US2382096A - Paving machine - Google Patents

Description

Aug. 14,- 1945.

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Ga r/es fi-r g Arm/swan Patented Aug. 14, 1945 PAVING MACHINE Charles W. Pierce, La Cresoenta, Calif., assignor to Viber Company, a corporation of, California Application February 14, 1944, Serial N0.'522,301

10 Claims.

This invention relates to paving machines; and in particular to a machine for compacting concrete by internal vibration.

One objectof my invention is to provide a machine for the placement of concrete in pavements, slabs and the likewhich is of large capacity and highly efficient in compacting concrete of large sized aggregates and of low water content. Another object is to provide a machine for leveling, compacting and finishing a concrete slab from a mass of concrete upon a roadway.

Another object is to provide a machine which vibrates the concrete in place on a roadbed.

Another object is to provide a machine which vibrates plastic material such as concrete on a roadbed between crosswise expansion joints, with means for raising and lowering'the vibrating mechanism over the crosswise joint members.

Still another object is to provide a mechanism for raising and lowering .a gang of vibratory units to avoid crosswise joint members in the roadway. v

A further object is to provide means for holding a gang of tubular vibrators in inclined partly submerged operative position while moving the vibrators through the concrete to compactit,

Another object is to provide a paving machine which will place concrete masses which are too harsh and dry to be properly placed on a roadbed v by any other known means.

These and other objects will be apparent from the following description and the drawings in which:

Fig. 1 is a plan view showing one form of my paving machine;

Fig. 2 is a side elevation view of the same;

Fig. 3 is a cross-sectional view taken on the line 33, the vibrators being omitted for clarity;

Fig. 4' is a cross-sectiona1 view taken on the line 4-4 of Fig. 3; f i

Fig. 5 is a detail showing the piping connections for the control valves to the hydraulic lines;

Fig. 6 is a perspective view showing the supporting structure for individual vibrator units;

Fig. '7 is an elevation view partly in section showing one of the individual vibrators Fig. 8 is a cross-sectional view showingthe details of the telescopic arms of the lever'mecha nism;

Fig. 8a Fig. 8;

Fig. 9 is a cross-sectional view taken on the line 9-9 of Fig. 8;

Fig. 10 is a cross-sectional view taken on the line Ill-l0 of Fig. 8;

is a top view of the telescopic arm of Figfll is a detail showing the end fastening member of the lever arm of Fig. 8;

Fig. 12 is an enlarged side elevation of the telescopic lever arrangement;

Fig. 13 is an end elevation of the same;

Fig. 14 is a plan view of the same;

Fig. 15 is an enlarged side elevation of an alternative lever arrangement for elevating the vibrators;

Fig. 16 is 'a front elevation of the same;

Fig. 17 is a plan view of the same;

Fig. 18 is an enlarged side elevation of another alternative lever arrangement for elevating the vibrators; v

Fig. 19 is a plan view of the same.

In general, my paving machine consists of a carriage adapted to travel along the strip to be paved, and carrying a power unit, an electrical generator, an hydraulic liquid pressure system,

a gang of insertible vibrator units, a cross-thestrip oscillating screed member, and means to insert the vibrators in inclined position to oper ate beneath the screed member in the concrete, together with means to raise and lower the vibrators to avoid expansion joint rrfembers in the paving strip,

My paving or concrete placing machine in its preferred form is shown in Figs. 1 to 14 inclu- 'sive, and consists of a carriage having side members II and I2 and frame cross members l4, l5, l5, I8, l1, and !8, with flanged wheels I9, 20, 2| and 22 mounted on individual stub shafts in outer bearings 23, 24; 25 and 26 attached to the main frameside members 'H and I2 by brackets 21, 28, 29 and 3B; and in rear inner bearings 32 and 33 attached to longitudinal frame members 35 and 36 carried between cross members l6 and I8; and in forward inner bearings 3| and 34 attached to frame cross-members l5 and Hi.

