U.S. patent number 3,755,027 [Application Number 05/197,277] was granted by the patent office on 1973-08-28 for method of manufacturing a gas discharge panel and panel manufactured by said method.
This patent grant is currently assigned to U.S. Philips Corporation. Invention is credited to Johannes Andries Arnoldus Gilsing.
United States Patent |
3,755,027 |
Gilsing |
August 28, 1973 |
METHOD OF MANUFACTURING A GAS DISCHARGE PANEL AND PANEL
MANUFACTURED BY SAID METHOD
Abstract
A gas discharge panel of which one or both panel plates are
provided with cavities in the bottoms of which a conductor extends,
which cavities and conductors are pressed in the softened material
of the panel plate by means of a pressure plate in which cores in
the form of balls or rods are secured, which cores comprise in the
free end a groove in which the conductors are provided, which
conductors remain behind in the panel plate after impression.
Inventors: |
Gilsing; Johannes Andries
Arnoldus (Eindhoven, NL) |
Assignee: |
U.S. Philips Corporation (New
York, NY)
|
Family
ID: |
19811601 |
Appl.
No.: |
05/197,277 |
Filed: |
November 10, 1971 |
Foreign Application Priority Data
|
|
|
|
|
Nov 19, 1970 [NL] |
|
|
7016929 |
|
Current U.S.
Class: |
156/67; 40/544;
156/219; 156/292; 156/298; 264/272.16; 313/493; 445/24; 156/182;
156/242; 156/293; 156/303.1; 264/322; 313/491; 313/584 |
Current CPC
Class: |
H01J
17/49 (20130101); Y10T 156/1039 (20150115); Y10T
156/109 (20150115) |
Current International
Class: |
H01J
17/49 (20060101); B44d 005/00 (); B29d
003/00 () |
Field of
Search: |
;156/67,102,104,210,219,298,303.1,230,242,292
;264/251,271,272,273,322,332 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Leavitt; Alfred L.
Assistant Examiner: Lewris; Basil J.
Claims
What is claimed is:
1. A method of manufacturing a gas discharge panel for the display
of pictures, the discharge panel including an upper panel plate and
a lower panel plate, each plate having a number of mutually
insulated parallel strip-shaped conductors, the conductors of the
lower panel plate intersecting the conductors of the upper panel
plate at an angle, and also including a gas atmosphere which is
provided between the panels, said method comprising the steps
of:
immovably securing a plurality of cores in parallel rows in a
pressure plate, said cores projecting beyond the surface of the
plate;
providing a groove in the free end of each core, said grooves being
oriented in the same direction in each row and being parallel to
grooves in other rows;
placing strip-shaped conductors in each row of grooves in said
cores;
softening the upper plate of the discharge panel, said upper plate
consisting of light-pervious insulating material;
forcing the pressure plate with said strip-shaped conductors into
said softened upper plate to deposit said strip-shaped conductors
into said upper plate and to create cavities in said upper plate by
said cores; and
separating said pressure plate from the upper panel plate, the
conductors and cavities remaining in the upper plate.
2. The method of claim 1 also including the steps of:
making parallel channels in a second lower plate of the discharge
panel, said lower plate consisting of an insulating material;
inserting strip-shaped conductors in said channels; and
lowering the surface of each of the strips to be below the surface
of said second lower plate.
3. The method of claim 2 also including the steps of:
placing the upper plate on the lower plate with said upper plate
strips at an angle to said lower plate strips, said lowered strips
of said lower plate forming channels which communicate with said
cavities of said upper plate; and
sealing the upper and lower panel plates together.
4. The method of claim 1 wherein the strip-shaped conductors are
provided with projections which extend from the upper plate after
separation, into the cavities formed by the cores.
5. A method as claimed in claim 1 wherein the cores consist of
balls, and the method includes the steps of insetting the balls in
the pressure plate to approximately half of their diameter and
securing them in said plate.
6. A method as claimed in claim 1 wherein the cores consist of
cylinders, and the method includes the steps of partly insetting
the cylinders in the pressure plate and securing them in said
plate.
7. A method as claimed in claim 1, including the step of providing
luminescent material on the walls of the cavities.
