Abstract: Methods for monitoring windlass rotation are provided to determine the real time rate and length of rode release when anchoring a boat. The rotation can be monitored in real time using directional sound and/or electromagnetic radiation receivers and/or transmitters that can be in a module attached to the windlass. Another windlass module can monitor windlass rotation using micro-electromechanical systems (MEMS) components such as accelerometers, magnetometers, gyroscopes, and/or inertial measurement units (IMU) to sense motion and/or position.

Abstract: An apparatus for measuring wire and cable length is provided for using a wireless encoder for wire and cable processing. The apparatus for measuring wire and cable length may include a housing, battery, communication component, microcontroller, printed circuit board, encoder module, encoder disc, shaft, wire counter and spool.

Abstract: An electrostatic capacitance measuring device includes: a base substrate; a first sensor having a first electrode, one or more second sensors each having a second electrode, and a circuit board mounted on the base substrate. The first sensor is provided along an edge of the base substrate. The second sensors are fixed on the base substrate. The circuit board is connected to the first sensor and the second sensors, and configured to output high frequency signals to the first electrode and the one or more second electrodes and obtain a first measurement value indicating an electrostatic capacitance from a voltage amplitude at the first electrode and one or more second measurement values indicating electrostatic capacitances obtained from voltage amplitudes at the one or more second electrodes. The measuring device has one or more reference surfaces fixed on the measuring device and facing the one or more second electrodes.

Abstract: A system and control method for determining an amount of paper product dispensed from a dispenser or remaining in the dispenser is provided. The paper product is initially loaded in the dispenser as a paper product formation, such as a roll or stack of the product. At defined intervals, a digital image of an aspect of the paper product formation in the dispenser is taken and transmitted to a digital imager processor. A feature of the digital image that changes as the paper product formation decreases in size as the paper product is dispensed is analyzed and compared with a predetermined value of the feature at a predefined size of the paper product formation to determine an amount of the paper product dispensed or remaining in the dispenser.

Abstract: A power winch for motor vehicles includes a display panel for displaying the operation status of the power winch and letting users know whether or not the power winch is situated at an electrical connection status for use, the voltage of a vehicle power supply connected to the power winch, whether or not the power winch is connected to the wireless handheld controller normally, and whether a steel wire rope of the power winch is wound or unwound, so as to improve the safety of operation, control, and use. The power winch further includes a storage holder installed on a surface of the power winch for storing the wireless handheld controller to facilitate a quick access or use of the wireless handheld controller, so as to improve the convenience of operation, control and use.

Abstract: A machine tool is provided capable of detecting an abnormality caused by detaching a spindle. The machine tool includes: the spindle configured to rotate a workpiece or a tool; a sensor configured to output a signal according to a rotation angle of the spindle; and a controller configured to detect occurrence of an abnormality in at least one of the spindle and the sensor when an electrical signal different from the signal output during each of rotation of the spindle and halt of the spindle is output from the sensor.

Abstract: A warning circuit for use on ladders includes a first sensor responsive to the placement of a first of a user's feet thereon and a second sensor responsive to the placement of a second of the user's feet thereon. The second sensor is electrically connected in series to the first sensor, and a relay is electrically connected in series to one of the first and second sensors. A power source has a power output terminal electrically connected in series to the other of the sensors connected in series. A sound device is electrically connected to a load output of the relay and to the power source. The load output of the relay is energized only when the first sensor is activated prior to activation of the second sensor whereupon the load output then energizes the sound device.

Abstract: The present embodiments provide a wheel assembly having a dynamic structure to influence an unloaded profile of a tire. In one embodiment the unloaded profile is also influenced by a centrifugal force on the wheel assembly and an inflation pressure of the tire. In one embodiment, a loaded profile of the tire is influenced by a weight of the wheel assembly, the inflation pressure of the tire, and the centrifugal force on the wheel assembly.

Abstract: A system includes a handheld tool for executing steps of a sequence within a work cell. An electromagnetic marker connected to the tool emits a magnetic field within the cell. A receptor detects the magnetic field and generates a raw position signal in response thereto. A control unit updates an assembly setting of the tool. The host executes a control action when a position determined using the raw data is not equal to an expected position in the sequence. A method calculates the present position of a torque wrench using magnetic fields generated by the marker and measured by a receptor array, and calculates a present position of the tool or a fastener. The present position of the fastener may be compared to an expected position in the calibrated sequence, and the torque wrench may be disabled when the fastener position is not equal to the expected position.

