EP2237844A2

EP2237844A2 - Rolling member

Info

Publication number: EP2237844A2
Application number: EP09705794A
Authority: EP
Inventors: Thierry Poichot
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-01-31
Filing date: 2009-01-30
Publication date: 2010-10-13
Anticipated expiration: 2029-01-30
Also published as: FR2927000A1; BRPI0907623A2; ATE522260T1; CN101925385B; CN101925385A; WO2009095625A3; EP2237844B1; WO2009095625A2; US20110059664A1

Abstract

Rolling member comprising a track (2) and a moving part (1) able to move relative to the track (2) and designed to form a rolling strip (10) travelling in a closed circuit, said member being characterized in that the moving part (1) comprises a flexible and continuous movement bead, and the track (2) is designed to guide the moving part (1) along a skew path of variable curvature.

Description

Rolling body

The present invention relates to a running gear, as well as sports equipment, leisure or individual displacement or a vehicle equipped with such a running gear.

The most commonly used running gear is the wheel. In theory, the contact of a wheel with the ground is a line of tangency, the length of which corresponds to the width of the tread. This is the case of wagon wheels on rails as shown in Figure 1a.

The discovery of the rubber allowed the provision of the flexible bandage, to increase the contact surface by crushing of this bandage in contact with the ground as shown in Figure 1b.

Then the invention of the tire and the successive improvements of the tires made it possible to optimize the lateral stiffness and the deformation capacity of this tire, thus increasing the contact surface on the ground as shown in FIG. 1c. To increase the contact surface between a wheel and the ground, it is possible either to widen the tread, to increase the diameter of the wheel, or to increase the capacity of the tire to deform, in particular by using softer materials and / or lower air pressure.

During the displacement, the irregularities of the ground, the holes, the bumps, or any obstacle encountered by the wheel generates an impact, therefore of the forces which are transmitted to the undercarriage and to the mobile equipment.

These efforts can be decomposed according to the three axes:

- Vertical corresponding to gravity,

- Longitudinal corresponding to the direction of displacement - Lateral corresponding to the lateral and centripetal components.

These components are directly proportional to the weight and square of the speed of the mobile equipment.

They are directly related to the granularity of the support, the size of the irregularities and obstacles, the angle of incidence of the impact with the wheel, and the damping capacity of the tire and undercarriage,

They induce reaction forces which also depend on the inertia of the moving elements of the same running gear.

The longitudinal component opposes the movement, generating a waste of energy. The vertical component directly impacts the comfort of the mobile equipment, and it varies the contact pressure on the ground, which can go as far as canceling it, causing a partial or total loss of adhesion.

The lateral component influences the path of movement, especially at a steering wheel.

To reduce these parasitic forces, it is possible to reduce the angle of incidence with the irregularities, by increasing the diameter of the wheel, to increase the capacity of the tire to deform, in particular by using more flexible materials and / or lower air pressure, to develop structures and tire profiles that limit the lateral components, or to reduce the mass of the wheel, and moving parts of the running gear.

Furthermore, the displacement of the wheel on the ground induces friction forces which are proportional to the contact surface, and to the deformation stresses of the tread.

The displacement of the wheel induces an aerodynamic drag proportional to its wing surface and to the square of the speed of displacement.

The rotation of the wheel gives it an inertial energy directly proportional to its moment of inertia, and to the square of its speed of rotation, expressed in radians per second.

Moving the mobile equipment gives it kinetic energy directly proportional to its mass and the square of its speed. This kinetic energy is the sum of the kinetic energies of each of the components of the equipment. The mere integration of the non-exhaustive basic parameters stated above involves compromises, and each context of use involves different compromises.

For example, to reduce ground contact pressure, increase grip, reduce the impact of terrain irregularities and improve obstacle clearance capabilities, all-terrain vehicle wheels are oversized, so they are heavier and the mechanical strength of all components must be increased.

This increase in size results not only in congestion, friction, and increased aerodynamic drag, but also in mass, inertia, and increased potential kinetic energy. This implies heavier, more expensive, and more energy-hungry vehicles for less favorable performance and comfort.

