Abstract: A hardened powder ring, being a hardened block of talc powder, is inserted into an annular end space between a housing and a sensing element. A pushing member presses and crashes the hardened powder ring into talc powder, thereby stuffing the talc powder into the annular end space. An inner radius rp and an outer radius Rp of the pushing member have the relationship 0.275 mm≦rp−Re≦0.375 mm and 0.15 mm≦rh−Rp≦0.25 mm with respect to an outer radius Re of the sensing element and an inner radius rh of the housing. A press portion of pushing member has an inner curved surface having a curvature radius of 0.3˜0.4 mm and an outer curved surface having a curvature radius of 0.3˜0.5 mm.

Abstract: A hardened powder ring, being a hardened block of talc powder, is inserted into an annular end space between a housing and a sensing element. A pushing member presses and crashes the hardened powder ring into talc powder, thereby stuffing the talc powder into the annular end space. An inner radius rp and an outer radius Rp of the pushing member have the relationship 0.275 mm≦rp−R&thgr;≦0.375 mm and 0.15 mm≦rh−Rp≦0.25 mm with respect to an outer radius R&thgr; of the sensing element and an inner radius rh of the housing. A press portion of pushing member has an inner curved surface having a curvature radius of 0.3˜0.4 mm and an outer curved surface having a curvature radius of 0.3˜0.5 mm.