| 摘要 |
PURPOSE:To take a measurement having no error for a long period without cooling by using a high-temperature resistance type piezoelectric element made of lithium niobate or equal-effect quality as a piezoelectric element, and supporting this piezoelectric element by support means whose quantity of thermal expansion is matched with a case. CONSTITUTION:The piezoelectric element 14 uses the high-temperature resistance type piezoelectric element of lithium niobate or equal-effect quality, and is stored in the case 12. The quantity of thermal expansion of the support means A and A for the piezoelectric element 14 is coincident with that of the case 12. Therefore, the piezoelectric element 14 and a diaphragm 11 maintain invariably constant pressure transmission relaion. Further, the piezoelectric element of lithium niobate or equal-effect quality has a 1,150 deg.C Curie point and neither breaks nor has an error at combustion temperatures below the Curie point. This invention does not requires piping for cooling water for a fuel pressure detector, so a measurement having no error is taken for a long period without cooling. |
