposite to the direction in which the outermost lugs (27) point with their free ends. ### Claim 15 (depends on 12) A cooling fin (25) as claimed in claim 12, characterized in that the cooling fin (25) is ring-shaped and provided with a circularly-symmetrical ridge (29), which is situated between the lugs (27) and said substantially planar circumferential portion. ### Claim 16 (depends on 15) A cooling fin (25) as claimed in claim 15, characterized in that the cooling fin (25) is provided with radial slits (31) extending between said lugs and through said ridge, and said substantially planar circumferential portion is free from said slits.