Abstract: A wire electric discharge machine having a simple mechanism for retracting and collecting a cutoff piece (machined chip or machined product). A cutoff piece receiving basket for receiving a cutoff piece produced during machining is attached to a support bar mounted to a lower guide block, the basket being rotatably supported by a rotary support shaft. A bearing provided in the support bar is located immediately short of a cam block, and then fitted into a slot by X-axis movement. A moment is applied to the support bar by Y-axis movement to rotate the cutoff piece receiving basket around the rotary support shaft, so that the basket is retreated to above a cutoff piece collecting box and then turned over, whereby a cutoff piece received in the basket falls into the collecting box. The cutoff piece receiving basket may be rotated manually or rotated by use of a robot, a special-purpose motor, an air cylinder, etc.

Abstract: A spindle protective structure in a spindle-through coolant feeder capable of preventing coolant form invading a spindle and a spindle motor for an excessive overflow of coolant. Coolant is supplied into a through hole formed axially in the spindle or a shaft connected to the spindle through a stationary member and a rotary member of a rotary joint supported by a housing. A seal member having elasticity is provided on a circumferential surface of the spindle or the shaft. Coolant which leaks through the seal member is splashed by a fringer provided in the housing. When a large amount of coolant is overflowed in the housing, a pressure of the coolant in a first chamber of the housing increases to press a lip of the seal member towards the circumferential surface of the spindle or the shaft to prevent leakage of coolant into a second chamber of the housing.

Abstract: A robot movement programming method and apparatus for effectively creating a program for operating a robot with respect to workpieces of identical or similar shape. Sample programs for specifying sequence patterns suitable for the robot operations to be carried out are prepared, and also conversion formulas for obtaining teaching point position data are prepared as functions of dimensional parameters. The sample programs and the conversion formulas associated therewith are registered in a pattern library. The operator selects from the pattern library a sample program representing the sequence pattern suited for the robot operation to be carried out and designates the sample program as a base for creating a robot movement program after editing it, if necessary. Then, the operator inputs various parameter values, watching a graphic image of the sequence pattern specified by the selected sample program.

Abstract: An acceleration/deceleration method capable of synchronizing two axes in velocity and also in position. The follower axis X is continued to be accelerated after the velocity Vx of the follower axis X reaches the target velocity Vy of the follower axis Y and the acceleration is changed over to a deceleration to direct the target velocity Vy. The time for changing over the acceleration to the deceleration is determined so that the motion amount of the position Px of the follower axis X in excess of the motion amount of the position Py of the objective axis Y is equal to the sum of the displaced motion amount in the acceleration motion and an initial positional difference. Thus, the position and velocity of the follower axis X coincide with the position and velocity of the objective axis Y to achieve complete synchronism of the two axes in the case where there is a positional difference and a velocity difference between the two axes.

Abstract: A machining limit area specifying method and a manual feed machining method using a numerical control unit capable of easily performing machining in a desired shape by manual feed. In specifying a machining limit area on an X-Y plane, a desired machining shape is defined by shaping data or a combination of some shaping data on the X-Y plane at a predetermined Z-coordinate, and the desired machining shape defined by the shaping data is specified as a machining limit area in which movement of a tool is permitted on the X-Y plane in manual machining using the numerical control unit. In specifying a machining limit area in the Z-axis direction, an inverse function using an X- or Y-coordinate value as a parameter is obtained based on a function for specifying the machining limit area on the X-Y plane on condition that a Z-coordinate value is used as a parameter, and the machining limit area in the Z-axis direction is specified based on the inverse function.

Abstract: A controller is obtained by adding the function of a virtual operator to a numerical control device. Data on the construction and capacity of a machine, as a control object, are stored as system data in advance. Work instructions are inputted by the operator or through a host system. The virtual operator, comparing the contents of the work instructions with the system data, determines whether automatic processing is possible or manual processing is required. If the automatic processing is possible, the automatic processing is carried out. If the manual processing is necessary, explanation diagrams, messages, etc. are displayed. Every time a request button for further explanation is depressed, a more detailed work explanation is displayed. Thus, the operation is simplified, and the work explanation can be obtained according to the skill of the operator.

