Image Number 2 for United States Patent #4694939.
A shock absorber assembly of the so-called primary type in which the outer cylinder includes a central main body smooth walled cylindrical portion and reduced diameter threaded portions are provided at each end of the main body portion for mounting purposes. The assembly of the invention includes a stop collar which is adapted to be threaded onto the front reduced diameter threaded portion of the shock absorber and which has a length which is precisely dimensioned relative to the effective length and stroke of the shock absorber such that the object hitting the impact pad of the shock absorber will encounter the front annular edge of the stop collar just prior to bottoming of the piston of the shock absorber against the end wall of the cylinder. In front mount installations, the length of the stop collar is slightly greater than the length of the reduced diameter front portion of the cylinder plus the effective length of the shock absorber minus the prescribed thickness of the front mounting bracket and minus the stroke of the shock absorber cylinder. In rear mount installations, the length of the stop collar is slightly greater than the length of the front reduced diameter portion plus the effective length of the shock absorber minus the stroke of the shock absorber.