Abstract: A machine interface circuit for controlling terminal units such as relays, switches and the like of a machine tool through a numerical control unit is disclosed. The machine interface circuit comprises an interchange circuit (11) connected to the numerical control unit (1) through a serial interface; and module circuits (20, 40) connected to the interchange circuit (11) through serial interfaces, each module including a serial/parallel conversion circuit (30, 50) and drivers (21a) and/or receivers (41a). According to the present invention, the machine interface circuit transmits parallel signals over a short distance and includes cables and cable bundles having a simple construction.

Abstract: A numerical control device having a non-volatile, large-capacity magnetic bubble memory and a volatile, high-speed integrated circuit memory as memories for storing machining program data. Machining program data which has been stored in the magnetic bubble memory is transferred to and stored in the integrated circuit memory through an interface circuit by introducing power from a power source, the interface circuit functioning to administer the transfer of the data between both of the memories. Numerical control processing is executed by allowing a processor to access the integrated circuit memory.

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: 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: The direction of pick feed is determined by a feed-direction signal produced based on the result of decision by a phase decision circuit and the direction of pick feed inputted from an input unit, and the pick feed is effected by a contour trace. In the case of tracing a hemispherical model, the pick feed can be achieved in a plane parallel to the X-Y plane. The feed-direction signal indicates whether the direction of tangential velocity is to be +90.degree. or -90.degree. with respect to the normal direction. A velocity arithmetic circuit inverts the polarity of its output, a tangential-direction velocity signal, depending on the binary value of the feed-direction signal. Motors are driven by the outputs from amplifiers selected by a gate circuit, by which, in the case of tracing the hemispherical model, the pick feed plane is made to correspond to that in the case of a contour trace, wherein the pick feed can be effected in a plane parallel to the X-Y plane.

Abstract: A clamping tracer control system which performs a tracing feed and a pick feed alternately and effects a clamping feed at a preset clamp level and in which, between the pick feed position where the clamping feed is carried out first and the pick feed position where the clamping feed has been completed, tracer control is repeated while changing the clamp level sequentially, and when the clamping feed has been completed in the repeated tracer control, the clamp level is restored to its area of initial value to resume tracer control of the tracing feed and the pick feed alternately in the next area.

Abstract: In a system which performs tracer control by calculating the direction and velocity of tracing using signals from a tracer head tracing the model surface, there are provided an input unit for entering data defining the tracing operation, a memory for storing the data and a processor for reading out the data from the memory to control respective parts of a control device. Of the data defining the tracing operation, stored in the memory, data concerning the reference displacement of the tracer head is read out by the processor to change the reference displacement for each profile modeling operation, thereby automatically performing repetitive tracing.

Abstract: In a power source device for a bubble memory unit consisting of a bubble memory part and a control part, a controlling supply voltage to be applied to both the bubble memory part and the control part is produced by a power source circuit based on a pulse width modulation system. The power source circuit is provided with a circuit which can expand the signal pulse width in excess of its upper-limit value during the ordinary voltage control. When the controlling supply voltage has become lower than a predetermined value, the pulse width is expanded so that the refresh operation may be perfectly executed when the power source device for the bubble memory unit is turned off.

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: A portable bubble memory apparatus having a bubble memory cassette for accommodating a bubble memory element, and a portable cassette adapter provided with a cassette holder for loading and unloading the bubble memory cassette, the portable cassette adapter housing a control circuit and peripheral circuitry for the bubble memory element. A signal generator generates a signal to indicate whether the bubble memory cassette has been loaded at the correct position within the cassette holder. If the bubble memory cassette is displaced from the correct position, the generated signal causes the exchange of information between the bubble memory cassette and an external unit to cease.

Abstract: A three-dimensional tracer control system which is provided with an integration circuit for integrating the difference between a Z-axis direction displacement signal and a reference displacement signal and an adder for adding together the above-mentioned difference and the output from the integration circuit. The trace velocity in the Z-axis direction is controlled by the output from the adder, by which it is possible to perform tracing, with the Z-axis direction displacement signal and the reference displacement signal held nearly equal to each other; consequently, machining accuracy is increased.

