Wheeled suitcase

The invention concerns a suitcase which comprises two case halves (3,4) each having a main surface (2) with a carrying handle (5) secured on the upper side (6) of one case half (4), casters (16) disposed at corners (12,14) at one end (8) of the base (10), the casters (16) projecting relative to the base (10) and the adjacent first vertical narrow side (18) of the case halves, and with a pulling handle (22) which is disposed diagonally opposite the casters (16) in the upper region of the second vertical narrow side (10) of the case halves (3,4). According to the invention, disposed at each upper corner (24,26) of the first vertical narrow side (18) is a guide roller (30) which can pivot about an axis (28) parallel with the upper side (6) of the case halves (3,4), the guide roller (30) having at least one caster (32, 34) and the pivot axis (28) being at a spacing of at most approximately 25 mm, and preferably at most 20 mm, from the main surface (2) and/or the upper side (6) of the respective case half (3,4).

BACKGROUND OF THE INVENTION 
Such a suitcase is known, for example, from DE 33 07 838, EP 0 175 022 A 
and EP 0 247 321 A. 
Furthermore, suitcases are known which are provided, at the frontal face 
thereof, with guide roller inserts comprising a small guide roller having 
a diameter of approximately 30 mm. These guide rollers are arranged in a 
recessed manner in a casing embedded in the frontal face of the suitcase. 
The disadvantage of the known guide roller consists in their being 
arranged at a greater distance from the main surfaces of the suitcase, 
whereby the base width between the two guide rollers is small. In 
connection with the small diameter of the guide rollers, the suitcase has 
a strong tendency to tilt, even in the case of a minor unevenness of a 
floor, which tendency requires an increased attention when rolling the 
suitcase. 
SUMMARY OF THE INVENTION 
The invention is based on the object to improve a suitcase of the kind 
mentioned above so that it can be guided in a stable manner without 
tilting, even when rolling in an upright position. 
Advantageously, the invention provides that a guide roller is arranged with 
at least one caster on each of the upper corners of the first vertical 
narrow side of the suitcase, the rotational axis of the guide roller 
having a distance from the main surface of the corresponding case half and 
from the upper surface of the case half which amounts to a maximum of 2.5 
cm, preferably a maximum of 2 cm. 
The arrangement of the rotational axis of the guide roller with a small 
distance from the upper surface of the suitcase and from the main surface 
of the suitcase causes a base width as wide as possible to be formed 
between the two guide rollers on the corners of the suitcase, which base 
width increases the stability of the suitcase. Apart from that, the 
tendency to tilt is reduced by the position of the rotational axis of the 
guide rollers relative to the center of gravity of the suitcase. 
The rotational axis of the casters extends parallel to the vertical narrow 
side of the suitcase at a distance to the rotational axis of the guide 
roller. This offsetting of the axes causes the guide roller to be easily 
steerable due to the lever forces acting thereupon. 
In a preferred exemplary embodiment, it is provided that the at least one 
caster of the guide roller has a diameter of approximately 35 to 70 mm, 
preferably 40 to 60 mm. The use of a larger caster also reduces the 
tendency to tilt in the case of smaller ground beams and obstacles. 
The projecting length of the at least one caster relative to the plane of 
the first vertical narrow side amounts to approximately 15 mm. In the case 
of such a distance, on the one hand, smaller obstacles can still be 
crossed without the suitcase touching down, on the other hand, the guide 
roller does not project beyond the vertical narrow side as far as to be 
disturbing in the normal position of the suitcase. 
Preferably, the guide roller comprises two parallel coaxially arranged 
casters, the running planes thereof extending at the same distance from 
the rotational axis of the guide roller. Such a guide roller provides the 
suitcase with a higher stability and reduces the danger of the suitcase 
tilting to the side. 
In a preferred exemplary embodiment, the guide roller is provided in a 
casing comprising a flange for attachment to the main surface of the upper 
side and the first vertical narrow side. Within the casing, a recess is 
provided in which the guide roller is mounted to be arranged in a recessed 
manner and can be pivoted freely. 
