With "feed-rate" Control Patents (Class 318/571)
  • Patent number: 4513381
    Abstract: A power tool in which feed rate information is used as a means of changing cutting implement speed to maintain an optimum chip rate removal. As the tool is loaded by a feed rate increase, the motor speed will increase to that point empirically determine to provide a good finish for the material and cutting implement size selected. If the load decreases, the motor speed will correspondingly decrease to that speed which will provide a good finish for the material and cutting implement size selected with out overheating of the material. A limit would be set to indicate to an operator when he is at the upper limit of the speed and feed rate range and turn off the tool after a short period of time to prevent destructive overheating.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: April 23, 1985
    Assignee: The Singer Company
    Inventors: John Houser, Jr., Thomas C. Laughon
  • Patent number: 4510427
    Abstract: A method and apparatus for controlling the feed speed of a machine in a numerical control system having a manual pulse generator for generating pulses in response to a manual operation. The numerical control system numerically controls the machine by supplying the machine with the generated pulses as feed pulses in a manual feed mode and with feed pulses corresponding to a commanded feed speed in modes other than the manual feed mode. The commanded feed speed is modified in accordance with an override quantity stored in a register. The method includes selectively designating the modes other than the manual feed mode, changing the override quantity, which is stored in the register, based on the pulses generated by the manual pulse generator and in accordance with the designated mode, and modifying the commanded feed speed in accordance with the override quantity stored in the register.
    Type: Grant
    Filed: March 25, 1983
    Date of Patent: April 9, 1985
    Assignee: Fanuc Ltd.
    Inventors: Ryoichiro Nozawa, Nobuyuki Kiya, Kunihiko Murakami
  • Patent number: 4509002
    Abstract: Suspending an armature on a parallelopiped basket of flexure springs, with a lateral effect cell position sensor and an X-Y source of motive power, provides a precision X-Y positioner with minimum static friction and with feedback of actual position for closed loop servo operation under computer control. The armature is arranged for X-Y motion within its own plane, and is arranged to carry a gripper, cutting tool, or other end effector. The parallelopiped basket includes a stator, a first set of flexure springs, a flexure spring carrier mounted on the first set of flexure springs, a second set of flexure springs mounted on the flexure spring carrier, and the armature mounted on the second set of flexure springs in turn mounted on the carrier. The basket suspends the armature with freedom of motion in the X and Y dimensions without static friction associated with sliding or rolling motions.
    Type: Grant
    Filed: December 20, 1983
    Date of Patent: April 2, 1985
    Assignee: International Business Machines Corporation
    Inventor: Ralph L. Hollis, Jr.
  • Patent number: 4509127
    Abstract: A control device for loading and unloading mechanism adapted to be incorporated in a fork lift truck comprises a sensor unit 100 including a lifting height sensor 102, a control unit 200 comprising a control command producing circuit 240 constituted by a microcomputer 230 producing a control command on the basis of comparing calculation between the output of the sensor unit 100 and the concerned data stored in the microcomputer 230, and a driving unit 300 producing a driving output signal so as to the lifting height of the fork 18 in accordance with the control command fed from the control unit 200. The control device includes a component operable for inhibiting storage of sampled lifting height data when the actual lifting height data are not within an allowed range, thereby to prevent erroneous operation based on erroneous data and to effect smooth follow-up speed control to the target height when automatic lifting height control is effected.
    Type: Grant
    Filed: March 31, 1982
    Date of Patent: April 2, 1985
    Assignee: Kabushiki Kaisha Toyoda Jidoh Shokki Seisakusho
    Inventors: Katsumi Yuki, Susumu Yoshida, Mineo Ozeki, Yasuyuki Miyazaki, Masaru Kawamata
  • Patent number: 4509126
    Abstract: An adaptive control for a turning machine which adjusts the machining rate to maintain the actual horsepower dissipated at the cutter tip at a constant set point despite changing workpiece and cutter parameters. The machining rate is adjusted by control of the machine drive and tool feed to achieve required SFM and IPR values, respectively, within maximum and minimum SFM and IPR limits. "Speed" and "Axis" override controls are also provided. The rate of adjustment of SFM and IPR to a deviation of the cutter tip horsepower from the set point is inversely proportional to the measured system gain so that the response factor of the control loop is maximized. The cutter tip horsepower is determined by subtracting the electrical loss, mechanical friction loss, and the net power required for net acceleration of the drive, from the measured electrical power supplied to the drive motor. The cutting efficiency is monitored to perform tool wear, tool breakage, and tool protection functions.
