US3820914A

US3820914A - Self contained mobile asphalt mixing and applying apparatus

Info

Publication number: US3820914A
Application number: US00288987A
Authority: US
Inventors: H Zimmerman
Original assignee: H Zimmerman
Current assignee: Barber Greene Co
Priority date: 1972-09-14
Filing date: 1972-09-14
Publication date: 1974-06-28
Anticipated expiration: 1991-06-28
Also published as: BR7307090D0; DE2346212A1; HK43777A; AU6918974A; FR2200409A1; CH593391A5; KE2778A; JPS4965628A; BE815770A; AU478692B2; GB1442829A; CA987665A

Abstract

A bituminous concrete mixing and applying apparatus is disclosed which is constructed in an entirely self-contained and mobile fashion whereby bituminous concrete can be mixed and applied at the job site. The apparatus comprises an elongated mobile frame, such as a truck frame, upon which storage compartments are disposed for separately storing aggregates such as sand, stone, gravel, and the like, as well as liquid bitumens, such as asphalt, tar, or the like. A conveyor means is provided beneath the storage compartments for the aggregates for conveying such aggregates out from the storage compartment through a metering device and into a heating and drying mechanism whereat the aggregates are heated, dried and agitated. The dry aggregates as well as the liquid bitumens which similarly have been heated are discharged into a discharge mechanism or hopper assembly disposed on the mobile frame whereat bituminous concrete is formed. This bituminous concrete is applied to an underlying road surface to provide a covering commonly termed macadam, blacktop, or asphalt, by means of a spreader mechanism which, in the preferred inventive embodiment, constitutes a heating chamber, a plurality of spreading auger conveyors, a vibrator, and a roller compactor. In essence, the instant invention constitutes a mobile bituminous concrete plant which can be sent directly to a job site to mix and apply the bituminous concrete.

Description

United States Patent [191 Zimmerman 1 June 28, 1974 1 SELF-CONTAINED MOBILE ASPHALT MIXING AND APPLYING APPARATUS Harold M. Zimmerman, R.D. No. 1, Ephrata, Pa. 17522 221 Filed: Sept. 14, 1972 21 Appl. No.: 288,987

[76] Inventor:

[52] US. Cl. 404/110, 259/157 Primary Examiner-Nile C. Byers, Jr. Attorney, Agent, or Firm1-lolman & Stern [57] ABSTRACT A bituminous concrete mixing and applying apparatus is disclosed which is constructed in an entirely selfcontained and mobile fashion whereby bituminous concrete can be mixed and applied at the job site. The apparatus comprises an elongated mobile frame, such as a truck frame, upon which storage compartments are disposed for separately storing aggregates such as sand, stone, gravel, and the like, as well as liquid bitumens, such as asphalt, tar, or the like. A conveyor means is provided beneath the storage compartments for the aggregates for conveying such aggregates out from the storage compartment through a metering device and into a heating and drying mechanism whereat the aggregates are heated, dried and agitated. The dry aggregates as well as the liquid bitumens which similarly have been heated are discharged into a discharge mechanism or hopper assembly disposed on the mobile frame. whereat bituminous concrete is formed. This bituminous concrete is applied to an underlying road surface to provide a covering commonly termed macadam, blacktop, or asphalt, by means of a spreader mechanism which, in the preferred inventive embodiment, constitutes a heating chamber, a plurality of spreading auger conveyors, a vibrator, and a roller compactor. In essence, the instant invention constitutes a mobile bituminous concrete plant which can be sent directly to a job site to mix and apply the bituminous concrete.

l9 Claims, 9 Drawing Figures PATENTEDJUNZBJQH SHEET 3 0F SELF-CONTAINED MOBILE ASPHALT MIXING AND APPLYING APPARATUS BACKGROUND OF THE INVENTION This invention generally relates to paving machines and particularly concerns a self-contained, mobile bituminous concrete mixing and applying apparatus for operation directly at a job site. Bituminous concrete, as this technical term is utilized herein, relates to a resilient road surfacing material commonly designated macadam, blacktop,-or asphalt, as distinguished from rigid Portland cement, concrete road surfaces having a Portland cement binder.

Numerous roadways are in existence today which, upon occasion, require the usual maintenance and repair or patching. For large maintenance jobs amounting to resurfacing of entire roadway sections, such maintenance can economically and feasibly be effected by large paving machines. For the smaller, relatively minor maintenance jobs amounting to patching and the like, it is not feasible to provide and transport heavy roadway building equipment to effect such maintenance.

