US2211933A

US2211933A - Road making machine

Info

Publication number: US2211933A
Application number: US123183A
Authority: US
Inventors: Madsen Martin
Original assignee: MADSEN IRON WORKS
Current assignee: MADSEN IRON WORKS
Priority date: 1937-01-30
Filing date: 1937-01-30
Publication date: 1940-08-20
Anticipated expiration: 1957-08-20

Description

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6 Sheets-Sheet 1 Aug. 20, 1940. M. MADsEN ROAD MAKING MACHINE Filed Jan. 50, 1937 lr//v/'zf/m IN VE NTOR ATTORN EY Aug. 20, 1940. M. MADsEN 2,211,933

ROAD MAKING MACHINE Filed Jan. 30, 1937 6 Sheets-Sheet 2 ATTORNEY Aug. 20, 1940. M MADSEN 2,211,933

ROAD MAKING MACHINE Filed Jan. 30, 1957 6 Sheets-Sheet 3` 'ATTORNEY 6 Sheets-Sheet 4 Filed Jan. 30, l1937 WNN Aug. zo; 1940. M. MADSEN 2,211,933

ROAD MAKING MACHINE Filed Jan. 30. 1937 6 Sheets-Sheet 5 ATTORNEY Aug. 20, 1940. M. MADsEN ROAD MAKING MACHINE Filed Jan.' 30. 1937 sheets-'Sheet 6 WAHM/WM5 INVENTOR v ATTORNEY U bm. x

Patented Aug. 20, 1940 UNITED STATES ROADI MAKING MACHINE Martin Madsen,

signor to Madsen Park, Calif., a

Application January 30,

14 Claims.

My invention relates to a power driven device h-aving utility in the construction or reconstruction of road surfaces, and relates in particular to a machine for making roads either from the materials present in the road surface previously existing, or from aggregate or surfacing materials which are obtained from other sources. This application is a continuation in part of my pending application Serial No. 645,499, led December o 3, 1932 for Method of and apparatus for producing miner-al aggregate road.

It is an object of the invention to provide a device adapted to be moved substantially continuously along a lane or line of travel .defining a road to be constructed or an existing road to be reconstructed, this device having means for picking up road surfacing materials and preparing the same for the formation of a suitable road surface, the materials after such preparation being discharged by the machine upon the surface structure on which the road surface is to be formed. It is an older practice to resurface an existing road surface by scarifying the same and then applying a coat of oil which is either left to soak into the materials which are toconstitute the road surface, or a layer of sand or gravel, or both, may be spread over the oil. Roads of this character are not very durable in View of the fact that the bonding eiect ofthe road oil or asphalt does not penetrate deeply.' Other methods of road surfacing or include the mixing of aggregate or surfacing materials at a plant situated at a more or less distance from the place of road construction, and the subsequent step of spreading the mixture or asphalt and aggregate m-aterial so that it may be rolled down to a finished ro-ad surface. My present invention provides a device which may be driven slowly along the road, or along the line or lane to be occupied by a road, this device having a mill into which surfacing materials picked up from the road are delivered so as to be therein mixed with a binder such as heavy road oil or asphalt and subsequently discharged at the rear of or behind the device as it moves along and in such position that it may be readily spread and rolled, as the case may be, to produce a road structure of relatively durable character, at a minimum cost and with a minimum expenditure of time, as compared to existing methods of ro-ad construction and reconstruction. The surfacing materials which are taken into the mixer may be obtained in several different ways. They may be produced by scarifying the surface of a road which is to be renished,

road construction Huntington Park, Calif., as-

Iron Works, Huntington corporation of California 1937, Serial N0. 123,183

(Cl. S34-40) so as to break up the materials constituting such road surface, or the materials may be brought from other locations and placed in continuous ridge-like mounds or windrows along the lane l which is to be traversed by my device. Regard- 5 less of the source of the materials, which may be produced in the manner suggested in the foregoing sentence, such materials are taken into the device as it moves continuously along, are mixed with a suitable binder, preferably a road oil or l0 asphalt, and after being thoroughly mixed with the binder are discharged so as to leave behind the device, and along the lane of travel thereof,

a continuous supply of road surfacing material in condition to be spread and rolled. In one pracl5 tice of my method of road construction, the existing roadway may be scaried so as to break the surface materials thereof into relatively small pieces, and to the aggregate material thereby produced other materials such as sand, gravel or 220 crushed rock may be added so that a more durable character of road surfacing materialis produced. The aggregate mass of material, consisting of the divided surface materials of the previously existing road structure and the added sand, gravel 25 or crushed rock are then formed into continuous ridge-like piles in substantially centralized position relative to the line of travel along which the device is to be driven. It is an object of my invention to provide, for receiving the aggrel30 gate materials as they are continuously picked up from the road surface, a mill having an effective, yet simple mixing means therein and means for delivering the binder to the materials Vjust prior to or during the time they are being mixed; '35 it being a further object of the invention to provide a simple and effective means for controlling the mixing action, this means operating to maintain the materials in the mixture for such length of time and under such back pressure that a `40 proper mixing and preparation thereof is assured.

