Abstract:
A system for inspecting indicia on a golf ball is disclosed herein. The system uses a multitude of cameras to analyze indicia that has been printed on the surface of the golf ball in order to accept or reject each golf ball. In a preferred embodiment, the system is placed in-line with the printing of the indicia on the golf ball surface, and prior to the curing of the indicia in order to easily remove unacceptable indicia.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a visual verification system. More specifically, the present invention relates to a visual verification system for golf ball indicia. 
     2. Description of the Related Art 
     Golf balls have indicia such as logos, brand names and the like to identify the golf ball and its source of origin. The indicia are typically printed on a base-coated surface of the cover of the golf ball, and covered with a top-coating to prevent damage during impact with a golf club. Thus, the indicia must have a perfect appearance since it is often the most distinctive quality of a golf ball. 
     The current inspection process is visual inspection of the indicia subsequent to top-coating. Thus, it is not until the golf ball is ready for packaging that the indicia is inspected for appearance and quality. 
     Automated vision inspection systems have been utilized in many industries to increase production times. Typically, a predetermined digital image is compared to the product to be inspected by the vision system. The vision system will look for differences in contrast, brightness, proportions, discontinuations, and the like. When a variance is discovered, the system will reject the inspected product. Although such systems have found acceptance in various industries, the golf ball industry has failed to develop such a vision inspection system due to unique problems associated with the golf ball industry. 
     First, current indicia printing systems employed in the golf ball industry do not have sufficient space to enable any type of vision inspection system. Second, most indicia printing systems in the golf ball industry employ inks that necessitate curing prior to vision inspection and thus inspection is rendered partially ineffective since the only possibility is to reject the golf ball. Thirdly, a golf ball is a dimpled spherical unit that has indicia printed on several areas of the sphere. A vision inspection system must be able to rotate the golf ball to provide inspection of all of the golf ball&#39;s indicia, and the system must be able to compare the correct areas to those being inspected to prevent rejection of good golf balls. Fourthly, the vision inspection system must not ruin the indicia through its inspection of the indicia, or rotation of the golf ball to inspect the indicia. Fifthly, the system must be capable of inspecting at a speed that does not interrupt the production cycle. The inspection system should not be the production time determinate. Those skilled in the art also recognize the many other problems associated with vision inspection of golf ball indicia. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is a system designed for vision inspection of golf ball indicia that provides a solution to all of the unique problems associated with vision inspection of golf ball indicia. The present invention allows for non-altering vision inspection of all of the golf ball&#39;s indicia without reducing production time. The present invention also provides a mechanism for in-line rejection of defective indicia golf balls to remove and re-print the indicia. 
     One aspect of the present invention is a method for inspecting golf ball indicia. The general method commences with transferring a golf ball to a vision inspection station. The golf ball has indicia printed thereon. Next, the golf ball is maneuvered to position the indicia within viewing of a first camera within the vision inspection system. Next, the indicia is scanned and an image of the indicia is transferred to a computer for inspection of the indicia. Then, the image is analyzed to determine if the indicia is within acceptable parameters. 
     Another aspect of the present invention is a method for in-line inspection of golf ball indicia. The method begins with transferring a golf ball to a printing station, and printing a first indicia on the golf ball. Then, the golf ball is rotated and a second indicia is printed on the golf ball. Next, the golf ball, with the first and second indicia thereon, is transferred to a first camera station of a vision inspection device. Next, the golf ball is oriented to position the first indicia in the view of a first camera, and an image of the first indicia is captured by the first camera and analyzed by the computer imaging program. Next, the golf ball, with the first and second indicia thereon, is transferred to a second camera station of the vision inspection device. Then, the golf ball is oriented to position the second indicia in the view of a second camera, and an image of the second indicia captured by the second camera and analyzed by the computer imaging program. Next, the golf ball, with the first and second indicia thereon, is transferred to a curing station if the analysis of the images of the first and second indicia are within acceptable parameters. 
     Another aspect of the present invention is a system for printing and inspection of an indicia on a golf ball. The system includes a conveyance line, a printing station, a vision inspection station and a curing station. At the printing station, a first indicia and a second indicia is printed on each of the plurality of golf balls. The printing station is disposed on the conveyance line. The vision inspection station is disposed on the conveyance line subsequent to the printing station. The vision inspection station includes a plurality of cameras disposed in relation to the conveyance line for capturing an image of the indicia on the golf ball for analysis. The system also includes a means for determining acceptable indicia and unacceptable indicia. Finally, the curing station is disposed subsequent to the vision inspection station. 
     Having briefly described the present invention, the above and further objects, features and advantages thereof will be recognized by those skilled in the pertinent art from the following detailed description of the invention when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is a side view of a printing system that utilizes the vision inspection system of the present invention. 
     FIG. 2 is a top plan view of FIG.  1 . 
     FIG. 3 is an isolated front view of the printing system of FIG. 1 
     FIG. 4 is an unprinted golf ball. 
