Abstract: A nominally cylindrical surface of a workpiece is sensed by a stylus displaceable radially of an axis of rotation of the surface relative to a support column defining a reference datum so that the stylus follows the cylindrical surface at a given height along the surface. Relative rotation of the workpiece and the stylus about the axis of rotation of the surface is effected and the displacement of the stylus used to determine information relating to the radial form of the surface at that height. These measurements are represented at different heights along the surface so as to determine its cylindrical form. The displacement of the stylus from a given position on the surface at each height before and after rotation of the stylus and workpiece through 180° are measured and the resulting measurements used to compensate for any error or deviation in the reference datum.

Abstract: A micro-geometry measuring device capable of reducing measuring force thereof for avoiding damage on micro-geometry of workpiece surface and measuring at a high-speed is provided. The micro-geometry measuring device has a stylus mechanism having a stylus mechanism provided to an arm and having a stylus body, a measuring force adjusting mechanism for adjusting a measuring force working between the stylus body and the workpiece, a displacement sensor for detecting a position of the arm, and a measuring force controller for controlling the measuring force adjusting mechanism. The stylus mechanism includes a vibrator for resonantly vibrating the stylus body, and a detector for detecting vibration status changing when the stylus body touches the workpiece. The change in vibration of the stylus body vibrated by the vibrator is directly detected by the detector and a signal therefrom is fed back to the measuring force controller to keep constant measuring force working between the stylus body and the workpiece.

Abstract: A method and apparatus for data disks adapted to compensate for effects of shock loads imparted to a disk drive which are of sufficient magnitude to cause disk shifts. A series of topographical features are formed on the disk surface or edge to cause signal fluctuation in a sensor during read-back mode operation. An initial signal profile is stored as a map indicative of track or disk alignment with respect to the actuator assembly. Selectively, such as after a known shock event, the topographical features are re-profiled. A comparison of the profiles provides a measure of any track distortion which must be compensated for in future read-write operations by adjustments to data track servo follower algorithms.

Abstract: A surface-tracking measuring machine is provided, in which measurement range is enlarged while keeping a measuring force, responsivity, resolution thereof. For the object, the surface-tracking measuring machine has a frame (10), a probe (11) swingably supported by the frame (10) and having a tracer (15) at an end thereof, a measuring force controller (21) for controlling the measuring force applied to the probe, a displacement detector (31) for detecting a displacement of the probe, a measuring force detector (41) for detecting the measuring force applied to the probe, and a controller (51) for comparing a measuring force detected value detected by the measuring force detector and a previously commanded measuring force command value and to control the measuring force controller so that the measuring force detected value is equal to the measuring force command value.

Abstract: A measuring apparatus (1) is provided which has two arms (8) connected to a protection casing (6) through fulcrums (9). Associated with the arms (8), externally of the casing (6), are feeler pins (10) adapted to come into contact with the workpieces (3) and, internally of the casing (6), sensors (11) for measuring the oscillations of the arms (8). Also provided are driving members adapted to exert at least one contact force and one release force tending to rotate the arms (8) in opposite directions and comprising at least one magnet (13) adjacent to the arms (8), magnetic locators (14) integral with the arms (8) and having active faces (14a) turned towards the magnet (13), and drive elements (15) adapted to selectively vary the magnet (13) polarities turned towards the magnetic locators (14).

Abstract: A control system is provided for a pivotally actuated tracer which traces an object (e.g., a frame mount of an eyeglass frame, a lens, or a lens pattern) while the object is held in a more-vertical-than-horizontal orientation. The control system comprises a trace control element and a gravity compensation element. The trace control element applies control signals to the pivotally actuated tracer. In response, the object engager of the tracer is pivotally actuated against and along the object to be traced with a biasing force toward the object. The gravity compensation element is adapted to compensate for the effects of gravity on the object engager by causing a varying pivoting force to be exerted on the object engager. The pivoting force varies depending on the rotational orientation of the object engager to keep the biasing force substantially constant along the object. Also provided is a data acquisition system for the tracer.

