Patent · US Expired

Level warning device

US4737759A · kind A · utility

17Cited by
10References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 1986
Grant dateApr 12, 1988
Priority date
Expiry dateAug 29, 2006

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60G2800/912
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A level warning device for dump trucks comprises a light transmissive tubular trackway having raised, closed ends and a mount for securing the tubular trackway to a transverse member of the bed of the truck. The trackway includes a detent at a central location which defines a pocket lateral of the passage defined within the trackway. The trackway itself comprises straight, tubular segments which are inclined with respect to a horizontal axis at angles equal to the critical angle at which the truck would likely start to turn over. Positioned above a central region of the trackway is a photo-electric switch. Optically aligned with the photo-electric switch from below the trackway is an element for emitting an infra-red beam through the tubular element. A ball which is sized to roll freely in the trackway and the pocket is held within the detent pocket while the bed is in a lowered position by reason of the inclination of the detent at such conditions. While in the pocket, a portion of the ball prevents the beam from striking the photo-electric switch.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.