Patent Publication Number: US-2020300362-A1

Title: Dirt scrapper assembly

Description:
FIELD OF INVENTION 
     The present disclosure relates to a field of a seal assembly. More specifically, the present disclosure relates to a seal assembly in an automotive industry. 
     BACKGROUND 
     As known, motorcycles or bikes are equipped with a suspension mechanism to absorb shocks or vibrations as the motorcycle travels on uneven surfaces and to isolate rest of the motorcycle from the shocks. The suspension mechanism may usually include a pair of fork tubes provided at front of the motorcycle. The fork tubes comprise springs and compartments filled with fork oil to absorb the shocks. Typically, the front of the motorcycle is provided with the suspension mechanism in a telescopic fork form. 
     It is well known that the telescopic fork is widely used as it is simple in design and is relatively easy to manufacture and assemble. The telescopic fork comprises fork tubes coupled to an outer sleeve coupled extendedly to the fork tube. The telescopic fork uses the fork tubes comprising suspension components such as the springs and dampers internally. The fork tubes are suspended on the springs and movement of the fork tubes are controlled by damping through adjustable valving to control movement by controlling the flow of the fork oil. As such, it is important to contain the fork oil inside the fork tubes. In order to contain the fork oil, the fork tubes are sealed. The seal assembly generally comprises a plurality of annular rings fit around the fork tube. 
     It is necessary that the fork tubes and its assembly should be protected from environmental influences. For example, it is necessary to protect parts and components from dust, dirt particles and droplets. As such, the fork tube and the seal is provided with a dirt scrapper to protect them from dirt and/or droplets. 
     There have been several designs proposed in the existing art disclosing dirt scrappers. For example, a Japanese utility model to Kokai having publication No. 6-28429 discloses a dust seal comprising a primary dust seal and an axillary dust sealing lip. The auxiliary dust seal functions to scrap the dust outside. In another Japanese utility model, having an application number JP2016098869A, a dust seal provided with a lip membrane is disclosed. Further, a PCT application, numbered WO2016080189A1 discloses a dust seal body and a lip membrane. 
     Further, United States granted application U.S. Pat. No. 5,649,709 discloses elastomeric materials being used for the purpose of sealing the dirt scrapper. The dirt scrapper as disclosed in U.S. Pat. No. 5,649,709 comprises an annular elastomeric primary sealing member for sealing oil side of a shaft, and an annular elastomeric dust sealing member for sealing air side of the shaft was being disclosed. 
     Furthermore, an Indian Patent application, numbered IN201621030674 discloses an integrated dust seal and sleeve guide with pads formed by integrating dust seal and oil seal. 
     Referring to  FIG. 1 , an example of existing design of a dirt scrapper assembly  100  provided on a fork tube  115  is shown. As can be seen from  FIG. 1 , a dirt scrapper assembly  100  comprises a fork outer tube  110  mechanically coupled to an outer sleeve  115 . Specifically, the inner diameter of the outer sleeve  115  is in cylindrical shape with outer diameter of the fork outer tube  110 . The fork outer tube  110  further comprises a seal assembly  120  to protect inside of the fork outer tube  115  from dirt and/or droplets. In operation, the fork outer tube  110  is guided in axial direction with respect to the outer sleeve  115 . When the fork outer tube  110  is guided in axial direction with respect to the outer sleeve  115 , the fork outer tube  110  or the seal assembly  120  comes in contact with the outer sleeve  115 . This results in riding discomfort. Further, the outer surface of the fork outer tube  110  wears out over time. 
     Therefore, there is a need to provide a seal assembly for the fork outer tube that does not come in contact with the outer sleeve during operation and protect inside of the fork outer tube during operation. 
     SUMMARY OF THE INVENTION 
     The above-mentioned problems are addressed by providing a dirt scrapper assembly for sealing a tube which does not contact with outer sleeve and takes up forces during operation. 
     This summary is provided to introduce concepts related to a dirt scrapper assembly and the concepts are further described below in the detailed description. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter. 
