US2754732A - Concrete mattress leveling and finishing machine having reciprocating screeds - Google Patents

Description

July 17, 1956 A. BEYER ,75

CONCRETE MATTRESS LEVELING AND FINISHING MACHINE HAVING RECIPROCATING SCREEDS Filed Feb. 27, 1952 :5 Sheets-Sheet 1 INVENTOR. ARNOLD BEYER July 17, 1956 A. BEYER 2,754,732

CONCRETE MATTRESS LEVELING AND FINISHING MACHINE HAVING RECIPROCATING SCREEDS Filed Feb. 27, 1952 3 Sheets-Sheet 2 M 0W? 3 y INVENTOR.

NOLD BEYER A. BEYER July CONCRETE MATTRESS LEVELING AND FINISHING MACHINE HAVING RECIPROCATING SCREEDS 3 Sheets-Sheet 3 Filed Feb. 27, 1952 m FIG. 7.

A96 A27 A a/a e 434 /2 he A86 //Z W m W /76 my ARNOLD OR.

erras United States Patent '0 CONCRETE'MATTRESS LEVELING AND FINISH- ING 'MACHINE HAVING RECIPROCATING SCREEDS Arnold Beyer, Memphis, Tenn., assignor to Weymouth Construction Company, Memphis, Tenn., 2 corporation of Wisconsin ApplicationFebruary 27, 1952, Serial No. 273,591

4 Claims. (Cl. 94-1-45.)

This invention appertainsto improvements in machines for leveling and finishing largeconcrete areas, such as floors, platforms and roadways and more particularly to an improved concrete finishing machine, designed for use in connection with the constructionof articulated concrete mattresses.

Such concrete mattresses are constructed in accordance with United States Army specificationsand are approximately four feet wide, twenty-five feet long and three inches'in thickness. The methodof construction consists of casting approximately five hundred .to seven hundred squares of mattress on the ground and then casting additional mattresses, one on top of each other, each layer of mattress being separatedby two thicknesses of kraft paper until the mattresses are cast .in stacks twelve high or over thirty-six inchesin overall height.

The primary object of this invention is to .:level and finish the top surface of the concrete mattress and,.therefore, one of the important featureslof the invention resides in the provision of a screed, which is adjustable from a height of approximately three inchesto thirty-six inches from the ground.

Another object of this invention is to provide a pair of side by side, rectilinearly out-ofephase reciprocating screeds, which are mounted on a vertically adjustable frame that is supported by a mobile carriage designed to straddle the mattresses and move longitudinally thereof so as to carry the screeds longitudinally over :the mattresses as they reciprocate transverse to the path of movement of the carriage.

A further object of this invention is to provide a screed having a resilient belting and wherein the pressure exerted against the plastic concrete is transmitted by ,the tautness of the resilient belting, which directly engages the surfaceof the mattress and produces-a dense concrete with a uniform finish. The belting is supported in a taut condition by an open arched frame that is reciprocated over the surface of the mattress.

A still further object of this invention is to provide -a pair of cooperating screeds, which are supported by a vertically adjustable frame in side by side relation and which are reciprocated in out-of-phase relation and in parallel rectilinear paths of movement by aprime mover, mounted on the supporting frame.

These and ancillary objects and structural features of merit are attained by this invention, the preferred embodiment of which is set forth in the following description and illustrated in the accompanying drawings, wherein:

, Fig. 1 is a perspective view of the concrete surface finishing and leveling machine;

Fig. 2 is a view in perspective of the vertically adjustable supporting frame and companion screeds;

:Fig. 3 is a view in perspective of one of the screeds;

Fig. 4is a transversesectional view taken on line 44 of Fig. 3;

Fig. 5 is a transverse sectional view taken on line 5-5 o sice "Fig. 6 is an enlarged detailed sectional .view taken on line 6- 6 of Fig.5;

"Fig. 7 is a top plan view of the supporting frame and screeds;

Fig. 8 is a fragmentary sectional view taken on line 8-8 of-Fig. 7, and,

Fig. '9is a View, partially in-section, of the shaft and drums for vertically adjusting the supportingframe.

