Abstract:
A cathode ray tube (CRT) receiving socket includes a body having a plurality of connection holes for receiving the pins of a CRT, a plurality of conductive pins protruding from the body in a certain direction for connection to a printed circuit board (PCB), and an insulation rib formed between a pin to which a high voltage is applied and a neighboring pin. The insulation rib protrudes from one side of the body in the same direction as that of the pins, and is integral with the body in the CRT receiving socket, into which a plurality of pins extending from one end of the CRT is inserted.

Description:
CLAIM OF PRIORITY 
     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from my application CRT RECEIVING SOCKET WITH INSULATING RIB AND MONITOR COMPRISING THE SAME filed with the Korean Industrial Property Office on May 23, 2000 and there duly assigned Ser. No. 27803/2000 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a cathode ray tube (CRT)receiving socket for a monitor and, in particular, to a CRT receiving socket fixed at a video printed circuit board (PCB) for transferring an electrical signal to the CRT. 
     2. Related Art 
     Generally, the monitor is an apparatus capable of outputting electric beams from an electric gun of a CRT based on a video signal, and emitting light as the emitted electric beams are outputted onto a fluorescent material coated on a front surface of the CRT to thereby display a certain character, symbol and graphic. 
     Contemporary monitors are typically provided with a CRT receiving socket having pins which are subjected to high voltage, and this results in signal distortion. Moreover, such monitors employ an arrangement for preventing high voltage from being transferred from certain pins to other pins. This arrangement includes through grooves and insertion holes, but these grooves and holes are susceptible to the collection of dust and other foreign matter, especially in view of the high voltages involved. Thus, the insulation effect normally provided deteriorates. As a result, the diplay of the monitor can become unclear. 
     Therefore, there is a need for a CRT receiving socket which is not burdened by the aforementioned disadvantages. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a CRT receiving socket having an insulation rib and a monitor having the same which overcome the problems encountered in prior systems. 
     It is another object of the present invention to provide a CRT receiving socket having an insulation rib and a monitor having the same which are capable of enhancing the insulation between a PCB, to which a high voltage is applied, and the parts mounted on the PCB. 
     It is another object of the present invention to provide a CRT receiving socket having an insulation rib and a monitor having the same which are capable of preventing the problem of an unclear display by increasing the voltage applied to the G2 pin of the CRT. 
     It is another object of the present invention to provide a CRT receiving socket having an insulation rib and a monitor having the same which are capable of integrally forming a member capable of enhancing an insulation effect of a video PCB with a body. 
     To achieve the above objects, there is provided a CRT receiving socket into which a plurality of pins protruding from one end of a CRT are inserted, the socket comprising a body having a plurality of connection holes for receiving the pins of the CRT, a plurality of conductive pins protruding from the body in a certain direction for connection to the PCB, and an insulation rib formed between a pin to which a high voltage is applied and a neighboring pin among the plurality of the pins, and protruding from one side of the body in the same direction as that of the pins, and being integral with the body. 
     The shape of the insulation rib may be varied. For example, the insulation rib may have the same height as that of the conductive pin, and may have a height which is half that of the conductive pin. In this case, the height of the insulation pin is properly determined in such a manner that a foreign substance is not gathered in a through groove or hole, thereby decreasing an insulation effect. In addition, each insulation rib may have an arc shape, and may be provided between a pin, to which a high voltage is applied, and a neighboring pin. 
     Preferably, the pin to which a high voltage is applied is connected with the G2 pin of the CRT. Among the pins of the CRT, the pin to which a high voltage is applied is a G2 pin. About 600 to 800 volts is applied thereto. An insulation rib is formed at a portion around the pin of the CRT receiving socket connected with the G2 pin. 
     A through groove or hole having the same cross section as the insulation rib is formed on the PCB connected with the CRT receiving socket. When the CRT receiving socket is assembled to the PCB, it is possible to prevent foreign substances from gathering in the through groove or hole, thereby decreasing an insulation effect. 
