Alfons Ernst has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
Abstract: A length measuring system having a scale with a first portion and a second portion separated by a gap, wherein the first and second portions each have incremental graduations. The system further includes a scanner unit for scanning the incremental graduations of the first and second portions, wherein the scanner unit has two groups of scanner elements spaced apart by a greater than the width of the gap. The system has at least one control track parallel to and next to the incremental graduations of the first and second portions. A further scanner element is provided to scan the at least one control track and produce an output signal, wherein the output signal is a function of the absolute position of the first and second portions and controls a switchover from one group of scanner elements to the other group of scanner elements.
Abstract: A multi-coordinate probe including a housing, at least one tracer pin for scanning an object and deflectable in a plurality of coordinate directions upon engagement with the object, and a support for supporting the tracer pin in the housing and formed of a plurality of multi-arm leaf springs having each at least one axially extending spring component.
Abstract: A multi-coordinate probe includes at least one tracer pin for scanning an object and deflectable in a plurality of coordinate directions upon engagement with the object, and a plurality of sensors for detecting deflection of the tracer pin and having their respective measuring axes intersecting at the scanning pole, defined by the tracer pin.
Abstract: An incremental angle encoder of the invention has an encoder shaft connected with a first disk having an incremental angular graduation and a first and a second reference mark. A second disk is connected to this first disk via a reduction gear, on which a spiral-shaped reference scanning field is provided. A first scanning unit scans the incremental angular graduation to generate two scanning signals and the first reference mark to generate a first reference signal. A second scanning unit scans the second reference mark utilizing the spiral-shaped reference scanning field to generate a second reference signal. A specific offset, which indicates the number of revolutions of the encoder shaft, exists between the first reference signal and the second reference signal because of the spiral-shaped reference scanning field. An absolute angular measurement value for the encoder shaft is determined from the scanning signals and from the specific offset for the number of revolutions.
Abstract: A measuring device is provided in which a graduated plate is scanned in at least two scanning locations. The scanning signals from the different scanning locations are transmitted to a testing circuit which determines whether the phase displacement between the scanning signals exceeds a limit value. If the limit value is exceeded, one of the scanning locations is weighted higher than the other. The weighting is implemented by increasing the components of the signals from one scanning location while decreasing the components from the signals from the other scanning location.
July 22, 1988
Date of Patent:
February 5, 1991
Dr. Johannes Heidenhain GmbH
Alfons Ernst, Walter Schmitt, Norbert Huber
Abstract: A photoelectric angle measuring apparatus for measuring relative angular positions of two objects which are rotatable relative to each other. The apparatus includes a scanning unit with a scanning scale connected to one of the objects. The scanning unit scans an angle scale of a scale carrier which is connected to the other object. Corresponding graduations of the scanning scale and the angle scale extend parallel to each other. The scanning unit includes an optically projecting element for the light ray path. The optically projecting element has a focal point which is located on the axis of rotation of the scale carrier or a focal line which coincides with the axis of rotation of the scale carrier.
Abstract: A position measuring device including an adjusting device for a sensing device of a graduation. The sensing device is adjustable relative to the graduation by the adjusting device. For the adjustment, the sensing device has three oblong holes whose longitudinal axes extend perpendicularly to each other. A cylindrical pin fixed in the adjusting device engages in one of the oblong holes. Two adjusting screws which have eccentric portions and engage in the oblong holes are used for adjusting the adjusting device in radial and tangential directions, so that the sensing device can be adjusted exactly relative to the graduation of the position measuring device.
Abstract: A position measuring device for measuring the relative position of two objects (01, 02) comprising a graduation (Ta) in a graduation plane (TFa) of the graduation carrier (TTa) which is connected to one of the objects (01). The object (01) is scanned by a scanning unit (A) which is connected to the other object (02) by means of a carrier (MT). Between the carrier (MT) and the scanning unit (A), a coupling link (K), preferably in the form of a leaf spring, is aligned in the direction of measurement X. This spring has only one rotational degree of freedom in a direction perpendicular to the graduation surface (TFa) of the graduation carrier (TTa). A guide mechanism (F) comprises a guide element (FE) which guides the scanning unit (A) in a direction parallel to the direction of measurement X on a guide surface (FFa) of the graduation carrier (TTa). The guide surface (FFa) is perpendicular to the graduation surface (TFa) of the graduation carrier (TTa).
Abstract: A position measuring device for measuring the relative positions of two objects, wherein the two objects are machine components of a processing or working machine or a measuring machine for tools. The graduation of a scale connected to the first object is scanned by a scanning unit connected to the second object. The scale is arranged on a scale carrier so as to be slightly displaceable in a measuring direction. The scale carrier is connected with both ends thereof to fastening elements which, in turn, are rigidly connected to the first object. When the scale, the scale carrier and the workpiece have different thermal expansion, the scale carrier is connected at least at one end thereof to the fastening element with a translatory degree of freedom in measuring direction. The scale is biased at least at one end thereof by a spring element. The spring element is connected to the translatory movable end of the scale carrier.
Abstract: In a switching multi-coordinate probe an accurate and accurately reproducible switching behavior is attained by a plurality of seating points, which all have the same elasticity but also a relatively high stiffness. The bearing members (14) and their counterbearing support members (16) exhibit an adequate number of degress of freedom, in order to be able to accurately align themselves with respect to each other during assembly. After adjustment the contact zones of the individual bearing members (14) form with their counterbearing support members (16) circular lines, which all lie in one plane with respect to the stylus axis (FIG. 1).
