Abstract:
A monitor housing has a front casing connected with a rear casing enclosing a cathode ray tube. The front casing has at least one snap portion at an upper rear surface of the same and at least one engaging pin at a lower rear surface. The rear casing has at least one engaging portion at an upper front surface for being detachable engaged with the front casing. At least one receiving hole is formed at a lower portion of the front surface, so that the rear casing is integrally engaged with the front casing in such a manner that the receiving hole is separately engaged to the engaging pin, and a snap pin engaged in the receiving hole for preventing the engaging pin from detaching from the receiving hole in the case that the engaging pin of the front casing is integrally engaged into the receiving hole of the rear casing for thereby significantly decreasing an assembling time with an easier assembling and disassembling operation of a front casing and a rear casing and enhancing an engaged state of the monitor.

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 an application entitled  Assembling Structure of Monitor Case  earlier filed in the Korean Industrial Property Office on 13 Feb. 1999, and there duly assigned Ser. No. 99-5277 by that Office and an application entitled  Assembling Structure of Monitor Case  earlier filed in the Korean Industrial Property Office on 13 Feb. 1999, and there duly assigned Ser. No. 99-5285 by that Office. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a monitor, and in particular to a monitor having a detachable engaging structure adapted to a monitor casing formed of a front casing stably engaging to a rear casing. 
   2. Description of the Background Art 
   Generally, a monitor is capable of emitting an electron beam from an electron gun of a cathode ray tube toward a fluorescent material coated on the cathode ray tube based on an image  21  signal for generating different bright and color lights, so that it is possible to form a certain character, symbol, graphic, or other visual display. 
   The monitor includes a casing for protecting the inner structure including components such as the cathode ray tube (CRT), CRT control circuits, and power supplies from an external impact. The casing is formed of a front casing and a rear casing that are engaged by fasteners such as screws. 
   In the conventional engaging structure of the monitor casing, when engaging the rear casing to the front casing, the engaging positions of the screw and the hole must be accurately aligned, so that accurate work is required. In addition, during the engaging process, the front and rear casings must be manually engaged using a certain tool, so that the entire assembling process takes a long time. In addition, since the assembling and disassembling processes are repeatedly performed, the hole for the screw may be enlarged, so that it is impossible to implement a stable engagement between the front casing and the rear casing of the monitor. 
   An exemplar of the art, Helgeland (U.S. Pat. No. 4,662,797 , Adaptable Housing for a Video Terminal , May 5, 1987) discloses fasteners such as screws to attach the front casing with the rear casing. Other exemplar art are Douken et al. (U.S. Pat. No. 5,793,494 , CRT Display Device , Aug. 11, 1998), Lundgren et al. (U.S. Pat. No. 5,870,485 , Computer Visual Display Monitor with Integral Stereo Speaker and Directional Microphone and Method for Construction , Feb. 9, 1999), Fazioli (U.S. Pat. No. 4,651,218 , Method and Apparatus for Mounting a CRT in a Dynamic  ( Vibration and Shock Prone )  Environment , Mar. 17, 1987), Leo et al. (U.S. Pat. No. 5,084,757 , Method and Apparatus for Mounting a Cathode Ray Tube to Minimize Tube Shift and Respect to a Bezel , Jan. 28, 1992), and Lo (U.S. Pat. No. 5,122,928 , Monitor Housing , Jun. 16, 1992). 
   SUMMARY OF THE INVENTION 
   It is therefore, an object of the present invention to provide a monitor casing capable of significantly decreasing the assembly time by having an easier assembling and disassembling operation of the front and rear casing. 
   It is another object to enhance the engaging state of the monitor. 
   It is a further object to avoid damage to the monitor housing while assembling and disassembling the monitor case multiple times. 
   It is yet another object to need less precision in assembling the monitor housing. 
   It is still a further object to allow easy and quick access to the internal parts of a monitor. 
   To achieve the above objects, there is provided a monitor having a cathode ray tube encased within a housing formed by engaging the front casing with a rear casing. The front casing has at least one snap portion at the upper rear surface and at least one engaging pin at the lower rear; A rear casing has at least one engaging portion at an upper front surface that detachably engages with the front casing. At least one receiving hole is formed at a lower portion of the front surface, so that the rear casing is integrally engaged with the front casing in such a manner that the receiving hole is separately engaged to the engaging pin, and a snap pin engaged in the receiving hole for preventing the engaging pin from disconnecting from the receiving hole in the case that the engaging pin of the front casing is integrally engaged into the receiving hole of the rear casing. 
