GB657726A - Improvements in or relating to floor polishing machines - Google Patents

Abstract

657,726. Floor polishers. PATCHETT, G. W., and STERLING ENGINEERING CO., Ltd. March 11, 1949, No. 6746. [Class 138(i)] In an electric floor polisher of the type having two or more rotatable brushes, drive is transmitted frictionally from the motor shaft to one or more brush-carrying wheels, and from such wheel or wheels to one or more further brush-carrying wheels by an encircling driving belt, the bearing of each brush-carrying wheel being mounted eccentrically and being spring-urged in a direction to maintain the friction drive and tension the driving belt. Means are preferably provided for interrupting the frictional drive from the motor shaft when the handle is raised to a vertical inoperative position and for releasably locking the handle there. The polisher comprises a handle 12 terminating in a fork 10 the ends of which are pivoted to the brackets 9 on the casing 3 which encloses the brushdriving mechanism. The handle can be locked in a vertical position by a spring loaded plunger mounted on the bottom of the handle and which engages a detent 57 on top of the motor casing 2; the catch being releasable by depression of pedal 53. The motor spindle 17, Figs. 5, carries a driving pulley 18 which frictionally drives brush-carrying wheel 4a, fitted with a rubber tyre 29. Brush wheels 4b and 4c are driven from wheel 4a by a belt 59. The bearing of each brush wheel is carried by an eccentrically mounted bush 22, Fig. 6, which is rotatable on the fixed pin 24, so that rotation of the bush about its pin moves the wheel 4 laterally. Each bush is passed round a part of each peripheral formed with a peripheral groove 23 and has a pin 23a projecting radially from the groove. As shown in Fig. 5, a tension spring 30 or 31, anchored at one end, is groove and attached to the radially projecting pin 23a or 32 in such a manner that the springs tend to rotate the eccentric mountings to urge the wheel 4a against its driving pulley 18 and to urge the wheels 4b and 4c outwardly to tension the belt 59. When the handle 12, Fig. 1, is raised and latched in its vertical position, the drive between motor pulley 18 and wheel 4a is interrupted. This is effected by means of a projection 42 on the fork 10 which in the vertical position of the handle engages the flange 35 of two-armed lever 34, 36, Fig. 5, and moves the arm 36 against spring 39 to engage the radial pin 32, whereby the pin 32 and its eccentrically mounted bearing are moved so as to separate the wheel rim from its driving pulley 18.