DESC:FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules, 2005

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

TITLE OF THE INVENTION
“MULTISTAGE DAMPING CONTROL SYSTEM FOR SHOCK
ABSORBER OF A TWO WHEELER”

Endurance Technologies Limited
E-92, M.I.D.C. Industrial Area, Waluj,
Aurangabad – 431136, Maharashtra, India

The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed.

Field of Invention

[001] The present invention is related to a shock absorber in a two wheeled vehicle. More particularly, the invention is related to a multistage damping control system for shock absorber of a two wheeled vehicle wherein the damping is automatically adjusted in a stage manner by the system based on the user input in the running condition of the vehicle.

Background of the Invention

[002] A two-wheeler shock absorber is generally mounted at the rear wheel of a vehicle. A shock absorber typically comprises an outer tube and a piston rod. The piston rod is positioned within said outer tube and is movable in both a compression stroke and an extension stroke. An orifice is provided in the piston. The motion of the piston causes a high viscosity fluid to pass through the orifice as the piston moves in order to provide the necessary damping. The shock absorbers typically have an oil filled outer tube within which the piston is mounted. However, the above mentioned arrangements of the shock absorber is not suitable for adjusting the damping as per user requirement.

[003] In order to solve the above-mentioned lacuna, a hollow piston rod with an orifice is designed for shock absorber. The said hollow piston rod is configured to accommodate a needle, where one end of the needle has a conical profile and the other end of the needle has a cylindrical profile. The conical-profiled needle end is provided at the piston side, and the cylindrical-profiled end is provided at the eyelet side. The said cylindrically profiled end of the needle is connected to the damping adjustment knob in the eyelet assembly of the shock absorber. The damping adjustment knob is accessible to the user for adjusting the damping orifice by up-down movement of the needle. Thereby, the user can rotate the damping adjustment knob as per the damping requirement.

[004] In some of the solutions, the required damping characteristics of the shock absorber are achieved by rotating the preload adjuster in a clockwise or counter-clockwise direction. In the aforementioned solutions, the required damping characteristics of the shock absorber are achieved by manual operations.

[005] However, none of the prior art provides an easy and multistage damping control system that automatically adjusts the desired damping under different road conditions based on the user input in the running condition of the vehicle. Hence, there is a long-pending and unmet need of a product that addresses the drawbacks of the conventional designs of the damping control system and provides a simple, economic, and maintenance free solution. The present invention, as described below, fulfills the requirement.

Objectives of the Invention

[006] The main object of the present invention is to provide a multistage damping control system for shock absorbers of a two wheeled vehicle.

[007] Another objective of the present invention is to provide a multistage damping control system for shock absorbers of a two wheeled vehicle wherein the system of the invention facilitates the user to go for multistage damping in running condition of the vehicle depending upon the road condition for a better ride and comfort.

[008] Further, the objective of the present invention is to provide a multistage damping control system for shock absorbers of a two wheeled vehicle wherein the encoder of the system being inbuilt with the motor housing not only reduces the uncertainty of the system but makes the system compact.

[009] The objective of the present invention is to provide a multistage damping control system for shock absorbers of a two wheeled vehicle wherein the system provides better noise, vibration and harshness characteristics and imparts improved reliability.

[0010] Yet, the objective of the present invention is to provide a multistage damping control system for shock absorbers of a two wheeled vehicle wherein the system wherein the damping control system is compact, simple in construction and cost effective.

[0011] Still another objective of the present invention is to provide a multistage damping control system for shock absorbers of a two wheeled vehicle wherein the system is configured to run fault detection loop and indicate the same to the use on the user interface.

Brief Description of the Drawings

[0012] This invention is illustrated in the accompanying drawings, throughout which like reference letters / numerals indicate corresponding parts in the various figures. The embodiments herein and advantages thereof will be better understood from the following description when read with reference to the following drawings, wherein

[0013] Figure 1 discloses the multistage damping control system for shock absorber of a two wheeler in accordance with the present invention.

[0014] Figure 2 shows an isometric view of the shock absorber of the multistage damping control system as per the present invention.

[0015] Figure 3 shows cut view of the shock absorber of the multistage damping control system in accordance with the present invention.

[0016] Figure 4a presents the cut view of the uniquely profiled wedge mounted on the D-profiled output shaft of the motor as per the present invention.

