US2772083A - Drier and mixer for fluent solid material - Google Patents
Drier and mixer for fluent solid material Download PDFInfo
- Publication number
- US2772083A US2772083A US415330A US41533054A US2772083A US 2772083 A US2772083 A US 2772083A US 415330 A US415330 A US 415330A US 41533054 A US41533054 A US 41533054A US 2772083 A US2772083 A US 2772083A
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- Prior art keywords
- drum
- solid material
- mixer
- drier
- ring
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Classifications
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C19/00—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
- E01C19/02—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for preparing the materials
- E01C19/05—Crushing, pulverising or disintegrating apparatus; Aggregate screening, cleaning, drying or heating apparatus; Dust-collecting arrangements specially adapted therefor
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C19/00—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
- E01C19/02—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for preparing the materials
- E01C19/10—Apparatus or plants for premixing or precoating aggregate or fillers with non-hydraulic binders, e.g. with bitumen, with resins, i.e. producing mixtures or coating aggregates otherwise than by penetrating or surface dressing; Apparatus for premixing non-hydraulic mixtures prior to placing or for reconditioning salvaged non-hydraulic compositions
- E01C19/1013—Plant characterised by the mode of operation or the construction of the mixing apparatus; Mixing apparatus
- E01C19/104—Mixing by means of movable members in a non-rotating mixing enclosure, e.g. stirrers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B11/00—Machines or apparatus for drying solid materials or objects with movement which is non-progressive
- F26B11/02—Machines or apparatus for drying solid materials or objects with movement which is non-progressive in moving drums or other mainly-closed receptacles
- F26B11/026—Arrangements for charging or discharging the materials to be dried, e.g. discharging by reversing drum rotation, using spiral-type inserts
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C19/00—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
- E01C19/02—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for preparing the materials
- E01C19/10—Apparatus or plants for premixing or precoating aggregate or fillers with non-hydraulic binders, e.g. with bitumen, with resins, i.e. producing mixtures or coating aggregates otherwise than by penetrating or surface dressing; Apparatus for premixing non-hydraulic mixtures prior to placing or for reconditioning salvaged non-hydraulic compositions
- E01C2019/1081—Details not otherwise provided for
- E01C2019/109—Mixing containers having a counter flow drum, i.e. the flow of material is opposite to the gas flow
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C19/00—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
- E01C19/02—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for preparing the materials
- E01C19/10—Apparatus or plants for premixing or precoating aggregate or fillers with non-hydraulic binders, e.g. with bitumen, with resins, i.e. producing mixtures or coating aggregates otherwise than by penetrating or surface dressing; Apparatus for premixing non-hydraulic mixtures prior to placing or for reconditioning salvaged non-hydraulic compositions
- E01C2019/1081—Details not otherwise provided for
- E01C2019/1095—Mixing containers having a parallel flow drum, i.e. the flow of material is parallel to the gas flow
Definitions
- the present invention relates to a: drier for fluent solid materials such as sand, gravel or broken stone, and to mixing plants including such driers.
- One object of the invention is to provide an improvedand efiicient drier of this character. Further objects are an improved feed means and improved discharge means for such a drier, and: a mobile drying and mixing plant of compact form including a drier for the purpose indicated.
- the drier of thisinvention comprises a drum of hollow elongated form which, in use, is mounted in inclined fashion for rotation about its axis thereby to forward the solid material through the interior of the drum, from the higher to the lower end, and through hot drying gas projected into the drum from the lower end, said drum having, at the higher end, an annular feed means rotatable therewith for introducing the solid material into the drum interior and, at the lower end, annular delivery means also rotatable with the drum for delivering the dried solid material to' a discharge device.
- the drying heat i derived from one or more burners arranged to project a flame and hot combustion gases into the cylinder, e. g. counter to, or in the direction of, the material flow.
- the feed means advantageously comprise a ring or wheel secured in collar fashion around the drier cylinder ring, this feedwheel having its rim formed to furnish a duct for solid material to be fed into the cylinder and having radial, or substantially radial blades for conducting the solid material under gravity from the duct to a corresponding admission opening into the cylinder.
- the use of a rotational series of such blades serves to divide the wheel up into a plurality of pockets which, in turn, supply the solid material to the cylinder as the former rotates, thereby giving a distributed feed.
- the delivery means are based on a similar principle-to the feedmeans, in that they comprise a ring or drumof larger diameter than the drier cylinder and rotate therewith, and in that they include scoops or blades'which serve toreceive and carry round the fluent material until it is transferred, under gravity, to the required point.
- the delivery means In the case of the delivery means, the supply of solid material is received from the cylinder itself, and the solid material is eventually delivered away from the cylinder.
- the delivery ring is arranged to form a means for storing, for later discharge, material supplied thereto from the cylinder in excess of immediate delivery requirements.
- Thedelivery and storage ring is advantageously adjoined and secured directly to the open lower end of the cylinder and has projecting thereinto, from the rear, the heating burner(s) and a batching or measuring device which can be. controlled so as to discharge measured quantities of the dried stone or the like to the point of use;
- the drier and. its feed and. delivery means referred to coupl'ed from this vehicle.
- a mobile plant for preparing bituminous mixtures for example tar mixtures or asphalts, such as are used in road making, as road dressings, and so on
- this plant also including equipment for melting the tar or like binder, a mixer proper for admixing the bitumen With the ballast solid material, and a common power ource for driving the various operating parts concerned, such as the rotating drier and the mixer.
- the plant can be mounted on a wheeled chassis having an engine which drives the cylinder and the paddles of the mixer.
- such a mobile plant can include a con.- veyor, driven for example from the. cylindenfor forwarding the moist, solid ballast ingredients of the mixture. to the drier via the feed means recited above.
