JPH07106108B2 - Tree felling machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tree felling machine used for felling standing trees.

2. Description of the Related Art As a tree cutting machine that cuts a standing tree with a cutting blade, for example, a "tree cutting device" disclosed in Japanese Utility Model Publication No. 58-6279 is known.

This "tree cutting device" is composed of a shearing head unit equipped with a pair of shearing blades that are opened and closed by hydraulic means, and at the time of tree cutting, the shearing head unit is fixed to the lower end of the mast on the boom while the tree trunk is fixed. A gripper to be gripped is attached to the upper side of the mast, and the main blade of the tree is gripped by the gripper while driving the shear blade of the shear head unit to cut the main trunk of the tree.

Problem to be Solved by the InventionWhen driving a shearing blade to bite a cutting edge into a tree, with the wedge effect due to the biting of the cutting edge, a phenomenon occurs in which the tree is vertically stretched at the cutting position, In the prior art, over the entire cutting process, since the distance between the shear blade and the gripper gripping the tree is cut into the tree, the tree is stretched between the shear blade and the gripper. As the cutting edge is accelerated and the cutting edge is accelerated, the compressive stress acting on the tree part held by the shear blade and the gripper gradually increases, and this compressive stress acts on the tapered surface of the cutting edge to obstruct the cutting. Therefore, there is a drawback that a strong force is required to continue the cutting work.

Further, in the prior art, the shearing head unit including a pair of shearing blades and the gripper for gripping the tree trunk are substantially fixed to the mast on the boom, but the boom of the work vehicle is usually A function of swinging an attachment such as a mast attached to the tip portion in the left-right direction is not provided. Therefore, in a situation where the boom of the work vehicle cannot but cross the fall line of the sloping terrain due to conditions such as the vegetation state and topography of the trees, the mast should be parallel to the trees that have grown along the direction of the action line of gravity. There is a drawback that it is difficult to position and perform normal logging operations.

Therefore, it is an object of the present invention to solve the above-mentioned drawbacks of the prior art and to provide a tree felling machine capable of smoothly and easily felling a tree.

Means for Solving the Problems The first invention, in order to achieve the above-mentioned object, is to provide a pair of cutting blades having a cutting edge with an upper surface taper on one side of a lower end portion of a columnar support and hydraulically opening and closing the tree trunk. A gripper for gripping is attached to the cutting blade mounting side of the support so as to be slidable along the longitudinal direction of the support.

Further, in the second invention, a boom mounting bracket is rotatably mounted on the side above the center of gravity in the longitudinal direction of the columnar support and opposite to the cutting blade mounting side.

Action In the first aspect of the invention, the pair of cutting blades provided on one side of the lower end of the columnar support is hydraulically driven to be slidably attached to the side where the cutting blades are mounted on the support along the longitudinal direction of the support. When the cutting edge having the upper surface taper is made to bite into the tree gripped by the gripper, a phenomenon occurs in which the tree is stretched at the cutting position due to the wedge effect due to the biting of the cutting edge.

The gripper that grips the tree slides upward along the support according to the stretching of the tree, so the compressive stress does not act on the tree portion held by the cutting blade and the gripper, and the tapered surface of the cutting edge Since the external force that prevents biting does not work, it is possible to easily perform cutting work related to felling trees.

Further, in the second invention, the columnar support provided with a pair of cutting blades that are opened and closed by hydraulic pressure on one side of the lower end portion is above the position of the center of gravity in the longitudinal direction, and on the cutting blade mounting side. Since it is attached to the boom via a boom mounting bracket that is rotatably mounted on the side opposite to the side, the support can swing freely in the left-right direction with respect to the boom, and moreover, above the center of gravity. Since it is rotatably supported, it is always maintained in a vertical state in the left-right direction of the boom due to its own weight.

Therefore, even when the boom crosses the fall line of the sloping terrain, it is easy to position the support in parallel with the vertically grown tree, and the positioning work related to the felling of the tree is performed. It can be done very smoothly.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a side view showing a tree cutting machine according to one embodiment, and FIG. 2 is a cutting line A-B-C of the same tree cutting machine shown in FIG.
FIG. 3 is a cross-sectional view seen from below along the line -D, and FIG. 3 is a rear view showing the tree felling machine, and the tree felling machine 1 is generally rectangular as shown in FIGS. 1 and 2. It is composed of a columnar support 2 having a cross section, a pair of cutting blades 3 and 4, a hydraulic device 5 for driving the cutting blades 3 and 4 to open and close, a gripper 6 and a boom mounting bracket 7.

