JP5490504B2 - Backpack type power work machine - Google Patents

Description

  The present invention relates to a backpack-type power working machine such as a power brush cutter for cutting off vegetation such as weeds or a power cutter for cutting a surface such as a hedge uniformly.

  As this type of power working machine, Patent Document 1 discloses a backpack-type power brush cutter that can cut off vegetation such as weeds while carrying a power source. This shoulder-type power brush cutter includes an operation tube extending in a longitudinal shape, a rotating work body supported at the tip of the operation tube, a small gasoline engine as a power source supported by a backpack frame, and a base of the operation tube. A flexible tube that connects the end and the engine, and a transmission shaft that is connected to the output shaft of the engine and is inserted through the flexible tube or the operation tube to transmit the rotational output of the engine to the rotating work body. The transmission shaft has flexibility at least in a portion extending from the flexible tube to the operation tube. The operation tube is provided with a grip handle for swinging the operation tube so as to protrude on both the left and right sides.

  The mowing operation is performed by the operator who supports the engine with the back frame on the back side of the body swings the operation tube and moves the rotating work body along the ground. According to such a shoulder type power brush cutter, since the engine that occupies a large proportion of the weight is supported by the worker's body, the load due to the weight of the engine is not applied to both arms of the worker, The weight of the operation tube that is felt when a person swings is relatively light. Therefore, the cutting operation on the flat ground by such a backpack type power brush cutter can be performed relatively lightly and is less fatigued.

JP 2004-194521 A

  By the way, the place which is the object of the mowing work is not always flat, but may be a slope. Specifically, there is a slope such as a bank having a relatively large slope of 50 degrees or more and a slope length of about 3 m. In such a case, in order to make the rotating work body parallel to the slope, for example, it is necessary to lift the operating tube or rotate the operating tube around its axis so that the rotating work body is inclined to the left and right. is there.

  As described above, this type of backpack-type power brush cutter has an engine and an operation tube supported by a backpack frame, which are connected by a flexible tube and a flexible transmission shaft inserted through the flexible tube. The operation tube has a high degree of freedom, and the operation of swinging the operation tube along the flat ground is relatively easy to perform.

  However, although the flexible tube has flexibility, it plays a role as a member for connecting the engine and the operation tube, and stably rotates the transmission shaft inserted therein. Because it is necessary, it has a certain thickness and tensile strength. Therefore, a flexible tube produces a certain amount of resistance in bending deformation and twisting deformation. The flexible tube is fixedly connected to the operation tube. For this reason, in a swinging operation performed by lifting the operation tube, deformation resistance of the flexible tube may be a factor that hinders the operation.

  Specifically, for example, if the operating tube is lifted so that the rotating work body is placed higher than the waist position of the operator, the angle formed by the operating tube and the flexible tube becomes large and the flexible tube is bent and deformed. The resistance due to this bending deformation acts on the proximal end of the operation tube, making it difficult to lift. In addition, the weight of the rotating work body provided at the distal end of the operation tube is applied to both arms of the operator as a moment according to the distance from the distal end of the operation tube to the position of the grip handle. It will be difficult to lift. Also, if the grip handle protruding to the left and right sides is gripped with the left and right hands, both the arms of the operator will be extended, so change the direction of the rotating work body by rotating the operation tube around the axis. It is not easy. For these reasons, it is almost impossible to lift the operation tube higher than the waist position of the operator, and even if it is lifted, it feels quite heavy to rotate. Therefore, the conventional backpack type power brush cutter has a disadvantage that it is unsuitable for a brush cutting work on an inclined ground such as a bank or at a high position.

  Another problem is that the higher the tip of the operation tube is lifted, the greater the bending deformation of the flexible tube. As a result, the transmission shaft rotates while contacting the inner wall of the flexible tube. There is a problem that the output is wasted and the flexible tube is easily heated.

  The present invention has been conceived under the circumstances as described above, and can be easily operated on an inclined land or a high position, and can be operated comfortably while suppressing unreasonable heat generation of the flexible tube. It is an object to provide a backpack-type power work machine capable of performing the above.

  In order to solve the above problems, the present invention takes the following technical means.

  A backpack-type power working machine provided by the present invention includes an operation tube extending in a longitudinal shape, a work body supported at the tip of the operation tube, a power source supported by a backpack frame, and one end connected to the power source. A flexible tube having the other end connected to the proximal end of the operation tube, and the flexible tube or the operation tube. The rotation output of the power source is transmitted to the work body to A backhaul type power working machine including a transmission shaft having flexibility at least a portion extending from the flexible tube to the operation tube, and being operated at a proximal end of the operation tube. A grip that is provided and held by an operator's hand and the other end of the flexible tube are connected to the proximal end of the operation tube so as to be rotatable within a predetermined angular range around a horizontal rotation axis. The movable connecting mechanism and the intermediate portion of the operation tube are operated by the operator's hand. Is characterized by comprising a handle that is gripped to suspend the tube, the.

  As a preferred embodiment, one end of the flexible tube is connected to the power source via a connecting member that can rotate in the axial direction of the transmission shaft.

  As a preferred embodiment, the other end of the flexible tube is also rotatably connected to the movable connecting mechanism.

  As a preferred embodiment, the grip is an external fitting grip provided so as to surround the operation tube.

  As a preferred embodiment, the grip includes an outer fitting grip provided so as to surround the operation tube, and a side grip provided near the front end of the outer fitting grip so as to extend to one side in the lateral direction of the operation tube. There are two types.

  As a preferred embodiment, the external fitting grip is provided with an extending portion extending downward from the movable coupling mechanism.

  As a preferred embodiment, a support arm extending upward and rearward of the operation tube is provided at the proximal end of the operation tube, and an operation for gripping the grip is provided at the distal end of the support arm. An elbow support member that receives a person's forearm from below is supported.

  As a preferred embodiment, a support arm that extends upward and rearward of the operation tube is provided at the proximal end of the operation tube, and the grip extends to one side in the lateral direction of the operation tube. It is a side grip provided on the support arm.

  As a preferred embodiment, the side grip is provided on the rear side of the rotating shaft of the movable connecting mechanism.

  As a preferred embodiment, an elbow support member that receives the forearm of an operator holding the side grip from below is supported at the tip of the support arm.

  As a preferred embodiment, an operation unit for controlling the rotational output of the power source is provided in the vicinity of the grip.

  As a preferred embodiment, the handle is a loop handle having a loop shape above the operation tube.

  As a preferred embodiment, the power source is supported so as to be rotatable about a rotation axis extending in the vertical direction with respect to the back frame.

  As a preferred embodiment, the working body is a rotary blade for brush cutting.

  As a preferred embodiment, the rotary blade is rotatable with respect to the operation tube around a rotation axis extending in a direction intersecting the rotation axis of the movable coupling mechanism in the axial direction of the operation tube. It is supported.

  As a preferred embodiment, the rotating shaft is substantially orthogonal to the rotating shaft of the movable connecting mechanism when the operating tube is viewed in the axial direction.

  As a preferred embodiment, the working body is a hedge trimmer having a reciprocating shear blade.

