Resistance element connecting structure of CRT socket

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the structure of a CRT (Cathode-Ray-Tube) socket for connecting a cathode ray tube used in a color television, etc., and particularly relates to a resistance element connecting structure ofthe CRT socket in which a resistance element is connected in series with a focus contact.

2. Description of the Background Art

In a CRT socket for connection to a cathode ray tube, an undesired radiating signal is generated by a high frequency signal applied to a cathode ofthe cathode ray tube through a focus circuit block. The high frequency signal influences the focus of an electronic beam. A terminal connected to a flyback transformer is attached to the CRT socket. Conventionally, a resistance element is connected in series between this terminal and a focus contact in the interior of the CRT socket to reduce the above influence.

The resistance element can be connected by directly soldering lead portions on both sides of the resistance element to the terminal and the focus contact. However, it is very difficult to make a soldering connecting work within a housing of the CRT socket, wherein the CRT socket is made as compact as possible.

Referring now to

FIGS. 11-13

, conventionally, a resistance element connecting structure

100

of the CRT socket connects both side lead portions of the resistance element in press contact with press contact slits concavely arranged in the terminal and the focus contact. A CRT socket

101

is assembled by attaching parts, to be described later, to a housing main body

102

from the rear. The housing main body

102

is formed by integrally molding a cylindrical housing

102

a

on one side (a lower side in

FIG. 11

) and a generally box-shaped housing

102

b

on the other side. A bottom face side of the box-shaped housing

102

b

has an open face to enable attachment of the constructional parts. After all ofthe parts are installed, the open face of the box-shaped housing

102

b

is covered with a bottom cover

102

c.

The cathode ray tube is connected to a planar side of the cylindrical housing

102

a

. The cathode ray tube is attached from a bottom face side of the cylindrical housing

102

a

in contact with pins of a neck portion of the cathode ray tube such that plural contacts

104

are located on the same circular circumference on this plane side.

A contact

104

F in

FIG. 11

among these contacts

104

is a focus contact to which a high voltage is particularly applied in comparison with the other contacts

104

. A connecting portion

105

at one end of this focus contact is pulled out into the lower measure type housing

102

b

to reliably insulate the focus contact from the other contacts

104

.

As shown in

FIG. 13

, an end portion of the connecting portion

105

is bent in a downward U-shape. Two parallel press contact slits

106

are concavely formed in the bent portion. A connecting piece

107

a

of a focus side discharge electrode plate

107

is press-fitted into one press contact slit

106

. The press contact slit

106

is electrically connected to the focus side discharge electrode plate

107

. The focus side discharge electrode plate

107

has a center of the focus side discharge electrode plate

107

projecting in a spherical or conical shape.

The focus side discharge electrode plate

107

is attached to a side wall surrounding a discharge air gap chamber

108

formed within the box-shaped housing

102

b

(see FIG.

12

). The focus side discharge electrode plate

107

is positioned opposite to a ground side discharge electrode plate

109

similarly formed such that the focus side discharge electrode plate

107

and the ground side discharge electrode plate

109

form a discharge gap within the discharge air gap chamber

108

. This discharge gap remains quiescent while a normal voltage is applied to the focus contact

104

F. When a discharge occurs within the cathode ray tube, the discharge gap discharges spark energy of this discharge to the ground side discharge electrode plate

109

to prevent discharged electric current from flowing in the reverse direction from the focus contact

104

F to a semiconductor element within a circuit.

In

FIG. 12

, a terminal storing concave portion

111

is concavely arranged from an open face

103

on a side partitioned by a partition wall

110

from the discharge air gap chamber

108

within the box-shaped housing

102

b

. A terminal

112

is stored to the terminal storing concave portion

111

. In the terminal

112

, an external connecting portion

112

a

and a resistance connecting portion

112

b

are continuously integrated with each other. A portion of the terminal storing concave portion

111

for storing the external connecting portion

112

a

extends through a plane side of the box-shaped housing

102

b

. One end of an external lead wire

114

, having its other end connected to a flyback transformer, is inserted from the plane side into this through hole where it comes into elastic contact with an elastic contact piece

112

c

of the external connecting portion

112

a.