The pair of cutting blades 3 and 4 penetrates the inside of the base of the hollow blade housing 10 fixed to the lower end of the columnar support 2 with the cutting edges 8 and 9 facing each other in the same horizontal plane. The blade housing 10 is rotatably attached to the shafts 11 and 12 on which the cutting blades 3 and 4 are attached.
A concave notch 13 is formed on one side, and cutting blades 3 and 4 having upper surface cutting edges 8 and 9 are projected to one side of the lower end of the columnar support 2. The positional deviation of the cutting blades 3 and 4 in the vertical direction is prevented by a collar (not shown) that is surrounded by the shafts 11 and 12.

On the outside of the bases of the cutting blades 3 and 4, the other ends of the link members 16 and 17 pivotally attached at one end to both ends of a pressing piece 15 fixed to the tip of the piston rod 14 of the hydraulic device 5 in a T shape. While being pivotally mounted, the cylinder 18 of the hydraulic system 5 is
Is fixed to the support members 21 and 22 which are a part of the side wall of the blade housing 10 via the link member, and the piston rod 14 is contracted and expanded by operating the hydraulic device 5.
The cutting blades 3 and 4 are opened and closed through a link mechanism composed of 16, 17 and the like. In FIG. 2, the closed state of the cutting blades 3 and 4 is shown by a solid line, while the open state of the cutting blades 3 and 4 is shown by a chain double-dashed line. And in this embodiment, the cutting blade
The cutting edges 8 and 9 of 3 and 4 are curved slightly inward, and the cutting blades 3 and 4 are closed between the facing cutting edges 8 and 9 as shown in FIG. The spindle-shaped gap is formed.

The columnar support 2 has a rectangular cross section in the axial direction, and a gripper unit 23 having a gripper 6 in the longitudinal direction thereof.
Are polymerized to form a ring that is slidable and non-rotatable in the axial direction of the columnar support 2.

FIG. 5 is a plan view showing the gripper unit 23, and a fitting hole 25 which is loosely fitted along the cross-sectional shape of the columnar support 2 is formed in a substantially central portion of the base body 24 of the gripper unit 23. On the other hand, gripper pivot holes 26, 26 are provided at both ends on one side of the base body 24, and cylinder pivot holes 27, 27 are provided at both ends on the opposite side to the gripper pivot holes for one gripper. In the hole 26 and the cylinder pivot hole 27, the curved gripper 6 and the end of the cylinder 29 of the hydraulic device 28 are respectively provided with shafts 30 and 3 provided with a fall-preventing means such as a set screw or a split pin.
It is rotatably pivoted through 1. Also, hydraulic system 2
The tip of the piston rod 32 of 8 has a shaft 33 on the curved portion of the gripper 6.
The gripper 6 is opened and closed by operating the hydraulic device 28 to expand and contract the piston rod 32. In FIG. 5, the closed state of the gripper 6 is shown by a solid line, while the open state of the gripper 6 is shown by a chain double-dashed line.

In the gripper unit 23 having such a configuration, the extension direction of the gripper 6 is made to coincide with the attachment direction of the cutting blades 3 and 4, and the attachment side of the gripper 6 in the base body 24 is alternately reversed to the left and right to make the first It is looped around the columnar support 2 in the state shown in the figure. That is, in FIG. 3 showing the tree felling machine 1 from the rear side, the lowermost gripper unit 23, the third lower gripper unit 23 and the uppermost gripper unit 23 are located on the right side when viewed from the rear side.
On the other hand, the gripper unit 23 at the second stage from the bottom and the gripper unit 23 at the second stage from the top are provided with the gripper 6 on the left side when viewed from the back.

Further, FIG. 6 shows a gripper unit arranged in this way.
FIG. 23 is a plan view showing a superposed state of 23, each gripper unit
It can be seen that when the gripper 6 included in 23 is closed, the tips of the grippers 6 slightly overlap each other.

The columnar support 2 having a rectangular cross section is further provided with a rectangular tubular body 34 having flange-shaped flanges 35 and 36 formed on both ends thereof, and the columnar support 2 is cut at the rectangular tubular body 34. A boom mounting bracket 7 integrally fixed to the turntable 37 is mounted on the side opposite to the mounting side of the blades 3 and 4. That is, a rotating pin 39 having a flange-shaped flange 38 at one end is penetrated through the substantially center portion of the rotating plate 37.
Is a rectangular tubular body that penetrates the rectangular tubular body 34 and the columnar support 2 and is located above the center of gravity G in the longitudinal direction of the columnar support 2.
34 and the columnar support 2 are rotatably supported, and an annular retaining member 40 is detachably attached to the tip thereof. Further, a rotation preventing means (not shown) by concave and convex fitting is provided on the contact surface between the turntable 37 and the rectangular tubular body 34, and as shown in FIG. Rectangular tubular body against
And the relative rotation angle of the columnar support 2 is limited to a predetermined value θ (15 ° in this embodiment).

