ADJUSTABLE BLEED VALVE ASSEMBLY FOR SHOCK ABSORBER

Abstract

The present disclosure relates to an adjustable bleed valve assembly for a shock absorber. The bleed valve assembly includes: a first adjustable bleed valve, and a second adjustable bleed valve arranged in series with the first adjustable bleed valve, wherein the first adjustable bleed valve and the second adjustable bleed valve are each pressure independently adjustable between a first open state and a second open state, wherein each adjustable bleed valve is adapted to throttle a damping fluid in the piston rod more in the second open state than in the first open state, wherein the first adjustable bleed valve and the second adjustable bleed valve are each adjustable between the first open state and the second open state independently from one another. An adjustment device and a method for adjusting the bleed valve assembly is also provided.

Claims

1.-20. (canceled)

21. A bleed valve assembly for arrangement in a bleed flow channel in a piston rod of a shock absorber, the bleed valve assembly comprising: a first adjustable bleed valve; and a second adjustable bleed valve arranged in series with the first adjustable bleed valve; wherein the first adjustable bleed valve and the second adjustable bleed valve are each independently pressure adjustable between a first open state and a second open state, wherein each adjustable bleed valve is adapted to throttle a damping fluid in the piston rod more in the second open state than in the first open state; wherein the first adjustable bleed valve and the second adjustable bleed valve are each adjustable between the first open state and the second open state independently from one another; wherein the first adjustable bleed valve and the second adjustable bleed valve are adapted to throttle a damping fluid by a common throttling member; wherein the first adjustable bleed valve is adjustable between the first open state and the second open state by moving the throttling member.

22. The bleed valve assembly according to claim 21, wherein the first adjustable bleed valve and the second adjustable bleed valve are adjustable between the first open state and the second open state from a distance.

23. The bleed valve assembly according to claim 21, wherein the first adjustable bleed valve includes a first bleed valve member adapted to interact with the throttling member such that the throttling member adjustably covers at least a portion of one or more bleed flow throttling openings associated with the first adjustable bleed valve.

24. The bleed valve assembly according to claim 21, wherein the second adjustable bleed valve includes a second bleed valve member adapted to interact with the throttling member such that the throttling member adjustably covers at least a portion of one or more bleed flow throttling openings associated with the second adjustable bleed valve.

25. The bleed valve assembly according to claim 21, wherein the throttling member is held fixed relative the first bleed valve member when the second adjustable bleed valve is adjusted between the first open state and the second open state.

26. The bleed valve assembly according to claim 24, wherein the second bleed valve member is held fixed relative the throttling member when the first adjustable bleed valve is adjusted between the first open state and the second open state.

27. The bleed valve assembly according to claim 23, wherein the throttling member is coupled to a first adjusting device by a first coupling member adapted to enable adjustment of the position of the throttling member relative the first bleed valve member.

28. The bleed valve assembly according to claim 24, wherein the second bleed valve member is coupled to a second adjusting device by a second coupling member adapted to enable adjustment of the position of the second bleed valve member relative to the throttling member.

29. The bleed valve assembly according to claim 27, wherein the second bleed valve member is slidably arranged in the first coupling member.

30. The bleed valve assembly according to claim 24, wherein the throttling member, the first bleed valve member and the second bleed valve member are concentrically arranged.

31. The bleed valve assembly according to claim 21, comprising a rebound check valve adapted to open at a predetermined damping fluid pressure during rebound.

32. The bleed valve assembly according to claim 21, comprising a compression check valve adapted to open at a predetermined damping fluid pressure during compression.

33. Bleed valve assembly according to claim 31, wherein the rebound check valve or the compression check valve respectively is adapted to open from an open state to a further open state.

34. A shock absorber comprising: a piston rod including a bleed flow channel, and a bleed valve assembly according to claim 21, arranged in said bleed flow channel.

35. A method of adjusting the adjustable bleed valve assembly according to claim 21, comprising actuating at least one of the first and second adjustable bleed valves between the first open state and the second open state, or between an open state and a closed state, so as to achieve a desired damping force characteristic during compression strokes and/or rebound strokes.

36. The method according to claim 35, comprising actuating the first and second adjustable bleed valves between the first open state and the second open state, or between an open state and a closed state, respectively, independently from each other.

37. The method according to claim 35, comprising moving a throttling member relative a first bleed valve member of the first adjustable bleed valve so as to adjustably cover at least a portion of one or more bleed flow throttling openings associated with the first adjustable bleed valve.

