| Patent Number |
Title Of Patent |
Date Issued |
| 4768339 |
Hydraulic drive system |
September 6, 1988 |
| A hydraulic drive system for a construction machine in which a hydraulic circuit has at least one hydraulic pump, at least first and second hydraulic actuators driven by a hydraulic fluid discharged from the pump, and at least first and second directional control valves connected to the |
| 4768155 |
Supersonic flaw detecting system |
August 30, 1988 |
| A supersonic flaw detecting system has a probe adapted to emit a supersonic wave towards an object to be inspected, a scanning device for causing a relative movement between the probe and the object in two orthogonal directions, a pulser-receiver adapted to supply pulses to the probe and |
| 4753515 |
Method for assembling flat type plastic multifiber connectors |
June 28, 1988 |
| A connector means includes a connector housing provided with a plurality of bores which is defined by a pair of plastic bases each having a plurality of hemicycle grooves each of which has an inner diameter 1 to several .mu.m larger than an outer diameter of each of the optical cables to |
| 4753158 |
Pilot hydraulic system for operating directional control valve |
June 28, 1988 |
| A pilot hydraulic system comprises a directional control valve having at least one pilot chamber for controlling the operation of a hydraulic actuator; and a pilot valve connected through a pilot line to the pilot chamber of the directional control valve for operation thereof. The pilot |
| 4735523 |
Vibratory compaction working machine |
April 5, 1988 |
| A vibratory compaction working machine has a lower travel structure and an upper swing structure mounted on the lower travel structure. The upper swing structure has a boom mounted thereon for pivotal movement by a first hydraulic cylinder, an arm mounted on the boom at its forward end f |
| 4718329 |
Control system for hydraulic circuit |
January 12, 1988 |
| A control system for a hydraulic circuit having an on-off valve interposed between the control valve and the actuator for allowing and blocking a flow of hydraulic fluid therebetween in which the control valve and on-off valves are actuated and switched in accordance with an operation si |
| 4710884 |
Device for compensating for deflection in a pliable positioning apparatus |
December 1, 1987 |
| A working structure having a support and an arm assembly pivotally connected to the support. The arm assembly includes at least two arm members pivotally connected to each other and each pivotally moved by a respective actuator. The second arm member has an external load applied to i |
| 4706932 |
Fluid control valve apparatus |
November 17, 1987 |
| A fluid control valve apparatus comprises logic valve means including a valve housing, a first valve member defined in the valve housing, and an axially movable valve body arranged in the first valve chamber, with the valve body including opposite end portions and a conical surface porti |
| 4697418 |
Control system for hydraulically-operated construction machinery |
October 6, 1987 |
| A control system for a hydraulic excavator having a prime mover, revolution number control device for the prime mover, at least one variable displacement hydraulic pump driven by the prime mover, displacement volume control device for the pump, actuators driven by pressurized fluid d |
| 4694698 |
Method of measuring factor of stress concentration by utilizing ultrasound |
September 22, 1987 |
| The present invention provides a method of measuring, by utilizing ultrasound, the factor of stress concentration at a stress-concentrated portion of a member, comprising the steps of emitting ultrasound for incidence upon the stress-concentrated portion of the member in stressed sta |
| 4691788 |
Lateral hole boring method and apparatus |
September 8, 1987 |
| A lateral hole boring method whereby a lateral hole of a desired length is formed underground by repeatedly performing the following steps. A vertical hole is prepared, and a lateral hole boring apparatus equipped with a leading auger of a smaller length than the diameter of the vertical |
| 4686440 |
Fine positioning device |
August 11, 1987 |
| A fine positioning device is constructed of a parallel flexible-beam displacement mechanism and/or a radial flexible-beam displacement mechanism. The former displacement mechanism comprises a first rigid portion rigid against forces, a second rigid portion rigid against forces, plura |
| 4674339 |
Multi-axis load sensor |
June 23, 1987 |
| A multi-axis load sensor is composed of at least one of a parallel plate structure connecting two members to each other by means of a plurality of flexible beams arranged in parallel to one another and a radial plate structure connecting the two members to each other by means of a plural |
| 4666352 |
Profile working machine |
May 19, 1987 |
| A profile working machine is equipped with a support for holding a work in place, a working tool for machining the work, and drive and control systems for controlling the relative displacements between the support and the working tool. The profile working machine is to machine the work i |
| 4644849 |
Locking apparatus of inertial mass drive hydraulic circuit system |
February 24, 1987 |
| An apparatus for locking of an inertial mass drive hydraulic circuit system having a hydraulic pump, an actuator driven by the hydraulic pump for driving a relatively large inertial mass, and a directional control valve mounted in line connecting the hydraulic pump with the actuator. An |
| 4627013 |
Load weight indicating system for load moving machine |
December 2, 1986 |
| A load weight calculating system for a load moving machine, such as a hydraulic excavator, including a support, and a front attachment pivotably supported by the support. The front attachment includes a first linkage element pivotably supported by the support, a second linkage element |
