Abstract: A peripheral surface of an annular shaped grinder is distributed with grinding particles. The grinding particles have a particles distribution such that the spacing between the grinding particles in the axial direction is less than 2/3 of the mean diameter of the particle and that the spacing between grinding particles in the circumferential direction is about 5-80 times of the mean particle diameter. The grinder is manufactured by a method of forming a pattern of an adhesive layer on a synthetic resin sheet, fixing the grinding particles to the patterns and laminating the sheets with fixed particles.

Abstract: A novel encoding method which facilitates handling at the time of demodulation (decoding) and is capable of further alleviating a burden imposed on a demodulation (decoding) circuit. When an input NRZ code signal is at, for instance, a logical "0" level during a given unit bit time, encoding is effected to obtain a signal having the same form as that of a CMI code such that the signal is set to a logical "1" level in correspondence with a first half of the unit bit time, and to the logical "0" level in correspondence with a second half thereof. Similarly, when the input NRZ code signal is at the logical "1" level during a given unit bit time, encoding is effected to obtain a signal such that the signal is unfailingly set to the logical "1" level during its initial bit time, and thereafter only during a bit time when the NRZ code signal is at the logical "1" level during the unit bit time, the logical "1" level and the logical "0" level are alternately repeated for each unit bit time.

Abstract: Magnetic field producers are disposed either at the leading portion of an underground excavator or at a reference position in front of the underground excavator. The magnetic field producers can be constituted by a plurality of rectangular loops disposed to run parallel to one another and to overlap one another. The rectangular loops can be individually excited sequentially or they can be simultaneously excited at different frequencies. The magnetic field produced by a magnetic field producer can be detected by a first magnetic field detector and by a second magnetic field detector disposed to the rear of the first magnetic field detector so that the inclination angle of the underground excavator can be obtained from the difference between the positions of the two detectors. A loop of a magnetic field producing cable can be covered by a non-magnetic metal member so that wear and disconnection are prevented.

Abstract: Two or more filters of different filtration particle size capabilities are arranged in a hydraulic circuit such that hydraulic oil containing contaminants is passed through the filters, either in series according to the order of the filtration particle size capability or in parallel. A sensor determines the pressure differential between the inlet and outlet of a respective filter, and a signal is provided to a contamination level indication device when the pressure differential between the inlet and outlet of a respective filter exceeds a predetermined level.

Abstract: According to the present invention, when a super-conductive thin film is formed on a substrate of a single crystal, a compound having a composition of SrNdGaO.sub.4 and a K.sub.2 NiF.sub.4 type crystal structure is used as a material employable for the substrate. Alternatively, a single crystal composed of an oxide in which Ca, La and Cr are added to the foregoing compound is used as a material employable for the substrate. Then, a super-conductive thin film composed of an oxide is formed on the substrate by employing an epitaxial growing method. Thus, the present invention makes it possible to provide a super-conductive material having an excellent property of lattice alignment, a stable and high critical superconductivity temperature and a stable critical superconductivity electric current.

Abstract: A multistep electronic cooler developed for the purpose of minimizing the incoming heat quantity generated by convective heat transfer and radiant heat transfer with a simple structure and bringing the maximum achievable cooling temperature to a level lower than that in a conventional electronic cooler of this kind at a low cost. The multistep electronic cooler according to the present invention has a plurality of base plates (3) arranged as cooling plates in tiers within a vacuum container (5), a plurality of pairs of semiconductors (2) arranged between the base plates via a plurality of electrodes (4) bonded to the base plates, and one layer, at least, or more of heat shielding members (7a, 7b, 7c) covering spaces above the base plates (3). The surfaces of the parts assembled to form the multistep electronic cooler are coated with a substance having a low thermal emissivity, for example, gold.

Abstract: An automatic travelling system for use in combination with a construction vehicle is disclosed. The automatic travelling system for use with a construction vehicle comprises a plurality of guide lines serving as a main traveling path device for a vehicle and disposed on a traveling road surface for the vehicle. The guide lines are disposed between a raw material site and raw material depots of a plant. A plurality of detectors on the vehicle detect the guide lines so as to facilitate steering of the vehicle.