38. The method according to claim 35, comprising moving a second bleed valve member of the second adjustable bleed valve relative the throttling member so as to adjustably cover at least a portion of one or more bleed flow throttling openings associated with the second adjustable bleed valve.

39. The method according to claim 35, comprising holding the throttling member fixed relative the first bleed valve member of the first adjustable bleed valve when adjusting the second adjustable bleed valve.

40. The method according to claim 35, comprising holding the second bleed valve member fixed relative the throttling member when adjusting the first adjustable bleed valve, and/or opening a compression check valve at a predetermined damping fluid pressure, and/or opening a rebound check

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0092] The disclosure will in the following be described in more detail in the non-limiting detailed description of example embodiments, with reference to the enclosed drawings, wherein:

[0093] FIG. 1 shows a cross sectional view of an adjustable bleed valve assembly arranged in a piston rod, according to one embodiment of the disclosure;

[0094] FIG. 2 shows a cross sectional view of an adjustable bleed valve assembly according to one embodiment of the disclosure;

[0095] FIG. 3 shows a flow diagram of an adjustable bleed valve assembly according to one embodiment of the disclosure;

[0096] FIG. 4 shows a cross sectional view of an exploded view of an adjustable bleed valve assembly according to one embodiment of the disclosure;

[0097] FIG. 5a-5d show the working principle of an adjustable bleed valve of the adjustable bleed valve assembly, according to one embodiment of the disclosure, as seen in cross sectional view;

[0098] FIG. 6a-6b show the working principle of the adjustable bleed valve assembly according to one embodiment of the disclosure, as seen in cross sectional view;

[0099] FIG. 7 shows a portion of a shock absorber, comprising an adjustable bleed valve assembly, according to one embodiment of the disclosure;

[0100] FIG. 8 shows a cross sectional view of the first and second coupling member according to one embodiment of the disclosure;

[0101] FIG. 9 shows a block diagram of the disclosure according to one embodiment of the present disclosure;

[0102] FIG. 10 shows damping force characteristics during compression strokes and rebound strokes in relation to compression adjustments of the adjustable bleed valve according to one embodiment of the disclosure;

[0103] FIG. 11 shows damping force characteristics during compression strokes and rebound strokes in relation to rebound adjustments of the adjustable bleed valve according to one embodiment of the disclosure;

[0104] FIG. 12 shows a flow chart of a method for adjusting the adjustable bleed valve assembly.

DETAILED DESCRIPTION

[0105] The present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which example embodiments of the disclosure are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. In the drawings, like numbers refer to like elements. Moreover, all figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the disclosure, wherein other parts may be omitted or merely suggested.

[0106] FIG. 1 shows a cross sectional view of an adjustable bleed valve assembly 1 arranged in a piston rod 110, according to one embodiment of the disclosure. The piston rod 110 is adapted to move in a working cylinder (not shown). A piston head 101 is arranged on the piston rod 110, which piston head 101 is secured in place by a locking nut 107 adapted to engage with grooves at the end of the piston rod 110. The piston head 101 divides the working chamber into a compression chamber 100C and a rebound chamber 100R. The piston head 101 comprises a base structure 102 which structurally defines one or more channels connecting the compression chamber 100C and the rebound chamber 100R, thereby enabling a damping fluid flow between the compression chamber 100C and the rebound chamber 100R. On each side of the base structure, shims 103, 104 are located. The shims 103, 104 are adapted to close, in an unflexed position, at least a portion of the one or more channels of the base structure 102 of the piston head 101, and, in a flexed position, allowing an increased flow between the compression chamber 100C and the rebound chamber 100R, thereby regulating the damping fluid flow between the compression chamber 100C and the rebound chamber 100R during compression strokes and rebound strokes, respectively. The shims 103, 104 are each sandwiched in-between the base structure 102 and a corresponding place 105, 106, respectively.

[0107] Moreover, the piston rod 110 structurally defines a bleed flow channel extending along a longitudinal axis L of the piston rod 110, which bleed flow channel fluidly connects the compression chamber 100C and the rebound chamber 100R by means of a compression chamber opening 110a and a plurality of rebound chamber openings 110b. The compression chamber opening 110a is located at a longitudinal end of the piston rod 110 on a compression side of the piston head 101. The plurality of rebound chamber openings 110b are located on the piston rod 110 on a rebound side of the piston head 101.

[0108] The bleed valve assembly 1 according to one embodiment of the present disclosure is shown in FIG. 2 more clearly. It structurally defines a bleed flow channel P adapted for guiding a damping fluid between a first opening and a second opening of the bleed valve assembly 1 (see FIG. 3). Moreover, the bleed valve assembly 1 is adapted in shape and size to be arranged in a bleed flow channel in a piston rod 110 as herein detailed, so that the damping fluid in the bleed flow channel flows through the bleed valve assembly 1.

