Patents by Inventor Ludwig Drechsel

Ludwig Drechsel 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: 4739593
    Abstract: The terrace glasswork, which is particularly simple to adapt to building conditions, contains the following features: (a) It is made up of a vaulted roof, which is supported above on an existing wall and below on the terrace floor; as well as two gable parts. (b) The roof is made up along its length of several identical, glassed in arch components, the side frame parts of which can be joined and sealed to one another. Each of the latter has two movable glass panes (17, 20) guided so as to slide at different levels. (c) The gable parts are each made up of three gable components, namely of a square basic component (4) and two connecting components (5a, 6a) each of which to the arch components, and which connects together two right-angled frame sides of the basic component (4).
    Type: Grant
    Filed: October 24, 1986
    Date of Patent: April 26, 1988
    Inventors: Bernhard Janke, Ludwig Drechsel
  • Patent number: 4655152
    Abstract: A thread clamp for sewing machines comprises a helical spring as a clamping element which is disposed in a bore extending crosswise to the feed direction of the work in a guide piece placed on the stitch plate. To obtain a very short closing path, the helical spring has in the region of the respective thread pull-off path windings whose mutual distance is greater than in the other regions. The helical spring is compressible by a setting drive for the fixed clamping of the threads.
    Type: Grant
    Filed: May 1, 1986
    Date of Patent: April 7, 1987
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Eugen Angele, Ludwig Drechsel
  • Patent number: 4461229
    Abstract: A device is disclosed for pulling out and cutting off the needle and looper threads in a sewing machine with a delivery roller for delivering material to the machine sewing station. The delivery roller is driven over a first drive, which is dependent on the sewing machine main drive and over a second drive, which is independent of the sewing machine main drive. On the looper of the sewing machine is secured a cutting blade for the needle thread. Furthermore, a needle thread clamp is provided. In order to manage, with a single means for pulling out the needle and looper threads by different lengths, a cutting device for the looper thread is arranged between the cutting blade and the delivery roller, with a guide which is traversed by a thread inlet groove and with a counterknife for a thread severing knife that moves transverse to the material feeding direction. The delivery roller is driven over the second drive for pulling out the threads.
    Type: Grant
    Filed: March 17, 1982
    Date of Patent: July 24, 1984
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Eugen Angele, Ludwig Drechsel
  • Patent number: 4401368
    Abstract: A projecting screen for optical purposes which meets the stringent requirements for the reproduction of macroscopic as well as microscopic images in transmission operation. The object comprises providing a projection screen comprising several scattering media movable in relation to each other, by which projected images may be reproduced free of grain- and flickering- or scintillation effects, under simultaneous improvement of the resolution and the transmission qualities. The substance of the invention comprises a projecting screen in which two solid inorganic or organic media are movably assembled in relation to each other, of which one or both may be light-scattering because of surface roughness on one side, and a liquid flowing between these two means which may or may not have a scattering effect. This invention is of multiple use in the construction of scientific instruments.
    Type: Grant
    Filed: October 8, 1981
    Date of Patent: August 30, 1983
    Assignee: Jenoptik Jena GmbH
    Inventors: Ludwig Drechsel, Margarete Lasch