It is a further object of the invention to provide a device of this character having ground engaging elements on the two sides thereof, and

means for adjustably and controllably support- 45 ing a member for picking up the materials from the road surface, this supporting means having or embodying an automatic device for vcompensation or independent vertical movement of the ground engaging element, so that tipping of the 50 member for picking up the materials of the road surface will be minimized.

It is a further object of the invention to provide a pick-up means, for taking the material from the ground surface and delivering the same 55 into the mill, this pick-up means having a hydraulic device for maintaining and controlling the position thereof, this hydraulic device having a pump member continuously pumping a supply of hydraulic fluid such as oil through a bypath, together with a control means for diverting the hydraulic fluid into the hydraulic chambers of the device, or releasing hydraulic fiuid from such chambers, as may be desired by the operator of the road making machine.

Itis a further object of the invention to provide a road making device of the general character hereinbefore described having adjustable guide means disposed at the forward end thereof for directing the aggregate material into the pickup means which is adapted to deliver such material into the mill, the adjustability of this guide means making it possible to adapt the same to the various conditions of operation which may be encountered, and assuring that the aggregate materials Will be always directed properly into the pick-up means of the road making device.

It is a further object of the invention to pr"- vide, in conjunction with the road making device, an improved means for feeding a binder to the materials which are to be mixed or which are being mixed in the mill. This improved binder means is so constructed that it will continuously feed the binder material as the road making cle-- vice is propelled forwardly and will automatically Vary the quantity of binder material in accordance with the change in speed of travel of the road making device. in addition to the foregoing it is an object of the invention to provide a binder feeding device having means whereby it may be adjusted so as to vary the quantity of binder material fed, while the road making device is in operation. For example, as the device is propelled forwardly the operator may observe that the sizes of the windrows of divided material change from time to time, and, without stopping the road making device, they vary the rate of speed of binder material in accordance with the rate at which the aggregate materials are fed into the mixer.

Further objects and advantages of the invention will be brought out in the following specication. i

Referring to the drawings which are for illustrative purposes only:

Fig. l is a side elevation of a preferred embodiment of my invention.

Fig. 2 is a rear end elevation, drawn to enlarged scale, of the device shown in Fig. l.

Fig. 3 is a section, to enlarge the scale, taken as indicated by the line 5-3 of Fig. l.

Fig. 4 is the plan view corresponding to Fig. i, but having the forward portion of the device broken away. i

Fig. 5 is a fragmentary plan view of the forward portion of the device, this view showing the guide members in divergent relation.

Fig. 6 is an enlarged fragmentary sectional view taken on line 6 6 in Fig. 5.

Fig. 7 is an enlarged sectional view taken as indicated by the line '1 -'i of Fig. 1.

Fig. 8 is a fragmentary section on a longitudinal vertical plane, showing the mixingmill of the device, means for delivery of aggregate materials into the mill, and means for controlling the Ydischarge of the prepared mixture from the mill.

Fig. 9 is an enlarged fragmentary sectional view taken on a plane indicated by the line 9 9 of Fig. 2, to show my novel oil feed lpump construction.

Fig. l0 is an enlarged section taken as indicated by the line lll-lil of Fig. l to show the vertically movable pivot means for the adjustable fulcrum links of the feed pump.

Fig. 11 is a partly sectioned schematic view showing the control for the hydraulic elevator for height adjustment of the device.

Referring to Figs. 1 to 4 of the drawings, the preferred embodiment of my invention disclosed therein includes a vehicle E5, preferably of automotive type. This vehicle embodies a body structure l5 including a longitudinal frame Il which may be fabricated from steel structural "rape and preferably includes a pair of spaced I-beams I8 which extend forwardly and rearwardly and slope downwardly at a slight angle in forward direction.

The vehicle i5 is provided with ground engaging means of movable or drivable character, such for example as wheels. Such ground engaging means are broadly referred to as tread elements l and are preferably of the general character of treads employed on caterpillar type tractors. The tread elements i5 are disposed at the sides of the body structure i6, and lie in vertical planes disposed to the sides of the longitudinal beams i3 of the frame il which forms the bed or supporting element of the body structure i6. Each of the tread elements l 9 includes a forward wheel 2E! and a rearward wheel 2l, supported at forward and rearward ends, respectively, of tread frame as that shown in Fig. l. Although these Wheels E@ and 2l might be permitted to run in direct engagement with the ground or road surface, it is preferable that they shall be made of such character that a continuous belt or chain 23, of the form ordinarily employed in caterpillar type of construction, may be mounted on each pair of wheels consisting of a forward wheel 2li and a rearward wheel r2l. To drive the tread belt 23, the rearward wheel 2l is provided with sprocket teeth, and teeth are provided for driving both the rear wheels 2l so that theyy in turn may drive the belt 223, whereby to propel the vehicle l5.

