Dump Truck Box with Reduced Tendency for Material to Stick at the Sides of the Box

Abstract

In a dump truck of the type having a frame mounted on ground wheels, a dump box having a floor, two side walls, a front wall at a front end and an open rear end with a tail gate where the dump box is supported on the frame for movement between a lowered position for storing and transporting materials and a raised position where the front end is elevated for dumping the materials out of the open rear of the dump box under gravity, the side walls are tapered so that a spacing at the front end is less than a spacing at the rear end so that the materials as they slide forwardly come away from the side walls to reduce pressure on the side walls and aid the sliding.

Claims

1. A dump truck comprising: a frame mounted on ground wheels; a dump box having a floor, two side walls, a front wall at a front end and an open rear end with a tail gate; the dump box being supported on the frame for movement between a lowered position for storing and transporting materials and a raised position where the front end is elevated for dumping the materials out of the open rear of the dump box under gravity; the tailgate being supported on the dump box for movement between a closed position, wherein the tailgate closes the open rear end of the dump box, and an opened position, wherein the tailgate is spaced away from the open end of the dump box for allowing discharge of the material; the side walls being tapered so that a spacing at the front end is less than a spacing at the rear end.

2. The dump truck according to claim 1 wherein a main part of each of the side walls is vertical.

3. The dump truck according to claim 2 wherein each of the side walls includes a bottom portion inclined to the floor and to the main part of the side wall.

4. The dump truck according to claim 1 wherein a width of the floor is tapered so that the floor at the rear end is wider than the floor at the front end.

5. The dump truck according to claim 1 wherein the side walls and the floor are metal so as to define a metal inside surface.

6. The dump truck according to claim 1 wherein the side walls are wider at the front by a distance in the range 5 inches to 30 inches and more preferably of the order of 6 to 10 inches.

7. The dump truck according to claim 1 wherein the box has a length of at least 20 feet.

8. The dump truck according to claim 1 wherein the box has a substantially constant height along a top edge of the side walls.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:

[0021] FIG. 1 is a perspective view of a dump truck including a first embodiment of a double cylinder assembly in accordance with this invention.

[0022] FIG. 2 is an isometric view of the box only of the truck of FIG. 1

[0023] FIG. 3 is an end elevational view of the box only of the truck of FIG. 1 showing the difference in dimensions of the rear end relative to the front end of the box.

[0024] In the drawings like characters of reference indicate corresponding parts in the different figures.

DETAILED DESCRIPTION

[0025] Referring now to the drawings, there is illustrated in FIG. 1 a dump truck, indicated generally at 10, including a frame that supports a dump box 11 that is pivotable by a hydraulic lift system 10A between a lowered position for storing and transporting items and a raised position as shown for dumping the items out of the dump box 11 through an open rear. The dump box 11 includes a floor 12, a pair of vertical side walls 13, a front wall 14, and an open rear end 15. The open rear end 15 of the dump box 11 has a pair of upstanding corner posts 16 that are each formed from a hollow rectangular member. A tailgate 17 is supported on the side walls 13 of the dump box 11 adjacent to the open rear end 15 for pivoting movement between a closed position wherein the tailgate 17 closes the open rear end 15 of the dump box 11 and an opened position wherein the tailgate 17 is spaced away from the open rear end 15 of the dump box 11, as shown in FIG. 1. The tailgate 17 is moved between the opened and closed positions by means of one or more single cylinders 18.

[0026] The dump truck further includes a frame 20 mounted on ground wheels 21 for transportation as a trailer or semi-trailer or on a rigid frame as shown by example.

[0027] The dump box is supported on the frame for movement between a lowered position for storing and transporting materials and the raised position shown where the front end is elevated for dumping the materials out of the open rear of the dump box under gravity over a rear discharge beam 23

[0028] The box being tapered so that a spacing S2 between the side walls at the front end is less than a spacing S1 at the rear end.

[0029] Each of the side walls 13 includes a bottom portion 13A inclined to the floor and to the main part of the side wall. The box has a substantially constant height along a top edge 13B of the side walls 13

[0030] A width of the floor 12 is tapered so that the floor at the rear end is wider than the floor at the front end.