As such, most road repair jobs are effected by hand. For example, a typical procedure is to load bituminous concrete on the back of a pick-up truck or other similar vehicle and then send a crew consisting of a number of men out to the road location whereat the repair is desired. The bituminous concrete is then physically shoveled into the hole or crack in the roadway to form a repair, the bituminous concrete subsequently being manually tamped into place to complete the repair.

This manual method has its obvious disadvantages. For example, 'not only must a multi-member crew be provided, but the crew would have to know beforehand the amount of material that would be needed for the particular job, since the bituminous concrete, once mixed and placed upon the vehicle, cannot be maintained in a pliable state for a long period. The shortness of time that pre-mixed bituminous concrete remains pliable also makes it difficult to effect a repair at a location remote from the mixing plant requiring a relatively long driving time to reach. Additional problems are encountered, particularly when attempting to do winter repairs work. In this respect, a hot bituminous concrete repair is, of course, preferable to a cold repair due to its better adhesion properties. Yet, such a hot repair cannot readily be utilized in winter months since the hot mixed bituminous concrete, assuming it is to be available, cannot be maintained at the elevated temperature on the truck for long. It is primarily for this reason that most winter roadway repairs utilize the cold method, which is wasteful and invariably necessitates additional subsequent repair work, since a cold repair does not stand up to wear or temperature variations as well as a hot repair.

Additionally, a pre-mixed bituminous concrete batch that is taken out to the repair job may be of the same high quality and/or consistency as bituminous concrete actually mixed at the job site.

SUMMARY OF THE INVENTION It should thus be apparent that a need exists in the road repair and resurfacing field by which the repair of roadways can be modernized and otherwise facilitated to thus eliminate the archaic manual methods now in use. It is the primary objective of the instant invention to provide an apparatus by which this need can be filled.

It is a further objective of the instant invention to provide a novel apparatus which can transport bituminous concrete ingredients in separate compartments to the job site, whereat the apparatus can automatically proportion, mix and apply bituminous concrete, thus assuring the provision of a consistent high quality bituminous concrete patch from job to job, without waste.

It is a further objective of the instant invention to provide a bituminous concrete mixing apparatus which is, in addition, capable of applying the mixed bituminous concrete automatically to the surface of the roadway to be repaired.

It is yet another objective of the instant invention to provide a bituminousconcrete mixing and applying apparatus which is entirely self-contained and which is mobile, which apparatus is capable of operation with a reduced crew, such as one man.

It is another objective of the instant invention to provide an improved self-contained bituminous concrete mixing apparatus by which a hot bituminous concrete repair can be effected at any time of the year, even during the winter months.

Still another objective of the instant invention is the provision of a novel improved bituminous concrete mixing and applying apparatus by which quality repair of roadways can be achieved at low cost.

These and other objects which will become apparent as the description proceeds are implemented by the novel invention, which, as aforestated, constitutes a self-contained mobile bituminous concrete mixing and applying apparatus. In the preferred inventive embodiment, the apparatus is disposed upon a mobile frame, such as a truck, and incorporates a plurality of separate compartments for separately storing the aggregates and liquid ingredients of a bituminous concrete mix. For example, separate compartments are provided for the storage of fine and coarse aggregates, as well as for the storage of liquid bitumen, such as asphalt itself.

The aggregates are removed from the storage compartments therefor at the job site through metering gates or the like which ensures a predetermined amount and ratio of the aggregates. The aggregates are then conveyed to a heating and drying mechanism also disposed on the mobile frame, which mechanism in the preferred inventive embodiment constitutes a rotatable heating and drying drum. The aggregates are dried and are raised to a temperature of approximately 400 F. in the rotating drum mechanism and are dropped into a hopper containing a further metering mechanism from which the ingredients are discharged into a pug mill type mixing conveyor. A liquid bitumen is added to the mixing conveyor, the bitumen being separately maintained in a separate storage compartment which may be heated. The amount of dry aggregates vis-a-vis the liquid bitumen is carefully controlled by means of the metering mechanism associated with the hopper and by means of a bitumen metering device. In this fashion, bituminous concrete is provided having controlled consistency and quality.

The bituminous concrete, i.e., the mixture of the aggregates and the bitumen, is then fed into a spreader mechanism preferably carried behind the mobile frame by which the bituminous concrete is applied to the surface of an underlying roadway. In the preferred inventive embodiment, the spreader mechanism constitutes a forwardly disposed heating chamber so as to heat the underlying road surface thereby assuring good adhesion for the bituminous concrete. A plurality of auger conveyors are also provided for evenly distributing the bituminous concrete over the underlying and heated surface. The distributed bituminous concrete is then settled by means of a vibrating mechanism and finally is compacted by a roller rearwardly disposed on the spreading mechanism.