  According to such a configuration, for example, when the operation tube is lifted so as to place the work body up to a position higher than the waist position of the operator, the proximal end of the operation tube is generally directed downward. At this time, the flexible tube connected to the proximal end of the operation tube via the movable connection mechanism is connected to be rotatable around a horizontal rotation axis, and thus is relatively small with respect to the operation tube. Bending and relieving the bending deformation. Thereby, the resistance force by the bending deformation of the flexible tube hardly acts on the proximal end of the operation tube. In addition, the operator holds the grip provided at the proximal end of the operation tube with one hand, and hangs the handle provided at the intermediate portion of the operation tube with the other hand as a fulcrum. Can be gripped. As a result, the operator can easily hold the control tube by holding the grip and handle with both hands, and even if the tip of the control tube is raised higher, the weight of the work body provided at the tip is reduced. The operating tube can be easily lifted without feeling heavy. Further, when the operation tube is lifted, the operation tube and the flexible tube are connected via the movable connecting mechanism, so that the flexible tube is prevented from being bent to an unreasonable degree with respect to the operation tube. Reduction in rotational output and heat generation due to long-term contact of the transmission shaft with the pipe are prevented.

  Therefore, according to the shoulder-type power working machine according to the present invention, an operator can perform a light operation while lifting the operation tube with respect to an inclined ground or a high position, and suppress unjustified heat generation of the flexible tube. You can work comfortably.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

1 is an overall perspective view showing a first embodiment of a backpack type power working machine. It is a principal part disassembled perspective view of the shoulder type power working machine shown in FIG. It is a principal part side view of the backpack type power working machine shown in FIG. It is principal part side surface sectional drawing of the backpack type power working machine shown in FIG. FIG. 2 is a top cross-sectional view of the main part of the shoulder-type power working machine shown in FIG. It is a perspective view for demonstrating the usage example of the shoulder-type power working machine shown in FIG. It is a perspective view for demonstrating the usage example of the shoulder-type power working machine shown in FIG. It is a whole perspective view which shows 2nd Embodiment of a backpack type power working machine. It is a principal part disassembled perspective view of the shoulder type power working machine shown in FIG. It is a principal part side view of the backpack type power working machine shown in FIG. It is principal part side surface sectional drawing of the backpack type power working machine shown in FIG. It is principal part top sectional drawing of the main part of the shoulder type power working machine shown in FIG. It is a perspective view for demonstrating the usage example of the backpack type power working machine shown in FIG. It is a perspective view for demonstrating the usage example of the backpack type power working machine shown in FIG. It is principal part side sectional drawing which shows 3rd Embodiment of a backpack type power working machine. FIG. 16 is a top cross-sectional view of the main part of the shoulder-type power working machine shown in FIG. It is a principal part disassembled perspective view which shows 4th Embodiment of a backpack type power working machine. It is a principal part side view of the backpack type power working machine shown in FIG. FIG. 18 is a top cross-sectional view of the main part of the shoulder-type power working machine shown in FIG. 17. It is a perspective view for demonstrating the usage example of the shoulder type power working machine shown in FIG. It is a perspective view for demonstrating the usage example of the shoulder type power working machine shown in FIG. It is a whole perspective view which shows 5th Embodiment of a backpack type power working machine.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  1-7 has shown 1st Embodiment of the shoulder-type power working machine. The shoulder-type power working machine A1 according to the present embodiment is a shoulder-type power working machine that can trim plants such as weeds by a working body that rotates while carrying a power source. As shown in FIG. 1, the backpack-type power working machine A1 includes a backpack frame 1, an engine 2 as a power source, an operation tube 3 extending in a longitudinal shape, a rotary blade B as a working body, an engine 2 and an operation tube 3, A flexible tube 5 connecting the control tube 3, a transmission shaft 6 inserted through the flexible tube 5 (see FIGS. 4 and 5), a movable connecting mechanism 7 for connecting the control tube 3 and the flexible tube 5, and the engine 2. And a connecting member 8 for connecting the flexible tube 5 to each other.

  An engine 2 is mounted on the back frame 1. A rotary blade B is supported on the tip 3 </ b> A of the operation tube 3. At the proximal end of the operation tube 3, an external fitting grip 30 for gripping the operation tube 3 by an operator's hand and the rotation output of the engine 2 in the vicinity of the external fitting grip 30 are controlled. An operation unit 31 is provided. An elbow support member 32 for receiving the forearm of the operator who holds the external fitting grip 30 from below is provided via a support arm 320 and a fixing member 40 at the proximal end of the operation tube 3. A loop handle 33 is provided at an intermediate portion of the operation tube 3 for gripping the operation tube 3 so as to be suspended by an operator's hand. The transmission shaft 6 passes through the connecting member 8 from the engine 2 and is inserted into the flexible tube 5, and further passes through the movable connecting mechanism 7 and is inserted into the operation tube 3. Up to 3A. A transmission shaft 6 is connected to the rotation shaft of the rotary blade B through a bevel gear mechanism (not shown) at the distal end portion 3A of the operation tube 3.

  The back frame 1 includes an engine mounting portion 10, a band member 11 that hangs on both shoulders of the worker, and a cushion member 12 that comes into contact with the back of the worker. The engine mounting portion 10 is formed by using a frame pipe or the like, and the engine 2 is supported by the engine mounting portion 10 so as to be rotatable around a rotation axis P along the vertical direction. The band member 11 is locked to an appropriate portion of the frame pipe of the engine mounting portion 10 and is attached to an operator in the same manner as carrying a rucksack, for example. The cushion member 12 is attached to the front portion of the frame pipe of the engine mounting portion 10, and abuts against the back of the operator wearing the band member 11 to relieve the pressure of the engine mounting portion 10.

  As the engine 2, for example, a small two-cycle gasoline engine is applied. The engine 2 is rotatable around a rotation axis P in the vertical direction while being supported by the frame pipe of the engine mounting portion 10. An output shaft of the engine 2 (not shown) extends to the rear of the engine mounting portion 10. The flexible tube 5 is connected to the engine 2 through the connecting member 8. The base end of the transmission shaft 6 extending from the flexible tube 5 to the rear portion of the engine 2 through the inside of the connecting member 8 is connected to the output shaft of the engine 2 via a clutch mechanism (not shown). As a result, when the rotational output of the engine 2 reaches a certain level or higher, the clutch shaft is operated to rotate the transmission shaft 6, thereby rotating the rotary blade B supported by the distal end portion 3 </ b> A of the operation tube 3. Let

  The operation tube 3 is formed of, for example, a relatively lightweight and hollow metal pipe. A bevel gear mechanism (not shown) is built in the distal end portion 3A of the operation tube 3, and the rotating shaft (not shown) of the rotary blade B and the tip of the transmission shaft 6 have a predetermined angle via the bevel gear mechanism. Connected. The loop handle 33 provided in the intermediate portion of the operation tube 3 has a loop shape that is easy to hold by hanging so that the tip portion 3A of the operation tube 3 is raised upward. As shown in FIGS. 2 to 5, an outer fitting grip 30, an operation unit 31, an elbow support member 32, a support arm 320, a fixed member 40, and a movable coupling mechanism 7 are provided at the proximal end of the operation tube 3. . As shown in FIGS. 4 and 5, for example, a holding tube 35 that is supported via an anti-vibration spacer 34 made of rubber is inserted into the operation tube 3. The transmission shaft 6 is inserted into the holding tube 35 so as to be rotatable. As a result, the transmission shaft 6 in the operation tube 3 is held straight along the operation tube 3 and smoothly rotated. In addition, it is good also as a structure which can rotate the front-end | tip part of an operation pipe | tube around a horizontal axis like what is shown by the patent 4012492 gazette or the patent 3806384 gazette. In a shoulder-type power working machine employing such a configuration, the angle of the rotary blade with respect to the operation tube is appropriately changed by adjustment by the operator or by hitting the rotary blade against the ground. For example, the rotary blade is parallel to the operation tube. Can be up to posture.

