EP0004245B1 - Bildröhre mit einer Lochschattenmaske für Farbfernsehen - Google Patents

Bildröhre mit einer Lochschattenmaske für Farbfernsehen Download PDF

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Publication number
EP0004245B1
EP0004245B1 EP79400158A EP79400158A EP0004245B1 EP 0004245 B1 EP0004245 B1 EP 0004245B1 EP 79400158 A EP79400158 A EP 79400158A EP 79400158 A EP79400158 A EP 79400158A EP 0004245 B1 EP0004245 B1 EP 0004245B1
Authority
EP
European Patent Office
Prior art keywords
frame
mask
skirt
bosses
tube
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
EP79400158A
Other languages
English (en)
French (fr)
Other versions
EP0004245A1 (de
Inventor
Ignazio Cormio
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.)
Videocolor SA
Original Assignee
Videocolor SA
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 Videocolor SA filed Critical Videocolor SA
Publication of EP0004245A1 publication Critical patent/EP0004245A1/de
Application granted granted Critical
Publication of EP0004245B1 publication Critical patent/EP0004245B1/de
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
    • H01J29/06—Screens for shielding; Masks interposed in the electron stream
    • H01J29/07—Shadow masks for colour television tubes
    • H01J29/073—Mounting arrangements associated with shadow masks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J31/00—Cathode ray tubes; Electron beam tubes
    • H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
    • H01J31/10—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes
    • H01J31/20—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes for displaying images or patterns in two or more colours
    • H01J31/201—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes for displaying images or patterns in two or more colours using a colour-selection electrode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2229/00—Details of cathode ray tubes or electron beam tubes
    • H01J2229/07—Shadow masks
    • H01J2229/0716—Mounting arrangements of aperture plate to frame or vessel
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2229/00—Details of cathode ray tubes or electron beam tubes
    • H01J2229/07—Shadow masks
    • H01J2229/0722—Frame
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2229/00—Details of cathode ray tubes or electron beam tubes
    • H01J2229/07—Shadow masks
    • H01J2229/0727—Aperture plate
    • H01J2229/0766—Details of skirt or border
    • H01J2229/0772—Apertures, cut-outs, depressions, or the like