Similar to the end portion of the connecting portion

105

, as shown in

FIG. 13

, the resistance connecting portion

112

b

is bent in a downward U-shape. A press contact slit

116

is concavely formed in this bent portion. Both side lead portions

115

a

of the resistance element

115

are respectively press-fitted into press contact slits

116

,

106

of end portions of this resistance connecting portion

112

b

and the connecting portion

105

from the open face

103

of the box-shaped housing

102

b

. Thus, the resistance element

115

is connected in series between the focus contact

104

F and the flyback transformer.

In this connecting work, it is sufficient to press-fit both end lead portions

115

a

of the resistance element

115

to the press contact slits

116

,

106

respectively formed in the terminal

112

. The connecting portion

105

of the focus contact after the terminal

112

and the focus contact

104

F are attached into the box-shaped housing

102

b

. Accordingly, soldering is not required. Therefore, the connection is easily made.

However, it is desirable to make the CRT socket in a shape that is as compact as possible in order to accomplish high density mounting. But the conventional resistance element connecting structure

100

positions the resistance element

115

parallel to the open face

103

of the box-shaped housing

102

b

. Therefore, the space required for the resistance element

115

is enlarged in a plane direction of the box-shaped housing

102

b

and thereby interferes with the desire to make the CRT socket

101

compact.

Therefore, as shown in

FIG. 14

, a resistance element connecting structure

120

for storing the resistance element

115

in a vertical direction with respect to a box-shaped housing

121

has also been developed. In this resistance element connecting structure

120

, both end lead portions

115

a

of the resistance element

115

are press-fitted into press contact slits

124

,

124

formed in a terminal

122

. A connecting portion

123

is connected to an unillustrated focus contact. The resistance element

115

is stored toward a side of a terminal storing concave portion

125

along an attaching direction of the terminal

122

.

However, in this resistance element connecting structure

120

, the resistance element

115

is attached after the terminal

122

and the focus contact are attached from an open plane side (an upper side in

FIG. 14

) of the box-shaped housing

121

. Therefore, the lead portions

115

a

of the resistance element

115

are press-fitted to the press contact slits

124

,

124

of the terminal

122

and the connecting portion

123

from the open plane side (the upper side) using a jig. Accordingly, there is no storing space for the resistance element

115

on an inner side (lower side) onto which the terminal

122

or the focus contact is attached. Therefore, the only available storing space is located in a space between the terminal

122

and the focus contact. As a result, the CRT socket is inevitably larger to permit installation of the resistance element

115

.

Further, the positioning of the resistance element

115

in the vertical direction requires that press contact slits

124

,

124

on sides of the terminal

122

and the focus contact are close together. Therefore, it is difficult to press-fit the bent lead portions

115

a

. Further, one lead portion

115

a

of the resistance element

115

on a side connected to the connecting portion

123

must be pulled out on the inner side (lower side). Therefore, it is necessary to arrange a lead portion having an excessive length.

OBJECTS AND SUMMARY OF THE INVENTION

To solve the above problems, an object of this invention is to provide a resistance element connecting structure of a CRT socket in which a resistance element can be connected simply work, and which does not require an increase in the size of the CRT socket for connection of a resistor.

To solve the above problems, a resistance element connecting structure of a CRT socket according to the invention comprises a focus contact connected to a focus pin of a cathode ray tube; a terminal connected to an external lead wire; a focus side discharge electrode plate connected to the focus contact; a ground side discharge electrode plate; and a box-shaped housing in which a contact storing concave portion for storing the focus contact, a terminal storing concave portion for storing the terminal, and a discharge air gap chamber for oppositely arranging the focus side discharge electrode plate and the ground side discharge electrode plate spaced from each other by a discharge gap are concavely arranged from an open face on one side of the box-shaped housing; wherein a resistance element is connected in series between the focus contact attached from the open face to the contact storing concave portion and the terminal attached from the open face to the terminal storing concave portion; the focus side discharge electrode plate is formed by a metallic plate in which a spherical electrode portion is projected at a center of the metallic plate, and an elastic contact piece is projected from a bottom edge of the metallic plate in a direction reverse to a projecting direction of the electrode portion; an attaching frame portion for nipping and fixing both sides of the focus side discharge electrode plate is formed in a side wall surrounding the discharge air gap chamber of the box-shaped housing; an inside lead portion of the resistance element having an outside lead portion connected to the terminal is arranged outside the side wall; the bottom edge of the metallic plate is directed toward the interior of the box-shaped housing, and the focus side discharge electrode plate is attached to the attaching frame portion from the open face along the side wall, and the electrode portion of the focus side discharge electrode plate faces the discharge air gap chamber, and the elastic contact piece projected to an outer side from the side wall of the discharge air gap chamber comes in elastic contact with the inside lead portion of the resistance element; and the focus side discharge electrode plate connected to the focus contact is connected to the inside lead portion of the resistance element.

