Kabushiki Kaisha Toyota Chuo Kenkyusho

Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Kentaro Mizuno

Shoji Hashimoto

Yoshiteru Omura

Kouji Tsukada

Jiro Sakata

Takashi Katsumata

Rie Taguchi

Hidenori Moriya

Hiromichi Yasuda

Yumi Masuoka

Yuji Nishibe

Norikazu Ohta

Norio Fujitsuka

Keisuke Gotoh

Kouhei Yamaguchi

Yoshie Ohira

Yoshiharu Takemoto

Hideto Shimada

A force detection device includes: a substrate; and a force transmission block. The substrate includes: a mesa gauge arranged on a principal plane of the substrate and providing a bridge circuit; a connection region arranged on the principal plane; and a sealing portion surrounding all around the mesa gauge and connected to the force transmission block. The mesa gauge includes: a first mesa gauge extending in a first direction; and a second mesa gauge extending in a second direction and spaced apart from the first mesa gauge. The connection region electrically connects the one end of the first mesa gauge and the one end of the second mesa gauge.

Force detection device

A force detection apparatus includes a substrate and a force transmission block. The substrate includes: a high-sensitive mesa gauge that is provided on a main surface, extends in a first direction to produce a relatively large change of an electric resistance in accordance with compressive stress, and includes a top surface; a low-sensitive mesa gauge that is provided on the main surface, extends in a second direction to produce a relatively small change of an electric resistance, and includes a top surface; and a mesa lead that is provided on the main surface, extends in a third direction, and includes a top surface. The force transmission block contacts the top surface of the high-sensitive mesa gauge and the top surface of the low-sensitive mesa gauge, and is non-contact with at least a part of the top surface of the mesa lead.

Force detection apparatus having high sensor sensitivity

A force detection device includes: a substrate that includes a power supply wire, a reference wire, a first output wire, a second output wire and first to fourth mesa gauges extending along a first direction; and a force transmission block connected to the substrate. A pair of the first and second mesa gauges and a pair of the third and fourth mesa gauges are connected in parallel to each other between the power supply wire and the reference wire. The first output wire is connected between the first and second mesa gauges. The second output wire is connected between the third and fourth mesa gauges. A contact area of the force transmission block with a first pair of the first and fourth mesa gauges is different from a contact area of the force transmission block with a second pair of the second and third mesa gauges.

A time measuring circuit is provided with an oscillating circuit configured to generate a low-speed clock signal and a high-speed clock signal; and a measuring circuit configured to measure target time based on clock number of the low-speed clock signal and the high-speed clock signal outputted from the oscillating circuit, wherein the low-speed clock signal has a relatively low frequency and the high-speed clock signal has a relatively high frequency. The oscillating circuit is configured to switch from outputting the low-speed clock signal to outputting the high-speed clock signal when elapsed time from when a measurement of the target time started reaches a set value, and the set value is calculated by subtracting a predetermined value from a preliminary value which is provided by a preliminary measurement measuring the target time using only the low-speed clock signal.

Time measuring circuit and temperature sensor circuit

A pressure sensor includes a diaphragm, a coupling portion coupled to the diaphragm, and two pressure receiving elements. Each pressure receiving element outputs an output signal that changes according to the temperature and the pressure applied to a pressure receiving surface and has an output characteristic that represents the relationship of the output signal to the pressure and the temperature. The two pressure receiving elements have the same output characteristics. The pressure receiving surface of one of the two pressure receiving elements is connected to the diaphragm through the coupling portion, and the pressure receiving surface of the other pressure receiving element is disconnected from the diaphragm. The pressure sensor outputs a signal that is in accordance with the difference between voltages of the two pressure receiving elements.

