Peristaltic pump assembly

The present disclosure relates generally to peristaltic pumps and, more particularly, to a peristaltic pump assembly.

Rotary-style peristaltic infusion pumps are often used to deliver fluid in a very controlled manner such as, for example, the intravenous delivery of medicine to a patient. These peristaltic pumps typically include a disposable pumping cassette and an assembly of radially arranged rollers received within a cavity of the cassette, wherein the rollers revolve together when rotationally driven by a drive shaft operated by a pump motor. A flexible tubing is disposed around a portion of the assembly of rollers and generally exerts a force against the rollers in contact therewith to thereby hold the rollers against the drive shaft.

In response to rotational movement of the rollers, portions of the flexible tube that are in contact with the rollers compress or otherwise occlude against a wall of the cassette. As a result, fluid traveling through the tube is temporarily trapped in the tube between the occluded points. The trapped fluid is released from the tube when the occlusion force on the tube is released. In this manner, fluid is urged through the tube via peristaltic wave action.

Sometimes a roller may not directly contact the tubing. In this instance, the roller(s) may undesirably move or shift and lose proper contact with the drive shaft. This could cause errors in various pumping operations, which may diminish the overall performance of the pump.

Disclosed herein is a peristaltic pump assembly including a cassette configured to be operatively engaged with a pump housing. A roller assembly is operatively disposed within a cavity of the cassette and includes a plurality of rollers that may be arranged in a planetary configuration around a drive shaft. At least one guide element is disposed about the periphery of the roller assembly and in engagement with at least a portion of an outer surface of each of the plurality of rollers.

Embodiment(s) of the peristaltic pump assembly as disclosed herein advantageously guide and/or locate a plurality of rollers of a roller assembly in response to rotational movement of a drive shaft to thereby maintain contact of the rollers with the drive shaft. The guide element may also improve the overall performance of the peristaltic pump by, for example, enabling the pump to achieve higher precision in fluid volume delivery. The guide element is also relatively simple to incorporate into the pump assembly.