JP7755510B2 - Work machinery - Google Patents

Description

This disclosure relates to a work machine equipped with a timber processing device that is used, for example, in forestry work sites and performs the work of cutting logs from trees (timber processing).

A typical example of construction machinery, a hydraulic excavator, is generally equipped with a self-propelled lower chassis and an upper rotating chassis mounted on the lower chassis so that it can rotate. A front device for work is provided at the front of the upper rotating chassis, and various tasks can be performed by changing the attachments attached to the tip of the front device. Hydraulic excavators are equipped with a hydraulic pump driven by a prime mover such as an engine, and the hydraulic actuators installed on the hydraulic excavator are operated by pressurized oil discharged from the hydraulic pump.

When a hydraulic excavator is used in forestry work, a logging device such as a harvester or processor is attached to the front equipment. Logging devices called harvesters generally perform logging tasks such as felling trees (standing trees) and delimbing and cutting (bucking) the felled trees, while logging devices called processors perform logging tasks such as delimbing and cutting the felled trees. For this reason, logging devices are usually equipped with hydraulic chainsaws, which are powered by pressurized oil from a hydraulic pump and perform tasks such as felling and cutting the trees.

The hydraulic pump installed in a hydraulic excavator adjusts the operating speed of the hydraulic actuator by increasing or decreasing the discharge flow rate in accordance with the engine speed and the amount of operation of the control lever. The hydraulic pump also prevents the engine's output from becoming excessive by increasing or decreasing the discharge flow rate in accordance with the load on the hydraulic actuator.

If the chainsaw's rotation speed is insufficient when cutting trees, the cut surface is likely to become rough and the wood is likely to crack during cutting, resulting in a problem of lower quality logs being shipped as products. In particular, if the tree has a large outer diameter (thickness) or is very hard (hard) depending on the type of tree, the chainsaw's rotation speed will decrease, making the cut surface rough and the wood is likely to crack during cutting.

In response to this, a lumber processing device has been proposed that increases the engine speed and hydraulic pump discharge flow rate when cutting trees with a chainsaw. With this lumber processing device, increasing the chainsaw speed when cutting trees prevents the logs from roughening the cut surface and cracking during cutting, thereby maintaining the high quality of the logs that are shipped (see Patent Document 1).

JP 2015-62355 A

However, in forestry work where timber processing is carried out, the hardness of different types of trees varies, and hard and soft trees are mixed together. For this reason, for example, when cutting soft trees that are less likely to cause roughness on the cut surface of the log, there is no need to increase the engine speed. Furthermore, there is no need to increase the engine speed when cutting trees that require lower quality, such as thinned trees or the tips of tapered trees.

As such, with conventional technology, the engine speed increases when cutting low-quality logs using a chainsaw, even when cutting low-hardness (soft) trees, trees with small outer diameters, or trees that have been thinned out, resulting in a large amount of fuel being wasted with conventional lumber processing equipment, which not only increases the cost of producing logs but also has a negative impact on the environment.

The object of the present invention is to provide a work machine that can control the rotation speed of the motor according to the outer diameter of the tree when cutting the tree using a cutting machine.

The present invention is a work machine comprising a self-propelled vehicle body equipped with a prime mover that drives a hydraulic pump, a front device provided on the vehicle body, and a log processing device provided on the front device for processing trees, wherein the log processing device is a work machine having a cutter driven by pressurized oil discharged from the hydraulic pump and cutting the trees, the log processing device comprising a feeder that grips the trees and feeds them toward the cutter, an outer diameter detector that detects the outer diameter of the trees, and a controller that controls the rotation speed of the prime mover in accordance with the outer diameter of the trees detected by the outer diameter detector, wherein when cutting the trees with the cutter, the controller increases the rotation speed of the prime mover from a standard rotation speed as the outer diameter of the trees detected by the outer diameter detector increases, and when feeding the trees with the feeder, the controller returns the rotation speed of the prime mover to the standard rotation speed .

According to the present invention, when cutting trees using the cutting machine of a timber processing machine, the controller controls the rotation speed of the motor according to the outer diameter of the tree detected by the outer diameter detector. As a result, the rotation speed of the motor increases and the rotation speed of the cutting machine increases only when cutting trees with a large outer diameter (thick trees). This allows thick trees to be cut smoothly, and prevents the rotation speed of the cutting machine from becoming excessive when cutting trees with a small outer diameter (thin trees).

1 is a left side view showing a hydraulic excavator equipped with a material processing device according to a first embodiment of the present invention. FIG. 3 is an explanatory view of the gripping device as seen from the direction of arrows III-III in FIG. 2. 4 is an explanatory view of the feed device as seen from the direction of arrows IV-IV in FIG. 2. 3 is an explanatory diagram of the cutting device as seen from the direction of arrows VV in FIG. 2. FIG. 4 is an enlarged view showing an angle sensor and the like in FIG. 3 . 7 is an enlarged view of the angle sensor and the like as viewed from the direction of arrows VII-VII in FIG. 6. FIG. 10 is an explanatory diagram showing the state in which the gripping device grips a large-diameter tree. FIG. 10 is an explanatory diagram showing a state in which the gripping device grips a small-diameter tree. FIG. 2 is a block diagram including an angle sensor, a controller, an input device, and an engine controller according to the first embodiment. FIG. 10 is an explanatory diagram showing a list of engine rotation speeds set according to the outer diameter of trees in the first embodiment. FIG. 10 is an explanatory diagram showing an increase or decrease in engine speed in response to a change in the outer diameter of a tree in the lumber processing process according to the first embodiment. FIG. 10 is a block diagram including an angle sensor, a controller, an input device, and an engine controller according to a second embodiment. FIG. 10 is an explanatory diagram showing a list of engine rotation speeds set according to the outer diameter and hardness of trees in the second embodiment. FIG. 10 is an explanatory diagram showing an increase or decrease in engine speed in response to a change in the outer diameter of a cedar tree in a lumber manufacturing process according to the second embodiment. FIG. 10 is an explanatory diagram showing an increase or decrease in engine speed in response to a change in the outer diameter of a larch tree in a lumber manufacturing process according to the second embodiment.

