JP2005230977A - Cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively execute the cooling of a housing and the removal of dust by utilizing cooling air for a motor. <P>SOLUTION: An insulating cover 23 applied to a body housing 5 is extended backward so as to cover all the exhaust ports 16 of a motor housing 2. A groove part 27, which is continuous from the upper exhaust port 16 to the front end of the body housing 5, is provided to the outer face of the body housing 5. A first ventiduct 29, which leads the cooling air to the front end of the body housing 5 and discharges it forward along a blade 15, is provided between the groove part 27 and the inner face of the insulating cover 23. A second ventiduct 31, which leads the cooling air to the front end of the body housing 5 and discharges it forward from an outlet of the insulating cover 23, is provided in-between the inner face of the insulating cover 23 on the side face of the body housing 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cutting tool for performing a cutting operation with a blade protruding forward of a housing, such as a reciprocating saw.

A cutting tool such as a reciprocating saw is provided with a slider that reciprocates as the motor rotates in a metal housing, and a blade connected to the tip of the slider projects forward of the housing, and the blade cuts the material to be cut. Is possible.
In addition, it is known that an insulating cover made of rubber or the like is attached to the housing in order to ensure insulation and prevent operator discomfort due to a rise in the temperature of the housing during cutting work. In particular, in Patent Document 1, in order to improve heat insulation, an elastic member serving as an insulating cover is attached to the front cover, and a gap is provided between the front cover and a gear cover therein to cool the motor. A technique for cooling the front cover and the gear cover by flowing the working air through the gap is disclosed.

JP 2000-301411 A

By the way, at the time of cutting work, the cut part is often difficult to see due to dust generated from the material to be cut, and the operator is troublesome to interrupt the work each time to remove the dust, and the workability is not good. Therefore, it is conceivable to use the cooling air of the motor of the above technique. However, the above technique only uses a part of the cooling air of the motor and passes through a wide space inside the front cover and moves forward. Therefore, effective blowing strength cannot be obtained until dust is removed.
Note that this is also the case when the housing is provided with an illuminating body such as an LED for illuminating the cut location. When dust adheres to the illuminating body, the illuminance decreases, making it difficult to see the work location, and a dark place This leads to a decrease in workability.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a cutting tool that can effectively remove dust as well as cool the housing by utilizing the cooling air of the motor. is there.

In order to achieve the above object, according to the first aspect of the present invention, the insulating cover extends to the rear of the housing so as to cover all the exhaust ports, and on the outer surface of the housing, from the exhaust port to the front end of the housing. Provided a continuous recess, and formed a ventilation path between the recess and the inner surface of the insulating cover to guide the cooling air exhausted from the exhaust port to the front end side of the housing and exhaust it forward along the blade. It is a feature.
In addition to the object of claim 1, the invention described in claim 2 is provided with a plurality of recesses in order to prevent a turbulent flow of cooling air in the air passage and to obtain a smooth blowout. A plurality of the housings are formed so as to open independently at the front end of the housing.

According to the third aspect of the present invention, in addition to the object of the first or second aspect, in the case where the illuminating body is provided, in order to effectively prevent dust from adhering to the illuminating body, the housing and the insulating cover are provided. In between, the air for cooling is formed through the illuminating body, led to the front end side of the housing, and exhausted forward.
According to a fourth aspect of the present invention, in addition to the object of any one of the first to third aspects, in order to maintain the shape of the insulating cover and reliably guide the cooling air from the exhaust port forward, the insulating cover A plurality of protrusions are erected in the front-rear direction on at least the inner surface of the attached portion of the exhaust port.

