Device for a vehicle air spring, access plug, fork and vehicle comprising such a device

Abstract

The invention relates to a device (20) for an air spring (60) of a vehicle, the air spring comprising a piston (62) moving along an axis (21) in a cylinder (61) and a cylinder access plug (63) placed on the axis of movement of the piston, the device being characterized in that it comprises: - at least one removable shim made of a material configured to absorb vibrations and / or filtration, comprising an assembly relief for assembly with at least one armature, - a support comprising a means for fastening to the access plug and the at least one armature, the at least one armature being configured to be assembled with the assembly relief of at least one removable shim and configured to receive at least one removable shim.

Description

[0001] DESCRIPTION

[0002] TITLE OF THE INVENTION: DEVICE FOR VEHICLE AIR SPRING, ACCESS CAP, FORK AND VEHICLE CONTAINING SUCH A DEVICE

[0003] TECHNICAL FIELD OF THE INVENTION

[0004] The present invention relates to a device for a vehicle air spring, an access plug, a fork, and a vehicle incorporating such a device. In particular, the present invention relates to the field of shock absorbers for bicycles or motorcycles.

[0005] STATE OF THE ART

[0006] Bicycles and motorcycles are equipped with shock absorbers located in the fork attached to the front wheel. The damping is usually produced by a spring, an air spring, or a hydraulic spring.

[0007] Air springs consist of a piston moving within a cylinder, with the piston and cylinder forming a compression chamber. This compression chamber is closed by an access plug. The access plug allows for maintenance and adjustments to adapt the spring's capacity to the terrain and / or the rider of the bicycle or motorcycle.

[0008] Pneumatic springs are also called "air springs." The spring force corresponds to the air pressure. This pressure depends on the amount of air relative to the chamber volume. The more the spring is compressed, the stiffer it becomes. For example, the pressure doubles when the compression is doubled. It is therefore a progressive spring, as its stiffening increases exponentially at the end of its travel. Such a spring can be defined by a so-called "progression curve," as shown in Figure 1.

[0009] The curve of an air spring is sometimes criticized for its lack of support in the so-called "travel" zone. This is why one or more hard, waterproof plastic shims are added to reduce the volume of the compression chamber. These shims are also called "tokens." To add or remove shims, the assembly plug has an assembly relief, and the shim has a corresponding relief on one side and the same relief as the access plug on the other. Thus, a shim can be attached to the access plug, and additional shims can be attached to each other to form a tower.

[0010] The more spacers there are, the more the air volume in the compression chamber is reduced, resulting in a fork that stiffens up more quickly.

[0011] If the number of shims is correct, the user will feel better support from the fork at mid-stroke.

[0012] The air spring is often paired with a negative spring, which can be made of steel or a negative air chamber. This negative spring increases sensitivity to small impacts. Because the air spring produces more friction, its activation threshold is higher than that of a coil spring; hence the use of the negative spring to counteract this effect.

[0013] However, the user is limited to a choice of progression curves equal to the maximum number of wedges the user can add, plus one, depending on the number of wedges added and must therefore adapt to the choices offered to him.

[0014] Such progression curves are represented schematically in Figure 1, where the x-axis represents the piston stroke and the y-axis represents the force (in Newtons) required to achieve this stroke at equivalent initial air pressure.

[0015] Curve 11 represents an air spring curve without a shim, curve 12 represents an air spring with one shim, curve 13 represents an air spring with two shims and curve 14 represents an air spring with three shims.

[0016] SUMMARY OF THE INVENTION

[0017] The present invention aims to remedy all or part of these drawbacks.

[0018] It features a foam elastomer shim holder that is directly attached to the cap. Removing, replacing, adding, or deleting the shims is therefore easy and won't damage the piston cylinder. Since the shims' dimensions and materials are adaptable, an infinite number of progression curves are possible, making it suitable for any terrain and user.

[0019] BENEFITS PROVIDED

[0020] Accordingly, in a first aspect, the present invention relates to a device for a vehicle air spring, the air spring comprising a piston moving along an axis in a cylinder, and an access plug for the cylinder placed on the axis of movement of the piston, the device comprising:

[0021] - at least one removable foam shim configured to absorb vibrations and / or provide filtration, comprising an assembly relief with at least one reinforcement, the assembly relief passing completely through the shim,

[0022] - a support comprising a means of attachment to the access plug and / or the cylinder and at least one armature, at least one armature being configured to assemble to the relief and to pass through the assembly relief of at least one said removable wedge and configured to receive at least one said removable wedge.

[0023] Thanks to these features, the foam shims are directly attached to the access plug. Therefore, by removing the access plug, it is easy to replace or remove the shims.

[0024] The shims, which vary in material, size, and / or shape, allow the air spring's behavior to be adjusted according to the user's needs and / or the terrain, particularly in the case of bicycle or motorcycle forks. Furthermore, several elastomer foam shims of different densities or dimensions can be positioned on the frame, enabling very precise adjustment of the air spring's behavior based on the terrain and the vehicle's rider. Since the dimensions, densities, and materials of the shims are adaptable, an infinite number of progression curves can be achieved, thus adapting to any terrain and rider.

[0025] With waterproof plastic wedges, the user feels significant hardness during an impact or shock due to the roughness of the terrain, whereas the present invention allows for a good grip on the terrain while limiting the effect of the impact.

[0026] In embodiments, the device of the present invention comprises at least two wedges assembled with said at least one armature, the assembly relief of each wedge being traversed by said at least one armature.