An embodiment of a work machine according to the present invention will be described in detail below, taking as an example an application to a hydraulic excavator, with reference to Figures 1 to 16. Note that in this embodiment, the traveling direction of the hydraulic excavator will be referred to as the fore-and-aft direction, and the direction perpendicular to the traveling direction will be referred to as the left-and-right direction.

Figures 1 to 12 show a first embodiment. The hydraulic excavator 1 shown in Figure 1 is deployed to forestry sites and performs timber processing work such as delimbing and cutting felled trees using a timber processing device 11 called a processor (described below). The hydraulic excavator 1 comprises a self-propelled crawler-type lower traveling body 2 and an upper rotating body 4 rotatably mounted on the lower traveling body 2 via a slewing device 3, and the lower traveling body 2 and upper rotating body 4 form a vehicle body. A front device 5 is provided in front of the upper rotating body 4, and a timber processing device 11 is attached to the tip of the front device 5.

The lower traveling body 2 has a track frame 2A that serves as a base, and left and right side frames 2B (only the left side is shown) that extend in the fore-and-aft direction are attached to the track frame 2A. A traveling device (drive wheel) 2C is attached to one fore-and-aft end of each of the left and right side frames 2B, and an idler wheel 2D is attached to the other fore-and-aft end of each. An endless track (crawler) 2E is wound around the traveling device 2C and the idler wheel 2D, and by rotating the track 2E using the traveling device 2C, the hydraulic excavator 1 can travel stably on slopes, uneven terrain, etc.

The front device 5 is composed of a boom 5A, an arm 5B, links 5C and 5D, an adapter 5E for attaching the material-making device 11, a boom cylinder 5F, an arm cylinder 5G, and a work tool cylinder 5H. The base end of the boom 5A is rotatably attached to the front side of the swivel frame 6 (described below), and an arm 5B is rotatably attached to the tip of the boom 5A. One end of a link 5C and an adapter 5E are rotatably attached to the tip of the arm 5B. Furthermore, one end of a link 5D is rotatably attached to the adapter 5E.

The boom cylinder 5F is located between the swivel frame 6 and the boom 5A and rotates the boom 5A up and down relative to the swivel frame 6. The arm cylinder 5G is located between the boom 5A and the arm 5B and rotates the arm 5B up and down relative to the boom 5A. The implement cylinder 5H is connected to the arm 5B and adapter 5E via links 5C and 5D. Specifically, the bottom side of the implement cylinder 5H is rotatably attached to the arm 5B, and the rod side of the implement cylinder 5H is rotatably attached to the other ends of links 5C and 5D. Therefore, the extension and retraction of the implement cylinder 5H is transmitted to the adapter 5E via links 5C and 5D, causing the adapter 5E to rotate up and down relative to the arm 5B.

The upper rotating body 4 is mounted on the lower running body 2 so that it can rotate via a rotating device 3. The upper rotating body 4 includes a rotating frame 6, a counterweight 7, an engine 8, an exterior cover 9, a cab 10, etc.

The swivel frame 6 forms the base of the upper swivel body 4 and is rotatably mounted on the lower running body 2 via the swivel device 3. The swivel frame 6 has a bottom plate (not shown) and left and right vertical plates (not shown) that are erected on the bottom plate, face each other in the left-right direction, and extend in the front-to-back direction. The base ends of the boom 5A and the boom cylinder 5F are rotatably attached to the front ends of the left and right vertical plates of the swivel frame 6. A counterweight 7 is attached to the rear ends of the left and right vertical plates of the swivel frame 6. The counterweight 7 maintains weight balance with the front device 5.

The engine 8, which serves as a prime mover, is mounted on the revolving frame 6, located in front of the counterweight 7. The engine 8 drives a hydraulic pump (not shown) which serves as a power source, and the hydraulic pump discharges pressurized oil when driven by the engine 8. The pressurized oil discharged from the hydraulic pump is supplied to various hydraulic actuators mounted on the hydraulic excavator 1 via control valves (not shown). An exterior cover 9 is located in front of the counterweight 7, and the engine 8, hydraulic pump, control valves, and other onboard equipment mounted on the revolving frame 6 are housed within the exterior cover 9.

The cab 10 is located at the front left of the revolving frame 6. The cab 10 is shaped like a box that defines the driver's compartment, and inside the cab 10 is a driver's seat (not shown) where the operator sits. A travel lever and pedal device (not shown) that controls the travel operation of the hydraulic excavator 1 is located in front of the driver's seat, and on both left and right sides of the driver's seat are operating lever devices (not shown) that control the rotational movement of the upper revolving body 4 and the operation of the front device 5. Inside the cab 10, there is also a controller 37 (described below) that controls the engine 8 RPMs, various log-making operation buttons (not shown) for operating the log-making device 11, an input device 38, and the like.

Next, the timber processing device used in this embodiment will be described with reference to Figures 2 to 9, taking as an example a timber processing device 11, commonly called a processor, which performs timber processing work such as pruning and cutting felled trees.

