Method of manufacturing solid ring wheel rims

Abstract

A solid forged cylindrical ring with no welds is machined to form a cycle wheel rim for a spoked wheel. Holes are drilled in the inner perimeter of the rim to receive spokes from the hub. This process can produce rims used an many other forms of wheel assemblies.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of making wheel rims and particularly to a method of making a rim for a spoked motorcycle racing wheel from a forged aluminum ring that is machined to shape the rim and drilled to form holes for spokes which attach the rim to the hub, thereby creating a sturdy and lightweight one-piece solid wheel rim.

2. Description of the Prior Art

Motorcycle racing wheels generally comprise a central cylindrical hub that centrally anchors a plurality of spokes or other wheel supporting elements attached to a circularly peripheral rim that ultimately supports a tire thereabout.

Motorcycle wheels rims were typically formed by running sheet stock through rolling machines to roll metal strips and then forming those strips into a hoop and butt welding the two ends together, thereby forming the rim. Most rims were rolled from flat steel strips into shapes (profiles) that holds rubber tires round for use on cycles and anything else. These steel rings were generally “Flash” butt welded together. This was used for a percentage of motorcycles since the beginning of cycles. These particular rims use spokes to keep them concentrically rotating about the bearing held in place with a hub and an axle.

Then, Aluminum became more popular on cycles because it had almost the same strength as the steel used to make rims and the Aluminum only weighed about ⅓ as much as steel. This made companies and others to start making rims from Aluminum. Lower weight wheels make a cycle ride nicer and turn easier plus the suspension has less “unsprung weight” to deal with. This improves the way suspension components work.

Making an Aluminum rim usually starts with extruding an Aluminum shaped piece of material to a long length and then pulling it straight for a little bit to straighten it more. This extruded shape is often made to the final (net) size wanted on the final product. These extrusions are needed in all of the different widths wanted to be produced. The Aluminum is heat treated many different ways and the material has different properties depending on the heat treatment or none at all.

These Aluminum extruded shapes are then rolled into coils similar to a large spring. They could even be rolled individually if cut to accurate lengths. These coils can be cut to lengths that will allow the circular ring segment to be twisted flat and welded together.

Welding aluminum together is different for most of the alloys of Aluminum but using a method called Flash Butt welding allows the weld to be close to the material's strength without needing necessary further heat treatment. The weld does produce a small amount of material to be at the wrong temperature too long and these sections on each side of the weld loose some of the properties or strength once established in the material. The Flash Butt welding compresses the Aluminum while it is being heated by the Flash Butt weld so the properties of the Aluminum are mostly maintained. The areas with some decline in properties is called the Heat Affected Zone (HAZ).

By compressing the material as it melts together, the length is shortened. This makes a round ring before welding look tear drop shaped. This shape needs to be bent or compressed (or expanded) into a true circle again. The extra material squished out because of the welding process needs to be removed to the original profile of the rim shape. Once again, after doing this, the rims can be compressed or stretched to a true dimensional circle with other processing equipment. The equipment, rollers, welders, etc. needed to make rims this way is very expensive and difficult to operate.

Some custom cycle wheels and truck wheels are currently made from solid chunks of forged wheel blanks, but they are the entire wheel including the hub and rim as well as the connectors between the hub and rim.

A variety of prior art patents deal with wheel fabrication, but none indicate a method for forming a rim from a forged ring.

U.S. Pat. No. 4,589,177, issued May 20, 1986 to Secolo, is for a method of manufacturing a wheel rim for a motor vehicle, including cutting off a section of an extruded cylindrical tube to produce a hollow cylindrical rim blank, and subjecting the blank to two successive deformation steps. During the first step, only the central section of the blank is deformed radially inwardly, the diameter of the end sections remaining substantially unchanged. In the second step, only the edge portions of each end section are deformed radially outwardly, so that the region between each edge portion and the central section is unchanged in diameter. Also, the outermost part of each edge of the blank is bent into a U-shape. The rim is then gauged to finish it. The first deformation step is performed by a pair of cooperating rollers having central sections shaped to deform the central section of the blank. The end sections of the rollers are spaced apart to accommodate the end sections of the blank, the spaces being open at the sides of the rollers to permit free endwise flow of the rim blank outwardly from between the rollers.

