Refuse-trapping cover for use in portable working machine

Abstract

There is provided a refuse-trapping cover for a portable working machine, which is capable of reducing the deterioration of the engine-cooling performance of the cooling fan that may be caused by the fibrous sawdust of a palm tree. The refuse-trapping cover includes a frame (40) having a plurality of open windows (40a-40j) and attached to the outer casing (20) of a chain saw (1) to thereby cover the air inlet slits (22), and a mesh member (50) integrally fixed to the frame (40) to thereby cover open windows (40a-40j). The frame (40) is constructed to have predetermined dimension and configuration, and the mesh member (50) is fixed to a predetermined location of the frame (40) to thereby provide a sufficient space (S) between the mesh member (50) and the outer casing (20) to avoid the mesh member (50) from being adsorbed onto the outer casing (20).

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a perspective view illustrating one example of the refuse-trapping cover for a portable working machine according to the present invention;

FIG. 2 is a perspective view illustrating a state wherein the refuse-trapping cover shown in FIG. 1 is mounted on a chain saw;

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 2;

FIG. 4 is a cross-sectional view of another example of the refuse-trapping cover according to the present invention, the cross-sectional view corresponding to that taken along the line III-III of FIG. 2; and

FIG. 5 is a perspective view showing a chain saw representing one example of a portable working machine, to which the refuse-trapping cover of the present invention can be applied.

DETAILED DESCRIPTION OF THE INVENTION

Next, one embodiment of the refuse-trapping cover which is useful in a portable working machine according to the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view illustrating one example of the refuse-trapping cover for a portable working machine according to the present invention.

The refuse-trapping cover 30 according to this example shown in FIG. 1 is designed to be used in a chain saw 1 which is illustrated in FIG. 5 described above. As shown in FIG. 2, this refuse-trapping cover 30 includes a dish-like frame 40 (see also FIG. 3) attached to an outer casing 20 of the chain saw 1 so as to cover all of the air inlet slits 22, and a mesh member 50 made of nylon.

The frame 40 is made of a resilient elastic synthetic resin and provided with a plurality of open windows 40a, 40b, 40c, 40d, 40e, 40f, 40g, 40h, 40i and 40j having various configurations such as a circular, triangular or rectangular configuration. The frame 40 is also provided with handle-contacting portions 46 and 47. Further, the frame 40 is provided, at appropriate intervals, with L-shaped mounting hooks 41, 42, 43 and 44 (only the mounting hook 41 is clearly shown as a typical example in FIG. 3), which are designed to be engaged with a periphery edge portion of the air inlet slits 22.

As shown in FIG. 3 in addition to FIGS. 1 and 2, the mesh member 50 is integrally fixed to the rear surface of the frame 40 by making use of an adhesive for example so as to cover all of the open windows 40a-40j. Accordingly, the frame 40 in this embodiment is disposed on the outside (front surface side) of the mesh member 50.

Further, a grid portion of the mesh member 50 is constituted by openings each 2.0 mm² in size, thereby enabling powdery sawdust to pass therethrough while enabling fibrous sawdust to be entrapped therein.

As shown in FIG. 3, in this embodiment, the dimension and configuration (curvature) of the frame 40 are set such that a space “S” having a predetermined depth can be secured between the mesh member 50 and the outer casing 20.

The aforementioned space “S” having a predetermined depth between the mesh member 50 and the outer casing 20 may be formed, other than the aforementioned method (FIG. 3), in such a manner that, when the frame is molded, the mesh member 50 is insert-molded or integrally molded so as to permit the mesh member 50 to be sandwiched between the front surface and the rear surface of the frame 40′ as shown in FIG. 4. In this case also, the frame 40′ is partially disposed on the outside (front surface side) of the mesh member 50.

According to the refuse-trapping cover 30 for a portable working machine constructed as described in the foregoing embodiment, since the mesh member 50 is disposed to cover the air inlet slits 22 of the outer casing 20, it is possible, by means of the mesh member 50, to entrap the fibrous sawdust generated during the pruning work of a palm tree before the fibrous sawdust is sucked into the main housing 2. As a result, it is possible to reliably avoid such a situation that the fibrous sawdust enters into a space between the cylinder cover and the cooling fan to clog the space, and hence it is now possible to secure a desired engine-cooling performance (air volume).

