Abstract: Virtual tracks are set so that the rotation center of a magnetic recording medium or the vicinity of the rotation center coincides with the track center of the data information, and positioning servo control is performed. Thus, since it is not necessary to faithfully follow the track center line specified by the servo information that is previously recorded on the magnetic recording medium or magnetooptical recording medium, a vibration is not easily caused in synchronism with the rotation. Therefore, when the rotation center and the pattern center are deviated from each other, since a vibration is not caused in synchronism with the rotation, the magnetic head of the magnetic recorder or the magnetooptical head of the magnetooptical recorder is able to follow tracks with higher precision. Accordingly, the recording density can be increased.

Abstract: A magnetic film having a high saturation magnetic flux density larger than 1.5 T and a resistivity larger than 40 .mu..OMEGA..cndot.cm is fabricated through an electroplating method using (40-60)Ni-Fe and by adding Co, Mo, Cr, B, In, Pd or the like to the (40-60)Ni-Fe. Thereby, it is possible to obtain a recording head capable of performing sufficient recording in a high frequency range and to obtain a disk storage system with a high recording density which has a transfer rate higher than 15 MB/s, a recording frequency higher than 45 MHz and a rotating speed of a magnetic disk higher than 4000 rpm.

Abstract: A leaking magnetic flux from a taper portion is canceled by utilizing an eddy current loss by using a magnetic head having a structure wherein at least a part of a magnetic pole constituting a magnetic path through a recording gap is sandwiched by conductive materials with respect to a track width direction, and a write blur quantity can be thus reduced. Further, magnetic saturation can be prevented by limiting a volume decrease at the distal end portion of the magnetic pole when the track width is reduced. Accordingly, the present invention can prevent magnetic saturation of the distal end portion of the magnetic pole resulting from the reduction of the width of the track of the recording head, can accomplish narrow-track recording by the recording head to a recording medium having high-coercive force and can reduce write blur.

Abstract: A lactic acid based by-product formed in a process of producing a lactic acid based composition is subjected to racemization in the presence or absence of a catalyst to thereby obtain a lactic acid component having substantially optical inactivity. Then, lactide or polylactic acid having optical inactivity can be obtained from the lactic acid component having the optical inactivity. The obtained lactide or polylactic acid is mixed with lactide or polylactic acid having an optical purity in a range of 90 to 100% e.e. at a predetermined ratio to thereby obtain lactide or polylactic acid having a desired optical purity.

Abstract: In order to prevent degradation of the recording performance during radio frequency recording, and to provide a thin film magnetic head and a recording reproducing sectional pattern magnetic head which has a magnetic pole width less than 2 .mu.m and an ultra high density magnetic storage apparatus of 10 Gb/ in.sup.2 grade, a recording head is provided in which a lower part magnetic film serves as a shielding film of a reproducing selection, a non magnetic gap film is formed during formation of the upper part magnetic film and the lower part magnetic film, one part of the lower part magnetic film or the upper part magnetic film has a higher resistivity of more than 80 .mu..OMEGA.cm than other parts, the upper part magnetic film is formed by flame galvanizing, and a gap section of the lower part magnetic film or the upper part magnetic film has a convex shape.

Abstract: A magnetoresistive head in which Barkhausen noise is substantially suppressed and a variation in reproduction is minimized, and a magnetic disk apparatus using the same magnetic head have been provided. The feature of the magnetic head and the magnetic disk apparatus of the invention resides in the provision of a longitudinal bias layer which comprises a hard magnetic thin film formed on an underlayer made of either a ferromagnetic thin film having a body-centered cubic lattice crystal structure, or an amorphous ferromagnetic thin film or antiferromagnetic thin film having a body-centered cubic lattice crystal structure.

Abstract: An intake system construction for an internal combustion engine includes a combustion chamber formed with upper and lower extremities thereof defined by a lower wall of a cylinder head and a top wall of a piston, an intake open end formed in the lower wall in opposition to the combustion chamber on one side of a reference plane which contains a central axis of the cylinder, an intake port formed in communication with the combustion chamber via the intake open end and extending upwardly from the intake open end so that a vertical swirl of inducted air is formed in the combustion chamber, an intake valve having a head portion for opening or closing the intake open end and a stem portion extending from the head portion to an upstream side of the intake port through the cylinder head, and a straightening member arranged in the intake port on a downstream side of the stem portion so that an inducted air flow is straightened on the downstream side of the stem portion.

