Abstract: A variable-gain circuit includes an amplifying transistor, a first gain control section for receiving a first gain control signal to control the amplifying transistor to have a first gain curve of decibel gain convex toward the bottom of graph, and a second gain control section for receiving a second control signal to control the first transistor to have a second gain curve of decibel gain convex toward the top of graph. The first and second control signals are fed at a time to cancel the non-linearity of the gain curves to have an overall linear gain curve.

Abstract: N-[N-[3-(3-hydroxy-4-methoxyphenyl)propyl]-L-&agr;-aspartyl]-L-phenylalanine 1-methyl ester useful as a sweetener with a high potency of sweetness, is provided in the crystalline form having a high stability and a good purity which is favorable as a commercial product.

Abstract: The present invention relates to a method of manufacturing aspartyl dipeptide ester compounds, which can be used as sweeteners, and aldehydes that can be used in the manufacturing processes.

Abstract: There is disclosed a variable-gain amplifier circuit comprising an adjustable impedance circuit part including a bipolar transistor having a base connected to a control terminal for receiving a controlled bias voltage, a collector connected to a positive power supply voltage terminal, and an emitter connected to ground through a diode in such a manner that an anode of the diode is connected to the emitter of the transistor and a cathode of the diode is connected to the ground. The variable-gain amplifier circuit further comprises a variable-gain amplifying circuit part having an amplifying circuit having an input coupled through an DC blocking capacitor to an input terminal for receiving an input signal and an output connected to an output terminal. The emitter of the bipolar transistor is connected to a node between the input terminal and the DC blocking capacitor.

Abstract: N-[N-[3-(2-hydroxy-substituted phenyl)propyl]-L-&agr;-aspartyl]-L-phenylalanine 1-methyl ester derivatives, which are useful as sweeteners, may be conveniently produced by subjecting a 2-hydroxychroman derivative having various substituents on the benzene ring and aspartame to a reductive alkylation reaction. These compounds may be purified by subjecting such a derivative containing one or more impurities to a crystallization step to crystallize the same.

Abstract: An inexpensive mechanical fuse having a high fatigue limit ratio and high rupture reliability, and superior in forming performance, and a method of manufacturing the same are presented. The mechanical fuse is composed of Fe-based sintered alloy, and comprises an inner rim 2 fixed to one power transmission shaft, an outer rim 3 fixed to the other power transmission shaft, and plural arms 4 for linking the inner rim 2 and outer rim 3, which are formed integrally. The arms 4 include rupture portions 6 which are ruptured when exposed to an overload torque. By treating in steam, an iron oxide phase is formed in the surface layer and pore inner wall. The iron oxide phase is effective to form round pores and lower the notch sensitivity. As a result, the fatigue strength and fatigue limit ratio are enhanced.

Abstract: A friction clutch such as an electromagnetic clutch, in which a driving friction surface is formed on a rotor integral with a rotationally driven pulley and a driven friction surface in opposed relation to the driving friction surface is formed on an intermediate member pivotally mounted on a boss by a pin, is disclosed. When the rotor is in rotation, the armature portion of the intermediate member is attracted by an initial energizing means for generating a comparatively small force such as an electromagnetic coil so that the intermediate member is rotated around the pin. When the friction surface of the intermediate member is lightly pressed against the friction surface of the rotor, the friction force exerted tangentially to the contact surface causes the intermediate member to rotate further around the pin and generate a large force along the normal. Thus, the friction force is increased thereby making it possible to transmit a large power from the rotor to the boss through the intermediate member.

Abstract: A torque limiting mechanism includes an axial space formed in a cylindrical wall of a pulley, and a pin protruding and extending from a back surface of a discharge disc. The pin is inserted into the axial space, and a rubber damper is installed between the inner surface of the axial space and the pin. When torque difference between the pulley and the discharge disc exceeds a threshold, a root portion of the pin is broken to separate the discharge disc from the pulley, thereby interrupting rotation transmission from the pulley to the discharge disc.

