3143862

Information

• Patent Grant
• 3143862

• References
• Source

• Patent Number

  3,143,862

• Date Filed

  Not available

• Date Issued

  Tuesday, August 11, 1964
  60 years ago

• CPC

  • E21D23/06 - Special mine caps or special tops of pit-props for permitting step-by-step movement
  • E21D15/585 - by means of hydraulically operated devices for mechanical props, or hydraulic props in which the hydraulic part is not important
  • E21D23/0073 - with advancing shifting devices connected therewith
  • E21D23/0481 - Supports specially adapted for use in combination with the placing of filling-up materials

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 091 - Motors: expansible chamber type
  • 299 - Mining or in situ disintegration of hard material