The Self-Clearing Rake: A Stripper Bar and a Rubber Band

"This invention relates to iron-tooth hand-rakes, such as are commonly used in cleaning leaves and other debris from lawns, door-yards, &c. It is well known that these rakes are continually becoming clogged by the refuse matter which they collect". "Whenever the teeth become clogged, the operator has only to raise the rake from the ground, when the bar B is forced downward on the teeth, as above stated, and all obstructions are forced out, this operation involving no extra labor, as the rake is naturally lifted after every stroke." "The spring G may be adjusted by moving along the handle, so as to vary its pressure upon the lever; and, being made of rubber, it is durable and inexpensive, and can be replaced at any time without difficulty."

Take a garden rake with straight iron teeth. Drill a strip of steel sheet or hardwood with holes at the same spacing as the teeth, a little larger, and thread it onto the teeth. Screw a short lever to the middle of the strip, running back under the handle. Give it a pivot on a small block screwed under the handle. Loop a thick rubber band round the handle and the lever's end. Rake leaves. Press down: the bar should slide up to the rake head. Lift: it should slide down and push the leaves off. Move the band along the handle until it clears every stroke without dragging. Hook the force meter to the bar to measure its push, and compare with the notebook.

**Edmund Brown** of Burlington, Chittenden County, Vermont, assignor to himself and Sylvanus Humphrey, filed US 148,660 on 24 January 1874; it is dated 17 March 1874. He notes the bar, teeth and lever may be cast in one piece of malleable iron with the holes punched by a power press. **Honest limits.** The notebook treats the band as a linear spring and the lever as rigid, and ignores friction on the teeth. The band stiffness, stretches and distances are examples. Your force-meter reading is the measurement.