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
“SEALING ASSEMBLY FOR EMULSION SHOCK ABSORBER OF A VEHICLE”

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

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

[001] The present invention relates to an emulsion shock absorber for two and three wheeled vehicles. More particularly, the present invention relates to a sealing assembly for the emulsion shock absorbers of two and three wheeled vehicles, wherein the sealing assembly is uniquely designed and configured to facilitate easy filling of the working fluid, particularly the gas, inside the working chamber of the shock absorber.

Background of the Invention

[002] A hydraulic shock absorber is generally classified as a mono tube shock absorber and a twin tube shock absorber based on its construction. The twin tube hydraulic shock absorber has an inner tube containing the sliding piston surrounded by an outer tube which forms the external body of the shock absorber. The inner tube and outer tube are separated by an annular space formed in between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube. The said inner tube is filled with oil, and the annular space created between the inner tube and the outer tube is sealed with air at the time of assembly. The heat produced inside the shock absorber causes the air inside the outer tube to expand leading to change in shock absorber characteristics and consequent hard feeling of the shocker.

[003] To address the above lacuna in the hydraulic shock absorbers, the emulsion shock absorbers are generally employed wherein the outer tube is filled with a nitrogen gas and the inner tube having the sliding piston assembly is filled with the working fluid, preferably the oil, and said inner tube is surrounded by the outer tube. In these shock absorbers, the sliding piston is connected with a piston rod which extends out from the inner tube. Further, the upper end portion of the inner tube and the outer tube is sealed by concentrically sleeving a rod guide and an oil seal over the piston rod. Then, a metal seal washer is sleeved over the piston rod on the oil seal for protecting the lips of the oil seal from the bump stop during full compression. The oil seal and the metal seal washer are secured inside the outer tube by crimping the upper end portion of the outer tube. In such arrangement, conventionally the nitrogen gas is filled through a gas injection hole which is purposely formed by drilling at one end of an outer tube of the shock absorber assembly. Once the nitrogen gas is filled inside the shock absorber, the gas injection hole is welded and sealed at the same time. However, this method of gas filling demands for drilling a separate hole for injecting gas into one end of the outer tube which causes the problem of damage to the outer tube, reducing the life of the shock absorber and increasing the cost. Further, this arrangement does not facilitate the refilling of the gas once the shock absorber is fitted on the vehicle.

[004] Therefore, to address the above issues of gas filling in emulsion shock absorbers, a gas filling and crimping setup came into existence. In this method, the seal is loosely position on the top of the rod guide of the shock absorber and then gas filling and crimping set up is positioned in the gap between the seal with seal washer and the inner surface of the outer tube for filling the nitrogen gas. The gas is being then forced from the source into the shock absorber from the top, allowing the gas to flow past the outer edge of the seal, through the rod guide, and into the gas chamber of the emulsion shock absorber. In this method, the upper edges of the outer tube need to be partially folded to prevent the seal from getting displaced due to the pressure being exerted by the gas inside the shock absorber. When the top edge of the outer tube is being folded, there is always the risk of the seal getting displaced from its position, leading to leakage of filled-up gas from the shock absorber. At this stage, it is extremely difficult to unfold the partially folded edges of the outer tube so as to reposition the seal and refill gas therein. Hence, this method of gas filling inevitably leads to process rejections in some cases.

[005] Therefore, to address the above mentioned drawbacks of the prior art, there is a requirement of providing an intelligent and uniquely designed sealing assembly that would provide leak-proof gas filling and enable nitrogen gas to get filled inside the shock absorber easily and repeatedly without requiring any skilled manpower.

Objectives of the Invention

[006] The main object of the present invention is to provide a sealing assembly for the emulsion type shock absorber of two and three wheeled vehicles.

[007] Another object of the present invention is to provide a sealing assembly for the emulsion shock absorber that facilitate to provide the space for easily mounting and receiving a gas filling tool.

[008] Yet another object of the present invention is to provide a sealing assembly for the emulsion shock absorber which facilitates leak-proof gas filling and the provision for repeatedly filling of gas without requiring any skilled manpower.

[009] Yet another object of the present invention is to provide a sealing assembly for the emulsion shock absorber which avoids the damage of oil seal lips during filling of the gas in the shock absorber.

