JP7169682B2 - branch cutting device - Google Patents

Description

The present invention relates to a branch cutting device.

For the purpose of improving the efficiency and ensuring safety of pruning work on standing trees, a device that moves up and down the tree trunk is equipped with a power cutting tool such as a chain saw or a circular saw that cuts the branches. Many automatic pruning machines have been devised.

Japanese Patent Application Laid-Open No. 2002-153148

When performing pruning operations with automatic pruning machines, the problem often arises that the blades get caught in the branches and render the device inoperable. If this happens, not only will the work be interrupted, but it will also be necessary for a person to climb the tree to release the jam, resulting in a significant reduction in work efficiency.

Blade bite occurs when the pruner advances beyond the speed at which the blade can advance the branch. A method has been devised to detect the overload of the chainsaw and control the advancing speed of the pruner, but since jamming occurs instantaneously under high load, it is difficult to prevent jamming because the control is not in time.

The branch cutting apparatus of the present invention includes a traveling body that revolves around the outer periphery of a tree trunk, a blade that is supported by the traveling body via an elastic member that extends and retracts in the traveling direction of the traveling body, and a displacement of the elastic member. and a sensor for measuring the traveling speed of the running body according to the measured value of the sensor.

That is, the traveling body is advanced to bring the blade into contact with the branch, the reaction force received by the blade is relieved by the elastic member, and the traveling speed of the traveling body is controlled according to the displacement of the elastic member. . By setting the elastic member so that its restoring force is equal to or less than the allowable cutting load of the blade, the travel speed of the traveling body can be limited to the speed at which the blade can cut branches or less.

In addition, the blade body can advance and retreat in the radial direction of the trunk, and the blade body has a lower end as a fulcrum and is variable in inclination with respect to the axial direction of the tree trunk. an elastic member that presses the blade against the trunk in the radial direction of the trunk; and an elastic member that presses the blade in a direction that reduces the inclination angle.

Further, in the branch cutting apparatus of the present invention, the blade body has a vertically movable structure and a tip guard at the upper end for preventing contact with the branch. It is characterized by avoiding the branch by driving an actuator for moving up and down.

Further, the branch cutting apparatus of the present invention is characterized in that it comprises a rail surrounding the periphery of the tree trunk, the traveling body circulates on the rail, and the rail is mounted on an elevator that moves up and down the tree trunk.

Alternatively, in the branch cutting apparatus of the present invention, instead of having the rail, the traveling body is an elevator that ascends and descends while revolving the tree trunk.

[First embodiment]
A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a branch cutting device. A chain saw 10 for cutting branches is fixed to a mount 12 so as to stand upright along the tree trunk. The mount 12 is attached to the main frame 11 , and the sub-frame 21 supporting the main frame 11 is fixed on the traveling body 41 via the connecting block 31 .

The running body 41 is provided with a running motor 42 and can turn on the rail 40 by rotating a roller 43 pressed against the outer edge of the annular rail 40 . A rail 40 is attached so as to surround the tree trunk. The rail 40 can be attached to and detached from the tree trunk by an opening and closing mechanism with a rotating shaft 44 as a fulcrum.

The device can be used as an automatic pruner by installing it on an elevator that raises and lowers the tree trunk. An example is shown in FIG. While driving the chain saw 10, the lifting of the elevator 50 and the turning of the traveling body 41 are combined, and the branch can be cut forward while turning the circumference of the tree trunk 100. - 特許庁

FIG. 3 shows a front view of the branch cutting device. The main frame 11 is movable around a rotating shaft 23 at a constant angle. A tension spring 22 is connected between the main frame 11 and the subframe 21 , and a sensor 20 that measures the displacement of the tension spring 22 is attached to the main frame 11 .

If the curved portion at the tip of the chain saw 10 comes into contact with a branch, there are problems such as kickback and unstable quality of the cut surface of the branch, and it is desirable to avoid cutting at this portion. A tip guard 36 mounted over the blade prevents the bend from contacting the branch.

The mount 12 is supported from both sides by a slider 14, and the slider 14 is vertically movable along a shaft 15 and supported by a compression spring 18 from below. A servomotor 24 is connected to the bottom of the mount 12 via a wire 25 .