     In one aspect of the present disclosure, a dirt scrapper assembly for sealing a tube is disclosed. The dirt scrapper assembly comprises an annular stiffening structure adapted to connect with the tube. The annular stiffening structure comprises a plurality of first axial sections equally spaced and extended along axial direction of the tube on an outer side of the tube. The annular stiffening structure further comprises a second axial section extended along axial direction of the tube on inner side of the tube. The plurality of first axial sections and the second axial section are connected by a connection section of the stiffening structure such that bottom surface of the connection section is bought into contact with an end surface of the tube. The connection section comprises a cut section at the bottom surface extended over the length of each of the plurality of first axial sections to provide flex to the plurality of first axial sections. Each of the first axial sections comprises a snap lock hook at inner surface to connect the first axial sections with the tube via grooves provided on outer surface of the tube. 
     In another aspect of the present disclosure, curvature of corresponding radii is provided on the outer surface of the first axial sections such that an outer sleeve has minimum contact with the first axial sections when the outer sleeve is guided in axial direction with respect to the tube or fork pipe. In other words, the outer sleeve may come in contact with the first axial sections if there is an axial misalignment in the outer sleeve. In such a case, the first axial sections may avoid the contact with the outer sleeve thereby avoiding rubbing or wear on the tube or fork pipe. 
     In another aspect of the present disclosure, a dirt scrapper assembly for sealing a tube is disclosed. The dirt scrapper assembly comprises an annular stiffening structure coupled with an elastomeric structure adapted to connect with the tube. The elastomeric structure may have a contact surface connected to the tube to form a sealing arrangement between the inner surface of the tube and a second axial section and rests against the inside of the tube. The elastomeric structure enables to create an improved seal of the sealing arrangement with respect to the inside of the tube. The seal helps to prevent penetration of liquid and/or solid particles and/or liquid/gaseous medium from leaking from interior of the tube. 
     In another aspect of the present disclosure, a dirt scrapper assembly for sealing a tube is disclosed. The dirt scrapper assembly comprises an annular stiffening structure adapted to connect with the tube. The annular stiffening structure comprises a plurality of first axial sections equally spaced and extended along axial direction of the tube on an outer side of the tube. The annular stiffening structure further comprises a second axial section extended along axial direction of the tube on inner side of the tube. The plurality of first axial sections and the second axial section are connected by a connection section of the stiffening structure such that bottom surface of the connection section is bought into contact with an end surface of the tube. The connection section comprises a plurality of slots equally placed on the connection section. The plurality of slots is provided to allow the plurality of first axial sections to flex and to prevent from breaking during extreme pressure and during assembly of the dirt scrapper. 
     In yet another aspect of the present disclosure, a dirt scrapper assembly for sealing a tube is disclosed. The dirt scrapper assembly comprises an annular stiffening structure adapted to connect with the tube. The annular stiffening structure comprises a plurality of first axial sections connected mechanically to a second axial section by a connection section. The connection section comprises a relief section at an end of each of a plurality of first axial sections. The relief section is provided to improve mold construction of the plurality of first axial sections. 
     The foregoing portions has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter, which form the subject of the disclosure. It should be appreciated that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The detailed description is described with reference to the accompanying figures. In the figures, a reference number is used to identify a part of a dirt scrapper assembly for sealing a tube. The same numbers are used throughout the drawings to refer like/similar features and components. 
