Front-of-dock dockboard
First Claim
1. A dockboard to be mounted on a loading dock having an upper surface and a front wall, comprising a generally rectangular frame disposed adjacent the front wall of the dock, guide means for mounting the frame for vertical movement relative to the dock, a pair of elongated tubular guideways disposed on said frame adjacent the sides thereof, a guide bar mounted for sliding vertical movement within each guideway, and a deck plate pivotally connected to the upper ends of the guide bars, said deck plate being liftable vertically from a first vertical lower storage position in which the deck plate is disposed generally vertically along the front wall of the dock to a second higher vertical position where at the lower end of the deck plate is above a bed of a carrier disposed adjacent the front wall of the dock so that the deck plate can be pivoted about said guide bars to a generally horizontal position and lowered to a cross traffic position to span the distance between the dock and the bed of said carrier with the rear end of the deck plate supported on the dock and thr forward end of the deck plate supported on the carrier, the forward end of the deck plate being biased downwardly so that the deck plate will assume a generally vertical position when the carrier is removed from its location adjacent the front wall of the dock and said deck plate will descend by gravity to said storage position, the sliding connection of the guide bars to said frame permitting the deck plate to tilt as a load passs over the deck plate when in the cross traffic position.
2 Assignments
0 Petitions
Accused Products
Abstract
A dockboard to be attached to the front of a loading dock. The dockboard includes a deck plate, the side edges of which are pivotally connected to guide bars that are movable vertically within guideways formed in the upper portion of a rectangular frame. The frame is mounted for vertical movement within guides mounted on the front face of the loading dock, and the frame and deck plate are partially counterbalanced to an upper position by a counterweight mechanism that is connected to the frame through a synchronized chain drive. The deck plate is stored in a vertical position below deck level and, in use, is lifted to a raised position above dock level, pivoted to a substantially horizontal position and then lowered into engagement with the bed of a carrier located in front of the dock. The pivotal connection between the deck plate and the guide bars enables the deck plate to tilt diagonally as a load moves across the deck plate in the event that the bed of the carrier is not parallel to the upper surface of the dock. When the carrier moves from the dock, the deck plate will swing to a vertical position and the frame will lower by gravity to move the deck plate to the vertical storage position.
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Citations
12 Claims
- 1. A dockboard to be mounted on a loading dock having an upper surface and a front wall, comprising a generally rectangular frame disposed adjacent the front wall of the dock, guide means for mounting the frame for vertical movement relative to the dock, a pair of elongated tubular guideways disposed on said frame adjacent the sides thereof, a guide bar mounted for sliding vertical movement within each guideway, and a deck plate pivotally connected to the upper ends of the guide bars, said deck plate being liftable vertically from a first vertical lower storage position in which the deck plate is disposed generally vertically along the front wall of the dock to a second higher vertical position where at the lower end of the deck plate is above a bed of a carrier disposed adjacent the front wall of the dock so that the deck plate can be pivoted about said guide bars to a generally horizontal position and lowered to a cross traffic position to span the distance between the dock and the bed of said carrier with the rear end of the deck plate supported on the dock and thr forward end of the deck plate supported on the carrier, the forward end of the deck plate being biased downwardly so that the deck plate will assume a generally vertical position when the carrier is removed from its location adjacent the front wall of the dock and said deck plate will descend by gravity to said storage position, the sliding connection of the guide bars to said frame permitting the deck plate to tilt as a load passs over the deck plate when in the cross traffic position.
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7. A dockboard to be mounted on a loading dock, said dock having an upper surface and a front wall, comprising a supporting structure mounted on the front wall of the dock, a generally rectangular frame disposed adjacent the front wall of the dock, guide means for mounting the frame for vertical movement on said supporting strucure, an elongated guideway disposed adjacent each side edge of the frame, a guide bar mounted for free vertical movement in each guideway, a deck plate having a front edge and a rear edge and a pair of side edges, means for pivotally connecting the side edge portions of the deck plate to the respective guide bars, counterweight means disposed along the front wall of the dock, a pair of chains, a pair of sprockets mounted at the upper end of the supporting structure and engaged with the respective chains, one end of each chain being connected to said counterweight means and the opposite end of each chain belong connected to the lower portion of said frame, a shaft to carry each sproket, said shafts being in general axial alignment, a connecting member connecting the adjacent ends of the shafts together whereby the chains will operate in synchronization as the counterweight means moves vertically to prevent skewing of said frame in said guide means, and means for permitting limited relative axial movement between each shaft and the connecting member.
- 8. A dockboard to be mounted on a loading dock having an upper surface and a front wall, comprising a generally rectangular frame disposed adjacent the front wall of the dock, guide means for mounting the frame for vertical movement relative to the dock, a pair of elongated tubular guideways disposed on said frame adjacent the sides thereof, a guide bar mounted for free sliding vertical movement within each guideway, and a deck plate pivotally connected to the upper ends of the guide bars, said deck plate being liftable vertically from a first vertical lower storage position in which the deck plate is disposed generally vertically along the front wall of the dock to a second higher vertical position where at the lower end of the deck plate is above the bed of a carrier disposed adjacent the front wall of the dock so that the deck plate can be pivoted about said guide bars to a generally horizontal position and lowered to a cross traffic position to span the distance between the dock and the bed of said carrier with the rear end of the deck plate supported on the dock and the forward end of the deck plate supported on the carrier, the forward end of the deck polate being biased downwardly so that the deck plate will assume a generally vertical position when the carrier is removed from its location adjacent the front wall of the dock and said deck plate will descent by gravity to said storage position, the sliding connection of the guide bars permitting the deck plate to tilt as a load passes over the deck plate when in the cross traffic position, and counterbalancing means interconnecting one of said guide bars and the deck plate for partially counterbalancing the weight of the deck plate to enable the deck plate to be pivoted to said generally horizontal position with a lesser manual force.
Specification