Patent ID: 6789540
Filing Date: 2004-09-14
Classification: A61M

Abstract:
A respirator comprising:a hollow body having a closed end and an assembly end and defining therein a fresh air chamber and an exhaust air chamber, wherein the fresh air chamber has a fresh air inlet formed close to a first end inside the fresh air chamber to communicate the fresh air chamber with surrounding air and provided with a first unidirectional valve to allow air from the surrounding air to flow only into the fresh air chamber and a first breathing pipe formed close to a second end inside the fresh air chamber to communicate the fresh air chamber with the surrounding air, the exhaust air chamber has an exhaust pipe formed close to a first end inside the exhaust air chamber to communicate the exhaust air chamber with surrounding air and provided with a second unidirectional valve to allow air from the exhaust air chamber to flow only out of the exhaust air chamber and a second breathing pipe formed close to a second end inside the exhaust air chamber to communicate the exhaust air chamber with the surrounding air; a mask having an air inlet pipe communicating the interior of the fresh air chamber with the mask and provided with a third unidirectional valve to allow the air from the fresh air chamber to flow only to the mask and an exhaust air pipe communicating the interior of the exhaust air chamber with the mask and provided with a fourth unidirectional valve to allow air from the mask to flow only to the exhaust air; a piston mechanism having a first piston reciprocally received in the fresh air chamber to intermittently force the air inside the fresh air chamber to the mask via the air inlet pipe and a second piston reciprocally received in the exhaust air chamber to intermittently force the air inside the exhaust air chamber out to surroundings; a handle operably connected to the first piston and the second piston; and means for driving the handle to move linearly so as to drive the first piston and the second piston to move simultaneously inside the fresh air chamber and the exhaust air chamber respectively.