Reversing mechanism for the direction of rotation in a drilling apparatus

A reversing mechanism for the direction of rotation in a drilling apparatus comprising a feeding beam (1), a drilling machine (3) displaceably mounted on said feeding beam, and a feeding mechanism (4) for displacing said drilling machine along said feeding beams in a drilling direction (A) and in an opposite return direction (B), said drilling machine being provided with a pressure medium driven rotating device (9) for rotating a drilling rod (10) to be fastened to said drilling machine and with a reversing valve (13) connected to the pressure medium system of said rotating device and having a spindle (16) rotatable between two positions in which said rotating device rotates said drilling rod in opposite directions, and means for rotating said spindle into said positions, characterized in that said reversing mechanism (15) comprises two actuating elements (24,27) rotationally mounted with respect to each other, one (24) of said elements being in rotational engagement with the spindle (16) of said reversing valve (13) and moving axially with said spindle at least at the end of said return direction (B) of the drilling machine and the other (27) of said elements being arranged to maintain non-rotating and stationary at the end of said return direction (B) but to rotate and move axially with respect to said one actuating element (24) at the beginning of said drilling direction (A) of said drilling machine, and in that said actuating elements are provided with means (28,29) for forcing said actuating elements to rotate with respect to each other as they move in the axial direction of said spindle (16) with respect to each other.