    Type: Grant
    Filed: June 9, 1982
    Date of Patent: April 2, 1985
    Assignee: AMCA International Corporation
    Inventors: Eugene A. Olig, Lee R. Ladwig
  • Patent number: 4506714
    Abstract: A lathe for cutting a spiral strip of veneer from the surface of a log includes motor-driven mechanisms for adjusting the knife blade pitch angle and edge height, and for moving a pressure head relative to the knife to adjust the vertical gap and horizontal gap between the knife edge and the roller bar, and provides sensors for determining the actual positions of movable elements of the lathe, thus enabling computer-controlled adjustment of the movable elements of the lathe during lathe operation. A knife clamp of the lathe includes a plurality of separate clamp segments for pressing against different portions of a knife bar to hold it firmly, resisting deformation and rocking of the knife bar. Fluid-pressure-biased bearings eliminate looseness between relatively movable parts of the lathe, reducing the amount of variation of thickness in veneer produced using the lathe. Veneer thickness is controlled by monitoring cumulative movement of the lathe spindles and the main feed carriage.
    Type: Grant
    Filed: April 22, 1983
    Date of Patent: March 26, 1985
    Assignee: Sun Studs, Inc.
    Inventors: Kenneth L. Shrum, Edwin M. Heth
  • Patent number: 4506321
    Abstract: A microprocessor-based motor control system operates the rapid advance motor on a slide transfer machine to carry out rapid traverse motions in minimal time. A velocity profile is stored during the acceleration portion of the move and this data is employed to determine when deceleration should begin and to control velocity during the deceleration portion of the move. A position feedback circuit having programmable resolution is employed to develop the velocity profile.
    Type: Grant
    Filed: September 8, 1982
    Date of Patent: March 19, 1985
    Assignee: IMEC Corporation
    Inventors: Robert H. Comstock, William P. Curtiss, Donald E. Fulton
  • Patent number: 4506335
    Abstract: An articulated manipulator and control are provided for producing controlled motion of a function element carried by the manipulator. The motion is defined by input signals specifying with respect to a rectangular coordinate system the positions and path velocities therebetween of a tool centerpoint associated with the function element. The control interpolates intermediate points along a predetermined path between any two positions. The intermediate points are produced in accordance with a fixed period interval and incremental velocity values instantaneously variable with each interval. Continuous functions of acceleration and deceleration are produced to vary the velocity in accordance with the programmed description of motion. Further velocity adjustment is permitted in accordance with unprogrammed variations of a preselected parameter.
    Type: Grant
    Filed: June 10, 1982
    Date of Patent: March 19, 1985
    Assignee: Cincinnati Milacron Inc.
    Inventor: Timothy J. Magnuson
  • Patent number: 4491777
    Abstract: Linear motors are employed to position fabricating materials in work stations. The fabricating material forms the movable element of the linear motor and the positioning of the fabricating material is precisely controlled by a closed loop positioning control system which drives the stator windings of the linear motor. Two embodiments are disclosed; one for sheet metal and the other for tubular metal.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: January 1, 1985
    Assignee: Unico, Inc.
    Inventors: Thomas L. Beck, Donald B. Lawson
  • Patent number: 4488189
    Abstract: A sector servo seek control samples each sector to obtain sector time, the track identification within a sequence of track types and a position error signal for a track location to track location seek. The device during each sector determines the actual transducer track location and the next sector projected track location with respect to the sequence of track types. The projected track location is corrected using the error signal to find the actual location, but if a sector signal is missing or erroneous, the projected location is used as the actual location, permitting a composite correction to be made when a correct sector signal is obtained. The seek time is minimized by using maximum acceleration followed by maximum deceleration while not exceeding a velocity value that would cause the device to overshoot the target track using full deceleration.
    Type: Grant
    Filed: August 16, 1982
    Date of Patent: December 11, 1984
    Assignee: International Business Machines Corporation
    Inventors: Frederick E. Axmear, Duane W. Baxter, John H. Saxman, Michael M. Siverling
  • Patent number: 4480938
    Abstract: A servomotor drive system for a printer escapement is provided which minimizes power supply requirements. The drive system has means for accelerating and decelerating the printhead escapement having a fixed current source applied to a servomotor which drives the escapement. In order to minimize power requirements, the system includes means for controlling the current in the motor which comprise means for sensing the actual motor current and feeding back the sensed current to a comparing means. A preselected varying current profile is applied to the comparing means which compares this profile to the actual motor current. Means are then provided responsive to these comparing means for altering the actual motor current to conform with this preselected varying motor current profile.