The elastic contact piece is projected to the bottom edge of the focus side discharge electrode plate, and this focus side discharge electrode plate is attached to the attaching frame portion. Thus, the electrode portion of the focus side discharge electrode plate faces the discharge air gap chamber, and the elastic contact piece comes in elastic contact with the inside lead portion ofthe resistance element. Accordingly, the inside lead portion of the resistance element can be electrically connected to the focus contact only by attaching the focus side discharge electrode plate connected to the focus contact.

The resistance element can be also stored into the box-shaped housing together with the attachment of the terminal. Accordingly, the outside lead portion of the resistance element can be connected to the terminal in advance before the terminal is attached to the box-shaped housing. Therefore, the outside lead portion can be easily connected and can be also connected by soldering.

A resistance element connecting structure ofthe CRT socket according to a further aspect of the invention includes a terminal that has an external connecting portion connected to the external lead wire, and a resistance connecting portion integrally and continuously arranged on a side of the external connecting portion; a resistance storing portion is continuously arranged inward along an attaching direction of the terminal from a portion of the terminal storing concave portion storing the resistance connecting portion therein; and the resistance element having the outside lead portion connected to the terminal is stored to the resistance storing portion.

It is not necessary to connect the resistance element after the terminal is attached to the box-shaped housing. Therefore, the resistance storing portion can be continuously arranged inside the terminal storing concave portion along an attaching direction of the terminal, and the resistance element can be stored to the resistance storing portion. Accordingly, the compactness of the CRT socket remains unrestricted by need to provide a storing space for the resistance element.

A resistance element connecting structure of the CRT socket in claim

3

is characterized in that the focus contact and the focus side discharge electrode plate are integrally molded by punching the metallic plate.

Since the focus contact and the focus side discharge electrode plate are integrally molded, the number of parts is not increased. Further, the inside lead portion of the resistance element can be electrically connected to the focus contact by one attaching work for attaching the focus contact and the focus side discharge electrode plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1

is a plan view of a CRT socket

2

having a resistance element connecting structure

1

of the CRT socket according to an embodiment of the present invention.

FIG. 2

is a side view of the CRT socket

2

.

FIG. 3

is a partially broken exploded side view of the CRT socket

2

.

FIG. 4

is a bottom view of the CRT socket

2

in which a base housing

3

is omitted.

FIG. 5

is a longitudinal sectional view cut in an attaching portion

26

of a terminal

11

.

FIG. 6

is a longitudinal sectional view of a terminal storing concave portion

22

cut in a direction perpendicular to that in FIG.

5

.

FIG. 7

is an exploded perspective view of a main portion of a box-shaped housing

4

.

FIGS.

8

(

a

) and

8

(

b

) are respectively plan and bottom views of the boxshaped housing

4

.

FIGS.

9

(

a

),

9

(

b

) and

9

(

c

) are respectively side, front and plan views of the terminal

11

.

FIGS.

10

(

a

),

10

(

b

) and

10

(

c

) are respectively side, plan and front views of a connecting plate

18

for integrally connecting a focus contact

8

and a focus side discharge electrode plate.

FIG. 11

is a plan view of a conventional CRT socket

101

.

FIG. 12

is a rear view of a main portion ofthe socket of

FIG. 11

from which a bottom cover

102

c

of the CRT socket

101

is removed.

