Abstract: An induction motor has a stator formed by inserting and holding piled steel plates (12) between end plates (11a, 11b) and welding support bars (13) consisting of nonmagnetic metal along the external surface of said piled steel plates.

Abstract: The present invention increases screw cutting accuracy and simplifies the control of a screw cutting control system which performs screw cutting through the use of a numerically-controlled machine tool. A tapper (TPP) connected to a spindle, holds a tap (TAP) in a manner to be movable in the axial direction of the spindle, transmits the rotation of the spindle to the tap (TAP) for a predetermined range of forward axial movement of the tap (TAP) and transmits the rotation of the spindle to the tap (TAP) when the spindle is reversed. During screw cutting, feed by a feed motor (SZ) stops after the tap (TAP) enters a workpiece and the screw cutting is effected by the thrust of the tap itself resulting from the rotation of the spindle. The sequence of screw cutting is commanded by one block of command data.

Abstract: A robot wrist of an industrial robot having a wrist housing supporting two orthogonally arranged rotating output shafts therein, each of the shafts being connected to a robot hand, and a built-in fluid conveying means provided for distributing pressurized air introduced from the outside of the robot wrist toward the robot hand attached to one of the rotating cutput shafts. An output end of each of the two rotating output shafts may either be plugged by a plug element or closed by a stop valve when the output end is not connected to the robot hand.

Abstract: A device for operating a hand of an industrial robot is so constructed that fluid pressure cylinders (43, 44) are provided as a driving mechanism of the hand (4) of the industrial robot, branch passages including a pressure-reducing valve (47) are provided in a fluid supply passage to the fluid pressure cylinders (43, 44), the supply of fluid is switched by solenoid valves (SV.sub.2, SV.sub.3, SV.sub.4), and the switching of the solenoid valves (SV.sub.2, SV.sub.3, SV.sub.4) is carried out in accordance with the selected grasping force which has been selected in the teaching mode of the industrial robot, whereby the grasping force of the hand can be controlled stepwisely.

Abstract: An industrial robot control method and apparatus having a pulse distributing circuit for executing a pulse distribution operation on the basis of positional command data from taught data to generate distributed pulses, a pulse coder for generating a feedback pulse each time the industrial robot moves a predetermined amount along the Z-axis, an error register for storing the difference between the number of distributed pulses and the number of feedback pulses, and positional control circuitry for positionally controlling the industrial robot in such a manner that said difference approaches zero, compensation being effected for an amount of bending .DELTA.Z of an arm when a workpiece of weight W is gripped. The industrial robot control apparatus includes a memory for storing an amount of bending .DELTA.Z.sub.o of the arm when a workpiece having a predetermined weight W.sub.o is gripped at an arm length l.sub.o, an arithmetic circuit for computing an amount of bending .DELTA.

Abstract: A numerical control system which includes an automatic programmer and at least one numerical control device interconnected by a cable, in which a numerical control program prepared by the automatic programmer is transferred to the numerical control device. The automatic programmer includes an input unit for entering data, a processor which edits the data for producing a numerical control program, a memory for storing the complicated numerical control program, and a display device which displays a graphic in accordance with the output of the processor. The numerical control device includes a memory for storing the numerical control program, which is transferred from the automatic programmer via the cable.

Abstract: A system for detecting the rotational speed of a rotating body comprising the steps of generating two kinds of signals A and B having alternating wave forms and corresponding to the rotational speed of the rotating body by means of position-detecting devices (5a, 5b), the signals A and B having the same amplitude and having phases deviating by 90.degree.

Abstract: A method and system for rewriting data in a non-volatile memory in which the rewriting of one access unit of stored data is executed by erase and write cycles, the stored data being protected in the event of an interruption in electric power. In rewriting into second data the first data which is stored in a data storage area of the non-volatile memory, either the first or the second data is stored in a save area of the non-volatile memory, after which the first data in the data storage area is erased, followed by the writing of the second data in the data storage region to complete the rewrite operation.

Abstract: The coordinate values (X, Y, Z) for the position of the front end of a tool and the vector (I, J, K) of the axial direction of the tool are read in from a command tape by a tape reader. Using these values and a tool length l set by a dial or the like, a movement data calculation circuit calculates the orthogonal coordinate values (x, y, z) of the position Q of the center of rotation of the tool and spherical coordinate values (b, c) indicative of the position of the rotational angle of the tool. After these coordinate values are converted into pulses for moving the tool in the respective axial directions by a pulse distribution circuit, servomotors are driven by the pulse signals and through servo circuits so as to move the tool or a table to a desired machining position.

Abstract: A method and apparatus for controlling the return of a movable element of a machine tool to a predetermined grid point by controlling a movable element drive device in accordance with feedback pulses generated while the drive device is being driven to transport the movable element between grid points. The method includes the steps of specifying a position remote from the predetermined grid point by a distance which is less than the spacing between grid points, computing the deviation between the specified position and the current position of the movable element, positioning the movable element at the specified position by driving the drive device on the basis of the computed deviation and the feedback pulses, and driving the drive device at reduced speed to stop the movable element at the first grid point encountered following the initiation of reduced-speed drive.

Abstract: The present invention relates to a novel numerical control device which enables failures to be diagnosed even when a failure develops in a main processor for executing numerical control as well as failure diagnosis in hardware and the like. The invention includes a bus switching circuit provided in a main bus of an NC device. The NC device also includes a main processor for carrying out numerical control, a main memory, a tape reader, a numerical control panel and position control circuits. Further provided are a service processor for carrying out failure diagnosis and a service memory. When a failure develops in the main processor, the service processor immediately halts the execution of instructions by the main processor, the service processor is then connected to the main bus by the switching action of the bus switching circuit, and the service processor executes failure diagnosis by means of a diagnostic program for diagnosing failures, which program has been previously written into the service memory.