According to the first aspect of the present invention, since all the cooling air discharged from the exhaust port is blown out to the front of the housing, in addition to the cooling of the housing, the dust of the material to be cut can be removed with sufficient blowing strength. Can be done effectively. Therefore, it is not easy to see the cut portion due to dust during work, and it is easy to use. In addition, since the air passage is formed by the recess provided on the housing side, the shape of the insulating cover is simplified and it is easy to hold, and good operability can be obtained.
According to the second aspect of the present invention, in addition to the effect of the first aspect, since the plurality of air passages are provided independently, the turbulent flow of the cooling air is less likely to occur, and the front of the housing is smooth. Can be blown out.
According to invention of Claim 3, in addition to the effect of Claim 1 or 2, in what provided the illuminating body, the adhesion of the dust to an illuminating body can be prevented effectively, and it is a dark place. Can be performed without hindrance, and the cooling effect of the lighting body can be obtained.
According to the fourth aspect of the present invention, in addition to the effect of any one of the first to third aspects, the shape of the insulating cover at the exhaust port portion is maintained without closing the exhaust port, and cooling from the exhaust port is performed. The working air can be reliably guided forward.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory side view of a reciprocating saw as an example of the cutting tool of the present invention, FIG. 2 is an explanatory plan view, FIG. 3 is an explanatory bottom view, and the reciprocating saw 1 is a front of a motor housing 2 containing a motor 3 (see FIG. 1) is connected to a main body housing 5 in which a cylindrical rod-like slider 6 that can be moved back and forth and a crank mechanism 7 that converts the rotation of the output shaft 4 of the motor 3 into the reciprocating motion of the slider 6 are connected. The main body housing 5 is a metal formed by screwing an upper housing 10 that pivotally supports the slider 6 on an upper portion of a lower housing 8 having a flange 9 through which the output shaft 4 passes and is screwed to the motor housing 2. As shown in FIG. 4 (c), the crank mechanism 7 is made of a crankshaft 11 that is pivotally supported in the vertical direction below the lower housing 8 and is integrally fixed with a bevel gear 12 that meshes with the output shaft 4. An eccentric pin 13 projecting from the upper surface of the crankshaft 11 is rotatably supported, and is composed of a slide plate 14 having a U-shaped cross section fixed orthogonally to the lower side of the slider 6.

Therefore, when the output shaft 4 rotates and the crankshaft 11 rotates through the bevel gear 12, the slide plate 14 moves back and forth with the stroke of the diameter of the movement path of the eccentric pin 13 as the eccentric pin 13 rotates. Therefore, the slider 6 reciprocates, and the cutting work by the blade 15 detachably connected to the front end of the slider 6 becomes possible. In addition, exhaust ports 16, 16... Are formed around the front end of the motor housing 2, and are taken in from an unillustrated intake port behind the motor housing 2 by the rotation of the fan 17 fixed to the output shaft 4. The cooling air for the motor 3 can be discharged from here.
18 is a guide shoe that is detachably connected to the lower surface of the lower housing 8 and protrudes forward, and is bent so as to intersect the blade 15 at right angles. The guide shoe 18 is pressed against the material to be cut to position the blade 15. Used for guidance.

  On the other hand, as shown in FIGS. 3 and 4, a pair of right and left protective ribs 19, 19 are integrally formed on the lower surface of the lower housing 8 in the front-rear direction, and the light unit 20 is interposed between the protective ribs 19, 19. Is fixed. The light unit 20 includes an LED circuit 21 having an LED as an illuminating body electrically connected to a drive circuit of the motor 3, a base plate 21a that supports the LED circuit 21 obliquely upward at the front end position, The cover plate 22 closes the lower portion of the base plate 21a. The base plate 21a and the cover plate 22 are screwed to the lower surface of the lower housing 8 so that the LED circuit 21 is fixed in a posture capable of irradiating the front of the blade 15. It has come to be. Therefore, when the motor 3 is driven, the LED circuit 21 is turned on, and the cut portion can be illuminated.

  A rubber insulating cover 23 is attached to the main body housing 5. The insulating cover 23 is attached to the main body housing 5 and is in close contact with the upper surface and the left and right side surfaces of the main body housing 5. Covers substantially the entire body housing 5 including the unit 20. As shown in FIGS. 5 and 6, a cylindrical portion 25 having a rectangular cross section through which the guide shoe 18 and the shaft support portion 24 of the slider 6 formed in the upper housing 10 pass is formed at the front end of the insulating cover 23. On the other hand, the rear end extends rearward from the exhaust port 16 in the motor housing 2 so that the rear end edge is in close contact with the peripheral surface of the motor housing 2. As shown in FIG. 7, a plurality of ridges 26, 26... In the front-rear direction are formed on the inner peripheral surface of the insulating cover 23 corresponding to the upper and left exhaust ports 16. The relief recesses 35 are respectively formed in portions corresponding to the lower exhaust ports 16.