The carriage wheels are driven separately on the two sides of the carriage, by hydraulic motors 31 and 38, with suitable sprockets 39 and chains 40 to jack shafts 4| and. 42 mounted in outer bearings 43 and 44 attached to side members II and I2; and in inner bearings 45 and 46 attached to frame members 35 and 36 between [cross members [8 and I6. Sprocket 49 on the jack shaft 4! is arranged to drive the right rear drive sprocket 5|] by means of the chain 5|; and the sprocket 52 on the jack shaft 4| is arranged to drive the right front sprocket 53 by the chain 54. Likewise on the left side, the sprocket 55 on the jack shaft 42 is-arranged to drive the'left rear drive sprocket 56 by the chain 51; and the sprocket 58 on the jack shaft 42 drives the front left drive sprocket 59 by means of the chain 60. The hydraulic valves BI and 62 at the operator control station provide means for independently operating the motors 31 and 38, to move the flanged drive wheels on either side of the carriage, thus permitting control of the movement of the carriag to attain parallel forward motion. This is important since the temporary tracks for the carriage wheels, usually consisting of the headers 63 of the road strip, are not always in practice accurately placed or levelled. Hydraulic pumps 64 and 65, and liquid reservoir 66, with suitable connecting piping, are provided to actuate the fluid motors 31 and 38 and to connect with the control valves BI and 62, as shown in Figs. 1, 2 and 5.

Upon the main frame is mounted a gasoline motor 80, whose main haft is operatively connected to a generator 8I through the coupling 82. operating-the motors B1, 68, 10, 1I, and 13 actuating the fluid pumps 04, 65, 14, 1.5 and 16, and for driving the oscillating screed motor 11, :and the individual vibrator motors 84 of the vibrating units 69.

My machine is provided with a gang of separate vibratory units 69 of the general type consisting of an elongated tubular housing inclosing a rotary vibratory mechanism attached to a high speed motor, the tubular housing being at least partly insertible in the concrete. While I may use any suitable type of insertible vibrator, I prefer to use one in which a portion of the tubular casing is made semi-rigid or very stiifly flexible. In Fig. 7, the drive shaft 85 of the motor 84 is operatively connected to a vibrator mechanism by means of relatively short length of flexible shafting 86 connected to the vibrator rotor 81,

- this shafting being enclosed in a semi-rigid housing 88. The vibrator mechanism consists of an flexible metallic sheathing 94, and this is enclosed within the water-sealing tubing 95 which may be rubber-like composition with suitable metallic or fabric reinforcing to give the desired semirigidity and strength. When in the concrete, the tube is rigid enough to maintain itself insubstantially straight form but flexible enough so that it may be bent as much as ten to twenty degrees when sufiicient forc is applied. The advantages of using the semi-rigid tubular vibrator is that it permits the necessary bending either upwardly or laterally to carry thevibrator tubes around obstructions such as manholes and the like, which may be in the roadbed, and thus avoids the necessity of the operator withdrawing the entire gang of vibrators out of the concrete, and insures vibratory action near such obstructions. The semirigid tube also gives greater efficiency in the vibratory action because less energy is dissipated to the motor and from the motor to the supports on the machine.

Each of these vibrator units is supported on a movable cross-member 96 by means of a yoke 91 at the end of a leaf spring member 98 which is rigidly attached to the movable cross member .96. The gang of vibrators thus attached to the movable !CrOSS member 96 may be so'moved Iby elevator means that the free ends of the vibrator tubes are inserted into the concrete mass, and the tubes then take an operative. position inclining downwardly and rearwardly of the machine with the The generator supplies electrical energy for tubes partly buried in the concrete. As the whole machine moves forward, the vibrator tubes are combed through the mass in this inclined position. The elevator means provides not only for lifting the vibrator tubes out of the concrete by movement parallel to their long axes, but also means are provided to simultaneously move the elongated vibrator tubes from their inclined usual operative position gradually to a vertical position. This is desirable when lifting them over the expansion joints in the pavement, and it provides for vibrating the concrete throughout its thickness up to the joint and thus avoiding unvibrated pockets around th expansion joints; and for reinsertingthem on the forward side of the expansion joints. In order that the free ends of the vibrators in their main operative position be positioned under the oscillating screed member 19, the elevating means also provides for moving the gang forward or backwards relative to the: screed.

