US1982387A

US1982387A - Road building machine

Info

Publication number: US1982387A
Application number: US223161A
Authority: US
Inventors: John N Heltzel
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-09-30
Filing date: 1927-09-30
Publication date: 1934-11-27
Anticipated expiration: 1951-11-27

Description

Nov. 27, 1934. J,'N. HELTZEL I 1,982,387

ROAD BUILDING MACHINE Filed Sept. so, 192'? 7 Sheets-Sheet 1 1' W muuunun- I Q Q attorney Nov. 27, 1934. J. N. HELTZEJL I 1,982,387

' ROAD BUILDING MACHINE Filed Sept. 50, 1927 7 Sheet s-Sheet 2 atkoz may 2 3 J. N. HELTZEL I ROAD BUILDING MACHINE Filed Spt'. so. 1927 '7 Sheets-Sheet 3 attoz new Nov. 27, 1934. J. N. HELTZEL ROAD BUILDING MACHINE Filed Sept? 50, 7 Sheets-Sheet 4 QM m H H n U n n n H Nov. 27, 1934. J. N. HELTZEL 1,982,387

ROAD BUILDING MACHINE Filed Sept. 30, 1927 7 Sheets-Sheet 5 Nov. 27, 1934. J. N. HELTZEL 1,982,387

ROAD BUILDING MACHINE Filed Sept. 30, 1927 7 Sheets-Sheet 6 Nov. 27, 1934. J, N, HELTZEL 11,982,387

ROAD BUILDING MACHINE Filed Sept. 30, 1927 7 Sheets-Sheet 7 F/Zi 1.3.

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Patented Nov. 27, 1934 UNITED STATES PATENT OFFICE 44 Claims.

The present invention relates to concrete road machines, and aims to provide a novel and improved road building machine capable, after the aggregate is deposited between the side forms or rails, of completing the road and including provisions for producing longitudinal and transverse joints in the road.

Other objects of the invention are the provision of such a machine having novel screeding or strike-off means, novel joint producing and installing means for both longitudinal and transverse joints, novel surface finishing means, and other novel devices to facilitate the building of the road.

With the foregoing and other objects in view, which will be apparent as the description proceeds, the invention resides in the construction and arrangement of parts, as hereinafter described and claimed, it being understood that 90 changes can be made within the scope of what is claimed, without departing from the spirit of the invention.

The invention is illustrated in the accompanying drawings, wherein- Figs. 1 and 1A are longitudinal sections of the front and rear portions of the machine, respectively.

Fig. 2 is a front view of the machine showing the screeding device, portions in rear being omitted.

Fig. 3 is a plan view of the forward portion of the machine, portions above the frame being omitted.

Fig. 4 is a cross section on the line 4-4 of Fig.

1 showing a transverse joint producing or cutting device.

Fig. 5 is a transverse section on the line 5-5 of Fig. 1 showing the transverse expansion joint installing device.

41) Fig. 6 is a transverse section on the line 6-6 of Fig. 1A showing the longitudinal joint depressing device.

Fig. 7 is a transverse section on the line 7-7 of Fig. 1A showing the transverse contraction joint installing device.

Fig. 8 is a transverse section on the line 8-8 of Fig. 1A showing the floating or smoothing device.

Fig. 9 is a transverse section on the line 9-9 of Fig. 1A showing the longitudinal joint finishing and one of the side edging tools.

Fig. 10 is a detail view of one of the hold-down devices for the carriage or wheel-mounted frame.

Figs. 11 and 12 are plan views of different concrete roads constructed in accordance .with

the present invention, and showing variations in road building.

Fig. 13 is a perspective view of a dowel placer for positioning the dowels of the transverse contraction joints. 7

Fig. 14 is a perspective view of a dowel unit for the transverse contraction joint.

Fig. 15 is a side elevation of a modified form of longitudinal joint producing and installing. device, showing the screed in cross section.

Fig. 16 is a section on the line 1616 of Fig. 15.

Fig. 17 is a cross section of the transverse expansion joint installing blades in the concrete and receiving the expansion joint strip between them.

Fig. 18 is a corresponding view showing a form deposited between the blades.

Fig. 19 is a cross section of a transverse expansion joint completed by the use of the strip shown in Fig. 18 or the form shown in Fig. 18.

Fig. 20 is a cross section of a modified form of contraction joint and device for depositing the joint strip in the concrete.

Figs. 21 and 22 are front end views showing modified forms of longitudinal joint producing blades.

The carriage of the machine comprises a suitable structural frame I mounted on wheels 2 that travel on. the side forms or rails 3 between which the road is constructed. The wheels 2 are adjustable transversely on transverse axles 4 in order that the machine may be employed for roads of different widths.

