US3377933A - Road laying machine - Google Patents

Description

4 Sheets-Sheet 1 Filed July 14, 1965 l wg a as 38 u mA MD WY NR R A H S E L R A H C ATT YS April 16, 1968 c. H. DALE 3,377,933

ROAD LAYING MACHINE.

Filed July 14, 1965 4 Sheets-Sheet 2 I NVENTOR: CHARLES HARRY DALE ATT'YS April 16, 1968 c. H. DALE 3,37

' ROAD LAYING MACHINE Filed July 14. 1965 4.Sheets-Sheet 5 INVENTOR: CHARLES HARRY DALE AT T'YS April 16, 1968 c. H. DALE 3,

ROAD LAYING MACHINE Filed July 14, 1965 4 Sheets-Sheet 4 FIG. IO

FIG. H

INVENTOR: CHARLES HARRY DALE W MZM AT T'YS United States Patent 3,377,933 ROAD LAYING MACHINE Charles Harry Dale, Rock Island, 111., assignor to Pav- Saver Corporation, Rock Island, III., a corporation of Illinois Filed July 14, 1965, Ser. No. 471,876 9 Claims. (Cl. 94-45) ABSTRACT OF THE DISCLOSURE Road paving machine with cable and winch propulsion, spreading auger, tamper bar, strike-off plate with curbforming plate, power adjustable crown pan, reciprocable rear finishing screed, and telescoping frame.

This invention in general relates to a machine for laying a concrete roadway strip and providing a finished surface in a single pass of the machine. More particularly, the invention pertains to a machine of the aforesaid character adapted to form and finish a roadway strip in a single pass and simultaneously form, if desired, a curb section along a longitudinal edge of said roadway.

Briefly, the road paving machine of this invention is an integral machine which accomplishes complete paving and finishing requirements with one machine, one paving crew and in one pass of the machine. The concrete is poured between forms defining the width of the desired road strip. The machine of the invention, as it moves longitudinally along said forms, distributes, spreads, compacts, crowns (if desired) and finishes the roadway strip. It is capable of forming and finishing an integral curb along a longitudinal edge of the roadway without manual forming or finishing and further is capable of finishing concrete to tolerances of Ai-inch or less.

The paving machine of the invention is self-propelled by individual, separately controlled, self-powered drums which each wind a cable. The cables stretch ahead of the machine, and their respective ends are secured by wedging C-blocks or other anchors on the paving forms or the like. The cables may extend, for example, a distance in the order of 300 to 350 feet ahead of the machine, whereby the machine can be moved a distance of more than 300 feet before it is necessary to unwind the cable from the drums and re-anchor the wedging C-blocks or other anchors. The machine is further adjustable width-wise so that it can lay roadway strips of the desired width, e.g., widths of from about 12 feet to 15 /2 feet.

Another important feature of the machine of the invention is its adjustability for forming crowns from about 0 inch to 2 inches in the laid road strip. This adjustment is accomplished mechanically through mechanism driven by a reversible electric motor, thereby eliminating any down time of the machine for changing crown adjustment.

Still further, the paving machine of the invention is constructed in two sections, a front, concrete-spreader section and a main, concrete-finishing rear section. These two sections are joined together by a pin or bolt on each side of the machine, whereby the machine may be dismantled into the two sections merely by removal of two pins or bolts. This allows the separate sections to be loaded, transported, and unloaded as separate units by light equipment. A standard rubber-tired end loader or back hoe can be used to load or unload the sections and hauling thereof can be accomplished on a flat bed truck.

The break-down of the machine into components for purposes of description of the invention hereinafter includes:

(a) A power unit including an internal combustion engine driving an electric generator, and electric motors connected with the generator for performing the various power-drive functions of the machine.

(b) Frames for the two sections of the machine including frame members extending transversely to the direction of machine travel, which frame members telescope to provide the aforesaid width adjustment of the machine.

(c) The aforesaid front section of the machine which is attached to the rear section by the aforesaid pins, said front section including as components thereof guide wheels adapted to ride on the form rails, plus the auger and its associated curb compactor as hereinafter described.

((1) An auger extending transversely of the direction of machine travel for spreading the concrete massed ahead of the machine as it travels forwardly and a compactor comprising a paddle wheel on the curb side of the machine for use in forming an integral curb in association with a curb former on the strike-01f plate at the forward edge of the rear section.