Abstract: A pulse signal output unit sends three-phase pulse signals according to movement of the movable member. A counter unit adds a first predetermined value or a second predetermined value to a count value or subtracts the first predetermined value or the second predetermined value from the count value, according to a combination of the pulse signals appearing when all the pulse signals are normal and a combination of the pulse signals appearing when one of the pulse signals malfunctions. A position detection unit detects the position of the movable member according to the count value.

Abstract: An on-foot pedestrian navigation module useful for pedestrian navigation when operated with at least a control unit and another on-foot pedestrian navigation module, comprising (a) at least a first sensor unit and a second sensor unit, wherein each sensor unit including an up/down sensor adapted for sensing an ‘up’ condition and a ‘down’ condition associated with relative displacement of the module with respect to a surface, and a signal transmitter/receiver adapted, in response to an activation signal coming from a module controller, for generating a propagating signal (b) a module controller for controlling the operation of the module in response to a control signal coming from the control unit and (c) a communication unit for enabling said module to communicate with said at least the control unit and other module, thereby facilitating collecting motion data at the control unit and integrating the motion data with motion data coming from the other module, the motion data being indicative of a condition of e

Abstract: A device for counting printed products of an imbricated stream includes a first measuring unit for detecting a printed product edge directed transversely of the conveying direction of the imbricated stream and with an evaluating unit which receives signals of the first measuring unit for counting the printed products. Therefore, it is the primary object to provide a device of the above-described type which facilitates a higher counting accuracy even in the case of irregular imbricated streams of products.

Abstract: An absolute position sensor with serial reading, that includes at least one detector capable of detecting transitions in a target pattern present on a member mobile relative to the detector. The sensor includes a shift register capable of storing a predetermined number of consecutive data from the detector, and a mechanism comparing the value of the register to a set of predetermined values each corresponding to a position of the detector relative to the target pattern.

Abstract: An encoding system includes an absolute encoder, a converter, a storage system, and a processor. The converter is connected between the absolute encoder and the storage system to determine amplitudes of two encoding waveforms from the absolute encoder when a motor rotates. The storage system determines an angle through which the motor rotates between a first time and a second time, according to the amplitudes of the two encoding waveforms.

Abstract: The invention relates to a registration system for sheet fed processing machines that reduces or eliminates the need to calibrate the register and/or timing dials of such a machine. The system uses known measurements and the elapsed time between electrically generated pulses to determine the relative position of processing cylinders in the machine relative the timing of a feed mechanism. The relative positions are displayed in real-time and can be adjusted by an operator. The machine need not be ‘in time’ to properly register the machine.

Abstract: An inkjet printer correction device and method. A correction device having a first circuit generating a first processing signal composed of a first and second pulse signal according to a first and second phase signal produced by an encoder, a second circuit generating a second processing signal based on the position change variation of either the first or second phase signal, a third circuit generating a third processing signal based on the position change variation of either the first or second phase signal, a selector selecting one of the first, second, or third circuits according to the first processing signal. The present invention provides one of the first, second, or third processing signals to control the speed and position of motor of the inkjet printer.

Abstract: A sensor device which detects a positional relationship between an first member and second member, includes a signal source generating an electrical signal, a first electrode receiving the electrical signal and storing an electrical charge at a first part on the first member, a second electrode inducing an electrical charge at the second part on the second member, a third electrode inducing an electrical charge at the third part on the second member, a fourth electrode inducing an electrical charge at the fourth part on the first member, a reference electrode disposed at a fifth part on the second member to be connected to a reference voltage point, a fifth electrode inducing an electrical charge at the sixth part on the first member, and a differential amplifier amplifying a voltage difference between the fourth electrode and the fifth electrode and outputting a difference signal.

Abstract: A method using a printing system comprising a controller programmed for rendering imposed documents given media cost considerations is described. The method includes steps of: evaluating a print job; evaluate media loaded within printer; and determining media print options including cost. Additionally, embodiments enable user selection of printing option prior to the printing system or rendering the print job or selecting a printing option based on user profile. The print job is then rendered.

Abstract: A sensor device for detecting a positional relationship between a first member and a second member, includes a first charge-holding electrode provided on a surface of the first member and holding a charge, a second charge-holding electrode provided on the surface of the first member and holding a charge differing from the charge held by the first charge-holding electrode, a first charge-induced electrode provided on a surface of the second member, the first charge-induced electrode having a charge induced therein in accordance with the charge held by the first charge-holding electrode, when the first charge-holding electrode approaches the first charge-induced electrode, a second charge-induced electrode provided on the surface of the second member, the second charge-induced electrode having a charge induced therein in accordance with the charge held by the second charge-holding electrode, when the second charge-holding electrode approaches the second charge-induced electrode.