         FIG. 1  shows a dirt scrapper assembly is shown, as known in the art; 
         FIG. 2A  shows a cross-sectional view of a dirt scrapper assembly, in accordance with one embodiment of the present disclosure; 
         FIG. 2B  shows a cross-sectional view of an annular stiffening structure coupled to an elastomeric structure, in accordance with one embodiment of the present disclosure; 
         FIG. 3A  shows a cross-sectional front view of an annular stiffening structure, in accordance with one embodiment of the present disclosure; 
         FIG. 3B  shows a top view of the annular stiffening structure of  FIG. 3A ; 
         FIG. 3C  shows a perspective view of the annular stiffening structure of  FIG. 3A ; 
         FIG. 4  shows a top view of an annular stiffening structure comprising a plurality of slots provided on a connection section, in accordance with another embodiment of the present disclosure; 
         FIG. 5  shows a cross-sectional view of a dirt scrapper assembly, in accordance with another embodiment of the present disclosure; 
         FIG. 6  shows a cross-sectional view of a dirt scrapper assembly, in accordance with yet another embodiment of the present disclosure; 
         FIG. 7  shows a perspective view of an annular stiffening structure, in accordance with another embodiment of the present disclosure; 
         FIG. 8  shows a cross-sectional front view of an annular stiffening structure, in accordance with another embodiment of the present disclosure; and 
         FIG. 9  shows a cross-sectional view of the dirt scrapper assembly, in accordance with another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description is intended to provide example implementations to one of ordinary skill in the art, and is not intended to limit the invention to the explicit disclosure, as one or ordinary skill in the art will understand that variations can be substituted that are within the scope of the invention as described. 
     In the present description summarizing reference numerals will be used for objects, structures, and other components, if the component in question are described per se or more relevant components within an embodiment or within several embodiments. Passages of the specification which refer to a component, therefore also on other components in other embodiments, transferable, unless this is explicitly excluded or if it is evident from the context. When individual components referred to individual numerals are used that are based on the corresponding summary numerals. In the following description of embodiments, therefore, like reference numerals designate identical or comparable components. 
     Components that occur more than once in one embodiment, or in different embodiments can occur to respect some of its technical parameters executed or implemented identically and/or differently. It is for example possible that more entities can be identical, however, with respect to another parameter implemented in different ways in an embodiment with respect to a parameter. 
     Although the following embodiments of a dirt scrapper assembly in particular in connection with motorcycles and scooters are described, embodiments are, however, far from being limited to these applications. Thus, a dirt scrapper assembly according to an embodiment is basically for sealing of each cylindrical member with respect to a suitable tube. Depending on the specific embodiment, where appropriate, with a degree of sealing action of a moving direction of the cylindrical member to the depending pipe. As hereinafter be considered substantially movements of the cylindrical member relative to the tube is considered to take place along the axial direction of the cylindrical member and the tube. 
     For the motorcycles and scooters, fork seal assembly is used to prevent the dirt and droplets from entering inside of the fork tube. As such, the present disclosure discloses a dirt scrapper assembly for sealing a tube or fork pipe. The dirt scrapper assembly comprises an annular stiffening structure adapted to connect with the tube. The annular stiffening structure comprises a plurality of first axial sections equally spaced and extended along axial direction of the tube on an outer side of the tube. Further, curvature of corresponding radii is provided on the outer surface of the first axial sections such that an outer sleeve does not come in contact with the first axial sections when the outer sleeve is guided in axial direction with respect to the tube or fork pipe. 
     The annular stiffening structure further comprises a second axial section extended along axial direction of the tube on inner side of the tube. The plurality of first axial sections and the second axial section are connected by a connection section of the stiffening structure such that bottom surface of the connection section is bought into contact with an end surface of the tube. The connection section comprises a cut section at the bottom surface extended over the length of each of the plurality of first axial sections to provide flex to the plurality of first axial sections. Each of the first axial sections comprise a snap lock hook at inner surface to connect the first axial sections with the tube via grooves provided on outer surface of the tube. 
     Various features and embodiments of the dirt scrapper assembly for sealing a tube are explained in conjunction with the description of  FIGS. 2A-9 . 
       FIG. 2A and 2B  shows a cross-sectional view of a dirt scrapper assembly  200  for a sealing a tube  210 , in accordance with one embodiment of the present disclosure. The tube  210  indicates the fork which comprises lubricating oil and damping assembly (not shown). The dirt scrapper assembly  200  comprises an annular stiffening structure  205  adapted to connect with the tube  210 . Particularly, the tube  210  comprises a recess or groove  245  to connect with the annular stiffening structure  205 . Other features of the annular stiffening structure  205  is explained in later part of the description. The dirt scrapper assembly  200  further comprises an outer sleeve  212  provided on outer surface of the annular stiffening structure  205 . As presented above, the outer sleeve  212  and the tube  210  are guided in axial direction during operation of the front fork assembly. 