Pressure sensor

A capacitive sensor device includes first and second sensor capacitors coupled in series, a clock signal generating part, an operational amplifier, a feedback capacitor, a compensating capacitor, and a compensating signal generating part. The clock signal generating part generates a first clock signal and the second clock signal applied to the first and second sensor capacitors, respectively. The compensating signal generating part generates a compensating signal applied to the compensating capacitor. The first clock signal and the second clock signal have the same frequency and the same amplitude and have phases being opposite each other. The compensating signal has a frequency same as the first clock signal and the second clock signal, has a phase same as one of the first clock signal and the second clock signal, and has an amplitude that is adjustable.

Capacitive sensor device

A temperature compensated force detection element is provided with a substrate, an insulation layer disposed above the substrate, and a p-type semiconductor layer disposed above the insulation layer, and a positive electrode and a negative electrode disposed apart from each other above the p-type semiconductor layer. A gauge portion being electrically connected to the positive electrode and having a higher impurity concentration than the p-type semiconductor layer, and an n-type region electrically connected to the negative electrode are formed in the p-type semiconductor layer.

Force detection element

A stress measurement device includes a current supply portion; a series circuit which is connected to the current supply portion and has a piezoresistive element that forms a single gauge resistance and a compensating diode that is connected in series to the piezoresistive element; and a voltage measuring portion that measures voltage between both ends of the series circuit. The single gauge resistance has a piezoresistive effect in which a resistance value changes according to applied stress, and a positive temperature characteristic in which the resistance value increases depending on an increase in temperature. The compensating diode is provided in a forward direction with respect to the current supply portion and has a negative temperature characteristic in which a voltage between an anode and a cathode of the compensating diode decreases depending on the increase in temperature.

Stress measurement device and stress measurement method

A force sensing element is provided with a gauge portion and a plurality of electrodes. The gauge portion is formed of an n-type semiconductor substrate whose (100)-face serves as a main face, a p-type semiconductor substrate whose (110)-face serves as a main face, or a p-type semiconductor substrate whose (111)-face serves as a main face, and is pressed in a thickness direction of the semiconductor substrate upon receiving a force. The electrodes are electrically connected to the gauge portion such that a current path extending in a direction corresponding to the thickness direction of the semiconductor substrate is formed in the gauge portion. The force sensing element thus constructed makes it possible to detect a force with high precision.

Force sensing element

Force detection devices may have high detection precision and may prevent current leakage through a strain gageto the outside. For example, a force detection blockmay include a semiconductor substrate, a first insulating layerand a semiconductor layer(strain gage). The strain gagepreferably includes a site where resistance changes in accordance with the stress acting thereon. The strain gagepreferably constitutes at least a portion of a ridgeprojects from the surface of the force detection block. A force transmission blockmay be attached to a top surface of the ridge. The width of the first insulating layeris preferably greater than the width of the semiconductor layer

Piezoresistive transducers

A pressure sensor has a housing having a first block and a second block provided therein. A force to be measured applies upon a upper face of the first block. An upper face of the second block makes contact with a base face of the first block. Piezoresistive elements are formed within the base face of the first block. The resistance values of these piezoresistive elements change as contacting pressure between the first block and the second block changes. A first electrode is formed on an upper face of the first block. A second electrode is formed on a base face of the second block. Electrical characteristics between the first electrode and the second electrode change following change in the contacting pressure between the first block and the second block.

Force sensors

A pressure sensor is realized wherein output error of sensor element can be reduced even in the case where the pressure sensor is utilized in high temperature conditions. A pressure sensor is provided with a housing, a diaphragmthat partitions the interior and the exterior of the housing, a sensor elementprovided within the housing, output value of the sensor elementvarying in accordance with force exerted thereupon, and a force transmitting rodprovided within the housing, the force transmitting rodmoving downwardly when a pressure is exerted upon the diaphragm, the force transmitting rodthereby exerting force upon the sensor element. The diaphragmhas a central regioncontacting with the force transmitting rod, and a surrounding regionsurrounding the periphery of the central regionand connecting the central regionwith the housing. The surrounding region, viewed cross-sectionally along the radius, is V-shaped or U-shaped, and cancels thermal expansion.

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Nisshin, Japan

Kentaro Mizuno