Abstract: A multiple valve includes first and second valve units respectively having first and second valve bodies. The first and second valve bodies have respective spool bores therein; and a respective spool is inserted in the spool bore of each of the first and second valve bodies. The first and second valve bodies of the first and second valve units also have inlet ports, tank ports, and first and second blocks having mounting holes, the blocks and a respective valve body being fixedly coupled together by means of stud bolts. The first block has a first threaded hole on one side surface thereof for receiving the stud bolt, and a second threaded hole on another side surface thereof for receiving a cover bolt. A pump passage, a main passage and a tank passage extend between the one side surface and the another side surface of the first block, and a stud bolt extends through the second block and is engaged with the first threaded hole.
November 3, 1995
Date of Patent:
April 22, 1997
Kabushiki Kaisha Komatsu Seisakusho
Masamitsu Takeuchi, Kazunori Ikei, Tadao Karakama, Mitsumasa Akashi, Teruo Akiyama, Jun Maruyama, Keisuke Taka
Abstract: A target engine revolution speed is calculated based on the throttle position of an engine such that the amount of change in the target engine revolution speed with respect to time is limited. According to the target engine revolution speed thus calculated, a target motor speed ratio, which is a target value for the ratio of the revolution speed of a motor in a hydrostatic transmission unit to the revolution speed of the engine, is set. With this target motor speed ratio, the angle of at least either of discharge controlling swash plates is adjusted.
Abstract: This invention aims at providing a glass package type capacitive element having a high reliability and a high resistance to heat and mechanical impact. In the glass package, a semiconductor device (2) is connected with a lead (5) through a conductor (8) having a bent structure.
Abstract: A self-propelling crushing machine is constructed by mounting a hopper (11) and a crusher (8) connected to said hopper on a vehicle body (1) having a traveling device (19), wherein a bottom plate (51) of said hopper (11) is designed for reciprocal motion in a horizontal direction relative to a charge inlet (8b) of said crusher. The bottom plate (51) receives an object of crush and then feeds into the charge inlet (8b) of the crusher (8) by reciprocal motion of the bottom plate to drop into the latter. Therefore, even when the weight of the object of crush or the charge amount of the object of crush into the hopper fluctuates, a substantially constant amount of object of crush can be fed into the crusher.
Abstract: An operating valve assembly with a pressure compensation valve, comprises a spool for selectively establishing and blocking communication between a pump port, an output port and a main tank port, being disposed within a spool bore of a valve body, and a pressure compensation valve being provided between the output port and the actuator port. The pressure compensation valve has a piston pressed in the closing side by a load pressure acting on a compensation pressure acting portion, and a valve provided integrally with the piston for selectively establishing and blocking communication between the output port and the actuator port, and actuated for opening by the output port pressure acting on a portion to be compensated, the compensation acting area being equal to the area to be compensated.
Abstract: A turning speed control system for use in a track-laying vehicle comprising: a steering motor for driving crawler belts provided at both sides of the vehicle such that a relative travel difference is caused between the crawler belts, thereby turning the vehicle to the right or left; a steering instructing device which can be displaced from a neutral position by operation and which instructs, according to the direction and distance of its displacement, a turning direction and a turning radius for the vehicle, the turning radius decreasing as the displacement distance increases; a displacement detector for detecting the displacement of the steering instructing device; and a control unit for performing a control such that when making the turning radius of the vehicle small by increasing the revolution speed of the steering motor according to the displacement of the steering instructing device detected by the displacement detector such that the crawler belts are driven with a relative travel difference therebetwe
Abstract: When a longitudinal straight traveling mode position A, an oblique traveling mode position B, a transverse traveling mode position C, or spin turning mode position D is selected by a traveling mode changeover switch 21, a signal corresponding to the selection is input to a controller 27. The controller outputs signals to turning actuators 15a and 15b for orienting driving wheels 11a and 11b toward the selected position. With this signal, the turning actuators 15a and 15b causes turning of the driving wheels 11a and 11b. At the same time, turning angle detection sensors 16a and 16b input signals indicative of turning angle of the driving wheels. When the turning angle becomes coincident with a preliminarily set angle, a signal for terminating turning is output to the turning actuators 15a and 15b. By this control, turning action of the turning actuators 15a and 15b is terminated with setting the driving wheels 11a and 11b at the position of the selected orientation.