[0109] Hence, the adjustable bleed valve assembly 1 is adapted to guide, when arranged in the bleed flow channel of the piston rod 110, a damping fluid through the adjustable bleed valve assembly 1 between the compression chamber 100C and the rebound chamber 100R during compression and rebound strokes.

[0110] The adjustable bleed valve assembly 1 comprises a first adjustable bleed valve 10 and a second adjustable bleed valve 20. The first adjustable bleed valve 10 and the second adjustable bleed valve 20 are arranged in series. Specifically, the bleed valve assembly 1 is arranged in the bleed flow channel so that the first adjustable bleed valve 10 is fluidly arranged between the compression chamber 100C and the second adjustable bleed valve 20. The second adjustable bleed valve 20 is fluidly arranged between the rebound chamber 100R and the first adjustable bleed valve 10.

[0111] The first adjustable bleed valve 10 comprises a first bleed valve member 11 and a first base member 12. Both the first bleed valve member 11 and the first base member 12 have cylindrical shapes, wherein the first bleed valve member 11 has a smaller diameter than the first base member 12. The first bleed valve member 11 and the first base member 12 are coaxially arranged to each other. Similarly, the second adjustable bleed valve 20 comprises a second bleed valve member 21 and a second base member 22. Both the second bleed valve member 21 and the second base member 22 have cylindrical shapes, wherein the second bleed valve member 21 has a smaller diameter than the second base member 22. The second bleed valve member 21 and the second base member 22 are coaxially arranged to each other.

[0112] The adjustable bleed valve assembly 1 comprises a throttling member 50. The throttling member 50 has a cylindrical shape and is provided with a first end opening located at a first longitudinal end 50a of the throttling member 50. Furthermore, the throttling member 50 is provided with a second end opening located at a second longitudinal end 50b of the throttling member 50. The first adjustable bleed valve 10 and the second adjustable bleed valve 20 are arranged on opposite sides of the throttling member 50. The first adjustable bleed valve 10, the second adjustable bleed valve 20 and the throttling member 50 are arranged concentrically along a longitudinal axis of the throttling member 60.

[0113] The first bleed valve member 11 of the first adjustable bleed valve 10 is adapted to interact with the throttling member 60 such that at least a portion of one or more bleed flow throttling openings 11b associated with the first adjustable bleed valve 10 is covered. As can be seen in FIGS. 1 and 2, the one or more bleed flow throttling openings 11b associated with the first adjustable bleed valve 10 are arranged on the first bleed valve member 11 of the first adjustable bleed valve 10.

[0114] Likewise, the second bleed valve member 21 of the second adjustable bleed valve 20 is adapted to interact with the throttling member 50 such that at least a portion of one or more bleed flow throttling openings 21b associated with the second adjustable bleed valve 20 is covered. As can be seen in FIGS. 1 and 2, the one or more bleed flow throttling openings 21b associated with the second adjustable bleed valve 20 are arranged on the second bleed valve member 21 of the second adjustable bleed valve 20.

[0115] Moreover, the bleed valve assembly 1 comprises a rebound check valve 30 and a compression check valve 40. The rebound check valve 30 is arranged in the first base member 12 of the first adjustable bleed valve 10. The compression check valve 40 is arranged in the second base member 22 of the second adjustable bleed valve 20.

[0116] The first adjustable bleed valve 10, the second adjustable bleed valve 20, and the throttling member 50 are adapted to be independently moveable relative each other. By this, a novel damping force characteristic may be achieved, see FIGS. 10 and 11.

[0117] FIG. 3 shows a flow diagram of the adjustable bleed valve assembly 1 presented in FIG. 2 according to one embodiment of the disclosure. Assuming a compression stroke is taking place, the bleed flow will flow through the bleed valve assembly 1 along the bleed flow path P in a direction from the compression chamber 100C toward the rebound chamber 100R. First, the bleed flow flows through the first adjustable bleed valve 10 and then through the second adjustable bleed valve 20 before reaching the rebound chamber 100R.

[0118] The compression check valve 40 is fluidly arranged in parallel with the second adjustable bleed valve 20 and is adapted to keep an auxiliary compression flow path P.sub.C closed unless the pressure of the damping fluid acting on the compression check valve 40 equals or exceeds a predetermined opening pressure level, in which case it opens, allowing a portion of the damping fluid to flow along the auxiliary compression flow path Pc, in parallel with a portion of the bleed flow path P.

