| 摘要 |
PURPOSE:To improve the safety margin, by providing an atmospheric opening hole at a part of cap or on a housing and a check valve therein. CONSTITUTION:A pressure is applied to a silicon diaphragm element 1 through a hole 9 provided on a housing 5 and a hole 8 provided on a support base 2. The element 1 deforms according to the pressure applied and the deformation stress thereon is converted into an electrical signal with a diffusion gauge resistance formed on the surface of the element 1. When the element 1 breaks, not only the electrical signal as pressure sensor becomes abnormal, but also a pressure medium is extruded through the broken part to break through a silicon gel 14 as soft body and flows out of a pressure sensor through an atmospheric opening hole 15. But as a cylinder 11 is provided communicating with the opening hole 15, the pressure medium is allowed to form a flow in a fixed direction in the cylinder 11 so as to press a ball bearing 10 toward the opening hole 15. In this manner, the bearing 10 can close the opening hole 15 to prevent the flowout of a large amount of pressure medium. |