[0027] Thanks to these features, the foam slows the airflow passing through it, improving the spring's progressive action. In other words, the airflow is filtered and the wedge deforms, allowing it to absorb shocks.

[0028] In some embodiments, at least one armature is traversed by an orifice with an axis parallel to the axis of movement of the piston.

[0029] Thanks to these arrangements, it is possible to inject air into the piston through the access plug and the armature to adjust the capabilities of the pneumatic spring.

[0030] In some embodiments, at least one reinforcement has a truncated right cylinder shape with a predefined guide curve, the assembly relief of each removable wedge has a corresponding truncated right cylinder shape with a predefined guide curve.

[0031] Thanks to these arrangements, the wedges can be assembled by sliding them around the frame.

[0032] In embodiments, the device of the present invention further comprises at least one orifice passing through at least one armature perpendicular to the axis of movement of the piston.

[0033] Thanks to these provisions, the performance of the device is improved.

[0034] In some embodiments, at least one orifice is an oblong hole.

[0035] Thanks to these provisions, the performance of the device is improved.

[0036] In some embodiments, at least one armature with a dimension along the axis of piston movement is greater than the dimension of at least one shim along the axis of piston movement.

[0037] Thanks to these arrangements, several wedges can be placed on the same reinforcement. In some embodiments, a reinforcement is a rod with a circular cross-section.

[0038] Thanks to these arrangements, the wedges can easily be put on or taken off the stem.

[0039] In some embodiments, the device of the present invention comprises a plurality of armatures positioned on a periphery of the fastening means.

[0040] Thanks to these arrangements, the wedges are placed between the reinforcement bars. In some embodiments, at least one reinforcement bar includes a means for locking each removable wedge against at least one other reinforcement bar, each removable wedge being locked along the length of at least one reinforcement bar between the locking means and the fixing means.

[0041] Thanks to these arrangements, the wedges remain positioned on the frame, regardless of the shocks received by the pneumatic spring.

[0042] In some embodiments, at least one armature has at least one concave relief.

[0043] Thanks to these arrangements, the passage of air is facilitated during the expansion and compression phases of the pneumatic spring.

[0044] In some embodiments, the fastening means has a truncated straight cylinder shape corresponding to the cylinder of the pneumatic spring.

[0045] Thanks to these arrangements, the support is inserted into the cylinder.

[0046] In some embodiments, the fastening means is configured to form a sliding connection with the access plug, with the axis perpendicular to the axis of movement of the piston.

[0047] Thanks to these provisions, in the event of shocks to the air spring, particularly if it is integrated into a fork or shock absorber, the support is locked in position on the access plug once the support is assembled to the access plug and inserted into the cylinder.

[0048] In some embodiments, at least one shim has a washer shape and has at least one peripheral groove along an axis parallel to the axis of movement of the piston.

[0049] Thanks to these arrangements, air can easily circulate around the wedges in the compression chamber.

[0050] In some embodiments, the fastening means is configured to assemble with a relief of the piston.

[0051] Thanks to these provisions, the device which is the subject of the present invention can be assembled directly into the body of the piston.

[0052] According to a second aspect, the present invention relates to an access plug for a vehicle air spring, the air spring comprising a piston moving along an axis in a cylinder, the access plug to the cylinder being placed on the axis of movement of the piston, and comprising:

[0053] - at least one removable foam shim configured to absorb vibrations and / or provide filtration, featuring an assembly relief with at least one reinforcement, the assembly relief passing completely through the shim,

[0054] - a support comprising at least one reinforcement, the at least one reinforcement being shaped to correspond to the assembly relief of at least one said removable wedge and configured to pass through the assembly relief of at least one said removable wedge and configured to receive at least one said removable wedge. The purposes, advantages, and specific characteristics of the access plug that is the subject of the present invention being similar to those of the device that is the subject of the present invention, they are not repeated here.

[0055] According to a third aspect, the present invention relates to a vehicle fork comprising an air spring, the air spring comprising a piston moving along an axis in a cylinder and an access plug to the cylinder placed in the axis of movement of the piston and at least one device of the present invention or an access plug of the present invention.

[0056] The purposes, advantages and special characteristics of the fork which is the subject of the present invention being similar to those of the device which is the subject of the present invention, they are not recalled here.

[0057] According to a fourth aspect, the present invention relates to a vehicle comprising a fork having an air spring, the air spring having a piston moving along an axis in a cylinder and an access plug to the cylinder placed in the axis of movement of the piston and at least one device of the present invention or an access plug of the present invention.

[0058] Since the aims, advantages and special characteristics of the vehicle that is the subject of the present invention are similar to those of the device that is the subject of the present invention, they are not recalled here.

[0059] BRIEF DESCRIPTION OF THE FIGURES

[0060] Other advantages, purposes and special features of the invention will become apparent from the following non-limiting description of at least one particular embodiment of the device that is the subject of the present invention, with reference to the accompanying drawings, in which:

[0061] - Figure 1 schematically represents an example of the progression curves of a prior art device,

[0062] - Figure 2 schematically and in cross-section represents a first embodiment of a device that is the subject of the present invention,

[0063] - Figure 3 schematically represents, from a bottom view, the first embodiment of a device that is the subject of the present invention,

[0064] - Figure 4 schematically represents, in front view, different embodiments of a support for a device that is the subject of the present invention,

[0065] - Figure 5 schematically represents, from a bottom view, two wedge profiles of the device that is the subject of the present invention,

[0066] - Figure 6 schematically represents, in front view, a pneumatic spring comprising the device that is the subject of the present invention, and

[0067] - Figure 7 schematically represents, in front view, a fork incorporating the device that is the subject of the present invention; - Figure 8 schematically represents, in front view, a vehicle incorporating the device that is the subject of the present invention.

