Frank- At first it seemed insignificant, but now I see a possibility: The problem of repetition in the vertical action involves getting the jack tip back under the butt without introducing lost motion. In this modification, the spring doesn't effect the hammer until about half-way into the hammer stroke. This would allow a faster initial acceleration of the hammer. Then, when the hammer is returned to the rest position, the spring has released, and the hammer is just a little past it's balance point, so there will be less resistance to the jack returning under the butt. The spring can be stronger where it matters in the cycle, and disconnected where it interferes with fast repetition. They might have a surprisingly simple solution to an old problem! Ed Sutton > The attached patent illustrations make it clear. > Frank Emerson
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