MAGNETIC DAMPER FOR DRIVE GAS CHECK VALVE OF ANESTHESIA VENTILATOR
Publication Date: 2014-May-27
The IP.com Prior Art Database
The invention proposes a magnetic damping apparatus for the drive gas check valve used in single valve controlled anesthesia ventilator. The apparatus includes a magnetic damper design to replace air dashpot in drive gas check valve. The magnetic damper design includes a permanent magnet 10, a coil holder 11 with its bearings 15 and copper coil or ring 12. The magnet 10 is installed in check valve housing and silicon rubber seal 14 is attached under the coil holder 15 to provide check valve function.
FIELD OF INVENTION
The present invention relates generally to a magnetic damper and more particularly to the magnetic damper for drive gas check valve of anesthesia ventilator.
BACKGROUND OF THE INVENTION
In general, absence or malfunction of a damper results in oscillation of patient airway pressure or exhalation difficulties. Generally, parts used for ventilation are of high cost and the availability is low. A precise fabrication is required in the manufacturing process.
A conventional technique includes an air dashpot to control flutter. FIG. 1 depicts an air dashpot used in conventional technique design.
As depicted in the above figure, sliding surface between the weight and the glass bore is precisely fabricated to allow smooth movement while maintaining low leakage. The piston moving in the glass bore is made of black lead to enable self lubricant. The air column above the weight has a precision aperture to control exit flow of gas from this cavity to act as a damper.
Such air dashpot described above is utilized by a drive gas check valve (DCGV), which is a critical part in a single-valve-controlled anesthesia ventilator. The DGCV is a mechanically weighted pop off valve used to control both the flow to the bellows assembly. Collaborated with the flow control valve, the DGCV drives bellows and pressure between the drive gas side and the pilot pressure for the exhalation valve within the vent engine manifold. The DGCV mechanically ensures that the pilot pressure on the exhalation valve is higher than the drive gas pressure. Also, exhalation valve observes pressure and seat prior to the application of drive pressure through the bellows. The soft seat of the DGCV is attached to a weight which slides vertically within a smooth glass bore. The weighted assembly is designed to unseat when the manifold pressure reaches a definite pressure. With the DGCV open, drive gas is allowed to flow to the bellows assembly to push the bellows down and begin delivering a breath. The second function of the valve is to provide a method of damping of the transient flow spikes as the valve opens and closes and responds to the turbulence of drive gas flow.
However, the conventional technique do not provide zero friction, sensitive and high reliable damping feature for anesthesia ventilator.
Therefore there is a need in the art to provide a technique to provide damping feature for anesthesia ventilator.
BRIEF DESCRIPTION OF THE INVENTION
The invention proposes a magnetic damping apparatus for drive gas check valve used in single valve controlled anesthesia ventilator. The proposed apparatus provides zero friction, super sensitive, precisely controlled and highly reliable damping feature for the drive gas check valve, which is a key for the performance and reliability of anesthesia ventilator.
DETAILED DESCRIPTION OF THE INVENTION
The invention proposes a magnetic damping apparatus for drive...