   The snap portion has an elastic plate formed by cutting away a part of the inner structure of the snap portion, a rectangular engaging hole formed at an intermediate portion of the elastic plate and a slant surface formed at one end of the snap portion at a certain angle. The engaging portion includes an engaging shoulder portion fixed by an engaging hole of the snap portion and a pair of guides formed in both directions of the engaging shoulder portion, thus allowing the engaging portion to be stably engaged with the snap portion. 
   The distance between the guides is larger than the width of the snap portion, and both sides of the snap portion contact with the inner surfaces of the guides. The heights of the guides are lower than the height of the engaging shoulder portion, and the lengths of the guides are shorter than the length of the engaging shoulder portion. When the front and rear casing are integrally engaged, a certain gap is formed between the front and rear casings, so that a certain tool such as a driver is inserted into the gap when disassembling the front and rear casings. 
   The engaging pin is a rectangular bar, and a pair of reinforcing shoulder portions are formed at the upper end of the engaging pin, and an engaging portion is formed at an end portion of the lower surface of the engaging pin. A cut-away groove is formed at the top portion of the receiving hole, and a fixing hole is formed at a portion backwardly distanced from the cut-away portion, and a pair of engaging shoulder portions each having a slant surface are formed at the bottom portion, and the engaging portion of the engaging pin is engaged and disconnected with the engaging shoulder portions. 
   The snap pin includes a polygonal upper body, a lower body formed at a lower portion of the upper body and having one end divided into first and second members, and a connection portion for integrally connecting the upper and lower bodies. An engaging protrusion is downwardly protruding from one end of the upper body and is fixed at a fixing hole of the top portion. The width of the lower body is smaller than the distance between the reinforcing shoulder portions and is received between the reinforcing shoulder portions when the first and second members are aligned in the center direction of the shoulder portions. 
   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 this 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 disassembled perspective view illustrating an engaging structure of a monitor casing; 
       FIG. 2  is an enlarged cross-sectional view illustrating upper and lower engaging structures of a monitor casing; 
       FIG. 3  is a disassembled perspective view illustrating an engaging structure of a monitor casing according to the present invention; 
       FIG. 4  is a perspective view illustrating an upper engaging structure of a front casing and a rear casing of a monitor according to the present invention; 
       FIGS. 5A–5C  illustrate an engaged state of the upper portions of a front casing and a rear casing of  FIG. 4 ; 
       FIG. 6  is a perspective view illustrating the portion C of  FIG. 3 ; 
       FIG. 7  is a perspective view illustrating the portion D of  FIG. 3 ; 
       FIG. 8  is a cross-sectional view illustrating a lower engaging portion of a front casing and a rear casing according to the present invention; 
       FIG. 9  is an enlarged cross-sectional view illustrating the portion F of  FIG. 8 ; and 
       FIG. 10  is a cross-sectional view taken along line E—E of  FIG. 9 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Turning now to the drawings of  FIGS. 1 and 2 , the monitor  1  includes a front casing  2 , a cathode ray tube  3  engaged to the back of the front casing  2 , and a rear casing  4  integrally engaged with the front casing  2 . A receiving groove  8  is formed at each corner portion of the back of a rim portion  6 . In addition, a through hole  9  through which an engaging screw  7  passes is formed at each corner portion of the rear casing  4 . 
   The engaging screw  7  is engaged into the receiving groove  8  of the front casing through the hole  9  of the rear casing  5 , so that the front and rear casings  2  and  4  are integrally engaged. When disassembling the front and rear casings  2  and  4 , the engaging screw  7  is loosened using a certain tool such as a driver or other similar tools. 
   Referring to  FIG. 3 , a monitor  50  includes a front casing  51 , a cathode ray tube  52  engaged to the back of the front casing  51 , and a rear casing  53  integrally engaged with the front casing  51  for protecting the inner elements of the monitor from an external impact. 
   A plurality of snap portions (or indent portions)  60  are backwardly protruded from the upper portion of the back of the front casing  51 . In addition, a plurality of engaging portions  70 ( FIG. 4 ) are formed at the front upper portion of the rear casing  53 . Therefore, the engaging portions  70  are engaged to the snap portions  60 , so that the front casing  51  and rear casing  53  are integrally engaged. 