  As shown in FIGS. 3 and 4, the external fitting grip 30 is a substantially cylindrical member that is easy for an operator to hold with one hand, and is externally fitted to the proximal end so as to surround the operation tube 3. The external fitting grip 30 includes a gripping portion 300, an extending portion 301, a hollow portion 302 (see FIG. 4), and a long hole portion 303 (see FIG. 4). The gripping part 300 is a cylindrical part that can be gripped with one hand, and has a hollow part 302 and a long hole part 303 therein. An extension part 301 that extends outward from the openings of the hollow part 302 and the long hole part 303 and is inclined downward toward the tip is provided at the lower part on the rear end side of the grip part 300. . The extension portion 301 extends downward from the movable coupling mechanism 7. The lower part of the extension part 301 is formed in a wave shape so that a plurality of fingers can be easily attached. The upper part on the rear end side of the gripping part 300 is greatly raised toward the rear end. The proximal end of the operation tube 3 is inserted into the hollow portion 302. An accelerator operation cable 305 (see FIG. 4) is inserted through the long hole portion 303. When the operator holds the operation tube 3, one hand holding the outer fitting grip 30 is always closer to the body than the hand holding the other loop handle 33, so that the arm holding the outer fitting grip 30 has a margin, The operation unit 31 can be operated while holding the operation tube 3 relatively easily. For example, when lifting the tip 3 </ b> A of the operation tube 3 upward, the hand can be moved to the extension 301 to grip the external fitting grip 30.

  As shown in FIG. 4, the operation unit 31 is connected to the engine 2 via an accelerator operation cable 305, and an operation main body 310 into which an internal wire (not shown) of the accelerator operation cable 305 is drawn, and its internal wire Is provided with an L-shaped accelerator lever 311 that raises the rotational output of the engine 2 by pulling. When the operation main body 310 is attached to the operation tube 3, the operation main body 310 extends to some extent above at least the upper part of the front end of the external fitting grip 30. For example, when the front end of the external fitting grip 30 is gripped, the hand comes into contact with the upper rear end of the operation main body 310. Therefore, the operation main body 310 also functions as an anti-slip hand for gripping the external fitting grip 30. The accelerator lever 311 has a bent shape extending from the lower side to the upper side of the operation main body 310, and the tip of the internal wire is locked to the lower part. As shown by a solid line in FIG. 3, the accelerator lever 311 is always positioned on the front side due to the elastic force of a spring (not shown), for example, when it is in a natural state without any operation. As indicated by the phantom line in the figure, when the operator moves the accelerator lever 311 rearward with the thumb of the hand holding the external fitting grip 30, the internal wire of the accelerator operation cable 305 is pulled, and the rotation output of the engine 2 is output. Is raised. When the accelerator lever 311 is appropriately moved, the accelerator lever 311 remains in its position by, for example, frictional locking. Therefore, the operator does not always have to operate the accelerator lever 311. The accelerator lever of the operation unit may be of a type such as a bicycle brake lever or a friction shift lever.

  As shown in FIGS. 2 and 7, the elbow support member 32 receives the forearm from below that holds the outer fitting grip 30 when the operation tube 3 is held with the distal end portion 3 </ b> A of the operation tube 3 facing downward. There is a substantially U-shaped cross section so that the forearm base of the operator fits perfectly. The elbow support member 32 is supported at the tip of the support arm 320. A screw hole 321 for fixing the support arm 320 to the fixing member 40 with a screw (not shown) is provided at the base end of the support arm 320. When the support arm 320 is attached to the operation tube 3 via the fixing member 40, the support arm 320 has a symmetrical posture with respect to the extension portion 301 of the outer fitting grip 30 with respect to the operation tube 3, and the elbow support member As it moves toward the fixed tip 32, it is inclined upward. As a result, a space is secured between the support arm 320 and the extending portion 301 so that the movable connecting mechanism 7 can rotate in the vertical direction within a predetermined angle range. When the operator grips the outer fitting grip 30 with the distal end portion 3A of the operation tube 3 facing downward, the forearm that grips the outer fitting grip 30 looks good along the support arm 320, and the forearm base near the elbow is Just fit into the elbow support member 32.

  As shown in FIGS. 6 and 7, the loop handle 33 is easy to give a hand force necessary for lifting the operating tube 3 or swinging the operating tube 3 left and right to the operating tube 3. For example, when the operation tube 3 is lifted as shown in FIG. 6, the operator holds the outer fitting grip 30 with the right hand and hangs the loop handle 33 with the left hand while using the holding position as a fulcrum. It can be gripped. At that time, both hands of the operator are positioned on the axis of the operation tube 3 and are held in the most easy way to lift the operation tube 3. When the operator has the proximal end of the operation tube 3 as much as possible, the operator grips the portion from the proximal end of the support arm 320 to the extended portion 301 of the outer fitting grip 30 so as to hold the outer fitting grip 30. It is possible to grip the rear end side. As a result, even if the operator raises the tip 3A of the operation tube 3 high, the operator does not feel the weight of the rotary blade B provided at the tip 3A so much. It can be lifted in a stable posture by pulling it closer to. The handle provided at the intermediate portion of the operation tube is not limited to the loop type, and any handle can be used as long as the operation tube can be suspended. For example, the shape of the handle may be U-shaped so as to extend laterally from the intermediate portion of the operation tube and further to the upper portion of the intermediate portion. You can hold the part to hang.

  As shown in FIGS. 2 to 4, the fixing member 40 fixes the elbow support member 32 to the proximal end of the operation tube 3 via the support arm 320, and the movable connection mechanism to the proximal end of the operation tube 3. 7 is for inserting and fixing a part of 7. The fixing member 40 also abuts on the rear end of the external fitting grip 30 in a state where the fixing member 40 is fixed to the proximal end of the operation tube 3, and thus serves to prevent the external fitting grip 30 from coming off from the operation tube 3. The fixing member 40 includes an upper portion 400 to which the proximal end of the support arm 320 is fixed, a fitting portion 401 into which the proximal end of the operation tube 3 is fitted, a cut groove 402 reaching the fitting portion 401 from the upper portion 400, and the cut groove 402 in the lateral direction. And an annular groove 404 for locking a cover 72 described later. The upper part 400 is provided with an inclined surface that is closer to the rear. The support arm 320 is attached along the inclined surface of the upper portion 400, and thus is inclined with respect to the operation tube 3. The fixing member 40 is fixed as follows. First, the outer fitting grip 30 and the operation portion 31 are attached to the proximal end of the operation tube 3 so as to be fitted, and then a part of the movable coupling mechanism 7 is disposed on the proximal end of the operation tube 3. (Cylinder portion 700 described later) is inserted. Next, the fitting portion 401 of the fixing member 40 is fitted to the outer peripheral surface portion of the operation tube 3 into which a part of the movable coupling mechanism 7 is inserted so as to fit this portion. The rear end surface of the fixing member 40 is substantially matched with the end surface of the operation tube 3. Thereafter, the base end of the support arm 320 is disposed on the upper portion 400 of the fixing member 40, and screws (not shown) are fastened and fixed to the screw holes 321 of the support arm 320 and the screw holes 403 of the fixing member 40. . That is, the fixing member 40 is fastened and fixed to the proximal end of the operation tube 3 with the cut groove 402 being crushed. As a result, the outer peripheral surface portion of the operation tube 3 in contact with the fitting portion 401 of the fixing member 40 is uniformly tightened, and a part of the movable coupling mechanism 7 is also strongly tightened by the inner peripheral surface portion of the operation tube 3. As a result, the support arm 320 and the movable coupling mechanism 7 are securely fixed to the proximal end of the operation tube 3 via the fixing member 40.

