The present invention relates generally to mechanized pavers for compacting and densifying raw or wet concrete when forming supportive decks. More particularly, the present invention relates to concrete pavers for shaping and finishing rail trackbeds characterized by multiple, parallel, plinth strips separated from and/or bordering multiple, parallel, channel floors.
Modern “light-rail” train systems offer numerous well-known transportation advantages and efficiencies to urban environments. Light rail systems provide a form of tramway or urban rail transit, using rolling stock. They operate at a higher capacity than most historical tramways, and are often formed on an exclusive right-of-way in potentially congested commuting areas. In use, either individual tramcars or multiple units are coupled to form a train that is of lower capacity and lower speed than a conventional, heavy-rail passenger train or metro system. A few light rail networks tend to have characteristics closer to rapid transit; some of these heavier, rapid transit-like systems are referred to as light metros. Other light rail networks are tram-like in nature and partially operate on streets.
Light-rail systems of course include elongated stretches of rails, which are placed over suitable supporting trackbeds constructed along dedicated pathways. A typical trackbed comprises lower layers of ballast and sub-ballast prepared over a subgrade. A properly constructed trackbed can significantly improve the ride quality experienced by passengers. The trackbed's uppermost, exposed outer deck usually comprises concrete, which may be laid down and shaped by concrete finishing and placement machines known in the art. Suitable raised concrete projections, comprising slightly elevated blocks or slabs known as plinths, can be formed for supporting steel rail tracks and their mounting hardware, which are secured to the trackbed as the construction process progresses.
It is well recognized in the art that wet or plastic concrete must be processed or finished soon after pouring and before significant hardening to achieve desirable characteristics. Wet concrete is normally discharged from above and poured between spaced-apart forms that may border and traverse regions to be paved, such as bridge decks and the like. Usually wet concrete is poured immediately in front of a concrete finishing machine that may be supported by spaced-apart concrete forms that function as supporting guide rails for the machinery. For best results, it preferred to vigorously vibrate green concrete during pouring to facilitate desirable concrete consolidation. A variety of finishing devices such as strike-offs, screeds, vibrating screeds, roller screeds or pavers, and bridge deck pavers are known in the concrete arts. Various propulsion means may be employed for machine displacement over supports for travel along the deck length.
The concrete deck forming the top of the trackbed can be formed, but not without difficulty, with various bridge deck and concrete placement apparatus. The concrete deck may comprise at least a pair of parallel, spaced apart, plinth strips for supporting pedestal-like plinth structures that are subsequently formed atop the concrete structure. Completed plinth's are formed with elevated, box-like support forms that surround rebar stirrups emanating from the previously established plinth pathways. Smoothed channels usually comprising a squarish or rectangular profile are preferably formed between the plinths. These channels may be shaped or interiorly contoured for a variety of reasons, such as supporting drainage scuppers at the reduced elevation centers of one or more of the channel floors. Once the plinths are finished, the bordering channel floors form the bottom of troughs that extend along and adjacent to the plinths.
Plinth strip rebar stirrups provide an attachment means for the subsequently attached rail mounting hardware and the various rails themselves. After the concrete hardens, the various rail supporting hardware items, including fasteners, support plates, dampening layers and the like are fastened atop the plinths and interconnected with rebar prior to installation of the train rails.
Automated concrete finishing and forming machines for quickly and efficiently laying down significant lengths of trackbed concrete, with a proper arrangement of plinth and channel structures, are thus desirable. However, known concrete finishing machines of conventional construction are not particularly adept at the latter function.
Allen Engineering Corporation has previously developed concrete finishing machines that can use rigid, horizontally disposed, support frames, such as box frames or triangular truss frames. These can support various tool arrangements that hang down and contact wet concrete. Allen U.S. Pat. No. 4,249,327, for example, discloses a rigid, elongate triangular truss frame.
Besides well-known screed and strike-off elements, rollers are known. For example, a roller-tube finishing machine is seen in U.S. Pat. No. 4,314,773 issued Feb. 9, 1982 and owned by the present assignee. It discloses a form-riding, concrete placement and finishing machine comprising multiple roller tubes, that is positioned above an area into which wet concrete has been poured, for vibrating the concrete mass and finishing the concrete surface.
U.S. Pat. No. 4,702,640 issued Oct. 27, 1987, and also owned by Allen Engineering Corporation, discloses another rotating-tube type concrete finisher.
