Patent GB-191462-A (GB)
Title: An improved pneumatic-tyre calliper-gauge
IPC: G01B3/24
Filed: 1921-10-11
Abstract: 191,462. Frost, W., and Frost & Co., Ltd., H. Oct. 11, 1921. Linear-dimension gauges. - An adjustable caliper-gauge for inflating a pneumatic tyre the correct amount comprises a double-ended pair of calipers having arms 15, 16, pivoted at 14 so that the distance between the points 18 is greater in a predetermined ratio than that between the points 17, this ratio being different for various makes of tyre and being determined by the manufacturers. Assuming that the tyre is deflated the points 17 are applied to a portion of the tyre which is not in contact with the ground to measure the maximum width of the outer cover. The tyre is then inflated until the maximum width of the tyre where it rests on the ground is equal to the distance between the points 18. In a modification, Fig. 3, the second size measured by the calipers is increased by a definite amount irrespective of the distance between the points 25. The first measurement above-mentioned is taken with the pivot 23 at the left-hand end of the slot 22, the block 24 carrying the pivot 23 being then adjusted to the right-hand end of the slot 22, thus adding to the distance between the points 25 by a definite amount. In Fig. 2 the said ratio is altered by means of the slot 19 for different makes of tyre and in Fig. 3 the said predetermined amount is altered by stops (not shown) which limit the amount of movement of the block 24. The second dimension to be measured by the calipers may vary according to the load on the vehicle and to compensate for the consequent alteration in the maximum width of the tyre where it touches the ground a block: 35, Fig. 5, co-operates with a pin 36 on the arm 32 so that the three dimensions of this block may be used according to the load. 191,497. Wennergren, E. R. Oct. 17,1921. Linear.dimension gauges.-Relates to apparatus for gauging machine parts accurately and comprises a base supporting adjustably members upon which slide the, runners between which the measurement is made. In the form shown in Fig. 1, a base 1 carries an upright 4 sliding upon it as adjusted by a screw 24, a standard piece being interposed if necessary, the upright being graduated to take a sliding runner 13 with a rocking contact member 14 with a surface ground accurately plane. A second upright 20 is secured to the base 1 by a screw and nut 18 and is adjustable in inclination and locked by a screw 21, the angles being further secured by a slotted link 22 pivoted to it and secured in position by a screw 23 to the upright 4. In use the angle of the upright 20 is fixed and the upright 4 slid 'up to it until the piece 14 is in contact, the runner being adjusted with its pointer 17 at, say, zero on the scale. The piece 14 is then locked and the runner is placed with the pointer 17 at a reading such as " 10," at which the distance between the piece 14 and the upright 20 is very accurately the required distance to be tested. To ensure accuracy between the gauging surfaces, a runner 25, Fig. 5, with accurately ground surface 27 may be mounted to slide on the upright 20 under the control of a rod 26 attached to the runner 13. In a modified form greater accuracy is allowed by making both uprights adjustable as to angles around pivots 36, 41, Fig. 6, respectively, by means of screws 39, 44 the adjustment being clamped by screws 37, 42. The uprights are formed of two parts as shown at 34, 35, Fig. 7. The rod 48 for maintaining the uprights 31, 34 in relative position is pivoted to the latter and is clamped to the former by a screw 50, on which a lever 51 is adjustably secured so as to release the clamp on operation of a rod 53. The rod 61 for moving both runners together is connected by a cord over pulleys to a counterweight. In a further modificaticn the members 72, 73 supporting the runners 57, 58 are secured adjustably in an approximately horizontal position in a framework built up of a base 28, uprights 74, 75 and top member 76. To prevent bending of the members 72, 73 during use the former bears against a strut 83 adjustable on the top frame member, and the latter rests against a fixed stop 78. The angle between the members 72, 73 is adjusted by means of accurate distance pieces placed between plane ground surfaces 91 on the upper member and plane surfaces 86 on cylinders 87 swivelling in bearing shoes 88 attached to the lower member. To facilitate accurate adjustment of the runners a weight 95 is connected to them by a cord over pulleys.