DAMPING SYSTEM COMPRISING A DUAL-WAY HYDRAULIC DAMPER BODY

Abstract

The invention relates to a damping system (1, 1A) comprising a hollow cylindrical double-walled damper body (2) delimiting an internal volume (3) filled with a damping fluid, a piston assembly comprising a piston (5) arranged to delimit the internal volume into a compression chamber (30) and an expansion chamber (31), the damper body (2) comprising an internal wall (20) and an external wall (21), concentric, delimiting between them a circulation channel for the damping fluid, the damper body (2) having a radial partition (7) connecting the external and internal walls in a sealed manner and dividing the circulation channel into two hydraulic paths distinct from each other and communicating with the compression chamber (30) and the expansion chamber (31), the external wall (21) comprising at least two radial orifices each opening onto one of the hydraulic paths.Figure to be published with the abbreviation: Fig. 1.

Description

Title of the invention: DAMPING SYSTEM COMPRISING A DUAL-WAY HYDRAULIC DAMPER BODY TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to the field of damping systems for vehicles, and in particular for cycles and equivalents.

[0002] The invention relates more particularly to a damping system comprising a hollow cylindrical double-walled damper body delimiting an internal volume filled with a damping fluid, a piston assembly comprising a piston rod mounted to slide axially through the damper body and a piston, integral with the piston rod, arranged within the internal volume so as to delimit the latter into a compression chamber and an expansion chamber, the damper body comprising an internal wall and an external wall, concentric, delimiting between them a circulation channel for the damping fluid, communicating with the compression chamber and the expansion chamber. STATE OF THE ART

[0003] Twin-tube shock absorbers (commonly referred to as "twin-tube shock absorbers") comprise an inner tube delimiting an internal fluid volume (oil), an outer tube delimiting a fluid circulation channel, and at least one flow passage extending through the inner tube to allow fluid communication between said internal fluid volume and the fluid circulation channel. These shock absorbers are further equipped with a remote reservoir (commonly called a "piggyback") for managing the fluid contained in the internal volume when the shock absorber is compressed. The reservoir is mounted at the end of the shock absorber and connected to the internal fluid volume and the fluid circulation channel by at least one orifice provided at the end. During the compression phase, the fluid is sent to the piggyback and then returns to the expansion chamber via the fluid circulation channel delimited by the outer tube.

[0004] The disadvantage of double-walled shock absorbers lies in the imposed position of the external reservoir, namely its position at the end of the shock absorber. Due to this end-mounted positioning, these shock absorbers are dependent on the available space within the bicycle frame and are therefore unsuitable and incompatible with certain bicycle frames.

[0005] The invention aims to remedy these problems by proposing a damping system adaptable to any type of bicycle frame. SUBJECT OF THE INVENTION

[0006] To this end, and according to a first aspect, the invention proposes a damping system comprising a hollow cylindrical double-walled damper body delimiting an internal volume filled with a damping fluid, a piston assembly comprising a piston rod mounted to slide axially through the damper body and a piston, integral with the piston rod, arranged within the internal volume so as to delimit the latter into a compression chamber and an expansion chamber, the damper body comprising an inner wall and an outer wall, concentric, delimiting between them a circulation channel for the damping fluid, the inner wall having at least a first communication orifice ensuring communication between the circulation channel and the compression chamber and at least a second communication orifice ensuring communication between the circulation channel and the expansion chamber,The outer wall includes an opening for communication with the traffic corridor. The damping system is remarkable in that the shock absorber body includes a radial partition that seals the outer and inner walls together and divides the traffic corridor into two distinct hydraulic paths. One of these hydraulic paths communicates with the compression chamber through the first opening, and the other with the expansion chamber through the second opening in the inner wall. The outer wall includes at least two radial openings, one opening onto the hydraulic path communicating with the compression chamber, and the other opening onto the hydraulic path communicating with the expansion chamber.

[0007] Thus, thanks to the presence of the partition, two independent hydraulic circuits are created, namely a compression circuit and an expansion circuit, with the outlet ports of each of these circuits being able to be located at any point on the shock absorber. The position of the reservoir or any other external equipment intended to be coupled to the double-walled shock absorber is therefore no longer limited to the end position alone, as is the case with prior art double-walled shock absorbers.

[0008] Advantageously, the damping system comprises an annular sealing gasket interposed radially between the inner and outer walls, said gasket forming the partition. This arrangement has the advantage of simplifying the manufacture and assembly of the constituent parts of the shock absorber body.

