JP6228812B2 - Portable engine work machine - Google Patents

Description

  The present invention relates to a portable engine working machine such as a brush cutter, a chain saw, or a power blower that is driven by power of an engine.

  Conventionally, this type of portable engine work machine includes a working unit, an engine that drives the working unit, a throttle cable connected to the throttle valve of the engine, and a direction that opens the throttle valve by pulling the throttle cable. A throttle lever that operates and a valve opening adjustment mechanism that adjusts the opening amount of the throttle valve by adjusting the pulling amount of the throttle cable that is pulled by the operation of the throttle lever of a predetermined operation amount are known. (For example, refer to Patent Document 1). In this portable engine working machine, it is possible to arbitrarily set the engine output in the operation of the throttle lever of a predetermined operation amount by the valve opening adjustment mechanism.

  The valve opening adjusting mechanism adjusts the throttle lever operation amount at which the throttle lever operation force starts to act in the direction of pulling the throttle cable. Is adjusted. That is, in the portable engine work machine, when the throttle cable pulling amount is set to be small in the operation of the throttle lever having a predetermined operation amount, the play amount of the throttle lever is increased. Further, in the portable engine work machine, when the throttle cable pulling amount is set large in the operation of the throttle lever of a predetermined operation amount, the play amount of the valve opening lever is reduced.

Japanese Patent No. 4490322

  In the portable engine work machine, the play amount of the throttle lever changes with the change of the pull amount of the throttle cable in the operation of the throttle lever of a predetermined operation amount. For this reason, in the portable engine work machine, the amount of operation of the throttle lever where the engine output starts to change from the idle state differs depending on the setting state of the valve opening adjustment mechanism. May be affected.

  The object of the present invention is to improve the operability and safety of the user by making the operation amount of the throttle lever constant so that the engine output starts to change from the idle state regardless of the setting state of the valve opening adjustment mechanism. An object of the present invention is to provide a portable engine working machine that can be improved.

In order to achieve the above object, the present invention provides a working unit, an engine that drives the working unit, a throttle cable connected to a throttle valve of the engine, and pulls the throttle cable to open the throttle valve. A throttle lever that performs an operation in a direction to perform, a valve opening adjustment mechanism that adjusts an opening amount of the throttle valve by adjusting a tensile amount of the throttle cable that is pulled by an operation of the throttle lever of a predetermined operation amount; The valve opening adjustment mechanism is rotatably supported in the vicinity of the throttle lever, and has a cable connection portion to which the throttle cable is connected and an operation input portion to which an operation force of the throttle lever acts. Pulling the throttle cable by operating the throttle lever By changing the ratio of the distance between the center of rotation of the tension link and the cable connecting portion and the distance between the center of rotation of the tension link and the operation input unit. The amount of operation of the throttle lever is adjusted by adjusting the amount of operation of the throttle lever, and the amount of operation of the throttle lever starts to act in the direction in which the operating force of the throttle lever pulls the throttle cable. It is constant regardless of the amount of tension of the throttle cable adjusted by the valve opening adjustment mechanism .

  As a result, even when the amount of throttle cable tension that is pulled by operating the throttle lever of a predetermined operation amount is changed by the valve opening adjustment mechanism, the operating force of the throttle lever starts to act in the direction of pulling the throttle cable. The operation amount of the throttle lever is constant.

  According to the present invention, since the operation amount of the throttle lever that starts to act in the direction in which the throttle lever operating force pulls the throttle cable can be made constant, the operation of the throttle lever where the engine output starts to change from the idle state The amount becomes constant, and the operability and safety of the user can be improved.

It is a perspective view of a brush cutter provided with the output adjustment device which shows one Embodiment of this invention. It is a perspective view of an output adjustment device. It is a side view of the output adjustment apparatus which removed some housings. It is side surface sectional drawing of an output adjustment apparatus. It is AA 'sectional drawing of FIG. It is the schematic of the structure which changes the tension | tensile_strength amount of a throttle cable with respect to operation of a predetermined amount of throttle levers. It is a figure which shows the operating method of an output adjustment apparatus. It is a figure which shows the output adjustment method of an engine. It is a figure which shows the output adjustment method of an engine. It is a figure which shows the output adjustment method of an engine. It is a side view of the output adjustment apparatus which removed some housings which show the other example of this invention.

  1 to 10 show an embodiment of the present invention. The following embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications or changes can be made without departing from the scope of the invention. .

