WO2009031710A1

WO2009031710A1 - Portable cutting tool

Info

Publication number: WO2009031710A1
Application number: PCT/JP2008/066491
Authority: WO
Inventors: Shinji Takano
Original assignee: Hitachi Koki Co., Ltd.
Priority date: 2007-09-07
Filing date: 2008-09-05
Publication date: 2009-03-12
Also published as: JP4936224B2; JP2009061737A

Abstract

There is provided a portable cutting tool (1) capable of providing excellent visibility of an inked line when blade tips of a saw blade 6 are. seen from a side • sμrf ace of the saw blade 6 facing a direction away from the housing 4.. The guide body 21 is placed outside the saw cover 5. Inside the guide body 21, the first passage 23 to blow air toward a blade tips of the side surface of the saw blade 6, the second passage 24 to blow air toward the blade tips of a side surface of the saw blade 6 facing the housing 4, and the third passage 25 to blow air toward the cutting direction in a portion close to a front end of the base 2 are formed.

Description

DESCRIPTION PORTABLE CUTTING TOOL

Technical Field The present invention relates to a portable cutting tool and more particularly to the portable cutting tool capable of blowing air from the fan for cooling a motor toward a side of saw blade.

Background Art

A portable cutting tool is equipped with a motor serving as a drive source, and a saw blade driven by the motor for cutting a work. A housing is located at a position facing one side surface of the saw blade and the motor is built-in in the housing. Moreover, a fan for cooling the motor is provided in the housing, and the fan is driven rotationally by the motor. A saw cover is connected to the housing, and the saw cover is placed close to a row of the saw blade and covers partially the row of the saw blade. Also, the portable cutting tool is provided with a base which supports the saw cover rotatably and is in touch with the work, and an opening portion to let the saw blade be extruded toward the work is formed in the base.

In the housing, an air passage is formed to introduce fan air generated by the fan toward the saw cover. Then, the fan air is introduced in the saw cover placed close to the side of the saw blade facing the housing. Then, the fan air introduced into the saw cover is blown off on the side of the saw blade facing the housing and, as a result, cut chips produced at a time of cutting work are blown off by the fan air from the working area. This improves visibility of an inked line drawn on the work (See Patent Literature 1: Japanese Patent Publication No. 3748073). Disclosure of Invention

According to the portable cutting tool disclosed in Patent Literature 1, the visibility of an inked line existing in close to blade tips of the saw blade is improved when seen from the direction from the housing toward the saw cover. However, at an opposite side of the saw blade, the saw blade blocks the fan air and it causes a difficulty in fully removing the cut chips existing vicinity of the tips of the saw blade on the side facing a direction away from the housing. Therefore, sufficient visibility of an inked line cannot be obtained. An object of the present invention is to provide a portable cutting tool providing excellent visibility of an inked line when blade tips of saw blade are seen from the side of the saw blade facing away from the housing.

Another object of the present invention is to provide the portable cutting tool having a blower function of blowing off cut chips staying on the work at the front, which is forward in the cutting direction in which the base moves, of the base, by blowing fan air in the cutting direction to the proximity to the end of the base, and a function of blowing the fan air on sides of the saw blade and in the vicinity of the blade tips of the saw blade to thereby, enhancing the visibility of an inked line and thus improving the working efficiency.

To achieve the above objects, the portable cutting tool of the present invention is so configured to comprise a motor; a saw blade driven by the motor for cutting a work; a fan driven rotationally by the motor; a housing which is placed in a manner to face one side of the saw blade and in which the motor and the fan are housed, a saw cover covering a part of series of blades of the saw blade connected to the housing, a base having one surface being in touch with the work and another surface which is opposite to the one surface and to which at least one of the saw cover and housing is attached and an opening which is formed on the base so as to pass through the one surface to the another surface so that the saw blade is protrudable therefrom, an air passage formed in the housing which guides fan air generated by rotation of the fan toward the saw cover direction, and a guide body which is mounted on the saw cover, which communicates with the air passage and in which a first passage to blow the fan air guided from the air passage toward the another side of the saw blade is formed.