The combination bituminous concrete mixing and spreading apparatus generally described above separately stores all the ingredients of the bituminous concrete so that the problems associated with premature hardening of a pre-mixed batch are entirely eliminated. Further, a predetermined amount of bituminous concrete having a controlled consistency and quality is mixed at the job site through the utilization of the apparatus of the instant invention, therefore eliminating the prior art problems of predetermining the amount of bituminous concrete that will be needed for any given job. The repair effected by the machine of the instant invention can utilize the hot technique even during winter months and, importantly, operation of the apparatus of the instant invention can be effected by one man, if so desired.

BRIEF DESCRIPTION OF THE DRAWINGS The invention itself will be better understood and additional features and advantages thereof will become apparent from the following detailed description of one preferred inventive embodiment, such description making reference to the appended sheets of drawings, wherein:

FIG. 1 is a side elevational view of a truck constructed to incorporate the self-contained bituminous concrete mixing apparatus of the instant invention;

FIG. 2 is a top plan view of the bituminous concrete apparatus of FIG. 1;

FIG. 3 is a side elevational view of the apparatus of FIG. 1 partially broken away and in cross-section for illustrative clarity;

FIG. 4 is a front elevational view of the apparatus of FIG. 3 takenalong lines 44 thereof;

FIG. 5 is an elevational view in section of the apparadepicted in FIGS. 1 and 3 of the drawings; and

FIG. 9 is an elevational view, in section for clarity, of thelauger or spreading conveyor of the bituminous concrete spreading apparatus depicted in FIG. 8, taken along lines 99 thereof.

DETAILED DESCRIPTION OF A PREFERRED INVENTIVE EMBODIMENT Referring now to the drawings, and particularly to FIG. 1 thereof, the novel bituminous concrete apparatus of the instant invention can be seen disposed upon the bed or mobile frame 20 of a truck generally designated by the reference numeral 22. The bituminous concrete apparatus comprises a first storage means generally designated by the reference numeral 24 for storing coarse and fine aggregates such as sand and gravel, and a second storage means generally designated by reference numeral 26 for storing liquid bitumen, such as liquid asphalt or tar. The aggregates within the first storage means 24 are removedand dispensed therefrom through a first metering means generally designated by reference numeral 28 (see FIG. 3) via a conveyor mechanism having a first substantially horizontal section generally designated by reference numeral 30 and a second substantially vertical section generally designated by reference numeral 32, into a heating and drying means generally designated by reference numeral 34 wherein the aggregates are dried and are raised to an elevated temperature and transported towards the rear or left-hand side of the apparatus as viewed in FIGS. 1 and 3. The aggregates are then dispensed into a hopper generally designated by reference numeral 36 containing a further metering mechanism from which the aggregates are discharged into a pug mill type mixing means 116 118 into which the bitumen is likewise metered so as to form bituminous concrete therein of controlled quality and consistency. The bituminous concrete so formed is then discharged into a spreading means generally designated by reference numeral 38 disposed rearwardly of the mobile frame, spreading means 38 depositing the bituminous concrete onto the surface of the underlying roadway so as to effect a proper repair of the roadway.

In the preferred inventive embodiment, the first storage means generally designated by reference numeral 24 comprises a plurality of separate compartments such as

compartments

40 and 42 as can best be seen from the top plan view of the apparatus depicted in FIG. 2. Each of the

compartments

40 and 42 define substantially rectilinear chambers with the

outside walls

44 and 46 thereof (see FIG. 5) being downwardly and inwardly inclined much in the manner of a hopper. Separate coarse and fine aggregates, such as sand and gravel or the like, are separately stored within each of the individual storage compartments 40 and 42. Loading takes place from the top of the compartments as shown in FIGS. 2 and 5.

The bottom sides of each of the

separate storage compartments

40 and 42 are open and are disposed immediately above an elongated substantially horizontal conveyor section generally designated 30, which conveyor 30 can, for example, comprise a belt conveyor driven in a clock-wise manner when viewing FIG. 3 by any suitable drive mechanism which has not been illustrated for purposes of illustrative clarity. In this respect, the drive mechanism 30 could be coupled via a gearing arrangement to the substantially vertically disposed conveyor section 32 to be described hereinbelow.