Definitions

  • the invention relates to a cathode ray tube of the mask type for viewing, in particular television, in color.
  • color television tubes have, in the vicinity of the panel, that is to say of the front part of the tube on which the phosphors are deposited, a mask constituted for example by a metal plate or grid of about 1 / 10th of a mm thick with a network of openings, elongated or not. Opposite each of these openings are three zones, small areas, of the phosphor layer; these zones take, when they are excited, the colors, respectively, green, red and blue.
  • the relative positions of the electron guns, the openings of the mask and the zones of the phosphor layer as well as the means for controlling the beams generated by the guns are such that each of the electron guns can only excite phosphors of one color. determined.
  • the invention aims to eliminate the drawbacks of the prior art and to further reduce the effects of variations in mask temperature during the heating period of the tube on its position relative to the slab.
  • Another object of the invention is to allow a particularly simple and economical production of a mask tube for color television.
  • a cathode ray tube comprising a screen panel at the front of the tube, a mask having a perforated surface, mounted immediately behind the screen and bordered by a peripheral skirt, a rigid mask support frame, attached to the slab and comprising a wall substantially parallel to the axis of the tube, along which the peripheral skirt of the mask is fixed by welding points in a limited number of contact zones separated by intervals in which is formed a space between the skirt of the mask and the wall of the frame, is characterized in that said wall of the frame has on its internal face a plurality of bosses spaced from each other and in that the skirt of the mask is in abutment against each of these bosses inside said frame and joined to at least some of these bosses by a respective welding point.
  • the profile of the mask skirt bearing against the bosses is a regular profile.
  • bosses of the frame increase its mechanical rigidity. It is thus possible to use a support frame which is easier to fix than in the prior art and the mounting of the mask inside the frame increases the compactness of the assembly.
  • the invention also relates to a frame and a mask for cathode ray tube.
  • the color television tube partially shown in the figures has a front part or slab 1 ( Figure 4) on the inner face 1 a of which is deposited the phosphor layer of the tube.
  • This slab 1 has a flange 2 for its connection with the conical rear part (not shown) of the tube.
  • mask 3 is arranged, which is constituted by a thin metal plate, the thickness of which is of the order of 1 / 10th of a mm, which is pierced with a network of holes (not shown). and which has a rim 3a fixed to a profiled metal frame 4 having the general shape of a square with two branches 5 and 6.
  • the rim 3a is fixed on the internal face (that is to say the face which is turned towards the space delimited by the frame) of branch 6 of this frame.
  • Fixing means 7 are provided for assembling the frame, and therefore the mask, to the rim 2 of the slab 1.
  • the internal face of the branch 6 of the frame 4 has bosses 8, 9, etc. ( Figure 1) arranged at a distance from each other, regularly around the periphery of the frame.
  • the bosses have a generally rectangular shape and are formed by pushing back the branch 6 of the frame 4.
  • bosses 8, 9 occupy only part of the width of the branch 6 ( Figure 2), that which is closest to the branch 5.
  • the branch 6 thus has a half-width 6a, at near its free edge 6b, which is devoid of bosses and is spaced from the rim 3a.
  • FIG. 3 schematically, the general shape of the rim 3a of the mask 3, with - shown in the form of a cross - the points of attachment of this rim 3a to the branch 6 of the frame 4.
  • Other fixing points 15, 16, 17 and 18 are also provided in the vicinity of the median axes (mediators) 19 and 20 on the sides of the rectangle formed by the rim 3a.
  • these latter attachment points are not exactly located on these axes 19 and 20 but are slightly offset from the latter and, moreover, they are not on the same side with respect to this axis.
  • the fixing point 15 is located to the right (in FIG.
  • the distance separating point 15 from axis 20 is of the order of 6 mm; point 16 is at the same distance from this axis 20.
  • Points 17 and 18 are arranged approximately 10 mm from axis 19.
  • points 11, 11 a and 21, 21 a are each approximately 130 mm from axis 20.
  • bosses improve the mechanical rigidity of the frame 4.
  • the frame 4 has pairs of tongues 23 and 24 formed by cutouts in the branch 5 which are folded down to form an extension of the branch 6, opposite to the branch 5.
  • the tongue 24 has two branches 25 and 26 separated by a slot 27. These branches 25 and 26 are in planes offset with respect to each other, so that the front face of the branch 25 is substantially at the same level as the rear face from branch 26, so that the end 29 of a fixing lug 28 can be interposed between this rear face of the branch 26 and the front face of the branch 25.
  • the end 29 of the lug 28 is, moreover, welded to the rear face of the branch 26.
  • the tab 28 is also welded to the rear face of the tongue 23 and the other end 30 of this tab 28 is fixed, by means of a button 31, to the flange 2 of the slab 1.
  • the tab 28 has two parts lying in parallel planes.
  • the part 28a, terminated by the end 30, is applied against the internal face of the rim 2 of the slab while, as we have seen above, the part 28b, terminated by the end 29, is applied, by weld points, against the tongues 23 and 26.
  • the tab 28 is a simple metal blade without special provisions to compensate for possible deformations caused by temperature variations, these deformations being, as already mentioned, compensated by the presence of the bosses of the branch 6 of the frame 4.
  • the number of welding points from the rim of the mask to the frame is at least equal to four, these four welding points being arranged in the vicinity of the vertices of the rectangle formed by this rim.
  • the number of welding points is higher.

Landscapes

  • Electrodes For Cathode-Ray Tubes (AREA)

Claims (9)

