Abstract: A plasma arc can be employed to demolish a concrete structure at a high efficiency, while preventing a secondary problem due to noise, flying dust and chips, and the like. The concrete structure can be demolished by melting a surface of the concrete structure by generating a plasma arc from a plasma torch (15) of a plasma arc generator, mixing thermite powder (T) with a supply gas (Gc) for the plasma torch (15), directing the plasma arc at the surface of the concrete structure, and controlling the rate of supply of the thermite powder (T) to the plasma torch (15) in response to the operation of the plasma arc, including initiating and stopping the supply of the thermite powder (T) to the plasma torch (15) in a manner coordinated with the initiation and stoppage of the plasma arc, thereby controlling the heat generated by the thermite reaction, and melting the surface of the concrete structure.

Abstract: Upon detection of execution of operation for stopping a vehicle during its running state and of a drop in an actual speed ratio below a predetermined value, the actual speed ratio being the actual ratio of the revolution speed of an output shaft to the revolution speed of a power source, a feedback amount is determined, setting the integral component of the difference between a target motor speed ratio and an actual motor speed ratio to zero. Based on the feedback amount thus determined, an operation amount for controlling the angle of a swash plate is computed. With this amount, the angle of the swash plate is controlled.

Abstract: According to the present invention, front visibility is improved, entry into a cab or exit therefrom by an operator is facilitated, fine operability by a traveling pedal is improved, and foot fatigue is decreased. To achieve this, when the palm rest (56) is detected in its neutral position N, forward or rearward speed signals for respective traveling hydraulic motors in response to detection signals of control input detectors (19a, 20a) of left and right traveling knobs (19, 20) are outputted to respective control valves from a controller (15).

Abstract: The maximum value of target motor speed ratio is calculated from the allowable revolution speed of a motor, and based on the maximum value, an allowable value of target speed ratio is set. Target speed ratio is then limited to the allowable value or less. This enables it to prevent overrun occurring e.g., when the vehicle rolls down a hill.

Abstract: In a work support device of a camshaft miller in which a plurality of journal portions (3b) of a work (3) to be machined are supported by a plurality of supporting portions (6), (7) from a lower side and a side reverse to a work milling direction, the work support device is constructed such that supporting surfaces of the supporting portions (6) supporting the work from the lower side thereof are inclined towards the other supporting portions (7) supporting the work from the side reverse to the milling direction and wherein a clamp mechanism (10) having clamp arms (13) for pressing the work from the upper side thereof is disposed above the supporting portions.

Abstract: A speed change gear control system, wherein gear shift control for shifting the transmission from an arbitrary speed range into a higher speed range which provides higher absolute speed than the arbitrary speed range is performed, provided that the actual speed ratio e of the transmission satisfies .vertline.E.sub.1 .vertline.<.vertline.e.vertline.<.vertline.E.sub.0 .vertline. where E.sub.0 is a speed ratio for a shifting point at which the transmission is shifted from the arbitrary speed range into the higher speed range; and E.sub.1 is a specified speed ratio, or provided that .vertline.e.vertline.+(.DELTA.e/.DELTA.t).times.T.sub.1 >.vertline.E.sub.0 .vertline.-.DELTA.E.sub.1 where .DELTA.e is an increase in the speed ratio e over a period of time .DELTA.t; T.sub.1 is the filling time required for supplying hydraulic oil to a clutch which shifts the transmission from the arbitrary speed range to the higher speed range; and .DELTA.E.sub.1 is a specified small speed ratio.

Abstract: An operator cabin on construction equipment is provided with a supporting structure which improves the riding quality by absorbing and damping vibrations and large impacts transmitted to the operator cabin. The right and left side portions of a front portion of the operator cabin (1) are secured to a frame (3) of the body of the construction equipment through damper plate shock absorbers (10R, 10L) or rotatable mounts (30R, 30L), while the right and left side portions of a rear portion of the operator cabin (1) are secured to the frame (3) through spring biased hydraulic shock absorbers (20L, 20R). Each of the shock absorbers has a vibration damping function. In particular, the stroke of the spring biased hydraulic shock absorber is large enough to absorb a large impact energy. This makes it possible to absorb vibration of small amplitude. For a strong shock, the impact energy can be absorbed by oscillating the operator cabin (1) about a pivot axis through the front mounts, allowing damping of the vibration.

