US3461471A - Method of forming lock washers by rolling multiple sections from a single rod - Google Patents

Description

2 Sheets-Sheet 1 INV ENTOR CHARLES N. MELLOWES ATTORNEYS 9, 1969 c. N. MELLOWES METHOD OF FORMING LOCK WASHERS BY ROLLING MULTIPLE SECTIONS FROM A SINGLE ROD Filed April 5, 1967 NM 3% i W o7 no Q9 1 ill w m a a 0. 09 iv Q Filed April 3, 1967 Aug. 19, 1969 c. N. MELLOWES 3,

METHOD OF FORMING LOCK WASHERS BY R MULTIPLE 2 sheets-shed 2 NNNNNN OR M ELLO United States Patent 3,461,471 METHOD OF FORMING LOCK WASHERS BY ROLL- IN G MULTIPLE SECTIONS FROM A SINGLE ROD Charles N. Mellowes, 9560 N. Lake Drive, Milwaukee, Wis. 53217 Filed Apr. 3, 1967, Ser. No. 627,810 Int. Cl. B21d 53/20; B23p 17/00 US. Cl. 10-86 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field of the invention.The present invention pertains to the manufacture of lock washers on machines in which the wire, of predetermined cross-section, is continuously coiled in helical form, and in which the lock washers are cut off from the helical coil one after another.

Description of the prior art.In the manufacture of small size lock washers such as A medium, A medium, and A" medium, it is at present necessary to purchase from a wire mill fully processed, cleaned, and annealed wire in the proper diameter. It has not heretofore been practical for the washer manufacturer to purchase hot-rolled rod from a steel mill and to draw the rod himself to proper size. The reason for this is that the smallest diameter in which hot-rolled rod can usually be purchased is To draw this rod into the relatively small size wire required for manufacturing A medium, medium, and medium lock washers would require so many drawing operations that the wire would become too brittle to be coiled into a washer.

SUMMARY OF THE INVENTION The present invention provides an improved method wherein small size lock washers such as A" medium, medium, and medium lock washers can be manufactured successfully from hot-rolled rod, thereby effecting substantial savings in cost over methods wherein annealed and fully processed wire in proper specifications must be purchasedfrom a wire company. The invention includes the steps of drawing the hot-rolled rod to a smaller diameter, but to a diameter which is much larger than that required for the product to avoid too much cold working, the flattening of the reduced diameter rod, the rolling of the flattened rod to multiple cross-sections, such as to a double keystone cross-section, the separating of the multiple sections from one another, and the feeding of the separated strands of wire after separation into a plurality of lock washer manufacturing machines. By forming multiple cross-sections from the single rod with separation occurring thereafter, the proper size for the relatively small lock washers may be obtained.

An object of the invention, therefore, is to provide a method of manufacturing small size lock washer-s from oversize hot-rolled rod, as above described, which eliminates the necessity of excessive cold working of the rod stock.

A further object of the invention is to provide a method as above describedwhich may be carried out continu- ICC ously so that the rod stock has no opportunity to ageharden between the various procedures.

A further object of the invention is to provide an improved method as above described whereby a substantial saving in cost may be effected, which method makes it unnecessary for the washer manufacturer to stock assorted quantities of annealed wire of proper diameters and specification for the various small size washers desired.

With the above and other objects in View, the invention consists of the improved method of forming lock washers by rolling multiple sections from a single rod, and all of the steps and procedures as set forth in the claims, and all equivalents thereof.

BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawing, in which the same reference numerals designate the same parts in all of the views:

FIG. 1 is a side elevational view, partially diagrammatic, showing preferred equipment used in the continuous process, parts being shown in vertical section;

FIG. 2 is a cross-section through the hot-rolled rod from which the lock washers are formed;

FIG. 3 is a cross-sectional view through the rod after the first drawing operation;

FIG. 4 is a cross-sectional view through the rod after a second drawing operation;

FIG. 5 is a cross-sectional view after the stock has been flattened;

FIG. 6 is a cross-sectional view showing the stock after it has been rolled into a double keystone crosssection;

FIG. 7 is a cross-sectional view showing the separated portions of the stock;

FIG. 8 is a fragmentary enlarged side elevational View of the coiler and cutter;

FIG. 9 is a fragmentary plan view looking down on the coiling mechanism;

FIG. 10 is a longitudinal sectional view through the shaping rolls; and

FIG. 11 is a similar view through the parting rolls.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly to the drawings, the hotrolled rod 10, such as the minimum size obtainable from a steel mill, is fed from any suitable source such as a rotatable stand 9. This rod has not been previously annealed or cleaned. It is first fed to a mechanical descaler 11 of any known structure, usually consisting of pulleys 12, 13, 14, 15 and 16 which cause the rod to make a plurality of right-angular bends, usually in four planes, the bending acting to crack off the scales.