FIG. 13

is a perspective view of a main portion of the socket of

FIG. 11

showing a resistance element connecting structure

100

of the conventional CRT socket.

FIG. 14

is a longitudinal sectional view of a CRT socket showing another resistance element connecting structure

120

of the conventional CRT socket.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A resistance element connecting structure

1

of a CRT socket

2

in an embodiment of the present invention will next be explained by

FIGS. 1

to

10

. A housing of the CRT socket

2

includes a base housing

3

and a box-shaped housing

4

. A front portion (an upper portion in

FIG. 1

) of the base housing

3

is cylindrical. A rear portion of the base housing

3

is box-shaped, open on its upper face. An open face is formed on a bottom face side of the box-shaped housing

4

. A contour of the box-shaped housing

4

is approximately the same as a contour along a rear inner wall of the base housing

3

. As shown in

FIG. 3

, the box-shaped housing

4

is installed from above and to the rear of the base housing

3

. Thus, engaging portions of both the base housing

3

and the box-shaped housing

4

are engaged and integrated with each other. When the engaging portions are integrated, an open face

4

a

of the box-shaped housing

4

on its bottom face side is covered by the rear of the base housing

3

.

A plurality of contacts

5

are attached to the cylindrical front portion of the base housing

3

from a bottom face side of the front portion. The contacts

5

are located on a circular circumference concentric to a cylinder on a plane side of the base housing

3

. The plurality of contacts

5

are inserted into fitting contact with respective pins of a neck portion

9

of a cathode ray tube inserted from the plane side. This provides electrical connection to these pins.

As shown in

FIG. 1

, a cylindrical rear side of the front portion is notched in a fan shape. When the box-shaped housing

4

is installed, a contact attaching portion

6

of the box-shaped housing

4

, formed in a mutual compensating shape, is fitted to this notched portion.

Two contact storing concave portions

7

(

FIGS. 3 and 7

) insulated from each other are formed in this contact attaching portion

6

. A focus contact

8

is inserted into each of the contact storing concave portions

7

.

As shown in

FIG. 1

, two focus contacts

8

are disposed into the box-shaped housing

4

in the CRT socket in this embodiment. Pairs of resistance elements

10

,

10

, terminals

11

,

11

, focus side discharge electrode plates

14

,

14

, ground side discharge electrode plates

12

,

12

, etc. are attached in left-hand and right-hand symmetric positions in

FIG. 1

in accordance with these two focus contacts

8

. Accordingly, for convenience, one resistance element connecting structure (the right-hand side in

FIG. 1

) will be explained and the other explanation is omitted here.

A contact storing concave portion

7

for storing the focus contact

8

rises and positions the focus contact

8

in parallel with the other contacts

5

attached to the base housing

3

. A peripheral portion of the contact storing concave portion

7

is sleeve shaped surrounded by a partition wall

7

a

. A bottom face (which is an upper side in FIG.

1

and is hereinafter called an open face) of the contact storing concave portion

7

is opened to attach the focus contact

8

from the open face side. The other extends through a plane side through a pin insertion hole

7

b

. This pin insertion hole

7

b

is located on the same circular circumference as a circular circumference on which the other contacts

5

are arranged. Thus, an unillustrated focus pin of the cathode ray tube connected to the CRT socket

2

is guided into the contact storing concave portion

7

.

As shown in FIG.

8

(

b

), a discharge air gap chamber

13

for discharging spark energy of the focus contact

8

is formed behind the box-shaped housing

4

. Attaching frame portions

15

a

,

15

b

for positioning and storing a focus side discharge electrode plate

14

and a ground side discharge electrode plate

12

are respectively formed in a front side wall

13

a

and a rear side wall

13

b

of the discharge air gap chamber

13

. A face of each of the attaching frame portions

15

a

,

15

b

on a side of the discharge air gap chamber

13

is notched in a U-shape from a side of the open face

4

a.

