GB1020537A - Rotary piston machines - Google Patents

Abstract

1,020,537. Rotary engines, pumps and compressors. NSU MOTORENWERKE A.G. & WANKEL G.m.b.H. Dec. 10, 1962 [Dec. 9, 1961], No. 46540/62. Heading F1F. In a rotary-piston I.C. engine of the trochoidal n and n+1 lobe type, a radial sealing-strip 28 (Fig. 2, not shown) is lodged in a groove 26 at each apex 12 of the piston 10 and a shoe 30 is pivotally mounted in a recess 34 adjacent each strip, one end of the shoe being in sliding contact with the inner peripheralsurface 4 of the engine housing. The strip is biased outwardly by a spring 46 located in an intermediate sealing-body 34 which is situated between lateral sealing-strips 22 on each end face of the piston. Clearance is provided between strip 28 and slot 26 to give gas access to the under side of the strip. Gas enters slot 26 through holes 48 in the shoe (Fig. 3, not shown) or wedge-shaped gaps between end walls 1, 2 of the housing and tapered lateral-edges 31 on the shoe, the shoe being pressed outwardly by a leaf spring 61 and gas pressure exerted on its outer end when the pressure in a working space B exceeds that in an adjacent working space C. The shoe may be modified (Fig. 5, not shown) in that it is pivotally attached to the piston by screws 56. Alternatively, the shoe may be made of flexible material (Figs. 6, 7, not shown) e.g. spring steel, one end of the shoe being attached to the piston by screws (not shown) or lugs 60, 62 lodged in grooves 64, 66. The shoe may be provided with two lobes or crests 68 (Fig. 8, not shown) which slide on the surface 4, or the shoe may comprise two parts 65<SP>1</SP>, 67<SP>1</SP> (Fig. 9, not shown) made of rigid material and pivotally attached to one another. The part of the shoe which is in contact with the sealing strip may be of part-spherical shape (Fig. 4, not shown). The invention is applicable to other kinds of rotary-piston machines e.g. pumps or compressors.