JP3993433B2 - Cleaning structure of choke valve control device in power working machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention attaches a cooling fan to the upper end of a crankshaft arranged in the vertical direction, and has an engine with a work implement connected to the lower end of the shaft and a cooling air intake facing the cooling fan, and has an upper surface of the engine. An engine cover that guides the cooling air taken from the cooling air intake by the cooling fan to the engine, a carburetor attached to one side of the engine, and a choke operating lever that opens and closes the choke valve of the carburetor, Choke valve control comprising a choke spring that urges the valve in the valve opening direction, and a slow return means that slowly controls the valve opening operation when the valve is opened from the fully closed position by the urging force of the choke spring. The present invention relates to a cleaning structure for a choke valve control device in a power working machine including the device.
[0002]
[Prior art]
In a power working machine, a cooling fan is attached to the upper end of a vertically arranged crankshaft, and an engine having a work implement connected to the lower end of the shaft and a cooling air intake facing the cooling fan are provided. For example, Japanese Patent Application Laid-Open No. 10-121982 is provided with an engine cover that covers the upper surface and guides the cooling air taken in from the cooling air intake by the cooling fan to the engine and a carburetor attached to one side of the engine. It is already known as disclosed in the publication.
[0003]
[Problems to be solved by the invention]
In such a power work machine, a choke operating lever that opens and closes the choke valve of the carburetor, a choke spring that biases the valve in the valve opening direction, and the valve opens from the fully closed position by the biasing force of the choke spring when, in the case of providing the choke valve control device comprising a gentle speed return means for controlling the opening operation slowly, during the operation of the work implement by the engine, the choke dust is found to rise up by work implement within the long-term It can be considered that it accumulates in each part of the valve control device and causes its malfunction.
[0004]
The present invention has been made in view of the above points, and attaches a cooling fan to the upper end of a vertically arranged crankshaft and opposes the cooling fan to an engine having a work implement connected to the lower end of the shaft. An engine cover that covers the upper surface of the engine with a cooling air intake that guides the cooling air taken from the cooling air intake by the cooling fan to the engine, a carburetor attached to one side of the engine, and The choke control lever that opens and closes the carburetor choke valve, the choke spring that urges the valve in the valve opening direction, and when the valve is opened from the fully closed position by the urging force of the choke spring, the valve opening operation is slow. In a power work machine equipped with a choke valve control device comprising a slow return means for controlling the choke valve, the choke valve control is performed using engine cooling air generated by a cooling fan. Clean the dust adhered to the device, and to prevent the malfunction of the device due to dust, and to provide a cleaning structure of the choke valve control device in the power working machine.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an engine in which a cooling fan is attached to the upper end of a crankshaft arranged in a vertical direction, and a work implement is connected to the lower end of the shaft, and cooling air intake facing the cooling fan. An engine cover for covering the upper surface of the engine with a mouth and guiding the cooling air taken from the cooling air intake by the cooling fan to the engine, a carburetor attached to one side of the engine, and a choke of the carburetor Choke operating lever that opens and closes the valve, choke spring that urges the valve in the valve opening direction, and a slow valve that slowly controls the valve opening operation when the valve is opened from the fully closed position by the urging force of the choke spring. A power working machine having a choke valve control device comprising quick return means, wherein the choke valve is disposed in a path of the cooling air from the cooling air intake to the engine. With arranging the control device, the choke valve control device, the first, characterized in that attached to the lower surface of the extended portion of the bracket fixed to the engine.
[0006]
According to the first feature, during operation of the engine, the cooling air drawn from the cooling air intake port of the engine cover by the cooling fan passes through the choke valve control device in the process of being pumped to the engine, Blow away dust adhering to the choke valve control device and clean it. Therefore, it is possible to avoid accumulation of dust that is raised by the work implement on the choke valve control device, to prevent its malfunction, and to cool the device and improve its durability. . Also, the choke valve control device, so attached to the lower surface of the extended portion of the bracket fixed to the engine, dust hardly adheres, the cleaning effect can be highly Mel.
[0007]
The working tool, the cooling fan, the slow return means, and the extended portion of the bracket are formed on the left side of the cutting blade 7, the cooling fan / flywheel 9, the damper 38 and the bracket 14 in the embodiment of the present invention to be described later. corresponding respectively to the extension portion was.
[0008]
In addition to the first feature, the second feature of the present invention is that the tip of the choke operating lever protrudes outward of the engine cover.