Abstract: The present invention comprises an arrangement for the remote sensing and recordation of information about a body component. The arrangement includes a stylus held within a support head. The support head has an electrode therein for the detection and recordation of stylus contact with a body component. A plurality of parallelogram linkages articulably support the stylus. The linkages have a first or input end and a second or output end. A motion tracking generator is attached to the output end of linkages. A sensor is arranged to receive and record signals from the tracking generator in a plurality of orthogonal planes, so as to permit the generation and recordation of contours, location and domain of the body component being sensed by the stylus.

Abstract: A thin board holding device 2A for holding a thin board in a plane state to measure the thickness of a thin board is disclosed, which has a number of spot supports 3 with adsorbing portion for holding a thin board 1 attached by suction to the top. The thin board 1 is held in a multiple point support fashion to the spot supports 3. By moving a measuring terminal of a measuring instrument to a measuring point on the thin board, which has one surface of the thin board 1 set on the thin board holding device 2A, the level of the other surface of the thin board 1 from a reference surface A supporting the thin board holding device at a reference position is measured. The dimension from the reference position A to a thin board adsorption surface 3a of the spot support 3 is used as a computational constant, and the thickness of the thin board is calculated from the measured level of the other surface of the thin board 1 and the computational constant.

Abstract: An airfoil blade measuring apparatus includes an airfoil blade engagement system and a measuring system. The airfoil blade engagement system rotates the mounted airfoil blade to a position to be measured, and elevates the airfoil blade to permit the entire airfoil blade to be easily measured. The measuring system includes a blade engagement tool which positions the airfoil blade, a limit switch, two alignment slides, and a measuring slide including a plurality of laser displacement sensors, which are positioned via a computer controlled motor.

Abstract: A surface-following type measuring machine is provided, which is capable of setting the measuring force to a proper value in an efficient and accurate manner without imposing a burden on the operator in exchanging at least one of the stylus and stylus holder according to the surface contour of an object to be measured. A main body is disposed for movement relative to an object to be measured. A measuring arm is supported by the main body for displacement relative thereto, and carries at one end thereof a stylus holder and a stylus in a manner permitting replacement of the stylus holder and the stylus. Displacement of the measuring arm is detected by a displacement detecting device. The measuring force acting upon the measuring arm is adjusted by a measuring force adjusting device. A memory stores a measuring force command value table having a plurality of command values of the measuring force corresponding respectively to combinations of plural kinds of the stylus holder and plural kinds of the stylus.

Abstract: A surface property measuring device comprises a detector having a stylus for measuring surface property and a skid at a leading end thereof, and a driving mechanism for causing the detector to advance and retreat along a surface to be measured. The measuring device further comprises a detector-lifting plate having an engaging portion engaging with a protrusion of a connector housing when the detector retreats to the utmost. The detecting-lifting plate is fixed to a frame of the driving mechanism, for lifting the leading end of the detector to thereby separate the skid and the stylus from the surface to be measured when the detector retreats. This enables the surface to be measured, a nose, the stylus, and the skid which protrude from the detector, to be protected when arranging the measurement and also removing the measuring device after the measurement.

Abstract: There is provided a reference gage that has first and second reference planes parallel to one another and perpendicular to a rotational axis of the reference gage, and a distance between the reference planes is already known as a reference distance. To calibrate the measuring head, the measuring direction of the measuring head is set parallel to the rotational axis of the measuring head or the table on which the reference gage is placed, and a reference value of the reference distance on the reference gage is entered. Then, the reference distance is measured by the measuring head to acquire measured data, and a measured value of the reference distance is calculated from the measured data. The measuring head is calibrated so that the measured value accords with the reference value. The time required for calibrating the measuring head is thus reduced.

Abstract: A method for determining a torsional structure in the surface roughness of a finished shaft journal includes making a plurality of axial scores on a circumferential strip of the shaft journal, with a high axial measurement point density at different but exactly known circumferential positions as well as with exactly known axial positions. The individual local roughness profiles are printed out in a close sequence with respect to one another corresponding to their positions. The measurement charts are raised or elongated in the radial and axial directions and upset in the circumferential direction. Thus, a topography with multidimensional affinity showing the microstructure of the surface in three dimensions in a diagonal view is obtained. An autocorrelation function is formed from this topography, stochastic elements are eliminated, and a surface topography is obtained that essentially contains only the periodic elements.