   In addition, an engaging pin  80  is protruding from both rear lower portions of a rim portion of the front casing  51 . A receiving hole  90  ( FIG. 7 ) is formed at both front lower portions of the rear casing  53 . Therefore, since the engaging pin  80  is engaged into the receiving hole  90 , the lower portions of the front and rear casings,  51  and  53  respectively, are engaged. In addition, since the snap pin  100  is inserted into the receiving hole  90 , the front casing  51  is not easily disassembled from the rear casing  53 . 
   The snap portions and the engaging portions are explained in more detail with reference to  FIGS. 4 and 5A  through  5 C. As shown therein, the snap portion  60  is backwardly protruding from the lower surface of the upper rim portion  56  of the front casing  51 . The snap portion  60  is formed of a rectangular plate having a certain length and an elastic material. Three inner corner portions of the snap portion  60  are cut away, so that an elastic plate  62  having a proper elastic force is formed. In addition, a rectangular engaging hole  63  is formed at an intermediate portion of the elastic plate  62 . A slant surface  64  having a certain slant angle is formed at one end of the snap portion  60 . 
   In addition, the engaging portion  70  of the rear casing  53  is formed at a lower surface of the upper rim portion  57  of the rear casing  53  to correspond with the snap portion  60  of the front casing  51 . The engaging portion  70  has an engaging shoulder portion  73  at an intermediate portion of the same, and a pair of guides  74  are formed at both sides of the engaging shoulder portion  73 . 
   The front portion  71  of the engaging shoulder portion  73  is circular, and a vertical wall is formed at the rear surface portion  72 , so that the engaging shoulder portion  73  slides on the slant surface  64  and is engaged to the engaging hole  63 . 
   The length L 1  of each of the guides  74  is longer than the length L 2  of the engaging shoulder portion  73 . In addition, the distance D 1  between the guides  74  is larger than the length D 2  in the direction of the width of the snap portion  60 . Therefore, when the snap portion  60  is engaged to the engaging portion  70 , the end portions of the guides  74  contact first with the outer surface of the snap portion  60 , so that the engaging shoulder portion  73  is accurately engaged to the engaging hole  63  of the snap portion  60 . 
   As shown in  FIG. 5B , when the snap portion  60  and the engaging portion  70  are integrally engaged, a gap  58   a  is formed between the front and rear casings  51  and  53  respectively. A certain manual tool is inserted into the gap  58   a  when disassembling the front and rear casings,  51  and  53  respectively. When fabricating the snap portion  60  and the engaging portion  70 , the size of the gap  58   a  is determined. 
   The engaging structure of the lower portions of the front and rear casings is explained with reference to  FIGS. 6 and 7 . As shown therein, an engaging pin  80  is backwardly protruding from both rim portions  56  (on the left and right side) of the rear surface of the lower portion of the front casing  51 . The engaging pin  80  is formed of a rectangular bar having a certain size. A pair of reinforcing shoulder portions  81  are formed at the upper portion of the engaging pin  80 . An engaging portion (or detent)  82  is formed at a lower end portion of the engaging pin  80 . 
   A pair of the reinforcing shoulder portions  81  are protruded from both upper surface portions of the engaging pin  80  and have a certain height. The reinforcing shoulder portions  81  are distanced by a predetermined distance t 1 . 
   A receiving hole  90  of the rear casing  53  is formed at both sides of the front lower portion  54  of the rear casing  53 . The receiving hole  90  is rectangular and is extended backwardly by a certain distance and is accessible to the outside of the rear casing  53 . A pair of engaging shoulder portions  92  are formed at both sides of a bottom portion  91  of the receiving hole  90 . Since the engaging shoulder portions  92  have a slant surface, the rear portions of the engaging shoulder portions  92  are higher than the front portions of the same. Therefore, the engaging portion  82  of the engaging pin  80  of the front casing  51  slides backwardly along the slant surface  93  of the engaging shoulder portions  92  and is engaged with the engaging shoulder portions  92 . 
   An engaging groove  94  cut-away in a step shape is formed at the top portion  95  of the receiving hole  90 . A rectangular fixing hole  96  is formed through the top portion  95  of the receiving hole  90  at a certain distance from the engaging groove  94 . 
   When the engaging pin  80  is engaged to the engaging shoulder portions  92  of the receiving hole  90 , a user upwardly pushes the engaging pin  80 , so that it is possible to manually separate without using a certain tool such as a driver. While the user is using the monitor  50 , the lower portion of the casing may be opened. In order to prevent the above-described problem, a snap pin  100  is formed. 