Abstract: Provided with a wheeled road surface cutter comprising a front section attached thereto with steerable front wheels on both sides thereof, a rear section attached thereto with rear wheels, a pivot joint for coupling the front end of the rear section to the rear end of the front section, and a cutting device attached to the rear section on one side and substantially aligned with one of the front wheels on the same side.

Abstract: In a configuration in which electronically operated pressure control valves (31-36) are respectively connected to clutches of a two-stage transmission (3) composed of main transmissions (1st, 2nd, R, 4th, 3rd) and sub transmissions (L, H), when a downshift is effected from a present speed stage to a next speed stage with power on, the supply of oil pressure to a speed-changing clutch for the present speed stage is stopped on the basis of a speed-change command, the pressure control valve is actuated when a relative number of revolutions of the speed-changing clutch for the next speed stage becomes zero, which commences the supply of oil pressure to that speed-changing clutch, and the supply of oil pressure is gradually increased upon confirming the completion of a filling time of the speed-changing clutch. Thus discomfort owing to a speed-change shock is prevented in whatever state the amount of an accelerator operated and the state of operation of a brake are.

Abstract: In a plasma torch, the contact surface (61) between the nozzle (6) and the swirler (5), the contact surface (4b) between the swirler (5) and the insulating cylindrical body (4), the contact surface between the insulating cylindrical body (4) and the electrode (3), and the contact surface (3a) between the electrode (3) and the electrode table (2) are arranged in line from the nozzle (6) to the torch body (1). The inner diameter (d1) of the portion of insulating cylindrical body (4) positioned in contact with the flange (31) of the electrode (3) is smaller than the inner diameter (d2) of the flat surface (4b) of insulating cylindrical body (4) which is in contact with the end of swirler (5). An upper stepped chamber (65) or an upper tapered chamber (66) can be formed in the cylindrical portion (62) of the nozzle (6) above the swirler (5) which upper chamber has a diameter larger than that of the swirler (5) to permit easy removal of the swirler (5) from the cylindrical portion (62).

Abstract: A seal device for a gear pump, whose gear case (1), rotatably containing a pair of gears (2), (3) meshing with each other therein, is closed by side plates (4) at both sides thereof interposing seals (5) therebetween, wherein the seal (5) is formed of a plurality of annular parts (5.sub.1), (5.sub.2), projections 5a) formed on the annular parts (5.sub.1), (5.sub.2), a connecting part (5c) for connecting the annular parts (5.sub.1), (5.sub.2), and a notch (5d) formed on at least one side of said connecting part (5c). Thanks to a structure as above, even when a tensile force acts on the connecting part during the use of the device, cracks concentratedly develop at the notch (5d) and are prevented from developing at the other parts, whereby oil leakage can be prevented.

Abstract: A controller for a feeder which automatically feeds a work into and out of a press machine in relation to the operation of said press machine. The controller is capable of automatically setting optimum motion curve in accordance with the configurations and sizes of the press die and the work and determining whether any undue operating condition has been set. To this end, the feeder controller has a device for setting the operation start angle value and operation finish angle value in terms of the rotation angle of a crank shaft of the press machine, and computing device for determining a motion curve on the basis of the operation start and finish angle values. The feeder controller also has a device for computing allowable maximum operation stroke number of the press machine and a device for comparing this stroke number with a set stroke number for the purpose of determination as to whether motors are overloaded or not.

Abstract: A fine bubble generating apparatus aiming at reducing diameters of bubbles generated through outer surface of a hollow fiber by giving a running speed to liquid contacting the surface of the fiber without utilizing mechanical power developed by a pump or the like.

Abstract: An optical connector assembly (1) for connecting an optical fiber (9), an optical element (4) (light-emitting element or light-receiving element), and an electric circuit together. A bolt (32) of an optical fiber-mounting fitting in which the optical fiber (9) is inserted in the hole of an electic seal (32) and a bolt (31), is screwed into a threaded hole formed in a housing (2) of the plug (1) that accommodates the optical element (4) in order to couple the optical fiber (9) to the plug (1). The connection between the optical element (4) and the electric circuit is accomplished by a jack (20) and the plug (1) is provided with a lock mechanism based on a push-type lever (20), featuring improved sealing performance against water, oil, dust and dirt.

