Source: http://www.google.com/patents/US7464591?dq=6,455,937
Timestamp: 2016-06-25 14:44:41
Document Index: 614230960

Matched Legal Cases: ['art 2', 'art 3', 'arts 4', 'arts 6', 'art 3', 'art 7', 'art 6']

Patent US7464591 - Semiconductor acceleration sensor - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inPatentsA semiconductor acceleration sensor having beam parts formed in substantially L-shape to surround a weight part, wherein formed to surround a square part, as seen in plan view and constituting the weight part, are two elongated L-shaped beam parts, at locations close to proximal end portions of which...http://www.google.com/patents/US7464591?utm_source=gb-gplus-sharePatent US7464591 - Semiconductor acceleration sensorAdvanced Patent SearchPublication numberUS7464591 B2Publication typeGrantApplication numberUS 11/579,178PCT numberPCT/JP2006/000819Publication dateDec 16, 2008Filing dateJan 20, 2006Priority dateFeb 1, 2005Fee statusPaidAlso published asCN1942768A, CN100554970C, EP1750132A1, EP1750132A4, US20080022770, WO2006082716A1Publication number11579178, 579178, PCT/2006/819, PCT/JP/2006/000819, PCT/JP/2006/00819, PCT/JP/6/000819, PCT/JP/6/00819, PCT/JP2006/000819, PCT/JP2006/00819, PCT/JP2006000819, PCT/JP200600819, PCT/JP6/000819, PCT/JP6/00819, PCT/JP6000819, PCT/JP600819, US 7464591 B2, US 7464591B2, US-B2-7464591, US7464591 B2, US7464591B2InventorsYoshihisa Fukuda, Kouji Sakai, Atsushi Ishigami, Eiichi Furukubo, Ryosuke Meshii, Takashi YajimaOriginal AssigneePanasonic Electric Works Co., Ltd.Export CitationBiBTeX, EndNote, RefManPatent Citations (11), Non-Patent Citations (7), Referenced by (9), Classifications (7), Legal Events (4) External Links: USPTO, USPTO Assignment, EspacenetSemiconductor acceleration sensor
US 7464591 B2Abstract
A semiconductor acceleration sensor having beam parts formed in substantially L-shape to surround a weight part, wherein formed to surround a square part, as seen in plan view and constituting the weight part, are two elongated L-shaped beam parts, at locations close to proximal end portions of which are formed protruding portions protruding from a fixed part toward the weight part, and receiving recessed portions protruding from the weight part toward the fixed part to surround the protruding portions. The protruding portions have an outer shape substantially the same as an inner wall surface of the receiving recessed portions so that movements of the weight part in any directions in a horizontal direction perpendicular to an up and down direction are limited as a result of reception of the protruding portions by the receiving recessed portions. Thus, even when a side impact is applied to the acceleration sensor, the weight part is prevented from moving significantly, thereby preventing an excessive stress from being applied to the beam parts to break the beam parts.
The present invention relates to a semiconductor acceleration sensor, and more particularly to a semiconductor acceleration sensor which has a weight part connected by elongated beam parts to a fixed part, and which, with an applied acceleration, detects the acceleration by using a movement of the weight part in the direction of the acceleration caused by bending of the beam parts.
A semiconductor acceleration sensor is conventionally known to detect an acceleration based on a movement of a weight part relative to a fixed part when the acceleration is applied thereto. This acceleration sensor has a weight part which is a movable part provided on an end of a cantilever-like bending portion (thin beam part) extending from the fixed part, and has such a structure that causes the bending portion to bend and the weight part to move when an acceleration is applied thereto, and that electrically detects the change. As described in Japanese Laid-open Patent Publication 2000-338124 and Japanese Laid-open Patent Publication Hei 7-159432, examples of the type for electrically detecting movement of the weight part include, for example: acceleration sensors that form a gauge resistor on a bending portion connecting the weight part, and measure a change in a resistance value of the gauge resistor so as to detect a bending of the bending portion; and those that form the weight part itself into an electrode, and detect a change in electrostatic capacity caused by movement of the weight part to change the distance from a fixed electrode part.
Thus, an object of the present invention is to provide a semiconductor acceleration sensor that limits a movement range of a weight part in a horizontal direction perpendicular to an up and down direction which is a primary direction to detect an acceleration of the weight part in a semiconductor acceleration sensor having the above-described structure, and that prevents an excessive stress from being applied to beam parts connecting a fixed part to a weight part even when a side impact in any direction is applied, preventing the beam parts from breaking.
