Abstract:
A curvature examining jig for examining the curvature of a circuit board quickly and accurately includes a platform and a carrier. An examining region is defined on the platform so as for the circuit board to be disposed flatly within the examining region. A recess is disposed in the examining region and configured to receive a protrusion of the circuit board. The carrier is slidably coupled to the platform, configured to move along the margin of the circuit board, and provided with a plurality of plug gauges facing the platform closely and configured to move to the examining region along with the carrier. Accordingly, the curvature examining jig is convenient in holding a circuit board having a protrusion, quick and accurate in examining the curvature of the circuit board, and effective in enhancing the efficiency of production lines.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 099136152 filed in Taiwan, R.O.C. on Oct. 22, 2010, the entire contents of which are hereby incorporated by reference. 
     FIELD OF THE TECHNOLOGY 
     The present invention relates to curvature examining jigs, and more particularly, to a curvature examining jig for examining the curvature of a circuit board quickly and accurately. 
     BACKGROUND 
     Due to the ever-increasing demand for information, plenty of portable electronic products, such as notebook computers, panel computers, and e-book readers, were developed. In addition to their functionality, commercially available electronic products are expected, by electronic product consumers, to be lightweight, compact, and portable. To this end, electronic product manufacturers attach great importance to the flatness of a circuit board inside an electronic product they manufacture. The manufacturing process of a circuit board for use with an electronic product entails welding plenty of electronic components. Thus, during the manufacturing process, the circuit board is often heated up or cooled down by solder, and in consequence the circuit board is deformed, more or less. Sometimes, a circuit board bends greatly or ends up with dislocation of holes/apertures when bent to thereby prevent the circuit board from being installed inside a casing of an electronic product and reduce the yield of the production of the electronic product. As a result, it is necessary to examine the curvature of a circuit board before the circuit board is installed inside the casing of an electronic product, otherwise whatever subsequent operations performed during the manufacturing process will be destined to fail. 
     Referring to  FIG. 1 , there is shown a schematic view of examining the curvature of a circuit board  1  according to the prior art. As shown in the drawing, to examine the circuit board  1 , an examination worker puts the circuit board  1  on a platform  2  flatly, lifts a plug gauge  3  (0.4 mm thick approximately) manually in a manner that the plug gauge  3  faces the platform  2  closely, and eventually moves the plug gauge  3  along the margin of the platform  2  until the plug gauge  3  is positioned at a corner  11  of the circuit board  1 . Possibility of moving the plug gauge  3  from the corner  11  to between the circuit board  1  and the platform  2  indicates that the curvature of the circuit board  1  exceeds the allowable tolerance and thus is unfit for a subsequent assembly operation. Impossibility of moving the plug gauge  3  from the corner  11  to between the circuit board  1  and the platform  2  indicates that the curvature of the circuit board  1 , at the corner  11 , falls within the allowable tolerance. Afterward, other corners  12 ,  13 ,  14  are manually examined by the examination worker with the plug gauge  3 . A failure to move the corners  11 ,  12 ,  13 ,  14  to between the circuit board  1  and the platform  2  with the plug gauge  3  indicates that the curvature of the circuit board  1  in its entirety falls within the allowable tolerance and thus does not prevent any subsequent assembly operation from being carried out on the circuit board  1 . However, it is time-consuming and laborious to lift the plug gauge  3  manually in order to examine the corners  11 ,  12 ,  13 ,  14  of the circuit board  1  solely for the purpose of examining the curvature of the circuit board  1 . Also, examination is unlikely to be accurate when it is carried out by lifting the plug gauge  3  manually and examining the corners  11 ,  12 ,  13 ,  14  of the circuit board  1 , because, in so doing, the examination worker does not always make sure that the plug gauge  3  is facing the platform  2  flatly and closely. 
     Referring to  FIG. 2 , there is shown another schematic view of examining the curvature of the circuit board  1  according to the prior art. As shown in the drawing, a conventional process of examining the curvature of the circuit board  1  is inconvenient when a protrusion  17  of a relatively large size is disposed on the circuit board  1  by soldering. Examination of the curvature of the circuit board  1  is inaccurate, because the circuit board  1  lying on the platform  2  is tilted by the protrusion  17 . A remedial approach, though an inconvenient one, to improving the accuracy of examination entails putting the circuit board  1  on the platform  2  at a position thereof such that the protrusion  17  soldered to the circuit board  1  is outside of the platform  2  so as to make sure that the circuit board  1  lies flatly on the platform  2 . Afterward, the corner  11  of the circuit board  1  is examined with the plug gauge  3 . The inconveniency thus incurred repeats whenever the circuit board  1  has to be carefully positioned on the platform  2  in order for the protrusion  17  to lie outside the platform  2  before the commencement of the examination of the corners  12 ,  13 ,  14  of the circuit board  1 . 