Abstract: The invention relates to a timing disc fitting for an encoder system. It consists of a timing disc hub (1) which can be plugged to a motor shaft (2) and to which there is fixed a timing disc (3). In accordance with the invention, the timing disc hub consists of a metallic heat-conducting material to which, on one side, a plastic insulating material is adhered. In the flange plane (1a) of the timing disc hub (1) there are arranged projections or lugs (5, 6, 7) which engage correspondingly shaped indentations, recesses or cut-outs (3a, 3b) in the timing disc (3).

Abstract: A rotation angle detector for detecting the angular position of a shaft, i.e. a camshaft or a camshaft of an internal combustion engine, includes a rotatable detector wheel coupled to the shaft. Markings of a first type are distributed along a periphery of the detector wheel and are detectable by a sensor for determining a relative rational angle. Markings of a second type are also distributed over the periphery of the detector wheel. The markings of the second type are distinguishable from each other for determining an absolute rotational angle of the shaft or for determining selection of a combustion chamber for injection.

Abstract: LED Christmas tree for drag racing starting and timing having light emitting diode signal lights arranged on an upper display tier and on a lower display tier.

Abstract: An error detection method for use with a two channel increment encoder. The error detection method operates to detect errors over a wide range of rotational velocity of a rotating member. The error detection method employs the signal from one or two of the channels of the encoder and determines if pulse edges from the signals deviate from expected normal behavior. When an error is detected, actions can then be taken by the controller for the rotating member to prevent undesired results.

Abstract: Apparatus and method for testing an optical encoder used to determine position of a moveable member. The optical encoder supplies a first binary signal indicative of a position of the moveable member and a second binary signal indicative of the position. The first binary signal and the second binary signal are in quadrature relationship. The apparatus has a first delay device connected to receive the first binary signal. The first delay device produces a first delayed binary signal. The apparatus also includes a first logic gate connected to receive the first binary signal and the first delayed binary signal. The first logic gate produces a first edge detection pulse signal. The apparatus further includes a second delay device connected to receive the second binary signal. The second delay device produces a second delayed binary signal. The apparatus further includes a second logic gate connected to receive the second binary signal and the second delayed binary signal.

Abstract: A device for controlling a multi-cylinder internal combustion engine with a rotatable shaft has a transmitter wheel mountable on the rotatable shaft and having a number of uniform spaced angular marks spaced and at least one reference mark which as a synchronization mark for forming control pulses for the internal combustion engine, a sensor which senses the transmission wheel and supplies a rectangular output signal corresponding to its surface, a computing device which evaluates the output signal and compares time intervals of uniform signal flanks with one another or sets them relative to one another in a certain ratio, to recognize the reference mark, and after a first recognition of the reference mark occurrence of the reference mark by counting of the uniform signal flanks is recognized and in addition the distance of the signal flanks is tested and thereby the recognized reference mark is tested for plausibility, an error counter arranged so that when a non plausibility is recognized it is incremented

Abstract: An apparatus and method for detecting the absolute position of a movable member, by monitoring the incremental and directional of movement of an indexed-encoder, coupled to the movable member, and comprising a single index space and a plurality of non-index spaces. The index space of the indexed-encoder member has a characteristic different than a characteristic of all of the other non-index spaces. The apparatus is capable of distinguishing the index space from any of the non-index spaces based on the characteristics of the index space and non-index spaces, and thus detecting when the index space or any of the non-index spaces is at the predetermined location.

Abstract: The device for electronically simulating a component position includes a first counter (40,42) which counts counter pulses (Zt) determined by respective occurrences of a periodic event marking respective component positions; a second counter (30) which, in response to occurrence of a first event (e2), starts a third counter (34) which counts at a counting rate faster than that of the second counter (30) so as to repeatedly run through a predetermined value range (Z') until occurrence of a subsequent event (e3) and which produces a basic clock pulse (Co) each time a final value (y) of the predetermined value range (Z') is reached; and a readjustment circuit (38) which produces the counter pulses (Zt) from the basic clock pulses (Co).