Abstract: Method and device for accurately measuring a longitudinal contour of a measuring object, wherein use is made of clamping members for retaining a measuring object to be measured; a scanning arm which is pivotable about an axis transverse to a longitudinal center line of the clamped measuring object and whose free end comprises one scanning needle, the scanning arm being mounted on a driving device which, in operation, can move the scanning arm in one linear direction of movement parallel to the longitudinal center line of the measuring object, and means being provided for detecting the angular displacement of the scanning arm and the position of the scanning arm in said one linear direction of movement; and a processor for processing information regarding the angular displacement and the position of the scanning arm, wherein a contour measurement is made in such a manner that the scanning needle moves along a contour flank in downward direction only, i.e. in the direction of the bottom of a profile groove.

Abstract: The present invention comprises an arrangement for the remote sensing and recordation of information about a body component. The arrangement includes a stylus held within a support head. The support head has an electrode therein for the detection and recordation of stylus contact with a body component. A plurality of parallelogram linkages articulably support the stylus. The linkages have a first or input end and a second or output end. A motion tracking generator is attached to the output end of linkages. A sensor is arranged to receive and record signals from the tracking generator in a plurality of orthogonal planes, so as to permit the generation and recordation of contours, location and domain of the body component being sensed by the stylus.

Abstract: Methods of making an inspection fixture to assess the accuracy of a manufactured, bent tube or tube assembly are disclosed. Coordinates of end points, intersection points, and other points of interest of the bent tubular part are provided to a CAD system. The coordinates are connected by a centerline. The centerline is projected onto an X-Y plane and widened. The projected centerline is extruded in the Z direction. The resulting three-dimensional extrusion is unfolded to form a flat pattern for a tube run. The process is repeated until flat patterns for the parts of a tube fixture are created. The resulting flat patterns are provided to a computer-controlled laser cutting machine. The inspection fixture parts are cut by the laser cutting machine and bent to their final shape in accordance with bend angle information generated from the three-dimensional extrusion in the CAD system. The bent parts are assembled on a base plate and welded together to form the inspection fixture.

Abstract: Back-to back hydraulically linked pistons are mechanically coupled to contact probes and measurement sensors. The pistons are hydraulically linked by small diameter flexible conduits which enable the contact probes and the measurement sensors to be mounted and moved independently of each other without affecting the ability of the measurement instrument to simultaneously measure a plurality of points on a selected predefined surface, such as a human tooth. The present invention overcomes the problems associated with the complex mechanical linkages heretofore required in such instruments.

Abstract: A measuring device for the measurement of workpieces has a base frame with a workpiece receiver to receive a workpiece to be measured, and at least one measuring unit for the measurement of the workpiece. In order to utilize the measuring device as flexibly as possible, and permit the measurement of different workpieces in as simple a manner as possible, the measuring unit can be brought into at least two different positions.

Abstract: Back-to back hydraulically linked pistons are mechanically coupled to contact probes and measurement sensors. The pistons are hydraulically linked by small diameter flexible conduits which enable the contact probes and the measurement sensors to be mounted and moved independently of each other without affecting the ability of the measurement instrument to simultaneously measure a plurality of points on a selected predefined surface, such as a human tooth. The present invention overcomes the problems associated with the complex mechanical linkages heretofore required in such instruments.

Abstract: Apparatus for determining the flatness of a generally circular polishing pad through direct measurement of the pad for use in maintaining the flatness of the pad and the flatness of surfaces of articles polished on the polishing pad of a polisher. The apparatus includes a measuring device, a frame mounting the measuring device being capable of measuring a distance between an upper surface of the polishing pad and a reference plane at plural locations along the polishing pad. The apparatus further includes a controller for controlling the measuring device. The controller is configured to indicate whether the flatness of the pad falls outside a predetermined specification.

Abstract: For roughness measurements, a passive roughness probe 118 having a probe tip 119 is exchanged into the measuring probe head of the coordinate measuring apparatus in lieu of the probe pin having a probe ball which is otherwise used to make coordinate measurements. The generation of the measurement points takes place while using the already available measured value transducers 23 in the probe head of the coordinate measuring apparatus. The desired surface characteristic variables are computed from the stored quasi-analog measured point sequence with the aid of a corresponding software module.

