Fixed-adjustment hub for spoked bicycle wheels
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to spoked bicycle wheels and more particularly to a fixed adjustment hub for spoked bicycle wheels. 
     2. Description of the Prior Art 
     Bicycle wheel hubs of known type have an axle threaded at the two ends thereof on which are screwed two cylindrical parts each having an annular groove serving as the inner race for an oblique contact bearing. A tubular part has flat flanges at the two ends thereof carrying two outer races which together with the grooves in the cylindrical parts and the balls form two oblique contact bearings of the hub. The spokes are hooked to the periphery of the flange and attached to the rim to form the wheel. 
     The adjustment of the wheel hub for the known type of bicycle is effected by screwing in or unscrewing of one of the two mentioned cylindrical parts on the threaded axle. This adjustment is rather difficult to achieve. Furthermore, every time the wheel is removed, a cylindrical part can be accidentally tightened or loosened and the hub is then out of adjustment. 
     The quality of oblique contact bearings realized in this construction of a wheel hub is not excellent and sealing against dust and water is imperfect. 
     Moreover, the dimension of the spoke-holding flange differs among the makers and types of bicycles and, consequently, a great many models of hubs must be made to satisfy the demand. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the invention to provide a wheel hub which does not go out of adjustment while the hub is connected to the rim of the bicycle wheel by the spokes. 
     Briefly, in accordance with the present invention, the foregoing and other objects are obtained by providing a fixed-adjustment bicycle wheel hub having two outer flanges to which the spokes are hooked and which hold between them by the tension of the spokes an assembly formed by a cylindrical crosspiece, an axle-threaded at the two ends thereof for mounting the wheel in a self-evident manner on the bicycle and two bearings, the inner race of at least one of the bearings being held so as not to slide on the threaded axle. 
     In a second embodiment of the invention, two oblique contact bearings are used. The two flanges then apply pressure through the rolling elements of the bearings from the outer to the inner races of the bearings both of which are held fixed on the hub axle by two retaining rings provided on the axle. 
     The cylindrical crosspiece is then assembled with the axle, the bearings and the flanges such that it is likewise clamped between the flanges. 
     The flanges described in the second embodiment of the invention can be the outer races of the aforementioned oblique contact bearing. 
     The dissociation of the bearing elements and the holding elements on the one hand, and externally, the flanges and the crosspiece, permits use of different outer diameter flanges with the same rotating assembly, as well as the use of the materials best suited to the function of each element. 
     The hub described is, of course, compatible with all the known arrangements for attaching hubs to bicycles, whether by nuts, butterfly nuts, or by quick attachment with an eccentric device, requiring a hollow axle in such case. 
     It is likewise possible, in all embodiments of hubs conforming to the invention, to fasten a free wheel on one of the flanges of the hub, either by screw threads according to the traditional method or by lateral attachment by means of bolts. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings, wherein like reference characters designate like or corresponding parts throughout the several views, and in which: 
     FIG. 1 shows a section of a first embodiment of a hub conforming to the present invention; and 
     FIG. 2 shows a section of a second embodiment of a hub, of lighter construction, conforming to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference first to FIG. 1, an axle of a hub has two threaded ends 1a and 1b, and an annular groove 1c relatively close to the base of the thread at end 1a. 
     Against a retaining ring 2 set in groove 1c is butted the inner race 3a of a ball bearing protected by the deflector 3c, this inner race 3a being held fixed on the axle 1 by a nut 4 screwed on the threaded end 1a of axle 1. 
     The outer race 3b of bearing 3 is pressed into the cylindrical end 5a of a tubular crosspiece 5. 
     In the other cylindrical end 5b of the crosspiece 5 is contained with a sliding fit the outer race 6b of a second protected bearing similar to the aforementioned bearing 3, and which is likewise provided with a protecting deflector 6c. 
     The inner race 6a of bearing 6 can slide on a non-threaded part of the axle 1 and is at a certain distance from a second nut 4 screwed to the base of the threads on the threaded end 1b of the axle 1. 
     Two flanges 7 capable of sliding on the cylindrical terminations 5a of the tubular crosspiece 5 are pressed firmly against the outer races 3b  and 6b of bearings 3 and 6, towards one another by the tension of the spokes 8 hooked in the holes 7a of flanges 7 the inner shape of which permits realizing a baffle between them and the nuts 4, which improves the sealing of the bearings. 
     FIG. 2 shows a second embodiment using a lighter hub compared to the version shown in FIG. 1. 
     An axle 1 with two threaded ends 1a and 1b is shown having two annular grooves 1c at a certain distance from the aforementioned threaded ends 1a and 1b. The annular grooves 1c each is likewise provided with a retaining ring 2. 
     The bearings 3 are of the oblique contact type, that is, the bearing races are disposed substantially parallel to each other and are inclined relative to the axle 1, and possess an inner race 3a butted against a retaining ring 2. The outer race 3b is an annular inner portion of flange 7. The balls 3c are located between the races 3a and 3b of the oblique contact bearings. 
     In this embodiment, the nuts 4 are screwed to the base of the threads on the threaded ends 1a and 1b of the axle 1 at a certain distance from the inner race 3a of the bearings 3. 
     The tubular part 5 rests at its ends against the inner sides of the flanges 7 and must be of the right length to assure proper tightness of the races of the oblique contact bearings 3 and to give the necessary play in functioning. 
     It may be noted that in the two embodiments described above, the adjustment of the hub cannot be affected in the process of removing the wheel and that to change the adjustment, the hub must be entirely disassembled, which likewise requires removal of the spokes 8. 
     Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is to be understood therefore that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.