Hold-down devices are employed to hold the machine down on the rails 3, and these devices as shown are secured to the axles 4 so as to be associated with the wheels. Each hold-down device includes a roller 5 to engage the corresponding rail 3. A collar 6 is secured adjustably on the axle 4 by means of a set screw, or .the like, and has a depending rod 7 on which a tube 8 is slidable, said tube carrying the roller 5. The rod 7 has a pin 9 projecting through slots 10 in the tube 8 to prevent said tube from turning, and a coiled spring 11 is confined between the pin 9 and an adjustable nut or collar 12 on the tube, to thereby yieldingly raise the tube 8 and roller 5. These hold-down devices will, by the action of the springs 11, hold the wheels 2 down on the rails, to prevent the frame from being lifted due to the action of the several devices when operating on the aggregate or plastic concrete. The collars 6 may be adjusted on the axles 4 with the wheels 2. ""110 Screedina device The screed or strike off 13 (Figs. 1, 2 and 3) comprises a plate extending transversely of the road and having its end portions bearing slidably on the rails 3, and the screed 13 has the front and rear

upstanding flanges

14 and 15, respectively. The front flange 14 is of sufficient height to serve as a baffle and prevent the aggregate from passing thereover, the surplus aggregate in front of the screed, as seen in Fig. 1, being pushed ahead by said flange or bafile 14 as the machine advances.

An I-beam 16 is secured on the screed 13 between the flanges, and said screed and beam are curved longitudinally to the desired crown or convex curvature of the road transversely thereof. The screed 13 has slots or openings 17 therein in front of the beam 16 or in the forward portion of the screed behind the flange 14, so that the surplus fine material may pass upwardly through said openings into the pocket between the beam 16 and flange 14. The material may flow downwardly to fill depressions or voids, thereby avoiding such depressions and. voids which might otherwise occur. The rear portion of the screed 13 is imperforate so as to strike off or screed the material smoothly behind the openings 17.

In order to hold the screed down on the rails 3, rollers 5' bear on the end portions of the beam 16 and are carried by vertical rods 8' slidable in the frame and yieldingly depressed by coiled springs 11 confined between the frame and adjustable nuts or collars 12 on said rods. Adjustable nuts or collars 6' on the rods 8' are provided to limit the upward and downward movements of said rods and rollers. The screed may thus be held down on the rails by the force of the springs 11' or by screwing the lower nuts 6 upwardly against the frame. The rods 8' may be mounted to move forwardly and rearwardly with the screed, such as by oscillating or sliding brackets 8", so that the rollers 5 may remain in longitudinal grooves in the beam 16 as the screed is moved forwardly and rearwardly.

The screed is given a compound movement. It is not only reciprocated longitudinally of itself transversely of the road, as customary in machines of this kind, but the screed is also given a forward and backward or oscillatory motion simultaneously with the reciprocation thereof.

The reciprocation of the screed is produced by a link 18 connecting the beam 16 with an eccentric 19 on a longitudinal shaft 20 on the frame driven from the engine 21. Said engine furnishes the power for operating the machine and one or more of the wheels 2 may also be operably connected by suitable means 22 with the engine for propelling the machine. The link 18 is connected by flexible joints with the beam 16 and band of the eccentric 19 to permit of the different movements' of the screed.

The forward and rearward motion of the screed is produced by links 23 connected by universal or flexible joints 24 with the beam 16 at opposite sides of the longitudinal center of the machine, and connected to eccentric bands 25 mounted on eccentrics 27 secured to a transverse shaft 27 mounted on the frame and driven from the engine 21. The eccentrics 26 are oppositely disposed with reference to the axis of the shaft 27, so that when one link 23 is being moved forwardly the other link is being moved rearwardly. This will give the screed 13 an oscillatory motion so that its opposite ends move forwardly and rearwardly in opposite directions. This oscillatory motion of the screed may be synchronized with the reciprocation of the screed to obtain an effective screeding of the aggregate. Thus, referring to Fig. 3, which shows the screed in its intermediate position, when the screed is moved toward the left, the left hand end of the screed is moving rearwardly and the right hand end of the screed is moving forwardly, so that the right hand half of the screed will push forwardly against the aggregate with a. swinging movement while the screed is moving toward the left. This will have a tendency to move the surplus aggregate in front of the screed toward the center of the road. Then, when the screed is moved toward the right the right hand end of the screed is moved rearwardly and the left hand end of the screed is moved forwardly, so that the left hand half of the screed is moved forwardly with a swinging motion against the aggregate while moving toward the right, thereby working the aggregate toward the center of the road. The combined reciprocatory and oscillatory movement of the screed will also produce a desirable screeding action on the material, and owing to the oscillatory movement of the screed it will alternately act on the material at the opposite sides of the longitudinal center line of the road, thereby working the material toward the center of the road away from the side rails, as well as advancing the surplus aggregate without the surplus material laying I against the screed throughout the length thereof, which reduces the resistance to forward movement of the machine.

It is preferable to vibrate the screed during the operation thereof, and this is accomplished, as shown, by compressed air hammers having their cylinders 28 mounted on the frame and their plungers 29 arranged to contact with the beam 16, so as to impart rapid blows on the screed during the movement thereof. The cylinders 28 are supplied by compressed air from a supply pipe 30 communicating with a compressed air tank 31 into which air is pumped from a pump driven by the engine 21, and a valve 32 controls the flow of air to the cylinders 28.

