Control Means Responsive To Sensed Condition Patents (Class 414/699)
  • Patent number: 5822891
    Abstract: A work area limitation control system for a construction machine which includes a second entrance forbidden area calculating portion which sets a second entrance forbidden area positioned closer to a front device than a first entrance forbidden area. A slowdown control calculating portion calculates distances between two monitoring points and the second and first entrance forbidden areas and modifies operation signals (pilot pressures) depending on the relation of the calculated distances with respect to a slowdown distance.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: October 20, 1998
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Kazuo Fujishima, Hiroshi Watanabe, Masakazu Haga
  • Patent number: 5782018
    Abstract: A method and a device to control a bucket actuator, which controls the scooping, carrying, scraping, or digging action of the bucket, automatically switches between a bucket angle-maintaining control mode and a manual operation mode. The bucket angle-maintaining control mode, which automatically maintains a bucket angle, is used when the method determines that excavating is not being performed. The method automatically switches to the manual operation mode when the method determines, from the two parameters of bucket angle and stick movement, that excavating is being performed.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: July 21, 1998
    Assignee: Shin Caterpillar Mitsubishi Ltd.
    Inventors: Shoji Tozawa, Tomoaki Ono
  • Patent number: 5748097
    Abstract: A method and apparatus is disclosed for storing a boom pivotally mounted to a vehicle. The apparatus includes a boom actuator to actuate the boom, a boom sensor to provide a boom signal representative of the position of the boom actuator with respect to a stable reference point and an actuator control assembly responsive to a control signal to manipulate the position of the boom by retracting or extending the boom cylinder. The apparatus also includes a controller responsive to the boom signal and to provide the control signal to the actuator control assembly so the boom is automatically driven from an initial position extended at least partially away from the vehicle to a transport position in a relatively closer proximity to the vehicle by retracting the boom cylinder to drive the boom from the initial position to a transition position and then extending the boom cylinder to drive the boom from the transition position into the transport position.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: May 5, 1998
    Assignee: Case Corporation
    Inventor: David L. Collins
  • Patent number: 5735066
    Abstract: A construction machinery having a first boom 1 rotatably mounted on a vehicle frame, a second boom 4 rotatably mounted on the first boom 1, a first boom cylinder 2 connecting the vehicle frame 3 and the second boom 4, and a second boom cylinder 5 connecting the second boom 4 and the first boom 1, characterized in that it is arranged in such a way that the drive of the working machines in the new link mechanism is controlled simply and with high precision by indicating the position or the velocity of the working machine leading end by subjecting a working machine leading end target value to coordinate conversion to the target angles for the first and second boom angles, determining the target cylinder length for the first boom cylinder 2 from the target angles for the first and second boom angles obtained by the coordinate conversion, and driving the first boom cylinder 2 according to the target cylinder length.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: April 7, 1998
    Assignee: Komatsu Ltd.
    Inventors: Mamoru Tochizawa, Atsushi Nagira
  • Patent number: 5735065
    Abstract: In an area limiting excavation control system for construction machines such as hydraulic excavators, excavation is smoothly and efficiently carried out within a limited area by setting an area beforehand where a front attachment (1A) is movable, calculating the position and posture of the front-attachment (1A) by a control unit (9) based on signals from angle sensors (8a) to (8c), calculating a limit value of the component of the boom-dependent bucket tip speed vertical to the boundary of the set area so that when the front attachment is inside the set area near the boundary thereof, the moving speed of the front attachment in the direction vertical to the boundary of the set area is restricted, and when the front attachment is outside the set area, it is returned to the set area, and modifying a boom operation signal so as to prevent the boom-dependent bucket tip speed from exceeding the limit value.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: April 7, 1998
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Eiji Yamagata, Kazuo Fujishima, Hiroyuki Adachi, Hiroshi Watanabe, Masakazu Haga
  • Patent number: 5713144
    Abstract: A linear excavation control apparatus for a hydraulic power shovel has a laser oscillator installed on the surface of a target area of excavation, a laser beam receiving unit mounted upon a vehicle body of the hydraulic power shovel and a controller for controlling an attitude of excavation by a bucket. The inclination of the laser beam receiving unit and the attitude of excavation of the bucket can be adjusted.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: February 3, 1998
    Assignee: Komatsu Ltd.
    Inventor: Yoshinao Haraoka
  • Patent number: 5704429
    Abstract: A control system of an excavator. The excavator includes a lower running body, an upper pivoting body, a working device having a plurality of links attached to the upper pivoting body, a pivoting device, and a running device, actuators for actuating the working device, the pivoting device, and the running device, hydraulic control valves for controlling quantities of hydraulic fluid supplied to the actuators, sensors for detecting relative angular positions of the links, and a control system.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: January 6, 1998
    Assignee: Samsung Heavy Industries Co., Ltd.
