3 Matching Results

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Cotton-Chopping Machine. (open access)

Cotton-Chopping Machine.

Patent for a cotton chopping machine, which can be attached to a cultivator, has a mechanically operated hoe, and automatically changes its cutting height for different heights of ground.
Date: May 31, 1910
Creator: Martin, John M.
System: The Portal to Texas History
Car-Coupling. (open access)

Car-Coupling.

Patent for a car-coupling that has a draw-bar attached to the car, a hollow draw-head with a flaring opening that sits horizontally to the draw-bar, a spring that holds the draw-head in the horizontal position, a bar that raises and lowers the forward end of the draw-head against the spring, a coupling-pin that sits in the draw-head, a chain that connects the draw-head to the bell-crank lever, a cam that supports the chain, and a device that turns the cam in either direction in order to tighten the chain.
Date: March 31, 1896
Creator: Epps, Charles
System: The Portal to Texas History
Dental Impression-Tray. (open access)

Dental Impression-Tray.

Patent for improvements in dental impression trays that is adaptable for when there is only one or a partial set of teeth. There is a separate, smaller dental impression tray that is easily accessible and can be adapted to take impressions of one tooth or partial teeth.
Date: August 31, 1920
Creator: Littlejohn, Thomas F.
System: The Portal to Texas History