U.S. Pat. No. 6,219,918, issued Apr. 24, 2001 to Wieland, provides a method of finish machining a spoked wheel rim. A spoked wheel rim is provided having a hub defining an axis, a plurality of spokes projecting radially from the hub, and a rim ring attached to outer ends of the spokes is machined by first mounting it in a loading/unloading station into a holder rotatable about a holder axis with the rim axis generally coaxial with the holder axis. Then the holder is orbited by a turntable carrying the holder from the loading/unloading station into a working station angularly offset relative to the loading/unloading station about a turntable axis between the stations. A rotating tool is then displaced by means of a head carried on a hexapod positioner at least over surfaces of the spokes while holding the rim stationary in the working station to machine the surfaces. The rim is then continuously rotated about the holder axis in the working station while engaging a rotating tool carried on the hexapod positioner with an edge of the rim ring to machine the edge.

U.S. Pat. No. 3,364,550, issued Jan. 23, 1968 to Jessee et al., shows a method of forming tire rims having a drop-center. A flat strip is bent into a hoop and welded together at the ends. The hoop is reshaped by a series of steps including die pressing and/or rolling steps which form the bead seats, flanges, and drop-center.

U.S. Pat. No. 6,666,525, issued Dec. 23, 2003 to Schroepfer, is for a spoked wheel apparatus that is symmetrical, is reversible, employs spokes that are threaded on both ends, and is capable of supporting a tubeless tire, without air leaking from the tire. A hub assembly for the wheel apparatus includes two sides, and each side includes a plurality of alternately crossing spokes that are connected between the hub assembly and a wheel rim portion. Each hub side includes an interchangeable and reversible drive dowel assembly capable of receiving a drive sprocket or disc brake. For a hub side, some spokes are connected between outer portions of the hub side to the wheel rim portion, and some spokes are connected between inner portions of the hub side to the wheel rim portion. Alternating pairs of inner and outer spokes come into interference contact midway between the hub assembly and the wheel rim portion, whereby strengthening and stabilizing effects are provided between the interfering spokes.

U.S. Patent Application #20040025977, published Feb. 12, 2004 by Schroepfer, indicates a wheel rim production method that includes the steps of obtaining a length of extruded heat treatable metal alloy, preferably aluminum alloy, that has a cross-section of a wheel rim; heat treating the length of heat treatable metal alloy; winding or otherwise shaping the heat-treated length of metal alloy into a ring, leaving free ends in the ring forming a ring gap between the free ends; preparing the free ends of the ring for providing mating surfaces for welding; welding the mating surfaces of the ring, preferably using electron beam welding, to form a completed wheel rim; and finishing the completed wheel rim to achieve desired wheel rim parameters. In accordance additional aspects of the invention, additional steps can be carried out prior to obtaining a length of extruded heat treatable metal alloy that has a cross-section of a wheel rim.

What is needed is a simplified method of forming a variety of sizes and shapes of rims for spoked wheels that does not require special tooling or machines and can shape a rim from a solid ring.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a simplified method of forming a variety of sizes and shapes of rims for spoked wheels that does not require special tooling or machines and can shape a rim from a solid ring.

A corollary object of the present invention is to provide a method of making a high strength rim by using conventional shop equipment to machine a solid cylindrical ring into a rim.

Another object of the present invention is to provide a method for fabricating a solid rim of high strength material with no welds in it to weaken the material.

In brief, a solid rim (with no welds) of high strength and preferably light weight material for a spoked motorcycle racing wheel or any of a variety of sizes and shapes of wheel rims is formed by a method of manufacturing the rim preferably from a forged aluminum cylindrical ring or a solid cylindrical ring produced by other means that is machined using conventional shop equipment, shaping the rim from the solid ring and drilling holes in the rim to produce passageways for spokes which attach the rim to the hub, thereby creating a sturdy and lightweight wheel rim.

An advantage of the present invention is that it provides a simplified method of forming a variety of sizes and shapes of rims for spoked wheels that does not require special tooling or machines and can shape a rim from a solid ring.

A further advantage of the present invention is that it provides a method of making a high strength rim by using conventional shop equipment to machine a solid cylindrical ring into a rim.

Another advantage of the present invention is that it provides a method for fabricating a solid rim of high strength material with no welds in it to weaken the material.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other details of my invention will be described in connection with the accompanying drawings, which are furnished only by way of illustration and not in limitation of the invention, and in which drawings:

FIG. 1 is a perspective view of a cylindrical ring of high strength material formed in the first step of the method of the present invention;

FIG. 2 is a perspective view of a rim formed in the second step of the method of the present invention by machining the cylindrical ring of FIG. 1;

FIG. 3 is a perspective view of the rim of FIG. 2 with the holes for the spokes formed in the third step of the method of the present invention by drilling the rim of FIG. 2.