  Further, as shown in FIGS. 2 and 4, groove portions 27, 27 serving as recesses are formed in the upper surface of the upper housing 10 in the front-rear direction so as to cut out the left and right corners. In addition, first air passages 28 and 29 for guiding cooling air from the exhaust port 16 on the upper side of the motor housing 2 to the opening of the cylindrical portion 25 of the insulating cover 23 are formed. As shown in FIG. 6, a band-shaped protective cover 30 is provided on the front surface of the shaft support 24 of the upper housing 10 so as to cover the slider 6 from the upper side to the right side. The first air passage 28 opens at the upper left side of the opening of the cylindrical portion 25, but the first air passage 29 on the right side temporarily descends along the shaft support portion 24, wraps around the protective cover 30, and is tubular. It opens at the lower right side of the opening of the part 25. That is, substantially point-symmetrical positions around the slider 6 (blade 15) are the outlets.

On the other hand, on the lower surface of the lower housing 8, the outer sides of the protective ribs 19, 19 become concave portions in the front-rear direction, and are independent from the left and right exhaust ports 16 of the motor housing 2 between the inner surface of the insulating cover 23. The 2nd ventilation path 31 and 31 which connects is formed. The front of the second air passages 31, 31 does not communicate with the tubular portion 25, communicates with outlets 32, 32 drilled in the insulating cover 23 on the left and right rear sides of the tubular portion 25, thereby An opening is provided separately from the paths 28 and 29.
Further, the inner surface of the lower portion of the insulating cover 23 is formed with protrusions 36, 36,. Thus, below the cover plate 22, a third ventilation path 33 is formed as a lighting body ventilation path that independently guides cooling air from the lower exhaust port 16 forward. Note that the front of the third air passage 33 communicates with the front of the LED circuit 21 through the protective ribs 19 and 19 after passing the cover plate 22 of the light unit 20. Since a horizontally long window 34 for irradiating the LED circuit 21 is formed at a position below the tubular portion 25 on the front surface of the insulating cover 23, the third air passage 33 is opened from the front of the LED circuit 21. 34 will open it.

  In the reciprocating saw 1 configured as described above, when the motor 3 is driven to reciprocate the slider 6 and the blade 15 as described above and the cutting operation is started, the fan 17 rotates simultaneously with the output shaft 4 and the motor housing. Cooling air is taken into 2 and discharged from the exhaust ports 16, 16... To cool the motor 3. The cooling air discharged from the exhaust port 16 is brought into contact with the inner surface of the insulating cover 23 as it is and guided forward, and enters the respective air passages separately. That is, the cooling air that has entered the first air passages 28 and 29 advances along the outer surface of the upper housing 10 and is discharged forward along the blade 15 from the opening of the tubular portion 25, so that the second air passage The cooling air that has entered 31 is discharged forward from the outlet 32, and the cooling air that has entered the third air passage 33 advances along the outer surface of the lower housing 8, passes through the front of the LED circuit 21, and passes through the window. 34 is discharged forward.

In this way, the metal main body housing 5 is effectively cooled by the cooling air passing through the air passages, and heat generation due to the reciprocating motion of the slider 6 is also suppressed. In particular, since the cooling air passing through the first air passages 28 and 29 is strongly blown forward along the blade 15, dust generated by cutting can be effectively blown off. This action of dust removal is also obtained by the cooling air blown from the outlet 32 of the second air passage 31.
On the other hand, the cooling air passing through the third ventilation path 33 blows out from the window 34 through the front of the LED circuit 21, thereby preventing dust from adhering to the LED circuit 21 and cooling the LED circuit 21. Is also possible. In addition, since it blows out forward from the window 34, the removal effect | action of the dust in a to-be-cut material is also obtained like the air for cooling from the 1st, 2nd ventilation path.

  As described above, according to the reciprocating saw 1 of the above embodiment, the insulating cover 23 extends to the rear of the main body housing 5 so as to cover all the exhaust ports 16, 16. A concave portion continuous from the opening 16 to the front end of the main body housing 5 is provided, and cooling air discharged from the exhaust port 16 is guided to the front end side of the main body housing 5 between the concave portion and the inner surface of the insulating cover 23, and the blade 15 By forming the first and second air passages 28, 29, and 31 that are discharged forward along the line, all of the cooling air discharged from the exhaust port 16 can be blown out forward of the main body housing 5. Therefore, in addition to the cooling of the main body housing 5, the dust of the material to be cut can be effectively removed with a sufficient blowing strength, and the cut portion is not easily seen by the dust during the operation, and it is easy to use. . In particular, since the ventilation path is formed by the concave portion provided on the main body housing 5 side, the shape of the insulating cover 23 is simplified and easy to hold, and good operability can be obtained.

