Abstract: A rotary peristaltic pump arrangement and method, with a set of specially constructed tube set conduits interchangeably interconnectable in selectively responsively sensed and operationally affecting relationship with the pump. The pump is driven by a pulse-actuated stepping motor, and the total quantity of pulses fed to the pump for any selected volume from one of the conduits is controlled by and as a function of which one of the set of plural sizes of tube set conduits is connected to the pump. The control is automatically affected through actuation or nonactuation of at least one switch sensor on the pump by special anchor-connecting flanges on the tube set conduits which interchangeably mate in anchored connection with corresponding anchor-connection slots on the pump and adjacent one which the switch sensor is disposed.

Abstract: A compact, relatively low cost twin piston pump (20) especially adapted for the pumping of foods (e.g. juices, puddings or particulates such as stews and chilies) is provided which includes quick detach yoke and clevis assemblies (108, 124, 110, 126) connecting the reciprocable pistons (100, 102) with their associated hydraulic cylinders (116, 118), thereby permitting quick cleanup of the machine (20). A jacking screw plate (136) is used for forward mounting of the piston and cylinder assemblies (84, 86, 116, 118) coupled with the sleeves (42, 44) and associated pistons (100, 102). This permits precise adjustment of the working components of the machine, while eliminating expensive bearings and heavy duty framing members. The pump (20) is also provided with a slide plate-type valve (38, 184) for controlling output of product from the pump (20). In one valve embodiment (184) a two-part metallic slide plate assembly (192, 200) is sandwiched between a pair of apertured nylon plates (186).

Abstract: A hermetic reciprocating piston refrigeration compressor utilizes separate cylinder head members for the discharge and suction plenum chambers adjacent the discharge and suction valves. The two cylinder heads extend over substantially the entire area of the valve plate at the end of the cylinder carrying the valves. A discharge cylinder head is formed of metal while the suction cylinder head is formed of a plastic material of low thermal conductivity to minimize heat transfer between the discharge and suction plenums. The suction cylinder head is formed as a unitary member to include also passages and a portion of the suction muffler and is secured in place by a single fastening member.

Abstract: A spring-loaded latching mechanism for a peristaltic pump that automatically sets and maintains a desired roller head tension. The spring-loaded latching mechanism includes a pair of counter-rotating latching cams positioned on opposite sides of a pump housing. Each latching cam has an indented or slotted portion for engaging a disposable tubing cassette. The disposable tubing cassette includes a length of flexible tubing supported by a circular race or channel. The latching cams are spring-loaded and, when the disposable tubing cassette is inserted into the pump housing, the latching cams urge the disposable cassette with its length of flexible tubing and circular race against a pump roller head to provide the desired roller head tension.