The attaching frame portion

15

a

attaching the focus side discharge electrode plate

14

thereto is formed behind the contact storing concave portion

7

. A portion between the attaching frame portion

15

a

and the contact storing concave portion

7

communicates with a storing groove

16

for positioning and storing a connecting plate

18

described later. Further, a lead positioning groove

17

for positioning and storing an inside lead portion

10

b

of a resistance element

10

is concavely formed along a front side (an outer side of the discharge air gap chamber

13

) of the front side wall

13

a

. This lead positioning groove

17

is concavely formed such that the lead positioning groove

17

crosses the storing groove

16

from a terminal storing concave portion

22

described later. The inside lead portion

10

b

crosses on a front side (the outer side of the discharge air gap chamber

13

) of the attaching frame portion

15

a

and is positioned by the lead positioning groove

17

.

As shown in FIGS.

10

(

a

)-

10

(

b

), the focus contact

8

in the contact storing concave portion

7

and the focus side discharge electrode plate

14

are integrally connected to each other by a connecting plate

18

. These elements are press-molded from the same metallic plate. The connecting plate

18

, and the connected elements begins as an elongated band shape in its longitudinal direction. The ends are bent in a downward direction perpendicular to the connecting plate

18

. The focus contact

8

and the focus side discharge electrode plate

14

are integrally formed with the connecting plate.

One portion of the focus contact

8

is a partially drawn cylindrical shape to permit it to come into elastic contact with the focus pin. Focus contact

8

is attached to the pin insertion hole

7

b

and the sleeve-shaped contact storing concave portion

7

from a side of the open face

4

b

. The focus contact

8

is located on the same axial line as the pin insertion hole

4

b.

The focus side discharge electrode plate

14

is a rectangular plate shape. An electrode portion

14

a

is struck out in a spherical shape at the center of the focus side discharge electrode plate

14

. An elastic contact piece

19

, projects slantingly downward from the bottom edge

14

(

b

) of the rectangular plate in a direction opposite to a striking-out direction of the electrode portion

14

a

. The elastic contact piece

19

is forked into two branches from the bottom edge

14

b

by a slit

19

a

cut from the center of a free end of the elastic contact piece

19

. The two branches are cantilevered. Each of the two branches of the elastic contact piece

19

comes into independent elastic contact with the inside lead portion

10

b

of the resistance element

10

. The independent contact improves contact reliability.

The focus side discharge electrode plate

14

is attached to the attaching frame portion

15

a

along the front side wall

13

a

from the open face side. While both sides of the rectangular plate are engaged with the attaching frame portion

15

a

, the focus side discharge electrode plate

14

is press-fitted and attached to the attaching frame portion

15

a

on a lower side (a front face side). When the focus side discharge electrode plate

14

is perfectly attached to the attaching frame portion

15

a

, the electrode portion

14

a

of the focus side discharge electrode plate

14

is exposed through a U-shaped notch into the discharge air gap chamber

13

. A free end of the elastic contact piece

19

reaches an inner bottom face of the lead positioning groove

17

, where it comes into elastic contact with the inside lead portion

10

b

of the resistance element

10

positioned in the lead positioning groove

17

.

In contrast to this, similar to the focus side discharge electrode plate

14

, the ground side discharge electrode plate

12

is also formed with a spherical electrode portion

12

a

projecting from the center of a rectangular plate on its side. Both sides of the rectangular plate are engaged, positioned and fixed to a rear attaching frame portion

15

b

of the discharge air gap chamber

13

. In this embodiment, a pair of other focus side discharge electrode plate

14

and other ground side discharge electrode plate

12

oppositely spaced by a discharge gap is integrally molded and attached along the rear side wall

13

b

of the discharge air gap chamber

13

.

When the focus side discharge electrode plate

14

and the ground side discharge electrode plate

12

are positioned and fixed to the attaching frame portions

15

a

,

15

b

, the electrode portions

12

a

,

14

a

formed in a mutual spherical shape face each other in the discharge air gap chamber

13

, and a discharge gap is formed between the electrode portions

12

a

and

14

a.