     The annular stiffening structure  205  comprises a plurality of first axial sections  215  extended along axial direction of the tube  210 . The plurality of first axial sections  215  are on an outer side of the tube  210 . The plurality of first axial sections  215  are equally spaced indicating that a section of outer circular ring of the annular stiffening structure  205  is cut at equal lengths to form a plurality of first axial sections  215 . The plurality of first axial sections  215  are equally spaced to provide flexibility to the part and to prevent from breaking when the annular stiffening structure  205  goes under extreme pressure. Further, each of the plurality of first axial sections  215  may have a curvature provided on outer surface in order to minimize contact with the outer sleeve  212  during the operation. Further, the annular stiffening structure  205  comprises a second axial section  220  along axial direction of the tube  210 . The second axial section  220  is provided on an inner side of the tube  210 . In other words, the second axial section  220  is an inner circular ring of the annular stiffening structure  205 , as shown in  FIG. 2B . The plurality of first axial sections  215  are provided in a radial direction of the second axial section  220  for connection to the outside of the tube on opposite sides. In other words, the plurality of first axial sections  215  and the second axial section  220  face each other and opposed to each other in the axial direction. It is preferable to have length of each of the plurality of first axial sections  215  greater than that of the second axial section  220 . However, length of the first axial sections  215  and the second axial section  220  should not be taken to be limiting the disclosure. 
     The annular stiffening structure  205  is tailored to a diameter of the cylindrical structure of the tube  210  such that the plurality of first axial sections  215  are formed in the area having the outer diameter of the tube  210 . Further, the second axial section  220  is tailored to have the inner diameter of the tube  210 . The annular stiffening structure  205  further comprises a connection section  225  which connects the plurality of first axial sections  215  and the second axial section  220 . The plurality of first axial sections  215 , the second axial section  220  and the connection section  225  provide a mechanically structure which is essentially U-shared structure encompassing the tube  210 . It is understood that the connection section  225  may come in contact with the tube  210  directly or indirectly at an end section  230  of the tube  210 . When the end section  230  of the tube  210  is brought into contact with the connection section  225  either directly or indirectly, the end section  230  of the tube  210  and the connection section  225  comes substantially perpendicular to the axial direction. In other word, the end section  230  of the tube  210  limits the tube  210  along the axial direction. 
     The annular stiffening structure  205  is made of one of an unfilled plastic, a Glass filled plastic, an unfilled Thermoplastic Elastomer (TPE), a Glass filled Thermoplastic Elastomer (TPE), and a polyurethane. 
     The connection section  225  further comprises a cut section  235  provided at bottom surface extended over the length of each of the plurality of first axial sections  215 . The cut section  235  is provided such that the plurality of first axial sections  215  flexes when the annular stiffening structure  205  comes under stress during operation. 
     In addition, each of the plurality of first axial sections  215  comprises a snap lock hook  240  extending from inner surface. Particularly, the snap lock hook  240  is adapted to connect with the tube  210  on an outer surface of the tube  210  via the groove  245  provided on outer of the tube  210 . The snap lock hook  240  helps in positive locking of the annular stiffening structure  205  to the outer surface of the tube  210  and prevents popping due to extreme pressure exerted by the outer sleeve  212 . In other words, the snap lock hook  240  provides positive connection with the groove  245  provided on outer of the tube  210 . The positive connection indicates a mechanical interlocking of two parts i.e., interlocking of the snap lock hook  240  and groove  245 . The annular stiffening structure  205  comprising the plurality of first axial sections  215 , the second axial section  220  and the connection section  225  is connected over the tube  210  such that the connection section  225  with the help of snap lock hook  240  acts as a stopper and forms a locking-connection only in one direction. 
     In one embodiment, the dirt scrapper assembly  200  comprises an elastomeric structure  280  extended between the annular stiffening structure  205  and the end section  230  of the tube  210 . In one example, the elastomeric structure  280  is made up of rubber. The elastomeric structure  280  is connected to the annular stiffening structure  205  by means of a material connection such as by bonding or by vulcanizing. In other embodiment, the elastomeric structure  280  is connected to the annular stiffening structure  205  by welding, vulcanization techniques, post vulcanization, and other connecting mechanisms known in the art. 
