Background of the Invention
This invention pertains to a shearing device, and, more particularly, relates to a vehicle mounted tree shearing device.
It is oftentimes desirable that a relatively simple device be available to sever objects such as trees. While trees might be individually cut, as by a saw, this is both time and labor consuming, and hence it is desirable that a device be provided to quickly and safely sever trees with the device preferably being relatively simple both in construction and operation.
While devices have heretofore been suggested and/or utilized for cutting or severing trees, such devices have not proved to be completely successful due to such diverse reasons as being unduly complicated, of expensive construction, unreliable in operation, and/or being operationally slow.
U.S. Pat. No. 2,793,486 shows, for example, a harvester for stalk type crops, such as tobacco, wherein stalks are guided into a recess formed by spaced arms, but the device utilizes a driven rotary type cutter. In like manner, U.S. Pat. No. 3,364,964 shows a severing apparatus for cutting trees and the like, but a cutting disk that comprises a horizontal circular blade is utilized.
U.S. Pat. No. 3,529,641 shows a tree shearing assembly, but the cutter blade utilized is moved by a cylinder and piston arrangement. In like manner, U.S. Pat. Nos. 3,482,614, 3,626,477 and 3,627,002 show felling or severing devices wherein a member is pivoted by a cylinder and piston arrangement, while U.S. Pat. No. 3,612,115 shows a pivot member with a saw element thereon.
U.S. Pat. Nos. 2,529,934 and 2,214,334 show a cutter attachment for tractors wherein a pair of cutters are pivoted for movement toward one another, but such movement depends upon movement of a guide plate to cause both cutters to be simultaneously moved toward one another.
Thus, the problem of providing a relatively simple yet dependable shearing device that does not depend upon closing movement between a pair of cutters, saw elements, and/or power driven cutters has remained unsolved at least in some appreciable measure.
Summary of the Invention
This invention provides a relatively simple yet dependable device that is well suited for severing of objects such as trees. The shearing device of this invention does not require driven cutting elements, but instead depends only upon continued movement of the device after tree contact has been established in order to sever the tree.
It is therefore an object of this invention to provide an improved shearing device.
It is another object of this invention to provide an improved shearing device that is simple yet dependable.
It is still another object of this invention to provide an improved shearing device that is useful for severing trees.
It is yet another object of this invention to provide an improved shearing device that severs an object by movement of the device and does not require power driven cutters.
It is still another object of this invention to provide an improved shearing device that is vehicle mounted and requires only the movement of the vehicle to sever a tree in contact with the shearing device.
With these and other objects in view, which will become apparent to one skilled in the art as the description proceeds, this invention resides in the novel construction, combination, and arrangement of parts substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention are meant to be included as come within the scope of the claims.
Brief Description of the Drawings
The accompanying drawings illustrate a complete embodiment of the invention according to the best mode so far devised for the practical application of the principles thereof, and in which:
FIG. 1 is a front perspective view of a tractor having the shearing device of this invention mounted thereon;
FIG. 2 is a plain view of the shearing device of this invention;
FIG. 3 is a front elevation view of the shearing device of this invention;
FIG. 4 is a side elevation view of the shearing device of this invention;
FIG. 5 is an enlarged sectional view taken along line 5--5 of FIG. 2, but with the shear structure position as shown in FIG. 8.
FIGS. 6, 7, and 8 are plan views showing, somewhat in schematic, showing initial tree contact, partial severing of a tree, and complete severing of the tree utilizing the shearing device of this invention.
Description of the Preferred Embodiment
Referring now to the drawings, shearing device 9 of this invention is shown mounted on a vehicle, or tractor 11. Tractor 11 may be conventional and includes a front portion 13 to which the shearing device 9 is preferably mounted. As indicated in FIG. 1, tractor 11 can include a conventional movable frame 15 that can be raised and lowered by means of hydraulic cylinder assemblies 17. By mounting the shearing device 9 on movable frame 15, the shearing device can be vertically positioned or adjusted as desired, as well known in the art. As also indicated in FIG. 1, a guide and protective bar 19 is preferably mounted on tractor 11 to direct a severed tree to the side of the tractor 11.