Referring now more particularly to the accompanying drawings andinitially to Fig. 1 thereof, the concrete mattressfinisher 10 includes a mobile carriage 12, which has an open rectilinear main frame :14 on which a conventional internal combustion engine (not shown) is mounted. The engine 'is conventionally supported within a housing -16, which is mounted bybrackets '18 on the frame. An operators seat 20-is mounted by means of brackets 22 on the frame rearwardly of the engine housing and an axle2 i is rotatably supported'by the vertical sections of the brackets, so that the .ends extend outwardly of and above the opposing sides of the frame 14. Theaxle is rotated by the engine through a conventional transmission and differential.

Tubular legs '25 and 28am secured at their upper ends to-the opposing sides of the frame 14 adjacent the :front end thereof and carry steerable, ground engaging wheels '30 and ZZ-at their lower ends. The wheels '30and 32 are equipped'withstandard pneumatic tires and the steering is accomplished'by a standard type steering gear 34.

Standards 38 are mountedat their upper ends to the sides of the frame 14 adjacent the rear end thereof'and are rigidificd-bya transverse brace 46 and by bracing 42, The lower bifurcated ends 44 0f the standards ro'- tatably support ground engaging wheels .46, which are driven from the axle 24 by a chain drive 48. The chain 48 isentrained over a sprocket50 fixed on the extending ends of the axle 24 and overa sprocket (not shown) which is fixedly 'circumposed on the wheel axles '51. A chain tightening-sprocket 52 is carried by an arm 54 that extends forwardly from the inner branch of'the lower'bifurcated ends of the standards, the forward reach of the chain being entrainedunder and held tight 'by the idler sprocket 52.

The frame 14 is of a width slightly larger than the width of the concrete mattress, .that is, a width slightly inexcess of 'four'feet, so that rear standards 38 and the front tubular legs 26 and 28 straddle the mattress with the frame horizontally overlying and overlapping the mattress. The carriage is propelled'bythe driven wheels 46 longitudinally over the mattresses.

To effectively position the carriage and avoid damage to the sides of .the mattress, which is in a slightly plastic state, guide means or, guards are'provided and preferably include plates 56, which are elongated and transversely curved. The plates are aflixed at their concave faces 'to the inner surfaces of the tubular legs and standards and are disposed at the lower ends of the legs and standards in a manner to encompass the inner portions thereof. The plates are slightly curved around the legs and standards so as :to prevent the 'legs and standards from contactingthe opposing sides of the mattress. The plates have their curvedsurfaces confronting and engaging the sides of the mattress and the sides will, therefore, not be subjected toany-piercing or gouging force. Additionally, the plates will act as guides for .thecarriage.

.A vertically adjustable supporting frame 58 is carried by the carriage 12 and suspended from the frame -14, inwardly of the ends and sides thereof. The frame 58 :is .of rectangular shape and includes opposing channel shaped sides 60 and 62, having their open sides in confronting relation. The side channels are weldedor otherwise-secured .at their ends to end channels 64 and :66. The

corners of the frame are rigidified by triangular plates 68, which are welded or otherwise fixedly superimposed on the top of the frame at the corners.

Tubular standards or pipes are afiixed at their lower ends to the plates 68 and, thus, project upwardly from the four corners of the supporting frame 58 for engagement with the cross bars 72 and 74, which extend between the sides of the frame 14. The cross bars 72 and 74 are formed with vertical openings adjacent the sides of the frame 14. Collars 0r rings 76 are fitted in the openings to reinforce the walls thereof and the collars slidably receive the tubular standards or pipes 70.

Means is provided for raising and lowering the frame 58 by sliding the tubular standards upwardly and downwardly through the collars 76 in the cross bars. The means, shown in Figs. 1 and 9, is manually operated but power means may be provided for effecting the vertical adjustment of the frame 58. The means includes a shaft 78, which is rotatably supported by brackets 80 and 82, that are mounted on the opposing sides of the frame 14, so that the shaft underlies the housing 16. Double drums 84 and 86 are fixedly circumposed on the shaft and located on the ends thereof against movement axially of the shaft by stop collars 88.

