A P-F connector structure for a cathode-ray tube

Abstract: A P-F connector establishing electrical connection between a conducting layer formed on the inside wall of the funnel and a fluorescent layer formed on the inside wall of the panel is disclosed. The P-F connector comprises a fixed portion (20A) having a through hole (20D); the first connecting portion (20B) extended from one side of said fixed portion (20A) and bent, to be electrically connected to said conducting layer; and the second connecting portion (20C) extended from the same side of said fixed portion and bent in the opposite direction from said first connecting (20B) portion to be electrically connected to said fluorescent layer.

Description: The invention relates to a P-F connector for electrically connecting a conductive layer formed on the inside of a funnel and a fluorescent layer formed on the inside wall of a panel. Generally, a cathode-ray tube consists of a neck having an electron gun mount assembly and a body having a viewing screen. The body has a panel and a funnel. A conductive layer is formed on the inside wall of the funnel and a fluorescent layer is formed on the inside wall of the panel. The funnel has an anode terminal a high voltage is applied to. The fluorescent layer inside the panel should be electrically connected to the conductive layer inside the funnel. The P-F connector is mounted on a mask frame so that the fluorescent layer of the panel is electrically connected to the conductive layer of the funnel. A frame holder is welded to the mask frame, and on one end of the frame holder is mounted a holder pin. The conductive layer on the lower portion of the holder pin is manually coated by a paint-brush so that the fluorescent layer of the panel can be connected to the frame holder. Hence, a high voltage applied to the anode terminal is transmitted to the fluorescent layer of the panel by means of the conductive layer of the funnel, the P-F connector, the mask frame, the frame holder and the conductive layer on the lower portion of the holder pin. By the prior manner of applying the high voltage of the anode terminal to the fluorescent layer of the panel the conductivity of the fluorescent layer is reduced, thereby deteriorating the quality of the viewing screen. Also, because the conductive layer on the lower portion of the holder pin is manually coated by a paint-brush, the process of manufacturing a cathode-ray tube is complicated. Another known type of P-F connector (US-A-3796903) has a three-element structure comprising a pair of leaf springs as connecting elements, which are secured by welding or brazing to opposite faces of a metal piece. An object of the present invention is to provide a P-F connector of the above-mentioned type which while assuring high electric performance can be manufactured and assembled in an easy manner with little costs. Another object of the invention is to provide a P-F connector for a cathode-ray tube in which the fluorescent layer of the panel is directly connected to the conductive layer of the funnel. Still another object of the invention is to simplify the fabrication process of a cathode-ray tube by omitting a coating process of a conductive layer on the lower portion of a holder pin. The P-F connector according to the present invention for electrically connecting a conductive layer formed on the inside wall of a funnal and a fluorescent layer formed on the inside wall of a panel, comprising a mounting portion and a pair of connecting portions bent from the mounting portion in opposite directions for electrically contacting a respective one of said inside walls, is characterized in that said connecting portions being formed of an elongated part integral with one side edge of said mounting portion and divided in the longitudinal direction, such that said connecting portions (20B, 20C) can be bent in opposite directions. Pursuant to a preferred embodiment of the invention for facilitating the assembly in a cathode-ray tube the mounting portion can include a through hole for receiving a mounting clip. Further one of the connecting portions can be thinner than the other connecting portion. To better understand the nature and object of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings in which: FIG. 1 is an exploded perspective view of an embodiment of the prior art; FIG. 2 is a sectional view, partly in cross-section of an embodiment of the prior art; FIG. 3 is an exploded perspective view of an embodiment of the present invention; FIG. 4 is a sectional view, partly in cross-section of an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION FIG. 1 is an exploded perspective