| 摘要 |
PURPOSE:To make either feed for a drilling part and a tapping part alterable, by forming a feed screw in a hydraulic piston shaft, thereby turning the feed screw to a screw shaft, while using the hydraulic feed in combination with the screw feed, in case of a feed drive of a tapping device for a combined pipe tap and drill. CONSTITUTION:When a hydraulic cylinder device 21 operates and a casing 2 moves forward at a rapid traverse as well as when the tip of a combined pipe tap drill 7 comes close to a work 35, a carrier 23 pushes a flow regulating valve 24 into motion, switching it to drilling feed. When drilling is over, a carrier 25 also pushes a limit switch 26 into operation, stopping a piston of the hydraulic cylinder device 21. Therefore, a solenoid clutch 20 is excited whereby the turning force of a spindle 4 is transmitted to an internal thread body 15 via gears 19 and 18. When the internal thread body 15 rotates, the thread body 15 travels on a feed screw shaft 13 in its axial direction, and consequently a combined pipe tap and drill moves forward together with the casing 2 as far as the amount of travel commensurate to the pitch. |