FIG. 4 shows the AA section of FIG. The sub-frame 21 is attached to a connecting block 31 so as to be able to advance and retreat in the radial direction of the tree trunk, and a compression spring 32 presses a sprocket cover 37 against the tree trunk. As a result, the chain saw 10 keeps a constant distance without coming into contact with the surface of the tree trunk while approaching it. A servomotor 34 is connected to the subframe 21 via a wire 35 .

The mount 12 is movable at a certain angle around a rotary shaft 17, and the tip guard 16 is pressed against the tree trunk by the action of a compression spring 16. - 特許庁This structure allows the angle of the chain saw 10 to follow the bending of the tree trunk.

The apparatus has a control circuit 70 (mounting position is not shown), and FIG. 5 shows a control block diagram. The control circuit 70 drives the chainsaw motor 13, the servomotor 24, the servomotor 34, and the travel motor 42, and the driving is controlled based on the output signals of each motor and the sensor 20. FIG.

During pruning, the chain saw motor 13 and the traveling motor 42 are controlled to drive the traveling body 41 while driving the chain saw 10 . When the chain saw 10 contacts a branch, the reaction force pushes the main frame 11 and pulls the tension spring 22 . The sensor 20 measures the displacement, and changes the advancing speed of the traveling body 41 according to the value as shown in FIG. As the displacement increases, the advancing speed eventually becomes 0, but if the branch is cut forward by the restoring force of the tension spring 22, the displacement decreases and the traveling body 41 starts advancing again. That is, by setting the restoring force of the tension spring 22 within the range of the allowable cutting load of the chain saw 10, the traveling speed of the traveling body 41 is limited to the cuttable speed or less.

When the traveling speed of 0 continues for a certain period of time or more, the control circuit 70 judges that the device cannot proceed any further, and causes the traveling body 41 to move backward and the chainsaw 10 to retreat from the branch.

If the branch touches the tip guard 36 during the pruning operation and cannot be cut, the control circuit 70 detects this, lowers the chainsaw 10 to avoid the branch, and cuts the branch in the next cycle.

That is, when the branch contacts the tip guard 36, the tension spring 22 is deformed and the measured value of the sensor 20 fluctuates. Since the measured value fluctuates even when the branch is cut, the control circuit 70 first determines whether or not the branch is being cut at that time. The current (rotational load) flowing through the chain saw motor 13 is read, and if the value is the same as when the branch is not cut, it means that the branch is not being cut, and the control circuit 70 determines that the tip guard 36 is in contact with the branch. Then, the servo motor 24 is driven to pull the mount 12 downward to avoid the branch. When the tip guard 36 reaches a height where it can pass through the branch, the tension spring 22 is restored, the measurement value of the sensor 20 is restored, the servo motor 24 is returned to the original angle, and branch avoidance is completed.

By combining the above mechanisms and controls, the apparatus can automatically proceed with the work without stopping the operation in the middle.

In the pruning work, it is desirable to stop the chainsaw 10 and increase the up/down speed in order to shorten the work time and reduce the energy consumption in the areas where there are no branches of the standing tree or after the end of pruning. At this time, in order to avoid troubles such as the chain saw 10 being caught on the bark, the sub-frame 21 can be pulled by driving the servo motor 34 to keep the chain saw 10 away from the tree trunk.

[Second embodiment]
If the elevator to which the branch cutting apparatus of the present invention is attached has a mechanism that moves up and down while turning the trunk of the tree together with the main body, and if the lifting speed can be controlled, the connection block 31 in the first embodiment can be fixed directly to the elevator. , available as an automatic pruner. An example is shown in FIG.

FIG. 8 shows a control block diagram of the branch cutting device in the second embodiment. This is obtained by replacing the traveling motor 42 of the control block diagram (FIG. 5) in the first embodiment with a wheel motor 61. As shown in FIG. That is, in the present embodiment, by replacing the control of the travel motor 42 in the first embodiment with the control of the wheel motors 61, the same effect as in the first embodiment can be obtained.