1. Kathodenstrahlröhre mit einer Maske, insbesondere für ein Farbfernsehgerät, welche folgende Bauteile umfasst: Eine an der Vorderseite der Röhre angeordnete Schirmplatte (1), eine unmittelbar hinter dem Schirm (1) angeordnete und mit einem umfänglichen Schurzteil (3a) versehene perforierte Maske (3), einen steifen Maskenhalterrahmen (4), der auf die Platte (1) montiert ist und eine zur Röhrenachse wesentlich parallele Wandung (6) aufweist, längs welcher der umfängliche Schurzteil der Maske durch Schweisspunkte (10, 11, usw.) in einer beschränkten Anzahl von Kontaktzonen befestigt ist, die durch Zwischenräume getrennt sind, in denen ein freier Raum zwischen dem Schurzteil (3a), der Maske und der Wandung (6) des Rahmens gebildet wird, dadurch gekennzeichnet, dass die Rahmenwandung an ihrer Innenseite eine Mehrzahl von mit gegenseitigem Abstand angeordneten Höckern (8, 9) aufweist, und dass der Schurzteil (3a) der Maske (3) sich an jedem dieser Höcker (9) innerhalb des Rahmens (4) abstützt und wenigstens mit einigen der Höcker jeweils durch einen Schweisspunkt verbunden ist (10, 11 usw.).
2. Röhre nach Anspruch 1, dadurch gekennzeichnet, dass das sich an den Höckern abstützende Profil des Maskenschurzteiles (3a) ein regelmässiges Profil ist.
9. Röhre nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der Maskenschurzteil (3a) ein der perforierten Fläche der Maske (3) benachbarte un ausser jeglicher Berührung mit dem Rahmen (4) stehende ununterbrochene Umfangszone aufweist.
4. Röhre nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass die Höcker (8, 9) eine Höhe besitzen, die kleiner ist, als die axiale Abmessung der Wandung (6) des Rahmens (4) und derart in Richtung zur Rückseite dieses Rahmens versetzt sind, dass vor jedem Höcker ein freier Raum zwischen der Wandung (6a) des Rahmens und einem gegenüberliegenden, der perforierten Fläche der Maske (3) benachbarten Teil des Maskenschurzteiles (3a) gebildet wird.
5. Röhre nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Schweisspunkte (10, 11 usw.), die den Schurzteil (3a) mit den Höckern (8, 9) verbinden, höchstens 3 mm vom freien Rand (3b) des Schurzteiles entfernt sind.
6. Röhre nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Höhe eines Höckers (8, 9) wenigstens 1,4 mm beträgt.
7. Röhre nach einem der vorstehenden Ansprüche, bei welcher der Rahmen (4) eine im Wesentlichen etwa rechteckige Form besitzt, dadurch gekennzeichnet, dass der Schurzteil der Maske wenigstens in vier, den Mittelachsen (19, 20) des Rahmens (4) benachbarten Zonen an diesem Rahmen befestigt ist, wobei die beiden Befestigungszonen (15, 16; 17, 18) in bezug auf diese Achse beiderseitig versetzt sind.
8. Rahmen für eine Kathodenstrahlröhre für ein Sehgerät, wie Farbfernsehgerät, dadurch gekennzeichnet, dass er Höcker (8, 9) geringen Querschnitts besitzt, die längs des Rahmenumfangs mit gegenseitigem Abstand und an der Innenseite der Rahmenwandung (6) angeordnet sind.
9. Rahmen nach Anspruch 8, dadurch gekennzeichnet, dass die Höcker (7, 8) nur über einen Teil der Breite des Rahmens verteilt sind.
EP79400158A 1978-03-13 1979-03-09 Bildröhre mit einer Lochschattenmaske für Farbfernsehen Expired EP0004245B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7807191 1978-03-13
FR7807191A FR2420205A1 (fr) 1978-03-13 1978-03-13 Tube a masque pour la television en couleurs

Publications (2)

Publication Number Publication Date
EP0004245A1 EP0004245A1 (de) 1979-09-19
EP0004245B1 true EP0004245B1 (de) 1983-09-28

Family

ID=9205701

Family Applications (1)

Application Number Title Priority Date Filing Date
EP79400158A Expired EP0004245B1 (de) 1978-03-13 1979-03-09 Bildröhre mit einer Lochschattenmaske für Farbfernsehen

Country Status (5)

Country Link
US (1) US4308485A (de)
EP (1) EP0004245B1 (de)
JP (1) JPS54127276A (de)
DE (1) DE2966214D1 (de)
FR (1) FR2420205A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3919674A1 (de) * 1989-06-16 1990-12-20 Nokia Unterhaltungselektronik Masken-rahmen-kombination fuer eine farbbildroehre