(e) A vertically and rearwardly reciprocating tamper bar extending transversely to the direction of machine travel.

(f) A crown pan under the main frame section and associated mechanism for adjusting the crown curvature imparted to the road surface by the crown pan, plus a removable, curb-forming section on the curb side of the crown pan.

(g) A horizontally oscillating screed which is springsuspended on oscillating arms on the rear side of the rear frame section.

(h) A machine propelling unit including two power driven drums on opposite sides of the machine, upon which are wound cables anchored ahead of the machine as aforedescribed.

(i) A control system for operation by the machine operator, who rides on the machine, which control system controls the various electrical motors for operating the various units of the machine.

(j) Strike-off unit including a removable, adjustable curb forming plate on a vertically adjustable strike-off plate.

OBJECTS A general object of the invention is to provide a onepass road paving machine which distributes, spreads, compacts, crowns (if desired), and finishes a concrete roadway strip as it moves slowly forwardly.

Another general object of the invention is to provide a road paving machine of the aforesaid character which is operated by only one man.

Still another general object of the invention is to provide a road paving machine having a front, spreader section and a rear, finishing section which are readily separable, whereby the respective sections can' be separated for ease in loading, unloading and hauling.

Still another general object of the invention is the provision of a road paving machine adapted to form an integral curb, if desired.

Still another general object of the invention is to provide a width-adjustable road paving machine composed of a front section and a rear section, each of which has a width-adjustable frame including telescoping frame members extending in the width direction of the machine.

A more specific object of the invention is to provide a crown pan for a road paving machine and associated mechanism therewith by which the crown pan can be adjusted between a substantially flat configuration and an upwardly arched configuration through a motor-driven linkage assembly.

Another more specific object of the invention is to provide a crown pan for a road paving machine with a curved, curb section pan removably attached to the curb side of the crown pan.

Another more specific object of the invention is to provide a road paving machine embodying a reciprocable screed supported on reciprocation-imparting members by a spring suspension system,

Another specific object of the invention is to provide a road paving material-spreading auger embodying a paddle wheel curb compactor on the curb side of the auger.

Still another more specific object of the invention is to provide a road paving machine having a strike-off plate following the auger, which strike-off plate is provided with an adjustable, cur-b forming plate on the curb side.

These, as well as other objects, features and advantages of the invention as hereinafter described, will be more fully appreciated from the following description of a specific embodiment of the invention which is illustrated in the drawings, wherein:

FIGURES 1 and 2 are, respectively, front and rear perspective views of the embodiment on paving form rails, a portion of the strike-off plate in FIG. 1 being broken away to facilitate illustration of the tamper bar.

FIGURE 3 is a top plan view of said embodiment on paving form rails.

FIGURE 4 is a fragmentary, perspective view of the curb side of the auger, its paddle wheel curb compactor, and the adjustable, curb forming segment of the strikeoif plate.

FIGURES 5 and 6 are detail views in end elevation of the crown pan and its associated crown adjustment mechanism with the crown pan in flat and crown-forming, arched positions, respectively.

FIGURE 7 is a fragmentary, perspective view of the rear side of the curb section of the crown pan and further illustrates the detail of the spring suspension system for the reciproca'ble screed.

FIGURE 8 is a fragmentary, sectional view of the front portion of the crown pan and the adjacent, front frame structure of the rear section of the machine.

FIGURE 9 is a fragmentary, perspective view of one of the two removable pin connections between the front section and the rear section of the machine, together with adjacent structures of said respective section-s.

FIG. 10 is a section taken on section plane 10-10 of FIG. 3.

FIG. 11 is a top plan view, partly in section, of the auger shaft and the mounting thereof on the machine.

MAIN FRAME MEMBERS Referring to the drawings, the main frame members of the front section 14 comprise side-by-side, telescoping pairs of tubes 10 and 11 and 12 and 13, respectively. These telescoping tube pairs are length-adjustable for adjusting the width of the machine as hereinafter described.

The main frame members for the rear section 15 comprise a length-adjustable, front, main frame member 16 and a similar length-adjustable, rear, main frame member 17. Each of the main frame members 16 and 17 are composed of a deeper or larger channel frame 18, in the channel of which is slidably and telescopically nested a shallower or smaller channel 19 (FIG. 2). The lower surface of the channel 19 is supported in the channel 18 on an L-c'hannel 18a (FIG. 8) rigidly mounted in the deeper frame channel 18. The respective smaller channels 19 of the front and rear frame members 1 6 and 17 are connected by a side frame member 21 and another frame member 22. The frame members 21 and 22 move with the channels 19 when the latter are telescoped into or out of their respective channels 18 in the width adjustment of the machine.

