GB1342847A - Squeeze pumps for delivering concrete - Google Patents

Abstract

1342847 Rotary positive-displacement pumps F SCHWING 10 Feb 1972 [11 Feb 1971(2)] 6281/72 Heading F1F A pump for concrete comprises a rubber belt 4 fixed at its ends to a housing 2 defining with the belt a port - cylindrical chamber 14, 15 rollers 5, 6 mounted on a rotor 75 engaging the belt to pump the concrete through the chamber, the rollers being biased towards the belt partly by springs 144, 145, Fig. 10, the remainder of the biasing force being provided by hydraulic piston and cylinder assemblies 134, 136 and 135, 137, which are pressurized as a function of the resistance to delivery of the concrete. The hydraulic pressure supplied to the cylinders is the supply pressure of the motor 109 driving the rotor. The roller carriers 126, 127 have adjustable bearings 158, 159 for engaging pivots 152, 153 on the rotor limiting the outward movement of the carriers, and permitting their retraction for belt removal. The rotor may be stated in either direction, and the springs and cylinders may be located at different distances from the first axes, to provide greater biasing forces in one direction of rotation than in the other Fig. 11 (not shown). The cylinders also may be of different non-sectional areas. The belt is supported on either side by rings (27), 28 running on rollers 30. Reinforcement of the belt is provided by a fabric of steel, textile or plastics mesh and transverse rods, or by a chain with links arranged side-by-side and joined by transverse rods, Figs. 2 to 7 (not shown), the links having curved side portions to permit elastic deformation. The belt has thickened rubber sides to sealingly engage the housing, and is thickened at 65, Fig. 1, to prevent damage by the granular constituents of the concrete on engagement by the rollers. The housing may be filled with a rinsing agent, e.g. water.