Pump particularly useful in respirator apparatus and exhalation valve assembly thereof
First Claim
1. Respirator apparatus comprising:
- a pump housing having an inlet at one end, an outlet at the other end, and a cylinder between said inlet and outlet;
a piston reciprocatable axially within said cylinder and dividing its interior into an inlet chamber communicating with said inlet, and an outlet chamber communicating with said outlet;
an exhalation valve coupled to the pump housing outlet via a coupling fitting;
and a one-way valve in said coupling fitting and leading to the atmosphere;
said one-way valve being normally closed, but automatically opening by a negative pressure within said coupling fitting to connect the interior of said coupling fitting to the atmosphere.
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Accused Products
Abstract
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.
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Citations
6 Claims
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1. Respirator apparatus comprising:
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a pump housing having an inlet at one end, an outlet at the other end, and a cylinder between said inlet and outlet; a piston reciprocatable axially within said cylinder and dividing its interior into an inlet chamber communicating with said inlet, and an outlet chamber communicating with said outlet; an exhalation valve coupled to the pump housing outlet via a coupling fitting; and a one-way valve in said coupling fitting and leading to the atmosphere;
said one-way valve being normally closed, but automatically opening by a negative pressure within said coupling fitting to connect the interior of said coupling fitting to the atmosphere. - View Dependent Claims (2, 3, 4, 5, 6)
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Specification