A suitcase

BACKGROUND OF THE INVENTION

The invention relates to luggage, in particular suitcases which can be pulled by a person, such as a stroller case, trolley or a roll along.

Such a suitcase typically comprises a first end and a second end opposite the first end with a handle arranged at the first end for pulling the suitcase by a person. Arranged at the second side are a plurality of wheels to support the suitcase from the ground and provide low-friction mobility of the suitcase.

However, a drawback of many commercially available suitcases is that pulling the suitcases over the street or sidewalk may result in a loud noise and corresponding vibrations in the suitcase, which are both undesired.

DE 10 2011 120 353 Al provides a solution using a track. However, in practice the track of this prior art solution provides a significant resistance during rolling and still suffers from noise and corresponding vibrations.

SUMMARY OF THE INVENTION

In view of the above it is an object of the invention to provide a suitcase with a reduced noise level and/or vibrations during pulling.

According to an embodiment of the invention, there is provided a suitcase comprising a first end and a second end opposite the first end, a handle arranged at the first end for pulling the suitcase by a person, a track arranged at a front side of the second end for supporting the suitcase from the ground, and a support element at a rear side of the second end, wherein the track is pivotably connected to the second end of the suitcase to allow the suitcase to pivot about a pivot axis between an upright position in which the suitcase is supported by the ground via the track and the support element, and an inclined position in which the suitcase is inclined forward relative to the upright position and only supported by the track, wherein the track comprises a support surface for engagement with the ground, wherein the support surface has a front portion extending forward from the pivot axis, and a rear portion extending rearward from the pivot axis, and wherein the track is pivotable relative to the second end of the suitcase over an angle of at most 90 degrees.

The invention is based on the insight that the provision of a track with a larger support surface than a wheel will make the suitcase less susceptible for unevenness of the street or sidewalk and thus reduce the vibrations and sound level produced during pulling of the suitcase.

The invention is further based on the insight that the support surface of the track needs to have a front portion in front of the pivot axis and a rear portion extending rearward from the pivot axis to aid in maintaining the support surface in substantially full contact with the ground in all positions. An additional advantage may be that in the inclined position, the person holding the handle of the suitcase experiences ("feels") less weight compared to a prior art suitcase with wheels only, due to a smaller horizontal distance between support surface and center of gravity of the suitcase.

The invention is also based on the insight that the pivotability of the track needs to be limited to at most 90 degrees. The pivotability is beneficial for keeping the support surface substantially horizontal while the suitcase is inclined. The pivotability is further beneficial when a substantially larger obstacle is encountered thereby allowing to pivot backwards upon impact thereby absorbing the impact and minimizing the noise and vibrations. However, the track is not able to pivot more than 90 degrees as is for instance the intention of the track in DE 102011 120 353 Al and in the set of wheels of JP2002- 264605A. As a result, the track and set of wheels of these prior art disclosures will result in a forward roll of the track and the set of wheels which is accelerated by the weight of the suitcase and forward motion of the suitcase thereby having a substantially hard impact on the ground when completing a 120 degrees rotation resulting in noise and vibrations. By limiting the pivot angle of the track, the track is prevented from toppling over and causing noise and vibrations, but will pivot back to the situation with the support surface being substantially horizontal which has a softer landing than the forward motion of the prior art disclosures.

Chinese patent publication CN110638169A discloses a suitcase with a track. However, due to one end of the support surface of the track coinciding with the pivot axis between track and suitcase, this patent publication does not disclose a front portion of the support surface extending forward from the pivot axis. As a result, when the suitcase is pulled in an inclined orientation as shown in Fig. 4, the track will tend to tip forward, thereby significantly reducing the surface area engaging with the ground. Hence, the reduction of vibrations and sound during pulling is minimal, if not absent. It is further noted that the purpose of the track in CN110638169 is to make it easier to climb a stair with the suitcase without being carried, which is different from the purpose of the track of the suitcase according to the invention.

In an embodiment, the track extends beyond the suitcase at the front side of the suitcase when in the upright portion. This may further aid in reducing the weight experienced by a person holding the handle of the suitcase in the inclined position of the suitcase. Yet another advantage may be that in case larger obstacles are encountered, such as curbs or stairs, and the track will pivot back to the upright orientation relative to the rest of the suitcase upon contact with the obstacle while the suitcase is held in an inclined position, the portion extending beyond the suitcase at the front side will prevent the rest of the suitcase from colliding with the obstacle and thus prevent damage or wear of the suitcase.

