Patent GB-328407-A (GB)
Title: New or improved instruments for determining the quality of balls for games and components therefor
IPC: G01M99/00
Filed: 1929-04-02
Abstract: 328,407. Cropper, T. April 2, 1929. Testing physical qualities of materials. - An instrument for determining the quality of playing balls such as tennis balls or golf balls, and ball components comprises a clamp to engage the ball, means to load said clamp resiliently with a load applied in two stages, load applying means, and means to determine the movement of said loading means with or without means to indicate when either or both stages have been applied. In the form shown in Fig. 1, the ball 21 is placed between two anvils 18, 14 mounted within a hollow frame. Both anvils can slide without rotating relatively to the frame, the stem of the anvil 14 sliding with a sleeve 9. To make a test, the screw 3 is turned to apply through the anvil 18 a pressure to the ball, the anvil 14 being thus moved to compress a light spring 7. Sufficient initial pressure is indicated by the operator being unable to turn by light manual effort a knurled washer 16 held between the anvil 14 and a collar 8 on the sleeve. A loose indicating sleeve 19 is then adjusted so that the pointer 20 reads zero. The screw is then further rotated until the heavy spring 6 around the sleeve 9 is compressed sufficiently to allow a knurled collar 11 to become loose. The amount of movement of the screw is read off from the graduated ring 19. In a modified form both discs 11, 16 are arranged at the left-hand of the instrument and are respectively freed upon application of each load. In a third form, Fig. 4, the anvil 26 is pinned to the sleeve 38, and normally the disc 40 is held against stops 42. At the end, the disc 36 is arranged on a sleeve 30 carrying the anvil 25 and screw 3, and between the walls of a screen in the frame. The screw thus has limited movement and on excessive loads either initially or finally the discs cannot be turned. A blade spring may be used in this form instead of the spring 28. In a fourth form, both discs surround the stem of the anvil opposite the screw-moved anvil and are arranged one within the other. Each is provided with a finger piece attached to the frame by a spring so that the discs or washers are turned by the spring when released. In the form shown in Fig. 8, a bridge piece 68 is formed in one with the boss 67 and supports rods 69 securing a web part 70. One disc 72 is rotatable about a spigot 73 located in the web, and the other disc 71 about one rod 69, the complementary anvil in this case being a flexible beam 74 positioned by the rods 69 upon a washer 75. In the form shown in Fig. 9 parts of the frame are of spring formation. The arms 76 connect bosses 77, 78, in the former of which is housed an anvil 79 with a stem engaged by a spring surrounded by a sleeve 82 acted upon a screwed member 3. A knurled disc 83 is mounted on the stem 80. The boss 78 forms one anvil and has below it a support 84 rigidly connected by a web 85 with the boss 77. A knurled disc 86 is arranged between the boss 78 and part 84. In a further form the anvil is formed on one end of the open frame and only one disc is employed. In the form shown in Fig. 12, one of the anvils is constituted by a beam 105 mounted upon a displaceable fulcrum 11 urged against the beam by a spring 110 the beam being forced against circular indicator members 106, 107 bearing against lugs 108 on the irame. The initial reading is taken when the beam engages a stop 112 indicated by permission of rotation of member 107. The fulcrum 111 is offset from the indicator 106 which is released when the main load is reached. In a further form a second fulcrum like 111 is used instead of the stop 112. In still further forms of which Fig. 16 is an example, the first stage of the load is applied independently of the second stage. The anvil 120 is moved by a head 124 within which is a spring- loaded tooth adapted to engage serrations 123 on the end of the screw 122 in such manner that positive engagement only occurs in one direction, the drive in the reverse direction being effected frictionally by the force of the spring only. This drive is used to apply the initial load. The stem of the other anvil 130 passes through a sleeve having a flange 134 and is secured by nuts. A hollow headed hand lever 138 pivots about a pin shown in dotted lines and depresses the flange 134 and sleeves against the influence of a spring 136. The flange 134 carries an indicator plate 140 on which is a pointer 142 the pin of which is connected by a pivoted link to the anvil 130.