Multi-use paving tractor with tool attachments

The present invention generally relates to road paving equipment, and more particularly relates to pavers, and even more particularly relates to pavers with a capability for remixing hot mix asphalt (HMA) material placed in the hopper onboard the paver.

BACKGROUND OF THE INVENTION

In the past, road paving equipment designers have endeavored to improve the functionality of road pavers. U.S. Patent 6,007,272 is an example of an improved paver with mixing capabilities. While such improvements have been made to remixing capabilities of pavers, they remain a single use machine. Most paving contractors will have a paver, a road widener and some means for transferring the mix to the paver and road widener, all of which are independent machines.

While these approaches of using independent pavers, road wideners and mix transfer machines, etc. have been used extensively in the past, they do have some drawbacks. First of all, they require significant investment. Secondly, they require considerable space for storage and transportation.

Consequently, there exists a need for improved methods and systems for deploying multiple paving equipment tools.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a system and method for deploying multiple paving equipment tools in an efficient manner.

It is a feature of the present invention to utilize a multi-use paving tractor.

It is an advantage of the present invention to reduce the cost of owning a group of paving tools.

It is another advantage to permit multiple paving equipment tools to be stored in a smaller space.

It is yet another advantage to permit reduced transportation costs in moving several paving tools to a job site.

The present invention is an apparatus and method for deploying multiple paving tools, designed to satisfy the aforementioned needs, provide the previously stated objects, include the above-listed features, and achieve the already articulated advantages. The present invention is carried out in a "redundant hardware-less" manner in a sense that the need to own, maintain and transport multiple paving hoppers, remixing equipment and propulsion mechanisms for a group of road paving tools, has been eliminated.

Accordingly, the present invention is a system and method including a paving tractor with a capability for readily connecting and disconnecting a road paving tool thereto.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more fully understood by reading the following description of the preferred embodiments of the invention, in conjunction with the appended drawings wherein: <ul id="ul0001" list-style="none"><li>Figure 1 is an elevation view of the multi-use paving tractor of the present invention, with a partial cut-away portion to reveal a plurality of augers.</li><li>Figure 2 is an elevation view of the paving tractor of Figure 1, having an attached mix transfer tool.</li><li>Figure 3 is an elevation view of the paving tractor of Figure 1, having an attached road widener tool.</li><li>Figure 4 is a partial top view of the paving tractor and road widener tool of Figure 3.</li><li>Figure 5 is an elevation view of the paving tractor of Figure 1, having an attached screed.</li></ul>

DETAILED DESCRIPTION

Now referring to the drawings wherein like numerals refer to like matter throughout, and more specifically referring to Figure 1, there is shown a multi-use paving tractor of the present invention, generally designated 100, which includes a hopper and mixing apparatus 101, a conveying shaft 102, auger 109, driver station 120, driver seat 122, steering wheel 124, engine 126, chassis 127 and drive train 128. Items 101, 102, 109, 122, 124, 126, 127 and 128 are preferably similar or identical to components of prior art remixing road pavers such as described in the above- referenced U.S. patent and the prior art road paver manufactured by Cedarapids, Inc. of Cedar Rapids, Iowa. Engine 126 is drawn as a simple block, but it may include numerous related systems and/or components not limited to components of a hydraulic pump and system, an electrical system and other systems. One of the key aspects of these prior art pavers is that they do not exhibit the characteristics of dropping or dribbling asphalt from a return conveyor under the machine as is common in other prior art pavers. The elimination of dribbling from underneath the prior art paver was not perceived as a significant benefit because that machine and the machine described in the above-referenced patent were both dedicated pavers. Dribbles on the ground in front of a paver were not a problem because the paver covered these dribbles as the paver progressed forward. However, for the present invention, it is desirable that the tractor 100 not dribble asphalt on the ground as it progresses forward. The non-dribbling configuration of the above-referenced patent and the above-described paver is preferred. However, it should be understood that any other non-dribbling or low-dribbling mechanisms could be used in conjunction with the remainder of the present invention.

A pull arm 103 is shown coupled to the tractor 100. Preferably a pull arm 103 is disposed on each side of the tractor. Pull arm 103 may include a quick connector 1032 disposed on or near a rear end 1031 of the pull arm 103. Pull-arm quick connector 1032 could be numerous types of connectors, such as a butt plate with holes for receiving bolts or pins, a channel for receiving an insert dropped in from above, a male or female connector, etc. Pull arm quick connector 1032 may have additional connectivity capability beyond structural connections, such as electric connections, hydraulic hose connections, etc. In any case, it is preferred that pull arm quick connector 1032 provide for the ability to add or remove attachments very quickly and while in the field. Preferably, no welding or powered tools, other than those receiving power from the multi-use paving tractor 100 and a lift used to move the attachment, would be necessary. Hydraulic cylinders 1034 and 1035 or other mechanism for manipulating pull arm 103 between various raised and lowered positions are also shown. In a preferred arrangement, the pull arm 103 can be raised or lowered to engage tool attachments, discussed in detail below. While it may be preferred to utilize dual pull arms 103 on each side, it should be understood that a centrally disposed pull arm or group of centrally disposed pull arms could be used as well. The pull arm 103 is preferably movable, but it should be understood that it could be a simple fixed connection point disposed on the tractor 100. An upper link 104 could be another connection between the tractor 100 and tool attachments. Upper link 104, if hydraulically extendable and retractable, could be used to connect, position and otherwise manipulate any tool attachment coupled to pull arm 103.(Note: that the upper link 104 may not be used on some attachments such as the screed.) An upper link 104 may be disposed on either side of the tractor 100, or a single upper link could be used as well. Appropriate driver controls 125 may be included to assist in the manipulation of pull arm 103 and upper link 104.