  In this embodiment, an engine-driven brush cutter will be described as an example of the portable engine working machine of the present invention.

  As shown in FIG. 1, the brush cutter 1 includes an operation rod 2 extending in the front-rear direction, an engine 3 as a drive source connected to the rear end side of the operation rod 2, and a gear head 4 on the front end side of the operation rod 2. And a cutting blade 5 as a disk-like working portion attached rotatably through the.

  The operation rod 2 has a drive shaft (not shown) rotatably provided therein. The engine 3 is connected to the rear end side of the drive shaft. A gear head 4 is connected to the front end side of the drive shaft.

  Further, a handle 6 that is held by the user with one hand (for example, the left hand) when the user operates the brush cutter 1 is provided slightly behind the central portion of the operation rod 2. The handle 6 is an annular member that protrudes above and to the left and right of the operating rod 2. The handle 6 is inclined obliquely rearward so that the upper side faces rearward.

  A grip 7 that is held by the user with the other hand (for example, the right hand) when the user operates the brush cutter 1 is provided at a portion located between the engine 3 and the handle 6 of the operating rod 2. ing. The grip 7 is a cylindrical member that covers the outer periphery of the operation rod 2.

  An output adjusting device 100 for adjusting the output of the engine 3 while the user holds the grip 7 with the other hand is provided at a portion of the operating rod 2 positioned in front of the grip 7. The output adjusting device 100 adjusts the opening of a throttle valve (not shown) provided in the engine 3 in order to adjust the output of the engine 3.

  As shown in FIGS. 2 to 5, the output adjusting device 100 includes a housing 101 provided in a portion located in front of the grip 7 of the operating rod 2, a throttle cable 110 connected to a throttle valve of the engine 3, A throttle lever 120 for performing the operation of pulling the throttle cable 110 and a valve opening for adjusting the opening of the throttle valve by adjusting the pull amount of the throttle cable 110 pulled by the operation of the throttle lever 120 of a predetermined operation amount. Degree adjusting mechanism 130.

  The throttle cable 110 has one end connected to the throttle valve and the other end connected to a later-described tension link of the valve opening adjustment mechanism 130. The throttle cable 110 is movably provided in the outer tube 111 extending along the operation rod 2 between the throttle valve and the housing 101. The throttle cable 110 extends to a position where the other end is separated from the end of the outer tube 111, and the other end can be moved in the radial direction of the outer tube 111.

  The throttle lever 120 is formed of a member that extends in the front-rear direction below the operation rod 2. On the front end side of the throttle lever 120, a support portion 120a that is rotatably supported by the housing 101 via a support shaft 121 is provided. The throttle lever 120 is formed so as to extend rearward from the support portion 120a below the grip 7, and is provided with an operation portion 120b for the user to operate with the other hand. The operation unit 120b is formed to extend along the lower side of the grip 7 when the throttle lever 120 is operated with the operation unit 120b facing upward as much as possible. As shown in FIGS. 4 and 5, the throttle lever 120 is formed to extend upward from the support portion 120a, and the force that operated the user's operation portion 120b is used as a tension link described later of the valve opening adjustment mechanism 130. There is an operating force transmission part 120c for transmitting to the. The operating force transmission portion 120c is provided with an engagement pin 120d that engages with a tension link described later so as to extend in the width direction. As shown in FIG. 4, the throttle lever 120 is biased by a compression spring 120 e in a direction in which the operation portion 120 b is separated from the grip 7.

  The valve opening adjustment mechanism 130 is connected to a tension link 131 that pulls the throttle cable 110 in conjunction with the operation of the throttle lever 120, and a throttle link 131 that is connected to the tension link 131 and that is operated by operating the throttle lever 120 with a predetermined operation amount. A tension amount adjusting lever 132 for adjusting the tension amount of the cable 110.

  The tension link 131 is provided with a cable connection portion 131 a to which the other end of the throttle cable 110 is connected at one end, and a support portion 131 b that is rotatably supported by the tension adjustment lever 132 via a support shaft 133. It is provided at the other end. Further, the pulling link 131 is provided with a contact surface 131c as an operation input portion with which the engagement pin 120d of the throttle lever 120 abuts between the cable connection portion 131a and the support portion 131b. The contact surface 131c is a portion located on the front side of the side wall of the groove 131d provided between the cable connection portion 131a and the support portion 131b.

