GB216549A - Improvements in rotary pneumatic tools - Google Patents

Abstract

216,549. Conklin, B. Jan. 26, 1923. Drilling-machines. - A pneumatic rotary engine of the rotary vane type is coupled directly or by gearing to a rotary tool such as a drill and is provided with a distributing valve entirely within the inner element of the engine. Packing washers of varying thickness may be used to adjust the degree of admission through the valve ports. An outer stationary casing a, Fig. 2, carries abutments i, Fig. 1, which co-operate with rotary vanes f carried by an inner rotary member c, recesses g in the vanes allowing them to pass the abutment. Motive fluid is admitted by a pipe b to the interior of a distributing valve m whence it passes through ports k and passages j to the working spaces d. The exhaust passes through ports o and passages p to the outlet r. The vanes f are rotated by aear-wheels t meehing with a toothed ring u carried by the outer casing- Handles y are provided for manipulating the arrangement. A drill &.c. may be attached to an extension t'. In a modification, the outer member carrying the abutments rotates and the innermember carrying the rotary vanes is fixed. In this form one of the hollow handles is used as an inlet pipe and a shield is provided to direct the exhaust away from the operator. In a further modification, the exhaust ports are formed in the abutments themselves. In the construction shown in Fig. 7, the valve is arranged to allow the direction of rotation to be reversed. The valve ports h<1>, j<1> are formed in a member n which is moved by the pressure of the motive fluid to reverse the direction of the fluid through passages g<1>, j according as fluid is admitted above or below the member by the interchange of the inlet and outlet connections b, p<1> by movement of a handwheel k<1>. If the positions of the inlet and outletare reversed in Fig. 7, the member n moving downwards will connect the upper port h<1> with the passage g<1> and the lower port j<1> with the passage j. Specifications 14446/96, [Class 79, Locomotives &c.], 13743/14, [Class 110 (ii), Rotary engines &c.], and 106,209, [Class 7 (v), Internal-combustion engines, Starting &c.], are referred to.