CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to an excavator for continuously digging and moving material. More specifically, the present invention is related to excavators for continuously digging material such as soil, sand, gravel and the like, and moving that excavated material to a desired location, or to transporting vehicles.
2. Description of the Related Art
Machines and devices for excavating soil, sand, gravel, and the like, are known in the art. Many such excavating machines incorporate self-propelled vehicles have digging mechanisms supported on extendable booms, including various hydraulically actuated excavators and backhoes. Such excavators are often large, heavy vehicles, and, while they can be effective excavators, they can do great damage to the surfaces on which they operate. For example, where it is necessary to remove sand from a sand trap on a golf course, large, heavy excavators can do great damage to the area surrounding the trap. Further, such excavators tend to have limited mechanisms for conveying excavated material to a second location, or to a transporting vehicle. In this regard, the excavation operation generally must be halted while the boom of the excavator is moved to convey the excavated material to the desired location, or to a waiting truck. Accordingly, excavation is not continuous, and can be time consuming. Whereas belt and bucket conveyors are sometimes used to convey excavated materials, the conveyors are generally separate devices, and the excavator must still cease the excavation operation while excavated material is loaded onto the conveyor.
Therefore, there is a need for a light weight excavator which can excavate a large area while being positioned in one location so as to limit damage to the area surrounding the excavation. There is also a need for a light weight excavator which can efficiently convey the excavated material to a desired location, or to a transporting vehicle, while the excavation process continues.
Certain prior art excavating and conveying devices are disclosed in U.S. Pat. Nos. 6,808,354; 6,447,238; 6,305,896; 4,897,183; 4,919,583; 3,316,977; 2,363,682; 1,809,796; and 1,554,972.
BRIEF SUMMARY OF THE INVENTION
The present invention provides an excavator for excavating a selected material such as dirt, sand, or gravel, and conveying the excavated material to a desired location, or to transporting vehicles. The excavator includes a mobile support which in one embodiment is a self-propelled motor vehicle, and includes a boom assembly mounted on the mobile support. The boom assembly has at least one extendable section, with the extendable section being selectively extendable and retractable. An excavating assembly is mounted at the distal end of the extendable second of the boom assembly so as to extend and retract with the extendable section. In one embodiment the excavating assembly includes a bucket conveyor which serves to dig, or scoop up, the selected material and convey such material to a conveying assembly which, in turn, conveys the excavated material to a selected location off of the mobile support. In this regard, the conveying assembly includes at least one extendable conveyor that is extendable and retractable with the extendable section of the boom assembly such that the extendable conveyor is in position to receive excavated material from the excavating assembly as the excavating assembly is extended and retracted. Accordingly, the excavation operation and the conveying of the excavated material off of the mobile support can continue simultaneously as the excavating assembly is repositioned to excavate new areas.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The above-mentioned features of the invention will become more clearly understood from the following detailed description of the invention read together with the drawings in which:
FIG. 1 is a side elevation view of an excavator of the present invention;
FIG. 2 is a side elevation view of an excavator of the present invention;
FIG. 3 is a top plan view of an excavator of the present invention;
FIG. 4 is a top plan view of an alternate embodiment of an excavator of the present invention;
FIG. 5 is a side view of the excavating assembly of an excavator of the present invention;
FIG. 6 is a partial perspective view of the excavating assembly of an excavator of the present invention;
FIG. 7 is a schematic illustration of an example of a hydraulic system used by an excavator of the present invention;
FIG. 8A is a partial side elevation view of a further alternate embodiment of an excavator of the present invention; and
FIG. 8B is a partial side elevation view of the further alternate embodiment of an excavator of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
An excavator incorporating various features of the present invention is illustrated generally at 10 in the drawings. The excavator 10 is designed to continuously excavate and convey soil, sand, gravel, or the like. In the drawings the excavator 10 is illustrated as conveying the excavated material to one or more transporting vehicles, but it will be recognized that the excavator 10 could be used to convey the excavated materials to containers, or to simply deposit the excavated material at a new location proximate the excavator 10.
As will be discussed in detail below, the excavator 10 generally includes an excavating assembly 12 that serves as a digging and/or scooping mechanism, and includes a conveying assembly 14 that conveys the material excavated by the excavating assembly from the excavating assembly 12 to a location for accumulation or transport. Further, the excavator 10 includes a mobile support that supports the excavating assembly 12 and the conveying assembly 14, and that allows the excavator 10 to be selectively moved to desired locations. As best illustrated in FIGS. 1 and 2, in one embodiment the mobile support is a self-propelled motor vehicle 16 having a rear section 18 for rotatably supporting various components of the excavator 10. It will, however, be understood that the mobile support need not be self-propelled. For example, the mobile support could be a trailer or the like. Further, whereas the vehicle 16 is illustrated as being a wheeled vehicle, it will be understood that a tracked vehicle could be used.
