US2452155A - Working the die hole contour of a wire drawing die - Google Patents

Description

9 1 i w. RYBlcKI 2,452,15

WORKING THE DIE HOLE CONTOUR OF A WIRE DRAWING DIE Filed July 7, 1945 WQLEE @757 Patented o r. 26, 1948 UNITED STATES PATENT. OFFICE WORKING THE DIE HOLE CONTOUR OF A WIRE DRAWING DIE Walter Ryblckl, Garfield Heights, Ohio Application July 7, 1945, Serial No. 603,673

' 2 Claims. (Cl. 51-67) This invention relates to working the die hole contour of a wire drawing die; polishing the entrance angle, or smoothing out section, providing an example of such working; and has the advantages that it provides for repeatedly doing this work in the case of a large number of dies so as to get substantially identical results even when done by a relatively unskilled worker.

A specific example of the invention is illustrated by the accompanying drawings, in which:

Figure 1 is a front view of this exemplary machine at work on a wire drawing die;

Figure 2 is a longitudinal section of'the die showing the section of its die hole contour that is being worked and the relation of the working tool thereto as this tool is being inserted into the hole; and

Figure 3 is an end view of a detail of Figure 1, partially in cross section.

More specifically, these drawings show this illustrated machine as including means i for.

holding and rotating a wire drawing die 2 about its axis in a tilted position, a spindle 3 having an end 4 for rigidly mounting a tool 5 for working the die hole contour of the die 2, and a reciprocating surface 6 spaced opposite the face of the die 2 at an elevation holding the spindle 3 tilted when the tool 5 is mounted by the end 4 and is resting in the die hole of the die 2 and the spindle 3 is resting on the surface 6. The arrangement of these parts is such that the tool and spindle have a common axis which is aligned with the die hole axis, while the surface 8 frictionally restrains the spindle against rotatingwith the die while providing the spindle with africtional reciprocating drive.

The die 2 is a tungsten carbide die of the usual type having a steel case mounting the tungsten carbide nib in which the die hole is formed, and having a cylindrical exterior concentric with the die hole axis. The means i is a releasable chuck of the self-centering type familiar to machinists and mounted by one end of a rotative shaft 1 journaled by a tilting frame 8 provided with means 9' for adjusting and fixing its degree of tilt, this means 9 being of any suitable form and thus making it unnecessary to describe the one specifically shown. The surface 6 comprises a length of flexible material in bent around a wheel I I rotatively journaled by the frame 8 at right angles to the shaft 1, one end of this length l0 being connected with a rotative crank arm l2 and its other end being tensioned by spring means l3. Leather provides a good example of the material from which the length it may be mum pressure of the tool on the die hole contour against which it is working, is either too light or too heavy. With this understood it is now appropriate to describe the operation of the machine.

A die to be polished is placed in the chuck I and the latter tightened, this automatically centering the die hole axis relative the rotative axis of the shaft 1. This shaft I may then be rotatively powered, as by applying belt power to the pulley l4 shown on its other end from that mounting the chuck l. The rotative speed may be in the order of that commonly used in the case-of the manual method. At this time, rotation of the crank arm l2 causes reciprocation of the surface 6, the crank arm 12 being shown as provided with a rotative crank shaft i5 having a pulley IS on its end remote from the crank arm l2 and rotatively driven by a belt powered by a pulley l1 fixed on the shaft 1 right next the pulley I4 and so driven by the latter. The crank arm 12 is shown as having an adjustable throw, any arrangement effecting this being suitable and it being therefore unnecessary to specifically describe the one shown, and this arm should be adjusted so that the reciprocating stroke of the surface 6 is appropriate to work the entrance angle, or smoothing out section, of the die hole contour with the tool 5. Now, with the die rotating and the surface 6 reciprocating, the reciprocating direction of course being axially of the die hole of the die, and asuming that the spindle 3 has the tool 5 fixed in its chuck 4, the next step is to apply the abrasive, insert the end of the tool 5 lightly into the die "hole and lay the spindle tangentially onto the surface 6, the surface 6 frictionally supporting and reciprocating the spindle 3 so that the latter reciprocates the tool 5 in the die hole and polishes its contour, this surface also frictionally restraining rotation of the spindle and hence-of the tool, at this time. The pulley H is provided with flanges Ila, both for the purpose of providing lateral stability for the spindle 3 and to keep the length iii in position,

3 it therefore being convenient to rest the spindle 3 on the surface as described. Further security may be obtained by means of the illustrated releasable clip la. The spindle is unsupported vertically, excepting that it fulcrums on the surface 6 with its tool resting on the die hole contour because of the weight of the spindle, chuck and tool and the tilt of the parts.