[0009] Advantageously, the first and / or second communication orifice(s) is / are arranged to form a radial fluidic passage through the inner wall.

[0010] According to a particularly advantageous embodiment, the inner wall has a series of first and second communication ports arranged axially. These first and second communication ports are calibrated to have progressively smaller diameters towards the extremities of the shock absorber body. Thanks to the double-walled architecture of the shock absorber body and the separating partition, the first and second communication ports, thus arranged, form progressive double hydraulic stops, namely in compression and rebound. During the movement of the piston in compression, the first communication ports progressively close, thereby increasingly reducing the flow of fluid from the compression chamber to the associated hydraulic circuit and thus progressively increasing the braking force. This results in progressive braking of the piston rod in compression.Similarly, during the piston's expansion stroke, the second communication ports gradually close, progressively reducing the flow of fluid from the expansion chamber to the associated hydraulic circuit and thus increasing the braking force. This results in progressive braking of the piston rod during expansion.

[0011] In order to prevent the suction effect of the piston in compression or expansion, a relief valve is advantageously provided respectively in the compression and expansion chambers, at each end of the shock absorber body.

[0012] Advantageously, the first and / or second communication orifice(s) is / are arranged to form an axial fluidic passage through the internal wall.

[0013] Advantageously, the damping system includes a connecting sleeve for an external reservoir (or other equipment) to the internal volume of the damper body. This connecting sleeve is rotatably mounted on a lateral portion of the external wall of the damper body and arranged to ensure fluid communication between the external reservoir (or other equipment) and each of the hydraulic channels. Thanks to the connecting sleeve, the orientation of the external reservoir (or other equipment) connected to the damper body can be adapted to the cycle on which the damping system is mounted.

[0014] Advantageously, the damping system includes means for axially locking the connecting sleeve on the shock absorber body.

[0015] Advantageously, the connecting sleeve comprises an annular body for retaining on the shock absorber body, provided, on its inner face, with two circumferential grooves, and on its outer face, with a radial end through which are passed two fluid passage channels, each channel opening into one of the grooves.

[0016] According to another aspect, the invention proposes a damping system comprising a hollow cylindrical double-walled damper body delimiting an internal volume filled with a damping fluid, a piston assembly comprising a piston rod mounted to slide axially through the damper body and a piston, integral with the piston rod, arranged within the internal volume so as to delimit the latter into a compression chamber and an expansion chamber, the damper body comprising an inner wall and an outer wall, concentric, delimiting between them a circulation channel for the damping fluid, the inner wall having at least a first communication orifice ensuring communication between the circulation channel and the compression chamber and at least a second communication orifice ensuring communication between the circulation channel and the expansion chamber,the outer wall having an opening for communication with the traffic corridor, the damping system being notable in that it includes a connecting sleeve from an external reservoir (or other equipment) to the internal volume of the damper body, rotatably mounted on a lateral portion of the outer wall of said damper body and arranged to ensure fluid communication between the external reservoir (or other equipment) and each of the hydraulic channels.

[0017] Other advantageous and non-limiting features of this aspect of the invention may be provided, taken alone or in any technically feasible combination: - the connecting sleeve is free to rotate around its axis. - the connecting sleeve is free to rotate through 360° degrees around its axis. - the damping system includes means for axially locking the connecting sleeve on the shock absorber body. - the connecting sleeve has an annular body for retaining on the shock absorber body, provided, on its inner face, with two circumferential grooves, and on its outer face, with a radial end through which are passed two fluid passage channels, each channel opening into one of the grooves. - the shock absorber body includes a radial partition connecting the external and internal walls in a watertight manner and dividing the circulation channel into two distinct hydraulic paths, one of the hydraulic paths communicating with the compression chamber through the first orifice, the other hydraulic path communicating with the expansion chamber through the second orifice provided in the internal wall, the external wall comprising at least two radial orifices, one of the orifices radial openings onto the hydraulic channel communicating with the compression chamber, the other opening onto the hydraulic channel communicating with the expansion chamber. - the damping system includes an annular sealing gasket interposed radially between the inner wall and the outer wall, said gasket forming the partition wall. - the first and / or second communication orifice(s) is / are arranged to form a radial fluidic passage through the inner wall. - the first and / or second communication orifice(s) is / are arranged to form an axial fluidic passage through the internal wall. - the internal wall has a series of first and second communication ports distributed axially, said first and second communication ports being calibrated to form progressive double hydraulic stops. - a relief valve is provided in the compression and expansion chambers, at each end of the shock absorber body. BRIEF DESCRIPTION OF THE FIGURES