[0017] Figure 4b presents is the enlarged view of the rod link of the shock absorber disclosing the uniquely profiled cavity therein as per the present invention.

[0018] Figure 4c is the enlarged view of the rod link of the shock absorber disclosing the wedge mounted on the output shaft of the motor and housed in the profiled cavity of the rod link as per the present invention.

[0019] Figure 4d shows the enlarged view of the oil flow passage at the needle and split extension in the shock absorber making hydraulic communication between the compression chamber and rebound chamber in accordance with the present invention.

[0020] Figures 5a and 5b show the different isometric views of the wedge of the shock absorber in accordance with the present invention.

[0021] Figures 6a and 6b show the different isometric views of the motor of the shock absorber in accordance with the present invention.

[0022] Figure 7a shows the enlarged view of the rod link of the shock absorber disclosing the wedge at its home position; and the Figure 7b shows the enlarged view of the needle in the oil flow passage in completely closed condition as per the present invention.

[0023] Figure 8a shows the enlarged view of the rod link of the shock absorber disclosing the wedge in the middle position; and the Figure 8b shows the enlarged view of the needle in the oil flow passage in partially opened condition as per the present invention.

[0024] Figure 9a shows the enlarged view of the rod link of the shock absorber disclosing the wedge at its end position; and Figure 9b shows the enlarged view of the needle in the oil flow passage in completely opened condition as per the present invention.

Detailed Description of the Present Invention

[0025] The invention will now be described in detail with reference to the accompanying drawings which must not be viewed as restricting the scope and ambit of the invention. The multistage damping control system (1000) for a shock absorber of a two wheeler in accordance with the present invention comprises of a shock absorber (60), a wedge (70), a motor (50), an encoder (40), an electronic control unit (ECU) (20), a user interface (10), communication modules (12), and an ignition switch (30).

[0026] The said shock absorber (60) comprises of a rod link (65), an outer tube (75), an inner tube (78), a piston rod (80), a pre-load adjuster (85), a canister body (90), two springs (K1 and K2), an upper spring locator (95U), and a lower spring locator (95L). The said piston rod (80) is configured to be hollow creating a concentric passage (81) throughout the axial length of the piston rod (80), a lower end (80L) and an upper end (80U). The said concentric hole (81) of the piston rod (80) is configured to have a stepped profile near to the lower end (80L) of the piston rod (80).

[0027] The outer periphery of the lower end (80L) of the piston rod (80) is configured to have a plurality of threads for mounting a piston assembly (PA). A rebound spring (RA) is provided above the piston assembly (PA) and sleeved over the piston rod (80) of the shock absorber in such a way that it rests between the lower face of rod guide (80G) and the upper face of the piston assembly (PA). The said piston assembly (PA) and rebound spring (RA) of the piston rod (80) is slidably positioned inside the inner tube (78). The inner tube (78) is filled with working fluid and the lower end the said tube (78) is fitted with canister body (90) through a suitable fastening means. Further, the outer tube (75) is coaxially positioned over the said inner tube (78) and the bottom end of the outer tube (75) is fixed with the canister body (90) through a suitable fastening means. A coaxial gap is created between the outer periphery of the inner tube (78) and inner periphery of the outer tube (75), which is filled with a gas or fluid. After filling the gas or fluid inside the outer tube (75) and the inner tube (78), the upper end of the both tubes (75 and 78) are closed by sealing assembly and a sticker cap. The said sealing assembly is sleeved over the piston rod and fitted within the outer tube whereas the sticker cap is sleeved over the outer tube (75).

[0028] The pre-load adjuster (85) is placed over the outer tube (75) in such a way that the step profile of the adjuster (85) will rest over the lugs of the canister body (90). The lower spring locator (95L) is placed over the pre-load adjuster (85). The springs (K1 and K2) are encircled over the outer tube (75) and piston rod (80) in a series and are separated by a spring seat (KS). Thus, the spring (K1) is positioned in between the spring seat (KS) and the lower spring locator (95L) whereas the spring (K2) is positioned in between the spring seat (KS) and the upper spring locator (95U) which is fitted with the rod link (65).