The rearward has a pair of oppositely extending shafts 2li such as shownin Fig. l, these shafts 2li rotatably supporting the rearward .wheels 2! of the tread element lil, and likewise supporting the rearward part of the body structure i6 ends of the tread frameY 22, the forward ends of the tread frames and likewise the forward ends of the tread elements l 9 being permitted to swing in vertical plane in accordance with accepted caterpillar tractor design. It will be understood that as the forward ments i9 pass over uneven road surfaces, they may move upwardly or downwardly in accordance with the surfaces over which they pass. As shown in Fig. 2, each rear Wheel 2l may have a sprocket 25 secured thereto in concentric rei lation to the shaft member 24 on which each wheel v2l is supported, these sprockets 25being adapted to engagement by drive chains 26 whereby the wheel 2l and the tread belt 23 may be driven, means being described herein, for driving these chains 26 at different speeds as may be required for steering of the vehicle, the same being under the control of the operator as the device is propelled along the line of travel defining or being defined by the position of a road to be formed or reformed.

The intermediate portion of the body structure I6 includes an engine housing 2'! to contain an portions of the tread eleprovided, as will be later engine 28, preferablyv of internal combustion type, the rearward end v2,9 of whichis shown in Figs. 1 and 4 projecting from the rearward end of the engine housing 21 so that drive means may be connected thereto. v y

As'shown in Fig. l the rearward or leftward portion of the frame I1 ofthe body structure Ylli includes av .platform structure 3l having a pair of structural channels 32 whi' h are tied together by cross-bracing means 33, this platform structure carrying an engine 34 which is mounted in laterally disposed relation and has a variable speed transmis-sion 35, best shownin Fig. 2, which connects to a shaft 35 with a variable speed and controllable tractor drive .and steeringl mechanism 31 which is shown only in elevation for the reason that it is of the type ordinarily employed in tractor design and is merely adapted to the needs of the present device. In cooperating relation to the tractor drive and steering mechanism 31 an operators platform 38 is mounted, this platform having a seat 39 which is offset leftwardly with relation to the vehicle l5 so that an operator seated thereon may readily see down the roadway ahead of the vehicle.y The operators platform 38 has lever and pedal means 40 and 4| thereon adapted to be moved by the operator so as to 'control the vehicle I5. On a sub-platform 43 which projects rightwardly from the frame I1 of the vehicle body I8, a feed pur'np 44 is mounted in such position thatit may bedriven from the engine 34, as will be hereinafter described.`

As best shown in Figs. 3 and 8, structural angles 45 are secured to the lower faces of the I-beams |18 and have the purpose of connecting to the frame l1 a bowl 46 forming part of a mixing mill 41. The bowl 48 includes a lower metal plate 48 having a bottom wall 49, the longitudinal edge portions of which 'curve upwardly and verge with vertical side walls 5!! which are lconnected to the downwardly extending legs of the angles 45. By means of screws 5I, longitudinally and centrally inthe bottom of the bowl '46. T-he front edge portion'53 of the. plate 48 which forms the bowl 46 is deformed in shape from its rounded effect shown as 54 to, a shape wherein a horizontal scraper or knife support 55 and a vertical wall portion 5tv are provided. From the vertical wall portions 55 vertical plates or aprons 51 are extended forwardly so as to form a mixing or earth loosening chamber 59, in front of the knife or scraper-.blade 58, the bottom of which is open, or as otherwise stated, the bottom of which is formed by the ground or road.' surface lying between 4the lower edges of the apron 51. The lower edges 51a of the aprons or walls 51 are formed horizontally as shown and have adjustable shoes 51h.

As best shown in Fig. c, an end wan se is disposed across the upper portion of the rearward end of the bowl 45, and the lower portion of the wall o-r plate 48 of the bowl 46 is provided with a notch Si so as to form a discharge opening for the rearward end of the mixing mill 41.` A feature of the invention is to provide'a means for producing a continuous back pressurev against the discharge of .mixed ma-terials from thebowl 46, regardless of whether the quantity of materials fed into the bowl is small or large, this back pressure being controllable so that the materials being mixed in the mill will bevcaused to ,pile up or accumulate in the rearward portion thereof, and such materials will bei thereby held in the a ridge bar 52 is secured I 53 in the closed position in which' it is shown in full line in Fig. 8.A

The mixing mill 41 has mixing means consisting of paddles 61 which are mounted on longitu- .dinal and substantially parallel shafts 58 supported by a rear bearing means 69 disposed to the rear of thewall El), and by a forward bearing means 1l) supported by means of brackets 1I in positions spaced forwardly of the blade 58 and within the forward portion of the chamber 59 defined by the aprons 51 so that loosening

blades

1,2 may be mounted on theshafts 68 within Athe chamber 59 and ahead of the blade 58, so that these loosening blades 12 may operate to loosen up the road materials which lie in the path of movement of the blade 58, before the blade 58 reaches the same, thereby materially facilitating the ease with which the pick-up means represented by the blade 58 and the mouth portion 53 of the bowl 46 may pick up these road materials and direct the same into the mill 41. The shafts 68 are rotated by the engine 21 through a train of gears 68a.