Abstract: A portable metrological instrument for measuring surface finish parameters has a main housing which sits on a workbench. A slidable arm can be extended or retracted over the bench so as to move a stylus over a workpiece. The stylus is fitted to a gauge mounted to the end of the arm. The mounting includes a vertically movable slider which incorporates a mechanism for lifting the stylus away from the workpiece and lowering it back. The operation of the instrument is controlled by modular software which can be reprogrammed using an external device, and the machine is operated by a control panel on the housing or by an identical control panel on a remote controller. The gauge includes an inductive sensor, and the associated circuit includes automatically adjustable error canceling devices. The control system uses the sensed position of the arm to estimate the speed of the motor which drives the arm, avoiding the need for a shaft encoder on the motor.

Abstract: A profilometer has a constant force mechanism for biasing of the stylus arm. The mechanism has a centrally-aligned configuration of the moving magnet relative to the magnetic coil and also has a magnetic shield isolating these elements from other ferromagnetic materials in the assembly. The moving magnet is made of a material that is hard magnetically and the magnetic shield is made of a series of low hysteresis, high permeability materials. The force thus generated by the stylus biasing device is very linear with the drive current upon the magnetic coil at any particular position of the stylus, thereby allowing for control and predictability of the stylus force upon the surface to be profiled. This predictability is used for dynamic stylus force adjustments during profiling of a specimen. The profilometer is also equipped with a balanced, spring-loaded stylus-stabilizing sensor assembly, task-specific dual-view optics for protection of the delicate stylus assembly, and a temperature drift compensator.

Abstract: The invention is a non-contact precision measurement system and a method of measuring using the system. The surface contour of an object is measured,utilizing non-contact components, such as lasers. A measurement unit traverses a linear positioner which is parallel to the object to be measured. Then deviations are measured from a baseline reference to determine any deviations in the positioner. The measurement unit also measures the distance between the positioner and the object to produce a distance profile which is adjusted in accordance with the deviations to determine a true surface profile. This system can also be used to measure both an upper and lower surface profile to determine a thickness or to align a plurality of objects in parallel.

Abstract: An apparatus for measuring a lens frame configuration is provided which comprises an apparatus body provided with a measuring reference surface, a frame holder movably retained by the apparatus body and adapted to hold right and left lens frames of an eyeglass frame so as to rotate and incline a holding plane of the lens frame with respect to the reference surface, a rotating device for rotating and inclining the frame holder, a measuring portion for measuring coordinates of each point in a circumferential direction of a V-shaped groove of the lens frame with respect to the measuring reference surface, and an arithmetic circuit for calculating an inclination of the lens frame in the V-shaped groove with respect to the reference surface from a result obtained by the measuring portion.

Abstract: A rolling digital surface measurement apparatus which measures and records the second elevation differences between a plurality of sequentially oriented, regularly spaced, co-linear points which lie on the surface, and which then computes the elevations of those points relative to a datum line established relative to any two points in the sequence by assuming that the mean curvatures of the tested surface are equal to zero in order to remove the inevitable effects of error compounding.

Abstract: A device 22 for measuring the curvature of an object, such as a tapered shaft 24, includes a support plate 26 and a clamping mechanism 32 for supporting the shaft at one end 34 thereof a holding mechanism 60 retains an opposite end 78 of shaft 24 in a position such that the shaft is in a curved state. The curved state of shaft 24 can be attained by physically moving holding mechanism 60 or by placing a weight 80 on the mechanism. A first transducer 82 includes a slide 88 which is movable along a guide bar 86. A second transducer 98 includes slide 102 which is movable along a guide bar 100. Guide bar 100 is connected to slide 88 for movement therewith. A locator mechanism 114 is mounted on slide 102 for movement therewith and includes a pair of spaced pulleys 144 and 146 biasingly urged against opposite sides of shaft 24 and toward the axis thereof.

Abstract: An apparatus for measuring the shape of a frame of spectacles is provided wherein the shape of a frame is measured with a measuring element which is held in contact with a groove in a rim of the frame while being moved along the groove. To accurately position the measuring element with respect to the groove of the frame before the start of measurement, a positioning device is provided which moves the measuring element horizontally toward the frame, presses the measuring element against the frame with a biasing force, and positions the measuring element at a measurement position. Further, to permit smooth vertical movement of the measuring element and to achieve accurate shape measurement, a thrust device is provided which pushes the lower end face of a measuring element supporting shaft upward at a location displaced from the axis of the shaft.