- Figure l is a general side view of the plant.
- Figure 2 is a plan view of the same as seen in the direction of the arrows lI.ll in Figure l. I
- Figure 3 is a longitudinal cross section through the same on the line III-HI of FigureZ.
- Figure 4 is a front view of the plant seen in the direction of the arrow IV in Figure l and with parts broken away and in section.
- Figure 5 is a view from the opposite end in the direction of the arrows VV of. Figure 1, again with parts broken away and in section.
- the plant illustrated is mobile and in the form of av trailer vehiclewith a chassis 1 having longitudinal. sills, as at 2, cross bearers such as 3, road wheels '7, and a towing gear 4' terminating forwardly in a shackle. 5 and towbar attachment 6, whereby it can be coupled to the towing vehicle.
- the side arms of the towing gear 4 are pivoted to the sills 2' so that they can be raised for coupling to the towing vehicle or lowered on to the ground when the plant is to be used for longer periods in one place and un- In the latter event, supporting jacks are lowered at the forward and rear part of the plant, as indicated by the dotted chain lines 8, to maintain the chassis horizontal when the plant is so arrested.
- the towing gear 4 is shown in-the position it occupies when coupled to a towing vehicle.
- Power unit 9 This is generally denoted 9 in the drawings and comprises an encased internal combustion engine which is mounted on the right hand side of the plant. This unit serves to operate all the various moving parts of the plant, having for this purpose an output shaft 11 controlled by a clutch with a lever 10.
- the shaft 11 through a chain drive 12, operatesa first countershaft 13 for driving a supply pump in a bitumen kettle (see later) and also serving to drive, through a further chain transmission 14-, a second countershaft 15 which, inter alia, operates a fuel pump, the mixer, and the drying cylinder itself (all as will be later described).
- the output shaft is connected through a belt and pulley drive- 16 to a blower 17, with an air filter 18, for supplying combustion air to a drying burner.
- the Drier cylinder and ballast feed and delivery means consists of a cylindrical drum 19 which is furnished with a pair of annular collars 20 running on rotary bearings 21 carried on cross bearers of the vehicle chassis and, it will be noted, has its axis slightlyk inclined to the horizontal in the condition of use, i.'e. that illustrated in the drawings.
- the cylinder 19 is rotatable from a sprocket 22 carried by a stub shaft 23, driven from the countershaft 15'through a universal coupling 24, through a chain drive transmission 25, the chain passing around sprocket 22 and sprocket teeth 26 provided on the periphery of the cylinder 19.
- the main body of the cylinder is provided with a number of lifter plates 27 which are arranged to pick up the fluent solid ballast material, e. g. sand orgravel, to be dried by passage through the drum and subsequently mixed with the bitumen. and cascade it through the centre of the drum as the latter rotates and as the material gradually progresses from the higher to the lower end of this cylinder in counter flow to hot drying gases.
- the fluent solid ballast material e. g. sand orgravel
- a feed ring in the form of an external bucket wheel 28 which is open at its frusto-conical end 29 and serves to transfer solid aggregate, fed to the lower part thereof, to the interior of the cylinder 19. for drying passage 'therethrough.
- this feed ring 28 see particularly Figure 4, is divided into a number of pockets by radial partitions 30 which are connected between the circumferential wall of the feed ring 28 and the wall of the cylinder 19 at this part.
- a shorter but radial deflector plate 31 is connected to the cylinder 19 opposite each partition 30, this deflector plate 31 having an angled portion 32 whereby it is connected to the periphery 'of'the ring 28 and serving as a guide for introducing solid material into the feed channel between the two opposed walls 30 and 31 concerned.
- This channel leads to a rectangular opening 33 in the corresponding part of the cylinder wall, whereby as the cylinder 19 and its feed ring rotate, solid material received at the lower part of this ring is carried upwardly in the corresponding pocket in this ring, a part thereof passing into the channel 30, 31 for delivery to the interior of the cylinder 19 as this channel nears its upper position. Inthis way the amount of solid material fed into the drum is controlled.
- the solid material Onentering the drum, the solid material is picked up by shaped deflector plates 34, disoosed around the higher end of this cylinder so as to initiate its forward movement through the drum by conducting it at an early stage to the centre of the latter.
- a burner 38 mounted .in the plant so as to direct hot gases forwardly through the cylinder 19 from the rear end of the storage ring 35, is a burner 38 having a hood 39 to protect it from solid aggregate dropping through the A sealing ring 35 as mentioned above.
- This burner is provided with a torch rod 40 and is supplied with fuel under pressure, injected by the blower 17 from a fuel tank 41 through a supply line 42, incorporating a control tap 43 and having a bypass return 44 to the fuel tank, and with air from blower 17 through an air line 45 incorporating a pressure gauge 46 and a control valve 47.
- the hot gases from the burner 38 pass through the rearwardly flowing and cascaded solid material as it passes downwards through the cylinder 19, and these gases are eventually discharged through a chimney the lower part 48 of which surrounds the open forward end of the cylinder 19.
- This chimney 48 is provided with a hinged upper section 49 which can be lowered, as indicated in chain dotted lines in Figure 1, when the plant is travelling along a road.
- This device is provided at the rear side of the delivery and storage ring'35 and projects into the latter so as'to receive dried solid material therefrom and to conduct it in regulated quantity into the mixer of the plant.
- This batching chute comprises an inclined chute channel 51, the upper and lower ends of which are controlled respectively by a sliding cover 52 and a'pivoted door '53.
- This plate 52 and door 53 are operable from a common linkage in such a way that opening of one is accompanied by closure of the other and vice versa, thus precluding the discharge at any time of greater quantity of solid material than the capacity of this batching chute.