FIG. 1( a) is a top plan view of a semiconductor acceleration sensor according to a first embodiment of the present invention, while FIG. 1( b) is a top plan view of a silicon substrate portion of the sensor;
BEST MODE FOR CARRAYING OUT THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. First, referring to FIG. 1 and FIG. 2, the entire structure of a semiconductor acceleration sensor according to the present embodiment will be described. The acceleration sensor 1 of the present embodiment comprises a silicon substrate 5 having a fixed part 2, a weight part 3 and beam parts 4 formed therein as well as glass parts 6, 7 sandwiching the silicon substrate 5 from the top and bottom, in which a space for the weight part 3 to move up and down is formed by a recessed portion 7 a formed in the lower glass part 7 and a recessed portion 5 a formed in an upper surface of the silicon substrate 5 (FIG. 2). A fixed electrode 8 using a conductive thin film is formed on a lower surface of the upper glass part 6. A voltage is applied to this fixed electrode 8 via a conductive lead metal film 11 which passes through a through-hole 9.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS5284057 *Nov 13, 1992Feb 8, 1994Delco Electronics CorporationMicroaccelerometer having low stress bonds and means for preventing excessive Z-axis deflectionUS5351542 *Jan 27, 1992Oct 4, 1994Kansei CorporationAcceleration sensor assemblyUS5490421 *Jan 23, 1995Feb 13, 1996Fuji Electric Co., Ltd.Semi-conductor acceleration sensor having thin beam supported weightUS6392220 *Sep 2, 1999May 21, 2002Xros, Inc.Micromachined members coupled for relative rotation by hingesUS20060053908Aug 26, 2004Mar 16, 2006Atsushi IshigamiSensor deviceJP2000338124A Title not availableJP2000346866A Title not availableJP2002055117A Title not availableJPH07159432A Title not availableJPH08240609A Title not availableJPH11337570A Title not available* Cited by examinerNon-Patent CitationsReference1English Language Abstract of JP 11-337570.2English Language Abstract of JP 2000-338124.3English Language Abstract of JP 2000-346866.4English Language Abstract of JP 2002-055117.5English Language Abstract of JP 7-159432.6English Language Abstract of JP 8-240609.7U.S. Appl. No. 10/599,396 to Meshii et al., filed Sep. 27, 2006.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS7905146 *Mar 15, 2011Oki Semiconductor Co., Ltd.Inertial sensorUS8459116Jun 11, 2013Alps Electric Co., Ltd.Physical quantity sensorUS8516891 *Jan 16, 2008Aug 27, 2013Analog Devices, Inc.Multi-stage stopper system for MEMS devicesUS8850889Nov 19, 2009Oct 7, 2014Panasonic CorporationAcceleration sensorUS20080196497 *Jan 23, 2008Aug 21, 2008Oki Electric Industry Co., Ltd.Inertial sensorUS20110138914 *Nov 19, 2009Jun 16, 2011Panasonic Electric Works Co., Ltd.Acceleration sensorUS20120228725 *Sep 13, 2012Analog Devices, Inc.Multi-Stage Stopper System for MEMS DevicesUS20130019678 *Jul 22, 2011Jan 24, 2013Lazaroff Dennis MLimiting travel of proof mass within frame of MEMS deviceUS20130111992 *Nov 9, 2012May 9, 2013Robert Bosch GmbhProof mass positioning features having tangential contact surfaces* Cited by examinerClassifications U.S. Classification73/514.36, 73/514.38International ClassificationG01P15/00, G01P15/02Cooperative ClassificationG01P2015/0871, G01P15/08European ClassificationG01P15/08Legal EventsDateCodeEventDescriptionOct 30, 2006ASAssignmentOwner name: MATSUSHITA ELECTRIC WORKS, LTD., JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FUKUDA, YOSHIHISA;SAKAI, KOUJI;ISHIGAMI, ATSUSHI;AND OTHERS;REEL/FRAME:018512/0392;SIGNING DATES FROM 20061011 TO 20061017May 16, 2012FPAYFee paymentYear of fee payment: 4Feb 8, 2016ASAssignmentOwner name: PANASONIC CORPORATION, JAPANFree format text: MERGER AND CHANGE OF NAME;ASSIGNORS:PANASONIC ELECTRIC WORKS CO., LTD.;PANASONIC CORPORATION;REEL/FRAME:037680/0794Effective date: 20120101Jun 2, 2016FPAYFee paymentYear of fee payment: 8RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services