JPH0331159Y2 - - Google Patents

Description

[Detailed description of the invention] This invention refers to the tip of a chain saw that is fitted and guided by a chain saw bar installed in a pruning machine (referring to a chain saw that is fitted and guided by a curved part of the tip of a chain saw that has a substantially constant curvature). The present invention also relates to a chain saw cover branch jamming prevention device for a branch cutting machine, which has both the function of covering the non-cutting side and the function of avoiding branch cutting by the tip of the chain saw.

Conventionally, a chain saw is equipped with an appropriate number of drive wheels and idle wheels that abut and hold the periphery of a tree trunk, and that drives the drive wheels to raise the tree relative to the trunk while standing upright. There is a branch cutting machine that cuts a branch that is on its way up while rotating a chain saw that is fitted and guided by a bar around the trunk. As the speed increases, various problems such as engine stalling occur due to overload due to branch jamming, etc. Therefore, the present inventors first developed a branch jamming preventive circuit at the chain saw tip that can avoid branch cutting at the chain saw tip. A moving cam was attached to the upper part of the outer surface of the chain saw, thereby allowing the tip of the chain saw to pass under the branch without coming into contact with it.

In addition, in this type of pruning machine, the upper part of the chain saw protrudes from the machine frame along with the chain saw bar, so
When transporting this machine or attaching and removing the machine to the base of a tree trunk, it was dangerous and could injure the operator, so do not use the chain saw when doing anything other than pruning. It was covered with a bag-like cover for safety.

However, when starting the prime mover for operating the chain saw or during pruning work, the bag-shaped cover must be removed from the chain saw each time, and it is dangerous to perform the work during this time. Since it is a body, there were problems such as an increase in the number of parts and a corresponding increase in cost.

Therefore, the present invention aims to provide a cover branch jamming prevention device for a chain saw of a pruning machine, which always has the functions of both the rotary cam and the bag-shaped cover described above, and which integrates both functions. .

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

First, to explain the general structure of the pruning machine implementing the present invention, as shown in Figs. 1 to 3, the prime mover 2,
A main frame 1 with a transmission case 5 attached with a chain bar 3, drive wheels 4, etc., and an idler wheel 7
When the winding frame 6 and the winding frame 6 equipped with the winding frame 6 and the like are attached to each other with springs 8, and when the machine is elastically biased and attached to the tree trunk 9, these wheels 4 and 7 are attached to the tree trunk 9. The periphery is brought into contact with and held at a predetermined upward lead angle α.

The chain bar 3, which is mounted on the case 5 in an upwardly erect manner, has a plate material formed into an approximately elliptical shape when viewed from the front, with a partially cut-out circular portion 3a formed at the lower end of the plate material. A fitting guide groove 3 for fitting and guiding a part of the chain saw 10 in the middle part of the plate thickness on the circumferential side
b (see Fig. 5), and a chain saw drive sprocket 11 attached to the output shaft 11a protruding from the case 5 is disposed at the position of the missing circular portion 3a, and an endless A chain saw 10 is wound and hung between a chain saw bar 3 and this sprocket 11. The lower part of the chain saw bar 3 is appropriately attached to the case 5 using a vertically movable fixing adjustment means 12, and by moving and fixing the lower part, the chain saw can be attached and removed and the tension can be adjusted.

On the other hand, the power of the prime mover 2 is suitably reduced in speed within the case 5, and then transmitted in forward and reverse directions to the drive wheels 4, which enables the machine to ascend and descend spirally relative to the trunk 9. After being appropriately decelerated in the case 5, the speed is also transmitted to the sprocket 11, which operates the chain saw 10, which cuts the branch on its way up.

By the way, in the chain saw cover/branch bite prevention device 13 according to the present invention, the chain saw cover/branch bite prevention body 14, which is formed by integrally forming the cover/guide portion 15 and the cover portion 16, is attached to the outer surface side of the chain saw bar 3 (main body). (opposite side to 9) is attached to the appropriate place.

That is, the cover-cum-branch-bite prevention body 14 is
Chain saw 10 from the outer periphery of the tip of chain saw 10
This cover has a branch sliding contact surface 15a that contacts and slides against the lower peripheral surface of the branch 9a that meets the tip of the chain saw. A guide portion 15 is formed, and a cover portion 16 is continuously formed integrally with the guide portion 15 and covers the outer surface of the chain saw 10 from the outer peripheral edge on the non-cutting side of the chain saw on the side opposite to the trunk side of the chain saw 10. Place the hanging part of the cover on the outside of the chain saw at a suitable position on the outside of the chain saw bar 3, preferably at a midway part on the non-cutting side of the chain saw so that the branch being cut does not interfere when cutting the branch at the midway point on the substantially linear cutting side of the chain saw. The mounting shaft 17 can be freely rotated to
It is centrally located. Then, a stopper 18 is also erected on the chain saw bar 3 to restrict the rotation of the chain saw/branch jam prevention body 14 to an upright position that can properly cover the tip of the chain saw and the non-cutting side so as not to interfere with it. It is configured such that it is constantly biased by a spring 19 to this upright position and can be tilted in the non-cutting direction of the chain saw (counterclockwise in FIG. 4) against the force of the spring 19. Note that the cross-sectional shape of the branch sliding contact surface 15a of the cover guide portion 15 is formed into a curved shape without corners to prevent biting into the bark (see FIG. 5), and
The front end of the cover guide part 15 is formed with an appropriate branch fall-off prevention part 15b, such as a bulge shape as shown in the embodiment to prevent the branch 9a from falling off, or a roller or concave shape (not shown). . This results in
This branch fall-off prevention part 15b is located near a branch point P from the cutting side of the chain saw tip to the substantially linear cutting side of the chain saw when the cover/branch bite prevention body 14 is in the upright position, and the branch fall-off prevention part 15b Prevention part 15
b Branches that are slightly above the center and those that are slightly below are sorted out by this. Therefore, the branches that come slightly below the center of the branch fall-off prevention part 15b are pushed aside and cut near the branching point P of the chain saw. At this time, the load applied to the chain saw is greater than the normal time when cutting is performed on the substantially straight cutting side of the chain saw, so the slack on the non-cutting side of the chain saw also increases. At this time, the cover/branch jam prevention body 14 is tilted toward the non-cutting side of the chain saw, and the distance between the non-cutting side of the chain saw and the lowermost end 16a of the side cover 16 of the cover section 16 is increased to prevent interference. , is designed so that the center of inclination of the cover/branch prevention body 14 is located at a position below the lowermost end 16a.