[0119] Now, assuming a rebound stroke is taking place, the bleed flow will flow through the bleed valve assembly 1 along the bleed flow path P in a direction from the rebound chamber 100R toward the compression chamber 100C. First, the bleed flow flows through the second adjustable bleed valve 20 and then through the first adjustable bleed valve 10 before reaching the compression chamber 100C.

[0120] The rebound check valve 30 is fluidly arranged in parallel with the first adjustable bleed valve 10 and is adapted to keep an auxiliary rebound flow path P.sub.R closed unless the pressure of the damping fluid acting on the rebound check valve 30 equals or exceeds a predetermined opening pressure level, in which case it opens, allowing a portion of the damping fluid to flow along the auxiliary rebound flow path P.sub.R, in parallel with a portion of the bleed flow path P.

[0121] FIG. 4 shows an exploded cross-sectional view of the adjustable bleed valve assembly 1 according to one embodiment of the disclosure. In the following, a more detailed description of each of the components of the bleed valve assembly 1 is provided. As can be seen in FIG. 4, the first adjustable bleed valve 10 is coaxially arranged in the bleed flow channel of the piston rod 110. In particular, the first base member 12 of the first adjustable bleed valve 10 is fixedly arranged to the inside of the piston rod 110, and the first bleed valve member 11 extends out of the first base member 12 further into the bleed flow channel in the piston rod 110. The first bleed valve member 11 structurally defines a central opening 11a located at the longitudinal end of the cylindrical body facing away from the first base member 12. The central opening 11a leads into a cylindrical cavity inside the first bleed valve member 11. Along the cylindrical wall of the first bleed valve member 11, a plurality of bleed flow throttling openings 11b is arranged, in this case two bleed flow throttling openings 11b. These are arranged on opposite sides of the valve member 11.

[0122] The first base member 12 comprises a first cylindrical cavity, which is at least partly bounded at each longitudinal end of the cylindrical cavity by protrusions of the first base member 12. A plurality of auxiliary flow path openings 12b is arranged along the cylinder wall of this first cylindrical cavity, and more precisely, two auxiliary flow path openings 12b are arranged along this cylindrical wall. Moreover, these are arranged on opposing sides of the cylinder wall.

[0123] In connection to this first cylindrical cavity, a second cylindrical cavity is arranged. The first base member 12 is so structurally adapted so that the second cylindrical cavity is coaxially arranged with the first cylindrical cavity. Two bleed flow channels 12c extend into the first base member into the second cylindrical cavity.

[0124] The rebound check valve 30 comprises a rebound check valve cap 31 and a rebound check valve spring 32. The rebound check valve 30 is adapted to be arranged in the first cylindrical cavity of the first base member 12 of the first adjustable bleed valve 10. The rebound check valve spring 32 is adapted to bias the rebound check valve cap 31 toward the first bleed valve member 11 of the first adjustable bleed valve 10 so that the central opening 12a is closed. The rebound check valve spring 32 is adapted with such a spring spiral diameter so that a first longitudinal end abuts protrusions in the first cylindrical cavity of the first base member 12 while the opposite longitudinal end of the rebound check valve spring 32 abuts the rebound check valve cap 31. When arranged in the first adjustable bleed valve 10, the rebound check valve cap 31 is biased by the rebound check valve spring 32 toward the first bleed valve member 11, so that it engages with protrusions of the first base member 12, thereby closing the central opening 12a of the first adjustable bleed valve. When the rebound check valve 30 is in a closed position, a surface on the rebound check valve cap 31, having area A30, is exposed as seen from the cylindrical cavity of the valve member 11.

[0125] The throttling member 50 comprises a cylindrical body having a first longitudinal end 50a and a second longitudinal end 50b. The throttling member 50 is coaxially arranged to the first coupling member 130, which will be detailed more at a later section of this detailed description. The first coupling member 130 structurally defines a cylindrical cavity for receiving the second adjustable bleed valve 20. Two bleed flow openings 130a are arranged opposite each other along the cylindrical wall of the cylindrical cavity of the first coupling member 130, which fluidly connects the cylindrical cavity with the outside of the first coupling member 130.