- the cover 52 which has its front part formed as a triangular deflector and its rear part as a flat plate,
- ' is movable by a pair of arms 54 articulated to the plate" portion and connected to levers 55 which are pivoted at their lower ends 56 and are rockable in common by means of a handle 57.
- Articulated to the levers 55 through links 58 are a pair of sector plates 59 between which the door 53 is carried.
- This mixer is mounted at the rear of the plant and serves for the mixing together of the dried aggregate material, batched thereinto as described above, and bituminous material in liquid condition to be supplied thereto from a bitumen kettle described hereunder.
- the mixer may be provided with heating means, as in the specific example under description, but this is an optional feature.
- the mixer comprises an opemtopped container 61 containing a pair of parallel shafts 62 and 63 each equipped with radial paddle blades 64 carrying heater tips 65 at their outer ends.
- the shaft 62 is operated through a chain drive 66 from the countershaft 15 and transmits the drive at its rear end through toothed gear wheels 67 to the other shaft 63.
- the solid aggregate material is poured from the batching device 50 into the upper end of the mixer chamber which is provided with a protective grid 68.
- a bitumen trough or bucket 69 Mounted above the right hand side of the casing 61 is a bitumen trough or bucket 69 which receives heated bitumen from the bitumen kettle (see below) and can be tipped by a handle 70 at appropriate times to pour into the mixer.
- This trough 69 is advantageously equipped with a bitumen-level gauge (not shown) to guide the user. 4
- the casing of this mixer is provided at its lower later l Parts with hollow jackets 71 which receive am ss hot air through ducting 72 and '73 from the bitumen heating kettle, thereby to keep the bitumen and the mixture warm. whilst the mixing operation is in progress.
- Exhaust chimneys 73 are provided for escape of' this hot air to atmosphere.
- the paddle mixer is furnished at its lower part with a door 74 which is operable through a linkage 75 by a handle 76 for the discharge from its bottom at prescribed times of a quantity of the asphalt or bituminous mixture.
- bitumen kettle and supply connections The bitumen kettle comprises a tank 79 which is supplied with bitumen from a barrel warming chamber Sillocated at the underside of the vehicle through a mesh screen (not shown).
- This bitumen includes a heater assembly, generally designated 81', supplied from a fuel tank 82 and serving to liquify this bitumen for delivery to the bitumen trough and paddle mixer.
- the kettle comprises a pump 83 which is driven through a belt 34 from the countershaft 13'.
- the pump 83 delivers the bitumen through a drain cook 85 and a line 86 to a control valve 87 whereby this bitumen can be dispensed in regulated quantities into the trough 69 through a pipe 83.
- a return pipe 89' enables excess bitumen to be returned to the kettle.
- Belt feeder Solid material to be dried can be shovelled by hand into the lower part of the feed ring 28, or optionally a belt conveyor may be provided, as illustrated in. the drawings, for this purpose; It will beunderstood that such supply of solid aggregate material can be carried out either when the plant is on the move or when it is at rest, in either of these cases.
- the belt feeder comprises a hopper 90 having therein a removable partition plate 91 which has the function of dividing the interior of the hopper into two compartments for receiving solid material of difierent types or size, and represents a refinement which may be used when it is desired to use regulated amounts of difierent solid materials in the Each of these compartments is controlled by a sliding door 91 at the rear side of the casing, operable each by its own control screw 92.
- the conveyor belt proper 93 is arranged in the feeder casing 94 so that its upper run is immediately below the lower end of hopper 98, this belt passing over a forward roller 95 and a rear roller 96 which is positioned so that material carried along by the upper run of the belt is discharged directly into the feed ring (see Figure 3).
- the rear roller 96 of the conveyor is driven stepwise from the feed ring 28 of the drier cylinder through a ratchet wheel 97 on the shaft of the rear roller 96 and a co-operating pawl 98 which is movable through a pivotally-mc-unted linkage 99 carrying at its other end a roller running on an edge cam 181 formed around the periphery of the feed ring 28.
- the plant is equipped with a davit 102 for carrying a tar barrel.
- a drier for fluent solid material comprising a drum of hollow elongated form mounted, in use, on a support for rotation about an axis inclined to the horizontal, annular feed means secured around said drum at its higher end and rotatable therewith to feed solid material into the drum interior, said feed means extending over a portion of said drum and having a plurality of chutes therein, apertures in said portion of the drum connecting the chutes with the interior of the drum, annular delivery means secured around the lower end of the drum and rotatable therewith to deliver dried solid material, a discharge device carried by said support and projecting into said delivery means to receive material from said delivery means and burner means carried by said support adjacent said delivery means for injecting hot drying gas through said drum from its lower end in counterfiow to descending solid material.
- A- drier for fluent solid material comprising a drum of hollow elongated form mounted, in use, on a support for rotation about an axis inclined to the horizontal, a feed ring of channel form secured collar-fashion around said drum at its higher end and rotatable therewith, said feed ring having a plurality of chutes therein to feed material through apertures in the drum into the drum interior, an annular delivery ring of channel form secured to the lower end of the drum to receive dried material directly from the drum and to carry it around until cascaded from the ring under gravity, and a measured discharge device carried by said support and projecting into said delivery ring to receive material cascaded therefrom.
- a drier for fluent solid material comprising a drum of hollow elongated form mounted, in use, on a support for rotation about an axis inclined tothe horizontal, a feed ring of channel form secured collar-fashion around said drum at its higher end and rotatable therewith to feed solid material into the drum interior, said feed ring being.