[0068] - Figure 9 schematically represents, in front view, different embodiments of a support for a device that is the subject of the present invention,

[0069] - Figure 10 schematically represents, in side view, a vehicle shock absorber equipped with an embodiment of the device that is the subject of the present invention,

[0070] Figure 11 represents a comparative curve showing the sensitivity of three shims of different densities mounted on a device of the present invention compared to a prior art device.

[0071] - Figure 12 represents a second curve showing the sensitivity of three density shims mounted on a device of the present invention compared to a prior art device,

[0072] - Figure 13 represents a third comparative curve between a device the object of the present invention equipped with the same wedges, but in which one frame does not have orifices, another is equipped with circular orifices and

[0073] - Figure 14 represents a third comparative curve between a device of the present invention equipped with the same wedges, but in which one armature is equipped with circular orifices, another is equipped with oblong holes.

[0074] DESCRIPTION OF IMPLEMENTATION METHODS

[0075] The present description is given by way of non-limiting attribution, each feature of an embodiment being able to be advantageously combined with any other feature of any other embodiment.

[0076] The expression "and / or", as used in this document and in the claims, shall be understood as meaning "one or the other or both" of the elements thus joined, that is, elements that are present conjunctively in some cases and disjunctively in others. Multiple elements listed with "and / or" shall be interpreted in the same way, that is, "one or more" of the elements thus joined. Other elements may also be present, other than the elements specifically identified by the "and / or" clause, whether or not they are related to those specifically identified elements.Thus, by way of non-limiting example, a reference to "A and / or B", when used in conjunction with an open language such as "including", may refer, in one embodiment, to A only (possibly including elements other than B); in another embodiment, to B only (possibly including elements other than A); in yet another embodiment, to A and B (possibly including other elements); etc.

[0077] As used in this description, the expression "at least one," when referring to a list of one or more items, should be understood as meaning at least one item chosen from one or more items in the list of items, but not necessarily including at least one of each item specifically listed in the list of items and not excluding any combination of items in the list of items. This definition also allows for the optional presence of items other than those specifically identified in the list of items to which the expression "at least one" refers, whether or not they are related to those specifically identified items.Thus, by way of non-limiting example, "at least one of A and B" (or, equivalently, "at least one of A or B", or, equivalently, "at least one of A and / or B") may refer, in one embodiment, to at least one, possibly including more than one, A, without B present (and possibly including elements other than B); in another embodiment, to at least one, possibly including more than one, B, without A present (and possibly including elements other than A); in yet another embodiment, to at least one, possibly including more than one, A, and at least one, possibly including more than one, B (and possibly including other elements); etc.

[0078] In the description below, all transitive expressions such as "comprising", "including", "carrying", "having", "containing", "implying", "holding", "composed of", and others, should be understood as open, that is, as meaning "including, but not limited to". Only the transitive expressions "consisting of" and "consisting essentially of" should be understood as closed or semi-closed transitive expressions, respectively.

[0079] Figures 2 and 3 show a first embodiment of a device 20, the object of the present invention, for a pneumatic spring 60 of a vehicle 80.

[0080] Figure 6 shows an embodiment of an air spring 60, and Figure 10 shows an embodiment of a shock absorber 67. The shock absorber or air spring 60 comprises a piston 62 moving along an axis 21 within a cylinder 61, and an access plug 63 for the cylinder 61 located on the axis of movement 21 of the piston 62. Air springs 60 are well known to those skilled in the art. The piston 62 and the cylinder 61 define a space called the "compression chamber" 66, into which pressurized air is inserted. The air pressure when the piston is at bottom dead center defines the elastic characteristics of the spring 60.

[0081] It is known to those skilled in the art, in the field of bicycle and motorcycle forks, to air springs and shock absorbers having a piston defining two compression chambers, one called "positive" and the other "negative". Preferably, device 20 is placed in the positive compression chamber, but can also be placed in the negative compression chamber.

[0082] It should be noted from the outset that the figures are not to scale.

[0083] Device 20 includes:

[0084] - at least one removable foam shim, 28, 30, 32, 34, configured to absorb vibrations and / or provide filtration, comprising an assembly relief, 29, 31, 33, 35, with at least one reinforcement 25,

[0085] - a support 22 comprising a means of fixing, 23 and 24, to the access plug 63 and at least one reinforcement 25, at least one reinforcement 25 being of shape 27 corresponding to the assembly relief, 29, 31, 33, 35, of at least one said wedge, 28, 30, 32, 34, removable and configured to receive at least one said removable wedge.

[0086] In the embodiment shown in Figure 2, the assembly relief, 29, 31, 33, 35, of each wedge, 28, 30, 32, 34, is a truncated right cylinder with a circular directrix. Each wedge, 28, 30, 32, 34, has a truncated right cylinder shape with a circular directrix concentric to the directrix of the assembly relief, 29, 31, 33, or 35, and a diameter greater than the diameter of the directrix of the assembly relief, 29, 31, 33, or 35. Each wedge, 28, 30, 32, 34, therefore has a washer shape. Thus, a peripheral shape and an internal shape corresponding to the assembly relief can be defined.

