Road structure – process – or apparatus – Process
Reexamination Certificate
1999-08-06
2002-07-23
Will, Thomas B. (Department: 3671)
Road structure, process, or apparatus
Process
C404S101000, C404S102000, C198S317000, C198S318000
Reexamination Certificate
active
06422785
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to track driven belt placers for conveying construction materials to a graded surface during construction.
2. Description of the Prior Art
Belt placers are commonly used as the first step in a four-step paving process. First, the road bed is cleared, prepared and graded.
Second, belt placers travel via track assemblies slowly and longitudinally along the paving direction, conveying construction materials, usually wet concrete, from a concrete supply truck to the graded road bed. The wet concrete is first loaded onto an infeed conveyor belt. This belt is capable of folding upward by use of an elbow joint, allowing trucks to drive past the belt prior to unloading the wet concrete or other construction material. This capability allows all of the trucks to travel in a straight line, creating safer and more efficient paving projects.
Next, the infeed conveyor belt conveys the wet concrete to either a second belt the discharge conveyor belt, or a spreader auger. Either the discharge conveyor belt or the spreader auger uniformly spreads the wet concrete across the graded road bed.
The third step of the paving process involves leveling, compacting, and forming the wet concrete through use of a slipform paver. Optionally, the fourth step cures and textures the wet concrete by use of a third machine. Typically these machines operate in close tandem, in order to avoid too much concrete setting during the road forming process.
After a truck pulls past the infeed conveyor belt, the truck is ready to discharge its load of concrete onto the infeed conveyor belt. Because the truck discharge is designed to quickly transfer large amounts of wet concrete to the belt placer, the transfer is not a precision operation. For example, belt placers are capable of handling approximately twenty (20) cubic yards in a minute. Invariably, the concrete splashes around the work area and eventually solidifies on the equipment. This has the undesirable consequence of hardening on some of the equipment that must maintain mobility in order to function properly. To prevent some of the concrete untidiness, fixed and manually pivoting skirting is used to protect some of the rollers underneath the belt and to facilitate lubrication of the rollers.
Traditionally, infeed conveyor belts are capable of folding upward to allow the concrete supply truck to drive a straight path on a haul road or adjacent pavement and pass the infeed conveyor belt prior to loading the belt placer. This capability works well to increase the speed of the paving process, but only if the supply truck is at the same elevation as the belt placer. If the supply truck is on a haul road or adjacent pavement that is not level with the surface that the belt placer is traveling, the infeed conveyor belt often bottoms out because the supply truck is usually higher than the graded surface. Alternatively, some belt placers are capable of raising or lowering one side of the machine in an attempt to level the machine with the haul road or adjacent pavement.
On the discharge end of the belt placer, discharge conveyor belts traditionally have the capability of rotating approximately 40°. This rotational capability allows the operator to spread the wet concrete more evenly and efficiently across the graded bed. However, this limited range of rotational capability does not work well if the belt placer has to place concrete across the entire length of an obstacle oriented perpendicular to the paving direction, such as a trench crossing. Alternatively, augers are used to spread the wet concrete in an even and efficient manner. Both of these methods prove useful for paving in one direction, and when few paving obstacles exist.
However, in order to change paving direction, the operator would have to turn the bulky and cumbersome machine around, once again decreasing efficiency. These mobilizations prove costly and time consuming, as well as presenting an element of risk to worker safety.
SUMMARY OF THE INVENTION
In order to solve the foregoing shortcomings of traditional belt placers, the invention herein relates to improved belt placers.
According to one aspect of this invention, an infeed conveyor is provided with high pivot capability. High pivot capability is the capability to raise the conveyor belt folding point, and thus the distal end of the infeed conveyor to an elevation of up to and exceeding 22″ higher than regular horizontal operation if the belt placer is operating lower than the surrounding grade. High pivot capability prevents the infeed conveyor from bottoming out on the grade of the haul road or adjacent pavement; and in some instances, high pivot capability allows use of the belt placer under conditions that belt placers without high pivot capability could not operate.
An infeed conveyor for conveying construction materials from a truck is disclosed, the infeed conveyor comprising: an endless conveyor belt with a folding point, and means for raising and lowering the folding point to provide high pivot capability for the infeed conveyor.
A method of conveying construction material from a truck situated on a haul road or adjacent pavement with a grade higher than a grade that a belt placer travels on is also disclosed, the method comprising: pivoting an infeed conveyor to raise at least a portion of the bottom of the infeed conveyor to a height above the grade of the haul road or adjacent pavement; folding an infeed conveyor from a horizontal to a vertical position; allowing a truck to drive past the infeed conveyor; unfolding the infeed conveyor from the vertical to the horizontal position; and receiving construction material from the truck onto the endless conveyor belt. If the infeed conveyor has a folding point, the method can include raising the folding point of the infeed conveyor.
A high pivot assembly for raising an infeed conveyor on a belt placer is also disclosed, the high pivot assembly comprising: a high pivot leg, a lifting means, and an infeed conveyor support means. Such a high pivot assembly could include a lower lifting support, an upper lifting support, an under-conveyor support aperture, a pin, a lower lifting mechanism aperture, an immobile shaft, and an upper lifting mechanism aperture; wherein the lower lifting support is coupled to the upper lifting support, the under-conveyor support aperture creating a void through the lower lifting support, the pin coupled through the under-conveyor support aperture, the lower lifting mechanism aperture creating a void through the upper lifting support and providing a space for the lifting means to attach and lift, the immobile shaft coupled with the upper lifting support and providing the upper lifting support with a conduit for vertical movement, the upper lifting mechanism aperture creating a void through the immobile shaft and providing a space for the lifting means to attach and suspend.
According to another aspect of this invention, belt placers can now be used to pave in both forward and reverse directions, whereas former belt placers could only pave in the forward direction. This is accomplished by the ability to rotate the discharge conveyor under one side of the belt placer, and changing the direction in which the belt placer travels. According to this aspect of the invention, this belt placer now has no universal front and no true back. Both sides of the machine can act as the front of the machine: the traditional front of the machine acting as the front of the machine when the discharge conveyor is facing forward and the belt placer is operating in the forward direction, and the traditional front of the machine acting as the back of the machine when the discharge conveyor is rotated to the back side of the machine and the belt placer is operating in the reverse direction.
A belt placer for conveying construction materials is disclosed, the belt placer comprising: an infeed conveyor and a discharge conveyor, and means for rotating the discharge conveyor from a position of first discharge directi
Rohrer David C.
Ruggles Thomas A.
Addie Raymond W
Rexcon-Division of Rose Industries, Inc.
Ryan Kromholz & Manion S.C.
Will Thomas B.
LandOfFree
Track belt placer for placing construction materials and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Track belt placer for placing construction materials and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Track belt placer for placing construction materials and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2868484