It is preferable that the first passage is constructed so as to supply the fan air to portions surrounding blade tips of the saw blade existing close to the opening on the one surface of the base in a direction toward the one surface from the another surface of the base.

It is preferable that a second passage to blow the fan air toward a surface of the one side of the saw blade is further formed in the guide body.

It is preferable that a third passage to blow the fan air to portions surrounding an end of the base facing a cutting direction of the portable cutting tool toward the cutting direction is further formed.

It is preferable that at least a part of the air passage is formed between the motor and the housing.

It is preferable that illuminating surfaces are placed between a side of the saw cover facing the another side of the saw blade and the guide body, the illuminating surfaces emit light to blade tips existing on the another side of the saw blade and portions surrounding the blade tips, and wire rods to emit light from the illuminating surfaces are held by the guide body in the first passage along an inner surface of the guide body. Also, it is preferable that an illuminating body is disposed between a side of the saw cover facing the one side of the saw blade and the guide body, and the illuminating body emits light to blade tips existing on the one side of the saw blade and portions surrounding the blade tips and the illuminating body is held by the guide body. Furthermore, it is preferable that the illuminating body is placed in the second passage.

A portable cutting tool of the present invention is configured to comprise a motor, a saw blade driven by the motor for cutting a work; a fan driven rotationally by the motor; a housing which is placed in a manner to face one side of the saw blade and in which the motor and the fan are housed, a saw cover covering a part of series of blades of the saw blade connected to the housing, a base having one surface being in touch with the work and another surface which is opposite to the one surface and to which at least one of the saw cover and housing is attached and an opening which passes through the one surface to other surface is formed in the base so that the saw blade is protrudable therefrom, an air passage formed in the housing which guides fan air generated by rotation of the fan toward the saw cover direction; and a guide body being communicated with the air passage and being disposed in the saw cover, in which a blower passage to blow the fan air to portions surrounding an end of the base facing a cutting direction of the portable cutting tool toward the cutting direction and a blade tip passage to blow the fan air toward a side surface of the blade tips of the saw blade are formed.

It is preferable that the blade tip passage is a first blade tip passage to blow the fan air toward the another side of the saw blade. Also, it is preferable that the first blade tip passage is constructed to supply the fan air to portions surrounding blade tips of the saw blade existing close to the opening on the one surface of the base in a direction toward the one surface from the another surface of the base.

It is preferable that the blade tip passage comprises the first blade tip passage to blow the fan air toward a surface of the another side of the saw blade and a second blade tip passage to blow the fan air toward a surface of the one side of the saw blade.

It is preferable that illuminating surfaces are disposed between a side of the saw cover facing the another side of the saw blade and the guide body, and light is emitted from the illuminating surfaces to blade tips existing on the another side of the saw blade and portions surrounding the blade tips, and wire rods to the illuminating surfaces for emitting light are held by the guide body in the first blade tip passage along an inner surface of the guide body.

It is preferable that an illuminating body is disposed between a side of the saw cover facing the one side of the saw blade and the guide body, and the illuminating body emits light to the blade tips existing on the one side of the saw blade and portions surrounding the blade tips and the illuminating body is held by the guide body.

It is preferable that the illuminating body is disposed in the second blade tip passage. According to the portable cutting tool of the present invention, since cut chips existing in portions close to blade tips on a side of the saw blade facing a direction away from the motor are removed by fan air, visibility of a cut portion and an inked line can be improved when a worker looks at the cut portion or inked line existing in portions close to blade tips from a side of the saw blade facing a direction away from the motor. According to the portable cutting tool of the present invention, fan air is blown toward a cutting direction in portions close to an end of the base facing the cutting direction of the portable cutting tool to remove cut chips staying forward in the cutting direction and fan air is also blown in portions surrounding the blade tips of the saw blade to remove cut chips on the inked line or cut chips existing in portions close to the blade tips, thereby providing excellent visibility of an inked line to improve efficiency of cutting work.

Brief Description of Drawings

FIG.l is a top view showing the portable cutting tool of an embodiment of the present invention.

FIG. 2 is a side view showing the portable cutting tool of the embodiment of the present invention.