[0087] It is worth recalling here that a framework is an element or an assembly of various elements that serve to support the different parts of a whole.

[0088] Axis 21 can also be considered as an axis of symmetry for the wedges, the reinforcement and the means of fixing, or as an axis of revolution for these same elements.

[0089] This embodiment is shown by way of example, and other types of generators can be used to represent the peripheral and internal shapes, for example, a square, a polygon, or an ellipse, or any other shape known to a person skilled in the art. The peripheral and internal shapes may be different. Preferably, the peripheral shape circumscribes the internal shape.

[0090] Preferably, the center of gravity of the guide curve of the assembly relief, 29, 31, 33, 35, and of the peripheral shape are aligned. When the device 20 is assembled to an access plug 63 and inserted into the compression chamber 66 of the air spring 60, said centers of gravity are on the axis of displacement 21 of the piston 62.

[0091] In embodiments (not shown), the assembly relief, 29, 31, 33, 35, comprises a plurality of truncated straight cylinders, preferably parallel, each truncated cylinder corresponding to an armature.

[0092] In embodiments shown in Figure 9, the assembly relief, 29, 31, 33, 35, comprises a plurality of truncated straight cylinders, forming an intersection with the peripheral form, preferably parallel, each truncated cylinder corresponding to an armature.

[0093] In other words, the shims can be assembled on a single central armature, or on several armatures, for example, peripheral ones. A peripheral armature is a armature placed against the cylinder of the compression chamber. The shims can also be assembled with a plurality of armatures placed between the peripheral position and the axis of movement of the piston 21.

[0094] In other embodiments (not shown), the reinforcement or a set of reinforcements forms a cage with a perforated, truncated cylinder shape, complete or partial, with a circular base. In such embodiments, the reinforcement set may be a set of reinforcements arranged in an arc around the periphery of the wedges. Figure 5 shows two profiles, 50 and 51, different from wedges 28. Profile 50 corresponds to the wedge described above opposite Figure 2. Profile 51 has at least one groove 52 on its peripheral shape. Each groove 52 may be of any profile known to those skilled in the art, for example, square, rectangular, arc-shaped, or polygonal. Each groove 52 has its axis parallel to the axis of movement of the piston 21. In other words, each groove 52 extends along an axis parallel to the axis of movement of the piston 21, the profile corresponding to an empty space along said axis.

[0095] In other embodiments, each groove can follow a helical curve.

[0096] Figure 5 shows that the profile 51 has four grooves 52 equidistant from each other. More generally, regardless of the number of grooves in a wedge, 28, 30, 32, 34, the grooves are distributed around the periphery of the wedge, 28, 30, 32, 34.

[0097] In the embodiment shown in Figures 2 and 3, each shim, 28, 30, 32, 34, can have a different density, as indicated by the different dashed lines used. Furthermore, in the embodiment shown in Figures 2 and 3, shims 28, 30, and 32 have the same dimension along axis 21, hereinafter referred to as "thickness," with shim 34 having a thickness less than that of one of the shims, 28, 30, or 32.

[0098] Preferably, the material of each removable wedge is a cellular or semi-cellular elastomeric foam. The density of said foam can be adapted.

[0099] In preferred embodiments:

[0100] - each shim, 28, 30, 32 and 34, can have a thickness chosen from one of the following values: 12.5 mm, 25 mm, 37.5 mm and 50 mm,

[0101] - each wedge, 28, 30, 32 and 34, is made of elastomer foam with a compressive strength between 14 and 3640 kPa, preferably chosen from the following values: 14, 22, 63, 82, 170, 330, 620, 840, 1050, 1241, 3640.

[0102] Preferably, each wedge, 28, 30, 32 and 34, is made of elastomeric foam from the brand "Regufoam"®.

[0103] Of course, other thicknesses and other compressive strengths can also be used.

[0104] In embodiments, washers of similar shape to the shapes of the shims, 28, 30, 32 and 34, can be inserted between at least two shims.

[0105] Preferably, the reinforcement 25 has a dimension along the axis 21. The number of spacers, 28, 30, 32 and 34, that the reinforcement can receive is such that the sum of the thicknesses of the spacers, 28, 30, 32 and 34 is less than the dimension of the reinforcement along the axis 21.

[0106] Preferably, the dimension of the armature 25 along the axis 21 is such that the distance between the distal end of the armature 25 and the piston is always strictly greater than zero millimeters. In other words, the armature 25 and the piston do not come into contact.

[0107] The device 20 includes the reinforcement 25. The reinforcement 25 has a truncated cylindrical shape 27 with a predefined direction curve corresponding to the internal shape of each wedge, 39, 30, 31, 33, 28, 30, 32, 34. In Figures 2 and 3, the direction curve is a circle. However, similarly to what was described above concerning the wedges, the direction curve can be of any shape known to those skilled in the art. Furthermore, the device 20 can include several reinforcements. In these embodiments, the reinforcements are preferably parallel.

[0108] In embodiments shown in Figure 9, the device 20 comprises several supports, for example, peripheral supports 96. A peripheral support 96 is a support placed against the cylinder of the compression chamber. The shims can also be assembled with a plurality of supports placed between the peripheral position and the axis of movement of the piston 21. As shown on the right of Figure 9, the peripheral supports 96 have, in cross-section, a circular arc profile. This figure shows four peripheral supports 96 equally spaced around the periphery of the support 22 and extending along the axis 21. Shims 28 are placed between the peripheral supports 96.

