Abstract: A reference point detection pulse generator determines normally-equidistant reference points which provide references over the whole control axis range of a numerically controlled machine. On the basis of the outputs of the reference point detection pulse generator and a moving amount detection pulse generator, the position of a moving part is numerically calculated by a moving part position calculator means. The position of the moving part based on the output of the moving amount detection pulse generator is compared with that based on the output of the moving part position calculator means, and if an error is present therebetween an alarm is issued.

Abstract: An electrical duplicating control apparatus, in particular a duplicating milling machine, having a sensing stylus which can be deflected in three dimensions with three sensing systems in which the amount of spatial deflection of the sensing stylus is held constant by means of a deflection control acting on the feed rate control and in which the sensing stylus deflection and the travel velocity can be varied independently of each other.

Abstract: A computer numerical control system for controlling a lathe or similar machine tool in the cutting of threads. One computer is used as an interpolator to produce speed commands in real time for producing a smooth cutting tool motion. A second computer is used as an axis controller for receiving said speed commands and for controlling the servo circuits of up to six machine tool axes. A resolver attached to the rotating spindle is utilized to synthesize a tachonometric signal, and is also connected to an interrupt circuit to measure the spindle speed and position. The interpolator then uses this spindle information to synchronize the cutting tool motion with the spindle angular speed and position to enable multiple passes of the cutting tool along the same thread line.

Abstract: Prior art adaptive control systems for numerically-controlled milling machines are first discussed in which N/C instructions and adaptive control system data are obtained and stored in a storage medium utilizing a software routine which takes into consideration parameters of the milling process and parameters of a specific milling machine. The instructions and data command, for sequential steps in the milling process, such items as spindle position, feedrate and reference milling forces and are supplied to an N/C unit and to the adaptive control system at the milling machine to automatically control the milling process. The adaptive control system includes a milling force sensor and functions to override the commanded feedrate on comparison of the actual milling forces during the process with the reference milling forces.

Abstract: A system for accepting commands of the number of steps in a movement and for producing motion commands in a motion system that divides the movement into the number of steps in successive time intervals with the motion commands consisting of altering the number of steps between adjacent time intervals that are required to produce the movement.

Abstract: A plotter system is provided having an adaptive velocity means for improving plotted line quality by selectively varying the velocity of the plot head to produce smooth, substantially continuous motions of the plot head between data points, in accordance with changes in the data input rate or changes in the distance between data points. This reduces the time that the plot head remains stationary during plotting, thereby reducing excess deposits such as ink pools that may be applied to a portion of a surface when the plot head becomes stationary waiting for data. The system includes a motor unit, a plot head with a pen, and an adaptive velocity means comprising a random access memory (RAM) unit for storing data values to be plotted, a processor unit, and a read only memory (ROM) unit having a stored routine. The plot head is driven by the motor unit under control of the processor operating in accordance with the stored routine and control and data values stored in the RAM.

Abstract: An apparatus is provided for moving a machine element along a straight line path in a plane defined by two orthogonal axes of motion. A switching device is provided for producing an input signal representing the slope of the straight line path which is defined by the tangent of the angle formed between the path and a first axis of motion. In accordance with mechanisms known in the prior art, first output pulses are generated for moving the machine element along the first axis of motion at an arbitrary velocity. The invention provides a counter circuit having a modulus as a function of the component of slope along the first axis of motion. Further in response to the input signal and each of the first output pulses, the counter circuit increments a number of times represented by the component of slope along the second axis of motion.

Abstract: Apparatus and method for cycling elements of a tracer mechanism-controlled machine tool in a trace cut along a selected tracing plane defined by first and second mutually perpendicular axes under control of two power control means respective to the selected axes, and at the end of the trace cut, selecting a pick plane for pick movement, which pick plane includes one of the previously-selected axes and a third axis which is normal to the first and second axes, accomplishing the pick movement under control of two power control means respective to the axes which define the pick plane, and after distance measuring means has indicated completion of a predetermined travel along the third axis, to terminate the pick movement and again select the first two selected axes for a trace cut in a direction opposite to the first trace cut. Machine tool elements are moved by motor means responsive to the power control means.

Abstract: A machine tool having an electrical means for producing a non-cylindrical surface of revolution.

Abstract: A control apparatus for a machine tool having a tool support supporting a tool for machining a workpiece and movable relative to the workpiece through a feed screw is disclosed. When the tool support is moved to a position in the vicinity of an original position, a signal indicator generates an output signal. In response to the output signal, one of reference pulses generated in response to the relation of the feed screw is specified to define the original position. A digital switch sets a distance between the original position and a start position. The tool support is moved toward the workpiece by the distance set by the digital switch from the original position defined by the specified reference pulse.