Abstract: A camshaft checking apparatus, in particular for checking the parameters of the profiles of cams, comprising a support structure and a motor means for positioning and axially rotating the shaft, linear transducers for determining radial dimensions of cams in the course of the rotation, a measuring head for cooperating with a reference portion of the camshaft and locating an angular shaft reference position, a rotary transducer for defining said angular position and angular measuring positions, and a control unit for receiving and processing signals arriving from the linear transducers, measuring head and the rotary transducer.

Abstract: An arithmetic and control circuit 600 calculates an angle .theta. of inclination of one of lens frames 501, 501 of an eyeglass frame 500 from the maximum and minimum of height data Z.sub.n of frame configuration information L (.sub.o .rho..sub.n, .sub.o .theta..sub.n, Z.sub.n) about the lens frame (left lens frame) 501. If the angle .theta. exceeds a given angle .beta., the arithmetic and control circuit 600 adjusts a frame holder 100 holding the eyeglass frame 500 so as to make the angle .theta. smaller than the given angle .beta.. After that, the arithmetic and control circuit 600 again calculates height data Z.sub.n in the direction of a Z-axis relative to radius vector information (.sub.o .rho..sub.n, .sub.o .theta..sub.n) to obtain first true frame configuration information L (.sub.o .rho..sub.n ', .sub.o .theta..sub.n, Z.sub.n) about the lens frame 501 in three dimensional directions. Further, the arithmetic and control circuit 600 calculates a radius vector data difference .DELTA..rho..sub.n (.DELTA..

Abstract: The invention provides an apparatus, and a method, for detecting the tread profile of a tire mounted about an X-axis comprising a non-contact Y detection means movable in parallel to the X-axis for measuring the distance at a right angle between such means and the peripheral surface of the tread profile in the direction of the Y-axis, X detection means for detecting the position of the Y detection means along the direction of the X-axis, data memory means for storing X and Y data pairs obtained by both such detection means, and radius calculating means for calculating the radius of the article from the X and Y data stored in the data memory means.

Abstract: An apparatus (1) for the scanning of a profile, e.g. the cross-sectional profile of a train wheel (2,3), comprises a stationary part (11) which supports a first arm (22) and a second arm (23), the ends of said arms being coupled together by means of angle-encoding joints (20,21). One of the arms (23) comprises a free end with a measuring wheel (24) which is arranged to be moved in contact with the profile which is to be scanned.Both of the Joints (20,21) are electronic angle encoders which are coupled to a portable computer via an interface circuit.

Abstract: In a copy control device wherein a model (6) and a workpiece moved relatively with a tracer head (4) and a tool in an X-Y plane, measured distance values to the surface of the model, which are detected by first and second non-contact detectors (5a, 5b) obliquely mounted on the tracer head (4) rotatable about a Z axis are periodically sampled to obtain the coordinate values of measured points on the surface of the model, a normal vector (Nn) on the surface of the model is calculated from three coordinate values out of four measured points (P1n-1, P1n, P2n-1, P2n) successively obtained by the both detectors, and the tracer head is rotated so as to move along a projection (N1n) of the normal vector (Nn) on the X-Y plane, so that measuring axes of the detectors are controlled to be approximately vertical to the surface of the model.

Abstract: An apparatus and method for measuring the squareness of fabricated plate structures by providing a measuring table having a straight reference gauge extending squarely across the table, and a plunger-operated measuring gauge rigidly mounted on a carriage which is slidably mounted to the underside of the table so as to slide the plunger at right angles to the reference gauge, positioning the plate on the measuring table with a first edge abutting the straight reference gauge, retracting the plunger, moving the carriage which holds the measuring gauge to a position in front of a second edge of the plate, releasing the plunger slowly until it contacts the second edge, activating the measuring gauge, moving the carriage along the length of the second edge and holding the plunger in constant and continuous contact with the second edge to measure deviations from squareness between the first and second edges with the measuring gauge, moving the carriage and gauge with plunger mounted thereon clear of the plate, and

Abstract: The roughness of an area of the surface of a workpiece (W) is measured by bringing a height measuring device (10) to points on the surface and using the device to measure the height of each point relative to a datum level defined by a skid (17) while the device (10) is stationary relative to the surface. The points are arranged in a repetitive pattern in two dimensions across the area. The movement between the points is brought about by orthogonally arranged stepping motors (20,22).

