Locking system for vehicle wheels

A locking system for a vehicle wheel has a threaded member having a threaded part which has an axis and is screwable in a corresponding counter part, and a plurality of rings which are freely rotatable relative to the threaded part and having different eccentricities, and a key having an axis and a part engageable with the threaded member and is provided with a plurality of formations which engage the rings of the threaded member and have eccentricities similar to the eccentricities of the rings.

BACKGROUND OF THE INVENTION 
The present invention relates to a locking system for vehicle wheels. 
It is known that there are many instances when vehicle wheels or hub caps 
for vehicle wheels are removed by unauthorized persons and stolen. It is 
therefore advisable to provide such a locking system which will not allow 
an unauthorized person to remove a vehicle wheel or at least will make 
such removal extremely difficult. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to provide a new 
locking system for vehicle wheels. 
In keeping with these objects and with others which will become apparent 
hereinafter, one feature of the present invention resides, briefly stated, 
in a locking system which includes a threaded member for holding a vehicle 
wheel on a wheel disk or for holding a hub cap on a vehicle wheel, the 
threaded member having a threaded portion to be screwed with a 
corresponding part of the wheel hub or the vehicle wheel, and an outwardly 
extending part which includes a plurality of portions which are radially 
offset from one another; and a key which as a plurality of engaging 
portions which are correspondingly radially offset relative to one another 
and engageable with the portions of the outwardly extending part of the 
threaded member so as to engage the same and to unscrew the threaded 
member. 
Wherein the system is designed in accordance with the present invention, 
only a special key can unscrew the threaded member and therefore the wheel 
or the wheel hub. 
The novel features which are considered as characteristic for the present 
invention are set forth in particular in the appended claims. The 
invention itself, however, both as to its construction and its method of 
operation, together with additional objects and advantages thereof, will 
be best understood from the following description of specific embodiments 
when read in connection with the accompanying drawings.

DESCRIPTION OF PREFERRED EMBODIMENTS 
FIG. 1 shows a nut of a locking system for a vehicle wheel or a hub cap in 
accordance with the present invention. The nut has a threaded part which 
is identified as a whole with reference numeral 1 and provided with an 
inner threaded opening to be screwed on a threaded pin and the like. A 
lower end 2 of the threaded part 1 is formed as a standard cone or a 
semi-sphere. The threaded part 1 is stepped and has a plurality of 
cylindrical portions 3 with diameters reducing from a lower end to an 
upper end. The axes of the cylindrical portions are offset relative to one 
another in one direction perpendicular to the central axis or even in two 
directions which are perpendicular to the central axis as shown in FIG. 2. 
Cylindrical rings 4 and 5 are freely turnably arranged on the portions 3 
of the threaded part 1 and have a uniform thickness over their periphery. 
The upper portion of the threaded member 1 and the upper ring or cup 6 are 
provided with aligned grooves and a retaining member 7 formed as a spring 
is located in the grooves. 
The locking system further has a key which is identified with reference 
numeral 8. The key here is formed as a key with the inner opening 
engageable with the outer surface of the nut. The inner opening is 
provided with a plurality of steps 9 which are located one after the other 
in the axial direction and are transversely offset relative to one another 
exactly in correspondence with the offset of the corresponding portions of 
the nut, or more particularly in correspondence with the eccentricity 
shown in FIG. 2. The key 8 further has an engaging part 10 to be engaged 
by a tool. When the key 8 is fitted on the nut, the rings 4, 5, and 6 are 
received in the corresponding steps 9 of the central opening of the key. 
By turning the engaging part 9 formed here as a hexagon, by a tool, the 
key 8 is turned and can unscrew the nut from the threaded pin and the 
like. It is impossible to unscrew the nut by any other tool, since any 
tool which engages one of the rings 4, 5, and 6 will just turn the rings 
about their axis without unscrewing the whole nut. 
FIG. 4 shows a bolt of a locking system in accordance with the present 
invention. The bolt has a threaded part 1' which is screwable into a 
corresponding threaded opening. The head of the bolt is provided with a 
plurality of stepped portions 3' identical to the stepped portions 3 of 
the nut shown in FIG. 1, and a plurality of rings 4' and cup 5' are 
arranged on the stepped portions 3'. The lower end of the head is standard 
semi-spherical or conical. The bolt shown in FIG. 4 operates similarly to 
the nut shown in FIG. 1. The key 7 can unscrew the bolt from the threaded 
opening, while any other key engaging the rings 4, 5 will just turn the 
rings but not unscrew the threaded member as a whole. 
It will be understood that each of the elements described above, or two or 
more together, may also find a useful application in other types of 
constructions differing from the types described above. 
While the invention has been illustrated and described as embodied in 
locking system, it is not intended to be limited to the details shown, 
since various modifications and structural changes may be made without 
departing in any way from the spirit of the present invention. 
Without further analysis, the foregoing will so fully reveal the gist of 
the present invention that others can, by applying current knowledge, 
readily adapt it for various applications without omitting features that, 
from the standpoint of prior art, fairly constitute essential 
characteristics of the generic or specific aspects of this invention.