Due to this construction, the aggregates such as sand and gravel rest directly upon the surface of the horizontal conveyor section 30 and, in operation thereof, the aggregates are carried forwardly towards the front or right-hand side of the apparatus as viewed in FIGS. 1 and 3. The actual amount and the ratio of the various aggregates that are dispensed from the storage compartments 40 and 42 is controlled by a first metering means generally designatedby reference numeral 28. Attention is directed to FIG. 5 of the drawings wherein the detailed construction of the first metering means 28 can be seen. In the preferred inventive embodiment,

the first metering means 28 comprises vertically

slidable gates

48 and 50 respectively associated with

compartments

40 and 42. The vertically

slidable gates

48 and 50 are disposed within channels or guides 52 and the vertical position of the

respective'gates

48 and 50 and thus the degree or amount of opening of the gates can readily be controlled.

For example, and in the preferred inventive embodiment, each of the

gates

48 and 50 have a gear rack 54 associated therewith, each gear rack 54 being coupled to pinion gears 56 disposed on shafts 58 which can be rotated by the external hand wheels 60. It should further be noted that the shaft 58 of the control mechanism for gate 48 is a flexible shaft, though it should be appreciated by those skilled in the art that other control mechanisms could readily be substituted for that specifically depicted in FIG. 5 of the drawings.

Thus, through rotation of the individual hand wheels 60, the amount and ratio of the aggregates, such as sand and gravel, that is dispensed from the individual or

separate compartments

40 and 42 can volumetrically be controlled. I

The aggregates thus dispensed by the horizontal conveyor section 30 are discharged from conveyor section 30 into a trough or well 62 disposed forwardly of the apparatus. From this trough or well 62, the discharged aggregates are carried upwardly by the substantially vertical conveyor section 32. In the preferred inventive embodiment, conveyor section 32 comprises a bucket conveyor which incorporates a plurality of buckets such as designated by reference numeral 64 disposed upon a chain 66, the chain '66 and thus the conveyor section 32 being driven by a gearing arrangement 68 which may constitute a power-takeoff from the truck upon which the bituminous concrete apparatus is mounted. The conveyor section 32 therefore serves to lift and carry upwardly the aggregates dispensed into the trough or well 62 from the individual storage compartments 40 and 42. At the top of the conveyor 32, the lifted aggregates are discharged into an underlying auger or screw generally designated by reference numeral 70. The auger or screw 70 serves to carry the discharged ingredients rearwardly, i.e., from right to left when viewing FIGS. l and 3, for example, into a heating and drying means 34 whereat the aggregates are dried and are raised to an elevated temperature as will be further described. The auger or screw'70 can be driven directly from the conveyor 32 by means of a chain or belt drive 72 as is depicted in FIG. 4, the chain or belt 72 being disposed about an idler pulley 74 as is indicated. In the preferred inventive embodiment, the

constitute an elongated hollow drum 78, preferably constructed of steel and being reinforced with a plurality of ribs 80 which further extend into the interior of the hollow drum, and by a forwardly disposed crossbrace 82. The hollow drum 78 is rotatable and is journalled for rotation at its rearward end by a journal bearing generally designated by reference numeral 84. At the forward end of the elongated hollow drum 78, a shaft 86 is attached to the cross-brace 82, the shaft being journalled as at reference numeral 88 and being coupled for driving rotation to the idler pulley 74 of the substantially vertical conveyor section 32 by a chain or belt drive 90. Therefore, as the substantially vertical conveyor section 32 is operated, rotation of the elongated hollow drum 78 is effected.

Disposed at the rear end of the hollow rotating drum 78 is a heating source, such as a forced air oil burner generally designated by reference numeral 92. A

substantially vertical conveyor section 32 is covered by a shroud 76 and it should further be noted that conveyor section 32 makes a slightly acute angle with the vertical, i.e., leans towards the rear of the apparatus so as to facilitate discharge of the aggregates into the heating and drying means 34 and so as to facilitate the mechanical gearing and other coupling arrangements between the heating and drying means 34, as will be described.