The log processing device 11 is attached to the adapter 5E of the front device 5 and performs log processing operations such as delimbing and cutting of felled trees W. The log processing device 11 is composed of a support member 12, a log processing frame 13, a gripping device 18, a feeding device 22, and a cutting device 30, which will be described later.

The support member 12 is attached to the tip of the adapter 5E and supports the lumber frame 13. The support member 12 has an attachment portion 12A attached to the tip of the adapter 5E so that it can rotate in the front-to-rear direction, and an arm portion 12B extending downward from the attachment portion 12A, with the lower side of the arm portion 12B branching into two parts. A rotation mechanism (not shown) including, for example, a hydraulic motor is provided between the attachment portion 12A and the arm portion 12B, and the arm portion 12B can rotate around an axis extending in the vertical direction relative to the attachment portion 12A. In addition, a frame-shaped guide 12C is fixed to the outer surface of the arm portion 12B.

The lumber-making frame 13 is attached to the arm portion 12B of the support member 12. The lumber-making frame 13 forms the base of the lumber-making device 11 and has a base 14, a gripping device mounting portion 15, a feeding device mounting portion 16, and a cutting device mounting portion 17. The middle portion of the base 14 in the longitudinal direction is attached to the lower end of the arm portion 12B that constitutes the support member 12 via a shaft 14A, and the base 14 is rotatable around the shaft 14A.

The gripping device mounting portion 15 is provided at one end of the base 14 in the longitudinal direction. The gripping device mounting portion 15 is composed of a pair of plates facing each other in the longitudinal direction of the base 14, and has a pair of protruding portions 15A, 15B that protrude in a direction perpendicular to the longitudinal direction of the base 14 (see Figure 3). A gripping device 18 and other components are attached to this pair of protruding portions 15A, 15B.

The feeder attachment section 16 is located adjacent to the gripper attachment section 15 and is located midway along the length of the base 14. The feeder attachment section 16 is composed of a pair of plates facing each other along the length of the base 14, and has a pair of protrusions 16A, 16B that protrude perpendicular to the length of the base 14 (see Figure 4). A feeder 22 is attached to this pair of protrusions 16A, 16B.

The cutting device mounting portion 17 is located adjacent to the feeder mounting portion 16 at the other longitudinal end of the base 14. The cutting device mounting portion 17 has a bracket 17A that protrudes in a direction perpendicular to the longitudinal direction of the base 14 (see Figure 5). The cutting device 30 is attached to the bracket 17A.

The gripping device 18 is attached to the gripping device mounting portion 15 of the timber frame 13 and grips felled trees W. The gripping device 18 includes a pair of tongs 19, 20 that are openably and closably attached to the gripping device mounting portion 15, and a tong cylinder 21 that opens and closes the tongs 19, 20. The tongs 19, 20 have an overall J-shaped curved shape, and a blade (not shown) for delimbing the tree W is attached to their outer surfaces. The tongs 19 are rotatably supported on one extension portion 15A of the gripping device mounting portion 15 using a tong connecting pin 19A. The tongs 20 are rotatably supported on the other extension portion 15B of the gripping device mounting portion 15 using a tong connecting pin 20A.

The tongue cylinder 21 is composed of a hydraulic cylinder and is provided between the pair of tongues 19, 20. Specifically, one end (bottom side) of the tongue cylinder 21 is connected to the base end of the tongue 20 using a cylinder connecting pin 21A, and the other end (rod side) of the tongue cylinder 21 is connected to the base end of the tongue 19 using a cylinder connecting pin 21B. As shown in Figure 7, a cylindrical shaft 21C protrudes concentrically from the tip of the cylinder connecting pin 21B, and one end 36A of the angle sensor lever 36 (described below) is engaged with the shaft 21C.

The tong cylinder 21 receives a supply of pressurized oil from a hydraulic pump when, for example, a timber processing operation button (not shown) for the gripping device 18 located inside the cab 10 is operated. This causes the opening degree of the tongs 19, 20 to change in response to the extension and retraction of the tong cylinder 21, and the tongs 19, 20 rotate around the tong connecting pins 19A, 20A, thereby grasping the tree W from the radially outer side.

The feeder 22 is attached to the feeder mounting portion 16 of the timber frame 13 and grips the felled tree W while feeding it toward the cutting device 30. As shown in FIG. 4, the feeder 22 is composed of a pair of feeder arms 23, 24, a link 25, feeder cylinders 26, 27, and feeder tracks 28, 29. One end of the feeder arm 23 is rotatably supported on the protrusion 16A of the feeder mounting portion 16 via an arm connecting pin 23A. One end of the feeder arm 24 is rotatably supported on the protrusion 16B of the feeder mounting portion 16 via an arm connecting pin 24A. A feeder track 28 is attached to the other end of the feeder arm 23, and a feeder track 29 is attached to the other end of the feeder arm 24.

Link 25 is a linearly extending rod-shaped body that connects one end of feeder arms 23, 24. Specifically, one end of feeder arm 23 is provided with protrusion 23B that protrudes in a direction away from arm connecting pin 23A, and one end of feeder arm 24 is provided with protrusion 24B that protrudes in a direction away from arm connecting pin 24A. One end of link 25 is connected to protrusion 23B of feeder arm 23 via link pin 25A, and the other end of link 25 is connected to protrusion 24B of feeder arm 24 via link pin 25B.

