Abstract: The height of a bead opposing a joint where side edges of a plate are to be joined is set to be smaller than the height of a bead which does not oppose the joint by the thickness of the plate. Further, lands are provided between the beads and protrude from either the tube surface or the tube surface toward the inside of the main tube unit, and flow gaps are formed through which the heat-exchange medium flows over the lands.

Abstract: To resolve a problem of decreasing a heat exchange rate of a refrigerating cycle owing to a large amount of a refrigerator oil delivered from a discharge pipe to the refrigerating cycle, there is provided a sealed compressor driven by a motor having a compressor unit and a motor unit in which a ring is provided at an outer periphery of a coil end of a stator on a side of the compressor unit to reduce the amount of delivering the refrigerator oil to the refrigerating cycle and a shape of a balance weight of a rotor on the side of the compressor unit is formed in a cylindrical shape a portion of a side face of which is opened and an end face of which is flat to thereby reduce stirring of fluid.

Abstract: The present invention also provides another semiconductor multilayer carrier injection structure in a semiconductor laser. The semiconductor multilayer carrier injection structure comprises the following elements. The semiconductor multilayer carrier injection structure includes a multiple quantum well active layer comprising alternating laminations of quantum well layers made of a first compound semiconductor having a first energy band gap and potential barrier layers made of a second compound semiconductor having a second energy band gap larger than the first energy band gap. Each of the quantum well layers has an electron ground state of quantum energy levels of electrons and a hole ground state of quantum energy levels of holes. The semiconductor multilayer carrier injection structure also includes a first carrier injection guide layer being provided in contact with a first lateral end portion of the multiple quantum well active layer.

Abstract: A rosin emulsion sizing agent for paper making comprising a rosin substance, a dispersing agent and water, the rosin substance comprising (a) a rosin or a fortified rosin and (b) a rosin ester or a fortified rosin ester, the dispersing agent comprising a (meth)acrylamide copolymer obtained by polymerizing a polymerizable monomer mixture containing (A) 70 to 95% by mole of (meth)acrylamide, (B) 0.5 to 10% by mole of a sulfo (salt) group-containing monomer or a phosphoric acid (salt) group-containing monomer and (C) 1 to 20% by mole of a hydrophobic monomer, and a method for paper sizing using the same.

Abstract: A multiquantum-well semiconductor laser having a long wavelength, for use in optical communication systems, comprises an active region including a plurality of quantum-well layers each made of InGaAs or InGaAsP, and a plurality of barrier laminates each made of InGaAsP having a bandgap wider than that of the quantum-well layers. Each barrier laminate includes three barrier layers of different compositions of InGaAsP having different bandgaps. Each barrier laminate has a thickness such that the wave functions of carriers in adjacent quantum-well layers do not overlap each other, while carriers supplied to the active region can be effectively injected into the quantum-well layers, thereby obtaining a low threshold current and a high slope efficiency.

Abstract: Disclosed herein is a long wavelength multiple quantum well semiconductor laser which is capable of preventing the nonuniform injection of carriers into quantum wells, and the overflow of the electrons within the quantum wells, and which is also capable of suppressing the increase in the threshold caused by insufficient gain, and the increase in the threshold and the deterioration in the slope efficiency caused by internal absorption loss.

Abstract: An optical recording apparatus for automatically compensating for focus offset which cannot be compensated for with a conventional focus servo circuit. A plurality of auxiliary signals differing from one another in the frequency domain is generated, a rotational synchronism signal is generated by detecting an index mark put on the optical disk in advance to indicate the reference point of the rotational phase, and a switching signal is generated in response to the rotational synchronism signal. In response to the switching signal, a plurality of auxiliary signals and an information signal are consecutively outputted and recorded onto a track of the optical disk.

Abstract: This invention provides a dispersing agent suitable for the production of an aqueous rosin emulsion which contains as an active ingredient a copolymer salt containing a certain oxyalkylene-containing monomer unit and a tertiary and/or quaternary nitrogen-containing monomer unit and a dispersing agent suited to the production of aqueous rosin emulsions which contains at least one member of units of quaternary nitrogen-containing monomer having a hydroxyl group, units of quaternary nitrogen-containing monomer having a vinylbenzyl group and units of quaternary nitrogen-containing monomer having a maleimide group and at least one member of hydrocarbon monomer units and (meth)acrylate ester monomer units.The invention further provides an aqueous rosin emulsion as prepared using the above dispersing agent and a sizing agent containing the emulsion as an active ingredient.

Abstract: An apparatus for optically recording/reproducing data to/from a disc including a focus servo circuit which initially sets an objective lens of an optical head to a predetermined setting. This predetermined setting is such that a laser beam passing through the lens is focused on the disc at a point inside of the disc in the thickness direction. Then, the focus servo circuit fine tunes the objective lens position until the laser beam is focused onto a recording film located inside of the disc.

Abstract: An optical recording apparatus for automatically compensating for focus offset which cannot be compensated for with a conventional focus servo circuit. A plurality of auxiliary signals differing from one another in the frequency domain is generated, a rotational synchronism signal is generated by detecting an index mark put on the optical disk in advance to indicate the reference point of the rotational phase, and a switching signal is generated in response to the rotational synchronism signal. In response to the switching signal, a plurality of auxiliary signals and an information signal are consecutively outputted and recorded onto a track of the optical disk.