Abstract: A tracer control system which performs tracer control based on a displacement signal from a tracer head tracing the surface of a model and is equipped with the function of freely setting the infeed of a cutter for machining a workpiece. The tracer control system is provided with a first drive system for feeding the tracer head in the Z-axis direction, a second drive system for feeding the cutter head in the Z-axis direction, first and second position detectors for detecting the positions of the tracer head and the cutter head in the Z-axis direction, and a superimposing circuit for superimposing on each other a position detection signal from the first position detector and an infeed command signal for setting the infeed of the cutter head. The cutter head is fed by the second drive system in the Z-axis direction so that the difference between output signals from the superimposing circuit and the second position detector may be reduced to zero.

Abstract: A method and apparatus for numerically controlling a machine tool having at least two tools which are arranged to move in unison with a constant position relationship with respect to one another, the tools being moved relative to a workpiece in accordance with absolute commands to machine a workpiece in a prescribed manner. A single current position register, comprising a section for storing X coordinates and a section for storing Z coordinates, is provided to store the current position of a first tool. Further provided are arithmetic means, responsive to a command for setting coordinates, for computing the current position of a second tool, as well as pulse distribution means.

Abstract: In a tracer control system which controls tracing based on displacement signals from a tracer head tracing the surface of a model, there are provided position detectors for detecting the positions of a tracing machine along the X, Y and Z axes and angle correcting means. The difference between a set trace direction and the actual trace direction detected by the position detectors is obtained for every other fixed distance of movement along the X-axis or Y-axis direction and a trace velocity along the X-axis or Y-axis direction is corrected by the angle correcting means so that the above difference may be reduced to zero, thereby controlling tracing to be performed in the set trace direction.

Abstract: A programmable sequence controller which enables display of the contents of a storage means for storing input and output data to and from a machine, and which permits numerical values to be set in the storage device from an external unit. The programmable sequence controller utilizes a sending and receiving unit for an exchange of commands and other data with a numerical control device in order to transfer display content and numerical values which have been set. This allows the contents to be displayed on display means provided in the numerical control device, and permits the setting of numerical values which are entered from a data setting means provided in the numerical control device.

Abstract: In a tracer control equipment which calculates a trace direction and a trace velocity using signals from a tracer head tracing the model surface and performs tracer control in accordance with the calculation results, there are provided a memory for storing numerical command data and means for reading out the numerical command data by a processor from the memory, whereby to add a numerical control function for positioning control to the tracer control equipment.

Abstract: A programmable sequence controller which need not be equipped with a tape reader for reading a paper tape bearing a punched sequence program or the like. A prepared sequence program or the like is punched in a paper tape in accordance with the standards of a paper tape reader which is provided in a numerical control device, and then is transferred from the numerical control device to a random access memory in the programmable sequence controller. The sequence program is read from the random access memory to permit the execution of sequential operations by processing the program.

Abstract: A method of preparing and executing a sequence program for effecting the sequence control of a sequence controller for a machine tool by executing a subroutine program. A sequence diagram is prepared, which diagram expresses a function command for a subroutine as data divided into control conditions and parameters. From the sequence diagram a sequence program is prepared, which program includes a command for reading data indicative of a control condition, and parameter data of which a subroutine is informed. The sequence program so prepared is then executed.

Abstract: A method and system for rewriting data in a non-volatile memory of the type which requires a comparatively long period of time for the rewriting of stored data. The occurrence of an interruption in power can be detected on the basis of the content of the non-volatile memory, and detection takes place after the resumption of power even if the interruption in power takes place during the rewriting operation. The non-volatile memory is provided with a flag area in which information indicating the initiation of a modification is written prior to the rewriting operation, and in which information indicating the termination of a modification is written after the rewriting operation, whereby an interruption in power which has occurred during rewriting is readily detected by reading out the information from the flag area after the restoration of power.

Abstract: During a tracing operation of a tracer head for detecting the surface configuration of a model, the current position of the tracer head in the Z-axis direction is detected and a maximum value of the detected tracer head positions is stored in a memory means. When the tracer head is returned from a trace terminating end to a trace starting end, it is quickly returned to a position corresponding to the sum of the stored maximum value and a constant value.