[Third embodiment]
A third embodiment of the present invention will be described below with reference to the drawings. FIG. 9 is a perspective view showing a branch cutting device. A chainsaw 210 for cutting branches is fixed to a mount 212 so as to stand upright along the tree trunk. Mount 212 is attached to frame 211 , and pedestal 221 supporting frame 211 is fixed on running body 241 via linear block 231 .

The traveling body 241 is provided with a traveling motor 242 and can turn on the rail 240 by rotating a roller 243 pressed against the outer edge of the annular rail 240 . A rail 240 is attached to surround the tree trunk. The rail 240 can be attached to and detached from the tree trunk by an opening/closing mechanism with a rotating shaft 244 as a fulcrum.

The device can be used as an automatic pruner by installing it on an elevator that raises and lowers the tree trunk. An example is shown in FIG. The elevator 250 is an example of an elevator capable of directly moving up and down the tree trunk by pushing wheels against the circumference of the tree trunk. While driving the chainsaw 210 , the lifting of the elevator 250 and the turning of the traveling body 241 are combined, so that the branch can be cut spirally while turning the circumference of the tree trunk 100 . The blade for cutting branches may be a chain saw, a reciprocating saw that reciprocates the saw blade up and down, or an end mill that rotates a shaft with a blade on the side.

FIG. 11 shows a front view of the branch cutting device. The mount 212 is supported by the frame 211 via a compression spring 216 and is movable up and down by a fixed distance. Servomotor 224 is fixed to frame 211 and connected to mount 212 via belt 225 .

A frame 211 is supported on a pedestal 221 by links 214 and 215 to form a parallel crank mechanism, which is movable left and right by a predetermined distance. A tension spring 222 is connected between the link 214 and the pedestal 221, and normally leans toward the direction of travel (left). A sensor 220 is attached to the base 221 to measure the relative distance between the frame 211 and the base 221 .

If the curved portion of the tip of the chain saw 210 comes into contact with the branch, there are problems such as kickback and unstable quality of the cut surface of the branch, and it is desirable to avoid cutting at this portion. A tip guard 236 mounted over the blade prevents the bend from contacting the branch.

FIG. 12 shows a BB section of FIG. The pedestal 221 is attached to the linear block 231 so as to move forward and backward in the radial direction of the tree trunk, and a compression spring 232 presses the sprocket cover 237 against the tree trunk. As a result, the chain saw 210 keeps a constant distance without coming into contact with the surface of the tree trunk while approaching it.

The pedestal 221 is movable at a certain angle around a rotating shaft 223, and the action of a compression spring 226 presses a tip guard 236 against the tree trunk. This structure allows the angle of the chainsaw 210 to follow the bending of the tree trunk.

The device is equipped with a control circuit 270 (mounting position is not shown), a control block diagram of which is shown in FIG. Control circuit 270 drives chainsaw motor 213 , servo motor 224 , servo motor 234 , and travel motor 242 , and the driving is controlled based on the output signals of each motor and sensor 220 .

An instruction to start the pruning operation is performed by wireless communication by remote control operation by the operator. During pruning, the chain saw motor 213 and the traveling motor 242 are controlled to drive the traveling body 241 while driving the chain saw 210 . When the chain saw 210 contacts a branch, the reaction force pushes the frame 211 and pulls the tension spring 222 . The sensor 220 measures the displacement, and changes the advancing speed of the traveling body 241 as shown in FIG. 14 according to the value. As the displacement increases, the advancing speed eventually becomes 0, but if the restoring force of the tension spring 222 cuts the branches forward, the displacement decreases and the traveling body 241 starts advancing again. That is, by setting the restoring force of the tension spring 222 within the range of the allowable cutting load of the chain saw 210, the traveling speed of the traveling body 241 is limited to the cuttable speed or less. In addition to the tension spring, a rubber band may be used, or a coil spring may be attached to the joint between the link 214 and the base 221 to utilize its restoring force.

When the traveling speed of 0 continues for a certain period of time or more, the control circuit 270 judges that the device cannot proceed any further, and causes the traveling body 241 to move backward and the chainsaw 210 to move away from the branch.

If a branch touches the tip guard 236 during the pruning operation and cannot be cut, the control circuit 270 will detect this and lower the chainsaw 210 to avoid the branch and cut it on the next round.

