Devices for withdrawing props or chocks

Industry

  • CPC
  • E21D15/60
This industry / category may be too specific. Please go to a parent level for more data

Patents Grantslast 30 patents

  • Information Patent Grant

    Base mechanism of single prop capable of being unloaded at reduced...

    • Patent number 10,895,154
    • Issue date Jan 19, 2021
    • China University of Mining and Technology
    • Qiang Zhang
    • A47 - FURNITURE DOMESTIC ARTICLES OR APPLIANCES COFFEE MILLS SPICE MILLS SUCT...
  • Information Patent Grant

    Mechanical constant-resistance single prop continuous prop lifting...

    • Patent number 10,844,717
    • Issue date Nov 24, 2020
    • China University of Mining and Technology
    • Yanlong Chen
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    Process method for withdrawing and recovering mechanical constant-r...

    • Patent number 10,352,167
    • Issue date Jul 16, 2019
    • China University of Mining and Technology
    • Jixiong Zhang
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    Method for removing hydraulic support for solid filling coal mining

    • Patent number 10,036,252
    • Issue date Jul 31, 2018
    • China University of Mining and Technology
    • Feng Ju
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    3295814

    • Patent number 3,295,814
    • Issue date Jan 3, 1967
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    3191506

    • Patent number 3,191,506
    • Issue date Jun 29, 1965
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    3136534

    • Patent number 3,136,534
    • Issue date Jun 9, 1964
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    3077741

    • Patent number 3,077,741
    • Issue date Feb 19, 1963
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    3012404

    • Patent number 3,012,404
    • Issue date Dec 12, 1961
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2997272

    • Patent number 2,997,272
    • Issue date Aug 22, 1961
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2904301

    • Patent number 2,904,301
    • Issue date Sep 15, 1959
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2816728

    • Patent number 2,816,728
    • Issue date Dec 17, 1957
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2723100

    • Patent number 2,723,100
    • Issue date Nov 8, 1955
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2677535

    • Patent number 2,677,535
    • Issue date May 4, 1954
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2647736

    • Patent number 2,647,736
    • Issue date Aug 4, 1953
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2621631

    • Patent number 2,621,631
    • Issue date Dec 16, 1952
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2606745

    • Patent number 2,606,745
    • Issue date Aug 12, 1952
    • B66 - HOISTING LIFTING HAULING
  • Information Patent Grant

    2597807

    • Patent number 2,597,807
    • Issue date May 20, 1952
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2498060

    • Patent number 2,498,060
    • Issue date Feb 21, 1950
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2430962

    • Patent number 2,430,962
    • Issue date Nov 18, 1947
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2301489

    • Patent number 2,301,489
    • Issue date Nov 10, 1942
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2190556

    • Patent number 2,190,556
    • Issue date Feb 13, 1940
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2149889

    • Patent number 2,149,889
    • Issue date Mar 7, 1939
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2068491

    • Patent number 2,068,491
    • Issue date Jan 19, 1937
    • B66 - HOISTING LIFTING HAULING
  • Information Patent Grant

    2047537

    • Patent number 2,047,537
    • Issue date Jul 14, 1936
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    1924477

    • Patent number 1,924,477
    • Issue date Aug 29, 1933
    • B66 - HOISTING LIFTING HAULING
  • Information Patent Grant

    1858954

    • Patent number 1,858,954
    • Issue date May 17, 1932
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    1805381

    • Patent number 1,805,381
    • Issue date May 12, 1931
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    1774308

    • Patent number 1,774,308
    • Issue date Aug 26, 1930
    • B66 - HOISTING LIFTING HAULING
  • Information Patent Grant

    1752101

    • Patent number 1,752,101
    • Issue date Mar 25, 1930
    • E21 - EARTH DRILLING MINING

Patents Applicationslast 30 patents