| 摘要 |
888,026. Fluid-pressure blasting devices. MARMON-HERRINGTON CO. Inc. June 14, 1960 [Sept. 14, 1959], No. 20811/60. Class 9(1). In the blasting device of Specification 872,753 modifications are made to the valve controlling the gas discharge, to prevent reclosure of the discharge valve until the release chamber is completely discharged and during the supply of gas to the release chamber.
|