Description
The invention relates to a method of manufacturing a gas discharge
panel for displaying pictures consisting at least of a lower panel
plate and an upper panel plate, the upper panel plate consisting of
a light-pervious material, each plate comprising a number of
mutually insulated parallel strip-shaped conductors, the conductors
of the lower panel plate intersecting the conductors of the upper
panel plate at an angle. The invention furthermore relates to a gas
discharge panel manufactured by this method. The conductors are in
contact with a gas atmosphere which is contained in cavities which
are present in parallel rows at the area of the points of
intersection of the conductors.
The provision of a large number of cavities in a plate which
consists of an insulating material is not simple, particularly if
at the bottom of said cavities strip-shaped conductors have to be
present which must contact a gas atmosphere which is to be
introduced in the cavities afterwards.
It is known per se to provide a large number of cavities in a plate
by forcing balls which are partly enclosed in holes of a pressure
plate in said plate.
The balls were lying loosely in the holes of the pressure plate and
were kept at a given depth by means of pins.
It was not possible herewith, however, to provide conductors in the
bottom of the cavities. The known method was used to manufacture
projection screens having a large number of reflecting cavities of
very small dimensions.
According to the invention, in a method of manufacturing a gas
discharge panel for displaying pictures consisting at least of a
lower panel plate and an upper panel plate, the upper plate
consisting of a light-pervious material, each plate comprising a
number of mutually insulated parallel strip-shaped conductors, the
conductors of the lower panel plate intersecting the conductors of
the upper panel plate at an angle, all conductors being in contact
with a gas atmosphere which is contained in cavities provided in
parallel rows at the area of the points of intersection of the
conductors, the cavities and the conductors are provided in at
least one of the panel plates by means of a pressure plate in which
a number of cores corresponding to the number of cavities is
immovably secured, a groove which extends in the direction of the
rows being provided in the free end of each core, the strip-shaped
conductors being placed in said groove and being forced with the
cores in the softened panel plate by the pressure plate, the
pressure plate being then separated again from the panel plate, the
strip-shaped conductors in the panel plate remaining behind in the
bottoms of the cavities produced by the cores.
Since the strip-shaped conductors have a comparatively large length
and are therefore situated in the grooves of a large number of
cores which are present in a row, they are clamped sufficiently
rigidly to avoid falling out of the grooves if the pressure plate,
with the conductors directed downwards, is pressed on the soft
panel plate. The conductors are embedded in the material of the
panel plate on the bottoms of the cavities produced by the cores.
Said panel plate constitutes the upper panel plate and is then
placed on the lower panel plate in such manner that the
strip-shaped conductors embedded in the material of the lower panel
plate intersect the conductors of the upper panel plate at an
angle, usually at right angles, after which the panel plates are
connected together in a vacuum-tight manner. All the cavities
communicate with each other and with an exhaust tube, for example
by partly etching away the conductors embedded in the surface of
the lower plate so that shallow channels are formed which
communicate the cavities with each other. It is also possible,
however, that the separation walls between the cavities do not
extend entirely up to the surface of the panel plate, so that the
cavities, after the panel plates have been placed one of the other,
remain in local communication with each other. The cavities can be
evacuated through an exhaust tube after which the desirable gas
atmosphere can be introduced into the cavities through the exhaust
tube.
In order that the invention may be readily carried into effect, it
will now be described in greater detail, by way of example, with
reference to the accompanying drawings, in which
FIG. 1 is a cross-sectional view through a gas discharge panel
manufactured by means of the method according to the invention,
FIG. 2 is a perspective view of an upper panel plate and
FIG. 3 is a perspective view of a lower panel plate, while
FIG. 4 is a sectional perspective view of an embodiment of a
pressure plate, and
FIG. 5 is a plan view of the pressure plate shown in FIG. 4,
while
FIGS. 6 and 7 are sectional views of other embodiments of pressure
plates, and
FIG. 8 is a cross-sectional view through another embodiment of a
gas discharge panel, while
FIG. 9 is a perspective view of a pressure plate using cores of a
different shape.
In FIGS. 1, 2 and 3, reference numbers 1 and 2 denote a lower panel
plate and an upper panel plate, respectively. A number of mutually
insulated, strip-shaped conductors 3 which are arranged in parallel
are embedded in the lower panel plate 1.
Embedded in the upper panel plate 2 are mutually insulated,
parallel strip-shaped conductors 4 which in this case are provided
with cams or teeth 5 which extend in the discharge cavities 6. So
the conductors 4 are situated in the bottoms of the cavities 6 and
intersect the conductors 3 at an angle, in this case at right
angles.
