Road structure – process – or apparatus – Apparatus – Automatic control
Reexamination Certificate
2002-06-05
2004-08-10
Will, Thomas B. (Department: 3671)
Road structure, process, or apparatus
Apparatus
Automatic control
C404S101000, C404S118000
Reexamination Certificate
active
06773203
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to a paving machine, more particularly a machine for spreading and levelling concrete, as well as to a method for forming a concrete path.
As known, such paving machines are used for forming a variety of concrete pavings, in the first place for forming concrete roadways, but, furthermore, also for forming large concrete floors and such.
It is known that such paving machines mostly consist of a movable frame at which one or more processing devices for processing the concrete are fixed or can be fixed. Mostly, use is made of several processing devices providing for different processings, such as spreading the concrete, which has been poured in front of the device, in width, vibrating the concrete, drawing the concrete into a shape, providing dowels in the concrete, smoothing the concrete by means of a smoothing beam and finishing by means of a smoothing board moving to and fro.
It is also known that such paving machines, including the processing devices, can be made extensible in order to be able to adjust the working width. An example thereof is known from the international patent application WO 95/28525. In such case, the frame as well as the processing devices are telescopically extensible, whereby the processing devices then consist of several parts which telescope either in each other or along each other or at a distance behind each other.
Such paving machines, the processing devices of which consist of several parts which together must span the working width, and especially paving machines with parts which, as aforementioned, are extensible in respect to each other, show the disadvantage that the mutual position of the parts of one and the same processing device may change during paving, as a result of sagging under the weight of the paving machine and/or as a result of the pushing in upward direction, when, centrally below the paving machine, a surplus of concrete is poured. This has as a consequence that the surface of the formed concrete path deviates from the desired shape. It has already been proposed to remedy this by using manually turnable screw jacks with which the mutual position of the aforementioned parts can be adjusted. This solution, however, has the disadvantage that it is less efficient, as in practice an adjustment exclusively will be carried out when major, visually discernible deviations occur.
Further, it is also known that paving machines can be equipped with oscillating finishing beams for assisting in smoothing the concrete of the path surface. An example thereof is described in U.S. Pat. No. 5,941,659, in which two finishing beams, situated at a distance from each other according to the direction of movement, are applied, i.e. one finishing beam performing a substantially vertical oscillation, and a finishing beam performing a substantially horizontal oscillation. The vertical oscillation has as a purpose, so to speak, to tamper the gravel in the concrete into the surface, whereas the horizontal oscillation additionally smoothes the concrete at the surface. In that hereby use is made of two oscillating finishing beams cooperating with one and the same path surface, such embodiment, however, shows the disadvantage that the average positions which are taken by these finishing beams in respect to the formed path surface, have to be precisely coordinated in mutual respect, and that, with certain deviations, malfunctions in the faultless working may occur. Another disadvantage consists in that two separately driven systems, one behind the other, are necessary, as a result of which the total length of the paving machine, seen according to the paving direction, is influenced in a disadvantageous manner.
The present invention aims at a paving machine, whereby various improvements are intended which contribute to a better quality of the obtained concrete path and/or which allow for performing a more efficient control of the quality of the realized concrete path.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, a paving machine is aimed at, with one or more processing devices consisting of two or more parts which together span the working width, whereby a solution is offered for efficiently excluding or minimizing deviations in the surface of the concrete path which arise as a consequence of undesired alterations in the mutual position of such parts. More particularly, according to this first aspect, it is aimed at excluding or at least minimizing undesired deviations as a result of the sagging of the paving machine and/or the pushing-up of parts thereof.
According to this first aspect, the invention thus relates to a paving machine, comprising a movable frame with at least one processing device for processing the concrete which extends according to the working width and which consists of at least two parts,or otherwise called screed elements, which possibly are movable in respect to each other, in order to adjust the span of the processing device, with as a characteristic that the paving machine comprises means, or otherwise called a control device, on one hand, directly or indirectly, control the mutual position of said parts, such in respect to the surface to be formed, as well as, on the other hand, allow for adjusting the mutual position in function of said control.
By providing the paving machine with means which, on one hand, allow for such control and, on the other hand, allow for an adjustment, a very precise follow-up of the mutual position of said parts is possible, and it is possible to rapidly take measures in order to remedy any undesired alteration in the position by means of a corresponding adjustment.
Preferably, said means consist of detection means or otherwise called a detection device, performing observations in respect to said mutual position, as well as controllable adjustment means, or otherwise called an adjustable device, for commanding said parts in such a manner that a desired adjustment is realized. More particularly, it is preferred that the controllable adjustment means are coupled to the detection means, such that an adjustment is performed in function of a desired adjustment of the mutual position. Thereby, an automatic feedback is provided for, whereby the operator of the paving machine himself no longer has to perform any adjustments.
Although the invention allows to counteract a variety of deviations between the positions of the respective parts of a processing device, it is clear that said means, in the first place, are intended to control the sagging, pushing-up, respectively, of the processing device.
In a practical form of embodiment, the frame of the paving machine, as usual, comprises two side parts carried by movable support elements, and according to the present invention, said means are configured such that they provide for a control in respect to a reference line, reference plane, respectively, which connects the two side parts. In practice, paving machines in fact are kept at a well-defined height at these side parts, for example, by means of sensors which command the height of the side parts in function of pre-set level lines. In the proximity of the side parts, the obtained concrete path thus always is at the right height, and lines or planes connecting the two side parts therefore ideally may serve as a reference line or plane for performing said control.
In the case that use is made of such reference line or such reference plane, said parts, at their outwardly directed extremities, are connected to the side parts preferably at a well-defined height, whereas with their inwardly directed extremities, they can be adjusted in height by means of said controllable adjustment means. When the paving machine is realized in a classical manner, with a central basic frame and with side parts provided on frame parts which are extensible in respect to the basic frame, it is preferred that the controllable adjustment means are situated between the basic frame and said two parts of the processing device. As a result thereof, said parts can be easily d
Bacon & Thomas PLLC
Drion Constructie, besloten vennootschap met beperkte aansprakel
Pechhold Alexandra K.
Will Thomas B.
LandOfFree
Paving machine and method for forming a concrete path does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Paving machine and method for forming a concrete path, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Paving machine and method for forming a concrete path will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3321398