Abstract: A measuring system is disclosed which is integrated into a feed arrangement in such a way that the structural size of the feed arrangement is not increased significantly. In the disclosed embodiments, the feed arrangement includes a compressed air cylinder which includes a hollow profile and a piston movable within a cylinder defined by the profile. In one embodiment, a measuring scale is positioned within a groove formed within the hollow profile and this measuring scale defines a magnetic measuring graduation which is scanned by a scanning unit accommodated in the piston of the air cylinder.
Abstract: A photoelectric measuring system for detecting an oscillation pattern produced by a light measuring apparatus and generating harmonic free electrical output signals up to a predetermined band width. Any number of harmonics may be eliminated by selecting the size, shape, and position of a plurality of photoelements with respect to the oscillation pattern detected.
Abstract: In a switching multicoordinate probe an accurate and accurately reproducible switching behavior is achieved by a plurality of bearing points, which all have the same elasticity. The bearing balls (14) and their countermembers (17) exhibit a sufficient number of degrees of freedom, in order to be able to accurately orient themselves with respect to each other during installation. After adjustment the contact zones of the individual bearing balls (14) with the inclined sectional surface (18) of their countermembers (17) form an accurate bearing arrangement for the probe retainer (10), which bearing arrangement lies in a plane prependicular to the stylus access (FIG. 1).
Abstract: A length- or angle-measuring arrangement for measuring the relative position of two objects. A graduation (Ta) lies in a graduation plane (TEa) of a graduation carrier (TTa) which is connected with one of the objects outside the neutral plane (NEa) of the graduation carrier (TTa). The graduation carrier (TTa) is scanned by means of a scanning graduation (ATa) in a scanning graduation plane (ATEa) of a scanning unit (Aa) which is connected with the other object. To eliminate measuring errors brought about by bendings of the graduation carrier (TTa), the scanning graduation (ATa) of the scanning unit (Aa) is arranged in the neutral plane (NEa) of the graduation carrier (TTa).
Abstract: A multistage angle encoder includes a fine code disc which is connected via a reducing gear with at least one coarse code disc. In order unambiguously to allocate the coarse code information on the coarse code disc to the fine code information on the fine code disc, control information data is applied to the fine code disc to directly superimpose on the coarse code information of the coarse code disc. The control code information is provided in each case on two concentric control half-tracks of the fine code disc, and the coarse code information is provided in each case on two concentric coarse code half-tracks of the coarse code disc. The superposed coarse code half-tracks and control half-tracks are scanned in common by means of a single scanning field of the scanning plate.
Abstract: A measuring instrument for determining the absolute angular position of two rotatable objects. The instrument comprises a housing which encapsulates a first information carrier with an incremental scale, a second information carrier with a absolute scale, a revolution reduction unit mechanically connecting the second carrier to the first carrier and a scanning element for scanning the first and second information carriers. The angle of rotation is determined within 360.degree. by means of the incremental scale and the number of revolutions of the first information carrier is absolutely determined within the range of i.times.360.degree. from the absolute scale, wherein i represents the ratio of the revolution reduction unit.
Abstract: A position measuring system includes for the determination of a reference position at least one additional reference scanning unit which is shiftable relative to the measuring scale, independently of the measuring scanning unit and the measuring scale, and accordingly of the machine components connected to the measuring scanning unit and the measuring scale. The measuring scale carries an incremental graduation and a reference mark, and the measuring scanning unit and the reference scanning unit carry indicator blocks which on coincidence form a zero indicator. In order to determine the reference position, the reference marks and the zero indicator are scanned successively, but in arbitrary sequence, and their differential spacing is determined with the aid of a graduation of the reference scanning unit.
Abstract: In a position measuring system for measuring the relative position of two objects, a scale having a graduation with a graduation period P is scanned by a scanning unit in order to generate a periodic analog signal having a bandwidth N. In order to generate harmonic-free Fourier coefficients of the fundamental wave of the periodic analog signal, a scanning plate included in the scanning unit includes a first scanning group with first and second scanning fields as well as a second scanning group with first and second scanning fields. The first scanning group is offset with respect to the second scanning group by P/4. The first scanning fields are offset with respect to the second scanning fields by P/2. Each scanning field includes N partial fields which are offset with respect to one another by P/2N in the measuring direction. The widths of the partial fields are varied in the measuring direction according to a sine function.
Abstract: A multicoordinate sensing head is disclosed in which a sensing pin is secured in the interior of a sensing head housing by means of a flange which is rigidly secured to the pin. The flange rests on precisely formed bearing balls which are distributed uniformly around the circumference of an opening in the bottom of the housing through which the pin passes. A rim on the flange extends around the bearing balls to grip the balls and prevent radial shifting of the sensing pin. In the rest position, into which the sensing pin is pressed by the action of the spring operating via a sensor probe, the free end of the sensing pin is precisely positioned in a predetermined orientation with respect to the housing in a repeatable and accurate manner. When the sensing pin is deflected, the flange tilts around one or two of the balls and thereby moves the sensor probe axially to allow a measurement system to sense deflection of the sensing pin.