Denso Corporation

Nippondenso Co., Ltd.

Kyosan Denki Co., Ltd.

Shigeru Nonoyama

Takamoto Watanabe

Naoki Mitsumata

Shigenori Yamauchi

Fumiaki Murakami

Yukihiro Takeuchi

Toshiyuki Yonemoto

Yoshihiko Ooya

Osamu Takamisawa

Hiroaki Itou

An electromagnetic valve includes a rod, an armature fixed to the rod, and a stopper that limits motion of the armature to one side in an axial direction of the rod. The armature has a rod hole through which a fixed portion of the rod extends to be fixed to the armature. The rod includes a flange portion that is located on the one side in the axial direction with reference to the fixed portion. The flange portion is larger than the fixed portion in a radial direction of the rod. The armature includes a contact portion adjacent to an opening of the rod hole that is open toward the one side in the axial direction, and the contact portion contacts the flange portion.

Electromagnetic valve

A filter element is formed from a filter material configured to capture a foreign substance in fuel. A lower case is attachable to and detachable from a bottom portion of a housing in a movable direction. The housing and the lower case are configured to accommodate the filter element. The filter element defines a passage extending through the filter element in the movable direction. The passage is configured to accommodate the component. The component is configured to be attached to and detached from the housing together with the lower case when the lower case is attached to and detached from the housing.

Fuel filter device

An object of the invention is to provide a depressurizing valve mounted to a common rail for a fuel injection device, in which a direction of a connector for the depressurizing valve can be adjusted, without affecting an air gap and a sealing performance. The depressurizing valve has a valve unit and a coil unit which is detachably assembled to the valve unit by a mounting member, such as a retaining nut. A valve housing has an inside space, which is fluid tightly separated into first and second spaces by a connecting member, which is fluid tightly connected to the valve housing and a stator core. A valve body and a spring are arranged in the first space for closing a flow control port. A cylindrical coil is accommodated in the second space, such that the coil is rotatable with respect to the valve housing.

Depressurizing valve and fuel injection device

A solenoid valve includes a coil, a stator core, a valve member, a coil spring, and a stopper. The coil provides a magnetic field when the coil is energized. The stator core includes a receiving bore, wherein the stator core generates a magnetic attractive force when the coil is energized. The valve member is attracted toward the stator core due to the magnetic attractive force generated by the stator core. The coil spring is received in the receiving bore of the stator core, wherein the coil spring biases the valve member in an opposite direction opposite from the stator core. The stopper positions the coil spring such that an outer peripheral surface of the coil spring is separated from an inner peripheral surface of the receiving bore.

Solenoid valve

A capacity(ies) of a variable capacitor(s) varies with a physical amount. A C-V conversion circuit converts variation in the capacity into a voltage signal. First and second charge holding circuits hold the voltage signal at different timings as first and second charges, respectively. An offset compensating charge holding circuit generates and holds an offset charge for compensation of an offset in the voltage signal. A charge combining and holding circuit combines and holds the first and second charges and the offset charge. An outputting circuit receives the combined charge from the charge combining and holding circuit and outputs an output voltage signal corresponding to the physical amount in accordance with the received charge. The outputting circuit, the offset compensating charge holding circuit, the C&equals;V circuit may be omitted. The variable capacitance may include a capacitor or a differential type capacitors.

Signal processing apparatus

A capacitive physical-quantity detection apparatus includes a movable electrode (,) which is displaced in response to a physical quantity. A fixed electrode (,) opposed to the movable electrode forms a capacitor in conjunction with the movable electrode. A signal applying device (,) operates for applying a first signal between the movable electrode and the fixed electrode. The first signal is periodic, and has at least a first time period for detection of a capacity variation and a second time period for displacement of the movable electrode to implement self diagnosis. A C-V conversion circuit (,) operates for generating a voltage which depends on a variation in a capacitance of the capacitor during the first time period. A signal processing circuit (,) operates for processing the voltage generated by the C-V conversion circuit into a second signal depending on the physical quantity. A changing device (,) operates for changing the first signal in the second time period between a state for execution of self diagnosis and a state for unexecution of self diagnosis. The first signal in the state for execution of self diagnosis applies a pseudo physical quantity to the movable electrode.

Capacitive physical-quantity detection apparatus

A physical quantity detecting is capable of easily adjusting sensitivity and an offset of a detected output without being increased in size. In a signal processor for driving a sensor element in which fixed electrodes are disposed on both sides of a movable electrode displaced in response to acceleration, a signal generator generates PWM signals PA and PB in which an invalid control period during which the fixed electrodes are both deenergized only during a period corresponding to data M3 stored in a memory, is, at a predetermined ratio, inserted into a valid control period during which the fixed electrodes are alternately energized and their energization ratio is controlled so that the movable electrode is placed in position. Since the sensitivity of the sensor element to the acceleration changes according to the length of the invalid control period which does not contribute to control of the position of the movable electrode, its sensitivity can be easily adjusted by simply changing the value set in the memory.

Physical quantity detecting device

A physical amount detecting apparatus, preferably, an acceleration sensor, includes a sensor element, an A/D converter, a control unit and an activation unit. The sensor element is activated by a supply voltage and outputs an electric signal in accordance with a predetermined physical amount. The A/D converter digitizes an analog electric signal and outputs digital data. The control unit calculates a control amount in order to control the sensor element, as the electric signal is set to a predetermined output, based on the digital data, and generates a control signal in accordance with the control amount. The activation unit activates the sensor element in accordance with the control signal. As a result, the control unit outputs a detecting signal indicating a physical amount in accordance with the control amount or the control signal.

Physical quantity detecting apparatus

In an acceleration sensor having movable gates and a movable electrode and having a signal processing portion, the movable gates generate a differential voltage from acceleration in one direction and its output signal is fed back to the movable electrode. The balance of the movable portion is kept using an electrostatic force which cancels the acceleration acting on the movable portion, and signal detection is stabilized using closed loop control. Since signal detection is on a differential basis, acceleration can be detected in only one direction. Since a change in current is detected as a voltage difference, no carrier wave is required. Since MISFETs having movable gates are formed in pairs, there is no influence of temperature drifts. The use of a differential signal similarly cancels the influence of fluctuations of the power supply. Configuration of an acceleration sensor is thus simplified.

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Nishikamo-gun, Japan

Shigeru Nonoyama