Longitudinal joint producer Associated with the screed is a device (Figs. 1, 2 and 3) for separating the stones or coarser aggregate along the line of the center joint. This device comprises a longitudinal vertical blade or bar 33 below the screed 13 and extending forwardly and rearwardly beyond the screed. The blade 33 has the upwardly projecting supporting arms 34 at its forward and rear ends, and said arms are provided with vertical slots 35 receiving clamping bolts 36 carried by the frame 1 to enable the blade 33 to be adjusted to the desired vertical position. The bolts 36 may be loosened to permit the blade 33 to move vertically. Coiled springs 37 are disposed on vertical rods 37' secured to the frame and the upper ends of the arms 34 are slidable on the rods between said springs to yieldingly maintain the blade 33 in the desired position. The lower springs 37 are confined between the upper ends of the arms 34 and the frame, while the upper springs 37 are confined between the arms 34 and adjusting nuts 37" on the rods. 1

With this arrangement the aggregate is struck off or screeded over the blade 33, and said blade will therefore separate the stones, pebbles or larger aggregate, for a predetermined depth below the upper surface of the road. This separation takes place in front of and below the screed, so that the blade 33 will move in the material with minimum resistance, the front end of said blade projecting beyond the loose material in advance of the screed. The screed 13 reciprocating across the blade 33 will vibrate said blade laterally to separation of stone or other coarse aggregate. The stone or other coarse aggregate will remain separated in rear of the blade 33 although the fine mortar aggregate may flow into the space in' rear of the blade 33 as the blade is advanced. However, the fine material or mortar in the line of the joint will not interfere with the installation of non-rigid joint material and the finishing of the joint, as will hereinafter appear.

The blade 33 leaves behind it a weakened line in the concrete, and although the sand and finer material may flow together behind the blade 33, the concrete will not knit together behind the blade 33, that is, with stones or coarser aggregate extending across the line of the blade 33, excepting at a depth below the lower edge of the blade. Consequently, the tools following in rear for producing or installing a longitudinal joint will not have to displace stones or larger aggregate. Furthermore, the blade 33 may produce a weakened line in the concrete to control the longitudinal breaking of the concrete after it has set, inasmuch as the longitudinal break will occur in. the line of least resistance or along the line of greatest weakness. The stones or larger aggregate being separated by the blade 33 will leave a line of weakness so that the longitudinal break will follow this line and will be substantially straight or regular, instead of the break occurring along irregular lines such as happens when the longitudinal breaks are permitted to develop at random without control.

The blade 33 may also be used as a depositor for depositing a strip of paper, metal or other material in the concrete behind said blade. As seen in Fig. 2, the blade 33 has a passage or opening 33a extending longitudinally thereof from end to end, and a strip may be inserted rearwardly through the blade so as to be embedded in the concrete behind said blade as the machine moves forwardly. The strip may be continuous, or strips of predetermined length may be inserted so as to be disposed end to end, or material may be delivered into the blade, such as an asphalt or bituminous composition, oil, or other liquid or plastic material, to provide a longitudinal joint or weakened line in the concrete. For this purpose the forward end of the blade 33 projects forwardly beyond the screed or crowning means sufliciently far so as to protrude beyond the loose material in advance of the screed or crowning means, thereby permitting the strip or material to be moved rearwardly into the blade beyond the material. The strip or material delivered intothe blade will emerge from the rear end thereof so as to be deposited in the concrete behind the blade, without it being required to force the strip or material into the concrete. The material delivered into and through the blade 33 may either be premolded, such as strips of paper, metal, asphalt, or the like, or the material may be plastic so as to be molded by the blade 33 into thedesired shape when emerging from the rear end of the blade. As seen in Fig. 2 the passage or opening 33a is elongated vertically, whereas in Fig. 21 the passage 33b is of tapered cross-section, being wider at the lower edge than at the upper edge. Fig. 22 shows the passage 33c of angular form, and various other shapes of passages may be used for strips or joints of different forms. The passage through the blade may also be such as to fold or bend a strip entering the blade into desired form in cross- ,section when emerging from the blade. prevent honey-combing, in order to facilitate the \l The forward end of the blade 33 projecting beyond the loose material in advance of the screed will eliminate the necessity for the blade 33 being forced forwardly into the material, and the blade merely has to slip or slide forwardly in the material surrounding the blade in rear of its forward end, thereby reducing the resistance or friction to a minimum. The loose material is placed in front of the screed or crowning means over the blade behind the forward end thereof, and is then crowned off or screeded over the blade 33.

Tamper Behind the screed is a tamper 38 (Figs. 1 and 3) which is carried by plungers 39 slidable in the frame, and springs 40 are provided for forcibly depressing the tamper when it is released. The plungers 39 have their rollers 41 cooperable with cams 42 on the shaft 27, whereby the cams raise the plungers 39 and tamper 38 and then release said plungers, so that the springs 40 force the tamper down with a sharp blow against the surface of the concrete. The tamper is reciprocated vertically so as to tamp the concrete.

The tamper and its actuating means is of well known construction, but is equipped, in addition, with a depending blade 43 that may be removable or adjustable. This blade 43 being reciprocated vertically will cut the concrete on the line of the longitudinal joint, in rear of the blade 33, and this blade 43 may be used by itself in some instances for producing a longitudinal groove or cut in the road, to control the longitudinal break of the concrete. In this way the longitudinal joint may be formed simultaneously with the tamping of the aggregate.

