[0001] The present invention relates to a cathode ray tube or CRT socket comprising a housing,
a focus connection contact and a focus spark-gap contact, these contacts along with
other necessary contacts being built in the housing.
[0002] Figs. 11 and 12 show a conventional CRT socket. As seen from these drawings, a focus
connection contact 2 and focus spark-gap contacts 3 and 4 along with other necessary
contacts are built in a socket housing 1. The focus connection contact 2 has a resilient
terminal piece 2a at its end. As shown, the resilient terminal piece 2a is formed
by folding the end of the strip conductor. The focus spark-gap contact 3 or 4 has
a spark electrode 3a and a terminal piece 3b. These terminal pieces are arranged to
confront each other. As shown in Fig. 13, the core end 5a of a high-voltage lead conductor
5 is inserted between these terminal pieces 2a and 3b, together constituting a snap-in
terminal. The spark electrode 4a of the focus spark-gap contact 4 is positioned a
predetermined distance apart from the spark electrode 3a of the focus spark-gap contact
3 in confronting relation.
[0003] The terminal piece 2a has a very strong resilient force to push the core end of the
high-voltage lead conductor 5 against the terminal piece 3b lest the core end 5a of
the high-voltage lead conductor 5 should slop off from the snap-in terminal. Therefore,
once the core end 5a of the high-voltage lead conductor 5 has been inserted in the
snap-in terminal, it cannot be pulled out and removed.
[0004] The hook-like shape of the terminal piece 2a makes it still more difficult to remove
the core end 5a. Maintenance and checking work, however, necessitate removal of the
high-voltage lead conductor. In this connection the conventional structure is inconvenient
in maintenance and checking work. Also, disadvantageously the conventional structure
does not permit a person to check by sight whether the core end of the high-voltage
lead con ductor has been fully pushed into the snap-in terminal.
[0005] With the above in mind one object of the present invention is to provide a CRT socket
structure which permits easy removal and subsequent insert of the core end of a high-voltage
lead conductor into an associated snap-in terminal, and permits checking by sight
of connection to the high-voltage lead conductor.
[0006] To attain this object a CRT socket comprising a socket housing, a focus connection
contact and a focus spark-gap contact, these contacts along with other necessary contacts
being built in said socket housing, said focus connection contact being connected
to said focus spark-gap contact and to a high-voaltage lead conductor, is improved
according to the present invention in that: said focus spark-gap contact has a snap-in
terminal to connect to said high-voltage lead conductor, said snap-in terminal being
composed of a stationary contact piece and a movable contact piece, confronting each
other, said socket housing having a spark electrode compartment opening upwards and
containing the spark electrode of said focus spark-gap contact, and said socket housing
having a socket cover detachably fixed to said spark electrode compartment to close
it, said socket cover having a hollow casing to contain the snap-in terminal of said
focus spark-gap contact with its stationary contact piece fixedly held in position
in said hollow casing, and said socket cover having a press-fit cover to close said
hollow casing, said press-fit cover having a projection to enter said hollow casing
and push said movable contact piece against said stationary contact piece when closing
said hollow casing.
[0007] In removing the core end of a high-voltage lead conductor from the confronting stationary
and movable contact pieces of the snap-in terminal of the focus spark-gap contact,
the press-fit cover is opened to put the movable contact piece apart from the stationary
contact piece of the snap-in terminal, thereby putting the core end of the high-voltage
lead conductor in stress-free condition. In connecting the core end of the high-voltage
lead conductor to the snap-in terminal, the core end of the high-voltage lead conductor
is placed between the stationary and movable contact pieces of the snap-in terminal,
which pieces separate a distance enough to allow the inserting of the core end. The
insertion of the core end can be checked by sight. Then, the press-fit cover is closed
so that its projection may push the movable contact piece, thus assuring reliable
connection of the high-voltage lead conductor to the snap-in terminal of the focus
spark-gap contact.
[0008] Other objects and advantages of the present invention will be understood from the
following description of a CRT socket according to one embodiment of the present
invention, which is shown in accompanying drawings:
Fig. 1 is a side view of the CRT socket partly broken to show the inside;
Fig. 2 is a plane view of the CRT socket;
Fig. 3 is an end view of the CRT socket as seen from the left of Fig. 2;
Fig. 4 is a side view of the focus connection contact used in the CRT socket;
Fig. 5 is a side view of the focus connection contact as seen from the left of the
contact of Fig. 4;
Fig. 6 is a plane view of the focus connection contact as seen from the top of the
contact of Fig. 4;
Fig. 7 is a front view of the focus spark-gap contact used in the CRT socket;
Fig. 8 is a side view of the snap-in terminal of the focus spark-gap contact as seen
from the left of the contact of Fig. 7;
Fig. 9 is a plane view of the snap-in terminal of the focus spark-gap contact as seen
from the top of the contact of Fig. 7;
Fig. 10 is a longitudinal section taken along the line X-X of Fig. 7;
Fig. 11 is a plane view of a conventional CRT socket;
Fig. 12 is a longitudinal section of the conventional CRT socket; and
Fig. 13 is a section of a part of the conventional CRT socket, showing how a high-voltage
lead conductor is connected to the focus spark-gap contact.