[0029] The concentric passage (81) of the piston rod (80) is configured to accommodate a needle (98), where the said needle is a solid circular bar and is configured to have an upper end (98U) and a lower end (98L). The upper end (98U) of the needle (98) is configured to have a chamfered profile (98C). The chamfered profile (98C) of the needle (98) is configured to have an angle (a), where the said angle (a) is in the range of 20 degrees to 45 degrees. The lower end (98L) of the needle (98) is configured to have a conical profile (CP). The adaptor (A) of the piston assembly (PA) inserted into the stepped profile of the piston rod (80) narrows down the concentric passage (81) so as to make the movement of the conical profile (CP) of the needle (98) therein while restricting the needle (98) to enter therein. Further, the upper end (80U) of the piston rod (80) is connected with the rod link (65) of the shock absorber with the threaded joinery.

[0030] The rod link (65) of the shock absorber is configured to have an eyelet (65E), a threaded opening (66), a uniquely profiled cavity (67) and two projections (68). The said eyelet (65E) is provided at the upper side of the rod link (65) for mounting the shock absorber to the body/chassis of the two wheeled vehicle. The threaded opening (66) is provided in the lower face of the rod link (65) and said threaded opening (66) is in communication with the profiled cavity (67) through a passage (66P). The threaded opening (66) facilitates the fixing of the upper end (80U) of the piston rod (80) with the rod link (65) through a threaded joinery.

[0031] The uniquely profiled cavity (67) carved inside the rod link (65) has three steps (C1, C2 and C3) in a series to jointly accommodate the uniquely profiled wedge (70) (refer Figs. 4b and 4c). The first step (C1), having its distal end closed, is configured to have threads on its inner peripheral surface. The second step (C2), having diameter greater than the diameter of the first step (C1) but less than the diameter of the third step (C3), is sandwiched between the steps (C1 and C3). The step (C2) of the profiled cavity (67) is in communication with the threaded opening (66) through the passage (66P). The third step (C3) of the cavity (67), at its inner end is in communication with the second step (C2) and its outer end is extended out open on the outer periphery of the rod link (65). All the three steps (C1, C2 and C3) of the uniquely profiled cavity (67) of the rod link (65) are coaxial.

[0032] The two projections (68) extended out on the outer peripheral surface of the link (65) are in opposite directions from each other having their axes perpendicular to the axis of the cavity (67). The said projections are provided for mounting the motor (50) on the rod link (65) of the shock absorber (60).

[0033] The uniquely profiled wedge (70) is configured to have dumbbell shaped profile with three sections (S1, S2, S3). The first section (S1) have a cylindrical solid profile with the threads on its outer peripheral surface and the length (L1) of said first section (S1) is mandatorily less than the length of the first step (C1). The second section (S2) has a profile of shaft and is perpendicularly connected with the first section (S1) at its inner flat face. The diameter of the second section (S2) is less than the diameter of the first section (S1). The third section (S3) is configured to have cylindrical profile and is connected with the second section (S2) through a ramp profile (R). The diameter of the third section (S3) is greater than the diameter of the first step (C1) of the cavity (67) of the rod link (65) but less than the diameter of the second step (C2). Thus, the three sections (S1, S2, S3) coaxially integrated with each other forms a dumbbell shaped profiled wedge (70) as a single component.

[0034] The ramp profile (R) diverges from the end of the second section (S2) to join with the third section (S3) and said divergence form an angle (ß) with respect to the central axis of the wedge (70). The said angle (ß) of the divergence of the ramp profile (R) is in the range of 20 to 45 degrees. Further, the said ramp profile (R) is configured to divergence start point (a), divergence mid-point (b) and divergence end point (c).

[0035] The third section (S3), at its outer end, is provided with a flange (F) in such a way that the diameter of the flange (F) is greater than the diameter of second step (C2) of the cavity (67) of the rod link (65), but less than the diameter of the third step (C3). The unique design of the wedge (70) with the flange (F) restricts the axial movement of the wedge (70) after a predetermined limit within the profiled cavity (67). Further, the wedge (70) is provided with a groove (G) in the section (S3) from the flange side so as to receive the shaft (52) of the motor (50). The profile of the groove (G) is selected from the profiles of D-shape, I-shape, square, triangular and like any polygonal to have positive locking of the respective profiled shaft (52) of the motor (50) in the said groove (G).
[0036] During assembly of the wedge (70) inside the uniquely profiled cavity (67) of the rod link (65) of the shock absorber (60), the first section (S1) of the wedge (70) is threaded inside the first step (C1) of the cavity (67) of the rod link (65). As the length of the first step (C1) of the cavity (67) is greater than the length of first section (S1) of the wedge (70), a working space is created between the closed end of the first step (C1) and face of first section (S1). This working space allows the wedge (70) to have axial movement in forward direction or backward direction depending upon the rotational direction of the shaft of the motor.

