The invention is directed to the field of tooling and the field of maintenance of vehicles such as motorbikes. More specifically, the invention is directed to the field of maintenance to the wheels of motorbikes.
BACKGROUND ART
Prior art patent document published DE 20 2014 104 277 U1 discloses a lifting tool for wheels of automotive vehicles. That tool comprises a scissor lifting mechanism with scissor pivoting arms, a lower frame and an upper frame. Each of the lower and upper frames comprises guiding rails for rolls at the ends of the pivoting arms on one longitudinal side of the scissor lifting mechanism. Wheels are mounted on the lower frame for allowing the tool to be moved by rolling on the floor. The scissor lifting mechanism comprises also a threaded spindle assembly for lifting and lowering the upper frame. That assembly cooperates with the upper ends of the scissor pivoting arms. On the upper frame are also mounted two parallel elongate rolls for supporting a wheel of an automotive vehicle. These rolls can be removed and replaced by two U-shaped brackets for engaging with a lower portion of a motorbike's frame for lifting said motorbike. In that configuration, the tool is oriented transversely to the motorbike.
Prior art patent document published FR 2 749 838 A1 discloses also a lifting tool for wheels of automotive vehicles, similar to the tool of the preceding document. In that tool, two bars for supporting the wheel are provided directly on the upper ends of the scissor pivoting arms, thereby avoiding the need of an upper frame as in the preceding document.
Prior art patent document published JP H09-26707 A discloses a lifting tool for a vehicle wheel, comprising a scissor lifting mechanism with scissor pivoting arms; wheels mounted on a bottom portion of the scissor lifting mechanism, for rolling on the floor; two parallel bars on a top portion of the scissor lifting mechanism, for supporting the wheel; wherein the wheels are mounted directly on the scissor pivoting arms.
The above scissor lifting tools are designed for lifting large and heavy wheels of automotive vehicles and even truck wheels. They are therefore expensive and heavy to manipulate. They are not quite suitable for lifting motorbike wheels whose access is along the longitudinal axis of the motorbike, contrary to automotive and truck wheels which are accessed transversely.
Prior art patent document published US 2003/0221303 A1 discloses a third hand stand also referred to as a tire jack for enabling a single person to position and hold the tire/wheel assembly in the proper position while replacing the tire/wheel assembly on the swing arm or frame a motorcycle. The tire jack comprises a tire support, a lever, a means for connecting the tire support to the lever at a position offset from a longitudinal centerline of the tire support, wherein the tire support is oriented transverse to the lever. The tire jack is operated by positioning the tire support of the tire jack underneath the tire/wheel assembly and moving the lever such that the tire/wheel assembly is elevated and moved laterally until the tire/wheel assembly is properly aligned with the swing arm. The tire/wheel assembly is then attached to the motorcycle.
The above lever tire jack is advantageous in that it is light and rapid in use. However it requires a quite accurate handling for reaching the correct height and also to be permanently held while mounting the wheel to the motorbike. It is also not practical for moving and positioning the wheel along the longitudinal axis of the motorbike.
The invention has for technical problem to provide a lifting tool that is practical for mounting and dismounting motorbike wheels, and that is simple and cheap to manufacture.
The invention is directed to a lifting tool for a vehicle wheel, comprising: a scissor lifting mechanism with scissor pivoting arms; wheels mounted on a bottom portion of the scissor lifting mechanism, for rolling on the floor; two parallel bars on a top portion of the scissor lifting mechanism, for supporting the wheel; wherein the wheels are mounted directly on the scissor pivoting arms.
According to a preferred embodiment, the scissor lifting mechanism comprises two distant and parallel pairs of the scissor pivoting arms, the wheels comprising four wheels, each of said wheels being mounted on a lower end of one of the arms, respectively.
According to a preferred embodiment, the two parallel bars are mounted directly on the scissor pivoting arms, two opposed ends of each of said bars being attached to upper ends of two distant and parallel arms of said arms, respectively.
According to a preferred embodiment, the scissor lifting mechanism further comprises two transverse arms each interconnecting the lower ends of two distant and parallel arms of the scissor pivoting arms, respectively.
According to a preferred embodiment, the scissor lifting mechanism comprises a spindle assembly for varying the distance between lower ends of the scissor pivoting arms.
According to a preferred embodiment, the spindle assembly comprises a threaded spindle extending through the transverse arms, said spindle abutting against a first one of said arms and engaging with a corresponding thread on the second of said arms.
According to a preferred embodiment, the scissor lifting mechanism comprises resilient means allowing an automatic lift movement of said mechanism until the bars reach the wheel lifted up from the floor.
According to a preferred embodiment, the resilient means comprise at least one traction spring with two ends anchored to the transverse arms or to the lower ends of one of the pairs of scissor pivoting arms, respectively.
According to a preferred embodiment, the spindle assembly is configured such that it slides freely through the first transverse arm during the automatic lift movement of the scissor lifting mechanism.
According to a preferred embodiment, the scissor lifting mechanism is configured such that the scissor pivoting arms of each pair of said arms are aligned in a lower position.
According to a preferred embodiment, one of the arms of each pair of scissor pivoting arms shows a recess for accommodating, the lower position, the bar or a wheel axe on the other arm of said pair.