BEST MODE FOR CARRYING OUT THE INVENTION

In FIGS. 1-3, a method of making a wheel rim for a spoked vehicular wheel comprises a first step of forming a solid cylindrical ring 21A from a high strength material, as shown in FIG. 1, a second step of machining the cylindrical ring to shape the cylindrical ring into a vehicular wheel rim 21B, as shown in FIG. 2, the rim configured to support a vehicular tire around an outside perimeter of the rim, and a third step of drilling a series of holes 25 around an inner perimeter 24 of the rim, as shown in FIG. 3, to receive a series of spokes from a wheel hub in the series of holes or, attaching spoke material(s) to the hub and rim in mechanically safe ways such as brazing, rivets, welding, pinning etc.

The first step comprises forming a solid one-piece non-welded cylindrical ring 21A by forging, hot stamping, hot rolling, or hammering a solid block of high strength material into a cylindrical ring or casting a molten high strength material into a cylindrical ring, or extruding a high strength material into a pipe and cutting the pipe into cylindrical rings.

The second step comprises making a finished rim 21B, in FIG. 2, from the cylindrical ring by at least one process taken from the list of processes including working the ring on a CNC lathe, milling the ring on a CNC milling machine, working the ring on a manual lathe, and cutting the ring with a knife or any other object.

The cylindrical ring may be formed from a block of material taken from a list of materials including aluminum, Titanium, steel, plastic, and any other structurally rigid material which can be forged or produced accurately and strongly.

The vehicle wheel rim is a wheel rim taken from the list of wheel rims including a cycle wheel rim, a cart wheel rim, a car wheel rim, and any moving wheeled conveyance wheel rim.

Preferably, the rims are aluminum cycle rims turned from forged rings.

The first step may comprise using contoured rollers to roll forged high strength material into a ring close to an actual desired rim size.

A forging machine called a ring roller may be used in the first step to form the cylindrical ring. The ring is preferably made from a piece of aluminum round bar stock. Any aluminum can be used along with other metals or materials. A piece of aluminum is cut off the round bar and heated. The hot piece has a hole pierced through it so a steel mandrel from the rolling machine can pass through it. The rolling machine presses two other rollers (parallel to the first mandrel) against the hot aluminum material and starts to compress it against the mandrel. As the pressing (both rollers) happens the mandrel rotates, this causes the hot aluminum to get squeezed thinner and elongate under compression. Compression (elongation) makes the hot stock (material) go into a larger arc. As this continues, the hot material keeps rotating and finally makes a larger circle with a thinner wall. The height can even be controlled by some rolling machines with a tapered roller.

Forging companies make these rings for aerospace, power plants and other industries. The process is called forging. There are no welds in the ring. The material is worked in a hot condition. These rings allow turning the ring forging into rims that conform to rim standards or according to any profile (shape). This rim process provides the ability to make any size or shape rim (thickness, widths etc.).

It is understood that the preceding description is given merely by way of illustration and not in limitation of the invention and that various modifications may be made thereto without departing from the spirit of the invention as claimed.

Claims

1. A method of making a wheel rim for a spoked vehicular wheel, the method comprising:

a first step of forming a solid non-welded cylindrical ring from a high strength material;

a second step of machining the cylindrical ring to shape the cylindrical ring into a vehicular wheel rim configured to support a vehicular tire around an outside perimeter of the rim;

and a third step of drilling a series of holes around an inner perimeter of the rim to receive a series of spokes from a wheel hub in the series of holes.

2. The method of claim 1 wherein the first step comprises forging a solid block of high strength material into a ring.

3. The method of claim 1 wherein the first step comprises hot stamping a solid block of high strength material into a ring.

4. The method of claim 1 wherein the first step comprises hot rolling a solid block of high strength material into a ring.

5. The method of claim 1 wherein the first step comprises hammering a solid block of hot high strength material into a ring.

6. The method of claim 1 wherein the first step comprises casting a molten high strength material into a solid ring.

7. The method of claim 1 wherein the first step comprises extruding a high strength material into a pipe cut into a series of rings.

8. The method of claim 1 wherein the second step comprises making a finished rim from the cylindrical ring by at least one process taken from the list of processes including working the ring on a CNC lathe, milling the ring on a CNC milling machine, working the ring on a manual lathe, and cutting the ring with a knife or any other object.

9. The method of claim 1 wherein the cylindrical ring is formed from a block of material taken from a list of materials including aluminum, Titanium, steel, plastic, and any other structurally rigid material which can be forged or produced into a solid chunk.

10. The method of claim 1 wherein the vehicle wheel rim is a wheel rim taken from the list of wheel rims including a cycle wheel rim, a cart wheel rim, a car wheel rim, and any moving wheeled conveyance wheel rim.

11. The method of claim 1 wherein the rims are aluminum cycle rims turned from forged rings.

12. The method of claim 1 wherein the first step comprises using contoured rollers to roll forged high strength material into a ring close to an actual desired rim size.