In this embodiment, as shown in

FIG. 4

, the discharge gap formed with respect to each of the two focus contacts

8

is formed in a radial shape from a central direction of the base housing

3

. Thus, an insulating distance between the pair of focus discharge electrode plates

14

is sufficiently secured even when the connecting plate

18

is connected to a center of the focus discharge electrode plate

14

. Accordingly, the focus contact

8

, the connecting plate

18

and the focus side discharge electrode plate

14

can be integrally molded in a left-hand and right-hand symmetric shape as in this embodiment. Thus, the same part is usable in both locations without considering left-hand and right-hand attaching positions.

As shown in FIG.

8

(

b

), a terminal storing concave portion

22

for storing the terminal

11

is concavely arranged from the open face side on a side partitioned by a circumferential wall

21

from the discharge air gap chamber

13

within the box-shaped housing

4

.

As shown in FIGS.

9

(

a

)-(

9

c

), the terminal

11

is constructed by a resistance connecting portion

23

, an external connecting portion

25

and an attaching portion

26

. The resistance connecting portion

23

is electrically connected to an outside lead portion

10

a

of the resistance element

10

arranged within the CRT socket

2

. The external connecting portion

25

is electrically connected to an external lead wire

24

(

FIG. 6

) inserted from the exterior of the CRT socket

2

. The attaching portion

26

integrally connects the resistance connecting portion

23

and the external connecting portion

25

.

The resistance connecting portion

23

is made up of a horizontal base plate

23

a

and a pair of press contact pieces

23

b

curving inward from both sides of the horizontal base plate

23

a

. Free end portions of the pair of press contact pieces

23

b

abut each other by their own elasticities in an upper portion of the horizontal base plate

23

a

in FIG.

9

. An insertion hole

23

c

for inserting the outside lead portion

10

a

of the resistance element

10

pierces the center of the horizontal base plate

23

a

. The insertion hole

23

c

guides a tip of the outside lead portion

10

a

to an abutting position between the press contact pieces

23

b.

The attaching portion

26

is constructed from a plate-shaped piece for connecting the resistance connecting portion

23

and the external connecting portion

25

in a vertical direction. Engaging claws

26

a

are formed on both sides of the attaching portion

26

, to fixedly position the terminal

11

within the terminal storing concave portion

22

.

The external connecting portion

25

is bent slantingly upward from a lower end of the attaching portion

26

, and an L-shaped flange piece

25

a

rises along a side and a tip of the external connecting portion

25

. The flange piece

25

a

reinforces the external connecting portion

25

to reinforce the external connecting portion

25

against bending that no intermediate portion ofthe external connecting portion

25

is curved. Thus, a tip of the external connecting portion

25

is vertically flexed with a lower end of the attaching portion

26

as a basic end.

Each of

FIGS. 5 and 6

shows a state in which the terminal

11

constructed in this way is stored to the terminal storing concave portion

22

.

FIG. 5

is a longitudinal sectional view cut in the attaching portion

26

of the terminal

11

.

FIG. 6

is a longitudinal sectional view of the terminal storing concave portion

22

cut in a direction perpendicular to that in FIG.

5

.

The terminal storing concave portion

22

is formed in a square sleeve shape by the circumferential wall

21

rising on the open face side from an inner bottom face side (a lower side in

FIG. 6

) of the box-shaped housing

4

. A pair of attaching grooves

21

a

is concavely formed in a vertical direction on an inner wall face of the circumferential wall

21

. The resistance connecting portion

23

of the terminal

11

is stored to the terminal storing concave portion

22

on a left-hand side in

FIG. 6

with respect to the attaching grooves

21

a

, and the external connecting portion

25

is stored to the terminal storing concave portion

22

on a right-hand side in

FIG. 6

with respect to the attaching grooves

21

a.

A lead insertion hole

27

communicates with an inner portion (a lower portion) of the terminal storing concave portion

22

for storing the external connecting portion

25

. The lead insertion hole

27

is opened to a plane side of the box-shaped housing

4

through a guide hole

27

a

. The external lead wire

24

inserted from the plane side of the CRT socket can be inserted into the terminal storing concave portion

22

through the lead insertion hole

27

.

