Sumitomo Electric Industries, Limited

Hitachi Automotive Systems, Ltd.

Hitachi, Ltd.

Hiroyuki Yabe

Toshio Takagi

Yohei Katayama

Jiro Shinkai

Takashi Kato

Ryusuke Hirao

Takashi Nezu

Hiroki Ohara

Toru Uchino

Yasushi Fujimura

Atsushi Miki

Satoshi Yoshikawa

Takao Nakadate

Goro Sasaki

Yoko Watanabe

Kazuhiro Tanida

Shigeo Katayama

Satoshi Iguchi

[Object] The present invention provides a suspension control apparatus that allows miniaturization of a solenoid valve. [Solution] When a controller is started up by a power source controller (a power source unit), the controller switches a control current from 0 ampere to a maximum current value I6 at the same time as the startup. After that, the control shifts to normal control. As a result, even if a hysteresis of a damping force characteristic is large relative to the control current, it is possible to promptly move a solenoid valve to a position to be used in the normal control.

Suspension control apparatus

During either of the extension and compression strokes, hydraulic liquid flows from a cylinder upper chamber into a reservoir through an annular passage and a damping force control mechanism, and a damping force is generated by the damping force control mechanism. The check valve is provided with a sub-check valve in parallel thereto, which opens in a very low piston speed region to allow the hydraulic liquid to flow through an orifice passage. These check valves are opened successively as the piston speed increases, thereby generating a sufficiently small damping force in the very low piston speed region during the compression stroke of the piston rod, and obtaining a moderate damping force when the piston speed increases.

Damping force control type shock absorber

A damping force adjustable hydraulic shock absorber, in which response delay of a pressure control valve and self-excited vibration of a valve body can be prevented. A damping force is generated by controlling an oil flow between an annular oil passage () and a reservoir () generated by sliding movement of a piston in a cylinder with use of a back-pressure type main valve () and a pressure control valve (). The damping force is directly generated by the pressure control valve, and valve-opening pressure of the main valve is adjusted by adjusting an inner pressure of a back-pressure chamber. In the pressure control valve, a valve spring is disposed between a valve body and a plunger. A mass of the valve body is sufficiently less than that of the plunger, and a spring stiffness of the valve spring is higher than that of a plunger spring.

Damping force adjustable shock absorber

[Object] The present invention provides a suspension control apparatus that allows miniaturization of a solenoid valve. [Solution] When a controller is started up by a power source controller (a power source unit), the controller switches a control current from 0 ampere to a maximum current value Iat the same time as the startup. After that, the control shifts to normal control. As a result, even if a hysteresis of a damping force characteristic is large relative to the control current, it is possible to promptly move a solenoid valve to a position to be used in the normal control.

A rod acceleration reducing mechanism is provided in a bottom-side oil chamber in an inner tube. The rod acceleration reducing mechanism includes a housing having a cylindrical accommodating casing screwed onto a fastening bolt of a bottom valve and a cap, a free piston displaceably fitted in the housing to define variable chambers at vertically opposite sides thereof, and elastic disks applying an elastic resistance to the displacement of the free piston. The variable chambers formed in the housing are variable in volume in response to pressure changes in the bottom-side oil chamber and the reservoir chamber. Thus, rod vibration can be generated by the rod acceleration reducing mechanism to reduce generation of rapping noise during running of the vehicle.

Shock absorber

The present invention provides a new arrangement of the stem and the cap resistance-welded to the stem, in which the deformation induced by the welding in a portion adjacent to the projection does not cause the failure for the assembly of the module. The cap and the stem of the present module provided first and second portions. The diameter of the second portion is greater than that of the first portion such that, even the welding deforms the first portions of the cap and the stem; the deformed portion is inside of respective second portions.

Optical module with metal stem and metal cap resistance-welded to stem

The present invention provides a receiving optical subassembly (ROSA) with a co-axial shape and a stem for mounting semiconductor devices thereon that improves the high frequency performance of the ROSA. The ROSA mounts a photodiode (PD) and a pre-amplifier on a stem and the stem has a hollow the PD and the pre-amplifier are mounted therein. Since the hollow has a depth substantially equal to a thickness of the pre-amplifier, the bonding wire from the pre-amplifier to the surface of the stem may become shortest to reduce the parasitic inductance of the bonding wire and to enhance the high frequency performance of the ROSA.

Receiving optical subassembly with an improved high frequency performance

The object of the present invention is to provide an optical module for the WDM communication system, in which the oscillation wavelength is on the grid of the WDM regulation, moreover the optical output power and the oscillation wavelength can be controlled independently. The present module comprises a semiconductor light-emitting device, a wedge shaped etalon device and two light-receiving devices. The etalon device contains a first portion, on which the anti-reflection films are coated, and a second portion. One of the receiving devices detects light transmitted through the first portion of the etalon device, while the other device detects light through the second portion. Signal from the former device controls the output power of the light-emitting device, while the signal from the latter receiving device controls the oscillation wavelength of the laser.

Optical module

An optical assembly of the present invention comprises a package installing a semiconductor optical device therein, a metal sleeve attached to the package, and the resin holder disposed between package and the sleeve member. When this optical assembly is installed within the optical transceiver and even the metal sleeve extrudes into the optical receptacle and is exposed to the outside there, the EMI noise can be prevented from importing into the transceiver and radiating to the outside, because the resin holder made of substantially insulating material is disposed between the sleeve and the package.

Optical sub-assembly having an enhanced discharge-resistant arrangement and an optical transceiver using the same

The light-emitting module includes a semiconductor light-emitting device, a first optical detector for monitoring the magnitude of light emitted from the semiconductor device, a second optical detector for monitoring an oscillation wavelength of the semiconductor device, and an Etalon. The first detector is located in a position where the wavelength variation of the transmitted light from the Etalon is relatively small, while the second detector is located in a position where the wavelength variation of the transmitted light is relatively large. The geometrical size of the second detector along the first direction is wider than that along the second direction normal to the first direction; this thus enhances the efficiency of wavelength sensitivity.

The object of the present invention is to provide an optical module for a WDM communication system, in which the oscillation wavelength is on the grid of the WDM regulation. The optical output power and the oscillation wavelength can be controlled independently. The present module includes a semiconductor light-emitting device, a wedge shaped etalon device and two light-receiving devices. The etalon contains a second portion, on which anti-reflection films are coated, and a first portion. One of the receiving devices detects light transmitted through the second portion of the etalon, while the other device detects light through the first portion. A signal from the former device controls the output power of the light-emitting device, while a signal from the latter receiving device controls the oscillation wavelength of the laser.

A main portion of an optical module includes a thermoelectric cooler and a chip carrier placed on the cooler A semiconductor light-emitting device a lens photodetectors , and an etalon are directly or indirectly mounted on the chip carrier . Supporting members and are also fixed on the chip carrier . A roof is supported by the supporting members and positioned above the etalon The roof supporting members and chip carrier are maintained at substantially equal temperatures by the cooler As a result, the temperature of the etalon is stabilized, and therefore the variation in the lock wavelength is suppressed.

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Yokohama, Japan

Hiroyuki Yabe