Mitsubishi Denki Kabushiki Kaisha

Tadashi Kimura

Tsutomu Inaba

Masahiro Sugihara

Toshiyuki Nakamura

Norihide Kobayashi

Etsuo Morishita

Masahiko Oide

Masayuki Kakuda

Tetsuzo Matsugi

Hitoshi Tada

Nobuaki Kaneno

Tatuya Kimura

Kenzo Mori

Yuji Okura

Yoshitatu Kawama

Yutaka Mihashi

Motoharu Miyashita

Yasuyuki Suzuki

Takushi Itagaki

Nobuyoshi Ogasawara

Hiromu Narumiya

Tsutomi Inaba

Katuhiko Goto

A method for fabricating a semiconductor laser includes forming a double heterojunction structure on a first conductivity type semiconductor substrate; forming the double heterojunction structure into a stripe mesa shape by selective etching; successively growing a first conductivity type layer, a second conductivity type current blocking layer, and a first conductivity type current blocking layer on opposite sides of the mesa to embed the mesa; and adding an impurity from a surface of the first conductivity type current blocking layer to form impurity doped regions that electrically separate the second conductivity type current blocking layer from an upper part of the mesa at opposite sides of the mesa.

Method of making semiconductor laser

In a method for evaluating thickness of a semiconductor layer epitaxially growing on a main surface of a substrate, a parallel stripe-shaped ridges extending are formed on the surface of the substrate, and a semiconductor layer is epitaxially grown on the surface of the substrate including the stripe-shaped ridges while irradiating the stripe-shaped ridges with light and monitoring from the stripe-shaped ridges to evaluate the thickness of the epitaxially growing semiconductor layer. The thickness of the epitaxial layer is evaluated with high precision during the epitaxial growth process.

Method for evaluating epitaxial layers and test pattern for process

In a method of fabricating an integrated semiconductor light modulator and laser device, a semiconductor layer having first and second regions of different crystal compositions is produced on each chip region of a semiconductor wafer by a selective crystal growth using, as a mask, a dielectric film having a prescribed pattern. Thereafter, a semiconductor laser and a light modulator that modulates laser light emitted from the semiconductor layer are produced in a first semiconductor region and a second semiconductor region, respectively, of each chip region. In this method, the shape of the dielectric mask pattern and the shape of the opening of the mask pattern on each chip region is symmetrical with the dielectric mask pattern and opening of an adjacent chip region along the optical waveguide direction of the semiconductor laser. The semiconductor layer is grown on the wafer so that the first and second semiconductor regions of different crystal compositions on each chip region are in contact with semiconductor regions having the same crystal composition of an adjacent chip region. As the result, at opposite edges of the chip region in the optical waveguide direction, the crystal compositions of the first and second semiconductor regions are the same.

Method of fabricating an integrated semiconductor light modulator and

A semiconductor laser includes a first conductivity type semiconductor substrate; a double-heterojunction structure including a first conductivity type cladding layer, an active layer, and a second conductivity type cladding layer successively disposed on the semiconductor substrate; two parallel stripe grooves forming the double-heterojunction structure in a mesa shape; a first conductivity type mesa embedding layer, a second conductivity type current blocking layer, and a first conductivity type current blocking layer successively disposed on the semiconductor substrate and contacting opposite sides of the mesa; and impurity doped regions formed by adding an impurity through the surface of the first conductivity type current blocking layer. The impurity doped regions electrically separate an upper part of the mesa from the second conductivity type current blocking layer at opposite sides of the mesa. Since the second conductivity type current blocking layer is not in contact with the mesa structure, no leakage current path is formed in the laser structure.

Semiconductor laser

A scroll compressor comprises a compression mechanism comprising a combination of a fixed scroll and an orbiting scroll; a main shaft for driving the orbiting scroll; an electric motor rotor and stator for driving the shaft; a first bearing frame for supporting the orbiting scroll in the axial direction through a bearing; a second bearing frame for supporting the shaft in the radial direction through a bearing; a hermetic shell including the compression mechanism in an upper portion, the rotor and stator in a lower portion, and an suction pipe for inspiring a working fluid; and a dividing chamber arranged in the shell so as to communicate with the suction pipe and having efflux holes for directing the inspired working fluid to the compression mechanism in the upper portion, the stator and rotor in the lower portion, and an upper coil end of the stator placed in a position lateral to the chamber.

Scroll compressor with dividing chamber for suction fluid

A scroll type compressor, wherein the oil feeding passage of the thrust bearing to be interposed between the orbiting scroll member and the bearing support is so constructed as to having its terminal part within a plane of the thrust bearing, and a part of each of the passages is made to open at a position where it is intermittently communicating with the guide grooves of the orbiting scroll member.

Scroll compressor with oil feeding passages in thrust bearing

A scroll compressor comprising a driving scroll and a driven scroll which is combined with the driving scroll and is driven by the driving scroll through an Oldham's coupling, a partition plate fixed to a container for housing the structural elements such as scrolls and having a supporting pin provided at a position near the inner wall of the container, a movable bearing support which is placed below the partition plate and is engaged with the supporting pin so as to be swingable around the supporting pin, and which supports the driven scroll through a bearing, and a rotation controlling structure which causes a swinging movement of the movable bearing support around the supporting pin along with a driven scroll whereby the distance between the axial centers of said driving and driven scrolls is changed.