U.S. Pat. No. 5,562,361 issued to Allen Engineering Corporation Oct. 8, 1996 discloses a powered, form-riding, concrete finisher that uses a trio of rotating tubes to strike-off, screed and finish concrete.
U.S. Pat. No. 5,352,063, issued to Allen Engineering Corporation on Oct. 4, 1994 discloses a concrete finisher entitled “Polymer Concrete Paving Machine.” The latter machine comprises a self-propelled paver that distributes, consolidates, places and finishes polymer concrete to resurface roadbeds. A finishing assembly secured upon a supportive chassis includes a distribution assembly for applying concrete transversely across a surface, and a trailing finishing screed that densifies the concrete. The finishing screed comprises a rigid strike off that initially contacts uncompacted concrete laid by the distribution system. However, none of that machine's accessories or parts are configured or designed to shape rail trackbeds.
While the previously discussed finishers such as roller tube finishers are ideal for certain concrete structures, like bridge decks and floors of “big box” stores, etc., they are impractical for rail trackbed projects because of the alternating plinth's and voids needed in a rail trackbed deck. Numerous other concrete placement machines of diverse forms have been patented by the present assignee, but none are particularly relevant to the construction of concrete rail beds where plinth strips and intermediate channels are required. For example, there are numerous types of strike-offs in use, such as the designs seen in U.S. Pat. No. 5,476,342, owned by the same assignee as in this case.
However, applicant is unaware of any concrete forming machine designed for the specific application of treating and forming concrete trackbed decks, with their plinths and parallel channels. Providing concrete finishing apparatus especially configured for dealing with alternating plinth's and channels needed in a rail trackbed deck is the goal of this invention.
A concrete finishing and forming machine adapted especially for rail trackbed deck construction, accommodates the subsequent completion of various plinths and channels needed for light rail construction.
The highly versatile and adjustable machine is quickly adaptable to a wide variety of deck configurations and sizes, and may be adjusted at the job site to accommodate varying trackbed paths, inclinations, and angular pathways. The machine preferably comprises an elongated, horizontally extending box or truss frame disposed above the deck by preferably four, vertically upright, adjustable jack stands. In one configuration a jack stand is positioned at each machine corner. The jack stands are supported at their bottoms by wheeled bogies. Preferably the bogies rest upon upon suitable supports, such as travel rails, provided at opposite sides of the intended deck location prior to concrete treatment. Gross frame and machine displacements along the deck pathway are enabled by the hydraulically powered bogies so the machine can move over and along the trackbed as concrete is configured.
The jack-stands enable frame support vertically above the lower concrete workpiece at a user-selected height. The upper portions of the jack-stands are rigidly connected to supporting swing arms that extend from a rigid, vertically disposed pivot sleeve, that enables the jack stands to assume varying positions angularly swung out relative to the frame. The pivot sleeves are mounted to sleeve brackets that include rollers engaging tracks on the frame, enabling gross adjustments to the frame position by sliding the frame through desired displacements into a correct spacing relative to the jack-stands and thus the lower deck (i.e., the deck segments).
Preferably the frame supports an internally fitted, slidable carriage that can be displaced longitudinally relative to the frame. Carriage wheels engage frame tracks for displacement relative to the frame, enabling precise position adjustments. The carriage supports at least one downwardly extending, longitudinally displaceable paving head that, when immersed within wet concrete below and horizontally drawn along as the machine moves over its supports, strikes off elongated, smoothed channels resembling pathways upon the concrete. Elongated, spaced apart, unfinished plinth strips are concurrently formed between the smoothed channels. Preferably the paving heads are slidable relative to the carriage, and suspended by head wheels that engage the carriage for establishing yet another means for longitudinal position adjustments necessitated by the precision required for safe rail construction.
The rough plinth strips include projecting rebar stirrups that extend upwardly and outwardly from the strips. The stirrups penetrate subsequently formed, concrete plinth structures that directly support and receive the train rails and their rail mounting structure. Concrete forms properly positioned on the plinth strips shape the resulting plinths, after concrete fills the forms. Thus the stirrups end up immersed within the upright, concrete plinth structures that are subsequently formed atop the initially formed plinth strips after the instant machine completes its work. During its operation the preferred machine clears the plinth strip stirrups, and moves along over the deck without contacting the stirrups, while providing smoothed and properly contoured channels or pathways between the plinth strips. After construction these channel pathways occupy the bottom of troughs adjacent the plinths, forming floor bottoms or scuppers as desired.