[0018] Other features and advantages of the invention will become apparent from the detailed description of the invention that follows, given by way of example and with reference to the accompanying figures in which:

[0019] [Fig.1] Fig.1 represents a damping system according to a first embodiment of the invention;

[0020] [Fig.2] Fig.2 represents a damping system according to a second example of the implementation of the invention;

[0021] [Fig.3] Fig.3 represents the damping system of Fig.2 equipped with a rotating sleeve;

[0022] [Fig.4] Fig.4 shows a cross-sectional view of the damping system of the [Fig.3] along axis IV-IV;

[0023] [Fig. 5] Fig. 5 represents a partial perspective view of the system damping of the [Fig.3];

[0024] [Fig. 6] Fig. 6 shows a cross-sectional view of the damping system of the [Fig.5] along the VLVI axis;

[0025] [Fig.7] Fig.7 represents a cross-sectional view of a damping system according to another example of the realization of the invention;

[0026] [Fig-8] Fig. 8 represents a perspective cross-sectional view of the system damping of the [Fig.7];

[0027] [Fig.9] Fig.9 represents a cross-sectional view of a damping system according to another example of the realization of the invention.

[0028] For greater clarity, identical or similar elements of the different embodiments are identified by identical reference signs throughout the figures. DETAILED DESCRIPTION OF THE INVENTION

[0029] In relation to [Fig. 1], a damping system 1 is described comprising, generally, on the one hand, a hollow cylindrical damper body 2 delimiting an internal volume 3 filled with a damping fluid, and on the other hand, a piston assembly comprising a piston rod 4 mounted to slide axially through the damper body 2 and a piston 5 integral with the piston rod 4. The piston 5 is arranged within the internal volume 3 so as to delimit the latter into a compression chamber 30 and an expansion chamber 31.

[0030] As shown in [Fig. 1], the damper body 2 is double-walled. It comprises a concentric inner wall 20 and an outer wall 21, delimiting between them a circulation channel 60 for the damping fluid. In the illustrated embodiment, the outer wall 21 completely surrounds the inner wall 20, i.e., radially and axially.

[0031] According to the invention, the shock absorber body 2 comprises a radial partition 7 connecting the internal and external walls 20, 21 to each other in a sealed manner, thus dividing the traffic corridor 6 into two hydraulic paths 60, 61 distinct from each other.

[0032] One of the hydraulic channels 60 communicates with the compression chamber 30 through orifices 10, while the other hydraulic channel 61 communicates with the expansion chamber 31 through orifices 11 formed in the inner wall 20. In the illustrated embodiment, the orifices 10 and 11 are located on the inner wall 20 to define axial fluidic communications between the chambers and the associated hydraulic channels. In the illustrated example, the inner wall 20 has a plurality of orifices 10 and 11 communicating respectively with the compression and expansion chambers. It is understood that an inner wall comprising a single orifice 10 opening into the compression chamber and a single orifice 11 opening into the expansion chamber can be provided without departing from the scope of the invention.

[0033] The outer wall 21 has two sets of orifices 12, 13 forming radial fluidic openings, one of the sets of orifices 12 opening onto the pathway Hydraulic orifices 60 communicate with the compression chamber 30, while the other set of orifices opens onto the hydraulic channel 61, which communicates with the expansion chamber 31. The two sets of orifices are advantageously located near the partition 7, on either side of it. Although not shown, the orifices of the two sets of orifices 12 and 13 are intended to communicate fluidly with an external reservoir or any external hydraulic element connected to the shock absorber body. As with the inner wall 20, the outer wall 31 may be provided with a single orifice 12 opening onto the hydraulic channel 60 and a single orifice 13 opening onto the hydraulic channel 61 without departing from the scope of the invention.

[0034] In the embodiment illustrated in [Fig. 1], the partition 7 is formed by a radial rib connecting the inner wall 20 and the outer wall 21 from end to end and advantageously formed in one piece with both the inner and outer walls. It is understood that the damping system 1 is not limited to this type of partition and that other arrangements can be provided, provided that the fluid separation of the traffic corridor is achieved in a watertight manner. The partition can thus be formed by an O-ring, as in the embodiment illustrated in [Fig. 2], which will be described later.