In addition, since a plurality of recesses are provided and a plurality of air passages are formed so as to open independently at the front end of the main body housing 5, turbulence of cooling air is less likely to occur due to the independence of the air passages. Smooth blowing out to the front of the housing 5 is possible.
Further, a third air passage 33 is formed between the main body housing 5 and the insulating cover 23 so that the cooling air passes through the LED circuit 21 to the front end side of the main body housing 5 and is discharged forward. It is possible to effectively prevent dust from adhering to the LED circuit 21, and work in a dark place can be performed without any trouble, and the cooling effect of the LED circuit 21 can be obtained.
In addition, since a plurality of protrusions 26 are erected in the front-rear direction on the inner surface of the portion of the insulating cover 23 where the exhaust port 16 is attached, the insulating cover at the exhaust port 16 portion without closing the exhaust port 16 The shape of 23 is maintained, and the cooling air from the exhaust port 16 can be reliably guided forward.

In the above embodiment, the structure is described in which the housing is composed of the motor housing and the main body housing. However, the present invention is naturally applicable even if the housing is an integral housing. Further, the position and shape of the recess that forms the air passage is not limited to the groove or the outer space of the rib provided in the corner of the main body housing as in the above embodiment, but may be provided in the center or the side surface of the upper surface of the main body housing. However, the number may be increased or decreased as appropriate.
Furthermore, the protrusion on the inner surface of the insulating cover is not limited to the exhaust port portion, but can be formed long in the front-rear direction like the lower protrusion 36 in the above-described form.
On the other hand, the ventilation passage for the illuminating body is not limited to the one formed between the protrusion of the insulating cover and the lower surface of the light unit as in the above-mentioned form, It may be formed between the inner surface of the insulating cover.

It is side surface explanatory drawing of a reciprocating saw. It is a plane explanatory view of a reciprocating saw. It is bottom face explanatory drawing of a reciprocating saw. (A) is an AA line sectional view, (b) is a BB line sectional view, and (c) is a CC line sectional view. It is a side view of an insulating cover. It is front explanatory drawing of a reciprocating saw. It is a cross-sectional view of the insulating cover of the exhaust port portion.

Explanation of symbols

1. Reciprocating saw, 2 Motor housing, 3 Motor, 4 Output shaft, 5 Body housing, 6 Slider, 8 Lower housing, 10 Upper housing, 15 Blade, 16 Exhaust port, 17 Fan, DESCRIPTION OF SYMBOLS 20 ... Light unit, 21 ... LED circuit, 23 ... Insulation cover, 25 ... Cylindrical part, 26, 36 ... Projection, 27 ... Groove part, 28, 29 ... 1st ventilation path, 31 ... 2nd ventilation path, 33 ... Third air passage.

Claims (4)

A metal housing with an insulating cover is provided with a slider that reciprocates as the motor rotates, and a blade connected to the tip of the slider projects forward from the housing, while the rear of the housing, A cutting tool provided with an exhaust port for cooling air of the motor,
The insulating cover extends to the rear of the housing so as to cover all the exhaust ports, and a concave portion continuous from the exhaust port to the front end of the housing is provided on the outer surface of the housing. A cutting tool characterized in that an air passage that guides cooling air discharged from the exhaust port to the front end side of the housing and discharges it forward along the blade is formed between the inner surface and the inner surface.   The cutting tool according to claim 1, wherein a plurality of recesses are provided, and a plurality of air passages are formed so as to open independently at the front end of the housing.   If the housing is provided with an illuminating body capable of illuminating the front of the blade, cooling air is guided between the housing and the insulating cover through the illuminating body to the front end side of the housing, The cutting tool according to claim 1 or 2, wherein a ventilation passage for an illuminating body to be discharged forward is formed. The cutting tool according to any one of claims 1 to 3, wherein a plurality of protrusions are erected in the front-rear direction on at least an inner surface of a portion of the insulating cover where the exhaust port is attached.

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