The deeper or larger channels 18 are joined by two frame members 23 extending therebetween on the curb side of the machine and by additional frame members 24 and 25 toward the opposite side of the machine. The respective ends of the deeper channels 18 of the front and rear frame members 16 and 17 are joined at their ends by a side frame channel 20. Bolts or clamps may be used to lock the telescoping frame members in their respective", width adjusted positions.

POWER UNITS AND CONTROLS The road paving machine has a self-contained power unit comprising an internal combustion engine 26 mounted on the rear section 15. The engine 26 is mechanically coupled to an electric generator 27 mounted next to the engine 26 on the rear section 15. The generator 27 is eliectrica-lly coupled through cable 28 through a circuit breaker 29 to a motor control unit 30. The motor control unit 30 is mounted on a T-housing on which are provided four reversible motor control switches 32 and two toggle switches 33. These switches respectively are electrically connected by wiring (not shown) to four reversible electric motors and two non-reversible electric motors. The T-housing 31 and circuit breaker 29 are rigidly mounted on the top edge of a frame channel 34, which in turn is rigidly mounted on the front side of the rear section 16 by a front frame plate 35 (FIG. 8).

The four reversible motor control switches 32 are operable through the pivoting of manually-operated control arms on the respective switches 32. Such switches for motor reversing are conventional and need not be illustrated in detail.

The four reversible, electric motors comprise winchdrive motors 36 and 3-7 mounted in the rear corners of the rear section 15; an auger-drive motor 38 next to motor 36 and connected by a drive, later described, to the auger 46 at the front of the front section 14; and a crown pan adjustment motor 39 mounted on rear section 15 next to the internal combustion engine 26. The nonreversi'ble motors comprise the motor 40 mounted on the rear side of the rear section 15 for driving the screed and motor 41 mounted on the rear section 15 next to motor 39 for driving the tamper bar drive mechanism, later described.

FRONT SECTION The front section 14 has as its main frame support the a foredes cribed telescoping tubes 1014. The road paving material is dumped ahead of the machine. As the machine travels forwardly the road paving material accumulates against a strike-off plate 42 which is supported on tubes 10 and 1 1 by at least two adjustable supports 43, shown in detail in FIG. 4. These adjustable supports 43 allow the strike-off plate 42 to be moved upwardly or downwardly to provide the desired thickness of the road paving material which is allowed topass under the bottom edge of the strike-off plate 42. The supports 43 each comprise an L-bar 44 having a vertical leg Welded to the strike-off plate and a horizontal leg supported on the upper end of a bolt, the threaded shank of which is threadedly supported in a vertical tube 45 rigidly attached to tube 10 or 11, respectively.

An auger 46 operates ahead of the strike-off plate 42. It has auger flights 47 and 48 of opposite hand which work the road paving material from the center of the machine tow-ard the opposite sides when the anger is rotated in one direction and from the sides of the machine to the center when the anger is rotated in the opposite direction. The machine operator, who controls the direction of rotation of the auger 46 through one of the reversible motor controls such as 32, will rotate the anger in the direction required in order to keep a supply of road paving material accumulated across the entire length of the strike-off plate 42. The lower edges of the flights of the auger 46 are slightly above the bottom of the main frame of the machine, whereby the auger will not contact a form rail over which it passes (as would be the case when paving a narrower strip than the narrowest width for which the machine is designed) or over an already laid, hardened section of road (as might be the case when the machine is used to lay a widening strip on a formed road or when laying a second strip next to an already formed, hardened strip of a highway or street). In the latter case, one side of the machine, usually the side opposite the curb side, rests on and slides over the already laid, hardened strip.

The auger flights 47 and 48 are mounted on a tube 50 which telescopes over and is locked on the auger drive shaft 49, which extends less than the full width of the machine and telescopes in the tube 50. This telescoping allows additional auger flight sections to be mounted on shaft 49 at the curb side of the machine when the machine is widened from its narrowest width to a wider width. The curb side of the auger drive shaft 49 is rotatably journ'alled on a bearing 51 mounted in a forwardly extending arm '52. On the opposite side, the tube 50 is rotatably journalled in a bearing 53 supported on a similar, forwardly extending arm 54 on the opposite side of the machine.