  As shown in FIGS. 2 to 5, the movable connecting mechanism 7 connects one end of the flexible tube 5 to the proximal end of the operation tube 3 so as to be rotatable around the rotation axis S. The first member 70 on the side, the second member 71 on the flexible tube side, and a cover 72 that covers these connecting portions are provided. The cover 72 is, for example, a tube having a high flexibility. The first member 70 and the second member 71 are configured to be able to rotate with respect to each other within a certain angular range around a horizontal horizontal rotation axis S orthogonal to the axis of the operation tube 3 by the following configuration. It is connected to.

  The first member 70 includes a cylindrical portion 700 that is fitted into the proximal end of the operation tube 3 so as not to be axially rotatable, and a connecting portion 701 that extends rearward from the cylindrical portion 700. A tapered through hole 702 that expands in the direction in which the second member 71 rotates as it approaches the connecting portion 701 is formed inside the cylindrical portion 700. The connecting portion 701 is formed so as to form a pair of left and right opposing walls, and the opening of the through hole 702 is positioned between these opposing walls. A screw hole 704 is formed in the connecting portion 701. A restriction edge 705 for restricting the rotation range of the second member 71 is formed at the tip of the connecting portion 701. A step portion 703 having an outer diameter larger than that of the operation tube 3 is formed between the tube portion 700 and the connecting portion 701. The cylindrical portion 700 is fixed by being inserted into the operation tube 3 until the stepped portion 703 contacts the rear end surface of the fixing member 40 or the end surface of the operation tube 3.

  The second member 71 includes a cylindrical portion 710 that fits the distal end of the flexible tube 5 and a bracket portion 711 that extends forward from the cylindrical portion 710. Inside the cylindrical portion 710, a fitting hole 712 for fitting the tip of the flexible tube 5 so as not to be pivotable, and a taper-shaped penetration that expands in a direction in which the bracket portion 711 rotates as it approaches the bracket portion 711. A hole 713 is formed. The bracket part 711 is formed so as to form a pair of left and right opposing walls on which the connecting part 701 of the first member 70 can be arranged, and an opening of the through hole 713 is located between these opposing walls. The bracket part 711 is provided with a screw hole 714 corresponding to the screw hole 704 of the connecting part 701. A tip 715 of the bracket portion 711 is formed in an arc shape so that the bracket portion 711 moves smoothly without coming into contact with the step portion 703 of the first member 70. Such a second member 71 is formed by fitting the bracket portion 711 to the connecting portion 701 of the first member 70 and tightening the screw 73 having the screw hole 714 penetrated into the screw hole 704, thereby fixing the first member 70 to the first member 70. It is connected so as to be rotatable. When the second member 71 rotates about the rotation axis S with respect to the first member 70, when the second member 71 rotates to a certain extent, the regulation edge 705 of the first member 70 hits the inner inner end face of the bracket portion 711. Thereby, the second member 71 can be rotated around the rotation axis S in an angle range of approximately ± 20 ° to 25 °. Therefore, the distal end of the flexible tube 5 connected to the cylindrical portion 710 of the second member 71 can also be rotated in the vertical direction within an angular range of approximately ± 20 ° to 25 °.

  The cover 72 includes an annular groove 716 formed on a part of the outer peripheral surface of the cylindrical portion 710 of the second member 71 and an annular groove of the fixing member 40 in a state where the movable coupling mechanism 7 is fixed to the proximal end of the operation tube 3. The ring-shaped elastic band 720 is locked to 404 and sealed. Since a sealed space is formed inside the cover 72, a lubricant such as grease can be attached to the connecting portion of the first member 70 and the second member 71.

  The flexible tube 5 is inserted into, for example, a resin or synthetic rubber obtained by forming a metal core material wound in a coil shape into a cylindrical shape, and can be bent with a predetermined resistance against an axial pressure. It is. Such a flexible tube 5 is provided so as to connect the movable connecting mechanism 7 and the connecting member 8.

  The transmission shaft 6 passes through the connecting member 8 and extends inside the flexible tube 5, and further passes through the movable connecting mechanism 7 and extends to the distal end portion 3 </ b> A of the operation tube 3. Connected to the input shaft. At the distal end portion 3A of the operation tube 3, the output shaft of the bevel gear mechanism is changed in the axial direction of the operation tube 3 so as to be substantially along the direction in which the movable coupling mechanism 7 rotates (vertical direction). The rotating shaft of the rotary blade B is attached to the output shaft of the mechanism.

  The connecting member 8 has a configuration similar to that of the movable connecting mechanism 7, and includes a first member 80 on the engine side and a second member 81 on the flexible tube side. The first member 80 and the second member 81 are coupled so as to be rotatable around a rotation axis S ′ in a direction orthogonal to the direction through which the transmission shaft 6 passes within a certain angle range. The connecting member 8 rotates around the rotation axis S ′ by the same mechanism as the above-described movable connecting mechanism 7, and detailed illustration thereof is omitted. The first member 80 is connected to the rear portion of the engine 2 so as to be able to rotate about the axis X in the direction in which the transmission shaft 6 penetrates. As shown in FIG. 1, the second member 81 rotates in the left-right direction with respect to the first member 80 by rotating around the rotation axis S ′ when the rotation axis S ′ is in the vertical direction. Swing. Thereby, the proximal end of the flexible tube 5 connected to the connecting member 8 has a high degree of freedom in the extending direction. For example, when the entire flexible tube 5 hangs down due to its own weight, the first member 80 rotates in a direction to receive a force due to the bending deformation of the flexible tube 5, and accordingly the rotation axis S ′ is inclined to some extent from the vertical direction. It becomes a posture. When the rotation axis S ′ is inclined from the vertical direction, the second member 81 is easily bent downward with respect to the first member 80. Further, the rear portion of the engine 2 to which the connecting member 8 is connected is rotated around the rotation axis P and swung left and right by receiving a force due to bending deformation of the flexible tube 5. Such a connecting member 8 and the movable structure of the engine 2 effectively relieve bending deformation of the flexible tube 5. In addition, you may make it cover the connection part of a connection member by providing the same cover as a movable connection mechanism.

  Next, the operation of the backpack type power working machine A1 will be described.

  FIG. 6 shows a case in which weeding work such as weeds is performed at a high position on a steep slope such as a bank with an inclination of 50 degrees or more. In the state as shown in the figure, the operator puts the back frame 1 on the back, holds the outer fitting grip 30 with the right hand, for example, and raises the loop handle 33 with the left hand higher than the holding position of the right hand. Hold it so that it hangs.

  At this time, the left and right hands of the operator are located on the axis of the operation tube 3. Thereby, the operator can lift the operation tube 3 straight without rotating it. Further, the operator can grip the rear end side of the outer fitting grip 30 as much as possible, and can hold the proximal end of the support arm 320 and the extending portion 301 of the outer fitting grip 30. In such a case, the hand holding the external fitting grip 30 is located in the vicinity of the movable coupling mechanism 7. Therefore, the operator can easily bend the movable coupling mechanism 7 in accordance with the bending deformation of the flexible tube 5, and the operator can push the hand with the external fitting grip 30 back and forth to tilt the operation tube 3. Can be easily changed. That is, when lifting the operation tube 3 upright, the operator can apply a force to the hand holding the external fitting grip 30 without feeling uncomfortable as being pulled by the flexible tube 5. 3 can be lifted in a stable posture. Even if the distal end portion 3A of the operation tube 3 is raised, the operator can adjust the inclination of the operation tube 3 by lightly operating the rear end of the external fitting grip 30. The posture can be approximately parallel to the slope. At this time, the operator does not feel the weight of the rotary blade B or the like so much that the load when lifting the operation tube 3 is reduced.