In some cases, it is desirable to have a rolling member which does not have a circular shape such as a wheel, but a profile adapted to a specific application.

In particular, it is known from FR571503 to provide a rolling member non-circular shape in particular to reduce shocks caused by uneven ground.

It seems desirable to provide a rolling member of the aforementioned type to pursue all or part of the following objectives:

- Improve the behavior and comfort on any type of coating,

- allow use on a wide variety of terrains,

- allow a low and stable position of the object or the person supported by the running gear,

- Keep weight, bulk and cost comparable to existing products.

For this purpose, the subject of the present invention is a running gear comprising a trajectory guide and a part that is movable with respect to the trajectory guide intended to form a tread traveling in a closed circuit, characterized in that the movable part comprises a continuous and flexible displacement rod, and the path guide is arranged to guide the moving part on a left trajectory with variable curvature.

The running gear according to the invention behaves in part like a wheel, namely that the movable part, which we call displacement rod, unfolds without friction on the ground, driving, guiding and supporting the vehicle and / or the person who is equipped.

The moving part unfolds in a closed path that is neither circular nor even included in a plane. Indeed, the shape, the dimensions, and the choice of the materials which constitute the displacement bump give it torsion and bending characteristics, which allow it to follow, by elastic deformation, a left closed curved trajectory with variable curvatures. imposed on it by the trajectory guide.

It is designed so that the deformations which are thus imposed to him remain within the limits of its elastic limits, so that its displacement absorbs the minimum of energy. These provisions make it possible to have an area of contact with the ground increased. They also allow:

- to give the wheel drive zone a wide variety of trajectories, depending on the conditions of use. to give the inactive part of the wheel a trajectory that integrates with the dimensional requirements of the equipped vehicle.

- To dampen the irregularities of the support by elastic deformation of a part or the whole of the wheel.

Advantageously, the member comprises revolution rolling elements disposed between a rolling surface of the movable part and the path guide so as to facilitate the relative movement between the path guide and the moving part.

According to one embodiment, the displacement rod is made of elastic material. Advantageously, the bead may have inside a heart of softer material, or a foam, or a vacuum filled with a gas under pressure.

According to one embodiment, the coil comprises several elements made of different materials reported to obtain different mechanical properties for the tread, the running surface and the core.

Advantageously, the bead has inwardly facing impressions of the path intended to cooperate with means intended to constrain the movement in a single direction. According to one embodiment, the member comprises braking means cooperating with the displacement rod.

Advantageously, the flange comprises at least two rolling surfaces between which is disposed a flexible core so as to provide the rigidity necessary for the transmission of the guide forces and holding the displacement rod.

According to one possibility, the trajectory guide comprises rolling tracks for guiding the rolling element movement, the displacement rod comprises one or more rolling surfaces, the rolling elements thus being housed between the rolling surface of the rolling rod. displacement and running track. According to another possibility, the rolling elements comprise a certain number of rollers whose axis of rotation is integral with the path guide, the displacement rod comprising one or more rolling surfaces on which the rolling elements bear. Advantageously, the trajectory guide is arranged so that the coil has several distinct contact zones with the displacement surface.

The present invention also relates to an equipment or pad movement, sports, or leisure individual comprising a rolling member as previously described.

Advantageously, the equipment is equipped with a footrest plate, intended to receive the two feet of the skater, who uses it as a skateboard, a snowboard, or a surf.

The present invention further relates to equipment for any use proper to allow or facilitate the movement of persons or goods comprising a running gear according to the invention or a land, air or sea vehicle comprising such a rolling member.

The invention will be better understood with the aid of the detailed description which is set forth below with reference to the appended drawing in which: FIG. 1a is a diagram illustrating the contact zones between a wheel and a flat ground.

Figure 1b is a diagram illustrating the contact areas between a wheel with a bandage and a flat ground.

Figure 1c is a diagram illustrating the contact areas between a wheel with a tire and a flat ground.

Figure 2 is a side view of the inside of the right leg of the skater of a displacement shoe comprising a first embodiment of a running gear according to the invention.