[0009]
According to the second feature, the choke operation lever can be easily opened and closed without being obstructed by the engine cover, and the lever can be visually checked. Accurate control of the choke valve can be easily performed.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.
[0011]
1 is a side view of a power lawn mower equipped with an engine equipped with a choke valve control device according to an embodiment of the present invention, FIG. 2 is a partially broken plan view of the engine, and FIG. 3 is a line 3-3 in FIG. 4 is a side view of the main part of FIG. 3, FIG. 5 is a view taken in the direction of arrow 5-5 in FIG. 4 (shows the operating state of the braking mechanism and the fully opened state of the choke valve), FIG. 7 is a sectional view taken along line -6 (however, the choke valve is shown in a fully closed state), FIG. 7 is a view taken in the direction of the arrow 7 and FIG. FIG. 9 is a diagram corresponding to FIG. 5, FIG. 9 is a diagram corresponding to FIG. 6, and FIG. 10 is a diagram corresponding to FIG. 6, illustrating a fully opened state of the choke valve. Is an enlarged plan view of the damper portion in FIG. 6, FIG. 12 is a sectional view taken along line 12-12 of FIG. 11, and FIG. 13 shows another embodiment of the present invention. It is a corresponding view.
[0012]
First, in FIG. 1, a walking type power lawn mower 1 as a power working machine has a housing 3 supported by a front wheel 2f and a rear wheel 2r. A vertical engine 4 having a crankshaft 5 disposed in the vertical direction is mounted on the upper surface of the housing 3, and a rotary cutting blade 7 attached to the lower end of the crankshaft 5 is disposed in the housing 3. A turf bag 8 is attached to the steering handle 6 coupled to the rear end of the housing 3 so as to store the turf cut by the cutting blade 7.
[0013]
2 to 5, a flywheel 9 that also serves as a cooling fan is fixed to the upper end of the crankshaft 5 of the engine 4, and an engine cover 10 that covers the upper surface of the engine 4 together with the flywheel 9 is fixed to the engine 4. The A recoil starter 11 that can drive the crankshaft 5 via a flywheel 9 and a starter cover 12 that covers the starter 11 are attached to the engine cover 10. The starter cover 12 is provided with a large number of cooling air intakes 13. When the flywheel 9, that is, the cooling fan is rotated, cooling air is drawn into the engine cover 10 from the cooling air intakes 13. The wind is guided to each part of the engine 4 by the engine cover 4. In FIG. 2, reference numeral 11 a is a rope pulling grip of the starter 11.
[0014]
A brake shoe 16 that cooperates with the cylindrical outer peripheral surface of the flywheel 9 is attached to a bracket 14 fixed to the engine 4 below the flywheel 9 via a pivot 17. The pivot 17 is disposed at a position closer to the inner side than the outer peripheral surface of the flywheel 9.
[0015]
The brake shoe 16 includes an arm 16a that extends between the bracket 14 and the flywheel 9 and extends outward from the outer peripheral surface of the flywheel 9, and a pressure contact portion that is bent from the tip of the arm 16a and faces the outer peripheral surface of the flywheel 9. 16b, and a lining 18 is bonded to the pressure contact portion 16b.
[0016]
Thus, the brake shoe 16 has a braking position A (see FIG. 5) where the lining 18 of the pressure contact portion 16b is pressed against the outer peripheral surface of the flywheel 9 and a braking release position B (see FIG. 5) which separates the lining 18 from the outer peripheral surface. 8 and 9) can be swung around the pivot axis 17. A brake spring 19 that biases the brake shoe 16 toward the braking position A is connected to the front end of the pressure contact portion 16 b of the brake shoe 16. The brake shoe 16, the flywheel 9 and the brake spring 19 constitute a braking mechanism 15 that stops the rotation of the crankshaft 5.
[0017]
Further, an operating arm 16c is integrally formed on the brake shoe 16, and an operation wire 21 which is pulled by a brake release lever 20 (see FIG. 1) pivotally supported by the steering handle 6 is provided at the tip of the operating arm 16c. Is connected and the operation wire 21 is pulled, the brake shoe 16 can be rotated to the brake release position B via the operating arm 16c.
[0018]
As shown in FIGS. 5 and 8, an engine kill switch 22 is installed on the upper surface of the bracket 14. When the brake shoe 16 reaches the braking position A, the engine kill switch 22 deactivates the engine ignition circuit (not shown) and stops the operation of the engine 4 in conjunction therewith.