  In addition, the hand having the external fitting grip 30 is located in the vicinity of the movable coupling mechanism 7, but since the coupling portion of the movable coupling mechanism 7 is covered with the cover 72, the hand is soiled with a lubricant or the movable coupling mechanism There is no trouble in the operation of 7. As for the way to hold the external fitting grip 30 and the loop handle 33, a way that the operator can easily operate can be selected, and a hand holding direction opposite to the above may be used.

  When such a gripping posture is taken, the operation tube 3 has a configuration in which the distal end portion 3A is lifted upward, for example, higher than the waist position of the operator, and the rotary blade B is substantially parallel to the slope to be worked. become. The rotary blade B is rotated by transmitting the rotation output of the engine 2 to the transmission shaft 6 according to the operation of the accelerator lever 311 and rotating the transmission shaft 6 to operate a bevel gear mechanism (not shown). At that time, the operator can swing the distal end portion 3A of the operation tube 3 left and right, and can cut out weeds and the like over a wide range of slopes. As a result, the operator can easily mow the weeds and the like grown at a high position on the slope with the rotary blade B. Further, as an extreme example, even if the operation tube 3 is in a posture along the vertical direction, the operator can stably hold the operation tube 3 with a hand having the rear end of the external fitting grip 30 and a hand having the loop handle 33. Can be kept in.

  When the operation tube 3 is provided as described above, the operation tube 3 is positioned so as to extend from the front of the operator to the upper side. At this time, the movable coupling mechanism 7 is easily bent toward the elbow receiving member 32. Thereby, bending deformation of the flexible tube 5 is suppressed, and the flexible tube 5 is gently curved from the movable connecting mechanism 7 to the engine 2 located on the back side of the operator. The movable connecting mechanism 7 connects the operation tube 3 and the flexible tube 5 so as to be rotatable around a horizontal and horizontal rotation axis S. Therefore, when the operation tube 3 is lifted upward, the flexible tube 5 is bent and deformed. Does not change so much.

  Therefore, when the swing operation is performed by lifting the operation tube 3 so as to stand up, in addition to the way of holding the operation tube 3 as described above, useless resistance due to bending deformation of the flexible tube 5 is caused by the base of the operation tube 3. Since it is not applied to the edge, lightness is increased in the operation. Further, since the movable connecting mechanism 7 limits the bending deformation in the vertical direction of the flexible tube 5 with respect to the operation tube 3, the transmission shaft 6 inserted through the flexible tube 5 is not bent more than necessary. Thereby, useless resistance does not arise in the axial rotation of the transmission shaft 6, and the output reduction of the engine 2 can be suppressed. Since the through holes 702 and 713 of the first member 70 and the second member 71 through which the transmission shaft 6 is inserted in the movable connecting mechanism 7 are tapered so as to expand toward the locations where they are connected to each other, they are movable. Even if the coupling mechanism 7 is bent, it is possible to avoid the shaft 6 that rotates in rotation from coming into strong contact with the inner peripheral surfaces of the through holes 702 and 713. Also by this, generation | occurrence | production of the frictional heat and output fall by the transmission shaft 6 contacting the movable connection mechanism 7 can be suppressed.

  Further, the connecting member 8 for connecting the flexible tube 5 to the engine 2 enables the flexible tube 5 to rotate about the rotation axis S ′ and to rotate about the axis X with respect to the engine 2. The base end of the flexible tube 5 is swung in all directions, left, right, up and down, by the two-axis operation. The engine 2 is also rotatable around the rotation axis P and is swung in the left-right direction. As a result, when the operation tube 3 is swung in the vertical direction or the left-right direction, the bending deformation of the flexible tube 5 becomes as small as possible, and useless resistance due to the bending deformation is applied to the engine 2 and the back frame 1. There is nothing. Therefore, at the time of work, lightness is increased in the operation of the operation tube 3, and no wasteful resistance is generated in the rotation of the transmission shaft 6, and a decrease in the output of the engine 2 can be suppressed.

  Therefore, according to the shoulder type power working machine A1, the operation tube 3 is easily lifted higher than the waist position of the operator, and the flexible tube 5 can be bent and deformed even if the operation tube 3 is swung. The transmission shaft 6 can be kept as small as possible, and the transmission shaft 6 is not brought into contact with the flexible tube 5 for a long time. Therefore, the operator can perform a light operation while lifting the operation tube 3 with respect to an inclined ground or a high position, and can perform a work comfortably while suppressing unreasonable heat generation of the flexible tube 5.

  As described above, the bending deformation of the flexible tube 5 more than necessary can be prevented and the decrease in the output of the engine 2 can be suppressed, so that the engine 2 having a smaller output can be adopted. This contributes to further weight reduction of the shoulder-type power working machine A1 and leads to improvement in operability.

  FIG. 7 shows a case of performing a mowing work such as weeds on a flat ground. In the state shown in the figure, the operator holds the back frame 1 and grips the outer fitting grip 30 with the right hand, and the loop handle 33 with the left hand so that the grip is slightly lower than the gripping position of the right hand. Grip. In this case, the hand holding the external fitting grip 30 may hold the holding part 300 that is in front of the base end of the support arm 320. When such a gripping posture is taken, the forearm that grips the external fitting grip 30 extends along the support arm 320, and the vicinity of the elbow of the forearm just fits in the elbow receiving member 32. 3 A of front-end | tip parts of the operation tube 3 become the appearance which approached the ground of the flat ground used as a work object, and the rotary blade B becomes substantially parallel with respect to the ground. The rotary blade B is rotated according to the operation of the accelerator lever 311 as described above. At that time, the operator can mow off weeds and the like over a wide area of the flat ground by swinging the tip 3 </ b> A of the operation tube 3 left and right.

  At this time, the operation tube 3 is inclined downward from the proximal end toward the distal end portion 3A. The force for swinging and holding the operation tube 3 left and right is not only the left hand holding the loop handle 33 and the right hand holding the external fitting grip 30, but the forearm of the right hand holds the elbow support member 32 left and right. It can be transmitted to the operation tube 3 sufficiently effectively and effectively by pushing in the direction or downward. That is, the operation tube 3 is supported at three points by both hands of the operator and the elbow portion of the right arm, and is swung left and right in a stable posture. Further, the rotary blade B provided at the distal end portion 3A of the operation tube 3 is not brought closer to the ground than necessary, and a state where the rotary blade B rubs against the ground is avoided as much as possible. Thereby, the operator can lightly and easily mow the weeds etc. which grew on the flat ground with the rotary blade B. As described above, as to how to hold the external fitting grip 30 and the loop handle 33, of course, it may be a hand holding direction opposite to the above.

  Further, as the operation tube 3 is swung left and right, the connecting member 8 that connects the flexible tube 5 to the engine 2 rotates the flexible tube 5 around the rotation axis S ′ with respect to the engine 2. It is movable and can be rotated about the axis X, and the proximal end of the flexible tube 5 is swung in all directions, left, right, up and down, by these two-axis operations. The engine 2 is also rotatable around the rotation axis P and is swung in the left-right direction. Thereby, even in the operation of swinging left and right with the distal end portion 3A of the operation tube 3 facing downward, useless resistance due to the bending deformation of the flexible tube 5 is not applied to the engine 2 or the back frame 1. Lightness is increased in the operation of the operation tube 3, and unnecessary resistance is not generated in the rotation of the transmission shaft 6, so that a decrease in output of the engine 2 can be suppressed.