Figure 3 is a rear view of the displacement pad of Figure 2. Figures 4a, 4b, 5 and 6 show the sectional view of a rolling member according to different embodiments.

Figure 7 is a schematic view illustrating the profile of a movable portion of a rolling member according to the invention according to a variant of the invention. As shown in the figures, a rolling member according to the invention comprises:

a movable part 1 comprising a flexible displacement bead forming a closed curve which takes place on a moving surface, for example a ground such as a tire or a track,

a guide of trajectory 2 of the movable part intended to guide it on a left trajectory with variable curvature.

The rolling member also comprises revolution rolling elements 5 disposed between the movable portion 1 and the path guide 2 so as to ensure a movement with limited friction between these two parts of the member.

According to a first embodiment shown in FIG. 4, the displacement rod comprises on an outwardly facing part of the trajectory and intended to be in contact with the displacement surface a tread 10.

This tread has a profile and sculptures that can be adapted according to the type of displacement surface chosen.

The flange comprises a portion positioned towards the inside of the trajectory of the flange comprising rolling surfaces 11 on which the rolling elements 5 will roll, hard enough for the rolling force to be minimal.

The bead may have inside a heart 12 of softer material, or a foam, or a vacuum filled with a gas under pressure.

These arrangements allow a connection between the tread 10 and the rolling surfaces 11, which reconciles a small lateral deformation of the flange, and a good damping capacity.

It is possible to provide a flange consisting of several elements made of different associated materials in order to obtain the desired properties for the tread, the running surfaces 1 1 the core 12, the body of the flange, any other functional entity, and their connection.

The flange can also have indentations facing towards the inside of the trajectory allow to drive a gear wheel, which can be provided with a freewheel hub, to prohibit the reverse, especially in the climbs, possibly disengageable if necessary and may also optionally have the function of a brake disk. A surface 14, preferably turned towards the inside of the trajectory, may optionally be used as a braking drum.

This surface 14 may also be used to constitute an anti-recoil system by wedging rollers against inclined surfaces, or by wedging eccentric surfaces, possibly still disengageable if necessary

The shape of the displacement rod 1 is imposed by the guide path 2 through the rolling elements 5, allowing a displacement of the roll without friction. Before it is mounted between, on, or around the trajectory guide, it may be a circular, tire-like, flexible ring, the developed one of which is defined by these trajectory guides. This allows it to have a radius of curvature at rest corresponding best to the average of the radii of curvature described during its displacement.

It can also be at rest as a rectilinear element, possibly less expensive to manufacture, which will be closed and fixed on itself ring, before, during, or after its integration with the trajectory guide. The path guide 2 is machined and formed according to the desired displacement path of the displacement rod.

According to a first possibility shown in FIG. 4a, the trajectory guide 2 comprises rolling tracks 2a making it possible to guide the movement of the rolling element, in particular of the ball-bearing type 5a.

Each rolling element 5a is thus housed between the rolling surface 11 of the displacement rod and the rolling track 2a.

According to another possibility shown in FIG. 4b and in FIG. 5, the trajectory guide may also comprise means for fixing rolling elements constituted by at least one roller 5b. The pivot of the roller is secured to the path guide, and the roller rolls on the rolling surface 11 of the displacement rod.

The bearing areas of the rolling elements on the displacement rod are arranged to guide the movement thereof and to avoid lateral movements. Thus, it is possible to provide two rolling surfaces 11 inclined on either side of the bead as shown in FIG.

It is also possible to provide a single rolling surface 11 of convex or concave shape to ensure the shape complementary guidance with the rolling elements 5a.

The trajectory guide 2 and the rolling elements 5 provide the lateral guidance, the different inflections of the trajectory of the flange, the radial guide for rolling on the displacement surface, and a restraint to prevent the flange from escaping ( "off"), or its voltage. The materials chosen for the displacement rod allow it the elasticity necessary to follow the left ovoid displacement path shown in FIGS. 2 and 3 in an elastic manner, it thus restores by releasing all or part of the energy consumed to deform .