[0010] Yet another object of the present invention is to provide a sealing assembly for the emulsion shock absorber that eliminates the misalignment of the seal, avoids the leakage of the gas and oil from the shock absorber and restrict the ingression of the dust and/or any foreign particles inside the shock absorber.

[0011] Yet the object of the present invention is to provide a sealing assembly that not only provides the required resting surface for the bump stop during compression stroke but provides better strength to sustain the impact load of the bump stopper during full compression stroke as well.

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 a front view of an emulsion shock absorber for a two and three wheeled vehicles in accordance with the present invention.

[0014] Figure 2 discloses a sectional view of the emulsion shock absorber for two and three wheeled vehicles in accordance with the present invention.
[0015] Figure 3 presents enlarged cut view of the emulsion shock absorber of the invention disclosing the sealing assembly as per the invention.

[0016] Figures 4 and 5 disclose an enlarged sectional view of the sealing assembly of the present invention is dismantled and assembled condition, respectively.

[0017] Figures 6a to 7b discloses the protection cap of the sealing assembly in accordance with the first embodiment of the present invention.

[0018] Figures 8a to 9b discloses the protection cap of the sealing assembly in accordance with the second embodiment of the present invention.

Detailed Description of the Present Invention

[0019] 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. In accordance with the disclosed embodiment of the present invention, an emulsion type shock absorber (1000) for two and three wheeled vehicles comprises of an inner tube (50), an outer tube (100), a sealing assembly (10), a coil spring (120), a piston rod (150), a piston and rebound stopper assembly (180), a bump stop (200), a dust cover (220), a spring locator (250), a U-bracket (280), a bottom cap (300), a cushioning rubber (350), and a nut (400).

[0020] The outer tube (100) is configured to have a cylindrical profile with an upper end (102) and a lower end (104). The said lower end (104) of the outer tube (100) is closed with the help of the bottom cap (300) in such a way the bottom cap (300) is sleeved inside the lower end (104) of the outer tube (100) followed by welding. The said bottom cap (300) is configured to have a bowl-shape. The base of the bowl-shape bottom cap (300) is fitted with the U-bracket (280) by the fixing means viz. welding, threading, etc. The said U-bracket (280) is used to connect the emulsion shock absorber (1000) with the wheel axle of the vehicle. Further, a fixed spring seat (115) is welded over the outer peripheral surface of the outer tube (100) and towards to lower end (104) of the outer tube (100).

[0021] The said inner tube (50) is configured to have a cylindrical profile with an upper end (52) and a bottom end (54). The said bottom end (54) of the inner tube is closed by press fitting a base valve assembly (60) therein. The said base valve assembly (60) is configured to restrict the oil from escaping when the piston and valve assembly is moving in the compression stroke. The outer diameter of the inner tube (50) is less than the inner diameter of the outer tube (100). Further, the length of the inner tube (50) is also less than the length of the outer tube (100). The inner tube (50) having base valve assembly (60) in the bottom end (54) is concentrically sleeved inside the outer tube (100) from the upper end (102) and abuts over the bowl-shape bottom cap (300). A gas chamber (70) is created along the outer peripheral surface of the inner tube (50) and the inner peripheral surface of outer tube (100) due to difference in the diameter of the outer tube (100) and the inner tube (50). After installing the inner tube (50) inside the outer tube (100), a gap (G) is created in between the top end (52) of the inner tube (50) and top end (102) of the outer tube (100) due to the difference in the longitudinal length of the inner tube (50) and the outer tube (100). The inner tube (50) is partially filled with oil for achieving damping characteristics.

[0022] The piston rod (150) is configured to have a piston and rebound stopper assembly (180) at one end of the piston rod (150). The said end of the piston rod (150) having piston and rebound assembly (180) is slideably positioned inside the inner tube (50). After positioning the piston and rebound stopper assembly (180), the seal assembly (10) is concentrically sleeved over the piston rod (150) and positioned in the between the gap (G) that is created between the top end (52) of the inner tube (50) and the top end (102) of the outer tube (100). The seal assembly (10) is positioned in the axial gap (G), by placing the protection cap (35) over the oil seal (25) followed by crimping an edge (102E) of the top end (102) of the outer tube (100) inwardly by a crimping set up. The crimping of the top end (102) of the outer tube (100) is used to secure and maintain the position of the sealing assembly (10). Further, the bump stop (200) is sleeved tightly over the piston rod (150) and is also spaced apart from the seal assembly (10).