    Type: Grant
    Filed: August 23, 1982
    Date of Patent: November 6, 1984
    Assignee: International Business Machines Corporation
    Inventors: Darryl R. Polk, Richard A. Southworth
  • Patent number: 4478009
    Abstract: An automatic control system for machine tools having rotary tools is disclosed in which the tool drive motor load current, which is proportional to the mechanical load on said drive motor, is maintained at a selectable desired level by controlling the duration and phase of the power supplied to an alternating current feed motor which controls the distance between the rotary tool and the workpiece. A sensed load signal which is greater than the preselected level will cause the feed motor to move the tool away from the workpiece, while a load signal less than that desired will cause the feed motor to move the tool toward the workpiece.
    Type: Grant
    Filed: May 9, 1978
    Date of Patent: October 23, 1984
    Inventors: Daniel M. Rukavina, David H. Arnold
  • Patent number: 4467432
    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.
    Type: Grant
    Filed: May 10, 1982
    Date of Patent: August 21, 1984
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4464866
    Abstract: A system for finish grinding a workpiece monitors the actual radius of the workpiece as the finish grinding progresses; feeds the grinding wheel into the workpiece at a feed rate which decreases, preferably at an exponential rate, as a desired final radius of the workpiece is approached; and terminates the feeding of the grinding wheel at the desired final radius of the workpiece. In a preferred embodiment, the grinding wheel is trued, simultaneously with the finish grinding, by feeding a truing element into the grinding wheel at a rate that varies as a function of the decreasing rate at which the grinding wheel is fed into the workpiece.
    Type: Grant
    Filed: March 5, 1982
    Date of Patent: August 14, 1984
    Assignee: Energy-Adaptive Grinding, Inc.
    Inventors: Roderick L. Smith, Norbert C. Kolell
  • Patent number: 4464614
    Abstract: In a numerical control unit capable of driving a motor at a feed speed designated by a feed speed-designation dial, there are provided a potentiometer for generating a DC voltage proportional to the amount that a feed speed-designation knob is turned and an AD converter for converting the DC voltage output from the potentiometer into a digital quantity, the AD converter output being read out by a main processor section. The circuit construction can be markedly simplified as compared with the conventional circuit construction employing a voltage-controlled variable oscillator.
    Type: Grant
    Filed: March 15, 1982
    Date of Patent: August 7, 1984
    Assignee: Fanuc Ltd.
    Inventor: Mitsuo Kurakake
  • Patent number: 4456962
    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.
    Type: Grant
    Filed: March 15, 1982
    Date of Patent: June 26, 1984
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4455518
    Abstract: A control provision is provided for separating sheets of printed matter. An initiator serves to generate electrical pulses proportional to the transport speed, which are transformed into compensation times depending on the pulses of the operating delay time and of the fall delay time of the servo components, and which are connected to the servo components via coupling elements and following selection or control circuits. A transport means moves the printed material, a distributing guide is operated by the servo components and the sheets to be sorted out are removed independent from the speed of transport and without interference or disturbance of the other sheets.
    Type: Grant
    Filed: December 7, 1981
    Date of Patent: June 19, 1984
    Assignee: Veb Kombinat Polygraph "Werner Lamberz" Leipzig
    Inventor: Claus Drehobl
  • Patent number: 4455512
    Abstract: Movable (a head) and stationary (a stator) members are disposed in contiguous relationship. First magnetizable and non-magnetizable zones are alternately disposed on the stator in a particular direction. Second magnetizable and non-magnetizable zones are alternately disposed on the head in the particular direction. The zones on the head and the stator face each other and have substantially equal spacings. First means are associated with the head for producing magnetic fluxes in the magnetizable zones in the head and stator in a particular pattern to obtain incremental relative movements between the head and the stator on a vectorial basis in the particular direction. Second means are associated with the head for compensating for hysteresis effects in the magnetizable zones in the head and stator. The second means may produce magnetic flux of alternating polarity and decaying amplitude near the end of each incremental movement of the head relative to the stator.
