Apparatus for converting a pump to a controller

In combination for use with a pump for introducing fluid at controlled pressures to a receiver and for providing an output indication when the pressure of the fluid exceeds a particular value, the pump having detent means,

• conduit means extending from the pump to the receiver to introduce fluid from the pump to the receiver,
• resilient means included in the conduit means for variable positioning in accordance with variations in the pressure of the fluid in the conduit means,
• actuatable means operatively coupled to the resilient means for movement with the resilient means to obtain the production of the output indication when the resilient means has reached a particular position, and
• detent means disposed externally of the conduit means for co-operating with the detent means on the pump to hold the circuit means in a particular fixed relationship to the pump.

The combination for controlling the flow of fluid to a receiver,

• a pump,
• conduit means extending from the pump to the receiver to introduce fluid from the pump to the receiver,
• resilient means included in the conduit means for variable positioning in accordance with variations in the pressure of the fluid in the conduit means,
• actuatable means included in the conduit means and operatively coupled to the resilient means for movements with the resilient means to obtain the production of the output indication when the resilient means has reached a particular position,
• sensing means associated with the actuatable means for sensing when the actuatable means has moved through a particular distance, and
• detent means disposed in cooperative relationship on the pump and the conduit means for retaining the conduit means in a particular fixed, but removable, relationship to the pump.

In combination for controlling the flow of fluid to a receiver,

• a pump for pumping fluid to the receiver,
• conduit means for receiving the fluid from the pump and for introducing the fluid to the receiver,
• first means associated with the conduit means and responsive to variations in the pressure of the fluid in the conduit means for variable positioning in accordance with such variations in fluid pressure, and
• second means responsive to variations in the positioning of the first means for producing a signal for discontinuing the operation of the pump when the first means has been displaced through a particular distance,
• the conduit means and the first means being disposed in a cassette and first detent means being provided in the pump and second detent means being provided in the cassette for cooperation with the detent means on the pump to provide a releasable coupling between the cassette and the pump,
• the conduit means including a housing and inlet and outlet lines,
• the first means including a chamber between the inlet and outlet lines, and
• means disposed in the chamber and responsive to the pressure of the fluid in the chamber for variable positioning in accordance with such variations in fluid pressure,
• the second detent means being disposed on the housing and the first detent means include spring arms on the pump for releasably holding the second detent means.

A method of controlling the pressure of a fluid being pumped from a source to a patient, including the following steps:

• providing a pump for pumping the fluid from the source to the patient and operatively coupling the pump between the source and the patient,
• passing the pumped fluid through a cassette containing a resilient diaphragm constrainable in accordance with the pressure of the fluid passing through the cassette,
• converting the constraint of the resilient diaphragm to a movement of an output member,
• providing a member adjustable in positioning and cooperative with the output member to provide an output signal at a position of the output member dependent upon the adjustment in the positioning of the adjustable member, and
• interrupting the operation of the pump upon the production of the output signal to maintain within particular limits the pressure introduced to the patient,
• the constrainable diaphragm in the cassette being coupled to a constrainable diaphragm in the pump to produce a constraint of the constrainable diaphragm in the pump in accordance with the constraint of the diaphragm in the cassette and the output member being disposed in the pump and being movable in accordance with the constraint of the diaphragm in the pump and the adjustable member being disposed in the pump.

In combination for converting a pump into a controller for controlling within particular limits the pressure of fluid introduced from a source to a patient,

• a housing having an inlet and an outlet for the flow of fluid and having a chamber in communication with the inlet and the outlet,
• a resilient diaphragm disposed in the chamber and constrainable in accordance with the pressure of the fluid in the chamber,
• a pivotable member,
• a light source,
• a photocell,
• means for providing for a variation in the amount of the light passing from the light source to the photocell in accordance with the variations in the positioning of the resilient member, and
• means responsive to a particular change in the passage of the light from the source to the photocell for indicating that the pressure of the fluid within the housing has exceeded the particular limits.

In combination for converting a pump into a controller for controlling within particular limits the pressure of fluid introduced from a source to a patient,

• a housing,
• detent means on the housing for releasable attachment to the pump,
• an inlet into the housing for receiving the fluid,
• an outlet from the housing for providing for the transfer of the fluid from the housing,
• a chamber within the housing in communication within the inlet and the outlet,
• a diaphragm disposed across the chamber for constraint in accordance with the pressure of the fluid in the chamber, and
• an arm disposed in communication with the diaphragm for transferring the constraint of the diaphragm as a force into the pump.

In combination in a disposable unit for operating in conjunction with a pump to control within particular limits the pressure of fluid introduced from a source to a patient,

• a housing,
• detent means on the housing,
• an inlet for receiving the fluid from the source,
• an outlet for passing the fluid to the patient,
• a resilient diaphragm disposed across the chamber to close the chamber and to become constrained in accordance with the pressure of fluid in the chamber,
• a reinforcement on the diaphragm at an intermediate position on the diaphragm,
• an opening disposed in the housing in communication with the reinforcement at the end of the housing opposite the chamber, and
• force-transmitting means disposed in cooperative relationship with the reinforcement and extending through the opening to produce a force in the pump in accordance with the constraint of the diaphragm.

In combination for controlling the pressure of fluid passing from a source to a patient,

• a pump for pumping fluid from the source to the patient,
• a casing supported by the pump,
• there being a socket in the casing,
• detent means in the socket,
• a disposable unit including a housing dimensioned to fit into the socket and including detent means disposed on the housing to cooperate with the detent means in the socket for removably retaining the disposable unit in the socket,
• there being a chamber in the housing,
• an inlet disposed in the housing and communicating with the chamber to provide for the introduction of fluid from the source into the chamber,
• an outlet disposed in the housing and communicating with the chamber to provide for the passage of fluid from the chamber to the patient,
• a resilient diaphragm disposed in the chamber to close the chamber and constrainable in accordance with the pressure of the fluid in the chamber, and
• means disposed in the pump and responsive to the constraint of the diaphragm for providing an output indication when the pressure of the fluid in the chamber has reached a particular limit.

In combination for controlling within particular limits the pressure of fluid introduced from a source to a patient,

• a pump for pumping the fluid from the source at a positive pressure,
• a housing having an inlet and an outlet for the flow of fluid and having a chamber in communication with the inlet and the outlet,
• a resilient diaphragm disposed in the chamber and constrainable in accordance with the pressure of the fluid in the chamber,
• means for removably supporting the housing on the pump,
• means disposed on the pump for adjustably setting the particular limits for the pressure of the fluid flowing through the chamber, and
• means responsive to the constraint of the diaphragm and the adjustable setting of the particular limits for providing an output indication when the pressure of the fluid in the chamber has reached such particular limits.

In combination for converting a pump into a controller for controlling within particular limits the pressure of fluid introduced from a source to a patient,

• a pump for directing fluid from the source under pressure, the pump including a casing having a receptacle,
• a housing removably disposed within the casing for receiving the fluid directed from the source by the pump and for directing the fluid to the patient,
• resilient means included within the housing for constraint in accordance with the pressure of the fluid in the housing.
• a knob extending externally from the pump casing and adjustable in position from a position external to the pump casing to control within particular limits the pressure of the fluid within the housing, and
• means operatively coupled to the resilient means and the knob for providing an output indication when the resilient means have received a particular constraint dependent upon the setting of the adjustable knob.