  Therefore, even in the mowing work on the flat ground using the shoulder-type power working machine A1, the operation tube 3 can be swung easily and easily, and the bending deformation of the flexible tube 5 can be suppressed as small as possible. It is possible to work comfortably while suppressing unreasonable heat generation of the flexible tube 5.

  Next, another embodiment will be described. In the following description, the same or similar components as those described above are denoted by the same reference numerals, and the description thereof is omitted.

  8-14 has shown 2nd Embodiment of the shoulder-type power working machine. The backpack type power working machine A2 of the present embodiment includes an outer fitting grip 30 and a side grip 30 'as two types of grips. The outer fitting grip 30, the elbow receiving member 32, the fixed member 40, the movable connecting mechanism 7, and the connecting member 8 differ in detail from those according to the first embodiment described above. Other configurations are the same as those according to the first embodiment described above.

  As shown well in FIGS. 9 to 11, the external fitting grip 30 is shorter than that described above, and is a size necessary and sufficient for an operator to hold the proximal end of the support arm 320 with one hand. An operator can inevitably have a portion in the vicinity of the movable coupling mechanism 7 by gripping the external fitting grip 30. When the operator holds the operation tube 3 in a posture in which the distal end portion 3A of the operation tube 3 is raised higher than the proximal end, as in the case of the first embodiment described above, the proximal end and the external fitting of the support arm 320 are provided. The extended portion 301 of the grip 30 can be gripped. Note that when lifting the operation tube 3, the operator does not necessarily have the external fitting grip 30, and may have a side grip 30 'as shown in FIG.

  As shown in FIG. 9, the side grip 30 ′ is a rod-like grip that can be changed by the operator from the external fitting grip 30, and is operated horizontally on one side with respect to the operation tube 3 (for example, as shown in FIG. 8). The tube 3 extends from the proximal end side to the right side when viewed from the distal end portion 3A. The side grip 30 ′ is supported on the proximal end side of the operation tube 3 via a support member 300 ′ fixed between the outer fitting grip 30 and the operation unit 31, and is located near the front end of the outer fitting grip 30. Is provided. As shown in FIG. 13 and FIG. 14, the operator can project the side projecting to the right at the proximal end of the operation tube 3 regardless of whether the distal end portion 3A of the operation tube 3 is at the high position or the low position. The grip 30 ′ can be gripped with the right hand, and the operation tube 3 can be swung left and right while being balanced with the left hand having the loop handle 33. At that time, the operator can hold the operation tube 3 in a balanced manner in the vertical and horizontal directions by holding the side grip 30 ′ with a so-called reverse hand. In addition, when lifting up the operation tube 3, you may have the external fitting grip 30 as mentioned above.

  As shown in FIGS. 8 and 9, the elbow support member 32 is supported on one end of the support arm 320 so as to be positioned on the same side as the side on which the side grip 30 ′ is disposed with respect to the operation tube 3. Yes. For example, as shown in FIG. 14, when the operator grips the side grip 30 ′ with the right hand, the forearm base near the elbow of the right hand is just within the elbow receiving member 32.

  As shown in FIGS. 9 and 12, the fixing member 40 fixes the base end of the support arm 320 with respect to the base end of the operation tube 3, and the cylindrical portion 700 of the first member 70 in the movable connection mechanism 7. The cylindrical portion 700 is fixed so that it cannot be rotated by a set screw 405 (see FIG. 12). A screw hole 406 for tightening a set screw 405 is provided at an appropriate portion of the fixing member 40. The set screw 405 is tightened into the screw hole 406 until it partially penetrates the operation tube 3 in the lateral direction and comes into contact with the cylindrical portion 700.

  As shown in FIGS. 9 to 12, the movable connecting mechanism 7 connects the distal end of the flexible tube 5 with respect to the proximal end of the operation tube 3 so as to be rotatable around the rotation axis S, as well as the flexible tube 5. Are connected so as to be rotatable about the axis T, which is the central axis of the cylindrical portion 710. The movable connecting mechanism 7 includes the first member 70 and the second member 71 as in the first embodiment, but the second member 71 is a component in which the cylindrical portion 710 and the bracket portion 711 are separate. Furthermore, it has the cap part 717 which connects the cylinder part 710 with respect to the bracket part 711 so that rotation around the axis T is possible.

  As shown well in FIG. 12, the cylindrical portion 700 of the first member 70 has an outer peripheral surface 700 </ b> A excluding an end portion formed in a conical shape, and further faces the screw hole 406 of the fixing member 40 on the outer peripheral surface 700 </ b> A. A step surface 700B is formed at the site. A tip end portion of a set screw 405 tightened in the screw hole 406 comes into contact with the step surface 700B. That is, when the step surface 700B is held down by the set screw 405, the first member 70 is securely fixed to the proximal end of the operation tube 3 so that it cannot rotate.

  As well shown in FIG. 12, the cylindrical portion 710 of the second member 71 has a large-diameter end portion 710 </ b> A on the side opposite to the flexible tube 5 that is connected so as not to rotate. The cap part 717 penetrates the cylinder part 710 to the rear side in the axial direction, and connects the end part 710A to the rear end surface of the bracket part 711 to restrict the axial movement of the end part 710A. The cap portion 717 is fixed to the rear end of the bracket portion 711 with a screw 711A while hooking the end portion 710A. Thus, a gap is formed between the cap portion 717 and the bracket portion 711 so that the end portion 710A can rotate around the axis T, and the cylindrical portion 710 integrated with the end portion 710A has It is connected so that it can rotate. The bracket portion 711 is connected to the connecting portion 701 of the first member 70 so as to be rotatable around the rotation axis S. As a result, the movable connecting mechanism 7 is configured such that one end of the flexible tube 5 can be rotated around the rotation axis S by the bracket portion 711 of the second member 71 with respect to the proximal end of the operation tube 3. By 710, it is possible to rotate around the axis T.

  The connecting member 8 connects the proximal end of the flexible tube 5 to the rear portion of the engine 2 so as to be rotatable about the axis X. This connecting member 8 ′ has a cylindrical portion 80 ′ and a cap portion 81 ′ similar to the second member 71 of the movable connecting mechanism 7, so that the proximal end of the flexible tube 5 can be rotated about the axis X. It is linked to. The transmission shaft 6 inserted through the flexible tube 5 is connected to the output shaft of the engine 2 so as to be rotatable through the inside of the connecting member 8. Thereby, when the transmission shaft 6 rotates, the flexible tube 5 is easily twisted and deformed. At this time, the cylindrical portion 80 ′ of the connecting member 8 together with the cylindrical portion 710 of the second member 71 in the movable connecting mechanism 7 is rotated, so that the torsional deformation of the flexible tube 5 is alleviated, and as a result, the entire flexible tube 5 is Bending deformation is also alleviated. In addition, when the rear portion of the engine 2 is swung around the rotation axis P, the torsional deformation is alleviated to some extent together with the bending deformation of the flexible tube 5.

  Next, the operation of the backpack type power working machine A2 will be described.

  In the shoulder-type power working machine A2 of this embodiment, in addition to the movable connecting mechanism 7 rotating around the rotation axis S as in the first embodiment described above, a part thereof (the second member 71 of the second member 71). The cylindrical portion 710) rotates about the axis T.

  For example, when the operation tube 3 is rotated, the first member 70 fixed to the operation tube 3 is also integrally rotated, and the bracket portion 711 of the second member 71 connected to the first member 70 is It turns around the center axis of its rotation.