Abstract: A counting apparatus including a sensor surface having a plurality of zone locations with pressure actuated switches which produce a contact event signal corresponding to the zone location when an object traveling across the sensor surface contacts the zone location, a microprocessor connected to the pressure actuated switches having software for analyzing the contact event signals according to predetermined temporal and spatial criteria stored in the memory of the microprocessor, the microprocessor producing an increment signal when a sequence of contact event signals satisfies one set of criteria related to "in" counts and a second increment signal when a sequence satisfies another set of criteria related to "out" counts, and a counter with a two-channel count register which increments one channel in response to an "in" increment signal and increments a second channel in response to an "out" increment signal.

Abstract: A safety-related control system (SRCS) designed to safeguard personnel operating hazardous production equipment. The SRCS integrates the safety-related part of a machine into one homogenous system for the purpose of increasing safety. In so doing, the SRCS monitors the machine, the operator, and itself for safe operation. The SRCS utilizes a non-material barrier to sense the intrusion of a person's body into a hazardous area of a machine. The SRCS uses machine feedback and/or operator interface to determine whether a hazardous condition is present. If such condition is present, the hazard is rendered harmless by the time the intruding body member can reach the potential danger area. The system includes separable means for stopping motion of the moving parts of the equipment, starting movement of the movable parts, and detecting faults in sections of the system.

Abstract: The present invention relates to a control means for a printing machine, in particular a sheet-fed offset printing machine, having a plurality of units, such as feeders, printing units, varnishing and coating devices, deliverers, folding apparatus and the like, each unit being assigned a station having at least one computer and these stations being connected to one another via a first bus. It is intended to ensure that the switching processes which are to be carried out in the individual units of the printing machine at specific, predetermined angle positions can proceed exactly, even at the highest machine speeds. According to the present invention, for this purpose it is proposed that, in addition to the first bus, via which the stations exchange signals with one another, a second bus is provided, via which the individual stations may be fed with the angle position signals of a single-turn rotating angle encoder which is fitted on one unit of the printing machine.

Abstract: A synchronized voltage controlled oscillator lap counting circuit includes a bearing resolver circuit having a single Hall-effect sensor element which provides differential voltage output signals in response to an external magnetic field. The differential amplifier receives the differential voltage output signals and provides a single amplified output signal. The single amplified output signal is provided to a voltage controlled oscillator. A pedometer provides a repetitive pulsed-output signal in accordance with movements of a user. The repetitive pulsed-output signal and a voltage controlled oscillator output signal are provided to a micro-controller. The micro-controller samples the voltage controlled output signal in synchronization with the repetitive pulsed signal output from the pedometer to resolve bearing directions based on intercepted frequencies of the voltage controlled output signal.

Abstract: A method for detecting the position of a linear stepping motor which includes the steps of generating a reference clock signal for detecting the position of the linear stepping motor using an oscillator and counting the reference clock signal with a counter, generating digital values of carrier sine waves sin.omega.t and cos.omega.t by inputting the output of the counter to a ROM having sine and cosine functions, converting the digital values of the carrier sine waves sin.omega.t and cos.omega.t to analog sine wave signals sin.omega.t and cos.omega.t using a digital-to-analog converter and outputting the result, generating the signals sin.omega.tcos.theta. and cos.omega.tsin.theta. by multiplying the analog sine wave signals sin.omega.t and cos.omega.t by sine wave signals sin.theta. and cos.theta. from a linear scale in a multiplier, adding the signals sin.omega.tcos.theta. and cos.omega.tsin.theta. in an adder to form a modulated signal sin(.omega.t+.theta.), converting the a modulated signal sin(.omega.t+.

Abstract: A device which reshapes sinusoidal signals with a singularity to generate square-wave signals and detects the singularity in an unambiguous and reliable manner. The sinusoidal pulses are reshaped into square-wave pulses in such a way that the edges of the square-wave pulses always occur at the same location regardless of the height of the sinusoidal signal. This is achieved in that a change in the edges of the square-wave signals is initiated whenever the sinusoidal signal crosses the zero-axis. The required signal processing and logical comparisons, which also enable a definite detection of reference marks, are carried out in a suitable circuit arrangement.

Abstract: A system and method for testing an electronic circuit is disclosed. The system includes a circuit board test platform having multiple electronic test capabilities and multiple hardware resources, and a pay-per-use module that is coupled to the circuit board test platform. The pay-per-use module is adapted for monitoring use of the multiple electronic test capabilities and the hardware resources of the circuit board test platform, and for debiting a number of usage credits from a usage credit pool based on the use of the multiple electronic test capabilities and the tester hardware resources.