     The annular stiffening structure  205  and the elastomeric structure  280  are bonded together to form a seal arrangement. The seal arrangement helps to avoid dirt and/or droplets from entering inside of the tube  210 . In one implementation, the annular stiffening structure  205  is made up of for example, plastic may be formed integrally. The elastomeric structure  280  may additionally or alternatively not be releasably connected to the annular stiffening structure  205 . The seal arrangement of the annular stiffening structure  205  and the elastomeric structure  280  may be formed using injection molding or compression molding. The elastomeric structure  280  may be bonded or vulcanized with the annular stiffening structure  205 . It should be obvious to a person skilled in the art to connect the annular stiffening structure  205  with the elastomeric structure  280  using other material connection techniques. 
     The elastomeric structure  280  may comprise a contact surface  285  connected to the tube  210  to form a sealing arrangement between the inner surface of the tube  210  and second axial section  220  and rests against the inside of the tube  210 . In other words, the contact surface  285  is provided between the inner side of the tube  210  (and inner surface of the second axial section  220  of the annular stiffening structure  205 ). The contact surface  285  acts as a static sealing and the second axial section  220  exerts pressure for the static sealing with the contact surface  285 . The elastomeric structure  280  enables to create an improved seal of the sealing arrangement with respect to the inner side of the tube  210 . The seal helps to prevent penetration of liquid and/or solid particles. 
     Now, referring to  FIG. 3A , a cross-sectional front view of an annular stiffening structure  300  is shown, in accordance with one embodiment of the present disclosure. As can be seen, the annular stiffening structure  300  comprises a plurality of first axial sections  315 . The plurality of first axial sections  315  are equally spaced indicating that a section of outer circular ring of the annular stiffening structure  300  is cut at equal lengths to form a plurality of first axial sections  315 . Further, the annular stiffening structure  300  comprises a second axial section  320  along axial direction of the tube plurality of first axial sections  315 . Further, each of the plurality of first axial sections  315  comprises a snap lock hook  325 . The snap lock hook  325  is provided on inner surface of the first axial sections  315 . Furthermore, the second axial section  320  comprises a plurality of ribs  340  equally spaced on outer surface of the second axial section  320 . In other words, the plurality of ribs  340  are provided on the surface of the second axial section  320  that comes in contact with the contact section ( 285  in  FIG. 2 ) of the elastomeric structure ( 280  in  FIG. 2 ) i.e., away from the plurality of first axial sections  315 . The plurality of ribs  340  are equally spaced to maintain circular form of the second axial section  320 . 
     Referring to  FIG. 3B , a top view of the annular stiffening structure  300  is shown, in accordance with one embodiment of the present disclosure. As can be seen, the plurality of first axial sections  315  are connected mechanically to the second axial section  320  by a connection section  330 . Further, the ribs  340  provided on the second axial section  320  is shown. 
     Referring to  FIG. 3C , a perspective view of the annular stiffening structure  300  is shown, in accordance with one embodiment of the present disclosure. As can be seen, the plurality of first axial sections  315  are connected mechanically to a second axial section  320 . Each of the plurality of first axial sections  315  comprises a snap lock hook  325 . Further, the second axial section  320  comprises a plurality of the ribs  340  on outer surface, as presented above. 
     Now, referring to  FIG. 4 , a top view of an annular stiffening structure  400  comprising a plurality of slots  450  provided on a connection section  430  is shown, in accordance with an alternate embodiment of the present disclosure. The annular stiffening structure  400  comprises a plurality of first axial sections  415  connected mechanically to a second axial section  420  by the connection section  430 . Further, the second axial section  420  comprises a plurality of the ribs  440  on outer surface. The connection section  430  comprises a plurality of slots  450  equally placed on the connection section  430 . Specifically, the plurality of slots  450  are provided where the plurality of first axial sections  415  are present. The plurality of slots  450  are provided to allow the plurality of first axial sections  415  to flex and to prevent from breaking during extreme pressure. 
