WO2007132915A1

WO2007132915A1 - Portable work machine

Info

Publication number: WO2007132915A1
Application number: PCT/JP2007/060121
Authority: WO
Inventors: Yuu Sugishita
Original assignee: Husqvarna Zenoah Co., Ltd.
Priority date: 2006-05-17
Filing date: 2007-05-17
Publication date: 2007-11-22
Also published as: TW200800533A; JP2007309166A

Abstract

A chain saw (1), a portable work machine, has a body (11) for receiving an engine (15), a cooling fan (19) driven by the engine (15), a carburetor (36) for producing a mixture gas for the engine (15), an intake air communication path (37) for directly interconnecting the vicinity of the cooling fan (19) and an air intake path of the carburetor (36), and an air cleaner (25) provided in the middle of the intake air communication path (37), outside a carburetor chamber (43) where the carburetor (36) is received. At least that portion of the intake air communication path (37) that is on the downstream side of the air cleaner (25) is a closed space.

Description

Specification

Portable work machine

Technical field

TECHNICAL FIELD [0001] The present invention relates to a portable work machine such as a chain saw, a hand saw, or a brush cutter, and more particularly to an improvement of an intake system of an engine mounted on the portable work machine.

Background art

[0002] Conventionally, in a portable working machine driven by a small engine such as a chain saw, an intake system for sucking and trapping dust such as chips and chips generated during work into a cap chamber in which a carburetor is housed. Are used in various ways. As an example, the air chamber is connected to the vicinity of a cooling fan driven by an engine through an intake passage, and clean air intake, in which dust is separated by a centrifugal separation function by the cooling fan, is transferred to the cap chamber via the intake passage. An intake system for sending air has been proposed (for example, Patent Document 1).

[0003] According to this air intake system, since the intake air with less dust is sent to the cabin, the amount of dust collected by the air cleaner (air filter) attached to the carburetor can be suppressed in the cabin, and maintenance of the air cleaner is possible. The frequency can be reduced. Also, in this intake system, the case where the negative pressure generated on the cooling fan side is larger than the suction force in the engine is used, dust collected by the air cleaner is removed by the negative pressure and the intake passage is used. It is also possible to return to the fan side, thus further reducing the maintenance frequency of the air cleaner

[0004] Patent Document 1: Japanese Patent Laid-Open No. 6-173797

Disclosure of the invention

Problems to be solved by the invention

[0005] By the way, the air cleaner is attached to the carburetor and accommodated in the cabin, but the inside of the cabin is not strictly sealed depending on the structure. For example, an open / close lid for air cleaner maintenance There may be a slight gap around the center of the housing or in the mating portion of the members forming the chamber. For this reason, this slight gap force dust enters, and the air cleaner gets dirty and the maintenance frequency is high. Cannot be reduced, and there is a problem that the dust around the carburetor adheres and needs to be cleaned.

An object of the present invention is to provide a portable work machine that can send clean air to a carburetor and can greatly simplify troublesome maintenance around the carburetor.

Means for solving the problem

[0007] A portable work machine of the present invention includes a main body that houses an engine, a cooling fan that is driven by the engine, a carburetor that generates an air-fuel mixture to the engine, and the vicinity of the cooling fan. An intake communication passage that directly communicates with the intake passage of the carburetor, and an air cleaner disposed in the middle of the intake communication passage and outside the cap chamber in which the carburetor is accommodated. It is characterized by.

[0008] According to the present invention, since the intake communication passage that connects the vicinity of the cooling fan and the intake passage of the carburetor is provided, clean intake air from which dust has been removed by the centrifugal separation function on the cooling fan side is provided. Can be sent to. In addition, the air cleaner is disposed outside the chamber, and the intake communication passage is directly connected to the intake passage of the carburetor, and the passage portion downstream of the air cleaner in the intake communication passage is closed. Therefore, the suction force of the engine can be prevented from acting on the cap chamber, and there is no concern of dust entering through the gap in the cap chamber and contaminating the carburetor periphery, greatly reducing the labor required for maintenance.

