US3548235A - Face-plate for rectangular color television picture tube with land portions with recesses for receiving shadow mask support members - Google Patents

Description

Dec. 15, 1970 r J DRIEDIJK ETI'AL 3,548,235

FACE-PLATE FOR RECTANGULAR COLOR TELEVISION PICTURE TUBE WITH LAND PORTIONS WITH REcEssEs FOR RECEIVING SHADOW MASK SUPPORT MEMBERS Filed July 22, 1969 4 Sheets-Sheet 1 l O a Q 13 mu mmuummm'-.

INVENTORY JOHANNES DRIEDIJK BY JOHANNES A. VAN LEEUWEN JOHANNES H. STOVER Dec. 15, 1970 J. DRIEDIJK EI'AL 3,548,235

FACE-PLATE FOR RECTANGULAR COLOR TELEVISION PICTURE TUBE WITH LAND PORTIONS WITH RECESSES FOR RECEIVING SHADOW MASK SUPPORT MEMBERS Filed July 22, 1969 4 Sheets-Sheet 3 INVENTORS JOHANNES DRIEDIJK JOHANNES A. VAN LEEUWEN JOHANNES H. STOVER AGENT Dec. 15, 1970 J. DRIEDIJK ET AL FACE-PLATE FOR RECTANGULAR COLOR TELEVISION PICTURE TUBE WITH LAND PORTIONS WITH RECESSES FOR RECEIVING SHADOW MASK SUPPORT MEMBERS Filed July 22., 1969 4 Sheets-Sheet 2 Fig.7v

, INVENTORS JOHANNES DRIEDIJK JOHANNES A. VAN LEEUWEN JOHANNES H. STOVER AGENT Dec. 15, 1970 J. DRlEDlJK EI'AL 3,548,235

FACE-PLATE FOR RECTANGUL COLOR TELEVISION PICTURE TUBE WITH LAND PORTIONS WIT ECESSES FOR RECEIVING SHADOW MASK SUPPORT MEMBERS Filed July 22, 1969 4 Sheets-Sheet &

INVF'NTORS JOHANNES DRIEDIJK JOHANNES A. VAN LEEUWEN JOHANNES H. STOVER AGEN United States Patent US. Cl. 313-85 26 Claims ABSTRACT OF THE DISCLOSURE A rectangular shadow mask for a color television picture tube is supported by suspension members the free end of each of which is secured to the central portion of an Q-shaped resilient strip the width of which is parallel to the axis of the tube. This resilient strip presses, on either side of the connection of the suspension member, against the upright walls of a recess in a land portion provided in the glass of the upright edge of the window between two land portions on at least three points of contact situated near the upper and lower edges of the bent strip. A part of the strip engaging a surface serves as a fitting edge.

The invention relates to a color television picture tube having a rectangular color selection electrode which is secured in the tube immediately in front of the rectangular luminescent screen by means of strip-shaped resilient suspension members which are secured with their one end to the edge of the mask and the other end of which is supported by the upright edge of the cup-shaped window of the envelope. The strip-shaped suspension members preferably extend at right angles to the direction of the electron beams which are directed at the corners of the mask. The invention furthermore relates to a cup-shaped glass-window for such a tube.

According to the invention the free end of each suspension member is secured to the central portion of an S2- shaped resilient strip the width of which is parallel to the axis of the tube and which, on either side of the connection place of the suspension member, presses with said strip against the upright walls of a cupboard-like recess provided in the glass of the upright edge of the window between two thickenings on at least three points of contact situated near the upper and lower edge of the bent strip, a part of the strip engaging a surface which serves as a fitting edge. The recess preferably extends over a corner if it serves for a suspension member which is provided in a corner of the mask. The ends of the Q-shaped strip which are bent backwards serve for a flexible bending of the strip, so that it can be placed in the recess or taken out of it. These ends which are bent backwards may have a smaller width than the bent central portion of the strip which is situated between said ends.

Since the bent strip engages the upright walls of the recess at a few points situated near the upper edge and near the lower edge, a tilt-free clamping connection is obtained between the bent strip and the edge of the window. In order to prevent small deviations in the shape of the recess and of the bent strip in preventing the formation of the desired contact points near the upper and lower side of the strip, short saw cuts can be provided in the bent ends of the strip which extend in the longitudinal direction of the strip so that the lower edge of the strips can spring somewhat independentlyof the upper edge "ice and can always engage the glass walls. The upper and lower edge are to be understood to mean the edges which are situated farthest from and nearest to, respectively, the luminescent picture screen, the window being situated upwards with its open side.

The fitting edge may be constituted by a bottom extending throughout the width of the cupboard-like recess or by bottom parts exclusively near the side walls. The upper side of the thickenings may also serve as a fitting edge.