     In an alternate embodiment, a protruded section may be provided for the annular stiffening structure, as shown in  FIG. 5 . Referring to  FIG. 5 , a cross-sectional view of a dirt scrapper assembly  500  comprising an annular stiffening structure  505  is shown. The annular stiffening structure  505  comprises a plurality of first axial sections  515 . The annular stiffening structure  505  comprises a second axial section  520  mechanically coupled to the plurality of first axial sections  515  via a connection section  525 . Each of the plurality of first axial sections  515  may further comprise a rib  540 . The annular stiffening structure  505  is further connected to an elastomeric structure  560  by means of a material connection. For example, the annular stiffening structure  505  is connected to the elastomeric structure  560  by bonding or by vulcanizing. The elastomeric structure  560  comprises a contact surface  565  connected to the second axial section  520 . 
     In the present embodiment, the connection section  525  comprises a cut section  535  provided at bottom surface extended over the length of each of the plurality of first axial sections  515 . Further, the connection section  525  comprises a protruded section  545  provided on top surface extended over the length of each of the plurality of first axial sections  515 . The protruded section  545  is provided as a beaded rib structure along the top surface of the connection section  525 . The protruded section  545  is provided to close any split gap that may have formed between the annular stiffening structure  505  and a tube (similar to the tube  210 ). The cut section  535  and the protruded section  545  allows the plurality of first axial sections  515  to flex when the annular stiffening structure  505  comes under stress during operation and during assembly of the dirt scrapper  500 . 
     In yet another alternate embodiment, a protruded section may be provided for the annular stiffening structure, as shown in  FIG. 6 . Further, a plurality of curvatures may be provided on the first axial sections, as shown in  FIG. 6 . Referring to  FIG. 6 , a cross-sectional view of a dirt scrapper assembly  600  comprising an annular stiffening structure  605  is shown. The annular stiffening structure  605  comprises a plurality of first axial sections  615 . The annular stiffening structure  605  comprises a second axial section  620  mechanically coupled to the plurality of first axial sections  615  via a connection section  625 . Each of the plurality of first axial sections  615  may further comprise a rib  640 . The annular stiffening structure  605  is further connected to an elastomeric structure  660  by means of a material connection. For example, the annular stiffening structure  605  is connected to the elastomeric structure  660  by bonding or by vulcanizing. The elastomeric structure  660  comprises a contact surface  665  connected to the second axial section  620 . 
     As can be seen, each of the plurality of first axial sections  615  is provided with a plurality of curvatures  630  on outer surface of the plurality of first axial sections  615 . It should be understood that one or more curvatures  630  may be provided depending upon on the material chosen for the annular stiffening structure  605 . Each of the curvatures  630  may have equal radii or varying radii depending upon the material chosen for the plurality of first axial sections  615  or the annular stiffening structure  605 . 
     In the present embodiment, the connection section  625  may comprise a cut section  635  provided at bottom surface extended over the length of each of the plurality of first axial sections  615 . Further, the connection section  625  comprises a protruded section  645  provided on top surface extended over the length of each of the plurality of first axial sections  615 . 
     The plurality of curvatures  630  provided on outer surface of the plurality of first axial sections  615 , the cut section  635  and the protruded section  645  allow the plurality of first axial sections  615  to flex when the annular stiffening structure  605  comes under stress during operation. As the plurality of first axial sections  615  flexes under stress, damage to the plurality of first axial sections  615  is minimized during operation. 
     In an alternate embodiment, an annular stiffening structure  700  may comprise a first axial section  715 , as shown in  FIG. 7 . In the present embodiment, the first axial section  715  is provided as a single circular section as opposed to equally spaced multiple first axial sections (plurality of first axial sections  215  in  FIG. 2A ). The annular stiffening structure  700  comprises a second axial section  720  mechanically coupled to the first axial section  715  via a connection section (not shown and similar to the connection section  225 ). The first axial section  715  comprises a plurality of snap lock hooks  725  provided on inner surface of the first axial section  715 . As can be seen, the second axial section  720  comprises a plurality of ribs  730  equally spaced on outer surface of the second axial section  720 . In other words, the plurality of ribs  730  are provided on the surface of the second axial section  720  that comes in contact with the contact section ( 285  in  FIG. 2 ) of the elastomeric structure ( 280  in  FIG. 2 ) i.e., away from the first axial section  715 . The plurality of ribs  730  are equally spaced to maintain circular form of the second axial section  720 . 
