Tyre chamber

Abstract

The invention relates to a toroidal inner tube (30, 130). The invention is characterized by the fact that the inner tube (30, 130) is in the form of a flexible corrugated tube (40, 140) that is curved to form a closed loop, the tube comprising alternating crest rings (46, 146) and trough rings (48, 148), the tube presenting a radius (R) and, when measured in a plane perpendicular to the axis of the tube, the radial thickness of at least one of the crest rings is less than the radial thickness of at least one of the trough rings (48, 148).

Claims

1. A toroidal inner tube, in the form of a flexible corrugated tube having a central axis and that is curved to form a closed loop with annular grooves along an entire circumference of a cross-section of the closed loop, the flexible corrugated tube comprising alternating crest rings and trough rings presenting radial thicknesses, wherein the crest rings and trough rings are defined relative to the central axis of the flexible corrugated tube, the flexible corrugated tube presenting a radius and an axis and, when measured in a plane perpendicular to the axis of the flexible corrugated tube, the radial thickness of at least one of the crest rings is less than the radial thickness of at least one of the trough rings.

2. The inner tube according to claim 1, wherein each trough ring defines an annular groove that presents a radial depth, the radial depth of at least one of the trough rings varying around the circumference of the flexible corrugated tube.

3. The inner tube according to claim 2, wherein, when measured in a plane extending transversely relative to the axis of the flexible corrugated tube, at least one of the trough rings presents a shape that is oval.

4. The inner tube according to claim 2, wherein the radial depth of at least one of the trough rings varies between a maximum radial depth and a minimum radial depth, at least one of the maximum and minimum radial depths being reached at at least two distinct positions around the circumference of the flexible corrugated tube.

5. The inner tube according to claim 4, wherein when the minimum radial depth is reached at at least two distinct positions around the circumference of the flexible corrugated tube, said at least two distinct positions of the trough ring where the minimum radial depth is reached are diametrically opposite.

6. The inner tube according to claim 4, wherein when the maximum depth is reached at at least two distinct positions around the circumference of the flexible corrugated tube, said at two distinct positions of the trough ring where the maximum radial depth is reached are not diametrically opposite.

7. The inner tube according to claim 4, wherein the radial thickness of at least one of the crest rings varies between a maximum radial thickness and a minimum radial thickness, the maximum radial thickness being reached at at least one of the circumferential positions of the flexible corrugated tube where the minimum radial depth of the trough ring is reached.

8. The inner tube according to claim 7, wherein the minimum radial thickness of the at least one of the crest rings is reached at at least one of the circumferential positions of the flexible corrugated tube where the maximum radial depth of the trough ring is reached.

9. The inner tube according to claim 2, wherein the groove of at least one of the trough rings presents an axial length and, at least one of the crest rings presents a periphery having an axial length that is strictly greater than the axial length of the groove of at least one of the trough rings, when measured in a plane containing the axis of the flexible corrugated tube.

10. The inner tube according to claim 1, wherein the radial thickness of at least one of the crest rings varies around the circumference of the flexible corrugated tube.

11. The inner tube according to claim 1, wherein, when measured in a plane perpendicular to the axis of the flexible corrugated tube, the radial thickness of at least one of the trough rings varies around the circumference of the flexible corrugated tube.

12. The inner tube according to claim 1, wherein, at least one of the crest rings presents a periphery that is substantially flat, when measured in a plane containing the axis of the flexible corrugated tube.

13. The inner tube according to claim 1, wherein at least one of the trough rings presents a section that is rounded, when measured in a plane containing the axis of the flexible corrugated tube.

