Patent GB-734031-A (GB)
Title: Gauging device
IPC: G01B13/02
Filed: 1952-11-06
Abstract: 734,031. Linear-dimension gauges. SHEFFIELD CORPORATION. Nov. 6, 1952 [Feb. 26, 1952], No. 27968/62. Class 106 (2). A gauging device for comparing the size of a workpiece with a standard comprises a pair of opposed anvils for contacting the surface of a workpiece at spaced intervals, one anvil being secured to a base and the other movable toward and away from it, means defining a fluid discharge orifice mounted in fixed relation to the base and means movable with the movable anvil for limiting in accordance with the workpiece dimension the flow of fluid through the orifice defining means when the movable anvil is moved toward the stationary anvil and into contact with the workpiece. The flow of fluid which is a measure of the required dimension may be visually indicated by a float in a glass bore tapering towards the bottom to which air at constant pressure is supplied at the lower end and from which it passes at the upper end to the gauging device through a tube 15, Fig. 4, tolerances being indicated by setting adjustable indicators on a slide adjacent the bore. As shown, Figs. 2, 4, the gauging device comprises a base 20, preferably of cast iron, formed with machined pads 21, 22 and a groove 23 for receiving a reference block 24, held by bolts 25. An anvil-supporting block 28 is located by two pins 32 and clamped by two bolts 33 on the pad 22. The block 28 and an extension 30 have finished faces 29, 31 against which an anvil can be drawn by a clamping bolt in an inclined tapped hole 34. The top of the block 28 is provided with a finished face 36 which is recessed to receive a nozzle 37 supplied with air from the visual indicator by the tube 15 connected to a nipple 41 in an aperture in the base 20 registering with a horizontal passage 39 in the block 28, with gasket 40 for sealing, and communicating with a vertical bore 38. A relief channel 42 is milled in the face 36 adjacent the nozzle 37. Co-operating with the nozzle 37 is a pin 45 carried in the forward end of a gauging arm 46. To provide a substantially frictionless bearing without play for the arm 46, Fig. 5, it is reduced in width from a step 47 towards the rear to accommodate a spring tongue 48 rigidly secured thereto by two locating pins 49 and two screws 50. At their rear ends the arm 46 and spring 48 are bored to receive tenons on the inner ends of two hubs 51 axially aligned between two lugs 52 upstanding from the base 20 and bored'to receive plugs 53 axially adjustable within the bores by set screws 54 with conical points engaging conical recesses. The inner end of each plug 53 has a spherical, recess seating a ball 55 and the outer end of each hub 51 has a raceway for balls 56 eaged by a pin 57 in an axial bore and a cap 58 over the outer end of the hub having an aperture to receive the ball 55. A T-shaped operating arm 6'5 is pivoted about the same axis as the arm 46 by means of' two screws 66 with conical points engaging conical seats in the plugs 53 rand locked after adjustment by nuts 67. The arms 46, 65 are operatively related with lost-motion provided by a pin 68 supported in depending flanges 69 passing through a larger bore 70 in the arm 46 and spring 48 so that. the arm 46 may be raised or lowered by means of the arm 65, which has a pressure pad 75, Fig. 4, for the operator's hand, normally biased upward by a spring 76 stretched between a pin 77 at the rear end of the arm 65 and a pin 78 at the rear of the base 20. Upward movement of the arm 65 is limited by the engagement of the lower, inner edge of its rear end with the lugs 52 and downward movement is limited by the engagement of a pin projecting downward from the flange 69 with a screw 80 locked by a nut 81 after adjustment. In some gauging operations the arm 65 is depressed against the action of the spring 76 to this lower limiting position and held there by means of a bar 84 pivoted about the pin 78 and slotted near the top to engage the pin 77, a pin 86 limiting movement of the bar 84 when swung away from the pin 77 to unlock the arm 65. As shown in Fig. 7, the gauging device is set up to provide a two-point check of the diameter of a race 95 in a cone 96 of ball bearing. An anvil 90 with a gauging pin 97 for bearing on the top of the race 95 is clamped by a bolt 89 in an elongated, shouldered slot 88 at the forward end of the arm 46 and lies above an anvil 91 with a gauging pin 98 engaging the bottom of the race and clamped against the block 28 by a bolt 92 in the inclined hole 34. When the arm 65 is depressed, the arm 46 will move down under gravity till the pin 97 contacts the race 95 while the pin 45 moves down over the nozzle 37 to restrict the flow therethrough and the float will indicate any deviation of the race from a standard, shown by the indicator with a master cone between the anvils. The elongated slots 88, 93 facilitate horizontal and vertical adjustment of the anvils 90, 91 respectively for the particular part to be gauged and the anvil 91 preferably has locating surfaces 100, 101 permitting the use of gauge blocks between them and the reference block 24. The pin 45 may also be adjusted up or down after loosening a clamping screw 102, Fig. 5, thereby releasing clamping collars 103. To facilitate the gauging of large numbers of cones 96 a work-supporting arm 105, Fig. 7, may be provided journalled on a pivot bolt 106 in an aperture 35, Fig. 2, of the block 30 and provided with an arbor 107 to receive the cones 96 in succession. After placing a cone on the arbor 107, the arm 105 is rocked rearwardly to bring 'the race 95 between the pins 97, 98, a stop pad 109 on the anvil 91 limiting rearward movement. The screw 80 must be previously set so that when a part being gauged is between the anvils, there is clearance between the pin 45 and nozzle 37 and also between the pin 68 and hole 70 so that the gauging arm 46 will be free to move up and down independently of the operate ing arm 65 and the pressure of the anvil 90 against the part being checked will be due solely to the force of gravity acting on the arm 46. When gauging parts with the aid of the arbor 107, the arm 65 should preferably be locked in lowered position by means of the bar 84. As shown in Fig. 6, the gauging device is set up to check the Internal surface of a race 116 in a bearing cup 115 placed over gauging ribs 117, 118 carried respectively by a block 121 held by a bolt 122 on an anvil 119 bolted to the block 28 and by an anvil 120 clamped to the arm 46. The lock bar 84 is disengaged and the spring 76 raises the arm 65 until the upper edge of the arm 46 abuts the underside of the block 121, bringing the nibs 117, 118 together. After a cup 115 is placed over the nibs 117, 118, the arm 65 is depressed to bring the pin 79 into contact with the screw 80 causing the arm 46 to bring the nib 118 into contact with the bottom of the race 116 while the nib 117 will contact the race 116 at two points above the centre thus effecting a three-point check. The gauging device is also shown set up with several different sets of anvils for checking other internal and external dimensions.