- annular delivery ring of channel form secured to the lower end of the drum to receive dried material directly from the drum and to carry it around until cascaded from the ring under gravity,- a measured discharge device carried by said support and projecting into said delivery ring to receive material cascaded therefrom and burner means carried by said support adjacentsaid delivery means for injecting hot drying gas through said drum from its lower end in counterfiow to descending solid material.
- a vehicle for preparing a mixture of solid ballast and a binder of bituminous material comprising a wheeled chassis, a drum mounted on said chassis at an inclination to the horizontal, means for rotating saiddrum about its axis, annular feed means secured around said drum at its higher end and rotatable therewith, said feed means including a plurality of chutes therein to feed solid material through apertures in the drum into the drum interior, annular delivery means secured around the lower end of the drum and rotatable therewith to deliver dried solid material, a discharge device carried by said chassis and projecting into said delivery means to receive material from said delivery means, burner means carried by said chassis adjacent the delivery means for injecting hot drying gas through said drum from its lower end in counterflow to descending solid material, a mixer on said chassis for receiving dried solid ballast from said discharge device and equipment mounted on said vehicle for melting the bituminous material and passing it to the mixer.
- a vehicle for preparing a mixture of solid ballast and a binder of bituminous material comprising a wheeled chassis, a drum mounted on said chassis at an inclination to the horizontal, means for rotating said drum about its axis, a feed ring of channel form secured collan fashion around said drum at its higher end and rotatable therewith to feed solid material into the drum interior, said feed ring being divided up internally to form radial pockets and radial guide channels each communicating with an aperture in the wall of the drum, an annular delivery ring of channel form having scoopforming members spaced around the interior of its peripheral wall, said delivery ring forming an enlarged extension of the lower end of the drum and communicating directly with the interior of the latter, a measured discharge device carried by said chassis and projecting into said delivery ring to receive material cascaded therefrom, burner means carried by said chassis adjacent the said delivery means for injecting hot drying gas through said drum from its lower end in counterflow to descend ing solid material, a mixer on said chassis for receiving dried solid ballast from said discharge device and
- chute upper end closure device comprises a sliding cover and the lower end closure device a pivoted door, said cover and door being interlinked for movement in unison.
- a vehicle according to claim 8 further including a supply hopper mounted above the upper run of said conveyor and having at least one adjustable door controlling the exit of solid ballast from said hopper on said conveyor.
- a vehicle according to claim 9 including at least one partition subdividing said hopper into compartments, a ballast-flow regulating door being furnished for each such compartment.
- a drier according to claim 1 in which the discharge device comprises an inclined batching chute mounted on said support with its upper end projecting into said delivery means from the exterior, a device for closing 13.
- a drier according to claim 2 further including an endless conveyor for the solid material to be dried, pivotally mounted on said support with its upper run discharging above the lower part of said feed ring.
- a drier according to claim 13 further including a supply hopper mounted above the upper run of said conveyor and having at least one adjustable door controlling the exit of solid material from said hopper on said conveyor.
- a drier according to claim 14 including at least one partition subdividing said hopper into compartments, a solid-material flow regulating door being furnished for each compartment.
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Description
Nov. 27, 1956 2,772,083
DRIER AND MIXER FOR FLUENT SOLID 'IIIATERIAL Filed March 10, 1954 F. W. PARKER 5 Sheets-Sheet 1 Q. T m mm R E .U l
u 5 mm m Oh Em N mu Nov. 27, 1956 F. w. PARKER 2,772,083
DRIER AND MIXER FOR FLUENT SOLID MATERIAL Filed March 10, 1954 5 Sheets-Sheet 2 Nov. 27, 1956 F. w. PARKER 2,772,033
DRIER AND MIXER FOR FLUENT SOLID MATERIAL.
5 Sheets-Sheet 5 Filed March 10, 1954 mm v 5 om .0 Rm om vm mm mm d wm w? l 8 mm mm Nov. 27, 1956 F. w. PARKER 2,772,033
DRIER AND MIXER FOR FLUENT SOLID MATERIAL Filed March 10, 1954 5 Shqets-Sheet 4 Fig .4.
Nov. 27, 1956 F. w. PARKER DRIER AND MIXER FOR FLUENT SOLID MATERIAL Filed March 10, 1954 5 Sheets-Sheet 5 oaeaeo United States Patent DRIER AND R FORFLUENT SOLID NKATEREAL Frederick William Parker, Leicester, England, assignor to Frederick Parker Limited, Leicester, England, a British company Application March 10, 1954, Serial No. 415,330-
Claims priority, application Great Britain March 10, 1953 15 Claims. (Cl. 263-33) The present invention relates to a: drier for fluent solid materials such as sand, gravel or broken stone, and to mixing plants including such driers.
One object of the invention is to provide an improvedand efiicient drier of this character. Further objects are an improved feed means and improved discharge means for such a drier, and: a mobile drying and mixing plant of compact form including a drier for the purpose indicated.
Hence, the drier of thisinvention comprises a drum of hollow elongated form which, in use, is mounted in inclined fashion for rotation about its axis thereby to forward the solid material through the interior of the drum, from the higher to the lower end, and through hot drying gas projected into the drum from the lower end, said drum having, at the higher end, an annular feed means rotatable therewith for introducing the solid material into the drum interior and, at the lower end, annular delivery means also rotatable with the drum for delivering the dried solid material to' a discharge device.
In the improved drier, which is preferably a cylinder, the drying heat i derived from one or more burners arranged to project a flame and hot combustion gases into the cylinder, e. g. counter to, or in the direction of, the material flow.
The feed means advantageously comprise a ring or wheel secured in collar fashion around the drier cylinder ring, this feedwheel having its rim formed to furnish a duct for solid material to be fed into the cylinder and having radial, or substantially radial blades for conducting the solid material under gravity from the duct to a corresponding admission opening into the cylinder. The use of a rotational series of such blades serves to divide the wheel up into a plurality of pockets which, in turn, supply the solid material to the cylinder as the former rotates, thereby giving a distributed feed.
