Patent GB-977435-A (GB)
Title: Improved automatic stud producing machine
Inventor: GRUNDY RICHARD
IPC: B23Q7/06
Filed: 1962-07-20
Abstract: 977,435. Machine-tool details; thread-rolling. REID & SIGRIST Ltd. July 16, 1963 [July 20, 1962], No. 27921/62. Headings B3B, B3M and B3T. An automatic stud-producing machine comprises tool-heads q 1 , q 2 , r 1 , r 2 , work-holders # 1 - # 4  at the tool stations 3-6, a work-transfer slide 1 reciprocated along a line parallel to the line of tool stations, work-receivers k 1 , k 2 , k 3 , s 1 , s 2  on the slide for transferring the studblanks B between stations and for turning the blanks end-for-end between the stations 3-4 and 5-6 so as to present both ends of the blanks to the tool heads, and ejectors h 2  -h 5  and n 1 -n 4  for ejecting the blanks from the receivers into the work-holders and from the workholders back into the receivers. The toolheads q 1 , q 2  reduce or chamfer opposite ends of the blanks, the heads r 1 , r 2  preferably cutting or rolling a thread on both ends of the blanks. Stock-bars a from a magazine b are transferred to the station 1 where they are fed by rolls f against an adjustable, spring-pressed pivotedstop d and severed into blank-lengths B by a shears e. After withdrawal of the stop, the advancing bar a ejects the blank B on to a conveyer which carries it to a stop-plate at station 2 where an ejector h 1  pushes the blank into the receiver k 1 . Alternatively, preformed blanks may be ejected from a hopper by the ejector h 1 . Movement of the slide 1 transfers the blank to station 3 where it is pushed by ejector n 1  into the work-holder # 1  against a pivoted stop m 1  and clamped for the chamfering operation by tool-head q 1 . The stop m 1  is withdrawn and, during the chamfering operations, the slide 1 is returned, so that the chamfered blank may be pushed by ejector h 2  into the receiver s 1  which is mounted on a pinion t 1  engaging a stationary rack u 1 . Each of the receivers has a spring 19 applying lateral pressure to the blank. The next movement of slide 1 turns the blank end-for-end, presenting the unmachined end to the tool-head q 2 . The receiver s 2  is also mounted on a pinion t 2  engaging a rack u 2 , so that the blank is reversed between the screwing-heads r 1 , r 2 . An ejector n 5  finally ejects the stud from receiver k 3  into a receiver v where it is tested automatically by a " go " and " no-go " gauge, such that if the threads are undersize or oversize switches stop the machine and give an audible or visual warning. The next stud in succession ejects the stud from the test-receiver v into a shoot x. A variable-speed motor 11 drives the toolheads through a belt 12, chains 13, 14, gears 15, 16 and change-gears 36, 37. Feed of the heads is by cylinders 38, check-rams 39 and oil-reservoirs 40 with adjuster valves 41, permitting a quick advance followed by a slow feed and a rapid return. Limit-switches (not shown) connected in series are operated by the tool-spindles at the ends of their strokes, the spindle with the longest stroke governing the cycle-time, so that all the spindles are retracted together. The transfer slide 1 is operated by a lever 17 moved mechanically or by fluid-pressure. Brackets 21, 29 carrying the ejectors n, h, are connected by levers and links 23, 24, 31, 32 to shafts 25, 33 which are turned by cylinders 27. The machine may be controlled by a cam-shaft, or the termination of one operation may signal the commencement of the next. Workholders.-These may have an inner wall contracted on to the work by fluid-pressure produced by turning a screw-threaded plunger.