Abstract: An engine overrun preventing system for a vehicle, in which the overrun of an engine is prevented when the overrun of the engine is detected, by (i) switching a lock-up system provided in a torque convertor OFF to cause a slip, if it is detected that the lock-up system is in its ON state; (ii) shifting a transmission into a speed range which is one grade lower than a presently selected speed range and reducing vehicle speed by engine brake, if it is detected that the lock-up system is in its OFF state and that the transmission is placed in another speed range than a first speed; and (iii) actuating a brake to reduce vehicle speed, if it is detected that the lock-up system is in its OFF state and that the transmission is placed in the first speed and if a detected vehicle speed is equal to a predetermined vehicle speed or more.
Abstract: A turning-purpose hydraulic circuit characterized in that a discharge passage (20a) of a hydraulic pump (20) is connected to a variable relief valve (21) and a pump port of a directional switching valve (22); a first actuator port and a second actuator port (25, 26) of the said directional switching valve are connected to a turning-purpose hydraulic motor (27); the pilot pressure of a pilot valve (33) is introduced into pressure chambers (31, 32) for controlling a spool in the said directional switching valve and is also introduced into a pressure chamber (40) for controlling a set pressure in the said variable relief valve; a metering-in side portion (42) along which a pressurized oil flows from the said pump port of the said spool to the first or second actuator port is formed with a portion having a configuration such that a flow force may not be produced thereat; and a metering-out side portion (45) along which the pressurized oil flows from the first or second actuator port of the said spool to a tank po
Abstract: The present invention is concerned with an apparatus for controlling a straight excavating operation with a hydraulic excavator such as a power shovel or the like machine including three working units, i.e., a boom, an arm and a bucket. When the straight excavating operation is performed, a hydraulic pressure of hydraulic oil in a hydraulic chamber on the boom lowering side of a boom cylinder is conducted to a drain tank while maintaining a predetermined set pressure, and a hydraulic pressure of hydraulic oil in a hydraulic chamber on the boom raising side of the boom cylinder is conducted to the drain tank via a check valve which serves to inhibit the hydraulic oil from flowing from the hydraulic chamber on the boom raising side of the boom cylinder to the drain tank, whereby the boom is held in the so-called floated state so as to enable a straight excavating operation to be performed merely by actuating the arm and bucket.
Abstract: There is provided a coupling joint for coupling a shaft (23) to a rotary axis (25a) of a rotary angle sensor (25) mounted on a valve body. The coupling joint includes an engagement recess portion (40) formed on the shaft, a coupling member (41) engageable with the engagement recess portion, and a projection (42) formed on the rotary shaft for engagement with an angular hole (45) of the coupling member. Also, the coupling member is constructed by a pair of first opposing sides (43) and a pair of second, wave-form or zig-zag opposing sides (44) forming a configuration having an angular opening. The pair of first sides are formed to fit into the engagement recess portion of the shaft. The projection fits between the pair of second sides.
Abstract: A metal particle detecting sensor (10), having a simple structure, can perform in-line analysis for metal particles in fluid and also can precisely estimate or detect the number of metal particles for each particle size. Metal films (1) and insulating films (2) are alternately laminated one upon another, and every other metal film (1) in the laminate is connected in parallel with one another to one of two lead wires (3a, 3b) so as to form comb electrodes in the laminate of the sensor, and one end face of the laminate is immersed in a fluid (4) containing metal particles so as to detect the metal particles.
Abstract: A diesel engine piston, which exhibits high resistance to heat load, has a cooling cavity formed circumferentially around and outwardly of the outer periphery of a reentrant combustion chamber. A cooling liquid inlet passageway through which cooling liquid is supplied is provided in the piston body. The inside diameter of the cooling cavity is smaller adjacent to the top of the piston than adjacent to the bottom of the piston, and the cross-sectional area of the cooling cavity gradually increases from the bottom of the cooling cavity toward the top of the cooling cavity. A funnel wall, which projects downwardly toward the bottom of the piston, serves as the inlet of the cooling liquid inlet passageway. A distributing member, positioned within the cooling cavity directly above the outlet of the cooling liquid inlet passageway, splits the cooling liquid into two streams for passage in opposite directions through two segments of the cooling cavity.