In accordance with my co-pending application hereinbefore mentioned, the blades 51 on each of the shafts `(i8 move upwardly in the center of the bowl 46. In other words, the left-hand shaft, looking at Fig. 3, rotates in anti-clockwise direction, and the right-hand shaft in this. gure rotates in clockwise direction. As clearly shown in Fig. 8, the blades 61 are sloped to force the materials which have entered the bowl 46 rearwardly toward the outlet opening 52, while at the same time thoroughly mixing these materials with an Vasphalt material, such, for example, as heavy road: oil, adapted to be fed to the materials to be mixed through an oil discharge member 14 disposed toward the forward end of the mixing y aggregate through delivery means, such, as the member 14, may be accurately and lautomatically controlled. For this purpose I have provided the oil feed pump 44 which is of the reciprocating and plunger type and preferably has two pistons as shown working in alternate relation. As shown in Fig. 4, this rfeed pump 44 has an oil inlet means 15 to which may be connected a hose 15 which extends rearwardly from the vehicle l5 to a tank wagon which is pulled along behind the vehicle, this tank wagon having means for heating the oil or asphalt if the same is required by the characteristics of the binder being employed. In some uses of my invention the binder employed may .be

ya road oil which will flow readily at normal tem' which piston rods 18 project forwardly to crossheads 'i3 to which walking beams or fulcrum levers are connected by pivot means 8| in positions to extend upwardly. Pivots 82 at the upper end of the fulcrum levers 80 are connected to connecting rods 83, the leftward or rearward ends of which engage the crank 80 of the laterally extending crank shaft |35 supported in bearings 86, this crank shaft 85 being driven by the engine 3ft through a shaft 01 and the reduction geai` means 30, the shaft 81 being connected through a universal coupling 89 with the transmission means 31 which is driven by the engine 30 through the shaft 35. Intermediate the ends thereof the i'ulcrum levers Sil are engaged by vertically adjustable pivots or fulcrurn means Q0 which, as shown in l0, comprise a vertically movable block 02 carried in a vertical slide 83 and having a vertical threaded opening 9d through which an adjustment screw passes. The block 82 has a pair of oppositely extending trunnions 98 to serve as pivots on which bodies 91 are turnable, the trunnions 00 having annular channels 9B therein engaged by screws 00 which project inwardly from the walls of the bodies 91 to prevent the bodies 91 from moving outwardly on the trunnions SIE. Each of the bodies 91 has a channel or opening |80 of rectangular crosssection in the outer portion thereof, and through each of these channels 80 a fulcrum lever 80 passes, as clearly shown in Fig. 10. Each body 91 forms a means for pivotally connecting the intermediate portion of a fulcrum lever 80 with a trunnion 06. When the crank shaft 85 is rotated, reciprocation is transmitted through the connecting rods 83 to the upper ends of the fulcrum levers 80, these-levers will be caused to swing on axes dened intermediate the ends thereof by the trunnions 35. Accordingly, if the trunnions 93 are positioned intermediate the lower and upper pivots 8i and 82 of the fulcrum levers 80, the cross-heads 10 and the pistons 11 associated therewith will be reciprocated back and forth the same distance as the upper ends of the fulcrum levers 80. But, should the block @il of the fulcrum means S0 be raised or lowered, the movement of the pistons 11 of the pump 44 will be respectively increased and decreased owing to the shift of the fulcrum points on which the fulcrum levers S0 swing. As previously herein indicated the block 92 of the fulcrum means 98 may be raised or lowered by means of the adjustment screw 95 Whichis under control of the operator occupying the rear platform of the vehicle I5.

The rearward part of the longitudinal frame I1 is pivotally supported around the shafts 20 which support the wheels 2|. The rearward part of this frame, therefore, is non-adjustable in height, In order that the mixing; mill 01 may pick up the road material in front of the blade 58 it is necessary that this mixing mill slope downwardly and forwardly so that the blade 58 is in proper position with respect to the read surface. In view of the fact that the mixing mill in the form of my invention shown herein is rigidly secured to the longitudinal frame i1, it is necessary to provide a means whereby the forward part of the longitudinal frame is vertically adjustable. This means I provide in the form of a hy lraulic means or hydraulic mechanism whereby an operator may raise or lower the forward end' of the longitudinal frame I1 and also the forward end of the mixing mill 41 in order to properly position the blade 58. Also incorporated in the hydraulic means is an equalzing means so that in the event an obstruction rides under one of the caterpillar treads there will be but a minimum disturbance to the proper operating position of the blade 58.