[0023] The said coil spring (120) is sleeved over the outer tube (100) and abuts on the fixed spring seat (115). The dust cover (220) has an annular flange (222) and circular hollow body (224), where the circular body (224) of the dust cover (200) is positioned inside the coil spring (120) and have sufficient length to cover the piston rod (150) which is exposed to the environment, and the flange (222) of the dust cover (220) is positioned over the top end of the coil spring (120). After positioning of the dust cover (220), the spring locator (250) is positioned on the step profile (150S) of the piston rod (150). The spring locator (250) is configured to have a main body (250C) having a bowl shaped profile and an L-shaped annular flap (250F) extending around the main body (250C). The spring locator (250) is fitted with the piston rod (150) in such a manner that the inner surface of the main body (250C) of the spring locator (250) rests over the top surface of the bump stop (200) and the inner top surface of the flap (250F) rests over the top surface of the flange (222) of the dust cover (200). The said spring locator (250) is used to position the coil spring (120) under partial compressed load by using the nut assembly (400). The cushioning rubber (350) is provided between the nut assembly (400) and spring locator (250) to avoid the metal to metal contact.

[0024] The sealing assembly (10) comprises of a rod guide (15), an oil seal (25) and a protection cap (35). The said rod guide (15) have cylindrical multistep profile and is configured to have a main body (16), a central bore (17), a cavity (18), a seat (19), a groove (20), a plurality of channels (21) and a lower projection (22). The central bore (17) of the rod guide (15) is configured have a larger diameter than the outer diameter of the piston rod (150) and is configured to receive the piston rode (150). Further, a radial space (RS) is created between the outer periphery of the piston rod (150) and inner periphery of the central bore (17) of the rod guide, where the said radial space (RS) is configured to receive a bush (24) to avoid the friction during reciprocation of the piston rod (150). The cavity (18) is provided coaxially adjacent to the central bore (17) and is configured to receive a lip portion (31) of the oil seal (25). The seat (19) is an annular wall of the said cavity (18) which is projected towards top end of the rod guide (15).

[0025] The said seat (19) is configured to provide a rest position for the oil seal (25). The groove (20) is provided on the outer diameter of the seat (19) and is configured to receive a skirt lip (28) of the oil seal (25) for guiding the oil seal (25) with the rod guide (15) for better alignment of the oil seal (25). The lower projection (22) is projected downside from the main body (16) of the rod guide (15) and is configured to be interposed inside the inner tube (50) through transition fit. The bottom end of the outer periphery of the main body (16) and the top portion of the lower projection (22) are connected by an integral tapered portion (T). The channels (21) are cylindrical cavities thoroughly passing through the tapered portion (T) of the rod guide (15) and are formed diametrically opposite to each other. The said channels fluidly connect the cavity (18) and the gas chamber (70) and thus forms a passage for filling the nitrogen gas in the said gas chamber (70) of the shock absorber (1000).

[0026] The oil seal (25) comprises of a reinforcing metal insert (26) and a reinforcement ring (R). The said oil seal (25) is formed by over-molding the elastomeric material around the metal insert (26). The oil seal (25) forms a unique profile having a first seal lip (29), a second seal lip (30), a third seal lip (31), and a skirt lip (28).

[0027] The first seal lip (29) converges away from the inner edge of reinforcing metal insert (26). The second seal lip (30) also converges away from inner edge of reinforcing metal insert (26) but in a direction opposite to that of first seal lip (29). The third seal lip (31) converges away from the inner edge of reinforcing metal insert (26) but in the same direction as that of second seal lip (30). The reinforcement ring (R) is positioned in a recess formed around the third seal lip (31) of the seal (25) in order to apply radial load on the seal lip (31) thereby enhancing the sealing effect on the piston rod (150). The said seal lips (29, 30 and 31) are formed in a manner so as to allow the passage of the piston rod (150) while the lips deform around the said piston rod (150) to form gripping. The third seal lip (31) is configured to have maximum deformation around the piston rod (150) so as to create the perfect sealing effect.

[0028] The skirt lip (28) of the oil seal (25) is formed at outer periphery of the main rubber body (26) and projects downwards towards the inner diameter of outer tube (100). The said oil seal (25) is sleeved over the piston rod (150) and abuts over the said rod guide (15) in such manner that the said skirt lip (28) of the oil seal (25) is interposed in the groove (20) of the rod guide (15), and the middle lip (30) and the lower lip (31) are positioned inside the cavity (18) of the rod guide (15).

[0029] The protection cap (35) as per the first embodiment of the present invention (refer Figs. 6a - 7b) is configured to have a disc portion (35D) and a circumferential side wall (35W). The disc portion (35D) has a stepped profile having a flat base wall (36), a tapered wall (37) and a flat top wall (38) wherein the tapered wall (37) joins the flat base wall (36) and the flat top wall (38) to form the said disc portion (35D). The circumferential side wall (35W) projects in a downward direction from the base wall (36) in an integral manner. The top wall (38) has a central opening (35H) formed therein to allow the passage of the piston rod (150) therefrom. The base wall (36), tapered wall (37) and the top wall (38) of the disc portion (35D) has a uniform thickness across its upper side (35U) and lower side (35L) thus forms an annular body replicating the said portions to form the protection cap (35). The thickness of the circumferential wall (35W) is greater than the thickness of the disc portion (35D) of the protection cap (35).

[0030] The base wall (36) of the disc portion (35D) of the protection cap (35) facilitates to provide the resting for the crimped edge (102E) of the top end (102) of the outer tube (100). The tapered wall (37) is configured to have a taper angle (a) with respect to the base wall (36) wherein the said angle ranges from 25 to 35°. The taper angle (a) of the tapered wall (37) is in conformation with the profile of the first seal lip of the oil seal (25) and thus facilitates to protect the said lip from damage during assembly and working condition. The top wall (38) is configured to provide the resting surface for the bump stop (200) and thus helps in achieving the required bottoming load thereby during the extreme compression stroke of the shock absorber (1000).

[0031] The top wall (38) of the disc portion (35D) of the protection cap (35) is configured to have a central opening (35H) wherein the diameter (Dh) of the said opening (35H) is greater than the diameter (Dp) of the piston rod (150) in such a way that said opening (35H) is configured to form a radial gap (45) in between the outer peripheral surface of the piston rod (150) and the inner peripheral surface of the central opening (35H) of the protection cap (35). The said radial gap (45) is formed in a manner such that the ratio of the diameter (Dp) of piston rod (150) and the diameter (Dh) of the central opening (35H) of the protection cap (35) is in the range of 1:1.20 to 1: 1.25. The said radial gap (45) is configured to receive a gas filling tool for filling the gas inside the gas chamber (70) of the emulsion shock absorber (1000).

[0032] Further, the protection cap (35) of the sealing assembly (10) is configured to have a plurality of ribs (39) formed at its lower portion (35L). The said ribs (39) may vary from a minimum three to six ribs positioned at an equiangular distance to each other (refer Figs. 6a and 7a). The ribs (39) extends from the inner peripheral surface of the circumferential wall (35W) and flush to merge with the outer peripheral edge (38E2) of the inner top surface of the top wall (38). The ribs (39) are configured to have a curved ramp shaped profile having a first curved ramp (39A) and a second curved ramp (39B). The first curved ramp (39A) extends from the outer peripheral edge (38E2) of the inner top surface (38IT) of the top wall (38) to the mid segment (37M) of the tapered wall (37) and the second curved ramp (39B) extends from the mid segment (37M) of the tapered wall (37) to the inner peripheral surface of the circumferential wall (35W) of the protection cap (35).

