Patents by Inventor Robert Lisfeld

Robert Lisfeld 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).

  • Patent number: 4733954
    Abstract: A microscope support foot (10) includes a central portion (14) and two lateral portions (15, 16), which form receiving chambers (19, 20, 21) by means of separating walls (17, 18) extending as far as a base plate (23). The optical components for an illumination arrangement (28) are disposed in receiving chamber (20) so as to be protected from dust by a seal (25), and the electronic components are disposed in a heat-dissipating manner in the receiving chamber (21), so that the heat-emitting components are in contact with the base plate (23) which is made of heat-dissipating material. This base plate and the lateral portion (16) have ventilation slits (42, 42'). A drive unit (36) for the adjustment of the successviely arranged aperture stop and light field stop (30, 31) is secured in the receiving chamber (19) in such a manner that the adjusting arrangement is accessible from outside and is disposed at a convenient distance from a focussing arrangement (13).
    Type: Grant
    Filed: June 2, 1986
    Date of Patent: March 29, 1988
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Guenter Reinheimer, Karl Wieber, Robert Lisfeld, Walter Voigt
  • Patent number: 4575199
    Abstract: The drive has a manual coarse/fine focusing device using a gear drive and additional fine focusing using a motor. The latter is effected through an eccentric cam, rotatingly supported in a guide plate and coupled with the motor. A ball bearing rigidly joined with the object holder and the microscope stage rests on the eccentric cam. During operation of the motor, only the ball bearing and, thus, the microscope stage are raised or lowered; the gear drive for manual focusing remains stationary.
    Type: Grant
    Filed: April 25, 1983
    Date of Patent: March 11, 1986
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventor: Robert Lisfeld
  • Patent number: 4572614
    Abstract: A microscope condenser housing having an annular slit to receive filter slides, which during their insertion are arrested in two defined positions. A locking device effective against the outward motion of the filter slides and additionally locking the filter slides in at least one of the defined positions is provided. Incorrect inverted insertion of the filter slides is also prevented. The locking by the locking device is readily released manually by means of a locking lever projecting from the condenser housing.
    Type: Grant
    Filed: March 12, 1984
    Date of Patent: February 25, 1986
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Robert Lisfeld, Edwin Diehl
  • Patent number: 4402576
    Abstract: An adjusting device for the specimen stage of an optical instrument such as a microscope or vernier measuring instrument comprising a pair of superposed slides mounted for movement in two mutually perpendicular coordinate directions perpendicular to the optical axis of the instrument with coaxial drive means for effecting fine adjustments of the positions of the slides and with a single, common release mechanism for simultaneously disengaging both drive means to facilitate rapid manual displacement of the slides to an approximate desired position.
    Type: Grant
    Filed: July 9, 1981
    Date of Patent: September 6, 1983
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Werner Stahl, Walter Frobose, Robert Lisfeld
  • Patent number: 4372650
    Abstract: A microscope objective mount is described for screwing onto a microscope, said microscope having a tube which is rotatable around the mount and is held onto the mount. The mount is distinguished in that the tube extends over approximately the entire length of the mount, with the tube and mount being releasably connected together by a catch connection.
    Type: Grant
    Filed: September 19, 1980
    Date of Patent: February 8, 1983
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Robert Lisfeld, Reinhold Bender
  • Patent number: 4284327
    Abstract: Disclosed is a microscope adapted for accepting one or more attachment illuminating devices, which have different dimensions and are designed to be supplied with electric power either from a source within the microscope or external to the microscope. The microscope comprises a microscope stand comprising a base and a vertical support member; at least one source of electrical energy located inside of the stand for powering an illuminating device; and first means, associated with the stand, for connecting any of a variety of attachment illuminating devices which have different dimensions and are designed to be supplied with electric power either from the electrical energy source or from an electrical energy source external to the microscope.
