A spring frame designed for Gradua gear machines. Patent is by Mr. F. W. Barnes, of Zenith fame.
A Neat and Novel Device for Gradua Gear Machines.
THE patent files frequently reveal activities in the designing departments of motor cycle manufacturers of whicli the public know little. Sometimes the publication of a patent specification by the Patent Office is the first and last intimation of certain experiments or ideas. On the other hand, such specifications in some cases herald the advent of a new model. Whichever of these two may be the case in the present instance, a spring frame embodying the Zenith-Gradua gear and a flat twin engine by Mr. Fred W. Barnes are of more than ordinary interest.
It is fairly obvious on examination that the design is more than a diagrammatic drawing, such as forms part of the average patent specification, and this strengthens the impression that the flat twin engine is included for a purpose, and not merely to indicate the position of an engine of any type. The countershaft drive, too, is suggested. However, the subject of the patent is the spring frame.
The main part of the frame is a rigid structure. To this is connected a linked wheel frame comprising the bottom tubes and the back stays. The lower ends of the back stays carry bifurcated brackets, which straddle over the bottom tubes and support each a pair of rollers which respectively engage the upper and lower sides of the bottom tubes. These rollers are grooved to prevent lateral displacement.
Coiled tension springs are attached at one end to the brackets, and at the other end are connected adjustably to lugs or the bottom tubes.
The Motor Cycle January 23rd, 1919. Page 95.