As shown best in Figs. l, 3, 4, and 11, this portion of my invention provides a pair of hydraulic piston and cylinder means |05, one of which is associated with the forward part of each tread frame 22 and one of the I-beams I8. Mounted at the forward end of each tread frame 22 are brackets |06 to which upwardly extending arms |01 are pivotally connected, the pairs of arms |01 being pivotally connected to a cross-bar |08. Pivoted to the central part of each cross-bar |08 is a block |09 to which a clevice ||0 is also pivotally connected, these parts |09 and I I0 constituting a universal joint. Extended upwardly from each clevice ||0 is a piston rod ||2 having a piston |I3 secured to the upper end thereof, each piston I I3 being positioned in a hydraulic cylinder ||4'. Each cylinder ||4 is rigidly mounted on a cross-beam ||6 which, as shown in Figs. l, 3, and 4, is supported by the I-beams I through the medium of interposed channels mixing mill 41,

the ground,

As shown best in Figs. 3 and 1l, my invention provides a liquid pump |20 which is mounted so as to be operated by the engine 34 at the rear of the road pug. This pump |20 draws liquid through a pipe I2| from a liquid sump |22 which is conveniently located on the apparatus adjacent the pump |20. Liquid under pressure is delivered by the pump |20 through a pipe |23. The pipe |23 is connected to a control valve |24 mounted on the Yforward platform |25 which is positioned directly ahead of the engine housing 21. The valve |24 has a valve body |26 providing a chamber |21 in which a valve member |28 is operable, this Valve member |28 being operated by a lever |29 accessible to an operator working on the platform |25. The valve body |26 has four communicating ports |30. |3I, |32, and |33. rlhe liquid pipe |23 is connected to the port |30, and the liquid pipe ||2 which is connected to the upper end of each of the hydraulic cylinders ||4 is connected by means of a branch pipe |34 to the port |3I. A return pipe |35 is connected to the port |32 and extends to the sump |22, while a return pipe |36 is connected to the port |33 and extends to the sump |22. ber I 28 is designed so that it has a diametral web |31 having closure formations |38 formed thereon, and. connected to the diametral web |31 is a tubular member |40 which extends to the inner cylindrical wall of the body |26 and forms The valve memmember |40 having a passage |4|. v

In the operation of the apparatus under description, sition shown in full lines in Fig. 3 the ,valve member |28 is positioned as shown in Fig. ,1.

The pump |20 is continuously operatedso that there is at all times a iiow of liquid from the sump |22 through the pipe |2| to the pump |20,\and from the pump |20 through the pipe |23 to the valve |24. When the parts are -positioned as shown this' liquid may flow through the passage |4|, the port pipe IIB is closed and thehydraulic system may be considered as locked. In other words,.whatever fluid is in the pump H9 and in the upper ends of the hydraulic cylinders H4 remains in 'these parts, and additional liquid cannot iiow into the system, nor can any of the liquid flow out of the system.

When the operator part of the frame and themixingmill, such 'as he may desire to do to accommodate irregularities V of the road, the operating lever |29 is moved in a clockwise direction, as shown in Fig. 3, which moves the valve member |23 into a position indicated by dotted lines |45 of Fig. 11. This, it will be seen, moves the passage Uil from communication with the port |32 and prevents escape of liquid therethrough. At the same time it vconnects the port |3| with the port |30V and the pump |20 therefore pump liquid through the pipe |34 into the pipe ||9 and delivers liquid to the 35 hydraulic cylinders ||4.

When the operator desires to lower the forward part of the longitudinalv frame and the forwardl part of the mixing mill the lever |20 is moved in an anti-clockwise direction in vorder to move the valve member |28 into a position which will communicate the port |3| with the port |32. This allows liquid to flow from the pipe H5 through the pipe turn pipe |35 to the sump |22.

For the purpose of controlling the rate of low- 55.-,ering of the forward part of the longitudinal frame |1 and the forward part of the mixing mill 41 I provide a check means Ain the form of a check valve |50 which has a valve member or ball |5| which is removed from its seat |52 when :.;the liquid is flowing into the pipe H9. V In other words, the fiow' oi liquid into the pipe H9 is unrestricted. However, a reverse ow through the check valve |50 seats the valve I5, but I provide a passage |53 closed by an adjustable needle ?.V |54 which may be opened to provide 'a slow reverse flow of liquid through this opening |53. This device is a precautionary means to prevent ar sudden lowering of the apparatus when the valve is moved into a position to communicate 7Q3the port |3| with the port |32.