  At this time, the bracket portion 711 can rotate about the rotation axis S with respect to the first member 70, but is not rotated so much and takes a posture generally along the longitudinal direction of the operation tube 3. Therefore, the bracket portion 711 rotates around an axis along the axis T almost along with the rotation of the operation tube 3.

  On the other hand, the distal end of the flexible tube 5 is connected to the bracket portion 711 via a cylindrical portion 710 that can rotate about the axis T. The flexible tube 5 is relatively positioned with respect to the bracket portion 711. It is easy to roll. That is, when the operation tube 3 is pivoted, the bracket portion 711 and the flexible tube 5 are likely to be displaced from each other around the axis T. Therefore, the distal end of the flexible tube 5 is greatly moved by the movement of the bracket portion 711. There is no twist.

  Further, in the shoulder-type power working machine A2 of the present embodiment, the cylindrical portion 80 'of the connecting member 8 is also rotatable about the axis X. Therefore, this cylinder part 80 ′ exhibits the same action as the cylinder part 710 of the movable connecting mechanism 7, and the proximal end of the flexible tube 5 connected to the cylinder part 80 ′ is largely pivoted and twisted. There is no.

  Since the flexible tube 5 is not easily twisted by the movable connecting mechanism 7 and the connecting member 8 and resistance due to the torsional deformation is not easily transmitted to the operation tube 3, the operator swings the operation tube 3 up, down, left and right. In addition, the operation tube 3 can be easily rotated according to the work situation.

  Further, the flexible tube 5 is caused to generate a frictional force in the direction around the shaft when the transmission shaft 6 that rotates on the inner peripheral surface of the flexible tube 5 comes into contact with the flexible tube 5, and tries to twist and deform by this frictional force. This torsional deformation becomes more prominent as the speed of rotation of the transmission shaft 6 increases. Since the torsional deformation of the flexible tube 5 due to such friction is difficult to be transmitted through the movable connecting mechanism 7 and the connecting member 8, the operator can resist the operation tube 3 and the engine 2 due to the torsional deformation of the flexible tube 5. You can work without feeling so much.

  For example, when lifting the operation tube 3 as shown in FIG. 13, the operator can lift the operation tube 3 by holding the side grip 30 ′ with the right hand in a reverse hand shape and lifting the loop handle 33 with the left hand. . When performing the brushing work on the slope in this way, the operator moves the operation tube 3 while moving forward while standing at a position where the slope is viewed from the side, for example. The right hand may have an external fitting grip 30.

  At this time, the operator moves the operation tube 3 up and down along the inclined surface while keeping the rotary blade B substantially parallel to the inclined surface. At that time, the operation tube 3 is pivoted to some extent by tilting the rotary blade B from a horizontal posture so as to follow the inclined surface. However, as described above, even if the operation tube 3 pivots, the flexible tube 5 does not rotate. Since it is difficult to twist and deform, the operator can easily operate the operation tube 3 without feeling not only the bending deformation of the flexible tube 5 but also the resistance due to the torsional deformation.

  Further, when the rotary blade B is arranged along the flat ground as shown in FIG. 14, the operator holds the side grip 30 ′ and the loop handle 33 in a state where the elbow portion of the right arm is pressed against the elbow receiving member 32. The operation tube 3 can be held in such a posture that the tip portion 3A of the operation tube 3 is held down and lowered. In this way, even when the mowing work is performed on the flat ground, the operator may rotate the operation tube 3 in order to cut the vegetation efficiently. Even in this case, since the flexible tube 5 is difficult to twist and deform, the operator can easily operate the operation tube 3 without feeling much resistance due to the twist deformation of the flexible tube 5.

  On the other hand, during the operation as described above, the torsional deformation of the flexible tube 5 becomes excessive, and the force due to the torsional deformation may be transmitted to the operation tube 3 as an external force for rotating the operation tube 3. Even in this case, the operator holds the side grip 30 'protruding in the lateral direction of the operation tube 3, and effectively controls the external force by the moment of the force applied to the side grip 30'. Therefore, unnecessary rotation of the operation tube 3 can be reliably suppressed.

  Therefore, according to the shoulder type power working machine A2, in addition to the effects of the first embodiment described above, it is possible to exert an effect that the operation tube 3 can be operated easily even if the operation tube 3 is rotated.

  15 and 16 show a third embodiment of a backpack type power working machine. The shoulder-type power working machine A3 of the present embodiment is such that the cap portion 717 of the second member 71 of the movable connecting mechanism 7 is fixed to the rear end of the bracket portion 711 by screwing, and the other configurations are described above. This is the same as that according to the second embodiment. In FIGS. 15 and 16, a cover that covers the connecting portion is omitted. According to such a screw-in type cap part 717, the gap with the bracket part 711 can be easily adjusted by adjusting the screwing amount. For example, the end part 710 </ b> A can be easily moved to the bracket part 711. Axial rotation around the axis T of the cylindrical portion 710 can be made smoother.

  FIGS. 17-21 has shown 4th Embodiment of the shoulder-type power working machine. The shoulder-type power working machine A4 of this embodiment does not include an external fitting grip, but includes a side grip 30 'and an operation unit 31 on a support arm 320. This side grip 30 ′ is also used when lifting the distal end portion 3 </ b> A of the operation tube 3. Other configurations are the same as those according to the second embodiment described above.

  As shown in FIG. 17, the side grip 30 ′ extends in the horizontal lateral direction on the same side as the side on which the elbow support member 32 is disposed with respect to the support arm 320 and is directly attached to the support arm 320. . As shown in FIGS. 18 and 19, the side grip 30 ′ is provided at a position closer to the rotation axis S of the movable coupling mechanism 7. Specifically, the attachment position of the side grip 30 ′ according to the present embodiment is a position retracted from the rotation axis S to the rear side by about 2 to 3 cm, for example, along the axial direction of the operation tube 3. When the side grip 30 ′ is positioned in the vicinity of the rotation axis S of the movable coupling mechanism 7 in this manner, the resistance felt by the hand holding the side grip 30 ′ is reduced, and the movable coupling mechanism 7 smoothly moves according to the movement of the hand. It is made to work. The operating portion 31 is located on the front side in the vicinity of the proximal end portion of the side grip 30 ′ and is directly attached to the support arm 320. Since the accelerator lever 311 of the operation unit 31 also remains in the position moved by, for example, frictional locking, the operator does not always have to operate the accelerator lever 311. Since the movable connecting mechanism 7 and the connecting member 8 of this embodiment have the same configuration as that of the second embodiment, the operator can easily rotate the operation tube 3. In addition, the operation tube 3 can be operated lightly without causing much resistance to the engine 2 due to torsional deformation of the flexible tube 5.

  In particular, according to the present embodiment, when the operation tube 3 is lifted as shown in FIG. 20, for example, the operator pushes the right hand having the side grip 30 ′ slightly forward as the loop handle 33 is pulled up with the left hand. . At that time, since the position of the right hand is in the vicinity of the rotation axis S of the movable coupling mechanism 7, the operator feels much resistance due to bending deformation or torsional deformation of the flexible tube 5 as compared with the case of having a position farther than that. Therefore, the operation tube 3 can be operated smoothly.

  Further, as shown in FIG. 21, even when the operator has the side grip 30 ′ with the tip 3 </ b> A of the operation tube 3 lowered and pressing the elbow portion of the right arm against the elbow support member 32, The resistance of the flexible tube 5 due to bending deformation or twisting deformation is not so much felt on the right hand, and the operation tube 3 can be operated smoothly. As a result, when the operation tube 3 is swung to the left or right or pivoted, the operator can operate the operation tube 3 with a lighter force without placing much burden on the right hand and the elbow portion of the right arm. it can.

