US 4,137,587 AGranted

Dockboard apparatus

OwnerKnut T. L. Rosengreninventor

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Abstract

A dockboard apparatus is disclosed in which a vertically displaceable chassis moves a pivotally mounted ramp between a vertical storing position and a horizontal working position. Skewing and binding of the chassis are prevented by a construction wherein a counterweight for the chassis is coupled to the chassis by first and second spaced hubs, such as chain sprockets, and first and second linkages, such as drive chains, connected between the chassis, hubs, and counterweight. To facilitate movement of the ramp into place, the support of the dockboard apparatus includes an upper support member having an upper rear part disposed substantially at the same level as the loading surface of the loading dock and an upper front part disposed substantially below the level of the upper rear part. This member may be embodied by an L-shaped beam with vertical and horizontal legs. The hubs are mounted on the upper front part, e.g., on the horizontal leg of the L-shaped beam. With this construction, the ramp may assume a pronounced forward, downward inclination from the loading surface of the loading dock during movement between the storing and working positions.

Claims4

Dependent claims

A dockboard apparatus for a loading dock having a horizontal loading surface and a vertical front wall, the apparatus comprising:

(a) a support;
(b) a vertically movable chassis on said support;
(c) a ramp pivotally supported by said chassis for movement between a substantially vertical storing position and a substantially horizontal working position;
(d) a counterbalancing means coupled with said chassis for facilitating manual movement thereof, the counterbalancing means including a counterweight;
(e) first and second linkage means each connecting said counterweight to said chassis;
(f) first and second hubs, said first hub being operatively coupled with said first linkage means and said second hub being operatively coupled with said second linkage means;
(g) said support including an upper support member which has an upper rear part disposed substantially at the same level as the loading surface of the loading dock, said upper support member also having an upper front part disposed substantially below the level of said upper rear part, said first and second hubs being mounted in spaced relationship on said upper front part;
(h) whereby said ramp may assume a pronounced forward, downward inclination from the loading surface of the loading dock during movement between said storing and working positions.

5 more elements

Dependencies are inferred from the claim text.