Abstract: A protective device for a front of a large-size dump truck, in which a driver's cab (13) is secured on a front side of a truck body (10) and a vessel (15) is, liftably from its front side, secured on a rear side of the truck body, is characterized in that a front protective guard (20) protruding forward from a position of the driver's cab is attached on a front end portion of the vessel.

Abstract: A control device for hydraulically operated machines for carrying out control to move a working unit with priority over other working units. A weight is added to each of the same manipulated amount of a plurality of operation levers 3, 4 in association with work type of M1 to M5 and the weights are stored in a memory of a controller 5 in association with the type of the operation levers 3, 4 and the work type. The work type M1 to M5 are selected by a switch 2. When the operation lever 3, 4 is manipulated and a work type is selected by the switch 2, the weight associated with the type of the manipulated operation lever 3, 4 and the selected work type M1 to M2 is read from the memory, and the read weight is added to a manipulated amount S1, S2 of the manipulated operation lever 3, 4. Then, not signals indicative of the manipulated amount S1, S2 of the operation lever 3, 4 but signals E, E' added with the weight which are indicative of the manipulated amount are outputted to control valves 7.

Abstract: A stand-off control apparatus for plasma processing machines which is capable of maintaining an optimum stand-off even when a processing speed varies. In a stand-off control apparatus for plasma processing machines which is provided with a microcomputer (4) for maintaining an optimum stand-off (h.sub.0) by moving a torch toward/away from a work so that an independently inputted arc voltage (V) agrees with a speed-corrected target arc voltage (V.sub.O(F)) obtained by correcting a target arc voltage (V.sub.O), which is stored in advance, for an independently inputted processing speed (F), the microcomputer (4) determines at the time of varying a processing speed (F) whether the speed is being accelerated, being decelerated or being kept unchanged, and provides that the speed-corrected target arc voltage (V.sub.O(F)) for the respective case is applied after the lapse of a corresponding delay time (.DELTA.t) which is independently stored.

Abstract: A press machine having side frames which are effectively reinforced so as to appreciably reduce the noise generated during operation of the machine and improve the working accuracy of the machine without installing any special device on the outside thereof, significantly increasing the weight of the entire press machine, or obstructing a space between the side frames of the press machine. The side frames of the press machine are C-shaped in side view and are reinforced by at least one reinforcing member fixedly secured to each of the side frames at at least one predetermined place. The reinforcing members function to suppress the deformation of the opening of the C-shaped side frames to reduce noise and improve accuracy. The reinforcing members convert the vibrational energy of the side frames into heat energy which is then absorbed into the side frames.

Abstract: A shock absorbing device provided with a damping plate damper having a viscosity damper includes: a case body comprising an upper flange, a body portion, and a lower flange; a collared resilient member provided with a body portion and a collar portion, an outer surface of the body portion and an undersurface of the collar portion being connected to the case body; a center shaft connected to the central portion of the collared resilient member; a damping plate fixed to the bottom end portion of the center shaft; and a damper case fixed to the bottom end of the case body and filled with a viscous substance. An operator cabin of a construction machine is resiliently supported to the vehicle body through the shock absorbing device.

Abstract: A control unit for controlling load on a bulldozer in the case of manual intervention, comprising: an actual tractive force detector for detecting the actual tractive force of a vehicle body; a target tractive force setting device for setting a target tractive force for an automatic blade control mode in dozing operation according to the actual tractive force detected by the actual tractive force detector; and a blade controller for controlling a blade to be lifted or lowered such that, if there is a difference between the target tractive force set by the target tractive force setting device when switching from the automatic blade control mode to a manual operation mode takes place in dozing operation and the actual tractive force detected by the actual tractive force detector when return from the manual operation mode to the automatic blade control mode takes place, the actual tractive force gradually comes closer to the target tractive force set when switching to the manual operation mode takes place.