view of an embodiment of the prior art. As shown in FIG. 1 , a shadow mask 12 is welded to a mask frame 2 having the first through hole 2A . The P-F connector 1 having the second through hole 1A and a connecting portion 1B is inserted between the mask frame 2 and the inner shield 3 having the third through hole 3A. A fixed pin 4 is inserted into the third through hole 3A, the second through hole 1A and the first through hole 2A, thereby combining the P-F connector 1 , the mask frame 2 and the inner shield 3 together. FIG. 2 is a sectional view, partly in cross-section of the prior art. A sectional view taken along the line A-A of the FIG. 1 is included in FIG. 2 . As shown in FIG. 2 , the first conducting layer 6 is formed on the inside wall of the funnel 5 , and the connecting portion 1B of the P-F connector 1 is electrically connected to the first conducting layer 6 . Also a fluorescent layer 8 is formed on the inside wall of the panel 7 and on the lower portion of the funnel 5 , and a holder pin 10 is mounted on the lower portion, on which the fluorescent layer 8 is formed. One side portion of the frame holder 9 is welded to the mask frame 2 , and another side portion thereof is fixed to the holder pin 10 . To establish electrical connection between the frame holder 9 and the fluorescent layer 8 , the second conducting layer 11 is made by coating the lower portion of the holder pin 10 . Hence, the high voltage applied to an anode terminal(not shown) is transmitted to the fluorescent layer 8 by way of the connecting portion 1B of the P-F connector 1 , the mask frame 2 , the frame holder 9 and the second conducting layer 11 . FIG. 3 is an exploded perspective view of an embodiment of the present invention. The construction of FIG. 3 is identical to that of FIG. 1 except the feature of the P-F connector. As shown in FIG. 3 , a P-F conductor 20 is inserted between the inner shield 3 and the mask frame 2 , and comprises a fixed portion 20A having the third through hole 20D, the first connecting portion 20B bent to a desired degree and extended from one side of the fixed portion 20A , and the second connecting portion 20C bent in the opposite direction from the first connecting portion 20B , extended from the same side of the fixed portion 20A . FIG. 4 is a sectional view, partly in cross-section of an embodiment of the present invention. A sectional view taken along the line A-A of the FIG. 3 is included in FIG. 4 . As shown in FIG. 4A , one end of the first connecting portion 20B of the P-F connector 20 is electrically connected to the first conducting layer 6 , and the second connecting portion 20C thereof is electrically connected to the fluorescent layer 8 . Thus the high voltage applied to an anode terminal(not shown) is transmitted to the fluorescent layer 8 through only the P-F connector 20 i.e., the first connecting portion 20B and the second connecting portion 20C. However, the fluorescent layer 8 can be easily scratched, and the conductivity between the second connecting portion 20C and the fluorescent layer 8 decreases if the fluorescent layer 8 is scratched by the second connecting portion 20C. The second connecting portion 20C , therefore should be made thin and smooth in order not to scratch the fluorescent layer 8 . Therefore, the present invention makes the process of making cathode-ray tubes simple by fixing the inner shield to the mask frame with a pin instead of welding and by saving the coating process of the conducting layer for the electrical connection of the fluorescent layer and the frame holder.

Claims: A P-F connector for electrically connecting a conductive layer formed on the inside wall of a funnal and a fluorescent layer formed on the inside wall of a panel, comprising a mounting portion (20A) and a pair of connecting portions (20B,20C) bent from the mounting portion in opposite directions for electrically contacting a respective one of said inside walls, characterized in that said connecting portions (20B,20C) being formed of an elongated part integral with one side edge of said mounting portion (20A) and divided in the longitudinal direction, such that said connecting portions (20B, 20C) can be bent in opposite directions. The P-F connector as claimed in claim 1 wherein said mounting portion (20A) further including a through hole (20D) for receiving a mounting clip (4). The P-F connector as claimed in claim 1 wherein one of said connecting portions (20C) is thinner than the other connecting portion (20B).

Inventors: CHUN SE-KI, CHUN, SE-KI
Applicants: ORION ELECTRIC CO LTD, ORION ELECTRIC CO., LTD.
Application year: 1993
Main classification: H01J29
IPC codes: H01J29