Peristaltic pump
AssigneeNxStage Medical, Inc.
InventorsJoseph A. Hoell, Jr., Alexander Muller
Life of this patent
Estimating the term…
Abstract
A peristaltic pump actuator includes a rotor element supporting rollers, the rotor element being configured to rotate about a rotor axis and the rollers each being configured to rotate about a roller axis that is parallel to the rotor axis. The rotor element and each of the rollers is constrained such that the rotor element and rollers are able to rotate only about their respective axes. A shoe having a displacement axis perpendicular to the rotor axis is forced against the rollers by an urging element without rotation in any axis. A tube may be placed between the shoe and the rollers.
Claims15
An actuator of a peristaltic pump, comprising:
- a rotor element supporting rollers, the rotor element being configured to rotate about a rotor axis and the rollers each being configured to rotate about a roller axis that is parallel to the rotor axis;
- the rotor element and each of the rollers being constrained such that the rotor element and rollers are able to rotate only about their respective axes;
- and
- a shoe having a displacement axis perpendicular to the rotor axis;
- and
- a linear bearing supporting the shoe, wherein
- the shoe is forced against the rollers by a spring without rotation in any axis,
- the shoe is constrained against all modes of displacement except toward and away from the rotor axis of the rotor element by the linear bearing, and
- the linear bearing includes an outer cylindrical sleeve which holds a pair of polytetrafluoroethylene (PTFE) sleeves spaced apart from each other,
- a supporting shaft passes through the pair of the PTFE sleeves,
- a cavity is defined by an outer surface of the supporting shaft, an inner surface of the outer cylindrical sleeve, and edges of each of the pair of the PTFE sleeves, and
- the cavity is filled with a lubricant.
A method of operating a peristaltic pump, comprising:
- squeezing a tube between at least one actuator roller and a pump shoe by urging the pump shoe toward the at least one actuator roller;
- and
- constraining movement of the at least one actuator roller in one rotating direction and constraining the pump shoe to a single displacement and no rotational directions by a linear bearing that includes an outer cylindrical sleeve which holds a pair of Polytetrafluoroethylene (PTFE) sleeves spaced apart from each other, a supporting shaft passing through the pair of the PTFE sleeves, a cavity being defined by an outer surface of the supporting shaft, an inner surface of the outer cylindrical sleeve, and edges of each of the pair of the PTFE sleeves, and the cavity being filled with a lubricant.
Dependencies are inferred from the claim text.