Surface smoothing device In rear of the tamper is arranged a device (Figs. 1 and 3) for smoothing the surface of the plastic concrete, and said device includes the parallel bars 44 extending transversely across the road and secured to T-irons 45. The bars 44 may be of laminated wood or other suitable flexible material, with their edges rounded. The T-irons 45 are carried by levers 46 suspended from the frame, and a vertical shaft 47 is secured to one lever and is operably connected with the shaft 20, for oscillating said shaft and thereby reciprocating the bars 44 in opposite directions. As shown, the upper end of the shaft 47 has an arm 48 engaging a cam 49 secured on the shaft 20 to impart oscillatory motion to the shaft 47. The bars 44 thus reciprocate in opposite directions and will smooth the surface of the concrete. Consequently as the machine proceeds the coarser particles of the concrete material are displaced transversely and the finer portions of the concrete material enter into the space previously occupied by such coarser particles, this action being assisted by the smoothing or finishing members 44. Thereafter when the filling or joint material is inserted, the finer portions of the material will, of course, be displaced from the joint space.

Transverse joint producing device A device (Figs. 1 and 4) for cutting the semiplastic concrete transversely is carried by the machine in rear of the surface smoothing device, and includes a carriage 50 having wheels 51 traveling upon a pair of transverse rails 52 carried by the frame 1. Rollers 53 are carried by the carriage 50 and are disposed below the upper flanges of said rails to hold the wheels 51 down on said rail. A shaft 54 is mounted in the carriage 50 and has a flywheel 55 thereon provided with a crank 56 for manually rotating said shaft, although suitable power may be provided for operating the shaft, and said shaft is connected by a sprocket chain 57 or other suitable operative connection with the wheels 51, so that the rotation of the shaft will propel the carriage on the rails 52. The cutter or spader 58 projects downwardly between the rails 52, and is slidable on a guide pin 59 mounted in the carriage, and said spader has an eccentric band 60 at its upper end embracing the eccentric 61 on the shaft 54, so that the rotation of the shaft will reciprocate the spader vertically, thereby forcing the spader downwardly into the concrete and withdrawing the spader alternately. The spader may thus be reciprocated for cutting the concrete transversely from the surface to the sub-base. The rails 52 may be straight and at right angles to the longitudinal line of the road, or may be arranged obliquely, or may be of different forms, to cut the road along the desired line from edge to edge of the road.

Transverse expansion joint installing device A combined tamping and joint installing device (Figs. 1 and 5) for installing transverse expansion joints is mounted in rear of the transverse joint cutting device, and includes a pair of down wardly extending blades 62 extending transversely of the road and of a shape to correspond with the cut made by the spader 58, the machine being advanced, after the spader 58 has com-,

pleted the transverse cut, so that the blades 62 register with the cut made. The blades 62 are secured to the lower arms of levers 63 fulcrumed, as at 64, to slides 65 mounted for vertical sliding movement in the frame 1, and right and left hand screws 66 connect the upper arms of the levers 63 for swinging said levers to move the blades 62 together and apart. The blades 62 are moved upwardly and downwardly by means of vertical screws 67 mounted in brackets 68 secured on the frame 1.

Air hammers are provided to impart blows on the blades 62 for driving them downwardly into the concrete. These air hammers create a vertical vibration or up and down motion of the blades 62, so that the upper outstanding flanges of said blades produce a tamping action of the joint installing device, as will hereinafter more fully appear. These air hammers, similar to those used with the screed, are of well known construction, and comprise cylinders 69'carried by the frame 1 and plungers '70 projecting from the lower ends of the cylinders to impinge against the blades 62. The cylinders 69 are supplied with compressed air from the supply pipe 30 through a control valve 71.

In operation, with the blades 62 located above the transverse cut produced by the spader 58, the screws 66 are rotated to bring the blades 62 together, as seen in Fig. 1. and the screws 67 are then rotated to force the blades 62 downwardly. During the downward movement of the blades 62 the air hammers may be operated so that the blows of the plungers 70 on the blades 62 will blades into the concrete, as a unit. When the assist in driving the blades down into the concrete, said blades entering the cut made by the spader 58. The blades 62 are then separated by turning the screws 66 so as to swing the levers 63, and the premolded expansion joint strip 72 may then be inserted between the blades 62, as seen in Fig. 17. The blades 62 are then withdrawn from the concrete by raising the slides 65, and the joint strip is thus deposited in the concrete, after which any surplus concrete is removed and the concrete finished in front and in rear of the joint strip 72 to produce the joint seen in Fig. 19. If desired, the joint strip 72 may be clamped between the blades 62 and forced down with the outstanding upper flanges of the blades come into contact with the surface of the concrete, the tamping action of said flanges will have a vibratory effect on the concrete, compacting the concrete on both sides of the joint. The members 62 thus serve as a combined tamper, joint holder and joint installer. After the joint material or strip has been forced into the concrete, the blades 62 are forced apart or separated slightly, so as to permit their withdrawal from the concrete, leaving the joint strip or material deposited in the concrete. The concrete will flow or may be worked against the joint strip progressively as the blades 62 are withdrawn, with either method of depositing the joint strip in the concrete. 95 Therefore, the spaces occupied by the blades 62 will be filled with concrete, leaving the joint strip deposited in the concrete true to alinement. The blades 62 may also be employed for installing contraction joint strips, and the joint strips may be installed so as to extend either completely or partially through the concrete. The device may also be employed for installing longitudinal as well as transverse joints.