[0019]
As shown in FIGS. 2 and 4, a carburetor 23 is attached to one side of the engine 4 and an exhaust muffler 26 is attached to the other side, and an air cleaner 24 is connected to an inlet of an intake passage 23 a of the carburetor 23. .
[0020]
The carburetor 23 is provided with a butterfly choke valve 25 that opens and closes the upstream portion of the intake passage 23 a with the valve shaft 25 a facing the vertical direction in the same manner as the crankshaft 5 of the engine 4. Next, the choke valve control device 27 that controls the opening and closing of the choke valve 25 will be described.
[0021]
4 to 10, a choke lever 28 is fixed to an upper end of the valve shaft 25a of the choke valve 25 protruding above the carburetor 23, and a stopper arm 28a integrated with the choke lever 28 is disposed on the upper surface of the carburetor 23. The fully open position of the choke valve 25 is defined by abutting against the projecting fully open stopper pin 29, and a choke spring 30 that biases the choke valve 25 toward the fully open position is applied to the choke lever 28. Connected. On the upper surface of the choke lever 28, a driven pin 31 protruding upward is integrally formed.
[0022]
The bracket 14 extends above the carburetor 23, and a choke operating lever 32 is pivotable between an open position O and a closed position C by a first pivot 33 on the lower surface of an extension portion formed in a flat plate shape. Attached to. The choke operating lever 32 is connected to a return spring 35 that biases the choke operating lever 32 toward the open position O.
[0023]
The choke operating lever 32, a first pivot 33 and concentric sector gear 36, a cam 37 disposed on the upper surface of the sector gear 36 is formed integrally, the sector gear 36, Kinobe length on the brackets 14 It is meshed with a pinion gear 39 of a rotary oil damper 38 attached to the lower surface of the part.
[0024]
As clearly shown in FIGS. 11 and 12, the oil damper 38 includes a damper housing 40 fixed to the extension portion of the bracket 14 with a screw 46, a rotor 41 rotatably accommodated in the damper housing 40, and a damper housing. The damper oil 42 is enclosed in a damper 40 and applies a damping force due to viscous resistance to the rotor 41. The damper oil 42 has a viscosity characteristic that increases the viscosity as the temperature decreases. The pinion gear 39 is fixed to the outer end of the rotating shaft 41a that is oil-tightly supported by the bearing portion of the damper housing 40 of the rotor 41. The sector gear 36 has a larger diameter than the pinion gear 39, and the gears 36 and 39 constitute a speed increasing mechanism 43 that speeds up and transmits the rotation of the cam 37 to the rotor 41.
[0025]
In FIG. 6, the cam 37 includes an inferior arc-shaped valley portion 37 a having a relatively small radius around the first pivot 33, a superior arc-shaped peak portion 37 b having a relatively large radius around the first pivot 33, The outer periphery has a cam surface composed of an inclined surface 37c that connects one end of the valley portion 37a and the peak portion 37b and an end wall surface 37d that connects the other ends thereof. A cam follower 44 that operatively connects the cam 37 and the choke lever 28 is attached to the flat bracket 14 by a second pivot 34 so as to be rotatable. The cam follower 44 has a protrusion 44 a that slidably contacts the cam surface of the cam 37, and a pressing spring 45 is connected to bring the protrusion 44 a into contact with the cam surface of the cam 37. When the choke operation lever 32 is in the open position O, the protrusion 44a is in contact with the valley portion 37a of the cam 37. When the choke operation lever 32 rotates from the open position O to the close position C by a predetermined angle, The contact position is moved to the peak portion 37b via 37c.
[0026]
An elastic drive plate 47 made of a leaf spring for driving the driven pin 31 of the choke lever 28 is connected to the mounting piece 44 a at the tip of the cam follower 44 by a screw 48. Thus, when the choke operating lever 32 is rotated to the closed position C, the cam follower 44 is rotated by the crest portion 37b of the cam 37 pressing the projection 44a, and the elastic drive plate 47 is moved accordingly. The choke valve 25 is fully closed via the choke lever 28 by pressing one side surface 31. Further, the choke operation lever 32 is still slightly rotated after the choke valve 25 is fully closed until the choke valve 25 reaches the closed position C, and the elastic drive plate 47 that continues to push the driven pin 31 is bent. Yes. By doing so, manufacturing errors of the respective parts of the choke valve control device 27 can be absorbed by the bending of the elastic drive plate 47, and the choke valve 25 can be always fully closed.