In order to rotatably mount the excavating assembly 12 and certain components of the conveyor assembly 14 on the vehicle 16, the excavator 10 is provided with a support assembly 20. In one embodiment the support assembly 20 includes a lower support 22 which is rotatably mounted on the rear section 18 of the vehicle 16. As illustrated in FIGS. 1 and 2, a yoke 24 is provided on the lower support 22 for pivotally supporting a boom assembly 26. Accordingly, the boom assembly 26 can be selectively rotated in a substantially horizontal plane by rotating the lower support 22 with respect to the vehicle 16 on which it is positioned, and can be selectively pivoted in a substantially vertical plane to raise and lower the distal end of the boom assembly 26. As will be discussed further below, various drive mechanisms could be used to selectively rotate and pivot the boom assembly 26, but it is contemplated that in one embodiment a suitable hydraulic system could be used.
The boom assembly 26 serves as a supporting structure for both the excavating assembly 12 and at least a pair of conveyors which make up a portion of the conveying assembly 14. More specifically, the boom assembly 26 includes a proximal section 28 pivotally mounted in the yoke 24 and at least one extendable section 30 that defines a distal end portion 32. In one embodiment the proximal section 28 defines a tubular structure which telescopically receives at least a proximal portion of the extendable section 30 of the assembly 26. As a result, the extendable section 30 can be axially extended and retracted with respect to the proximal section 28 to allow the excavating assembly 12 to be positioned a selected distance from the vehicle 16. It will be understood by those skilled in the art that various drive mechanisms could be used to selectively extend and retract the extendable section 30 of the boom assembly 26, but, as will be discussed below, in one embodiment a hydraulic actuator is provided to accomplish such selected movement of the extendable section 30.
In one embodiment the excavating assembly 12 is mounted proximate the distal end portion 32 of the extendable section 30 of the boom assembly 26. More specifically, in this embodiment the assembly 12 includes a bucket conveyor 34 which is pivotally secured to the extendable section 30. The bucket conveyor 34 includes a plurality of buckets 36 (see FIGS. 5 and 6) that are mounted on a rotating belt 38 such that the buckets 36 can be used to dig or scoop up soil, sand, gravel, or another material, and carry such excavated material to the conveyor assembly 14. In order to facilitate the proper positioning of the bucket conveyor 34 to accomplish the desire excavation and the transfer of excavated material to the conveyor assembly 14, a suitable mechanism is provided for pivotally securing the excavating assembly 12 to the extendable section of the boom assembly 26, such as the support brackets 40a and 40b (see FIG. 3). Further, a suitable actuating mechanism, such as the hydraulic actuator 42, is provided for selectively pivoting the excavating assembly 12. In this regard, it will be understood that various drive mechanisms could be used to rotate the belt 38 of the bucket conveyor 34. However, as will be discussed below, it is contemplated that in one embodiment a hydraulic motor is provided for selectively rotating the belt 38.
As best illustrated in FIGS. 1 and 2, in one embodiment of the excavator 10 the conveyor assembly 14 includes a first conveyor 44 which is supported by the proximal section 30 of the boom assembly 26, and includes at least one extendable conveyor 46 which extends and retracts longitudinally with respect to the first conveyor 44. In this regard, the extendable conveyor 46 is secured to the extendable section 30 of the boom assembly 26 such that the extendable conveyor 46 can be extended and retracted by extending and retracting the extendable section 30 of the boom assembly 26. More specifically, in one embodiment the extendable conveyor 46 is slidably mounted above the first conveyor 44, and the extendable conveyor 46 is attached to the distal end portion 32 of the extendable section 30 of the boom assembly 26 at its distal end. In the drawings the extendable conveyor 44 is illustrated as being slidably received in a housing 48 which at least partially encloses the first conveyor 44, but it will be understood that various supporting frame mechanisms could be used to slidably support the extendable conveyor 46.
As illustrated in FIGS. 1-3, the conveyors 44 and 46 are provided with conveyor belts 50 and 52, respectively, for conveying excavated material received from the excavator assembly 12. In this regard, the extendable conveyor 46 is positioned with respect to the extendable section 30 of the boom assembly 26, and with respect to the excavating assembly 12, such that the belt 52 receives excavated material from the excavator assembly 12 and conveys it to the belt 50 of the first conveyor 44. The belt 50 of the first conveyor 44 then conveys the excavated material to a further conveyor 54 mounted on the vehicle 16, with the further conveyor 54 serving to offload the excavated material from the vehicle 16. In the illustrated embodiment of FIG. 3, the further conveyor 54 is a substantially U-shaped belt conveyor with a conveyor surface capable of movement in either direction along the U-shaped path of the conveyor, and with outlets 56 disposed on opposite sides of the vehicle 16. Those skilled in the art will appreciate that belt conveyors which turn corners in a horizontal plane are often composed of a belt of pivoting slats, and it is contemplated that the conveyor 54 could incorporate such a slatted belt. As illustrated in FIG. 3, the U-shape of the further conveyor 54 allows the proximal end of the first conveyor 44 to be maintained over the conveyor surface of the further conveyor 54 notwithstanding changes in the positioning of the excavating assembly within a substantially 180 degree arc. Further, the two outlets 56 allow for selective offloading of excavated material on either side of the vehicle 16. For example, and as illustrated in FIG. 3, a first truck 58 and conveyor 60 can be positioned on one side of the excavator 10, and a second truck 62 and conveyor 64 can be positioned on the opposite side of the excavator 10. The further conveyor 54 can first be set such that the conveying surface moves in a direction to offload excavated material onto the conveyor 60 such that excavated material is loaded in the truck 58. When the truck 58 has been filled, the further conveyor 54 can be set such that the conveying surface moves in a direction to offload excavated material onto the conveyor 64 such that excavated material is loaded in the truck 62. While this offloading takes place, the excavating assembly 12 can continue operating, and the excavating assembly 12 can be selectively repositioned within the substantially 180 degree arc during such operation.
