Abstract: A spindle control system which is provided with a first motor for rotating a spindle, a second motor for positioning the spindle, a pulse generator for generating pulses proportional in number to the rotational angle of the spindle, a counter for counting the pulses from the pulse generator in order to detect the rotational position of the spindle, and circuitry response to the counter means to control positioning of the spindle by the second motor.

Abstract: When machining with a numerical-controlled machine tool, both a command value providing the configuration of a finished product and a compensation value depending on the tool are needed, and tool compensation data must be corrected in response to tool wear. The present invention, taking notice of the fact that correction data corresponding to tool wear can be predetermined from the frequency or time of tool use and the fact that the amount of tool wear can be unequivocally determined by the quality of materials of the tool and work, provides circuitry for counting the frequency or time of use of the tool and circuitry for correcting by a predetermined value the content of a compensation value register having tool compensation date when the number of times a tool has been used or when the duration of tool use has reached a predetermined value.

Abstract: A difference signal corresponding to the difference between the displacement of a stylus of a tracer head and a reference signal is integrated and the sum of the integrated value and the difference signal is applied as an error signal to a command velocity function generator and a correcting velocity function generator to produce a command velocity signal and a correcting velocity signal, respectively, which are provided to a distributing circuit. A displacement direction signal from an index circuit is supplied to the distributing circuit to derive therefrom respective axis command velocity signals for effecting profile control.

Abstract: The invention relates to a speed control system which includes an inverter circuit for converting a direct current into a polyphase alternating current in the form of a rectangular wave by the switching action of transistors, and an inverter drive circuit adapted to apply control signals to the inverter circuit to bring its output frequency to a desired value, an AC motor being rotated by the alternating current supplied by the inverter circuit. The system features current detection means for detecting the current that flows thrugh the input side of the inverter circuit, and a circuit adapted to terminate the operation of the inverter circuit when the value detected by the current means approaches a value large enough to damage the inverter circuit transistors as at such time that a large momentary current is subjected thereto.

Abstract: The time for positioning of a machine under numerical control is determined so that the positioning is finished at the moment when the amplitude of vibration of the machine is reduced to zero. In the thus predetermined time at least accelerating control and decelerating control are conducted to achieve control for positioning the machine at a commanded position.

Abstract: A system for a DC motor associated with a field winding and driven by using a three-phase anti-parallel thyristor bridge circuit, comprising a first means for controlling an armature current I.sub.a flowing through an armature of the DC motor, and; a second means for controlling a field current I.sub.f flowing the field winding by obtaining the feedback values of a voltage E.sub.a of the armature and the field current I.sub.f and by changing the maximum level of the current I.sub.f in accordance with a three-phase alternating voltage V.sub.ac applied to the three-phase anti-parallel thyristor bridge circuit. In the system, when the three-phase alternating voltage V.sub.ac decreases to a value lower than a predetermined value V.sub.o, the field current I.sub.f are decreased so that the armature voltage E.sub.a is decreased.

Abstract: A device for detecting opposite phases and an open phase in an input three-phase voltage for a DC motor, wherein the input three-phase voltage is rectified by a three-phase bridge circuit and supplied to the armature of the DC motor. The input three-phase voltage is supplied to the three-phase bridge circuit when the maximum level is equal to or less than the reference voltage, while the input three-phase voltage is not supplied to the bridge circuit when the maximum level is greater than the reference voltage. In this case, both opposite phases and an open phase can be detected by using a common device. In addition, only two phases, such as U- and W-phases, are used for detecting opposite phases and an open phase no matter how these phases may be generated in any phase such as U-, V- or W-phase of the input three-phase voltage. As a result, the device is small in size, simple in electrical construction and low in cost.

Abstract: A control system for driving a rotary shaft and for positioning the shaft at a commanded position with one motor and two rotation transmission mechanisms of different ratios provided between the motor and the rotary shaft. The two transmission mechanisms are adapted to be selectively actuated to transmit the rotation of the motor to the rotary shaft. The rotary shaft is positioned at a commanded position using a feedback signal from a rotational position detector irrespective of which one of the two transmission mechanisms is employed.

Abstract: In a DC motor control apparatus for driving a DC motor in accordance with a signal of the difference between a revolving speed signal from a speed detector coupled with the DC motor and a command speed signal so as to drive the DC motor at a revolving speed indicated by the command speed signal, when a voltage to be applied to the DC motor and the revolving speed signal from the speed detector are both detected, the operation of the DC motor control apparatus is decided as normal, and when the voltage to the DC motor is detected but the revolving speed signal from the speed detector is not detected, the operation of the DC motor control apparatus is decided as abnormal and an alarm signal is produced.