    Type: Grant
    Filed: April 23, 1982
    Date of Patent: June 19, 1984
    Assignee: General Signal Corporation
    Inventors: William J. Cornwell, Tex M. Dudley, William H. Lee
  • Patent number: 4441281
    Abstract: A digital control system for a roll grinding machine controls the infeed of the grinding wheel in a manner which minimizes the impact of momentary changes in infeed command. The momentary change in infeed command which is effectively controlled is that of a pulse compensation introduced for the wear of the grinding wheel.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: April 10, 1984
    Assignee: USM Corporation
    Inventor: Ronald J. Gordiski
  • Patent number: 4441059
    Abstract: A feed rate sensing system for a drilling machine or the like in which a linearly movable cutting tool-supporting block carries a rotatable tool spindle. Linear motion of the supporting block is converted to rotation of a screw and an encoder driven by the screw generates feed pulses representing feeding of the tool toward a workpiece. A proximity switch unit monitors rotation of the tool spindle and produces rotation pulses in relation thereto. A counter and latch circuit produces a digital output representing the feed rate of the tool-supporting block per revolution of the tool spindle and this digital output is converted to a voltage level representing the actual feed rate. A circuit compares such actual feed rate voltage with a desired feed rate voltage, the difference therebetween being applied to a meter.
    Type: Grant
    Filed: November 16, 1981
    Date of Patent: April 3, 1984
    Assignee: Fuji Seiki Machine Works, Ltd.
    Inventor: Mitsuru Watanabe
  • Patent number: 4437046
    Abstract: An extrusion drive control system for control of extrusion process machinery driven elements. A drive interface unit is adapted for use with any of a variety of drive motors and regulators. The interface unit accepts analog condition information signals from the drive motor and regulator, having any of a plurality of predetermined input characteristics, and provides corresponding digital signals having characteristics that are invariant with respect to the particular input characteristics. The interface unit has a communication channel for receiving digital control signals and for outputting digital signals indicating drive operating conditions. The low power digital circuitry and communications channel are protected from the high voltage and high power connections to the drive and drive regulator.
    Type: Grant
    Filed: June 18, 1982
    Date of Patent: March 13, 1984
    Assignee: Crompton & Knowles Corporation
    Inventor: Louie M. Faillace
  • Patent number: 4424570
    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.
    Type: Grant
    Filed: June 10, 1981
    Date of Patent: January 3, 1984
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4419612
    Abstract: An electro-mechanical control system for controlling all of the movements of one or more slides on a single workhead grinding machine. A programmable controller is interfaced with a digital to analog converter or feed control which in turn controls a drive motor that is directly connected to a screw actuator means that directly controls the movements and positions of a slide. The positioning accuracy of the control system is derived from the accuracy of the electronic control components and the stability of the machine. The control system can control the operative movements of each slide in a compound slide assembly, simultaneously or independently, for a part of a grinding machine cycle. The compound slide assembly may alternatively carry a rotating grinding wheel or a workhead that is reciprocated at high speed for a grinding operation on a workpiece.
    Type: Grant
    Filed: January 18, 1982
    Date of Patent: December 6, 1983
    Assignee: Ex-Cell-O Corporation
    Inventors: Kazimierz J. Reda, Victor F. Dzewaltowski, Richard H. Gile
  • Patent number: 4415977
    Abstract: A method for rotating a workpiece at a constant peripheral speed when the workpiece is cut as on a lathe. Before a cutting tool is moved to a cutting position under a rapid-advance command, the number n of RPM for the spindle is computed from the following equation, based on the distance x between the cutting position and the axis of the spindle and based on the commanded periphery speed V for driving the spindle at the computed number of RPM thereof:n=V/2 xAccordingly, the actual peripheral speed of the spindle becomes the same as or approximates the commanded peripheral speed when the cutting tool reaches the cutting position.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: November 15, 1983
    Assignee: Fujitsu Fanuc Limited
    Inventors: Hiroomi Fukuyama, Shinichi Isobe
  • Patent number: 4414495
    Abstract: Apparatus for synchronizing the rotating cutter and rotating workpiece of a gear cutting machine, featuring, in one aspect, correcting synchronism errors due to the time lag between application of a command signal and a corresponding movement of the workpiece by delaying or advancing the command signal by an amount dependent on the time lag and, in another aspect, synchronizing circuits which process pulse-encoded measurements of cutter rotation and axial translation to provide a command signal for driving the workpiece.
    Type: Grant
    Filed: October 27, 1981
    Date of Patent: November 8, 1983
    Assignee: Kashifuji Works, Ltd.
    Inventors: Masaoki Sumi, Tomoyuki Doi
  • Patent number: 4412295
    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.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: October 25, 1983
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4408280
    Abstract: The system is applied to a lathe and allows control of the machine to be adapted in such manner as to make use of the maximum power of the spindle motor with the maximum feed of the tool and the minimum cutting speed. The feed rate and the cutting speed are defined by the programmer only as the permitted region within which these parameters must jointly lie. The control unit tends constantly to command the feed rate and the spindle motor in such manner as to be within this region. Then the control unit compares the power consumed by the spindle motor, which is detected by a circuit through the armature current, with the maximum power of the motor for the actual working conditions and tends to cause the feed rate and the number of revolutions to be adapted in such manner as to make use of this maximum power. The system is adapted to exclude adaptation during cutting-in-air operation.