FIG. 3 is an enlarged view showing the region A of FIG. 2.

FIG. 4 is a cross-sectional view of the portable cutting tool of FIG. 3 taken along the line IV-IV.

FIG. 5 is a cross-sectional view of the portable cutting tool of FIG. 3 taken along the line V-V.

FIG. 6 is a diagram showing a saw blade and light for illuminating blade tips when seen from an arrow VI of FIG. 5.

Best Mode for Carrying Out the Invention

Hereinafter, the portable cutting tool of an embodiment of the present invention is described by referring to drawings. FIGS. 1 and 2 show the entire configurations of the portable cutting tool 1 and, in these drawings, the right side shows a cutting direction or a forward portion of the portable cutting tool in the cutting direction and the left side shows a backward portion of the portable cutting tool in the cutting direction. The portable cutting tool 1 includes a base 2 which comes in touch with a work at a time of cutting work and a main body of a circular saw 3 disposed on a surface opposite to a surface of the base 2 being in touch with the work and mounted rotatably to the base 2. As shown in FIG. 2, the base 2 is plate-shaped and one surface of the base 2 is in touch with the work W and slides thereon. Also, an opening portion 2a is formed in the center portion of the base 2, and the opening portion 2a penetrates the surface being in touch with the work W to a surface opposite to the surface being in touch therewith. The saw blade 6 is protrudable from the base 2 through the opening portion 2a. Further, in a portion of the base 2 close to an end placed forward in the cutting direction, a rotatable support portion 11 is provided to support the main body of the circular saw 3 rotatably in relative to the base 2. The rotatable support portion 11 has a rotatable pin 12 which extends in parallel to a circular saw shaft 6A.

The housing 4 and saw cover 5 make up an outer portion of the main body of the circular saw 3. The housing 4 is disposed in a manner facing toward one side surface of the saw blade 6. In an inner portion of the housing 4, a motor 7 for rotating the saw blade 6 and an unillustrated power transmission mechanism to transfer the rotation of the motor 7 to the saw blade 6 are embedded. Also, a handle 8 is formed in a crest portion of the housing 4. The saw cover 5 is configured to cover the upper half of the series of blades of the saw blade 6 and is mounted integrally on one end of the housing 4. An end of the saw cover 5 placed forward in the cutting direction is connected to the rotatable pin 12 of the rotatable support portion 11 which enables a change in an amount of protrusion of the saw blade 6 from the base 2. Further, a fixing releasing mechanism 13 is displaced between the base 2 and the main body of the circular saw 3 at a backward end of the saw cover 5 in the cutting direction, and the fixing releasing mechanism 13 fixes the position of rotatably moved main body of the circular saw 3 and releases the fixing. Moreover, the rotatable support portion 11 has a mechanism to move the main body of the circular saw 3 in a manner to be slanted toward the base 2, that is, a slanting moving mechanism to slant the main body of the circular saw 3 to a direction parallel to the base 2 and orthogonal to the rotatable pin 12 and to fix the slanted position and to release the fixing of the position. Detailed descriptions of the slanting moving mechanism are provided in Japanese Patent Publication No. 388165.

Furthermore, a safety cover 9 for covering the lower half of the saw blade 6 while the portable cutting tool 1 is not used is provided, and the safety cover 9 is mounted rotatably about a center of the rotation shaft 6 A of the saw blade 6. The safety cover 9 is provided with a safety cover lever 10 which is manipulated by using a fingertip to maintain the rotation position. When the work W is to be cut from its back end toward its front, the safety cover 9 rotates automatically to expose the series of blades of lower portion of the saw blade 6. Moreover, when the saw blade 6 needs to be moved from the upper portion to the lower portion of the work W₅ for example, in cutting to form a window-like opening , a worker maintains an open state of the safety cover 9 by laying his/her fingertip on the safety cover lever 10.