    Inventors: Jin Han Lee, Jeong Chul Lee
  • Patent number: 5704141
    Abstract: A backhoe having a swivel deck supporting a driver's section and a hydraulically operable boom assembly. This backhoe includes a detecting device for detecting a position, direction of movement and velocity of movement of a bucket relative to the driver's section, and a control device for controlling the boom assembly based on detection values provided by the detecting device. The control device has a function to prohibit operation of the bucket when the bucket moves inwardly of a danger plane A1 or A2 disposed at a predetermined distance outwardly of the driver's section. The control device establishes a caution plane C1 or C2 disposed at a predetermined distance outwardly of the danger plane A1 or A2, and has a time estimating function which, when a bucket pin 6a lies in a danger zone B1 or B2 defined by the danger plane and caution plane, computes and estimates time taken for the bucket 6 to reach the danger plane A1 or A2.
    Type: Grant
    Filed: October 26, 1995
    Date of Patent: January 6, 1998
    Assignee: Kubota Corporation
    Inventors: Keisuke Miura, Eiji Nishi
  • Patent number: 5701691
    Abstract: In an excavation area limiting control system for a construction machine for limitingly controlling an area to be excavated, a region where a front device 1A is movable is set beforehand. The position and posture of the front device are calculated based on signals from angle sensors 8a-8c, and a target speed vector of the front device is calculated based on detection signals from control lever units and load pressures detected by pressure sensors 270a to 271b. The target speed vector is modified so that a vector component of the target speed vector in the direction toward the boundary of the set region is reduced when the front device is within the set region near the boundary thereof, and the front device is returned to the set region when the front device is outside the set region. Control signals corresponding to the modified target speed vector are further modified depending on the load pressures and output to proportional solenoid valves 210a to 211b.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: December 30, 1997
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hiroshi Watanabe, Toichi Hirata, Masakazu Haga, Eiji Yamagata, Kazuo Fujishima, Hiroyuki Adachi
  • Patent number: 5699247
    Abstract: A system for controlling the cutting operation of a hydraulic backhoe having a bucket pivotally joined to one end of an arm, the other end of which is pivotally joined to one end of a boom having another end pivotally supported on a self propelled vehicle. Hydraulic jacks are provided for pivoting the boom relative to the vehicle, the arm relative to the boom, and the bucket relative to the arm. During each cutting operation the actual bucket speed relative to the arm and the actual arm speed relative to the boom are sensed and referred to a set of fuzzy control rules for obtaining command values for controlling the boom, arm and bucket jacks. The fuzzy control rules are so determined and utilized as to enable the machine to automatically take a cut in a manner suiting the hardness or other characteristics of the soil.
    Type: Grant
    Filed: July 8, 1991
    Date of Patent: December 16, 1997
    Assignee: Shin Caterpillar Mitsubishi, Ltd.
    Inventors: Naoyuki Moriya, Makoto Samejima, Yujiro Shimizu
  • Patent number: 5694317
    Abstract: A blade control system for a bulldozer, comprising: (a) a pitch angle detector for detecting a pitch angle of a vehicle body when the vehicle body inclines back and forth; (b) an actual tractive force detector for detecting an actual tractive force of the vehicle body; and (c) a controller for correcting the actual tractive force detected by the actual tractive force detector according to the pitch angle detected by the pitch angle detector and for controlling the blade to be lifted or lowered such that the corrected actual tractive force becomes equal to a target tractive force.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: December 2, 1997
    Assignee: Komatsu, Ltd.
    Inventors: Hiroshi Nakagami, Shigenori Matsushita, Shigeru Yamamoto
  • Patent number: 5682311
    Abstract: A depth measuring apparatus for an excavator which includes an inclination sensor assembly mounted along the pivot axis between the stick arm boom and the bucket, a depth sensor mounted along the same pivot axis as well as a laser receiver for receiving a radiation establishing a reference level mounted coaxially with the pivot axis between the stick arm boom and the bucket such that after the reference level has been established, and the laser receiver is impinged by radiation each time it passes through the reference level, thereby zeroing out the measuring apparatus, the actual depth of a trench may be measured with respect to the reference level by considering the inclination of the bucket as well as the depth displayed by the depth sensor when the bucket is lowered into the trench.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: October 28, 1997
    Inventor: George J. Clark
  • Patent number: 5629849
    Abstract: The present invention relates to a method for automatically controlling prescribed work to be repeatedly done by the excavator. An electronic control using a processor and sensors is used to precisely control the work under program control regardless of the hardness of the ground. The controlling method according to the present invention utilizes stored data of the position of each of the joints of the actuators when the prescribed work is performed. During the repeated work, each joint is able to maintain its desired position regardless of the hardness of the ground. Further, because the operational mode can be stored at the same time as storing of the data for the prescribed work, the invention compares the operational mode with the repeated work. The performance speed of the repeated work can be controlled as much as intended by the operator. The repeated work can be performed with high speed when an unskilled operator stores the operation of the prescribed work with a slow speed.