| 4606313 |
Method of and system for controlling hydraulic power system |
August 19, 1986 |
| A method of and system for controlling a hydraulic power system comprising an internal combustion engine receiving a supply of fuel from a fuel injection pump, and at least one variable displacement hydraulic pump driven by the internal combustion engine. An engine speed deviation is |
| 4595065 |
Shaft drilling rig |
June 17, 1986 |
| A shaft drilling rig with which a shaft is drilled into the earth with a turning force and thrust of drilling imparted to at least the drill bit of a drill string, down to a predetermined depth, and then a new drill string component is added to the drill string, for further drilling.The |
| 4587808 |
Control system for hydraulic circuit means |
May 13, 1986 |
| A control system for a hydraulic circuit having a variable displacement hydraulic pump, and an actuator driven by the pump, in which a pump control controls a displacement volume varying member of the pump based on an operating signal giving a command with respect to the position thereof |
| 4586330 |
Control system for hydraulic circuit apparatus |
May 6, 1986 |
| A control system for a hydraulic circuit including at least first and second variable displacement volume type hydraulic pumps, at least first and second hydraulic actuators driven by the pumps, and valves for controlling hydraulic connections between the pumps and the actuators. The |
| 4576515 |
Pipe laying apparatus |
March 18, 1986 |
| A pipe laying apparatus having an excavator for performing excavation in the earth to form a substantially horizontally extending hole, with the excavator having connected to its trailing end a leading end of at least one underground pipe at least partially located in the horizontally |
| 4571941 |
Hydraulic power system |
February 25, 1986 |
| A hydraulic power system having a variable displacement hydraulic pump, a hydraulic motor driven by the hydraulic pump for actuating a load, with the pump and motor being connected to constitute a closed hydraulic circuit. A hydraulic servo controls the displacement volume of the pump, |
| 4571122 |
Pipe laying apparatus |
February 18, 1986 |
| A pipe laying apparatus including an excavator propulsion unit located in a starting pit. The excavator includes an excavator body having a first axis, an excavating tool having a second axis and located at a forward end portion of the excavator body, and injection ports formed in the |
| 4561250 |
Hydraulic drive system having a plurality of prime movers |
December 31, 1985 |
| A hydraulic drive system including at least one hydraulic actuator, two variable displacement hydraulic pumps each connected to the hydraulic actuator to form a closed circuit therewith and connected in parallel with each other, two prime movers each driving one of the hydraulic pumps, a |
| 4558593 |
Failure detection system for hydraulic pumps |
December 17, 1985 |
| A failure detection system for hydraulic pumps each having displacement varying means. The system includes displacement command generating means for generating a command value for causing the displacement varying means of one of the pumps to be displaced a predetermined amount, sensor me |
| 4549640 |
Operation system for hoisting device |
October 29, 1985 |
| An operation system for a hoisting device having a hydraulic motor for driving the hoisting device, a clutch mechanism for connecting and disconnecting the motor and the hoisting device cylinder, a foot pedal for applying a brake to the hoisting device by the control of an operator, and |
| 4534268 |
Hydraulic fluid circuit of hydraulic shovel |
August 13, 1985 |
| A hydraulic fluid circuit of a hydraulic shovel including a first directional control valve group connected to a first hydraulic pump and including a first directional control valve and a second directional control valve respectively connected to a first hydraulic cylinder and a seco |
| 4531369 |
Flushing valve system in closed circuit hydrostatic power transmission |
July 30, 1985 |
| A flushing valve system suitable for use in a closed circuit hydrostatic transmission including a variable displacement hydraulic pump, a hydraulic actuator and two main lines. The flushing valve system includes poppet valves mounted in passages for respectively communicating the main li |
| 4528892 |
Hydraulic circuit system for construction machine |
July 16, 1985 |
| A hydraulic circuit system of a construction machine having first and second hydraulic circuit, and a bypass circuit for connecting the first and second circuits together. The first circuit includes a first hydraulic pump and a first valve group having a plurality of directional control |
| 4528813 |
Control system for hydrostatic power transmission |
July 16, 1985 |
| A control system for a hydrostatic power transmission having a variable displacement hydraulic pump (2) and a hydraulic actuator (3) connected in a closed or semi-closed circuit, wherein the displacement of the pump or the delivery thereby is adjustable in accordance with a manipulated |
| 4520626 |
Hydraulic drive system for single rod cylinder |
June 4, 1985 |
| A hydraulic drive system including a main line, a variable displacement hydraulic pump and another main line connected to a single rod cylinder in a closed hydraulic circuit, and a flushing valve having a first switching position in which one main line is communicated with a low pressure |
| 4517878 |
Shock absorbing device for hydraulic cylinder |
May 21, 1985 |
| A shock absorbing device for a hydraulic cylinder including a shock absorbing hole formed in an end wall of cylinder, a passageway having a port opening in the shock absorbing hole at its inner peripheral surface and a shock absorbing member attached to the piston and aligned with the |
| 4510750 |
Circuit pressure control system for hydrostatic power transmission |
April 16, 1985 |