The feeder cylinder 26 is a hydraulic cylinder and is provided between one protrusion 16A of the feeder mounting portion 16 and the feeder arm 23. The feeder cylinder 27 is a hydraulic cylinder and is provided between the other protrusion 16B of the feeder mounting portion 16 and the feeder arm 24. Specifically, one end (bottom side) of the feeder cylinder 26 is connected to the other end of the feeder arm 23 via a cylinder connecting pin 26A, and the other end (rod side) of the feeder cylinder 26 is connected to one protrusion 16A via a cylinder connecting pin 26B. One end (bottom side) of the feeder cylinder 27 is connected to the other end of the feeder arm 24 via a cylinder connecting pin 27A, and the other end (rod side) of the feeder cylinder 27 is connected to the other protrusion 16B via a cylinder connecting pin 27B.

The feeder track 28 is attached to the other end of the feeder arm 23, and the feeder track 29 is attached to the other end of the feeder arm 24. The feeder track 28 is an endless strip extending along the base 14 of the timber frame 13, and is driven to rotate by a feeder motor 28A consisting of a hydraulic motor. The outer surface of the feeder track 28 is provided with multiple protrusions 28B that dig into the surface of the tree W. Like the feeder track 28, the feeder track 29 is also an endless strip extending along the base 14 of the timber frame 13, and is driven to rotate by a feeder motor 29A consisting of a hydraulic motor. The outer surface of the feeder track 29 is provided with multiple protrusions 29B that dig into the surface of the tree W.

The feeder cylinders 26, 27 are supplied with pressurized oil from a hydraulic pump by operating a log-making operation button (not shown) for the feeder 22 located inside the cab 10. When the feeder cylinders 26, 27 are retracted, the feeder tracks 28, 29 move away from each other via the feeder arms 23, 24. On the other hand, when the feeder cylinders 26, 27 are extended, the feeder tracks 28, 29 move closer to each other via the feeder arms 23, 24, radially clamping and gripping the tree W. Because one end of the feeder arms 23, 24 is connected via a link 25, the operation of the feeder arms 23, 24 is always synchronized. Therefore, when the feeder cylinders 26, 27 are extended and the feeder tracks 28, 29 are gripping the tree W, the tree W is positioned in the center of the log-making device 11. Then, with the feeder tracks 28, 29 gripping the tree W, pressure oil is supplied from the hydraulic pump to the feeder motors 28A, 29A. This causes the feeder tracks 28, 29 to rotate, and the tree W is sent out toward the cutting device 30.

The cutting device 30 is attached to the cutting device mounting portion 17 of the timber frame 13 and cuts the trees W fed by the feeder 22 to an appropriate length (the length of the logs to be used as products). The cutting device 30 includes a chainsaw 31 as a cutting machine swingably mounted on the bracket 17A of the cutting device mounting portion 17, a chainsaw motor 32 consisting of a hydraulic motor that drives the chainsaw 31, and a swing cylinder 33 that swings the chainsaw 31 relative to the bracket 17A. The chainsaw 31 has a saw chain that runs around the outer periphery of the guide bar 31A and is engaged with a sprocket (not shown) attached to the chainsaw motor 32. The chainsaw motor 32 is driven by operating a timber operation button for the cutting device 30 located inside the cab 10, and the torque of the chainsaw motor 32 is transmitted to the chainsaw 31 via the sprocket.

The guide bar 31A of the chainsaw 31 is swingably supported on the bracket 17A via the swing shaft 31B. A swing link 31C is provided on the guide bar 31A, protruding away from the swing shaft 31B. The swing cylinder 33 is provided between the bracket 17A and the swing link 31C. Specifically, one end (bottom side) of the swing cylinder 33 is connected to the bracket 17A via a cylinder connecting pin 33A, and the other end (rod side) of the swing cylinder 33 is connected to the swing link 31C via a cylinder connecting pin 33B. Therefore, the chainsaw 31, driven by the chainsaw motor 32, swings around the swing shaft 31B as the swing cylinder 33 extends and retracts, allowing it to cut trees W.

The tong cylinder 21, feeder cylinders 26, 27, feeder motors 28A, 29A, and chainsaw motor 32 provided on the log processing device 11 are each connected via hydraulic hoses to a control valve (not shown) mounted on the upper rotating body 4. These multiple hydraulic hoses are housed, for example, in a single flexible protective pipe 34 and extend to the log processing device 11 via the front device 5. The intermediate portion of the protective pipe 34 is held by a guide 12C provided on the support member 12.

The timber processing device 11 grasps the root W1 side of the felled tree W with the tongs 19, 20 and cuts the root W1 with the chainsaw 31. Next, while the tree W is fed in the direction of arrow A in Figure 2 by the feeder tracks 28, 29, the tree W is delimbed with blades (not shown) attached to the tongs 19, 20. The tree W is then cut into fixed length intervals (e.g., 3 m) with the chainsaw 31. In this way, by repeating the feeding by the feeder tracks 28, 29, delimbing by the tongs 19, 20, and cutting by the chainsaw 31, multiple logs are produced from a single tree W. In this way, by starting the timber processing operation from the root W1 of the tree W, the outer diameter of the tree W cut by the chainsaw 31 gradually becomes smaller (thinner).

Next, we will explain the angle sensor 35 used in this embodiment as an outer diameter detector that detects the outer diameter dimensions of the tree W to be processed.

The angle sensor 35, which serves as an outer diameter detector, is attached to the tong connecting pin 19A, which connects the gripping device mounting portion 15 of the lumber frame 13 to the tongs 19. As shown in Figures 6 and 7, the angle sensor 35 is attached to the tip of the tong connecting pin 19A and has a rotating shaft 35A that is rotatably arranged concentrically with the tong connecting pin 19A. As shown in Figure 10, the angle sensor 35 is connected to the controller 37 (described below) via a cable 35B and outputs a signal to the controller 37 corresponding to the opening degree of the tongs 19, 20. The cable 35B extends from the controller 37 via the front device 5 to the lumber manufacturing device 11, with the middle portion of the cable 35B held by a guide 12C attached to the support member 12 (see Figure 2).