Abstract: A stylus profilometer having a counterbalanced stylus with a motion transducer using a vane moving between parallel, spaced-apart, conductive plates which damp the motion of the vane by means of trapped air. The vane forms an electrode with the plates so that the combination is a pair of capacitors in a balanced bridge arrangement. Motion of the stylus causes an unbalance of the bridge indicative of the extent of stylus motion. A lever arm associated with the stylus has a tip influenced by a magnetic field which biases the stylus or controls force on a surface to be measured. The entire assembly has a very low moment of inertia to reduce the effects of vibration on the stylus and thereby increase resolution of the device and reduce damage to the substrate.

Abstract: A fixture for measuring runout in firearm cartridges, casings and bullets is provided. The fixture holds the cartridge at the tip and forward of the rim for rotation. A self centering tip bearing holds the tip of the cartridge, casing or bullet for rotation about an axis of rotation. The exterior surface of the cartridge, casing or bullet is supported in a V-shaped knife edge bearing. The distance from the knife edge bearing to the tip bearing is adjustable to accommodate various cartridge sizes. Interchangeable tip bearing tools are provided for rotatably holding bullets and casings, and for locating areas of variation in the thickness of the casing wall. The thickness indicating tool has a flat surface offset from the cartridge axis, which rests against the curved interior surface of a casing, forming a chord which supports the interior surface at two points. The gauge arm, placed on the outside of the casing between the two points, can then measure the relative thickness of the casing wall.

Abstract: A three-dimensional displacement measurement apparatus includes a planar displacement measurement portion which measures a displacement of a measurement point on a surface of a measurement object in the direction of an X-Y plane, a vertical displacement measurement portion which measures a displacement of the surface in a vertical direction with respect to the X-Y plane, and a vertical displacement measurement position compensation portion that tracks a displacement of the measurement point on the X-Y plane.

Abstract: A probe for inspecting contoured surfaces by transmitting and receiving eddy currents includes a shaft disposed in spatial relationship with the contoured surface and a pivotal probe manipulator rotatably mounted on the end of the shaft and having a critical dimension including the location of the pivot point and the width of the probe manipulator and spring means urging the probe manipulator against the contoured surface so that the probe travels along the surface and rotates substantially .+-.90 degrees relative to the shaft.

Abstract: A method for reading the shape of any elastically deformable article uses a contact feeler to follow the shape to be read. The contact feeler is applied to the article with a force of particular value adapted to cause localized deformation of the article and the coordinates of the contact feeler are noted at the relevant time. Two successive coordinate readings are systematically carried out, one with a first non-zero set point value of the contact feeler application force and the other with a second non-zero set point value of the application force different than the first set point value. The coordinates for a zero set point value of the contact feeler application force are deduced mathematically from the two coordinate readings.

Abstract: A flexible, modular gage system is presented for statistical process control to compare the delta dimensional difference between a master part with known dimensional values to one or more manufactured production parts. A main feature of the invention is the gage that holds measurement devices, such as a transducer probe. The components of the modular auto gage allow position of analog, digital or mechanical measurement devices in virtually any position, being limited only by the part-holding device or interference with other measurement devices. Measurement devices once positioned can remain stationary or attached to a precision pneumatic slide. The pneumatic slide retracts the measurement device to allow easy loading and unloading of the part to be gaged.

Abstract: The positioning and/or configuration of the fixtures used in the various machines or stations of a production line are checked by an automatic checking device including a coordinate-checking unit which moves automatically along the line and stops at each machine or station in order to carry out the necessary checks. A stationary electronic control unit near each machine or station is connected to electronically-controlled actuator means on the checking unit in order to control the movement of a feeler head of the checking unit according to a predetermined program adapted to the specific station at which the checking unit has stopped.

Abstract: Device comprising a support (21-23) with a seat (27, 27') housing a measuring cell (24, 24') having a feeler (6, 6') adapted to contact the part to be checked and with a strain gauge transducer (12-17) for detecting the feeler position. In order to obtain a device with very small overall dimensions and high accuracy and repeatability, the measuring cell (24, 24') comprises an integral element (1) having a support portion (2) fixed in the seat (27, 27'), a free portion (4, 4') carrying the feeler (6, 6') and an intermediate resiliently deformable portion (3, 3'), whereto there is fixed a strain gauge (13) of the transducer (12-17).