     To achieve the above objects, there is provided a monitor having a CRT, a casing surrounding the CRT, and a PCB connected to a rear portion of the CRT. In the monitor according to the present invention, the CRT is inserted into the CRT receiving socket on the PCB, a plurality of pins protrude from one surface of the CRT receiving socket for electrical connection with the PCB, an insulation rib protrudes in the same direction as the pin, and at a portion of the pin among the pins to which a high voltage is applied, and a through groove or hole having the same cross section as the insulation rib is formed on the PCB, whereby the insulation rib is inserted into the through groove or hole when the CRT receiving socket is assembled to the PCB. 
     The pin to which a high voltage is applied is connected to a G2 pin of the CRT. 
     The rib is integral with the body of the CRT receiving socket. In the present invention, the fabrication cost of the PCB and other parts of the monitor is not increased. 
     Additional advantages, objects and features of the invention will become more apparent from the description which follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
     FIG. 1 is a view illustrating an exploded perspective view illustrating a monitor; 
     FIG. 2 is an exploded perspective view illustrating an engaged state of a CRT and a video PCB; 
     FIG. 3 is an exploded perspective view illustrating a state in which a CRT receiving socket is engaged to a video PCB; 
     FIG. 4 is a perspective view illustrating an engaged state of a G2 pin of a CRT in the video PCB of FIG. 3; 
     FIG. 5 is an exploded perspective view illustrating a state in which a CRT receiving socket is mounted on a video PCB according to a first embodiment of the present invention; 
     FIG. 6 is a partially enlarged view illustrating an engaged state of a G2 pin of a CRT in the CRT receiving socket of FIG. 5; 
     FIG. 7 is a partially enlarged view illustrating an engaged state of a G2 pin in the video PCB of FIG. 5; 
     FIG. 8 is an exploded perspective view illustrating a state in which a CRT receiving socket is mounted on a video PCB according to a second embodiment of the present invention; 
     FIG. 9 is a partially enlarged view illustrating an engaged state of a G2 pin of a CRT in the CRT receiving socket of FIG. 8; 
     FIG. 10 is an exploded perspective view illustrating a state in which a CRT receiving socket is mounted on a video PCB according to a third embodiment of the present invention; 
     FIG. 11 is a partially enlarged view illustrating an engaged state of a G2 pin of a CRT in the CRT receiving socket of FIG. 10; and 
     FIG. 12 is a partially enlarged view illustrating an engaged state of a G2 pin of the video PCB of FIG.  10 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is a view illustrating the construction of a monitor. As shown therein, the monitor includes a front casing  3  and a rear casing  15  which form an outer structure, a CRT  7  installed between the front casing  3  and the rear casing  15 , a video PCB assembly  11  installed behind the CRT  7 , an operation unit  5  installed below an inner portion of the front casing  15 , a main PCB  17  connected with the operation unit  5  and the video PCB assembly  11 , and an electric wave shield  13  installed between the rear casing  15  and the CRT  7 . The CRT  7  is fixed at the front casing  3  by a certain member, such as a screw  9 . The main PCB  11  externally receives and processes a video signal, and transfers the processed signal to the video PCB assembly  11 , and the video PCB  11  transfers an analog signal to the CRT  7 . 
     FIG. 2 is a view illustrating the video PCB assembly  11  and the CRT  7  of FIG.  1 . The video PCB assembly  11  includes a video PCB  25 , a front shield  27  which surrounds the front portions of the video PCB  25 , and a rear shield  29  which surrounds the rear portions of the video PCB  25 . The front shield  27  and the rear shield  29  prevent the electrical waves from being outputted from the video PCB  25 . An electrical gun  18  is installed behind the CRT  7 , and a plurality of pins  20  connected with the video PCB  25  protrude backwardly from the electric gun  18 . The protruding pins  20  are inserted into connection holes  23  of a CRT receiving socket  21  installed on the video PCB  25 . The video PCB  25  is connected with the main PCB  17  through a plurality of signal lines(not shown). 