Abstract: The present invention aims to minimize the axial and radial clearance or play suppress a radial inertial movement in the pin joint connection portions of a machine operating link device. To achieve this, the present invention provides a joint connecting pin device for machine operating links adapted to change and retain the posture of the working unit of a hydraulic excavator or the like, the device comprising: thrust distributing and forming portions which are provided between end surfaces of pin boss portions on links on one side connected to a pin and opposed end surfaces of a link on the other side and which are adapted to distribute a thrust in the axial and radial directions; rigid-elastic annular members which are held by the thrust distributing and forming portions; and an axial movement device which is provided on at least one of the pin boss sections and which is adapted to impart a radial resilient force to the rigid-elastic annular members.

Abstract: A displacement controlling circuit system for a variable displacement pump, which system permits, following high or low rates of revolution of an engine for driving the pump, the displacement of the pump to be larger or smaller than a displacement determined on the basis of a difference between the pump delivery pressure and a load pressure. The displacement controlling circuit system comprises a revolution sensor (12) for detecting rates of revolution of the engine (9), and means (10, 11) for switching a load sensing valve (5) in such a manner that: when the detected rate of revolution of the engine is high, a displacement control member (2) of the variable displacement pump (1) is actuated in a displacement increasing direction; and, when the detected rate of revolution of the engine is low, the displacement control member (2) is actuated in a displacement decreasing direction.

Abstract: In a plasma arc cutter and a method of controlling the same, a rise compensating circuit (39) and a shift compensating circuit (44) both composed of a charging and discharging capacitor and a resistor are respectively inserted in parallel between an electrode-side connection (21) and a nozzle-side connection (35) and between the electrode-side connection (21) and a workpiece-side connection (34), and a diode (33) is provided on the workpiece-side connection in such a manner as to be inserted between a connecting point (36) of the nozzle-side connection and a connecting point (43) of the shift compensating circuit. A detector (31) for controlling a current is provided and a detector (32) for detecting a shift is provided on the workpiece-side connection. In addition, to effect cutting after boring, at least one plasma torch (14a) for boring and at least one plasma torch (14b) for cutting are provided.

Abstract: An operating lever device constructed such that the members thereof having a comparatively high rigidity can be used in such a way as to minimize the wear-down thereof and enable the angle of inclination of the lever to be detected precisely over a long period of time. The operating lever device is arranged such that any one of a plurality of rod members (22) which are inserted slidably while they are constantly urged upward into the device body (10) can be pushed down by the tilting of a lever (20) so as to rotate either a first shaft (23) or a second shaft (24) through a retaining member (27) or (28) held in contact with the lower end of the rod member (22). Thus, the angle of inclination of the lever (20) can be detected precisely by either one of rotational angle sensors (25, 26) mounted on at least one end of each of the first and second shafts.

Abstract: A hydraulic actuator is operated using a manual operation device, operations from the manual operation device are stored in the path of an operation signal to a valve controller and these are read out as required and operations similar to those from the manual operation device are outputted to the hydraulic actuator so that repeated operations of the hydraulic actuator are performed automatically. Further, a vibration signal to the hydraulic actuator is added to the operation by the manual operation device and outputted so that operation that is not accurately performed by manual operation is made possible. In the case where repeated operations are performed continuously, a correction operation by the manual operation device is taken into account so that a correction operation which is varied every given amount is made simple. Thus, the present invention can be used where the digging process of a construction machine is made deeper every given amount.

Abstract: An injection and compression molding apparatus and a method include the steps of supplying molten resin by injecting it into a cavity formed by molds and compressing the resin by applying pressure. In consideration of problems with respect to the occurrence of sink marks in molded products and the deterioration in precision which are caused by the escape of resin during compression and a change in the cavity distance between two molds, an injection and compression molding apparatus and a molding method therefor are capable of resolving the problems and stably producing molded products with good productivity. A gate is closed during compression, and a supplemental amount of resin can be injected after the compression step so as to supply the desired amount of resin in the molded article.