GB1359793A - Rotary piston engine having a sealing strip - Google Patents

Abstract

1359793 Rotary positive - displacement machines DORNIER SYSTEM GbmH 6 July 1972 [4 Aug 1971] 31727/72 Heading F1F A radial sealing strip 1 of a trochoidal-type engine is lodged in the piston 2 and urged towards the casing 3 by a spring 10 and fluid pressure transmitted from either of the adjacent working spaces (depending upon which of these spaces contains the fluid at the greatest pressure) through a bore 6 or 6<SP>1</SP> past a corresponding valve plate 7, which is biased towards its closed position by a spring 8. Leakage past the strip is prevented by a sealing element 9. The centre of curvature of the head of the strip is at the point S of intersection of the trochoid T and the envelope curve, which coincides with the peripheral surface of the piston. A second embodiment, Figs. 2a and 2b, (not shown), differs in that the valve plates are replaced with two axially abutting valve elements each of which is similar to the element 9, the axes of the bores 6, 6<SP>1</SP> lie in two parallel transverse planes and communicate with the undersides of the valve elements through respective radial bores, and two sealing elements resembling the valve elements replace the element 9, the spring 8 being dispensed with. A third embodiment, Figs. 3a and 3b, (not shown), differs in that the strip is lodged in the casing and divided obliquely into two parts, and there are bores and valve elements similar to those of the second embodiment. The latter embodiment may be modified in that the groove and bores are formed in a partly cylindrical insert instead of the body of the casing, Fig. 4, (not shown).