[0126] The second adjustable bleed valve 20 comprises a second bleed valve member 21 and a second base member 22. The second adjustable bleed valve 20 is coaxially arranged to the second coupling member 140. In particular, the second base member 22 of the second adjustable bleed valve 20 is fixedly arranged to the second coupling member 140, and the second bleed valve member 21 extends out of the second base member 22 away from the second coupling member 140. The valve member 21 structurally defines a bleed flow opening 21a located at the longitudinal end of the cylindrical body facing away from the second base member 22. The bleed flow opening 21a leads into a cylindrical cavity inside the second bleed valve member 21. Along the cylindrical wall of the second bleed valve member 21, a plurality of bleed flow throttling openings 21b is arranged, in this case two bleed flow throttling openings. These are arranged on opposite sides of the valve member 21.

[0127] The second base member 22 of the second adjustable valve 20 comprises a single cylindrical cavity, which is at least partly bounded at each longitudinal end of the cylindrical cavity by means of protrusions. A plurality of auxiliary flow path openings 22b is arranged along the cylinder wall of this first cylindrical cavity, and more precisely, two auxiliary flow path openings 22b are arranged along this cylindrical wall. Moreover, these are arranged on opposing sides of the cylinder wall.

[0128] The compression check valve 40 comprises a compression check valve cap 41 and a rebound check valve spring 42. The compression check valve 40 is adapted to be arranged in the single cylindrical cavity of the base member 22 of the second adjustable bleed valve 20. The compression check valve spring 42 is adapted to bias the compression check valve cap 41 toward the second bleed valve member 21 of the second adjustable bleed valve 20 so that a central opening 22a is closed. The compression check valve spring 42 is adapted with such a spring spiral diameter so that a first longitudinal end abuts a base in the single cylindrical cavity of the base member 22 while the opposite longitudinal end of the compression check valve spring 42 abuts the compression check valve cap 41. When arranged in the second adjustable bleed valve 20, the compression check valve cap 41 is biased by the compression check valve spring 42 toward the second bleed valve member 21, so that it engages with protrusions of the second base member 22, thereby closing the central opening 22a of the second adjustable bleed valve 20. When the compression check valve 40 is in a closed position, a surface on the compression check valve cap 41, having area A40, is exposed as seen from the cylindrical cavity of the valve member 21.

[0129] The throttling member 50 is adapted to be coaxially arranged to the first adjustable bleed valve 10, so that it interacts with the first bleed valve member 11. Moreover, the throttling member 50 is adapted to be moved in position relative the first adjustable bleed valve 10 so that it adjustably covers the one or more bleed flow throttling openings 11b located on the first bleed valve member 11. By moving the throttling member 50 in a longitudinal direction, the portion of covered bleed flow throttling openings 11b on the first bleed valve member 11 may be changed. The second adjustable bleed valve 20 is adapted to be coaxially arranged relative the throttling member 50, so that the second bleed valve member 21 interacts with the throttling member 50. Moreover, the second adjustable bleed valve 20 and the second coupling member 140 are adapted to be at least partly arranged in the first coupling member 130.

[0130] FIGS. 5a-5d show the working principle of the first adjustable bleed valve 10 of the adjustable bleed valve assembly 1, according to one embodiment of the disclosure, as seen in cross sectional view. Although being somewhat structurally different in some embodiments, the second adjustable bleed valve 20 (not shown) works in a similar manner.

[0131] As seen in the FIG. 5a, the first adjustable bleed valve 10 is in a first open state O1, at which state the throttling member 50 allows for an increased flow or a maximum flow through the plurality of bleed flow throttling openings 11b on the first bleed valve member 11. In this first open state O1, the throttling member 50 is in a position such that the first longitudinal end 50a of the throttling member 50 is placed a first distance d1 away from the base member of the first adjustable bleed valve 10.

[0132] In FIG. 5b, the first longitudinal end 50a of the throttling member 50 is moved closer to the first base member 12 of the adjustable bleed valve 10, such that the first longitudinal end 50a of the throttling member 60 is placed a distance d away from the first base member of the first adjustable bleed valve 10, wherein the distance d is less than the first distance d1. Consequently, the throttling member 50 covers a greater portion of the plurality of bleed flow throttling openings 11b on the first bleed valve member 11.

[0133] In FIG. 5c, the first adjustable bleed valve 10 is in the second open state O2, at which state the first adjustable bleed valve 10 throttles the bleed flow in the piston rod 110 more than in the first open state O1. The first longitudinal end 50a of the throttling member 50 is at a position where it is a second distance d2 away from the first base member of the first adjustable bleed valve 10, which second distance d2 is less than the distance d. Consequently, the throttling member 50 covers an even greater portion of the plurality of bleed flow throttling openings 11b on the valve member 11.

