Patent GB-1218524-A (GB)
Title: Improvements in and relating to wheel balancing devices
Inventor: HAYNES DON ALTON
IPC: G01M1/12
Filed: 1969-02-18
Abstract: 1,218,524. Balancing machines. FMC CORP. Feb. 18, 1969 [Feb. 20, 1968], No.8671/69. Heading G1X. A wheel balancing device comprises a base 12, a head 13 pivotally mounted on the base on bearings 21, a shaft 14 journalled in the head in bearings 15 the shaft carrying a plate 30 to receive a wheel 35 for balancing, unbalance of the wheel inducing oscillation of the shaft 14 which is indicated by movement of a disc 47 in a plane at right angles to the axis A of rotation of the shaft 14, to a position eccentric to the centre of the shaft in accordance with magnitude and position of the imbalance in the wheel. The pivotal axis of the head 13 on the base 12 is preferably at an angle of 45 degrees to the axis of the shaft 14. The disc 47 which is annular in shape is mounted between members 41, 44 on the shaft 14, a spring 48 acting on the member 44 to hold the disc 47 in position but not so tightly as to prevent movement of the disc 47 normal to the shaft 14 upon the application of a significant force thereto. This end of the shaft 14 also carries a male core clutch member 59 engageable with a female clutch member 68 which is movable towards and away from the member 59 by links 73, 92, 89 actuated by a handle 87 movable between the full line and dotted line positions shown in Fig. 3, the clutch member 68 when engaged with the member 59, as shown, serving to clamp the disc 47 securely between the members 41, 44. Movement of the handle 87 also pivots a member 100 about a shaft 101, the member 100 at its free end carrying a flapper plate 110, Fig. 9 pivotally mounted about the axis of a pin 113. The shaft 101 is canted so that progressive movement of the handle 87 towards the dotted line position of Fig. 3 lowers the flapper plate and brings it close to the shaft 14. In this way it contacts the disc 47 and pushes it to a position eccentric to the shaft 14 upon oscillation thereof. In use a wheel 35 with plate 30 statically balanced by allowing free rotation of the shaft 14 under the effect of gravity on the wheel. The wheel is then rotated to speed by a wheel spinner (not shown) and the cane clutch is cleared by movement of the handle 87 allowing shaft 14 to oscillate under the action of any unbalance present in the wheel assembly. The flapper plate 110 engages the disc 47 as it rotates pushing it out of centre with regard to the shaft 14 until as the flapper plate moves progressively inwards towards the centre it reaches a point where the plate is touching the disc at all points round its circumference. A long feeler member 120 visible to the operator is connected to the flapper plate and when this member stops vibrating, the above desired condition has been reached. The core clutch is then engaged and the wheel stopped by engagement with the handle 87 The upper part of the handle 87 is shown in Fig. 10 and this includes a dial gauge 131 having an operating plunger 151 engaging with a rod 153 carrying a sensing finger 152 Fig. 3 at its lower end. By rotation of a knob 147 at the top of the handle 87 a plunger 143 is moved downwardly also moving the dial gauge 131 and moving the finger 152 into contact with the disc 47. By slowly rotating the wheel 35 by hand the position of maximum deflection on the dial gauge can be found, this giving the position of unbalance and the reading of the gauge gives the magnitude of the unbalance, the dial being calibrated to read in ounces weight necessary to restore balance to the wheel.