US 3412658 A
Description (OCR text may contain errors)
Nov. 26, 1968 .1. E. GRIFFIN 3,412,658
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United States Patent O 3,412,658 ROAD SURFACING DEVICE John E. Griln, 22S N. Lucas St., Iowa City, Iowa 52240 Filed Nov. 14, 1966, Ser. No. 594,020 4 Claims. (Cl. 94-45) ABSTRACT OF THE DISCLOSURE A power float having a screed frame resta-ble directly upon a pair of screeds with attachment structure for attaching the frame to the screeds without forming any openings in the screeds and with power structure for automatically moving the oat along a surface including a power driven Winch with cable means wound around the winch in opposite directions and with the free ends of the cable being attached at a remote location.
This invention is concerned with a road surfacing device useful in preparing poured concrete surfaces such as roads, driveways, alleys and the like. It is specifically directed to a new, lightweight, portable power driven float which allows a large volume of concrete to be surfaced in a short period of time. It replaces large, expensive pieces of heavy equipment heretofore used which are diiiicult to use and costly to repair.
In its more specific embodiments, the power float of this invention comprises a screed frame adapted to hold a pair of screeds, novel adjustable shaft driven vibrator means and utilizes, in a preferred embodiment, a commercially available gasoline powered engine of the type commonly found on power lawn mowers.
A particularly outstanding embodiment utilizes a winch and cable arrangement for allowing the device to -be selfpropelled, thus making it very useful in striking olf large concrete surfaces such as roadways.
As indicated, the invention is directed to a simple, yet unique power oat. A review of the prior art indicates that when attempts have been made to mechanically oat and shape concrete, the results are manifested by large, heavy and often cumbersome pieces of equipment that are exceedingly expensive. Since the pouring of concrete roadways is often seasonal, breakdowns are costly in time and labor to contractors attempting to meet job schedules. Also, in the case of small contractors, they are often unable to afford these large items of concrete finishing equipment even on a rental basis.
The present invention lls a long-felt need in the road surfacing art. It provides a simple, lightweight and compact power float that is inexpensive, may be operated by one man and is sufficiently portable so that it may be trucked from job to job in small trucks or even in the back of a standard size station wagon.
The power oat of the invention is also capable of ready adaptation to a variety of road surfacing jobs such as crowning, curb forming and the like, without necessitating expensive modifications. It therefore becomes an object of the invention to provide an improved, lightweight, portable inexpensive power oat.
Summary Another object of the invention is to provide a power oat adaptable to a wide variety of concrete pouring situations.
3,412,658 Patented Nov. 26, 1968 ICC A further object of the invention is to furnish a simple power oat which by suitable modification can be made self-propelled.
Other objects will appear hereinafter.
For a more comprehensive understanding of the invention, reference may be had to the drawing of which:
FIG. l is a plan view of the power float of the invention.
FIG. 2 is a side View of a screed mounting clamp and is taken across lines 2 2 of FIG. 1.
FIG. 3 is a front view, broken away in part, showing the novel shaft driven adjustable vibration means.
FIG. 4 is a side view taken across lines 4 4 of FIG. 3.
FIG. 5 is a top view showing the self-propelled adaptation of the invention.
FIG. 6 is a front View corresponding to FIG. 5.
With specific reference to the drawings, and in particular FIG. 1, there is shown a screed frame 10 comprising a pair of parallel spaced-apart plates 12 and 14 respectively. The plates are formed from conventional angle iron so as to have a top portion 16 into which screeds 18 and 20 lit. To hold the screeds in position, there are provided screed clamps 22 which are shown to best advantage in FIG. 2. As can be seen, the back end of the screed clamp has aflixed thereto a spacing bar 24 which acts to properly position the clamp with respect to the top portion 16 of the screed plate. Drilled into the screed clamp is a hole for accommodating bolt 26 which extends through mounting bracket 28 with the total assembly providing a secure, yet easily removable, fastening for the screeds 18 and 20. To hold the screed plates in spaced-apart parallel relationship, spacer bars 30 are provided. This furnishes a screed frame assembly which gives lirm support and rigidity t0 the screeds when mounted therein. It should be observed that mounting brackets 28 are fastened to the sides of the spacer bars 30.