14. The inner tube according to claim 1, wherein the flexible corrugated tube is made of thermoplastic elastomer (TPE).

15. A wheel configured to be mounted on a vehicle wherein the wheel comprises: a running device comprising a contact surface configured to come into contact with the ground during travel of the vehicle, and defining an internal housing; and an inner tube in the form of a flexible corrugated tube having a central axis and that is curved to form a closed loop, the flexible corrugated tube comprising alternating crest rings and trough rings presenting radial thicknesses, wherein the crest rings and trough rings are defined relative to the central axis of the flexible corrugated tube, each trough ring defining an annular groove that presents a radial depth, the flexible corrugated tube presenting a radius and an axis and, when measured in a plane perpendicular to the axis of the flexible corrugated tube, the radial thickness of at least one of the crest rings is less than the radial thickness of at least one of the trough rings, the inner tube being arranged in the internal housing of the running device.

16. The wheel according to claim 15, wherein the radial depth of at least one of the trough rings varies between a maximum radial depth and a minimum radial depth, at least one of the maximum and minimum radial depths being reached at at least two distinct positions around the circumference of the flexible corrugated tube and wherein one of the circumferential positions of the trough ring where the minimum radial depth is reached is arranged facing the contact surface of the running device.

17. The wheel according to claim 15, wherein the running device includes a first lateral margin and a second lateral margin extending from the contact surface, an inspection port being formed in either one of the first and second lateral margins of the running device.

18. The wheel according to claim 17, wherein the wheel also includes a protective sleeve arranged around the flexible corrugated tube the inner tube and arranged facing the inspection port.

19. The wheel according to claim 18, wherein the flexible corrugated tube forming the inner tube has first and second longitudinal ends and in that the protective sleeve has a closed first end, the protective sleeve being arranged at the first longitudinal end of the flexible corrugated tube, the closed first end being arranged against the second longitudinal end.

20. A toroidal inner tube, wherein the toroidal inner tube is in the form of a flexible corrugated tube that is curved to form a closed loop, the tube comprising alternating crest rings and trough rings presenting radial thicknesses, each trough ring defining an annular groove that presents a radial depth, the tube presenting a radius and an axis and, when measured in a plane perpendicular to the axis of the tube, the radial thickness of at least one of the crest rings is less than the radial thickness of at least one of the trough rings.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Other characteristics and advantages of the invention appear more clearly and more completely on reading the following description of two preferred embodiments, given as non-limiting examples and with reference to the following accompanying drawings, in which:

(2) FIG. 1A is a partially cutaway diagrammatic view of an example of a wheel of the present invention;

(3) FIGS. 1B, 1C, and 1D are diagrams showing the first and second ends of alternative embodiments of the inner tube of the tire of the present invention;

(4) FIGS. 2A and 2B are diagrammatic views in section respectively on a plane across the axis of the tube and on a plane containing the axis of the tube in a first embodiment of a tire inner tube of the present invention;

(5) FIG. 2C is a diagrammatic section view on a plane containing the axis of the tube showing a second embodiment of the tire inner tube of the present invention;

(6) FIGS. 3A, 3B, and 3C are diagrammatic section views respectively on a plane across the axis of the tube and on first and second planes containing the axis of the tube showing a third embodiment of the tire inner tube of the present invention;

(7) FIG. 4 is a diagrammatic view of an example vehicle having the wheel of the present invention installed thereon; and

(8) FIG. 5 is a diagram showing an example of a protective sleeve mounted on one end of the tube of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(9) In the example shown in FIG. 1A, the wheel 10 of the present invention comprises in conventional manner a rim 12 and a running device 14 such as a tire, for example.

(10) The running device 14 presents a contact surface 16 on which shapes in relief may be formed, by way of example and in non-limiting manner, in order to improve grip between the wheel and the ground; in addition, the running device 14 includes a first lateral margin 18 and a second lateral margin, both of which extend from the contact surface 16 to the rim 12.

(11) The running device 14 is mounted on the rim 12 in such a manner that the contact surface 16 and the first lateral margin 18 and the second lateral margin define an internal housing 20 containing an inner tube 30, 130.

