US 3294001 A
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Description (OCR text may contain errors)
ec, 2 39% J. E. THOMSON 3,
CONCRETE SPREADING AND FINISHING MACHINE Filed June 29, 1964 4 SheetsSheet 1 I NVEN TOR.
JOHN E. THOMSON ATTORNEYS Dec. 2?, 19% J. E. THOMSON 329mm CONCRETE SPREADING AND FINISHING MACHINE Filed June 29, 1964 4 Sheets-Sheet 2 INVENTOR.
. THOMSON fW W ?, 11966 J. E. THOMSON M M CONCRETE SPREADING AND FINISHING MACHINE Filed June 29, 1964 4 Sheets-Sheet INVENTOR. JON/V E THOMSON ATTORNEYS ec, 27, 1966 J. E. THOMSON CONCRETE SPREADING AND FINISHING MACHINE Filed June 29, 1964 4 Sheets-Sheet 4 75; INVENTOR. L 3 JOHN E. THOMSON BY United States Patent Iowa Filed June 29, 1964, Ser. No. 378,607 3 Claims. (Cl. 94-45) The present invention relates to machines used in the construction of concrete roads and particularly to improvements in machines employed for spreading and finishing of the concrete used in such roads.
Conventional machines for finishing roads comprise screeds or finishing blades which span the forms between which the concrete of the road is poured. These screeds are supported on a truss which is in turn supported on wheeled trucks which run on tracks at opposite sides of the forms. Many machines have spreading devices which move in front of the screed for reducing or leveling piles of concrete which has been dumped by trucks or large buckets. Also the screeds of most machines are adjustable so that they may be curved to form an arched surface or crown on the road.
It is an object of the present invention to provide an improved spreading device for concrete spreading and finishing machines capable of imparting a smoothing or troweling effect to the concrete.
Another object is to provide means for guiding such a spreading device, as it is driven from side to side of the road, in an upwardly curved path following the crown of the road being formed.
Another object is to provide driving means which normally moves the spreader across the road and automatically reverses this movement at the end of each cycle or crossing and to provide control means with which an operator can interrupt the usual driving cycle and cause the spreader to undertake short strokes.
A further object is to provide a vibrator in combination with a spreader to facilitate spreading and to compact the pour as it is being finished in order to prevent surface slumping which often occurs prior to setting of the plastic mass.
Further and more specific objects and advantages of the invention and the manner in which it is carried into practice will be made apparent in the following specification wherein reference is made to the accompanying drawings illustratng a preferred form of the invention.
In the drawings:
FIG. 1 is a view in front elevation of a concrete spreading and finishing machine embodying the present invention;
FIG. 2 is an enlarged sectional view taken on the line 11-11 of FIG. 1;
FIG. 3 is a sectional view taken on the line III-III of FIG. 1 showing the carriage for the spreader mechanism but with a vibrator shown in FIG. 1 removed;
FIG. 4 is a view in front elevation of the carriage shown in FIG. 3;
FIG. 5 is a perspective detail showing the spreader member and a portion of a vibrator which is associated therewith; and
FIG. 6 is a schematic diagram illustrating electric circuits.
Referring first to FIG. 1 of the drawings, a concrete spreading and finishing machine embodying the present invention is illustrated with the driving means, controls therefor and other details which do not affect the present invention omitted. Generally speaking, the machine comprises screeds, one of which is shown at 10 in FIG. 1, the other screed being shown at 11 in FIG. 2 lies directly behind the screed 10. These screeds are supported by 3,294,001 Patented Dec. 27, 1966 "ice vertically adjustable jacks 12 fixed at spaced intervals to the main body or truss 14 of the machine which is in turn supported through wheeled trucks, generally indicated at 15, riding on tracks 16 disposed at opposite sides of the road.
The screeds 10 and 11 are supported by more or less conventional means to enable them to be arched or crowned and to be oscillated in the direction of their length to produce a smoothing or finishing effect. The support means are shown in FIG. 2 as including jack screws 12 which have hand wheels 16 controlling a threaded member 17 which raises and lowers a tube 18 supporting a block 19 having rollers 20 thereon. Each pair of rollers supports a short channel-shaped housing 22 (see also FIG. 1) to which the screeds 10 and 11 are connected as by bolts 23. Adjustment of the jack screws to different heights enables the screeds to be curved to conform to the desired surface of the road to be finished. A reciprocating action is imparted to the screeds by an eccentric drive 25 (see FIG. 1) and rods 24 connecting the drive to the screeds. The driving motor for the eccentric which is not herein illustrated may be hydraulic.
