Abstract: A shock absorber includes an outer tube, an inner tube having a proximal end sleeved slidably into the outer tube and a distal end extending away from the outer tube, a shaft disposed inside the inner tube, a plurality of shock absorbing elastic blocks which are mounted on the outer tube for positioning resiliently the distal end away from the outer tube and which are sleeved around the shaft inside the inner tube without contacting the inner tube, each block having an inner tubular part sleeved around the shaft, and an outer tubular part wrapped around the inner tubular part. The inner and outer tubular parts are made of rubber materials having different degrees of stiffness. The inner tubular part has a stiffness higher than that of the inner tubular part to resist and limit impact pressure acting on the outer tubular part, thereby reducing deformation of the outer tubular part along radial directions and preventing the blocks from contacting the inner tube upon shock.

Abstract: A process for manufacturing a wheel of a roller skate with a hub and a wheel body fixed around the hub is disclosed. The wheel body has a soft inner portion which is mounted around the hub and a hard outer portion which is fixed around the soft inner portion. The process includes: connecting two ends of a rubber tube in order to form a molding loop; forming a radial hole in the molding loop; charging a foamable rubber material into the molding loop via the radial hole; allowing the foamable rubber material to foam and fill the molding loop in order to form the inner portion of the wheel body; mounting the molding loop around an outer periphery of the hub; and injection molding a rubber material in a mold in order to form the outer portion of the wheel body around the molding loop and the outer periphery of the hub and in order to melt the molding loop and interconnect the foamable rubber material and the outer portion.

Abstract: A grip sleeve is manufactured by sleeving a tubular nylon fabric lining on a cylindrical mandrel of appropriate length. The mandrel is then provided on a lower mold half which is formed as an elongated shell that is semi-circular in cross-section. The lower mold half has an inner surface which is formed with a pair of spaced and curved radial projections that support the mandrel. An upper mold half is provided on top of the lower mold half and matches with the lower mold half. The upper and lower mold halves cooperate with the mandrel to define an enclosed annular receiving space. One of the upper and lower mold halves is formed with an inlet to access the receiving space. A molding composition of elastomeric foam is introduced into the receiving space via the inlet so as to fill the receiving space. The molding composition solidifies to form an elastic and perspiration holding layer on the fabric lining, thereby producing the grip sleeve.