Scroll compressor with control of distance between driving and driven

A scroll-type compressor is disclosed which has a novel thrust bearing for supporting an orbiting scroll. The thrust bearing is annular and is supported by a bearing support frame which has a plurality of oil return holes formed therein. The diameter of the thrust bearing is smaller than the diameter of the orbiting scroll and of an Oldham coupling which guides the orbiting scroll. The thrust bearing has a plurality of oil passageways for lubricating oil formed therein whose inner ends open onto the central hole and whose outer ends communicate with the oil return holes and do not extend to the outer periphery of the bearing. The oil passageways are always covered by the orbiting scroll. In one form of the invention, the oil passageways are in the form of grooves formed in the upper surface of the bearing and through holes which communicate between the outer ends of the grooves and the oil return holes. In another form of the invention, the oil passageways are slits formed through the depth of the bearing. In another form of the invention, the oil passageways are a combination of slits formed through the depth of the bearing, through holes which communicate with the oil return holes, and grooves formed in the upper surface of the bearing which extend between the slits and the through holes.

Scroll-type compressor with oil passageway in thrust bearing

A scroll compressor is provided with a main shaft to drive an orbiting scroll whereby fluid in a compression chamber which is formed by combining a stationary scroll with the orbiting scroll is compressed and then is discharged from the scroll compressor. To prevent a refrigerant gas in an eccetric recess formed in the main shaft from mixing with a lubricating oil, a conduit is formed in the main shaft to communicate the eccentric recess with a space between the lower part of the orbiting scroll and the upper part of the main shaft.

Scroll compressor with pressure-equalizing passage and gas vent conduit

In a scroll type compressor, the shaft of a driven scroll is rotatably supported in a sealing container so that the axis of rotation of the driven scroll shaft is deviated from the axis of rotation of a driving scroll; the wrap plates of the driving and driven scrolls are mutually combined with each other so that the parts of the side surface of the wrap plates come in contact with each other to form a compression chamber; and the driven scroll is directly driven by the driving scroll in synchronism therewith, whereby the function of compression of a fluid is obtainable during the movement of the compression chamber toward the centers of the driving and driven scrolls.

Scroll compressor with driving and driven scrolls

A scroll compressor comprises an orbiting scroll and a stationary scroll, both being mutually combined to form a compression chamber therebetween. The scroll compressor is provided with a lubricating oil feeding system to lubricate each bearing constituting a contact-sliding and contact-rotating part. A special arrangement of oil grooves is made in a thrust bearing supporting the orbiting scroll in such a manner that pressure loss in the oil grooves of the thrust bearing is greater than a pressure raised by the third oil pump means so that there causes no negative pressure at the inlet port of a radial oil feeding conduit and the outlet of the vertical oil feeding passage in the main shaft.

Scroll compressor with oil grooves in thrust bearing

A scroll compressor comprises a driving scroll and a driven scroll which is combined with the driving scroll and is driven by the driving scroll through an Oldham's coupling, a partition plate fixed to a container for housing the structural elements such as scrolls and having a supporting pin provided at a position near the inner wall of the container, a movable bearing support which is placed below the partition plate and is engaged with the supporting pin so as to be swingable around the supporting pin, and which supports the driven scroll through a bearing, and a rotation controlling means which causes a swinging movement of the moveable bearing support around the supporting pin along with the driven scroll whereby the distance between the axial centers of said driving and driven scrolls is changed.

A scroll-type apparatus having an improved radial seal and a method for the assembly thereof is disclosed. The spiral wrap of a moving scroll and a stationary scroll are provided with gap adjusting means for providing a gap of a desired size between the top surface of the spiral wrap of each scroll and the top surface of the base plate of the opposing scroll. The gap adjustment means comprises a spiral-shaped elastic element which fits into a groove formed in the top surface of a spiral wrap or on top of a protrusion formed on the top surface of the spiral wrap, to form a nonpressurized seal. The elastic element is supported by the spiral wrap by friction, bonding, or solvent welding.

Method for the assembly of a scroll-type apparatus

A scroll-type apparatus having a main journal bearing which journals the drive shaft of the apparatus and is capable of pivoting by small angles with two degrees of freedom. The main journal bearing comprises three or more arcuate pads whose inner surfaces journal the drive shaft and which are pivotably supported by a stationary main bearing housing. In a preferred embodiment, each of the pads has a spherical protrusion and two rotation-preventing pins secured to its back surface. The protrusions contact the inner surface of the main bearing housing and pivotably support the pads, while the rotation-preventing pins are inserted into grooves formed on the inner surface of the main bearing housing. When a load is applied to the drive shaft causing it to tilt, the pads of the main journal bearing can tilt along with the drive shaft by pivoting about the points of contact between the spherical protrusions and the inner surface of the main bearing housing, thereby preventing edge loading of the main journal bearing.

Scroll-type apparatus having a pivoting main journal bearing

A scroll-type fluid transferring machine comprises a stationary scroll member and an oscillatable scroll member, each of which has a spiral wrap of an involute curve or other curves projecting from a base plate and which cooperate to form a compression chamber between the spiral wraps and the base plates by mutually fitting one into the other, an oscillatable scroll shaft provided on the surface of the base plate at the position opposite the spiral wrap of the oscillatable scroll member, a crank shaft having an eccentric recess having its axis which is shifted by a predetermined distance from the axis of the crank shaft, wherein a cylindrical bush having the coaxial outer and inner circles is loosely fitted in the eccentric recess of the crank shaft with a gap between the outer circumference of the bush and the inner wall of said eccentric recess, and the shaft of the oscillatable scroll member is fitted in the inner circumference of the bush in a freely rotatable manner.

Growing community of inventors

Wakayama, Japan

Tadashi Kimura