The hydraulic mechanism just described, in addition to performing the usual functions of raising and lowering the forward parts of the apparatus in order to properly position the blade .75.;58, also acts as an equalizing means so that in the when the operating'lever isI in the po-:

|32, and be returned to 'the 'sump |22 through the return pipe |35. At this time the!` desires to raise the forward In viewV of the fact that the pump |20 is continuously operating,-

event one ofthe treads runs lover an obstruction or is in some manner raised from normal posiy tion there will be but a minimum of disturbance to the proper operating position of the blade 58. As previously pointed out, the rearward part of the longitudinal frame |1 is supported on the` shaft 24 which supports the, wheels 2 With the wheels 2| in proper position with respect to the road, the mixing bowl is also in a proper horizontal transverse operating position with respect to the road, and the only additional adjustment which is necessary is to raise or lower the blade 58 to a suitable position, thislatter function being performed by the hydraulic mechanism just described. The forward wheels 20, however, may raise or lower relative to the rear wheels 2|, this being possible since the front wheels are supported by the tread frames 22 which are free to raise vertically. When the forward wheel or the forward part of the caterpillar tread rides onto an obstruction the tread yframe 22 will pivot around the axis of rotation of the gear wheel |20. Ii there were a rigid connection between the forward part of the longitudinal frame I1 and the forward part of the tread frame 22, the result would be that the frame |1 would be tilted from proper transverse, horizontal position, and one end of the blade 58 would be raised relative to the other. However, in View of the hydraulic connection between the parts, the forward part of the tread frame .which has been raised may raise independently .of the longitudinal frame. When this occurs liquid under pressure is forced out of the hydraulic cylinder positioned thereabove, and this liquid flows through the pipe IIS-'to the hydraulic cylinder at the opposite side of the apparatus.` This, as is apparent, produces a slight raising of the forward part of the frame and after the obstruction is removed the parts autozur matically and immediately return to normal opl erating positions. However, due to the hydraulic connection the'mixing mill is not tilted from its proper operating position, and the only abnormal position which is' produced is the slight raisingr the forward part of each apron 51 is a mounting bracket |6| having a plurality of lugs |62 through which a rotatable adjusting screw |63 is extended. Threadedly mounted on the screw |63 islaA nut |64to which a pivot shaft |65 is pivotally connected on a transverse horizontal plane as indicated at |66.

of the related mold board |60. The mold board |50 may rotate around the shaft |65 as its center and may also swing around the pivot |66.

The pivot shaft |65 extends through a bracket |61 secured to the `outer sidek The upper end of the adjustment screw |14 extends to the exterior of the cylinder 1| and is provided with a wrench receiving portion |15 and also with an enlargement or collar |15 which engages the outer wall of a removable closure plate |11. Compressed between the closure plate |11 and the nut portion |13 of the sleeve |12 is a spring |18 conveniently located within the cylinder |1| as shown. By rotating the screw |14 the sleeve may be raised or lowered. Likewise, if a force is applied to the sleeve tending to raise it, and if this force is suiiicient to overcome the force of the spring |18, the sleeve and also the adjustment screw |14 may be bodily raised. The purpose of this function will be pointed out in the following description. Y

By rotating the adjustment screw |14 to raise or lower the sleeve |12 the mold board |90 may be swung around the pivot |96. In other words, the forward part of the mold board may be raised or lowered. By loosening the bolt |89, the mold board may be swung on the pivot |83 and in this way a pivoting of the mold board around the shaft |64 and the pivot |83 may be accomplished. In addition to the adjustment just referred to, the mold board may be swung around a vvertical pivot corresponding to the center of the vertical adjusting screw |63, and this is accomplished by means shown best in Figs. 5 and 6. Secured to the forward part of the longitudinal frame is a cross-member |92 having secured to the outer ends thereof an arcuate rack |93, there being one rack for each mold board construction. Each rack |93 is arcuated around one of the vertical adjusting shafts |65 as its center. For the purpose of supporting the forward end of the arms |10 my invention provides a bearing member |94 which, as shown in Fig. 6, is removably secured to the arm |10, such as by a machine screw l95, and which extends over a lower flange |96 of the member |92. 'I'his provides means whereby the arm may be swung on its pivot but at the same time supported so as not to place too great a strain on the bearing connection between the arm |10 and the vertical adjusting screw |63. Supported by the forward part of the arm |10 are bearings |91 supporting a shaft |98 carrying a worm |99 which engages with the arcuate rack |93. The end of the shaft |98 is designed to accommodate a wrench Whereby the worm |99 may be rotated in order to swing the arms around their pivots. In this way the entire mold board construction may be moved from a position extending outward as shown in Fig, 5 into a position extending substantially straight forward.

The mold board construction is so designed that it may be extended outwardly to provide the desired swath and so that the mold boards may also be raised, or lowered, or properly angled to accommodate any slope, crown, or curvature of road bed.

One of the features of the mold board construction, in addition to those just enumerated, is the fact that the forward part of the mold board may be raised bodily by compressing the spring |18, and this acts as a precautionary measure in the event some obstruction rides under the mold board. The various adjusting means are conveniently located and the operator may very readily and satisfactorily adjust the mold boards |60 to such positions that all of the road material may be directed into the mixing mill and therein mixed with `the road oil.

From the foregoing description it is believed that the operation of the apparatus of my invention and the method by which it performs its work will be readily understood. A brief description of its operation is substantially as follows.

