GB1172828A - Improvements in and relating to Rotary Positive-Displacement Internal Combustion Engines. - Google Patents

Abstract

1,172, 828. Rotary positive-displacement I. C. engines. SVENSKA ROTOR MASKINER A. B. Nov.28, 1966 [Dec. 6, 1965; May 9, 1966], Nos. 51573/ 65 and 20447/ 66. Heading F1F. A rotary positive-displacement I. C. engine includes primary and secondary rotors 40, 46, Fig. 2, that have axially-straight teeth or lands 48, 62 and are lodged within two parallel intersecting bores in a casing 20, the profiles of said teeth being dissimilar and such that the intermeshing teeth define a sealed chamber wherein fuel combustion occurs when initiated by a spark plug 100. In operation, atmospheric air enters spaces or grooves 50, 64 between adjacent teeth on said rotors through channels 32, 34 in an end wall of the casing 20, compression of said air being effected in a space or chamber between the rotors that is formed when the spaces 50, 64 join each other across a line of intersection 28 between the parallel bores. At the end of the compression phase, fuel is injected into the second said chamber through a nozzle 98 before the chamber is closed by a tooth 62 abutting the corresponding tooth 48 to form the first said chamber. When the products of combustion in the first said chamber have undergone expansion, they are conveyed in the associated spaces 50, 64 to channels 36, 38 in the other end wall of the casing. The channels 36, 38 in one end wall overlap the channels 32, 34 in the other end wall, as shown, so that fresh air enters the spaces 50, 64 while they are still in register with the channels 36, 38 and ejects residual exhaust-gases, the said spaces being subsequently cut-off from the channels 32 - - 38 simultaneously. The exhaust-gases leaving the channels 36, 38 may pass through a turbine (128, Fig. 5, not shown), which drives a blower (130) for supplying air to the channels 32, 34. Alternatively, air may be supplied to the channels 32, 34 by either a fan (not shown) that is driven by the power-output shaft 102, Fig. 1, which is coupled to the rotor 40, or an exhaust-gas actuated injector (not shown). Cooling of each of the rotors is effected by fluid e.g. oil, supplied to a chamber 116 and passages 120 therein through a pipe 114 engaging with a stationary nozzle 110, hot fluid being discharged from the passages 120 through an annular passage 122, a chamber 124 and a passage 126. Cooling of the casing 20 is effected by fluid e. g. water, flowing through channels 104 therein from an inlet 106 to an outlet 108. The rotors are synchronously coupled to each other by a train of spur gears (90, 92, 94, 96, Fig. 3, not shown). A second embodiment Figs. 6 to 8 (not shown), differs from that shown mainly in that the casing contains a plate (134) constituting a valve member whose angular position can be changed by a gear (142) so as to virtually modify the location of the channel 36 relative to the channel 32 and consequently the performance of the engine. The plate (134) contains an arcuate port (138) whose profile is similar to that of the channel 36, the latter being overlapped by the said port and in communication with a radial recess (144) in the wall of the bore containing the primary rotor 40. A similar recess (146) in the wall of the other bore containing the secondary rotor 46 communicates with the channel 38. This embodiment also differs in that bevel gearing (148, 154, 158, 164) is provided to couple the rotors to each other. In a third embodiment, Fig. 9 (not shown), the valve member is constituted by a plate (176) containing a channel (184) for cooling fluid e.g. water, which channel is connected to a source of such fluid by a flexible tube (186) to permit angular displacement of the plate. In a fourth embodiment, Figs. 10 and 11, fuelair mixture generated by a carburetter 192 enters the engine through channels 194, 196, air for scavenging purposes being directed into the appropriate spaces between the teeth of the two rotors through separate channels 188, 190 that are overlapped by the channels 36, 38. Any scavenging air remaining in said spaces is driven through channels 198, 200 into the carburetter by a fan 202. This embodiment is otherwise similar to that according to Figs. 1 and 2.