Patent ID: 7150444

Claim:
A valve with an integral orifice, the valve comprising: a valve main body made of heat-resisting materials, in which a gas inflow passage and a gas outflow passage in communication with a valve chamber with an open upper end are formed; a valve seat body made of synthetic resin and fitted in the valve chamber of the valve main body and provided with a gas outflow passage in communication with the gas outflow passage of the valve main body and a valve seat; an orifice disc made of heat-resisting materials removably fitted in the gas outflow passage of the valve seat body, and an orifice is formed in the orifice disc and reduces the outflow passage of the valve seat body, wherein the orifice disc is provided at a centre part with a gas outflow passage in communication with the gas outflow passage of the valve seat body, and the orifice disc is accommodated in a concave part formed at a lower portion of the valve seat body, and held between the valve seat body and the valve main body; and an inner disc made of heat-resisting materials, provided with a gas inflow passage and an aperture for receiving the valve seat body, is inserted into the valve chamber of the valve main body, and the valve seat body, fitted in the aperture for receiving the valve seat body, and the orifice disc, accommodated into the concave part of the valve seat body, are fixed airtight to the valve main body by pressing outer circumferential portions of the inner disc from above.