    Type: Grant
    Filed: October 8, 1980
    Date of Patent: October 4, 1983
    Assignee: Olivetti Controllo Numerico S.p.A.
    Inventors: Raffaele Bedini, Luciano Lauro, Pier C. Pinotti
  • Patent number: 4400781
    Abstract: A numerical controller for a cam grinding machine, which has a cam drive unit and a grinding wheel drive unit, includes a memory for storing profile data of a cam corresponding to angular positions thereof. A data processor is provided for reading out the profile data from the memory so as to generate a rotational speed command indicating a rotational speed of the cam and a feed rate command indicating a feed rate of the grinding wheel at every unit angle rotation of the cam, wherein the rotational speed command and the feed rate command are so decided as to reduce the rotational speed of the cam and the feed rate of the grinding wheel while the side portions of the cam are ground. A pulse distribution circuit is connected to the data processor and responsive to the rotational speed command and the feed rate command therefrom for distributing pulses to the cam drive unit and the grinding wheel drive unit.
    Type: Grant
    Filed: January 27, 1981
    Date of Patent: August 23, 1983
    Assignee: Toyoda Koki Kabushiki Kaisha
    Inventors: Shigeo Hotta, Katsumi Yamamoto
  • Patent number: 4400118
    Abstract: A machine tool including a tool holder supporting a boring tool and receivable in a tool spindle. A device is provided in the tool holder for adjusting the radial position of the boring tool by utilizing rotation of the tool spindle. A contact detecting head with a known predetermined diameter is secured to the tool holder in co-axial relationship therewith. A contact detecting device detects the contact between a workpiece bore and the contact detecting head. A bore diameter measuring device measures a diameter of the workpiece bore by causing relative movement between the contact detecting head and the workpiece from a first position to a second position wherein at each of the first and second positions the contact detecting head contacts the workpiece, along a path passing through the center of the workpiece bore. The tool spindle is rotated in response to the measuring device to adjust the radial position of the boring tool.
    Type: Grant
    Filed: July 9, 1981
    Date of Patent: August 23, 1983
    Assignee: Toyoda Koki Kabushiki Kaisha
    Inventors: Tetsuro Yamakage, Takao Yoneda, Kohsei Imamura
  • Patent number: 4392195
    Abstract: A method of and apparatus for controlledly moving a movable element in a machine tool having a drive unit drivingly coupled to the movable element, a motor drivingly coupled to the drive unit and a motor driver circuit for energizing the motor to drive the drive means, thereby moving the movable element, wherein a sequence of feed signals are furnished from a command source to energize the motor for the purpose of achieving a corresponding and desired sequence of movements of the movable element.
    Type: Grant
    Filed: October 1, 1980
    Date of Patent: July 5, 1983
    Assignee: Inoue-Japax Research Incorporated
    Inventor: Kiyoshi Inoue
  • Patent number: 4388576
    Abstract: An electric servo drive air cylinder includes ported end caps for alternately receiving air from a pressurized source, and a tubular piston rod mounting a piston for intermittent longitudinal reciprocal movements and a projecting rod end for connection to a load. A power rotated reversible ball screw extends through the piston rod and is journaled thereon and upon one end cap and projects therefrom. An axial ball nut is secured to the piston rod and threadedly receives the ball screw. A programmable D.C. motor is mounted upon an end cap and has a drive shaft coupled with the ball screw. An electronic encoder is connected to the ball screw and motor to control direction and number of rotations of the ball screw for effecting a programmed repetitive cycle of predetermined feed movements of the piston rod. A pre-set programmable control is connected to the motor and an electronic encoder feed back circuit which interconnects the encoder and the programmable control.
    Type: Grant
    Filed: September 23, 1981
    Date of Patent: June 14, 1983
    Inventor: Leland F. Blatt
  • Patent number: 4386306
    Abstract: A numerical control device for controlling rotation of a servomotor in response to numerical control data to move a movable member by a commanded feed amount at a commanded feed rate. A velocity detector detects an actual feed rate of the movable member. A register stores an allowable feed rate data. A comparator compares an allowable feed rate data from the register and an actual feed rate from the velocity detector to output an abnormal signal when the actual feed rate exceeds the allowable feed rate. The allowable feed rate data is set into the register each time the commanded feed rate is changed.