    Type: Grant
    Filed: October 10, 1995
    Date of Patent: May 13, 1997
    Assignee: Samsung Heavy Industries Co., Ltd.
    Inventor: Seong-Ho Ahn
  • Patent number: 5621643
    Abstract: A dozing system for a bulldozer with which dozing can be carried out by a simple operation without giving a great deal of fatigue to the operator.When the running slip of a vehicle body is not detected by a running slip detector, a blade is lifted or lowered by a comparison controller such that an actual tractive force of the vehicle body detected by an actual tractive force detector becomes coincident with a target tractive force set by e.g., a dial, whereby the amount of loads applied to the blade by excavating and moving earth can be maintained constant. On the other hand, when the running slip of the vehicle body is detected by the running slip detector, the comparison controller lifts the blade, thereby reducing the amount of loads applied to the blade by excavating and moving earth in order to eliminate the running slip.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: April 15, 1997
    Assignee: Komatsu Ltd.
    Inventors: Hiroshi Nakagami, Shigenori Matsushita, Shigeru Yamamoto
  • Patent number: 5577876
    Abstract: A control apparatus controls movement of a lift arm and tool on a skid steer loader. Power actuators are coupled to the lift arm circuit and the tool circuit for moving the lift arm and tool along a path. A sensor is coupled to the skid steer loader for sensing a desired parameter and providing a signal indicative of the desired parameter. A power interrupter is coupled between the power actuators for the lift arm and tool and the sensor and interrupts power to the actuators based on the signal. A manually operable bypass mechanism is coupled to the power interrupter and the power actuators and is used to bypass the power interrupter to allow movement of the lift arm.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: November 26, 1996
    Assignee: Clark Equipment Company
    Inventors: Thomas Q. Haeder, Larry E. Albright, Orlan J. Loraas, William C. Shelbourn, Gerald M. Berg, Lyle L. Johnson, Thomas M. Sagaser, Knute K. Brock
  • Patent number: 5572809
    Abstract: An apparatus and method for controlling a hydraulically operated construction machine, having a plurality of tandem articulated members which are controlled in a manner that movement of one of the members is controlled in response to movement of another of the members, in order to move the members in a predetermined pattern. The members are controlled in response to the anticipated future movement of the another member. Anticipated future movement of the another member may be determined, for example, as a function of the present position and velocity of the another member and system delay in movement of the another member. Where the another member is controlled manually by an operator control lever coupled with a manual hydraulic control valve, anticipated future movement may be determined by monitoring actuation of the control lever.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: November 12, 1996
    Assignee: Laser Alignment, Inc.
    Inventors: Timothy E. Steenwyk, Eric J. Walstra
  • Patent number: 5493798
    Abstract: According to one aspect of the present invention, a control system for automatically controlling a work implement of an excavating machine through an excavation work cycle is provided. The work implement includes a boom, stick and bucket, each being controllably actuated by at least one respective hydraulic cylinder, the hydraulic cylinders containing pressurized hydraulic fluid. The control system includes an operator control element adapted to produce an operator control signal indicative of a desired velocity of one of the hydraulic cylinders. An electrohydraulic valve actuates predetermined ones of the hydraulic cylinders to perform an excavation work cycle in response to the control signal. A sensor produces signals indicative of the forces associated with at least one of the hydraulic cylinders.
    Type: Grant
    Filed: June 15, 1994
    Date of Patent: February 27, 1996
    Assignee: Caterpillar Inc.
    Inventors: David J. Rocke, Lonnie J. Devier, Dale B. Herget
  • Patent number: 5488787
    Abstract: When a prime mover (1) is driven, a controller (25) outputs an open-drive signal for bringing an opening/shutting valve (23) into an open position and, upon a control lever (68, etc.) being operated, a hydraulic fluid is supplied from an auxiliary hydraulic pump (7) through pressure reducing valves to driving sectors of directional control valves (8 to 16) for shifting them. A flow rate and a direction of flow of the hydraulic fluid from main hydraulic pumps (3, 4) are thereby adjusted so that actuators (57A, 57B, 57C, 56A, 54) can be each operated at a speed depending on the amount by which the control lever is operated. When one of the actuators (57A, 57B, 57C, 56A, 54) is to be driven when the prime mover (1) is not driven, an open command is selected in a selection command device (24), whereupon the controller (25) outputs the open-drive signal, causing the opening/shutting valve (23) to open a line interconnecting the accumulator (21) and the pressure reducing valve (17), etc.
    Type: Grant
    Filed: August 3, 1994
    Date of Patent: February 6, 1996
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Yukio Aoyagi, Kazuhiko Otsubo, Gen Yasuda, Koji Fujita, Takayuki Yamakawa, Kazuyoshi Narita
  • Patent number: 5479729
    Abstract: Control of a piece of excavation equipment (10) to temporarily disable it from further excavating in an area where a buried cable and/or pipe (50) is present is accomplished by providing a detector (54) for sensing if the buried cable and/or pipe is sufficiently close to be potentially damaged. The detector provides a signal indicative of the presence of the buried cable for transmission, via a transmitter-receiver pair (56, 60), to a control valve (62). When a buried cable and/or pipe is detected, the control valve is actuated to divert hydraulic oil that would otherwise flow to a cylinder (44) that provides forward movement of a bucket (38) on the excavating equipment, thereby preventing further excavation by the bucket in the region of the buried cable and/or pipe.