On each of the plates 68, a sheave or pulley 90 is mounted, with the web 92 of the supporting bracket for the sheave being welded on the plates inwardly of the tubular standards 70. Cables 94 are fixed at one of their ends by nuts 96 to the cross bars, inwardly of the collars 76, and are entrained around the pulley 90 and around guide pulleys 98 carried by the sides of the frame 14. The opposing ends of the cables are suitably fixed to the drums.

As seen in Fig. 1, the cable 94 for the left rear end of the frame 58 extends under the drum 84a, while the cable 94' for frame 58 extends over the drum 84b. A similar arrangement is provided for the cables 94, that support the other corners of the frame 58, so that the shaft 78, when rotated by the crank handle 100 in a clockwise direction will wind all of the cables on the drums and correspondingly raise or lift the frame 58. counterclockwise rotation of the crank handle 100 will, of course, unwind the cables from their respective drums. A spring urged pawl and ratchet 102, as seen in Fig. 9, is provided to lock the shaft 78 against accidental rotation and prevent accidental unwinding of the cables and consequent dropping of the frame 58.

Companion screeds 104 and 106, of identical construction, are carried by the frame 58 in a suspended fashion and are reciprocated in out-of-phase relation and transversely of the path of movement of the carriage, as the carriage is moved over the mattress, to produce a rough texture finish, which is level and entirely free from humps or valleys.

The screed 104, as seen in Figs. 3-6, includes an arched rectangular frame 108 having opposing sides 110 and 112. The sides are formed with flat center sections 114, and declined end sections 116 and 118. The end sections 118 of each side of the frame are connected by an integral end bar 120, which is arranged transverse thereto.

The other end of the frame is open and is provided with a cross bar 122, which has a pair of rearwardly directed and longitudinally spaced arms 124 and 126. The arms are apertured to receive a rod 128 that extends transversely between the free ends of the declined end sections 116 of each side of the frame. The rod is formed with integral stops 127 that locate the arms thereon.

The declined end sections 116 of each of the sides 110 and 112 of the frame are formed with upstanding apertured ears 130 and 132 that are arranged in confronting relation to upstanding ears 134 and 136 formed vertically on the ends of the end bar 122. Elongated bolts 138 are disposed through the apertures in the confronting ears 130 and 136 and the ears 132 and 134 to adjustably fix 4 the end of the frame to the end bar 122, for a purpose to be described.

An elongated rectangular shaped resilient belting 140 is carried by the ends of the frame and is secured thereto in taut condition. One end of the belting is secured to the end bar 120 of the frame by a clamping plate 142, which is secured by bolts 144 to the end bar 120, with the end of the belting clamped between the plate and the end bar. The other end of the belting is secured to the end bar 122 by a similar clamping plate 146 and bolts 148, that pass through the plate and belting. The bolts 138 are provided to take up any slack in the belting, since as the bolts are drawn up tighter, the end bar 122 can swing upwardly about the rod 128 to thereby tighten the belting 140.

A flat reinforcing plate 150 is superimposed on the upper surface of the belting 140 and is preferably of sheet metal or the like material. As seen in Fig. 5, the plate 150 is formed on its outer side edge with an angular upstanding fiange 152 and the outer side edge 154 of the belting is turned up and secured by bolts 156 to the flange. The bolts 156 constitute the sole fastening means for securing the reinforcing sheet 150 on the resilient belting so that the rest of the sheet merely lies on the belting and serves to weight the belting.

The screed 106 is constructed in a manner similar to the construction of the screed 104, except that, as seen in Fig. 7, the reinforcing sheet 158 is attached to the end bar 122' by a chain or similar connecting member 160, that is secured to the end of the sheet and to the center bolt assembly 156. Similarly, the other end of the sheet is secured by a chain to the bolt 144'. Thus, the sides and ends of the sheet 158 are not attached to the resilient belting but are attached to the ends of the frame, so that the sheet 158 rests on the upper surface of the resilient belting 140', without any attachment to the belting.

