DE2347283A1 - INDICATOR TUBE FOR ILLUMINATED SIGNS AND METHOD OF MANUFACTURING IT - Google Patents

Description

PATENTAIiWA LT

8 MUNICH 71

HINDELAIiGSTHASSE 8 TELEPHONE OSll / 75 7725 TELEÖHAMMADHESSE: PATITIA MUNICH

Nippon Electric Kagoshima, Limited 12 699, Lakemoto, Jzumi-shi, Kagoshima

Japan

Illuminated sign display tube and process for their manufacture

The invention "relates to a display tube for at least a luminous sign with a plate-shaped substrate made of an insulating material, a cathode on the front side of the substrate, devices for controlling the electrons emitted by the cathode on the front side of the substrate and carrier on the substrate for the control devices along longitudinal edges of the substrate.

The invention also relates to a method for producing such display tubes.

Display tubes of this type are "known to contain electrons from a cathode through a grid onto those luminous segments on the front or visible side of a substrate be emitted from insulating material, which are selectively at a positive potential to the segments in a

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to make the selected image shine. The grid is used for a substantially uniform division of the electrons on the segments that are at positive potential. The grid is usually also used for acceleration of electrons. A display tube for substantially simultaneous viewing of a plurality of selected ones Numbers, symbols, and / or letters, referred to herein as characters, often contain multiple grids one grid per character. Also includes the display tube an electrically conductive film or layer on the inside of a vacuum tube, which is the cathode, houses the grids and the substrate of insulating material. The film or the layer is used for electrostatic shielding the inside of the vacuum tube. The invention is based on a display tube for displaying 8 digits described, although the invention is just as suitable for a display tube with only one single or a different number of digits or characters can be displayed.

In a display tube, the substrate is formed from an insulating material with luminous segments on the substrate, arranged in several groups according to the shapes of the characters are a base plate structure together with supports on the base plate for the cathode and grids and conductors extending outwardly from the substrate for the segments, cathode and grids. As below As will be explained in more detail, conventional display tube base assemblies have various forms Disadvantages such as poor manufacturing quality or high reject rates in their manufacture, interfering luminescence and / or false reports. In addition, the electrically conductive film on the inside of the vacuum tube can be damaged.

The object of the invention is therefore, to have a display tube specify a base plate structure described above,

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which is easy to manufacture and has a high quality. The electrically conductive film on the inside of the vacuum tube should not be damaged. Also should Interfering luminescence and / or false displays can be avoided.

The object is achieved according to the invention in a display tube of the type mentioned at the outset in such a way that the substrate Has projections along its longitudinal edges which extend sideways over the support for the control devices stretch out.

An advantageous embodiment according to the invention consists in that each carrier for the control devices has a central one Has projection as a link to a separated lattice support frame, the projections of the substrate The projections of the carrier for the control devices, such as one or more grids, are left when cutting the girders from at least two lattice girder frames.

Further advantageous embodiments and developments of the invention result from further features of the subclaims and the description below.

The method for producing the display tubes according to the invention is that the along a longitudinal edge of the Substrates to be attached carrier for the control devices (grid) before their assembly on the substrate via middle Projections are held one after the other at certain distances from one another on a frame part that the carrier with the Frame part attached to the substrate in their predetermined positions v / earth, the projections on the carriers respectively come to lie between adjacent lateral projections of the substrate and that after the attachment of the carrier on the substrate, the frame is separated from the lattice girders

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is, the gate projections of the substrate to the Laterally protrude beyond the girders that remain behind.

Exemplary embodiments according to the invention are shown schematically in the drawings.
Herein shows:

1 is a perspective view of a display tube partially broken away;

iig. Figure 2 is a perspective view of a base plate assembly as part of a conventional display tube,

a perspective view of a base plate structure according to a first embodiment according to the invention and

Mg. ' 4 is a corresponding view of a base plate structure according to a further embodiment of the invention.

Before the invention is described and explained in more detail on the basis of two preferred exemplary embodiments, For clarification and better understanding of the invention, a conventional display device and its disadvantages are described described with reference to FIGS. 1 and 2.

Fig. 1 shows a display tube for several luminous digits. The tube consists of a vacuum piston 11, one in which Piston 11 held by means not shown base plate structure 12, a cathode 13 extending in its longitudinal direction in the piston 11 in front of or above the base plate 12, several grids 14 between the cathode -13 and the base plate structure 12, with one grid per digit

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is present, several plug contacts 15 on the tube foot for the cathode 13 »the grids 14 and the anode segments of the Base plate 12. The grids are used to distribute the Electrons passing through the cathode 13 are substantially uniform are emitted on those anode segments which are selectively connected to positive via associated plug-in contacts 15 Potential. Located on the inside of the vacuum tube 11 An electrically conductive PiIm or layer (not shown) is mainly used for electrostatic shielding the inside of the vacuum tube 11 from the electrostatic PeId that the behavior of the electrons in the vacuum tube 11 can disturb.