  The tension link 131 rotates around the support portion 131b by bringing the engagement pin 120d into contact with the contact surface 131c by operating the throttle lever 120. The tension link 131 pulls the throttle cable 110 by rotating in the direction in which the cable connection portion 131a is moved forward around the support portion 131b.

  The tension amount adjusting lever 132 is rotatably supported on the housing 101 via a support shaft 134 so that the upper end side is movable in the front-rear direction. At the upper end of the tension adjustment lever 132, an operation portion 132a for performing an operation of moving the tension adjustment lever 132 in the front-rear direction with the thumb of the hand holding the grip 7 is provided. On the lower end side of the tension adjustment lever 132, there is provided a connecting portion 132b that extends forward and a support portion 131b of the tension link 131 is rotatably connected via a support shaft 133.

  The tension adjustment lever 132 can hold the posture at an arbitrary position within a range in which the operation unit 132a can be operated in the front-rear direction. The pull amount adjusting lever 132 can maintain a state in which the operation portion 132a is set at an arbitrary position in the front-rear direction when performing an operation of pulling the throttle cable 110 by the throttle lever 120.

  When the operation amount 132a is moved to the front side of the tension amount adjusting lever 132, the connecting portion 132b is moved downward. When the connecting portion 132b moves downward, the tensile link 131 connected to the connecting portion 132b also moves downward, and the distance between the support portion 131b of the tensile link 131 and the engagement pin 120d of the throttle lever 120 increases.

  In addition, when the operation amount 132a is moved rearward, the tension adjustment lever 132 moves the connecting portion 132b upward. When the connecting portion 132b moves upward, the tensile link 131 connected to the connecting portion 132b also moves upward, and the distance between the support portion 131b of the tensile link 131 and the engagement pin 120d of the throttle lever 120 becomes small.

  The tension adjustment lever 132 moves the tension link 131 by operating the operation portion 132a, so that the support portion 131b that is the rotation center of the tension link 131 and the engagement pin 120d of the throttle lever 120 on the contact surface 131c abut. It is possible to adjust the ratio of the distance D1 between the parts (operation input units) and the distance D2 between the support part 131b and the cable connection part 131a.

  That is, in the state of FIG. 6 (b), the portion where the engagement pin 120d of the throttle lever 120 of the support portion 131b and the contact surface 131c contacts the distance D2 between the support portion 131b and the cable connection portion 131a. When the ratio of the distance D1 to the (operation input unit) is decreased, the pull amount P of the throttle cable 110 is increased with respect to the throttle lever 120 having a predetermined operation amount M as shown in FIG.

  Further, in the state shown in FIG. 6B, a portion where the engagement pin 120d of the throttle lever 120 of the support portion 131b and the contact surface 131c abuts against the distance D2 between the support portion 131b and the cable connection portion 131a. When the ratio of the distance D1 to the (operation input unit) is increased, the tensile amount P of the throttle cable 110 is decreased with respect to the throttle lever 120 having a predetermined operation amount M, as shown in FIG.

  In the present embodiment, the cable connection portion 131a side of the contact surface 131c of the tension link 131 is formed so as to protrude forward. Thereby, with respect to the distance D2 between the support portion 131b and the cable connection portion 131a, the support portion 131b and the portion (operation input portion) where the engagement pin 120d of the throttle lever 120 of the contact surface 131c contacts. When the ratio of the distance D1 is increased to the maximum, play occurs in the operation of pulling the throttle cable 110 of the throttle lever 120, and the pull amount P decreases.

  In the brush cutter 1 as a portable engine working machine configured as described above, when the engine 3 is started and the throttle lever 120 is not operated, regardless of the operating position of the operating portion 132a of the tension adjustment lever 132. The engine 3 is in an idle operation state.

  When working with the brush cutter 1 while the engine 3 is idling, the user grips the handle 6 with one hand (for example, the left hand) and grips with the other hand (for example, the right hand). Grip 7 At this time, when the user grips the grip 7 with the other hand, as shown in FIG. 7, the user operates the operation portion 120 b of the throttle lever 120 to the grip 7 side as much as possible. The operation unit 120b is held together. As shown in FIG. 8, the brush cutter 1 performs an operation with the operation amount of the throttle lever 120 that is operated when the user holds the grip 7 together with the grip 7.

  The brush cutter 1 can adjust the output of the engine 3 in a state where the user grips the grip 7 and the operation part 120b of the throttle lever 120 at the same time (FIG. 8). The output of the engine 3 is adjusted by moving the operation part 132a of the tension adjustment lever 132 in the front-rear direction with the thumb of the hand holding the grip 7 and the operation part 120b of the throttle lever 120.