An air passage 4a extending in the direction of the saw cover 5 is formed between the housing 4 and the motor 7. Also, a fan 20 is mounted on the rotation shaft of the motor 7, and the fan 20 is driven rotationally by the motor 7. The fan 20 is attached in the housing 4 coaxially with the rotation shaft of the motor 7. The fan 20 introduces air into the housing 4 from an unillustrated inhalation port formed in the housing 4. The introduced air passes through the air passage 4a. During the passing, a heat exchange between air existing on the side surface of the motor 7 forming the air passage 4a and the introduced air is performed, thereby cooling the motor 7.

A guide body 21 is mounted on an outside of the saw cover 5. The guide body 21, as shown in FIG. 4, is made up of the first guide body 21 A disposed on the motor 7 side and the second guide body 21B disposed on the side facing away from the motor 7. That is, the first guide body 21 A faces the side of the saw blade 6 toward the motor 7 and the second guide body 21B faces the side surface of the saw blade 6 in the direction away from the motor 7. The first guide body 21 A is coupled to the second guide body 2 IB in a portion close to the position where the first guide body 21 A and the second guide body 21B straddles the series of blades of the saw blade 6. As shown in FIG. 4, an introduction passage 22 which communicates with the air passage 4a, the first passage 23 (first blade tip passage), and the third passage 25 (blower passage) are formed between the saw cover 5 and guide body 21. The second passage 24 (second blade tip passage) is formed so as to pass through the saw cover 5 and first guide body 21 A. As shown in FIG. 4, the first passage 23 is communicated with the introduction passage 22. The first passage 23 forms an approximately U-shaped cross section together with the first guide body 21 A, second guide body 21B₅ and saw cover 5 and extends from a side surface of the blade tip of the saw blade 6 on the motor 7 side along a side surface of the blade tip of the saw blade 6 facing the direction away from the motor 7. The end portion of the opening of the first passage 23, as shown in FIG. 5, opens toward blade tips existing on a side surface of the saw blade 6 facing the direction away from the motor 7. More specifically, as shown by the arrow a2 in FIG. 5, when it is defined that the saw cover 8 is placed in the upward direction relative to the base 2, the first passage 23 is so configured that fan air is supplied by the second guide body 2 IB from a slanted upward direction to a portion close to the intersection between an imaginary plane containing a bottom of the base 2 and an outer radius on a side surface of the saw blade 6 facing the direction away from the motor 7. In other words, the first passage 23 is so configured that fan air is supplied in a slanting manner from the upward to downward direction to a portion close to the opening portion 2a of the bottom of the base 2 and close to a blade tip on a side surface of the saw blade 6 facing the direction away from the motor 7.

As shown in FIGS. 4 and 5, the second passage 24 is formed in a manner being branched from the portion on the motor side of the first passage 23. The end of the second passage 24 opens toward a portion close to the blade tips of the saw blade 6 on the motor 7 side. More specifically, as shown by the arrow a3 in FIG. 5, when it is defined that the saw cover 8 is placed in the upward direction relative to the base 2, the second passage 24 is so configured that fan air is supplied by the first guide body 21 A from a slanted upward direction to a portion close to the intersection between an imaginary plane containing the bottom of the base 2 and an outer radius on a side surface of the saw blade 6 facing toward the motor 7. In other words, the second passage 24 is so configured that fan air is supplied in a slanting manner from the upward to downward direction to a portion close to the opening portion 2a of the bottom of the base 2 and close to a blade tip on a side surface of the saw blade 6 facing the direction toward the motor 7.

Further, as shown in FIGS. 3 and 4, the third passage 25 is formed in a manner being branched from the first passage 23 in a portion close to the connecting region between the first guide body 21 A and the second guide body 2 IB. An end of the third passage 25 is positioned in a portion closed to an end of the base facing 2 forward in the cutting direction and opens toward the cutting direction.