Abstract: The stack of sheets is moved towards the distributor at a control velocity corresponding to the distributor operation. If the stack in the operative vicinity of the distributor becomes too low, indicating too slow a stack advance, a mechanical sensor sensing the position of the top of the stack rotates to a position interrupting the signal furnished by the first and second inductive input signal generator. The interruption of the signal results in the furnishing of a second sensor output signal which, at a time determined by a synchronizing signal sets a monostable multivibrator whose output then energizes a relay which in turn applies voltage to a winding of a servomotor moving the arm of a potentiometer in a direction for increasing the speed of advance of the stack.

Abstract: A feed rate control system for a numerical control system comprising a circuit to produce a unit movement quantity .DELTA.S and a unit feed rate .DELTA.F, a circuit to accumulate the unit feed rate .DELTA.F at each pulse of the pulse generator and to store them, a ratio calculator to obtain the ratio M of the output numerical value .SIGMA..DELTA.F to said unit movement quantity .DELTA.S, multipliers MUL.sub.1, MUL.sub.2, and MUL.sub.3 to multiply said unit movement quantity .DELTA.S, a Z-axis increment .DELTA.Z of said unit movement quantity .DELTA.S and a X-axis increment .DELTA.X, respectively, by said ratio calculator output M, and a circuit to compare the output numerical value .SIGMA..DELTA.F of the storage circuit with the unit movement quantity .DELTA.S and to produce an accumulating signal t whenever said .SIGMA..DELTA.F is larger than said .DELTA.S, said accumulating signal controlling t the feed rate of the machine tool, which is provided with a high feed rate circuit.

Abstract: An improvement in a logic controlled sewing machine which permits an operator to vary by electronic means ornamental pattern bight and feed, manual stitch control, or individually control forward and reverse feed to achieve, for example, an optimum balanced buttonhole or ornamental variations to patterns. Operator influenced means are effective to signal the logic to apply a holding signal to FET switches, maintaining the FET switch in the conductive state. Closing of the FET switch inserts the wiper of a rheostat in bypass arrangement in the feedback circuit of an operational amplifier between a digital-to-analog converter for feed or bight and, respectively, a feed or bight servo amplifier system. By changing the magnitude of the resistance in the feedback circuit of the operational amplifier, the gain may be altered, thereby to control the signal to the feed or bight linear actuator for variation of stitch length or pattern width, respectively.

Abstract: A control system for controlling the relative movement of a head member over a surface such as a plate member in accordance with digital input information. The head member and the surface form a linear, two-axis synchronous motor and the input signal to the head member is controlled to be a translating field vector to produce movement of the head member relative to the surface. The phase of the translating field vector is controlled to lead or lag the position vector of the surface by an electrical angle which is a direction function of the acceleration or deceleration required. An initial acceleration is used to bring the head member up to the desired terminal speed as quickly as possible and with the head then moved at a constant speed until a point when a signal is applied to produce a deceleration to slow down the head so that the head may be stopped at the position on the surface. Additional acceleration and deceleration vectors are provided to control the movement of the head member.

Abstract: Apparatus is described for the controlled mixing of liquids in a predetermined ratio and is especially suitable for the dispensing of predetermined ratios of polyol and polyisocyanate liquids in the liquid injection molding of polyurethane articles. The ratio control is achieved by a master-slave velocity relationship between at least two metering pumps of the plunger or piston type which are velocity coupled and inject on a common programmed velocity profile that is fed into the pump control that is the master system. Each pump control system has a velocity feedback control loop (a closed loop system) and one signal into the slave automatic control system (typically the polyol system) is obtained in a suitable ratio from the feedback master automatic control system (typically the poly isocyanate system).

Abstract: A converter converts numerical data of unit length indicating instructions for moving a component in directions of first and second coordinates to a number of pulses of minor resolution. An interpolator coupled to the converter interpolates the pulses of minor resolution to provide distribution pulses of minor resolution. A mover coupled to the interpolator moves the component in directions of one of the coordinates in minor resolution. A divider coupled to the interpolator converts the number of pulses of minor resolution to the lesser number of pulses of major resolution and a mover coupled to the divider moves the component in directions of the other of the coordinates in major resolution.

Abstract: A method for regulating the material feed to a processing machine, particularly a comminuting machine wherein the actual value of the temperature of the motor winding or windings is measured with the aid of a temperature sensor and is compared in a control regulator with a predetermined theoretical or reference temperature which lies somewhat below the maximum permissible winding temperature of the motor. The difference between the actual value and the reference value effects production of a signal which is applied to an auxiliary regulator for comparison with the actual motor current to derive a reference speed signal for comparison with the actual speed of the aggregate feed conveyor for adjusting aggregate feed.