Abstract: A multiple pole electrical connector includes a cylindrical metal shell (6); and insulation housing (7) placed within the metal shell and having a plurality of ground member recesses (20) formed on its circumferential surface; a plurality of detachable terminals (8) supported by the insulation housing, one of the detachable terminals serving as a ground terminal (9); and a detachable ground member (23) mounted on the ground terminal with a shell contact portion (24) thereof fitted in the ground member recess such that when the insulation housing is placed within the metal shell, the shell contact portion comes into close contact with an inside of the metal shell.

Abstract: An electrical plug (1) includes a conductive shell (6); an insulation housing (7) placed within the conductive shell and having at least one terminal mounting aperture (22); at least one detachable terminal (8) mounted in the terminal mounting apertures; a detachable ground terminal (9) mounted in the terminal mounting aperture; a retainer member (10) for retaining the detachable terminal and the detachable ground terminal; and a detachable ground member (23) attached to the ground terminal and having a comb contact (24) held between the conductive shell and the insulation housing.

Abstract: An apparatus and method for recording and reproducing information onto or from a rotating magnetooptic disc such that optimal laser power is maintained throughout the recording process. A test recording laser beam undergoes stepwise power changes as the recording position along a track of the disc changes. The recording signal is read out by a reproducing mechanism corresponding to the stepwise power change. A correcting mechanism utilizes the read-out signal to obtain the optimal power of the recording laser beam. Then, routine recording is carried out utilizing the optimal laser power. As routine recording is carried out, the optimal laser power is corrected depending upon the radial distance of the track being recorded from the center of the disc. As a result, optimal laser power is maintained regardless of the track position on the magnetooptic disc.

Abstract: A laser beam control circuit for an optical recording/reproducing apparatus, which controls the intensity of a laser beam striking a magneto-optical disc. The control circuit controls the injection current to a laser diode to provide high intensity for recording and low intensity for reproducing, providing a smooth transition between the high and low intensity states, and avoiding any excessive transition current. The control circuit monitors the output power of the laser diode and maintains it at a first value in the reproducing mode and a second value in the recording mode, and further controls the output power so that even during switching, the output power does not exceed the second level. This is done by supplying a compensating reference voltage to the recording power control loop during the reproducing mode, so that the output of the recording error amplifier does not change abruptly when the operating mode is switched to the recording mode.

Abstract: An electrical connector includes an insulating housing (100) consisting of a front section (111) and a rear section (112), the front section having a cylindrical contact support section (120) with a plurality of contact apertures (121) extending along its longitudinal axis and the rear section having a rear cavity (119) in a lower portion thereof; a plurality of L-shaped contact elements (300) each having a contact portion (301), an intermediate portion (302) extending rearwardly from the contact portion, and a terminal portion (303) extending downwardly from the intermediate portion, the contact portion being fitted into the contact aperture; and a block member (200) having a plurality of lateral channels (201) for receiving the intermediate portions and a plurality of vatical apertures (202) for receiving the terminal portions, the block member being fitted into the rear cavity so that the intermediate and terminal portions are fitted into the lateral channels and the vertical apertures respectively.

Abstract: An electrical connector which includes an insulating housing (30) containing a plurality of contacts (40); a cylindrical member for enclosing and supporting the insulating housing; and an insulating jacket (50) molded around the cylindrical member and a terminated section of a cable (70). The cylindrical member is divided into two semi-cylindrical sections (10, 20) in a plane parallel to its axis. The semi-cylindrical section (10) has a recessed joint edge or mortise and the semi-cylindrical section (20) has a projected joint edge or tenon corresponding to the recessed joint edge.

Abstract: Disclosed is a magneto-optic recording/reproducing apparatus capable of detecting small size defects in a magneto-optic recording disk in the order of tens of microns in size, and capable of reliably compensating for signal defects of a video image recorded on the disk. In the apparatus first and second photodetectors are provided for detecting information signals of two luminous fluxes into which a luminous flux emitted from a laser oscillator is divided by light splitting means. The photodetectors are arranged on the part of light reflected or emitted by the surface of a magneto-optic recording medium when it is irradiated with the luminous flux from the laser oscillator. According to the invention, the signals produced by the photodetectors are processed to produce a highly sensitive defect signal or a plurality of highly sensitive defect signals which may be summed together.

Abstract: A mounting structure includes an insulating housing (10) having an annular recess (14) extending rearwardly from a front end thereof for receiving a shell member of a mating connector; a metal end face protection member (40) attached to the front end and having a circular opening (41) for receiving the shell member; a pair of attachment sections (43) extend rearwardly from opposite sides of the end face protection member; a pair of leg members (45) extending downwardly from lower edges of the attachment sections to be secured to a printed circuit board (50); and a latch device (13B) provided within the insulating housing for engagement with the attachment sections whereby the end face protection member is locked to the insulating housing.

Abstract: An electrical connector has an insulating housing having an annular recess for receiving the shell member of a mating connector; a cylindrical shield member fitted in the annular recess, which includes shield contacts extending in radial directions from a front edge of the shield member; a detachable end face protection member attached to the front end of the insulating housing for protection thereof, which includes an latch member for latching the detachable end face protection member to the front end, whereby the shield contact comes into contact a backside of the end face protection member.

Abstract: An electrical connector includes an insulating housing having an annular recess extending rearwardly from a front end thereof and a shield member having a cylindrical wall fitted into the annular recess, a plurality of contact lugs extending outwardly in radial directions from a front edge thereof, and a leg member for connection with a shield circuit of a printed circuit board. The shield member has a plurality of first cantilever contacts bent outwardly and then inwardly forming an outward projection for contact with a metal shield provided on an inside of a mating shell member and a plurality of second cantilever contacts bent inwardly and then outwardly forming an inward projection for contact with a metal shield provided on an outside of the mating shell member.