Since concrete in its plastic form is usually dumped in irregular piles in advance of the finishing machine as it moves along its tracks 16, a spreading device moving forwardly of the screeds is desirable for distributing these piles. The spreading device of the present machine is shown at 26 in FIGS. 1, 3, 4 and 5 as supported by a carriage 27 which rides on rails 28 and 29 extending throughout the full width of the machine in front of the truss 14. These rails, which are of channel-shaped cross section, are sufi'iciently flexible to assume the same curve assumed by the screeds to follow the crown of the road. Consequently the spreader 26 in its travel from side to side will spread and strike off the concrete in the same manner and to the same contour at which the final finish is applied. To accomplish this curving of the rails, they are mounted in the manner shown in FIG. 2 on spaced brackets, one of which is shown at 31, there being one such bracket for each pair of jack screws 12. Each bracket 31 is carried at the end of a beam 32 which is secured as by bolts 33 to the blocks 19 which are raised and lowered as the curve is imparted to the screeds 10 and 11.
The carriage 27, as shown in FIGS. 3 and 4, has upper rollers 35 and lower rollers 36 which fit within the channelshaped rails 28 and 29, upper rollers 37 and 38 embracing both sides of the upper rail and lower rollers 39 which bear against the forward edge of the lower rail.
To drive the carriage from end to end of the rails, a hydraulic motor shown at 40 in FIG. 4 drives a chain 41 which in turn drives a sprocket 42. Sprocket 42 is mounted on the same shaft as a sprocket 43 shown in FIG. 3. The sprocket 43 meshes with a chain 44 (see FIGS. 1 and 4) which extends throughout the full length of the rails and is anchored at both ends as by threaded adjusting members 45. This chain is trained over two idlers, best shown in dotted lines at 46 and 47 in FIG. 4, and around the sprocket 43 so that the sprocket travels the length of the chain taking the carriage with it. The spreader 26 is mounted on a vertically disposed telescoping shaft 50 which can be raised and lowered by means of a hydraulic jack 51 mounted directly above it. It may also be angularly adjusted between the two positions best shown in FIG. 6 so that either of its diverging arms which form a V can alternately lie parallel to the screed 10. The full line position in FIG. 6 represents the position occupied by the spreader during leftward movement and the dotted line position is for rightward movement. Adjustment from one position to the other is accomplished by a double acting hydraulic jack,
best shown at 52 in FIG. 4, the rod of which, shown at 53 in FIG. 6, is connected to a crank arm 54 at the upper end of the telescoping shaft 50 which supports the spreader. The hydraulic circuits to the jacks and motors herein referred to are not shown since they are conventional but the hydraulic elements carried on the carriage 27 are served by flexible hoses 56 suspended from a rotatable boom 57 which is balanced by springs 58 and permits the carriage 27 to travel from end to end of the machine.
