Pressure operated heavy duty drill head - has spring loaded stops and switches to produce automatic fast and slow feed cycle (SW 4.4.77)

摘要

The drilling head has a spindle (5) in a carriage (3) mounted on wheels (2). A hydraulic cylinder (8, 25) operates the spindle below which a rod (14) is fixed to the carriage and slides in stops on the base. Discs (15) locate springs (22, 23) which butt against each side of one stop (21)). The drill (7) advances at fast feed and contacts the work (W). This pushes the carriage rearwards (4a) to the fixed stop (17, 18). A switch (19) is energised and a time delay (26) actuates the slow feed. When relieved of pressure, as the drill breaks through, the carriage is moved forwards by the spring and a switch (20) retracts the spindle.