Sensor device

• US 20060053908A1
• Filed: 08/26/2004
• Published: 03/16/2006
• Est. Priority Date: 08/26/2003
• Status: Active Grant

• Current Assignee: Mosaid Technologies Incorporated (MOSAID Technologies Inc. (f/k/a Conversant Intellectual Property Management))
• Original Assignee: Asahi Matsushita Electric Works Ltd. (Panasonic Holdings Corporation)
• Inventors: Ishigami, Atsushi, Sakai, Kouji, Meshii, Ryosuke
• Granted Patent: US 7,243,561 B2
• Time in Patent Office: Days
• US Class Current: 73/866.100
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
• CPC Class Codes: G01L 19/0084 to the outside of the housing other details about the housing see G01L19/14
• CPC Class Codes: G01L 19/0092 Pressure sensor associated with other sensors, e.g. for measuring acceleration or temperature G01L9/025, G01L9/045, G01L9/065, G01L9/085, G01L9/105, G01L9/125, G01L19/02, G01L19/04 take precedence; measuring two or more variable G01D21/02; temperature sensors with pressure compensation G01K1/26
• CPC Class Codes: G01L 19/141 Monolithic housings, e.g. molded or one-piece housings
• CPC Class Codes: G01L 19/148 Details about the circuit board integration, e.g. integrated with the diaphragm surface or encapsulation
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/1815 Shape

Abstract

A sensor unit includes a pressure sensor, an acceleration sensor and a signal-processing circuit, which are disposed on the bottom surface of a lead to form a line in the longitudinal direction of the sensor unit. The pressure sensor and the acceleration sensor are disposed at respective symmetrical positions with respect to the center of the signal-processing circuit in the longitudinal direction of the sensor unit. Each of the pressure sensor and the acceleration sensor has substantially the same height dimension. The sensors, the signal-processing circuit and the lead are sealed with a molded body, in such a manner as to allow lead terminals of the lead to protrude outside the molded body. The signal-processing circuit is operable, based on a signal from the acceleration sensor, to control the ON/OFF action of the pressure sensor.

Claims

1. A sensor unit comprising:

a lead having edge portions formed as lead terminals serving as input/output terminals;

a plurality of physical-quantity sensors each disposed relative to said lead and adapted to measure a physical quantity;

a signal-processing circuit disposed relative to said lead and adapted to process a signal from each of said physical-quantity sensors; and

a molded body made of a plastic material, and formed to seal said lead, said physical-quantity sensors and said signal-processing circuit in such a manner as to allow said lead terminals to protrude outside said molded body, wherein

said signal-processing circuit is operable, based on the signal from at least one of said plurality of physical-quantity sensors, to control the ON/OFF action of the remaining physical-quantity sensors.

2. The sensor unit according to claim 1, wherein:

said plurality of physical-quantity sensors include a pressure sensor and an acceleration sensor; and

said molded body is formed with a through-hole extending upward from a pressure-receiving portion of said pressure sensor and having an opening to the outside of said molded body, said through-hole defining a pressure-introducing passage which allows fluid communication between the outside of said molded body and said pressure-receiving portion.

3. The sensor unit according to claim 2, wherein:

said pressure sensor, said acceleration sensor and said signal-processing circuit are disposed to form a line in the longitudinal direction of said sensor unit;

said pressure sensor and said acceleration sensor are disposed at respective symmetrical positions with respect to the center of said signal-processing circuit in the longitudinal direction of said sensor unit; and

each of said pressure sensor and said acceleration sensor has substantially the same height dimension.

4. The sensor unit according to claim 2, further comprising a flexible resin interposed between said acceleration sensor and said molded body.

5. The sensor unit according to claim 2, wherein said pressure-introducing passage includes a plurality of small-diameter channels.

6. The sensor unit according to claim 2, wherein said molded body is integrally formed with a tubular portion extending continuously from the edge of the opening of said through-hole to the outside of said molded body and having substantially the same inner diameter as that of said through-hole.

7. The sensor unit according to claim 1, wherein said plurality of physical-quantity sensors include an acceleration sensor and a rotational-angular-velocity sensor.

8. The sensor unit according to claim 1, wherein:

each of said plurality of physical-quantity sensors has substantially the same height dimension; and

said molded body has a portion extending between each of said physical-quantity sensors and an outer surface of said molded body on the side of said physical quantity sensor, and another portion extending between said lead and an outer surface of said molded body on the side of said lead, each of said portions having substantially the same thickness dimension.

9. The sensor unit according to claim 1, wherein said molded body have a portion covering the top-surface side of said lead and another portion covering the bottom-surface side of said lead, said portions being formed to have different tapered shapes from one another so as to allow the respective volumes of said portions to be substantially equalized.

10. The sensor unit according to claim 1, wherein at least one of said plurality of physical-quantity sensors and said signal-processing circuit are disposed, respectively, on the top and bottom surfaces of said lead in such a manner as to sandwich said lead therebetween.