Strain-gauge physical quantity measuring device with an electronic component provided on a flat surface of a cylindrical portion radially distanced from a diaphragm
A device includes: a sensor module; a housing that houses the sensor module; a connector provided to the housing; a terminal provided to the connector; and an elastic electrically conductive member provided in a space between the sensor module and the connector and interposed between the terminal and a pad. The sensor module includes: a ceramic module body including a diaphragm and a cylindrical portion integral with a periphery of the diaphragm; a detector provided on a flat surface of the diaphragm; and the pad and an electronic component provided on a flat surface of the cylindrical portion radially outwardly adjacent to the flat surface of the diaphragm. The pad is electrically connected to the electrically conductive member.
1. A physical quantity measuring device comprising:
a sensor module;
a housing that houses the sensor module;
a connector provided to the housing;
a terminal provided to the connector; and
an elastic electrically conductive member provided in a space between the sensor module and the connector and interposed between the terminal and the sensor module, the sensor module comprising:
a ceramic module body comprising:
a diaphragm displaceable by a pressure of a fluid to be measured introduced into the sensor module; and
a cylindrical portion integral with a periphery of the diaphragm;
a detector comprising a strain gauge provided on a flat surface of the diaphragm opposite to a surface of the diaphragm that is to be in contact with the fluid to be measured, the detector detecting a displacement of the diaphragm;
a pad provided on a flat surface of the cylindrical portion radially outwardly adjacent to the flat surface of the diaphragm, the pad being electrically connected to the detector and being connected to the electrically conductive member; and
an electronic component provided on the flat surface of the cylindrical portion and electrically connected with the detector and the pad, the electronic component being provided opposing the pad across the flat surface of the diaphragm.
2. The physical quantity measuring device according to claim 1 , wherein
the cylindrical portion has an inner circumferential surface defining an attached portion attachable to the housing, and
the attached portion of the cylindrical portion is provided with a step defining a module-side flat surface extending in a radial direction of the cylindrical portion.
3. The physical quantity measuring device according to claim 2 , wherein
the housing comprises a projection having an outer circumferential surface attachable with the attached portion of the cylindrical portion and defining therein an introduction hole through which the fluid to be measured is introduced,
the projection is provided with a housing-side flat surface facing the module-side flat surface, and
an O-ring is provided between the module-side flat surface and the housing-side flat surface.
4. The physical quantity measuring device according to claim 1 , further comprising a temperature measuring element provided on the flat surface of the cylindrical portion.
5. The physical quantity measuring device according to claim 1 , wherein the connector is held in the housing by crimping.
6. The physical quantity measuring device according to claim 1 , wherein
a locking projection is provided to the connector, and
a locking groove engageable with the locking projection is provided to an outer circumferential surface of the sensor module.