Abstract:
A device ( 80 ) for reading a coded golf ball ( 40 ) comprises a helical track ( 82 ) on the inside or outside of a cylindrical housing ( 81 ), the track serving to change the orientation of the ball relative to an antenna coil ( 85 ) to ensure that the code is read. The track may be arranged horizontally and rotated by a motor; a flap ( 30 ) may be provided to avoid balls following each other too closely onto the helical track. Alternatively the track may be arranged vertically and the balls may fall under gravity.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to the identification of spherical objects and in particular to the identification of coded golf balls in a golf game or a golf driving range as disclosed in WO 99/48046. 
   2. Description of the Related Art 
   A problem in detecting a spherical object (such as a golf ball) when it is stationary or moving in a straight line, is that the orientation of a transponder within the object may be such that it is not detected by a sensing antenna. Moreover, in automated golf driving ranges as disclosed in WO 99/48046, stopping a ball for code-reading purposes introduces unnecessary delay. 
   BRIEF SUMMARY OF THE INVENTION 
   Accordingly the present invention seeks to provide an arrangement for reading a coded object while it is moving. 
   When moving golf balls around an automated golf driving range, they can accumulate upstream of reading devices. This can cause jamming. In addition, certain code-reading technologies are incapable of discriminating between two balls if they are too close. 
   Accordingly the present invention also seeks to overcome or reduce this problem. 
   In accordance with a first aspect of the present invention, there is provided a device for recording the code of a coded spherical object as it is moving comprising a sensing member and a path for conveying objects through or past the member, the means defining the path including a helical track along which the objects are constrained to move. 
   As the objects move along the track they rotate about different axes in space, so that, whatever their initial orientation, their code can be read by the sensing member, i.e. there can be no blind spots undetected by the sensing member. 
   As the objects move along the track they rotate about different axes in space, so that, whatever their initial orientation, their code can be read by the sensing member, i.e. there can be no blind spots undetected by the sensing member. 
   The code is preferably stored in an r.f. identification tag contained within a golf ball. The balls may be as disclosed in PCT/GB00/02461. In this case the sensing member is an antenna, which may have coils passing around and/or along the helical track. 
   The helical track is preferably arranged on the inside surface of a hollow cylindrical or frusto-conical member. 
   The helical track may be part of a driven member operated by an electric motor. The driven member may extend horizontally, in which case the inlet of the helical track can be configured to admit only one ball at a time. Means, such as a leaf spring, can be provided to engage inserted balls such that a following ball cannot enter the track immediately after an initial ball, nor can the following ball cause jamming. 
   Alternatively the axis of the helical track may be arranged vertically in which case the balls can move under the effect of gravity. This arrangement is particular suitable for coding technologies which can operate even with touching balls. Of course, a ball separation device may be provided upstream of the helical track if required. 
   According to a second aspect of the present invention, there is provided a method of ensuring that the code of a coded spherical object can be read by a sensing member comprising moving the object along a helical track and at the same time through or past the sensing member. 
   The helical track produces the desired rotational movement of the spherical object. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
     Preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings of which: 
       FIG. 1  shows a ball identifying device in accordance with a first embodiment of the present invention in which the balls are conveyed horizontally; 
       FIG. 2  shows a modification of the device of  FIG. 1 ; 
       FIGS. 3 and 4  show second and third embodiments of the present invention, in which the balls move vertically; 
       FIG. 5  is a perspective, partially cut-away, view of a ball identifying device in accordance with a fourth embodiment of the invention; 
       FIG. 6  is a top plan view of a track portion of the device of  FIG. 5 ; and 
       FIGS. 7 and 8  are perspective views of a fifth embodiment. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to the drawings,  FIG. 1  shows a ball identification device  10  comprising a helical screw  11  rotated about a horizontal axis by an electric motor and gear arrangement  12 . An electrical connection for the motor is shown at  13 . The helical screw is of a size suitable to receive a golf ball in its helical groove  17 . The screw passes through a cylindrical housing  20  which incorporates the sensing antenna coils in its walls. A connector for the antenna is shown at  21 . 
   In use, a golf ball (not shown in  FIG. 1 ) having a coded r.f. identification tag, is introduced via an inlet  25  and enters groove  17 . As the screw is rotated by the motor, the ball is constrained to move to the right of  FIG. 1 , past the antenna coils thus allowing the code of the tag to be read. Because the ball is constrained by the helical groove it is continually changing its instantaneous axis of rotation. This means that, even if in its initial orientation the ball&#39;s code cannot be read by the antenna, it is rotated into a new orientation in which it can be read before it leaves the region of the antenna. After being read, the ball then leaves via an outlet  26 . 
   An advantage of the above arrangement is that is prevents balls passing the code reading antenna without having their code read. In addition there is no need to stop the ball to have its code read. Any debris entering the inlet  25  passes straight through the device without jamming or damaging it. An advantage of the horizontal arrangement in underground locations, is that it minimises the depth of excavation needed to accommodate it. 