     FIG. 5 is a golf ball with a first indicia printed thereon. 
     FIG. 6 is a golf ball with a first indicia and second indicia printed thereon. 
     FIG. 7 is a golf ball with a first indicia, second indicia and third indicia printed thereon. 
     FIG. 8 is an isolated top view of a golf ball holder utilized with the present invention. 
     FIG. 9 is an isolated top view of a golf ball holder with a gear bar disposed above. 
     FIG. 10 is a side view of a series of golf ball holders. 
     FIG. 11 is an isolated side view of the interior wall of a golf ball holder. 
     FIG. 12 is an isolated front view of the vision inspection station. 
     FIG. 13 is an isolated side view of the vision inspection station. 
     FIG. 14 is a view of the image of an indicia captured by the vision inspection station. 
     FIG. 15 is a view of the image of a second indicia captured by the vision inspection station. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIG. 1, an indicia printing system is generally designated  20 . The indicia printing system  20  is constructed to mark an identifying indicia or logo on a golf ball. More likely than not, one of the indicia or logos will indicate a company name and/or a well-known brand name. Thus, it is important that the indicia is printed perfect or near perfect since the appearance of the indicia will be associated with quality of golf ball, and logically the quality of the company that produces the golf ball. 
     The system generally includes a golf ball source  22 , a conveyor line  24 , a printing station  26 , a curing station  28 , and in-line vision inspection station  30  of the present invention. The in-line vision inspection station  30  is positioned between the printing station  26  and the curing station  28 . The conveyor line  24  transfers golf balls  32  from the golf ball source to the printing station  26  for indicia printing, then the conveyor line  24  transfers the golf balls  32  to the vision inspection station  30 . At the vision inspection station  30 , the quality of the indicia is determined for each golf ball  32 , and each indicia. If the indicia printed on the golf balls  32  are acceptable, then the conveyor line  24  transfers the golf balls  32  to the curing station  28 . Unacceptable golf balls  32  are transferred to an indicia removal station  34  for removal of the unacceptable indicia. 
     Each golf ball  32  is transferred from the source  22 , which is typically a hopper, to a golf ball holder  38 . The source  22  accumulates the golf balls  32  subsequent to the painting of the golf balls  32  with a base coat or clear coat. Alternatively, the source  22  accumulates golf balls  32  subsequent to molding a doped cover material (doped with a whitening agent such as titanium dioxide). 
     The conveyor line  24  is composed of a plurality of golf ball holders  38  that are interconnected to form a chain-like mechanism on the conveyor line  24 . Two adjacent golf ball holders  38  are positioned on a plate  56  which is connected to other plates  56  by connectors  58  to form a chain of plates  56 . The chain of plates  56  also forms two parallel lines of golf ball holders  38 . As shown in FIGS. 8-11, each golf ball holder  38  is composed of a U-shaped frame body  40 . The U-shaped frame body has two upward extending arms  42   a  and  42   b . On the interior surface of each of the arms  42   a-b  is an engagement member  44   a-b . Each pair of engagement members  44   a-b  secure a golf ball  32  within the holder  38 . The engagement members  44   a-b  rotate the golf ball  32  about a imaginary central axis  60  through the golf ball  32 . 
     The fixed and controlled rotation of the golf ball  32  allows for indicia printing at several different locations on the surface  48  of the golf ball  32  as the golf ball  32  is conveyed from a first ink transfer pad  36   a  to a second ink transfer pad  36   b  to a third ink transfer pad  36   c . As shown in FIGS. 4-7, each time that the golf ball  32  is conveyed to an ink transfer pad  36 , the golf ball  32  is rotated for printing on an unprinted portion of the surface  48  of the golf ball  32 . The rotation is controlled and repeatable in order to inspect the indicia printing at the vision inspection station  30 . The rotation preferably ranges from 10 degrees to 320 degrees, more preferably from 45 degrees to 270 degrees, and most preferably from 90 degrees to 180 degrees. Each golf ball  32  is held within a holder  38  throughout the indicia printing and the vision inspection of the golf ball  32 . 
     FIG. 4 illustrates an unprinted golf ball  32 . The golf ball  32  may be a two-piece or multiple-piece golf ball, with a painted cover, or an unpainted cover such as an ionomer cover doped with titanium dioxide for coloring. The cover of the golf ball  32  is typically white, however, other colors may be used in practicing the present invention. FIG. 5 illustrates a first indicia  50  that has been printed of the surface  48  of the golf ball  32 . At FIG. 6, the golf ball  32  is rotated ninety degrees about the central axis  60  and a second indicia  52  is printed on the golf ball  32 . The first indicia  50  is still visible. At FIG. 7, the golf ball  32  is rotated another ninety degrees about the central axis  60  and a third indicia  54  is printed on the golf ball  32 . The second indicia  52  is still slightly visible. 