    Type: Grant
    Filed: January 25, 1980
    Date of Patent: August 18, 1981
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Winfried Kraft, Robert Lisfeld, Willi Hagner, Karl Wieber, Horst Frimmel
  • Patent number: 4283111
    Abstract: Disclosed is a microscope stand which permits a lens turret and an eyepiece mounted on the stand to be mounted close enough together to eliminate the necessity of an intervening tube lens. In permitting this mounting of the lenses, a recess is provided in the stand which substantially weakens the mounting structure. Vertical webs are provided in the preferred embodiment which extend adjacent the recess and external to the lens turret which strengthen the microscope stand and mounting structure.
    Type: Grant
    Filed: January 28, 1980
    Date of Patent: August 11, 1981
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Karl Wieber, Heinrich Janke, Winfried Kraft, Robert Lisfeld
  • Patent number: 4166671
    Abstract: An apparatus for varying the position of a field stop with respect to a microscope substage illuminator includes a carrier for slidably mounting the field stop on the illuminator so as to move in a direction transverse to the optical axis of the illuminator. An annular element controlling the aperture of the field stop is pivotally mounted within the carrier and is coupled to a knurled ring projecting radially and upwardly from the diaphragm carrier. The knurled ring is in turn pivoted within the diaphragm carrier and preferably carries a circular line inscribed thereon which is concentric with the field stop in order to facilitate adjustment of the field stop.
    Type: Grant
    Filed: June 15, 1977
    Date of Patent: September 4, 1979
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Robert Lisfeld, Karl Wieber, Hans-Werner Stankewitz
  • Patent number: 4136927
    Abstract: A universal microscope condenser includes a supporting member having a fixed lens mounted thereon. A pivot arm is pivoted to the supporting member and a first lens member mounted on the pivot arm for movement by the pivot arm into optical alignment with the fixed lens. The supporting member also includes a carrier slide which has a second lens member mounted thereon. The first and second lens members can be switched in and out of optical alignment with the fixed lens to vary the aperture and luminous field of the universal microscope condenser. Also included is a variable aperture stop disposed between the first and second lens members. Preferably, the first lens member moves along an arcuate path which intersects the optical axis of the fixed lens and the second lens member moves along a path which is tangent to the arcuate path of the first lens member when the first lens member is aligned with the optical axis of the fixed lens.
    Type: Grant
    Filed: June 15, 1977
    Date of Patent: January 30, 1979
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventor: Robert Lisfeld
  • Patent number: 4111530
    Abstract: A novel and advantageous microscope objective mount is provided. Said mount can be screwed to a microscope and more particularly to the objective turret or nosepiece. It is provided with a rotatable outer sleeve held on the mount, the sleeve being held by an elastically deformable ring which engages, at least in part, by force-locking. Due to the construction of the mount of this invention, attachment of the sleeve thereto is considerably facilitated and improved with respect to the axial play as compared with known mount assemblies. There is practically no radial clamping of the holding ring against the mount.
    Type: Grant
    Filed: December 3, 1976
    Date of Patent: September 5, 1978
    Assignee: Ernst Leitz Wetzlar GmbH
    Inventors: Werner Fuehrer, Richard Huttel, Robert Lisfeld, Karl Leonhardt, deceased
  • Patent number: 4090069
    Abstract: A semi-automatic coarse-fine focusing apparatus for microscopes adjusts the focus of a microscope through rotation of a shaft which rotates a pinion that drives a rack to reciprocate. The rack carries a specimen being observed by the microscope. The shaft which rotates the pinion is in turn driven by a gear that is meshed with a helix formed on a cylinder by a helical thread disposed therearound. The helix is non-rotatably mounted on another shaft that includes a knob which is manually turned to turn the helix and thus rotate the gear for coarse adjustment. The helix is preferably rigidly mounted on the shaft and the shaft is slidable. One arm of a bell crank engages an end face of the helix to reciprocate the helix and thus rotate the gear for fine adjustment. The other arm of the bell crank is engaged by a cam which pivots the bell crank according to the position of the cam. The position of the cam is determined by an electric motor which is preferably controlled by signals that vary with image contrast.
    Type: Grant
    Filed: June 16, 1977
    Date of Patent: May 16, 1978
    Assignee: Ernst Leitz Wetzlar GmbH.
    Inventors: Robert Lisfeld, Werner Nickel, Guenter Reinheimer