     Accordingly, it is imperative to provide a jig for examining the curvature of a circuit board quickly and accurately. 
     SUMMARY 
     In view of the drawbacks of the prior art, it is an objective of the present invention to provide a curvature examining jig for examining the curvature of a circuit board quickly and accurately. 
     In order to achieve the above and other objectives, the present invention provides a curvature examining jig for examining the curvature of a circuit board with a protrusion. The curvature examining jig comprises a platform and a carrier. The platform is defined with an examining region so as for the circuit board to lie flatly within the examining region. The examining region has therein a recess for receiving the protrusion. The carrier is slidably coupled to the platform, configured to move along a margin of the circuit board, and provided with a plurality of plug gauges facing the platform closely and movable to the examining region together with the carrier. 
     Accordingly, the curvature examining jig of the present invention examines the curvature of a circuit board quickly and accurately. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A detailed description of further features and advantages of the present invention is given below so that a person skilled in the art can understand and implement the technical contents of the present invention and readily comprehend the objectives, features, and advantages thereof by reviewing the disclosure of the present specification and the appended claims in conjunction with the accompanying drawings, in which: 
         FIG. 1  (PRIOR ART) is a schematic view of examining the curvature of a circuit board according to the prior art; 
         FIG. 2  (PRIOR ART) is another schematic view of examining the curvature of the circuit board according to the prior art; 
         FIG. 3  is a perspective view of a curvature examining jig according to a first preferred embodiment of the present invention; 
         FIG. 4  is an exploded view of the curvature examining jig according to a second preferred embodiment of the present invention; and 
         FIG. 5  is a perspective view of the curvature examining jig according to the second preferred embodiment of the present invention when assembled. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 3 , there is shown a perspective view of a curvature examining jig according to a first preferred embodiment of the present invention. As shown in the drawing, the curvature examining jig of the present invention configured to examine the curvature of a circuit board  1  shown in  FIG. 1  comprises a platform  4 ′ and a carrier  52 . The platform  4 ′ is panel-shaped and defined with an examining region  420 ′ so as for the circuit board  1  to lie flatly within the examining region  420 ′. The examining region  420 ′ has substantially the same dimensions as the circuit board  1  does. A plurality of protrusions (not shown) protrude from beneath the circuit board  1 . Examples of the protrusions are electronic components. A recess  421 ′ for receiving the protrusions of the circuit board  1  is disposed in the examining region  420 ′ of the platform  4 ′. As a result, the circuit board  1  may lie flatly on the platform  4 ′. Under its own weight, the circuit board  1  is fixed to the platform  4 ′. The carrier  52  is slidably coupled to the platform  4 ′, configured to move along the margin of the circuit board  1 , and provided with a plurality of plug gauges  51 ′. The plug gauges  51 ′ face the platform  4 ′ closely and are movable to the examining region  420 ′ together with the carrier  52 . 
