Patents by Inventor Robert W. Lister

Robert W. Lister has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4616714
    Abstract: A soil perforator comprises a lightweight spiked rotor carried in a wheeled rectangular box-like frame with a handle secured to the rotor for manually pushing the assembled frame and rotor along the ground to provide soil aeration by perforation of the ground by the rotor spikes. The rotor may be vertically adjusted in the frame to vary the degree of spike penetration and to move the spikes out of ground engagement. The perforator further includes a detachable weight box to be mounted at one end of the frame opposite the handle, the weight box providing effective soil penetration by the spikes when the device is hitched by the handle to a vehicle and towed over the ground in the direction opposite to which it is manually pushed. Adjustable spring rake assemblies are provided at the opposite ends of the frame.
    Type: Grant
    Filed: December 17, 1984
    Date of Patent: October 14, 1986
    Inventor: Robert W. Lister