    Type: Grant
    Filed: April 4, 1994
    Date of Patent: January 2, 1996
    Assignee: AT&T Corp.
    Inventor: Hossein Eslambolchi
  • Patent number: 5469646
    Abstract: A hydraulic excavator adapted to be changed over simply to a fine operation mode so as to control the capacity of a hydraulic pump through load-sensing control to thereby make it possible to perform accurate work when the machine needs to be finely operated temporarily for operations such as ground levelling, and position adjustment on a dump vessel, wherein the fine operation mode is easily cleared to switch the excavator to a standard mode to thereby improve operability, as well as work efficiency. When the excavator is switched to the fine operation mode so as to control the capacity of the hydraulic pump through load-sensing control for accurate work, the engine is driven at such a torque and engine revolution as permitting a minimum fuel consumption, thus reducing the fuel consumption of the engine.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: November 28, 1995
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Fujitoshi Takamura
  • Patent number: 5467541
    Abstract: Vehicles (12) having implements (14) are typically used to perform repetitive functions in work cycles. Advantageously, such vehicles (12) include control systems (10) for maintaining a control lever (26) in a predetermined position until an associated work cycle function is completed. The subject control (10) includes a rocker bar (46) connected to the control lever (26) and a solenoid (50) having an actuator rod (52) disposed adjacent the rocker bar (46). The control (10) energizes the solenoid (50) to hold the control lever (26) in the predetermined position in response to a position of the implement (14), a position of the control lever (26), and a desired kickout position.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: November 21, 1995
    Assignee: Caterpillar Inc.
    Inventors: Robert D. Greer, Daniel E. Henderson, Javad Hosseini, Noel J. Rytter, Gerald P. Simmons
  • Patent number: 5461803
    Abstract: A control system for automatically controlling a work implement of an excavating machine through a machine work cycle is disclosed. The work implement includes a boom, stick and bucket, each being controllably actuated by at least one respective hydraulic cylinder. A position sensor produces respective position signals in response to the respective position of the boom, stick and bucket. A pressure sensor produces respective pressure signals in response to the associated hydraulic pressures associated with the boom, stick, and bucket hydraulic cylinders. A microprocessor receives the position and pressure signals, and produces a command signal. An electrohydraulic system receives the command signal and controllably actuates predetermined ones of the hydraulic cylinders to perform the work cycle.
    Type: Grant
    Filed: March 23, 1994
    Date of Patent: October 31, 1995
    Assignee: Caterpillar Inc.
    Inventor: David J. Rocke
  • Patent number: 5446980
    Abstract: A control system automatically controls a work implement of an excavating machine through a machine work cycle. The work implement includes a boom, stick and bucket, each being controllably actuated by at least one respective hydraulic cylinder. A position sensor produces respective position signals in response to the respective position of the boom, stick and bucket. A microprocessor receives the position signals, compares at least one of the boom, stick and bucket position signals to a predetermined one of a plurality of position setpoints. A pressure sensor produces respective pressure signals in response to the associated hydraulic pressures associated with the boom, stick, and bucket hydraulic cylinders. The microprocessor receives the pressure signals, and compares at least one of the boom, stick and bucket pressures to a predetermined one of a plurality of pressure setpoints.
    Type: Grant
    Filed: March 23, 1994
    Date of Patent: September 5, 1995
    Assignee: Caterpillar Inc.
    Inventor: David J. Rocke
  • Patent number: 5426874
    Abstract: In an apparatus for controlling the vertical movement of a scraper blade (18) of a bulldozer, a four-position hydraulic control valve (12), having HOLD, UP, DOWN, and FLOAT positions, maintains the scraper blade in the FLOAT condition without requiring a detent mechanism, even when the three-position operation lever (1, 51) is released with the hydraulic control valve (12) in the FLOAT position. The operation lever (1, 51), having HOLD, UP, and DOWN positions, provides electrical signals to a controller (4) for actuating the hydraulic control valve (12) with pilot pressures provided via solenoid pilot valves (6, 7). A hydraulic cylinder (19), connected to the scraper blade (18), is actuated by hydraulic oil from the hydraulic control valve (12).
