Apparatus for converting a pump to a controller

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
• a stiffener disposed in communication with the diaphragm for transferring the constraint of the diaphragm as a force into the pump, the stiffener including a flat portion disposed against the diaphragm in flush relationship with the diaphragm.

In combination for use with a disposable unit to control the pressure of a fluid flowing from a source to a patient, the disposable unit having a resilient member constrainable in accordance with forces imposed upon the resilient member,

• means for pumping the fluid,
• means disposed in the pumping means for releasably holding the disposable unit for obtaining the flow of fluid from the source to the patient through the disposable unit,
• means disposed on the pumping means and adjustable to provide a first force against the resilient member in a first direction corresponding to a maximum pressure in the fluid flowing from the source to the patient,
• means responsive in the pump to the pressure of the fluid in the disposable unit for producing a second force against the resilient member, in a second direction opposite to the first direction, corresponding to such pressure, and
• means responsive to the difference between the first and second forces on the resilient member for indicating when the pressure of the fluid in the disposable unit exceeds such maximum pressure.

In combination for use with a disposable unit to control the pressure of a fluid flowing from a source to a patient, the disposable unit including a resilient member constrainable in accordance with forces imposed upon the resilient member,

• a casing,
• means in the casing for receiving the disposable unit to obtain a flow of fluid from the source to the patient,
• an adjustable knob supported by the casing to control the maximum pressure of the fluid in the disposable unit in accordance with such adjustment,
• means disposed within the casing and biasing against the resilient member in a first direction by the adjustable positioning of the knob,
• means disposed within the casing and responsive to the fluid flowing from the source to the patient for producing, against the resilient member in a second direction opposite to the first direction, a force dependent upon the pressure of the fluid in the disposable unit, and
• means disposed in the casing and operative to provide an output indication after the bias of the biasing means against the resilient member in the first direction has been overcome by the force on the resilient member in the second direction.

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 having a chamber,
• 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 the 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,
• force-transmitting means disposed in a co-operative relationship with the reinforcement and extending through the opening to produce a force in the pump in accordance with the constraint of the diaphragm,
• the force-transmitting means constituting a stiffener disposed in co-operative relationship with the reinforcement,
• there being a passage in the housing in communication with the opening and the passage being provided with narrower dimensions than the opening, and
• the stiffener having a tubular portion extending through the passage to transmit the force on the diaphragm and having a flat portion integral with the tubular portion and disposed in flush relationship with the resilient 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 for 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 co-operate 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,
• means disposed in the pump for producing a force on the diaphragm in a direction opposite to the constraint produced on the diaphragm in accordance with the pressure of the fluid in the chamber, and
• means disposed in the pump and responsive to the resultant constraint of the diaphragm from the forces in the opposite directions for providing an output indication when the pressure of the fluid in the chamber produces a force on the diaphragm greater than the force produced to oppose the force produced by the fluid in the chamber.

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,
• 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,
• the indicating means including a member coupled to the diaphragm, and
• means responsive to the adjustable setting of the particular limits for imposing a force on the member in a direction opposite to the force imposed upon the member by the constraint of the diaphragm the force having a magnitude dependent upon such adjustable setting.

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 from the pump casing and adjustable in position to control within particular limits the pressure of the fluid within the housing,
• means responsive to the setting of the knob for imposing on the resilient means a constraint in a direction opposite to the constraint imposed upon the diaphragm by the fluid passing through the housing, and
• means operatively coupled to the resilient means and the knob for providing an output indication when the resilient means have received from the fluid in the housing a particular constraint exceeding the constraint imposed in the opposite direction in accordance with the setting of the knob.