(12) As shown in particular in detail in FIG. 1A, where the running device 14 is shown in dashed lines, the inner tube 30, 130 is arranged between the inside face of the contact surface 16 and the periphery of the rim 12.

(13) The term inside face is used of the contact surface 16 to designate the face opposite from its face that is to come into contact with the ground.

(14) The inner tube 30, 130 is toroidal in shape and, in this example, it is made from a corrugated tube 40, 140 that is cylindrical of radius R, and that is curved so as to form a loop.

(15) As shown in FIG. 1A, the tube 40, 140 has a first end 42, 142 and a second end 44, 144 opposite from its first end; the initially straight tube 40, 140 is curved and looped so as to form an open torus, such that the first and second ends 42, 44; 142, 144 come into contact against each other.

(16) It can thus be seen that when the tube 40, 140 is in a closed loop, the first and second ends 42, 44; 142, 144 are in contact with each other of the plane-against-plane type. Such contact of the ends against each other thus enables the tube to be looped, the tube being held between the inside face of the contact surface of the running device 14 and the periphery of the rim 12.

(17) It can thus be understood that the tube 40, 140 can alternate between a straight-line state in which it presents a longitudinal axis A, shown in the following figures, and a curved state, in which it forms an open torus.

(18) The tube 40, 140 is made up of an alternation of crest rings 46, 146 and of trough rings 48, 148.

(19) As can be seen in the various figures, the portions of the tube 40, 140 connecting together two successive rings are rounded, so as to avoid forming sharp edges that might compromise use of the tube 40, 140.

(20) As shown in FIG. 1A, the first and second ends 42, 44; 142, 144 are constituted by trough ring portions 48, 148.

(21) Without going beyond the ambit of the present invention, and as shown in FIG. 1B, it would naturally be possible to devise a tube 40, 140 in which the first and second ends 42, 44; 142, 144 are constituted respectively by a crest ring portion 46, 146 and by a trough ring portion 48, 148. This configuration causes contact between the two ends of the tube to be further improved with the end constituted by a trough ring portion 48, 148 bearing against the surface defined by the crest ring portion 46, 146 constituting the other end.

(22) Alternatively, and without going beyond the ambit of the present invention, the first and second ends 42, 44; 142, 144 may be constituted by two crest ring portions 46, 146 so as to further improve contact between the two ends.

(23) Furthermore, and as shown in FIG. 1C, it is also possible to provide for there to be a closure element 45 arranged in the inside volume of the tube 40, 140 and configured to further improve contact between the first and second ends 42, 44; 142, 144 when the tube 40, 140 is looped. By way of example and in non-limiting manner, the closure element 45 comprises a tube segment of section that is equal to or slightly greater than the inside section of the tube 40, 140, the closure element 45 also including first and second ends 47 and 49 that are embedded or fastened by any other means in the first and second ends 42, 44; 142, 144 respectively of the tube 40, 140. The closure element 45 may thus be engaged by force in the tube 40, 140; it could also optionally be fastened, e.g. by means of adhesive, in the inside volume of the tube 40, 140. The closure element 45 is thus configured to further improve contact between the ends of the tube 40, 140 when the tube is in a closed loop.

(24) FIG. 1D shows an alternative embodiment of the closure element 45, which presents a section that is shaped so as to fit against the inside profile of the tube 40, 140; thus, and as can be seen in the figure, the closure element 45 may have projecting portions configured to be received in the inside volumes of the crest ring portions 46, 146 so as to further improve assembly of the closure element 45, and consequently further improve secure connection between the first and second ends 42, 44; 142, 144 of the tube 40, 140.

(25) The alternation of crest rings and of trough rings ensures that the tube 40, 140 is flexible so as to enable it, when in the straight-line state, to be curved so as to take on the curved state in order to be closed as a loop, thereby forming the inner tube 30, 130 of toroidal shape that is housed in the internal housing 20 of the wheel 10.