Abstract: In an apparatus for processing a broken wire electrode in a wire-cut electric discharge machine for cutting a workpiece into a desired contour by electric discharge machining while the workpiece is transported relative to a wire electrode on the basis of machining command data, there is disclosed an apparatus for processing a broken wire electrode including a memory (CPX, CPY) for storing the position at which the wire electrode broke, an operator's panel with jog buttons (PJX, MJX, PJY, MJY) for generating a movement command following wire breakage to retract the workpiece from the wire breakage position (Xc, Yc), motors and drive circuitry (PD, SX, SY, MX, MY) for transporting the workpiece to a predetermined position on the basis of command, and a fitted point return button (Br) on the operator's panel for generating a signal to position the workpiece at the wire breakage position after the wire electrode is rethreaded in a wire transfer system.

Abstract: An industrial robot having a trunk mounted for vertical and rotational movement on a stationary base is provided with two arm members extensible from the said trunk having a robot wrist mechanism attached to their ends. The extending and contracting movements of the arm members, rotational movement of the wrist and swinging movement of the wrist are controlled, respectively, by three electric servo motors mounted in a mounting compartment positioned on the side of the trunk opposite to the extensible arms.

Abstract: A numerical controller having an extended optional block skip function which permits selection of an optional block in a certain specific section of an execution program. In a numerical information storage medium is stored a cutting program in which a specific block is provided with skip object indicating information and skip select information, which is data for deciding whether to skip over the block and which can assume at least two values. Information indicating which ones of the blocks specified as the objects of optional block skip control are to be validated and invalidated is entered from a block select switch. A block skip circuit checks whether or not the skip object indicating information is present at the head or intermediate portion of each block. If not, the block is selected and, if the information is present, the skip select information is collated with information from the block select switch.

Abstract: Position error correction equipment with which it is possible to perform a backlash correction or a pitch error correction with a high degree of accuracy even if the state of a numerical control machine tool, for instance, temperature, varies. Error correction data groups predetermined by measurement in respective states of the numerical control machine tool are stored in an error storage circuit (MEM) corresponding to the respective states. An error correction data selecting circuit (MPX) selects an error correction data group corresponding to a particular state of the numerical machine tool from the error correction data groups stored in the error storage circuit (MEM). A position correcting circuit (CPG) carries out a position correction by adding a correction pulse to a command pulse or feedback pulse from a position detector through utilization of the error correction data group selected by the error correction data selecting circuit (MPX).

Abstract: A system for controlling an industrial robot having a wrist (1) driven to rotate by a direct-current motor (2) having a servomechanism, wherein stroke-limit position control (6) of the wrist and rotational control (7) of the wrist can be selectively carried out.

Abstract: Disclosed is a numerical control method for a numerical control (NC) system having a device to execute a mirror image function wherein the moving direction of a movable member is reversed with respect to a commanded direction for each control axis, and a memory device to store coordinate values of a commanded position and coordinate values of a current machine position. This numerical control method comprises a step of storing the respective axial coordinate values of the current machine position at the time that the mirror image function has become effective, a step of calculating the commanded position coordinate values (CP) of directly preceding NC data after the mirror image function has become effective, by using the current machine position coordinate values and the position coordinate values at the time that the mirror image function has become effective, a step of calculating an incremental value (CP.sub.n -CP) of the control axis, CP.sub.

Abstract: In a non-contacting, speed-detecting device of a DC generator type; comprising a cylindrical permanent magnet rotator 1 having N and S poles distributing alternatingly in the circumferential direction, a stator 2 facing said rotator 1 in which stator output windings 4 are wound, a permanent magnet 3 for location rotating coaxially with the rotator 1, and magnetic induction switches 5 positioned close to the circumference of the magnet 3; switching the flat portions of the multi-phase trapezoid AC signals generated in the output windings by switches 5 in response to the rotating position of the magnet 3 for location; and obtaining a DC voltage proportional to the speed; the S pole regions and the N pole regions of the magnet 3 for location are formed continuously so that the magnetic field is inverted steeply from one polarity to another polarity, and the ratio of the width of the S pole regions and the width of the N pole regions is selected to be a value other than one, whereby only the flat portions of the

Abstract: A control device for indexing a stepping rotatable member, such as a turret of an NC lathe, comprising a means for generating code signals which generates different code signals at every stop position of the stepping rotatable member (TR), a means for generating strobe signals which generates the strobe signals used for reading said code signals at every stop position of the stepping rotatable member, a first comparator circuit which compares an indexing command value and the code signal, a counter which is preset by the code signal and which counts the strobe signal, and a second comparator circuit which compares a count value of the counter and the code signal value, the control device for indexing a stepping rotatable member outputs an end of indexing signal when both the comparator circuits detect coincidences.

Abstract: A workpiece feeder for successively feeding workpieces to a predetermined workpiece gripping station of the robot's hand. The workpiece feeder includes a conveyor having a plurality of interspaced pallets traveling on a table. Each pallet comprises a lower plate having a central opening and an upper plate which is detachably mounted on the lower plate. The workpiece feeder is provided with a lifting means having a vertically movable platform which ascends through the central opening in the lower plate to lift the upper plate away from the lower plate, thereby elevating the workpiece on the pallet up to the level of the gripping position of the robot's hand. The workpiece feeder further comprises a stop mechanism for limiting the topmost position of the platform. The workpiece feeder according to the invention is particularly suitable for use with an industrial robot of the simplified type in which the upright stand enabling the robot's hand to perform vertical translational movement is omitted.