Abstract: A metrological apparatus for measuring form and texture of a surface employs an inductive transducer producing an AC gauge signal, and a tracking AC analogue to digital converter. In order to avoid errors in the output signal at a relatively high speed of traverse of the surface due to a non-flat frequency response of the converter, the output signal is processed by a digital filter to provide a combined frequency response which is flat over a desired range. In order to avoid errors in the output signal due to non-linearity of the transducer, a square or cubic correction is applied to the signal. A method calibrating the apparatus to obtain coefficients for the square and cube terms in the correction process is also described.

Abstract: A scanning head (12) for a surface measuring machine has a probe tip (30), which is supported by a probe tip support lever (18) so that it can be deflected perpendicularly to the reference surface (82). Incorporated between the probe tip (30) and a rigid section of the probe tip support lever (18) is a force sensor (34), whereof the output signal serves as an actual value of a control circuit (56 to 60), which controls a magnetic servo motor (44, 46), which exerts a variable additional force, to be added to the force of a tension spring (42), on the probe tip support lever (18), the whole so that the contact pressure of the probe tip (30) is kept constant irrespective of the surface contour.

Abstract: An eyeglasses frame tracing device used in an eyeglasses lens grinding machine. The eyeglasses frame tracing device of the invention comprises a horizontally movable base portion, a rotary base rotatably supported on the base portion, a shaft including a measuring element at its upper end, the shaft being retained on the rotary base so as to relatively move in the vertical and lateral direction with respect to the rotary base, a light-shielding plate which moves in association with the vertical movement and lateral movement of the measuring element shaft and which has openings to allow a part of light to pass therethrough, and a pair of a light emitting section and a light receiving section which are provided opposite to each other with the light-shielding plate interposed therebetween and which moves integrally with the rotary base.

Abstract: A spherometer for measuring the radius of curvature of 1 lens is disclosed. The spherometer comprises a spherometer ring having an annular portion or a part of an annular portion, a measuring member coaxially secured to the spherometer ring, a supporting member for supporting the spherometer ring, and a tilt facilitating member interposed between the spherometer ring and the ring supporting member.

Abstract: A device for tracing a surface such as one defining the lens opening of an eyeglass frame includes a tracer element moved automatically about a rotational axis surrounded by the traced surface and arranged perpendicularly to the area enclosed by the surface. As this rotation occurs a carrier for the tracer element is moved along a second axis extending perpendicularly to the rotational axis in response to a position error signal developed by the tracer element to maintain the position error signal at a substantially zero value through the use of feedback circuitry. The positions of the carrier about the rotational axis and along the second axis are repeatedly captured during the tracing movement to provide point data defining the shape of the traced surface. Results are a smooth steady movement of the tracer element along the surface with a minimum amount of force being exerted on the traced surface by the tracer element.

Abstract: An inspection apparatus for measuring a surface contour on a workpiece, such as a groove in a pilgering roller die, includes a supporting mechanism for rotatably clamping the die so as to orient the groove thereon in a measurement position, an elongated contact member having a pair of arms with end elements extending in opposite directions, a pair of measurement devices each including a displaceable contact probe and electrical circuitry for measuring the displacement of the contact probe, and a spindle mounting the contact member in a generally vertical orientation and for movement about a vertical axis. End elements on the contact member arms are movable along orthogonally-disposed axes lying in horizontal planes and are respectively placed in contact with a contour of the die groove to be measured and the displaceable contact probes such that displacement of the probes permits measurement of the radius of the groove contour.

Abstract: An apparatus for checking features of workpieces with rotational symmetry defining a geometrical axis, which includes a base, rest devices fixed to the base for supporting the workpiece with the geometrical axis horizontally arranged, and a support structure coupled to the base for rotation about a horizontal axis. A counterweight and sensor are coupled to the support structure and movable with the support structure from a rest position, allowing loading of the workpiece to be checked onto the rest devices to a working position where the sensor is brought into cooperation with the workpiece. The axis of rotation of the support structure is arranged below the axis of the workpiece, in correspondence to a vertical geometrical plane passing through the workpiece geometric axis when the workpiece is positioned on the rest devices.