Azbil Corporation

Rina Ogasawara

Yuki Seto

Yoshiyuki Ishikura

Tatsuo Tanaka

Tomohisa Tokuda

Hirofumi Tojo

Masayuki Yoneda

Ayumi Tsushima

Yusuke Niimura

To provide a pressure sensor that has high pressure resistance performance, small measurement error by suppressing hysteresis with respect to pressure, and high sensitivity and high productivity, a pressure sensor includes a diaphragm unit with a first main surface that receives a measurement target fluid's pressure and a second main surface located on the opposite side of this first main surface, a housing, and a sensing unit that outputs the diaphragm unit's deformation as an electric signal, in which at least part of the diaphragm unit has a multi-layer structure in which a plurality of thin plate members are stacked, and the plurality of thin plate members are deformed independently of each other while at least part of the plurality of thin plate members is in press-contact to each other in a pressure receiving state in which the measurement target fluid's pressure is applied to the first main surface.

Pressure sensor with improved measurement accuracy

A pressure sensor () includes a diaphragm (); a semiconductor chip () that includes a plurality of resistors (Rto R) constituting a strain gauge and that has a square shape in plan view; four first structures (to) each having one end joined to a region of the second main surface of the diaphragm that is deformed when a pressure is applied to a first main surface (A) of the diaphragm and having other ends respectively connected to four corners of the semiconductor chip, the first structures extend downward to a second main surface (B); and a second structure () having one end joined to a center () of the diaphragm on the second main surface in plan view and having the other end joined to a center () of the semiconductor chip in plan view, the second structure extending downward to the second main surface.

Pressure sensor

A pressure sensor according to the present invention includes a diaphragm () including a first principal surface (A) and a second principal surface (B) that is opposite thereto, the first principal surface receiving a pressure of a fluid; a semiconductor chip () provided with resistors that constitute a strain gauge; and at least three support members () made of an insulating material, each support member being fixed to the second principal surface at one end thereof and to the semiconductor chip at the other end thereof and extending perpendicularly to the second principal surface so as to support the semiconductor chip. One of the support members () is provided at a center () of the diaphragm in plan view. At least two of the other support members () are provided at positions point-symmetrical about the center of the diaphragm in plan view in a region in which the diaphragm is deformed when a pressure greater than a pressure applied to the second principal surface is applied to the first principal surface.

To suppress variations in the shift amount of the zero point of a sensor output when a pipe is connected to a pressure sensor via a clamp. A pressure sensor includes two semiconductor chips in two straight lines, orthogonal to each other, that pass through a center of a diaphragm in plan view, two resistors in the region between two supporting members supporting one semiconductor chip, and two other resistors in the region between two other supporting members supporting the other semiconductor chip.

A pressure sensor includes a diaphragm having a first principal surface and a second principal surface, a semiconductor chip in which resistors constituting a strain gauge are formed, a first structural body having one end coupled to a center of a second principal surface of the diaphragm and the other end coupled to the other surface of the semiconductor chip, and at least two second structural bodies disposed in two straight lines, orthogonal to each other, that pass through the center of the diaphragm in plan view so as to be disposed separately from the first structural body, and having one ends coupled to the second principal surface and the other ends coupled to the other surface of the semiconductor chip, in which the resistors are formed in regions between the first structural body and the second structural bodies in plan view in the semiconductor chip.

A bottom surface of a sensor chip (or a lower surface of a first retaining member) that introduces the pressure of a measured fluid is joined to a bottom surface of a sensor chamber (or to an inner wall surface of a base body) to allow an enclosing chamber (formed by a pressure receiving chamber and a pressure guiding passage) between a pressure receiving diaphragm and the bottom surface of the sensor chip to communicate with a pressure guiding hole in the first retaining member. The sensor chamber is made open to the atmosphere. Thus, a wire bonding portion of a sensor diaphragm from which wires extend is positioned outside the enclosing chamber, and electrode pins and an enclosed liquid in the enclosing chamber are separated from each other.

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Tokyo, Japan

Rina Ogasawara