The angle sensor lever 36 is located between the cylinder connecting pin 21B, which connects the tong cylinder 21 and the tongs 19, and the rotation shaft 35A of the angle sensor 35. The angle sensor lever 36 has a bent crank shape, and one end 36A of the angle sensor lever 36 is engaged with the shaft 21C of the cylinder connecting pin 21B. The other end 36B of the angle sensor lever 36 is fixed to the rotation shaft 35A of the angle sensor 35 using a fixing pin 36C.

As shown in Figures 8 and 9, when the tongs 19, 20 open and close in response to differences in the outer diameter of the tree W, the cylinder connecting pin 21B rotates around the tong connecting pin 19A, causing the angle sensor lever 36 to rotate together. The rotation of the angle sensor lever 36 is transmitted to the rotation shaft 35A of the angle sensor 35, which outputs a signal to the controller 37 via cable 35B, with electrical resistance varying between 0V and 5V in proportion to the amount of rotation of the rotation shaft 35A (opening of the tongs 19). As shown in Figure 8, when the outer diameter of the tree W is large and the opening of the tongs 19, 20 is large, a signal of, for example, 1V is output to the controller 37. However, as shown in Figure 9, when the outer diameter of the tree W is small and the opening of the tongs 19, 20 is small, the signal output to the controller 37 changes to 2V.

The controller 37 is located, for example, in the cab 10. The input side of the controller 37 is connected to the angle sensor 35, an input device 38 (described later), and the like. The output side of the controller 37 is connected to the engine controller 39 and the like. The controller 37 has an outer diameter calculation unit 37A that calculates the outer diameter of the tree W, and a rotation speed determination unit 37B that determines the rotation speed of the engine 8. The outer diameter calculation unit 37A calculates the outer diameter of the tree W based on the detection signal from the angle sensor 35 and outputs the outer diameter of the tree W to the rotation speed determination unit 37B. Multiple set rotation speeds of the engine 8 set according to the outer diameter of the tree W are input in advance from the input device 38 to the rotation speed determination unit 37B. As a result, the rotation speed determination unit 37B determines the rotation speed of the engine 8 corresponding to the outer diameter of the tree W calculated by the outer diameter calculation unit 37A, and outputs this rotation speed to the engine controller 39.

The input device 38 is attached to an operation monitor (not shown) installed in the cab 10, for example, and is operated by the operator. The input device 38 sets multiple rotation speeds for the engine 8, which drives the hydraulic pump that powers the chainsaw 31 (chainsaw motor 32), depending on the outer diameter of the tree W to be cut, and inputs these multiple set rotation speeds into the controller 37 in advance. For example, as shown in the table in FIG. 11, multiple set rotation speeds are input, which are increased or decreased from a standard rotation speed (standard rotation speed) for the engine 8 depending on changes in the outer diameter of the tree W to be cut. In this embodiment, when the outer diameter of the tree W is between 25 cm and 45 cm, the set rotation speed of the engine 8 is the standard rotation speed. When the outer diameter of the tree W is between 0 and 25 cm, the set rotation speed of the engine 8 is 100 rpm lower than the standard rotation speed. When the outer diameter of the tree W is between 45 cm and 55 cm, the set rotation speed of the engine 8 is 100 rpm higher than the standard rotation speed.

The rotation speed determination unit 37B of the controller 37 is connected to the engine controller 39, which controls the rotation speed of the engine 8. The rotation speed determination unit 37B determines whether to increase or decrease the rotation speed of the engine 8 relative to the standard rotation speed based on the outer diameter of the tree W calculated by the outer diameter calculation unit 37A and multiple set rotation speeds of the engine 8 corresponding to the outer diameter of the tree W input using the input device 38 (see Figure 11). The rotation speed of the engine 8 determined by the rotation speed determination unit 37B is then output to the engine controller 39, whereby the engine 8 is controlled by the engine controller 39, and the rotation speed of the engine 8 is increased or decreased appropriately depending on the outer diameter of the tree W.

The timber processing device 11 according to this embodiment has the configuration described above. Below, we will explain the process of using the timber processing device 11 to convert felled trees W into logs.

First, the operator gets into the cab 10 and operates the travel lever and pedal device (not shown) located in front of the driver's seat to move the hydraulic excavator 1 to the work site, and then operates the control lever devices (not shown) located on both the left and right sides of the driver's seat to move the timber processing device 11 attached to the tip of the front device 5 toward the felled tree W.

Next, the operator operates the input device 38 attached to the operation monitor (not shown) inside the cab 10. This causes the engine speed when cutting the tree W with the chainsaw 31 to be input in advance to the controller 37 as a set speed increased or decreased from the standard speed depending on the outer diameter of the tree W. As shown in FIG. 11 , in this embodiment, when the outer diameter of the tree W is in the range of 25 cm to 45 cm, the increase or decrease in engine speed is 0, and the set speed of the engine 8 is the standard speed. When the outer diameter of the tree W is in the range of 0 to 25 cm, the set speed of the engine 8 is 100 rpm lower than the standard speed. When the outer diameter of the tree W is in the range of 45 cm to 55 cm, the set speed of the engine 8 is 100 rpm higher than the standard speed.

Next, the operator operates the timber processing operation button (not shown) located inside the cab 10 to begin timber processing. As a result, as shown in FIG. 2, the timber processing device 11 extends and retracts the tong cylinder 21, causing the tongs 19, 20 to grip the root W1 side of the tree W. At this time, a signal corresponding to the opening angle of the tongs 20 is output from the angle sensor 35 to the controller 37. The outer diameter calculation unit 37A of the controller 37 calculates the outer diameter of the tree W gripped by the tongs 19, 20 based on the voltage of the signal output from the angle sensor 35, and outputs the calculated outer diameter to the rotation speed determination unit 37B.