[0027]
As shown in FIGS. 4 to 6, a small bracket 54 is formed on the upper surface of the bracket 14 so as to stand upward. A lock lever that restrains or releases the choke operation lever 32 at the closed position C is provided. 50 is pivotally attached by a pivot 51. That is, the lock lever 50 is provided with a locking claw 50 a that penetrates the guide hole 52 of the extended portion of the bracket 14 to the cam 37 side and retreats upward from the cam 37. A lock spring 55 is connected to the lock lever 50 so as to be biased upward. When the choke operation lever 32 comes to the closed position C, the latching claw 50a can engage with the absolute wall surface 37d of the cam 37 to lock the choke operation lever 32 to the closed position C. The lock lever 50, the lock spring 55, and the wall face 37d constitute a lock mechanism 49 that can lock the choke operation lever 32 in the closed position C.
[0028]
The lock lever 50 is connected to the brake shoe 16 via a link 53, and is rotated so that the locking claw 50a is detached from the cam 37 in conjunction with the rotation of the brake shoe 16 to the brake release position B. It has become so.
[0029]
The choke valve control device 27 is arranged so that the upper surface of the choke valve control device 27 is covered together with the engine 4 by the engine cover 4 and faces the cooling air path from the cooling air inlet 13 to the engine 4. However, as shown in FIG. 2, the choke operation lever 32 is arranged so that the tip portion protrudes outward from the engine cover 4 so that the operator can easily rotate it. .
[0030]
Next, the operation of this embodiment will be described.
[0031]
When the brake shoe 16 is in the braking position A and applying a braking force to the flywheel 9, the lock lever 50 is rotated downward by the urging force of the lock spring 55 as shown in FIGS. Thus, the locking claw 50 a is pressed against the upper surface of the cam 37 through the guide hole 52 in the extension portion of the bracket 14.
[0032]
When the engine 4 is started in cold weather, first, as shown in FIGS. 6 and 7, the choke operation lever 32 of the carburetor 23 is rotated to the closed position C while the return spring 35 is extended, The cam follower 44 is rotated by the mountain portion 37b, and the driven pin 31 is pressed from the side by the elastic drive plate 47, so that the choke valve 25 is fully closed. At this stage, the locking claw 50 a of the lock lever 50 biased downward is engaged with the absolute wall surface 37 d of the cam 37. In this case, even if the operating force is released from the choke operating lever 32, the choke operating lever 32 is locked at the closed position C, and the return spring 35 remains in an extended state.
[0033]
Next, by holding the brake release lever 20 together with the steering handle 6 and pulling the operation wire 21, the brake shoe 16 is rotated to the brake release position B (see FIG. 8) to release the braking force on the flywheel 9. To do. Therefore, the crankshaft 5 is free to rotate. At this time, the engine kill switch 22 is deactivated by the brake shoe 16 (the ignition circuit can be activated). At the same time, the brake shoe 16 pulls the lock lever 50 via the link 53 and cams the locking claw 50a. The cam 37 is released from the wall 37d.
[0034]
As a result, the choke operation lever 32 starts to return toward the opening position O by the urging force of the return spring 35, but the sector gear 36 integrated with the choke operation lever 32 rotates the rotor 41 of the oil damper 38 via the pinion gear 39. Therefore, the rotor 41 receives a damping force due to viscous resistance from the damper oil 42, and this action slowly controls the rotation of the choke operation lever 32 toward the opening position O. Moreover, the choke valve 25 can be kept in the fully closed state while the choke operation lever 32 is returned and rotated while the arc-like peak portion 37b of the cam 37 presses the projection 44a of the cam follower 44. .
[0035]
In addition, since the rotation of the cam 37 is accelerated by the sector gear 36 and the pinion gear 39 and transmitted to the rotor 41, the damper 38 generates a sufficient damping force even if it is compact, and the rotation speed of the choke operating lever 32 is accurately adjusted. Can be controlled.
[0036]
Therefore, if the engine 4 is cranked by operating the recoil starter 11 immediately after the brake shoe 16 is turned to the brake release position B, the carburetor 23 is suitable for cold start because the choke valve 25 is fully closed. A rich air-fuel mixture is generated, and the engine 4 that has sucked it can be started quickly.