   The snap pin is explained in more detail with reference to  FIGS. 7 ,  9  and  10 . As shown therein, a snap pin  100  includes an upper body  101 , a lower body  103  formed at a lower portion of the upper body  101 , and a connection portion  102  for integrally connecting the upper and lower bodies  101  and  103 . 
   The upper body  101  is formed of a polygonal plate and has a front portion integrally connected with the connection portion  102 , and a protrusion (or detent)  106  is downwardly formed at the bottom of the end portion of the upper body  101 . 
   The lower body  103  has a front end portion integrally connected with the connection portion  102 . The end portion of the lower body  103  is formed in a V-shape separated into first and second members  104  and  105  respectively. The first and second members  104  and  105  are formed of an elastic force material and may be transformed in the arrow direction  107  in the drawings. In addition, the protrusions (or detents)  104   a  and  105   a  are downwardly projecting from the lower surface of the end portions of the first member  104  and second member  105  respectively. The upper and lower bodies  101  and  103  are integrally connected by the connection portion  102  having a certain height, and a certain space is formed between the upper and lower bodies  101  and  103 . 
   In the case that the snap pin  100  is engaged into the receiving hole  90 , the top portion  95  of the receiving hole  90  is inserted into the space. In addition, a protrusion  106  of the upper body  101  slides on the upper surface of the top portion  95  of the receiving hole  90  and is engaged with the fixing hole  96 . Therefore, the snap pin  100  is engaged with the top portion  95  of the receiving hole  90 . 
   Referrring to  FIG. 10 , the width t 2  of the lower body  103  is smaller than the distance t 1  of the reinforcing shoulder portion  81  of the engaging pin  80 . The distance t 3  between the first member  104  and second member  105  is smaller than the distance t 1  when the first member  104  and second member  105  of the lower body  103  are deformed in the direction opposite to the arrow  107  and are received between the reinforcing shoulder portions  81  of the engaging pin  80 . On the other hand, in the case that the first and second members  104  and  105  are widened in the arrow direction  107 , the distance t 3  between the first and second members  104  and  105  is larger than the distance t 1  of the reinforcing shoulder portions  81 , so that the first and second members  104  and  105  are not received between the reinforcing shoulder portions  81 , namely, are positioned at the top of the reinforcing shoulder portion  81 . 
   Therefore, the snap pin  100  is positioned between the engaging pin  80  and the top portion  95  of the receiving hole  90 , so that it is possible to prevent the engaging pin  80  from escaping from the engaging shoulder portion  92  of the receiving hole  90 . The engaging operation of the monitor according to the present invention will be explained with reference to the accompanying drawings. As shown in  FIGS. 4 ,  5 A and  5 B, in the case that the rear casing  53  is engaged to the front casing  51  by a user, the engaging portion  70  of the rear casing  53  is aligned at the engaging position with respect to the snap portion  60  of the front casing  51 . In addition, the rear casing  53  is pushed in the arrow direction  66 , so that the snap portion  60  is positioned between the guides  74 . 
   When the inner surfaces  76  of the guides  74  contact with the outer surface  65  of the snap portion  60 , the guides  74  guide so that the engaging shoulder portion  73  is accurately fixed by the snap portion  60 . 
   When the engaging shoulder portion  73  contacts with the slant portion  64  of the snap portion  60 , the front surface of the engaging shoulder portion  73  slides along the slant surface  64 . At this time, the elastic plate  62  of the snap portion  60  downwardly moves. Therefore, the engaging shoulder portion  73  is inserted into the engaging hole  63  formed at the snap portion  60  beyond the slant surface  64 , so that the upper portions of the front and rear casings  51  and  53  are integrally engaged. 
   As shown in  FIGS. 4 ,  5 B and  5 C, the case that the rear casing  53  is separated from the front casing  51  will be explained. First, a certain tool such as a driver  58  is inserted into the gap  58   a  formed between the front casing  51  and the rear casing  53 . In addition, the driver  58  is pushed in the arrow direction  58   b , so that the end portion  58   c  of the driver  58  contacts with the upper surface of the elastic plate  62  and downwardly pushes the elastic plate  62 . In addition, the engaging plate  73  escapes from the engaging hole  63  of the elastic plate  62  by backwardly moving the rear casing  53 . Therefore, the engaging shoulder portion  73  slides along the slant surface  64  of the snap portion  60  and is separated from the snap portion  60 . As a result, the upper engaged portions of the front and rear casings  51  and  53  are separated from each other. 