The side walls of the cupboard-like recess enclose an angle of from 2 to 7 with a plane at right angles to the upright edge of the window and parallel to the axis of the tube so as to have on the one hand a sufficient possibility of removing the die and to avoid on the other hand that the resilient ends of the Q-shaped strip should work loose. It is of advantage that the side walls of the cupboard-like recess and the upper sides thereof merge into each other with a radius of curvature of a few millimeters.

A particularly favourable embodiment is that in which the suspension strip is secured to the Q-shaped strip by means of a widened part which extends in the direction of the picture screen and which bears with its end against the rear wall of the cupboard-like recess.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which FIG. 1 is a perspective view of a corner of a window, and

FIG. 2 is a perspective view of a suspension member secured to the mask, while FIG. 3 is a diagrammatic plan view of a mask mounted in a corner of a window,

FIGS. 4 and 5 show two embodiments of the connection of a suspension strip with an omega-shaped bent strip,

FIG. 6 is a cross-sectional view at right angles to the picture screen of FIG. 3, and

FIG. 7 shows another embodiment of a suspension member.

FIGS. 8 and 9 show two other embodiments of a corner of the window;

FIG. 10 shows another embodiment of the connection of a suspension strip with an omega-shaped bent strip;

FIG. 11 is a cross-sectional view through the bisector plane of a corner of the window;

FIG. 12 shows a corner of a mask with supporting frame destined for combination with a connection of suspension strip and omega-shaped bent strip according to FIG. 2, 4, 5, 7 or 10.

Referring now to FIG. 1, reference numeral 1 denotes the picture surface of a window of the envelope of a color television picture tube. The window 1 has an upright edge 2 which has a thickened portion 4, in which a cupboard-like recess 3 is formed which extends over the corner point. The color selection electrode, in this case a shadow mask 15 shown in FIG. 2, comprises an upright edge 16 which changes into a flange 17. On the inside of said upright edge 16 a supporting strip 8 is welded which moreover provides a reinforcement of the mask 15. The strip 8 comprises a bent edge 10 to which the part 9 of the strip-shaped suspension member 7 is welded. The suspension member 7 extends approximately at right angles to the direction of electron beams passing through the corner point and hence makes an angle which is equal to approximately half the deflection angle, in this case approximately 45, with the plane of the mask 15. As a result of this a movement component of said mask in the direction of the picture surface 1 is obtained, if the mask 15 expands as a result of heating. Since the strip-shaped suspension member 7 extends approximately at right angles to the path of the electrons, this movement component can be sufiiciently large also without the use of bimetallic components. The member 7 may be formed integral with an omega-shaped strip 11 which with its bent portions situated on either side of the member 7 presses against the upright walls at the points 13 and presses against the inner wall 2" of the edges 2 of the cupboard-shaped recess 3 at the points 13' and 13". In order to ensure an accurately determined position of the strip 11 each time when it is placed in the recess 3, it is necessary that each of these parts of the strip 11 presses against the glass surfaces 5 and 2' (see FIG. 3) in at least three points denoted by 13, 13', and 13". The strip 11 ends in two free lugs 12 having a smaller width which serve for the flexible bending of the bent central portion of the strip 11. When the lugs 12 are pinched towards each other, the central portion of the strip 11 will experience a stronger bend and the points 13, 13, and 13" are released from the glass surface 5 and 2 so that the strip 11 can easily be removed upwards out of the recess 3 and the mask electrode can be removed from the window 1.

When the mask electrode is placed in the window 1, 2 the lower side of the strip 11 engages the bottom of the recess 3. In this case said bottom serves as a fitting surface. In order to ensure an accurate immovable engagernent of the lower edge of the strip 11 on the bottom, said edge is partly removed so that one or more, in this case two, projections 14 are formed (see FIGS. 4 and 5) which are to engage the bottom of the recess 3 used as a fitting surface 6.

Instead of the bottom 6, the upper side of the thickened portion 4 may be used as a fitting surface, in which case the strip 11 must be provided with suitable. projections.

In order to make the engagement against the glass of the points 13, 13', 13" situated near the upper and lower edge of the strip 11 slightly independent of each other, saw cuts or kerfs 19 can be provided as is shown in FIG. 4.

If it is desirable to manufacture the strip 11 and the suspension member from different materials, for example, to increase the rigidity and/or the displacement of the mask electrode 15 towards the picture surface 1 upon heating, or to increase the friction between the strip and the glass, for example, by manufacturing the strip from a material which oxidizes during welding the window to the cone, a separate suspension member 18 may be secured to the strip 11, for example, by welding or riveting as shown in FIG. 5.