[0037]
Even after the engine 4 is started, as described above, the choke valve 25 is maintained in the fully closed state for a relatively long time by the action of the damper 38 and the crest portion 37b of the cam 37, so that a stable warm-up operation state is ensured. can do.
[0038]
When the cam 37 is rotated by the urging force of the return spring 35 and the contact position of the projection 44a of the lock lever 50 with the cam 37 is moved from the peak portion 37b to the valley portion 37a, the elastic drive plate 47 is separated from the driven pin 31. (See FIGS. 9 and 10) The choke valve 25 is automatically fully opened by the urging force of the choke spring 30, and the concentration of the air-fuel mixture generated by the vaporizer 23 becomes a normal value.
[0039]
In this way, the locked state of the choke operation lever 32 is automatically released by using the rotation of the brake shoe 16 to the brake release position B, so that a special return operation of the choke operation lever 32 is not necessary. In addition to reducing the burden on the engine 4, it is possible to prevent malfunction of the engine 4 and deterioration of fuel consumption due to forgetting to open the choke valve 25.
[0040]
By the way, the viscous resistance of the damper oil 42 in the oil damper 38 has a characteristic that it increases as the temperature decreases and decreases as it increases, so that the damping force generated by the damper 38 decreases as the environmental temperature of the engine 4 decreases. By increasing, the required time from the fully closed to the fully opened choke valve 25 is long. On the contrary, when the environmental temperature becomes high, the required time is automatically controlled to be short. Thereby, engine startability, stability of warm-up operation, and low fuel consumption can be satisfied.
[0041]
Further, the damper 38 including the damper housing 40, the rotor 41, and the damper oil 42 has a small number of parts and is compact, which can contribute to cost reduction and downsizing of the choke valve control device 27.
[0042]
Further, since the rotor 41 of the damper 38 can be rotated in the forward and reverse directions, even when the choke operation lever 32 is accidentally operated to the closing side during warming, the reverse operation force is applied to the choke operation lever 32 to the open position O. It can be returned immediately.
[0043]
When the engine 4 is started, the crankshaft 5 drives the cutting blade 7 to rotate, so that the operator pushes the lawn mower 1 while holding the steering handle 6 together with the brake release lever 20 to perform the lawn mowing work. it can. During this lawn mowing operation, the cooling air is drawn into the engine cover 10 from the cooling air intake 13 by the rotation of the flywheel 9 also serving as a cooling fan, and passes through the choke valve control device 27 in the process of being pumped to each part of the engine 4. At that time, the dust attached to the choke valve control device 27 is blown away for cleaning. Further, the choke valve control device 27 including the choke operation lever 32, the cam 37, the damper 42, and the like is attached to the lower surface of the extension portion of the bracket 14, and it is difficult for dust to adhere to it, so that the cleaning effect is enhanced. become. Therefore, it is possible to avoid the dust that has been raised during mowing by the cutting blade 7 from accumulating on the choke valve control device 27 and to prevent its malfunction, and to cool the device 27 as well. , It can also increase its durability.
[0044]
In addition, the choke operating lever 32 has a tip projecting outward from the engine cover 10, so that the operating lever 32 can be easily opened and closed without being obstructed by the engine cover 10. Therefore, the position of the operation lever 32 can be easily confirmed, and the choke valve 25 can be controlled easily and accurately.
[0045]
Cooling air that has cooled each part of the engine 4 is discharged from the periphery of the engine 4 to the outside.
[0046]
Next, if the operating force is released from the brake release lever 20 to stop the operation of the engine 4, the brake shoe 16 swings to the braking position A by the urging force of the brake spring 19, and the engine kill switch accordingly. 22 operates to deactivate the ignition circuit, so that the inertial rotation of the crankshaft 5 and the cutting blade 7 can be quickly stopped by the friction braking force applied to the outer peripheral surface of the flywheel 9 by the brake shoe 16.
[0047]
On the other hand, the lock lever 50 is released from the brake shoe 16 swinging to the braking position A, and is rotated downward by the urging force of the lock spring 55 to press the locking claw 50a against the upper surface of the cam 37. In preparation for locking the operating lever 32 to the closed position C.
[0048]
The present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the scope of the invention. For example, instead of the elastic drive plate 47 and the driven pin 31, as shown in FIG. 13, an extension arm 44 c formed integrally with the cam follower 44 can be connected to the choke lever 28 via a link 57. In FIG. 13, the same reference numerals are assigned to the portions corresponding to the above-described embodiment, and the description thereof is omitted. The shape of the cam surface of the cam 37 is freely selected according to the required valve opening characteristics of the choke valve 25.