In the figure, reference numeral 20 indicates a spring locking pin provided upright on the cover/branch jam prevention body 14 for locking one end of the spring 19, reference numeral 21 indicates a washer for preventing the spring 19 from coming off, and reference numeral 22 indicates a connection between the chain saw 10 and the trunk 9. The abutment 23 is a forward/reverse switching device that switches the driving wheel 4 to the reverse direction when the abutment 23 has risen a predetermined distance to ensure a suitable distance from the surface.

Therefore, during pruning work in which the machine is spirally raised in the direction of arrow A in FIGS. The branch 9a that is above the branch falling-off prevention part 15b first comes into contact with the cover guide part 15 of the cover-cum-branch-bite prevention body 14 in the upright position. Then, the cover guide part 15 slides and guides along the lower peripheral surface of the branch, and at the same time tilts the cover/branch jam prevention body 14 around the mounting shaft 17 in the direction of the non-cutting side of the chain saw against the force of the spring 19. However, the tip of the chain saw passes through the lower part of the branch in the direction A without coming into contact with the branch, and cutting of the branch at the tip of the chain saw is avoided (see FIG. 4). In this case, even if the branch reaches the branch fall-off prevention part 15b during sliding contact guidance, the cover/branch-bite prevention body 14 tilts while being held in a slip state without causing the branch to fall off. become. Moreover, even if the branch is caught by the branch fall-off prevention part 15b from the beginning, cutting of the branch at the tip of the chain saw is similarly avoided.
Then, the cover/branch jam prevention body 14, which has become unloaded again, self-returns to the upright position by the force of the spring 19 and is prepared for the next time, and at the same time, the machine again spirally ascends at the predetermined ascending lead angle α. Branch cutting will continue. Note that the same plate that was in contact with the cover/branch jam prevention body 14 was preferably cut at the midway point on the approximately linear cutting side of the chain saw 10 when the machine newly spirally ascended by one pitch. Ru.

If the chain saw 10 and its mounting part are configured to be elastically biased upward, it is possible to simply push down the chain saw and its mounting part without pushing down the entire machine through the cover/branch jam prevention body 14. This will allow you to pass under the branches.

As is clear from the above description, according to the present invention, the number of parts can be reduced because the chain bar 3 is provided with the cover branch jamming prevention body 14 that has both the functions of a conventional rotary cam and a bag-like cover. Also,
The cover-cum-branch-bite prevention body 14 is normally in an upright position that properly covers the distal end of the chain saw 10 and the non-cutting side, so it is not suitable for conventional chain saws in which the bag-like cover is removed each time. Safety can be ensured even when starting the operating prime mover 2 or during pruning work, and there is no need to attach or remove the bag-like cover as in the past, which eliminates the inconvenience. In addition, since the cover/branch bite prevention body 14 covers the outer surface of the chain saw 10 on the side opposite to the trunk side from the distal end of the chain saw and the outer periphery on the non-cutting side, the strength structure of the branch cutting part is Since it becomes a member and is advantageous in terms of strength, the branch cutting part member can be made lightweight.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a branch cutting machine embodying the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a sectional view of the main part thereof, and Fig. 4 is a chain saw cover branch jamming prevention device according to the present invention. FIG. 5 is an enlarged front view showing the same, and FIG. 5 is a sectional view thereof. Code, 3... Chain bar, 4, 7... Wheels (4... Driving wheels, 7... Idling wheels), 9... Stem,
9a... branch, 10... chain saw, 14... cover/branch bite prevention body, 15... cover guide section, 16
...Cover part.

Claims (1)

[Claims for Utility Model Registration] 1. An appropriate number of wheels 4 and 7 are mounted around a tree trunk 9 and are capable of rising relative to said trunk 9 by driving one or more wheels 4. The branch cutting machine is equipped with a chain saw bar 3 in an upwardly erect state on which a chain saw 10 is fitted and guided to cut a branch 9a on the way up while being rotated relative to the trunk 9. 10
A cover guide part 15 that covers the tip and slides in contact with and guides the lower circumferential surface of the branch 9a that meets the tip, and a cover part 16 that covers the non-cutting side of the chain saw 10 are integrally formed. A cover/branch bite prevention body 14 is pivotally attached to an appropriate position on the outer surface of the chain saw bar 3 so as to be tiltable toward the non-cutting side of the chain saw 10, and the cover/branch bite prevention body 14 is attached to the tip of the chain saw 10 and the chain saw 10. A cover branch jamming prevention device for a chain saw of a branch cutting machine, characterized in that the cover is permanently biased in an upright position to properly cover the non-cutting side so as not to interfere with it. 2. Remove the tip of the chain saw 10 and the non-cutting side cover by the cover/branch jam prevention body 14 from the outer periphery of the chain saw 10.
A cover for a chain saw of a branch cutting machine according to claim 1, characterized in that the device is formed to extend over the outer surface of the tree on the side opposite to the trunk side.