[0035] The fluid displacement during a compression stroke and respectively during the retraction of the piston rod 4 within the shock absorber body is represented by arrows. Thus, during a compression stroke, the fluid flows through the radial orifices 12 of the inner wall 20, then through the hydraulic channel 60 to exit through the radial orifice 12 of the outer wall 21, while during the retraction of the piston rod 4, the fluid flows through the orifice 11 of the inner wall 20, then through the hydraulic channel 61 to exit through the radial orifice 13 of the outer wall 21.

[0036] Figure 2 illustrates another example of the implementation of a damping system. AI according to the invention. The system differs from that just described in particular by the arrangement of the double wall and the position of the communication ports between the chambers 60, 61 and the inner wall 20.

[0037] In this example, the shock absorber body 2 comprises two axially opposite end walls connected to each other by a double lateral wall, namely an inner wall 20 and the outer wall 21, delimiting between them a circulation corridor extending axially.

[0038] The inner wall 20 is provided with at least one orifice, in the illustrated example several orifices 10a, 1a, some ensuring communication between the hydraulic channel 60 and the compression chamber 30, others ensuring communication between the hydraulic channel 61 and the expansion chamber 31. The communication orifices 10a, 1a thus define radial fluidic communications between the chambers and the associated hydraulic pathways.

[0039] The damping system IA also differs from that illustrated in [Fig. 1] by the configuration of the partition 7, the latter being formed by an annular sealing gasket 7A interposed radially between the inner wall 20 and the outer wall 21. In the illustrated example, the O-ring is held between two radial fins 8, 9 extending between the inner wall 20 and the outer wall 21. Advantageously, the radial fins 8, 9 are supported by the outer wall 21 and are formed from the outer wall 21. The presence of fins 8, 9 has the advantage of ensuring axial locking of the sealing gasket.

[0040] According to a particularly advantageous configuration, the damping system according to the invention comprises a connecting sleeve 14 for connecting an external reservoir (not shown) to the internal volume 3 of the damper body 2, namely the expansion chamber 31 and the compression chamber 30. Such a connecting sleeve 14 is shown mounted on the damper body 2 of the damping system IA in [Fig. 2]. It is understood that the connecting sleeve 14 is not limited to this configuration of the damper body 2, and that it can be used on the damper body 2 of the damping system 1 in [Fig. 1] as well as with any other damping system according to the invention (such as, for example, the one shown in Figures 7 and 8). It can also be used with a damping system without a separating partition, such as the damping system 100 shown as an example in [Fig. 7].

[0041] The connecting sleeve 14, arranged to ensure fluid communication between the external reservoir and the compression and expansion chambers 31 via the hydraulic channels 60, 61, is mounted on the lateral outer wall 21 of the shock absorber body 2. It is mounted to rotate freely around the outer wall 21 through a 360-degree rotation. The presence of the sleeve thus allows the angular position of the external reservoir or the external hydraulic element connected to the shock absorber body to be selected manually, while also allowing the handling of the external element to be adapted to the user (left-handed or right-handed) and their environment (space, available volume, interaction, etc.).

[0042] As illustrated in Figures 3 to 6, the connecting sleeve 14 comprises an annular retaining body 15 on the shock absorber body 2, extended by a radial connecting end 16 to which the external reservoir is intended to be connected. The retaining body 15 is provided, on its inner face, with two circumferential grooves 15a, 15b. The radial end 16 is traversed through by two fluid passage channels 16a, 16b, each channel opening respectively into one of the grooves.

[0043] Advantageously the damping system IA includes means for axially locking the connecting sleeve 14 on the shock absorber body 2, in order to prevent the sleeve from moving along the shock absorber body 2 and to prevent a possible break in fluid connection between the external reservoir and the compression and expansion chambers 30, 31 of the shock absorber body 2.

[0044] Thanks to the connecting sleeve, the orientation of the external reservoir can be adapted to the frame of the cycle on which the damping system is mounted.