My preferred elevator means is shown on the machinein Figs. 1 and 2 and in detail in Figs. 8 to 14. Extensible lever members I00 are pivoted on the pin IOI in the clevis I02 attached at a fixed position to the main frame side member I I or I2 on the inside of the frame at positions intermediate the ends and preferably to the rear of the screed member. Additional elevating means may be provided between the side frame members when the width of the paving machine is such that more than the two shown here are required. The other end of the extensible lever I00 is pivotally-fastened to an attachment plate I03 by means of a clevis and piece I04 and pivot pin I 05.

Attachment plates I03 are welded or otherwise fastened to the vibrator supporting cross-member 96 near its ends.

The lever members I00 are adapted to be varied in length by means of a telescoping tube arrangement hydraulically actuated by pump 14 operable by motor 10 and controlled by a valve II 4. An outer tube I06 encloses an inner tube II3 (see Fig. 8) the latter being provided with a plug I01 at its inner end through which a pipe I08 allows fluid to be put in or removed from the fulcrum side of the fixed piston I09; and another pipe H0 is provided through a packing gland III in the plug I 01 this pipe being attached to and leading through the piston I09, which is provided with sealing rings H2. The pipe II 0 is adapted to deliver and return hydraulic liquid to and from the outer end of the tube I I3 which is closed by the plug end of the clevis end piece I041. The pipe IIO, fixedly secured to the tube I06, holds the piston I09 in fixed position relative to the outer tube I06. When it is desired to lengthen the lever arm I00, hydraulic, liquid under pressure under control by valve I I4 from the reservoir 66 and pump 14, actuated by motor 10, is forced through pipe IIO into the outer cylinder space causing the tube 1 I3 to move outwardly relative to tube I06. When shortening of the lever arm is required, liquid is forced into pipe .I08 causing the tube I I3 to telescope inside tube I 06 and thus shortening the arm I00.

A short telescoping lever arm H8 is attached to lever member I00 intermediate its ends by means of a clamp member II9 whose ends form a clevis in which one end of the arm H8 is pivoted by the pin I20, this short lever arm being also extensible and similar in construction to lever arm I00. A piston I25 with pressure rings I26 is provided inside an inner telescoping tube I21,

' its position being fixed relative to the outer tube I28 by the hollow piston rod or pipe I29 which is attached near the fulcrum end to the outer tube I28 and passesthrough a packing' gland I30 inthe inner tube end plug I3'I, which closes the inner end of tube I21. The hollow piston'rod I29 is'arranged to discharge pressure fluid into the space beyond the piston I25 in the inner tube I21, whose outer end is closed by the bifurcated end plug I2I. The hydraulic liquid is controlled by the valve I24 at the control board, which controls the fluid passing from the reservoir '86 to the pump 16 operable by the motor 13. The outer end I2I of the arm H8 is pivoted by pin I22 to a bracket I23 attached, for example by welding, near the end of the vibrator-supporting cross-member 98 and opposite the attachment plate I03, the pivoting pins I and I22 being separated and disposed relative to the supporting cross-member 96 so that the insertible tubes of the vibrator units 89 may be moved angularly from ayertical position to the operative inclined position as described above. The extensibility of the members I00 and H8 not only provides for the turning movement of the cross member 96 and its attached gang of vibrators, but it also allows positioning the vibrators forwardly and backwardly relative to the oscillating screed member 19.

The extensible lever arm I90 is turned on the fulcrum pin IIJI thereby elevating the cross-member 95 and its attached gang of vibrators, by means ofan hydraulic lifting jack I33 whose movable piston member I34 is provided with a cap 435 bearing against the lever arm member I00, preferably at the clamp member II9. The lever arm I90 is raised by positive action of the hydraulic jack but the weight of theattached parts permits downward movement against the jack. The jack I33 on either side is supported below the side members II or I2 by means of a bracket I35, and hydraulic liquid lines I38 and I31 from-the pump through the control valve H1 at the control station furnish the actuating pressure liquid. By manual manipulation of the valves controlling the lengthening and shortening of the lever arms I00 and I I8, and the lifting jack I33, the positions of the vibrators 69 and their insertible tube portions may be controlled ,at the beginning and ending of a paving strip, and in the operative position during passage through the length of the strip, at positions immediately below the oscillating cross-screed member 19. The several positions of the elevating and turning means and the vibrators are shown in Figs. 2 and 12.