Further, since the dimension and configuration of the frame 40 are designed so as to provide a space “S” having a predetermined depth between the mesh member 50 and the outer casing 20, it is now possible to increase an effective cooling air-sucking area as compared with the conventional structure where the mesh member is directly adhered onto the surface of the outer casing. Moreover, since this increment of effective cooling air-sucking area cannot be offset by the adsorption of the mesh member 50 onto the outer casing 20 that may be caused by the negative pressure resulting from the operation of the cooling fan, it is possible to secure a sufficient engine-cooling performance (air volume) even if the mesh member is partially clogged by the fibrous sawdust that has been trapped by the mesh member 50.

The securing of this space “S” is important because when the mesh member is adsorbed onto the outer casing, the refuse-trapping capacity of the mesh member deteriorates considerably. Therefore, in this embodiment, this space “S” is set so as to secure a depth of at least 2 mm or more.

Further, since the frame 40 is partially or entirely disposed on the outside (front surface side) of the mesh member 50, it is possible to reduce the possibilities of the mesh member 50 being damaged by an external factor such as the collision thereof with branches of tree.

Furthermore, when the mesh member 50 is formed integral with the frame 40, it is possible to secure a additional structural strength. Additionally, since the refuse-trapping cover is removably attached, through mounting hooks 41-44, to the outer casing 20, the removal of the refuse-trapping cover from the outer casing 20 for disuse of the refuse-trapping cover can be facilitated. Likewise, the attachment of the refuse-trapping cover to the outer casing 20 when it is needed to use can be easily performed, thus enhancing the convenience in the employment thereof.

Claims

1. A refuse-trapping cover for a portable working machine, the portable working machine including a main housing incorporating therein a cooling fan for an internal combustion engine, and an outer casing having a plurality of air inlet slits and disposed to cover the cooling fan, said refuse-trapping cover comprising: a frame having a plurality of open windows and attached to the outer casing to thereby cover the air inlet slits, anda mesh member integrally fixed to the frame to thereby cover said plurality of open windows.

2. The refuse-trapping cover according to claim 1, wherein the frame includes a predetermined dimension and configuration and the mesh member is fixed to a predetermined location of the frame to thereby provide at least a 2 mm space between the mesh member and the outer casing to avoid the mesh member from being adsorbed onto the outer casing.

3. The refuse-trapping cover according to claim 1, wherein the frame is at least partially located outside the mesh member.

4. The refuse-trapping cover according to claim 1, wherein the frame comprises a resilient elastic synthetic resin.

5. The refuse-trapping cover according to claim 1, wherein the mesh member is attached to the frame by insert molding or integral molding, thereby rendering the mesh member sandwiched between a front surface of the frame and a rear surface of the frame.

6. The refuse-trapping cover according to claim 1, wherein the mesh member comprises a synthetic resin or a metallic material.

7. The refuse-trapping cover according to claim 1, wherein a grid portion of the mesh member includes a plurality of openings between 0.5 mm2-3.0 mm2 in size.

8. The refuse-trapping cover according to claim 1, wherein the refuse-trapping cover is removably attached to the outer casing.

9. The refuse-trapping cover according to claim 8, wherein the frame includes a mounting hook adapted to be engaged with a peripheral edge portion of the air inlet slits.

10. A portable working machine including a main housing incorporating therein a cooling fan for an internal combustion engine;an outer casing having a plurality of air inlet slits and disposed to cover the cooling fan; anda refuse-trapping cover adapted to be attached to the outer casing, the refuse-trapping cover comprising: a frame having a plurality of open windows and adapted to be attached to the outer casing to thereby cover the air inlet slits; anda mesh member integrally fixed to the frame to thereby cover said plurality of open windows.

11. The portable working machine according to claim 10, wherein the frame includes a predetermined dimension and configuration and the mesh member is fixed to a predetermined location of the frame to thereby provide at least a 2 mm space between the mesh member and the outer casing to avoid the mesh member from being adsorbed onto the outer casing.

12. The portable working machine according to claim 10, wherein the frame is at least partially located outside the mesh member.

13. The portable working machine according to claim 10, wherein the frame comprises a resilient elastic synthetic resin.

14. The portable working machine according to claim 10, wherein the mesh member is attached to the frame by insert molding or integral molding, thereby rendering the mesh member sandwiched between a front surface of the frame and a rear surface of the frame.

15. The portable working machine according to claim 10, wherein the mesh member comprises a synthetic resin or a metallic material.

16. The portable working machine according to claim 10, wherein a grid portion of the mesh member includes a plurality of openings between 0.5 mm2-3.0 mm2 in size.

17. The portable working machine according to claim 10, wherein the refuse-trapping cover is removably attached to the outer casing.

18. The portable working machine according to claim 17, wherein the frame includes a mounting hook adapted to be engaged with a peripheral edge portion of the air inlet slits.