     The plug gauges  51 ′ each have a body  511 , an L-shaped leaf spring  512 ′, and a fixing plate  513 . The L-shaped leaf spring  512 ′ has two ends soldered to the fixing plate  513  and the body  511 , respectively. Among others, it is feasible for the body  511 , the L-shaped leaf spring  512 ′, and the fixing plate  513  to be integrally formed as a unitary unit, that is, the plug gauge  51 ′. The fixing plate  513  is engaged with and thus fixed to the carrier  52 . The body  511  faces the platform  4 ′ flatly and closely, and is movable to the examining region  420 ′ together with the carrier  52 . The body  511  is of a thickness of 0.4 mm approximately. Two of the plug gauges  51 ′ are positioned outside of a margin  15  of the circuit board  1 . The other two of the plug gauges  51 ′ are positioned outside of an opposing margin  16  of the circuit board  1 . The bodies  511  of the plug gauges  51 ′ are positioned proximate to four corners  11 ,  12 ,  13 ,  14  of the circuit board  1 , respectively. The carrier  52  lies flatly on the platform  4 ′ and is movable to and fro across the platform  4 ′; in other words, the carrier  52  is capable of reciprocation and lateral displacement relative to the platform  4 ′. Alternatively, it is the platform  4 ′ which is capable of reciprocation and lateral displacement relative to the carrier  52 . Each instance of the lateral displacement of the carrier  52  or the platform  4 ′ enables two said plug gauges  51 ′ positioned outside of the margin  15  or the margin  16  of the circuit board  1  to move toward the circuit board  1  laterally. If the bodies  511  are unable to move to between the circuit board  1  and the platform  4 ′, the bodies  511  will be stopped by the circuit board  1  and thus will deviate relative to the fixing plate  513 , and in consequence the L-shaped leaf spring  512 ′ will undergo deformation, thereby allowing an examination worker to quickly determine that the curvature of the circuit board  1  falls within the allowable tolerance. If one or two of the bodies  511  are able to move to between the circuit board  1  and the platform  4 ′, the plug gauges  51 ′ will not undergo deformation, thereby allowing the examination worker to quickly determine that the curvature of the circuit board  1  exceeds the allowable tolerance. 
       FIG. 4  is an exploded view of the curvature examining jig according to a second preferred embodiment of the present invention. Referring to  FIG. 3  and  FIG. 4 , in addition to the structure of the plug gauges  51 ′ in the first preferred embodiment, plug gauges  51  in the second preferred embodiment each have the body  511 , a connecting spring  512 , and the fixing plate  513 . The connecting spring  512  has two ends soldered to the fixing plate  513  and the body  511 , respectively. The fixing plate  513  is engaged with and thus fixed to carrier  52 . The body  511  is of a thickness of 0.4 mm approximately. The body  511  flatly and closely faces the platform  4 ′ of the first preferred embodiment and is movable to the examining region  420 ′ together with the carrier  52 . 
     The carrier  52  is a rectangular frame defined with a receiving region  521  for receiving the circuit board  1 . The plug gauges  51 ,  51 ′ are each fixed to the wall of the receiving region  521  of the carrier  52 . The carrier  52  is made of an antistatic material, such as bakelite. Making the carrier  52  look like a rectangular frame allows the examination worker to scrutinize the inside of the receiving region  521  of the carrier  52  with the naked eye and thereby facilitates the examination work.  FIG. 5  is a perspective view of the curvature examining jig according to the second preferred embodiment of the present invention when assembled. Referring to  FIG. 4  and  FIG. 5 , a platform  4  comprises a carrying member  41  and a replacing member  42 . The carrying member  41  is made of an antistatic material, such as bakelite. The examining region  420  and a recess  421  are disposed at the replacing member  42  for receiving a protrusion  17 , such as an electronic component, beneath the circuit board  1 . The replacing member  42  is disposed on the carrying member  41  so as for the circuit board  1  to lie flatly on the replacing member  42 . The replacing member  42  and the carrying member  41  are coupled together by “posts and holes”, magnets, or mechanical fastener bodies such as Velcro® surfaces or straps. The bodies  511  of the plug gauges  51  face the replacing member  42  flatly and closely. The replacing member  42  is made of a mirror-finished material conducive to reduction in the friction between the replacing member  42  and the bodies  511 . The replacing member  42  is replaceable according to the specifications of the circuit board  1 , and thus a curvature examining jig of the present invention is capable of examining the circuit board  1  of different specifications. 
     The recesses  421 ′,  421  each have at least a receiving chamber for receiving all the electronic products beneath the circuit board  1 . The margin of the circuit board  1  rests upon the platform  4 ′ or the replacing member  42 . In an embodiment of the present invention, the recesses  421 ′,  421  each comprise a plurality of receiving chambers for receiving electronic components beneath the circuit board  1 , respectively, whereas the platform  4 ′ or the replacing member  42  underpins the circuit board  1  except for the electronic component thereunder. 
     A plurality of rails  43  are disposed on the platform  4 . The rails  43  are adhered to or fastened to the platform  4 , and are positioned outside of the replacing member  42 . A plurality of rollers  53  are pivotally coupled to the carrier  52 , and are positioned on two outer sides of the carrier  52 . The rollers  53  are configured to roll along the rails  43 , respectively, so as for the carrier  52  to move along the margin of the circuit board  1  and move to and fro across the platform  4 . Alternatively, the platform  4  may move to and fro relative to the carrier  52 . In addition, both the rails  43  and the rollers  53  in the second preferred embodiment are also applicable to the first preferred embodiment. 