    Type: Grant
    Filed: May 24, 1994
    Date of Patent: June 27, 1995
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Kazushi Nakata, Shigenori Matsushita, Shigeru Yamamoto, Shu h-uai Zhang, Satoru Nihsida
  • Patent number: 5425431
    Abstract: An apparatus controls operation of a power machine which has a frame, a seat supported by the frame, wheels supporting the frame, a drive mechanism for driving the wheels, a lift arm structure manipulated by power actuators, and a power circuit for controlling the actuators. An occupancy sensor is coupled to the power machine for providing an occupancy signal indicative of occupancy in the seat. A traction lockout mechanism locks the drive mechanism to preclude the drive mechanism from driving the wheels. A controller is coupled to the occupancy sensor, the traction lockout device and the power lockout device and controls the traction lockout device and power lockout device based upon the input from the occupancy sensor. A display is coupled to the controller for displaying the indicia indicative of an operational state based on a display output signal provided by the controller.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: June 20, 1995
    Assignee: Clark Equipment Company
    Inventors: Kenneth A. Brandt, Scott B. Jacobson, Orlan J. Loraas
  • Patent number: 5408767
    Abstract: An excavation controlling apparatus which can effect precise driving control off a dipper in accordance with an actual operation condition with a simple structure of a low cost. A dipper handle extension instruction calculation section calculates a dipper handle extension instruction signal from a difference between a moment upper limit value set by a moment limit value setting section and a working moment calculated by a working moment calculation section, and causes a dipper handle driving motor output controlling apparatus to control a sliding driving operation of a dipper handle in accordance with the dipper handle extension instruction signal. A hoisting operation instruction calculation section corrects a hoisting operation reference instruction set by a hoisting operation reference instruction setting section with the moment upper limit value and a hoisting operation instruction correction amount calculated from the working moment.
    Type: Grant
    Filed: June 21, 1993
    Date of Patent: April 25, 1995
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Hiroyoshi Hazama, Hideo Arimitsu, Kengo Nakamura
  • Patent number: 5392539
    Abstract: In a hydraulic drive system for a construction machine, first flow control mechanism includes first and second flow control valves (11a, 11b) and first interlock mechanism (54, 55) for interlocking the first and second flow control valves with first directional control mechanism (7), and second flow control mechanism includes third and fourth flow control valves (12a, 12b) and second interlock mechanism (56, 57) for interlocking the third and fourth flow control valves with second directional control mechanism (9). First pressure control mechanism includes at least first pressure control valve (13a) operated in response to a pressure signal in a valve-closing direction, and second pressure control mechanism includes only second pressure control valve (15b) operated in response to the pressure signal in a valve-closing direction.
    Type: Grant
    Filed: June 15, 1993
    Date of Patent: February 28, 1995
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Toichi Hirata, Genroku Sugiyama, Masami Ochiai
  • Patent number: 5361211
    Abstract: A control system for automatically controlling the operation of actuators of an excavator.
    Type: Grant
    Filed: October 28, 1991
    Date of Patent: November 1, 1994
    Assignee: Samsung Heavy Industries Co., Ltd.
    Inventors: Jin H. Lee, Sang C. Heo, Jang U. Jo, Jin T. Kim, Keun T. Lee, Ju K. Kim, Sang T. Jeong, Bong D. Hoang, Chan H. Lee
  • Patent number: 5347448
    Abstract: A multiprocessor system for an excavator is disclosed. The multiprocessor system has a joy stick which controls each of cylinders for a bucket, a dipper, a boom, a swing and/or traveling parts of the excavator and adjusts engine, pump and hydraulic valves by using microprocessors. As a result, performance and function of the excavator are improved.
    Type: Grant
    Filed: November 25, 1992
    Date of Patent: September 13, 1994
    Assignee: Samsung Heavy Industries Co., Ltd.
    Inventor: Sang-Yop Nam
  • Patent number: 5308219
    Abstract: An automatic actuating system for actuators of excavator. The system of this invention automatically controls the bucket which is overloaded to be free from the overloaded state thereof, the bucket to maintain an angular position with respect to the absolute line of the ground surface so as to prevent the objects contained in the bucket from being dropped, the bucket cylinder and the boom cylinder to accomplish the desired surface finishing operation by handling for the dipper cylinder, actuators to limit the operational ranges thereof, optimal quantity of hydraulic fluid flow of the main hydraulic pumps for respective actuators, and the pre-running for the actuators.
    Type: Grant
    Filed: September 23, 1991
    Date of Patent: May 3, 1994
    Assignee: Samsung Heavy Industries Co., Ltd.