Thus, it is a basic object of the present invention to provide a self-propelled concrete finishing machine for constructing light rail systems.
Another object is to efficiently lay down and finish concrete rail beds or trackbeds.
Another basic object is to provide a machine of the character described that smoothly establishes elongated, profiled channels between adjacent plinth regions.
It is also an object to provide a deck finishing machine of the character described that screeds and finishes concrete voids between plinth regions.
Another basic object of the present invention is to enable field adjustments to adapt the machine of the character described to rail trackbeds of different sizes and configurations.
Another important object of the present invention is to provide a concrete finishing machine of the character described that includes a control panel that can be switched between machine sides for moving different directions, obviating the necessity of hoisting and then rotating the entire machine for reversing the work direction. It is a feature of this machine that a plurality of quick-connect/disconnect hydraulic fittings enable quick reversing of the machine control position without hoisting and rotating.
A still further object of the invention is to provide a concrete finishing machine of the character described including a rigid, supporting truss assembly extending over the desired rail bed for supporting horizontally and vertically adjustable and spaced-apart paving heads that engage the lower concrete surface for deck finishing.
Another object is to provide a concrete finishing machine of the character described that can be adjusted to tilt the paving heads as desired to vary the configuration of the channels.
These and other objects and advantages will appear or become apparent in the course of the following descriptive sections.
In the following drawings, which form a part of the specification and which are to be construed in conjunction therewith, and in which like reference numerals have been employed throughout wherever possible to indicate like parts in the various views:
With primary reference now directed to
As illustrated, deck 52 (
With joint reference now directed to
Multiple frame segments 54B of varying lengths can be coupled together longitudinally to form the frame 54 of varying frame lengths. To this effect, it is to be noted that the bottom of each frame segment 54B (
The elongated carriage 80 is slidably suspended from frame segment tracks 135, 136 discussed earlier. The carriage comprises a pair of spaced apart, rigid side bars 150 and 152 (
The paver 50 has a plurality of upright, adjustable jack stands 200 described in detail below for support and locomotion. There preferably are four jack stands, one at each corner of the paver 50 (
With joint primary reference directed now to
The outermost side of a jack plate 206 is best seen in
In some cases it is helpful to be able to radially shift the position of the jack-stands 200 for clearance purposes, so the swing-out assembly 208 (
A typical paving head 70 discussed earlier is seen in detail in
Each generally cubicle paving head comprises four extensible, parallel corner struts 350, 351, 352 and 354 that extend from lower strike-offs 82 and side braces 356 and 357 upwardly to upper frame members 360, 361 and frame bars 362-365. The corner struts all have upper extensions 370 that lead to box-like roller cages 380 (
The paving heads are adjustable in length with a pair of spaced-apart, hand driven cranks. The roller cages 380 are secured to extensions 370 that have slots 371 (
Preferably the paver 50 is manually controlled by an operator (not shown) who may stand on the removable control unit 450 that can be fitted to either side of the frame 54. The control unit 450 comprises an upright ladder section 451 comprising a bottom foot stool portion 452 and an upper handrail section 454. Suitable hydraulic control circuitry 456 can be actuated by the operator with valves 458 and 459 to control paver speed. The hydraulic circuitry 456 routs fluid throughout the paver, and to its hydraulic components such as the drive motor 340, via quick-connect/disconnect fittings known in the art that are collectively designated by the reference numeral 460. The various snap-connections that engage these fittings 460 and be reconnected quickly by a workman from an opposite side of the paver 50 after the control unit 450 is mechanically moved to another side of the paver form convenience. Once the unit 450 is moved to an opposite side of the paver 50, the downwardly turned flange 461 (
From the foregoing, it will be seen that this invention is one well adapted to obtain all the ends and objects herein set forth, together with other advantages which are inherent to the structure.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations.
As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.
This utility conversion application is based upon and claims priority from prior U.S. Provisional Application entitled “Versatile Light Rail Bed Paver,” Ser. No. 62/946,140, Filed Dec. 10, 2019, by inventor Edward Andrew Waldon (American Citizen), which is hereby incorporated by reference.
Number | Date | Country | |
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62946140 | Dec 2019 | US |