[0009] In the portable work machine of the present invention, it is preferable that the air cleaner is disposed near the suction port on the cooling fan side of the intake communication path.

[0010] According to the present invention, the air cleaner is disposed near the intake port on the cooling fan side in the intake communication path, so that the negative pressure generated on the cooling fan side can be effectively applied to the vicinity of the air cleaner. The dust collected in can be removed and returned to the cooling fan.

[0011] In the portable work machine according to the present invention, a gap communicating with the outside may be formed at a position corresponding to the vicinity of the air tallyer on the upstream side of the air cleaner in the intake communication path. preferable. [0012] According to the present invention, the negative pressure acting in the vicinity of the air cleaner sucks the outside air through the gap toward the air cleaner, and the dust can be effectively removed by the sucked outside air, thereby greatly improving the removal function. This can reduce the frequency of air cleaner maintenance.

Brief Description of Drawings

FIG. 1 is a perspective view showing the overall outline of a portable work machine according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a main part in the portable work machine.

FIG. 3 is a perspective view of the portable work machine viewed from below.

FIG. 4 is a side view showing a part of the main part.

[FIG. 5] A view of the part as seen from the rear side.

Explanation of symbols

[0014] 1 ... Chainsaw that is a portable work machine, 11 ··· Body body, 15 ··· Engine, 19 ··· Cooling fan, 25 ··· Air cleaner, 31 ··· Suction port, 36 ··· · Carburetor, 37 · · · Air intake passage, 38 · · · Clearance, 42 · · · Air intake passage, 43 · · · Cab room.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an overall outline of a chainsaw (portable work machine) 1 according to the present embodiment. FIG. 2 is a perspective view showing a main part in the chainsaw 1. FIG. 3 is a perspective view of the chain saw 1 as viewed from below. FIG. 4 is a side view showing a part of the main part, and FIG. 5 is a part of the part as seen from the rear side.

[0016] The chainsaw 1 is a type having a top handle 12 above the main body body 11, with one end on the side of the top handle 12 and the other end on the front side of the top handle 12. A separate handle 14 is provided below the rear portion of the body 11 and is connected together with a part of the fuel tank 13. Here, the fuel tank 13 of the present embodiment is provided integrally with the top handle 12.

As shown in FIG. 2, a small two-cycle engine 15 is accommodated in the main body 11. However, in FIG. 2, the crankcase of the engine 15 is not shown. One end of the crankshaft 16 protruding from the engine 15 is not shown in the figure. The sprocket is pivotally supported via the hose, and the saw chain 18 wound around the sprocket and the guide bar 17 beside the main body 11 is driven by the engine 15.

[0018] A cooling fan 19 having a plurality of fins on the circumference is attached to the other end of the crankshaft 16. A fan case 21 having an air inlet 20 is disposed outside the cooling fan 19. A volute corresponding to the outer periphery of the cooling fan 19 is formed on the back surface of the fan case 21. This volute functions as a ventilation path that sends out the sucked cooling air to the engine 15 side.

On the surface of the fan case 21, a communication path forming part 24 having two partition parts 22, 23 is provided on the body. A mounting portion 26 to which a cartridge type air cleaner 25 is attached is provided on the vertical surface portion on the rear side of the communication path forming portion 24. The mounting portion 26 has a U-shaped protruding partial force, and an engaging groove is formed between the protruding portion and the planar portion. The air cleaner 25 also drops the upward force with respect to the engaging groove of the mounting portion 26. It is included.

As described above, in the present embodiment, the air cleaner 25 is disposed on the side of the main body 11. Conventionally, this side part used to be the space for the intake communication path that connects the vicinity of the cooling fan and the cap chamber. By using this space for forming the communication path as the space for arranging the air cleaner 25, The air cleaner 25 can be arranged without increasing the size of the main body 11 in which the air cleaner 25 is accommodated, and it is not necessary to arrange the air cleaner 25 in the top handle 12 in which the carburetor 36 is accommodated. We are trying to make it slimmer.