The operator may first place the apparatus on the road where the material is to be picked up and mixed with road oil. then adjusted in height so that the blade 58 occupies a proper position relative to the road surface, this being done by proper operation of the lever |29 by the operator who is positioned on the platform |25. Also the mold boards |60 are properly positioned with respect to the road bed, being extended outwardly to cover the proper width, and being adjusted laterally and horizontally in order that the mold boards may fit the curvature or crown of the road bed or to extend horizontally in the event that there is no crown to the road bed. The feed pump 44 may also be adjusted to deliver approximately the volume of oil required, whereafter the apparatus is put into operation.` The operator at the rear of the apparatus handles the controls for both of the engines, clutches, brakes, the mixing pump for the road oil, and various other operations to be performed at that position. The operator on the platform |25 watches the oncoming road bed and windrow for irregularities and manipulates the hydraulic raising and lowering mechanism in order to keep the mold board and blade at their proper height. He may also watch the oil iiow and mixer feed condition and also give signals to the rear operator regarding speed and steering.

As the apparatus moves forwardly the mold boards direct the material into the forward compartment or mixing chamber 59 where it is engaged by the paddles 12. These paddles 12 tend to loosen the earth and to force it rearwardly over the blade 58. As the material passes over the blade 58 it is moved rearwardly not only by the material which follows it but also by paddles positioned along the shaft 68. At this time the feed pump 44 delivers road oil through the oil discharge 14 which drops onto the material being mixed by the paddles 12 at a point along the central longitudinal plane of the mixing mill. As the material passes rearwardly through the mixing mill it is continued to b-e mixed by the paddles 61, and, upon reaching the outlet opening 62, is thoroughly mixed.

I have found that it is quite essential to build up a back pressure on the material being mixed, in order that inter-granular friction within the surfacing may be produced, and I therefore provide an opening 62 designed to accommodate a minimum amount of material passing through the apparatus. As the material accumulates a back pressure is built up which, if it exceeds a predetermined value, forces the door 63 open, against the action of the weights 6. This places a back pressure on the material which is being mixed but at the same time provides a means whereby the apparatus will not be jammed or made inoperative due to the accumulation of too The mixing mill is.

more or less oil be required, the

great a load. As the pressure increases the door 63 is gradually opened so that as material enters the mixing mill in larger amounts and the volurne in the mill increases, larger amounts maybe discharged through the opening 62. As the material entering the mixing mill decreases the door 63 will return toward closed position, and the operation will be entirely automatic. In this way I am able to keep a suitable back pressure on the material regardless of the amount of material passing through the apparatus, and in this way the important advantages resulting from back pressure may be obtained even though the capacity varies materially.

The mixing action is the same as that which is produced in the mixing mill of my copending application referred to heretofore, the important advantage in the present construction being the maintaining of back pressure on the material Abeing Amixed even though the material is being passed through the mixing bowl in relatively small or relatively large amounts. As pointed out heretofore, the feed pump 44 is operated by the engine 34 which drives the apparatus, andtherefore its operation is correlated therewith. Should pump may be conveniently adjusted while the apparatus is in operation merely by rotating the adjustment screw 95, which has the effect of changing the lengths of the fulcrum levers 80.

During the moving of the apparatus along the road bed the operator on the platform |25 raises and lowers the forward part of the longitudinal frame in order to properly position the mold boards and the blade. Should the forward part of `either of the caterpillar treads be raised or lowered from normal operating position, the hyy draulic means will compensate for this change in position, as previously pointed out. i

I believe my invention to be broadly new and recognize that various alterations and modifications may be made without departing from the spirit and scope of my invention. I therefore do not wish my claims to be construedto limit the details of construction illustrated herein, but wish my invention to be broadly construed in accordance with the appended claims and to cover broadly the invention in its entirety as well as the several sub-combinations and elements which comprise the whole.

I claim as my invention: l

1. In a road making machine of the class described, the combination of a vehicle having rollable ground engaging means whereby the vehicle is movably supported on a supporting surface; a mixing mill carried by said vehicle having a material gathering blade, the mixing mill rearwardly of said blade having a bottom wall and side walls, and having side walls extending forwardly of said blade; shoes connected to the lower endges of said side walls so as to be adjusted vertically relative to the road surface traversed by said road making machine; and mold boards adjustably mounted ahead of said side walls.

2. In a road making machine of the class described, the combination of: a vehicle having rollable ground engaging means whereby the vehicle is movably supported on a supporting surface; a mixing mill carried by said vehicle having material mixing means therein, a blade for gathering from the surface material to be mixed, and discharging means for delivering mixed material to the surface; confining walls forming a chamber ahead of said mixing mill; shoes connected to the lower edges cf said confining walls so as to be adjustable vertically relative to the road surface over which said road making machine is driven; and a plurality of independent paddles operable in said chamber and above said 5l blade.