In FIG. 4 an alternate embodiment of the excavator of the present invention is illustrated at 10′. It will be noted that in the embodiment of FIG. 4 the further conveyor 54′ is a reversible belt conveyor having a belt which travels along a linear path. It will be understood that this alternate conveyor 54′ provides for selective offloading through the opposing outlets 56. However, use of the conveyor 54′ instead of the conveyor 54 does reduce the extent to which the boom assembly 26′, and, thus, the excavating assembly 12′, can be horizontally rotated while unloading continues.
As noted above, various drive systems could be used to drive the various conveyors of the present invention and to rotate and pivot the various components of the invention. However, it is contemplated that a hydraulic drive system could be advantageously used. An example of a suitable hydraulic drive system 66 is schematically illustrated in FIG. 7. The system 66 includes a hydraulic pump unit 68 that includes one or more hydraulic pumps which are driven by either the internal combustion engine of the vehicle 16 or another power source, and includes a control unit 70 for selectively controlling the operation of various hydraulic motors and actuators. As noted above, the support assembly 20 is rotatably mounted on the rear section 18 of the vehicle 16. As illustrated in FIG. 7, a first hydraulic motor 72, along with a suitable gear mechanism 74, is provided to accomplish the selective rotation of the support assembly 20. As illustrated, the hydraulic motor 72 is operatively connected to the control unit 70 to allow the operator of the excavator 10 to control the selective positioning of the boom assembly 26. Further, a hydraulic actuator 76 is operatively connected to the control unit 70 to allow the operator to selectively extend and retract the extendable section 30 of the boom assembly 26. Moreover, it will be noted that a hydraulic actuator 73 is provided for selectively pivoting the proximal section 28 of the boom assembly 26 thereby selectively raising or lowering the distal end portion 32 of the extendable section 30.
As noted above, the hydraulic actuator 42 is provided for selectively pivoting the excavating assembly 12, and such actuator 42 is operatively connected to the control unit 70 to facilitate such selective pivoting by the operator. Further, a second hydraulic motor 78 is operatively connected to the control unit 70 to selectively drive the bucket conveyor 34 of the excavating assembly 12. It will also be noted that a third hydraulic motor 80, a fourth hydraulic motor 82, and a fifth hydraulic motor 84, are operatively connected to the control unit 70 and selectively drive the first conveyor 44, the extendable conveyor 46, and the further conveyor 54, respectively. As illustrated in FIGS. 1-4, in one embodiment, the vehicle 16 is provided with a secondary cab 86 in which an operator can sit and operate the excavator 10.
In FIGS. 8A and 8B an alternate embodiment of the excavator of the present invention is illustrated generally at 10″. It will first be noted that in this alternate embodiment the boom assembly 26″ incorporates an intermediate extendable section 88, at least a portion of which is telescopically received in the proximal section 28″, and which telescopically receives at least a portion of the extendable section 30″ of the boom assembly 26″. The use of the intermediate extendable section 88 allows for greater extension of the boom assembly 26″ without compromising the strength and stability of the boom assembly 26″. Further, instead of the two conveyors 44 and 46 of the excavator 10, the excavator 10″ utilizes a single extendable conveyor 46″. As illustrated, the conveyor 46″ is a belt conveyor having a belt 52″ that is rotatably supported by at least one, and in the illustrated embodiment two, movable rollers 90 which are moveable between a first position proximate the upper conveying surface of the conveyor 46″ and a second position more displaced from the upper conveying surface of the conveyor 46″ such that tension on the belt 52″ can be maintained as the boom sections 30″ and 88 are selectively extended and retracted.
In light of the above it will be understood that the excavator of the present invention offers significant advantages over the prior art. Given the mounting of the excavator assembly 12 on the boom assembly 26, and the pivotal mounting of the boom assembly 26 on the vehicle 16, the excavator assembly 12 can be continuously moved over a wide area around the vehicle 16 as the excavation operation continues. Further, given the extendable conveyor 46, the excavating operation and the conveying of the excavated material off of the vehicle 16 can continue simultaneously as the excavating assembly 12 is repositioned to excavate new areas. Moreover, the further conveyor 54 facilitates the offloading of the excavated material from the vehicle 16 and the loading of the excavated materials into transport vehicles.
While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept.