Patents Assigned to C. E. Johansson AB
  • Patent number: 6176018
    Abstract: A measuring machine produces an essentially linear movement in a moving part by transforming rotary movement to linear movement through a transmission element having a high modulus of elasticity in a longitudinal direction, and which is flexible in a transverse direction. The transmission element has two ends which are each fastened to the same mechanical element, and the transmission element is given a pre-stress which is greater than a maximum force encountered during acceleration while the machine is in use.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: January 23, 2001
    Assignee: C. E. Johansson AB
    Inventor: Rudolf Wiklund
  • Patent number: 5287629
    Abstract: A machine stand and a method of constructing it particularly a machine stand for so-called coordinate measuring machines. The machine includes one or more vertical legs, one or more horizontal beams, and a rod or bar which is mounted on a horizontal beam and intended to carry a measuring head tool or the like. At least one vertical leg is supported by a base element. The vertical leg supports at least one beam, and the rod can be moved to any selected point within the space volume defined by the stand by moving the leg, the beam and the rod relative to the base element. At least one vertical leg is mounted relative to the base element so as to be flexurally rigid and non-rotatable about its longitudinal axis; the beam or beams are not non-rotatably and flexurally rigidly connected, so that a yielding structure is obtained. Deformation of the first vertical leg is measured by measuring means, so as to be able to determine deformation of the structure.
    Type: Grant
    Filed: July 1, 1992
    Date of Patent: February 22, 1994
    Assignee: C. E. Johansson AB
    Inventor: Bo Pettersson
  • Patent number: 5189807
    Abstract: A method for determining and, when appropriate, compensating for the linear (heat) expansion of elongated bodies (1), such as physical length scales (1) or of elongated bodies which are intended to support physical length scales on, e.g., instruments or measuring machines equipped with physical length scales, in which measurement errors occur because of length deviations of the scale (1) as a result of deviations from a reference temperature at which the scale was calibrated.The method is mainly characterized by measuring the linear expansion of the body (1) in relation to at least one reference (6) made of a material whose coefficient of linear (heat) expansion (.alpha.) deviates from the coefficient of linear (heat) expansion of the body material, and thereafter determining, when appropriate, a compensation factor for correcting the body length.The invention also relates to an arrangement for carrying out the method.
    Type: Grant
    Filed: February 3, 1992
    Date of Patent: March 2, 1993
    Assignee: C. E. Johansson AB
    Inventor: Carl-Erik Gustafsson
  • Patent number: 5062214
    Abstract: An absolute measuring scale system comprising a scale which extends along a measuring length, and a measuring head which is movable relative to the scale. The system further includes a fine-measurement sensor which is intended to measure the absolute values within each of a multiple of intervals lying sequentially along the scale, and a coarse-measurement sensor intended to measure the absolute values with regard to the interval within which the fine-measurement sensor is located at that moment. The invention is characterized in that the scale (2) comprises a carrier made of a transparent and form-stable material, preferably glass, which has provided on its surface an outer coating or layer which forms an opaque pattern (3, 4). The pattern formed along the length of the scale (2) forms transparent, mutually parallel binary code tracks (12), preferably in accordance with the so-called Grey-code.
    Type: Grant
    Filed: April 12, 1990
    Date of Patent: November 5, 1991
    Assignee: C. E. Johansson AB
    Inventors: Carl-Erik Gustafsson, Bo Pettersson
  • Patent number: D268739
    Type: Grant
    Filed: February 12, 1981
    Date of Patent: April 26, 1983
    Assignee: C. E. Johansson AB
    Inventor: Jan Hampf