Positioned at opposite ends of the screed frame assembly are a pair of semi-circular handle mounting brackets 32 and 34. Fitted to the handle mounting brackets is U- shaped handle 36 which is provided with slotted ends 38 which fit in loose relationship to the handle mounting brackets and are attached thereto by mounting bolts 40. It is obvious that the handle is movable in an arcuate fashion and allows the operator of the device freedom in directing its forward and backward movements.
Positioned on top of the screed frame assembly is a motor mount housing 42. This housing, as can be seen in FIGS. 1 and 3, is la box-like structure having la bottom portion 44 and ya deck 46. The bottom portion contains a pair of parallel angle iron plates 48 which are adapted by means of a slot (not shown) to receive pulley 50 and shaft 52. The pulley is connected to shaft 52 which is journaled in pillow blocks 54 and 56.
Positioned at about the center of the shaft, in a preferred embodiment of the invention, are a pair of pieshaped balance weights 58 and 60. As can be seen to best advantage in FIG. 4, the apex of the pie-shaped balance weights are bored to receive the shaft 52 and are side tapped to receive adjustment screws 62 and 64.
By adjusting the pie-shaped balance weights around the shaft, the vibrational characteristics of the screed frame and the screeds attached thereto m-ay be easily regulated to provide optimum effectiveness for surfacing any particular area of concrete to be operated upon by the device. The setting shown in FIG. 4 provides minimum vibration whereas when the pie-shaped segments rare in parallel relationship to each other maximum vibration is achieved.
To power the device, :pulley 50 is driven by means of belt 66 which is attached to a conventional gasolinedriven engine or motor 68. The motor may be a gasoline engine of the type used to power small domestic devices such as power lawn mowers, rototillers and the like. Experience has shown that a 21/4 horsepower motor delivers more than enough power to drive pulley 70 which is attached to the motor shaft, to satisfactorily operate the screed.
To actuate the power float, the operator starts motor 63 and, after having 4ascertained that the proper screeds are in the screed frame, by a simple pulling motion can rapidly float large areas in a relatively short period of time. For instance, under actual operating conditions, it is possible to lioat more than several hundred linear feet of a conventional ten-foot driveway in but a few hours.
While the device illustrated in FIGS. 1 through 4 is adequate for surfacing small areas poured in concrete, the invention is capable of further modifications to allow the power floating of large `concrete areas such as highways by means of the adaptations shown in FIGS. and 6. With particular reference to these drawings, there is shown what may be termed a self-propelled power float. The basic construction details are similar to those previously discussed with the exception that the shaft 52 is longer and is fitted with a power take-off pulley 72. This pulley through belt 74 and pulley 76 is used to power a speed reducing gear box 78. To this speed reducer through clutch 80 is affixed winch 82.
The winch being driven at a substantially slower speed than the shaft 52 affords a take-up mechanism for cable 84. Cable 84 is so wound .around winch 82 that the opposite ends of the cable 86 and 88 are taken up in opposite directions to each other as wound on the winch.
As shown in FIG. 5, the screeds 18 and 20' are maintained parallel at their ends by means of cross-braces 86 and 88, respectively. Fitted within the front end of screed 18 is horizontally-positioned pulleys 90 and 92, which .are adapted to receive the ends of the cable S6 and 88. After passing through the horizontally-disposed guide pulleys 90 and 92, the ends of the cable may be attached to suitable stakes or deadmen 94 and 96.
For purposes of illustrating the adaptability and versatility of the device, the self-propelled oat has its one end fitted with curb-forming plates 98 and 99 which are fitted in mirror image to opposite ends of the screeds 18 and 20. Fitted between the plates is a feed hopper 100 into which concrete may be poured for purposes of -adding additional concrete during the curb-forming operations.
As the winch 82 begins to turn, tension is applied to each end of the cable and the entire power float is moved along the area to be struck of nished. By selecting a suitable speed reducing mechanism 7S, the rate of travel of the entire apparatus may be carefully controlled.
