JP4705538B2 - Air cleaner - Google Patents

Description

  The present invention relates to an air cleaner for purifying air supplied to an engine.

As an air cleaner for purifying air supplied to an engine mounted on a small work machine such as a chain saw or a brush cutter, it has a cleaner case divided into an upper upper case and a lower lower case. Some cleaner elements are attached between the upper case and the lower case.
The upper case is formed with an intake port for taking in external air, and the lower case is formed with an exhaust port for supplying air that has passed through the cleaner element to the engine.
The cleaner case is provided with a connecting pipe having one opening communicating with the exhaust port of the lower case and the other opening communicating with the intake passage of the engine. And the connection pipe | tube of the conventional air cleaner becomes a structure which connected the some tubular member in the extension direction (for example, refer patent document 1).

Japanese Patent Laying-Open No. 2005-256635 (paragraph 0024, FIG. 1)

However, in the conventional air cleaner described above, dust such as chips generated at the time of cutting work may enter the connecting pipe from the connection portion of the cleaner case and the connecting pipe or the joint of the connecting pipe, and the air supplied to the engine There is a problem that the purification performance of the water is reduced.
Further, since the connecting pipe is composed of a plurality of parts, there are problems that the number of parts of the air cleaner increases, the manufacturing cost increases, and the work of assembling the air cleaner becomes complicated.

  Accordingly, the present invention has an object to provide an air cleaner that can solve the above-described problems, improve the purification performance of air supplied to the engine, reduce the manufacturing cost, and can be easily assembled. To do.

In order to solve the above problems, the present invention is an air cleaner for purifying air supplied to an engine, and has a cleaner case to which a cleaner element for purifying air is attached, and the cleaner case receives air from the outside. An intake port for intake is formed, and an exhaust port for supplying air that has passed through the cleaner element to the engine is formed. One opening communicates with the exhaust port of the cleaner case, and the other opening Has a connecting part formed with a flow path communicating with the intake passage of the engine, the cleaner case and the connecting part are integrally formed, and the inner peripheral surface of the connecting part is recessed in the bent part of the flow path The expansion space formed in is formed in a position facing the other opening so as to face the other opening .

According to this configuration, the connecting portion in which the flow path communicating with the exhaust passage of the cleaner case and the intake passage of the engine is formed is formed integrally with the cleaner case, and the connection between the cleaner case and the connecting portion is performed. Since no seam is formed at the location or the connecting portion, dust such as chips can be prevented from entering the connecting portion.
Further, since the cleaner case and the connecting portion are integrally formed, the number of parts of the air cleaner is reduced, so that the manufacturing cost of the air cleaner can be reduced and the air cleaner can be easily assembled.
Here, the state in which the cleaner case and the connecting part are integrally formed is a state in which the cleaner case and the connecting part are formed as one continuous part by, for example, injection molding or the like. Note that a part of the cleaner case may be configured to be detachable in consideration of replacement of the cleaner element and maintenance.

Further, when the fuel gas is blown back from the engine, the fuel gas is blown into the expansion space from the other opening. As a result, the fuel gas blown back from the engine can be prevented from being directly ejected into the cleaner case, and the deterioration of the cleaner element due to the adhesion of fuel and oil contained in the fuel gas can be prevented.

  The above-described air cleaner can be configured such that a current plate for guiding the air taken into the cleaner case to the exhaust port is provided inside the cleaner case.

  According to this configuration, since the air in the cleaner case is guided to the exhaust port by the rectifying plate, not only the air is taken into the exhaust port from the extension direction of the exhaust port as in the past, but also rectified from around the exhaust port. The air guided by the plate can be taken into the exhaust port, and the range in which the air is taken into the cleaner case can be expanded. As a result, air is taken in from a wide range of the cleaner element, and the flow rate per unit area of the air passing through the cleaner element can be reduced, so that the maintenance period of the cleaner element can be extended.

  In the above-described air cleaner, the cleaner case can be configured such that a reflecting plate is provided at a position facing the exhaust port.

  According to this configuration, since the reflecting plate is provided at a position facing the exhaust port, the fuel gas that has flowed back into the cleaner case when the fuel gas blows back from the engine is reflected by the reflecting plate and exhausted. It will be returned to the mouth. Thereby, deterioration of the cleaner element due to adhesion of fuel and oil contained in the fuel gas can be prevented.