     It should be obvious to a person skilled in the art that the cut section (cut section  635  shown in  FIG. 6 ), and a protruded section (protruded section  645  shown in  FIG. 6 ) may be provided in the annular stiffening structure  700 , shown in  FIG. 7 . Further, the annular stiffening structure  700  comprising the first axial section  715  as a single circular section may have a plurality of curvatures (similar to plurality of curvatures  730 ). 
     The plurality of curvatures provided on outer surface of the first axial section  715 , the cut section and the protruded section allow the first axial section  715  to flex when the annular stiffening structure  700  comes under stress during operation. As the first axial section  615  flexes under stress, damage to the first axial sections  615  is minimized during operation. 
       FIG. 8  is a cross-sectional front view of an annular stiffening structure  800 , in accordance with an alternate embodiment of the present disclosure. The annular stiffening structure  800  comprises a plurality of first axial sections  810  connected mechanically to a second axial section  820  by a connection section  830 . The connection section  830  comprises a relief section  840  at an end of each of a plurality of first axial sections  810 . The relief section  840  is provided to improve mold construction of the plurality of first axial sections  810 . 
     Operational features of the dirt scrapper assembly are explained with the help of  FIG. 9 . Referring to  FIG. 9 , a cross-sectional view of a dirt scrapper assembly  900  is shown. As can be seen, the dirt scrapper assembly  900  comprises an outer sleeve  910  guided in axial direction with respect to a tube or fork pipe  915 . Further, the dirt scrapper assembly  900  comprises an annular stiffening structure  920  (also, the annular stiffening structure  205  in  FIG. 2A  and  FIG. 2B ). The annular stiffening structure  920  comprises a plurality of first axial sections  925  provided on an outer side of the tube  915 . The annular stiffening structure  920  is mechanically coupled with an elastomeric structure  930  (sealing structure) in order to seal or lock the tube  915 . Specifically, the annular stiffening structure  920  is sealed to the elastomeric structure  930  by applying pressure on the annular stiffening structure  920  (second axial section  220 ). As known, extreme pressure is applied on the sealing structure when the outer sleeve  910  is guided in axial direction with respect to the tube or fork pipe  915 . In order to prevent the seal assembly of the annular stiffening structure  920  and the elastomeric structure  930  with the tube or fork pipe  915 , snap lock hooks  940  are provided on the inner surface of the plurality of first axial sections  925 . The snap lock hooks  940  gets locked with grooves  945  provided on the outer surface of the tube  915 . As the snap lock hooks  940  gets locked with grooves  945 , the seal assembly (annular stiffening structure  620  and elastomeric structure  630 ) stays intact during the movement of the outer sleeve  910  in upward motion. In other words, the snap lock hooks  940  prevents seal disassembly during the movement of the outer sleeve  910  in upward motion. 
     Further, the plurality of first axial sections  925  flexes when extreme pressure is exerted by the outer sleeve  910  due to a cut section  950  provided at bottom of a connection section  655 . As the first axial sections  925  flex under extreme pressure, breaking of the first axial sections  925  is avoided. 
     Furthermore, curvature of corresponding radii is provided on the outer surface of the first axial sections  925  such that the outer sleeve  910  coming in contact with the first axial sections  925  is minimized when the outer sleeve  910  is guided in axial direction with respect to the tube or fork pipe  915 . As there is minimum contact between the outer sleeve  910  and the first axial sections  925 , wear on the surface of the first axial sections  925  or on the tube  915  is reduced. 
     In other words, the curvature on the outer surface of the first axial sections  925  is provided in a such a way that outer sleeve  910  make contact with the first axial sections  925  far away from the cut section  950  (pivot point) thereby increasing flexibility to the first axial sections  925 . 