Thereafter the descaled rod is subjected to one or'two drawing operations, one after another. If it were attempted to draw the rod stock down to a wire size having proper diameter for forming A medium, medium, or medium lock washers, for example, there is too much cold working, with the result that the wire is too brittle to be coiled successfully. In FIG. 1, the first drawing die is designated by the numeral 17. This performs the first reduction in diameter of the rod, to for example. The wire is pulled through the first drawing die by power roll 18 suitably driven from an electric motor 19. The wire passes' from the power roll'18 underneath the dancer roll 20 mounted on the free end of levers 21 swingable on a pivot 22. The dancer roll is suitably associated with a rheostat 23 so that as the roll moves up or down it serves to advance or retard the rheostat. As the drawing die 17 wears from continued use the diameter of the drawn wire gradually increases. When this occurs the dancer roll moves up slightly. During such movement it acts on the rheostat 23 to slow down the motor 19. Movement of the dancer roll in the opposite direction will speed up the motor automatically. From the dancer roll 20 the wire passes over another guiding roll 25 and then through a second drawing die 26, if a second reduction is needed, which further decreases the diameter of the wire, to for example. Pulling the wire through the drawing die 26 is a power roll 27 driven by an electric motor 28, there being another dancer roll 29 operating a rheostat 30 in circuit 31 to the motor 28. The wire from the dancer roll 29 passes over another guide roll 32 and then through flattening rolls 33 and 34. The wire may then be pulled by a power roll 35 driven by an electric motor 36. Dancer roll 37 operates a rheostat 38 in the circuit 39 to the electric motor 36 to control the speed of the power roll 35. Any enlargement of the rod due to wear in a proceeding, drawing or forming operation is compensated for in the next section of the machine by the action of the dancer roll associated with said next section of the machine by the action of the dancer roll associated with said next section.

As the rod emerges from the flattening rolls 33 and 34 it has the flattened cross-sectional shape shown in FIG. 5 and designated 10a.

The flattened cross-section stock ltla is then fed between closed pass rolls 40 and 41. The roll 40 has a circumferential recess with the cross-sectional shape shown at 42 in FIG. 10 and the roll 41 has a coacting circumferential projection shown at 43 in FIG. 10. Thus when the flattened stock passes through the shaping rolls 40 and 41 it is given multiple cross-sectional shape such as the shape of a double keystone in cross-section shown in FIG. 6, one of these sections being designated 10b and the other one 100. If desired the cross-sectional shape .may include more than two keystones or other required shapes. It is to be noted that the keystone portion 10b is offset upwardly from the section 100 to facilitate parting. Thereafter the stock with the double keystone cross-section passes through any suitable instrumentality for separating the portions 10b and 100. This is preferably accomplished by parting rolls 44 and 45. The parting roll 44 has the circumferential recess shown at 46 in FIG. 11 and the parting roll has the cross-sectional shape shown at 47 in FIG. 11. These rolls act to exert a gradual shearing force on the wire to cause the two sections to part as shown in FIG. 7. Each of the keystone cross-sections of wire of FIG. 7 is then passed as a separate strand to a separate lock washer forming machine such as the machine 48 for the strand 10b, and 49 for the strand 100, each strand being twisted before it enters the machine so that the keystone cross-section is disposed as shown in FIG. 11. Inasmuch as the machines 48 and 49 are identical, only one will be described and the same numerals primed will be used on the other machine. The wire leaving the parting rolls is passed between a set of intermittently driven feed rolls 50 and fed to a coiler and cutter 51. The feed rolls oper ate intermittently and turn in one direction only. They feed the wire between the coiling rolls 52 and 53 (FIG. 8) so that the wire is caused to be coiled around the roll 52. The large dimension 54 of the keystone crosssection faces outwardly as the wire is fed to the coiler, and the action of the coiler is such as to narrow the dimension at 54 during coiling so that a rectangular crosssection results.