In FIG. 4, an opening 26A is provided in the planar portion surrounded by the attachment portion 26, and one end of the hollow first communication member 27 is fitted into the opening 26A in a grommet manner. . This state is shown in FIG. 4 with the air cleaner 25 partially broken.

On the other hand, the outside of the fan case 21 is covered with a cover 29 having a large number of ventilation holes 28. A recoil starter (not shown) that is connected to the cooling fan 19 via a ratchet mechanism is attached to the back side of the cover 29, and a partition wall 30 that protrudes toward the fan case 21 side is provided. Is provided.

A part of the partition wall 30 is in contact with the partition portions 22 and 23 on the fan case 21 side. In addition, The other part of the cut wall 30 protrudes into the air inlet 20 of the fan case 21, and the opening formed by the protruding part and the inner edge of the air inlet 20 faces the disk-shaped part of the cooling fan 19. It is located at the inlet 31 (Fig. 4). In the vertical surface portion of the fan case 21, the lower edge and the rear vertical edge along the U-shaped attachment portion 26 are covered with the cover 29.

[0024] Further, in the cover 29, a portion facing the air cleaner 25 is opened, and an opening / closing lid 32 is attached to the opening portion. A hinge 33 is provided on the lower side of the opening / closing lid 32, and this hinge 33 is pivotally supported by the cover 29, whereby the opening / closing lid 32 is opened and closed in a rotating manner. Further, an engaging claw 34 is provided on the upper side of the opening / closing lid 32, and the engaging claw 34 is configured to be engageable with and disengageable from an engaging hole 29A provided on the upper surface of the cover 29.

[0025] Desorption work or the like of the air cleaner 25 is performed by opening and closing the opening / closing lid 32. More specifically, the engaging claw 34 is removed from the engaging hole 29A, the opening / closing lid 32 is opened, and the air cleaner 25 is moved upward from the mounting portion 26 using the upper opening formed at this time. They can be pulled out or inserted from the top down.

[0026] Power! As shown in FIG. 5, a partition piece 35 protruding toward the fan case 21 is provided on the back side of the opening / closing lid 32. When the opening / closing lid 32 is closed, the tip of the partitioning piece 35 is provided. The side is brought into contact with the upper edge of the air cleaner 25. As a result, the periphery of the communication path forming portion 24 of the fan case 21 is covered in a semi-sealed state by the cover 29 and the opening / closing lid 32. The semi-enclosed space forms an upstream side (upstream side from the air cleaner 25) of the intake communication path 37 that allows the vicinity of the cooling fan 19 and the carburetor 36 in the top handle 12 to communicate with each other.

As shown in FIG. 3, on the side of the hinge 33 of the opening / closing lid 32, a gap 38 communicating with the outside is intentionally formed between the opening / closing lid 32 and the cover 29. The operation of this gap 38 will be described later. Further, since such a gap 38 is provided below the opening / closing lid 32, rainwater or the like is difficult to enter.

[0028] Now, the first communication member 27 fitted into the opening 26A of the fan case 21 extends to the cap chamber 43 in the top handle 12 provided above. As shown in FIGS. 4 and 5, the upper end of the first communication member 27 is fitted in a second communication member 39 formed in a hollow flat box shape. Specifically, the second communication member 39 includes an intake inlet 40 and an intake outlet 41. The upper end of the first communication member 27 is connected to the intake inlet 40.

[0029] The second communication member 39 is configured to be screwed to the carburetor 36. When the second communication member 39 is attached to the carburetor 36, the intake air outlet 41 of the second communication member 39 is provided in the intake passage 42 of the carburetor 36. It is in direct contact. The internal spaces of the first and second communication members 27 and 39 that are in communication with each other are closed spaces, and intake air does not enter from other than the opening 26A.

[0030] The downstream side of the intake communication passage 37 (downstream side from the air cleaner 25) is formed by the first and second communication members 27 and 39. Further, according to the present embodiment, the air cleaner 25 is disposed outside the cap chamber 43 in which the carburetor 36 is accommodated and near the suction port 31 in the middle of the intake communication path 37.