The delivery means, forming a further part of this invention, are based on a similar principle-to the feedmeans, in that they comprise a ring or drumof larger diameter than the drier cylinder and rotate therewith, and in that they include scoops or blades'which serve toreceive and carry round the fluent material until it is transferred, under gravity, to the required point.
In the case of the delivery means, the supply of solid material is received from the cylinder itself, and the solid material is eventually delivered away from the cylinder. In addition the delivery ring is arranged to form a means for storing, for later discharge, material supplied thereto from the cylinder in excess of immediate delivery requirements.
Thedelivery and storage ring is advantageously adjoined and secured directly to the open lower end of the cylinder and has projecting thereinto, from the rear, the heating burner(s) and a batching or measuring device which can be. controlled so as to discharge measured quantities of the dried stone or the like to the point of use;
The drier and. its feed and. delivery means referred to coupl'ed from this vehicle.
ice
above are advantageously combined in a mobile plant for preparing bituminous mixtures, for example tar mixtures or asphalts, such as are used in road making, as road dressings, and so on, this plant also including equipment for melting the tar or like binder, a mixer proper for admixing the bitumen With the ballast solid material, and a common power ource for driving the various operating parts concerned, such as the rotating drier and the mixer. Hence, the plant can be mounted on a wheeled chassis having an engine which drives the cylinder and the paddles of the mixer.
Furthermore, such a mobile plant can include a con.- veyor, driven for example from the. cylindenfor forwarding the moist, solid ballast ingredients of the mixture. to the drier via the feed means recited above. I
The invention is illustrated in the accompanying drawings in reference to a machine embodying the features thereof. This machine is dedicated to the production of asphalt mixture to be applied to a ground surface, for example for the filling of potholes in a road, airfield, or like surface, and in effect constitutes a mixing plant which can be towed over this surface and. the asphalt mixture prepared in the plant (for example, during its travel) can be deposited ready on. the ground or even, say, into a pothole. In these drawings:
Figure l is a general side view of the plant.
Figure 2 is a plan view of the same as seen in the direction of the arrows lI.ll in Figure l. I
Figure 3 is a longitudinal cross section through the same on the line III-HI of FigureZ.
Figure 4 is a front view of the plant seen in the direction of the arrow IV in Figure l and with parts broken away and in section.
Figure 5 is a view from the opposite end in the direction of the arrows VV of. Figure 1, again with parts broken away and in section.
The plant illustrated is mobile and in the form of av trailer vehiclewith a chassis 1 having longitudinal. sills, as at 2, cross bearers such as 3, road wheels '7, and a towing gear 4' terminating forwardly in a shackle. 5 and towbar attachment 6, whereby it can be coupled to the towing vehicle. The side arms of the towing gear 4 are pivoted to the sills 2' so that they can be raised for coupling to the towing vehicle or lowered on to the ground when the plant is to be used for longer periods in one place and un- In the latter event, supporting jacks are lowered at the forward and rear part of the plant, as indicated by the dotted chain lines 8, to maintain the chassis horizontal when the plant is so arrested. In the drawings the towing gear 4 is shown in-the position it occupies when coupled to a towing vehicle.
The major components of the plant will now be referred to in more detail below.
Power unit This is generally denoted 9 in the drawings and comprises an encased internal combustion engine which is mounted on the right hand side of the plant. This unit serves to operate all the various moving parts of the plant, having for this purpose an output shaft 11 controlled by a clutch with a lever 10.
The shaft 11, through a chain drive 12, operatesa first countershaft 13 for driving a supply pump in a bitumen kettle (see later) and also serving to drive, through a further chain transmission 14-, a second countershaft 15 which, inter alia, operates a fuel pump, the mixer, and the drying cylinder itself (all as will be later described). In addition, the output shaft is connected through a belt and pulley drive- 16 to a blower 17, with an air filter 18, for supplying combustion air to a drying burner.
Drier cylinder and ballast feed and delivery means The drier proper consists of a cylindrical drum 19 which is furnished with a pair of annular collars 20 running on rotary bearings 21 carried on cross bearers of the vehicle chassis and, it will be noted, has its axis slightlyk inclined to the horizontal in the condition of use, i.'e. that illustrated in the drawings. The cylinder 19 is rotatable from a sprocket 22 carried by a stub shaft 23, driven from the countershaft 15'through a universal coupling 24, through a chain drive transmission 25, the chain passing around sprocket 22 and sprocket teeth 26 provided on the periphery of the cylinder 19. I
Internally, the main body of the cylinder is provided with a number of lifter plates 27 which are arranged to pick up the fluent solid ballast material, e. g. sand orgravel, to be dried by passage through the drum and subsequently mixed with the bitumen. and cascade it through the centre of the drum as the latter rotates and as the material gradually progresses from the higher to the lower end of this cylinder in counter flow to hot drying gases.
At itsforward end the cylinder 19 has rigidly secured thereto a feed ring in the form of an external bucket wheel 28 which is open at its frusto-conical end 29 and serves to transfer solid aggregate, fed to the lower part thereof, to the interior of the cylinder 19. for drying passage 'therethrough. Hence this feed ring 28, see particularly Figure 4, is divided into a number of pockets by radial partitions 30 which are connected between the circumferential wall of the feed ring 28 and the wall of the cylinder 19 at this part. In addition a shorter but radial deflector plate 31 is connected to the cylinder 19 opposite each partition 30, this deflector plate 31 having an angled portion 32 whereby it is connected to the periphery 'of'the ring 28 and serving as a guide for introducing solid material into the feed channel between the two opposed walls 30 and 31 concerned. This channel leads to a rectangular opening 33 in the corresponding part of the cylinder wall, whereby as the cylinder 19 and its feed ring rotate, solid material received at the lower part of this ring is carried upwardly in the corresponding pocket in this ring, a part thereof passing into the channel 30, 31 for delivery to the interior of the cylinder 19 as this channel nears its upper position. Inthis way the amount of solid material fed into the drum is controlled.
