DE1157099B - One-piece, detachable steep shoulder drop center rim - Google Patents

Description

One-piece, detachable steep shoulder deep flat rim The invention relates a one-piece, detachable steep shoulder drop center rim for heavy, cast Spoked wheels.

Steep shoulder drop center rims have been developed in connection with tubeless tires for heavy trucks. They have a shoulder angle of about 151. The tire can therefore be detached from the rim more easily than with the 5 'shoulder angle of the usual tapered shoulder rim. The rim flange is extremely low, which makes it much easier to assemble and disassemble the tire. In the case of disc wheels, the bowl is welded to the drop center section. In the case of spoked wheels, a special so-called support ring must normally be welded on, which by itself must have the strength for the bracing on the clamping cone of the spokes of the wheel. If the dimensions are tight, there is a risk that the support ring will be deformed into a curved polygon according to the number of spokes.

Attempts have therefore already been made to make steel rims crimping and welding together a sheet metal cylinder with constant wall thickness, that a closed hollow profile is created between the rim shoulder and the support ring. These attempts have practically not been able to prevail to this day, except for small wall thicknesses.

Symmetrical hollow profile rims are known for bicycles and light motorcycles for wire-spoke wheels, which are either made from a flattened tube or from a Extruded profile are produced.

Asymmetrical hollow profiles on light alloy rims have not existed until today known.

The scope of the invention comprises a one-piece, detachable steep shoulder drop center rim for heavy spoked wheels, made of extruded and rounded light metal hollow profile.

It differs from the known rims in that the rim profile has an asymmetrical cavity, which consists of a conical rim bead flank, a cantilevered, conical rim foot and an inwardly curved, approximately radial web is formed.

The drawing shows an embodiment of the subject matter of the invention.

The one-sided, asymmetrical cavity 1 of the steep shoulder drop center rim is formed by a rim flange 2, a shoulder flank 3 for the tire base, a drop base flange 4, a rim base 5 and a web 6 that is concave inward, for example according to a radius 7. The rim base 5 is used for fastening the rim on a spoked wheel body, not shown, and is inclined for this purpose with a clamping cone angle 8 relative to the horizontal. The shoulder flank 3 is also inclined at a cone angle 9.

When rounding this rim from the straight, extruded bar profile, the curvature of the web 6 is increased, i. that is, the radius 7 becomes smaller. In this way, however, the foot angle 8 of the rim foot 5 and the shoulder angle 9 of the shoulder flank 3 will also decrease in accordance with the profile height 10. The resultant of the tire load during operation with the greatest load (including radial load) is shown by an arrow 11 and has almost the same direction as the web 6.

Depending on the tire base and rim base profile, there are other profiles The rim made of extruded hollow profile is possible, since it is the extrusion process allows a great variety in profile shaping, in contrast to rolled profiles, where the shaping is limited with regard to the rolling technique and profiles with cavities and undercuts cannot be made.

The rims are called removable rims on a wheel body, z. B. made of cast steel, supported and held. Such demountable rims were made z. B. executed as drop center rims and then received a Stätzring, which to the side of the center of the rim by means of a circumferential. Weld attached was. The manufacture and welding of the Stätzring are expensive operations, which is why the rims according to the invention have an advantage over the previous ones.

The advantages of the above rim design are as follows: High structural strength with low weight. Weight savings of up to 5501o are possible compared to the corresponding steel rims, while otherwise with highly stressed parts, in the best case, when converting steel to light metal, a weight saving of 40% is expected.

This in turn has the advantage of smaller unsprung masses on the Vehicle, which in turn means something secondary to the superstructures and connecting parts Weight can be saved. In addition, the driving characteristics can be improved.

There is no separately attached fastening or support ring (adapter ring) necessary. For the same reason, there is also no need for one that runs in the circumferential direction Weld.

Easier and cheaper production of the extruded profiles.

Compared to a rim made of sheet metal, there is the option of changing the wall thickness ga vary, according to the stresses occurring, what z. B. with rolled or flanged sheet metal rims with constant wall thickness is not possible. The supportive one The web of the hollow profile has approximately the direction of load on the tire Rim.

Comprehensive design options for the profile shape compared to rolled profiles.

Claims (1)

PATENTANSPRUCI-1-one-piece, removable drop center drop rim for heavy wheels, hollow profile of light metal, characterized in extruded and rounded, that the rim profile has an asymmetrical cavity (1) which consists of a conical Felgenwalstflanke (3), a projecting conical Felgenfaß ( 5) and an inwardly curved, approximately radial web (6) is formed. Documents considered: German Patent No. 672 335; Austrian Patent No. 111903; French Patent Nos. 345 645, 584 769, 558 806, 802 125, 1103 545; British Patent Nos. 19,797 from 1892, 1316 from 1907, 125 120, 584 843; Verkehr und Technik, 1955, p. 328; Iron and Steel, 1954, pp. 213-215 ; Dr.-Ing. Alfred von Zeerleder, Technologie der Leichtmetalle, 1947, p. 192.