In an embodiment, the track may be arranged at or near a center of the suitcase. In another embodiment, the track is a left track arranged at a left side of the suitcase, wherein the suitcase further comprises a right track similar to the left track and arranged at a right side of the suitcase. An advantage of using a single track at or near the center of the suitcase is that less components are required and driving of the track may be easier. An advantage of using two tracks at the sides of the suitcase may be that stability may be increased and/or that available space inside the suitcase may be larger or more convenient/practical for holding personal items.

In an embodiment, the track includes a flexible endless element for engagement with the ground and guided by a plurality of guiding elements. The endless element is flexible to allow continued rotation about the plurality of guiding elements and provide a support surface. The endless element may be elastically deformable to allow it to adapt its shape to the ground at the support surface to a certain degree thereby reducing/damping vibrations and thus sound. Alternatively, or additionally, one or more of the guiding elements may include elastic material and/or be elastically deformable to reduce/damp vibrations.

In an embodiment, at least three guiding elements are provided at the support surface of the track to support the endless element. An advantage thereof, is that loads on the support surface can be distributed more effectively.

In an embodiment, the pivot axis of the track coincides with a rotation axis of one of the guiding elements.

In an embodiment, the suitcase includes a motor, a power source and a control unit to drive the motor using the power source. An advantage thereof may be that any possible increase in pulling resistance compared to prior art wheels may be compensated. It may further allow the suitcase to move autonomously, e.g. in a follow mode.

The motor may for instance be connected to one of the guiding elements to rotate the guiding element, thereby rotating the track. The track and the actuatable, i.e. the by the motor rotatable, guiding element may include an associated gear portion to mesh with each other thereby reducing the risk of slip between the guiding element and the track. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in a non-limiting way by reference to the accompanying drawings in which like parts are indicated by like reference symbols, and in which:

Fig. 1 schematically depicts a front view of a suitcase according to an embodiment of the invention,

Fig. 2 schematically depicts a side view of the suitcase of Fig. 1 in an upright position,

Fig. 3 schematically depicts a side view of the suitcase of Fig. 1 in an inclined position,

Fig. 4 schematically depicts in more detail a side view of a second side of the suitcase of Fig. 1 in the inclined position,

Fig. 5 schematically depicts a side view of a track of the suitcase of Fig. 1,

Fig. 6 schematically depicts a rear view of the track of Fig. 5, and

Fig. 7 schematically depicts an exploded view of the track of Fig. 6.

DETAILED DESCRIPTION OF THE INVENTION

Figs. 1-7 schematically depict a suitcase 1 according to an embodiment of the invention.

Fig. 1 depicts a front view, Fig. 2 depicts a side view with the suitcase 1 in an upright position, Fig. 3 depicts a side view with the suitcase 1 in an inclined position, Fig. 4 depicts in more detail a second side 12 of the suitcase 1 of Fig. 3, Fig. 5 depicts a side view of a track 20 of the suitcase, Fig. 6 depicts a rear view of the track 20, and Fig. 7 depicts an exploded view of the track 20.

The suitcase 1 comprises a first end 11 and a second end 12 opposite the first end. A handle 13 is arranged at the first end 11 for pulling (or pushing) the suitcase 1 by a person. The handle 13 is depicted in an extended position but may be retractable, as is known in the art, to reduce the dimensions of the suitcase 1 when not being pulled or pushed.

The suitcase 1 further comprises a track 20, in this embodiment two tracks 20, arranged at a front side FS of the second side 12 for supporting the suitcase 1 from the ground G, and a support element 14, in this embodiment two support elements 14, at a rear side RS of the second side 12. One track 20 is arranged at a left side of the suitcase 1 while the other track 20 is arranged at a right side of the suitcase 1. The tracks 20 may thus alternatively be referred to as left track 20 and right track 20.

The tracks 20 are pivotably connected to the second end 12 of the suitcase 1 to pivot about a pivot axis PA between an upright position as shown in Figs. 1 and 2, in which the suitcase 1 is supported by the ground G via the tracks 20 and the support elements 14, and an inclined position as shown in Figs. 3 and 4, in which the suitcase 1 is inclined forward relative to the upright position and only supported by the tracks 20.

It is noted here that the forward direction FD is the direction that is normally used to pull the suitcase forward by a person. The front side FS of the suitcase 1 is the side of the suitcase 1 that faces in the forward direction FD when being pulled. In this embodiment, the front side FS is the side of the suitcase 1 where the handle 13 is located. Also the left and right locations of the tracks are defined relative to the forward direction FD.