Onentering the drum, the solid material is picked up by shaped deflector plates 34, disoosed around the higher end of this cylinder so as to initiate its forward movement through the drum by conducting it at an early stage to the centre of the latter.
Rigidly'connected to the cylinder 19 at its lower end is an outwardly extending annular delivery and storage 3 ring 35 by means of which the dried solid material is discharged to the mixer (see later); This delivery and storage ring 35' is furnished internally around its peripheral wall with a series of angled elevating scoops 36 such that, as the ring rotates, dried material flowing in from the cylinder 19 is carried, around by the approoriate scoop 36 and eventually thrown down as the latter reaches an appropriate. elevated position. As a result it either enters a batching chute, located at this end of the machine, for delivery to the mixer, or drops through to the lower part of the ring 35 and is carried around again, whereby the latter serves for the temporary storage of excess solid aggregate'material. ring 37 provides a running seal for theopen rear end of the delivery and storage ring 35. I
Drying equipment Mounted .in the plant so as to direct hot gases forwardly through the cylinder 19 from the rear end of the storage ring 35, is a burner 38 having a hood 39 to protect it from solid aggregate dropping through the A sealing ring 35 as mentioned above. This burner is provided with a torch rod 40 and is supplied with fuel under pressure, injected by the blower 17 from a fuel tank 41 through a supply line 42, incorporating a control tap 43 and having a bypass return 44 to the fuel tank, and with air from blower 17 through an air line 45 incorporating a pressure gauge 46 and a control valve 47.
The hot gases from the burner 38 pass through the rearwardly flowing and cascaded solid material as it passes downwards through the cylinder 19, and these gases are eventually discharged through a chimney the lower part 48 of which surrounds the open forward end of the cylinder 19. This chimney 48 is provided with a hinged upper section 49 which can be lowered, as indicated in chain dotted lines in Figure 1, when the plant is travelling along a road.
Batching chute This device, generally denoted 50 in the drawings, is provided at the rear side of the delivery and storage ring'35 and projects into the latter so as'to receive dried solid material therefrom and to conduct it in regulated quantity into the mixer of the plant. This batching chute comprises an inclined chute channel 51, the upper and lower ends of which are controlled respectively by a sliding cover 52 and a'pivoted door '53. This plate 52 and door 53 are operable from a common linkage in such a way that opening of one is accompanied by closure of the other and vice versa, thus precluding the discharge at any time of greater quantity of solid material than the capacity of this batching chute. Hence, the cover 52, which has its front part formed as a triangular deflector and its rear part as a flat plate,
' is movable by a pair of arms 54 articulated to the plate" portion and connected to levers 55 which are pivoted at their lower ends 56 and are rockable in common by means of a handle 57. Articulated to the levers 55 through links 58 are a pair of sector plates 59 between which the door 53 is carried.
Hence, operation of the handle 57 in one direction will rock the levers 55 so as to draw the cover 52 inwards, the rear plate-form section of this cover running on a track formed by bars 60, so that the deflector section closes the upper end of the chute 50, and at the same time the door 53 will be rocked by this lever so as to slide over the curved lower end of the chute and open the latter to allow the solid material in the chute to discharge directly into the mixer.
Mixer This mixer is mounted at the rear of the plant and serves for the mixing together of the dried aggregate material, batched thereinto as described above, and bituminous material in liquid condition to be supplied thereto from a bitumen kettle described hereunder. In the latter event the mixer may be provided with heating means, as in the specific example under description, but this is an optional feature.
The mixer comprises an opemtopped container 61 containing a pair of parallel shafts 62 and 63 each equipped with radial paddle blades 64 carrying heater tips 65 at their outer ends. The shaft 62 is operated through a chain drive 66 from the countershaft 15 and transmits the drive at its rear end through toothed gear wheels 67 to the other shaft 63. The solid aggregate material is poured from the batching device 50 into the upper end of the mixer chamber which is provided with a protective grid 68. Mounted above the right hand side of the casing 61 is a bitumen trough or bucket 69 which receives heated bitumen from the bitumen kettle (see below) and can be tipped by a handle 70 at appropriate times to pour into the mixer. This trough 69 is advantageously equipped with a bitumen-level gauge (not shown) to guide the user. 4
in addition, the casing of this mixer is provided at its lower later l Parts with hollow jackets 71 which receive am ss hot air through ducting 72 and '73 from the bitumen heating kettle, thereby to keep the bitumen and the mixture warm. whilst the mixing operation is in progress.
In addition, the paddle mixer is furnished at its lower part with a door 74 which is operable through a linkage 75 by a handle 76 for the discharge from its bottom at prescribed times of a quantity of the asphalt or bituminous mixture.
Bitumen kettle and supply connections The bitumen kettle comprises a tank 79 which is supplied with bitumen from a barrel warming chamber Sillocated at the underside of the vehicle through a mesh screen (not shown). This bitumen includes a heater assembly, generally designated 81', supplied from a fuel tank 82 and serving to liquify this bitumen for delivery to the bitumen trough and paddle mixer.
Hence, the kettle comprises a pump 83 which is driven through a belt 34 from the countershaft 13'. The pump 83 delivers the bitumen through a drain cook 85 and a line 86 to a control valve 87 whereby this bitumen can be dispensed in regulated quantities into the trough 69 through a pipe 83. A return pipe 89' enables excess bitumen to be returned to the kettle.
