Detachable skateboard assembly

Abstract

The detachable skateboard assembly includes a base part configured for detachable attachment to a board and an upper part configured for detachable attachment to the base part. The upper part is coupled to the base part in such a way that they can pivot relative to each other about a first pivoting axis. The detachable skateboard assembly further includes a wheel unit configured for attachment to the upper part and an elastomeric element arranged between the base part and the upper part such that the elastomeric element is compressed by the pivoting movement between the upper part and the base part. The elastomer element exerts a force tending to make the upper part and base part to recover a neutral position corresponding to the rectilinear displacement of the skateboard.

1 . A detachable skateboard assembly comprising:
 a base part configured for detachable attachment to a board,   an upper part configured for detachable attachment to the base part, the upper part being coupled to the base part in such a way that the upper part and the base part are configured to pivot relative to each other about a first pivoting axis,   a wheel unit configured for attachment to the upper part, and   an elastomeric element arranged between the base part and the upper part such that the elastomeric element is compressed by the pivoting movement between the upper part and the base part, the elastomeric element exerting a force tending to make them recover a neutral position corresponding to the rectilinear displacement of the skateboard.   
     
     
         2 . The detachable skateboard assembly according to  claim 1 , wherein the elastomeric element comprises a material which comprises at least one elastomer, wherein the elastomer is selected from the group consisting of natural rubber, butyl rubber, copolymers of isobutylene and para-alkylstyrene, polyisoprene, polybutadiene, ethylene-propylene rubber, ethylene-propylene-diene monomer rubber, silicone elastomers, polyurethane, nitriles, styrenic block copolymer rubber, butadiene-acrylonitrile copolymers and alkyl acrylate rubber; wherein the elastomer is selected from the group consisting of natural rubber, butyl rubber, polyisoprene, polybutadiene, ethylene-propylene rubber, ethylene-propylene-diene monomer rubber, polyurethane, styrenic block copolymer rubber and alkyl acrylate rubber. 
     
     
         3 . The detachable skateboard assembly according to  claim 2 , wherein the at least one elastomer is polyurethane with a Shore hardness in the range of 60 to 100. 
     
     
         4 . The detachable skateboard assembly according to  claim 2 , wherein the at least one elastomer is polyurethane, obtained by reacting a polyisocyanate prepolymer with a curative composition, wherein the curative composition comprises:
 a polymerization catalyst;   a polyol selected from polyether polyols and polyester polyols; and   a chain extender.   
     
     
         5 . The detachable skateboard assembly according to  claim 1 , wherein the upper part or the base part comprises a cam element configured to push upon the elastomeric element during the pivoting movement between the upper part and the base part causing an elastic compression of the elastomeric element. 
     
     
         6 . The detachable skateboard assembly according to claim wherein the base part or the upper part comprises a housing configured to accommodate the elastomeric element leaving a clearance space, the cam element being configured to be fitted in the clearance space. 
     
     
         7 . The detachable skateboard assembly according to claim wherein the elastomeric element comprises a plurality of pieces and wherein at least two pieces of the plurality of pieces comprise a first edge and an opposite second edge, the at least two pieces being placed in the housing such that the second edges of both pieces keeps facing each other leaving a free space defining the clearance space. 
     
     
         8 . The detachable skateboard assembly according to previous  claim 1 , wherein the base part, the elastomeric element or both comprise retention means to block the movement of the elastomeric element during the relative pivoting movement between the upper part and the base part. 
     
     
         9 . The detachable skateboard assembly according to  claim 8 , wherein the first edge of the two pieces of the elastomeric element is placed in the housing facing the retention means such that the pivoting movement between the upper part and the base part causes the pushing of the cam element against one of the second edges and the compression of the elastomeric piece pushing one of the first edges upon the retention means. 
     
     
         10 . The detachable skateboard assembly according to  claim 1 , comprising a bolt passing the base part and the upper part such that the upper part is configured to pivot relative to the base part around said bolt and wherein the bolt comprises a bolt head and a threaded edge, the bolt head being configured to push upon the base part and the threaded edge protruding partially outside the upper part such that a locking nut engages the threaded edge of the bolt blocking together the upper part and the base part in the direction of the first pivoting axis. 
     
     
         11 . The detachable skateboard assembly according to  claim 10 , comprising a lower axial bearing located between the base part and the upper part, an upper axial bearing located between the upper part and the locking nut, and a bronze bushing between the lower axial bearing and the upper axial bearing, such that the bolt extends through the base part, the lower axial bearing, the bronze bushing, the upper part, the upper axial bearing and the locking nut. 
     
     
         12 . The detachable skateboard assembly according to  claim 1 , wherein the upper part comprises a pedestal for the coupling to the base part and an elongated arm for the attachment of a wheel unit, the wheel unit comprising a hanger with two axle rods for the wheels and a pivot pin configured to engage a pivot cup housed in a blind hole of the elongated arm, the hanger further comprising a platform with an eyelet suitable for the attachment to the upper part by means of a kingpin and a couple of bushings, the kingpin passing through the eyelet, the bushings and a counter hole of the elongated arm of the upper part. 
     
     
         13 . The detachable skateboard assembly according to  claim 1 , wherein the upper part comprises a pedestal for the coupling to the base part and a substantially planar support base where an intermediate part of a wheel unit is configured to be attached and wherein the wheel unit further comprises a hanger with two axle rods for the wheels and a pivot pin configured to engage a pivot cup housed in a blind hole of the intermediate part ( 61 ), the hanger further comprising a platform with an eyelet suitable for the attachment to intermediate part by means of a kingpin and a couple of bushings, the kingpin passing through the eyelet, the bushings and a counter hole of the of the intermediate part. 
     
     
         14 . The detachable skateboard assembly according to  claim 1 , wherein the upper part comprises a pedestal for the coupling to the base part and a substantially vertical arm wherein and an axle comprising two axle rods for the wheels is attached. 
     
     
         15 . The skateboard comprising a detachable assembly according to  claim 1 .