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3115799C2 (de) * 1981-04-18 1985-05-30 Standard Elektrik Lorenz Ag, 7000 Stuttgart Farbauswahlelektrode für Farbfernsehröhren und Verfahren zu ihrer Herstellung
FR2555808B1 (fr) * 1983-11-25 1986-10-10 Videocolor Masque d'ombre pour tube d'image en couleurs et tube d'image le comportant
JPS60130032A (ja) * 1983-12-15 1985-07-11 Matsushita Electric Ind Co Ltd カラ−受像管用シヤドウマスク
JPS6253554U (de) * 1985-09-25 1987-04-02
US4935346A (en) 1986-08-13 1990-06-19 Lifescan, Inc. Minimum procedure system for the determination of analytes
NL8603055A (nl) * 1986-12-01 1988-07-01 Philips Nv Kleurenbeeldbuis omvattende een nagenoeg rechthoekig draagraam waaraan een schaduwmasker is bevestigd.
US5218265A (en) * 1989-06-16 1993-06-08 Nokia (Deutschland) Gmbh Combined mask-frame with double spot welds
TW328605B (en) * 1996-03-11 1998-03-21 Hitachi Ltd The color cathode tube
US6188170B1 (en) 1996-07-12 2001-02-13 Kabushiki Kaisha Toshiba Color cathode ray tube including mask frame with protruding portions
DE69709257T2 (de) * 1996-07-12 2002-08-14 Kabushiki Kaisha Toshiba, Kawasaki Farbkathodenstrahlröhre
WO1998012729A1 (en) * 1996-09-17 1998-03-26 Hitachi, Ltd. Color cathode-ray tube
TW423010B (en) * 1997-05-20 2001-02-21 Toshiba Corp Color cathode ray tube
US6373176B1 (en) 1998-08-21 2002-04-16 Pixtech, Inc. Display device with improved grid structure
US6458326B1 (en) 1999-11-24 2002-10-01 Home Diagnostics, Inc. Protective test strip platform
US6525330B2 (en) 2001-02-28 2003-02-25 Home Diagnostics, Inc. Method of strip insertion detection
US6541266B2 (en) 2001-02-28 2003-04-01 Home Diagnostics, Inc. Method for determining concentration of an analyte in a test strip
US6562625B2 (en) 2001-02-28 2003-05-13 Home Diagnostics, Inc. Distinguishing test types through spectral analysis
KR100404576B1 (ko) * 2001-03-07 2003-11-12 엘지전자 주식회사 개선된 마스크 지지체를 갖는 칼라 음극선관
KR20030029826A (ko) * 2001-06-21 2003-04-16 코닌클리케 필립스 일렉트로닉스 엔.브이. 칼라 선택 전극을 구비한 칼라 디스플레이 튜브

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1470260A (fr) * 1962-06-29 1967-02-17 Rca Corp Tube à rayons cathodiques à masque d'ombre
DE1426908A1 (de) * 1962-06-29 1968-12-12 Simmering Graz Pauker Ag Kombiniertes Gegendruck-Kondensationsverfahren einer Dampf-Turbinenanlage zur geregelten Abgabe elektrischer Leistung und Bereitung von Heisswasser mit wattmetrischem Regelimpulsgeber in der elektrischen Kupplungsleitung zwischen Fremdnetz und Eigensammelschiene
US3639799A (en) * 1969-04-02 1972-02-01 Tubal Ind Inc Shadow mask with reinforcing ring for colored television picture tube
GB1313071A (en) * 1970-06-15 1973-04-11 Rca Corp Shadwo-mask cathode-ray tube and frame assembly and method of making same
US3772555A (en) * 1972-03-30 1973-11-13 Gte Sylvania Inc Color cathode ray tube of the shadow mask variety
US4056755A (en) * 1975-12-22 1977-11-01 Rca Corporation Color picture tube having mask-frame assembly with reduced thickness

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3919674A1 (de) * 1989-06-16 1990-12-20 Nokia Unterhaltungselektronik Masken-rahmen-kombination fuer eine farbbildroehre

Also Published As

Publication number Publication date
FR2420205A1 (fr) 1979-10-12
FR2420205B1 (de) 1980-11-14
DE2966214D1 (en) 1983-11-03
JPS54127276A (en) 1979-10-03
EP0004245A1 (de) 1979-09-19
US4308485A (en) 1981-12-29

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