Pressure detection device with noise resistant pressure sensor

Patent metadata

Field	Value
Publication number	US-11143563-B2
Application number	US-201816487331-A
Country	US
Kind code	B2
Filing date	Jan 30, 2018
Priority date	Feb 24, 2017
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

A noise resistance of a pressure sensor is improved while avoiding a hetero metal bonding. A pressure detection device includes a metal case having the diaphragm which is deformed due to a pressure received from a pressure medium, a sensor element which detects a pressure by detecting the deformation of the diaphragm, a lead frame which is electrically connected to the sensor element, and a connection member which holds the lead frame. A first surface of the lead frame, that is, the surface on a side near the metal case in the parallel plate region, and a second surface of the metal case, that is, the upper surface of the base member interpose at least one of the resin of the connection member being an insulator and the insulating adhesive and are disposed to face each other with a predetermined gap therebetween.

First claim

The invention claimed is:

1. A pressure detection device, comprising:
a metal case which includes a deformation portion, the deformation portion being deformed by a pressure received from a pressure medium;
a detection element which detects the pressure by detecting deformation of the deformation portion;
a lead frame which is electrically connected to the detection element; and
a structure which holds the lead frame,
wherein a first surface of the lead frame and a second surface of the metal case are disposed facing each other with a predetermined gap while interposing an insulator therebetween.

2. The pressure detection device according to claim 1 ,
wherein an electrostatic capacitance between the first surface and the second surface is larger than an electrostatic capacitance between the detection element and the metal case.

3. The pressure detection device according to claim 1 ,
wherein, in the structure, an inserting portion is formed to insert a connector terminal electrically connected to the detection element through the lead frame, and
wherein, in the inserting portion, the lead frame and a pressing member which presses the connector terminal to abut on the lead frame are disposed.

4. The pressure detection device according to claim 3 ,
wherein, in the structure, a guide portion is formed to position the connector terminal when the connector terminal is inserted into the inserting portion.

5. The pressure detection device according to claim 1 ,
wherein the structure is formed of resin, and
wherein part of the structure is disposed between the first surface and the second surface as the insulator.

6. The pressure detection device according to claim 1 ,
wherein the first surface is exposed from a surface of the structure facing the metal case.

7. The pressure detection device according to claim 5 ,
wherein the structure is bonded to the metal case by an adhesive, and
wherein the adhesive is disposed between the first surface and the second surface as the insulator.

8. The pressure detection device according to claim 7 ,
wherein the structure includes a contact surface abutting on the metal case and a filling portion which is recessed from the contact surface and filled with the adhesive.

9. The pressure detection device according to claim 1 ,
wherein the lead frame includes a connection portion which is connected to the detection element by wire bonding, and
wherein an electronic component is connected on an electric path between the connection portion and the first surface.

10. The pressure detection device according to claim 1 ,
wherein the predetermined gap is equal to or more than 0.1 mm.

11. The pressure detection device according to claim 1 ,
wherein the metal case includes a pressure port which guides the pressure medium to the deformation portion, and a base member which is bonded to the structure.

Assignees

• Hitachi Automotive Systems Ltd

Inventors

• Terada Daisuke
• Onuki Hiroshi
• Aoyagi Takuya

Classifications

• G01L19/0061 Primary

  Electrical connection means · CPC title

• G01L19/0084

  to the outside of the housing (other details about the housing see G01L19/14) · CPC title

• G01L19/142

  Multiple part housings · CPC title

• G01L19/069

  Protection against electromagnetic or electrostatic interferences · CPC title

• G01L19/148

  Details about the circuit board integration, e.g. integrated with the diaphragm surface or encapsulation · CPC title