Pig. Fig. 2 shows an example of a conventional base plate structure 12 consisting of an insulating material substrate 20 such as ceramic, glass, steatite or the like and several Luminous material segments 21, which are in groups on the front of the substrate 20 are arranged. The end faces of the phosphor segments 21 are preferably flush with the front side of the substrate 20. Such an arrangement of the phosphor segments 21 is also called "arranged on the front surface" designated. The phosphor segments 21 of a group are arranged in such a way that they essentially form an "eight". In addition, one phosphor segment group has an additional one Segment for a decimal point and a segment for the display of a "four", which can also be dispensed with. In a known manner, each of the phosphor segments forms 21 together with an electrically conductive film or layer (not shown) behind the phosphor segment with Pig. 1 designated anode segment. The base plate 12 also contains several segment conductors 22a, 22b, 22c, 22d, 22e, 22f, 22g, 22h and 22i, those with the electrically conductive layers behind the corresponding phosphor segments are connected, lattice girders 23 for the respective grids 14 »those on the front side of the substrate 20 in pairs on both sides of the individual phosphor segment groups

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and arranged along the longitudinal sides of the substrate, grid conductors 241, 242, 243, 244, 245, 246, 247 and 248, the are connected to at least one of the corresponding pairs of the lattice supports 23, two cathode supports 251 and 252 and two cathode conductors 261 and 262 which are connected to the corresponding cathode supports.

The beams 23 and 25 (251 and 252) and the conductors 22 (22a, 22b ... and 22i), 24 (241, 242 ... and 248) and 26 (261 and 262), are usually soldered to metallic conductors (not shown) leading to the front of the substrate 20 are arranged. The connections between the electrically conductive films and the corresponding segment conductors 22, between the grid supports 23 and the corresponding grid conductors 24 and between the cathode supports 25 and the corresponding cathode conductors 26 represent printed circuits, which preferably consist of plates that are arranged between layers of a multilayer ceramic substrate 20. The phosphor segments are then placed on the corresponding electrically conductive layers to form the anode segments. In many cases it was inevitable that the lights would layer off with the Beams 23 and 25 and lines 22, 24 and 26 came into contact. Phosphor layers on some or all of the lattice supports 23 and came to rest on the grid conductors 24 generated false or scattered luminescence during operation. The fluorescent Layers that come to lie on some or all of the conductors 22, 24 and 26 often bridge the conductors. Since a phosphor is a semiconductor, each of the phosphor layers constitutes a resistance of the order of one hundred ohms to a few kilo ohms, so that between the conductors 22, 24 and / or 26 short-circuits may be present, which results in undesirable displays and high loads occur on the power supply unit (not shown) for the display tube. The removal of such misplaced phosphor layers is very troublesome.

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In Pig. 2 can be the free ends of conductors 22, 24 and 26 be combined into four groups by frame conductor parts 271-, 272, 275 and 274. This makes it possible to to form the electrically conductive pilms electrically and at the same time to apply a voltage between the groups of conductors. The phosphor segments 21 are or can be in be formed electrically in the same way and at the same time. Because each of the leader groups through frame leader parts 271, 272 and 273 are connected, contain segment and grid conductors, it is inevitable that misplaced Phosphor layers, such as those on the lattice supports 23, Cause interfering luminescence. Although the frame conductor technology to increase the quality of the soldering of the conductors 22, 24 and 26 to the substrate 20 and the formation of the electrically conductive layers and the phosphor segments 21 on the Subs + rat 20 is useful, the application of the frame conductor technology is still inadequate with regard to the poor manufacturing quality the base plates 12 and thus also the display tubes and the resulting interference luminescence. Besides, the Frame conductor technology not suitable for the lattice supports 23 and the cathode supports 25. Soldering the beams 23 and 25 one after the other on the substrate 20 complicates the manufacture of the base plate structure and can reduce the quality of the Affect manufacturing. This is not only due to the fact that soldering the brackets 23 and 25 is particularly time-consuming, but that it is also difficult to arrange the carriers 23 and 25 in the correct position.

iig. 3 shows a base plate structure 12 according to a first embodiment of the invention, with details, those in Pig. 2 correspond with the same reference numerals are provided. Deviating from the conventional Pig base plate unit. 2 are the segment conductors 22 on the front side of the substrate 20 at its longitudinal ends in each case directed outwards. In contrast, the lattice