  Further, by providing the reflecting plate at a position facing the exhaust port, air is taken into the exhaust port from the periphery of the reflecting plate, so that the range in which air is taken into the cleaner case can be expanded. As a result, air is taken in from a wide range of the cleaner element, and the flow rate per unit area of the air passing through the cleaner element can be reduced, so that the maintenance period of the cleaner element can be extended.

  The above-described air cleaner can be configured such that ribs are erected on the outer peripheral edge of the surface of the reflecting plate that faces the exhaust port.

  According to this configuration, the rib is erected on the outer peripheral edge of the surface facing the exhaust port in the reflector, and when the fuel gas blown back from the engine is reflected by the reflector, the fuel gas is separated by the rib. Since the spread in the lateral direction is suppressed, the fuel gas can be returned to the exhaust port without being scattered in the cleaner case.

According to the air cleaner of the present invention, the connecting portion in which the flow path communicating with the cleaner case and the engine is formed integrally with the cleaner case, and there is a joint at the connecting portion of the cleaner case and the connecting portion, and at the connecting portion. Since it is not formed, dust such as chips can be prevented from entering the connecting portion, and the purification performance of the air supplied to the engine can be improved.
Further, since the cleaner case and the connecting portion are integrally formed, the number of parts of the air cleaner is reduced, so that the manufacturing cost of the air cleaner can be reduced and the air cleaner can be easily assembled.

Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
In the present embodiment, an air cleaner provided in a chain saw that is a small work machine will be described as an example. First, the overall structure of the chain saw of the present embodiment will be described, and then the air cleaner will be described in detail.
FIG. 1 is a perspective view of the chain saw body of the present embodiment as viewed obliquely from above. FIG. 2 is a perspective view of the air cleaner according to the present embodiment as viewed obliquely from above. FIG. 3 is an exploded perspective view showing the air cleaner of the present embodiment. FIG. 4 is a rear view of the air cleaner according to the present embodiment. FIG. 5 is a view showing the air cleaner of the present embodiment, and is a cross-sectional view taken along the line AA of FIG.
In the following description, the front-rear direction corresponds to the front-rear direction shown in each drawing.

[Configuration of chain saw]
As shown in FIG. 1, the chain saw 1 includes a main body portion 2 including an air cleaner 10 and an engine E, and a handle portion 3 that supports the main body portion 2.
The chain saw 1 of the present embodiment has substantially the same configuration as a conventionally known chain saw except for the configuration of the air cleaner 10 provided in the main body 2, and therefore detailed description of the overall configuration of the chain saw 1 is omitted. .

(Configuration of main unit)
The main body 2 has drive mechanisms such as an air cleaner 10 and an engine E, and this drive mechanism is accommodated in an upper cover (not shown).
The engine E is disposed at the front portion of the main body 2, and the air cleaner 10 is disposed behind the engine E.
The upper cover is detachable from the main body 2 together with the lower cover 2b. In FIG. 1, the upper cover is removed to illustrate the air cleaner 10 and the engine E. However, in the normal state, the upper cover is attached to the main body 2 and the air cleaner 10 and the engine E are covered by the upper cover. It is in the state. The upper cover is formed with a vent for taking outside air into the upper cover.

Further, in the main body 2, the rear end portion of the guide bar 4 is attached to the side portion on the right side in FIG.
The guide bar 4 is a plate-like member extended in the front-rear direction, and an annular saw chain (not shown) is wound around the outer peripheral portion thereof.
The rear portion of the saw chain is engaged with a sprocket (not shown) connected to the engine E of the main body 2 so that the saw chain rotates along the outer periphery of the guide bar 4 by the driving force of the engine E. It is configured.

(Composition of handle part)
The handle portion 3 includes a front handle 3 a and a rear handle 3 b, and the main body portion 2 is supported by the handle portion 3 by attaching the main body portion 2 to the front portion of the handle portion 3.
The front handle 3a is a grip portion disposed on the outer periphery of the main body 2 and is formed by bending a cylindrical member. The front handle 3a is extended in the width direction at a position spaced apart from the upper surface of the main body 2, and both ends thereof are bent downward and attached to both sides of the handle 3, respectively. Yes.
The rear handle 3b is provided at the rear end portion of the handle portion 3, and is an operating means for starting and stopping the rotation of the saw chain (not shown) while being gripped by the operator.