According to a preferred embodiment, at least two of the wheels are swivel wheels, said wheels being preferably at one longitudinal end of the scissor lifting mechanism.
The invention is particularly interesting in that it provides a lifting tool that is particularly adapted for supporting a motorbike wheel, i.e. by showing a reduced height in a lower configuration and by being of a simple and therefore cheap construction. Most of the operators and motorbike owners take uncomfortable positions for releasing the weight of a motorbike wheel when removing the wheel axle, e.g. by bending their body above the rear part of the seat or even the tail of the motorbike and by extending one of their arms downwardly to grip an upper portion of the wheel rim. While this might work out when removing the axle for dismounting the wheel, this is much more difficult when remounting said wheel. Especially at the rear, the wheel needs to be aligned not only with the two oblong holes in the swing arms but also with a rear brake holder, for allowing insertion of the axle. In other words, the position in height of the wheel needs to be accurately adjusted for a proper and comfortable reinsertion of the axle. The invention avoids also potential damages to the brakes (calliper, brake pads and holder) and other surrounding parts of the motorbike while removing the axle and while positioning the wheel for insertion of said axle.
The lifting tool of the invention provides therefore a particularly convenient and adapted tool.
The motorbike 2 comprises a rear wheel 4 that is mounted on the rear swing arms 6. As is apparent in
A lifting tool 10 is positioned under the rear wheel 4 and lifted up to contact said wheel so as to facilitate its dismounting from, and remounting on, the motorbike. Indeed, once the rear wheel is slightly lifted up, the wheel axle can be extracted out of the swing arms and the wheel without having to exert high efforts since the weight of the wheel does not act anymore on said axle.
The lifting tool 10 comprises a scissor lifting mechanism 12 with scissor pivoting arms 14. For instance, the scissor lifting mechanism 12 comprises two pairs of scissor pivoting arms, said pairs of arms being distant and parallel so as to be on each lateral side of the wheel when the lifting tool is in position under the wheel. Supporting bars 16 are attached to the upper ends of the scissor pivoting arms 14, said bars being for contacting the running surface of the wheel tire. The scissor lifting mechanism 12 comprises also a threaded spindle assembly 18 that cooperates with the lower ends of the scissor pivoting arms 14. Wheels 20 are mounted on the lower ends of the scissor pivoting arms 14.
In
In
In
It goes without saying that what has been presented in relation with
Each of the scissor pivoting arms 14 of the scissor lifting mechanism 12 comprises a top end 14.1 and a lower end 14.2. These end are at top and end positions when the scissor lifting mechanism 12 is in a lifted configuration, as illustrated in
As is apparent in
It is to be mentioned that in alternative to the above recesses 14.3, the outer arms 14 of the two pairs of scissor pivoting arms could be designed longer so that their top ends 14.1 would end beyond the lower ends 14.2 of the inner arms 14 (on the right side in
As this is apparent in
It shall be noticed that the engagement between the spindle 18 and the arms 14, for instance via the transverse arms 26, can show means that compensate the change of relative orientation between the arms 14 and the spindle 18. Indeed, in the lower configuration, the main directions of the arms and the spindle are essentially in the same plane, or at least parallel, whereas in the lifted configuration the arms are inclined relative to the horizontal plane comprising the axis of the spindle. Such compensating means can be means that allow a relative pivoting between the surfaces in contact with the spindle and the arms. For example, the transverse arms 26 could be pivotably mounted on the lower ends 14.2 of the arms. Alternatively, the transverse arms 26 could comprise pivotably mounted elements engaging with the spindle. Other mechanical compensation means, as such well known to the skilled person, can be considered.
The resilient means 24 comprise for instance two traction helical springs 24 anchored at both ends, each, at the transverse arms 26, so as to exert a resilient traction force between these two arms 26, tending to move these arms closer to each other. When the arms of each pair of scissor pivoting arms 14 are aligned, the lifting force normally produced by the resilient means 24 is absent or at least close to zero. Once the scissor lifting mechanism is manually lifted, the arms 14 of each pair of scissor pivoting arms are not aligned anymore and the attraction force of the resilient means 24 is converted into a lifting movement of the scissor lifting mechanism.
It goes without saying that the resilient means could take other forms, e.g.
the spring(s) could be anchored to the arms 14 directly, or even torsion springs could be provided at the pivots between each pair of scissor pivoting arms. In such a case, an arresting mechanism could be provided between the arms for retaining them in the lower configuration against the resilient force of the resilient means. The release of that mechanism would then free the pivoting movement between these arms and allow the lifting tool to lift up towards the wheel.
The different arms and bars constituting the above lifting tool can be made of metal, like steel or aluminium, and/or of plastic material. They could also be made of wood. The connection between the different elements can therefore be achieved by several methods, like screwing, welding (when made of metal) and/or gluing.
The above lifting tool is particularly interesting in that it can show a reduced height in a lower configuration, enabling it to be rolled under a jacked-up wheel of a motorbike while being of a simple construction and particularly adapted for supporting a motorbike wheel.
Number | Date | Country | Kind |
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LU100512 | Nov 2017 | LU | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2018/080358 | 11/6/2018 | WO | 00 |