[0109] In other embodiments (not shown), the reinforcement or a set of reinforcements forms a perforated cage in the shape of a truncated cylinder, complete or partial, with a circular base. Such a cage may be made of micro-perforated polyvinyl chloride (PVC), for example. In such embodiments, the reinforcement set may be a set of reinforcements arranged in an arc around the periphery of the wedges.

[0110] In some embodiments, the frame has a helical shape with axis 21, the wedges screwing into and / or around this shape.

[0111] Preferably, the reinforcement 25 has an axis passing through the center of gravity of the directrix curve. The axis of the reinforcement 25 is preferably coincident with the axis 21.

[0112] In preferred embodiments, the armature 25 is traversed by an orifice 26 with an axis parallel to the axis 21 of movement of the piston 62. Such an orifice allows, when the spring is pressurized, for air to be injected through the access plug 63 into the compression chamber 66. The orifice 26 is a circular bore, with its axis coinciding with the axis 21, for example.

[0113] In some embodiments, the orifice 26 has a diameter corresponding to the diameter of a hydraulic rod known to the person in the suspension trade.

[0114] In other embodiments, the wedges and / or the support 22 may include machining, drilling or any other means of circulating air from a pump.

[0115] In preferred embodiments, the frame 25 includes a locking means, 36 and 37, for each wedge, 28, 30, 32, 34, removable against the frame 25, each wedge, 28, 30, 32, 34, removable being locked along the frame 25 between the locking means, 36 and 37, and the fixing means 22.

[0116] In Figures 2 and 3, such an optional locking means is shown in the form of a groove 36 on the frame, into which a circlip 37 is fitted. These embodiments facilitate the removal and installation of this fastening means to add or remove one or more shims. Furthermore, this helps to limit the weight of the added parts. In some embodiments, for example as shown on the left of Figure 9, the locking means 92 is a bead or shoulder extending from the distal end of the frame 25. Each shim 28 is then fitted onto the rod 25 and deforms to pass around the bead or shoulder 92.

[0117] The locking means is configured to limit the translational movement of each wedge, 28, 30, 32 or 34 to the dimension of the reinforcement 25 along the axis 21.

[0118] In some variations, the locking means is a bolt formed by means of a thread on the end of the reinforcement 25 furthest from the fastening means 22, called the "distal end," and a nut. In other embodiments, the locking means is a pin assembled in a corresponding hole perpendicular to the axis 21, formed in the reinforcement 25. In other embodiments, the locking means has grooves on the reinforcement 25, flaring out towards the distal end of the reinforcement 25.

[0119] In other embodiments, the frame 25 includes a locking means for each shim. For example, the frame 25 may include a hole and a pin installed at regular intervals corresponding to the thickness of a shim.

[0120] In embodiments in which device 25 includes a set of reinforcements, at least one reinforcement may include a locking means or at least two reinforcements may cooperate with a locking means to prevent the translation of the wedges along axis 21.

[0121] In some embodiments, the locking means may be a tolerance interval between the reinforcement 25 and the assembly relief 29, 31, 33, 35, configured so that the fit is with interference, otherwise called a fit with interference.

[0122] In general, the locking means 25 can be any means configured to prevent each wedge, 28, 30, 32, 34, from moving in translation along the axis 21. The locking means can therefore include any assembly method, shape, geometry or inclination configured to prevent this movement.

[0123] In embodiments shown in Figure 4, the frame 25 has at least one concave relief, 41, 42, 43, 44, 45 or 47, configured for the passage of air between at least one wedge, 28, 30, 32, 34 and the frame 25. Figure 4 shows two embodiments, 40 and 46, of supports which are the subject of the present invention.

[0124] In embodiment 40, shown on the left of Figure 4, the reinforcement has several openings, 41, 42, and 43, passing through the reinforcement along an axis perpendicular to axis 21. Although embodiment 40 shows three openings, the reinforcement could have more or fewer openings. Preferably, the openings, 41, 42, and 43, are equidistant from each other. In addition, the reinforcement has several openings, 44 and 45, passing through the reinforcement along an axis perpendicular to axis 21 and perpendicular to the openings, 41, 42, and 43.

[0125] In embodiment 46, shown on the right of figure 4, the reinforcement is traversed by a helical groove 47 with axis 21. Other examples of concave reliefs are, for example, a set of channels in fluidic communication, for example forming a cross in top view or a perforated surface.

[0126] In the embodiments shown on the left of Figure 9, the orifices 91 are oblong holes. Preferably, the dimension of the oblong hole along the axis 21 is greater than or equal to half the dimension of a shim 28 along the axis 21. Preferably, the center of gravity of each oblong hole 91 corresponds to the center of gravity of each shim 28 of predetermined dimension along the axis 21.

[0127] Of course, any type of orifice or channel known to a person in the trade can be used.

[0128] The fastening means 22 is assembled to the frame 25. Preferably, the fastening means 22 has a truncated right-hand cylinder shape corresponding to the cylinder of the pneumatic spring. For example, the fastening means 22 has a truncated right-hand cylinder shape with a circular direction concentric to the direction of the frame 25.

[0129] This embodiment is shown as an example and other types of generators can be used to represent the peripheral shape of the fastening means, for example, a polygon, or an ellipse.