The cavities 6 contain a suitable gas atmosphere. The upper side of
the conductors 3 is slightly etched away so that channels 7 are
formed which communicate the cavities 6 with each other. The
channels 7 may empty on one or both sides of the panel 1,2 into a
transverse channel, not shown, which communicates with an exhaust
tube which is not shown either.
At the outer edges the panel plates 1 and 2 are secured together in
a vacuum-tight manner by means of a suitable cement, for example a
synthetic resin, or a low melting glass. The panel plate 1 may
consist of glass or a ceramic material. The upper panel plate 2
must consist of a light-pervious insulating material which can be
softened, preferably glass.
A panel plate 2 can be manufactured by means of a pressure plate 8
as is shown in FIG. 4. The metal pressure plate 8 comprises a large
number of holes 10, made, for example, by means of photographic
etching. Cores in the form of steel balls 9 are immovably secured
in the holes 10, for example, by soldering or welding. The balls 9
are pressed in the holes 10 up to half of their diameter. The
thickness of the pressure plate 8 is preferably equal to the radius
of the balls 9 so that these can be pressed into the holes until
they bear on the base plate 11 on which the pressure plate 8 may be
secured. The base plate 11 may be a die. The balls 9 are
commercially available in accurate dimensions.
When the balls 9 are immovably secured in the pressure plate 8,
grooves 12 are sawn or milled in the rows of balls 9 which are
situated in the direction of the conductors 4 as is shown in FIG.
5.
In order to manufacture an upper panel plate 2, conductors 4 are
placed in the grooves 12 of the rows of cores. As a result of the
large number of cores in each row, the conductors 4 are held
sufficiently rigidly in the grooves 12 so that the pressure plate 8
with the die 11 can be pressed upside down on an insulating panel
plate 2 which is softened, for example, by heating. The conductors
4 in the panel plate 2 are embedded in the bottoms of the cavities
6 produced by the balls 9 serving as cores. The conductors 4 may be
provided with cams 5 which project in the cavities 6. The walls of
the cavities 6 are then covered with a luminescent material 13.
The lower panel plate 1 is provided with embedded strip-shaped
conductors by pressing the conductors 3 in the softened material of
the panel plate 1.
The upper surface of the conductors 3 is brought below the surface
of the panel plate 1 by etching so that channels 7 are formed.
The panel plates 1 and 2 are then placed on each other, connected
together in a vacuum-tight manner, the cavities 6 are evacuated and
filled with a suitable gas atmosphere. If a suitable potential
difference is applied between two conductors 3 and 4, a gas
discharge will occur in the cavity situated at the point of
intersection of said conductors, which gas discharge, also due to
the luminescent material 13 present on the wall of the cavity 6,
will be visible from the upper side of the plate 2 as a light
spot.
The connection of the balls 9 in the holes of the pressure plate 8
may also be effected by forcing the balls in holes smaller than the
ball diameter of the pressure plate 8 as is shown in FIGS. 6 and 7.
In this case also the balls are also welded or soldered since
otherwise they may work loose when the grooves 12 are provided.
In FIG. 7 the balls 9 engage each other. The advantage is that when
the balls 9 are forced in the panel plate 2, connections between
the cavities 6 are formed as a result of which the channels 7 may
be omitted. It is then possible to place two equal panel plates 2,
2' with the cavities on each other so that substantially sperical
cavities 6, 6' are formed as is shown in FIG. 8.
As is shown in FIG. 9, cylindrical cores 14 may also be used
instead of balls. Such cylindrical cores can be given accurately
the same dimensions by sawing them from a rod. The advantage of
such cylindrical cores 14 is that the height of the cavities
obtained therewith is arbitrary. The ready detachment of the cores
after forcing them in a soft panel plate can be obtained by making
the cylinders 14 from a material having a larger coefficient of
thermal expension than that of the material of the panel plate.
The sticking of the insulating material of the panel plate to the
cores can be avoided by covering the cores, prior to providing the
conductors 4 in the grooves 12, with a thin powdered layer of, for
example, oil, soot, graphite, aluminium oxide or another suitable
material.
Of course the cores may also have other suitable shapes. For
example, they may be conical or oval.
It is also possible to press the cores in a flat non-perforated
pressure plate and welding them if the material of the cores is
sufficiently hard in relation to the hardness of the material of
the pressure plate.
* * * * *