On the other hand, boom mounting holes 41 and 42 are provided at the upper and lower ends of the boom mounting bracket 7, and a boom shaft 43 and a piston rod 44 from a hydraulic device provided on the boom shaft 43 are provided in the respective holes. The tip portion is rotatably mounted, and the felling machine 1 swings in the front-back direction with respect to the boom shaft 4 by the expansion and contraction of the piston rod 44, that is, in the left-right direction in FIG. You can

Further, the upper end of the columnar support 2 having a rectangular cross section has a fourth
A guide piece 45 as shown is looped. A fitting hole 46 that fits along the cross-sectional shape of the columnar support 2 is provided at a substantially central portion of the guide piece 45, and a concave notch 47 having a vertical taper is formed on one side thereof. Further, a through hole for press-fitting a retaining pin 48 for preventing the positional displacement and the disengagement when the guide piece 45 is looped to the columnar support 2.
49 is provided so as to cross the fitting hole 46.

As is apparent from the above configuration, when assembling or reassembling the tree felling machine 1, first, two sets of gripper units 23 to be attached to the columnar support 2 below the rectangular tubular body 34 are installed. The extension direction of the gripper 6 matches the attachment direction of the cutting blades 3 and 4, and the attachment side of the gripper 6 in the base body 24 is alternately inverted to the left and right, so that the columnar support 2 is looped.

Further, depending on the case, the gripper 6 and the hydraulic device 28 may be attached to both sides of the base body 24.

Next, the rectangular tubular body 34 is looped around the columnar support 2, and the turntable 37 integrated with the boom mounting bracket 7 is attached to the side of the columnar support 2 opposite to the side where the cutting blades 3 and 4 are attached. . It should be noted that the turntable 37 is rotatable with respect to the rectangular tubular body 34 and the columnar support 2 via a rotating pin 39 penetrating the rectangular tubular body 34 and the columnar support 2 (however, a predetermined value θ Fixed range),
The turning pin 39 is prevented from falling off by mounting the retaining member 40. With the lower two sets of gripper units 23 and the rectangular tubular body 34 mounted on the columnar support 2, between the upper surface of the gripper unit 23 and the flange portion 36 of the rectangular tubular body 34 in the second stage from the bottom. Has a gap S at least larger than the thickness of the cutting blades 3 and 4, and these gripper units 23 are slidable in the vertical direction within this stroke range.

Next, in the columnar support 2, three sets of gripper units 23 to be attached to the upper side of the rectangular tubular body 34 are attached to the gripper 6
The extension direction of the match the mounting direction of the cutting blades 3 and 4,
Further, the gripper 6 mounting side of the base body 24 is looped around the columnar support 2 such that the gripper 6 mounting side is alternately reversed, and the guide piece 45 has the concave cutout portion 47 aligned with the gripper 6 mounting direction. In this way, the retaining pins 48 are pressed into place and fixed to the columnar support 2. In the state where the upper three sets of gripper units 23 and the guide pieces 45 are mounted on the columnar support body 2, a gap S is formed between the upper surface of the uppermost gripper unit 23 and the lower surface of the guide pieces 45 as described above. In this stroke range, the gripper units 23 are slidable in the vertical direction.

The tree felling machine 1 assembled in this manner is mounted on the boom of the work vehicle via the boom mounting bracket 7.

Hereinafter, the felling work using the tree felling machine 1 will be described.

First, the work vehicle is appropriately approached to the tree to be felled to operate the boom shaft 43, and the tree felling machine 1 attached to the tip of the boom shaft 43 is roughly positioned. Again, since the tree felling machine 1 is rotatably mounted above the center of gravity position G via the boom mounting bracket 7,
Due to its own weight, it maintains a vertical state in the left-right direction of the boom. Therefore, even when the boom shaft 43 crosses the fall line of the sloping terrain, it is not necessary to position the tree grown in the vertical direction in the left-right direction. As described above, the boom shaft 43 does not have a rotational degree of freedom about the axis, and conventionally, in order to perform felling work on a sloping ground, the boom shaft 43 is positioned in the left-right direction by making it parallel to the fall line. Besides that, the approach direction of the work vehicle was extremely limited due to the vegetation state of the trees, the terrain, etc., but in this embodiment there is no hindrance even if the boom shaft 43 crosses the fall line of the sloping terrain, The positioning work can be performed extremely smoothly.

Next, the guide piece 45 of the tree felling machine 1 is brought into contact with the trunk of the tree to be felled, and the hydraulic device on the boom shaft 43 is operated to extend and retract the piston rod 44, thereby shaking the tree felling machine 1. Move it to position in the front-back direction.