The function of the heating and drying means 34 is to dry and to raise the temperature of the aggregates deposited therein to approximately 400 F. and further to convey or transport the aggregates towards the rear of the apparatus for subsequent discharge. To this end, the heating and drying means of the instant invention in the preferred embodiment thereof will be seen to source of air is coupled to the burner 92 by a line 94 as depicted in FIG. 7, which line runs to a blower 96 disposed on the side of the apparatus as is depicted in FIG. 1. A non-illustrated oil line for supplying the burner 92 is coupled to an oil tank 98 also disposed on the mobile frame or bed 20 of the truck 22. Of course, fuel other than oil can be utilized to effect operation of the burner 92. The heated air from the heating mechanism or burner 92 passes through the hollow rotating drum 78 from the rear towards the front thereof, the rotation of the drum particularly in conjunction with the protruding vanes or fins serving to agitate the aggregates so as to effect a more even heating thereof and serving to transport or convey the aggregates from the front of the drum towards the rear thereof. To this end, and so as to assist in this transport process, it should be noted that the hollow drum 78 is not disposed exactly on the horizontal in the preferred inventive embodiment, but is slightly inclined from front to rear to effectively make a right angle with the substantially vertical conveyor section 32.

The hot air blown into the rotating drum 78 is discharged through an air channel means 100 communicating between the hollow drum 78 and each of the storage compartments 40 and 42. The air channel means 100 is partially formed by internal duct work leading to each of the storage compartments 40 and 42 and is further formed by a shroud or cover 102 which runs the length of the elongated hollow drum 78 and is disposed immediately above. Air flow into the drum 78 therefore follows arrow 104 as can best be seen in FIG. 3 into each of the storage compartments 40 and 42, which air flow serves to pre-dry the ingredients in the compartments and settles any dust that may occur through operation of the rotating drum 78. This air flow can be further assisted by the provision of fans 106 in the channel means communicating between each of the

compartments

40 and 42 and the hollow rotating drum 78. The drive for each of the fans 106 can be taken off the various gears provided for the substantially vertical conveyor 32 which, as has been described, is itself driven from the power takeoff 68 of the truck.

The now-heated aggregates moving rearwardly through the hollow rotating drum 78 are discharged therefrom through an outlet 108 provided at the rear end thereof into a hopper assembly 36 as can best be seen from a review of FIGS. 1, 3, and 7. The aggregates discharged into the hopper assembly 36 are dispensed or metered therefrom by the provision of a further gate 110 in association with a rotating drum or conveyor 112 which is contemplated to rotate in a clock-wise direction as appears in FIG. 7. Thus, the heated aggregates discharged into the hopper assembly onto the rotating conveyor 112 are dispensed from the hopper assembly through the slidable gate 110, whereby the aggregates fall down a chute 114 into a pug mill type mixing means defined by a funnel mechanism 116 and an underlying lateral conveyor or auger 118 to be described hereinbelow. Also discharged into the funnel mechanism 116 and thereafter into the lateral conveyor 118 is the liquid bitumen which has been stored -in storage compartment 26 and discharged through a pipe 120 through a metering valve 122 as can be seen in FIG. 7. Further, the liquid bitumen within the storage compartment or tank 26 may likewise have been raised to an elevated temperature through the provision of a further oil burner 124 which is fueled from the general supply tank 98.

The ratio of the dry ingredients to the liquid ingredi' ents discharged into the lateral conveyor or auger 118 can closely be controlled whereby the consistency and quality of the asphalt formed can be selected. In this respect, is should be noted that the hopper assembly and underlying rotating wheel or drum 112 are mounted on a pivotally disposed and spring-loaded lever or support arm 124. Specifically, the support arm 124 is pivoted to the truck frame around bearing 126 and the other end of support arm 124 is coupled to the body of the truck by a spring mechanism 128. In this fashion, the entire hopper assembly will move downwardly as aggregates accumulate therein, and, when empty, the hopper assembly would move upwardly, must as is shown in FIG. 7. This movement of the hopper assembly and specifically of the lever or support arm 124 can be monitored as an indication of the amount of aggregates discharged from the heater and drying means 34. To this end, it should be noted that operation of the rotating conveyor 112 is effected by an electric motor 130 which itself is controlled through mechanical linkage generally designated by reference numeral 132 coupled to the lever arm 124. Thus, as the lever arm 124 swings downwardly, i.e., counterclockwise about its pivot 126 when viewing FIG. 7, the electric motor 130 will be turned on by the linkage means 132. Similarly, when the hopper assembly is empty, the electric motor 130 will be turned off, thus effecting a selective control over the rotation of the conveyor 112.

The metering means or valve 122 disposed in the line 120 through which the liquid bitumen is discharged is likewise controlled via the mechanical linkage 132 by the position of the support or lever arm 124. Thus, when the conveyor 112 is in operation effecting discharge of aggregates down the chute 114 into the funnel 116, a controlled amount of liquid bitumen is likewise being dispensed or metered into the funnel 116. Additional control over the quality and consistency of the bituminous concrete being produced can be effected by operation of the gate 110 controlling the volume amount of aggregates dispensed, as has been mentioned above. Of course, and as should be apparent to those skilled in the art, various other synchronization mechanisms can be utilized in place of the mechanical linkage 132 so as to control the aggregates and liquid bitumen dispensed into the funnel 116.