Shearing device 9 includes a frame member 21 which has arms 23 and 25 which extend in the same predetermined direction. As shown in FIG. 1, when mounted on the forward portion of the tractor, arms 23 and 25 extend forwardly from the tractor to receive a tree to be severed between the arms as the tractor is moved forwardly.
Arm 23 is preferably a flat plate of triangular configuration, while arm 25 may consist of a pair of vertically spaced plates 26, 28 of substantially rectangular configuration. Arms 23 and 25 have facing edges 27 and 29, respectively, defining a recess therebetween. As shown best in FIG. 2, edges 27 and 29 are preferably substantially parallel with respect to one another to form a substantially rectangular recess 30 therebetween. As shown in FIGS. 2 and 3, a plurality of protuberances 31 may be spaced along arm 25 near edge 29. While not shown in detail, it should be understood the frame member 21 may be mounted on the tractor for some slight lateral shifting. By so doing the edge 29 may be operated as an anvil against a tree when the frame shifts during a shearing operation. The shifting feature may be locked out.
Frame member 21 also includes a rear mounting portion 33 extending substantially normal to arms 23 and 25 and utilized for mounting the frame member on the front of a tractor or the like. Mounting of frame member 21 on a tractor is conventional.
Near the free end of the arm 23 (that is, at the end opposite to mounting portion 33), is mounted a shoulder 35. Shoulder 35 on arm 23 acts as a stop to define the normal, or open, position of pivot member 39 mounted on arm 23.
Pivot member 39 includes a flat plate 41 contiguous to the upper surface of arm 23 and preferably has strengthening ribs 43 protruding upwardly therefrom. A cross rib 44 may also be provided to add strength to the pivot member. A guide 45 extends from one of the ribs 43, and as shown in FIGS. 2 and 3, this guide can extend into the slot between the two spaced plates 26, 28 forming arm 25, if desired.
One end of pivot member 39 is mounted for pivotal movement with respect to arm 23 by means of pivot bolt 47. Spring 49 connected between arm 23 and pivot member 39 biases the pivot member to the normal, or initial, position so that one side of the pivot member is in contact with stop shoulder 35.
A cutter or severing edge 51 is connected to pivot member 39 near the free end thereof (i.e., the end opposite to that in contact with pivot bolt 47). As shown best in FIG. 3, in the normal position cutting edge 51 extends partially across recess 31 near the opening in the recess formed by arms 23 and 25, so that a tree or other object received within the recess will come into contact with edge 51. Guide 45 prevents an object such as a tree from bypassing cutter 51 when such an object is moved rearwardly within the recess.
In operation, the shearing device of this invention is preferably vehicle mounted, such as on a tractor as indicated in FIG. 1. The tractor is then moved forwardly, and the tree or other object to be severed is guided into recess so that the tree comes into contact with cutter edge 51 of pivot member 39. In some instances the tree may first contact guide 45. This initial contact is shown in FIG. 6 of the drawings. As the tractor continues to move forward, the tree causes the pivot member 39 to pivot about pivot bolt 47 so that cutter edge 51 is moved in an arc toward edge 29 of arm 25. Since the tree is at this time stationary, the tree will be between the cutter and edge 29 and will be severed as continued movement of the vehicle in the predetermined direction (forwardly, where attached to a front of a tractor) is continued.
FIG. 7 shows a tree partially severed by movement of the vehicle, and FIG. 8 shows complete severing of the tree as the cutter 51 is brought into a position contiguous to edge 29 of arm 25. Due to the bias on the pivot member 39, after the tree has been severed, the pivot member 39 will be automatically urged back to its initial, or normal, position by means of spring bias 49. After pivot member 39 has regained its normal position, the shearing device is, of course, ready to be brought into contact with another object to sever the same.
Since the object to be severed is continuously urged by cutting edge 51 toward and in contact with edge 29 of arm 25, the cutting of each object is accomplished in substantially the same manner, with the result that the severed object is caused to fall rearwardly and into contact with guide and protective bar 19 so that the severed trees fall consistently to the same side, so that a consistent manner and direction of fall can be therefore maintained the same.
In view of the foregoing, it is apparent that this invention provides an improved shearing device that is particularly useful for shearing of trees and the like.