[0037] The wedge (70) is positioned inside the cavity (67) in such a way that the needle (98) passing the passage (66P) is always in communication with the ramp profile (R). The chamfer profile (98C) provided at the upper end (98U) of needle (98) makes a contact surface with the ramp profile (R) and said contact surface (S) is configured to travel from divergence start point (a) to divergence end point (c) over the ramp profile (R) of wedge (70) and vice-versa depending on the direction of rotation of the wedge (70).

[0038] When the chamfer profile (98C) of the upper end of the needle (98) is in contact with divergence end point (c) on the ramp profile (R) of the wedge (70), the conical profile (CP) at the lower end of the needle (98) completely closes the fluid passage (81) by abutting the conical profile (CP) over the opening of the adaptor (A) of the piston assembly (PA) blocking the flow of the working fluid from the working chamber (below the piston assembly (PA)) in the inner tube to the rebound chamber through the orifices provided on the piston rod. This condition will lead the shock absorber under high damping zone (sports mode). When the chamfer profile (98C) of the upper end of the needle (98) is in contact with divergence mid-point (b) of the ramp profile (R) of the wedge (70), conical profile (CP) at the lower end of the needle (98) partially opens the fluid passage (81) thereby restricting the flow of the working fluid from the working chamber (below the piston assembly (PA)) to the rebound chamber. At this time, the shock absorber will go under mean damping zone (normal mode). When the chamfer profile (98C) at the upper end of the needle (98) is in contact with divergence start point (a) of the ramp profile (R) of the wedge (70), the conical profile (CP) at the lower end of the needle (98) completely opens the fluid passage (81) thereby making the free flow of the working fluid from the working chamber (below the piston assembly (PA)) to the rebound chamber without any restriction. This condition will lead the shock absorber to go under low damping zone (comfort mode).

[0039] The motor (50) is a geared DC motor and is configured to have a main body (50M), a gear box (51) and an output shaft (52). The gear box (51) provided for the protection of the gear arrangement which is connected rotating shaft of the motor (50). The said gear box (51) is configured to have two projected arms (51A) for mounting the motor (50) with respective projections (68) of the rod link (65) of the shock absorber (60). The output shaft (52) of the motor (50) projects out from the face of the gear box (51) of the motor (50). The profile of the shaft (52) of the motor (50) is selected from the profiles of D-shape, I-shape, square, triangular and like any polygonal to have positive locking of the respective profiled groove (G) of the wedge (70) with the said shaft (52).

[0040] The shaft (52) of the motor (50) is fitted in the groove (G) in such way that the groove (G) of the wedge (70) locks the said wedge (70) with the shaft (52) of the motor (50). The housing of the motor (50) houses an encoder (40) and said encoder (40) is configured to receive feedback of the axial travel of the wedge (70), information of the speed of the motor shaft rotation and the direction of rotation (clockwise or anticlockwise) of the motor shaft. Further, the encoder (40) with this feedback is in continuous communication with the ECU (20) through the communication modules (12).

[0041] The said encoder (40) and the motor (50) are in communication with the electronic control unit (20) through the communication modules (12). The communication modules (12) are selected from a group of wired communication, wireless communication and/or combination thereof. Further, the said electronic control unit (20) is in communication with the user interface (10) and the ignition switch (30) through the communication modules (12). The ignition switch (30) is connected with a battery. The user interface (10) is configured to receive the user inputs about damping adjustment and it is mounted on the handle bar of the vehicle.

[0042] The electronic control unit (20) is powered for its operation by the battery of the vehicle via the ignition switch (30). The electronic control unit (20) is configured to receive inputs from the user interface (10) and the encoder (40), process it and accordingly trigger the motor to run depending on the user input. The said electronic control unit (20) is mounted within the body of the vehicle at suitable location, preferably beneath the seat of the vehicle; and the said user interface (10) is mounted on the handlebar of the vehicle in such way that it is easily accessible by the user.