Here, in the first step of the timber production process shown in Figure 12, if the outer diameter of the root W1 side of the tree W held by the tongs 19, 20 is in the range of 35 to 40 cm, the increase/decrease in engine speed input from the input device 38 to the speed determination unit 37B of the controller 37 will be 0. Therefore, the chainsaw 31 is driven with the engine 8 maintaining the standard speed, and the root W1 of the tree W is cut.

After cutting the root W1 of the tree W in the first step, the process moves to the second step. In the second step, the feeder cylinders 26, 27 of the feeder 22 are extended, and the feeder motors 28A, 29A are operated while the feeder tracks 28, 29 grip the tree W. This causes the feeder tracks 28, 29 to feed a certain length of the tree W toward the cutting device 30 (in the direction of arrow A in Figure 2), at which time the branches are delimbed by blades (not shown) attached to the tongs 19, 20. When the tree W is fed by the feeder 22, the engine speed does not increase or decrease, and the standard speed of the engine 8 is maintained.

After the tree W is sent out by the feed device 22 to the cutting device 30 by a certain length, the tree W is cut by the chainsaw 31. At this time, if the outer diameter of the tree W detected by the angle sensor 35 is in the range of 30 to 35 cm, the increase/decrease in engine speed input from the input device 38 to the speed determination unit 37B of the controller 37 will be 0. Therefore, the chainsaw 31 is driven with the engine 8 maintaining the standard speed, and the tree W is cut (bucked) into logs of a certain length.

After the tree W is cut in the second step, the process moves to the third step. In the third step, similar to the second step, the tree W is fed by the feed device 22 toward the cutting device 30 by a fixed length, and the branches are delimbed by the blades of the tongs 19 and 20. When the tree W is fed by the feed device 22, the engine 8 maintains its standard rotation speed. Next, the tree W is cut by the chainsaw 31. At this time, the outer diameter of the tree W detected by the angle sensor 35 is in the range of 20 to 25 cm, and the increase/decrease value of the engine rotation speed input from the input device 38 to the rotation speed determination unit 37B of the controller 37 is −100 min ⁻¹ . Therefore, the controller 37 outputs a control signal to the engine controller 39 to reduce the rotation speed of the engine 8 by 100 rpm compared to the standard rotation speed. As a result, the rotation speed of the engine 8 is automatically controlled by the engine controller 39. As a result, the chainsaw 31 is driven with the rotation speed of the engine 8 reduced by 100 rpm compared to the standard rotation speed, and the tree W is cut into logs of a fixed length.

After the tree W is cut in the third step, the process moves to the fourth step. In the fourth step, the tree W is again fed by the feeding device 22 toward the cutting device 30 by a fixed length, and the branches are delimbed by the blades of the tongs 19, 20. When the tree W is fed by the feeding device 22, the engine 8 maintains the standard rotation speed. Next, when the tree W is cut by the chainsaw 31, the outer diameter of the tree W is in the range of 5 to 10 cm, and the increase/decrease value of the engine rotation speed input from the input device 38 to the rotation speed determination unit 37B of the controller 37 is -100 min ^-1 . As a result, the chainsaw 31 is driven with the rotation speed of the engine 8 reduced by 100 rpm from the standard rotation speed, and the tree W is cut into logs of a fixed length.

In this way, the timber processing device 11 according to this embodiment can control the rotation speed of the engine 8 in accordance with the outer diameter of the tree W when using the chainsaw 31 to cut multiple logs from a single tree W. Therefore, when the outer diameter of the tree W to be cut is large, the rotation speed of the engine 8 can be increased above the standard rotation speed, and when the outer diameter of the tree W to be cut is small, the rotation speed of the engine 8 can be decreased below the standard rotation speed. This makes it possible to automatically reduce the rotation speed of the engine 8 when cutting a portion of a single tree W with a small outer diameter or when cutting logs with a lower required quality, such as the tip of the tree W.

As a result, when cutting trees W using the chainsaw 31, the operator is no longer required to perform the tedious task of increasing or decreasing the engine 8 rotation speed depending on the outer diameter of the tree W, improving workability during cutting. Furthermore, because the timber processing device 11 can control the engine 8 rotation speed depending on the outer diameter of the tree W to be cut, when cutting multiple logs from a single tree W, the chainsaw 31 can always be driven at an appropriate engine rotation speed depending on changes in the outer diameter of the tree W. As a result, the quality of the cut logs can be maintained at a good level, and by reducing the amount of fuel supplied to the engine 8, log production costs can be reduced and the forestry site environment can be maintained in a good condition.

Next, Figures 13 to 16 show a second embodiment of the present invention. A feature of this embodiment is that the controller increases or decreases the engine speed based on the outer diameter of the tree detected by the diameter detector and multiple engine speed settings input from an input device that take into account the outer diameter and the hardness of the tree. In this embodiment, the same components as in the first embodiment are designated by the same reference numerals, and their description will be omitted.

In Figure 13, the input device 41 used in this embodiment is connected to the input side of the controller 37, similar to the input device 38 in the first embodiment. The input device 41 is operated by the operator to set multiple rotation speeds for the engine 8, which drives the hydraulic pump that serves as the power source for the chainsaw 31, taking into account the outer diameter of the tree W to be cut and the hardness of the tree W, and inputs these multiple set rotation speeds into the controller 37 in advance. The controller 37 increases or decreases the rotation speed of the engine 8 based on the outer diameter of the tree W detected by the angle sensor 35 and the multiple set rotation speeds input from the input device 41 taking into account the outer diameter of the tree W and the hardness of the tree W.

