CN-114867995-B - Flow measuring device

Abstract

The invention provides a flow rate measuring device capable of suppressing inclination of a chip package relative to a circuit board and reducing deviation of flow rate detection accuracy. The flow rate measurement device (20) is characterized by comprising a chip package (310) which is provided with a flow rate sensor (311) and is formed with a passage wall (314), and a circuit board (300) on which the chip package (310) is mounted, wherein the chip package (310) is arranged such that the flow rate sensor (311) is opposed to a part of the circuit board (300), and a part of the passage wall (314) which is a resin part of the chip package (310) is mounted in contact with the circuit board (300).

Inventors

• YOGO TAKAYUKI
• Fadin fahana bintiharidan
• UENODAN AKIRA
• ABE HIROYUKI
• Ijuin Mizuho

Assignees

• 日立安斯泰莫株式会社

Dates

Publication Date

20260508

Application Date

20201020

Priority Date

20191114

Claims (3)

1. 1. A flow rate measurement device is characterized by comprising: A resin package having a flow rate detecting element and formed with a passage wall, and A circuit substrate on which the resin package is mounted, The resin package is configured such that the flow rate detecting element is opposed to a part of the circuit substrate, A part of the resin portion of the resin package is mounted in contact with the circuit substrate, The flow sensing element has a membrane that, The resin package has a lead frame for mounting the flow rate detecting element, Sealing the flow rate detecting element with a resin so as to expose the diaphragm, A portion of the via wall is in contact with the circuit substrate, The flow rate measuring device has a sub-passage for taking in a part of the gas to be measured flowing through the main passage, and a circuit chamber adjacent to the sub-passage and accommodating the circuit board, The circuit board has a protruding portion protruding from the circuit chamber toward the sub-path, The resin package is mounted on the circuit board, and the flow rate detection element is disposed so as to face the protruding portion of the circuit board.
2. 2. A flow rate measuring apparatus according to claim 1, wherein, The resin package has a base end portion disposed in the circuit chamber and a tip end portion disposed in the sub-passage, The base end portion is provided with a connection terminal connected to the circuit board, and the tip end portion is provided with the flow rate detection element.
3. 3. A flow rate measuring device according to claim 2, wherein, The resin package has a groove extending along the sub-path on a surface of the distal end portion facing the circuit board, and the flow rate detection element is exposed in the groove.

Description

Flow measuring device Technical Field The present invention relates to a flow rate measurement device for measuring a flow rate of a gas to be measured. Background Patent document 1 describes a physical quantity measuring device for detecting a physical quantity of a gas to be measured flowing in a main passage, the physical quantity measuring device including a flow sensor for detecting a flow rate of the gas to be measured, an LSI for driving the flow sensor, a chip package formed by sealing the flow sensor and a lead frame for supporting the LSI with a resin, and a circuit board on which the chip package is mounted, the chip package being fixed to the circuit board in a state in which a part including the flow sensor protrudes laterally from an end of the circuit board. Prior art literature Patent literature Patent document 1 wo2019/064887 Disclosure of Invention Problems to be solved by the invention The flow rate measurement device of patent document 1 has a structure in which a connection terminal provided at a base end portion of a chip package is fixed to a substrate by soldering, a groove formed at a tip end portion of the chip package is arranged so as to face the substrate, and a flow rate of a gas to be measured flowing through a passage formed by the substrate and the groove is detected by a flow rate sensor provided in the groove. Since the chip package has a structure in which the cantilever is supported by the substrate by solder fixation, the posture of the chip package at the time of solder fixation is liable to become unstable. Therefore, when the chip package is soldered to the substrate in a posture inclined from the reference, the size of the via may vary, and there is a possibility that the flow rate detection accuracy of each individual body may vary. The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a flow rate measurement device capable of suppressing tilting of a chip package with respect to a substrate and reducing variation in flow rate detection accuracy. Means for solving the problems The flow rate measuring device according to the present invention for solving the above-described problems is characterized by comprising a resin package having a flow rate detecting element and formed with a passage wall, and a substrate on which the resin package is mounted, wherein the resin package is disposed such that the flow rate detecting element faces a part of the circuit substrate, and a part of a resin portion of the resin package is mounted in contact with the circuit substrate. Effects of the invention According to the present invention, the inclination of the chip package with respect to the substrate can be suppressed, and the variation in the flow rate detection accuracy can be reduced. Other features relevant to the invention will be apparent from the description and drawings of the specification. The problems, structures, and effects other than those described above will be apparent from the following description of the embodiments. Drawings Fig. 1 is a system diagram showing an embodiment of a flow rate measurement device according to the present invention used in an internal combustion engine control system. Fig. 2 is a front view of the flow rate measurement device according to the first embodiment. Fig. 3 is a front view of a circuit substrate on which the chip package in the first embodiment is mounted. Fig. 4 is a schematic view in a cross-section of line A-A of fig. 3. Fig. 5 is a diagram illustrating another modification, and corresponds to fig. 4. Fig. 6 is a diagram illustrating another modification, and corresponds to fig. 4. Fig. 7 is a diagram illustrating another modification, and corresponds to fig. 4. Fig. 8 is a rear view of the chip package in the first embodiment. Fig. 9 is a diagram illustrating another modification, and corresponds to fig. 8. Fig. 10 is a diagram illustrating another modification, and corresponds to fig. 8. Fig. 11 is a diagram illustrating another modification, and corresponds to fig. 8. Fig. 12 is a front view of a circuit board on which the chip package according to the second embodiment is mounted, and corresponds to fig. 3. Fig. 13 is a diagram illustrating a comparative example. Detailed Description The embodiments described below for carrying out the present invention solve various problems that are desired to be solved as actual products, and in particular, various problems that are desired to be solved for use as a detection device for detecting a physical quantity of intake air of a vehicle, and various effects are exhibited. One of the various problems to be solved by the following embodiments is the content described in the problem section to be solved by the invention, and one of the various effects to be achieved by the following embodiments is the effect described in the effect section. Various problems to be solved by the following embodiments a