| 摘要 |
The present invention relates to a rotary drilling bit, which comprises a leg (1) with a journal (5) and a rotary cutter (3) rotatably mounted on the journal (5), which cutter carries rock cutting means (4), said rotary cutter (3) being rotatably mounted on the journal (5) by means of radial cylinder bearings (7, 9, 10, 11, 12, 13), said rotary cutter (3) being secured in the axial direction on the journal (5) by a flange (22), which cooperates with rolling elements of at least one of the radial cylinder bearings, and wherein also axial bearings (14, 15, 16) are provided between the rotary cutter (3) and the journal (5), and wherein means (24) for inserting rolling elements (7; 11) to a pair of races (9, 10; 12, 13) for forming a radial cylinder bearing is provided in the leg (1) after the rotary cutter (3) has been mounted to the journal (5), and wherein an element (25) to block said means (24) for inserting rolling elements is provided in connection with said means (24) for inserting rolling elements after completion of inserting the rolling elements. The flange (22) is provided with a recess (23), which allows passage of the rolling elements (7) that are mounted after mounting of the rotary cutter (3) to the journal (5). The element consists of a locking pin (25), which at its innermost end in the mounted position is provided with a lip (27), which occupies only a part of the cross-section of the locking pin (25). |
