1. Field of the Invention
Embodiments of the present invention generally relate to a construction equipment attachment for aligning a lead and hammer with an object to be driven. The invention is particularly suitable for driving objects such as a timber piles, steel piles, pipe piles, steel sheet piles, h-beam and the like, into the earth.
2. Description of the Related Art
Buildings, bridges and other structures often require pilings driven into the earth in order to either reach strata suitable for supporting the load of the structure or to a depth that the frictional force between the earth and the pile is sufficient to safely support the structure. For many larger structures, the pilings are driven through the soil to the underlying bedrock, which may lie a considerable distance below the earth's surface. To reach such depths, piles are driven utilizing heavy construction equipment that can deliver blows exceeding 7 tons per impact.
The suspended lead 102 relies on gravity and one or more tethers 116 to maintain a vertical orientation and provides a guide for both the hammer 104 and the piling 108 to be driven into the ground 110. The hammer 104 is typically powered by air or hydraulics to provide reciprocating blows to the top of the piling 108 to force the piling into the ground 110. Although the lead 102 may be tethered at its lowered end by a cable or linkage 116 to the crane 106 to maintain the alignment of the lead 102 with the piling 108, it is difficult to maintain the hammer 104 and piling 108 on a coaxial orientation. If the hammer 104 is not maintained in a true coaxial orientation with the piling 108, the piling will be impacted at an angle relative to the centerline of the piling. Thus, the full force of each hammer blow will not be complete transmitted into a force directing the piling 108 into the ground 110.
The load bearing capability of the piling may be determined at the construction site by counting the number of hammer blows of a known force required to drive the piling a unit distance into the ground. Thus, if the piling and lead are misaligned and the full force of the hammer blow does not force the piling downward, the number of blows per unit distance that the piling is driven will erroneously indicate piling load bearing capacity as being greater than the true load bearing capacity of the piling. False load bearing information may result in unwanted settling of structures built on the pilings, or even catastrophic structural failure.
Another major challenge when using conventional suspended leads is the avoidance of overhead power lines and other overhead obstacles. Power lines at construction sites make it difficult to maneuver the crane and lead into operating position, and in some instances, must be removed to provide enough clearance for the crane to adequately support the lead or support the head over the planned pile position. Removal of these obstacles presents a major and expensive challenge to contractors charged with driving the pilings.
Therefore, there is a need for an improved pile driving device.
Embodiments of the invention generally provide a construction equipment attachment for aligning a lead and hammer with an object to be driven, such as a timber piles, steel piles, pipe piles, steel sheet piles, h-beam and the like. In one embodiment, the attachment includes a hammer slidably coupled to a lead, a lead mounting assembly and a hydraulic actuator coupled to the lead and the lead mounting assembly. The hydraulic actuator is adapted to control the orientation of the lead relative to the lead mounting assembly.
In another embodiment, an attachment for a self-propelled heavy construction machine is provided. The attachment allows for the alignment of a lead with a workpiece utilizing existing hydraulic fluid control ports of the machine.
In yet another embodiment, a self-propelled heavy construction machine having a lead positionable along three axes is provided.
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
The invention generally provides an improved pile driving attachment that is adapted to readily attach to an excavator or other heavy construction machine. The invention facilitates alignment between a hammer of the pile driving apparatus and a workpiece, such as timber piles, steel piles, pipe piles, steel sheet piles, h-beam and the like, so that the force from the hammer is efficiently utilized to drive the workpiece. Moreover, the invention allows for pile driving operations to be conducted in and around crowded construction sites, including those with overhead obstacles, which make operation of conventional pile driving equipment difficult, unsafe and/or costly to operate.
The self-propelled machine 250 includes at least one hydraulic pump 252 and control manifold 248 providing control of hydraulic fluid through at least eight ports 254A, 254B, 256A, 256B, 258A, 258B, 260A, 260B. The self-propelled machine 250 generally has at least a 50-ton weight and is configured to accept a boom 262, for example, in an excavator configuration. Self-propelled machines 250 having hydraulic ports providing fluid control for various attachments to the machines 250 are well known. In one embodiment, the self-propelled machine 250 is a Model 345B Excavator available from Caterpillar, Inc., of Peoria, Ill. It is contemplated that self-propelled machines may alternatively comprise other heavy construction equipment adapted for use with the pile driving attachment 200.
The boom 262 is coupled at a first end 264 to the self-propelled machine 250 and to the pile-driving attachment 200 at a second end 266. The boom 262 has a first axis of rotation 212 defined at the first end 264. As the boom 262 is raised or lowered, the pile driving attachment 200 is moved relative to the self-propelled machine 250 relative to the first axis of rotation 212. At least one first cylinder 268 is coupled to the ports 254A-B to control the rotation of the boom 262 relative to the first axis of rotation 212. Hydraulic lines coupled to the ports 254A-B have been omitted from the Figures for clarity.