A portion of the auger d-rive assembly is located beneath a cover 55. This portion of the drive assembly comprises a chain and sprocket drive 56 mechanically coupled to a gear box 57. The gears of gear box 57 are driven by a detachable, rotatable drive shaft 58 (FIGS. l and 9). The driving shaft 58 in turn is driven by a chain and sprocket drive (FIG. 3) mechanically coupled to the reversible electric motor 38.

The auger 46 may be further supported in its central portion in a bearing carried by the bearing support arm 60, which is rigidly mounted on the telescoping tubes 10, 11 and 1-2, 13. The cunb side of the auger 46 has a curb compa'ctor 61. The compac'tor 61 comprises a fou r bladed rpad'dle wheel 62 having the paddles mounted on a bulb 63. The hub 63 contains an over-running clutch (not shown) which mechanically couples the paddle Wheel 62 to the drive shaft 49. The paddle Wheel 62 rotates in the arrow direction shown in FIG. 4 so that its paddles push concrete adjacent the curb rail beneath the curb forming section of the strike-off plate 42. The overrunning clutch is connected so that the paddle wheel rotates in the arrow direction when the drive shaft 49 rotates in the same direction, but will come to a standstill when the shaft 49 rotates in the opposite direction. It is not desired to have the compactor paddle wheel 62 rotate in said opposite direction because it would tend to pull the road paving material away from the curb forming section of the strikeoff plate 42.

The cur b forming section of strike-oif plate 42 comprises a cut-away, lower corner at the curb side of strikeoff plate 42, over which may be mounted a curb forming plate 64 (FIG. 4). The curb forming plate 64 has a curved lower edge and is adjustable vertically by the provision of two vertical slots 65 through which the plate 64 is bolted to strike-01f plate 42. Thus, the curb forming plate 64 provides for minor adjustment of the mass of concrete which is allowed to pass beneath the curbed section of strike-off plate 42. Plate 64 is inverted when no cunb is formed, whereby the straight edge along the upper side (a's oriented in FIG. 4) becomes a lower, straight edge extension of strike-off plate 42.

The forwardly extending arms 52 and 54 each have forked forward ends 66 between which are rotatably journalle'd respective flange, guide wheels 67 which ride on the form rails 68 and 69. The guide wheels 67 guide the front section of the machine as it travels forwardly along the form rails 68 and 6-9. The rear part of arm 52 further carries a forked guide 95 ('FIG. 4) having downw-ardly depending bars which slide along opposite sides of the curb rail 68 to keep the machine from straying laterally and from thereby forming an irregular-curb section.

MACHINE PROPULSION The machine is propelled forwardly by a cable-winch drive comprising winches 70 and 71 on opposite sides of the forward portion of the rear section 15. The winches 70 and 71 are respectively rotatably mounted in winch housing 72 and 73 which are rigidly supported on the rear section. Each winch drum 78 is rotatably driven by respective, reversible electric motor 36 or 37 through a reduction gear assembly 74, a chain-sprocket drive 75 and a second chain-sprocket drive 76 coupled to the drive shaft 77 for winch drum 78. The winches 70 and 71 wind on their respective drums 78, cables 79 and 80 extending forwardly on opposite sides of the machine. Each cable has a loop end 81 at its forward end connected to a respective C-block form rail anchor 82 fitted over the top of the respective form rail as shown in FIG. 1. The C-block anchors 82 bits into the form rails when the cables are tightened by virtue of the slight twisting action imparted by attachment of the cable by cable loop ends 81 on one side of the anchors 82. Other anchors attachable to form rails, ground driven stakes, or the like, may be used, if desired.

The respective cables 79 and 80 each pass over an idler pulley 83. Each idler pulley 83- is rotatably and slidably mounted on a fixed shaft 84, which in turn is supported by U-frames 85. The latter, in turn, are rigidly mounted on the telescoping tubes 10 and 11.

TAMPER BAR The tamper bar 86 reciprocates vertically between the strike plate 42 and front frame plate 35. It is an elongated, horizontal bar supported by vertical bars 87 at opposite ends thereof. The vertical bars 87 include threaded upper ends 88 Which extend into the lower arm of a respective clevis 89 and are held therein by nuts threaded on the threaded ends 88 on opposite sides of the lower arm of the respective clevis 89. The upper arm of each clevis 89 is pivotally supported on the forward ends of rocker arms 90, the rearward ends of which are pivotally connected by link arms 91 to eccentrics 92 rotatably driven by a shaft 93 extending across the machine immediately behind frame channel 34. The rocker arms are pivotally supported at their mid points on the upper edge of the frame channel 34, whereby the rocker arms cause the tamper bar to reciprocate up and down. The tamper bar reciprocates in the concrete massed against front plate 35 to work the surface aggregate below the surface of the ultimate, finished strip. The depth of penetration of the tamper bar 46 into the road paving material can be adjusted by turning the nuts on the threaded upper ends 88 of the vertical bars 87.

The shaft 93 is rotatably driven by a chain-sprocket drive 94, which in turn in rotatably driven by a reduction gear assembly 95 of the non-reversible electric motor 41. Inasmuch as the respective clevis 89 is pivotally supported on the forward ends of rocker arms 90, the tamper bar has a downwardand rearward tamping motion because the forward motion of the machine tends to hold the tamper bar rearwardly against the front frame plate 35 when the tamper bar reciprocates in the concrete mass, in which it is buried during the operation of the machine.

REAR, FINISHING SECTION The rear section 15 has mounted on its rearward side a screed comprising an elongated screed pan 101 provided with nine cross frame bars 102. The screed is supported on three swing arms 103 pivotally connected through hinges 104 to the rear channel 18. As shown in FIG. 7, each arm 103 supports at its outer end the screed through a spring suspension system comprising a vertical pin 105 threadedly connected at its lower end by bolts 106 to any one of the cross frame bars 102 through the holes 113 therein. The pin 105 is slidably housed in a t hub 107 rigidly attached to the outer end of arm 103. The upper end of pin 105 is spring suspended by a coil spring resting at its lower end on hub 103 and having its upper end bearing against the nut 109 threadedly mounted on the upper end of the pin 105.

The screed reciprocates across the width of the strip in an oscillating motion on the pivot arms 103. It is driven in this motion by a link arm connection 110 pivotally connected to an eccentric 111 which is rotatably driven by the motor 40. The motor 40 is supported on the rear face of channel member 18 and has a cover plate 112 over the top thereof, said cover plate being attached to the upper edge of the channel member 18. The flanges 114 of the screed pan have slits 115 between frame bars to give the screed longitudinal flexibility.

CROWN PAN AND ITS ADJUSTMENT The details of the crown pan and its crown adjustment mechanism are illustrated in FIGS. -8. The crown pan 116 comprises a normally flat, flexible sheet 117 to which may be attached, if desired, a curved, curb section sheet 118. The curved, curb section sheet 118 is removably attached to the curb side of the sheet 117 by a pair of back-to-back L- channels 119 and 120, respectively rigidly secured to the abutting edges of the sheets 117 and 118. The L-channels are held together by removable bolts 121. The curb section sheet, therefore, may be removed in the event of the pouring of a strip without a curb and the replacement thereof by a fiat sheet section. Also, various contours of the curve of the curb forming section sheet are possible by the selection of the desired curb section for the particular job.

The curb section sheet 118 includes a flat, outer section 123 which rides along the curb rail 68 and a curved section 122 corresponding in curvature, as viewed from the front or rear edge thereof, to the desired shape of the curb to be formed. The weight of the curb side of the machine rests on the flat section 123 through the provision of two or more foot members 124 resting on the flat portion 123 and having threaded shanks which are rigidly, but adjustably, supported on a frame member of the rear section 15. The foot members are adjustable to compensate for different depths of curbs and/or the use of the machine for other purposes, i.e., when the curb section 118 is a substantially flat sheet. The side of the crown pan opposite the curb section slidably rides on the other rail 69 or on an already poured, hardened section of concrete, as heretofore described.

The crown adjustment mechanism 125 is shown in detail in FIGS. 5 and 6. The crown pan sheet 117 has fixedly attached thereto near its front and rear edges a pair of metal bars 126, such as T-channels, which extend in the width direction of the machine. Each metal bar 126 is connected by a plurality of link arms 127 to the crown adjustment mechanism. The central link arm is substantially vertical and the other arms diverge outwardly and downwardly relative to the center arm at increasingly greater angles of divergence from the center arm outwardly in opposite directions.

The link arms 127 each comprise a socket 128 pivotally connected to the respective bar 126 and a similar socket 129 pivotally connected to pivot bars 132 or 133. The sockets 128 and 129 are connected by a shank 130 having threads of opposite hand threaded into the respective sockets 128 and 129. Thus, each link arm 127 is lengthadjustable through threading rotation of the shanks 130.

Each of the two pivot bars 132 of the crown pan adjustment mechanism near the forward and the rearward edges of the crown pan is supported by a frame bar 134. The bar 134 has a pivot pin 135 on which is pivotally supported the outer end of pivot bar 132 and also the upper end of a triangular bar 136, the base of which is rigidly attached to the crown pan 116.

The outer end of pivot bar 133 is pivotally supported by a rigid frame member 154 of the frame section 15 on a rigid pin 155 attached to frame member 154. The outer end of bar 133- has a horizontal slot 156 which allows the outer end of pivot bar 133 to pivot and also axially slide relative to frame member 154 and its pin 155.

The two pivot bars 132 and 133 are substantially axially aligned as viewed in a horizontal direction when the 8 crown pan sheet 117 is substantially flat (FIG. 5). These bars overlap, being in side-by-side relationship as viewed from the top or bottom thereof. They are connected by a pivot pin 131, which is also the pin connection for the socket 129 of the center link arm 127.

As the pivot pin 131 raises, causing the pivot bars 132 and 133 to pivot upwardly about their respective pivot points on the pin 135 and pin 155, the link arms 127 pull the crown pan into an upwardy arched shape (FIG. 7). The center pivot link 127 moves the farthest distance upwardly, thereby positioning the apex of the crown pan arch substantially at the center pivot link 127. The other link arms 127 raise the crown pan to lesser degrees until the desired crown pan arch is achieved. The pivot links 127 also form rigid support members supporting the crown pan in its desired shape with the weight of the machine pressing downwardly on the concrete or other paving material passing underneath the crown pan 116.

The pivot bars 132 and 133 are pivoted to the desired position for the desired crown pan shape (flat or arched) by energizing reversible motor 39 through its control 32. Motor 39 drives the chain 139 to rotate sprocket 140. Sprocket 140 is joined with the sprocket 141 immediately therebelow, whereby the two sprockets rotate together. Sprocket 141 is connected by chain 142 with a sprocket 143. Sprockets 141 and 143, respectively, rotate on pillow blocks 144, which are rigidly mounted to the machine frame. Each of sprockets 141 and 143 have a threaded shaft 145 extending through the hubs thereof. Each vertical, threaded shaft, by virtue of its threaded connection with the hub of the respective sprockets 141 and 143, is raised or lowered when said sprockets rotate. The lower ends of the respective threaded shafts 145 are pivotally connected to one of the pivot bars 132 and 133, in the illustrated case the pivot bar 133. Thus, as the two shafts are raised or lowered together by equal velocity rotation of the sprockets 141 and 143 via drive chain 142, the inner ends of pivot bars 132 and 133 are raised while the outer ends pivot and slide on their respective supports 135 and 155. As the inner ends of the pivot bars rise, the crown pan is drawn upwardly via link arms 127 into the upwardly arched form as shown in FIG. 6. When electric motor 39 is reversed, the inner ends of pivot arms 132 and 133 drop as the threaded shaft 145 drops through reverse rotation of the sprockets 141 and 143.

The bar 126 and pivot arms 132 and 133 are provided with extra holes '138 and 137 respectively, for mounting the link arms 127 and pivot pin 131 in different positions when the machine is widened.

A detail view of the front edge of crown pan 116 is shown in FIG. 8. The front edge has an elongated, upwardly extending lip 146 which overlaps the lower edge of the front plate 35. In order to prevent road paving material from spilling over onto the upper side of crown pan 116, the upper edge of lip 146 and the front face of the front plate 135 are filled with a strip of calking compound 147. This strip of calking compound seals the space between front plate 35 and lip 146. It is replaced or repaired ordinarily only after each occasion of crown pan adjustment, in which case the calking is disturbed to a greater or lesser extent as the lip 146 moves up or down relative to front plate 35 during the changes in arch of the crown pan. The lip 146 is split at spaced points like the flanges 114 of the screed to facilitate flexing of the crown pan.