    Inventors: Jin H. Lee, Jin T. Kim, Jang U. Jo, Bong D. Hoang, Ju K. Kim, Sang T. Jeong
  • Patent number: 5308220
    Abstract: The invention concerns a scoop-and-dump jack of a loader shovel or a fork of a shovel loader and comprising a piston-rod extension 46a guided in a sealed borehole of the jack cylinder-bottom 43 to achieve a dumping motion at least as rapid as the retracting motion and to permit simple assembly and maintenance of the jack, the diameter of said extension corresponding at least to that of the piston rod 46, the jack bearing-eye 50 and the jack cylinder-bottom being integrally joined by a connection member 49 extending over most of the length of advance of the piston-rod extension 46a, and the receiving space 51 for the piston-rod extension comprising a laterally open access for purposes of assembly or exchange of the guide means and seals 44, 45 in the jack cylinder-bottom.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: May 3, 1994
    Assignee: Karl Schaeff GmbH & Co., Maschinenfabrik
    Inventor: Hans Schaeff
  • Patent number: 5257177
    Abstract: Apparatus for controlling the movement of hydraulically movable work equipment that is arranged at the end of a length-adjustable and pivotable arm, along a substantially rectilinear path of movement, the work equipment being moved with the assistance of hydraulic drive units that act on the arm in dependence on input control signals that determine the path of movement. Even in the case of non-ideal control loops for the control of the drive units, it is intended that the work equipment be moved along a desired path. For that purpose, starting from an actual position of the work equipment, a sequence of desired positions in the path of movement is ascertained and the work equipment is moved from an actual position to the next desired position, the movement into the next position not being initiated until the work equipment is located in a predetermined tolerance band about the preceding position.
    Type: Grant
    Filed: September 23, 1991
    Date of Patent: October 26, 1993
    Assignee: Danfoss A/S
    Inventors: Michael Bach, Kjeld Aagaard, Torben Juul, Hans E. Fogh, Svend E. Thomsen, Helge S. Plougsgaard, John Kristensen, Bent Larsen
  • Patent number: 5209435
    Abstract: An elevated passenger car having an emergency exit feature. The passenger car is of the type supported such that there are substantially no obstructions between the underside of the car and the ground below it. The car includes a body having a passenger compartment and an opening through the body generally at one end thereof defining an exit from the passenger compartment to outside the body. An end section is pivotally mounted on the body at the one end. Fluid pressure actuated cylinders swing the end section between a closed position in which the end section closes the exit and an open position in which said exit is opened to the outside. An elevator supported by the end section in its open position lowers passengers from the elevated passenger car.
    Type: Grant
    Filed: December 6, 1991
    Date of Patent: May 11, 1993
    Assignee: Futrex, Inc.
    Inventor: Lawrence K. Edwards
  • Patent number: 5195864
    Abstract: A hydraulic system for a wheel loader having an implement arranged for elevational and tilting movements relative to a frame of the loader. The hydraulic system includes selectively operable lifting and tilting circuitry for adjusting the position of the implement and a shock absorbing mechanism arranged in combination with the lift circuitry for allowing relative movement between the implement and the frame to provide a cushioning effect which reduces pitching of the loader. To inhibit inadvertent vertical displacement of the implement, the shock absorbing mechanism is responsive to an initial lifting action of the implement. In a preferred form of the invention, the shock absorbing mechanism is responsive to hydraulic conditions indicative of imminent tilting movement of the implement thereby eliminating inadvertent vertical displacement of the implement when the implement reaches a limit of its tilting travel.
    Type: Grant
    Filed: August 28, 1991
    Date of Patent: March 23, 1993
    Assignee: Case Corporation
    Inventors: Frank J. Drake, Bruce K. Jaecks
  • Patent number: 5188502
    Abstract: Construction vehicles of the type having a pair of lift arms extending from the frame to support a work implement, have generally been restricted to operating one specific tool. The attempt to combine the operation of several different work implements has been met with severe functional restrictions since some work implements have specific requirements not found in the operation of others. In order to provide a lift arm linkage arrangement that incorporates the functional requirements necessary to operate a plurality of work implements while maintaining a simple, yet efficient construction, an electronic controller has been included in the design. The electronic controller includes a plurality of sensors that are operatively associated with the lift and tilt linkage of the lift arm arrangement. The sensors enable the electronic controller to constantly monitor the current position of the lift arms and the work implement and compare them with a programmed sequence of movements.
    Type: Grant
    Filed: December 24, 1990
    Date of Patent: February 23, 1993
    Assignee: Caterpillar, Inc.
    Inventors: Andrew J. Tonsor, Wilton E. Quant, Javad Hosseini, Michael F. Hopkins, William E. Allen
  • Patent number: 5178510
    Abstract: A technique relating to automatic excavation by a power shovel is shown. An ideal reference locus of movement of a front edge of a bucket is approximated by a plurality of points, positions of the plurality of points and postures of the bucket at these points are previously set. If the start of automatic excavation is assigned by an operation pedal or the like, the position of the front edge of the bucket at the assigned moment is made a position to start excavation.
    Type: Grant
    Filed: July 31, 1991
    Date of Patent: January 12, 1993
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Tadayuki Hanamoto, Shinji Takasugi
  • Patent number: 5160239
    Abstract: A control system is adapted to provide substantially linear movement of a work implement. The control system receives signals from at least one control lever and coordinates the movements of the work implement's appendages through coordination of hydraulic cylinders.
    Type: Grant
    Filed: September 6, 1990
    Date of Patent: November 3, 1992
    Assignee: Caterpillar Inc.
