Patent GB-1211090-A (GB)
Title: Balancing devices for rotatable objects
Inventor: BJORN THOMAS EDWARD
IPC: G01M1/36
Filed: 1967-12-22
Abstract: 1,211,090. Balancing vehicle wheels. STEWART-WARNER CORP. 22 Dec., 1967 [27 Dec., 1966], No. 58454/67. Heading F2U. [Also in Division G1] A balancing device for use in determining the rotary imbalance of vehicle wheels in situ comprises a mounting ring 14 for securing the device to a vehicle wheel 12 and on which are mounted two counterbalance weights 84, 86 for rotation about an axis 91 parallel to and displaced from the axis of rotation of the wheel 17, the weights 84, 86 being adjustable simultaneously in opposite rotational directions to counterbalance any imbalance in the vehicle wheel whilst the wheel is spinning. The ring 14 carries a housing 40 having a central aperture in which is journalled a bearing plate 48 carrying all the gearing elements shown in the drawing. The whole assembly normally spins with the wheel 12 but the bearing plate 48 may be controlled manually so as to make it rotate relative to the housing 40 to adjust the position of the resultant weight of the two weights 84, 86 round the wheel. The weights 84, 86 are also adjustable about their axis 91 to vary the resultant weight from a minimum to a maximum value. Preferably the minimum value is zero, the centres of gravity of the two weights coinciding with the axis 17. Rotation of the plate 48 with respect to the housing 40 is effected by pushing or pulling a knob (not shown) on a shaft 104, this causing a core clutch 102 to hold stationary either a gear 96 meshing with a gear 118 keyed to a shaft 121 to rotate the shaft in one direction, or a gear 94 meshing with an idler gear 114 also meshing with the gear 118 to rotate the shaft in the other direction. The shaft 121 carries a worm-wheel 124 and this drives a pinion 136 engaging with a ring gear 138 on the housing 40. Thus if the wheel 12 is spinning the plate 48 can be made to rotate relative thereto in either direction by pushing or pulling on the shaft 104. Simultaneous equal and opposite rotations of the weights 84, 86 about their axis 91 can also be effected by pushing or pulling on a shaft 108 having a cone clutch 106 holding stationary either gear 98 or gear 100. Thus by pushing or pulling on the shaft 108 the effective resultant weight of the two adjustable weights 84, 86 can be increased or decreased. This resultant weight is indicated by a scale marked on an indicator 62 driven by a gear 158 from the drive for the weights 84, 86. A hairline is provided in a window 68 to enable this weight to be read off. A pointer 66 indicates the circumferential position of the resultant weight and thus the position at which counterbalance weights must be applied to the wheel 12. In use the operator adjusts the weights 84, 86 with the wheel spinning to select say a resultant weight of 2 oz. This is indicated by a coloured area 80 becoming visible in a window 70. The plate 48 is then rotated relative to the wheel to find the position of least vibration, and the weights 84, 86 are further adjusted to increase or decrease the resultant weight to again minimize vibration. After successive adjustments the magnitude of the balance weight can be read off on the indicator 62 and the position on the wheel to which it should be applied is given by the pointer 66. If desired the weights 84, 86 can be arranged to rotate about separate axes parallel to the axis 17.