    Type: Grant
    Filed: November 6, 1980
    Date of Patent: May 31, 1983
    Assignee: Toyoda Koki Kabushiki Kaisha
    Inventors: Hideo Nishimura, Minoru Enomoto
  • Patent number: 4386305
    Abstract: A motor drive control system for use in a machine tool having spindle and feed shaft motors. If the spindle motor, which is rotating at a constant speed during a machining operation, is subjected to an overload, and consequently experiences a drop in speed, this fact is detected by a detector for detecting the armature current of the spindle motor. The feed shaft motor is slowed down to a predetermined speed if the overloaded condition continues for a prescribed period of time. The feed shaft motor is stopped if an even greater armature current is detected to be flowing due to a continuing overload despite the fact that the feed shaft motor has been slowed to the predetermined speed.
    Type: Grant
    Filed: October 27, 1980
    Date of Patent: May 31, 1983
    Assignee: Fujitsu Fanuc Limited
    Inventors: Yoshinori Kohzai, Yoshiki Fujioka
  • Patent number: 4384333
    Abstract: A control system for a crankshaft-milling or grinding machine having a milling carriage movable in a plane perpendicular to the longitudinal axis of the crankshaft to be machined. A pulse-generating rotary transducer coupled to the workpiece spindle supplies pulses to a computer to indicate both rotary speed and angular position, the computer issuing the requisite control data. The computer is fed pictorial or construction-point data concerning crank pins and crank webs of arbitrary configuration, the computer issuing the requisite control data for feed speed and position after it itself has calculated such data, the data being issued with a clocking rate and updated at such clocking rate at a frequency corresponding to the required degree of dimensional accuracy.
    Type: Grant
    Filed: June 30, 1981
    Date of Patent: May 17, 1983
    Assignee: GFM Gesellschaft fuer Fertigungstechnik und Maschinenbau
    Inventor: Kurt Maecker
  • Patent number: 4379987
    Abstract: A system for controlling the rotation of a spindle includes a motor, a speed detecting circuit for detecting the speed of the motor and for producing a signal indicative of the actual speed thereof, a speed control circuit for controlling the motor so as to narrow to zero a deviation between the actual speed thereof and a commanded speed, a spindle driven by the motor, and a position control circuit for producing a position deviation signal on the basis of a commanded stopping position and the rotational position of the spindle. The spindle is rotated at a commanded speed by the speed control circuit and is rotationally controlled by an orientation command signal so as to make the position deviation signal zero.
    Type: Grant
    Filed: September 25, 1980
    Date of Patent: April 12, 1983
    Assignee: Fujitsu Fanuc Limited
    Inventors: Yoshinori Kohzai, Yoshiki Fujioka
  • Patent number: 4379256
    Abstract: The relative speed of a movable head and a magnetic disc memory for data orded on a plurality of tracks, each having addresses written in a plurality of reference zones, is determined by reading the addresses read with the head at predetermined sampling times. The speed of the head is calculated as a function of the difference between the addresses read by the head and the interval between the sampling times.
    Type: Grant
    Filed: September 11, 1980
    Date of Patent: April 5, 1983
    Assignee: Compagnie Internationale Pour l'Informatique CII Honeywell Bull
    Inventor: Christian Maury
  • Patent number: 4371941
    Abstract: A digital control system is provided for positioning a tool relative to a workpiece. The tool is preferably a grinding wheel and the workpiece is a roll appropriately mounted within a roll grinding machine. The digital control system receives various infeed commands representative of the different types of infeed positioning that are to be performed during a grinding operation. The digital control system is thereafter operative to combine these infeed commands into a composite set of control signals. These control signals are applied to a single motor within a pivotal infeed arrangement which moves the grinding wheel relative to the workpiece.
    Type: Grant
    Filed: December 31, 1979
    Date of Patent: February 1, 1983
    Assignee: USM Corporation
    Inventors: Ronald J. Gordiski, Robert G. Bennett, Jr., Alfred T. Parrella, Michael Bagnall
  • Patent number: 4370704
    Abstract: A feed speed control system for use in numerical control systems or the like, in which a set feed speed can be adjusted through a simple structure. The control system includes a memory circuit for storing a plurality of numerical values corresponding to feed speeds, a command circuit for issuing a command indicative of a prescribed numerical value from among the plurality of numerical values, an arithmetic circuit for incrementing or decrementing a numerical value read from the memory circuit in response to an output pulse from manual operation device, and a pulse generating circuit for generating pulses of a frequency which is proportional to an incremented or decremented numerical value from the arithmetic circuit.