That is, when the branch contacts the tip guard 236, the tension spring 222 is deformed and the measurement value of the sensor 220 fluctuates. Since the measured value fluctuates even when the branch is cut, the control circuit 270 first determines whether or not the branch is being cut at that time. The current (rotational load) flowing through the chain saw motor 213 is read, and if the value is the same as when the branch is not cut, it means that the branch is not being cut, and the control circuit 270 determines that the tip guard 236 is in contact with the branch. Then, the servo motor 224 is driven to pull the mount 212 downward to avoid the branches. When the tip guard 236 reaches a height where it can pass through the branch, the tension spring 222 is restored, the measured value of the sensor 220 is restored, the servo motor 224 is returned to the original angle, and branch avoidance is completed.

By combining the above mechanisms and controls, the apparatus can automatically proceed with the work without stopping the operation in the middle. The device stops the pruning operation when the operator gives a stop instruction by operating the remote controller or when the pre-input termination conditions such as the operation time and the travel distance are satisfied.

As shown in FIG. 9, a servomotor 234 fixed to the pedestal 221 is connected to the linear block 231 via a belt 235 . In the pruning work, it is desirable to stop the chainsaw 210 and increase the up/down speed in order to shorten the work time and reduce the energy consumption in areas where there are no branches of the standing tree or after the end of pruning. At this time, in order to avoid troubles such as the chain saw 210 being caught on the bark, the servo motor 234 is driven to pull the pedestal 221 toward the linear block 231, and the chain saw 210 can be separated from the tree trunk and evacuated.

When the chainsaw 210 is retracted from the tree trunk, the chainsaw 210 is tilted toward the tree trunk by the action of the compression spring 226 . Need to move distance. As a result, it is necessary to provide a space for securing a wide movable range and increase the strength of the linear block 231 that supports the device.

In order to avoid such a disadvantage, the device is equipped with a mechanism that allows the chainsaw 210 to stand upright when it is separated from the trunk. FIG. 15a shows the state around the pedestal 221 when tilted, at the BB section position of FIG. A spring pedestal 227 supporting the compression spring 226 has a relative angle with the pedestal 221 limited to a certain range. The spring pedestal 227 has casters 228 and moves on the traveling body 241 following the movement of the pedestal 221 .

The path of the caster 228 on the traveling body 241 is sloped, and the height at the retracted position is low. That is, by equalizing the inclination of the pedestal 221 due to the height difference of the slope and the maximum angle of the pedestal 221 with respect to the spring pedestal 221, the chainsaw 210 stands upright when retracted. This is shown in FIG. 15b.

[Fourth embodiment]
If the elevator to which the branch cutting device of the present invention is attached is a mechanism that ascends and descends while turning the trunk, and the ascending and descending speed can be controlled, the linear block 231 in the third embodiment is directly fixed to the elevator and automatically Can be used as a pruner. An example is shown in FIG.

The elevator 260 is composed of a main frame 261 , subframes 262 , wheels 263 and tension springs 265 . The main frame 261 and the sub-frame 262 are connected at one end so as to be swingable, and have a structure that can be opened and closed so as to surround the tree trunk. Each wheel 263 is fixed to the main frame 261 and sub-frame 262 at a certain angle with respect to the trunk axis direction. By surrounding the tree trunk with the main frame 261 and the sub-frame 262 and connecting the ends with tension springs 265, each wheel 263 is applied with contact pressure to the tree trunk, and the elevator 260 can be attached to the tree trunk in a tightening manner. . By driving the wheel motor 264 provided on the wheel 263, the elevator 260 spirally ascends and descends the tree trunk.

FIG. 17 shows a control block diagram of the branch cutting device in the fourth embodiment. This is obtained by replacing the traveling motor 242 of the control block diagram (FIG. 13) in the third embodiment with a wheel motor 264. FIG. In this embodiment, the control of the travel motor 242 in the third embodiment is replaced with the control of the wheel motors 264, and the same control as in the third embodiment is performed. The device can then proceed with the pruning operation as in the third embodiment.