  When the output of the engine 3 is increased from the position of the center part in the front-rear direction of the range in which the operation unit 132a is movable (the state shown in FIG. 6B), as shown by the arrow R in FIG. Move backwards. When the operation portion 132a is moved rearward, the tension link 131 moves upward, and the distance between the support portion 131b that is the rotation center of the tension link 131 and the engagement pin 120d that is in contact with the contact surface 131c is reduced. . As a result, as shown in FIG. 9, the engagement pin 120d of the throttle lever 120 of the support portion 131b and the contact surface 131c abuts against the distance D2 between the support portion 131b and the cable connection portion 131a ( The ratio of the distance D1 to the operation input unit) is reduced, and the tension amount P of the throttle cable 110 with respect to the throttle lever 120 having a predetermined operation amount M is increased (the state shown in FIG. 6C). When the pulling amount P of the throttle cable 110 increases, the throttle valve opening increases, so the output of the engine 3 increases.

  Further, when the output of the engine 3 is reduced from the position of the center part in the front-rear direction of the range in which the operation part 132a is movable (state of FIG. 6B), as shown by the arrow F in FIG. The part 132a is moved forward. When the operation portion 132a is moved forward, the tension link 131 moves downward, and the distance between the support portion 131b that is the rotation center of the tension link 131 and the engagement pin 120d that is in contact with the contact surface 131c increases. . As a result, as shown in FIG. 10, with respect to the distance D2 between the support portion 131b and the cable connection portion 131a, a portion where the engagement pin 120d of the throttle lever 120 of the support portion 131b and the contact surface 131c abuts ( The ratio of the distance D1 to the operation input unit) increases, and the pulling amount P of the throttle cable 110 with respect to the throttle lever 120 having a predetermined operation amount M decreases (state shown in FIG. 6A). When the pulling amount P of the throttle cable 110 decreases, the opening of the throttle valve decreases, so the output of the engine 3 decreases.

  The valve opening degree adjusting mechanism 130 includes a portion (operation input portion) where the engagement pin 120d of the throttle lever 120 of the contact portion 131b and the contact surface 131c contacts the distance D2 between the support portion 131b and the cable connection portion 131a. By changing the ratio of the distance D1 between the two, the pulling amount P of the throttle cable 110 with respect to the throttle lever 120 with a predetermined operation amount M is changed. Therefore, the operation amount of the throttle lever 120 at which the operation force of the throttle lever 120 starts to act in the direction of pulling the throttle cable 110 is constant regardless of the setting position of the tension adjustment lever 132.

As described above, in the portable engine working machine of the present embodiment, the operating force of the throttle lever 120 and the cable connecting portion 131a to which the throttle cable 110 is connected are rotatably supported in the vicinity of the front end portion of the throttle lever 120. And a tension link 131 that pulls the throttle cable 110 by operating the throttle lever 120, and a distance D2 between the rotation center of the tension link 131 and the cable connecting portion 131a. By changing the ratio of the distance D1 between the center of rotation of the tension link 131 and the portion of the abutment surface 131c where the engagement pin 120d abuts, the tension is applied by operating the throttle lever 120 with a predetermined operation amount M. The tension amount P of the throttle cable 110 to be adjusted is adjusted.
As a result, the operation amount of the throttle lever 120 at which the operating force of the throttle lever 120 starts to act in the direction of pulling the throttle cable 110 can be made constant, so that the output of the engine 3 starts to change from the idle state. Therefore, the operability and safety of the user can be improved.

In addition, the valve opening adjusting mechanism 130 moves the support 131b serving as the center of rotation of the tension link 131, so that the distance D2 between the center of rotation of the tension link 131 and the cable connecting portion 131a and the tension link 131 are increased. The ratio of the distance D1 between the center of rotation and the portion of the contact surface 131c with which the engagement pin 120d contacts is changed.
As a result, the tensile amount P of the throttle cable 110 that is pulled by the operation of the throttle lever 120 having a predetermined operation amount M can be adjusted with a simple structure, so that the manufacturing cost can be reduced.

Further, the valve opening adjustment mechanism 130 has a tension adjustment lever 132 that can be operated to move the rotation center of the tension link 131.
As a result, it is possible to adjust the tension amount P of the throttle cable 110 that is pulled by the operation of the throttle lever 120 having the predetermined operation amount M while the user who is using the brush cutter 1 performs the operation. Can be improved.