Abstract: Rotation of a code plate fixed to a shaft of a detecting object is detected for producing a one-rotation signal and an incremental signal corresponding to a division of one revolution into a plurality of equal sections. The incremental signal is counted by a counter, thereby detecting an absolute position using an encoder. The counter is cleared in response to a one-rotation signal arriving first after the encoder starts its detecting operation. The counter continues to count the incremental signal in proportion to rotation of the shaft of the detecting object after its count value is once cleared, without clearing the count value in response to subsequent one-rotation signals. Thus, the counter obtains an absolute distance from a position where the counter received the first one-rotation signal to a present position.

Abstract: A spline counting mechanism for determining the number of splines on a shaft. The spline counting mechanism includes a plunger urged into engagement with the shaft and adapted to be rotated with respect to the shaft. The plunger is adapted to engage each spline on the shaft as the plunger is rotated through one revolution and is operable to establish and cut off electrical continuity in an electrical circuit as the plunger rotates into engagement with and then beyond each spline. The mechanism further includes a digital counter for counting and displaying the number of times that electrical continuity is established in the electrical circuit, this number being equal to the number of splines on the shaft.

Abstract: A register control system, particularly one that registers marks on a printed web to a function cylinder, produces proportional and integral gains each independently variable to control the take over point of the integral gain with respect to the proportional gain. The accumulating integral gain is zeroed out after cross over if the proportional gain exceeds a preset percentage of the integral error band. The overall system gain is varied with the line speed independently of the proportional and integral gains to provide speed-insensitive control. The direction of automatic correction is always selected to return the system to register in the shortest distance possible. High frequency clock pulses are counted between encoder pulses to interpolate with high accuracy the angular position measurement of the marks and a homing pulse.

Abstract: The analyzer circuit includes a first oscillator producing an output signal having a first frequency depending on an inductance of an inductive position sensor having two oscillator coils positioned near a movable part; a switching device in the first oscillator for alternatingly connecting one of the two coils and simultaneously disconnecting the other according to a state of the switching device; a frequency divider for converting the output signal at the first frequency to another output signal at another frequency; a counter for counting a pulse signal under control of the other output signal of the frequency divider; a second oscillator connected to the counter and providing input pulses at a fixed frequency to the counter, which counts the input pulses under control of the other output signal of the frequency divider; a start synchronizing circuit for starting and synchronizing the divider and the counter; a flip-flop connected to the frequency divider and to the switching device to switch the state of

Abstract: A currency counter for counting currency notes withdrawn from a supply and advancing the notes one by one along a path past a density detector and a magnetic material detector to a stacker at a delivery location upon energization of a common drive motor in which an amplifier responsive to the density detector is automatically calibrated each time the counter starts and in which density and motor current signals are combined for doubles detection. The motor speed is adjusted for document length to provide a predetermined number of counts per minute. An adaptive counterfeit check is made. The motor is deenergized at the end of a batch count and momentarily reenergized to ensure that the last note of the batch is stacked.

Abstract: A position detecting apparatus comprises a motion detecting section for generating a pulse when a carriage passes each of coordinate points set in a reciprocal movement span thereof at a predetermined pitch, and a counting section for storing position data representing an initial position of the carriage in advance, incrementing the position data in response to a pulse which is generated by the motion detecting section when the carriage is moved in the forward direction, and decrementing the position data in response to a pulse which is generated by the motion detecting section when the carriage is moved in the backward direction.

Abstract: A revolution counting circuit for performing such an operation includes a pulse multiplying unit for multiplying signal pulses generated by an encoder and a pulse dividing unit for dividing the multiplied signal pulses by a divided value set up by a microprocessor. Further, a revolution counting circuit may include a pulse selection unit for selecting one of the signal pulses generated by the pulse multiplying unit and the pulse dividing unit. Also included are a waveform shaping unit for generating a pair of divided signal pulses having the same phase difference as the signal pulses generated by the encoder and a control signal generator for sending control signals to the waveform shaping unit.

Abstract: A programmable, electronic, angular position indicator, based upon engineering units, estimates the angular displacement of a rotating rotor. The angular position indicator is programmed with the particular arrangement of teeth (or other markings) on the rotor. Intermediate angular displacements are interpolated between a limited number of positive angular displacement indications. Offsets, due to acceleration or deceleration of the rotor, are corrected at each positive angular displacement indication without skipping the output of each interpolated angular displacement. Angular displacement is determined in standard engineering units.