Alternative arrangements for elevating and turning the vibrators mounted in a gang on the supporting cross-member 98 are shown in Figs. 15' to 19. Referring to Figs.' 15,16 and 1'7, which show the first of these alternative arrangements as applied to the right side of the carriage (it being clear that a duplicate arrangement of the left side of the carriage, and intermediate the sides if desired, may be provided), a long lever arm -I 65 is pivoted by Din I66 in the clevis bracket I61 mounted on the side member II of the carriage, the other end of the lever being pivotally attached to the hinge pin I68, this pin serving also as a fulcrum for the short lever arm I69. The short lever arm I59 has a short portion extending beyond the fulcrum at I 68, which is rigidly attached to the end of the vibrator supporting cross member 98; the other end of the lever arm IE9 is pivotally attache'dto'the piston rod I10 of the reversible hydraulic jack IN,

which'has its base pivotally attached to the car riage side member by a bracket I12, its point of attachment being forward from the fulcrum of the main lever arm I85. A second hydraulic jack I13 is also mounted on the bracket I14 attached to the'side member II, this jack being pivotally fastened to the long lever arm I85 intermediate its ends, by means of a pivoted link I15. Suitable hydraulic pipe lines for actuating the jacks HI and I13 are provided, with suitable valves at the control panel for manual operation by the operator. The jack I13 functions to lift the gang of vibrators vertically, and the short lever arm I with the jack I1I effects the turnr ing of the vibrator assembly around the axis of position beneath the screed member 19, and on occasion to bring it to a verticalposition and lift it' out of the concrete, as over a separator strip, and back again, by suitable manipulation of the two jacks HI and I13. 1

A second alternative elevating and turning arrangement is shown in Figs; 18 and'19. Along lever arm I is pivoted by the pin I8I on the bracket I82mounted on the side member II; its other end being pivoted by the hingepin to the piston I83 of the hydraulic jack I84, mounted on the side member II by bracket I85. Intermediate the fulcrum I8I and the hinge pin I86, is mounted the main jack I81 on the side member II, the extensible piston rod of the jack being fastened to the movable bracket I88. theilower end of which forms a seat for a third hydraulic jack I89, arranged so that jack I81 will raise and lower the third jack I 89. The third jack I89 is provided with a pivoted link member I90 which is pivotally attached at I92 also to the short lever arm I9I which is pivoted near its center on the hinge pin I86. The outer end of the lever arm I9I is rigidly fastened to the end of the vibrator supporting cross-member 98. Hydraulic lines, with control valves at the operators station, are provided to the three jacks. and by suitable operation of the jacks, the vibrators maybe made to take the various positions, as shown in Fig. 18, from the inclined operative position in the concrete beneath the screed member19 to the vertical position in and out of the concrete, as shown, thus permitting the vibrating of the concrete up to a dividing line such as an expansion joint member, with vertical reinsertion of the vibrator tube followed by positioning in the inclined operative position under the screed. The

use of the two jacks I81 and I89 instead of one long jack gives better operating control by limiting the movement in two steps limited by the length of lift of each jack.

Referring particularly to Figs. 1, 3 and 4, the cross screed'member consists of'a screed plate MEI-which is attached to the forward side of a screed frame I4I which extends'across the roadway and is provided with shoes I42 which slide on the top edge of the header or side boards 63. The vertical position of the screed plate is adjustable by hand wheels I43 at either end, and contour plates I 44 adjustably attached to the screed plate act to shape the concrete at the edge of the road or strip. Wings I45 are provided to push any spreading concrete back onto the roadbed. The screed frame is supported from the cranks I46 which are supported by. brackets 14,1 rigidly attached to the member I5. The forward end of each crank is provided with a roller I48 which supports the screed frame I under the channel iron brackets I49 onthe frame, this allowin horizontal movement of the screed frame corresponding to its oscillatory :movement across the strip. The free end of each bell crank is connected by a cable to the control wheel 150 so that'the operator may adjust the level of the screed as required during operation. ,The forward and backward thrust of the screed I40 and the screed frame I4 I at any position in their oscillating movement: is taken by the vertical rollers II which are mounted onbrackets I52 attached to the cross member I5, each rolling between three horizontal rolls I53, I54 and I55 attached to the screed frame MI. I

The oscillatory movement of the screed is provided by an arm I51 attached near the middle of the screed frame and driven by the motor 11 with its speed-reducing unit I59, a crank I60 being provided on its shaft Nil.