As shown in FIGS. 4 and 6, a pair of lights 26 is mounted in the first guide body 2 IA, and the lights 26 using LED (Light Emitting Diodes) or the like illuminate portions surrounding the blade tips of the saw blade 6 from the motor 7 side. The pair of the lights 26 for illuminating the blade tips is arranged side by side along the cutting direction of the portable cutting tool 1. Also, a power source 27 connected to the lights 26 are disposed in the first guide body 21 to supply power to the lights 26 for illuminating the blade tips. The lights 26 for illuminating the blade tip are connected to the power source 27 via an unillustrated code. That is, the power source 27 and the pair of the lights 26 for illuminating the blade tips are arranged in the first passage 23 in the first guide body 21 A. The light 28 using LED or the like for illuminating the blade tips is mounted in the second guide body 2 IB, which illuminates a portion surrounding the blade tip of the saw blade 6 from a side facing the direction away from the motor 7. Further, a code 29 for supplying power from the power source 27 to the light 28 for illuminating the blade tips is held in the first passage 23 along inside faces of the first guide body 21 A and second guide body 2 IB.

When the motor 7 is driven to cut the work W, the saw blade 6 and the fan 20 are rotated. Then, by the rotation of the fan 20, air is flown along the air passage 4a to cool the motor 7. The air flowing through the air passage 4a passes through the fan 20 and, as shown by the arrow al in FIG. 4, is guided into the introduction passage 22 formed on the inner side of the first guide body 2 IA. Then, the air guided into the introduction passage 22, as shown by an arrow a5 in FIG. 4, is guided further into the first passage 23. Part of the air guided into the first passage 23 flows into the second passage 24 and a part of another air flows into the third passage 25 as shown by the arrow a4 in FIG. 4. Moreover, the remaining air flows along the first passage 23 from the first guide body 21 A to the second guide body 2 IB of the first passage 23 and flows into the end of the opening of the first passage 23. The air having flowed along the first passage 23, as shown by the arrow a2 in FIG. 4 or 5, blows out toward the blade tips on the side surface of the saw blade 6 facing the direction away from the motor 7 and blows off cut chips existing on a side of the saw blade 6 facing the direction away from the motor 7. Therefore, a worker can easily see visually an inked line when looking at cut portions from a side of the saw blade 6 facing the direction away from the motor 7. Further, cut chips scattering on the worker side can be blocked by the air flow a2. Also, as shown by the arrow a2 in FIG. 5, when it is defined that the saw cover 8 is placed in the upward direction relative to the base 2, the first passage 23 is so configured that fan air is supplied by the second guide body 2 IB from a slanted upward direction to a portion close to the intersection between an imaginary plane containing a bottom of the base 2 and an outer radius on a side surface of the saw blade 6 facing the direction away from the motor 7. In other words, the first passage 23 is so configured that fan air is supplied in a slanting manner from the upward to a downward direction to a portion close to the opening portion 2a of the bottom of the base 2 and close to the blade tips on a side surface of the saw blade 6 facing the direction away from the motor 7. That is, the air-blowing portion of the first passage 23 of the second guide body 21B₃ in order to blow out an air flow from a slanted upward direction in a portion close to the cut portion, is arranged apart upwardly by a predetermined distance from a portion of the base 2 or saw blade 6 close to the cut portion of the work W. Also, as shown in FIG. 5, the outer shape of a portion close to the air-blowing portion of the first passage 23 of the second guide body 21B is inclined toward a portion close to the cut portion in the same direction as that of the air flow a2. Therefore, when a worker checks a portion on a side of the saw blade 6 facing the direction away from the motor 7, it prevents the portion making up the first passage 23 of the second guide body 21B from becoming an obstruction to visual inspection and serves to improve the visibility.

Moreover, since the blade tips of the saw blade 6 on a side facing the direction away from the motor 7 are illuminated by the light 28 for illuminating the blade tips, the visibility in a portion close to the cut portion of the work W is further improved. Moreover, the first and second guide bodies 21 A and 21B serve as a holding member to hold the code 29 and, therefore, the number of parts can be reduced. Also, since the power source 27 is mounted in the first passage 23, by the air flow shown by the arrow a5 in FIG. 4, the power source 27 can be cooled. Further, since the light 28 for illuminating the blade tips is placed in the first passage 23, cut chips adhering to the light 28 for illuminating the blade tips can be removed by the air flow shown by the arrow a2 in FIG. 4.