The member 18 may be secured to a strip 10 with its end 20 as is also shown for the embodiment shown in FIGS. 2 and 3. If required, the suspension member 18 may consist entirely or partly of a bimetal, so that the angle which the part 10' encloses with the suspension member 18 is varied as a result of which the movement of the mask '15 towards the screen surface 1 can be increased. Therefore, the metal layer with the smallest coefiicient of expansion should lie at the inner side of the bend of member 18 so that at higher temperatures the angle of this bend becomes narrower and the part 20 moves in the direction of the screen.

As shown in FIG. 6, the upper contact points 13 of the bent strip 11 of FIGS. 2, 3, 4, and 5 with the wall 2' are chosen to be so that said points are situated entirely on theupper edge of the strip 11 while the contact points 13 of the strip 11 with the sides 5 of the recess 3 are situated lower. A torque is then set up which wants to urge the upper edge of the strip 11 in the direction of the centre of the mask, as a result of which the lower edge of the strip 11 is forced against the wall 2 at 13". The strip 11 hence engages the walls of the recess 3 in at least three points 13, 13', and 13" with each of the. parts situated on either side beside the connection place of the strip 11 with the suspension member 7, 18, or 21. The

lower edge of the strip 11 need not have any contact points with the sides 5. As a result of this the strip 11 may be slightly tapered towards the lower side which facilitates the removal of the mask 15 out of the window 1, 2 after pinching the lugs 12.

The suspension member need not be a strip having a constant width, but the width may increase in the direction of the bent strip 11 or may be in the form of a V, as is shown in FIG. 7 by 21. As a result of this the bent strip 11 becomes less flexible so that the connection of the mask 15 in the window 1, 2 is even better shockresistant.

In FIG. 8 the bottom of the recess in the wall of the upright edge does not extend throughout the width thereof but has been reduced to two cam-shaped parts 26 which serve as fitting surfaces for the projections 14 of the omega-shaped strip 11. The upperside 27 of the thickening 4 may also serve as a fitting surface, as will be described with reference to FIGS. 10 and 11. The upright walls of the recess have a straight portion of 4 mm. which merges into the upper surface 27 with a radius of curvature of 3 mm. The total recess up to the fitting surfaces 26 hence is 7 mm. in depth measured in the axial direction. The lower part of the rear wall of the recess is denoted by 28.

The difference between FIGS. 8 and 9 is that the camshaped fitting surfaces 26 are omitted and hence the side faces 5 of the recess continue further in the axial direction. In this case it is necessary to use the upper surfaces 27 of the thickenings 4 as fitting surfaces of the strip in the axial direction.

In FIG. 10, parts 33 from the bent ends of the strip 11 are bent outwards, which parts 33 rest on the upper surfaces 27 of the thickenings in FIGS. 8 and 9, which are formed as fitting surfaces. After the uppermost bend, the suspension strip 7 changes into a Wide part 29 which is secured to the strip 11 by means of a number of spot welds 30. The lowermost corners are slightly bent so as to prevent scratching of the wall; if desirable, the part 29 is slightly bent inwardly near the line 30 for purposes of adaptation to the shape of the glass. The corners 31 engage the wall 28.

FIG. 11 is a cross-sectional view of a corner of the window shown in FIGS. 8 and 9, respectively, comprising a supporting member as shown in FIG. 10, arranged along the bisector plane. It will be obvious that the possibility of tilting is considerably restricted as a result of the part 29.

In FIG. 12 the mask has a heavy supporting frame 34 which can be secured to an assembly shown in FIG. 4, 5, 7 or 10 by means of a welded strip 8, 10.

What is claimed is:

1. A color television picture tube having a rectangular color selection electrode, particularly a shadow mask, which is secured in the tube immediately in front of the rectangular luminescent screen by means of strip-shaped resilient suspension members which are secured with their one end to the edge of the color selection electrode, and the other end of which is supported by the upright edge of the window, characterized in that said other end of each supporting member is secured to the central portion of an omega-shaped resilient strip the width of which is parallel to the axis of the tube and which presses with said strip on either side of the connection place of the suspension member on at least three contact points situated near the upper and lower edge of the strip against the upright walls of a cupboard-like recess provided in the glass of the upright edge of the window between two thickenings, a part of the strip bearing on a surface serving as a fitting edge in the axial direction.

2. A color television picture tube as claimed in claim 1, characterized in that the fitting edge in the axial direction is formed by the bottom of the cupboard-like recess which extends throughout the width thereof.

3. A color television picture tube as claimed in claim 1, characterized in that the fitting edge in the axial direction is formed by the upper surfaces of the thickenings between which the cupboard-like recess is formed.