(Cutting work with a chain saw)
An operator carries the chain saw 1 by holding the front handle 3a with one hand and holding the rear handle 3b with the other hand. In a state where the lock lever 3c is pushed, the throttle lever 3d is operated to rotate the saw chain (not shown) along the outer periphery of the guide bar 4, so that trees or the like can be cut by the saw chain.
An emergency brake is provided at the upper front portion of the main body 2 to stop the rotation of the saw chain when the operator's hand touches and tilts forward when a kickback occurs in the cutting saw 1 during the cutting operation. A lever 2c is provided.

[Configuration of air cleaner]
Next, the structure of the air cleaner 10 provided in the chain saw 1 of the above-described embodiment will be described.
As shown in FIGS. 2 and 3, the air cleaner 10 according to the present embodiment includes a cleaner case 11 to which a cleaner element (not shown) for purifying air is attached. The cleaner case 11 includes an upper upper portion. It is divided into a case 12 and a lower lower case 13. Further, a connecting portion 20 connected to the engine E (see FIG. 1) is formed integrally with the lower case 13 on the lower surface of the lower case 13.
In the present embodiment, the cleaner case 11 and the connecting portion 20 are formed of a plastic material, but the material is not limited.

(Configuration of upper case)
As shown in FIGS. 2 and 3, the upper case 12 has a quadrilateral frame formed by the outer peripheral wall portion 12 a having a substantially rectangular shape in plan view, and the inner space of the outer peripheral wall portion 12 a is externally provided. An air inlet 12b for taking air into the cleaner case 11 is provided.
A support member 12c that forms a lattice in the air inlet 12b is formed at the upper end portion of the outer peripheral wall portion 12a, and a locking projection 12d protrudes inward at the lower end portion of the outer peripheral wall portion 12a. It is installed.

  As shown in FIG. 3, in the support member 12c, a trapezoidal reflection plate 12e is formed in a plan view at a position facing an exhaust port 13c of the lower case 13 to be described later, and the reflection plate 12e is formed on the support member 12c. It is formed on the lower surface side. Further, as shown in FIG. 5, ribs 12f are erected over the entire periphery at the outer peripheral edge of the lower surface of the reflecting plate 12e.

Further, as shown in FIG. 5, a nylon mesh cleaner element 30a is pressure-bonded to the upper surface of the upper case 12 so as to cover the air inlet 12b. As a result, the air taken into the cleaner case 11 from the air inlet 12b passes through the cleaner element 30a and is purified.
The material of the cleaner element 30a and the size of the mesh are not limited, and are appropriately set according to the use conditions.

(Configuration of lower case)
As shown in FIG. 3, the lower case 13 is formed with a substantially rectangular bottom plate 13 a in plan view and an outer peripheral wall portion 13 b that is raised over the entire outer periphery of the upper surface of the bottom plate 13 a. The outer peripheral wall portion 13b of the lower case 13 has a shape in which the outer peripheral wall portion 12a of the upper case 12 can be fitted.
Further, as shown in FIG. 5, a locking groove 13 f that is recessed inward is formed on the outer peripheral side surface of the lower end portion of the outer peripheral wall portion 13 b of the lower case 13.
Then, the outer peripheral wall portion 12 b of the upper case 12 is fitted on the outer peripheral wall portion 13 b of the lower case 13, and the locking projection 12 d formed on the outer peripheral wall portion 12 a of the upper case 12 is attached to the outer peripheral wall portion 13 b of the lower case 13. By engaging with the formed engaging groove 13f, the upper case 12 and the lower case 13 can be fitted together to form the cleaner case 11.

Further, as shown in FIG. 3, the bottom plate 13a of the lower case 13 has a plurality of air inlets 13d... That are configured to take in external air from the air inlets 13d. .
As shown in FIG. 5, a nylon mesh cleaner element 30 b is pressure-bonded to the lower surface of the lower case 13 so as to cover each intake port 13 d (see FIG. 3). As a result, the air taken into the cleaner case 11 passes through the cleaner element 30b and is purified.
In addition, the cleaner element 30b attached to the lower case 13 is not limited in the material and the mesh size like the cleaner element 30a in the upper case 12, and is appropriately set according to use conditions. is there.