[0043] When the ignition of the vehicle is switched ON by inserting the key therein, the electronic control unit (20) of the damping control system gets activated and takes the system in calibration mode automatically. In the calibration mode of the system, the electronic control unit (20) commands the motor (50) to get back the wedge (70) in its home position i.e. the condition when the chamfer profile (98C) at the upper end of the needle (98) is in contact with divergence end point (c) on the ramp profile (R) of the wedge (70) and the conical profile (CP) at the lower end (98L) of the needle (98) is in complete closed condition where the fluid passage (81) will be completely blocked. Once the calibration mode is completed, the electronic control unit (20) receives the input of the user interface (10) and actuate the system to adjust the desired damping as per the user requirement.

[0044] Further, the electronic control unit (20) is configured to detect the back electromotive force (emf) which is generated by the motor (50). The back electromotive force (emf) in the motor will only generate in the case when the linear movement of the wedge (50) will try to exceed the threshold value. In the case, when the back electromotive force (emf) is generated by the motor (50) then the said back EMF action is recorded by the electronic control unit (20) and then, the ECU (20) commands the motor (50) for the operation of the calibration thereby moving the wedge (70) at its home position. Once the operation of the calibration is completed, the ECU (20) re-command the motor (50) for the movement of the wedge (70) as per the user requirement. When the above mentioned problem occurs in the second time, the electronic control unit (20) gives the feedback to the user interface (10) for indicating the message of repairing or servicing. The indication of the message of repairing or servicing of the damping control system is communicated to the user in the form of visual or audio indication or the combination of thereof on the user interface (10) through the communication modules (12). Thus, the architecture of the damping control system forms a closed loop control system where the ECU (20) gives the command to the motor (50) for linear movement of the wedge (70) after receiving the feedback from the user interface (10) and encoder (40) by using the communication module (12).

[0045] Further, the electronic control unit (20) of this closed loop control system is configured to run the fault loop continuously throughout the damping control system of the invention. If there is any fault in the system, the electronic control unit (20) captures the same and is being communicated to the user at the user interface (10) without interrupting the current working state of the system. This helps the user to an appropriate call of taking the vehicle to the service station / workshop.

[0046] Thus, in above described embodiment of the invention, the user interface (10) is configured to have sports mode, normal mode and comfort mode. The user may select the any of the three modes from the user interface (10) as per the damping requirement. In another embodiment, the user may control the opening of the fluid passage (81) in any position apart from the above mentioned three modes from the user interface (10) as per the damping requirement wherein the user interface (10) is selected from a group of TFT (Thin Film Transistor) display, and multiple position switches such as push button switch, rotary switch, and like.

[0047] As far as the working of this closed loop control system is concerned, when the rider puts the ignition switch (30) ON, the electronic control unit (20) gets activated and the multistage damping control system (1000) of the invention goes in calibration mode, that means the wedge (70) of the system is positioned at its home position i.e. the chamfer profile (98C) at the upper end of the needle (98) is in contact with divergence end point (c) on the ramp profile (R) of the wedge (70) and the conical profile (CP) at the lower end (98L) of the needle (98) is in complete closed condition.

[0048] Once the calibration mode is completed, the electronic control unit (20) receives the user input from the user interface (10), code it, process it and again decode it so as to trigger the motor to make the axial movement of the wedge. As per the input, the electronic control unit (20) triggers the motor (50) through the communication module to rotate in clock-wise or anti-clockwise rotation. As the motor (50) rotates in clockwise direction, the wedge (50) moves forward in axial direction; and during anti-clockwise rotation of the motor, the wedge (50) moves backward in the axial direction. This axial movement of the wedge (70) leads to the linear movement of the needle (98) within the piston rod (80) as the needle is in continuous mechanical communication with the wedge at its ramp profile (R). The linear movement (upward or downward direction) of the needle makes the conical profile (CP) at its the lower end (98L) to control the flow of working fluid from the opening of the fluid passage (81) of the piston rod (80). Thus the movement of the needle (98) controls the flow of the working fluid from the working chamber below the piston assembly (PA) to the rebound chamber of the shock absorber (60).

[0049] This results in setting the desired damping as per the mode selected by the rider / user i.e. sports mode, normal mode, and comfort mode. The encoder (40) continuously gives the feedback about the position of the wedge (70) and the needle (98) to the electronic control unit (20) and said electronic control unit (20) monitor and accordingly processes this feedback and communicates the set position of the damping at the user interface (10). The communication of said damping position by the electronic control unit (20) is in the form of visual or audio indication or the combination of thereof on the user interface (10).