The expansion joints are provided in the road at intervals to permit the road to expand longitudinally without buckling, the joints 72 being compressible or yieldable when extended entirely through the concrete.

Instead of depositing a premolded joint between the blades 62, a form may be used, as seen in Fig. 18, said form being of sheet metal and of U-shaped cross section which may extend partly or entirely through the concrete. The form may be deposited between the blades in the same manner as the joint strip 72, and the blades 62 then withdrawn and the concrete finished along the form. Afterthe concrete has set sufllciently the form may be withdrawn, and asphalt, a bituminous composition, or other filler poured into the space, to produce an expansion joint similar to 72 as seen in Fig. 19, or a contraction joint when the cut extends only partially through the concrete. It has been found in practice that it is desirable to depress the transverse joint strip flush with the top of the road by backing up the machine and lowering the screed directly over the transverse joint strip, so as to permit the entire weight of the screed to rest on the joint strip. The screed may then be reciprocated so as to depress the strip until the screed comes to rest on the side rails or forms, thereby bringing the joint strip flush with the surface of the road and also finishing the surface of the concrete at both sides of the joint.

Longitudinal joint depressing device A second longitudinal joint installing device (Figs. 1, 1A and 6) comprises a carriage l5 having wheels 76 movable on a pair of longitudinal rails 77, and the carriage hasrollers 78 movable under the rails toh'old the wheels 76 down on said rails. The rails 77 are secured at their ends to slides 79 movable vertically in .the frame 1 to enable said rails to be raised and lowered for purpose of adjustment and to lift the joint installing device off the. concrete. The slides 79 are adjusted by means of screws 80.

A roll 81 of paper, sheet metal or other suit-- able material is mounted on the frame 1 beyond the forward ends of the rails 77, and the strip 82 for producing the longitudinal joint passes rearwardly from the roll under the rails and is doubled transversely and forced down into the concrete to complete the longitudinal joint.

A strip folding and depressing tool 83 is pivoted at its forward end, as at 84, to the carriage to trail from said pivot, and is adapted to oscillate or vibrate in a longitudinal vertical plane. Said tool 83 has guide rollers 85 for the strip 82 and said tool moves over the strip. The tool 83 has downwardly converging sides, as seen in Fig. 6, to fold the strip 82 transversely with its edges folded upwardly, thereby doubling the strip on its longitudinal center line. The tool 83 has its lower edge inclined to depress the strip into the concrete, and said tool is also vibrated vertically to assist in forcing the strip down into the concrete. A plunger 86 is slidable in the carriage '75 to impinge on the tool 83, and is lifted by a spring 87. A lever 88 fulcrumed to the carriage 75 bears down on the plunger 86 to depress same, and is forced downwardly intermittently by cams 89 secured on a shaft 90 mounted in the carriage '75. A flywheel 91 is mounted on said shaft, and the shaft has a crank 92 for manually rotating same, although power may be used. Thus, when the shaft 90 is rotated the lever 88 is forced downwardly by the cams 89 to depress the plunger 86 and tool 83, and the lever 88 being released will result in the spring 8'7 raising the plunger 86 and lever 88. The downward blows or pressure'delivered to the tool 83 will assist in forcing the doubled strip down into the soft concrete into the portion thereof which has been prepared by the blade or bar 33 and blade 43, provided the strips in slot 330. are not used. A disk 93 carried by the carriage 75 in rear of the tool 83 completes the doubling of the strip 82 and the depression thereof into the concrete with the edges of the strip flush with or slightly below the surface of the concrete. The shaft 90 is connected by a sprocket chain 94 or other operative connection with the wheels '76 so as to propel the carriage 75 forwardly. The disk 93 may be used independently of the tool 83, and conversely said tool may be used independently of the disk.

Thus, with the frame 1 at rest after having advanced a distance less than the length of the rails 7'7, the strip 82 being unwound from the roll 81 so as to lay on the concrete below the rails, the shaft 90 is rotated to propel the carriage 75 forwardly on the rails 77, and the tool 83 moving on the strip, followed by the disk 93, will fold the strip and depress same into the concrete. Then, when the machine is advanced again, the carriage '75 will remain at rest while the rails 77 move forwardly, and the operation is repeated as before after the machine has advanced a predetermined distance. However, by omitting or removing the chain 94, the longitudinal joint installing device is operable to fold and force the strip 82 into the concrete during the forward movement of the machine.

The longitudinal joint depressing device is not used when the strips or material are delivered through the blade 33, and this joint depressing device is especially desirable in connection with the construction of concrete base courses of bituminous or asphaltic surface and other types of roads that are covered with flexible wearing coats of material. The experience has been that concrete'base courses ofthis type of road crack irregularly between the side edges, the same as plain concrete roads do, and these cracks in the base are reflected or induced through the bituminous or asphaltic surface layer of the road and add considerably to the destruction of the road, as well as adding considerably to the cost of maintenance. It has not been the practice to install joints in the concrete bases of roads of this type, because of the high cost involved, but with the present machine it is possible to install a longitudinal paper joint in the concrete base course at a low cost, and the bituminous or other surface layer may be applied subsequently.