1 is a perspective view showing a branch cutting device in a first embodiment according to the present invention; FIG. 1 is a perspective view showing an automatic pruning machine in which the branch cutting device in the first embodiment is attached to an elevator; FIG. It is a front view of the branch cutting device in the first embodiment. FIG. 3 is a cross-sectional view taken along the line AA of FIG. 3; It is a control block diagram of the branch cutting device in the first embodiment. FIG. 4 is a relational diagram between traveling body traveling speed and tension spring displacement in the first embodiment. It is a perspective view which shows the automatic pruner in a 2nd Example. It is a control block diagram of the branch cutting device in the second embodiment. FIG. 11 is a perspective view showing a branch cutting device according to a third embodiment of the present invention; It is a perspective view which shows the automatic pruning machine which attached the branch cutting device in 3rd Example to the elevator. It is a front view of the branch cutting device in the 3rd embodiment. FIG. 11 is a cross-sectional view taken along the line BB of FIG. 11; It is a control block diagram of the branch cutting device in the 3rd embodiment. FIG. 11 is a relational diagram between traveling body traveling speed and tension spring displacement in the third embodiment. It is explanatory drawing of the mechanism which stands upright at the time of tree trunk separation of the branch cutting device in 3rd Example. Fig. 15a shows the tilted state and Fig. 15b the upright state. It is a perspective view which shows the automatic pruner in a 4th Example. It is a control block diagram of the branch cutting device in the 4th embodiment.

10 Chainsaw 11 Main frame 12 Mount 13 Chainsaw motor 14 Slider 15 Shaft 16 Compression spring 17 Rotating shaft 18 Compression spring 20 Sensor 21 Sub-frame 22 Tension spring 23 Rotating shaft 24 Servo motor 25 Wire 31 Connection block 32 Compression spring 33 Shaft 34 Servo motor 35 Wire 36 Tip guard 37 Sprocket cover 38 Shaft holder 40 Rail 41 Running body 42 Traveling motor 43 Roller 44 Rotating shaft 45 Lock pin 50 Elevator 60 Elevator 61 Wheel motor 70 Control circuit 100 Tree trunk 101 Branch 210 Chainsaw 211 Frame 212 Mount 213 Chainsaw motor 214 link 215 link 216 compression spring 217 shaft 220 sensor 221 base 222 tension spring 223 rotating shaft 224 servo motor 225 belt 226 compression spring 227 spring base 228 caster 231 linear block 232 compression spring 233 shaft 234 servo motor 235 belt 236 chip guard 237 sprocket Cover 238 End block 240 Rail 241 Running body 242 Travel motor 243 Roller 244 Rotating shaft 245 Lock pin 250 Elevator 260 Elevator 261 Main frame 262 Sub-frame 263 Wheel 264 Wheel motor 265 Tension spring 270 Control circuit

Claims (4)

A running body that revolves around the outer periphery of the tree trunk, a blade that is supported by the running body via an elastic material that extends and retracts in the traveling direction of the running body, and a sensor that measures the displacement of the elastic material, A branch cutting device that controls the traveling speed of the running body according to the measured value of the sensor ,
The blade body can move forward and backward in the radial direction of the trunk, has a structure in which the angle of inclination with respect to the axial direction of the trunk is variable with the lower end as a fulcrum, and has covers at the upper and lower ends to prevent contact with the trunk or branches, A branch cutting device , comprising: an elastic member for pressing a blade against the trunk in the radial direction of the tree trunk; and an elastic member for pressing the blade in a direction to reduce the inclination angle . A running body that revolves around the outer periphery of the tree trunk, a blade that is supported by the running body via an elastic material that extends and retracts in the traveling direction of the running body, and a sensor that measures the displacement of the elastic material, A branch cutting device that controls the traveling speed of the running body according to the measured value of the sensor,
The blade body has a vertically movable structure and a tip guard at the upper end for preventing contact with a branch. A branch cutting device characterized by avoiding 3. The branch cutting apparatus according to claim 1 , further comprising a rail surrounding the circumference of the tree trunk, the traveling body circling on the rail, and the rail being mounted on an elevator for ascending and descending the tree trunk. Device. 3. The branch cutting apparatus according to claim 1 , wherein said traveling body is an elevator that ascends and descends while turning a tree trunk.

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