SE7407610L - - Google Patents

Abstract

1447607 Rotary positive-displacement fluid-machines ARTHUR D LITTLE Inc 10 June 1974 [11 June 1973 23 Oct 1973] 25695/74 Heading F1F A machine of the intermeshing-scroll type, which can be used as a pump, compressor or expander, has co-operating "scroll members" 25, 30, Fig. 7, comprising spiral elements, or "wraps", 10, 12 on end-plates 26, 31, the member 25 being stationary and the other member being moved orbitally about the axis of the member 25 without revolving about its own axis by mechanism including a circular element, or "driver", 35 engaging with a ring 36 through an elastomeric sealing ring 52 and mounted on a bearing 47 disposed eccentrically on a rotary driving shaft 56. The mechanism while moving the member 30 orbitally reduces at least partially the resultant radial force on the member due to radial acceleration, Figs. 6A and 6B (not shown), so as to minimize wear on the lateral surfaces of the wraps. Axial loading to reduce leakage across the end surfaces of the wraps may be effected by fluid-pressure transmitted to a chamber, or "volume", 54 from a high-pressure zone 33 through a port 55 and by a spring 53. To prevent the member 30 revolving about its axis a coupling member 70, Fig. 8, may engage with enlarged inner sections 62ÀÀ65 of the wraps of the two scroll members, cut-outs and recesses 80, 86, 87 giving the working fluid access to an outlet port 21. An inlet port 100 may be located where shown in the end-plate 26. Alternatively, rotation of the orbital scroll member is prevented by a ring 144, Fig. 10, with channels engaging with radial extensions 155 .. 158 on the wraps of the two scroll members. In another embodiment, Figs. 13 and 14 (not shown), high-pressure working fluid passes intermittently through an outlet port (279) controlled by an enlarged inner section (282) of a single wrap on the orbital scroll member. In a further embodiment, Figs. 15 and 16 (not shown), both of the scroll members revolve about axes thereof and move orbitally relative to each other. In yet another embodiment, Fig. 17, one scroll member 71 is anchored by a bolt 211 allowing it to move axially and to a limited extent circumferentially into an optimum position, the other scroll member 81 being connected to a driving shaft 244 by a pivoted rod 248. To reduce the resultant radial load on the member 71 the rod 248 may be spring-loaded, Fig. 30 (not shown), or furnished with a counterweight (167), Fig. 32 (not shown). Rotation of the member 81 is prevented by a pair of radial keys 101, 235 fixed thereto and further pair of radial keys (106, 107), Fig. 27 (not shown), fixed to a housing flange 230, these pairs of keys sliding in respective keyways (231ÀÀ234), Fig. 24 (not shown), in an annular member 225, which is lubricated through a passage 116. Instead of the rod 248 the member 81 may be connected to the shaft 244 by a transversely-sliding block (183), Figs. 33 to 35 (not shown), which is counterbalanced by a spring (186) or a weight (190) to reduce the resultant radial load on the member 71. Counterweights (170, 173), Fig. 36 (not shown), may be fixed to a "crank" 246 to reduce vibrations. To reduce friction the member 225 may be separated from the member 81 and flange 230 by rollers (240, 242), Figs. 29 and 31 (not shown).