Abstract:
A measuring system ( 100 ) for flatness degree measurement includes a measuring instrument ( 10 ) and a processing device ( 20 ). The measuring instrument has a base ( 12 ), a guide column ( 14 ), a sliding member ( 16 ), a digital micrometer ( 18 ) and a holding member ( 19 ). The guide column is vertically attached to the base. The sliding member is moveably attached to the guide column. The digital micrometer is firmly fastened to the sliding member. The holding member is configured for fixing a workpiece ( 40 ) and has a reference-standard surface formed thereon. The processing device electronically connects with the digital micrometer. The processing device receives a plurality of measured values from the digital micrometer and displays a testing result after processing the measured values.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to measuring systems and, particularly, to a measuring system with a digital micrometer and a method using the same. 
   2. Description of Related Art 
   In industrial production, it is often necessary to do a flatness degree measurement for a workpiece so as to ensure the dimension precision of the products. Manufacturers generally use a single micrometer or a three-dimensional measuring apparatus to measure the degree of flatness of the workpieces. 
   Although micrometers are light and handy, when a surveyor/inspector uses a single micrometer to measure the workpieces, the surveyor usually needs to read and record the parameters by hand, which make the measuring process time consuming. Also, man-made errors can easily be made when reading such measurements. In addition, the surveyor needs to determine whether the dimension of the workpiece is acceptable or not. As such, not only the work burden of the surveyor is increased, it also increases the time needed for the measuring process. 
   The three-dimensional measuring apparatus is generally large and complex, so that it tends to be hard to move. Therefore, the three-dimensional testing apparatus is suitable for placement in a laboratory to measure small quantities of samples, but it is not generally suitable for measuring products in large-scale production. 
   Therefore, a new measuring system is desired in order to overcome the above-described problems. 
   SUMMARY OF THE INVENTION 
   In one embodiment thereof, a measuring system for flatness degree measurement includes a measuring instrument and a processing device. The measuring instrument has a base, a guide column, a sliding member, a digital micrometer and a holding member. The guide column is vertically attached to the base. The sliding member is moveably attached to the guide column. The digital micrometer is firmly fastened to the sliding member. The holding member is configured for fixing a workpiece and has a reference-standard surface formed thereon. The processing device electronically connects with the digital micrometer. The processing device receives a plurality of measured values from the digital micrometer and displays a testing result after processing the measured values. 
   Other advantages and novel features will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Many aspects of the measuring system can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present measuring system. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
       FIG. 1  is an assembled, isometric view of a measuring system, in accordance with a present embodiment; 
       FIG. 2  is an isometric view of the measuring instrument shown in  FIG. 1 ; and 
       FIG. 3  is a flow chart of a processing device shown in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to  FIG. 1 , the measuring system  100  includes a measuring instrument  10  and a processing device  20  connected/linked with the measuring instrument  10 , in accordance with a present embodiment. 
   The measuring instrument  10  includes a base  12 , a guide column  14 , a sliding member  16 , a digital micrometer  18  and a holding member  19 . 
   Referring to  FIG. 2 , the base  12  is a rectangular flat board. The base  12  has an essentially flat upper surface  122 , so that the holding member  19  may be flatly arranged on the upper surface  122 , so as to reduce errors in measuring. The base  12  may, advantageously, be made of a metal with high density, such as stainless steel or the like, so that the weight and linear dimensions of the base  12  together are enough to keep the measuring instrument  10  balanced (i.e., the base  12  beneficially acts as a ballast for the measuring instrument  10 ). A fixing hole  124  is defined adjacent to an edge portion of the base  12 . 
   The guide column  14  may, advantageously, be made of a durable, rigid material, such as stainless steel, copper alloy, or the like, so the shape of the guide column  14  may stay the same even after repeated usage. The guide column  14  has a smooth circumference surface  142  and is configured (i.e., structured and arranged) for allowing the sliding member  16  to be easily moved along the guide column  14 . The guide column  14  is configured for engaging in the fixing hole  124  of the base  12 . 
   The sliding member  16  is approximately a rectangular block, and has a guide hole  164  and a receiving hole  166  respectively defined at two ends thereof. The guide hole  164  has an approximately similar diameter to the guide column  14 , for facilitating a slide fit therebetween. A bore (not shown) is defined in a sidewall of the sliding member  16  and is perpendicular to an axis of the guide hole  164 . A slot/aperture  169  is defined across the sliding member  16  so as to form two portions beside the slot/aperture  169 . The slot/aperture  169  enables the guide hole  164  to communicate with the surrounding environment. The width of the slot/aperture  169  is large enough that the two portions beside the slot/aperture  169  are moveable relative to the slot/aperture  169 . The bore is divided into two parts portion by the aperture  169 . An adjusting screw  168  is rotated into the bore to fastens the two opposite side portions of the slot/aperture  169 . Therefore, the diameter of the guide hole  164  can be expanded or reduced by rotating the adjusting screw  168 . 
