Improvements in Machines for Milling Bolts.
Year: 1891

page_text: of Application, 8th Jan., 1891-Accepted, 14th Feb., 1891
COMPLETE SPECIFICATION.
Improvements in Machines for Milling Bolts.
I, EDWARD HOLLINGWORTH, of Dobcross, in the County of York, Power Loom
Maker, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement (which invention has been communicated to me from abroad
by George Webb, of Pawtucket, Rhode Island, one of the United States of
America, Engineer) :—
This invention relates to machines for milling bolt shanks and the underside of
bolt heads. In the finishing of bolts it is desirable that the portion of the shank
which lies between the bolt head and the screw thread should be milled or cut into
a smooth cylindrical form, and also that the under surface of the bolt head should
be trimmed off smooth and made square. Machines for this purpose are in common
use, but according to present construction each bolt (after being milled) has to be
displaced from the milling tool by the hand of the workman. My invention is
designed to remove the bolt from the milling tool by automatic mechanism com-
prising a horizontal rod placed in the revolving spindle carrying the milling tool ;
a spiral or other form of spring being employed in connection with the horizontal
rod which yields to the pressure of the bolt when inserted within the milling tool,
the arrangement being such that when the bolt has been milled and the bolt holder
withdrawn, the spring forces the horizontal rod forward in such a manner as to
eject the bolt from the milling tool, consequently the withdrawing of the bolt by
the operative is now dispensed with and a saving of time effected.
In order that my invention may be better understood, I will now make reference
to the accompanying sheet of drawings illustrative thereof, wherein Fig. 1 is a
front elevation of a bolt milling machine having my improvements applied thereto;
Fig. 2 is a sectional plan taken through the line A A¹ of Fig. 1, and Fig. 3 is an
enlarged view of certain parts of Fig. 2 except that the bolt B is shewn in the
position it occupies when undergoing the operation of milling. In the drawings
C represents the bed of the machine and D the standards or legs for supporting it ;
E is a cone pulley mounted on the hollow or tubular spindle F made to revolve in
the journals G. The forward or front end of the revolving tube F is enlarged or
made with a collar a to receive the hollow brush H held in position by set screw_b,
such hollow bush holding the milling tool I, which is secured in the said bush by
set screw c, the outer end of the said milling tool being clamped by the collar d.
On the opposite end of the frame or bed C is mounted a sliding plate J working
in dovetailed grooves formed in the bed C. A block or bracket K is secured to
the plate J by set screws e, such said plate J, together with the bracket K, being
moved backward and forward as required by means of the bell crank lever L and L¹
and link M so that on the lever L being depressed as shewn in dotted lines, the
plate J, together with the parts attached thereto, are carried forward as will be
well understood. Although the lever L is arranged to be worked by the operative,
it is evident that the said lever may be actuated by mechanical means. Upon the
sliding plate J there is also placed a block or pedestal N secured by set screws f,
such pedestal carrying a clamp O for receiving and supporting a rod or shaft P
having an enlarged end g into which is screwed a bolt holder Q made with a
socket adapted to receive the head of the bolt B.
As thus far described, the machine is similar to those in common use for milling
the shanks and heads of bolts. I will now describe the novel features of my
invention, which consists in forming the spindle F hollow and placing therein the
rod R surrounded by a spiral spring S capable of being compressed between the
collar on the shaft F and the cap T screwed onto the rear end of the hollow

page_text: shaft F.
The rod R projects beyond the cap T and is provided with a collar U
which limits the forward movement of the rod R, such said collar being adjustably
secured to the rod by set screw i. The forward end of the rod R terminates with
and forms a push pin which is capable of passing through the boss H and entering
the milling tool I.
The working of the apparatus is as follows:-When the bolt holder Q is
advanced by the movement of the bell crank lever L sufficiently far to insert the
shank of the bolt B into the milling tool I, the end of the said bolt pushes back
the pin at the end of rod R, the spring S readily yielding to the pressure of the
forward movement of the bolt; meanwhile the milling tool is revolving and cuts
the shank and head of the bolt in the usual manner, continuing to do so as long as
the tool is kept in contact therewith by the operative who is pressing down the
handle L for that purpose. When the milling has been satisfactorily done, the
lever L is raised, whereby the bolt holding mechanism is withdrawn, leaving the bolt
in the milling tool, which, however, is immediately pushed out of its position by
the push pin actuated by the spring S which is now free to act automatically. In
the accompanying drawing I have shewn the end of the bolt B to be flat; but if a
bolt having a round or tapering point is being milled, the end of the push pin k may
be cupped to receive the round or tapered end of the said bolt, whereby it will be
accurately centred ready for the action of the milling tool.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
:-
In a bolt milling machine, having means for holding and feeding the bolt, the
combination therewith of a spring-actuated rod R contained in a revolving tubular
spindle Farranged to automatically deliver the bolt from the milling tool after
completion of the milling operation, all orranged and operated in the manner
described and shewn in the drawings.
Dated this 6th day of January 1891.
TASKER & CROSSLEY,
Huddersfield and Halifax, Agents.