    Type: Grant
    Filed: September 2, 1980
    Date of Patent: January 25, 1983
    Assignee: Fujitsu Fanuc Limited
    Inventors: Hiroomi Fukuyama, Shinichi Isobe
  • Patent number: 4370722
    Abstract: Data for determining a limit value of the trace range of a model are stored in a memory and the stored data are read out therefrom by a processor to calculate the limit value of the trace range. The current position of a movable machine part is detected and compared with the limit value and when it is detected by the processor that the current position of the movable machine part has reached the limit value, a trace feed is switched to a pick feed. After the pick feed is performed a predetermined distance, it is switched again to the trace feed. A desired trace range is set to achieve tracer control without the provision of limit switches.
    Type: Grant
    Filed: January 5, 1981
    Date of Patent: January 25, 1983
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki, Takao Sasaki
  • Patent number: 4359676
    Abstract: A control system for stopping a spindle at a predetermined rotational position, for driving a spindle in such a manner that a positional deviation between the present rotational position of a specified point on the spindle and a predetermined rotational position at which the specified point is to be stopped, is reduced to zero, thereby to stop the specified point on the spindle at the predetermined rotational position. First and second rotational position sensors are attached to the spindle at first and second specified points thereof, the position at which at least the first rotational position sensor is attached being adjustable. Further provided are changeover means and an orientation control circuit. The first position sensor produces a rotational position deviation signal when a tool is inserted into and withdrawn from a workpiece at the time of a boring operation, and the second position sensor produces a rotational position deviation signal when tools are changed.
    Type: Grant
    Filed: December 12, 1980
    Date of Patent: November 16, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventor: Yoshiki Fujioka
  • Patent number: 4357664
    Abstract: In one forward or backward trace path on a model, a jerk point in the surface configuration of the model is detected and the position of the jerk point is stored in a memory. The reduction of the trace velocity is started a predetermined distance short of the stored position of the jerk point in the trace direction and when a jerk point is detected again, the position of the jerk point previously stored in the memory is updated and the reduction of the trace velocity is released, thus achieving high accuracy trace.
    Type: Grant
    Filed: September 25, 1980
    Date of Patent: November 2, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Takao Sasaki, Etsuo Yamazaki
  • Patent number: 4356552
    Abstract: In a tracer control system, parameters necessary for a trace operation, such as, for example, tracer head reference displacement value, trace axis, trace direction, pick feed value, and various limits, are set in combination for each trace mode. A character display is provided for displaying various parameters, so that it is easy to confirm each of the required parameters corresponding to a selected trace mode, and check whether the setting of all required parameters has been completed or not and whether the value of each set parameter is the desired one or not.
    Type: Grant
    Filed: March 19, 1980
    Date of Patent: October 26, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4355362
    Abstract: In a system which performs tracer control by calculating the direction and the velocity of tracing through utilization of 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 processor for reading out the data from the memory to control respective parts of a control device. Data concerning clamp tracing is read out by the processor to change the clamp level by a predetermined value for each working, thereby performing repetitive clamp tracing.
    Type: Grant
    Filed: March 17, 1980
    Date of Patent: October 19, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4353018
    Abstract: An improved control system for facilitating tapping work in a machining center of the type which performs a variety of machining operations automatically. Control is effected by establishing and maintaining a certain relationship between the operation of a spindle motor which rotates a tap, and the operation of a Z-axis feed motor which transports a table longitudinally of the tap, the table mounting a workpiece. Specifically, the spindle motor and Z-axis feed motor are driven in relation to one another at all times in such a manner that the equation N.sub.s =f.sub.m /P will be satisfied, where N.sub.s (rpm) is the rotational speed of the spindle motor, f.sub.m is the feed speed of the table along the Z-axis, and P is the thread pitch of the tap. Apparatus for controlling the spindle motor includes a control circuit which is adapted to stop the spindle at a prescribed angle of rotation.
    Type: Grant
    Filed: August 20, 1980
    Date of Patent: October 5, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventors: Yoshinori Kohzai, Yoshiki Fujioka
  • Patent number: 4346444
    Abstract: A metal working machine for moving a cutting tool through a metal workpiece which includes a spindle carrying a cutting tool therein, a feed drive motor for advancing the spindle, and a rotation drive motor for rotating the spindle. The workpiece is firmly held by a variable force clamp in an operative position to permit the cutting tool to move therethrough. The thrust of the cutting tool is sensed as well as the rotational velocity of the spindle. A data memory contains the optimum thrust load against a predetermined workpiece material for a cutting tool having a predetermined diameter dimension.