The ingredients dispensed into funnel 116, both wet and dry, are mixed in the lateral conveyor or auger 118 to thereby form what is termed herein bituminous concrete. Of course, it should be appreciated that the operation of the apparatus as abovedescribed can essentially be continuous until the supply of bituminous concrete can be produced so as to fit the requirements of the particular job at hand. From the lateral auger or conveyor 118, the bituminous concrete is dispensed into a spreading means 38 disposed at the rear of the mobile frame 30 and carried along behind.

The spreading means or aparatus 38 comprises a heat chamber means 134 disposed forwardly of the mechanism to which is coupled an additional oil burner or other heater 136, also fueled from the fuel supply tank 98. In this fashion,.the surface of a roadway underlying the spreading means or mechanism 38 can be heated. In the preferred inventive embodiment, two such burners or heaters 136 are provided to either side of the ap paratus as can best be seen from a review of FIG. 8.

The lateral conveyor means generally designated by reference numeral 138 is disposed rearwardly of the heat chamber means 134 for receiving the bituminous concrete from the lateral auger or screw conveyor 118 and for evenly distributing the bituminous concrete over the heated underlying road surface. The detailed construction of the lateral conveyor means 138 is best illustrated in FIG. 9 of the appended drawings, the lateral conveyor means comprising in the preferred embodiment two

elongated augers

140 and 142 disposed one above the other, with auger 144 conveying the bituminous concrete outwardly towards either side of the apparatus and with auger 142 conveying the bituminous concrete inwardly from either side of the apparatus towards the center thereof. In this fashion, the even distribution of the bituminous concrete over the underlying roadway is assured.

A vibrator means generally designated by reference numeral 146 is disposed rearwardly of the conveyor means 138 for settling the distributed bituminous concrete. Specifically, and in the preferred inventive embodiment, the vibrating means 146 will be seen to comprise a triangularly shaped plate defining an inner chamber, to which plate a vibrator 150 is attached. It should further be noted that a hollow tube or duct 152 communicates between the interior of the heat chamber means 134 and the vibrator chamber 146 so as to further heat the bituminous concrete being settled, thus further assuring good adhesion properties and preventing the bituminous concrete from sticking to the chamber. The plate 148 of the vibrating means 146 is preferably hingeably mounted such as at pivot point 152.

A compacting means generally designated by reference numeral 154 is disposed at the rear of the spreader means 38 for compacting the now settled bituminous concrete. In the preferred inventive embodiment, the compacting means 154 constitutes a weighted roller, as is shown'.

The spreader means 38, or perhaps more accurately the mechanism for actually applying the bituminous concrete to the underlying roadway, is attached to the rear of the truck 22 by mounting means generally designated by reference numeral 156. In the preferred inventive embodiment, such mounting means constitutes a triangular mount defined by three hydraulic cylinders. In the preferred inventive embodiment, a cylinder such a cylinder 158 is disposed to either side of the spreader apparatus 38. In addition a cylinder such as cylinder 160 is disposed centrally of the spreading apparatus 38, the hydraulic cylinders coupling the spreader apparatus to the mobile frame 20 of the truck 22 in a fashion such that the height of the spreader means 38 above the ground as well as its angle relative to the underlying ground surface can readily be controlled. Of course, the rear of the spreader means 38 is supported by virtue of the compacting means or roller 154.

For illustrative clarity, a number of details of construction of the instant invention have not been illustrated in the drawings, though the fabrication of same can readily be effected by those skilled in the art. For example, each of the various burners or heaters provided are contemplated to have associated therewith electrical temperature sensors so that the temperatures thereof can carefully be controlled. Further, the positioning of the various metering gatesabove-described can be controlled through various well-known hydraulic means and, to this end, the novel invention is contemplated to include, if desired, hydraulic pump and suitable automatic controls therefor coupled to the power takeoff of the truck. Similar automatic controls and gearing can be provided to control the relative speeds of the various conveyors and the like so that the entire operation of the bituminous concrete producing apparatus can be automated.