[0130] The fastening means 22 is any fastening means known to those skilled in the art that prevents the device 20 from translating along the axis 21 while allowing the access plug 63 to move freely with the cylinder 61. For example, the fastening means 22 could be a thread 93 corresponding to a tapped hole, one on the device 22 and the other on the access plug 63, as shown on the left of Figure 9, for example. Alternatively, the fastening means 22 could be a snap-on or clip-on means with a corresponding shape on the access plug 63, such as the gasket 97 shown on the right of Figure 9, for example.

[0131] In embodiments in which the frame 25 has an orifice 26, the fastening means 22 may have a corresponding orifice 38 connecting the orifice 26 to the periphery of the fastening means 22. In the embodiment shown, such an orifice 38 is positioned in the groove 23 and has a circular arc cross-section.

[0132] Preferably, when the device 20 is assembled to an access plug 63 and inserted into the compression chamber 66 of the air spring 60, the center of gravity of the direction curve is on the axis of displacement 21 of the piston 62.

[0133] Preferably, the fastening means 22 is configured to form a sliding connection with an axis perpendicular to the axis of movement 21 of the piston 61 with the access plug 63.

[0134] Specifically, Figures 2 and 3 show a T-shaped groove, 23 and 24, passing through the fastening means 22 to the axis 21. Preferably, the groove 23 and 24 opens into a circular cavity with a T-shaped cross-section. The cavity has dimensions larger than those of the groove. This shape allows:

[0135] - that it is assembled to a stud 65 present on the access plug 63 is known to a person skilled in the art,

[0136] - to create friction between the stud 65 and the groove, 23 and 24, but to leave the groove free to rotate in the cavity.

[0137] The fastening means 22 and the frame 25 are preferably machined from a single piece. Such a piece is made of steel, plastic or aluminum, for example.

[0138] As can be seen from Figures 2, 3 and 6, the user performs the following steps to assemble the device 20 to a pneumatic spring 60:

[0139] - selection of at least one shim, 28, 30, 32, 34, defined by its material and thickness,

[0140] - placement of each wedge, 28, 30, 32, 34, chosen on the frame 25 by fitting it from the distal end to the fixing means 22,

[0141] - positioning of a circlip 37 in the groove 36,

[0142] - sliding of the stud 65 of the access plug 63 in the groove 23 and 24 until it reaches the cavity.

[0143] More generally, the positioning step can be replaced by a locking step using the locking means(s). And, the sliding step can be replaced by a step of attaching the device to the access plug 63, depending on the attachment means 22.

[0144] The plug 63, fitted with the device 20, is then assembled in the pneumatic spring in a manner known to those skilled in the art, and the adjustments known to those skilled in the art are made. For example, as can be seen in Figure 6, the plug has a thread 64 corresponding to a tapped hole in the cylinder 61.

[0145] To replace, add or remove a shim, 28, 30, 32, and 34, the user removes the circlip 37 from the groove 36, performs the desired action and replaces the circlip 37 in the groove 36. More generally, the user removes the locking means, performs the desired action and then replaces the locking means.

[0146] In some embodiments, the piston cylinder 62 has a groove configured to delimit two chambers. In such embodiments, and as shown on the right of Figure 9, the fastening means 22 may include a seal 97 configured to be assembled to the groove in the piston cylinder 62.

[0147] In such embodiments, the frame, 25 or 96, may include an attachment hole for a hook to dislodge the device of the present invention, 20, 40, 46, 90 or 95.

[0148] In such embodiments, the fastening means 22 can be a washer 22.

[0149] Figure 6 shows, from the plug 63 to the piston 62, along the axis 21 of piston movement:

[0150] - the plug 63, fitted with a threaded shaft, 64 having a stud 65 at its end,

[0151] - the device 20, comprising the fixing means 22, the stud 65 being assembled in the groove, 23 and 24, then the frame 25 surrounded by two wedges, the circlip 37 and the groove are not shown, - around the threaded part 64 of the plug 63 and the device 20 is the cylinder 61, ending with the piston 62.

[0152] In some embodiments (not shown), the device 20 is integrated into the access plug 63; in other words, the device 20 and the access plug 63 form a single piece. The device 20 therefore does not have a means for attaching it to the plug. In other words, the access plug 63 comprises:

[0153] - at least one wedge, 28, 30, 32, 34, removable elastomeric foam having an assembly relief, 29, 31, 33, 35, with a reinforcement 25,

[0154] - a support, 22, 25, comprising the frame 25, the frame being of a shape corresponding 27 to the assembly relief of at least one said removable wedge and configured to receive at least one said removable wedge.

[0155] Figure 10 shows a device 20, the subject of the present invention, fixed in a chamber of a shock absorber. The fastening means can be configured to assemble to a pre-existing relief of the shock absorber 67, or around the piston rod. In some embodiments, the fastening means of the device is configured to deform under the action of an external force to be positioned in the chamber 66. Preferably, the armature of the device 20 is a peripheral armature.

[0156] Figure 7 shows a bicycle fork 70 for a bicycle 80 comprising an air spring 60, the air spring 60 having a piston 62 moving about an axis in a cylinder 61 and an access plug 63 to the cylinder 61 located on the axis of movement of the piston 62, and at least one device 20 of the present invention. The fork 70, without the device 20, is known to those skilled in the art.