     In addition, mechanical stresses produced during the operation may be distributed to the plurality of the first axial sections  925 . After undergoing the mechanical stresses, the first axial sections  925  may flex and sustain the mechanical stresses. Further, due to the snap lock hooks  940 , the annular stiffening structure  920  is connected to the grooves  945  on outer surface of the tube  915  even when undergoing the mechanical stresses thereby not snapping the connection with the tube  915 . In other words, the annular stiffening structure  925  provides the positive connection to the tube  915  on its outer side only in one direction. 
     It should be understood that the curvature of corresponding radii may be provided on the outer surface of the first axial sections depending on the size and shape of the outer sleeve such that the outer sleeve contact with the first axial sections is minimized when the outer sleeve is guided in axial direction with respect to the tube or fork pipe. 
     The length of the first axial sections and the second axial section may be chosen depending upon the diameter of the annular stiffening structure or material of the annular stiffening structure. 
     The dirt scrapper assembly may be used in self-locking motorcycle fork seal for smaller motorcycles and scooters. However, it can also be used as shock absorbers or other components of other motor vehicles and non-motorized vehicles. 
     Advantages: 
     The dirt scrapper assembly facilitates in sealing the tube effectively with the help of the elastomeric structure. 
     Further, the positive connection established between the snap lock hook and grooves allow the annular stiffening structure to withstand mechanical forces exerted during operation of the outer sleeve and the tube. 
     The annular stiffening structure have minimum contact with the outer sleeve due to the curvature of corresponding radii provided on outer surface of the first axial portion. Therefore, the annular stiffening structure does not wear out easily and provides comfort ride to users of the motorcycles or scooters. 
     The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense. 
     REFERENCE NUMERAL LIST 
     
         
           100  Dirt Scrapper Assembly (Prior Art) 
           110  Fork Outer Tube (Prior Art) 
           115  Outer Sleeve (Prior Art) 
           120  Seal Assembly (Prior Art) 
           200  Dirt Scrapper Assembly 
           205  Annular Stiffening Structure 
           210  Tube 
           212  Outer Sleeve 
           215  First Axial Sections 
           220  Second Axial Section 
           225  Connection Section 
           230  End Section 
           235  Cut Section 
           240  Snap Lock Hook 
           245  Groove 
           280  Elastomeric Structure 
           285  Contact Surface 
           300  Annular Stiffening Structure 
           315  First Axial Sections 
           320  Second Axial Section 
           325  Snap Lock Hook 
           330  Connection Section 
           340  Ribs 
           400  Annular Stiffening Structure 
           415  First Axial Sections 
           420  Second Axial Section 
           430  Connection Section 
           440  Ribs 
           450  Slots 
           500  Dirt Scrapper Assembly 
           505  Annular Stiffening Structure 
           515  First Axial Sections 
           520  Second Axial Section 
           525  Connection Section 
           535  Cut Section 
           540  Snap Lock Hooks 
           545  Protruded Section 
           560  Elastomeric Structure 
           565  Contact Surface 
           600  Dirt Scrapper Assembly 
           605  Annular Stiffening Structure 
           615  First Axial Sections 
           620  Second Axial Section 
           625  Connection Section 
           630  Curvatures 
           635  Cut Section 
           640  Rib 
           645  Protruded Section 
           660  Elastomeric Structure 
           665  Contact Surface 
           700  Annular Stiffening Structure 
           715  First Axial Section 
           720  Second Axial Section 
           725  Snap lock Hooks 
           730  Ribs 
           800  Annular Stiffening Structure 
           810  First Axial Sections 
           820  Second Axial Section 
           830  Connection Section 
           840  Relief Section 
           900  Dirt Scrapper Assembly 
           910  Outer Sleeve 
           915  Tube 
           920  Annular Stiffening Structure 
           925  First Axial Sections 
           930  Elastomeric Structure 
           940  Snap Lock Hook 
           945  Groove 
           950  Cut Section 
           955  Connection Section