| A circuit pressure control system for a hydrostatic power transmission having a variable-displacement hydraulic pump driven by a prime mover, a hydraulic actuator for actuating a load and a displacement adjusting mechanism for the hydraulic pump. The hydraulic pump and actuator are c |
| 4489805 |
Universal lever apparatus for hydraulic construction machine |
December 25, 1984 |
| A universal lever apparatus having a first rod and a second rod each for actuating an operated member, an operation lever connected to the first rod and the second rod and pivotally movable in a first direction for moving the first rod and in a second direction for moving the second rod, |
| 4489552 |
Automatic neutral point detecting system for hydraulic pump |
December 25, 1984 |
| An automatic neutral point detecting system for a hydraulic pump equipped with a displacement varying device capable of shifting both in a (+) direction and in a (-) direction and connected to at least one hydraulic actuator to form a hydraulic circuit to drive the hydraulic actuator. Th |
| 4489551 |
Failure detection system for hydraulic pump |
December 25, 1984 |
| A failure detection system for a hydraulic pump (1) having a displacement volume varying device (1a) and connected to at least one hydraulic actuator (4) to constitute a hydraulic circuit for driving the hydraulic actuator. The system includes means (7a, 7b) for sensing the discharge |
| 4484475 |
Method of measuring contact stress at contacting surfaces of abutting solid masses |
November 27, 1984 |
| A method of measuring a contact stress at contacting surfaces of solid masses of a same kind or different kinds by utilizing an ultrasonic wave, including the steps of causing an ultrasonic wave to impinge onto the contacting surfaces; comparing an acoustic wave of the ultrasonic wave |
| 4476679 |
Civil engineering and construction machinery with hydraulic drive system |
October 16, 1984 |
| A hydraulic drive system for civil engineering and construction machinery having at least one hydraulic pump driven by a prime mover, at least one hydraulic actuator connected to the hydraulic pump, and at least one hydraulic cylinder, the hydraulic actuator and hydraulic cylinder being |
| 4464898 |
Hydraulic power system |
August 14, 1984 |
| A hydraulic power system having a variable displacement hydraulic pump, a hydraulic motor driven by the hydraulic pump for actuating a load, the pump and motor being connected to constitute a closed hydraulic circuit, hydraulic servo for controlling the displacement volume of the pump, a |
| 4451893 |
Control method and control system for hydrostatic drive system |
May 29, 1984 |
| A control method and a control system for a hydrostatic drive system including a variable displacement hydraulic pump and a hydraulic actuator connected together to form a closed hydraulic fluid circuit. When the flow rate of the hydraulic pump is increased, the rate of change in the til |
| 4448269 |
Cutter head for pit-boring machine |
May 15, 1984 |
| A rotatable cutter head for a pit boring machine used in reverse circulation drilling. The cutter head has cutter arrays including rotary cutters and drag cutters and disposed radially and circumferentially spaced positions on the cutter head, the drag cutters having the cutting ends |
| 4403890 |
Method of laying pipe underground and system therefor |
September 13, 1983 |
| A method of and a system for laying a pipe underground wherein a head attached to the leading end of the pipe to be laid underground is caused to move in vibratory movement while a propelling force is exerted on the rear end of the pipe to obtain penetration of the earth by the pipe. Whi |
| 4395199 |
Control method of a system of internal combustion engine and hydraulic pump |
July 26, 1983 |
| A control method of a system for generating hydraulic power, the system including an internal combustion engine controlled by fuel injection from a fuel injection pump, and a plurality of hydraulic pumps of the variable displacement type. An engine speed deviation is obtained by calculat |
| 4369625 |
Drive system for construction machinery and method of controlling hydraulic circuit means thereo |
January 25, 1983 |
| A drive system for construction machinery in which hydraulic circuit is provided with a plurality of variable-displacement hydraulic pumps and a plurality of hydraulic actuators, each pump being connected in closed circuit to one or a plurality of the actuators via a solenoid-operated |
| 4354797 |
Front loading hydraulic excavator |
October 19, 1982 |
| An excavator including a boom pivotally moved by boom cylinders, an arm pivotally moved by an arm cylinder and a bucket pivotally moved by bucket cylinders further includes a boom detecting device detecting a pivotal displacement of the boom and producing a first pilot pressure subst |
| 4341276 |
Frame structure for construction vehicles |
July 27, 1982 |
| A track structure for a construction vehicle having a lower frame and a pair of track frames connected to the lower frame, in which a pair of beams of an elongated box shape which constitutes a part of the lower frame extends substantially horizontally crosswise of the vehicle. Each of |
| 4326736 |
Swivel joint for reverse circulation drill |
April 27, 1982 |
| A swivel joint to be located at the upper end of a drill string in reverse circulation drills to support loads occurring on the drill string, the swivel joint including a fixed outer housing, a center housing rotatably mounted in the outer housing through bearings, a hollow inner housing |
| 4317466 |
Hydraulic drive circuit for load-handling machines |
March 2, 1982 |
| A hydraulic drive circuit for a load-handling machine such as hydraulic crawler crane, shovel or the like in which the maximum output pressure of the circuit is determined by a main relief valve provided on the delivery side of a hydraulic pump. The drive circuit is capable of producing |