[0157] Figure 8 shows a bicycle 80 comprising a fork 70 comprising an air spring 60, the air spring 60 comprising a piston 62 moving along an axis in a cylinder 61 and an access plug 63 to the cylinder 61 placed in the axis of movement of the piston 62 and at least one device 20 of the present invention.

[0158] In the description above, it is noted that the embodiments of the fastening means 22 described opposite Figures 2, 4, and 9 can be associated with any embodiment of the reinforcement, 25 or 96, described opposite these same figures. In other words, elements shown in the same figure are not functionally linked, and an embodiment of a fastening means described opposite one of these figures can be associated with an embodiment of a reinforcement in another of these figures.

[0159] Figures 11 to 15 represent curves obtained from comparative tests carried out on a test bench. Figures 11 and 12 represent curves, on an orthonormal coordinate system, with the displacement of the piston rod in millimeters on the x-axis and the force applied to the pneumatic spring on the y-axis.

[0160] The tests were conducted on a LABA 7® AMA® suspension test bench. The tests were performed comparatively on the same shock absorber, with the same initial air pressure, the same air chamber volume, and identical sag. Sag refers to the static compression of the fork with the rider on the bicycle. These parameters were intentionally kept constant so that any differences observed in the curves would be solely attributable to the specific unit being tested.

[0161] Figure 11 shows four curves, 101, 102, 103, and 104, created using a different number of RockShox® shims, also called "tokens," inserted into a piston chamber. Curve 101 represents one token added to the piston chamber, curve 102 represents two tokens added to the piston chamber, curve 103 represents three tokens added to the piston chamber, and curve 104 represents four tokens added to the piston chamber.

[0162] Curves 105 and 106 show four shims of the same density mounted on a device of the present invention, in which the frame 25 has no openings. To create curve 105, four foam shims with a density of 0.629 kg / mm³ were used; to create curve 106, four foam shims with a density of 0.621 kg / mm³ were used.

[0163] As can be seen in Figure 11, with the use of tokens, the curves are regularly spaced, thus leaving no possibility of adaptation for the user. Conversely, curves 105 and 106 show different behavior of the shims depending on the density of the foam chosen, thus giving the user, through the number of shims, the density, and the dimensions of the foam chosen, a wide range of choices to obtain the desired behavior in the damping chamber.

[0164] In Figure 12, curves 107 and 109 show four shims of the same density mounted on a device of the present invention, in which the frame 25 has no openings. To create curve 107, four foam shims with a density of 1.113 kg / mm³ were used; to create curve 109, four foam shims with a density of 1.149 kg / mm³ were used. Figure 12 also shows tokens placed on a fork of the registered trademark Sid.

[0165] Regarding Figures 11 and 12, comparing foam inserts to rigid tokens, tests show that with the same number of inserts, identical air volume, air pressure, and sag, simply changing the foam density alters the progression curve of the air spring. The air chamber volume remains unchanged; only the mechanical properties of the foam vary.

[0166] The foam acts both through its deformation capacity and by filtering the airflow. This combination allows for a more gradual increase in force and a more linear behavior of the air spring.

[0167] Conversely, stiff tokens function solely by reducing air volume. At the same air pressure, each token added alters the sag, making the curve increasingly exponential, with a rapid stiffening at the end of the travel. This type of adjustment severely limits the possibilities for intermediate settings and modifies not just one parameter, but several parameters of the spring's behavior simultaneously.

[0168] The curves thus show that, unlike tokens, foams offer a great deal of adjustability: with the same number of cleats, it is possible to modify the progression curve simply by varying the foam density, without changing the air volume or the base setting. By combining different densities and cleat thicknesses (for example, 12.5 mm, 25 mm, etc.), it is possible to cover a very wide range of performance characteristics continuously.

[0169] Figures 13 and 14 represent curves, on an orthonormal coordinate system, with the x-axis representing the piston rod's displacement velocity in millimeters per second and the y-axis representing the force applied to the pneumatic spring. Figures 13 and 15 show two different armatures with the same shims being tested.

[0170] Figure 13 shows the compression and rebound performance of the same shock absorber with identical shims but different armatures. Curve 110 illustrates the performance of armature 25 in its solid rod form. Curve 111 shows armature 25 with regularly spaced circular holes. As can be seen, curve 111 exhibits greater sensitivity than curve 110, demonstrating the particular advantage of the holes.

[0171] Figure 14 shows the compression and rebound performance of the same shock absorber with identical shims but different armatures. Curve 112 shows an armature 25 with regularly spaced circular holes. Curve 113 shows an armature 25 with regularly spaced oblong holes. Note that the drilled area of ​​the rods used to create these curves is the same for both armatures. In other words, the same amount of material was removed from each of the armatures used in the test.

[0172] As can be seen, curve 112 shows greater sensitivity than curve 113 in both compression and rebound, demonstrating the additional benefit of oblong holes.

[0173] Regarding the tests carried out with different rods (solid rod, rod drilled with circular holes, rod drilled with oblong holes), shown in Figures 13 and 14, the tests were performed in exactly the same way, with the same shims, the same air volume, the same air pressure, and the same sag. The only variable modified was the geometry of the rod and the shape of the air passages.

[0174] The curves clearly show that the way air flows through the rod directly influences the behavior of the air spring. With identical shims, a solid rod exhibits less sensitivity for the same travel speed, resulting in a loss of sensitivity, particularly under low loads.