    Inventors: William E. Allen, Paul D. Anderson, Walter J. Bradbury, John M. Hadank, Richard B. League
  • Patent number: 5147172
    Abstract: Work vehicles are used to perform a variety of functions. Advantageously, such work vehicles include systems for cushioning the ride while the vehicle is travelling. The subject automatic ride control senses the speed of the vehicle and responsively activates and deactivates the ride control by respectively connecting and disconnecting an accumulator to the lift cylinder hydraulic circuit.
    Type: Grant
    Filed: September 3, 1991
    Date of Patent: September 15, 1992
    Assignee: Caterpillar Inc.
    Inventor: Javad Hosseini
  • Patent number: 5116187
    Abstract: The present invention is concerned with an automatic speed changing apparatus preferably employable for a wheel loader. The subject of the present invention is to assure that no shift-down is carried out even when braking is effected and thereby a vehicle speed is reduced when the wheel loader approaches a dump truck (operation IV) during running of the wheel loader, e.g., along V-shaped tracks as shown in FIG. 4, whereby an operation can smoothly be performed without an occurrence of falling-down of load placed on the wheel loader while preventing an operator from feeling unpleasant. To accomplish the foregoing subject, the apparatus of the present invention is constructed such that determination as to whether or not the wheel loader is approaching the dump truck (operation IV) is made based on the determination as to whether or not lift arms (1a) are raised up to perform a loading operation, and if it is found that the foregoing determination is correct, the current speed stage is maintained.
    Type: Grant
    Filed: January 5, 1990
    Date of Patent: May 26, 1992
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Masao Fukuda, Yasuo Yamazaki
  • Patent number: 5116186
    Abstract: A technique relating to automatic excavation by a power shovel is shown. An ideal reference locus of movement of a front edge of a bucket is approximated by a plurality of points, positions of the plurality of points and postures of the bucket at these points are previously set. If the start of automatic excavation is assigned by an operation pedal or the like, the position of the front edge of the bucket at the assigned moment is made a position to start excavation.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: May 26, 1992
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Tadayuki Hanamoto, Shinji Takasugi
  • Patent number: 5088020
    Abstract: Disclosed is a pivotal movement control device for a boom-equipped working machine provided with a pivotal movement control responsive to the inclined angle of a control lever and a position detector for detecting the moved position of a boom in a lateral direction. The device includes a changeover switch for changing between an automatic mode and a manual mode, an automatic target position stop control for storing a signal from the position detector as a target stop position when the changeover switch is changed from the manual mode to the automatic mode and pivotally moving the boom to the target stop position and stopping it there while reading a positional signal from the position, when the boom is at a position other than the target stop position and the control lever is operated to the side of the target stop position.
    Type: Grant
    Filed: August 14, 1989
    Date of Patent: February 11, 1992
    Assignee: Kubota Ltd.
    Inventors: Tetsuya Nishida, Yoshiyuki Katayama
  • Patent number: 5070286
    Abstract: A manipulator arm is provided for public works machines comprising two beams of equal length and a pivoting cradle connected in series. The first or command beam is rotated about the forward end thereof on the chassis of a support unit, and the cradle is pivoted in response to rotation of the command beam by means of gears and chains designed and arranged such that the cradle undergoes a linear translational movement and maintains a predetermined inclination.
    Type: Grant
    Filed: November 15, 1989
    Date of Patent: December 3, 1991
    Assignee: Laboratoire Central des Ponts et Chaussees
    Inventors: Paul Soulard, Paul Chassaing, Georges Moreau
  • Patent number: 5065326
    Abstract: A control system and method automatically controls a work implement of an excavating machine to perform a complete excavation work cycle. In performing the work cycle, the control system automatically extends the work implement down into the trench, completes a dig stroke, captures the excavated material, swings the work implement to dump, dumps the load, returns the work implement to the trench, and repeats the work cycle until a trench is excavated according to operator programmed specifications. The control system monitors the position of the work implement and the forces exerted on the work implement and controllably actuates the work implement according to predetermined position and force setpoints.
    Type: Grant
    Filed: August 17, 1989
    Date of Patent: November 12, 1991
    Assignee: Caterpillar, Inc.
    Inventor: William C. Sahm
  • Patent number: 5062264
    Abstract: An articulated arm employs a controller to generate .delta.r, .delta..THETA. and .delta.z signals for controlling the movement of the arm in r, .THETA. and z directions to product movement of an end point from an initial location along a desired path toward a desired location. The actual location is determined by sensing the relationships between the arm segments and determining the actual location of the end point. The actual location is continuously compared with the desired location represented by the r, .THETA. and z signals and, if the difference between the actual location and desired location exceeds preselected limits, the .delta.r, .delta..THETA. and .delta.z are scaled down thereby redefining the desired location to ensure that the actual arm movement does not lag an unacceptable amount relative to the desired location.