[0033] The first ramp (39A) is configured to have a ramp angle (ß) with respect to the horizontal axis of the top wall (38) wherein the said angle (ß) ranges from 45 to 65°. The second ramp (39B) is configured to have a ramp angle (?) with respect to the horizontal axis of the base wall (36) wherein the said angle (?) ranges from 55 to 75°. The ribs (39) of the protection cap (35) facilitates to impart the required mechanical strength to withstand the impact load applied by the bump stop (200) during the extreme compressive stroke of the shock absorber (1000). Further, the unique ramp shape profile of the ribs (39) facilities the protection of the lips of the oil seal (25) during the assembly and working condition of the shock absorber.

[0034] The said ribs (39) are configured to have a thickness (t), where the said thickness (t) is in the range of 1.5 mm to 3 mm. The thickness (t) of the ribs (39) is configured to maintain the position of the oil seal (25) and avoid the damage of the lip and body of the oil seal (25) from the bump stop (200) during compression stroke.

[0035] As per the second embodiment of the present invention (refer Figs. 8a - 9b), the protection cap (35) is configured to have a plurality of ribs (39’) varying from a minimum four to six ribs positioned at an equiangular distance to each other. The said ribs (39’) extends from the inner peripheral surface of the circumferential wall (35W’) and flush to merge with the inner peripheral edge (38E1’) of the inner top surface of the top wall (38’). The ribs (39’) are configured to have a curved ramp shaped profile having a first curved ramp (39A’), a second curved ramp (39B’) and a third curved ramp (39C). The first curved ramp (39A’) extends from the inner peripheral edge (38E1’) of the inner top surface (38IT’) to the outer peripheral edge (38E2’) of the inner top surface (38IT’). The second curved ramp (39B’) extends from the outer peripheral edge (38E2’) of the inner top surface (38IT’) of the top wall to the outer peripheral edge of the tapered wall (37’) and the third curved ramp (39C) extends from the to the outer peripheral edge (37E2’) of the tapered wall (37) to the inner peripheral edge of the circumferential wall (35W’) of the protection cap (35).

[0036] The first ramp (39A’) is configured to have a ramp angle (ß’) with respect to the horizontal axis of the top wall (38’) wherein the said angle (ß’) ranges from 45 to 65°. The second ramp (39B’) is configured to have a ramp angle (?’) with respect to the horizontal axis of the base wall (36’) wherein the said angle (?’) ranges from 55 to 75°. The ribs (39’) of the protection cap (35) facilitates to impart the required mechanical strength to withstand the impact load applied by the bump stop (200) during the extreme compressive stroke of the shock absorber (1000). Further, the unique ramp shape profile of the ribs (39’) facilities the protection of the lips of the oil seal (25) during the assembly and working condition of the shock absorber.

[0037] During the positioning of the sealing assembly (10) within the shock absorber (1000), the seal assembly (10) is positioned in the gap (G) formed between the top end (52) of the inner tube (50) and the top end (102) of the outer tube (100). The oil seal (25) is sleeved over the piston rod (150) and abuts over the rod guide (15) in such manner that the said skirt lip (28) of the oil seal (25) is interposed in the groove (20) of the rod guide (15), and the middle lip (30) and the lower lip (31) are positioned inside the cavity (18) of the rod guide (15). The protection cap (35) is positioned over the oil seal (25) and around the piston rod (150) in a manner such that the circumferential wall (35W) of the protection cap (35) rests over the reinforcing metal insert (26) of the oil seal. The central opening (35H) of top wall (38) of the protection cap (35) maintains the radial gap (45) between the outer peripheral surface of the piston rod (150) and the inner peripheral surface of the central opening (35H) of the protection cap (35) so as to allow the insertion of the gas filling tool. The protection cap (35) is finally sealed by crimping the edge (102E) of the top end (102) of the outer tube (100) over the base wall (36) of the said protection cap (35).