Abstract: An automated device comprising an arm, a supporting case mounted on the end of the arm, a rotary actuator mounted on the end of the supporting case and a wrist with a hand rotatably held by the rotary actuator, wherein the rotary actuator has a replaceable stopper on the shaft thereof, and the supporting case has a pair of static members for setting the rotational range of the stopper. In the device, the rotary actuator stops rotating at two positions, i.e., the hand stops rotating at two positions.

Abstract: In a numerical control unit which has an interpolation function from generating command pulses in response to a distribution command and a servo system for driving a movable part of a machine in accordance with command pulses, a comparison is made between the error of the servo system a predetermined period of time after the distribution command is switched off and a preset value; when the error of the servo system is larger than the predetermined value, an alarm signal is produced to detect the occurrence of a malfunction.

Abstract: A system for controlling DC motors of the type employing permanent magnets as field poles. The firing phase angle of a thyristor is controlled in response to an error signal representative of an error between a commanded motor speed and an actual motor speed. For preventing demagnetization of the permanent magnets due to the armature reaction, the clamp level of the error signal is changed in accordance with the actual motor speed.

Abstract: An actual speed N of a DC motor and an armature current Ia are detected to detect the motor output N.times.Ia. The motor speed is changed so that the detected motor output may not exceed a predetermined value. The spark generation of the motor brush is prevented when an over load is applied to the motor.

Abstract: A decoder circuit including: a charge-up transistor for maintaining the content of an input address signal; a power supply switching transistor for controlling a charge-up current which is supplied to the charge-up transistor; a predetermined number of selection transistors which are connected at a connection point between the charge-up transistor and the power supply switching transistor so as to select an output word line, and; a bootstrap transistor which is connected to an opposite side of the connection point with respect to the charge-up transistor. The present invention enables the driving of the charge-up transistor with clock pulses having a potential level higher than the power supply line voltage V.sub.DD. The present invention also enables the driving of the power supply switching transistor by clock pulses having a potential level higher than V.sub.DD +V.sub.th wherein V.sub.+h equals the threshold voltage of the power supply switching transistor.

Abstract: In a tracer control system in which tracer head control is switched over from a quick feed mode to a deceleration mode of operation to alleviate a shock when the stylus of the tracer head contacts the model, the amount of change in the configuration of the model at a profiling start point is detected to control the point of switching over the quick feed mode to the deceleration mode of operation for the next profiling start point in accordance with the detected value, thereby to ensure that the above mentioned mode switching is always accomplished at substantially a constant position relative to the profiling start point on the model surface so as to shorten the profiling time.

Abstract: A numerically controlled machine tool controls the movement of a tool relative to a workpiece along a commanded path to cut the workpiece and to detect a load on the tool or workpiece. A specified position or section on the commanded path is the point at which the load on the tool or workpiece is detected and stored. Subsequently, the load on the tool or workpiece is detected each time the tool passes through the specified position or section and this detected value is compared with the above stored content. When the difference is larger than a predetermined value, an alarm signal is produced to indicate that the tool has worn out.

Abstract: A positioning error, relative to a command value, is premeasured for forward and backward movements of a movable machine part and is set in an error setting means. When the movable machine part is moved in accordance with the command value, the error information set in the error setting means corresponding to the commanded direction of movement is read out to compensate for an error. When the direction of movement of the movable machine part is reversed, integrated contents of the error information, set in the error setting means, are added to the amount of backlash to compensate for an error.

Abstract: A single velocity unit is provided in the control unit of an industrial robot, which control unit has a plurality of motors for driving the arm of the industrial robot and a plurality of detectors for detecting the position of the arm. By the operation of the central processing unit, the digital output unit selects one of the axis position control units and one of the motors to be connected to the velocity unit, in accordance with an axis selecting instruction read out from the memory.

Abstract: A rotary electric machine with a heat pipe for cooling, which pipe comprises a rotary shaft. The rotary shaft has a hole formed therein extending from a heating zone to a cooling zone and has working fluid charged therein. The inner diameter of the cooling zone is smaller than the diameter of the heating zone, and an inner wall of the cooling zone is connected to an inner wall of the heating zone via a step.

Abstract: A numerical control unit in which command data is inputted from a keyboard and stored in an internal memory and which controls a machine tool based on the stored command data. A cassette type memory is constructed to be detachably mounted on the numerical control unit. When the cassette type memory is mounted on the numerical control unit, the command data can be transmitted between the cassette type memory and the internal memory and stored therein and even when the cassette type memory is removed from the numerical control unit, the stored content can be retained. By repeatedly reading out the command data stored in the cassette type memory, the machine tool can be controlled.