Abstract: For die arrangement, bar code tags which correspond to identification numbers given to a punch and die to be attached to a punch press are read by a bar code reader, and die information on the punch and die as well as die assembly information on a die assembly in which the punch and die are paired for pressing operation are stored in a non-volatile memory. In connection with the die assembly information, the address of the die assembly stocked in the punch press is stored. When starting pressing operation, the die assembly is fetched according to the die assembly information to perform die replacement.
Abstract: A narrow-band excimer laser employing a diffraction grating as a wavelength selective element, which is particularly suited for a light source of a reduction projection aligner. The grating used in the narrow-band excimer laser of the invention is so disposed that the ruling direction of the grating is nearly perpendicular to the direction of laser discharge. When a beam expander is used to expand laser beam falling on the beam expander is so disposed that the direction of beam expansion is nearly perpendicular to that of discharge of the laser. Further, when an aperture is to be used in the laser cavity, the aperture is placed so that the longitudinal direction may be parallel to the direction of laser discharge. Moreover, the front mirror of the laser cavity is a cylindrical one, whose mechanical axis is in parallel with the direction of laser discharge. This makes it possible to provide a narrow-band excimer laser having very high efficiency and excellent durability.
Abstract: A plasma torch, capable of cutting in a dross free state, is made possible by increased energy density of the arc jet. The operation efficiency is not reduced even with a low operating gas flow rate, since the arc jet can be stably maintained in the plasma torch. The torch has a high double arc resistance and excellent durability. This is realized by forming a velocity reduction space N from near a lower end (3b) of the electrode (3) to a nozzle (9) at the front end of the plasma torch (1), the velocity reduction space being used for reducing the axial velocity component of the operating gas which flows along the outer periphery of an electrode (3). The velocity reduction space (N) is cylindrically shaped, and the diameter (Dd) of the cylindrical shape is larger than the diameter (da) of a lower end (3b) of the electrode (3).
Abstract: A movable backing system enables it to continuously, easily perform full penetration welding along a weld line in a confined space, irrespective of the length, configuration and other factors of a weld zone. A weld backing, which has a backing member disposed on the side facing a workpiece and cooling means disposed inside the weld backing for cooling the backing member, is so supported on a wheeled carriage as to be movable toward the workpiece. The weld backing is provided with follower elements which are always in contact with the underside of the workpiece and which turn following the movement of the workpiece to keep a predetermined gap between the underside of the workpiece and the weld backing so that desired bead thickness can be obtained. The wheeled carriage is moved synchronously with the movement of the welder to continuously perform full penetration welding.
Abstract: The thermal load on a transmission clutch, which is generated when a shift between forward and reverse is made, can be reduced and a shock from a speed change can be eliminated. To these ends, as soon as a speed change signal is received (step 150), an all clutch control system (ACC) is actuated to set a target acceleration in terms of the amount of control (steps 152, 154). Then, it is determined whether the speed change involves a shift between forward and reverse (FR speed change) (step 156). If the speed change is found to be the FR speed change, then it is further determined whether the vehicle speed V is larger than a reference value V.sub.O (step 158); if the vehicle speed is larger than the reference value, then the oil pressure for operating a steering brake is read from preestablished map data (step 160), and the steering brake is operated by the oil pressure which has been read (steps 162, 164). After that, the ACC control program goes back to step 156.
Abstract: A serial controller in which nodes to which are connected one or plurality of sensors and one or a plurality of actuators are connected in series in the form of a closed loop including a main controller which sends data frame signals including a first special code, a second special code and output data for the actuators. The main controller measures and controls the time interval for sending the data frame signals and selecting a broken-line detection time setting in order to improve the transmission efficiency and to carry out the control in real time.
Abstract: A transfer press, capable of being easily transported, capable of being adjusted flexibly to changes in specifications, and capable of eliminating the idling of the transfer feeder, has a body (1) which is divided into a bed (2), uprights (3) provided vertically upon the bed, a pair of supporting beams (4) provided upon the uprights and disposed in spaced relationship with each other in a horizontal direction perpendicular to the direction in which a workpiece is fed, and a plurality of pressing units (5) each of which is independently provided for a respective one of a plurality of pressing operations. Each of the pressing units (5) comprises a crown (6) accommodating a slide-driving mechanism (8), and a slide (7). The crowns (6), provided for the individual pressing operations, are removably mounted upon the supporting beams (4). Slide guides (12) for guiding the vertical motion of the slides (7) are also provided on the supporting beams (4).