Next, the air flowed into the second passage 24 is blown out to a side surface of the blade tips of the saw blade 6 on the motor 7 side as shown by the arrow a3 in FIG. 5. As a result, it is possible to easily remove cut chips around the blade tips on a side of the saw blade 6 facing toward the motor 7. Also, cut chips scattering on the worker side can be blocked by the air flow a3. Further, as shown by the arrow a3 in FIG. 5, when it is defined that the saw cover 8 is placed in the upward direction relative to the base 2, the second passage 24 is so configured that fan air is supplied by the first guide body 21 A from a slanted upward direction to a portion close to the intersection between an imaginary plane containing a bottom of the base 2 and an outer radius on a side of the saw blade 6 facing toward the motor 7. In other words, the second passage 24 is so configured that fan air is supplied in a slanting manner from the upward to downward direction to a portion close to the opening portion 2a of the bottom of the base 2 and close to a blade tips on a side surface of the saw blade 6 facing the direction toward the motor 7. That is, the air-blowing portion of the second passage 24 of the first guide body 21 A, in order to blow out an air flow from a slanted upward direction in a portion close to the cut portion, is arranged apart upwardly by a predetermined distance from a portion of the base 2 or saw blade 6 close to the cut portion of the work W. Therefore, when a worker checks a portion on a side of the saw blade 6 facing the motor 7, it prevents the portion making up the second passage 24 of the first guide body 21 A from becoming an obstruction to visual inspection and improves the visibility. Further, since the pair of the lights 26 for illuminating the blade tips is placed in the second passage 24, cut chips adhering to the pair of the lights 26 for illuminating the blade tips can be removed by the air flowing through the second passage 24. Therefore, the pair of lights 26 for illumination the blade tips can illuminate the blade tips on the motor 7 side without being disturbed by the cut chips, thus enabling the improvement of visibility of portions close to the cut portion of the work W.

On the other hand, the air having flowed into the third passage 25, as shown by the arrow a4 in FIG. 3, blows out toward the cutting direction in a portion close to a front end of the base 2. As a result, cut chips existing ahead of the base 2 in the cutting direction can be removed and the inked line can be clearly checked, thereby improving the visibility in portions close to the cut portion of the work W.

It is understood that the present invention is not limited to the exemplary embodiment described above and various changes are possible without departing from the scope of the present invention. For example, in the portable cutting tool 1 of the present embodiment, the saw cover 5 is connected to the base 2 rotatably, however, the housing 4 may be connected to the base 2 rotatably.

Also, instead of the light 28 for illuminating the blade tips and the code 29 of the present embodiment, an optical fiber may be used. In this case, the end face of the optical fiber acts as the optical emitting end and is positioned in the position of the light 28 for illuminating the blade tips and the optical fiber itself is disposed in the position of the code

29.

Moreover, in the above embodiment, the fan air is discharged to three directions, that is, directions toward both the sides of the saw blade 6 and direction to the end of the base 2, however, the fan air may be discharged to any place so long as cut chips in portions surrounding the blade tip can be blown off. That is, the fan air may be discharged only to the portion facing the direction away from the motor 7 or may be discharged to at least one of the ends of the base 2 or the saw blade 6. Furthermore, the fan air may be discharged not only to the base end and base side surface but also to portions close to the blade tips.

Various embodiments and changes may be made thereunto without departing from the broad spirit and scope of the invention. The above-described embodiment are intended to illustrate the present invention, not to limit the scope of the present invention. The scope of the present invention is shown by the attached claims rather than the embodiment. Various modifications made within the meaning of an equivalent of the claims of the invention and within the claims are to be regarded to be in the scope of the present invention.

This application is based on Japanese Patent Application No. 2007-233385 filed on September 7, 2007. Its specification, claims, drawings and summary are incorporated herein by reference in its entirety.