This rolling member is particularly adapted to the roller skate:

A pad equipped with a running gear according to the invention comprises a shoe 4 intended to hold the skater's foot or shoe.

The hoof may consist of a shoe that the skater laces or locks around his foot like an ice skate according to a first variant, or may include fastenings allowing to practice with special shoes, such as cross-country ski boots, or mountain shoes for example, according to a second variant shown in Figures 2 and 3.

The natural stability of the equipment makes it possible to offer simple, fast and efficient fastening systems that are compatible with the majority of city and sport shoes, as was the case with older generations of roller skates.

The shoe is fixed on a frame 3 on which is fixed a rolling member as described above. The trajectory of the displacement rod 1 may comprise 6 main distinct zones:

1) the contact zone A with the ground is rectilinear or has a large radius of curvature under the skater's foot, in the vertical plane, and over a greater or lesser length to promote stability, maneuverability, or speed; 2) the attack zone B in front of the foot is raised with a suitable profile, in order to climb on the obstacles and irregularities encountered on its trajectory;

3) the clearance zone C above the front of the foot curves outwardly of the body of the skater, so as to return towards the rear of the skate avoiding the calf of the skater;

4) The lateral zone D can leave the trajectory freedom to the flange so that it can compensate for variations in development due to expansion, wear, or aging of the material;

5) the return zone E behind the skater's foot imposes a trajectory roughly symmetrical to the zone 3;

6) the rear support zone F, to join the curvature of the zone A, and optimized to limit the risk of falling back, and allow the possible integration of a braking system.

The skate according to the invention proposes a simple solution, technically reliable, financially balanced, which brings more stability, more comfort, and a better versatility of use.

It moves on a single rolling member which passes under and approximately in the axis of the foot, whose curvature in contact with the ground can have the optimum profile, and which takes a minimum space under the skater's foot.

The running gear according to the invention makes it possible to develop different ranges of rollers, more comfortable, more stable, safer, and more versatile. According to a third embodiment shown in FIG. 6, the running gear shows the following variants:

The rolling elements 5 can be balls and rollers, and can be maintained by a cage comparable to that which equips the ball bearings, and having the necessary flexibility. The rollers may be cylindrical, or have any other form of revolution.

The shape of the running tracks depends on the shape of the rolling elements, and the constraints to assume.

The number of running lanes depends on the criteria for using the equipment. The displacement rod constitutes an elastic ring comprising, as in the previously described embodiments, a tread 10, rolling surfaces 11.

Advantageously, a flexible core 20 is included in the displacement rod 1, between the rolling surfaces 11 situated on either side of the bead so as to provide the rigidity necessary for the transmission of the guiding and holding forces of the displacement rod. .

The flanks 22 of the flange reconcile a good lateral resistance, and a good damping capacity. As before, the core 12 of the flange is made of softer material, or a foam, or a vacuum filled with a gas under pressure. The boudin can also incorporate an inner tube.

As before, the flange can provide other ancillary functions: Fingerprints on the underside may allow the mechanical training of ancillary elements: braking, freewheel, engine, or other.

The intrados surface can also be used as a brake drum. It is also possible to insert:

magnetic elements making it possible to generate electricity, or even to constitute a linear motor. - elements to measure displacements, speed, pressure, and any other useful information.

The trajectory guide 2 is connected to a vehicle by a connecting element 17 which houses the trajectory guide 2.

The connecting element may have a U-shaped profile forming a housing for the trajectory guide 2. A damping element 18 is advantageously disposed between the trajectory guide and the bottom of the housing.

The path guide 2 is made in one piece or in parts 2c, 2d and 2e, machined or shaped according to the desired travel path to meet the use. Only one guide can support all running surfaces, but these can also be spread over several guide parts. Their number is not limited, it depends on the use.

Each guide portion has one or more integrated or reported rolling surfaces on which the rolling elements 5 will roll. These surfaces may belong to inserts, glued, recessed, overmoulded, or other, or be provided in the guide. The harder they will be, the lower the rolling effort will be.