[0050] The system of the present invention, in accordance with the discussed embodiments, provides the following technical advantages that contribute to the technical advancement of the multistage damping control system for the shock absorber of the present invention:
- The multistage damping control system of the invention facilitate the user to control the damping of the shock absorber based upon the road condition for a better ride and comfort.
- The present invention reduces the uncertainty of the damping control system by having closed loop feedback system by the encoder integrated with the motor housing.
- The system of the present invention facilitates the user to go for multiple damping adjustment in the running condition of the vehicle by using closed loop control system.
- The multistage damping control system of the present invention is intelligent enough to track the fault, if any, in the system and reciprocate with the user about the fault by giving audio or visual signal.
- The present invention provides better noise, vibration and harshness characteristics and imparts improved reliability.
- The system of the present invention is compact, easy to manufacture and cost effective.

[0051] The foregoing description of the specific embodiment of the invention will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein. ,CLAIMS:We Claim

1. A multistage damping control system (1000) for a shock absorber of a two wheeler comprising of a shock absorber (60) having the rod link (65), a wedge (70), a motor (50), an encoder (40), an electronic control unit (ECU) (20), a user interface (10), communication modules (12), an ignition switch (30) and a battery;
Wherein,
- the rod link (65) of the shock absorber (60) is configured to have a uniquely profiled cavity (67), a threaded opening (66) and two projections (68); and said threaded opening (66) provided in the lower face of the rod link (65) is in communication with the profiled cavity (67) through a passage (66P);
- the wedge (70) is configured to have a dumbbell shaped profile with three sections (S1, S2, S3) and a groove (G);
- the motor (50) is configured to have a main body (50M) housing a gear box (51) therein and an output shaft (52) projecting therefrom and is mounted on the projections (68) of the rod link (65);
- said wedge (70) is mounted on the output shaft (52) of the motor in such a way that the said wedge is housed in the profiled cavity (67) of the rod link (65);
- said motor (50) having an integrated encoder (40) therein is in communication with the ECU (20) and said ECU (20) is in communication with the battery via ignition switch (30) through the communication modules (12); and
- the user interface (10) is mounted on the handlebar of the vehicle and is in communication with said ECU (20) through the communication module (12) forming the closed loop multistage damping control system for a shock absorber.

2. The multistage damping control system (1000) for a shock absorber as claimed in claim 1, wherein
- the uniquely profiled cavity (67) carved inside the rod link (65) has three steps (C1, C2 and C3) in a series to jointly accommodate the uniquely profiled wedge (70);
- the first step (C1), having its distal end closed, is configured to have threads on its inner peripheral surface;
- the second step (C2), having diameter greater than the diameter of the first step (C1) but less than the diameter of the third step (C3), is sandwiched between the steps (C1 and C3); and
- the third step (C3) of the cavity (67), at its inner end is in communication with the second step (C2) and its outer end is extended out open on the outer periphery of the rod link (65).

3. The multistage damping control system (1000) for a shock absorber as claimed in claim 2, wherein
- the three steps (C1, C2 and C3) of the uniquely profiled cavity (67) of the rod link (65) are coaxial; and
- the step (C2) of the profiled cavity (67) is in communication with the threaded opening (66) through the passage (66P).

4. The multistage damping control system (1000) for a shock absorber as claimed in claim 2, wherein
- the first section (S1) of the wedge (70) has a cylindrical solid profile with the threads on its outer peripheral surface and the length (L1) of said first section (S1) is mandatorily less than the length of the first step (C1);
- the second section (S2) of the wedge (70) has a profile of shaft and is perpendicularly connected with the first section (S1) at its inner flat face and the diameter of said second section (S2) is less than the diameter of the first section (S1);
- the third section (S3) of the wedge (70) is configured to have cylindrical profile and is connected with the second section (S2) through a ramp profile (R) and the diameter of said third section (S3) is greater than the diameter of the first step (C1) of the cavity (67) of the rod link (65) but less than the diameter of the second step (C2) of the cavity (67) of the rod link (65); and
- said three sections (S1, S2, S3) are coaxially integrated with each other to form a dumbbell shaped profiled wedge (70) as a single unit.

5. The multistage damping control system (1000) for a shock absorber as claimed in claim 4, wherein
- the ramp profile (R) diverges from the end of the second section (S2) to join with the third section (S3) and said divergence forms an angle (ß) with respect to the central axis of the wedge (70); and
- said ramp profile (R) is configured to have divergence start point (a), divergence mid-point (b) and divergence end point (c).