Claims

1. A portable cutting tool comprising: a motor; a saw blade driven by the motor for cutting a work; a fan driven rotationally by the motor; a housing which is placed in a manner to face one side of the saw blade and in which the motor and the fan are housed; a saw cover covering a part of series of blades of the saw blade connected to the housing; a base having one surface being in touch with the work and another surface which is opposite to the one surface and to which at least one of the saw cover and housing is attached, and an opening which is formed so as to pass through the one surface to the another surface in the base so that the saw blade is protrudable therefrom; an air passage formed in the housing which guides fan air generated by rotation of the fan toward the saw cover direction; and a guide body mounted on the saw cover, communicating with the air passage, in which a first passage to blow the fan air guided from the air passage toward another side of the saw blade is formed.

2. The portable cutting tool according to claim 1 , wherein the first passage is constructed so as to supply the fan air to portions surrounding blade tips of the saw blade existing close to the opening on the one surface of the base in a direction toward the one surface from the another surface of the base.

3. The portable cutting tool according to claim 1, wherein a second passage to blow the fan air toward a surface of the one side of the saw blade is further formed in the guide body.

4. The portable cutting tool according to claim 1 or claim 3, wherein a third passage to blow the fan air to portions surrounding an end of the base facing a cutting direction of the portable cutting tool toward the cutting direction is further formed.

5. The portable cutting tool according to claim 1, wherein at least a part of the air passage is formed between the motor and the housing.

6. The portable cutting tool according to claim 1 or 3, wherein illuminating surfaces are placed between a side of the saw cover facing the another side of the saw blade and the guide body, illuminating surfaces emit light to blade tips existing on the another side of the saw blade and portions surrounding the blade tips, and wire rods to emit light from the illuminating surfaces are held by the guide body in the first passage along an inner surface of the guide body.

7. The portable cutting tool according to claim 6, wherein an illuminating body is disposed between a side of the saw cover facing the one side of the saw blade and the guide body, and the illuminating body emits light to the blade tips existing on the one side of the saw blade and portions surrounding the blade tips and the illuminating body is held by the guide body.

8. The portable cutting tool according to claim 7, wherein the illuminating body is placed in the second passage.

9. A portable cutting tool comprising: a motor; a saw blade driven by the motor for cutting a work; a fan driven rotationally by the motor; a housing which is placed in a manner to face one side of the saw blade and in which the motor and the fan are housed; a saw cover covering a part of series of blades of the saw blade connected to the housing; a base having one surface of which is in touch with the work and another surface positioned opposite to the one surface and at least one of the saw cover and housing is attached thereto, and an opening which passes through the one surface to the another surface is formed in the base so that the saw blade is protrudable therefrom; an air passage formed in the housing which guides fan air generated by rotation of the fan toward the saw cover direction; and a guide body being communicated with the air passage and being disposed in the saw cover, in which a blower passage to blow the fan air to portions surrounding an end of the base facing a cutting direction of the portable cutting tool toward the cutting direction and a blade tip passage to blow the fan air toward a side surface of the blade tips of the saw blade are formed.

10. The portable cutting tool according to claim 9, wherein the blade tip passage is a first blade tip passage to blow the fan air toward the another side of the saw blade.

11. The portable cutting tool according to claim 10, wherein the first blade tip passage is constructed to supply the fan air to portions surrounding blade tips of the saw blade existing close to the opening on the one surface of the base in a direction toward the one surface from the another surface of the base.

12. The portable cutting tool according to claim 9, wherein the blade tip passage comprises the first blade tip passage to blow the fan air toward a surface of the another side of the saw blade and a second blade tip passage to blow the fan air toward a surface of the one side of the saw blade.

13. The portable cutting tool according to claim 12, wherein illuminating surfaces are disposed between a side of the saw cover facing the another side of the saw blade and the guide body, and light is emitted from the illuminating surfaces to blade tips existing on the another side of the saw blade and portions surrounding the blade tips, and wire rods to the illuminating surfaces for emitting light are held by the guide body in the first blade tip passage along an inner surface of the guide body.

14. The portable cutting tool according to claim 13, wherein an illuminating body is disposed between a side of the saw cover facing the one side of the saw blade and the guide body, and the illuminating body emits light to the blade tips existing on the one side of the saw blade and portions surrounding the blade tips and the illuminating body is held by the guide body.

15. The portable cutting tool according to claim 4, wherein the illuminating body is disposed in the second blade tip passage.