The roll 52 has a cutout portion 55 with the wall 56 forming a shearing surface to coact with a knife 57. During the time that the feed rolls 50 are in the act of feeding, the cutter 57 is in a raised position. Just before the knife 57 performs its cutting action the feed rolls stop momentarily. After each cutting stroke, a washer W falls into a suitable receptacle 58. As soon as a batch of washers is accumulated in the receptacle the washers are promptly fed into a heat treating furnace 59. This serves to give the finished washers the necessary spring temper needed in this type of product.

From the above it is apparent that the method is a continuous operation, with the rolled rod 10 passing from one operation to another without intermission. Thus there is never any opportunity for age-hardening of the material prior to completion of the washers and prior to treatment in the heat treating furnace 59, it being noted that the period for collection of washers in the containers 58 and 58' is relatively short so that the washers are promptly fed into the tempering furnace 59.

Thus because of the novel continuous process, rolled oversize rod material, instead of expensive, annealed wire sized to specification, may be used for producing relatively small size lock washers. Heretofore, before a washer manufacturer received annealed wire from a wire mill, the rolled rod from the steel mill had to be heat treated and cooled in air to give it the necessary crystalilne struc ture for wire drawing; it had to be cleaned and lime coated; it had to be drawn to a particular specification; it had to be annealed to provide proper ductility; and the annealing had to be followed by another cleaning and lime coating process. Between each one of these procedures there was handling and oftentimes transportation of the material from one station or location to another with delays before further processing. All of this adds to the expense of the annealed wire product.

With the present process the hot-rolled rod can be purchased in the minimum size and stored for any reasonable length of time. When fed through the continuous process there is no intermission, and the wire is quickly put through the descaling, the drawing operations, the rolling operations, and the coiling, one step after another, followed by prompt tempering. With the novel concept of only partially reducing the size of the hotrolled rod, to avoid too much cold working, followed by the rolling of the reduced diameter rod into multiple sections which are subsequently parted, it is practical to use hot-rolled rod for forming small size lock washers, and the problem of too many drawing operations to obtain a small enough diameter is eliminated. In addition, with the improved process, all of the handling which is customarily required in a wire mill between the various stages of wire processing is eliminated, and the cold working in the drawing dies, together with the final tempering in the tempering furnace 31, function to take the place of all the treatments which were previously performed in the wire mill, the washers being set into final tempered condition before age-hardening has had an opportunity to take place. With the present process, at any given point on the rod being fed from the supply, the time from start to finish of the entire process is from ten to twenty seconds. In the conventional procedure it may require from several days to possibly weeks to prepare hot-rolled rod, as each process is done separately and in dilierent departments of the wire mill. With the present invention it is the continuous motion through all of the steps of the process, consuming only a few seconds in time, which keeps the rod ductile enough to undergo its complete transformation from rolled rod to lock washer without the need for the usual processing of the rod in the wire mill as heretofore described.

What I claim is:

l. A method of manufacturing relatively small size lock washers from oversize hot-rolled rod in which the improvement comprises the steps of reducing the diameter of the rod, shaping the rod to flatten and to produce multiple cross-sectional shapes joined to one another and each sized and shaped to produce a washer, separating the joined sections one from another to produce separate strands, and manufacturing lock washers from each separated strand.

2. A method as set forth in claim 1 which includes the step of flattening the rod prior to rolling it into the multiple cross-sectional shape.

3. A method as set forth in claim 1 in which the multiple sections comprise keystone shapes in cross section, each suitable for producing washers by a coiling process.

4. A method as set forth in claim 1 in which the rod is rolled into the shape of two keystone cross sections connected at their minor dimension.

5. The method as set forth in claim 4 in which the two keystone cross-sectional shapes are offset from one another to facilitate separation.

6 References Cited UNITED STATES PATENTS JOHN F. CAMPBELL, Primary Examiner 10 D. C. REILEY, Assistant Examiner U.S. Cl. X.R.

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