Further, an exhaust port 13c for supplying the air taken into the cleaner case 11 through the cleaner elements 30a and 30b to the intake passage E1 of the engine E is opened at the rear center portion of the bottom plate 13a of the lower case 13. is doing.
Further, a plurality of rectifying plates 13e formed radially from the opening edge of the exhaust port 13c to the inner peripheral surface of the outer peripheral wall portion 13b are arranged radially on the upper surface of the bottom plate 13a of the lower case 13. This baffle plate 13e is a member for guiding the air taken into the cleaner case 11 to the exhaust port 13c.
Thus, since the air taken into the cleaner case 11 is guided to the exhaust port 13c by the respective rectifying plates 13e ..., the exhaust port 13c is extended from the extending direction (upward direction) of the exhaust port 13c. In addition to taking in air, the air guided by the respective rectifying plates 13e... From the periphery of the exhaust port 13c can be taken into the exhaust port 13c. Further, a reflecting plate 12e is provided at a position facing the exhaust port 13c, and air is taken into the exhaust port 13c from around the reflecting plate 12e.
Therefore, in the air cleaner 10 of the present embodiment, since the range in which air is taken into the cleaner case 11 is wide, air is introduced into the cleaner case 11 from a wide range of the cleaner elements 30a and 30b attached to the upper case 12 and the lower case 13. Will be adopted.

(Composition of connecting part)
As shown in FIG. 5, the upper opening 21 communicates with the exhaust port 13 c of the lower case 13, and the lower opening 22 communicates with the intake passage E <b> 1 of the engine E. Is formed. The flow path 23 of the connecting portion 20 is bent 90 degrees, the upper opening 21 is opened upward, and the lower opening 22 is opened forward.
The connecting portion 20 is formed integrally with the lower case 13, and the lower case 13 and the connecting portion 20 are formed as one continuous part.

  Further, as shown in FIG. 4, flange portions 24, 24 are formed on both sides in the width direction on the outer peripheral portion of the lower opening 22 (see FIG. 5). The bolt inserted through the hole 24a formed in the flange portion 24 is screwed into a screw hole (not shown) formed in the outer end portion of the intake passage E1 of the engine E, as shown in FIG. As described above, the air cleaner 10 can be attached to the engine E in a state where the flow path 23 of the air cleaner 10 and the intake passage E1 of the engine E are in communication with each other.

Further, as shown in FIG. 5, an extended space 25 protruding outward is formed at a position facing the lower opening 22 on the inner peripheral surface of the flow path 23 of the connecting portion 20.
Here, the position facing the lower opening 22 on the inner peripheral surface of the flow path 23 is a position facing the outside of the lower opening 22, and the lower opening 22 from the intake passage E 1 of the engine E This is the position where the fuel gas that has passed through and entered the flow path 23 is sprayed.

Here, the flow of the fuel gas when the fuel gas is blown back from the engine will be described. In FIG. 5, the flow of fuel gas is indicated by arrows.
First, the fuel gas enters the flow path 23 from the lower opening 22 and is blown into the expansion space 25.
Then, the fuel gas blown into the expansion space 25 is returned toward the lower opening 22. A part of the gas flows toward the upper opening 22 and flows back into the cleaner case 11 from the exhaust port 13c, but is reflected by the reflection plate 12e provided at a position facing the exhaust port 13c.
At this time, the rib 12f is erected on the outer peripheral edge of the lower surface of the reflecting plate 12e, and the fuel gas reflected by the reflecting plate 12e is suppressed from spreading in the lateral direction (plane direction) by the rib 12f. The fuel gas is returned to the exhaust port 13 c without being scattered in the cleaner case 11.

[Operation effect of air cleaner]
According to the air cleaner 10 of the present embodiment, as shown in FIG. 5, the connecting portion 20 that is in communication with the exhaust port 13 c of the cleaner case 11 and in which the flow path 23 that is in communication with the intake passage E <b> 1 of the engine E is formed. Since it is formed integrally with the cleaner case 11 and no joint is formed at the connecting portion of the cleaner case 11 and the connecting portion 20 or the connecting portion 20, dust such as chips generated during cutting work enters the connecting portion 20. Can be prevented, and the purification performance of the air supplied to the engine E can be improved.

  Further, since the cleaner case 11 and the connecting portion 20 are integrally formed, the number of parts of the air cleaner 10 is reduced, so that the manufacturing cost of the air cleaner 10 can be reduced and the air cleaner 10 can be easily assembled. .