111- operating my machine along a strip which has been prepared fora concreteslab, including theslnsertion of the cross expansion-joint members, the machine is moved slowly over the area upon which unset concrete has been roughly distributed. The vibrators are lowered into theconcrete by means of the elevator mechanism as described and are combed through the levelledofilconcrete in an inclined position with the maximum amount of vibration being delivered in the concrete beneaththe screed. As the machine is advanced, the concrete is distributed, compacted and levelled off to the desired grade by the combined action of the vibrators and the oscillatin screed member placed directly above the operative inserted ends of the vibrators. Any entrapped air, and excess water followsup the vibrator tubes and the concrete mass becomes consolidated and no perceptible furrow is left by the vibrators because these are continuously closed behind the tubes. By means of my paving machine, much drier and harsher mixes of concrete may be properly placed on a roadway than has been possible by presently available methods. The surface may be further finished if desired by suitable means following the vibrators and screed.

While I have illustrated my invention by a preferred embodiment, I do not wish to be restricted to the particular arrangement. shown, but limit my invention only insofar as required by the prior art and the spirit of the appended claims.

I claim y 1. In a machine for compacting concrete on a roadway; the combination with a carriage frame of vibrator elevator means comprising a movable support member disposed crosswise of the machine adapted to holdas .a gang a plurality of individually actuatedelongated vibrator units, main lever means attached at fulcrums to the carriage frame for raising and lowering said support member including complete withdrawal of said units from the concrete space on the roadway, hydraulic jacks for moving said main lever means. and means to turn'said support member during operation to position and hold the elongated attached vibrator units in any selected rearwardly downwardly inclined position from the vertical; and a gang of tubular vibratory units held by said movable support member, each vibratory unit having an elongated casing part adapted for partial insertion in the unset concrete on the roadway and each unit having support member including complete withdrawal of said units from the concrete on the roadway, hydraulic jacks for moving said main lever means, and means to turn said support member during operation to position and hold the elongated attached vibrator units in any selected rearwardlydownwardly inclined position from the vertical in front of or beneath a screed memher; a gang of tubular vibratory units held by said movable support member, each vibratory unit having an elongated casing part adapted for partial insertion in the unset concrete on the roadway and each unit having independent actuating means attached to the non-insertible portion of said casing part, and anoscillating screed member supported by the carriage frame at the road surface and in normal operative position directly over said inclined vibrator parts submerged .in the concrete therebeneath.

3. In a machine for compacting concrete on a roadway, the combination with a carriage frame of vibrator elevator means comprising a movable support member disposed crosswise of the machine adapted to hold as a gang a plurality of individually actuated vibrator units each having an elongated vibratory casing part adapted for partial insertion in the concrete to deliver vibrations thereto, brackets attached to said support member for pivotal attachment of lever arms thereto, extensible main lever arms attached at fulcrums to the frame of said carriage and pivoted at the other end to said support member for raising and lowering said support member, means for varying the lengths of said main lever arms, hydraulic jacks for moving said main lever arms, extensible turning arms attached at fulcrums to said main lever arms intermediate the ends thereof and pivoted at their other ends to said brackets on said supportmember, means for varying the lengths of said turning'arms, said extensible arms, length varying means and brackets being arranged and adapted to position and hold the elongated vibrator casing parts in any selected rearwardly downwardly inclined position from the vertical; and a gang of tubular vibratory units held by said movable support member, each vibratory unit having an elongated casing part adapted for partial insertion in the unset concrete on the roadway and each unit having independent actuating means attached to the non-insertible portion of said casing part.