   The upper engaging portions of a first side are separated, and the upper engaging portions of a second side are separated. Since the upper engaging structure of the second side is the same as the first side, the separation process is the same. 
   While the upper engaging portions of the second side are being separated, the separated upper engaging portions of the first side may be engaged again. In the upper engaging structure of the monitor  50 , however, the engaging shoulder portion  73  is backwardly pushed by the length of the slant surface  64  and is detached from the snap portion  60 . Therefore, it is possible to prevent a re-engagement at the upper engaging structure of one side. 
   The lower engagement of the monitor is explained with reference to  FIGS. 7 ,  9  and  10 . As shown therein, in the case that the user engages the rear casing  53  to the front casing  51 , the snap pin  100  is engaged into the receiving hole  90  of the rear casing  53 . Namely, the first member  104  and second member  105  of the snap pin  100  are aligned in the direction of the cut-away groove  96  formed at the top portion  95  of the receiving hole  90 , and the snap pin  100  is pushed by an external  11 , force. Therefore, the snap pin  100  is moved by an external force, and the protrusion  106  is backwardly moved along the upper surface of the top portion  95  of the receiving hole  90  and is engaged into the fixing hole  96 . 
   At this time, the top portion  95  of the receiving hole  90  is positioned in a certain space formed by the upper body  101  and lower body  103 . When the snap pin  100  is fixed in the receiving hole  90 , the first member  104  and second member  105  pass through the receiving hole  90  and are protruding to the outside of the receiving hole  90 . 
   At this time, the first member  104  and second member  105  are widened in the arrow direction  107 . In addition, since a certain distance is maintained between the lower body  103  of the snap pin  100  and the bottom portion  91  of the receiving hole  90 , the engaging pin  80  is inserted. 
   After the snap pin  100  is engaged into the receiving hole  90 , the user aligns the front casing  51  and the rear casing  53  at an engaging position. In addition, the front casing  51  is backwardly moved, so that the engaging pin  80  is inserted into the receiving hole  90  of the rear casing  53 . When the engaging pin  80  is inserted into the receiving hole  90 , the engaging portion  82  of the engaging pin  80  contacts with the upper surfaces  93  of the engaging shoulder portions  92  of the receiving hole  90 . 
   Therefore, the engaging portion  82  of the engaging pin  80  is engaged by the engaging shoulder portions  92 , so that the lower portions of the front casing  51  and the rear casing  53  are integrally engaged. At this time, since an end portion of the engaging pin  80  is exposed to the outside of the lower surface of the rear casing  53 , a user can disassemble using a certain tool such as a driver. 
   In the case that the lower portions of the front and rear casings  51  and  53  are separated, the user aligns the first member  104  and second member  105  of the snap pin  100  exposed to the outside of the lower surface of the rear casing  53  in the arrow direction  107 . At this time, since the width t 2  of the lower body  103  of the snap pin  100  is smaller than the distance t 1  of the reinforcing shoulder portion  81  of the engaging pin  80 , the snap pin  100  is received between the reinforcing shoulder portions  81 . Therefore, since a certain space by which the engaging pin  80  is upwardly moved is formed, the engaging pin  80  is upwardly moved by a certain distance. 
   After the engaging pin  80  is upwardly moved by a certain distance, the user upwardly pushes the lower portion of the engaging pin  80  in the arrow direction  59 , so that the engaging portion  82  of the engaging pin  80  is separated from the engaging shoulder portion  92  of the receiving hole  90 . After the engaging pin  80  is separated from the receiving hole  90 , the front casing  51  is forwardly moved by a certain distance, so that it is possible to separate the front casing  51  and the rear casing  53 . After one side of the monitor is separated, the engaging portions of the other side may be separated in the same manner. 
   As described above, in the casing upper engaging structure of the monitor according to the present invention, an assembling process is simple, and the assembling time is decreased. In addition, the slant surface of the end portion of the snap portion has a certain length, so that it is possible to prevent a re-engagement of the upper portion of the other side while the upper engaging structure is separated. In the monitor casing according to the present invention, a certain tool such as a driver is not used based on the lower engaging structure of the snap method. It is possible to assemble and disassemble based on a decreased process, so that the assembling and disassembling time are decreased. In order to prevent the casing lower engaging structure of the monitor from being easily separated by an external impact, the snap pin is used, so that it is possible to prevent the front and rear casing from being randomly separated. 
   Although the preferred embodiment 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.