COUPLING OF FRONT SECTION TO REAR SECTION The square shaft 58 for driving the auger 46 is telescoped in a square socket of hub 148 of a double clevis, universal joint 1'49. Shaft 58 slides out of the socket of hub 148 when the front and rear sections 14 and 15 are separated. This allows the portion of the drive for auger 46 on the rear section 15 to be disconnected from the remainder of the auger drive on the front section 14.

On each side of the front section along its rear edge there is provided a frame member 150 having an upwardly projecting block 151. This block 151 sits inside a U-bar, which is rigidly attached to the front plate 35. The block and side legs of the U-bar have aligned holes through which removable fastener pins or bolts 153 extend. Thus, the only connections between the front section and the rear section are the two pins or bolts 153 at the respective sides of the sections. When bolts or pins 153 are removed, the front and rear sections can be separated and fan be handled individually in loading, unloading, or the ike.

ONE-MAN OPERATION OF MACHINE The machine operator stands on a platform 157. From this platform he can operate the various controls of control unit 30. He can steer the machine by controlling the relative speeds of the winches 70 and 71 and can also negotiate curves in the same manner. From the platform 157, the operator can observe the distribution of the accumulated concrete immediately ahead of the strike-off plate 42 and can control the speed and direction of rotation of the auger 46 in order to maintain the proper distribution of concrete, or the like. He can also observe the surface quality of the screed-finished strip and, if necessary, stop the machine to make proper adjustments in the spring suspension of the screed, the crown pan, the vertical height of the strike-off plate, or the like.

WIDTH ADJUSTMENT For most convenient width adjustment, the front and rear sections 14 and 15 are separated. The front section 14 is widened by uncoupling the bolts or clamps used to hold telescoping tubes -13 in their width-adjusted position. Similarly, the bolt attachment of anger shaft 49 to auger tube 50 is removed. If necessary, an additional auger section is inserted over the shaft 49 and coupled thereto. Similarly, an additional plate section may be coupled on strike-off plate 42.

The steps for widening the rear section include relative sliding of telescoping frame channels 18 and 19 to the desired width after uncoupling pivot 131 and the link arms 127 on pivot bar 133, which is on the curb side of the machine. A wider tamper bar may be substituted. A flat section may be added between the crown pan section 117 and curb section 118. A screed section may be added to screed 100. The link arms 127 for bar 133 are remounted in the additional holes 137 and 138 provided in bar 133 and T-channel 138, and pivot pin 131 is relocated in aligned holes 137 of bars 132 and 133. Length adjustments of link arms 127 may be in order due to relocation of some of the link arms. A plate section may be added to front plate 35 below the extended portion of the smaller, front channel 19.

Motor 39, the chain-sprocket drives thereof, self-aligning pillow blocks 144, shafts 145, and pivot bar 132 keep their initial relationship, which is not affected during width adjustment. Frame member 154 and pivot bar 133 move laterally with the frame section composed of front and rear frame channels 19, the frame members 21 and 22, and the motor 37 and winch 70 mounted thereon.

It is thought that the invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous changes may be made in the form, construction and ar-' rangement of the several parts without departing from the spirit or scope of the invention, or sacrificing any of its attendant advantages, the form herein disclosed being a preferred embodiment for the purpose of illustrating the invention.

The invention is hereby claimed as follows:

1. A paving machine comprising a front section and a rear section, frame means for said rear section including telescoping frame members extending the width direction of the machine, a power unit for said machine on said frame means, means powered by said power unit for propelling said machine forwardly, a crown pan comprising a large sheet beneath said frame for shaping the upper surface of the paving material passing beneath said sheet as the machine moves forwardly, said sheet being essentially stationary with respect to said frame means and extending substantially the width of said frame section with the outer edges of crown pan adapted to ride on concrete strip form rails or a hardened concrete strip next to the strip being laid by said machine, a frame means on said front section including telescoping frame members extending the width direction of the machine, a spreading auger extending across said front section, a strike off plate on said front section immediately behind said auger, tamper means for tamping the road paving material behind said strike off plate and ahead of said crown pan, said strikeoff plate having an elongated lower edge and adapted to form a layer of road paving material at the desired depth beneath said edge, a curb-forming plate at the lower corner of said strike-off plate, the lower edge of said curbforming plate corresponding substantially in shape to the contour of a curb to be formed of said road paving material, another edge of said curb-forming plate being a straight edge adapted to be aligned with said lower edge of said strike-off plate, and means mounting said curbforming plate on said strike-off plate for selective orientation of said edges of the former plate relative to said lower edge of said strike-off plate to form a roadway with or without an integral curb.