As seen in Fig. 7, the inner side edge of the belting 140 on the screed 104 is overlapped by the inner side edge of the belting 140 on the screed 106, so that the inner side edge of the belting 140' rides over the adjacent side edge of the belting 140, as the screeds are reciprocated in opposite directions. The inner side edges of the reinforcing plates or sheets 150 or 158 are spaced from the inner side edges of the respective beltings, so that the inner side edges of the belting are not reinforced and are unattached.

As seen in Figs. 2 and 8, guide means is provided for each of the screeds. The guide means includes a pair of vertically arranged plates 162 and 164, which are arranged in pairs between the opposing sides 60 and 62 of the frame 58. As seen in Fig. 8, the inner confronting faces of the plates are formed with vertically spaced bars and 172 that extend laterally from each plate and form tracks within which the opposing side edges of the plate 174 are slidably disposed. The plate 174 is mounted on the ends of the upstanding legs of a channel bar 176, which is supported by a pair of cross bars 178 and 180. The cross bars are transversely mounted between the center sections 112 on each side of the screed frames.

Upstanding complementary apertured ears 182 are formed on the upper surface of the plate 174 for the screed 106 and a similar pair of ears 184 are formed on the upper surface of the plate 174' for the screed 104. A connecting rod 186 is secured by a wrist pin 188 to the ears 182 and connects the plate 174 to the throw 190 of a crank shaft 192. A connecting rod 194 is fixed to the ears 184 by pin 196 and connects the plate 174' to the throw 198 of the crank shaft. The ends of the crank shaft are journaled in the bearing blocks 200, which are mounted on cross bars 202 that extend between the sides 60 and 62 of the frame 58. Intermediate the ends thereof, the shaft is supported by hearing brackets 204, which extend upwardly from the plates 162 and 164.

A sprocket 206 is fixed on one end of the crank shaft and is connected by a suitable belt and chain transmission W a c nventional gasoline engine 208, which is mounted on one end of the frame 58. The chain 206 is driven by the engine through a belt drive 210 and gear reduction unit 212, which drives a sprocket 214. The sprockets 206 and 214 are connected by a chain 216, which is provided with a chain tightening sprocket 218, that is mounted on a vertically slotted bracket 220, so that the sprocket 218 can be adjusted vertically with respect to the upper reach of the chain on which it engages.

In operation, the carriage is guided by an operator through the medium of the front steerable wheels 30 and 32 from the seat 20 and is propelled by the engine driven axle 24 and chain drive therefrom to the rear driven wheels 46. The front tubular legs 26 and 28 and the rear standards 38 are spaced apart to straddle a row of mattress, so that the frame 12 horizontally overlies the mattress.

Conventionally, approximately 500 to 700 squares of mattress are cast on the ground, in rows of various lengths. The carriage straddles the rows and moves longitudinally over the mattress, which are in plastic state.

Each mattress has a width of 4 feet, a length of 25 feet and a depth of 3 inches. The mattresses after curing are subsequently shipped to predetermined destinations for use for example by the Air Force for reinforcement installation of emergency landing strips. The mattresses are placed upon sandy or soft ground and a landing strip or mat is placed thereover.

The gasoline engine 208 is connected to the belt drive 210 by a clutch (not shown) actuated by a clutch handle 222. Before the operator assumes his position on the seat 20 and operates the carriage in a manner similar to the operation of a tractor or other vehicle, the clutch is engaged through the medium of a handle 222 so that the screed frames are reciprocated by the engine 208.

It will be noted that the engine 208 is disposed at the front end 66 of the frame 58 so that the front of the carriage is weighted in order to counteract the weight of the engine and operator at the rear of the frame 12. The frame 58 is adjusted by using the crank 100 and through the medium of the pulleys and cable system, so that the under surfaces of the beltings 140 and 140' are in direct engagement or contact with the upper surfaces of the freshly poured concrete mattress, as the carriage is driven longitudinally over the mattress. The screeds are reciprocated transversely of the path of movement of the carriage or transversely of the longitudinal axis of the mattress in a sawing action or out-of-phase rectilinear paths of movement. The flange 152 and outer side edge 154 of the belting 140 form the lead edge, as the carriage is driven over the mattress. Thus, as seen in Fig. 1, the lead edge of the first screed 104 is upturned so that it rides over and smooths down the plastic concrete forming the upper surface of the engaged mattress. This prevents any gouging of the surface.