Abstract: This invention relates to the controlling of the travel of a crawler vehicle and aims at resolving the issue of making a crawler vehicle travel on an ungraded land with the crawlers effectively gripping the road surface. According to the present invention, the loads imparted to crawlers (12FL, 12FR, 12RL, 12RR) are detected, and, on the basis of the results of this detection, the sum of the loads on a pair of crawlers (12FL, 12RR) at the front left and rear right sides of the vehicle and the sum of the loads on another pair of crawlers (12FR, 12RL) at the front right and rear left sides thereof are computed. When a difference between the sums thus computed has become higher than a predetermined level, it means that a diagonal stuck has occurred.

Abstract: A method of using a camshaft miller for working a workpiece in which a plurality of journals are provided on the workpiece, cams having the same phases are disposed on both sides of each of the respective journals and a ring is disposed at one end of the workpiece, includes providing a cutter having, at a central portion thereof, a central chip for working a ring and other chips disposed on both sides of the central chip for simultaneously working cams having the same phases, working the cams of the same phases of each of the journals simultaneously with the other chips, subsequently with respect to the journals, and working the ring with the central chip. According to this method, the cams and the ring can be worked by a single working machine and the cams of each set thereof having the same phase can be simultaneously worked, thereby improving the productivity.

Abstract: An automatic cushioning control apparatus for a cylinder of a working machine provides a quiet cylinder cushioning effect, causing little shaking of a vehicle body, without using a mechanical cylinder cushion.

Abstract: A three-dimensional image display device which comprises a holographic plate having a plurality of holograms divided in correspondence with rotational angles, the holographic plate being exposed so that when light is irradiated, each of the holograms forms a point image at a different position in a depth direction of the holographic plate; a drive unit for rotating the holographic plate; a light irradiating unit including a plurality of light sources arranged substantially in a straight line so that the light sources are kept at substantially equal distances from the holographic plate, for irradiating the holographic plate with light from the light sources; and a controller for controlling the drive unit and lighting operations of the plurality of light sources of the light irradiating unit in accordance with a signal indicative of a three-dimensional image to be displayed so as to control lighting of a plurality of point images formed in a three-dimensional space, whereby a three-dimensional image can be obt

Abstract: A first stop valve (4) is connected in parallel with a serially connected second stop valve (7) and a gas flow regulating means (6) between a supply of working gas and a plasma torch (1). In response to a start signal S.sub.T, the second stop valve (7) is opened so as to supply the working gas at a small flow rate Q.sub.P to the plasma torch (1) via the gas flow regulating means (6). After a pilot arc is started, the first stop valve (4) is gradually opened so as to gradually increase the flow rate of the working gas from the small flow rate Q.sub.P up to a normal flow rate Q.sub.M, and at the same time, the pilot current is gradually increased from an initial pilot current level I.sub.S to a pilot current level I.sub.P, corresponding to the gradual increase in the flow rate of the working gas up to the normal flow rate Q.sub.M. In response to a stop signal S.sub.P, the arc current is gradually reduced from the cutting current level I.sub.M to a lower level I.sub.D at which the main arc (13) is extinguished.

Abstract: A steering system for a bulldozer, comprising a steering direction indicating device for indicating a lateral direction in which a vehicle body is to be steered, a dozing operation detector for judging by detection whether the bulldozer is in dozing operation, a steering controller for controlling the vehicle body to be steered in the lateral direction indicated by the steering direction indicating device when the dozing operation detector judges that the bulldozer is in dozing operation, by tilting a blade in the indicated lateral direction in order to impose offset load on the vehicle body, and by causing a difference between the relative travel speeds of right and left crawler belts attached to the vehicle body at least when light load occurs in the dozing operation.

Abstract: An asynchronous data transmission system for asynchronously transmitting data from a first system controller to a second system controller in which a memory for holding therein data to be transmitted has a duplex structure including first and second memories, output data of the first system controller is alternately written into the first and second memories in response to the data transmission of the first system controller, the reading operation of the second system controller is carried out over one of the memories over which the writing operation of the first system controller has been completed, the next writing operation of the first system controller is carried out over the other one of the memories.