Abstract: Interactive data processing unit which is located at a distance from an FA control unit and capable of direct access to a memory in the FA control unit. When an access request to a memory (3) in a CNC (30) is issued by a device in an MMC (20), a remote access control means (1) outputs the access request to the CNC (30). Upon reception of the access request, an internal data input/output means (2) in the CNC (30) makes access to the requested address by performing a direct memory access (DMA) operation to the memory (3). It writes the data into the memory when the access request is a write-request. On the other hand, when the access request is a read-request, the internal data input/output means (2) outputs the data to the MMC (20). The remote access control means (1) in the MMC (20) receives the data and forwards it to the device which issued the access request. The MMC (20) thereby makes access directly to the memory (3) in the CNC (30).

Abstract: A method of preventing interference of an industrial robot in which teaching of an operation program to the robot is easy and interference of the robot with an external cooperative apparatus can be easily avoided. If a current position of a reference point on the robot for detecting interference is outside a common area (S12) and a target position of the reference point is outside the common area (S18), a motion command is outputted to drive the robot. If the target position of the reference point is within the common area, it is determined that whether or not a movable part of the cooperative apparatus is within the common area, and if the movable part is outside the common area, an operation forbidding signal for the cooperative apparatus is turned on and the motion command is outputted to make the robot move. If the movable part of the cooperative apparatus is within the common area, the motion command is withheld till the movable part of the cooperative device moves out of the common area (S4, S5).

Abstract: A torque command Tc is restricted to a torque limit value Tm′ by torque limiting means and delivered to current restricting means for a motor. The torque limit value Tm′ is derived by adding a torque limit correction value &Dgr;Tm as calculated by torque limit correction value calculating means to a torque limit value Tm corresponding to the target pressing force F. The torque limit correction value &Dgr;Tm is supplied in accordance with the acceleration value when the motor is accelerated or decelerated. This acceleration is calculated from the feedback velocity Vf from the velocity detector, or the command velocity Vc. Alternatively, it may be derived from the output of an observer which inputs the torque command Tc′ supplied to the current control means of the motor, and the feedback velocity Vf.

Abstract: A laser machining apparatus capable of removing spatters and slugs produced in piercing and rising supply pressure of blow gas sufficiently without hindering a jet of assist gas. A piercing assist jig can be turned and moved up and down by a rotary air cylinder and an extendable air cylinder which are attached to a machining head. When piercing is to be performed, the piercing assist jig, which is in a position where it does not interfere with the machining nozzle and the workpiece, is turned to make a center of a hole of the piercing assist jig coincide with a center of the machining nozzle. Then the machining head is moved down to a piercing position, and the piercing assist jig is pressed on a workpiece. Then, a laser beam is irradiated and assist gas is jetted, and also blow gas is jetted from a blow gas supply opening so that the blow gas flows with the assist gas therebetween. Spatters and slugs flying up in the process of piercing are removed by the blow gas without hindering the piercing.

Abstract: A motor controller for controlling currents flowing to a motor by the PWM system includes interruption-restart controller for interrupting supply of PWM commands for at least one phase when the actual current flowing in at least one motor phase has exceeded a specified value, and for thereafter restarting PWM command supply. When the actual current flowing to the motor has reached a previously determined anomalous level, control is performed to interrupt and restart supply of PWM commands. By interrupting the supply of the PWM commands, the current flowing to the motor is returned from an anomalous level to a normal level and the equipment protected. After the motor current is returned to a normal level by the interruption of PWM command supply, PWM command supply is resumed, normal control by PWM command is again performed, and a non-controlling state in the controller is avoided.

Abstract: Axes used for posture alignment are selected from the axes of a work coordinate system W and a tool coordinate system T, and an angle of intersection between those selected axes are set. A robot is then driven so that the selected axes intersect with each other by the set angle of intersection in response to a posture alignment instruction, causing the tool to assume a target posture with respect to a workpiece. Further, angles for rotating the work coordinate system about each axis thereof are set, then the robot is automatically moved so that a coordinate system produced by rotating the work coordinate system by the set angle in response to a posture alignment instruction. Further, the tool coordinate system set at a movable part of a tool is automatically reset according to an amount of movement every time the movable part of the tool move, and the robot is manually fed based on the tool coordinate system thus reset.