3. In a road making machine of the class de-n scribed, the combination of: a vehicle having i-:-A

rollable ground engagingmeans whereby the Vehicle is movably supported on a supporting sur- [10j face; a mixing fill carried by said vehicle having material mixing means therein, a blade for gathering from the surface material tobe mixed, and discharge means for delivering mixed material to the surface; crab-le in response to the pressure of the material in said mixing mill for holding back the movement of said material adjacent said discharge means.

andv adjustable means opl'lli 4. In a road making machine of the classrde- 2'0" sure means operable in response to the pressure 301 of the material in said mixing mill operatively s associated with said discharge opening.

5. In a road making machine of the class described, the combination of a vehicle having blade for 25,;

rollable ground engaging means whereby the ve- 35.1

hicle is movably supported on a supporting surface; a mixing mill carried by said vehicle hav-l ing material mixing means therein, a blade for gathering from the surface material to be mixed, and a discharge opening at said mixing millfor delivering mixed material from said mixing mill; a movable closure means for said discharge opening; and yieldable pressure applying means for holding said closure means in closed position.

6. In a road making machine of the class described, the combination of: a vehicle including a pair of rear wheel means and a pair of front wheel means; a mixing mill carried by said the rearward end of 40I vehicle and pivotally supported near said rear wheel means; a pair of hydraulic lifting means, one being operatively connected between each of said front wheel means and said mixing mill; and connecting means for connecting the cylinders of said hydraulic lifting means to provide a mixing mill carried by said connecting means for connecting the cylinders of said hydraulicl lifting means to provide equal iiuid pressure in each; andiiuid control means for delivering or withdrawing fluid to or from said hydraulic lifting means.

8. In a road making machine of the class described, the combination of: a vehicle adapted to be movably supported on a surface; a mixing mill supported by said vehicle having a blade adapted to gather material fromy said surface; and mold boards supported at the forward end "of said mixing mill and .disclosed the combination of:

for connecting ter described,

being adjustably conneoted thereto for bodily and angular relative movement to conform to the contour of said surface and to vary the swath of said apparatus. 9. In a mold board construction, for use as disclosed, the combination of a supporting structure; a mold board; rear connection means for pivotally connecting kthe rear part of said mold board to said supporting structure, and for raising or lowering same; and front connection means for connecting said mold board to said supporting structure for raising or lowering same or for pivoting same in a longitudinal plane.

10. In a mold board construction, for use as a supporting structure; a mold board; rear connection means for pivotally connecting the rear part of said mold board to said supporting structure, and for raising or lowering same; front connection means said mold board to said supporting structure for raising or lowering same or for pivoting same in a longitudinal plane; and means for laterally moving said front connection means. 11. In a road making machine of the characthe combination of a vehicle adapted to move along a road surface; a mixing mill caried by said vehicle to receive, mix, and discharge road material means for supplying a binder to the road material, said supplying means Iincluding a positive displacement pump having a drive means which is variable in its operation; movable means having connection with a ground engaging part of said vehicle so as to move in accordance with the rate of travel of said vehicle along said road surface; and an operative connection between said drive means and said movable means and acting to vary the operation of said drive means so that the feeding of binder to said road material will vary in accordance with the rate of. travel of said vehicle.

l2. In a road making machine of the character described, the combination of: a vehicle adapted to move along a road surface; a mixing mill carried by said vehicle to receive, mix, and discharge road material; means for supplying a binder to the road material, said supplying means including a pump having a moving wall to displace the binder; and means for varying the movement of said moving wall of said pump in accordance with the variation of the rate of travel of said vehicle along said road surface.

13. In a road making machine of the character described, the combination of: a vehicle adapted to move along a road surface; a mixing mill carried by said vehicle to receive, mix, and discharge road material; means for supplying a binder to the road material; means for propelling said vehicle over said surface; a moving part which varies in movement in accordance with the rate of travel of said vehicle; a ovv controlling connection between the said moving part and said supplying means operating to vary the supplying action of, said supplying means in proportion to the rate of travel of said vehicle; and means varying the action of said supplying means independently of the travel of said vehicle.

14. In a road making machine of the character described, the combination of: a vehicle adapted to move along a road surface; a mixing mill carried by said vehicle to receive, mix, and discharge road material; means for supplying a binder to the road material, said supplying means including a pump having a moving wall to displace the binder, means for varying the movement of said moving wall of said pump in accordance with the variation of the rate of travel of said vehicle along said road surface; and means varying the movement of said moving wall of said pump independently of the rate f travel of said vehicle.

MARTIN MADSEN. 0

A CERTIFICATE CE CORRECTION. Patent No. 2,211,955. August 2o, 19m.

MARTIN MADSEN.

It is hereby certified that error appears in the printed specification p of the above numbered patent requiring correction as follows: Page 6, second column, line 7l, for "weights 6" read --weights 66"; page 7, first column, -line 75, claim 2, for the word "discharging" read -discharge;

and second column, line ll, claim 5, for "fill" read quilland that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 10th day of December, A. D. 1914.0.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents.