Abstract: A method and apparatus is provided of detecting tool abnormality in a machine tool. Permissible minimum and maximum values of load current in a real cutting section are determined for a spindle motor and a servomotor during normal operation of the machine tool. The load current of the spindle motor and the servomotor is measured while the machine tool is operated. The load current measured in a real cutting section other than a non-cutting section is extracted by way of filtering the load current measured. A judgment is made as to whether the extracted load current is within a range between the minimum and maximum values. Occurrence of the tool abnormality is confirmed if the extracted load current falls outside the range. This enables the machine tool to detect not only overload condition due to excessive wear of a tool but also non-load condition induced by a tool breakage.

Abstract: A wear-resist mechanical component used in a frictional contact area requiring wear-resistance and a method of producing the same is provided. The method comprises the steps of: depositing hard particles of one or more substances selected from the group consisting of carbides, nitrides and borides on an iron-based metal body to a predetermined thickness; depositing binder powders atop of the hard particle layer to a predetermined thickness; and heating the hard particles, the binder powders and the iron-based metal body, so that the iron-base metal body and the hard particles are bonded together. This can obtain a wear-resistant mechanical component having high hardness and excellent wear resistance without having to go through the step of mixing hard particles with binder to form the mixture. The super-hard alloy can be bonded to the base metal body regardless of the shape of the base metal body.

Abstract: A tool magazine feeder for an automatic tool changer for feeding a tool magazine to a spindle comprises a carriage horizontally movable, under the state of supporting the tool magazine, between a remote position where the carriage is separated from the spindle and a proximate position where the carriage is adjacent to the spindle, a driving mechanism for reciprocating the carriage from the remote position to the proximate position and vice versa, and a guide mechanism positioned between the carriage and the driving mechanism. The guide mechanism is provided with one or more rollers and one or more rails for guiding the carriage to horizontally move between the remote position and the proximate position.

Abstract: A cooling device for cooling a built-in-spindle type spindle motor of a machine tool, in which the spindle motor includes a motor housing enclosing a spindle, a rotor fixed around the spindle, and a stator secured to the inner circumferential surface of the motor housing to surround the rotor with a clearance being formed between the rotor and the stator, wherein the cooling device comprises: a cooling gas supply source for supplying cooling gas; a motor housing with a cooling gas introduction passage for introducing and guiding the cooling gas supplied from the cooling gas supply source to one side of the rotor and the stator; and a cooling gas injection nozzle removably installed in the motor housing and having one or more nozzle openings oriented to inject the cooling gas to the clearance between the rotor and the stator.

Abstract: A method is provided of producing a hardmetal-bonded metal component with an enhanced bond strength. The method comprises the steps of providing an iron-based metal body, mixing and compressing raw material powder of hardmetal and binder powder containing nickel, silicon and boron into a preform, heating and sintering the preform, and applying heat to the sintered body and the iron-based metal body under a state that the sintered body is brought into contact with the iron-based metal body, to thereby cause the sintered body to be bonded to the iron-based metal body. The sintered body and the iron-based metal body are thermally treated at a temperature of 1,000 to 1,200° C. for 30 or more minutes so that boron present in the sintered body is infiltrated into grain boundaries of the iron-based metal body to form a plurality of boride spikes in a bonding interface.

Abstract: A fuel tank cradle device for forklift trucks is swingable to the lateral side and then foldable into a substantially vertical position, thereby assuring easy and safe change of a used fuel tank with a new one. The cradle device includes a counterweight, a cradle provided with a first body and a second body, the first body pivotally mounted to the counterweight for rotation between a home position above the counterweight and a rotated position outside of the counterweight, the second body capable of replaceably supporting a fuel tank and foldably connected to the first body so that the second body can be moved between an unfolded position and a downwardly folded position with respect to first body, and a locking arrangement for locking the cradle to the counterweight while the first body of the cradle is at the home position.

Abstract: An automatic tool changer for machine tool comprises a machine frame with a changer frame portion, and a spindle rotatably attached to the machine frame and adapted to removably grip a tool in position. An up-down carriage is mounted to the changer frame portion of the machine frame for elevational movement between a raised position and a lowered position. A magazine carriage is laterally movably mounted to the up-down carriage for movement between a home position far away from the spindle and an operative position close to the spindle. A tool storage magazine is carried by the magazine carriage and has a plurality of tool holders for changeably holding different kinds of tools. A vertical magazine actuator serves to cause the up-down carriage, the magazine carriage and the tool storage magazine to move in a vertical direction. A horizontal magazine actuator is adapted to cause the magazine carriage and the tool storage magazine to move in a horizontal direction.

Abstract: A method is provided of producing a hardmetal-bonded metal component with an enhanced bond strength. The method comprises the steps of providing an iron-based metal body, mixing and compressing raw material powder of hardmetal and binder powder containing nickel, silicon and boron into a preform, heating and sintering the preform, and applying heat to the sintered body and the iron-based metal body under a state that the sintered body is brought into contact with the iron-based metal body, to thereby cause the sintered body to be bonded to the iron-based metal body. The sintered body and the iron-based metal body are thermally treated at a temperature of 1,000 to 1,200° C. for 30 or more minutes so that boron present in the sintered body is infiltrated into grain boundaries of the iron-based metal body to form a plurality of boride spikes in a bonding interface.

Abstract: A system for real time three-dimensional model display in a machine tool includes a plurality of motors each capable of providing relative movement between a tool and a workpiece along an associated one of multiple axes, a servo driver for controlling the motors, a numerical controller coupled to the servo driver for transmitting target three-dimensional coordinates of points stored in a memory to the servo driver such that the motors can be caused to move into the target coordinates of points and for receiving actual three-dimensional coordinates of points fed back from the motors, and an image processor for receiving the actual three-dimensional coordinates of points from the numerical controller and for directly transmitting the actual three-dimensional coordinates of points to a display screen, so as to achieve a real time workpiece shape display based on the actual three-dimensional coordinates of points of the motors.

Abstract: A fuel tank cradle device for forklift trucks is swingable to the lateral side and then foldable into a substantially vertical position, thereby assuring easy and safe change of a used fuel tank with a new one. The cradle device includes a counterweight, a cradle provided with a first body and a second body, the first body pivotally mounted to the counterweight for rotation between a home position above the counterweight and a rotated position outside of the counterweight, the second body capable of replaceably supporting a fuel tank and foldably connected to the first body so that the second body can be moved between an unfolded position and a downwardly folded position with respect to first body, and a locking arrangement for locking the cradle to the counterweight while the first body of the cradle is at the home position.

Abstract: A semi-automatic power shift transmission for use in a forklift truck includes a manual shift lever with first and second gear positions, a hydraulically shifted transmission gear mechanism operable in one of first and second gear ratios corresponding to the first and second gear positions, a plurality of solenoids for, when energized, causing the transmission gear mechanism to be either up-shifted from the first to the second gear ratio or down-shifted from the second to the first gear ratio, a transmission speed sensor for detecting the output speed of the transmission gear mechanism to generate a transmission speed signal, an engine speed sensor for picking up the speed of a vehicle engine to produce an engine speed signal, a steering wheel angle sensor for measuring the steering wheel angle to issue a wheel angle signal, and a transmission control unit responsive to the transmission speed signal, the engine speed signal and the wheel angle signal for selectively energizing the solenoids to thereby carry o

Abstract: A spool-out type booster brake valve device for industrial vehicles is configured to allow hydraulic working fluid to be supplied not only to a booster chamber but also to a master chamber thereby eliminating the need to use a separate brake fluid reservoir tank for supplementing brake fluid in the master chamber. The brake valve device is used in an industrial vehicle equipped with a fluid pump, a reservoir tank and a brake actuator. The brake valve device includes a valve body having an inlet port, a drain port, a brake port, a booster chamber communicatable with the pump via the inlet port and a master chamber communicatable with the brake actuator via the brake port. The master chamber is connected to the inlet port to receive working fluid from the pump. A valve spool is slidably fitted in the valve body through the booster chamber and the master chamber, the valve spool being shifted between an idle position and an operating position.

Abstract: A loader with a controlled vertical path of a working implement comprises a frame and a pair of laterally spaced lift booms disposed at opposite lateral sides of the frame for elevational movement between lowered and raised positions, each of the lift booms having a forward free end which carries a working implement and a rear proximal end articulately mounted to the frame. A pair of front control links are arranged on the opposite sides of the frame, each of the front control links having a first end pivotally attached to the frame at a first pivot point and a second end pivotally connected to the rear proximal end of the respective lift boom at a first connection point.

Abstract: A fire grate assembly for stoker incinerators. A plurality of stationary and movable grate members are alternately arranged in the assembly. The assembly also has a preventing member, such as a liner plate, which is detachably mounted to an end of each of the movable grate members for preventing the stationary grate members and the movable grate members from directly contacting each other, while allowing the movable grate members to be linearly movable relative to the stationary grate members. The preventing member is replaceable and can have a countersunk hole, thus being adapted for bolting the end of each of the movable grate members.

Abstract: A loader which can provide the operator with enhanced safety comprises a vehicle body carrying a canopy and a rotating vehicle axle, a seat bar mounted to the canopy for swinging movement between a raised position and a lowered, operator restraint position, a parking lever shiftable between a brake position and a release position and cooperatingly associated with the seat bar, an axle lock operatively connected to the seat bar and the parking lever and operable to lock or release the vehicle axle, and conditional force delivery mechanism for normally allowing the axle lock to brake the vehicle axle and for causing the axle lock to release the vehicle axle only when the seat bar is in the lowered position with the parking lever shifted into the release position.

Abstract: A bulk material pump device includes first and second hydraulic drive cylinders capable of causing alternate reciprocating movement of the corresponding pumping pistons to pump concrete contained in a hopper through a transportation conduit. The first drive cylinder has a cylinder housing whose bore is divided into a base chamber and a head chamber by a drive piston slidably received in the cylinder housing. The base chamber is in fluid communication with an oil pump while the head chamber is connected to the second drive cylinder. Under a loaded operation condition, a part of the pressurized oil in the base chamber is admitted into the head chamber via a head bypass line at the end of retracting movement of the drive piston and almost the same amount of the oil is returned back from the head chamber to the base chamber via a base bypass line at the end of extending movement thereof.

Abstract: A power-shifted transmission for industrial vehicles comprises a transmission casing and input and output shafts rotatably mounted on the transmission casing. The input and output shafts are drivingly connectable to each other through a forward shaft assembly, a reverse shaft assembly and an intermediate shaft assembly. The forward shaft assembly is rotatingly driven by the input shaft and operable to deliver the torque of the input shaft to the output shaft at a first or second forward gear ratio. The reverse shaft assembly is rotatingly driven by the forward shaft assembly and operable to deliver the torque of the input shaft to the output shaft at a first or second reverse gear ratio. The intermediate shaft assembly is rotatingly driven by the reverse shaft assembly and operable to deliver the torque of the input shaft to the output shaft at a third forward gear ratio.

Abstract: A pump motor mounting arrangement includes a vehicle frame and a motor bracket fixedly secured to a side of the pump motor, the motor bracket having an upper extension and a lower extension to which a bottom positioning bolt is removably attached. A support ledge is affixed to the vehicle frame for supporting the lower extension of the motor bracket. The support ledge has a slot extending generally in parallel to the vehicle frame and receiving the head of the bottom positioning bolt. The pump motor mounting arrangement further includes a top fixture plate for, when tightened, depressing the upper extension of the motor bracket against the vehicle frame to keep the pump in place and for, when loosened, allowing the pump motor to be slidingly moved on the support ledge into a temporary maintenance position.

Abstract: A self-diagnostic method is provided capable of testing condition of various components for a forklift truck selectively, displaying the result test codes collectively on a display after completing the test, and initiating a quick test mode during a run mode by simply manipulating an accelerator pedal and a direction lever of the forklift truck.

Abstract: A loader includes a vehicle body with a canopy and a seat, a hydraulically operated working implement and a hydraulic control valve unit for controlling flow of working fluid to and from the working implement. Mounted to the canopy of the vehicle body is a seat bar for swinging movement between a lowered position in which an operator is secured to the seat and a raised position in which the operator is released from the seat. A pedal with a dog plate is operatively associated with the control valve unit and tiltable about a horizontal axis between an operative position wherein the control valve unit allows the fluid to be fed to the working implement and a neutral position wherein the control valve unit inhibits delivery of the fluid to the working implement.