Abstract: An intake system construction according to the present invention for an internal combustion engine is provided with a combustion chamber formed with upper and lower extremities thereof defined by a cylinder head and a piston, an intake open end arranged for being opened or closed by an intake valve, an exhaust open end arranged for being opened or closed by an exhaust valve, an intake port formed extending upwardly from the intake open end so that a vertical swirl of inducted air is formed in the combustion chamber, and an exhaust port for discharging combustion gas from the combustion chamber. The intake port is formed wider in one of halves thereof located adjacent a reference plane, which contains a central axis of a cylinder, than in the other half thereof located remote from the reference plane.

Abstract: An intake system construction according to the present invention for an internal combustion engine is provided with a combustion chamber formed with upper and lower extremities thereof defined by a cylinder head and a piston, an intake open end arranged for being opened or closed by an intake valve, an exhaust open end arranged for being opened or closed by an exhaust valve, an intake port formed extending upwardly from the intake open end so that a vertical swirl of inducted air is formed in the combustion chamber, and an exhaust port for discharging combustion gas from the combustion chamber. The intake port is formed wider in one of halves thereof located adjacent a reference plane, which contains a central axis of a cylinder, than in the other half thereof located remote from the reference plane.

Abstract: A cylinder head for an in-cylinder injection spark-ignition type internal combustion engine is formed with an injection passage for providing communication between a fuel injection valve and a combustion chamber. The injection passage includes a first and second passage sections disposed on the fuel injection valve side and on the combustion chamber side. The first passage section is formed, for example, into a truncated cone shape or a right circular cylindrical shape so that the cross sectional area decreases toward the fuel injection valve side or the area is constant over its entire length. The second passage section is formed to have the cross sectional area which increases toward the combustion chamber side. The fuel injected from the fuel injection valve flows into the combustion chamber via the injection passage having a gradually increasing cross sectional area, so that turbulence of fuel spray due to sudden divergent flow does not occur, resulting in an improved fuel combustion efficiency.

Abstract: This invention relates to an in-cylinder injection internal combustion engine. A lower wall of a cylinder head, said lower wall defining an upper wall of a combustion chamber, is configured in the form of a pentroof composed of an intake-valve-side, tilted, lower wall and an exhaust-valve-side, tilted, lower wall. A spark plug is arranged in the vicinity of a top part of the pentroof-shaped upper wall of the combustion chamber. A top wall of a piston, said top wall forming a lower wall of the combustion chamber, is configured in the form of a pentroof having an intake-valve-side, tilted, top wall and an exhaust-valve-side, tilted, top wall formed so that they correspond the intake-valve-side, tilted, lower wall and the exhaust-valve-side, tilted, lower wall of the cylinder head. A recessed portion is arranged in the intake-valve-side, tilted, top wall in the top wall of the piston.

Abstract: A magnetic digital storage method and system which can improve a recording density and can reduce a cross-talk upon reproducing. An inputted high-speed digital signal is converted to a plurality of low-speed digital signal sequences by a recording circuit and each of the low-speed signal sequence is recorded onto a plurality of adjacent recorded tracks of a recording medium by integrated parallel recording heads. One servo signal is commonly recorded to the plurality of recorded tracks. Further, when recording the digital signal to the adjacent recorded tracks of the recording medium, a delay of a signal that is applied to each recording head is adjusted such that the phases of magnetic transition points given by the recording signal in the adjacent recorded tracks are not identical in the circumferential direction.

Abstract: An internal combustion engine includes a cylinder head having a pair of upright intake ports formed therein on opposite sides of a plug hole extending along a cylinder axis, and each intake port has an upstream-side upright part extending from the top face of the cylinder head along the cylinder axis and a downstream-side slanting part having an intake opening communicating with a combustion chamber on one side of an imaginary plane containing the cylinder axis. An upper opening of each intake port opening in the top face of the cylinder head has a peripheral edge extending along the peripheral edge of an upper opening of the plug hole, and the peripheral edge of the upstream-side upright part extends along the outer surface of a lash adjuster.