[0045] Figures 7 and 8 illustrate another embodiment of a damping system IB according to the invention. This system replicates the double-wall arrangement of the embodiment of system 1 in [Fig. 1]. However, it differs in that the inner wall 20 is provided, on the one hand, with orifices 10, 11 defining axial fluidic communications between the chambers and the hydraulic channels, and on the other hand, with orifices 10a, 11a defining radial fluidic communications between the chambers and the associated hydraulic channels. The IB system further includes compensation (or relief) valves 18, 19, which are annular in shape in the illustrated example, arranged in the compression and expansion chambers at each end of the damper body, opposite the axial orifices 10, 11.In the illustrated example, the compensating valve 18 located in the compression chamber is shown closed, while the compensating valve 19 located in the expansion chamber is shown open. This state is reached just after the hydraulic expansion stops are reached, i.e., at the beginning of the compression phase. The compensating valve 18 will open while the compensating valve 19 will close at the very beginning of the expansion phase, just after the hydraulic compression stops are reached.

[0046] Figure 9 illustrates a damping system 100 comprising a single hydraulic channel (double-walled damping body without a separating partition). In this example, the retaining body 15 of the connecting sleeve 14 is provided, on its inner face, with a single circumferential groove, the radial end being traversed completely by a single fluid passage channel opening into the groove. As in the previously described example, the connecting sleeve 14A is mounted to rotate freely around the lateral outer wall 21 of the damping body through a 360-degree rotation. Similarly, as before, means for axially locking the connecting sleeve 14 on the damper body 2 can advantageously be provided to prevent the sleeve from moving along the damper body 2.

[0047] The invention is described above by way of example. It is understood that a person skilled in the art is able to carry out different embodiments of the invention without departing from the scope of the invention.

Claims

1. Demands Depreciation system (1, IA, IB) comprising: - a hollow cylindrical double-walled shock absorber body (2) delimiting an internal volume (3) filled with a damping fluid, - a piston assembly comprising a piston rod (4) mounted to slide axially through the shock absorber body (2) and a piston (5), integral with the piston rod (4), arranged within the internal volume (3) so as to delimit the latter into a compression chamber (30) and an expansion chamber (31), - the shock absorber body (2) comprising an inner wall (20) and an outer wall (21), concentric, delimiting between them a circulation channel for the damping fluid, the inner wall (20) having at least a first communication orifice ensuring communication between the circulation channel and the compression chamber (30) and at least a second communication orifice ensuring communication between the circulation channel and the expansion chamber (31), the outer wall (21) having a communication orifice with the circulation channel, the shock absorber body (2) having a radial separating partition (7) connecting the outer and inner walls to each other in a watertight manner and dividing the circulation channel into two hydraulic paths distinct from each other, one of the hydraulic paths communicating with the compression chamber (30) through the first orifice,the other hydraulic path communicating with the expansion chamber (31) through the second orifice provided in the inner wall (20), the outer wall (21) comprising at least two radial orifices, one of the radial orifices opening onto the hydraulic path communicating with the compression chamber (30), the other orifice opening onto the hydraulic path communicating with the expansion chamber (31), characterized in that it comprises a connecting sleeve (14) from a reservoir or any other external equipment to the internal volume of the shock absorber body (2), said connecting sleeve (14) being rotatably mounted on a lateral portion of the external wall (21) of said shock absorber body (2) and arranged to ensure fluid communication between the reservoir or any other external equipment and each of the hydraulic channels.

2. Damping system (1, IA, IB) according to claim 1, characterized in that it comprises an annular sealing gasket interposed radially between the inner wall (20) and the outer wall (21), said gasket forming the separating partition (7).

3. Damping system (1, IA, IB) according to claim 1 or claim 2, characterized in that the first(s) and / or second communication orifice(s) is / are arranged to form a radial fluidic passage through the inner wall (20).

4. Damping system (1, IA, IB) according to any one of claims 1 to 3, characterized in that the inner wall (20) has a series of first and second communication ports distributed axially, said first and second communication ports being calibrated to form progressive double hydraulic stops.

5. Damping system (1, IA, IB) according to any one of claims 1 to 4, characterized in that a relief valve is provided in the compression and expansion chambers, at each of the ends of the shock absorber body.

6. Damping system (1, IA, IB) according to any one of the preceding claims, characterized in that the first and / or second communication orifice(s) is / are arranged to form an axial fluidic passage through the inner wall (20).

7. Damping system (1, IA, IB) according to any one of the preceding claims, characterized in that it comprises means for axially locking the connecting sleeve (14) on the damper body (2).

8. Damping system (1, IA, IB) according to any one of the preceding claims, characterized in that the connecting sleeve (14) comprises an annular retaining body on the damper body (2), provided, on its inner face, with two grooves circumferential, and on its external face, a radial tip crossed through by two fluid passage channels, each channel opening into one of the grooves.

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