[0031] In the above embodiment, the intake air including the dust sucked from the large number of ventilation holes 28 by the cooling fan 19 is sucked in the axial direction with respect to the cooling fan 19 through the air suction port 20 of the fan case 21, After this, the direction is changed to the outside in the radial direction and sent to the outer periphery of the outer peripheral air passage force engine 15 to cool the cylinder and the like.

A part of the cooling air is sucked into the engine 15 by the suction force of the engine 15 through the suction port 31, the intake communication path 37, and the carburetor 36 as a mixture with fuel. The dust in the cooling air sucked in by the cooling fan 19 is blown past the intake port 31 by the centrifugal force after the flow of the cooling air is converted from the axial direction to the radial direction, and reaches the air passage. It rides on the cooling air that cools 15 and is finally discharged to the outside of the main body 11.

Accordingly, the dust sucked from the suction port 31 can be reduced, and the amount of dust collected by the air cleaner 25 can be reduced to reduce the maintenance frequency. Further, in the intake communication passage 37, the space downstream of the air cleaner 25 is a closed space and directly communicates with the intake passage 42 of the carburetor 36. Therefore, the suction force of the engine 15 does not act on the carburetor 36, which has a small amount of dust in the atmosphere entering through a small gap in the cap chamber 43, and can be effectively prevented from being contaminated with dust.

[0034] By the way, when the throttle 44 is returned and the rotational speed of the engine 15 is lowered to the idling rotational speed, the throttle valve of the carburetor 36 is closed at that moment, and the intake communication passage 37 is more than the suction force by the engine 15 Cooling fan 19 that maintains rotational force with inertial force Since the negative pressure becomes larger, a large amount of outside air is sucked from the gap 38 located below the air cleaner 25, and dust collected by the air cleaner 25 is removed and returned to the cooling fan 19 side. It can be put on and finally discharged to the outside.

[0035] The best configuration, method, and the like for carrying out the present invention have been disclosed above, but the present invention is not limited to this. In other words, the present invention is mainly illustrated and described mainly with respect to specific embodiments. However, the present invention is not limited to the above-described embodiments without departing from the technical spirit and scope of the invention. Various modifications can be made by those skilled in the art in terms of quantity and other detailed configurations. Accordingly, the description of the shape, quantity and the like disclosed above is exemplary only for easy understanding of the present invention, and does not limit the present invention. In addition, description in the name of a member excluding some or all of the limitations such as quantity is included in the present invention.

For example, in the embodiment, the gap 38 is intentionally formed on the lower side of the opening / closing lid 32. However, such a gap is not formed, and the area around the communication path forming portion 24, that is, the intake air is formed. The upstream side of the air cleaner 25 in the communication passage 37 may be sealed except for the suction port 31 and the opening 26A. Even in such a case, the air cleaner 25 is arranged closer to the suction port 31 so that the negative pressure on the cooling fan 19 side can be applied in the vicinity of the air cleaner 25 and the dust collected by the air cleaner 25 can be removed. Can be performed satisfactorily. Industrial applicability

[0037] The present invention is not limited to a chain saw, and can be used for all portable work machines such as a cut-off saw, a brush cutter, and a blower.

Claims

The scope of the claims

[1] In portable work machines,

A body body that houses the engine;

A cooling fan driven by the engine;

A carburetor for generating an air-fuel mixture to the engine;

An intake communication passage that directly connects the vicinity of the cooling fan and the intake passage of the carburetor;

And an air cleaner disposed in the middle of the intake communication path and outside the cap chamber in which the carburetor is accommodated.

A portable work machine characterized by that.

[2] The portable work machine according to claim 1, wherein

The air cleaner is disposed near the suction port on the cooling fan side of the intake communication path.

A portable work machine characterized by that.

[3] In the portable work machine according to claim 2,

A gap communicating with the outside is formed at a position corresponding to the vicinity of the air cleaner on the upstream side of the air cleaner in the intake communication path.

A portable work machine characterized by that.