  In the above-described embodiment, the brush cutter 1 according to the present invention is shown as an example of the portable engine working machine. However, the present invention is not limited to this. The present invention can also be applied to portable engine working machines such as chainsaws and power blowers.

In the above-described embodiment, the cable connection portion 131a side of the contact surface 131c of the tension link 131 is formed so as to protrude forward. However, the present invention is not limited to this.
As shown in FIG. 11, the contact surface 131e is formed in a flat shape between the cable connection portion 131a and the support portion 131b so that play does not occur in the operation of pulling the throttle cable 110 of the throttle lever 120. Good. In this case, the relationship between the amount of operation of the throttle lever 120 and the amount of tension of the throttle cable 110 is expressed as the distance between the support portion 131b and the engagement pin 120d with respect to the distance D2 between the support portion 131b and the cable connection portion 131a. It is possible to relate more accurately by the ratio of D1.

  Moreover, in the said embodiment, by moving the support part 131b of the tension link 131, the distance D2 between the rotation center of the tension link 131 and the cable connection part 131a, the rotation center of the tension link 131, and the contact surface 131c. Although the ratio of the distance D1 to the portion with which the engagement pin 120d abuts is changed is shown, the present invention is not limited to this. The ratio of the distance D2 between the rotation center of the tension link 131 and the cable connecting portion 131a to the distance D1 between the rotation center of the tension link 131 and the portion where the engagement pin 120d of the contact surface 131c abuts. If it can be changed, for example, the support portion 131b as the rotation center of the tension link 131 is rotatably supported by the housing 101, and the rotation center of the throttle lever 120 can be moved. The ratio between the distance D2 between the cable connecting portion 131a and the distance D1 between the rotation center of the tension link 131 and the portion where the engagement pin 120d of the contact surface 131c abuts may be changed. .

  Moreover, in the said embodiment, the brush cutter 1 which has the cyclic | annular handle | steering-wheel 6 which protrudes from the operating rod 2 to upper direction and both right and left sides, and the grip 7 provided between the engine 3 of the operating rod 2 and the handle 6 is provided. Although shown, it is not limited to this. For example, the present invention can also be applied to a brush cutter having a handle that is curved in a U-shape projecting upward and from the left and right sides from the operating rod, and grips provided at both ends of the handle.

  DESCRIPTION OF SYMBOLS 1 ... Brush cutter, 3 ... Engine, 5 ... Cutting blade, 100 ... Output adjusting device, 110 ... Throttle cable, 120 ... Throttle lever, 130 ... Valve opening adjustment mechanism, 131 ... Tension link, 131a ... Cable connection part, 131b ... support part, 131c ... contact surface, 132 ... tension adjustment lever.

Claims (3)

A working section;
An engine for driving the working unit;
A throttle cable connected to the throttle valve of the engine;
A throttle lever that pulls the throttle cable and operates in a direction to open the throttle valve;
A valve opening adjustment mechanism that adjusts an opening amount of the throttle valve by adjusting a pulling amount of the throttle cable that is pulled by an operation of the throttle lever of a predetermined operation amount;
The valve opening adjustment mechanism is
A cable connecting portion that is rotatably supported in the vicinity of the throttle lever and to which the throttle cable is connected, and an operation input portion on which an operating force of the throttle lever acts, and the throttle cable is operated by operating the throttle lever. It has a tension link that performs the tensioning action,
By changing the ratio of the distance between the center of rotation of the tension link and the cable connection portion and the distance between the center of rotation of the tension link and the operation input unit, the predetermined operation amount is changed. Adjust the amount of tension of the throttle cable that is pulled by operating the throttle lever ,
The operation amount of the throttle lever which starts to act in the direction in which the operation force of the throttle lever pulls the throttle cable is constant regardless of the pull amount of the throttle cable adjusted by the valve opening adjustment mechanism. Features a portable engine work machine. The valve opening adjustment mechanism moves the rotation center of the tension link, thereby moving the distance between the rotation center of the tension link and the cable connection portion, the rotation center of the tension link, and the operation input unit. The portable engine working machine according to claim 1, wherein a ratio of the distance between the two is changed. The portable engine working machine according to claim 2, wherein the valve opening adjustment mechanism has a tension adjustment lever that can be operated to move the rotation center of the tension link.

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