An important feature of the invention resides in the fact that the screeds 18 and 20 :are most suitably formed of an inexpensive easily replaceable material such as wood. Since they are readily removed and attached to the screed frame 10, it is obvious that a variety of screed shapes can be carried to a job site and installed into the screed frame. This enables the device to perform functions only heretofore capable of being performed by complex expensive heavy mechanical equipment. As the screeds lose their cont-our, they may be discarded and rcplaced with fresh screeds. The invention, while of simple design, is extremely versatile in that a variety of adjustments can be made to adapt it to an infinite number of paving situations.
In certain instances, it has been found desirable to arrange two of the devices in tandem on a single pair of screeds to permit more rapid striking of large concrete surfaces. The invention, as indicated, provides ia small portable unit that can be easily transported from job to job in simple vehicular conveyances.
Having thus described my invention, it is claimed 1. A power float for surfacing concrete roadways, driveways and the like, comprising a screed frame a-dapted to hold a pair of screeds in parallel spaced-apart relationship, a pair of screeds mounted on said screed frame, vibrator means for said screed frame, said vibrator means comprising a shaft `having an adjustable balance weight positioned thereon capable of imparting vibrational imbalance to said shaft under conditions of high speed rotation, vmotor means for ydriving said shaft, a winch, a cable passing about the winch intermediate the ends of the cable to have both ends of the cabie free for connection away from the frame and provide take-up in opposite directions for each end of the cable, and guide vmeans for guiding the cable in a predetermined direction comprising at least two pulleys located one at each end of the frame to engage the cable and guide the frame during its entire movement.
2. A power iioat forsurfacing concrete roadways, driveways and the like, comprising a screed -frame adapted to hold a pair of screeds in parallel spaced-apart relationship, a pair of screeds mounted on said screed frame, vibrator means for said screed frame, said vibrator means comprising la shaft having an adjustable balance weight positioned thereon capable of imparting vibrational irnbalance to said shaft under conditions of high speed rotation, 'motor means for driving said shaft, the screed frame comprising a pair of lrigid parallel spaced apart plates having associated therewith adjustable clamp means for engaging the pair of screeds, each of said plates being generally horizontal and defined by an angle iron section with the other section of the angle iron forming a depending flange whereby a corner is defined to receive a corner of a screed, and said clamp means for each screed includes an angle iron having one fiange engageable with one of said plates, and a removable fastener extending through both angle irons to hold the angle irons and screed in assembled relation.
3. A power float for surfacing concrete surfaces, comprising a screed frame adapted to hold a pair of screeds in parallel spaced apart relation, a pair of removable screeds mounted on said screed frame, vibrator means operatively connected to said screed frame, power means for driving said vibrator means, a winch operatively connected to said power means, said winch being positioned intermediate the outer ends of the frame and having its rotational axis generally parallel to the path of travel of the iioat, cable means passed around said winch intermediate the ends of the cable means to have both ends of the cable means free for connection away from the frame, said cable means being wound around said winch to provide take-up in opposite directions for each free end of the cable means as said winch rotates, and guide means for the free ends of said cable means at each of said outer ends of said frame to guide the ends of said cable means from said winch along a direction normal to said screeds.
4. A power float for surfacing concrete roadways, driveways and the like, comprising a screed frame adapted to hold a pair of screeds in parallel spaced-apart relationship, a pair of screeds mounted on said screed frame, vibrator means for said screed frame, said vibrator means comprising a shaft having an adjustable balance weight positioned thereon capable of imparting vibrational imbalance to said shaft under conditions of high speed rotation, motor means for driving said shaft, the screed frame comprising a pair of rigid parallel spaced apart plates having associated therewith adjustable clamp means for engaging the pair of screeds, each of said plates being generally horizontal and defined by an angle iron section with the other section of the angle iron forming a depending tiange whereby a corner is defined to receive a corner of a screed and support the weight of the screed frame thereon, and said clamp means for each screed includes a clamp member engageable with one References Cited UNITED STATES PATENTS 6/ 1935 Mandt 94--44 12/ 1938 Jackson 94-48 1/1940 Heltzel 94-45 Oswald 94-45 Whiteman 94-45 Troxell 94-45 Wells 94--48 Nave 94-48 Peterson 94--48 X Maginniss 94-48 NILE C. BYERS, IR., Primary Examiner.