     A stopping block  431  is disposed at each of the two ends of each of the rails  43  for stopping a corresponding one of the rollers  53  and thereby limiting the range of movement of the carrier  52 . The purpose of the stopping blocks  431  is to prevent the rollers  53  from running off the rails  43  and thus prevent the carrier  52  from being thrown off or damaged. The stopping blocks  431  are each adhered to or fastened to a corresponding one of the rails  43 , or are each formed integrally with the corresponding one of the rails  43 . 
     The platforms  4  (the replacing member  42 ) and the platform  4 ′ are made of a mirror-finished material such that the platforms  4  (the replacing member  42 ) and the platform  4 ′ have a smooth surface for reducing the friction between each of the bodies  511  and the platform  4  (the replacing member  42 ) and the platform  4 ′, thereby allowing the bodies  511  to move across the platform  4  (the replacing member  42 ) and the platform  4 ′ while facing the platform  4  (the replacing member  42 ) and the platform  4 ′ flatly and closely. 
     Referring to  FIGS. 4 and 5 , in the second preferred embodiment of the present invention, it is desirable that the circuit board  1  can lie flatly on the replacing member  42 . Under its own weight, the circuit board  1  is fixed to the replacing member  42 . The protrusion  17 , such as an electronic component, protruding from beneath the circuit board  1  is received in the recess  421  of the replacing member  42  to enable the circuit board  1  to lie flatly on the replacing member  42 . Before examining the circuit board  1 , the examination worker puts four said plug gauges  51  inside the carrier  52 . Two of the plug gauges  51  are disposed outside of the margin  15  of the circuit board  1 . The other two of the plug gauges  51  are disposed outside of the opposing margin  16  of the circuit board  1 . The bodies  511  of the plug gauges  51  face the replacing member  42  flatly and closely. Before examining the circuit board  1 , the examination worker moves the carrier  52  horizontally so as for two said plug gauges  51  positioned outside of the margin  15  of the circuit board  1  to move horizontally toward the corners  11 ,  12  of the circuit board  1 . Movement of either or both of two said bodies  511  to between the circuit board  1  and the replacing member  42  is a sign that the width of the gap between the replacing member  42  and the corner  11  or  12  of the circuit board  1  is larger than 0.4 mm, and thus the examination worker is able to determine quickly that the curvature of the circuit board  1  exceeds the allowable tolerance. A failure to move two other said bodies  511  to between the circuit board  1  and the replacing member  42  (in this failure scenario, two said bodies  511  actually deviate from their expected course) is a sign that the examination worker can swiftly determine that the curvature of the circuit board  1 , at the corners  11 ,  12 , falls within the allowable tolerance. Likewise, it is feasible for the examination worker to move carrier  52  horizontally but in the opposite direction so as for two said plug gauges  51  positioned outside of the opposing margin  16  of the circuit board  1  to move horizontally toward the corners  13 ,  14  of the circuit board  1 . Movement of either or both of two said bodies  511  to between the circuit board  1  and the replacing member  42  is a sign that the width of the gap between the replacing member  42  and the corner  13  or  14  of the circuit board  1  is larger than 0.4 mm, and thus the examination worker is able to determine quickly that the curvature of the circuit board  1  exceeds the allowable tolerance. A failure to move two other said bodies  511  to between the circuit board  1  and the replacing member  42  (in this failure scenario, two said bodies  511  actually deviate from their expected course) is a sign that the examination worker can swiftly determine that the curvature of the circuit board  1 , at the corners  13 ,  14 , falls within the allowable tolerance, and if the examination worker also determines that the curvature of the circuit board  1 , at the corners  11 ,  12 , falls within the allowable tolerance, the examination worker can go further to determine that the curvature of the circuit board  1  in its entirely falls within the allowable tolerance. 
     The foregoing embodiments are provided to illustrate and disclose the technical features of the present invention so as to enable persons skilled in the art to understand the disclosure of the present invention and implement the present invention accordingly, and are not intended to be restrictive of the scope of the present invention. Hence, all equivalent modifications and variations made to the foregoing embodiments without departing from the spirit and principles in the disclosure of the present invention should fall within the scope of the present invention as set forth in the appended claims.