Rotary pump

#The conventional pumps such as centrifugal pumps have a rotary impeller driven by a motor. The blades of the impeller in revolving produce a reduction in pressure at the entrance or eye of the impeller. This causes liquid to flow into the impeller from the suction pipe. This liquid is forced outward along the impeller blades at an increasing velocity. Another kind is a gear pump, which includes two or more impellers in a rotary-pump casing, the impeller will take the form of toothed-gear wheels. As the spaces between the teeth of the impeller pass the suction opening, liquid is impounded between them, carried around the casing to the discharge opening, and then forced out through this opening. These conventional pumps only provide a fixed pump effect, and their pump condition is unchangable.

#The present invention thus relates to an improved pump, more particularly, to a novel rotary pump which may produce two kinds of pump effects and avoid the disadvantages of the prior art.

#An object of the present invention is to apply the main structure of the rotary piston engines to pump to gain a high efficiency implement.

#FIG. 1 is a perspective view of all components of the rotary pump according to the present invention;

#FIG. 2 is a sectional view of the rotary pump according to the present invention;

#FIG. 3 is a front view of the rotary pump in FIG. 2 with the front wall thereof removed;

#As shown in FIGS. 1, 2 and 5, the rotary pump of the present invention mainly comprises a cylinder 30 two fluid channels generally designated 32, a front wall 10, a rear wall 40, a piston 20, a shaft 50, a separating plate 71 and a plunger 70.

#The cylinder 30 has three connected inner walls of hypotrochoid to form a triangular compression or compressing chamber 31. As shown in FIG. 3, two fluid channels 32a and 32b, and generally designated 32 extend into the two inner walls of the cylinder 30. Both ends of each fluid channels 32a, 32b are adjacent to both ends of each inner wall. Moreover, the right ends of the fluid channels 32a, 32b are controlled by check valves 33a, 33b to admit the fluid only which flows from right to left in the channels 32.

#The check valves 24' in the inlet ports 24 of the piston 20 are more clearly shown in FIG. 5 of the drawing, which only lets fluid to flow into compressing chamber 31 from the front section of the piston hole 21 and stops fluid to return back.