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Head 24 on the back of the substrate 20 at the longitudinal ends thereof directed outward. It is thus possible to combine the segment conductors 22 and the grid conductors in different groups by means of frame conductor parts 271 and on the one hand and frame conductor parts 2-73 and 274 on the other hand, in order to avoid the undesired display during display operation and the consumption of electrical energy through short circuits of segment conductors 22 and lattice conductors 24 in different conductor groups allows the voltage for the phosphor segments 21 to be applied only to the segment conductor groups which are combined by the frame conductor parts 271 and 272. This prevents the undesired arrangement of phosphor layers on the lattice supports 23 Significantly improved manufacturing quality of base plates while avoiding interfering luminescence The grid conductors 24 in S ¹ Ig are sent out do not acquire sufficient energy when reaching the cathode supports 251 and 252, which is essentially at the same potential as the cathode 13, the defective phosphor layers, if they are formed on these supports 252 and 252, show no luminescence. It is therefore possible to group the cathode conductors 261 and 262 in one of the conductor groups for the segment conductors 22 and the grid conductors 24.

With regard to i "ig. 3 it should be emphasized that the lattice girders 23 are arranged on the rear side of the substrate 20 and that the lattice girders 23 from the front side of the substrate 20 are accessible through cutouts that are available for each lattice girder 23 and each lie between projections 28, which extend on the longitudinal sides of the substrate body 20 above the lattice girders 23. It turns out that the free

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Ends of the projections 28 the entire width of the base plate structure.es 12 and are therefore suitable for the electrically conductive layer on the inside of the vacuum tube 11 to protect against damage in an advantageous manner · The lattice girders 23 are on the back of the projections 28 held. Overflows or unnecessary, fluorescent layers, if they are formed on the lattice beams 23, they do not result in any spurious luminescence when the display tube is viewed from the front.

In Fig. 4, corresponding parts are from Pig. 3 are provided with the same reference numerals. Due to the projections 28 on the Substrate there is the possibility of the lattice girders 23, which are to be arranged along each longitudinal edge of the substrate 20, prior to their assembly by a frame ladder part (not shown) similar to the frame ladder parts 271 to 274 to form a lattice girder frame connect to. This improves the manufacturing quality of the base plate structure and thus also the phosphor display tube remarkably increased. The lattice girders can be attached to the body of the substrate 20 within the floor line of the recesses are fastened between adjacent projections 28, better than only on the projections 28. It it is therefore possible to dispense with some projections 28 which are shown in FIG. With the projections 28, which extend beyond the central protrusions 29 on the lattice girders which remain after being on the substrate 20 on the respective sides of the phosphor segments 21 attached lattice girders 23 of the lattice support frame are cut off, it is possible to oppose the electrically conductive film on the inside of the vacuum tube 11 Protect from damage.

With the lattice girders 23 attached to the front of the Substrate 20, as is the case in the second embodiment

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If, it is also possible, the grid conductor 24 in the longitudinal direction on the front side on the end faces and the segment conductors 22 in the longitudinal direction on the rear side on the end faces of the Substrate 20 to be arranged. When the lattice girders 23 are attached to the back of the substrate 20, as in the first Execution example so it is possible to eliminate the superfluous ones Leucbtstoffschiehten on the lattice girders 23 by brushing or to remove bubbles with air in the case of segments 21 specially protected by masks, without any damage the! fluorescent segments 21 occurs

Claims

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Claims (1)

Claims ί 1.J indicator tube for at least one illuminated sign with a plate-shaped substrate made of an insulating material, a cathode on the front side of the substrate, devices to control the electrons emitted by the cathode on the front side of the substrate and carrier on the Substrate for the control devices along longitudinal edges of the substrate, characterized in that the substrate (12) has projections (28) along its longitudinal edges which extend sideways over the. Carrier (23) for the control devices stretch out. 2. Display tube according to claim 1, characterized in that each carrier (23) for the control devices has a central one Has protrusion (29) as a link to a separated girder frame, the protrusions (28) of the substrate (20) protrude beyond the projections (29) of the carrier. 3. Display device according to claim 1, wherein at least one phosphor segment is arranged on the front side of the substrate, characterized in that the conductor (22) for the phosphor segments (21) on the front side of the substrate (20) at the end faces ¹ in the longitudinal direction outward extend and that conductors (24) for the control devices on the rear side of the substrate at the end faces extend in the longitudinal direction outward. 4. Display tube according to claim 1, characterized in that the carriers (23) for the control devices are attached to the rear side of the substrate. _.-- '" 409813/0950 ~ ¹² - 5. A method for producing the display device according to any one of claims 1 to 4 »characterized in that the Support for the control devices (grid) to be attached along a longitudinal edge of the substrate before their assembly on the substrate via central projections one after the other at certain distances from one another Frame part are held that the carrier with the frame part on the substrate in their predetermined positions are attached, the projections on the supports between adjacent lateral projections of the Substrates come to rest and that after the attachment of the carrier on the substrate, the frame of the lattice girders is separated, the projections of the substrate projecting laterally beyond the projections remaining on the carriers. 4098 13/0950 Le rs e