| 摘要 |
<p>As in the prior art, the apparatus comprises means connectible with the piece to form an anvil for the transmission of impact forces to the piece axially the driven path thereof, and a ram which is mounted on a support to reciprocate on a parallel to the driven path of the piece adjacent the anvil, and which is reciprocated and impacted against the anvil to drive the piece along the path thereof. However, according to the invention, the ram has a hollow chamber operatively enclosed therewithin, and is driven by means which are connected with the chamber to reciprocate the ram, and if desired, to accelerate it against the anvil as well, by way of driving the piece as indicated. In this way, the ram can undergo a shorter stroke, thus shortening the length of the apparatus along the aforesaid parallel to the path of the piece. This in turn leads to certain other features and advantages, as well as to certain additional structural combinations which are made possible by it.</p> |
