Patents by Inventor Manfred Kretschmer

Manfred Kretschmer 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: 7252203
    Abstract: A mobile crane with a carrier and a superstructure which is slewably arranged thereon has a superlift device with an SL counterweight for increasing lifting capacity. The SL counterweight can be lifted from the ground in order to execute slewing movements of the superstructure and its slewing radius is changeable. The crane has an electronic control device with a computing device and with a display. In order to avoid costly conversion work on the SL counterweight and to increase operating safety, a program is stored in the electronic control device, which program determines a permissible operating field for crane parameters from the parameters comprising load size and load radius, size of SL counterweight and SL counterweight radius while taking into account the stability criteria and capacity criteria of the mobile crane and displays this operating field graphically on the display.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: August 7, 2007
    Assignee: Terex-Demag GmbH & Co. KG
    Inventors: Ralf Frankenberger, Jörg Lattwein, Manfred Kretschmer
  • Publication number: 20050098520
    Abstract: A mobile crane with a carrier and a superstructure which is slewably arranged thereon has a superlift device with an SL counterweight for increasing lifting capacity. The SL counterweight can be lifted from the ground in order to execute slewing movements of the superstructure and its slewing radius is changeable. The crane has an electronic control device with a computing device and with a display. In order to avoid costly conversion work on the SL counterweight and to increase operating safety, a program is stored in the electronic control device, which program determines a permissible operating field for crane parameters from the parameters comprising load size and load radius, size of SL counterweight and SL counterweight radius while taking into account the stability criteria and capacity criteria of the mobile crane and displays this operating field graphically on the display.
    Type: Application
    Filed: September 20, 2002
    Publication date: May 12, 2005
    Inventors: Ralf Frankenberger, Jorg Lattwein, Manfred Kretschmer
  • Patent number: 6568547
    Abstract: A crane, especially a self-propelled crane, with a base structure and a revolving superstructure mounted thereon, a boom and a mast being hinged to the superstructure. The tip of the mast is connected on one side via adjustable-length guying to the head of the boom and on the other side via guying to a counterweight. The crane is not provided with a separate superstructure counterweight. The distance between the counterweight and the superstructure of the crane is continuously variable within a fixed range by a frame element, which can move in the vertical place, is mounted on the superstructure, and is connected thereto in a gravity-actuated (nonpositive) manner, The frame element is connected to an apparatus for directing the resulant of the force of the counterweight acting in the direction of gravity and the guying force produced by the suspended load into the superstructure.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: May 27, 2003
    Assignee: Atecs Mannesmann AG
    Inventors: Manfred Kretschmer, Alfons Weckbecker
  • Patent number: 6516961
    Abstract: A ringlift crane having a ring which can be elevated, forms an annular track and has a plurality of segments which can be connected to one another, there being arranged within said ring an undercarriage which has an upper carriage, which is connected for slewing action to the undercarriage and has a plurality of hoisting winches. Two trusses which are spaced apart parallel to one another, are provided, in two mutually opposite end regions, with in each case one adapter and can be bolted to, and unbolted from, the upper carriage via crossmembers. The adapters are supported with rolling action on the annular track of the ring by rollers arranged in the end region of the adapters. For the purpose of setting different modes of operation of the crane, the trusses can be raised relative to the basic machine and connected in different ways to the crossmembers.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: February 11, 2003
    Assignee: Atecs Mannesmann AG
    Inventors: Alexander Knecht, Manfred Kretschmer, Michael Biermann, Ralf Frankenberger
  • Patent number: 6474487
    Abstract: A ringlift crane having a ring which can be elevated and forms an annular track. Arranged within the ring is a standardized undercarriage from a first crane class and a standardized upper carriage, which is connected for stewing action to the undercarriage and has a plurality of hoisting winches. The upper carriage is connected to one adapter in both end regions. The adapters are supported with rolling action on the annular track of the ring by rollers. The center point of the ring and/or of the undercarriage forms the stewing axis. One adapter is designed for accommodating a counterweight and the other adapter is designed as a load-bearing element for the main boom and the mast (counter-boom) which can be articulated at the free end of the adapter. The top of the mast is connected, on the one hand, to the counterweight via a stay cable and, on the other hand, to the head of the main boom via a changeable-length cable stay.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: November 5, 2002
    Assignee: Mannesmann AG
    Inventor: Manfred Kretschmer