The path guide provides, through the rolling elements, the lateral, axial and radial guide of the rolling flange, and the transmission of forces. In the case of partial guidance, a recycling circuit of the rolling elements will be incorporated.

The single guide, or all of the guide portions, constitutes the annular hub of the flexible wheel.

The hub may comprise complementary elements, in particular for the attachment and maintenance of the trajectory guide part or parts 2, and for connection to the vehicle. It can comprise several zones, rigid, or more or less flexible, depending on the constraints supported by the portion of trajectory considered, and the functions to be fulfilled: zone of transmission of the forces on the ground, zone of connection with the vehicle, zone of connection to the suspension, deformation zone, etc.

According to the need, and according to the zones of the trajectory, the guide parts can be integrated in an ad hoc imprint of the vehicle, rigidly or elastically or guided by supports connected or articulated on the vehicle, rigidly, or elastic. These guide parts may be otherwise constrained or completely free.

The trajectory guide 2 forms an annular hub that can be flexible.

According to a variant shown in Figure 7, the path guide 2 is arranged so that the coil has a plurality of distinct contact areas with a displacement surface formed for example by the ground.

The running gear according to the invention can be applied to equipment for leisure, travel, or individual transport: Skateboard, wheelchair, stroller, wheelbarrow, luggage, etc. or equip many types of mobile equipment and vehicles.

Moreover, it is possible to add to it, suspension elements, a braking system, an anti-recoil system, disengageable if possible, a motor, and other features or accessories.

Claims

Rolling member comprising: a trajectory guide (2) and a moving part (1) with respect to the trajectory guide (2) intended to form a tread (10) moving in a closed circuit, characterized in that

The movable part (1) constitutes a flexible and continuous displacement bead, and in that the path guide (2) is arranged to guide the movable part (1) on a left trajectory with variable curvature.

2. Body according to claim 1, also comprising revolution rolling elements (5) disposed between a rolling surface (11) of the movable part (1) and the trajectory guide (2) so as to facilitate relative movement. between the trajectory guide and the moving part.

3. Body according to one of the preceding claims, wherein the guide has or comprises one or more flexible parts

4. Body according to one of the preceding claims, wherein the coil (1) may have inside a core (12) of softer material, or a foam, or a vacuum filled with a gas under pressure.

5. Body according to one of claims 2 or 3 and the claim

4, wherein the boud in (1) is an assembly of several elements made of different materials reported to obtain different mechanical properties for the tread, the running surface (1 1) and the heart (12), as well as the elastic flexibility that is needed.

6. Body according to one of the preceding claims, wherein the flange (1) has indentations (13) facing inwardly of the path for cooperating with means for constraining the movement in a single direction.

7. Body according to one of the preceding claims, comprising braking means cooperating with the displacement rod (1).

8. Body according to one of the preceding claims, wherein the coil (1) comprises at least two rolling surfaces between which is disposed a flexible core (20) so as to provide the rigidity necessary for the transmission of the guide forces and holding the displacement rod (1).

9. Body according to one of the preceding claims, wherein the path guide (2) comprises rolling tracks (2a) for guiding the rolling element movement (5), the displacement rod comprises a surface of bearing (1 1), the rolling elements (5) thus being housed between the running surface (11) of the displacement rod and the rolling track (2a).

10. Body according to one of the preceding claims, wherein the rolling elements comprise at least one roller (5b, 5c) whose axis of rotation is integral with the path guide, the displacement rod comprising a running surface ( 11) on which the rolling elements (5b, 5c) bear.

11. Body according to one of the preceding claims, wherein the path guide (2) is arranged so that the coil has several distinct contact areas with a moving surface.

12. Equipment or running pad, sports, or leisure individual comprising a running gear according to one of claims 1 to 11.

13. Equipment according to claim 12, equipped with a footrest plate, intended to receive the two feet of the skater, who uses it as a skateboard, a snowboard, or a surf.

14. Equipment for any purpose that is suitable for enabling or facilitating the movement of persons or goods comprising a running gear according to one of claims 1 to 11.

15. Land, air or sea vehicle comprising a running gear according to one of claims 1 to 11.