Abstract: A variable-gain circuit includes an amplifying transistor, a first gain control section for receiving a first gain control signal to control the amplifying transistor to have a first gain curve of decibel gain convex toward the bottom of graph, and a second gain control section for receiving a second control signal to control the first transistor to have a second gain curve of decibel gain convex toward the top of graph. The first and second control signals are fed at a time to cancel the non-linearity of the gain curves to have an overall linear gain curve.

Abstract: An electromagnetic coil is fixed in a rotor through an insulation member. A slip-ring rotating with a rotor and a brush supplying electric current to the slip-ring are disposed radially inside a boss portion of a compressor housing. The slip ring is attached to the rotor through a slip-ring supporter, and the brush is supported by the boss portion through a brush supporter. The brush supporter includes a cylindrical sleeve radially inside the brush, which extends axially outwardly farther than a slide surface between the slip-ring and the brush.

Abstract: The present invention provides an acetone adduct of V-28-3M to be used as an intermediate for producing V-28-3M which is useful as a fungicide, a process for producing it and a process for purifying V-28-3M. When crude V-28-3M is dissolved in acetone, an acetone adduct of V-28-3M is to remarkably improve the crystallization rate and, accordingly, also to remarkably improve the purity. The obtained acetone adduct can be easily hydrolyzed to obtain pure V-28-3M.

Abstract: An electromagnetic coil is disposed in a rotor, and electrically insulated from the rotor. A slip-ring is supported by a rotor through a slip-ring supporter, and rotates with the rotor. A brush is supported by a compressor boss portion through a brush supporter, and supplies an electric current to the slip-ring. A diode is disposed in the brush supporter or the slip-ring supporter, and absorbs a surge voltage which is inducted when said electromagnetic coil is disenergized.

Abstract: An electromagnetic clutch has an armature, a rotor housing accommodating a stator housing and an exciting coil having negative and positive terminals. A passage is formed to extend from an outer peripheral surface of the stator housing to the negative terminal and the positive terminal. The passage is filled with a conductive metal member having a melting point lower than that of the stator housing between the outer surface of the stator housing and the negative terminal. When frictional heat generated between the armature and the rotor housing exceeds a preset value, the metal member melts and flows to the positive terminal, thereby short-circuiting the coil. As a result, a fuse between a power source and the clutch is fused, thereby turning off the clutch. Therefore, the clutch does not need to have a thermal fuse therein and is reduced in size without increasing power consumption.

Abstract: A power transmission apparatus which can function as a torque limiter during an overload condition. A Belleville spring is provided for generating mutual frictional engagement in areas between a flange part integral to an inner holder member, a washer, arc shaped projections of a flange part of a hub and a washer. As a result, during a normal condition of a compressor, the rotating movement of the inner holder member located adjacent to the rotating movement source is transmitted via the frictional engagement mechanism to a hub and then to a rotating shaft. Contrary to this, during an overloaded condition, a slippage is generated in the area between the washer and the arc shaped projections of the flange part of the hub as a frictional engaging area of a lower coefficient of friction.

Abstract: In order to reduce its size of a coil-rotation type electromagnetic clutch in an axial direction and to prolong the life of its brush, a sliding current supply mechanism, which has slip rings and slidable brushes which contact the slip rings, is located inside an inner circumference of a housing boss of a compressor. The current is supplied to an electromagnetic coil via the sliding current supply mechanism. Since the sliding current supply mechanism is located in the boss, a current supply passage is formed without increasing the size of the clutch in axial direction. Thus the installation of the electromagnetic clutch in the engine room is facilitated. Furthermore, since the sliding current supply mechanism is located near the rotational center of the clutch, the life of the brush is prolonged due to the small peripheral velocity of the brush.

Abstract: In order to improve the magnetic efficiency and the assembling productivity of a coil-rotation type electromagnetic clutch, an electromagnetic coil is located in a ring-shaped recess of a rotor, and friction surfaces facing an armature are formed on both ends of an inner cylindrical portion and an outer cylindrical portion. A friction plate is located in the recess and closer to the armature than the electromagnetic coil. A magnetic shield is located at a place corresponding to the middle of the friction plate in the radial direction. The friction plate is fixed to the ends of the inner cylindrical portion and the outer cylindrical portion by securing protrusions of the friction plate to grooves formed on the inner cylindrical portion and the outer cylindrical portion.