[0134] Depending on the damping fluid pressure, the rebound check valve spring 32 may be unable to withstand the resulting force acting on the exposed area A30 of the rebound check valve cap 31 due to the bleed flow pressure. Hence, the rebound check valve 30 may open at the predetermined opening pressure level, as shown in FIG. 5d, thereby allowing a portion of the bleed flow to flow along the auxiliary rebound flow path P.sub.R through the central opening 12a of the first adjustable bleed valve 10, thereby relieving the pressure of the bleed flow.

[0135] FIGS. 6a, 6b show the working principle of the adjustable bleed valve assembly 1 according to one embodiment of the disclosure, as seen in cross sectional view. As is shown in FIG. 6, the bleed flow path P is as follows: starting from the compression chamber opening 110a, it continues into the second cylindrical cavity of the first base member 12, then continues through the bleed flow channels 12c, then along the piston bleed flow channel, then the bleed flow path P continues into the one or more bleed flow throttling openings 11b and through the bleed flow opening 11a into the throttling member 50. The bleed flow path P then continues into the bleed flow opening 21a of the second bleed valve member 21 into the second bleed valve member 21, then through the one or more bleed flow throttling openings 21b, through the bleed flow openings 130a of the first coupling member and then finally through the rebound chamber openings 110b.

[0136] During a compression stroke, the damping fluid flows as shown in FIG. 6a. During a rebound stroke, the damping fluid flows as shown in FIG. 6b. Moreover, the auxiliary rebound flow path P.sub.R is shown in FIG. 6a. The auxiliary rebound flow path P.sub.R is as follows: starting from the central opening 12a of the first adjustable bleed valve 10, it continues into the first cylindrical cavity of the first base member 12, then continues through the auxiliary flow path openings 12b and then joins the bleed flow path P.

[0137] Moreover, the auxiliary compression flow path P.sub.C is shown in FIG. 6b. The auxiliary compression flow path P.sub.C is as follows: starting from the central opening 22a of the second adjustable bleed valve 20, it continues into the single cylindrical cavity of the second cavity 22, then continues through the auxiliary flow path opening 22b and then joins the bleed flow path P.

[0138] FIG. 7 shows a portion of a shock absorber, comprising an adjustable bleed valve assembly 1, according to one embodiment of the disclosure. The bleed valve assembly 1 is arranged in the bleed flow channel of the piston rod 110 and operates during compression strokes and rebound strokes as herein previously discussed in relation to the FIGS. 1-6b. The first adjustable bleed valve 10 is adjusted between the first open state O1 and the second open state O2 by moving the first coupling member 130 in a longitudinal direction, either away from or toward the first adjustable bleed valve 10. The second adjustable bleed valve 20 is adjusted between the first open state O1 and the second open state O2 by moving the second coupling member 140 in a longitudinal direction along the longitudinal axis L, either away from or toward the throttling member 50.

[0139] FIG. 8 shows a cross sectional view of adjustment means, also referred to as “adjustment device,” for adjusting the adjustable bleed valve assembly 1 according to one embodiment of the disclosure. The adjustment means comprise a first coupling sleeve 131, a second coupling sleeve 142, and an intermediate coupling sleeve 143, and an adjustment rod 141, which are all, at least partly, arranged inside the first coupling member 130.

[0140] Starting with the first coupling sleeve 131, it is arranged to rotate about the longitudinal axis L to rotatably engage with the first coupling member 130. They do so by means of screw threads 131a and corresponding screw grooves. When rotating the first coupling sleeve 131 about the longitudinal axis L relative the piston rod, the first coupling sleeve 131 is screwed into or out of the first coupling member 130, depending on direction. Moreover, the first coupling sleeve 131 is rotatably arranged in the piston rod 110 at a fixed longitudinal position, by means of protrusions 1311, 1312, 1313 which engage with corresponding cavities in the piston rod 110. By this. the first coupling member 130 consequently moves along the longitudinal axis L, in an upward or downward direction as seen in FIG. 8, when rotating the first coupling sleeve 131. Hereby, the throttling member 50 of the adjustable bleed valve assembly 1 is adjusted in position which in turn affects the throttling of the first adjustable bleed valve 10.

[0141] The adjustment rod 141 is arranged to rotatably engage with the second coupling means 140, also referred to as “second coupling device 140,” by means of screw threads 131a and corresponding screw grooves (not shown in FIG. 8). Moreover, the adjustment rod 141 extends through the first coupling sleeve 131 and is adapted to freely rotate about the longitudinal axis L without causing the first coupling sleeve 131 to rotate relative the piston rod 110. Hence, when rotating the adjustment rod 141 about the longitudinal axis L, the second bleed valve member 21 is adjusted in position relative the throttling member, thereby adjusting the throttling of the second adjustable bleed valve 20.