The first screed 104 has its reinforcing plate 150 secured to the lead edge 154 thereof, so that the reinforcing plate weights the lead edge and rests on the belting in a somewhat overall secured manner.

The belting 140 on the lead or first screed 104 is therefore weighted more than the belting 140 on the trailing or second screed 106. The reinforcing plate or sheet 158 on the belting 140 of the trailing screed 106 floats on the belting, since it is not secured to the belting but is secured at its ends to the ends of the frame for the trailing screed 106.

Thus, the lead screed 104 packs down, due to its weight, the surface of the mattress, as it is moved longitudinally over the surface and reciprocated transversely thereof. The belting 140' on the trailing screed is held in taut condition and the reinforcing plate floats thereon so that the pressure that the belting 140' exerts against the fresh concrete is transmitted by the tautness of the rubber belting and not through any direct pressure by the reinforcing plate on any of the parts of the frame which support the belting.

The reciprocating screeds, by the rectilinear or sawing and screeding action, produce final consolidation of the concrete and the final finishing. The end result is a dense concrete, packed by the lead screed 104 and initially smoothed thereby and finally smoothed or leveled by the trailing screed 106. The finish is a rough texture, rather than a smooth or glassy finish, and is perfect in alignment and entirely free of humps or valleys.

After the first row of mattress has been finished, a double layer of kraft paper is laid on the finished upper surface and an additional mattress is cast on top of the kraft paper. The frame 58 is then raised a distance of approximately three inches, so that the engaging or under surfaces of the belting and 140' are positioned for direct and proper contact with the plastic upper surface of the freshly poured second layer of concrete mattress.

The operation is continued, with the frame 58 being raised, as additional layers of mattress are cast, until the mattresses are cast in layers or stacks approximately twelve high.

While a specific form of drive means for the carriage and specific type of prime mover and operating means for the screed frames has been shown in the disclosed and preferred embodiment, it is understood that changes can be made in these details, as well as in other parts of the disclosed embodiment, so that limitation is sought only in accordance with the appended claims.

Having thus described this invention, what is claimed 1s:

1. A machine for the finishing of concrete mattresses laid in successive vertical tiers comprising a rectangular mobile frame, vertical legs supporting the four corners of the mobile frame, wheels supporting said legs, means for driving at least two of said wheels for propelling said mobile frame at a uniform rate of speed over the tiers of mattresses, a support sub-frame adjustably supported below said mobile frame, a pair of transverse screed mem' bers carried by said support frame, means for reciprocating said screed members in opposed directions, means to elevate said sub-frame for vertical adjustment whereby the screeds can be reciprocated at seelcted levels whereby successive vertical tiers of mattresses can be finished as the machine is passed longitudinally thereover.

2. A machine for successively finishing concrete mattresses individually as the mattresses are laid in vertical stacks as claimed in claim 1 wherein said elevating means for said support means comprises hoist means carried by said mobile frame one element of which is connected to said support means for raising and lowering said support means within said mobile frame.

3. A machine for successively finishing concrete mattresses individually as the mattresses are laid in vertical stacks as claimed in claim 2 further comprising guide means one end of which is carried by said support means and the other end of which passes through a portion of said mobile frame for guiding said support and its reciiprocating screeds for varying positions of said screeds as the stack of mattresses becomes successively higher.

4. A machine for successively finishing concrete mattresses individually as the mattresses are laid in vertical stacks as claimed in claim 1 wherein said support means comprises a vertically movable platform supporting thereon drive means for reciprocating said screeds carried by said platform.

References Cited in the file of this patent UNITED STATES PATENTS 1,271,947 Ross July 9, 1918 1,832,951 Thorson Nov. 24, 1931 1,978,773 Trant Oct. 30, 1934 2,054,263 McCrery Sept. 15, 1936 2,192,027 Crowder Feb. 27, 1940 2,529,749 Wade et al. Nov. 14, 1950 OTHER REFERENCES Engineering News Record, Oct. 9, 1919, page 712.

Images