US20150376847A1

US20150376847A1 - Additive mixing and delivery system for rotary mixers

Info

Publication number: US20150376847A1
Application number: US14/846,691
Authority: US
Inventors: Brian J. Schlenker
Original assignee: Caterpillar Paving Products Inc
Current assignee: Caterpillar Paving Products Inc
Priority date: 2015-09-04
Filing date: 2015-09-04
Publication date: 2015-12-31

Abstract

An additive mixing and delivery system for a rotary mixer is provided. The additive mixing and delivery system includes an onboard slurry tank, an additive pump, a water pump, a spray unit, and a rotor. The onboard slurry tank receives additive and water. The onboard slurry tank mixes the additive with water to form a slurry. The additive pump delivers the additive to the onboard slurry tank. The water pump delivers the water to the onboard slurry tank. The spray unit delivers the slurry from the onboard slurry tank to a work surface. The rotor includes a number of cutting tools to disintegrate the work surface to form a disintegrated work surface. Further, the slurry is mixed with the disintegrated work surface to form an additive laden work surface.

Description

TECHNICAL FIELD

The present disclosure generally relates to machines used for road reclamation and soil stabilization purposes. More particularly, the present disclosure relates to an additive mixing and delivery system for rotary mixers.

BACKGROUND

A rotary mixer is generally used as a soil stabilizer to cut, mix, and pulverize native in-place soils with additives or aggregates. This is done to modify and stabilize the soil for a strong base. The rotary mixer may also be used as a road reclaimer to pulverize a work surface, such as asphalt. The pulverized layer may be mixed with an underlying base to create a new road surface for stabilization of deteriorated roadways. Optionally, the rotary mixer may add asphalt emulsions or other binding agents to create the new road surface during pulverization. The rotary mixer may also be used to remove a layer from the ground. The rotary mixers generally use a rotor equipped with cutting tools to cut into the ground.
Typically a water truck, an additive truck, and a slurry truck are required to provide slurry to the rotary mixer. The slurry truck receives the water and the additive, respectively, from the water truck and the additive truck. The slurry is mixed in the slurry truck and transported in the slurry truck or pumped directly to the rotary mixer. This process is time-consuming as it requires a concerted efforts from multiple machines and work personnel. Moreover, additional equipment, such as a slurry tank, multiple hoses, pumps, metering units are separately required, to deliver the slurry to the rotary mixer for soil reclamation.
German Patent Publication Number DE202004004954 relates to a storage vessel for the additive to be mixed with the soil. The storage vessel is supported on top of the vehicle. A dosing unit is used to add the additive to the soil and a rotary mixing device mixes the additive with the soil. However, the storage vessel of the '954 reference does not provide a solution to bind the mixture of the additive with the soil, during a delivery process. This results in creation of large dust clouds in situ when the mixture is spread onto the ground.
The present disclosure seeks to address one or more of the problems associated with known.

SUMMARY OF THE INVENTION

Various aspects of the disclosure relate to an additive mixing and delivery system for a rotary mixer. The rotary mixer is adapted to convert a work surface to an additive laden work surface. The additive mixing and delivery system includes an onboard slurry tank, an additive truck, a water truck, a spray unit, and a rotor. The onboard slurry tank includes an additive inlet to receive an additive and a water inlet to receive water. The onboard slurry tank is configured to mix the additive with water to form a slurry. The additive truck delivers the additive to the onboard slurry tank. The water truck delivers the water to the onboard slurry tank. The spray unit is connected to the onboard slurry tank and delivers the slurry from the onboard slurry tank to the work surface. The rotor is configured to disintegrate the work surface to form a disintegrated work surface and further mix the slurry with the disintegrated work surface to form the additive laden work surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an exemplary machine having an additive mixing and delivery system, in accordance with the concepts of the present disclosure;

FIG. 2 is schematic view of the additive mixing and delivery system of FIG. 1, in accordance with the concepts of the present disclosure; and

FIG. 3 is a diagrammatic view of a portion of a mixing chamber of FIG. 1, in accordance with the concepts of the present disclosure.