The tracks 20 each comprise a support surface 21 for engagement with the ground G. The support surface 21 has a front portion 21a extending forward from the pivot axis PA and a rear portion 21b extending rearward from the pivot axis PA.

In this embodiment, the suitcase 1 includes a shell 15 to enclose a space to hold items to be transported with the suitcase 1. In this case, the shell may be (semi-)rigid and include two halves 15a, 15b that may be connected to each other using a zip. Shell half 15a may also be referred to as the front half and shell half 15b may also be referred to as rear half.

An advantage of using two such halves 15a, 15b, is that only half 15a needs to be relatively complex to hold the tracks 20 and the handle 13 and the other half 15b can stay relatively simple. It also allows to apply the invention to a prior art suitcase without having to adapt the rear half 15b. Referring to Fig. 2, the track 20 has a track portion 20a extending beyond the suitcase at the front side FS of the suitcase 1 when in the upright position. Preferably, the track portion 20a includes at least partially the front portion 21a of the support surface 21.

As can be clearly seen in Fig. 4, the suitcase 1, in particular the shell 15, includes a recessed part 15c to partially accommodate a track 20. Preferably, the recessed part 15c and the corresponding track 20 are configured such that the track 20 does not extend sideways beyond the suitcase, keeping the outer dimensions of the suitcase 1 within limits.

The recessed part 15c may further be configured to engage with a part of the track or supporting structure thereof when in the inclined position thereby limiting the available pivot angle of the track relative to the second end of the suitcase to at most 90 degrees, preferably at most 80 degrees, more preferably at most 70 degrees, even more preferablt at most 60 degrees.

Reference is now made to Figs. 5-7, which depict a track 20 of the suitcase 1 in more detail. The shown track 20 includes a plate-like mounting body 22 with three lower axles 23a, 23b, 23c and an upper axle 24, all axles being configured to rotatably carry a guiding element, in this case a guiding roll 25a on lower axle 23a, a guiding roll 25b on lower axle 23b, a guiding roll 25c on lower axle 23c, and a guiding roll 26 on axle 24.

All guiding rolls include two grooves to receive and guide two flexible endless elements 27, 28., which may for instance be rubber rings. The guiding rolls 25a, 25b, 25c are arranged to guide the endless elements 27, 28 at the support surface 21 of the track 20. The guiding roll 26 is arranged to apply a bias pressure on the endless elements 27, 28 to tension the endless elements. Resulting friction between one of the guiding rolls, preferably guiding roll 26, and the endless elements 27, 28 may be used to drive the endless elements to move the suitcase 1 using the track 20. The guiding rolls 25a, 25b, 25c, 26 are in this embodiment connected to the respective axles using a bolt 28 and a ring 29, which bolt 28 is received in a threaded female portion of the respective axle.

Connected to the mounting body 22 or the axle 24 is a cylindrical member 30. A first clamping member 31, a second clamping member 32 and a clamping nut 33 are provided to be slidingly received over the cylindrical member 30 to be arranged at opposite sides of a hole in shell 15 of the suitcase 1. The first clamping member 31 includes a threaded male portion 31a to mate with the clamping nut 33 allowing to clamp the shell 15 between the first and second clamping members 31, 32 to rotatably connect the track 20 to the suitcase 1.

The cylindrical member 30 further includes a threaded portion at a free end thereof to mate with another nut 34 allowing to removably attach the mounting body 22 to the suitcase 1 and prevent the track 20 from inadvertently falling off. A ring 35 may be provided between the clamping nut 33 and the nut 34. When the cylindrical member 30 is connected to the axle 24, the cylindrical member 30, nut 34 and axle 24 may be used to drive the guiding roll 26 of the track 20. To this end, the suitcase 1 may be provided with a driving axle 40, a motor 41, a power source such as a battery 42, and a control unit 43 to drive the motor 41 using the power source 42, see dashed optional components in Fig. 1. The control unit 43 may control the motor 41 using users input that may be provided using control elements in the handle 13.

Although support elements 14 are simply depicted as spacers, blocks, or the like components, the support elements 14 may also be wheels or any other kind of support element.

Although in the above example, two flexible endless elements have been depicted, the invention also applies to the use of just one endless element per track 20 or to the use of more than two endless elements per track 20.