| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent noise caused by a collision between a draw bar and a counterweight, without arranging a soundproof member in the counterweight itself. <P>SOLUTION: The draw bar 4 has a locking part 41 mutually projecting in the opposite direction in the diameter direction from a peripheral side surface of a columnar part 40. The draw bar 4 also has a compression spring member 42 for energizing the draw bar 4 in the axial direction, on the upper end of the columnar part 40 so as to be fitted around the columnar part 40. While, the counterweight 3 is formed with an upper insertion hole 5 and a lower insertion hole 6 for inserting the draw bar 4 with an opening part 32 in-between. When inserting the draw bar 4 into the insertion holes 5 and 6, the draw bar 4 is energized in the opposite direction (the upward direction) of the insertion direction by the compressed spring member 42, and the draw bar 4 trying to slip out of the insertion holes 5 and 6 by being energized is locked on the counterweight 3, by the locking part 41, and thereby, the draw bar 4 is installed on the counterweight 5. <P>COPYRIGHT: (C)2012,JPO&INPIT |