Belt feeder Solid material to be dried can be shovelled by hand into the lower part of the feed ring 28, or optionally a belt conveyor may be provided, as illustrated in. the drawings, for this purpose; It will beunderstood that such supply of solid aggregate material can be carried out either when the plant is on the move or when it is at rest, in either of these cases.
The belt feeder comprises a hopper 90 having therein a removable partition plate 91 which has the function of dividing the interior of the hopper into two compartments for receiving solid material of difierent types or size, and represents a refinement which may be used when it is desired to use regulated amounts of difierent solid materials in the Each of these compartments is controlled by a sliding door 91 at the rear side of the casing, operable each by its own control screw 92.
The conveyor belt proper 93 is arranged in the feeder casing 94 so that its upper run is immediately below the lower end of hopper 98, this belt passing over a forward roller 95 and a rear roller 96 which is positioned so that material carried along by the upper run of the belt is discharged directly into the feed ring (see Figure 3). The rear roller 96 of the conveyor is driven stepwise from the feed ring 28 of the drier cylinder through a ratchet wheel 97 on the shaft of the rear roller 96 and a co-operating pawl 98 which is movable through a pivotally-mc-unted linkage 99 carrying at its other end a roller running on an edge cam 181 formed around the periphery of the feed ring 28.
Finally, the plant is equipped with a davit 102 for carrying a tar barrel.
Wnat I claim then is:
l. A drier for fluent solid material, comprising a drum of hollow elongated form mounted, in use, on a support for rotation about an axis inclined to the horizontal, annular feed means secured around said drum at its higher end and rotatable therewith to feed solid material into the drum interior, said feed means extending over a portion of said drum and having a plurality of chutes therein, apertures in said portion of the drum connecting the chutes with the interior of the drum, annular delivery means secured around the lower end of the drum and rotatable therewith to deliver dried solid material, a discharge device carried by said support and projecting into said delivery means to receive material from said delivery means and burner means carried by said support adjacent said delivery means for injecting hot drying gas through said drum from its lower end in counterfiow to descending solid material.
2. A- drier for fluent solid material comprising a drum of hollow elongated form mounted, in use, on a support for rotation about an axis inclined to the horizontal, a feed ring of channel form secured collar-fashion around said drum at its higher end and rotatable therewith, said feed ring having a plurality of chutes therein to feed material through apertures in the drum into the drum interior, an annular delivery ring of channel form secured to the lower end of the drum to receive dried material directly from the drum and to carry it around until cascaded from the ring under gravity, and a measured discharge device carried by said support and projecting into said delivery ring to receive material cascaded therefrom.
3. A drier for fluent solid material, comprising a drum of hollow elongated form mounted, in use, on a support for rotation about an axis inclined tothe horizontal, a feed ring of channel form secured collar-fashion around said drum at its higher end and rotatable therewith to feed solid material into the drum interior, said feed ring being. divided up internally to form radial pockets and radial guide channels each communicating with an aperture in the wall of the drum, an annular delivery ring of channel form secured to the lower end of the drum to receive dried material directly from the drum and to carry it around until cascaded from the ring under gravity,- a measured discharge device carried by said support and projecting into said delivery ring to receive material cascaded therefrom and burner means carried by said support adjacentsaid delivery means for injecting hot drying gas through said drum from its lower end in counterfiow to descending solid material.
4. A vehicle for preparing a mixture of solid ballast and a binder of bituminous material, comprising a wheeled chassis, a drum mounted on said chassis at an inclination to the horizontal, means for rotating saiddrum about its axis, annular feed means secured around said drum at its higher end and rotatable therewith, said feed means including a plurality of chutes therein to feed solid material through apertures in the drum into the drum interior, annular delivery means secured around the lower end of the drum and rotatable therewith to deliver dried solid material, a discharge device carried by said chassis and projecting into said delivery means to receive material from said delivery means, burner means carried by said chassis adjacent the delivery means for injecting hot drying gas through said drum from its lower end in counterflow to descending solid material, a mixer on said chassis for receiving dried solid ballast from said discharge device and equipment mounted on said vehicle for melting the bituminous material and passing it to the mixer.
5. A vehicle for preparing a mixture of solid ballast and a binder of bituminous material, comprising a wheeled chassis, a drum mounted on said chassis at an inclination to the horizontal, means for rotating said drum about its axis, a feed ring of channel form secured collan fashion around said drum at its higher end and rotatable therewith to feed solid material into the drum interior, said feed ring being divided up internally to form radial pockets and radial guide channels each communicating with an aperture in the wall of the drum, an annular delivery ring of channel form having scoopforming members spaced around the interior of its peripheral wall, said delivery ring forming an enlarged extension of the lower end of the drum and communicating directly with the interior of the latter, a measured discharge device carried by said chassis and projecting into said delivery ring to receive material cascaded therefrom, burner means carried by said chassis adjacent the said delivery means for injecting hot drying gas through said drum from its lower end in counterflow to descend ing solid material, a mixer on said chassis for receiving dried solid ballast from said discharge device and equipment mounted on said vehicle for melting the bituminous material and passing it to the mixer.
-6. A vehicle according to claim 4, in which the discharge device comprises an inclined batching chute having its upper end projecting into the drum from the exterior and its lower end located above the mixer, a device for closing each of the upper and lower ends of the chute, and means operable to simultaneously move the closure device for the upper end of said chute into closure position and the closure device for the lower end of the chute into open position, and .vice versa.
7. A vehicle according to claim 6, in which the chute upper end closure device comprises a sliding cover and the lower end closure device a pivoted door, said cover and door being interlinked for movement in unison.
