US 2133091 A
Description (OCR text may contain errors)
Oct. 11, 1938. J. H. GETTIG 2,133,091
AXLE AND METHOD OF FORMING SAME Filed Oct. '7, 1936 IIIIIIIIIII 'IIIIII/ fa 2 E Patented Oct. 11, 1938 AXLE AND METHOD OF FORMING SAltIE Joseph H. Gettig, Buchanan, Mich., assignor to lark Equipment Company, Buchanan, Mich., a corporation of Michigan Application October '7,
This invention relates to axles, and more particularly is directed to the construction of axles for use in trailers and the like where no driving means is provided but the wheel is journaled for rotation directly on the axle.
It has heretofore been the practice to-construct such axles from solid structural members, or from hollow members having theends coined or suitably forged to produce the bearing seats for the hub of the wheel.
The present invention proposes to form the axle from a piece of tubing such as a seamless tube or a tube formed by rolling up and welding a flat sheet of stock, and contemplates especially the 1 formation of the axle ends in such manner as to prevent defects such as cracking, fractures or the like which have been one of the main disadvantages of axles previously produced.
One object of the present invention is to provide for reduction of the ends of the tubular axle member in such manner as to prevent any folds, cracking or faulting of the end section of the axle so that a section of uniform strength and rigidity is produced.
Another object of the present invention is to provide for inserting a mandrel or centering member within the end of the axle tube after initial reduction and prior to its being swaged to complete form whereby the internal surface of the axle end embraces this mandrel-like member upon completion of the swaging operation.
Other objects and advantages of the present invention will appear more fully from the following detailed description which, taken in con- 35 junction with the accompanying drawing, will disclose to those skilled in the art the particular method of forming the axle constituting the present invention.
In the drawing:
Figure 1 is a sectional view through the axle blank prior to the formation of the axle;
Figure 2 shows the first step in the forming operation, being partly in section;
Figure 3 is a corresponding view illustrating the axle after the second operation on the blank;
Figure 4 is a corresponding view showing the finished axle; and
Figure 5 is an end section view showing the defects occurring in prior methods of forming this type of an axle.
Referring now in detail to the drawing, the blank 5 of Figure 1 may be a seamless tube, or may be a piece of flat stock rolled into tubular form and then longitudinally welded along the abutting edges. The blank 5 preferably has an 1936, Serial No. 104,428
initial wall thickness as indicated by the wall 8, and is of a length slightly less than the desired length of the finished axle.
The first step in forming the axle of the present invention is to reduce the end sections theremade.
Simultaneously with this reduction the end portion of the axle is increased in wall thickness and elongated.
- After the reduction is effected at opposite ends of the housing, and before the ends are completely closed, a rod or mandrel-like member 8 is inserted into each end of the axle, and is held in centered position therein in any suitable manner.
The rod 8 may be of steel, iron, or any equivalent material, but preferably should be of relatively cheap material inasmuch as it serves no purpose so far as load support or wear is concerned.
After the rod has been placed in position, each end of the axle is subjected to further reduction while the rod 8 remains in place.
As the swaging is completed, the thickened reinforced end 8 of the axle encloses and completely embraces the rod 8, holding the same in fixed position and also thereby preventing any folding, lapping or cracking of the axle or shaft.
Such defects are undesirable and may be of serious nature, especially if the axle is to be heat treated.
The swaging operations for reducing the diameter of the axle ends may be accomplished by endwise swaging which, in turn, will produce slight elongation of the axle so that the finished axle will be of the required length, it being re membered that the blank is slightly shorter than the axle length required to accommodate this elongation. As shown in Figure 4, the reduced end portion 8 of the axle which encloses and embraces the rod 8 is joined by the frusto-conical portion II! to the rear portion 1 of the initially reduced cylindrical end of the axle. The swaging operation also produces a considerable thickening of the walls of the axle at the same time that elongation is produced, thus providing a thickened reinforced end for the axle which is then subsequently machined on the surfaces 1 the wheel hub.
The provision of the rod 8 in the end of the axle prevents the formation of fissures, cracks or folding within the end of the axle as is indicated in Figure at l2, where such defects are formed due to the fact that the axle is reduced to produce a solid end and consequently, the internal surface of the end of the blank is folded and lapped during this reduction, producing the fissures which are especially undesirable if the axle is to be subsequently heat treated.
It will therefore be apparent that I have provided a novel process for forming what is known as a dead type of axle in which the wheels are mounted for free rotation at opposite ends of the axle on bearing seats formed by the reduction of these ends, with the consequent thickening of the walls thereof.
I do not intend to be limited to the exact details shown and described in connection with the illustrated embodiment of the present invention, as the particular process employed may equally well be employed for other types of shafting for uses other than as axles or the like. The invention is therefore to be limited only as defined by the scope and spirit of the appended claims.
1. The method of forming an axle from a tubular blank which comprises initially reducing the opposite ends of the blank to form end portions of hollow cylindrical section and of increased wall thickness and having frusto-conical portions between said ends and the remainder of the blank, inserting solid mandrel-like members in the reduced ends of said blank, subsequently reswaging said frusto-conical section to form an intermediate cylindrical bearing seat spaced from said first reduced portion by a frusto-conical section with said first reduced portion being further reduced in such manner as to rigidly embrace and enclose said member to thereby close the end of the axle xially.
2. An axle comprising a tubular blank having reduced thickened end portions rigidly embracing solid mandrel-like members closing the interior of said axle and having external bearing seat portions of different diameters spaced axially by a frusto-conical section at each of the reduced ends thereof, said members preventing fracturing of the internal portions of said ends.
3. In the manufacture of a dead axle from a tubular blank, the method of forming the axle end which comprises initially reducing the end of said blank to form a thickened portion joined to the remainder of the blank by a frusto-conical section, inserting a solid cylindrical mandrel of smaller diameter than the internal diameter of said reduced end into said end with the inner end of said mandrel adjacent said frusto-conicalsection, and reswaging a substantial portion of, said reduced end to engage about and lock said mandrel therein, and to produce a second frusto-conical section intermediate said reswaged portion and the remaining length of said initially swaged portion. r
4. In the manufacture of axles from tubular blanks, the method of producing a solid end free from fissures and cracks and capable of rotatably supporting a wheel thereon which comprises initially swaging the end of said blank to reduce its-diameter and increase its wall thickness, inserting a solid mandrel into said end, and reswaging a major portion of said end to flow the interior surface thereof into gripping engagement with said mandrel, and to form annular bearing seat portions of different diameters separated by a frusto-conical section, said mandrel preventing collapse'of the internal surface of said end during-said reswaging whereby folding or cracking of said surface is prevented.
JOSEPH H. GETTIG.