     A preferred printing station  26  is a transfer pad printing station in which transfer pads  36  transfer an ink image of an indicia to the golf ball  32 . Such a transfer pad printer is available from TransTech Company of Carol Stream, Ill. under the brand name SIRUIS  130 . A most preferred printing station  26  is one that uses an ultraviolet (“UV”) curable ink for transferring the ink image of an indicia to the golf ball  32 . A preferred ink is an UV curable ink sold under the trade name UVAB and available from Trans Tech of Carol Stream, Ill. The ink includes an UV curable resin, a coloring agent, a pigment/dye and a photoinitiator. Another UV curable ink is sold under the trade name PRISMFLEX and is available from Sun Chemical. However, those skilled in the pertinent art will recognize other conventional printing means could be used without departing from the scope and spirit of the vision inspection system of the present invention. One alternative would be to use a transfer pad printing with an alternative ink such as a single component ink. 
     Returning to FIGS. 8 and 9, each pair of adjacent golf ball holders  38  on a single plate  56  are positioned opposite to each other. A connection wall  61  of each golf ball holder  38  is attached to an adjacent connection wall  61  of the adjacent golf ball holder  38  by a common transition wheel  62 . Each transition wheel  62  lies under a cam bar  64  that has a plurality of cam pins  65  projecting downward therefrom. The cam pins  65  engage the transition wheel  62  during the conveyance of the golf ball holders  32  through the printing station  26  and through the vision inspection station  30 . The transition wheel  62  is rotated ninety degrees by the cam pin  65  thereby rotating the engagement member  44   b , and eventually the golf ball  32 . 
     In the vision inspection station  30 , a plurality cameras  70  are mounted above the lines of conveyance  24 . In a preferred vision inspection station  30  there are four cameras  70  mounted above each line of conveyance to capture each indicia that has been printed on the golf ball  32 . A fiber optic lighting device  68  provides the necessary lighting for imaging of the indicia  50  below the camera. The plurality of cameras  70  are preferably all CCD cameras. 
     As shown in FIG. 13, four cameras  70   a ,  70   c ,  70   e ,  70   g  are mounted above the line of conveyance  24 . Each golf ball holder  38  pauses for a predetermined period of time underneath a first camera  70   a  in order for an image of the indicia  50  to be captured as shown in FIG. 14, and then analyzed by a computer software program. Such a computer software program is available from Systech Solutions, Inc. of Cranbury, N.J. The rate of conveyance may preferably vary from 50-100 golf balls per minute. As the golf ball holder moves to the next camera  70   c , it is rotated ninety degrees by the cam pin  65  transition wheel  62  mechanism, or some similar mechanism. An image as shown in FIG. 15 of the second indicia  52  is captured and analyzed by a computer software program. This process continues for the other indicia at the other camera substations. 
     The computer imaging program looks at different image boxes  72 - 82  to determine if the indicia  50  meets a predetermined standard for such an indicia. The indicia  50  may preferably range in height from 0.05 inch to 0.20 inch, and may preferably vary in length from 0.10 inch to 1.04 inches. The color of each indicia  50 ,  52  and  54  may be any visible or detectable color, and the indicia  50  may be composed of different colors. The computer imaging program also analyzes the pixel content, the positioning of the text and characters of the indicia  50 , the intensity, and other like properties. More specifically, the vision inspection system detects flaws as minimal as 0.001 inch square on an image box  72 - 82  of 10 inch square. The flaws include detection of an absence of ink in an image box  72 - 82  where ink should be present, or the detection of the presence of ink in an image box  72 - 82  where ink should not be present. The vision inspection system also detects flaws in the structure of the cover of the golf ball  32 , and flaws in the paint on the golf ball  32 . The vision inspection system is also capable of having each camera  70  track the location of he indicia  50  on the golf ball up to a variance of five degrees. 
     If the golf ball  32  is acceptable, the golf ball  32  is transferred from the primary conveyor line  24  to a curing station conveyor line  46 . If the golf ball  32  is unacceptable, the golf ball  32  is transferred to the indicia removal station  34 , not shown. The curing station conveyor line  46  transfers the golf ball  32  to a curing station  28 . Preferably the ink for the first, second and third indicia  50 ,  52  and  54  is an ultraviolet curable ink, and the curing station  28  is a ultraviolet energy curing station having an ultraviolet light lamp disposed above the curing station conveyor line  46  to cure each of the first, second and third indicia  50 ,  52  and  54 . However, those skilled in the pertinent art will recognize that other inks and corresponding curing stations may be used without departing from the scope and spirit of the present invention. 
     From the foregoing it is believed that those skilled in the pertinent art will recognize the meritorious advancement of this invention and will readily understand that while the present invention has been described in association with a preferred embodiment thereof, and other embodiments illustrated in the accompanying drawings, numerous changes, modifications and substitutions of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing except as may appear in the following appended claims. Therefore, the embodiments of the invention in which an exclusive property or privilege is claimed are defined in the following appended claims.