8. A vehicle according to claim 5, further including an endless conveyor for solid ballast pivotally mounted on said chassis with its upper run discharging above the lower part of said feed ring.
9. A vehicle according to claim 8, further including a supply hopper mounted above the upper run of said conveyor and having at least one adjustable door controlling the exit of solid ballast from said hopper on said conveyor.
10. A vehicle according to claim 9, including at least one partition subdividing said hopper into compartments, a ballast-flow regulating door being furnished for each such compartment.
11. A drier according to claim 1, in which the discharge device comprises an inclined batching chute mounted on said support with its upper end projecting into said delivery means from the exterior, a device for closing 13. A drier according to claim 2 further including an endless conveyor for the solid material to be dried, pivotally mounted on said support with its upper run discharging above the lower part of said feed ring.
14. A drier according to claim 13, further including a supply hopper mounted above the upper run of said conveyor and having at least one adjustable door controlling the exit of solid material from said hopper on said conveyor.
15. A drier according to claim 14, including at least one partition subdividing said hopper into compartments, a solid-material flow regulating door being furnished for each compartment.
References Cited in the file of this patent UNITED STATES PATENTS 416,950 Ransome Dec. 10, 1889 1,105,812 McKaig Aug. 4, 1914 1,363,230 Clark Dec. 28, 1920 1,836,754 Hepburn Dec. 15, 1931 2,344,228 Barber Mar. 14, 1944 2,421,345 McConnaughay May 27, 1947 2,487,887 McEachron Mar. 15, 1949
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2772083X | 1953-03-10 |
Publications (1)
Publication Number | Publication Date |
---|---|
US2772083A true US2772083A (en) | 1956-11-27 |
Family
ID=10915045
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US415330A Expired - Lifetime US2772083A (en) | 1953-03-10 | 1954-03-10 | Drier and mixer for fluent solid material |
Country Status (2)
Country | Link |
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US (1) | US2772083A (en) |
DE (1) | DE1146090B (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3625489A (en) * | 1970-08-07 | 1971-12-07 | Infra Radiant Corp | Road repair machine |
US3857552A (en) * | 1972-03-28 | 1974-12-31 | K Ohlson | Asphalt mixing plants for making asphalt concrete mix |
US3990684A (en) * | 1974-03-28 | 1976-11-09 | Abie Seskin | Materials mixing apparatus |
US20110129296A1 (en) * | 2006-05-22 | 2011-06-02 | Wesley Van Velsor | Aggregate pre-heating systemsand method |
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US416950A (en) * | 1889-12-10 | Concrete-mixing machine | ||
US1105812A (en) * | 1914-08-04 | Apfiioaflo-h | ||
US1363230A (en) * | 1916-05-16 | 1920-12-28 | Clark John Earnest | Process and apparatus of treating material |
US1836754A (en) * | 1929-08-10 | 1931-12-15 | Hepburn Donald Mcknight | Apparatus for preparing paving compositions |
US2344228A (en) * | 1941-07-25 | 1944-03-14 | Barber Greene Co | Mixing plant |
US2421345A (en) * | 1944-11-04 | 1947-05-27 | Kenneth E Mcconnaughay | Mixer |
US2487887A (en) * | 1945-12-22 | 1949-11-15 | Paul R Mceachran | Vehicular mixing plant |
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DE279985C (en) * | ||||
DE421456C (en) * | 1923-10-27 | 1925-11-12 | Ammann A G U | Drying drum for machines for processing road construction material |
US1836261A (en) * | 1928-04-30 | 1931-12-15 | Madsen Iron Works | Portable asphalt mixing plant |
DE613341C (en) * | 1930-05-22 | 1935-05-17 | Alfelder Eisenwerk Otto Wessel | Device for making road construction macadam |
US2397581A (en) * | 1944-08-23 | 1946-04-02 | Dallas Machine & Locomotive Wo | Apparatus for preparing paving materials |
DE812413C (en) * | 1950-01-26 | 1951-08-30 | Kinetic Mixer Company | Method and device for mixing compounds, in particular road building materials |
-
1954
- 1954-03-06 DE DEP11476A patent/DE1146090B/en active Pending
- 1954-03-10 US US415330A patent/US2772083A/en not_active Expired - Lifetime
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
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US416950A (en) * | 1889-12-10 | Concrete-mixing machine | ||
US1105812A (en) * | 1914-08-04 | Apfiioaflo-h | ||
US1363230A (en) * | 1916-05-16 | 1920-12-28 | Clark John Earnest | Process and apparatus of treating material |
US1836754A (en) * | 1929-08-10 | 1931-12-15 | Hepburn Donald Mcknight | Apparatus for preparing paving compositions |
US2344228A (en) * | 1941-07-25 | 1944-03-14 | Barber Greene Co | Mixing plant |
US2421345A (en) * | 1944-11-04 | 1947-05-27 | Kenneth E Mcconnaughay | Mixer |
US2487887A (en) * | 1945-12-22 | 1949-11-15 | Paul R Mceachran | Vehicular mixing plant |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3625489A (en) * | 1970-08-07 | 1971-12-07 | Infra Radiant Corp | Road repair machine |
US3857552A (en) * | 1972-03-28 | 1974-12-31 | K Ohlson | Asphalt mixing plants for making asphalt concrete mix |
US3990684A (en) * | 1974-03-28 | 1976-11-09 | Abie Seskin | Materials mixing apparatus |
US20110129296A1 (en) * | 2006-05-22 | 2011-06-02 | Wesley Van Velsor | Aggregate pre-heating systemsand method |
Also Published As
Publication number | Publication date |
---|---|
DE1146090B (en) | 1963-03-28 |
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