     FIG. 3 is a view illustrating a state wherein the CRT receiving socket  21  of FIG. 2 is separated from the video PCB  25 . A plurality of pins  51 ,  53 ,  55 , . . . ,  69  protrude from a rear portion  71  of the CRT receiving socket  21 , and the pins  51 ,  53 ,  55 , . . . ,  69  are inserted into insertion holes  31 ,  33 , . . . ,  49  formed at the video PCB  25 , and are fixed thereto by a welding method. The CRT receiving socket  21  is formed of a plastic material having good insulation. Among the pins of the CRT receiving socket  21 , a high voltage of 600 to 800 volts is applied to the pin  59  connected with the G2 pin of the CRT  7 . Therefore, the signals may be distorted at a portion around the pin  59  of the CRT receiving socket  21  due to a high voltage. Furthermore, the through grooves  200  and  202  are formed at a portion around the insertion hole  39  into which the pin  59  is inserted for preventing a high voltage of the pin  59  from being applied to the pins  57  and  61 . 
     FIG. 4 is a view illustrating the construction of the through grooves  200  and  202 . As shown in FIG. 4, the first through groove  200  includes a vertical groove  203 , a first horizontal groove  204  connected therewith, and a second horizontal groove  205  extending from the first horizontal groove  204 . In addition, the second through groove  202  includes a vertical groove  206  and a horizontal through groove  207 . The shapes of the through grooves  200  and  202  are such that the installations of the parts mounted on the PCB  25  and signals lines do not interfere with each other. 
     However, even when the through grooves  200  and  202  are formed on the PCB  25 , foreign substances can become attached to the portions around the insertion hole  39 . A part of the foreign substances may be moved into the through grooves  200  and  202 . In particular, since a high voltage is applied to a portion around the G2 pin, a lot of dust can become attached thereto, and the through grooves  200  and  202  can become filled with the dust so that the insulation effect of the through grooves  200  and  202  is decreased. As a result, since a G2 voltage lower than the initial voltage is applied to the CRT  7 , the display of the monitor becomes unclear. The above-described problem may cause a malfunction of the monitor. 
     FIG. 5 is a view illustrating a first embodiment of a CRT receiving socket  21  corresponding to a video PCB  25  according to the present invention. As seen in FIG. 5, each of a pair of insulation ribs (protrusions)  91  and  93  has an arc-shaped cross section at a portion around the pin  59  connected to a G2 pin of the CRT, and each has the same height as that of the pin  59  and is formed between a pin  61  and a pin  57 . The insulation ribs or protrusions  91  and  93  protrude perpendicularly from a surface  71  opposite to the video PCB  25 . 
     FIG. 6 is a partially enlarged view illustrating a pin  59  in the CRT receiving socket  21 . Ribs  91  and  93 , which surround the pin  59 , protrude between the pins  59  and  61  and the pins  57  and  59 , respectively. The heights H1 of the ribs or protrusions  91  and  93  are the same as that of the pin  59 , and each of the ribs or the protrusions  91 ,  93  has a thickness of t 1 . The insulation ribs  91  and  93  are formed in such a manner that the pin  59  is placed at the inner portions  97  and  95  of the insulation ribs  91  and  93 , respectively. 
     FIG. 7 is a partially enlarged view illustrating a portion surrounding the insertion hole  39  into which the pin  59  of the CRT receiving socket  21  is inserted in the video PCB  25  of FIG.  5 . An arc-shaped through groove  300  is formed between the insertion holes  37  and  39 . A through hole  302  corresponding to the arc shape through groove  300  is formed between the insertion holes  39  and  41 . The above through grooves each have a thickness of t 2  in the radial direction. The thickness t 2  may be the same as t 1 . For an easier assembly, t 2  is slightly larger than t 1 . 