DETAILED DESCRIPTION

Referring to FIG. 1, there is shown an exemplary machine 10, in this case, a rotary mixer 10. Although FIG. 1 shows the rotary mixer 10, other machines used in milling, road reclamation, soil stabilization, surface pulverization, or other applications may also be contemplated. The rotary mixer 10 is adapted to convert a work surface 12 (shown in FIG. 3) to an additive laden work surface 14 (shown in FIG. 3). According to FIG. 1, the rotary mixer 10 includes a frame 16, a cab 18, a mixing chamber 20, front wheels 22, rear wheels 24, an engine compartment 26, and an additive mixing and delivery system 28.
The frame 16 includes a front portion 30 and a rear portion 32. The front portion 30 and the rear portion 32 are supported on the front wheels 22 and the rear wheels 24, respectively. The front wheels 22 and the rear wheels 24 are pivotally connected to the frame 16, via respective axles (not shown). Further, the front portion 30 supports the engine compartment 26 and the cab 18. The frame 16 also supports the mixing chamber 20 proximate to a center portion of the rotary mixer 10 and between the wheels 22 and 24.
The engine compartment 26 houses a power source (not shown). The power source may be configured to electrically, mechanically, hydraulically, and/or pneumatically power the wheels 22 and 24.
Referring to FIGS. 1 and 2, the additive mixing and delivery system 28 is positioned on the rear portion 32. The additive mixing and delivery system 28 facilitates mixing of additive with a binding agent, to form a slurry 34 (shown in FIG. 3). The additive may be cement, lime, lime-cement-fly ash (LCF), or combinations of these materials. The additive mixing and delivery system 28 receives the additive and the water from an additive truck 36 and a water truck 38, respectively, via a first hose 40 and a second hose 42. The additive mixing and delivery system 28 includes an additive pump 44, an additive delivery hose 46, a first metering unit 48, a water pump 50, a water delivery hose 52, a second metering unit 54, an onboard slurry tank 56, a slurry pump 58, a slurry metering unit 60, a slurry delivery hose 62, a spray unit 64, and a controller 66.
The additive pump 44 is disposed on the rotary mixer 10. The additive pump 44 is connected to the additive truck 36 via the first hose 40, for receipt of the additive. The additive pump 44 delivers the additive to the first metering unit 48.
The first metering unit 48 is in fluid communication with the additive delivery hose 46. The first metering unit 48 may provide provisions for additive metering and filtration. The first metering unit 48 measures a precise amount of additive fed through the additive delivery hose 46. The first metering unit 48 works in conjunction with the controller 66 to alter a flow of the additive based on operator feed. Hence, the first metering unit 48 allows an operator to set a first pre-determined discharge amount of the additive to be delivered from the additive pump 44.
The water pump 50 is disposed on the rotary mixer 10. The water pump 50 is fluidly connected to the water truck 38 via the second hose 42, for receipt of water. The water pump 50 delivers water to the second metering unit 54.
The second metering unit 54 is in fluid communication with the water delivery hose 52. The second metering unit 54 may provide provisions for water metering and filtration. The second metering unit 54 measures a precise amount of water fed through the water delivery hose 52. The second metering unit 54 operates in conjunction with the controller 66 to alter a flow of the water based on operator input. Hence, the second metering unit 54 allows an operator to set a second pre-determined discharge amount of the water to be delivered from the water pump 50.
The onboard slurry tank 56 is coupled to the rear portion 32 of the rotary mixer 10. The onboard slurry tank 56 is connected to the first metering unit 48 and the second metering unit 54. The onboard slurry tank 56 includes an additive inlet 68, a water inlet 70, a tank chamber 72, and an outlet 74. The additive inlet 68 and the water inlet 70 facilitate delivery of the additive and the water, respectively, to the tank chamber 72. The additive and the water are mixed in the tank chamber 72, which results in formation of the slurry 34. The slurry 34 is discharged from the onboard slurry tank 56, via the outlet 74. The outlet 74 is in fluid communication with the slurry delivery hose 62. The slurry delivery hose 62 allows flow of the slurry 34 to the slurry pump 58.
The slurry pump 58 is fluidly connected to the onboard slurry tank 56. The slurry pump 58 is in fluid communication with the slurry metering unit 60. The slurry metering unit 60 measures a pre-determined amount of the slurry 34 fed to the spray unit 64, which is in fluid communication with the slurry metering unit 60.
Referring to FIG. 3, the mixing chamber 20 is shown with the spray unit 64, the slurry metering unit 60, and the slurry pump 58 in conjunction with the controller 66. It is shown, that the rotary mixer 10 and the mixing chamber 20 moves along the work surface 12 composed of work surface particles. In this embodiment, the work surface 12 is composed of a base layer 76 and an asphalt layer 78, which is disposed over the base layer 76. As the rotary mixer 10 and mixing chamber 20 move along the work surface 12, the asphalt layer 78 and the base layer 76 breaks apart and pulverizes into pieces, which are then used to form a disintegrated work surface 80. In an embodiment, the work surface 12 is only the base layer 76, which is pulverized by the rotary mixer 10 to form the disintegrated work surface 80. This is done for the purpose for soil stabilisation.
The mixing chamber 20 includes a front door 82, a rear door 84, an adjustable sizing mechanism 86, and a rotor 88. The mixing chamber 20 includes a first end 90 and a second end 92. The front door 82 is positioned at the first end 90. Position of the front door 82 is controlled by the controller 66, and in conjunction with various sensors (not shown) positioned at the front door 82. The front door 82 allows entry of the work surface particles into the mixing chamber 20. Position of the front door 82 affects the degree of pulverization by regulating the amount, direction, and speed of material flow into the mixing chamber 20
The rear door 84 is positioned at the second end 92. Position of the rear door 84 is controlled by the controller 66, and in conjunction with various sensors (not shown) positioned at the rear door 84. The rear door 84 facilities exit of the pulverised pieces to form the additive laden work surface 14. The position of the rear door 84 affects the degree of pulverization by regulating the amount, direction, and speed of material flow through the mixing chamber 20. The additive laden work surface 14 is a mixture of the asphalt and the base material treated with the slurry 34. In an embodiment, the additive laden work surface 14 is a mixture of the base material and the slurry 34.
The slurry 34 may be injected into the mixing chamber 20 by the spray unit 64. The spray unit 64 is fluidly connected to the slurry metering unit 60. The spray unit 64 includes treatment nozzles 94 for injection of the slurry 34. The treatment nozzles 94 are mounted on a top side 96 of the mixing chamber 20. The treatment nozzles 94 are thus adapted to inject the slurry 34 from the onboard slurry tank 56 downwardly into the confines of the mixing chamber 20. The slurry 34 then mixes with the pulverised pieces created by action of the rotor 88.
The rotor 88 is placed inside the mixing chamber 20 between the front door 82 and the rear door 84. The rotor 88 is rotatably mounted within the mixing chamber 20. The rotor 88 is disposed laterally rearward from the spray unit 64 and transversally to a front-to-rear flow path of the material through the mixing chamber 20. The rotor 88 is often configured to move up or down (shown by arrow 98) in the mixing chamber 20, along a known path. In addition, the rotor 88 includes a number of cutting tools 100. The cutting tools 100 are spaced apart along a cylindrical outer surface in a general nonrepeating checkerboard pattern. The cutting tools 100 may be pointed in a direction of rotation (indicated by an arrow 102), such that a tip end of each cutting tool 100 is driven into work surface 12 by a rotation of the rotor 88. The cutting tools 100 drive into the work surface 12 and demolish or break the work surface 12 into pieces.
The adjustable sizing mechanism 86 is used to control a degree of pulverization of the work surface 12. The adjustable sizing mechanism 86, as will be described below, may be positioned at various distances from the rotor 88 to set the degree of pulverization or, in other words, to set the maximum size or diameter of disintegrated work surface particles 104 used in the layer of reclaimed material.

