| 摘要 |
The invention relates to a method and a device for releasing a block on a bore-crown (1) during a boring process, especially percussion boring or rotary percussion boring, for boring holes in the ground or rock, whereby a borehole is formed by a bore-crown (1) mounted on a boring rod (2) and connected thereto and acted upon by the boring rod to generate a rotational movement and optionally a percussive movement. According to the invention, when the bore-crown (1) is blocked, preventing the continuation of the boring process and especially another rotational movement of the bore-crown (1), the bore-crown (1) is subjected to a linear movement in the opposite direction to the boring direction by means of the boring rod (2), and to a rotational movement in a direction opposing the direction of the rotational displacement during the boring process by means of a corresponding connection (7, 9) between the end of the boring rod (2) facing the bore-crown (1), and the bore-crown (1), independently of a rotary drive for carrying out the boring process. As a result the borehole can be bored in a simple manner after releasing the block on the bore-crown (1). |