6. The multistage damping control system (1000) for a shock absorber as claimed in claim 5, wherein said angle (ß) of the divergence of the ramp profile (R) is in the range of 20 to 45 degrees.

7. The multistage damping control system (1000) for a shock absorber as claimed in claim 4, wherein
- the third section (S3) of the wedge (70), at its outer end, is provided with a flange (F) in such a way that the diameter of the flange (F) is greater than the diameter of second step (C2) of the cavity (67) of the rod link (65), but less than the diameter of the third step (C3); and
- said wedge (70) is provided with a groove (G) in the section (S3) from the flange side so as to receive the shaft (52) of the motor (50).

8. The multistage damping control system (1000) for a shock absorber as claimed in claim 4, wherein the profile of the groove (G) is selected from the profiles of D-shape, I-shape, square, triangular and any polygonal to have positive locking of the respective profiled shaft (52) of the motor (50) in the said groove (G).

9. The multistage damping control system (1000) for a shock absorber as claimed in claim 7, wherein
- the first section (S1) of the wedge (70) is threaded inside the first step (C1) of the cavity (67) of the rod link (65); and
- the difference in the length of the first step (C1) of the cavity (67) and the length of first section (S1) of the wedge (70) creates a working space between the closed end of the first step (C1) and face of first section (S1); and said working space allows the wedge (70) to have axial movement in forward direction or backward direction depending upon the rotational direction of the shaft of the motor.

10. The multistage damping control system (1000) for a shock absorber as claimed in claim 9, wherein the rod link (65) of the shock absorber (60) is configured to have two projections (68) to mount the motor (50) and said projections (68) are extended out on the outer peripheral surface of said rod link (65) in opposite directions from each other having their axes perpendicular to the axis of the cavity (67).

11. The multistage damping control system (1000) for a shock absorber as claimed in claim 10, wherein
- the motor (50), having a main body (50M), output shaft (52) and a gear box (51) therein, is configured to have two projected arms (51A) for mounting the motor (50) with respective projections (68) of the rod link (65) of the shock absorber (60);
- the shaft (52) of the motor (50) is fitted in the groove (G) in such way that the groove (G) of the wedge (70) locks the said wedge (70) with the shaft (52) of the motor (50); and
- the profile of said output shaft (52) of the motor (50) is selected from the profiles of D-shape, I-shape, square, triangular and any polygonal to have positive locking of the respective profiled groove (G) of the wedge (70) with the said shaft (52).

12. The multistage damping control system (1000) for a shock absorber as claimed in claim 11, wherein
- the housing of the motor (50) houses an encoder (40) and said encoder (40) is configured to receive feedback of the axial travel of the wedge (70), information of the speed of the motor shaft rotation and the direction of rotation (clockwise or anticlockwise) of the motor shaft;
- said encoder (40) with this feedback is in continuous communication with the ECU (20) through the communication modules (12);
- said encoder (40) and the motor (50) are in communication with the electronic control unit (20) through the communication modules (12);
- the communication modules (12) are selected from a group of wired communication, wireless communication and combination thereof.

13. The multistage damping control system (1000) for a shock absorber as claimed in claim 12, wherein
- the electronic control unit (20) is in communication with the user interface (10) and the battery via the ignition switch (30) through the communication modules (12);
- the user interface (10) is configured to receive the user inputs about damping adjustment and it is mounted on the handle bar of the vehicle;
- said electronic control unit (20), powered for its operation by the battery of the vehicle via the ignition switch (30), is configured to receive inputs from the user interface (10) and the encoder (40), process it and accordingly trigger the motor to run depending on the user input;
- said electronic control unit (20) is mounted within the body of the vehicle beneath the seat of the vehicle; and the said user interface (10) is mounted on the handlebar of the vehicle in such way that it is easily accessible by the user; and
- said user interface (10) is configured to have sports mode, normal mode and comfort mode and said user interface (10) is selected from a group of TFT (Thin Film Transistor) display, and multiple position switches viz. push button switch, rotary switch, and like.