INDUSTRIAL APPLICABILITY

In operation, the water truck 38 and the additive truck 36 supply the water and the additive, respectively, to the rotary mixer 10. The water pump 50 and the additive pump 44 positioned on the rotary mixer 10, receive the water and the additive. The first metering unit 48 and the second metering unit 54, respectively, provides the first pre-determined amount and the second pre-determined amount to the onboard slurry tank 56. The additive mixes with the water to form the slurry 34. The slurry 34 is then routed to the spray unit 64 via the slurry pump 58 and the slurry metering unit 60. The spray unit 64 delivers the slurry 34 to the treatment nozzles 94 which inject the slurry 34 into the mixing chamber 20.
Simultaneously, as the rotary mixer 10 moves in the direction (shown by arrow 106), in the mixing chamber 20, during rotation of the rotor 88 (shown by arrow 102), the cutting tools 100 are forced through work surface 12. This results in breakage of the work surface 12 into the disintegrated work surface 80. The disintegrated work surface 80 then mix with the slurry 34 to form treated soil particles. These treated particles then form the additive laden work surface 14. The disclosed additive mixing and delivery system 28 is beneficial in reducing time used in formation of the additive laden work surface 14 by the rotary mixer 10. This owes to the fact that the mixing of the water and the additive is performed onboard the rotary mixer 10. In addition, the mixing of the slurry 34 with the disintegrated work surface 80 is simultaneously done to form the additive laden work surface 14. Hence, the treatment of the work surface 12 takes less times. It is also convenient for refiling as the slurry 34 tank is onboard. This also eliminates a requirement of a separate slurry 34 tank for mixing of water received from the water truck 38 and the additive received from the additive truck 36. Further, this reduces the number of hoses used in the process to supply the slurry 34 to the work surface 12. Therefore, the disclosed system is convenient, less complex, cost effective, and time saving.
The many features and advantages of the disclosure are apparent from the detailed specification, and thus, are intended by the appended claims to cover all such features and advantages of the disclosure that fall within the true spirit and scope thereof. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the disclosure to the exact construction and operation illustrated and described herein. Accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the disclosure.

Claims

What is claimed is:

1. An additive mixing and delivery system for a rotary mixer, the rotary mixer adapted to convert a work surface to an additive laden work surface, the system comprising:

an onboard slurry tank including an additive inlet to receive an additive and a water inlet to receive water, the onboard slurry tank configured to mix the additive with water to form a slurry;

an additive pump for delivering the additive to the onboard slurry tank;

a water pump for delivering the water to the onboard slurry tank;

a spray unit connected to the onboard slurry tank and configured to deliver the slurry from the onboard slurry tank to the work surface; and

a rotor configured to disintegrate the work surface to form a disintegrated work surface and further mix the slurry with the disintegrated work surface to form the additive laden work surface.