   Various modifications may be made to the above-described embodiment. For example, the axis of the screw may be arranged vertically. 
   The antenna coils may extend cylindrically around the axis of the helical screw or they may extend longitudinally along only part of the circumference thereof. 
     FIG. 2  shows a modified version  10   1  of the embodiment of  FIG. 1  incorporating a flap  30  which is biased by a spring (not shown) to pivot about a horizontal axis  31  in the direction of arrow  32 . As a first golf ball  41  begins to enter groove  17  it is engaged by the flap  30  so as to be urged leftwards. If there is an immediately following ball  42 , this is also urged leftwards against housing wall  29 . The result is that, as the helical screw  11  rotates (the face visible in  FIG. 2  moving upwardly), the ball  42  is constrained to travel on the raised part  18  of the screw, so that ball  42  cannot enter groove  17  until the screw has undertaken a whole rotation. This prevents ball  42  entering groove  17  simultaneously with, or immediately following, ball  41  which could cause jamming. 
   Another advantage of this arrangement is that it separates successive golf balls such as  41  and  42  in the conveying path. This is necessary for certain coding technologies, which are unable to reliably discriminate between immediately adjacent balls. 
     FIG. 3  shows a second embodiment of the present invention in which a ball identification device  50  has a helical screw  11  with a vertical axis, the balls travelling along groove  17  under the effect of gravity. The spacing between the screw  11  and the inner face of housing  20  is such that balls can travel to outlet  26  without jamming. This embodiment has the advantage of not requiring a power supply  13  since it has no moving parts. 
     FIG. 4  shows a third embodiment of the present invention in which a ball identification device  60  comprises a cylindrical core  62  with a helical track  63  located radially outwardly thereof in the manner of a helter-skelter. Again there are no moving parts, and a ball  61  travels freely along the track to outlet  66 . 
   The antenna can be arranged inside core  62  if desired. 
   The second and third embodiments are suitable for coding technologies which can discriminate between immediately-adjacent golf balls. However, if desired a ball separating device may be provided upstream to maintain a desired minimum distance between successive balls. 
   Referring now to  FIGS. 5 and 6 , a fourth embodiment of the ball identification device  80  comprises a generally cylindrical housing  81  with a helical track  82  located on its inner surface. The housing  81  may be constituted by a standard pipe fitting and its internal diameter is slightly larger than that of a golf ball. The internal diameter “d” of the track  82  as seen in  FIG. 6  is 3 mm less than that of a golf ball. Accordingly a golf ball passing vertically through the housing  81  is constrained to rotate to follow the track  82 . The pitch of track  82  is substantially 38 mm and it extends for substantially one and half turns. Track  82  may be formed integrally with housing  81 , e.g. by moulding, or may be a separate component attached to housing  81 . 
   Surrounding the exit of the housing  81  at the bottom is an antenna coil  85  for reading the code on a passing ball. 
   An advantage of the fourth embodiment is that it is generally compact and occupies less space than the third embodiment. In addition, the coded ball being read is enclosed within a housing and thus protected from external influences. An advantage of placing the detection coil at a spacing from the entrance to the housing is that, by the time the ball reaches the coil, it is undergoing a steady rotation with no tendency to slide. 
   In modifications, the housing  81  may be inclined to the vertical. It may also be oriented horizontally or near horizontally provided that there are means for assisting in moving the ball down the device, e.g. a blower for producing a moving air stream. The dimensions and materials may be changed as desired. 
   Referring now to  FIGS. 7 and 8 , a fifth embodiment of the ball identification device  90  comprises a tapering, i.e. frusto-conical, housing  91  with a helical track  92  incorporated in its inner surface. The housing is conveniently produced by a moulding operation. At its narrower, ball-receiving end the housing is provided with a locking ring  93  in the form of a bayonet fitting, which is arranged to be attached to a connector at the end of a conduit (not shown) for supplying a ball to the identification device. The conduit may be a pipe or a pocket of a target which is arranged to catch golf balls. 
   A housing  95  for circuitry associated with the ball identification device is attached to the locking ring  93  by means of a clip connection. Housing  95  has connectors  96  for enabling electrical connections to be made to printed circuit boards within housing  95 . In use, the exit end  97  of the housing  91  is arranged below the ball-receiving end so that balls descend through the housing under the effects of gravity. The antenna coil  98  is arranged upstream of the exit end  97 . Alternatively the antenna coil can be located within housing  95 . 
   The features and modifications of the various embodiments described may be combined or interchanged as desired. 
   The above-described ball identification devices can be used with other types of code-reading. For example bar codes or other optical codes can be detected by an optical reader arranged inside the housing of the device. An external reader can be used when the housing is transparent. The articles identified may be any other objects which roll. The articles need not be coded in which case the reader simply detects their presence.