It can be seen that the above involves a new method of polishing the contour of a wire drawing die which may be carried out manually or by machines other than the one specifically disclosed here. This method includes holding the wire drawing die in a tilted position with a tool resting in its die hole and held by a tilted spindle fulcrumed remotely from the die, the fulcrum being on the surface 8 in the case of the illustrated machine as has been described, and with the spindle otherwise free from vertical support, while causing relative rotation and reciprocation between the die and the tool.

The foregoing has the great advantage that the maximum pressure that can be exerted by the tool against the die hole contour has a positive constant value fixed by the weight of the spindle 3, the chuck 4 and, while relatively inconsiderable, the weight of the tool 5, and by the tilt of the die and the spindle. In the case of the illustrated machine, if the frame 8 is given the proper tilt, and the spindle, chuck and tool the proper weight, all to provide the proper maximum working pressure of the tool 5 against the die hole contour, then this pressure remains constant regardless of the number of dies that may be polished.

Since the tilt of the parts is primarily needed to assure a forward feeding tendency and prevent the tool from falling out of the die hole by working backwardly more than forwardlyas it is reciprocated by the spindle 3 resting on the reciprocating surface 6, and since it has comparatively little effect on the tool working pressure as compared to the weight of the spindle, it maybe preferable to provide a fixed tilt to the frame 8 and to dispense with the adjustable means 9, since this prevents tampering by the worker. If the worker is given the spindle 3 with its chuck 4 and the tool 5, all having a total weight appropriate for the size of the die and the particular operation being carried out, then there is no chance for any serious mistakes. If the adjustable crank arm i2 is set so that the stroke of the reciprocating surface 6 is too great, this is immediately detectable because the tool falls out of the die hole, and if the stroke is too short proper polishing is not effected. However, it may also be desirable to fix the throw of the crank arm positively to prevent its being tampered with.

' The spindle 3 is illustrated as having a square cross section to enhance its resistance to rotation afforded by its resting frictionally on the surface Hi. In many instances, it may be more desirable to give this spindlea circular cross section so that while it is frictionally restrained by the surface it! against rotation, it can more easily turn against this restraint if the tool receives excessive torque, or so it may turn slightly at each forward reciprocation to provide for distribution of the abrasive polishing paste. Other shapes may be given it, as required.

I claim:

1. A machine including means for holding and rotating a wire drawing die about its axis in a tilted position, a spindle having an end for mounting a tool for working the die hole contour of said die, and a reciprocating surface spaced opposite the face of said die at .an elevation holding said spindle tilted when said tool is mounted by said end and is resting in said die hole and said spindle is resting on said surface, said means comprising a rotative shaft mounting a chuck on one end for releasably holding said die and journaled by a tilting frame provided with means for fixing its degree of tilt, and said surface comprising a length of flexible material bent around a wheel rotatively journaled by said frame at right angles to said shaft with one end of said length connected with a rotative crank arm and its other end tensioned by spring means, said wheel being positioned so that when said spindle is resting tangentially on said length bent therearound said spindle is held as described.

2. A machine including means for holding and rotating a wire drawing die about its axis in a tilted position, a spindle having an end for mounting a tool for working the die hole contour of said die, a reciprocating surface spaced opposite the face of said die at an elevation holding said spindle tilted when said tool is mounted by said end and is resting in said die hole and said spindle is resting on said surface, said surface comprising a length of flexible material bent around a wheel rotatively journaled by said frame at right angles to said spindle, and means for reciprocating said length of flexible material, said wheel being positioned so that when said spindle is resting tangentially on said length bent therearound said spindle is held as described.

WALTER RY'BICKI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 911,210 Conradson Feb. 2, 1909 FOREIGN PATENTS Number Country Date 527,000 Germany June 12, 1931

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