Patent GB-983298-A (GB)
Title: Bowling alley surfacing machine
IPC: A47L11/202
Filed: 1961-05-09
Abstract: 983,298. Surfacing bowling alleys. AMERICAN MACHINE & FOUNDRY CO. May 9, 1961 [May 31, 1960], No. 16855/61. Heading B3D. [Also in Divisions F4 and G3] A machine for surfacing a bowlling alley includes a frame having means thereon for supporting the machine for movement along an alley; two rotatable drums mounted on said frame transversely thereof and adapted to mount therearound an endless abrading belt serving as surfacing means for the bowling alley; means for driving said belt; pressure means between said drums operable in use to press the belt against the alley surface and means whereby the pressure means can be adjusted to a horizontal position in a direction transverse to the direction of movement of the belt thereunder. A machine, Figs. 1, 2, 4, comprises a frame having parallel side members 4, 5 interconnected at their ends by cross-members 6. Near the rear end of the frame rocker arms 14 are pivoted to the side members 4, 5 and carry an axle 16 to which is keyed one or more supporting wheels 17. Each rocker arm 14 has bearing on its rear end a screw 18 threaded in the frame and connected by a universal coupling 19 to a rod 20 rotatable by a handle 21 to adjust the position of the frame relatively to the alley surface 10. Tubular members 22 secured to the rear end of the frame are pivotally connected at their upper ends to a cross-member 23 serving as a handle-bar for the operator. A rod 26 rigid on the handle 23 is in threaded engagement with a sleeve 28 supported at its lower end on a plate 30 on which is mounted a wheel 25; brace members 31 are provided. A spirit level 32 is mounted on the frame. A plate 35 spans the side members 4, 5 at the rear end of the frame. Forwardly of the plate 35 is a drum 36 on a shaft 37 mounted in bearing blocks secured to the side members 4, 5. The shaft 37 is driven, through belts 66, by electric motors 61 mounted on supports fixed to the plate 35, the centres of gravity of the motors being located rearwardly of the axle 16; a single motor may be used. An endless belt B of sandpaper or emery cloth as least as wide as the alley surface 10 is mounted on the drum 36 and on a drum 40 near the front end of the frame, having a shaft whose ends are received in bearing blocks 42 movable in slots 43 in bracket 44 secured to the side members 4, 5. Each block 42 is adjusted by a screw 45 rotatably connected thereto, extending through a fixed nut 46 and connected by a universal coupling 48 to a rod 49 rotatable by a handle 52. To permit installation and removal of the belt, the frame is hinged in four places by two hinges 59 at each side of the frame, each hinge including a removable pin 60 so that upon removal of the pins at one side of the frame the latter can be swung open. A rough sanding belt may be used first and then replaced by a finishing sanding belt. An intermediate drum 54 has a shaft journalled in bearing blocks secured to the side members 4, 5, the drum being slightly lower than the drums 36, 40 so that it presses the lower run of the belt B against the alley surface 10. If area contact between the belt B and the alley surface 10 is desired, e.g. when finish sanding, a presser member P is mounted beneath the drum 54. The member P may be of aluminium with a polished steel facing and is secured to a rod R having its ends removably received in openings 73 in the side members 4, 5. When rough sanding, the drum 54 should exert a force of about one hundred pounds on the alley surface 10; when the member P is used, the force should be about forty pounds. The desired force is obtained by adjustment of the sleeve 28. To cause the machine to travel along the alley, the axle 16 is driven, through a belt 71 and a speed reduction unit 68, by a reversible electric motor 67 mounted on the plate 35. Guide means for maintaining the machine in such position on the alley as to ensure finishing the alley surface across its entire width as the machine travels along the alley comprises wheels 77 vertically adjustable on arms 74 projecting from the frame, the wheels engaging parts of the alley on both sides of the alley bed. The rear cross-member 6 has openings to accommodate suction tubes 80 each connected to a suction pump 81 mounted on a cross-bar 82 and discharging into a removable dust bag D. In a modification. Fig. 5, screws 85, 86 are threaded in blocks 87, 88, fixed on the side members 4, 5. The lower ends of the screws bear against the rocket arms 14 and the screws are rotated through bevel gearing 89, 93 and 90, 94 and a belt 97 by a reversible motor 100 mounted on the plate 35. When the motor 100 operates, the screws are rotated in opposite directions so that one wheel 17 is lowered and the other is raised. Operation of the motor 100 is controlled by a pair of mercury switches operating through relays, non-horizontal positioning of the frame causing the mercury of one or the other of the switches to effect operation of the motor to raise the low side of the frame and lower the high side until the frame is horizontal.