Abstract: The present invention relates to an apparatus and a method for extending and storing a jib of a crane which make it possible to simplify the operation of changing a wire rope. The apparatus includes an end sheave (23), which is detachably attached to the front lower end of a boom (3); a rotating device, (80) for rotating a rotary bracket (30); and a link (123), which vertically rotatably connects the end sheave (23) and the front upper portion of the boom (3) and positions the end sheave (23) above and in front of the boom (3) when the rotary bracket (30) is rotated in the forward direction of the boom (3).

Abstract: The present invention relates to a movable range indicating apparatus, for a mobile crane vehicle, which can easily display a movable range of a telescopic boom end and secure safety of a crane operation. To this end, the apparatus comprises a boom length detecting means (1), a boom angle detecting means (2), a turning position detecting means (3), a load detecting means (4), an operating condition inputting means (5), a display section (9) for indicating in rectangular coordinates, and a control section (8) for performing calculation or storage, and indicates by superimposition an image of a rated operating radius (23) and an image of an end position (24) of the telescopic boom on the display section. In addition, a target point (41) of the telescopic boom end can be indicated by superimposition.

Abstract: An apparatus and a method for controlling the operation of a reach tower crane, in which a horizontal boom can safely and securely be operated or stored by one operator in the cab, and in which even if sensors are out of order, the stability of the crane can be secured. The system has a plurality of sensors for detecting a condition of an actuator (6) actuating an apparatus to operate or store a horizontal boom (5), a controller (36) for sending a control signal based on signals from the sensors, and hydraulic apparatuses for controlling various actuators in accordance with the control signal. Further, an operation lever and an operation switch are used to extend or store the horizontal boom (5).

Abstract: The present invention relates to a suspension load and tipping moment calculating apparatus for a mobile crane which can calculate a suspension load and a tipping moment with high accuracy and use an excessive load prevention load while ensuring safety. For this reason, the apparatus is provided with sensors (50, 48, 46) for detecting a boom length, a boom angle, and an axle weight of a boom derricking cylinder (26) on a second boom (28) side, and is equipped with a controller (38) for calculating a suspension load (Wa) suspended from the second boom (28) based on signals from these sensors. In addition, for calculating a tipping moment, a boom length sensor (44) and a boom angle sensor (42) on a first boom (24) side are provided.

Abstract: A vehicle body levelling device for a working vehicle having outriggers 5 provided at the front and rear of a self-propelled lower running body 1 for stabilizing the vehicle body while in service wherein the inclinations of the vehicle body in the front to rear and left to right directions thereof are detected by means of a front to rear inclination detector 13 and a left to right inclination detector 14, respectively, and the lengths of the front, rear, left and right outrigger arms 6 are detected by outrigger length detectors 18 so as to calculate by a controller 10 required amount of extension of piston rods of the left and right jack cylinders 7 provided on the front and rear outriggers 5, and wherein a control valve 15 provided on each of the jack cylinders is controlled in accordance with results of the calculation, whereby the vehicle body can be levelled in a short period of time even on an inclined place.

Abstract: A device for controlling the variable capacity motor incorporated in a hydraulic drive vehicle, wherein a control valve for reducing the oil pressure for controlling the motor is provided to pilot hydraulic piping extending from a control pump or controlling the capacity of the motor, and changeover valves are provided for performing changeover between operation and non-operation of the pressure reduction valve. The above structure serves to control the minimum capacity of the variable capacity hydraulic motor while reducing the pressure of pilot oil introduced from the control pump and, when a pressure in the main circuit exceeds a preset value, the changeover valves operate even when the pressure reduction valve is in operation so as to cancel such operation for continuously controlling the vehicle.

Abstract: A device for controlling a vehicle for loading work and equipped with a plurality of hydraulic pumps of fixed capacity for loading work and a torque converter driven from an engine, an electronic control governor for optionally selecting output characteristic in steps for controlling output of the engine, changeover valves disposed in the circuit on the downstream side of one pump for changing over the flow of pressure oil to a drain circuit in response to working oil pressure or an electric signal, a selection switch for selecting the output characteristics, a governor controller for controlling engine the output characteristic as selected by the switch, and control circuits for actuating the changeover valves in response to the position of the selection switch.

Abstract: A fully hydraulic steering system for a vehicle having a front frame and a rear frame coupled to each other by an articulating pin, the steering system coupling a steering unit operated by a wheel to steering cylinders, for turning the vehicle body. The steering system comprises: a sensor to detect a turning angle of the steering wheel; a sensor to detect an articulating angle of the vehicle body; a controller to compare outputs from these two sensors to drive a wheel position correcting solenoid valve according to the difference between the outputs; a pilot-type diverting valve to allow wheel position correcting oil to branch from a switch pump circuit to the wheel position correcting solenoid valve; and a safety valve to close a drain port of the pilot type diverting valve only when the driver performs steering with the wheel so that the pilot-type diverting valve feeds correcting oil to the wheel position correcting solenoid valve.

Abstract: A steering wheel position compensator of a fully hydraulic steering device for working vehicle, etc.

Abstract: This invention relates to a variable capacity pump controller for an industrial vehicle such as a shovel loader using a static hydraulic driving system. In a hydraulically driven vehicle equipped with a variable capacity hydraulic pump (P), the controller of the invention includes variable throttle devices (11, 13) (21, 24), (31, 35), (41, 46) which are disposed in pilot hydraulic circuits (10, 12), (20, 22), (30, 32), (40, 42) of a pump capacity control cylinder (C) for controlling the capacity hydraulic pump (P) and operate in such a manner as to change the operation speed of the pump capacity control cylinder (C) in accordance with the oil pressure of a main hydraulic circuit (S). According to this construction, the variable throttle device operates in such a manner as to open a check valve or a throttle valve in the pilot circuit of the pump capacity control cylinder when the hydraulic driving main circuit is at a high pressure.