[0142] Moreover, the adjustment means are further adapted to provide predetermined incremental step of adjusting the first adjustable bleed valve 10 and the second adjustable bleed valve 20. This is achieved by the adjustment means as shown in FIG. 8 in the following way.

[0143] The adjustment rod 141 and the second coupling sleeve 142 are rotatably locked with one another by means of a pin 1421 which is arranged to extend through the second coupling sleeve 142 and the adjustment rod 141. Moreover, due to the damping fluid pressure, which in some embodiments may be about 12 bar, the adjustment rod 141 is pushed into a downward direction, in other words, it is in a sense “spring”-biased in a downward direction as seen in FIG. 8.

[0144] Also, in-between the first coupling sleeve 131 and the second coupling sleeve 142, the intermediate coupling sleeve 143 is arranged. The intermediate coupling sleeve 143 is adapted to be rotationally interlocked with the first coupling member 130, while also being adapted to slide relative the first coupling member 130 along the longitudinal axis L. This is achieved by providing the intermediate coupling sleeve with two opposing flat surfaces 143a 143b which engage with corresponding flat inner wall portions of the first coupling member 130.

[0145] The intermediate coupling member 143 is adapted to releasably engage with the first coupling sleeve 131 and the second coupling sleeve 142 by means of a plurality of protrusions 1431, 1432 adapted to engage with corresponding cavities 1311, 1422 located on the first coupling sleeve 131 and the second coupling sleeve 142, respectively. This in combination with the spring-biased adjustment rod 141 establishes the incremental step function. When rotating the first coupling sleeve 131 about the longitudinal axis L, the intermediate coupling sleeve 143 is pushed upward as the first coupling sleeve 131 disengages with the intermediate coupling sleeve, which in turn causes the second coupling sleeve 142 and the adjustment rod 141 in an upward direction also, until the protrusions 1432 of the intermediate coupling sleeve 143 engages with a new set of cavities of the cavities 1311 of the first coupling sleeve 131. Likewise, when rotating the adjustment rod 141 and the second coupling sleeve 142, the adjustment rod 141 is pushed upward as the second coupling sleeve 142 disengages from the intermediate coupling sleeve 143, until the protrusions 1431 of the intermediate coupling sleeve 143 engages with a new set of cavities of the cavities 1422 of the second coupling sleeve 142.

[0146] FIG. 9 shows a block diagram of the disclosure disclosed herein according to one embodiment thereof. As previously explained, the bleed valve assembly 1 comprises a first adjustable bleed valve 10 and a second adjustable bleed valve 20. The bleed valve assembly 1 may be incorporated into a shock absorber 100 as previously explained. The first adjustable bleed valve 10 is adjustable from a distance by means of a first coupling member 130. The second adjustable bleed valve 140 is adjustable from a distance by means of a second coupling member 140. A first adjusting means 150, also referred to as “first adjusting device 150,” is coupled to the first adjustable bleed valve 10 by means of the first adjusting means 150. A second adjusting means 160, also referred to as “second adjusting device 160,” is coupled to the second adjustable bleed valve 20 by means of the second adjusting means 160. By controlling the first adjusting means 150, the first coupling member 130 can be controlled so as to adjust the first adjustable bleed valve 10 between the first open state O1 and the second open state O2. Likewise, by controlling the second adjusting means 160, the second coupling member 140 can be controlled so as to adjust the second adjustable bleed valve 20 between the first open state O1 and the second open state O2. The first coupling member 130 and the second coupling member 140 may be incorporated into the shock absorber 100. The first adjusting means 150 and the second adjusting means 160 may be incorporated into the shock absorber. The first adjusting means 150 and the second adjusting means 160 may be incorporated into an adjustment device 170. The first adjusting means 150 and the second adjusting means 160 may be worm wheels fixated to the first coupling member 130 and the second coupling member 140. The adjustment device 170 may comprise independent rotatable member for engaging with the first adjusting means 150 and the second adjusting means 160, which rotatable members may be accessible from an outside of the adjustment device 170.

[0147] The adjustable bleed valve assembly 1 may be adjustable in terms of compression damping parameter C and rebound damping parameter R, which are related to the level of throttling of the first adjustable bleed valve 10 and the second adjustable bleed valve 20. A lower value of said compression damping parameter C and rebound damping parameter R indicates an increased throttling of the damping fluid in compression and rebound respectively. Hence, by adjusting the throttling of the first adjustable bleed valve 10 and/or the second adjustable bleed valve 20, the compression damping parameter C and/or the rebound damping parameter R consequently changes.