    Type: Grant
    Filed: March 20, 1980
    Date of Patent: August 24, 1982
    Assignee: Rohr Industries, Inc.
    Inventors: Samuel Schneider, John D. Beyer
  • Patent number: 4334272
    Abstract: In a system which performs tracer control through the use of a displacement signal of a tracer head tracing the surface of a model, there is provided: a first coordinate conversion circuit in which signals representative of the cosine and sine of the azimuth angle of the feed axis in the X-Y plane of a mechanical coordinate system and X- and Y-axis displacement signals of the tracer head are respectively multiplied by multipliers and the output signals from the multipliers are added together to thereby obtain a displacement component signal of the feed axis; and a second coordinate conversion circuit in which a signal for controlling the feed rate in the feed axis and the signals representative of the cosine and sine of the azimuth angle of the feed axis are respectively multiplied by multipliers to obtain feed rates along the X- and the Y-axis.
    Type: Grant
    Filed: February 4, 1980
    Date of Patent: June 8, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventors: Ryoji Imazeki, Etsuo Yamazaki
  • Patent number: 4332492
    Abstract: In a printer comprising a printing head, which is supported by a carriage, the carriage position along a record carrier is sensed at two occasions. A cooperating micro processor calculates an actual carriage speed on the basis of the position values which are obtained. The actual carriage speed and an optimal carriage speed, which is stored, are compared and on the basis of this comparison a compensation factor is calculated for a reference signal (Ref) which determines the carriage speed. This compensation factor is checked at each carriage movement by measuring the carriage speed. Accordingly a permanently optimal carriage speed is secured and the need of an accurate trimming of the carriage speed is eliminated during manufacture as well as at later service periods.
    Type: Grant
    Filed: September 19, 1979
    Date of Patent: June 1, 1982
    Assignee: U.S. Philips Corporation
    Inventors: Rolf A. B. Thern, Peter Dahlberg
  • Patent number: 4330832
    Abstract: A method of, and apparatus for, controlling the feed rate of a cutter in a machine tool of the type in which a spindle is rotated by an electric motor having operating regions of constant torque and output characteristics so as to render constant the circumferential speed of a workpiece while the workpiece is subjected concurrently to a machining operation by moving a cutter into contact therewith. The apparatus includes mechanism for computing the maximum cutter feed rate, the circumferential speed V.sub.c of the workpiece, the cutting width d of the cutter and the maximum cutting quantity Q.sub.max which is decided by the maximum power P.sub.max of the motor, mechanism for computing a spindle speed N.sub.s from the circumferential speed V.sub.c and the outer diameter D of the workpiece, mechanism for comparing the magnitudes of a base speed N.sub.b and the spindle speed N.sub.s, where the base speed N.sub.
    Type: Grant
    Filed: March 7, 1980
    Date of Patent: May 18, 1982
    Assignee: Fujitsu Fanuc Limited
    Inventors: Yoshinori Kohzai, Shigeki Kawada, Yoshiki Fujioka
  • Patent number: 4328449
    Abstract: A device for controlling the speed of movement of a mobile member relative to a fixed support member, said mobile member receiving its motion from first drive means is described. The main feature of said drive is that it comprises a speed transducer operated directly by said mobile member and arranged to supply an electrical signal proportional to said speed of movement of said mobile member to second comparison and processing means, to said second means there being also fed at least one electrical reference signal proportional to a predetermined value of said speed; the output signal of said second means, proportional to the difference between said signal of said transducer and said electrical reference signal, being fed to said first drive means.
    Type: Grant
    Filed: December 13, 1979
    Date of Patent: May 4, 1982
    Assignee: Fratelli Sandretto S.p.A.
    Inventor: Mario Calligaris
  • Patent number: 4325013
    Abstract: A control for a profiling machining tool, and a method for controlling such a tool. The machine tool includes a sensing head which moves along a template or pattern to produce a signal that causes motors relatively to shift a cutting tool and a workpiece so as to duplicate in the workpiece the profile of the template or pattern. Two sinusoidal signals are generated as a consequence of stylus deflection along orthogonal axes. They are combined to form a single sinusoidal signal which is then variously processed to produce an error signal which causes the motors to operate in directions which tend to reduce the error signal, and to cause the stylus automatically to move along the profile while doing so.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: April 13, 1982
    Inventor: Robert H. Wenzel