Transverse contraction joint installing device The machine is equipped, in addition to means hereinbefore described, to install transverse contraction joints, and such device (Figs. 1A and 7) includes a T-iron or other suitable member 95 having depending pins or fingers 96 between which a strip 97 of rigid fibre, sheet metal or other suitable material may be inserted to be forced down into the concrete. The member 95 is movable vertically, being carried by screws 98 mounted in the frame 1.

By inserting the strip 9'7 between the fingers or pins 96, as seen in Fig. 1A, the member 95 may be depressed to force said strip down into the concrete, and the member 95 and strip may be of suitable form, either straight or angular, according to the type of contraction joint desired. A transverse channel may be out with the spader 58 to facilitate the installation of the joint strip 97.

Dowels 99 may be embedded in the concrete in advance of the screed 13, as will hereinafter more fully appear, and the strips 97 may be forced into the concrete above the dowels 99, so that when the concrete fractures below the strips 97, the slabs or sections of concrete will be tied together by the dowels or rods 99. The transverse breaking of the concrete may thus be controlled.

As shown in Fig. 11 the expansion joints 72 are installed at intervals of, for example, every two hundred feet, and between the expansion joints there may be a number of contraction joints 97. As shown, there are three contraction joints 97 between the expansion joints, so that the slabs will be approximately fifty feet in length. Fig. 11 shows the contraction joints 97 with the portions thereof adjacent to the edges or sides of the road and the longitudinal joint 82 at right angles thereto, and with the portions of said contraction joints intermediate the edges of the road and longitudinal joint 82 arranged obliquely so that the wheels of vehicles do not pass simultaneously over the contraction joints.

Fig. 11 also shows dowels 99 extending across the contraction joints, as well as transverse dowels 100 extending across the longitudinal joint. If desired, wire mesh reinforcing 101 may be embedded in the slabs to prevent fracturing thereof excepting along the longitudinal and transverse joints.

Fig. 1.2 shows the contraction joints 97 straight and at right angles to the side edges of the road and longitudinal joint, and the wire mesh 102 is embedded in the slabs and extends across the longitudinal joint to tie the slabs together, but does not extend across the expansion joints '72 or the contraction joints.

The transverse contraction joint installer may employ a mandrel blade 104 (Fig. 20) depending from the member 95, and the strip 97 bears against one side of the mandrel blade 104, and has its lower edge bent back, as at 105, to engage across the lower edge of the blade, so that the strip may be forced down into the concrete with the blade. The bent back lower edge portion 104 of the strip 97' will serve to anchor the strip in the concrete, as disclosed in my application Serial No. 149,442, filed November 19, 1926.

Floating device In rear of the joint installing devices is provided a floating device (Figs. 1A and 8) for smoothing off the surface of the concrete. The float, as shown, comprises upper and lower thin layers of wood or veneer 105 with a sheet of metal 106 between them, and said float is semiflexible so as to lay on the concrete with light pressure. The float is trailed from the machine by arms 107 which have pivot elements 108 movable in slots 109 of levers 110 fulcrumed in the frame 1 for reciprocation about longitudinal axes, so as to reciprocate the float transversely of the road. A bar 111 connects one lever 110 with an eccentric 112 on the shaft 20. Chains 113 are connected to the float and are engageable with hooks 114 on the frame, in order that the float maybe raised off the concrete and supported thereabove.

Longitudinal joint and edge finishing tools In rear of the floating device are tools 115 (Figs. 1A and 9) for finishing the longitudinal joint and side edges of the road. These tools are in the form of trowels to float on the concrete, and have longitudinal ribs 116 or other suitable means to move over the concrete and to round off the longitudinal edges or corners of the slabs, as seen in Fig. 9.

The tools 115 are pivoted to the downwardly and rearwardly extending arms of levers 117 which are fulcrumed to the frame 1, and the upper arm of each lever is disposed between coiled springs 118 disposed on a rod 119. A nut 120 is threaded on said rod to adjust the pressure of the springs 118 so as to hold the tool 115 with the desired pressure on the concrete.

Dowel placer In order to position the dowels 99 in the concrete a device as shown in Fig. 13 may be employed, including a bar 121 to extend across the rails 3 and having depending members 122 provided with slots 123 to receive the dowels. This device may be used for supporting the dowels in the desired position while the aggregate is poured between the rails 3, or the dowels may be forced down into the loose aggregate, and when the dowels are embedded in the aggregate, the bar 121 may be moved longitudinally to remove the members 122 from the dowels, after which the bar 121 may be removed from the rails. The rails 3 are preferably marked by chalk, or otherwise, to indicate where the dowels are located, so that the contraction joint may be properly placed over the dowels subsequently as the building of the road progresses.

Fig. 14 shows the dowels 99 fastened to parallel rods 124, and this mat may be embedded in the aggregate in advance of the screed 13. The contraction joint may then be formed over the dowels 99 between the rods 124, and said rods will serve to reinforce the slabs along the contraction joint.

Modified longitudinal joint installer Figs. 15 and 16 illustrate a device for separating the aggregate below the screed and simultaneously depositing a strip 82 in the concrete. The blade 33' is hollow for the passage of the strip 82' therethrough from a roll 81. The blade 33' has its forward end formed with a twist, as 90 at 125, from a horizontal to a vertical position rearwardly, and the blade is vertical in rear of said twisted portion to deposit the strip in a vertical position in the concrete. From the forward end of the twisted portion 125 a flat hollow guide 126 extends upwardly to guide the strip 82' downwardly, with the strip disposed transversely of the road so that it can move from the roll 81' and bend rearwardly into the line of the longitudinal joint. The strip moving through the twisted portion 125 is twisted from a horizontal to a vertical position and merges from the rear end of the blade 33' in a vertical position in the concrete. The blade 33 has the arms 34' and 34? at its front and rear ends, the front arm 34' being disposed in front of the guide 126 and twisted portion 125 to assist in separating the aggregate.