Abstract: A device for securing a mirror in a projection television is disclosed. The device includes a cabinet having an aperture defined by edges. A shoulder element is located adjacent each of the edges, wherein each shoulder element extends underneath the aperture and is positioned for supporting peripheral edges of a reflection surface of the mirror. The device further includes a mirror cover plate located adjacent a back surface of the mirror and affixed to the cabinet. In addition, the device includes a securing element affixed between the back surface and the mirror cover plate for reducing deformation of said mirror.

Abstract: Described are a fuel injection control system and method, which are suitable for use in an engine of the system that fuel is injected in an intake pipe. It is the object of these system and method to perform good control on the injection quantity of fuel by precisely grasping evaporation characteristics of the fuel. To achieve this object, a direct feed rate at which a quantity of fuel out of a basic injection quantity is directly fed to a combustion chamber is set and further, an indirect feed quantity of fuel, said fuel being to evaporate from an adhered liquid layer of fuel in an intake port and then to be fed into the combustion chamber, is calculated as the sum of plural partial feed quantities of different evaporation characteristics.

Abstract: A method of fabricating a thin-film magnetic in which a mask pattern in etching a bottom pole is formed of first and second mask films in this order when viewed from the bottom pole, the first mask film is used for defining, by self-alignment, the length of that portion of the side edge of a top pole which is nearly perpendicular to a magnetic gap, the second mask film makes it possible to etch the bottom pole with high dimensional accuracy, a non-magnetic film is formed on the mask pattern having the bottom pole thereunder and the exposed region of a substrate, and the top pole is formed after the mask pattern has been exposed and removed.

Abstract: An engine control method in which a valve drive mechanism and a fuel injection device are controlled by an electronic control unit during transition between a cylinder-off state and a cylinder-on state of a variable-cylinder engine. During transition from the cylinder-on state to the cylinder-off state, the operation of a suction valve and an exhaust valve is stopped when at least one suction stroke is executed after the stoppage of fuel injection. When the operating state is restored from the cylinder-off state to the cylinder-on state, on the other hand, normal combustion is effected immediately after the valve operation is restarted following preliminary fuel injection if the engine is in a rapid-acceleration operation region. In a normal operation mode, the fuel injection is started after the valve operation is restarted.

Abstract: A thin film magnetic head comprising a substrate on which are successively formed a base layer, a lower magnetic film, a gap layer, an insulator layer, a conductor coil, an upper magnetic film, and a first mask, is manufactured by a method in which one or more of a gas which can be expressed by the general formula of CnHxFy (where n.gtoreq.1, x+y=2n+2, x>0, y>0, and x.gtoreq.y); and a gas which can be expressed by the general formula of CnHxFy (where n.gtoreq.1, x+y=2n+2, x.gtoreq.0, y.gtoreq.0, and x<y) is used. The structure of the magnetic head thus obtained is such that, at a height near the interface between the mask and the upper magnetic film provided therebelow, the angle defined by the side edge surfaces of the mask and the above-mentioned interface ranges from 75.degree. to 90.degree..

Abstract: A magnetic disc apparatus includes a magnetic disc for recording information; a thin film magnetic head including a magnetic pole structure having an upper magnetic pole tip and a lower magnetic pole tip arranged to provide a magnetic gap at respective end portions thereof for writing and reading information in and from the magnetic disc; a device for rotating the magnetic disc; and a device for positioning the thin film magnetic head; the upper and lower magnetic pole tips having different contours at the respective end portions as viewed from a side confronting the magnetic disc wherein the difference (.DELTA.CW in .mu.m) in the width, along the magnetic gap, of the upper magnetic pole tip and the width, along the magnetic gap, of the lower magnetic pole tip satisfies the relation0<.DELTA.CW.ltoreq.5000/Trfor the magnetic disc having a track density Tr of 1800 or more tracks per inch.