Patent GB-246206-A (GB)
Title: An improved rotary fluid pressure engine or motor adapted to operate, or combined with means for operating, a drill or other rotary tool or appliance
IPC: B23B45/04
Filed: 1924-10-20
Abstract: 246,206. Keay, R. W. Oct. 20, 1924. Fixed-abutment type; movable-abutment type; balancing moving parts. - In a rotary engine operated by fluid pressure as, for example, compressed air, and comprising a plurality of rotary chambers each consisting of a rotary piston concentrically mounted in a stationary casing, with a piston element adapted to engage a fixed or pivoted abutment, working clearances are provided between the end faces of the rotors surrounding the bearings located adjacent to the shaft to which the rotors are keyed, and between the abutments, pistons and casing, so that there is no appreciable friction tending to decelerate the motor except during contact of the pistons with the abutments. The engine is stated to be applicable for operating such rotary machine tools as drills, reamers, tube expanders and the like, and is asso. ciated with suitable gearing for this purpose. In the arrangement shown in Figs. 1 and 2, two rotary engines each with a rotor 1 carrying a piston 2 engaging a pivoted abutment 4, are provided in the annular chamber 3. The rotors are keyed to a shaft 8, the pistons are arranged at 180‹ to one another, and inlet and outlet ports 7, 9, for the compressed and exhaust air respectively are provided. Each piston chamber consists of an annular casing 10 with a thickening at 11 to provide a recess for the pivoted abutment 4 and for the ports. Bearing bushes 13, 20 are provided adjacent the shaft at the end plates 15, 16 and the dividing plate 14. A shoulder 22 is provided so that the free ends of the abutments are just out of action contact with the peripheries of the rotors, and the pistons 2 are so formed that their surfaces have a slight clearance with the inner periphery of the casing 10. A similar clearance is also provided between the end surfaces of the pistons and the end and dividing plates 14 - - 16, and also between these plates and the end surfaces of the rotors. It is preferred that fhe bushes 13, 20 be in fairly close contact to maintain the rotors in position. Clearance is provided where a pivoted piston 2<c> and fixed abutment 4a is used, as in Fig. 10. Where the rotors are of aluminium or other light metal, the piston bodies may be balanced by bodies 24 of lead. The shaft spindle 8 is formed hollow to serve as a reservoir for lubricant, which is delivered to the bearings through ports 25. For a pneumatic drill, the inlet port 7 for the compressed air may lead through a port 7<c> to a throttle valve controlled by a pistol-grip handle 26 or by a feed-screw device. Relative movement between the rotors and motor spindle is provided to prevent undue wear. Ball races 33<b>, 33 are also provided. The lower end of the shaft is equipped with a tool holder 27. As shown in Fig. 5, the tool holder is driven through gearing 29 - - 31 enclosed in a gear-box 32 secured by bolts 19. The spindle of the gear-wheel 30 is mounted in plates 16, the gear 29 is keyed to or integral with the spindle, and lubricant is supplied to the gear-box.