[0175] For an equivalent perforated surface area, the shape of the shaft's holes (circular or oblong) further modifies the spring's response. The curves notably show that oblong holes provide superior sensitivity, particularly at low speeds, in both compression and rebound. This demonstrates that it is not the amount of material removed that influences the spring's behavior, but rather the geometry of the air passages and the dynamics of airflow within the shaft. The differences observed in the curves are very clear in real-world use, especially in terms of sensitivity, comfort over small bumps, and travel control, thus confirming the correlation between bench measurements and real-world riding experience.

[0176] Finally, the adjustment of the behavior of the air spring can be considered almost infinite, not only thanks to the choice of the number, density and thickness of the foam shims, but also thanks to the geometry of the rod and the shape of the vents, which constitute a second lever for adjusting the dynamic behavior of the spring.

Claims

DEMANDS 1. Device (20, 90, 95) for a vehicle (80) air spring (60), the air spring comprising a piston (62) moving along an axis (21) in a cylinder (61) and an access plug (63) to the cylinder located on the axis of movement of the piston, the device being characterized in that it comprises: - at least one removable foam shim (28, 30, 32, 34) configured to absorb vibrations and / or provide filtration, comprising an assembly relief (29, 31, 33, 35) with at least one reinforcement (25, 96), the assembly relief passing through the shim from one side to the other, - a support (22, 25) comprising a means of attachment (22) to the access plug and / or the cylinder and at least one armature (25, 96), at least one armature being configured to pass through the assembly relief of at least one said removable wedge and configured to receive at least one said removable wedge.

2. Device (20, 90, 95) according to claim 1, comprising at least two wedges (28, 30, 32, 34) assembled with said at least one reinforcement (25, 96), the assembly relief (29, 31, 33, 35) of each wedge being traversed by said at least one reinforcement 3. Device (20, 90) according to any one of claims 1 or 2, in which at least one armature (25) is traversed by an orifice (26) with an axis parallel to the axis (21) of displacement of the piston (62).

4. Device (20, 90) according to any one of claims 1 to 3, wherein at least one armature (25) has a truncated right cylinder shape with predefined guide curve, the assembly relief (29, 31, 33, 35) of each removable wedge (28, 30, 32, 34) has a corresponding truncated right cylinder shape with predefined guide curve.

5. Device (20, 90) according to any one of claims 1 to 4, further comprising at least one orifice (41, 42, 43, 44, 45, 91) passing through at least one armature (25) perpendicular to the axis (21) of piston movement.

6. Device (90) according to claim 5, wherein at least one orifice (91) is an oblong hole.

7. Device (20, 90, 95) according to any one of claims 1 to 6, wherein at least one armature (25, 96) of dimension along the axis of displacement (21) of the piston (62) is greater than the dimension of at least one shim (28, 30, 32, 34) along the axis of displacement of the piston.

8. Device (20, 90) according to any one of claims 1 to 7, wherein an armature is a rod of circular cross-section.

9. Device (95) according to any one of claims 1 to 7, comprising a plurality of armatures (96) positioned on a periphery of the fastening means (22).

10. Device (20, 90) according to any one of claims 1 to 9, wherein at least one frame (25) comprises a locking means (36, 37) for each removable wedge (28, 30, 32, 34) against at least one frame, each removable wedge being locked along the at least one frame between the locking means and the fixing means (22).

11. Device (20) according to any one of claims 1 to 10, wherein at least one armature (25) has at least one concave relief (47).

12. Device (20, 90, 95) according to any one of claims 1 to 11, wherein the fastening means (22) has a truncated straight cylinder shape corresponding to the cylinder (61) of the pneumatic spring (60).

13. Device (20) according to any one of claims 1 to 12, wherein the fastening means (22) is configured to form a sliding connection with axis perpendicular to the axis (21) of movement of the piston (62) with the access plug (63).

14. Device (20) according to any one of claims 1 to 13, wherein at least one shim (28, 30, 32, 34) has a washer shape and has at least one peripheral groove (52) along an axis parallel to the axis (21) of movement of the piston (62).

15. Device (96) according to any one of claims 1 to 14, wherein the fastening means (22) is configured to assemble with a relief of the piston (62).

16. Access plug (63) for a vehicle (80) air spring (60), the air spring comprising a piston (62) moving along an axis (21) in a cylinder (61), the access plug (63) to the cylinder being placed on the axis of movement of the piston, and being characterized in that it comprises: - at least one removable foam wedge (28, 30, 32, 34) having an assembly relief (29, 31, 33, 35) with at least one reinforcement (25, 96), the assembly relief passing through the wedge completely, - a support (22, 25) comprising at least one reinforcement (25, 96), at least one reinforcement being of a shape corresponding (27) to the assembly relief of at least one said removable wedge and configured to cross the assembly relief of at least one said removable wedge and configured to receive at least one said removable wedge.

17. A fork (70) for a vehicle (80) comprising an air spring (60), the air spring comprising a piston (62) moving about an axis (21) in a cylinder (61) and an access plug (63) to the cylinder located in the axis of movement of the piston and at least one device (20, 90, 95) according to any one of claims 1 to 15 or an access plug according to claim 16.

18. A vehicle (80) comprising a fork (70) comprising an air spring (60), the air spring comprising a piston (62) moving about an axis (21) in a cylinder (61) and an access plug (63) to the cylinder located in the axis of movement of the piston and at least one device (20, 90, 95) according to any one of claims 1 to 15 or an access plug according to claim 16.

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