(26) It can be understood that when the tube 40, 140 is in the straight-line state, the longitudinal ends of the tube 40, 140 are constituted by the first and second ends 42, 44; 142, 144; furthermore, the length of the tube 40, 140 is equal to or slightly longer than the circumference of the rim 12 of the wheel 10 so as to make it possible to bring the first and second ends 42, 44; 142, 144 into contact with each other.

(27) By way of example and in non-limiting manner, the tube 40, 140 is made of a thermoplastic elastomer (TPE), which thermoplastic elastomer may be a thermoplastic copolyester or an ether-ester block copolymer.

(28) FIGS. 2A and 2B show a first embodiment of the tube 40, the tube 40 in these various figures being shown in its straight-line state.

(29) As can be seen in particular in FIG. 2A, which is a cross-section view on a plane that is transverse and preferably perpendicular to the axis A of the tube 40, each crest ring 46 and each trough ring 48 is substantially circular in shape.

(30) FIG. 2B is a longitudinal section view of the tube 40 on a plane containing the axis A of the tube 40, the tube 40 being in the straight-line state.

(31) The trough rings 48 present respective grooves 60, each groove 60 forming a depression defined by two consecutive crest rings 46.

(32) Each crest ring 46 presents a periphery 62, which, by way of example and in non-limiting manner, is arranged parallel to the bottoms of the grooves 60.

(33) By way of example and in non-limiting manner, the periphery 62 of each crest ring 46 is substantially flat, as is the bottom of the groove 60 of each trough ring 48, thereby defining a section for the trough rings 48. Without going beyond the ambit of the present invention, it is nevertheless possible to devise a tube 40 made up of crest rings 46 and of trough rings 48 in which the peripheries and the respective sections are rounded.

(34) Each crest ring 46 and each trough ring 48 define an axial length 50, 52. The axial length 50 of the crest ring 46 should be understood as being the axial length of the periphery 62 of the crest ring 46, whereas the axial length 52 of the trough ring 48 should be understood as being the axial length of the width of the groove 60 defined between two successive crest rings 46, these axial lengths being considered when the tube 40 is in the straight-line state.

(35) By way of example and in non-limiting manner, in the first embodiment shown in FIGS. 2A and 2B, the axial length 50 of the periphery 62 of a crest ring 46 is strictly greater than the axial length 52 of the groove 60 of a trough ring 48.

(36) Furthermore, each annular groove 60 of the trough ring 48 presents a radial depth 64; the term radial depth 64 is used of the groove 60 of a trough ring 48 to mean the distance between the bottom of the groove 60 and the periphery 62 of the crest rings 46 on either side of the corresponding trough ring 48.

(37) In the first embodiment of the tube 40, the radial depth 64 of all of the annular grooves 60 is constant around the circumference of the tube 40.

(38) The crest rings 46 and the trough rings 48 also define a radial thickness 54, 56 that, in this first embodiment and in non-limiting manner, is constant all around the circumference of the tube 40.

(39) FIG. 2C shows a second embodiment of the tube 40 of the present invention.

(40) This second embodiment is characterized by the fact that at least one of the trough rings 48 presents a radial thickness 56 that is greater than the radial thickness 54 of at least one of the crest rings 46.

(41) By way of example and in non-limiting manner, the radial thicknesses 54, 56 are constant around the circumference of the tube 40.

(42) FIGS. 3A, 3B, and 3C show a third embodiment of the tube 140 of the present invention, the tube 140 being shown in these various figures in the straight-line state.

(43) FIG. 3A is a cross-section view of the tube 140 on a plane that extends transversely, and preferably perpendicularly, relative to the axis A of the tube 140.

(44) In similar manner to the first and second embodiments described above with reference to FIGS. 2A, 2B, and 2C, the tube 140 is constituted by alternating crest rings 146 and trough rings 148, the crest rings 146 and the trough rings 148 respectively presenting peripheries 162 and annular grooves 160.