14. The multistage damping control system (1000) for a shock absorber as claimed in claim 13, wherein
- the electronic control unit (20) of the damping control system is configured to get activated so as to take the system in calibration mode automatically on switching ON the ignition of the vehicle by inserting the key therein;
- said electronic control unit (20) is configured to detect the back electromotive force (emf) which is generated by the motor (50) and give feedback to the user interface (10) for indicating the message of repairing or servicing in the form of visual or audio indication or the combination of thereof on the user interface (10) through the communication modules (12); and
- said electronic control unit (20) of the closed loop control system is configured to run the fault loop continuously throughout the damping control system of the invention and captures the same and is being communicated to the user at the user interface (10) without interrupting the working state of the system.

15. The multistage damping control system (1000) for a shock absorber as claimed in claim 14, wherein
- the concentric passage (81) of the piston rod (80) is configured to accommodate a needle (98), where the said needle is a solid circular bar and is configured to have an upper end (98U) and a lower end (98L);
- the upper end (98U) of the needle (98) is configured to have a chamfered profile (98C) and said chamfered profile (98C) of the needle (98) is configured to have an angle (a), where the said angle (a) is in the range of 20 degrees to 45 degrees;
- the lower end (98L) of the needle (98) is configured to have a conical profile (CP);
- the adaptor (A) of the piston assembly (PA) inserted into the stepped profile of the piston rod (80) narrows down the concentric passage (81) so as to make the movement of the conical profile (CP) of the needle (98) therein while restricting the needle (98) to enter therein; and
- the upper end (80U) of the piston rod (80) is connected with the rod link (65) of the shock absorber with the threaded joinery.

16. The multistage damping control system (1000) for a shock absorber as claimed in claim 15, wherein
- the wedge (70) is positioned inside the cavity (67) in such a way that the needle (98) passing the passage (66P) is always in communication with the ramp profile (R); and
- the chamfer profile (98C) provided at the upper end (98U) of needle (98) makes a contact surface with the ramp profile (R) and said contact surface (S) is configured to travel from divergence start point (a) to divergence end point (c) over the ramp profile (R) of wedge (70) and vice-versa depending on the direction of rotation of the wedge (70).

17. The multistage damping control system (1000) for a shock absorber as claimed in claim 16, wherein
- the said shock absorber (60) comprises of a rod link (65), an outer tube (75), an inner tube (78), a piston rod (80), a pre-load adjuster (85), a canister body (90), two springs (K1 and K2), an upper spring locator (95U), and a lower spring locator (95L);
- the said piston rod (80) is configured to be hollow creating a concentric passage (81) throughout the axial length of the piston rod (80), a lower end (80L) and an upper end (80U) and said concentric passage (81) of the piston rod (80) is configured to have a stepped profile near to the lower end (80L) of the piston rod (80);
- the outer periphery of the lower end (80L) of the piston rod (80) is configured to have a plurality of threads for mounting a piston assembly (PA);
- a rebound spring (RA) is provided above the piston assembly (PA) and sleeved over the piston rod (80) of the shock absorber in such a way that it rests between the lower face of rod guide (80G) and the upper face of the piston assembly (PA);
- the said piston assembly (PA) and rebound spring (RA) of the piston rod (80) is slidably positioned inside the inner tube (78);
- the inner tube (78) is filled with working fluid and the lower end the said tube (78) is fitted with canister body (90) through a suitable fastening means;
- the outer tube (75) is coaxially positioned over the said inner tube (78) and the bottom end of the outer tube (75) is fixed with the canister body (90) through a suitable fastening means;
- the upper end of the both tubes (75 and 78) are closed by sealing assembly and a sticker cap wherein said sealing assembly is sleeved over the piston rod and fitted within the outer tube whereas the sticker cap is sleeved over the outer tube (75);
- the pre-load adjuster (85) is placed over the outer tube (75) in such a way that the step profile of the adjuster (85) will rest over the lugs of the canister body (90);
- the lower spring locator (95L) is placed over the pre-load adjuster (85) and the springs (K1 and K2) are encircled over the outer tube (75) and piston rod (80) in a series and are separated by a spring seat (KS) in such a way that the spring (K1) is positioned in between the spring seat (KS) and the lower spring locator (95L) whereas the spring (K2) is positioned in between the spring seat (KS) and the upper spring locator (95U) which is fitted with the rod link (65).

Dated this 9th day of January 2024

Sahastrarashmi Pund
Head – IPR
Endurance Technologies Ltd.

To,
The Controller of Patents,
The Patent Office, at Mumbai.