The rear portion of the blade 33' has an upper inlet opening 127 which communicates with the 110 spout 128 of a funnel 129 or other liquid container, in order that oil, tar, or other liquid or plastic material may be delivered into the rear portion of the blade 33 to coat the strip 82 before it merges from the blade and enters the con- 115 crete. It is also possible to deliver the liquid or plastic material from the rear end of the blade 33' into the concrete, without the strip, to provide the longitudinal joint, by separating the concrete, and causing it to break along the line 120 of the joint.

With this arrangement the strip 82' may enter the concrete with least resistance inasmuch as the strip enters the material from in front of the screed where the material is loose and not 125 compacted. The aggregate is thus screeded and packed over the blade 33' and strip 82', whereby the blade 33' will move forwardly with minimum friction.

Having thus described the invention, what is 130 claimed as new is:-

1. A road building machine including a frame, a screed, a. joint blade, and means on the frame for oscillating the screed forwardly and rearwardly over the blade.

2. A road building machine including a frame, a screed, and means on the frame for moving the opposite ends of the screed forwardly and rearwardly in opposite directions.

3. A road building machine including a frame, 4 a screed, means on the frame for reciprocating the screed longitudinally, and means on the frame for oscillating the screed forwardly and rearwardly.

4. A screed having openings in its forward portion and a pocket above the openings to receive surplus material, the rear portion of the screed being imperforate.

5. In a road building machine, a vibratins m screed, and joint producing means extending under the screed.

6. In a road building machine, a frame, a transverse reciprocating screed operably connected with a frame, a joint cutting blade and means for imparting vibratory blows to the screed and blade.

7. In a road building machine, a screed, and joint producing means extending under and forwardly beyond the screed and means for raising said first named means up and down to and from the plastic concrete.

8. In a road building machine, a screed, and a joint producing blade below the screed over which the screed is movable and means for raising and lowering both said screed and blade.

9. In a road building machine, a vibrating screed, a joint producing blade below the screed, and means for delivering material into and from the blade.

10. In a road building machine, a surfacing member, and a joint blade below and extending forwardly beyond said member and vibrated by said member.

11. In a road building machine, a surfacing member, and a joint blade below and extending rearwardly from said member and vibrated by said member.

12. In a road building machine, a surfacing member, and a joint blade below and extending forwardly beyond and rearwardly from said member and vibrated by said member.

13. In a road building machine, a vibrating surfacing membermovable transversely of the road, and a joint blade under said member and movable longitudinally of the road.

14. In a road building machine, a vibrating finishing member, and a joint installing member cooperable therewith.

15. In a road building machine, a vibrating finishing member, and a joint installing member carried thereby.

16. In a road building machine, a carriage, a tamper carried by the carriage, and a. joint cutting blade rigidly attached to the tamper substantially midway its end.

17. In a road building machine, a carriage, a surfacing member carried by the carriage for upward and downward movement, and a joint installing member associated with said member and mounted for upward and downward movement with the first named member.

18. In a road building machine, tamping means having joint installing means extending longitudinally thereof and means for clamping a joint strip to the first named means.

19. In a road building machine, tamping means having a depending joint installing blade extending longitudinally thereof and means for holding a joint strip.

20. In a road building machine, a transverse tamper, and a joint cutting blade carried under the tamper, the blade being disposed longitudinally.

21. In a road building machine, a transverse tamper, and a joint cutting blade associated with the tamper at its under surface.

22. A road building machine, comprising a frame, a joint cutting blade and a vibrating surfacing member. operating over the blade.

23. A road building machine, comprising a wheeled frame movable over a roadway under construction, a transverse reciprocating vibrated screed, a longitudinal joint cutting blade supported by the frame under the screed and vibrated by the screed while being moved longitudinally through the plastic concrete.

24. A road building machine, comprising a wheeled frame movable over a roadway under construction, a surfacing member bearing down onthe blade positioned-under the surfacer, means for raising the surfacer from the concrete, and means provided for automatically raising the blade simultaneously from the plastic concrete when the surfacer is raised.

25. A road building machine, comprising a frame, a surfacing member associated with the frame for up and down movement, a joint cutting blade positioned under the surfacer, and

means for producing hammer blows or vibrations to the surfacer, transmitting said vibrations to the blade, forcing the blade into the plastic concrete to separate the stone and coarser aggregate, producing a cleft in the concrete and compacting the plastic material adjacent to the blade.

26. A road building machine, comprising movable frame, spanning a roadway under construction, transverse surfacing member and yieldingly supported joint cutting blade positioned under the surfacer and means for movement of the surfacer and blade to and from the plastic concrete.

27. A road building machine, comprising a movable frame positioned over a roadway under construction, a blade associated with the frame and movable longitudinally of itself in the plastic concrete, a surfacer positioned over the blade to reciprocate forward and backward longitudinally of the blade-to compact and smooth the concrete adjacent to the blade.