2. A paving machine as claimed in claim 1 wherein said telescoping frame members of said front section are telescoping tubes.

3. A machine as claimed in claim 1, wherein said tamper means is a horizontal, elongated bar extending in said width direction, and power-driven means for reciprocating said tamper bar in an up-and-down motion and including vertical support members rigidly connected at their lower ends to said tamper bar and pivotally supported at the upper ends of said support members for free front to rear swinging of said members and said tamper bar, where-by said tamper bar has a downward and rearward tamping motion during forward motion of said machine as said tamper bar reciprocates in the concrete mass.

4. A road paving machine comprising means on the front side of said machine for spreading road paving material and forming a layer of said material in strip-form, a crown pan comprising a large slightly flexible sheet on the underside of the rear portion of said machine and extending substantially the width of the machine, and reversible drive power means operatively connected via mechanical linkages to said crown pan for selectively shaping said crown pan in either substantially flat or upwardly-arched form as viewed from the front or rear of said crown pan, said mechanical linkages being characterized by a pair of pivot bars having their outer ends pivotally supported on frame members of said machine, the inner ends of said bars being connected to said reversible power driven means by mechanical means for raising and lowering said inner ends thereof, link arms depending from said bars, and pivot means pivotally connecting the respective ends of said link arms with said pivot bars and said crown pan to draw said crown pan into said upwardly-arched form as said inner ends are raised.

5. A machine as claimed in claim 4 wherein said mechanical linkages includes a rotatable member through which extends a vertical shaft threadedly connected with said rotatable member for moving said shaft up and down as said member rotates, and means on the lower end of said shaft pivotally connecting it to one of said pivot bars.

6. A machine as claimed in claim 4, and means on respective link arms for adjusting the respective lengths thereof.

7. A screed assembly for a road paving machine comprising an elongated, horizontal screed, a plurality of horizontally spaced arms with hinge means on the inner ends thereof to pivotally mount said arms on a road paving machine for oscillation in a substantially horizontal plane, a plurality of vertical shafts connected to said screed at spaced points therealong, a hub on the outer end of each arm with a vertical passage therethrough, said shafts slidably extending through respective passages of said hubs and projecting thereabove, a nut threaded on the upper end of each shaft, a coil spring about each projecting portion of said shaft between the nut and the hub and spring-suspending said screed on said arms, and power means operatively connected to said screed for longitudinally reciprocating said screed.

8. A crown pan and crown adjustment assembly comprising an elongated, slightly flexible, horizontal crown pan sheet, a pair of pivot bars together extending as a unit longitudinally of and above said crown pan sheet, the inner ends of'each bar being above the longitudinal mid-portion of said sheet and overlapping each other, a pivot pin connecting said inner ends, a row of a plurality of link arms extending between said pivot bars and said sheet, means pivotally connecting the upper ends of respective link arms to respective pivot bars and the lower ends of respective link arms to said crown pan sheet at 5 longitudinally spaced points thereon, means for pivotally supporting the respective outer ends of said pivot bars,

and means for raising or lowering the inner ends of said pivot bars to pivot said bars in a vertical plane to flex said sheet into a desired shape of either substantially flat or upwardly arched shape.

9. An assembly as claimed in claim 8 wherein said lastmentioned means is power driven by a reversible electric motor.

References Cited UNITED STATES PATENTS 1,619,083 3/1927 Maxon 94-45 2,006,316 6/1935 Mandt 94-44 2,038,416 4/1936 Clifford 9448 2,090,959 8/1937 Jackson 9448 X 2,397,782 4/1946 Flynn 9440 2,623,446 12/ 1952 Clark.

2,999,433 9/1961 Baltes 9445 3,005,387 10/1961 Heltzel 94--45 3,015,258 1/1962 Apel 94-46 3,155,021 11/1964 Sauer et al. 9445 3,221,618 12/1965 Hudis 94--46 X 2,168,507 8/1939 Barber 94-45 3,247,770 4/1966 Perkins et a1. 9445 CHARLES E. OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, Examiner.

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