[0038] During filing the gas inside the gas chamber (70) of the emulsion shock absorber (1000), the gas filling tool, such as a half locator, is sleeved over the piston rod (150) and is pushed towards the seal assembly (10). The radial gap (45), between the outer peripheral surface of the piston rod (150) and the inner peripheral surface of the central opening (35H) of the protection cap (35), allows the insertion of the tip of the gas filling tool inside the seal assembly (10). The gas filling tool is pressed towards to the oil seal (25) until it opens the first lip (29) of the oil seal (25) which consequently allows the nitrogen gas (N2) to flow along the surface of the piston rod (150) from the needle of the gas filling tool. The pressure of the nitrogen gas (N2) opens the second and third lips (30, 31) of the oil seal (25), leading to the flow of gas into the cavity (18) of the rod guide (18). Further, the nitrogen gas (N2) passes through the channels (21) of the rod guide (18) and allowing the gas to be filled inside the gas chamber (70) of the shock absorber (1000). After filling the required nitrogen gas inside the chamber (70), the gas filling tool is removed, and the lips of the oil seal (25) are closed due to the elastomeric nature of the said lips of the oil seal (25). This unique path of filling gas inside the gas chamber of the emulsion shock absorber facilitates leak-proof gas filling and allows the refilling of gas without requiring any skilled manpower and without any scratch on the surface of the piston rod.

[0039] Thus, the novelty of the present invention lies in the uniquely profiled sealing assembly (10) wherein the protection cap (35) having a top wall (38) joined with the base wall (36) with the help of a tapered wall (37) and said tapered wall (37) has a tapered angle (a) provided therein to protect the lips of the oil seal (25). The protection cap (35) has a plurality of uniquely profiled ribs (39) having a plurality of curved ramp portions (39A-39C) positioned on the lower portion (35L) of the said protection cap (35). The ribs (39) not only provides the required mechanical strength to the protection cap (35) to withstand the impact load applied by the bump stop (200) but also protects the lips of the oil seal by the virtue of the uniquely profiled ramp portions. Further, the said protection cap (35) has a central opening (35H) having an intelligently optimized diameter (Dh) which allows the passage of the gas filling tool therefrom to facilitate the filling of the nitrogen gas within the shock absorber (1000). These novel features of the protection cap (35) of the sealing assembly (10) do contribute to the technological advancement in the domain of the gas filling and sealing assembly and also impart technical advantages as discussed above. Thus, the invention qualifies the test of inventive step also. Additionally, the technical advantages derived from the invention are as under.

[0040] The sealing assembly of the present invention in accordance with the discussed embodiments provide the following technical advantages that contribute to the technical advancement of the seal assembly for emulsion shock absorber:
- The unique seal assembly for the emulsion shock absorber of the present invention provides a space for filling the gas inside the gas chamber.
- The present invention facilitates a leak-proof gas filling and repeatedly filling of gas without requiring any skilled manpower.
- The present invention avoids the damage of oil seal lips during filling the gas.
- The present invention avoids the leakage of the gas and oil from the shock absorber and also avoid the ingression of the dust particle inside the shock absorber.
- It provides a unique protection cap which provide better strength to sustain the impact load of the bump stop during full compression stroke and also provide a resting surface for the bump stop during the compression stroke.

[0041] 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 sealing assembly (10) for emulsion shock absorber (1000) of a vehicle comprising of a protection cap (35), a rod guide (15) and an oil seal (25)
wherein,
- the protection cap (35) is configured to have a disc portion (35D) and a circumferential side wall (35W); said disc portion (35D) has a stepped profile having a flat base wall (36), a tapered wall (37) and a flat top wall (38) wherein the tapered wall (37) merges with the flat base wall (36) and the flat top wall (38) to form the said disc portion (35D), and the circumferential side wall (35W) projects in a downward direction from the base wall (36) in an integral manner;
- the rod guide (15) have cylindrical multistep profile and is configured to have a main body (16), a central bore (17), a cavity (18), a seat (19), a groove (20), a plurality of channels (21) and a lower projection (22);
- the oil seal (25) formed by over-molding the elastomeric material around the metal insert (26) is configured to have a reinforcing metal insert (26), a reinforcement ring (R), a first seal lip (29), a second seal lip (30), a third seal lip (31) and a skirt lip (28);
- said oil seal (25) is sleeved over a piston rod (150) and abuts over the rod guide (15) interposing the skirt lip (28) of the oil seal (25) in the groove (20) of said rod guide (15); the middle lip (30) and the lower lip (31) are configured to get positioned inside the cavity (18) of the rod guide (15); and said protection cap (35) is positioned over the oil seal (25) and concentrically sleeved over the piston rod (150) making the circumferential wall (35W) of the protection cap (35) to rest over the reinforcing metal insert (26) of the oil seal to form the sealing assembly (10); and
- said sealing assembly (10) is positioned in a gap (G) formed between the top end (52) of an inner tube (50) and the top end (102) of an outer tube (100) so that the central opening (35H) of the protection cap (35) maintains the radial gap (45) with the outer peripheral surface of the piston rod (150) to allow the insertion of the gas filling tool.

2. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 1, wherein
- the opening (35H) on the top wall (38) of the protection cap (35) is configured to pass the piston rod (150) through it;
- the base wall (36), tapered wall (37) and the top wall (38) of the disc portion (35D) has a uniform thickness and the circumferential wall (35W) is configured to have thickness greater than the thickness of the disc portion (35D) of the protection cap (35);
- the base wall (36) of the disc portion (35D) of the protection cap (35) is configured to provide the resting surface for the crimped edge (102E) of the top end (102) of the outer tube (100);
- the tapered wall (37) is configured to make a taper angle (a) with the base wall (36) and said taper angle (a) is in conformation with the profile of the first seal lip (29) of the oil seal (25) so as to protect the said lip (29) from damage during assembly and working of the shock absorber; and
- the top wall (38) is configured to provide the resting surface for the bump stop (200) so as to achieve the required bottoming load during the extreme compression stroke of the shock absorber (1000).

3. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 2, wherein
- the taper angle (a) made by the tapered wall (37) with the base wall (36) of the protection cap (35) is in the range of 25 to 35°;
- the central opening (35H) of the protection cap (35) has a diameter (Dh), and said diameter (Dh) of the opening (35H) is greater than the diameter (Dp) of the piston rod (150) and is configured to form a radial gap (45) with the outer peripheral surface of the piston rod (150);
- the ratio of the diameter (Dp) of piston rod (150) and the diameter (Dh) of the central opening (35H) of the protection cap (35) is in the range of 1:1.20 to 1:1.25; and
- the radial gap (45) is configured to receive a gas filling tool for filling the gas inside the gas chamber (70) of the emulsion shock absorber (1000).

4. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 3, wherein
- the protection cap (35) of the sealing assembly (10) is configured to have a plurality of ribs (39) having a thickness (t) formed at its lower portion (35L) and said ribs (39) vary from three to six ribs positioned at an equiangular distance to each other;
- said ribs (39) extends from the inner peripheral surface of the circumferential wall (35W) and flush to merge with the outer peripheral edge (38E2) of the inner top surface of the top wall (38);
- said ribs (39) are configured to have a curved ramp shaped profile having a first curved ramp (39A) and a second curved ramp (39B) wherein the first curved ramp (39A) extends from the outer peripheral edge (38E2) of the inner top surface (38IT) of the top wall (38) to the mid segment (37M) of the tapered wall (37), and the second curved ramp (39B) extends from the mid segment (37M) of the tapered wall (37) to the inner peripheral surface of the circumferential wall (35W) of the protection cap (35); and
- the first ramp (39A) makes a ramp angle (ß) with respect to the horizontal axis of the top wall (38) of the protection cap (35), and the second ramp (39B) makes a ramp angle (?) with respect to the horizontal axis of the base wall (36) of the protection cap (35).

5. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 4, wherein
- the thickness (t) of the ribs (39) on the protection cap (35) is in the range of 1.5 mm to 3.0 mm and said thickness (t) of the ribs (39) is configured to maintain the position of the oil seal (25) and avoid the damage of the lip and body of the oil seal (25) from the bump stop (200) during compression stroke;
- the ramp angle (ß) made by the first ramp (39A) is in the range of 45 to 65°, and the ramp angle (?) made by the second ramp (39B) is in the range of 55 to 75°; and
- the ribs (39) of the protection cap (35) are configured to impart the required mechanical strength to withstand the impact load applied by the bump stop (200) during the extreme compression stroke of the shock absorber (1000); and the profile said ramps (39A, 39B) of the ribs (39) is configured to protect the lips (29) of the oil seal (25) during the assembly and working of the shock absorber.

6. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 3, wherein
- the protection cap (35) is configured to have a plurality of ribs (39’) varying from four to six ribs positioned at an equiangular distance to each other;
- said ribs (39’) extends from the inner peripheral surface of the circumferential wall (35W’) and flush to merge with the inner peripheral edge (38E1’) of the inner top surface of the top wall (38’);
- said ribs (39’) are configured to have a curved ramp shaped profile having a first curved ramp (39A’), a second curved ramp (39B’) and a third curved ramp (39C); and
- said first ramp (39A’) is configured to make a ramp angle (ß’) with the horizontal axis of the top wall (38’) and said second ramp (39B’) makes a ramp angle (?’) with the horizontal axis of the base wall (36’).

7. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 6, wherein
- the first curved ramp (39A’) extends from the inner peripheral edge (38E1’) of the inner top surface (38IT’) to the outer peripheral edge (38E2’) of the inner top surface (38IT’) and the ramp angle (ß’) made by said first ramp is with the horizontal axis of the top wall (38’) is in the range of 45 to 65°;
- the second curved ramp (39B’) extends from the outer peripheral edge (38E2’) of the inner top surface (38IT’) of the top wall to the outer peripheral edge of the tapered wall (37’) and the ramp angle (?’) made by said second ramp (39B’) with the horizontal axis of the base wall (36’) is in the range of 55 to 75°;
- the third curved ramp (39C) extends from the to the outer peripheral edge (37E2’) of the tapered wall (37) to the inner peripheral edge of the circumferential wall (35W’) of the protection cap (35); and
- said ribs (39’) of the protection cap (35) are configured to withstand the impact load applied by the bump stop (200) during the extreme compression stroke of the shock absorber (1000); and said ramp profiles (39A’, 39B’, 39C) of the ribs (39’) are configured to protect the lips (29) of the oil seal (25) during the assembly and working of the shock absorber.

8. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in any of the claims 5 and 7, wherein
- the first seal lip (29) of the oil seal (25) is configured to converge away from the inner edge of reinforcing metal insert (26);
- the second seal lip (30) and the third seal lip (31) of the oil seal (25) are configured to converge away from inner edge of reinforcing metal insert (26) but in a direction opposite to that of first seal lip (29);
- the third seal lip (31) of the seal (25) has a recess to house the reinforcement ring (R) and said reinforcement ring (R) is configured to impart radial load on the seal lip (31) so as to enhance the sealing effect on the piston rod (150);
- the skirt lip (28) is formed at outer periphery of the main rubber body (26) of the oil seal (25) and projects downwards towards the inner diameter of outer tube (100); and
- said oil seal (25) is sleeved over the piston rod (150) abutting over the rod guide (15) in such manner that the said skirt lip (28) of the oil seal (25) is interposed in the groove (20) of the rod guide (15), and the middle lip (30) and the lower lip (31) are positioned inside the cavity (18) of the rod guide (15).

9. The sealing assembly (10) for emulsion shock absorber (1000) as claimed in claim 8, wherein
- the rod guide (15) is configured have a larger diameter at its central bore (17) than the outer diameter of the piston rod (150) and said central bore (17) is configured to create a radial space (RS) with the outer periphery of the piston rod (150);
- said radial space (RS) is configured to receive a bush (24) to avoid the friction during reciprocation of the piston rod (150);
- said rod guide (15) is profiled to have a cavity (18) coaxially adjacent to the central bore (17) and said cavity (18) is configured to receive a lip portion (31) of the oil seal (25);
- the seat (19) of the cavity (18) is configured to provide a resting surface for the oil seal (25);
- the main body (16) of the rod guide (15) has a projection (22) and said projection (22) is configured to be interposed inside the inner tube (50) through transition fit;
- the main body (16) and the projection (22) of the rod guide (15) are integrally connected through a tapered portion (T) and said tapered portion (T) is configured to have channels (21) thoroughly passing through the tapered portion (T); and
- said channels (21) are positioned diametrically opposite to each other in the tapered profile (T) and are configured to fluidly connect the cavity (18) and the gas chamber (70) thereby forming a passage for filling the nitrogen gas in the said gas chamber (70) of the shock absorber (1000).

Dated this 29th day of Oct. 2024

(Sahastrarashmi Pund)
Head – IPR
Endurance Technologies Ltd.

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