发明名称 |
Pickup truck derrick with traveling sheaves |
摘要 |
A portable derrick assembly adapted for mounting on a pickup truck or a trailer, includes a base frame, a derrick tower, a tower erection subassembly, and an elongated boom pivotally mounted on the tower. A traveling sheave and cable subassembly interconnects a tail end of the boom with the tower for pivoting the boom about a pitch axis. A hoist cable is raised and lowered by a hoist traveling sheave subassembly mounted on the boom.
|
申请公布号 |
US5016768(A) |
申请公布日期 |
1991.05.21 |
申请号 |
US19890430884 |
申请日期 |
1989.11.02 |
申请人 |
KENNARD, JR., DAVID C.;KENNARD, JAMES C. |
发明人 |
KENNARD, JR., DWIGHT C.;KENNARD, JAMES C.;WICK, CARL J. |
分类号 |
B66C23/34;B66C23/36;B66C23/60 |
主分类号 |
B66C23/34 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|