[0148] FIG. 10 shows damping force characteristics during compression strokes and rebound strokes in relation to different values of compression damping parameter C while the rebound damping parameter R is held constant, specifically having R=12. The horizontal axis represents the piston rod velocity in m/s. The vertical axis represents the damping force in N.

[0149] Two groups of curves are shown in FIG. 10, a lower group and an upper group. The lower group represents compression damping force characteristics for different values of compression damping parameter C. The relationship between piston rod velocity and damping force is shown for the following values of compression damping parameter C: 15, 2; 15, 4; 15, 8; 15, 14; and 15, 24. As can be seen in FIG. 10, the damping force varies for the different values of the compression damping parameter C.

[0150] The upper group represents the rebound damping force characteristics for different values of compression damping parameter C and rebound damping parameter R. The relationship between piston rod velocity and compression damping force is shown for the following values of compression damping parameter C: 15, 2; 15, 8; and 15, 24. As can be seen in FIG. 10, although compression damping force characteristics have been adjusted, the rebound damping force characteristics does not change in any significant way.

[0151] In a similar manner, the FIG. 11 shows damping force characteristics during compression strokes and rebound strokes while the compression damping parameter C is held constant, specifically having C=15, 12. As before, the horizontal axis represents the piston rod velocity in m/s. The vertical axis represents the damping force in N.

[0152] Two groups of curves are shown in FIG. 11, a lower group and an upper group. The upper group represents the rebound damping force characteristics for different values of rebound damping parameter R. The relationship between piston rod velocity and rebound damping force is shown for the following values of rebound damping parameter R: 2, 4, 8, 14, and 24. As can be seen in FIG. 11, the rebound damping force varies for the different values of the rebound damping parameter R. The lower group represents the compression damping force characteristics for different values of rebound damping parameter R. The relationship between piston rod velocity and compression damping force is shown for the following values of rebound damping parameter R: 2; 8; and 24. As can be seen in FIG. 11, although rebound damping force characteristics have been adjusted, the compression damping force characteristics does not change in any significant way.

[0153] Hence, the adjustable bleed valve assembly of the present disclosure enables, be means of the two serially adjustable bleed valves, adjustment of compression damping force without impacting the rebound damping force in any significant way. Likewise, it enables adjustment of rebound damping force without impacting the compression damping force in any significant way.

[0154] FIG. 12 shows a method M100 for adjusting the adjustable bleed valve assembly 1 according to one embodiment of the disclosure. The method M100 comprises a step M101 of actuating at least one of the first and second adjustable bleed valves 10, 20 between the first open state O1 and the second open state O2, or between an open state O1, O2 and a closed state, so as to achieve a desired damping force characteristic during compression strokes and/or rebound strokes. Both the first and second adjustable bleed valves 10, 20 between the first open state O1 and the second open state O2, or between an open state O1, O2 and a closed state, respectively, so as to achieve a desired damping force characteristic during compressions strokes and/or rebound strokes.

[0155] Furthermore, the method M100 comprises a step M102 of actuating the first and second adjustable bleed valves 10, 20 between the first open state O1 and the second open state O2, or between an open state O1, O2 and a closed state, respectively, independently from each other.

[0156] The method M100 comprises a step M103 of moving a throttling member 50 relative a first bleed valve member 11 of the first adjustable bleed valve 10 so as to adjustably cover at least a portion of one or more bleed flow throttling openings 11b associated with the first adjustable bleed valve 10.

[0157] The method M100 comprises a step M104 of moving a second bleed valve member 21 of the second adjustable bleed valve 20 relative the throttling member 50 so as to adjustably cover at least a portion of one or more bleed flow throttling openings 21b associated with the second adjustable bleed valve 20. The method M100 comprises a step M105 of holding the throttling member 50 fixed relative the first bleed valve member 11 of the first adjustable bleed valve 10 when adjusting the second adjustable bleed valve 20.

[0158] The method M100 comprises a step M106 of holding the second bleed valve member 21 fixed relative the throttling member 50 when adjusting the first adjustable bleed valve 10.

[0159] The method M100 comprises a step M107 of opening a compression check valve at a predetermined damping fluid pressure.

The method M100 comprises a step M108 of opening a rebound check valve at a predetermined damping fluid pressure.

[0160] In the drawings and specification, there have been disclosed example embodiments and examples of the disclosure and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation, the scope of the disclosure being set forth in the following claims.