A more detailed understanding of the present invention can be achieved by now referring to Figure 2, which shows a multi-use paving tractor 100 of Figure 1, together with an HMA mix transfer tool attachment, generally designated 200, which includes an elevator assembly 205, which collects remixed HMA from the rear of conveying shaft 102 and hopper and mixing apparatus 101 and elevates the HMA. Elevator assembly 205 includes elevator assembly lower connecting floor 206, which seals the elevator assembly 205 to the rear of the conveying shaft 102. Elevator assembly lower connecting floor 206 is where the HMA is collected prior to being elevated above the conveying shaft 102 by the elevator assembly 205. Elevator assembly slat conveyor 207 is shown disposed in elevator assembly 205. It should be understood that the depicted arrangement of elevator assembly 205 is a preferred embodiment of the present invention. Alternate means and methods of elevating the HMA could be employed, such as augers, pumps and pipes or hoses, etc. The purpose of elevator assembly 205 is to collect the HMA and deliver it to swinging slat conveyor 209. However, it should be understood that elevator assembly 205 or its alternate means could be adjustable vertically and radially so as to eliminate the need for swinging slat conveyor 209.

In this preferred embodiment, swinging slat conveyor 209 is a vertically and radially adjustable conveyor which can be swung to the right or the left upon swinging slat conveyor pivot support 211, which can be a hinge or other pivot support. Swinging slat conveyor 209 includes a swinging slat conveyor interior chain assembly 208 and a swinging slat conveyor raising mechanism 210 which can be disposed on one pull arm 103 or one side of the multi-use paving tractor 100, or it can have one on each side of multi-use paving tractor 100 or attached to right and left pull arms 103. Swinging slat conveyor raising mechanism 210, if mounted to a side of multi-use paving tractor 100, can both raise swinging slat conveyor 209 and swing swinging slat conveyor 209 right and left as needed. Swinging slat conveyor raising mechanism 210 can be a hydraulic cylinder, a cable/winch system or other system for lifting and swinging the swinging slat conveyor 209.

Swinging slat conveyor pivot support 211 is preferably a support for pivoting about a horizontal axis and a vertical axis. A rotational coupling or independent orthogonal pivots could be used to enable swinging slat conveyor 209 to be both raised and swung as needed.

An even more detailed understanding of the present invention may be achieved by now referring to Figures 3 and 4, which shows a right- or left-sided road widener attachment 300, which is preferably attached to multi-use paving tractor 100 via pull arm 103. In this figure, elevator assembly 205 is used to elevate the HMA for distribution to a chute or cross conveyor 302. The HMA is then distributed alongside the multi-use paving tractor 100 so as to provide for road widening by road widener strike-off blade 417. The road width extension dimension 414 can be adjusted by manipulation of road widener strike-off blade angle control link 415, which controls the angle of road widener strike-off blade 417. The HMA is partially contained by road widener end gate assembly 413, which is adjusted by manipulation of road widener end gate angle control link 416. Right- or left-sided road widener attachment 300 is shown with few details because it is believed that numerous right- or left-sided road widener attachments 300 could be designed to meet the peculiar needs for various road types. It is believed that a person skilled in the art of making road wideners could readily adapt the above-described concept to work with most any particular road widening project type. For example, road widener strike-off blade 417 could be made to pivot about both a horizontal axis and a vertical axis.

Figure 5 shows a multi-use paving tractor 100 with a paver screed 518 attached thereto. It is believed that one skilled in the art given the description of the present invention could develop various paver screeds 518 to meet particular needs of various paving job types.

In operation, the apparatus and method of the present invention as described in Figures 1-5, could function as follows:

Firstly, a multi-use paving tractor 100 is provided which accepts HMA in a hopper and mixing apparatus 101 and transports it rearward via conveying shaft 102.

One of several attachments, such as HMA mix transfer tool attachment, right- or left-sided road widener attachment 300 or paver screed 518 could be attached to the multi-use paving tractor 100, depending upon the needs at the time. The combination is then deployed and used on a road. The attachment then is removed and replaced with another of the several attachments and the new combination is used. Numerous road-paving tools can be deployed on one job without the need for redundant components. The removal and replacement process preferably can be done by either using a lift to pick up the attachment or raising the attachment and backing the multi-use paving tractor 100 to a trailer or platform where the attachment is then lowered and disconnected.

Throughout the above description, HMA is described as the material to be used. It should be understood that the present invention is directed to any type of road surface. It is believed that recycled asphalt products could be used, cold mix asphalt, and even in certain applications with any appropriate modifications, concrete could be the paving material. Hopper and mixing apparatus 101 may comprise a rectangular box or an angled rectangular or circular bin or any shaped container and material mixing and transfer apparatus which is suitable for the paving material being used.

It is thought that the method and apparatus of the present invention will be understood from the foregoing description and that it will be apparent that various changes may be made in the form, construct steps, and arrangement of the parts and steps thereof, without departing from the spirit and scope of the invention or sacrificing all of their material advantages. The form herein described is merely a preferred exemplary embodiment thereof.