There now follows a more detailed description of an exemplary embodiment of 
the invention with reference to the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The suitcase shown in FIG. 1 consists of two case halves 3,4 each 
comprising a main surface 2 and each comprising a frame 7 adapted to each 
other. A carrying handle 5 is secured approximately in the center of the 
horizontal upper side 6 of the suitcase on the case half 4. On the lower 
end, the usually horizontal base 10 of the suitcase extends parallel to 
the upper side 6, casters 16 being arranged on the suitcase corners 12,14 
on the one end 8 of the base, which casters project relative to the base 
10 and the adjacent first, normally vertical narrow side 18 of the case 
halves 3,4. The casters 16 rotate about a rigid rotational axis extending 
parallel to the base 10 and the narrow side 18. In the upper region of the 
second vertical narrow side 20, a swing-out pulling handle 22 is disposed 
approximately diagonally opposite the casters 16, the handle section of 
which handle extends parallel to the narrow side 20 and the upper side 6. 
A corner protection 15 is provided on each of the upper and lower corners 
of the usually vertical second narrow side 20. 
On each of the upper suitcase corners 24,26 of the first vertical narrow 
side 18, a guide roller 30 pivotable about a rotational axis 28 parallel 
to the upper side 6 of the case halves 3,4 and comprising at least one 
caster 32,34 is provided. The rotational axis 28 has a small distance (a) 
from the main surface 2 and a small distance (b) from the upper side 6 of 
the respective case halves 3,4. This distance amounts to a maximum of 
about 25 mm, preferably to a maximum of 20 mm. 
The guide roller 30 consists of a guide roller housing 48 pivotable about a 
rotational axis 28 parallel to the upper side 6 of the suitcase. Two 
casters 32, 34 arranged at a distance from each other are pivoted on a 
rotational axis 46 orthogonal to the rotational axis 28 and are offset 
relative to the rotational axis 28 by a distance (c). The distance (a) of 
the rotational axis 28 relative to the main surface 2 and the distance (b) 
of the rotational axis 28 relative to the upper side 6 are preferably 
equal. 
In the case of an especially preferred exemplary embodiment, the diameter 
(e) of the casters 32,34 amounts to 50 mm. The mutual distance of the 
guide rollers amounts to 30 mm, while the projection (d) of the casters 
32,34 relative to the first vertical narrow side 18 amounts to about 15 
mm. The distances (a),(b) amount to about 20 to 25 mm. 
The guide roller housing 48 is connected to a casing 40 via a fixed peg 
with a flange 42, the flange 42 being connected to the main surface 2 of 
the upper side 6 and the first vertical narrow side 18 of the two suitcase 
halves 3,4 via rivets 50. For this purpose, a corresponding recess is 
formed in the suitcase walls on the upper suitcase corners 24,26. The 
casing 40 for the guide roller 30 comprises a recess 44 in which the guide 
roller 30 is arranged in a recessed manner, so that it only projects 
beyond the vertical narrow side 18, for example in the position 
represented in the Figures. The guide roller 30 is freely pivotable within 
the recess 44. 
It is evident that the guide rollers 30 can also be arranged without the 
casing 40 in the case halves 24,26 in a recess corresponding to the recess 
44, if the case halves 3,4 are designed correspondingly. 
The small distance (a) between the rotational axis 28 and the main surface 
2 as well as the offset arrangement of the casters 32 relative to the 
rotational axis 28 allow for a base width of support of the suitcase 
practically extending across the entire width of the narrow side 18 of the 
suitcase. If the suitcase is positioned upright so as to run on the two 
casters 16 and the two guide rollers 30, a high stability without tilting 
is ensured, which is even improved by using large casters 32,34. The guide 
rollers 30 with two casters 32,34 have the property to rotate without 
strong resistance so that the suitcase can be guided very easily and 
comfortably by means of the swing-out handle 22 when in the upright 
position, without an increased danger of tilting in the case of a lesser 
unevenness of the ground surface and smaller obstacles. 
Although a preferred embodiment of the invention has been specifically 
illustrated and described herein, it is to be understood that minor 
variations may be made in the apparatus without departing from the spirit 
and scope of the invention, as defined the appended claims.