The second end 266 of the boom 262 is coupled to the lead mounting assembly 202 of the pile driving attachment 200. A second cylinder 270 is coupled between the lead mounting assembly 202 and the boom 262. The second cylinder 270 is coupled to the pump 252 through the ports 256A-B to control the rotation of the lead mounting assembly 202 around a second axis of rotation 214 defined at the attachment of the second end 266 of the boom 262 to the lead mounting assembly 202. In one embodiment, the second axis 214 is orientated substantially parallel to the first rotational axis 212.
The lead 204 is rotationally coupled to the lead mounting assembly 202. A third cylinder 272 is coupled between the lead 202 and the lead mounting assembly 202. The third cylinder 272 is coupled to the pump 252 through the ports 258A-B to control the rotational orientation of the lead 204 relative to the lead mounting assembly 202 around a third rotational axis 216. In one embodiment, the third axis 216 is orientated substantially perpendicular to the first and second rotational axes 212, 214. The third cylinder 272 may alternatively be a hydraulic actuator, lead screw or other actuator, hydraulic or electric, suitable for rotating the lead 202 and hammer 204.
Referring to
The mounting bracket 350 includes a first side 304 and a second side 302. The first side 304 of the mounting bracket 350 includes a first hole 320 and a second hole 322. The holes 320, 322 are generally formed in a spaced-apart relation and have substantially parallel centerlines. The first hole 320 is coaxial with the second axis of rotation 214 and facilitates coupling of the mounting bracket 350 to the second end 266 of the boom 262 by a pin or shaft (not shown).
The second hole 322 is positioned to facilitate coupling of the second cylinder 270 to the mounting bracket 350. Generally, the second hole 322 is located to allow the lead 202 to be rotated into an orientation below the boom 262 substantially parallel to the ground (as depicted in
The second side 302 of the lead mounting bracket 202 includes a third hole 324. The third hole 324 has a centerline substantially perpendicular to the centerlines of the first and second holes 320, 322, and is coaxial with the third axis of rotation 216.
The shaft 354 is disposed through third hole 324 and holes 326, 328 formed through the mounting plate 352 and lead 204. The shaft 354 is welded or otherwise fastened to one of the lead mounting assembly 202 or lead 204. In the embodiment depicted in
The lead 204 may additionally include a pair of retaining tabs 370 that capture the mounting plate 354 to the lead 204. The tabs 370 are spaced from the lead 204 to facilitate rotation of the mounting plate 354.
Referring back to
In another embodiment, the hammer 206 may be laterally shielded by a cage 240. The cage 240 is generally fabricated from steel or strong material, and is configured to move along the lead 204 with the hammer 206. The cage 240 may include an integral ladder 242 having a parallel orientation relative to the lead 204. In the embodiment depicted in
Alternatively, the cage 240 may be coupled to the lead 204. the cage 240 extends along the length of the lead 204 so that the hammer 206 is shielded at every position along the lead 204.
In yet another embodiment, the lead 204 may include a plurality of holes 284 (shown in phantom in
Moreover, as the winch 230 can position the hammer along the lead 204 while the lead 204 is in a vertical position, the lead 204 does not have to be elevated in order for the hammer 206 to be set upon a piling. This allows the pile driving attachment 200 to be operated with minimal clearance above the piling 802.
Once the hammer 206 is set upon the piling, the hammer 206 and lead 204 are aligned with the piling 802 by rotating the lead 204 about the second and third axes 214, 216. The hammer 204 is then activated to drive the piling 802 into the ground 606. Although the piling 802 shown in
Thus, a piling driving apparatus has been provided having an improved lead alignment apparatus. The lead alignment apparatus is advantageously suited for attachment to existing heavy construction equipment, such as an excavator, utilizing the hydraulics provided by that equipment to position the lead without additional pumps or motors. Moreover, the lead may be readily aligned with a piling in any orientation, such that the hammer provides a driving force coaxial with the pile. Additionally, the lead alignment apparatus may be rotated substantially horizontal to the ground, thereby allowing the pile driver to safely move in a job site having tight clearances between overhead and vertical obstructions.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
This application is a continuation application of co-pending U.S. patent application Ser. No. 10/840,136, filed May 6, 2004, which is incorporated by reference herein.
Number | Date | Country | |
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Parent | 10840136 | May 2004 | US |
Child | 11674510 | Feb 2007 | US |