(45) The crest rings 146 are also substantially circular in shape, whereas, as can be seen more clearly from the description of FIGS. 3B and 3C, the trough rings 148 present a shape that is oval, by way of example and in non-limiting manner.

(46) In addition, the peripheries 162 of the crest rings 146 are substantially flat, whereas the sections of the trough rings 148 as constituted by the bottoms of the grooves 160 are rounded.

(47) FIGS. 3B and 3C are diagrammatic longitudinal section views of the tube 140 on respective first and second planes, the first and second planes both containing the axis A of the tube 140.

(48) As shown in the section view of FIG. 3B on the first plane, and in similar manner to the above-described first and second embodiments, the crest rings 146 and the trough rings 148 define respective first axial lengths 150, 152.

(49) The trough rings 148 also define a first radial depth 164.

(50) In addition, the crest rings 146 and the trough rings 148 define respective first radial thicknesses 154, 156, the first radial thicknesses 154, 156 being defined as the radial thickness of the material of the tube 140 where it forms respectively the crest rings 146 and the trough rings 148.

(51) In the first plane, the section of the tube 140 presents symmetry about the axis A.

(52) Furthermore, the portion of the tube 140 in its straight-line state that is shown in FIG. 3C comprises an alternation of crest rings 146 and of trough rings 148, each defining respective second axial lengths 150, 152 and respective second radial thicknesses 154, 156. In addition, the trough rings 148 define a second radial depth 164.

(53) As can be seen in the various figures showing the second embodiment of the tube 140 in the straight-line state, the radial depth 164, 164 of each trough ring 148 varies around the circumference of the tube 140 between a minimum radial depth Pmin constituted by the first radial depth 164, and a maximum radial depth Pmax constituted by the second radial depth 164. The maximum and minimum radial depths Pmin and Pmax of the trough rings 148 are both reached at two distinct positions around the circumference of the tube 140.

(54) By way of example and in non-limiting manner, in the third embodiment of the tube 140, the distinct positions of the trough rings 148 where the minimum radial depth Pmin is reached are diametrically opposite, whereas the distinct positions of the trough rings 148 where the maximum radial depth Pmax is reached are not diametrically opposite.

(55) It would naturally be possible to devise a tube 140 in which the two distinct positions in which the minimum radial depth Pmin is reached are not diametrically opposite, while the two distinct positions in which the maximum radial depth Pmax is reached are diametrically opposite. It would also be possible to devise a tube 140 in which the maximum and minimum radial depths Pmax and Pmin are each reached in one position only, or indeed in more than two distinct positions around the circumference of the tube 140.

(56) Furthermore, and as shown in the various figures of the second embodiment, the radial thickness 154, 154 of the crest rings 146 varies around the circumference of the tube 140 between a minimum radial thickness Emin constituted by the second radial thickness 154, and a maximum radial thickness Emax constituted by the first radial thickness 154.

(57) Thus, in the third embodiment of the tube 140 and in non-limiting manner, the minimum radial thickness Emin of the crest rings 146 is reached in the position of the circumference of the tube where the maximum radial depth Pmax of the trough rings 148 is reached; conversely, the maximum radial thickness Emax of the crest rings 146 is reached in the position of the circumference of the tube 140 where the minimum radial depth Pmin of the trough ring 148 is reached.

(58) In this third embodiment, the tube 140 thus has two distinct and diametrically opposite positions in which the maximum radial thickness Emax of the crest rings 146 is reached, and two distinct positions that are not diametrically opposite where the minimum radial thickness Emin of the crest rings 146 is reached.

(59) In addition, in this example and in non-limiting manner, the radial thickness 156, 156 of the trough rings 148 may also vary around the circumference of the tube 140.

(60) Furthermore, and in similar manner to the first and second embodiments as described above, the first and second axial lengths 150, 150 of the crest rings 146 may, for example and in non-limiting manner, be greater than the first and second axial lengths 152, 152 respectively of the trough rings 148.

(61) It is also possible to devise a tube 140 in which the first and second axial lengths 150, 150 of the crest rings 146 are equal, and the first and second axial lengths 152, 152 of the trough rings 148 are also equal.

(62) FIG. 4 shows a vehicle 200, specifically a bicycle, comprising a frame 202, a pedal set 204, a front travel member 206 and a rear travel member 208, the rear travel member 208 including a wheel 10 of the present invention.

(63) The rear travel member 208 also has a hub 210 to which the rim 12 of the wheel 10 is fastened. The axis of the torus defined by the inner tube 30, 130 made from the tube 40, 140, which is then in its curved state, coincides with the axis of the hub 210.

(64) As shown in FIG. 4, the wheel 10 includes an inspection port 70 formed in the first lateral margin 18 of the running device 14; for example and in non-limiting manner, the inspection port 70 may be in the form of a substantially rectilinear window.

(65) The inspection port 70 as formed in this way makes it possible to see the inner tube 30, 130 arranged in the internal housing of the wheel 10.

(66) Without going beyond the ambit of the present invention, it is also possible to emphasize the zone of the first lateral margin 18 in which the inspection port 70 is formed by coloring said zone.

(67) The inner tube 30, 130 is thus arranged between the contact surface 16 of the running device 14 of the wheel 10 and the rim 12, and constitutes a flexible structure enabling the rear travel member 208 to be set into rotation by the pedal set 204 in order to cause the vehicle 200 to move.

(68) The inner tube 30, 130 thus takes the place of an inflatable inner tube of the kind used in conventional manner for mounting in vehicle travel members.

(69) When the wheel 10 includes the tube 140 of the third embodiment described above, it is particularly advantageous for one of the positions of the circumference of the tube 140 where the minimum radial depth Pmin is reached to be placed facing the contact surface 16 of the running device 14, so as to benefit from best flexibility properties.

(70) FIG. 5 shows the tube 40, 140 in an intermediate state between its straight-line state and its curved state, prior to being placed in the internal housing of the running device 14 of the wheel 10, a protective sleeve 72 being mounted on the first end 42, 142 of the tube 40, 140.

(71) The protective sleeve 72 presents a cylindrical body defining an internal cavity 74 and including first and second opposite ends 76 and 78, the first end 76 being closed, for example and in non-limiting manner.

(72) The dimensions of the internal cavity 74 of the protective sleeve 72 are equal to or slightly greater than the dimensions of the tube 40, 140 so that the sleeve 72 can be engaged on the first end 42, 142 by being slid along the tube 40, 140, as shown in FIG. 5, until the first end 76 of the protective sleeve 72 comes into abutment against the first end 42, 142 of the tube 40, 140.

(73) By way of example and in non-limiting manner, the protective sleeve 72 may be made of a transparent material so as to protect the first end 42, 142 of the tube 40, 140 placed facing the inspection port 70, while still leaving it visible.

(74) The entire description above is given by way of example and does not limit the invention.

(75) In particular, and as mentioned when describing the third embodiment of the tube 140, the various parameters concerning radial depth, axial length, and radial thickness of the trough rings and of the crest rings may vary around the circumference of the tube 140 in various different ways.

(76) In addition, it is also possible, without going beyond the ambit of the present invention, to devise a tube made up of alternating crest rings and trough rings in which the rings present different dimensions going from one ring to another.

(77) As mentioned above, the tube is made to be flexible by having alternating trough rings and crest rings, thereby enabling the tube to be curved so that it can be placed in the internal housing of running devices of different dimensions, thus enabling the tube to be used to fit wheels of different sizes as a function of the axial length of the tube.

(78) Furthermore, although the tube of the present invention is described by way of example as being fitted to a bicycle, it can also be used for any other type of vehicle, such as a scooter, a motor vehicle, or some other kind of vehicle.