A cylindrical resistance storing portion

28

for storing and positioning the resistance element

10

is continuously formed in the terminal storing concave portion

22

in an inner portion (a lower portion) of the terminal storing concave portion

22

for storing the resistance connecting portion

23

. The above lead positioning groove

17

communicates with an inner bottom face of the resistance storing portion

28

. The inside lead portion

10

b

of the resistance element

10

is guided to the lead positioning groove

17

.

Thus, the resistance storing portion

28

is formed in the inner portion of the terminal storing concave portion

22

, i.e., within a projecting shape of the terminal storing concave portion

22

to a plane of the box-shaped housing

4

. Accordingly, no large box-shaped housing

4

is required to form the resistance storing portion

28

. Further, since the resistance element

10

is insulated from other parts such as the contact

5

, the ground side discharge electrode plate

12

, etc. by the circumferential wall

21

for forming the terminal storing concave portion

22

, it is a separate partition wall to insulate the resistance element

10

is not needed.

As shown in

FIG. 5

, the circumferential wall

21

is notched in the lead positioning groove

17

formed in this resistance storing portion

28

. The lead positioning groove

17

extends along a front portion of the front side wall

13

a

until a portion crossing the storing groove

16

.

A method for connecting and assembling the resistance element

10

into the CRT socket having such a construction will next be explained.

The respective parts such as the resistance element

10

, the terminal

11

, etc. are attached to the box-shaped housing

4

while a side of the open face

4

a

of the box-shaped housing

4

is directed upward. Accordingly, in the explanation of an attaching process of these parts, the open face side is set to an upper side and a plane side is set to a lower side.

First, the resistance element

10

rises such that the outside lead portion

10

a

is directed upward and the inside lead portion

10

b

is directed downward. The resistance element

10

is then stored into the resistance storing portion

28

. When the resistance element

10

is stored in the resistance storing portion

28

, the outside lead portion

10

a

projects into the terminal storing concave portion

22

above the resistance storing portion

28

. The inside lead portion

10

b

is guided from a lower portion of the resistance storing portion

28

to the lead positioning groove

17

. A tip of the inside lead portion

10

b

is temporarily held in a state in which this tip crosses the storing groove

16

.

Subsequently, the terminal

11

is horizontally supported with the resistance connecting portion

23

located on an upper side of the resistance element

10

and the external connecting portion

25

located on an upper side ofthe guide hole

27

a

. While the engaging groove

26

a

of the attaching portion

26

is slid to the attaching groove

21

a

of the terminal storing concave portion

22

, the terminal

11

is press-fitted from above into the terminal storing concave portion

22

. At this time, the outside lead portion

10

a

of the resistance element

10

is inserted into the insertion hole

23

c

of the resistance connecting portion

23

and is nipped between the press contact pieces

23

b.

Accordingly, when the terminal

11

is fully inserted into the terminal storing concave portion

22

, the engaging claw

26

a

is engaged with the attaching groove

21

a

and is fixed into the terminal storing concave portion

22

. Further, the terminal

11

and the outside lead portion

10

a

of the resistance element

10

are electrically connected to each other. As shown in

FIG. 6

, a tip of the external connecting portion

25

makes elastic contact with an inner wall face of the terminal storing concave portion

22

above the guide hole

27

a

by elasticity of this tip.

After the terminal

11

is attached, the connecting plate

18

integrating the focus contact

8

and the focus side discharge electrode plate

14

with each other is attached to the box-shaped housing

4

.

In this attachment, while the focus contact

8

is aligned within the contact storing concave portion

7

, the focus side discharge electrode plate

14

is press-fitted downward along the front side wall

13

a

until both sides of the rectangular plate of the focus side discharge electrode plate

14

are engaged with the attaching frame portion

15

a

and are thereby fixedly positioned.

When the connecting plate

18

is perfectly attached to the attaching frame portion

15

a

, the connecting plate

18

is positioned and stored to the storing groove

16

. The focus contact

8

lies above the pin insertion hole

7

b

. Further, the electrode portion

14

a

of the focus side discharge electrode plate

14

is exposed from the U-shaped notch into the discharge air gap chamber

13

. A free end of the elastic contact piece

19

comes into elastic contact with the inside lead portion

10

b

of the resistance element

10

positioned in the lead positioning groove

17

. Thus, the inside lead portion

10

b

of the resistance element

10

is connected to the focus contact

8

through the focus side discharge electrode plate

14

, and the resistance element

10

is connected in series between the focus contact

8

and the terminal

11

.

