초록 ▼

A reciprocating pump particularly useful in ventilator apparatus includes a piston reciprocatable axially within a cylinder and dividing its interior into an inlet chamber and an outlet chamber, a wall fixed within the inlet chamber, and a drive housing fixed to the wall. The drive housing includes

A reciprocating pump particularly useful in ventilator apparatus includes a piston reciprocatable axially within a cylinder and dividing its interior into an inlet chamber and an outlet chamber, a wall fixed within the inlet chamber, and a drive housing fixed to the wall. The drive housing includes a motor, a rotor rotatable by the motor, a nut rotatable within the drive housing, and a screw threadedly coupled at one end to the nut and fixed at its opposite end to the piston. The piston is substantially unrestrained for axial and rotary movement such that forward and reverse rotation of the nut by the motor reciprocates the screw and the piston axially of the cylinder, and also permits the screw and the piston to rotate with respect to the cylinder to thereby even out wear between the piston and cylinder.

대표청구항 ▼

[ What is claimed is:] [1.] An exhalation valve assembly for use with a respiratory pump having an outlet, said assembly comprising:an exhalation valve comprising an inlet port connectable to the outlet of the pump:an outlet port adapted to be connected to a patient, an exhalation port leading to th

[ What is claimed is:] [1.] An exhalation valve assembly for use with a respiratory pump having an outlet, said assembly comprising:an exhalation valve comprising an inlet port connectable to the outlet of the pump:an outlet port adapted to be connected to a patient, an exhalation port leading to the atmosphere, a valve member of the exhalation valve selectively connecting the outlet port to said exhalation port, and a control chamber for controlling the operation of said valve member in response to the pressure in said control chamber; anda control valve for controlling the pressure in said control chamber to increase the pressure therein during inspiration to cause the valve member of the exhalation valve to disconnect the outlet port from said exhalation port, and to decrease the pressure in the control chamber during exhalation to thereby cause the valve member of the exhalation valve to connect the outlet port to the exhalation port of the exhalation valve;wherein said control valve includes:presettable modulating means for presetting a pressure in the control chamber during exhalation to any predetermined partial pressure to thereby preset the exhalation pressure to open said exhalation valve, comprisingan inlet port connectable to an outlet of the pump;a control port connected to said control chamber of the exhalation valve;a vent leading to the atmosphere;a valve member of the control valve movable over a continuum of positions between a first position during inspiration to open a first passageway connecting the control chamber of the exhalation valve to the inlet port of the control valve, and thereby to the outlet port of the pump, and a second position during exhalation to close said first passageway and to open a second passageway connecting the control chamber of the exhalation valve to said vent leading to the atmosphere;a solenoid having an armature controlling the pressure in the control chamber of the exhalation valve according to the energization of the solenoid, and capable of providing any of no, partial or full energization; anda circuit for controlling the energization of said solenoid such that during inspiration it moves said valve member of the control valve fully or partially to said first position, and during exhalation it moves said valve member of the control valve to said second position.