In normal operation, the carriage constantly moves between the two ends of the machine and when it reaches either end, the position of the spreader 26 is reversed and it starts to travel toward the other end. However in the event that a large quantity of concrete is encountered or for any other reason the operator feels that the spreader should be manipulated from side to side in shorter strokes, this can be accomplished by a hand control at a control panel positioned as at 60 in FIG. 1. The automatic and manual control of the carriage and spreader are both accomplished by solenoid actuated valves for directing fluid to the jack and motor as illustrated in the circuit diagram of FIG. 6. In this figure power from a source such as battery 62, passes through a main control switch S1 and a normally closed limit switch LS2 and switch S4 to energize a solenoid 63 on the valve 64 for directing hydraulic fluid to the motor 40 for driving the sprocket 42 of FIG. 4 in one direction. The direction is toward the left as shown in FIG. 6. The limit switch LS-2 is mounted at the left end of the rails as viewed in FIG. 1 and is engaged by the carriage 27 so that it is moved to break the circuit to the valve 64 of motor 40 and, since this valve is of the spring centered type, the motor will stop. This same movement of the switch LS-2 closes the circuit to a solenoid 66 of a valve 67 which controls flow to opposite ends of the jack 52. Momentary closing of this circuit actuates the jack to move the spreader 26 from the full line position to the dotted line position which it assumes during rightward travel. The crank arm 54 of the spreader is mechanically linked, as indicated by the broken line 68, with the valves S 1 and S so that reversal of the position of the spreader opens valve S-4 and closes valve S5 to energize solenoid 69 of valve 64 and drive motor 40 in the opposite direction. At the end of its rightward travel -the carriage engages and opens limit switch 3 closing the circuit to solenoid 70 of valve 67 and again reversing the position of jacks 52 and the spreader which serves again to reverse the drive of the motor 40. The operator is enabled to override the automatic cycle hereinabove described by a normally open switch 72 on the control panel 60. This switch can be closed to complete the circuit to either of the solenoids 66 or 70 for reversing the position of the spreader which in turn actuates switches S4 and S5 to reverse the direction of drive of the motor. In this manner, the spreader can be manipulated to work down or gradually diminish a large pile of concrete.
Compaction of newly poured concrete is often accomplished with a vibrator in the form of a steel bar having an internal electrically or hydraulically driven eccentric or other vibrating mechanism so that upon being inserted into the plastic concrete, it imparts shock or vibratory motion thereto which causes rapid settling and compaction. Such a compactor is shown at 75 in FIG. 1 as supported by a bracket 76 extending forwardly from the carriage 27 so that it will occupy a position in front of the spreader as shown in FIG. 5 where it penetrates the concrete to agitate and compact it prior to the action of the spreader itself.
What is claimed is:
1. In a concrete spreading and finishing machine having means for moving it longitudinally of a road to be paved, a pair of spaced screed supports, jack means for vertically adjusting said screed supports to determine crown, a screed supported by each screed support for reciprocable movement, means for reciprocating said screeds relative to their supports, spaced beams connected to the lower portions of said jacks and extending forwardly, track means supported by said beams and responsive to crown adjustment of said screed supports, and a spreader member supported by said track for lateral movement ahead of said reciprocating screeds, whereby the spreader will follow a curved path corresponding to the curvature of the screeds.
2. In a concrete spreading and finishing machine having means for moving it longitudinally of a road to be paved, a pair of spaced screed supports, separate jack means secured to each of said screed supports for vertically adjusting said screed supports to determine crown, a screed supported by each screed support for reciprocable movement, means for reciprocating said screeds relative to their supports, spaced beams extending transversely of said screeds and connected to said screed supports and extending forwardly of said screeds, track means supported by said beams and responsive to crown adjustment of said screed supports, and a spreader member supported by said track for lateral movement ahead of said reciprocating screeds, whereby the spreader will follow a curved path corresponding to the curvature of the screeds.
3. In a concrete spreading and finishing machine for paving a roadway, a spreader member with connected first and second arms diverging forwardly and having separate flat bottom surfaces on a common plane with a front upright wall and with an intermediate open area, means supporting said member and moving it transversely with respect to the direction of movement of the machine, with the first arm extending in the direction of said movement and the second arm forming an obtuse angle therewith and extending outwardly therefrom to spread the concrete laterally, means angularly rotating and reversing the direction of lateral movement of said spreader member at each lateral extremity of said roadway whereby said second arm extends in the direction of said lateral movement and said first arm acts as the spreader.
References Cited by the Examiner UNITED STATES PATENTS 2,032,205 2/1936 Gage 9445 2,097,913 11/1937 Clifford 9444 2,244,297 6/1941 Heltzel 9445 2,334,717 11/1943 Long 9445 2,358,085 9/1944 Millikin 9445 2,382,096 8/1945 Pierce 9445 2,43 8,159 3/1948 Faber 9445 3,439,620 4/1948 Faber 9444 2,603,132 7/ 1952 Miller 9445 2,957,396 10/1960 Bederman 9445 3,137,219 6/1964 Hudis 9445 3,208,361 9/1965 Bidwell 9445 JACOB L. NACKENQFF, Primary Examiner.