    Type: Grant
    Filed: July 24, 1990
    Date of Patent: November 5, 1991
    Assignee: The University of British Columbia
    Inventors: Real N. Frenette, Peter D. Lawrence
  • Patent number: 5062350
    Abstract: A hydraulic drive system for a civil engineering and construction machine of the present invention comprises a hydraulic pump (11, 11A), a plurality of actuators (4-6) driven by a hydraulic fluid supplied from the hydraulic pump and including an arm cylinder (5) and a boom cylinder (4), a plurality of flow control valves (12, 14, 16) for controlling flows of the hydraulic fluid supplied to the respective actuators and including an arm directional control valve (14) and a boom directional control valve (12) and a plurality of distribution compensating valves (13, 15, 17; 13A, 15A, 17A) for controlling differential pressures across the respective flow control valves, the distribution compensating valves each having a first device (13d,15d, 17d; 13e, 13f, 15e, 15f, 17e, 17f) to set a target value of the differential pressure across the associated flow control valve.
    Type: Grant
    Filed: July 12, 1990
    Date of Patent: November 5, 1991
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hideaki Tanaka, Toichi Hirata, Genroku Sugiyama, Masakazu Haga, Yusuke Kajita
  • Patent number: 5028199
    Abstract: The present invention is concerned with a working machine in the form of a construction machine including booms 2 and a bucket 4 such as a wheel loader, a shovel loader or the like. When a scooping operation is performed by alternately repeating a tilting operation with the use of only a bucket operation lever 16 while a boom operation lever 15 is held at a boom kick-out position, a lifting operation for the booms 2 and a tilting operation for the bucket 4 while the boom operation lever 15 is shifted to a neutral position, a lift speed of the booms 2 is variably controlled to a speed corresponding to a tilt speed of the bucket or an angle of the booms whereby the tilt speed is harmonized with the boom speed.
    Type: Grant
    Filed: July 6, 1990
    Date of Patent: July 2, 1991
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Masanori Ikari, Nobooru Yajima
  • Patent number: 5019761
    Abstract: A force feedback control system for a backhoe includes a single grip articulated control arm having members and joints therebetween analogous to the members and joints of an articulated backhoe arm connecting an excavation bucket to a backhoe frame. A bilateral closed loop control circuit compares slave position signals from output joint position sensors associated with the backhoe arm joints with corresponding master position signals from input joint sensors associated with the control arm joints and provides command signals to actuators associated with the backhoe joints to move them so that differences in corresponding master and slave position signals are minimized. Backhoe joint load sensors provide load signals indicating resistance to movement of the associated backhoe joints, and the control circuit generates force feedback signals to drive feedback motors associated with the control arm joints to apply toruqes thereto to reflect the resistance to movement of the associated backhoe joints.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: May 28, 1991
    Inventor: Brett W. Kraft
  • Patent number: 5000650
    Abstract: The material loading machine supported on the ground surface is in combination with a return to travel assembly. The combination includes a material loading machine chassis, a work implement, and at least one lift arm supported by the chassis to pivot between an uppermost position and a lower most position while supporting the work implement. Actuators pivotally raise and lower the lift arm. A lift arm position control system automatically stops the lift arm in an uppermost position when it is raised upwardly and automatically stops the lift arm in a return to travel position when it is lowered. In the return to travel position the work implement is located safely above the ground surface so that the vehicle may travel without scraping the work implement on the ground surface.
    Type: Grant
    Filed: May 12, 1989
    Date of Patent: March 19, 1991
    Assignee: J.I. Case Company
    Inventors: Lloyd A. Brewer, James C. Skeel, William R. Seidel
  • Patent number: 4989567
    Abstract: In a construction machine having an engine speed setting device, a throttle lever for instructing a set number of revolutions to the engine speed setting device, and plural operating levers each for instructing the operation of an actuator, an engine speed controlling system including a lever neutral detector for detecting a neutral condition of the operating levers and outputting a lever neutral signal. A positive action switch outputs a deceleration command signal when operated by an operator. A control device outputs to the engine speed setting device either a normal operation command at the set number of revolution provided by the throttle lever or a deceleration command at a small number of revolutions in accordance with the signals provided from the lever neutral detector and the switch.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: February 5, 1991
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventor: Jun Fujioka
  • Patent number: 4984956
    Abstract: The present invention is concerned with a working machine in the form of a construction machine including booms 2 and a bucket 4 such as a wheel loader, a shovel loader or the like. When a scooping operation is performed by alternately repeating a tilting operation with the use of only a bucket operation lever 16 while a boom operation lever 15 is held at a boom kick-out position, a lifting operation for the booms 2 and a tilting operation for the bucket 4 while the boom operation lever 15 is shifted to a neutral position, a lift speed of the booms 2 is variably controlled to a speed corresponding to a tile speed of the bucket or an angle of the booms whereby the tilt speed is harmonized with the boom speed.
    Type: Grant
    Filed: November 17, 1988
    Date of Patent: January 15, 1991
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Masanori Ikari, Noboru Yajima