[0009] Figs. 1 to 10 show a CRT socket according to one embodiment of the present invention.
A focus connection contact 12 has press contact terminal pieces 12a and 12b. These
pieces are formed by bending the end of a strip conductor in the form of inverted
"U" shape and making a slot 12c in the folded end ( See Figs. 4, 5 and 6 ).
[0010] A focus spark-gap contact 13 has a spark electrode 13a, a lateral extension contact
13b to connect the press contact terminal of the focus connection contact and a snap-in
terminal 13c to connect a high-voltage lead conductor 5 (See Figs. 7, 8 and 9). The
snap-in terminal 13c comprises a stationary contact piece 13c₁ and a movable contact
piece 13c₂. The movable contact piece 13c₂ is formed by folding a lateral extension
of the conductor strip, and the folded contact piece 13c₂ confronts the stationary
contact piece 13c₁. A high-voltage lead conductor 5 can be connected to the focus
spark-gap contact 13 by inserting its core end between the confronting stationary
and movable contact pieces 13c₁ and 13c₂. The movable contact piece 13c₂ had an outward
inclination 13c₃ and an inner-bent top 13c₄.
[0011] As shown in Fig. 1, a socket housing 11 has a spark electrode compartment 11a opening
upwards. It contains the spark electrode 13a of the focus spark-gap contact 13. A
socket cover 10 is detachably fixed to the spark electrode compartment. The socket
cover body 15 has a hollow casing 16 to contain the snap-in terminal of the focus
spark-gap contact with its stationary contact piece 13c₁ fixedly held in position.
[0012] Also, the socket cover 10 has a press-fit cover 17 hinged to the cover body 15 as
indicated at 18 to close the hollow casing 16. As best shown in Fig. 2, the press-fit
cover 17 has a notch 17a. A high-voltage lead conductor 5 can be put in the notch
17a, thereby permitting the press-fit cover 17 to be completely closed and locked
to the socket cover body 15 with locking means 19 and 20. The press-fit cover 17 has
a projection 21 to enter the hollow casing 16 and push the movable contact piece 13c₂
against the stationary contact piece 13c₁ when closing the hollow casing 16. The projection
21 has an inclined surface 21a, thereby assuring the smooth insertion of the projection
21 in the hollow casing 16.
[0013] The hollow casing 16 has a rectangular form in cross section. The stationary contact
piece 13c₁ is pushed against one wall 16a of the rectangular frame, and is fixedly
held. The hollow casing has a receptacle 16b for accepting a high-voltage lead conductor
on its side. The receptacle 16b has a tapering hole 16b₁ and a guide piece 16d for
guiding the insertion of the core end of the high-voltage lead conductor.
[0014] As may be understood from the above, a CRT socket according to the present invention
when used, permits checking by sight of the insertion of the core end of an associated
high-voltage lead conductor 5 between the stationary and movable contact pieces 13c₁
and 13c₂ of the focus spark-gap contact. The core end of the high-voltage lead conductor
5 can be pinched and firmly held between the stationary and movable contact pieces
13c₁ and 13c₂ against the stationary contact pieces 13c₁.
If removal of the high-voltage lead conductor from the CRT socket is desired for maintenance
or checking, the press-fit cover 17 is opened to remove its projection 21 from the
hollow casing 16, thereby putting the stationary and movable contact pieces 13c₁ and
13c₂ in stress-free condition in which the core end of the high-voltage lead conductor
5 can be easily removed. Also, in this stress-free condition the core end of the high-voltage
lead conductor 5 can be easily inserted between the stationary and movable contact
pieces 13c₁ and 13c₂.
A CRT socket comprising a socket housing, a focus connection contact and a focus spark-gap
contact, these contacts along with other necessary contacts being built in said socket
housing, said focus connection contact being connected to said focus spark-gap contact
and to a high-voltage lead conductor, characterized in that:
said focus spark-gap contact has a snap-in terminal to connect to said high-voltage
lead conductor, said snap-in terminal being composed of a stationary contact piece
and a movable contact piece, confronting each other, said socket housing having a
spark electrode compartment opening upwards and containing the spark electrode of
said focus spark-gap contact, and said rocket housing having a socket cover detachably
fixed to said spark electrode compartment to close it, said socket cover having a
hollow casing to contain the snap-in terminal of said focus spark-gap contact with
its stationary contact piece fixedly held in position in said hollow casing, and said
socket cover having a press-fit cover to close said hollow casing, said press-fit
cover having a projection to enter said hollow casing and push said movable contact
piece against said stationary contact piece when closing said hollow casing.