   The digital micrometer  18  includes a main body  182 , a sleeve  184  and a measuring shaft  185 . The sleeve  184  is received in the receiving hole  166  of the sliding member  16  and is mounted on the main body  182  (e.g., the sleeve  184  is soldered/welded on the main body  182 ). The measuring shaft  185  has a contacting portion  186  at one end thereof. The measuring shaft  185  passes the sleeve  184  and extends through the main body  182 , with the contacting portion  186  extending out from the sleeve  184 . A cap  183  is mounted on another end of the measuring shaft  185  for lifting the measuring shaft  185 . A dial plate  187 , a zero reset button  1822  and a power button  1824  are set on the main body  182 . The zero reset button  1822  and the power button  1824  are located under the dial plate  187 . The dial plate  187  may display a movement distance of the contacting portion  186  of the measuring shaft  185  via pressing the zero reset button  1822 . That is, the zero reset button  1822  is configured for selectably establishing a zero reference level or datum plane, to provide a basis for measurement. An output interface  188  is formed in a shell of the main body  182 . The output interface  188  is used for transmitting dimensions data to the processing device  21 . 
   The holding member  19  has a flat bottom surface (not labeled), so that the holding member  19  can be flatly arranged on the base  12 . The holding member  19  is configured for fixing a workpiece  40 . A reference-standard surface (not shown) is formed on the holding member  19 , which is at a same horizontal level with an upper surface of a standard workpiece  40  fixed on the holding member  19 . A cover  30  is fixed on the holding member  19  across/over the workpiece  40 . The cover  30  has a top wall  32  and two sidewalls  34  vertically connecting with the two ends of the top wall  32 . The two sidewalls  34  respectively engage in two gaps  192  defined in the holding member  19 . A plurality of positioning holes  322  are defined across the top wall  32 , configured for receiving the measuring shaft  185 . The position of the positioning holes  322  is designed according to the shape of the workpiece  40  and, particularly, to one of the positioning holes  322  positioned above the reference-standard surface. 
   The processing device  20 , which advantageously is a programmable logic controller (PLC) or a computer, is used to process the data from the measuring instrument  10  and show/display a testing result. The processing device  20  includes, at least, a processor  21  and a display  29 . The processor  21  has an input module  22 , a storing module  24 , a processing module  26 , and a video-conversion module  28 . The input module  22  connects with the output interface  188  of the digital micrometer  18  is set to receive data (e.g., measured values) from the digital micrometer  18  via an electronic connection such as a data wire or a wireless link. The storing module  24  stores reference data and testing values transmitted from the digital micrometer  18  via the input module  22 . The reference data is, for example, a series of numbers in a range (e.g., 0.1 mm). The processing module  26  is configured for receiving the data transmitted from the input module  22  and for processing and comparing it with the reference data, so as to generate a result. The video-conversion module  28  is used to receive the signal of the test result and transform it into a video signal. The video-conversion module  28  electronically connects (e.g., hard-wire or wireless link) with the display  29 , so that the result might be display via the display  29 . It is to be further understood that the processing module  26  could be linked to a printer (not shown), as well. Either way, the display  29  and/or the printer would serve as data output modules. 
   In use, firstly, an user inputs a reference range value of a height of a normal workpiece  40 . The reference data is stored in the storing module  24 . The workpiece  40  is fixed on the holding member  19 , with the cover  30  mounted on the holding member  19  and over/across the workpiece  40 . The holding member  19  with the workpiece  40  and the cover  30  thereon is then placed on the base  12 . 
   The adjusting screw  168  is then rotated outwardly and the sliding member  16  moves downward. The user moves the holding member  19  so as to let the positioning hole  322  above the reference-standard surface correspond to the measuring shaft  185 . When the contacting portion  186  of the measuring shaft  185  touches the reference-standard surface via the corresponding positioning hole  322 , the sliding member  16  is tightened up by the adjusting screw  183 . The power button  1824  and the zero reset button  1822  are pressed down in order written, and the dial plate  187  shows “0”. The height of the reference-standard surface  192  is set to zero. 
   After that, the user lift up the measuring shaft  185  via the cap  183  while move the holding member  19  at the same time. When the measuring shaft  184  corresponds to another positioning hole  322  of the cover  30 , the measuring shaft  184  is slowly released. The contacting portion  186  of the measuring shaft  185  touches the upper surface of the workpiece  40 . The dial plate  184  shows/indicates the distance between the end of the contacting portion  186  and the reference-standard surface. When the point is lower/shorter than the reference-standard surface, the number/value is positive. Otherwise, when the end of the contacting portion  186  is higher/taller than the reference-standard surface, the number is negative. The signal corresponding to the number/value is transmitted to the input module  22  of the processor  21  via a data wire. The number/value is then restored in the storing module  24 . Then repeat the steps above so as to test the other points of the upper surface of the workpiece  40  via the positioning holes  322 . The numbers/values relative to the positioning points are then restored in the storing module  24 . 
   The processing module  26  processes the numbers/values relative to the testing points of the upper surface of the workpiece  40  and generate a result. If the result is in the reference range, the display  201  will show “pass”, indicating that the workpiece  40  is suitably dimensioned. Otherwise, if the result is out of the reference range, the display  201  will show “reject”, which means the workpiece  40  has one or more dimensions that are not in the acceptable range. 
   It should be understood that the cover  30  on the holding member  19  may be omitted, and the holding member  19  may be directly moved without lifting the measuring shaft  185 . 
   It is to be further understood that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.