Abstract: A precision, high-resolution, absolute, multi-revolution encoder which allows a multi-revolution position value of a shaft to be detected with high reliability, using only a single revolution detector, and makes multi-revolution detection indirectly related to the accuracy of a rotary angle position signal. The output signal from the single multi-revolution detector is used, together with an inverted output signal, to increment and decrement corresponding up/down counters, based on the direction of rotation of the shaft. Each of the up/down counters is incremented or decremented at different points or zones of the shaft rotation so that the rotational value can be determined unambiguously. A conventional grey-code detector provides accurate angle values. The counters may exist as discrete hardware or integrated software embodiments.

Abstract: There is disclosed a position detection method of a robot which provides two incremental position transducers mounted to a robot axis in interlocked relationship with each other and rotatably to produce pulse signals having the number different from each other in response to a moving distance of the moving robot axis and detects a difference between the numbers of pulses produced from the position transducers to detect the position of the robot. Further, a difference (P.sub.2i) of the pulse number between reference pulses produced from the two position transducers at any position of the moving robot axis is calculated and the pulse number (i) of a next reference pulse from a reference position is then calculated on the basis of i=(P.sub.1 -P.sub.2i)/(P.sub.1 -P.sub.2) where P.sub.1 and P.sub.2 are the numbers of pulses produced during one rotation of the position transducers, respectively, so that P.sub.1 .times.i is calculated to detect a position of the robot axis.

Abstract: A novel position sensing device and novel method for determining position use an electronic memory to retain a look up table for calibrated position indicia on a scale. The position indicia are preferably arranged along the scale so that at least two indicia are positioned at unique distances apart in each length segment of the scale. A reader electrically reads the at least two indicia of a segment and the electronic memory look up table allows the at least two indicia to determine the segment, position within segment, and the position relationship between the position within the segment and the reader. Preferably, the indicia are slits in a scale bar, and the reader is a light source and charge-coupled device. The position of the slits is preferably determined using more than one pixel of the charge-coupled device.

Abstract: The present invention relates to a counter circuit for counting the rotated position of the motor and controlling absolute position of the same to control an absolute position of a robot system, which comprises, a RS-422 receiver for receiving encode signals from a motor driver, a 16-bit counter device for receiving rotated-number data of the motor supplied from the receiver and counting the data to output the counted value to a CPU via a bus line, a plurality of 4-bit counters for counting the signals when overflow or underflow is produced at the 16-bit counter portion, a first 8-bit latch circuit for receiving the counted values from the 4-bit counters and outputting the counted values to the CPU, and, a second 8-bit latch circuit for controlling the output state of the receiver on the basis of a control signal supplied through the bus line when a zero pulse control signal is inputted for searching an origin of the robot system thereby preventing erroneous counting operations due to a program and reducing t

Abstract: A rotational position detecting apparatus detects the rotational position of a rotating object and compensates for an eccentricity of the rotating object. First and second sensors generate first and second detection signals having phases offset relative to each other. An error signal denoting the eccentricity of the rotating object is generated in accordance with a fluctuation of an amplitude signal corresponding to a difference between amplitudes of the first and second detection signals. The error signal is added to a position signal to obtain a eccentricity compensated rotational position detection signal.

Abstract: An absolute position detecting device in which the number of revolutions of a drive shaft adapted to drive an object to be controlled is counted with a counter for detecting an absolute position of the object. When a predetermined point on the object returns to an initial position after making one or more revolutions, the drive shaft is returned to an initial rotational angular position. A data rewriting operation is performed to rewrite, as necessary, the count value of the counter into a value obtained by subtracting a count value therefrom which is obtained during the one or more revolutions of the predetermined point.

Abstract: A linear scale measuring device of the absolute type capable of exhibiting high resolution and accomplishing the measuring operation with high accuracy. In the device, A cycle of indented lines for increment data is set to be twice as large as that of indented lines for absolute data. Also provided is an absolute data detection section which detects absolute data values corresponding to the indented lines, and a data converter which converts an output of the absolute data detection section into a digital signal. An operation section which includes a computing element adds either +1 to -1 to the digital signal output from the data converter, or does not add to the digital signal, in accordance with an output signal from an interpolation section.

Abstract: The present invention (50) corrects duty-cycle errors generated by imperfections in encoder scales and encoder detectors. A preferred embodiment of the invention operates by detecting successive transparent-to-opaque transitions of the encoder scale (20), calculating the distance between the transitions, dividing that distance by two, and generating a synthetic encoder pluse that is timed to represent a position 50 percent of the distance between the transparent-to-opaque transitions.