4. A color television picture tube comprising 2. rectangular color selection electrode, particularly a shadow mask, which is secured in the tube immediately in front of the rectangular luminescent screen by means of stripshaped resilient suspension members which, with their one end, are secured to the edge of the color selection electrode and the other end of which is supported by the upright edge of the window, characterized in that said other end of each supporting member is secured to the central part of an omega-shaped resilient strip the width of which is parallel to the axis of the tube and which presses with said strip on either side of the connection place of the suspension member on at least three contact points situated near the upper and lower edge of the strip against the upright walls of a cupboard-like recess provided in the glass of the upright edge of the window, a part of the strip bearing on a fitting edge.

5. A color television picture tube as claimed in claim 4, characterized in that a supporting member is provided near each corner of the color selection electrode, which supporting member is clamped in a cupboard-like recess formed in a thickened part of the upright window edge by means of an omega-shaped strip, which recess extends over a corner.

6. A color television picture tube as claimed in claim 5, characterized in that the ends of the omega-shaped strip bent backwards have a smaller width than the bent central portion of the strip.

7. A color television picture tube as claimed in claim 6, characterized in that the parts of the central portion of the strip adjoining the ends of the omega-shaped strip which are bent backwards, have kerfs therein extending in the longitudinal direction of the strip.

8. A color television picture tube as claimed in claim 7, characterized in that the lower edge of the bent strip is partly removed so that one or more projections are formed which bear on a surface of the recess serving as a fitting edge.

9. A color television picture tube as claimed in claim 8, characterized in that the mask comprises an upright edge with a flange Without supporting frame and that the suspension member extends over the flange and is secured to a transverse strip which is secured on either side of a corner of the mask to the upright mask edge and bridges said corner.

10. A color television picture tube as claimed in claim 1, characterized in that the suspension member is integral with the omega-shaped strip.

11. A color television picture tube, as claimed in claim 9, characterized in that the suspension member consists of a material different from that of the omega-shaped str1p.

12. A color television picture tube as claimed in claim 10, characterized in that the suspension member has a larger width towards the bent strip.

13. A color television picture tube as claimed in claim 12, characterized in that the suspension member is in the form of a V.

14. A color television picture tube as claimed in claim 4, characterized in that the bent strip is tapered towards the lower side.

15. A color television picture tube as claimed in claim 4, characterized in that the upper contact points of the bent strip with the inner wall of the recess are more remote from the picture surface than the contact points of the bent strip with the narrow side walls of the recess.

16. A color television picture tube as claimed in claim 15, characterized in that the mask is secured to a supporting frame consisting of a material having a larger thickness than the mask.

17. A cup-shaped rectangular glass window for a color television picture tube as claimed in claim 16, charac terized in that the upright edge comprises, on the inner side of the window in the corners, a thickened portion in which a cupboard-like recess is formed.

18. A cup-shaped window as claimed in claim 17, characterized in that the wall thickness of the upright edge on the inner side of the window increases gradually towards the corners.

19. A cup-shaped window as claimed in claim 17, characterized in that the upright walls and the bottom surface of the cupboard-like recess are formed as fitting surfaces in the axial direction.

20. A cup-shaped window as claimed in claim 17, characterized in that the upper sides of the thickenings are formed as fitting surfaces in the axial direction.

21. A cup-shaped window as claimed in claim 17, characterized in that the upper sides of the thickenings change with the side walls of the cupboard-like recess with a radius of curvature of a few millimeters.

22. A cup-shaped window as claimed in claim 17, characterized in that the side walls of the cupboard-like recess enclose an angle of from 2 to 7 with a surface at right angles to the upright edge of the window and parallel to the axis of the tube.

23. A supporting member for the color selection electrode of a television picture tube consisting of a resilient strip-shaped suspension member which is secured to the central portion of an omega-shaped strip having its ends bent backwards in which kerfs are provided which extend in the longitudinal direction of the strip.

24. A supporting member as claimed in claim 23, characterized in that cams are formed on the long side of the strip opposite to that to which the supporting member is secured.

25. A supporting member as claimed in claim 23, characterized in that parts serving as cams are bent outwards in the bent rims of the omega-shaped strip.

26. A supporting member as claimed in claim 23, characterized in that the strip-shaped suspension member is secured to the omega-shaped strip by means of a widened part which, in the direction at right angles to an axis of the strip, extends beyond the width thereof.

References Cited UNITED STATES PATENTS 3,387,159 6/1968 Schwartz et al. 313 3,358,170 12/1967 Fiore 31385X 3,450,920 6/ 1969 Engels et al. 313-85 JAMES W. LAWRENCE, Primary Examiner V. LAFRANCHI, Assistant Examiner US. Cl. X.R. 313-284, 292

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