For example, as shown in the table in Figure 14, multiple set rotation speeds are input, each of which is increased or decreased from the standard rotation speed (standard rotation speed) for the engine 8 in accordance with the changes in the outer diameter of three types of wood with different hardness, such as larch (hard), cypress (slightly hard), and cedar (soft). In the case of hard larch, when the outer diameter of the tree W is in the range of 10 cm to 25 cm, the set rotation speed for the engine 8 is the standard rotation speed. When the outer diameter of the tree W is in the range of 0 to 10 cm, the set rotation speed for the engine 8 is 100 rpm less than the standard rotation speed. When the outer diameter of the tree W is in the range of 25 cm to 35 cm, the set rotation speed for the engine 8 is 100 rpm more than the standard rotation speed. When the outer diameter of the tree W is in the range of 35 cm to 55 cm, the set rotation speed for the engine 8 is 200 rpm more than the standard rotation speed.

In the case of slightly hard cypress, when the outer diameter of the tree W is in the range of 20 cm to 35 cm, the set speed of the engine 8 is the standard speed. When the outer diameter of the tree W is in the range of 0 to 20 cm, the set speed of the engine 8 is 100 rpm less than the standard speed. When the outer diameter of the tree W is in the range of 35 cm to 45 cm, the set speed of the engine 8 is 100 rpm more than the standard speed. When the outer diameter of the tree W is in the range of 45 cm to 55 cm, the set speed of the engine 8 is 200 rpm more than the standard speed.

In the case of soft cedar, when the outer diameter of the tree W is in the range of 25 cm to 45 cm, the set speed of the engine 8 is the standard speed. When the outer diameter of the tree W is in the range of 0 to 25 cm, the set speed of the engine 8 is 100 rpm less than the standard speed. When the outer diameter of the tree W is in the range of 45 cm to 55 cm, the set speed of the engine 8 is 100 rpm more than the standard speed.

The timber processing machine 11 according to this embodiment is equipped with the input device 41 described above. Before using the timber processing machine 11 to convert felled trees W into logs, the operator operates the input device 41 attached to the operation monitor (not shown) inside the cab 10. As a result, as shown in Figure 14, the engine speed when cutting the trees W with the chainsaw 31 is input in advance to the controller 37 as a set speed that is increased or decreased from the standard speed depending on the outer diameter and hardness of the trees W.

Here, we will explain the case where the tree W is a cedar. In the first step of the timber processing process shown in Figure 15, if the outer diameter of the root W1 side of the tree W held by the tongs 19, 20 is in the range of 35 to 40 cm, and in the second step, if the outer diameter of the tree W is in the range of 30 to 35 cm, the increase/decrease in engine speed input from the input device 41 to the controller 37 will be 0. Therefore, in the first and second steps, the chainsaw 31 is driven with the engine 8 maintaining the standard speed, and the tree W is cut.

In the subsequent third step, if the outer diameter of the tree W is in the range of 20 to 25 cm, and in the fourth step, if the outer diameter of the tree W is in the range of 5 to 10 cm, the increase/decrease in engine speed input from the input device 41 to the controller 37 is -100 min ^-1 . As a result, in the third and fourth steps, the chainsaw 31 is driven with the speed of the engine 8 reduced by 100 rpm from the standard speed, and the tree W is cut.

Next, a case where the tree W is a larch will be described. In the first step of the lumber production process shown in Figure 16, if the outer diameter of the root W1 side of the tree W held by the tongs 19, 20 is in the range of 35 to 40 cm, the increase/decrease in engine speed input from the input device 41 to the controller 37 is 200 min ^-1 . Therefore, in the first step, the chainsaw 31 is driven with the engine 8 speed increased by 200 rpm above the standard speed, and the tree W is cut.

In the subsequent second step, the tree W is fed by a certain length toward the cutting device 30 by the feeding device 22, and then the tree W is cut by the chainsaw 31. When the tree W is fed by the feeding device 22, the engine 8 maintains the standard rotation speed. On the other hand, when the tree W is cut by the chainsaw 31, if the outer diameter of the tree W is in the range of 30 to 35 cm, the increase/decrease in the engine rotation speed input from the input device 41 to the controller 37 is 100 min ⁻¹ . Therefore, in the second step, the chainsaw 31 is driven with the rotation speed of the engine 8 increased by 100 rpm from the standard rotation speed, and the tree W is cut.

In the following third step, the tree W is fed by the feeder 22 while the engine 8 maintains the standard rotation speed, and then cut by the chainsaw 31. At this time, if the outer diameter of the tree W is in the range of 20 to 25 cm, the increase/decrease in engine rotation speed input to the controller 37 from the input device 41 will be 0. Therefore, in the third step, the chainsaw 31 is driven while the engine 8 maintains the standard rotation speed, and the tree W is cut.

In the subsequent fourth step, the tree W is fed by the feeder 22 while the engine 8 maintains the standard rotation speed, and then the tree W is cut by the chainsaw 31. At this time, if the outer diameter of the tree W is in the range of 5 to 10 cm, the increase/decrease value of the engine rotation speed input to the controller 37 from the input device 41 is -100 min ^-1 . Therefore, in the fourth step, the chainsaw 31 is driven with the rotation speed of the engine 8 reduced by 100 rpm from the standard rotation speed, and the tree W is cut.

