Spring-Loaded Sod Cutter For Vibratory Plow
A sod cutting blade pivotally supported on a plow assembly frame such that the sod cutting blade is able to pivot and pass over an obstruction when encountered during a plowing operation. The plow assembly has a spring that is used to bias the sod cutter into the ground.
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CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of provisional patent application Ser. No. 61/770,024, filed on Feb. 27, 2013, the entire contents of which are incorporated herein by reference.
The present invention relates generally to the field of utility installation and in particular to the use of plows for the installation of underground utilities.
The present invention is directed to a system for installing a utility underground. The system comprises a mobile power source comprising a work machine frame and a plow assembly connected to the power source. The plow assembly comprises an arm pivotally connected to the work machine frame at a first end of the arm, a shaker box connected to a second end of the arm, a plow blade connected to the shaker box, and a pivotal sod cutting member supported by the arm between the first end of the arm and the second end of the arm ahead of the plow blade. The sod cutting member has a cutting length less than a length of the plow blade and pivots when the sod cutting member engages an underground obstruction. A biasing member is connected to the sod cutting member and the arm to bias the sod cutting member into the ground.
BRIEF DESCRIPTION OF THE DRAWINGS
In many instances, this type of machine is used to install services in nicely landscaped areas with established turf. In these instances, the vibratory plow machines 10 commonly run a sod cutter 26 in front of the plow blade 22 to pre-cut the sod 28 in front of the plow blade to minimize the turf damage done as the vibratory plow machine operates. The sod cutter 26 provides a clean cut in Bermuda grass or similar grasses with rhizomes, or “runners” that spread out on the surface of the ground and helps to prevent a pulling and uprooting of the grass as the blade passes. Sod cutter types that have been used include a narrow fixed blade or a rolling disc to cut the sod.
One problem that can be encountered with the current sod cutters is when an obstacle 30 such as a stone or tree root exists at or close to the surface of the ground. This type of obstacle can damage the sod cutter 26, and/or cause the shaker box 20 to be lifted up as the sod cutter passes over the obstacle, resulting in an inconsistent burial depth for the installed utility.
In use, the device functions as follows. The sod cutter 32 extends into the surface of the ground 28 (typically about 3″-6″) and cuts the sod in front of plow blade 22. Springs 38 are attached to a device frame 40 and to an attachment point 42 above the pinned pivot 36 on the blade 32. In this configuration, the spring 38 provides a measure of preload on the blade 32 to keep it from freely pivoting and moving backward. The preload on the blade 32 is sufficient to allow the blade to cut through normal sod and vegetation as is found in an established lawn without pivoting backward. When an obstacle of sufficient size, such as a large stone or tree root is encountered, the preload on the blade 32 is overcome and the blade may pivot back allowing the sod cutter to pass over the obstacle without damage and without causing the shaker box to be lifted up relative to the ground surface. After passing over the obstacle 30 (
The leading edge 44 of the sod cutter 32 will have a semi-sharpened leading edge comparable to a knife blade, and the toe 46, or leading point, of the sod cutter will extend forward of the pivot point 36 as shown in
The present invention is also directed to a method of using the above described devices to cut a trench in the Earth and install a utility.
Various modifications can be made in the design and operation of the present invention without departing from the spirit thereof Thus, while the principal preferred construction and modes of operation of the invention have been explained in what is now considered to represent its best embodiments, which have been illustrated and described, it should be understood that the invention may be practiced otherwise than as specifically illustrated and described.
1. A system for installing a utility underground, the system comprising:
- a mobile power source comprising a work machine frame;
- a plow assembly connected to the power source, the plow assembly comprising: an arm pivotally connected to the work machine frame at a first end of the arm; a shaker box connected to a second end of the arm; a plow blade connected to the shaker box; a pivotal sod cutting member supported by the arm between the first end of the arm and the second end of the arm ahead of the plow blade, wherein the sod cutting member has a cutting length less than a length of the plow blade and pivots when the sod cutting member engages an underground obstruction; and a biasing member connected to the sod cutting member and the arm to bias the sod cutting member into a ground surface.
International Classification: E02F 5/02 (20060101); E02F 9/00 (20060101);