Abstract: The system includes a pair of stepping motors for controlling relative movement of the wire electrode relative to the workpiece with the velocity of movement being controlled as a function of gap voltage. For this purpose the system includes a voltage controlled oscillator having its input coupled to the machining gap and its output interconnected with the drive circuits for the two stepping motors. The system further includes a divider stage which becomes operable in the system responsive to drop of voltage indicating gap short circuit condition so that a drastically reduced number of stepping pulses are provided to the motors throughout the duration of the gap short circuit condition. After removal of the gap short circuit condition, an increase in voltage allows changeover through several different gating stages to again return the output of the voltage controlled oscillator to its normal frequency range so that the feed of the electrode relative to the workpiece is again continued.

Abstract: A motion control system and method that subdivides a movement into commands for sequential lengths that the system is to produce in sequential constant time intervals with each time interval having a length. Each length has an extent in steps along each axis and the difference in the number of steps between adjacent extents is limited to that which the motor's ability can accommodate. Each command directs the selection of a present extent with the quantity of a command being reduced by commanding only the difference between the present extent and the immediately prior extent. For essentially constant velocity contouring along two axes an endless sequential series of essentially constant length vectors is provided and each command for a present vector directs the selection based on the relation between it and the prior selected vector. Selection may be made from a number of series of vectors each having a different size.

Abstract: Numerical control apparatus for a lathe which reads from an input medium data specifying the transverse and axial position of the cutting edge of a lathe tool with respect to the axis of the workpiece being machined, the cutting rate for the tool, and the rate of advance of the tool. The apparatus includes processing means responsive to the data for generating a continuous transverse position datum for the tool and computing means controlled by the cutting rate datum and the continuous transverse position datum for controlling the rotational speed of the mandrel of the lathe.

Abstract: A machine for forming gears and the like comprises a workpiece support continuously rotatable about a first axis, a tool support angularly displaceable about a second axis and constructed to support a tool for rotation about a third axis angled to the first axis and an electrical master-slave servo system having a master providing a first electrical signal defining a required angular displacement for the tool support and a second electrical signal for influencing the continuous rotation of the workpiece support in dependence upon the angular displacement defined by the first signal.

Abstract: A system is disclosed for a sewing machine in which preselected stitch patterns may be formed automatically. Information related to the positional coordination of the needle penetration for each stitch of each pattern is stored in the sewing machine. Logic means are used to select and release said stitch information in timed relation with the operation of the sewing machine. The selected information is converted to positional analog signals which control closed-loop servo means including a moving-coil linear actuator which directly controls the position of conventional stitch-forming instrumentalities of the sewing machine to reproduce a pattern of stitches corresponding to the selected stitch information.

Abstract: A velocity-change control system and method are described for numerical control machines enabling the programming of higher speeds of operation for curved and straight-line paths while reducing positional errors and maintaining the acceleration and deceleration at a prescribed value. The system includes a hardwired digital logic unit for each axis interposed between the axis path generator and the axis drive. The input to each axis unit corresponds to the programmed path and velocity and is in the form of electrical pulses each representing a small fixed increment of motion for the particular axis. The output is in the form of pulses representing the same resolution of motion as the input pulses but providing an output trace which lags the input trace by a distance related to the path velocity.

Abstract: An apparatus for maintaining a constant surface speed of a rotating work piece being cut by a moving cutting tool, comprising means for storing a first signal representing a binary coded decimal number which is further representative of the product of the desired constant surface speed of the work piece and a conversion constant. The apparatus is further comprised of a shift register for receiving a second signal representing a binary coded decimal number which is further representative of the current radial dimension of the work piece being cut, and means for storing a third signal representing a binary coded decimal number initially representative of an assumed rotational speed of the work piece.

Abstract: An apparatus for a machine tool for the automatic generation of a switching signal and for reducing the speed of a tool from the advance feed stroke into the work stroke upon approach of the tool at the workpiece. The invention contemplates mechanism for accelerating the tool opposite to the feed direction or stroke and which upon approaching of the tool at the workpiece is electrically actuated by the switching signal.

Abstract: A feed control device is disclosed for controlling the feed speed of a tool relative to a workpiece to be machined. The device includes a load detector for generating an output signal in response to a load applied to the tool, a circuit responsive to the output signal generated by the load detector when the load is higher than a predetermined value for successively decreasing the feed speed until the load reaches the predetermined value, and a circuit responsive to the output signal generated by the load detector when the load is not more than the predetermined value for successively increasing the feed speed until the feed speed reaches a predetermined value.

Abstract: Programming positioning apparatus is described for performing a programmed motion in a quick and smooth manner avoiding shock loads that shorten equipment life.The described apparatus is a hard-wired digital system which is preprogrammed with respect to maximum acceleration and maximum velocity; receives the programmed distance data, makes the required calculations relating to the time periods the system operates according to a maximum acceleration mode, a maximum velocity mode and a maximum deceleration mode in order to perform the programmed motion at maximum speed while keeping the acceleration forces within acceptable limits; and produces motion command pulses supplied to the drive. The maximum acceleration can be held to a constant value fixed beforehand, or can be varied so that the acceleration will automatically adapt itself to produced inertia-forces or to the capability of the motor to drive its load.

Abstract: A digital position control for linearly moving apparatus driven by a motor includes a command signal generating loop coupled to a motor operative condition control loop. The command signal generating loop provides a digital pulse train signal having frequency characteristics corresponding to the desired accelerations and velocities of the apparatus and a total number of pulses proportional to the desired movement of the apparatus. The motor operative condition control loop employs the command signal to energize the motor in accordance with the frequency and pulse count characteristics of the command signal.

Abstract: A lathe numerical control system for cutting a tapered thread by a cutting tool that is moved along a rotating workpiece in steps on both a lead axis and a radius axis. Synchronism of movement along both axes with the workpiece rotation is achieved by an encoder producing a set number of pulses per revolution of the workpiece and these pulses are directed simultaneously to a lead axis path and a radius axis path with each path effectively dividing its encoder pulses to produce the steps needed for the tool movement to produce a thread for each revolution.

Abstract: A simple method and apparatus is disclosed for the calibration of a numerically controlled milling machine or the like, to determine the compliance for a particular set-up of the machine. The apparatus includes a hydraulic cylinder mounted on the machine bed, with the end of the hydraulic piston bearing against a non-rotating cutting tool that is mounted in the spindle. A pressure gauge or pressure switch indicates fluid pressure in the hydraulic cylinder to determine force of the piston on the cutting tool, and a deflection sensor measures the static deflection of the spindle. In one apparatus, hydraulic fluid from a high pressure source passes through a pressure-reducing valve into the rear of the hydraulic cylinder to push the piston rod end against the cutting tool, without requiring motion of the spindle relative to the bed, the valve being adjusted to maintain a desired fluid pressure behind the piston despite leakage of fluid past the piston.

Abstract: Method and apparatus for numerical control to produce contouring by simultaneous coordinated motions along two or more axes, characterized by the creation of desired velocity signals supplied as the primary inputs to velocity servos coupled to drive a member relatively along the respective axes. Although capable of practice by and susceptible of embodiment in other apparatus, a digital computer is physically organized and conditioned by a master program, and associated with an adjustable interrupt clock which measures off successive time periods .DELTA.T, so as to supply a changeable velocity command number signal to each servo proportional to the distance per .DELTA.T through which motion along the associated axis is to occur. This velocity command number is algebraically added to a theoretical position number to signal dynamically during each period .DELTA.

Abstract: Method and apparatus for numerical control to produce contouring by simultaneous coordinated motions along two or more axes, characterized by the creation of desired velocity signals supplied as the primary inputs to velocity servos coupled to drive a member relatively along the respective axes. A digital computer associated with an adjustable interrupt clock which measures off successive time periods .DELTA.T, supplies a changeable velocity command number signal to each servo proportional to the distance per .DELTA.T through which motion along the associated axis is to occur. This velocity command number is algebraically added to a theoretical position number to signal dynamically during each period .DELTA.T the axis position at which the member should reside; and the latter number is used with a dynamically signaled actual position number to re-compute and signal during each period the position error.

Abstract: A machine tool control system moves a grinding wheel from a retracted position to a forward position by causing hydraulic fluid to be applied under pressure to a hydraulic cylinder to effect rapid forward movement of the grinding wheel to a forward position whereupon further movement of the grinding wheel to a final position is effected by supplying a predetermined number of pulses to a stepping motor for driving the feed screw in accordance with a predetermined sequence of grinding movements. Upon completion of the grinding operation, the grinding wheel is reset to the initial retracted position by applying hydraulic fluid to another portion of a cylinder to rapidly move the grinding wheel from the forward position to the retracted position while at the same time applying the same predetermined number of pulses to the stepping motor so as to reversely rotate the feed screw to return the grinding wheel to the initial position.

Abstract: A milling or grinding machine for shaping a workpiece is disclosed wherein a shaping tool is displaced relative to a rotatable workpiece in accordance with coded displacement values of a series of signals stored on a perforated tape. The signals are extracted from the tape serially and are translated into command signals, which are applied to a stepping motor for imparting displacement to means supporting the shaping tool. The stored signals are extracted from the tape in response to output pulses derived from a frequency divider network, the input of which is connected to a pulse generator. The pulse generator is so coupled to means for rotating the workpiece as to provide a plurality of pulses for each predetermined angular displacement of the workpiece.

Abstract: A manual control system including a powered feed for a numerically controlled machine tool. The system includes a manually operable differential resolver located in the position feedback loop of the servo control system for each slide and a variable speed motor for driving that differential resolver at a controlled rate so as to effect controlled feeding movement of the slides independent of the numerical control unit.