Having now described in detail the preferred constructional features of the instant invention, a brief summary of the salient features thereof herein will prove to be helpful in coalescing the understanding thereof of a person of ordinary skill in this art. The novel invention has been seen to comprise a selfcontained mixing apparatus which is disposed upon an elongated mobile frame such as a truck body. Separate storage compartments are disposed on the frame for separately storing the aggregates and the liquid bitumen. A conveyor means is provided for conveying the aggregates from the various storage compartments therefor forwardly to the front end of the mobile frame,

and upwardly from the front end of the frame into a heater and drying means for heating and drying the aggregates which is disposed above the storage compartments along subsantially the length of the frame. The heater and drying means incorporates an agitator means or vanes serving to move the aggregates heated therein from the front of the frame to the' rear thereof, whereat the heated agregates are discharged into a discharge means disposed at the rear of the frame. The heated aggregates are now dropped downwardly into a mixing means into which the liquid bitumen is also dispensed, the amount of ingredients dispensed into the mixing means being carefully controlled and metered so as to form bituminous concrete. In the preferred inventive embodiment, this bituminous concrete is then spread and applied to the underlying roadway by means of a separate, though associated, apparatus which serves to first heat the underlying roadway, spread the bituminous concrete, settle the bituminous concrete, and compact same. The entire apparatus, as abovestated, is mobile and can readily be transported to the scene or site of a repair job, and operation of the apparatus can readily be effected by a minimum crew, thus resolving many problems that have faced the prior art.

It should be apparent from the foregoing detailed description that the objects set forth hereinabove have been successfully achieved. Moreover, while there has been shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims. Accordingly,

What is claimed is:

1. A self-contained bituminous concrete mixing apparatus comprising, in combination:

an elongated mobile frame;

a plurality of storage compartments disposed on said frame for separately storing aggregate and liquid bitumen;

an elongated hollow rotatable drum and a burner therefor disposed on said frame and defining means for heating and drying the aggregates, said drum being provided with agitator means therein for moving aggregates through the drum from one end thereof to the other during rotation of said drum;

means for effecting rotation of said drum;

conveyormeans disposed on said frame adjacent said aggregate storage compartment for transporting aggregates from said compartment into said one end of said hollow drum;

receiving means disposed on said frame adjacent said other end of said hollow drum for receiving the heated and dried aggregates from said hollow drum and for discharging same; mixing means disposed on said frame beneath said receiving means into which is discharged the heated and dried aggregates; and

means coupled to said liquid bitumin storage compartment for discharging liquid bitumen into said mixing means;

said mixing means effecting a mixing of the aggregates with the liquid bitumen to therein form bituminou's concrete.

2. An apparatus as defined in claim 1, wherein a plurality of compartments are provided for separately storing a plurality of different aggregates, and wherein metering means are operatively associated with said compartments so as to discharge to said conveyor means predetermined amount and ratio of said different aggregates.

3. An apparatus as defined in claim 2, wherein the ag gregates are coarse and fine, said apparatus further including an additional heater means for maintaining the bitumen within said storage compartment therefor at an elevated temperature.

4. An apparatus as defined in claim 1, wherein said burner is disposed at an end of said drum, and wherein said drum is tilted from front to rear whereby the aggregates within the drum are more readily moved from the front of the drum to the rear thereof.

5. An apparatus as defined in claim 4, further including a spreader means for spreading and compacting the bituminous concrete on a road surface.

6. An apparatus as defined in claim 1, wherein said storage compartments include a plurality of separate chambers for separately storing aggregates disposed substantially along the length of the frame in a location to either side of and substantially immediately below said hollow drum defining said heater means, said conveyor means including an elongated substantially horizontal section disposed immediately below said separate chambers for feeding the aggregates therein in a direction toward the front of said mobile frame, and controllable gate means in association with said horizontal section of said conveyor to meter the amount of aggregates removed from each of said separate chambers.

7. An apparatus as defined in claim 6, wherein said conveyor means further includes a vertical section defined by a bucket conveyor for carrying aggregates discharged by said horizontal section upwardly and into said hollow drum.

8. An apparatus as defined in claim 1, wherein said burner associated with said hollow drum defining said heater means is a forced air burner effecting a flow of heated air through said hollow drum and about the aggregates therein.

9. An apparatus as defined in claim 8, further including air channel means communicating between said hollow drumand each of said storage compartments for storing the aggregates for effecting flow of air from said drum into said storage compartments whereby the aggregates within said storage compartments are further dried and whereby dust within said storage compartments is settled.

10. An apparatus as defined in claim 9, further including an additional blower means disposed in said air channel means, said additional blower means aiding the air flow into said storage compartments for storing the aggregates.