Abstract: An image of a workpiece is taken by a CCD camera, which includes a view field covering a supply range of the workpiece, and is transmitted to an image processor to detect the position and posture of the workpiece. A robot controller controls a robot to approach a position from another position based on the result of the detection. Then, a measurement using a laser sensor is started. Scanning laser beams projected from an emitter are detected by a light detector and the detected data are analyzed by the image processor. When the robot reaches a third position, the measurement is terminated. The laser sensor may be of a split-light-projection type. For the approaching movement, the image taken by the camera is displayed on a display device to perform a jogfeed of the robot on the screen.

Abstract: A control mode changing over method for a servo control system, which is capable of reducing a shock occurring in changing over a control mode from a torque control mode to a position/velocity control mode. In the torque control mode, a value of an integrator in a velocity loop for the position/velocity control mode is rewritten into a torque command value for torque control so that the value of the integrator is always set to the same value as the torque command. When a control mode is changed over from the torque control mode to the position/velocity control mode, a torque command value for a servo motor is obtained based on the value of the integrator rewritten in the torque control mode. Thus, a continuous torque command value is given to the servo motor in changing over the control mode.

Abstract: The present invention corrects a teaching point set in a robot movement control program to another position using jog-feed buttons. A robot tool is moved by jog-feed buttons using a jog-feed command unit toward a position to which a teaching point is to be corrected. When the position of the tool approaches any teaching point contained in a movement command program, the robot is automatically shifted to the teaching point to be corrected in the movement command program. When the teaching point to be corrected is found, correction of a teaching point from the closest teaching point to the position to be corrected is then performed.

Abstract: A superimposing control method using a numerical control device, capable of starting and terminating a superimposing control even during movement, without the need of waiting for the adjustment of timing and without rapid acceleration or deceleration. In response to a superimposition command, a motion value distributed to a Z axis of a superimposing axis in a reference system is subjected to acceleration/deceleration processing by an acceleration/deceleration processing section separately provided for superimposition, and the obtained movement value is added to a motion command value for a Z axis of a superimposed axis in a superimposing system. When a superimposition termination command is issued, the motion command value remained in the acceleration/deceleration processing section for superimposition is superimposed on the motion command value for the Z axis of the superimposing system. The superimposition can be smoothly started and terminated without the need to stop the two control systems.

Abstract: In a gas laser blower, the lower end opening of the oil passage (14) extends below the liquid level of the oil reservoir (17), so that the internal chamber (18) of housing and the oil passage (14) are separated by the oil within the oil reservoir. Further, a cylindrical guard (24) is disposed around the lower bearing (6) which supports the shaft so that the oil and oil mist scattered from the bearing are caught by the guard (24) and is returned to the oil reservoir.

Abstract: The present invention relates to a method of automatically assigning a single welding apparatus corresponding to a single robot, which is selected as a control object, in a welding robot system capable of controlling a plurality of robots and a plurality of welding apparatuses with a single control unit. The relations of correspondence between the robots and the welding apparatuses are first predetermined, and the predetermined relations of correspondence are stored in a memory of the control unit. When a single robot is designated through a teaching console panel for executing a given welding operation, the specific welding apparatus corresponding to the designated robot is automatically determined according to the relation of correspondence stored in the storage unit. As a result, the designated robot and the corresponding welding apparatus are started.

Abstract: A welding voltage value Vf and a welding current value IF are respectively monitored by a detector during execution of arc welding in accordance with a robot operation program, indexes are calculated which show how far the monitored values Vf and If are deviated from a command welding voltage value Vc and a command welding current value Ic specified in the operation program, and it is decided that there is a possibility of occurrence of a defective weld in arc welding under execution, when the calculated index exceeds a preset threshold value. Then, the data for arc-welding execution conditions and execution results are cumulatively stored in a defective weld history data area provided in a memory in accordance with the line number and the statement of the line in the operation program for each line constituting the program, and the cumulatively-stored data is displayed on a screen.