Patent GB-190114916-A (GB)
Title: Machines for Pointing and Threading Bolts
Inventor: JOHNSON CHARLES A
Filed: 1901-07-22
Granted: 1901-10-05
Abstract: 14,916. Johnson, C. A. July 22. Screwing; lathes. - A machine for pointing and screwing bolts has a hopper feed, and is provided with yieldi n g connections t o avoid fracture of the parts should the feed be imperfect. The hopper 22 is mounted on a block 7, and is constantly driven from a cam shaft 17 driven through gearing 16 from a belt pulley on a countershaft mounted in the tool-spindle bearings 3. The feedmechanism is carried by a block 6, the blocks 6, 7 being adjustable to or from the tools to suit different sizes of blanks. A picker 23 catches the blanks under the heads, and is oscillated by a rod 25 to allow them to slide down a shoot 28. A spring arm 24 prevents the picker from engaging too deeply in the mass of blanks. The blanks are separately released at the bottom of the shoot by escapement stops 30, 34, Fig. 8, which allow a blank to enter the feed - slide 38, which transfers it to one of a number of notched plates 49 on a carrier-plate 47. The escapement stops and feedslide are operated by a sleeve 32 driven through a spiral spring from an internal sleeve 43 on a rockshaft 42 operated from the cam shaft 17, the spring connection ensuring that a blank is fed to the carrier-plate only when the mechanism is correctly operated. The plates 49 have notches to suit various sizes or shapes of blanks, and are angularly adjustable on their centres on the carrier-plate, or a single plate, concentric with the carrier-plate, may be used. A guide-frame 58, with work supports 59 and adjustable screws (not shown) to rest on the blank heads, while being machined, retain the blanks in the carrier-plate till past the line of action of the tools. The carrier-plate is intermittently rotated by a disc (not shown) having a spring pawl engaging spaced notches in an indexplate fixed to the carrier-plate, the disc being rocked from the rock-shaft 42, which is positively moved in the idle stroke and returned by a spring 67, thus giving a yielding feed to the carrier-plate, which is held by a check pawl 69. Should the carrier-plate be insufficiently rotated to again engage the pawl 69, the friction of the spring feedpawl will return it, causing the blank being fed to be ejected by a pawl 74. Fig. 8. A guide 72 with a loop 73 arrests the blank should it be too long, and thus causes it to be returned and ejected. An oscillating support 76, Fig. 1, for long blanks supports the blanks during machining, and is rocked by a cam 79 on the cam shaft 17 to disengage the blank during the intermittent rotation. The support is returned by a spring which yields should the cam 79 fail in operation, and thus avoids tilting the blank excessively. The pointing-spindle 86 and screwing-spindle 88 are longitudinally reciprocated by a double-faced cam 81 and levers 82 held together by a spring, and are separately driven by belt pulleys 90, 92. The screwing-die is preferably of the " self-opening " type, the spindle 88 comprising a sleeve 93, carrying the pulley and die, and provided with a rod 108 on which a yoke 105 engaged by the operating-lever 83 can slide against the action of a spring 104, thus ensuring a gradual engagement of the die and blank. A die-operating rod 94 within the sleeve is pinned to a coned sleeve 100, between which and the pulley boss 101 is a bevelled ring 102, normally concentric with the sleeve 93. At a suitable time, a lever 110, Fig. 1, is operated by a cam 111 to press against the ring 102, thus retracting the coned sleeve and rod 94 to open the dies. To provide against failure of the cam 111, the pulley has a front cam 114 to act on an arm 113 of a supplemental lever 112 to actuate the lever 110. A suitably-notched plate is mounted on a short shaft moving with the carrier-plate, and prevents forward movement of the tools unless the carrierplate is in its correct angular position.