     FIG. 8 is a view of a second embodiment of the video PCB  25  and the CRT receiving socket  21  according to the present invention. In the present invention, the heights of insulation ribs  101  and  103  protruding from a surface  71  of the CRT receiving socket  21  are lower than those in the first embodiment of the present invention. FIG. 9 illustrates the construction of the insulation ribs  101  and  103  of the second embodiment of the present invention. The height H2 of the protrusion is one half the height of the pin  59  and has a thickness t 3 . The insulation ribs  101  and  103  are formed in such a manner that the pin  29  is placed in the directions of the inner surfaces  105  and  107  of the insulation ribs  101  and  103 . Therefore, it is possible to prevent any damage to the insulation ribs when assembling the system by decreasing the heights H2 of the insulation ribs  101  and  103 . However, if the heights H2 of the insulation ribs  101  and  103  are small so that the through holes  300  and  302  are not properly filled, certain foreign substances, such as dust, may enter the through grooves  300  and  302 . Therefore, an exaggerated decrease in the heights of the insulation ribs  101  and  103  is not needed. 
     FIG. 10 is a view of a third embodiment of the video PCB  25  and the CRT receiving socket  21  according to the present invention. In the third embodiment of the present invention, the insulation ribs  401  and  403  each have a rectangular shaped cross-section compared to the first and second embodiments of the present invention, in which each of the insulation ribs  91 ,  101  and  93 ,  103  has an arc-shaped cross section. FIG. 11 is a partially enlarged view illustrating the portions of the pin  59  in the CRT receiving socket  21  according to the third embodiment of the present invention. As shown therein, an insulation rib  401  having a rectangular cross section, a certain thickness t 4 , and a height of H3 is formed between the pins  59  and  61  of the CRT receiving socket  21 , and an insulation rib  403  formed of a rectangular portion  405  parallel to the insulation rib  401  and a rectangular portion  407  extending from the rectangular portion  405  at an angle of 60 degrees are formed between the pins  57  and  59 . 
     FIG. 12 is a partially enlarged view of a video PCB  25  having through grooves or holes  301  and  303  corresponding to the insulation ribs  401  and  403 . The through groove  301  of the video PCB  25 , according to the third embodiment of the present invention, has a rectangular cross section having a thickness of t 5 . The through groove  303  formed between the insertion hole  39  and the insertion hole  37  is formed of a portion  305  parallel to the through groove  301 , and a portion  307  which is upwardly extending from the portion  305 . The thickness t 5  is slightly larger than thickness t 4  for an easier insertion of the insulation rib. 
     The front view of the construction in which the CRT receiving socket  21  is mounted on the video PCB  25  is the same as that of FIG. 2, which illustrates that the CRT receiving socket  21  is engaged. The CRT receiving socket  21  is fixedly mounted on the video PCB  25  by welding. The monitor according to the present invention includes a front casing  3  and a rear casing  15  which form an outer structure of the monitor, a CRT  7  installed therebetween, a video PCB assembly  11  installed behind the CRT  17 , an operation unit  5  installed below the front casing  15 , a main PCB  17  connected to the operation unit  5  and the video PCB assembly  11 , and an electric wave shield  13  installed between the rear casing  15  and the CRT  17  in the same manner as in the monitor described previously. 
     In the present invention, it is assumed that a high voltage is applied to one pin. The insulation rib may be formed with respect to all pins, thereby enhancing an insulation effect. In addition, the shapes of the insulation rib and the through hole may be changed in such a manner that the shapes of the same do not interfere with the neighboring parts and the signal lines. 
     In the present invention, it is possible to prevent an unclear display of the screen and malfunction which occur in the prior monitors since, in the invention, foreign substances do not attach themselves to a portion of the G2 pin to which a high voltage is applied, as compared to prior monitors. In addition, the fabrication cost of the CRT receiving socket according to the present invention is not higher than that of the prior CRT receiving socket. It is possible to prevent a foreign substance, such as dust, from hampering the insulation of the PCB, and thereby decreasing the insulation effect. 
     Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible without departing from the scope and spirit of the invention, as recited in the accompanying claims.