28. A road building machine comprising a wheeled frame spanning a roadway under construction, a joint cutting blade associated with the frame to operate in plastic concrete, a surfacing member positioned over the blade, said surfacer having a receptacle on its upper surface to retain the surplus of mortar and openings in said surfacer through which said surplus mortar may be transmitted to the blade to be distributed on the surface as the surfacer and the machine are operated progressively as described in claim herein.

29. A road building machine, comprising a wheeled frame spanning a roadway, a surfacing member, means for reciprocating the member up and down to and from the plastic concrete, a joint cutting blade associated with the member to be forced into the concrete by the member and separating the coarse aggregate and producing a cleft in the plastic concrete.

30. A road building machine, comprising a wheeled frame spanning a roadway under construction, a transverse tamping member spanning the roadway, a longitudinal joint cutting blade associated with the tamping member for producing a cleft in the plastic concrete progressively as the tamper reciprocates up and down to and from the plastic concrete.

31. A road building machine, comprising a tubular joint installing blade associated with a frame spanning a surfacing structure, a surfacing member operating over a blade, a joint strip passing through the blade, means for supplying plastic or liquid material to the strip progressively as the strip passes through the blade.

32. A road building machine, comprising a frame to operate over plastic concrete, a blade drawn longitudinally through the plastic material, joint strip passing through the blade, and means for turning the strip to a vertical position progressively as the strip passes through the blade to be deposited in the plastic concrete in the rear of the blade.

, 33. The method which comprises forming pavements of plaster material having fine and coarse particles, displacing the coarser particles of the material transversely of a desired dividing line, finishing the surface of the material and causing finer portions of said material to enter the space previously occupied by the said coarser particles, and thereafter displacing at least a portion of the said finer portions while the material is plastic and inserting filling material in the said space.

34. The method which comprises forming pavements of plastic material having fine and. coarse particles, displacing the coarser particles of the material transversely of a desired dividing line, finishing the surface of the material and permitting finer portions of said material to enter the space previously occupied by the said coarser particles, forming a slot along the zone previously occupied by the displaced coarser particles, while the material is still plastic, and thereafter inserting the filling material in the slot.

35. The method which comprises forming a slot in concrete roadways during the process of building the same and before the material has become set, finishingthe surface of the material and permitting the slot to become refilled by said material, reforming the slot after the finishing operation and while the material is still plastic, and thereafter inserting a filling material in the slot.

36. The method of forming pavements of plastic material containing a mixture of fine and coarse particles, which comprises displacing the coarser particles from the vicinity of a given line and causing the said coarser particles to be replaced by the finer particles, and thereafter displacing the finer particles while the material is still plastic.

37. The method of forming pavements which comprises smoothing plastic concrete containing fine and coarse materials, slotting said concrete along a given line until the coarse material has been permanently displaced from said line, and finishing the surface over the line of the slot after completion of the slotting operation, and while the concrete is sufiiciently fluid to effect uniting of the cleft surfaces by the fine material.

38. The method of forming pavements which comprises alternately smoothing and cleaving plastic concrete containing fine and coarse materials until the coarse material has been permanently displaced, and finishing the surface over the line of cleavage after completion of the cleaving operation.

39. The method of forming pavements which comprises alternately smoothing and cleaving plastic concrete containing fine and coarse materials until the coarse material has been permanently displaced, and performing a smoothing operation on the surface of the concrete, in a direction across the line of the slot and for the full width of the pavement.

40. A road building machine comprising a frame to span a roadway under construction, joint producing means and laterally reciprocating surfacing means carried by the carriage to operate in plastic concrete, a cooperative means whereby said surfacing means and joint producing means are simultaneously raised from contact with the plastic concrete, and means for movement of the machine over the roadway.

41. A road building machine, comprising a carriage spanning a road under construction, laterally reciprocating surfacing means carried by the carriage to surface road materials, said surfacing means having longitudinal rigid aligning means mounted thereon, and vibrating means mounted over said aligning means, and means for actuating said vibrating means to cause vibrations to be transmitted to said aligning means whereby said vibrations are transmitted to said surfacing means to vibrate road materials underlying said surfacing means to compact said materials, and means for movement of the machine over the roadway.

42. A road building machine, comprising a carriage to span a road under construction, a transverse tamping member carried by the carriage to span the road and compact road mate rials, said tamping member having a smooth undersurface except at substantially midway of its ends, a joint cleaving implement projecting down below the under-surface of said tamping member to progressively penetrate the road materials as the tamping member is reciprocated up and down to form a separation of the road material longitudinally along the line of a joint, and means for movement of the machine over the roadway.

43. The method of producing joints in a roadway under construction, consisting of spreading and surfacing material, moving a blade longitudinally through said material, simultaneously moving a joint strip into the road material longitudinally of the roadway while guided by said blade, and simultaneously coating the strip with a liquid material as the blade is moved from the strip.

44. A road building machine, comprising a frame spanning a road under construction, transversely reciprocating screeding means carried by the frame to surface road materials, and means for vibrating said screeding means progressively as said screeding means is reciprocated laterally of the roadway and as the machine is moved forwardly to surface and compact said materials.

JOHN N. HELTZEL.