4. In a machine for compacting concrete on a roadway, the combination with a carriage frame of vibrator elevator means comprising a movable support member disposed'crosswise of the machine adapted to hold as a gang a plurality of individually actuated vibrator units each having an elongated vibratory casing part adapted for partial insertion in the concrete to deliver vibrations thereto, brackets attached to said support member for pivotal attachment of lever arms thereto, extensible main lever arms attached at fulcrums to the frame of said carriage and pivoted at the other end to said support member for raising and lowering said support member, means for varying the lengths of said main lever arms, hydraulic jacks for moving said main lever arms, extensible turning arms attached at fulcrums to said main lever arms intermediate the ends thereof and pivoted at their other ends to said brackets on said support member, means for varying the lengths of said turning arms, said extensible arms, length varying means and brackets being arranged and adapted to position and hold the elongated vibrator casing parts in any selected rearwardly downwardly inclined position from the vertical in front of or beneath a screed member; a gang of tubular vibratory units held by said movable support member, each vibratory unit having an elongated casing part adapted for partial insertion in the unset concrete on the roadway and each unit having an independent actuating means attached to the non-insertible portion of said casing part and an oscillatory screed member disposed at the road surface supported by said carriage frame in normal operative position directly over said inclined vibrator casing parts submerged in the concrete therebeneath.

5. In a machine for compacting concrete on a roadway, the combination with a carriage frame of vibrator elevator means comprising a movable support member disposed crosswise of the machine adapted to hold as a gang a plurality of individually actuated vibrator units each having an elongated vibratory casing part adapted for insertion in the concrete to deliver vibrations thereto, brackets attached to said support member for pivotal attachment of lever arms thereto, telescoping tubular main lever arms attached at fulcrums to the frame of said carriage and pivoted at the other ends to said support member for raising and lowering said support member, means including a fixed piston inside the closed movable inner tube and pipe lines for conducting pressure liquid to and from either side of said piston for varying the lengths of said main lever arms, hydraulic jacks for moving said main lever arms, telescoping tubular turning arms attached at fulcrums to said main lever arms intermediate the ends thereof and pivoted at their other ends to said brackets on said support member, and means for varying the lengths 1 of said turning arms including a fixed piston inside a closed movable'inner tube with pipelines for conducting pressure liquid to and from either side of said piston, said levers, turning arms, and length varying means and the brackets being arranged and adapted to position and hold the v '7. In a machine for compacting concrete on a roadway, the combination with a carriage frame of vibrator elevator means comprising a movable support member disposed crosswise of the machine adapted to hold as a gang a plurality of individually actuated vibrator units each having an elongated vibrator casing part adapted for insertion in the concrete to deliver vibrations thereto, main lever arms attached at fulcrums to the frame of said carriage for raising and lowering said support member, main hydraulic jacks for raising and lowering said main lever means, and turning levers for said support member pivoted intermediate the ends thereof to the ends of the main lever arms, the outer ends of said turning levers being attached to said support member and the other end being pivotally attached to a second hydraulic jack, adapted to position and hold the elongated vibrator casing parts in any selected rearwardly downwardly inclined position from the vertical.

8. In a machine for compacting concrete on a roadway, the combination with a carriage frame of the vibrator elevating and turning means of claim '7, and an oscillatory screed member disposed at the road surface supported by said carriage frame, and in normal operative position directly over said elongated vibrator casing parts submerged in the concrete therebeneath.

9. In a machine for compacting concrete on a roadway, the combination with a carriage frame of vibrator elevator means comprising a movable support member disposed crosswise of the machine adapted to hold as a gang a plurality of individually actuated vibrator units each having an elongated vibrator casing part adapted for insertion in the concrete to deliver vibrations thereto, main lever arms attached at fulcrums to the frame of said carriage for raising and lowering the said support member, main hydraulic jacks for raising and lowering said main lever means, turning levers for said support member pivoted intermediate the ends thereof to the ends of the main lever arms, the outer ends of said turning levers being attached to said support member and the other end being pivotally attached to a secondary hydraulic jack, secondary hydraulic jacks pivotally connected to said turning levers, and elevating hydraulic jacks attached to the carriage frame adapted to raise and lower 'the position of said secondary jacks relative to said main frame, said levers and jacks being arranged and adapted to position and hold the elongated vibrator casing parts in any selected rearwardly downwardly inclined from the vertical position.

10. In a machine for compacting concrete on a roadway, the combination with a carriage of I CHARLES W. PIERCE.

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