[0049]
【The invention's effect】
As described above, according to the first feature of the present invention, the cooling fan is attached to the upper end of the crankshaft arranged in the vertical direction, and the engine having the work implement connected to the lower end of the shaft is opposed to the cooling fan. An engine cover that covers the upper surface of the engine with a cooling air intake and guides the cooling air taken from the cooling air intake by the cooling fan to the engine, a carburetor attached to one side of the engine, and this vaporization The choke control lever that opens and closes the choke valve of the detector, the choke spring that urges the valve in the valve opening direction, and when the valve opens from the fully closed position with the urging force of the choke spring, the valve opening operation is slow. And a choke valve control device comprising a slow return means for controlling the choke valve control device, wherein the choke is provided in the cooling air path from the cooling air intake to the engine. Since the valve control device is arranged, the dust that adheres to the choke valve control device can be blown away and cleaned by the engine cooling air generated by the cooling fan during the operation of the engine, and is therefore lifted by the work implement It is possible to avoid the accumulation of dust on the choke valve control device and prevent its malfunction, and it is also possible to cool the device and enhance its durability. Further, since the mounting of the choke valve control device to the lower surface of the extended portion of the bracket, dust hardly adheres, the cleaning effect can be highly Mel.
[0050]
According to the second feature of the present invention, in addition to the first feature, the tip of the choke operation lever protrudes outward from the engine cover, so that the choke operation lever is not obstructed by the engine cover. Since the lever can be easily opened and closed, and the lever can be visually checked, the position of the lever can be easily confirmed, and accurate control of the choke valve can be easily performed.
[Brief description of the drawings]
FIG. 1 is a side view of a power lawn mower equipped with an engine equipped with a choke valve control device according to an embodiment of the present invention.
FIG. 2 is a partially broken plan view of the engine.
3 is a cross-sectional view taken along line 3-3 in FIG.
4 is a side view of the main part of FIG. 3;
FIG. 5 is a view taken in the direction of arrows 5-5 in FIG. 4 (showing the operating state of the braking mechanism and the fully opened state of the choke valve).
6 is a cross-sectional view taken along line 6-6 in FIG. 4 (however, the choke valve is shown in a fully closed state).
FIG. 6 is a view taken in the direction of arrow 7.
FIG. 8 is a view corresponding to FIG. 5 showing the brake mechanism in a released state and the choke valve in a fully closed state.
FIG. 9 is a view corresponding to FIG. 5 showing the brake mechanism release state and the choke valve fully open state.
FIG. 10 is a view corresponding to FIG. 6 showing the choke valve fully opened.
11 is an enlarged plan view of a damper portion in FIG.
12 is a cross-sectional view taken along line 12-12 in FIG.
FIG. 13 is a diagram corresponding to FIG. 6, showing another embodiment of the present invention.
[Explanation of symbols]
1 ... Power working machine (Power lawn mower)
4 ... Engine 5 ... Crankshaft 7 ... Work implement (cutting blade)
9. Cooling fan (cooling fan and flywheel)
10 .... Engine cover 13 ... Cooling air inlet 23 ... Vaporizer 25 ... Choke valve 27 ... Choke valve control device 30 ... Choke spring 32 ... .Choke operating lever 38... Slow return means (damper)

Claims (1)

An engine (4) having a cooling fan (9) attached to the upper end of the crankshaft (5) arranged in the vertical direction and a work implement (7) connected to the lower end of the shaft (5), and a cooling fan (9) The cooling air intake (13) opposite to the engine (4) is covered and the upper surface of the engine (4) is covered, and the cooling air taken from the cooling air intake (13) by the cooling fan (9) is guided to the engine (4). An engine cover (10); a carburetor (23) attached to one side of the engine (4); a choke operation lever (32) for opening and closing a choke valve (25) of the carburetor (23); 25) When the valve (25) is opened from the fully closed position by the biasing force of the choke spring (30), the valve opening operation is slowly controlled. Comprising slow return means (38) In Yoku valve control device (27) and a motive power working machine,
The choke valve control device (27) is arranged in the cooling air path from the cooling air intake (13) to the engine (4), and the choke valve control device (27) is connected to the engine (4). A cleaning structure for a choke valve control device in a power working machine, wherein the cleaning structure is attached to a lower surface of an extension portion of a fixed bracket (14) .

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