In addition, an expansion space 25 protruding outward is formed at a position facing the lower opening 22 on the inner peripheral surface of the flow path 23 of the connecting portion 20, and fuel gas is blown back from the engine E. Sometimes, the fuel gas is blown into the expansion space 25 from the lower opening 22, so that the fuel gas can be prevented from being directly blown into the cleaner case 11.
Further, the fuel gas blown into the expansion space 25 is returned toward the lower opening 22, and part of the fuel gas flows toward the upper opening 21, and backflows into the cleaner case 11 from the exhaust port 13 c. However, since the reflecting plate 12e is provided at a position facing the exhaust port 13c of the cleaner case 11, the fuel gas flowing back into the cleaner case 11 is reflected by the reflecting plate 12e and is reflected by the exhaust port 13c. Will be returned to.
Thus, in the air cleaner 10 of the present embodiment, it is possible to prevent deterioration of the cleaner elements 30a and 30b due to the adhesion of fuel and oil contained in the fuel gas blown back from the engine E.
In the reflecting plate 12e, ribs 12f are erected on the outer peripheral edge of the lower surface facing the exhaust port 13c. When the fuel gas blown back from the engine E is reflected by the reflecting plate 12e, the fuel gas is Since the lateral extension is suppressed by the ribs 12f, the fuel gas can be returned to the exhaust port 13c without being scattered in the cleaner case 11.

Further, since the air taken into the cleaner case 11 is guided to the exhaust port 13c by the rectifying plate 13e, not only the air is taken in from the extension direction (upward direction) of the exhaust port 13c but also rectified from the periphery of the exhaust port 13c. The air guided to the plate 13e can be taken into the exhaust port 13c.
Further, a reflecting plate 12e is provided at a position facing the exhaust port 13c, and air is taken into the exhaust port 13c from around the reflecting plate 12e.
Thereby, the range in which air is taken into the cleaner case 11 can be expanded, and air is taken in from a wide range of the cleaner elements 30a and 30b. Therefore, the flow rate per unit area of the air passing through the cleaner elements 30a and 30b is reduced. The maintenance period of the cleaner elements 30a and 30b can be lengthened.

[Modification]
The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention.
For example, in this embodiment, as shown in FIG. 3, the cleaner case 11 is divided into an upper case 12 and a lower case 13, but the cleaner case 11 may be composed of one part, and the configuration is limited. It is not something.

  Further, the configuration of the opening area and the number of the intake port 12b of the upper case 12 and the intake port 13d of the lower case 13 is not limited, and is appropriately set in consideration of the intake efficiency.

  Moreover, in this embodiment, as shown in FIG. 1, although the case where the air cleaner 10 of this invention is applied to the chain saw 1 is demonstrated as an example, the working machine which can apply the air cleaner 10 of this invention is limited. It can be applied to various working machines such as brush cutters and blowers.

It is the perspective view which looked at the chain saw main body of this embodiment from diagonally upward. It is the perspective view which looked at the air cleaner of this embodiment from diagonally upward. It is the disassembled perspective view which showed the air cleaner of this embodiment. It is the figure which looked at the air cleaner of this embodiment from back. It is the figure which showed the air cleaner of this embodiment, and is AA sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chain saw 10 Air cleaner 11 Cleaner case 12 Upper case 12b Inlet 12c Supporting member 12d Locking protrusion 12e Reflector 12f Rib 13 Lower case 13a Bottom plate 13c Exhaust port 13e Rectifier plate 13d Inlet port 13f Opening part 21 Connecting part 21 Upper part 22 Lower opening 23 Flow path 25 Expansion space 30a Cleaner element 30b Cleaner element E Engine E1 Intake passage

Claims (4)

An air cleaner for purifying air supplied to an engine,
A cleaner case to which a cleaner element for purifying air is attached;
The cleaner case has an intake port for taking in air from the outside, and an exhaust port for supplying air that has passed through the cleaner element to the engine.
One opening portion communicates with the exhaust port of the cleaner case, and the other opening portion includes a connecting portion in which a flow path communicating with the intake passage of the engine is formed.
The cleaner case and the connecting portion are integrally formed ,
The flow path of the connecting portion is bent,
In the bent part of the flow path, an expansion space formed by recessing the inner peripheral surface of the connecting part is formed at a position facing the other opening so as to face the other opening. Air cleaner characterized by being made . The air cleaner according to claim 1 , wherein a rectifying plate is provided inside the cleaner case for guiding air taken into the cleaner case to the exhaust port. Wherein the cleaner case, an air cleaner according to claim 1 or claim 2, characterized in that the reflector is provided at a position opposed to the exhaust port. The air cleaner according to claim 3 , wherein a rib is erected on an outer peripheral edge of a surface of the reflecting plate that faces the exhaust port.

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