11. An apparatus as defined in claim 1, wherein said receiving means includes a hopper for receiving the heated aggregates from said drum, and a first dispensing means for controlling the amount of aggregates discharged from said hopper into said mixing means, wherein a second dispensing means is provided for controlling the amount of liquid bitumen discharged from said storage compartment therefor into said mixing means, and wherein means are provided to synchronize said first and second dispensing means.

12. An apparatus as defined in claim 1 1, wherein said mixing means comprises an auger conveyor.

13. An apparatus as defined in claim 11, wherein said first dispensing means comprises a conveyor disposed at the bottom of said hopper for carrying aggregates therein towards a discharge point whereat metering gates are provided, the speed of said conveyor, the closure of said gates, and the amount of liquid bitumen discharged by said second dispensing means being correlated.

14. An apparatus as defined in claim 13, wherein said synchronizing means includes means to sense the weight of the aggregates within said hopper to control operation of said rotary conveyor and said second dispensing means.

15. A mobile apparatus for applying bituminous concrete to an underlying road surface, said apparatus comprising, in combination:

heat chamber means disposed forwardly of said apparatus for heating the underlying road surface;

lateral conveyor means disposed rearwardly of said heat chamber means for receiving bituminous concrete and evenly distributing same over the heated underlying surface;

hopper means disposed over and in feeding relation to said lateral conveyor for receiving bituminous concrete from some external source;

vibrator means disposed rearwardly of said conveyor means for settling the distributed bituminous concrete;

compacting means disposed at the rear of said apparatus for compacting the settled bituminous concrete; and

mounting means disposed forwardly of said apparatus for attachment of said apparatus to a separate motorized vehicle.

16. An apparatus as defined in claim 15, further including means to heat said vibrator means.

17. An apparatus as defined in claim 16, wherein a heating duct is disposed from said heat chamber means to said vibrator means.

18. An apparatus as defined in claim 15, wherein said lateral conveyor means comprises two elongated augers disposed one above the other, one of said augers conveying the bituminous'concrete outwardly toward either side of the apparatus toward the center thereof.

19. An apparatus as defined in claim 18, wherein said compacting means comprises a roller, said roller supporting said apparatus on the underlying surface.

Claims

1. A self-contained bituminous concrete mixing apparatus comprising, in combination: an elongated mobile frame; a plurality of storage compartments disposed on said frame for separately storing aggregate and liquid bitumen; an elongated hollow rotatable drum and a burner therefor disposed on said frame and defining means for heating and drying the aggregates, said drum being provided with agitator means therein for moving aggregates through the drum from one end thereof to the other during rotation of said drum; means for effecting rotation of said drum; conveyor means disposed on said frame adjacent said aggregate storage compartment for transporting aggregates from said compartment into said one end of said hollow drum; receiving means disposed on said frame adjacent said other end of said hollow drum for receiving the heated and dried aggregates from said hollow drum and for discharging same; mixing means disposed on said frame beneath said receiving means into which is discharged the heated and dried aggregates; and means coupled to said liquid bitumin storage compartment for discharging liquid bitumen into said mixing means; said mixing means effecting a mixing of the aggregates with the liquid bitumen to therein form bituminous concrete.

3. An apparatus as defined in claim 2, wherein the aggregates are coarse and fine, said apparatus further including an additional heater means for maintaining the bitumen within said storage compartment therefor at an elevated temperature.

9. An apparatus as defined in claim 8, further including air channel means communicating between said hollow drum and each of said storage compartments for storing the aggregates for effecting flow of air from said drum into said storage compartments whereby the aggregates within said storage compartments are further dried and whereby dust within said storage compartments is settled.

12. An apparatus as defined in claim 11, wherein said mixing means comprises an auger conveyor.

15. A mobile apparatus for applying bituminous concrete to an underlying road surface, said apparatus comprising, in combination: heat chamber means disposed forwardly of said apparatus for heating the underlying road surface; lateral conveyor means disposed rearwardly of said heat chamber means for receiving bituminous concrete and evenly distributing same over the heated underlying surface; hopper means disposed over and in feeding relation to said lateral conveyor for receiving bituminous concrete from some external source; vibrator means disposed rearwardly of said conveyor means for settling the distributed bituminous concrete; compacting means disposed at the rear of said apparatus for compacting the settled bituminous concrete; and mounting means disposed forwardly of said apparatus for attachment of said apparatus to a separate motorized vehicle.

18. An apparatus as defined in claim 15, wherein said lateral conveyor means comprises two elongated augers disposed one above the other, one of said augers conveying the bituminous concrete outwardly toward either side of the apparatus toward the center thereof.