1
Cliff Harper: Foldable trailer. Burke Robertson, November 22, 1988: US04786073 (48 worldwide citation)

A foldable trailer having a frame and platform which are laterally divided into a front, rear and central section, the axle of the trailer being secured to the central section. The central section is pivotally connected respectively to the front and rear sections so that the front and rear sections ...


2
Cliff Harper: Activity kit. Berman Aisenberg & Platt, June 6, 1989: US04836783 (29 worldwide citation)

An activity kit for drawing, painting, sewing or the like, comprising a rigid case providing a flat activity surface and a cavity within the case for receiving a roll of medium, such as paper on which the activity is to be carried out. Medium from the roll is fed between medium guide positioned on t ...


3
Eric Goldberg, Cliff Harper: Methods, systems, and software for providing a blocked sewer alert. Keegan M Caldwell, Micah T Drayton, March 20, 2018: US09920511

A blocked sewer unit includes a substantially impermeable barrier having a first side exposed to the interior of a sewage network and a second side, the barrier movable in the direction of the second side in response to fluid pressure on the first side. The blocked sewer alert unit includes a transd ...