Thereafter, a peripheral portion of the rectangular plate of the ground side discharge electrode plate

12

is fitted to the attaching frame portion

15

b

on a rear face of the discharge air gap chamber

13

so that the ground side discharge electrode plate

12

is attached. Further, a discharge gap is formed within the discharge air gap chamber

13

such that the focus side discharge electrode plate

14

and the ground side discharge electrode plate

12

are opposed to each other in the discharge gap.

After the respective parts are attached to the box-shaped housing

4

, plural contacts

5

are attached to the base housing

3

. As shown in

FIG. 3

, the box-shaped housing

4

is stored to a rear portion of the base housing

3

, and engaging portions of the base housing

3

and the box-shaped housing

4

are engaged and integrated with each other.

The CRT socket having the respective parts assembled in this way is mounted onto a printed wiring board within a television receiver. Thereafter, one end of the external lead wire

24

connected to a flyback transformer is inserted from the lead insertion hole

27

opened to the plane side of the box-shaped housing

4

. A tip of the external lead wire

24

inserted from the lead insertion hole

27

is inserted into the terminal storing concave portion

22

through the guide hole

27

a

, and is nipped between an inner wall face of the terminal storing concave portion

22

and the external connecting portion

25

.

Accordingly, the resistance element

10

is connected in series between the focus contact

8

and the external lead wire

24

having one end connected to the flyback transformer.

The present invention is not limited to the above embodiment, but can be variously modified. For example, the box-shaped housing

4

may be also integrated with the base housing

3

by separately preparing a cover body for covering an open face. Further, the open face side of the box-shaped housing

4

may be also set to a connecting face side with the CRT by setting a shape of the focus contact

8

to a reverse shape on upper and lower sides.

The focus contact

8

and the discharge electrode plate

14

are integrally molded. However, it is not always necessary to integrally mold these parts if these parts are attached to the box-shaped housing

4

and are then electrically connected to each other.

Further, in the above embodiment, the resistance element

10

is inserted into the resistance storing portion

28

before the attachment of the terminal

11

. However, the outside lead portion

10

a

may be also connected to the resistance connecting portion

23

of the terminal

11

in advance, and the resistance element

10

may be also attached into the box-shaped housing

4

together with the attachment of the terminal

11

.

The present invention can be also applied to a case in which the resistance element is connected to a CRT socket having only one focus contact instead of the CRT socket of a double focus type as in this embodiment.

In accordance with the invention, the inside lead portion

10

b

of the resistance element

10

can be electrically connected only by attaching the focus side discharge electrode plate so that electric connection to the focus contact

8

is very facilitated.

Further, there are no works in which a lead portion bent within a narrow space of the CRT socket is press-fitted and soldered. Accordingly, the resistance element

10

can be simply connected.

In accordance with the invention, in addition to the embodiment in the preceding paragraphs, the resistance storing portion

28

is continuously arranged in an inner portion of the terminal storing concave portion along an attaching direction of the terminal

11

. Accordingly, the resistance storing portion

28

for storing the resistance element

10

can be formed by utilizing a vacant space within the CRT socket.

In accordance with the invention, in addition to the invention of the foregoing paragraphs, the focus contact

8

and the focus side discharge electrode plate

14

are integrally molded. Accordingly, no electric connecting process is required between the focus contact

8

and the focus side discharge electrode plate

14

. Further, the number of parts is not increased, and an attaching work of the focus contact

8

and the focus side discharge electrode plate

14

to the box-shaped housing

4

can be simplified.

Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.

Number	Name	Date	Kind
3916238	Suzuki	Oct 1975	A
5087212	Hanami	Feb 1992	A
5094628	Kano	Mar 1992	A

Resistance element connecting structure of CRT socket

Information

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Date Filed

Date Issued

Inventors

Original Assignees

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CPC

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Abstract

Description

Claims

Priority Claims (1)

US Referenced Citations (3)