In this way, in the timber processing device 11 according to this embodiment, the input device 41 inputs multiple set rotation speeds for the engine 8 to the controller 37, taking into account not only the outer diameter of the tree W but also the hardness that varies depending on the tree species. This makes it possible to control the rotation speed of the engine 8 that drives the chainsaw 31, taking into account not only the outer diameter of the tree W but also the hardness of the tree W, which varies depending on the tree species. As a result, when cutting the tree W using the chainsaw 31, the rotation speed of the engine 8 can be accurately controlled in accordance with the outer diameter and hardness of the tree W, improving the quality of the logs cut from the tree W.

Thus, in this embodiment, the system comprises a self-propelled lower traveling body 2 and upper rotating body 4 equipped with an engine 8 that drives a hydraulic pump, a front device 5 attached to the upper rotating body 4, and a log processing device 11 attached to the front device 5 for processing trees W. The log processing device 11 is a hydraulic excavator 1 having a chainsaw 31 driven by pressurized oil discharged from the hydraulic pump and cutting the trees W. The log processing device 11 is equipped with an angle sensor 35 that detects the outer diameter of the trees W and a controller 37 that controls the rotation speed of the engine 8 in accordance with the outer diameter of the trees W detected by the angle sensor 35.

With this configuration, when using the chainsaw 31 to cut multiple logs from a single tree W, the engine 8 rotation speed can be automatically increased above the standard rotation speed when the outer diameter of the tree W to be cut is large, and the engine 8 rotation speed can be automatically decreased below the standard rotation speed when the outer diameter of the tree W to be cut is small. As a result, when cutting a tree W using the chainsaw 31, the operator does not need to perform the tedious task of increasing or decreasing the engine 8 rotation speed depending on the outer diameter of the tree W, improving workability during cutting.

In this embodiment, an input device 38 (41) is connected to the controller 37, which inputs multiple set rotation speeds for the engine 8 that are set according to the outer diameter of the tree W. The controller 37 increases or decreases the rotation speed of the engine 8 based on the outer diameter of the tree W detected by the angle sensor 35 and the set rotation speed of the engine 8 input by the input device 38 (41). With this configuration, by operating the input device 38 (41), the engine rotation speed when cutting the tree W with the chainsaw 31 can be input in advance to the controller 37 as a set rotation speed according to the outer diameter of the tree W.

In this embodiment, the controller 37 increases or decreases the rotation speed of the engine 8 based on the outer diameter of the tree W detected by the angle sensor 35 and multiple set rotation speeds of the engine 8 input from the input device 41, taking into account the outer diameter of the tree W and the hardness of the tree W. With this configuration, the rotation speed of the engine 8 can be controlled taking into account not only the outer diameter of the tree W but also the hardness of the tree W, which varies depending on the tree species, thereby improving the quality of the logs cut from the tree W.

In this embodiment, the timber processing device 11 has a gripping device 18 that grips the tree W from the outer periphery, and the angle sensor 35 is provided on the gripping device 18. With this configuration, when the tongs 19, 20 that make up the gripping device 18 grip the tree W, the angle sensor 35 detects the opening degree of the tongs 19, so the outer diameter of the tree W can always be detected according to the opening degree of the tongs 19.

In the embodiment, a timber processing device 11, generally called a processor, is exemplified, which performs timber processing work such as pruning and cutting felled trees. However, the present invention is not limited to this, and can also be applied to a timber processing device called a harvester, which performs timber processing work such as felling, pruning, and cutting trees (standing trees).

In addition, in the embodiment, an angle sensor 35 serving as an outer diameter detector is provided on the tong connecting pin 19A of the tongs 19 that constitute the gripping device 18, and the outer diameter of the tree W is detected based on the opening degree of the tongs 19. However, the present invention is not limited to this, and, for example, an angle sensor may be provided on the arm connecting pin 23A of the feeder arm 23 that constitutes the feeder 22, and the outer diameter of the tree W may be detected based on the opening degree of the feeder arm 23. Furthermore, the outer diameter of the tree W may be detected by capturing an image of a cross section of the tree W using a camera attached to the timber frame 13, for example, and analyzing this image.

1 Hydraulic excavator 2 Undercarriage (vehicle body)
4. Upper rotating body (car body)
5 Front device 8 Engine (prime mover)
11 Material processing device 18 Gripping device 31 Chainsaw (cutting machine)
35 Angle sensor (outer diameter detector)
37 Controller 38, 41 Input device

Claims (3)

The present invention comprises a self-propelled vehicle body equipped with a prime mover that drives a hydraulic pump, a front device provided on the vehicle body, and a timber processing device provided on the front device for processing trees,
The lumber processing device is a work machine having a cutting machine that is driven by pressure oil discharged from the hydraulic pump and cuts the trees,
The timber processing machine includes a feeding device that grips the tree and feeds it toward the cutting machine, an outer diameter detector that detects the outer diameter of the tree, and a controller that controls the rotation speed of the motor in accordance with the outer diameter of the tree detected by the outer diameter detector .
a controller that, when cutting the tree with the cutting machine, increases the rotation speed of the prime mover from the standard rotation speed as the outer diameter of the tree detected by the outer diameter detector increases, and, when feeding the tree with the feeding device, returns the rotation speed of the prime mover to the standard rotation speed . an input device is connected to the controller for inputting a plurality of set rotation speeds of the motor that are set according to the outer diameter of the tree;
2. The work machine according to claim 1, wherein the controller increases or decreases the rotation speed of the prime mover based on the outer diameter of the tree detected by the outer diameter detector and the set rotation speed of the prime mover input by the input device. The work machine described in claim 1, characterized in that the timber processing device has a gripping device that grips the tree from the outer periphery, and the outer diameter detector is provided on the gripping device.