  Therefore, according to the shoulder type power working machine A4, in addition to the effects of the first and second embodiments described above, the operation tube 3 can be operated lightly without feeling more resistance due to deformation of the flexible tube 5. The effect that it can be performed can be exhibited.

  FIG. 22 shows a fifth embodiment of a backpack type power working machine. The backpack type power working machine A5 of the present embodiment is different from the backpack type power working machine A1 shown in FIG. This shoulder-type power working machine A5 is suitable for trimming branches and leaves in a relatively high tree, for example, and includes a hedge trimmer H as a working body having a reciprocating shear blade B '.

  The hedge trimmer H includes left and right reciprocating shear blades B ′ having comb-like blades protruding downward, and a drive unit 9 that relatively reciprocates these reciprocating shear blades B ′ back and forth. The drive unit 9 includes a bevel gear mechanism (not shown) and a reciprocating mechanism connected to a base end portion of the reciprocating shear blade B ′. The reciprocating shear blade B ′ is connected to the bevel mechanism and the reciprocating mechanism. Are connected to the transmission shaft 6. According to the shoulder-type power working machine A5 provided with such a hedge trimmer H, for example, when cutting branches and leaves at a position higher than the height of the worker, the worker can carry the shoulder frame 1 as in the above-described embodiment. The grip 30 may be held with the right hand and the loop handle 33 may be held with the left hand so as to be raised higher than the holding position of the right hand. As a result, the hedge trimmer H provided at the tip of the operation tube 3 is lifted upward and the reciprocating shearing blade B 'can be disposed at a high position of the tree to be worked. In the reciprocating shear blade B ′, the rotational output of the engine 2 is transmitted to a transmission shaft (not shown) according to the operation of the accelerator lever 311, and the transmission shaft rotates to activate a bevel gear mechanism or a reciprocating mechanism (not shown). To be reciprocated relative to each other. In such a state, the operator can perform an operation so as to apply a downward force to the distal end portion of the operation tube 3, and by doing so, the branches and leaves can be trimmed. Thereby, the operator can easily perform trimming with the reciprocating shearing blade B 'even on the branches and leaves at a high position of the tree.

  Therefore, even with the shoulder-type power working machine A5, the operation tube 3 is easily lifted higher than the waist position of the operator, and even if the operation tube 3 is swung, the flexible tube 5 can be bent and deformed as much as possible. The transmission shaft 6 can be kept small, and the transmission shaft 6 is not brought into contact with the flexible tube 5 for a long time. Therefore, the operator can perform a light operation while lifting the operation tube 3 with respect to a high position of the tree, and can perform a work comfortably while suppressing unreasonable heat generation of the flexible tube 5.

  The scope of the present invention is not limited to the above-described embodiments, and all modifications within the scope of the matters described in each claim are included in the scope of the present invention.

  For example, the movable coupling mechanism is not limited to the one described in the above embodiment in which it rotates around the horizontal axis of the operation tube, and for example, a universal joint or a ball joint may be applied.

  For example, a universal joint or a ball joint may be applied to the connecting member connected to the rear part of the engine.

  For example, a hedge trimmer having a reciprocating shear blade may be applied to the shoulder-type power working machine of the second to fourth embodiments.

A1-A5 Backpack-type power work machine 1 Backpack frame 2 Engine (power source)
DESCRIPTION OF SYMBOLS 3 Operation pipe | tube 3A Tip part 30 External fitting grip 30 'Side grip 301 Extension part 31 Operation part 32 Elbow receiving member 320 Support arm 33 Loop handle 40 Fixed member B Rotary blade (working body)
H hedge trimmer (work body)
B 'reciprocating shear blade 5 flexible tube 6 transmission shaft 7 movable connecting mechanism 8 connecting member S rotating shaft

Claims (17)

An operating tube extending in a longitudinal shape, a working body supported at the distal end of the operating tube, a power source supported by a backpack frame, one end connected to the power source, and the other end at the proximal end of the operating tube The connected flexible tube and the flexible tube or the operation tube are inserted into the working body to transmit the rotational output of the power source to the working body and operate the at least the flexible tube. The part up to the operation tube is a shoulder-type power working machine equipped with a transmission shaft having flexibility,
A grip provided on the proximal end of the operation tube and gripped by an operator's hand;
A movable connection mechanism for connecting the other end of the flexible tube to the proximal end of the operation tube so as to be rotatable around a horizontal rotation axis within a predetermined angle range;
A handle provided at an intermediate portion of the operation tube and gripped to hang the operation tube by an operator's hand;
A backpack-type power working machine characterized by comprising:   2. The shoulder-type power working machine according to claim 1, wherein one end of the flexible tube is connected to the power source via a connecting member that can rotate in the axial direction of the transmission shaft.   The shoulder-type power working machine according to claim 2, wherein the other end of the flexible tube is also connected to the movable connecting mechanism so as to be rotatable.   The shoulder-type power working machine according to any one of claims 1 to 3, wherein the grip is an external fitting grip provided so as to surround the operation tube.   The grip includes two types of an external fitting grip provided to surround the operation tube and a side grip provided near the front end of the external fitting grip so as to extend to one side of the operation tube in the lateral direction. The backpack type power working machine according to any one of claims 1 to 3.   The shoulder-type power working machine according to claim 4 or 5, wherein the outer fitting grip is provided with an extending portion extending downward of the movable coupling mechanism.   A support arm extending upward and rearward of the operation tube is also provided at the proximal end of the operation tube, and a forearm of an operator holding the grip is provided below the support arm at the distal end. The shoulder-type power working machine according to any one of claims 1 to 6, wherein an elbow receiving member received from the back is supported.   A support arm that extends upward and rearward of the operation tube is also provided at the proximal end of the operation tube, and the grip is provided on the support arm so as to extend to one side in the lateral direction of the operation tube. The shoulder-type power working machine according to any one of claims 1 to 3, which is a lateral grip.   The shoulder-type power working machine according to claim 8, wherein the side grip is provided on a rear side with respect to a rotation shaft of the movable coupling mechanism.   The shoulder-type power working machine according to claim 8 or 9, wherein an elbow support member that receives a forearm of an operator holding the side grip from below is supported at a tip of the support arm.   The shoulder-type power working machine according to any one of claims 1 to 10, wherein an operation unit for controlling a rotational output of the power source is provided in the vicinity of the grip.   The shoulder-type power working machine according to any one of claims 1 to 11, wherein the handle is a loop handle having a loop shape above the operation pipe.   The backrest-type power working machine according to any one of claims 1 to 12, wherein the power source is supported so as to be rotatable around a rotation shaft extending in a vertical direction with respect to the backrest frame.   The shoulder-type power working machine according to any one of claims 1 to 13, wherein the working body is a rotary blade for brush cutting.   The rotary blade is supported by the operation tube so as to be rotatable about a rotation axis extending in a direction intersecting the rotation axis of the movable coupling mechanism in the axial direction of the operation tube. Item 15. The shoulder-type power work machine according to Item 14.   The shoulder-type power working machine according to claim 15, wherein the rotation shaft is substantially orthogonal to the rotation axis of the movable coupling mechanism in the axial direction of the operation tube.   The shoulder-type power working machine according to any one of claims 1 to 13, wherein the working body is a hedge trimmer having a reciprocating shear blade.

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