A plug gauge includes a housing, defining an internal volume, first openings, and second openings. The plug gauge includes first contact elements, each at least partially received in a respective one of the first openings. The plug gauge includes a first plunger in the internal volume and movable relative to the housing. The first plunger is biased to urge the first contact elements radially outward through the first openings. The plug gauge includes a first sensor sensing movement of the first plunger. The plug gauge includes second contact elements, each at least partially received in a respective one of the second openings. The plug gauge includes a second plunger in the internal volume and movable relative to the housing. The second plunger is biased to urge the second contact elements radially outward through the second openings. The plug gauge includes a second sensor sensing movement of the second plunger.

A scale attachment device configured to attach a tape scale for a linear encoder includes a fixing block and housing members. The fixing block fixes the central part of the tape scale in the lengthwise direction by pressing the central part onto a target object. The housing members include a groove to house a remaining part of the scale on both sides of the fixing block. The tape scale is inserted into the groove in the lengthwise direction with its back surface facing the bottom surface of the groove of the housing member, and thus housed in the groove. The width dimension of the opening of the groove is smaller than the width dimension of the scale.

The linear conveyor device includes a position detecting device including a scale attached to a slider, and a sensor structural body including a sensor and a driver. The driver is provided with a first and a second signal processing units, and a signal comparison processing unit. The first signal processing unit performs predetermined first interpolation processing on an output signal from a first sensor, generates and outputs first positional data. The second signal processing unit performs predetermined second interpolation processing on an output signal from a second sensor, generates second positional data, and outputs the second positional data. The signal comparison processing unit recognizes the first positional data as positional information of the slider, generates identification information unique to the slider, and outputs the identification information, where the identification information corresponds to a difference between the first positional data and the second positional data.

There is provided a motor driving system in which an encoder sensor is configured to move with a driven object with respect to an encoder scale and output an encoder signal. A controller is configured to control a motor based on the encoder signal, thereby controlling movement of the driven object. The controller estimates an obstructing area. In the obstructing area, the encoder sensor reads a part of the encoder scale where an obstacle is adhered. The controller calculates a control error of the motor in the obstructing area based on the encoder signal output after the encoder sensor passes through the obstructing area, and determines a compensation amount of a controlling input value input during a period while the encoder sensor passes through the obstructing area.

An optical sensor for a delivery device having a piston that displaces a substance, such as a fluid, from a reservoir. The optical sensor has a light source and a detector array for imaging encoding features disposed along a plunger rod coupled to the piston. By virtue of the pattern of encoding features, an absolute position of the plunger rod relative to a fiducial position may be determined uniquely. Thus, the volume of fluid remaining in the reservoir, the rate of fluid delivery, and proper loading of the reservoir may be accurately ascertained. Additionally, the encoding may serve to uniquely identify a version of the reservoir which may be supplied in various versions corresponding, for example, to differing concentrations of a therapeutic agent to be dispensed.

A measurement apparatus includes: a light source that emits light; a scale that has a plurality of tracks whose patterns are different from each other, the tracks passing at least a part of lights emitted by the light source; a light receiving part that has a plurality of light receiving elements that each output an optical signal corresponding to strength of light received through the tracks; and a signal generation part that generates a serial signal in which a plurality of the optical signals are time-division multiplexed and sends the generated serial signal.

A position encoder includes a carrier adapted to move with respect to a first sensor and a second sensor of a position encoder. The carrier also includes encoding elements situated on the carrier to interact with the first sensor. A first limit indicator is situated at a first location on the carrier to interact with the second sensor at a first position of the carrier corresponding to a first limit of the position encoder, and a second limit indicator is situated at a second location on the carrier to interact with the second sensor at a second position of the carrier corresponding to a second limit of the position encoder.

A position-measuring device includes a carrier body and scanning units movable relative thereto. At least three surfaces of the carrier body each carry a first and second measuring graduation, each having a series of graduation lines. Each of the measuring graduations is associated with a scanning unit for scanning the respective measuring graduation at a scanning location such that, for each surface, two scanning units are disposed for scanning the respective measuring graduations. In each case, these two scanning units are disposed in such a way, and the graduation lines of the two measuring graduations are inclined with respect to each other in such a way, that two normal planes extending respectively in the direction of the respective graduation lines through the respective scanning locations of the two scanning units have a common axis of intersection, whereby the three resulting axes of intersection extend through a common point.

A digital displacement sensor and a displacement measuring method thereof, pertaining to the technical field of displacement sensors. The digital displacement sensor includes a housing and a circuit board, and the circuit board is arranged inside the housing. The housing is provided with a window and an opening. The circuit board is provided with a signal acquisition module, an analog front end circuit, a digital compensation circuit, and a signal output interface. The digital displacement sensor allows to alternatively fix the sensor or measured object according to the structure. The measurement can be performed as long as a relative movement between the sensor and the measured object occurs. Factors such as material of the measured object etc. are not limited, so materials such as steel belts, aluminum plates, plastics etc. can be flexibly used. Merely surfaces of the measured object need to be coated with corresponding stripes.

By configuring an encoder scale as an angled or inclined magnet or pair of oppositely arranged, adjacent magnets, a magnetic field sensor in a travel path of the scale can detect an absolute position of the scale for use in an industrial control system. Due to the angle or incline, when a first side of the scale is proximal to the sensor, the sensor can detect an angle of 180. As the scale moves to center with respect to the sensor, the sensor can detect an increasing angle to 0. Then, as a second side of the scale becomes proximal to the sensor, the sensor can detect an increasing angle to +180. The angle changes linearly with position. In one aspect, the pair of oppositely arranged magnets can be rotated with respect to the travel path to provide the angle. In another aspect, the pair of oppositely arranged magnets can be magnetized diagonally to provide the angle.