After the positioning is completed, the hydraulic device 28 of each gripper unit 23 is driven in conjunction to operate the piston rod 32 to close the gripper 6, and the gripper 6 grips the tree. As shown in FIG. 1 and FIG. 3, the left and right grippers 6 are arranged at intervals in the vertical direction, so that the left and right grippers 6 are bent into a tree held by the left and right grippers 6 adjacent in the vertical direction. The moment is applied, and the tree can be more reliably gripped as compared with the conventional gripper mechanism that is simply arranged in parallel facing each other. The hydraulic device 28 of the gripper unit 23
May be connected to the same hydraulic power source so that all of them are operated in synchronization, and the hydraulic devices 28 of the upper and lower gripper units 23 of the rectangular tubular body 34 are connected to different hydraulic power sources,
The operation may be controlled separately for upper and lower sides.

When the tree is securely grasped, the hydraulic device 5 of the tree felling machine 1 is operated to close the cutting blades 3 and 4, and the tree cutting is started.

The cutting edges 8 and 9 of the cutting blades 3 and 4 gradually bite while shearing the tree, and due to the wedge effect of the cutting edges 8 and 9 having the upper surface taper, the tree portion above the sheared position is gradually pushed upward. According to this,
Gripper unit slidably attached to the columnar support 2
The gripper 6 of 23 moves upward along the columnar support 2 together with the gripper unit 23 while holding the tree. Therefore, the compressive pressure does not act on the tree portion held by the cutting blades 3 and 4 and the gripper 6, and the external force that prevents the cutting edges 8 and 9 from interfering with the cutting edge does not work. Therefore, a large force is required. You can easily cut trees without doing.

Further, in this embodiment, since the single-edged cutting blades 3 and 4 having only the upper surface taper are adopted, the wedge effect is generated in the tree portion below the cutting position, and the cutting blades 3 and 4 themselves are upward. Since it does not move and no external force is applied to the tree felling machine 1, unnecessary internal stress is prevented from occurring in the tree felling machine 1, the boom shaft 43 and the like.

EFFECTS OF THE INVENTION According to the present invention, since the tree felling machine mounted on the boom is always maintained in the vertical direction in the left-right direction of the boom axis, the boom may cross the form line of the sloped terrain. Also, it is possible to smoothly position the tree felling machine with respect to the tree grown along the direction of the action line of gravity, and at the time of cutting the tree, as the cutting edge of the cutting blade cuts into the tree, In order to prevent the gripper holding the tree from moving upward together with the tree and generating compressive stress in the tree portion held by the cutting blade and the gripper, it is possible to prevent the cutting edge from having a biting force. Without, you can easily cut trees without the need for mighty force.

That is, according to both aspects of the present invention, it is possible to smoothly and easily perform the tree cutting operation.

[Brief description of drawings]

FIG. 1 is a side view showing a tree felling machine in one embodiment of the present invention, and FIG. 2 is a cutting line AB of the tree felling machine in the same embodiment.
FIG. 3 is a cross-sectional view seen from below along the line C-D, FIG. 3 is a rear view showing the tree felling machine of the same embodiment, and FIG. 4 is a plan view showing a guide piece of the tree felling machine of the same embodiment. FIG. 6 is a plan view showing the gripper unit of the tree felling machine of the same embodiment, and FIG. 6 is a plan view showing the overlapping state of the gripper unit of the tree felling machine of the same embodiment. 1 ... Tree felling machine, 2 ... Column support, 3,4 ... Cutting plate, 5 ... Hydraulic system, 6 ... Gripper, 7 ... Boom mounting bracket, 8, 9 ... Cutting edge, 10 ...
… Blade housing, 11,12 …… Shaft, 13 …… Concave notch, 14 …… Piston rod, 15 …… Pressing piece, 16,17 ……
Link member, 18 ... Cylinder, 19,20 ... Boss, 21,22 ...
… Supporting member, 23 …… Gripper unit, 24 …… Base, 25
...... Mating hole, 26 ...... Gripper pivot hole, 27 …… Cylinder pivot hole, 28 …… Hydraulic device, 29 …… Cylinder, 30,31 ……
Shaft, 32 …… Piston rod, 33 …… Shaft, 34 …… Rectangular tubular body, 35,36 …… Brim part, 37 …… Turning plate, 38 …… Brim part, 39…
… Rotation pin, 40 …… Retaining member, 41,42 …… Boom mounting hole, 43 …… Boom shaft, 44 …… Piston rod, 45 …… Guide piece, 46 …… Fitting hole, 47 …… Concave shape Notch part, 48 …… Prevention pin, 49 …… Mating hole.

Claims (2)

[Claims] 1. A pair of cutting blades having a cutting edge with an upper surface taper on one side of the lower end of a columnar support and opened and closed by hydraulic pressure, and a gripper for gripping a tree trunk is supported on the cutting blade mounting side of the support. A tree felling machine characterized by being slidably mounted along the longitudinal direction of the body. 2. The tree felling machine according to claim 1, wherein a boom mounting bracket is rotatably mounted on a side which is above a center of gravity in the longitudinal direction of the columnar support and which is opposite to a cutting blade mounting side. .