JP2007130771A - Electromotive cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromotive cutting tool capable of stably blowing off the chips accumulated on a marking line by cutting even if cutting depth or the angle of inclination to the surface plate of a main body part is adjusted. <P>SOLUTION: An air flow channel 26 for discharging the air used for cooling a motor is formed to casing 13 and 14, the nozzle 27 communicating with the air flow channel 26 is fixedly provided to the supporter 8 of the surface plate 5, the tip of the nozzle 27 is arranged in the vicinity of the leading end of the surface plate 5, and the nozzle 27 and the air flow channel 26 are connected to each other so as to be always kept in the mutual communication of them corresponding to the air flow channel 26 moved by adjusting cutting depth. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hand-held electric cutting tool that performs a cutting operation, and particularly to a chip processing mechanism that eliminates chips generated by cutting in a circular saw.

  Conventionally, for example, a hand-held circular saw is used as a cutting tool. The circular saw includes a flat platen that can slide on the upper surface of the workpiece, and a main body attached to the platen.

  The operator holds the main part of the circular saw with his / her hand and slides the surface plate on the work material while visually checking the mark on the work material such as wood, for example, along the black line. Cutting work is performed by guiding the cutting edge of the blade. However, in such a cutting operation, the chips generated by the cutting remain on the black line, and the black line that is the mark in the direction to cut from now on can not be seen, and the cutting edge is separated from the black line, and the cutting operation is accurate and accurate. There is a problem that can not be.

  In order to solve such a problem, a technique has been proposed in which cooling air used for cooling a motor is used for blowing off chips (see Patent Documents 1 to 3).

  For example, the portable cutting tool disclosed in Patent Document 1 blows the wind pressure generated by the cooling fan of the electric power tool to the tip of the base through the guide pipe provided in the gear case, and blows off the chips generated by cutting, This prevents the chips from accumulating on the black line.

  The electric cutting tool disclosed in Patent Document 2 cuts from a through hole provided in a connecting member that releases air used for cooling a motor and engages a surface plate or a through hole provided in a front edge portion of a surface plate. In particular, the air discharged from the through hole provided in the front edge blows away the chips generated by cutting, and the chips are accumulated on the black line. Is preventing.

  The electric saw disclosed in Patent Document 3 guides the air of the motor cooling fan to the front part of the outer periphery of the casing that covers the upper part of the blade, and is arranged so that the air is directed to the index attached to the front of the base. It guides to the nozzle which is blown, and blows away the chips generated by the cutting by the air, thereby preventing the chips from accumulating on the black line.

Japanese Utility Model Publication No. 55-154101 Japanese Utility Model Publication No.59-99702 Utility Model Registration No. 3072537

  However, in the cutting tools disclosed in Patent Documents 1 to 3, the casing is rotated up and down in order to change the cutting depth of the cutting blade, thereby releasing air for blowing off chips generated by the cutting. Since the direction and the amount of blowing are changed, in some cases, inconveniences such as inability to blow off the chips on the ink line have occurred.

  Further, as disclosed in Patent Document 2, when a through hole is provided in the surface plate, there is a problem that the direction of the air blown into the through hole is changed by the rotation of the casing, and the blowing amount is changed. There is a problem that the strength of the board becomes weak and it is easily deformed.

  In addition, when the inclination angle of the main body with respect to the surface plate is adjusted for inclined cutting, the direction and amount of air blown to blow off the chips generated by the cutting change. Inconveniences such as not being able to blow off the chips.

  Accordingly, an object of the present invention is to provide an electric cutting tool that can stably blow off chips accumulated on the black line by cutting even if the cutting depth and the inclination angle of the main body with respect to the surface plate are adjusted. And

  In order to solve the above-mentioned problem, an electric cutting tool (1A, 1B) according to claim 1 includes a flat platen (5), a cutting blade (11), a drive unit that rotationally drives the cutting blade, A main body (10) including a casing (13, 14) for accommodating a fan for cooling the drive unit is attached via a supporter (8) erected on the surface plate, and moves the casing up and down. Thus, in the electric cutting tool capable of adjusting the cutting depth of the cutting blade, the casing is formed with an air flow path (26) for introducing air after cooling of the drive unit by the fan, and the supporter The nozzle (27) whose front end is disposed in the vicinity of the front end of the surface plate and whose rear end communicates with the air flow path is fixedly attached, and the nozzle and the air flow path have the depth of cut. Move by adjusting That wherein the contact corresponding to the air flow passage the nozzle and the air flow path is always connected so as to maintain.

  The electric cutting tool according to claim 2 is the electric cutting tool according to claim 1, wherein the rear end portion of the nozzle and the front end portion of the air flow path have the same axis as the center. It is formed in an arc shape.

  Moreover, the electric cutting tool according to claim 3 is the electric cutting tool according to claim 1, wherein the rear end of the nozzle and the front end of the air flow path are disposed in contact with each other on the axis of the shaft. Features.

  Moreover, the electric cutting tool (1C) according to claim 4 includes a cutting blade on a flat plate and a casing that houses a driving unit that rotationally drives the cutting blade and a fan that cools the driving unit. The main body provided is attached via a supporter standing on the surface plate, and the cutting depth of the cutting blade can be adjusted by rotating the casing up and down around an axis provided on the supporter. In the electric cutting tool capable of inclining the cutting blade by inclining the casing with respect to the surface plate, an air flow path (37) for introducing air after cooling the drive unit by the fan into the casing And a nozzle (39) having an opening (39a, 39b) for blowing off chips generated by cutting and a communication port (39c) communicating with the air flow path. The air channel and the nozzle communication port are always connected to the nozzle and the air channel corresponding to the air channel that moves by adjusting the depth of cut or tilting the casing. It is connected via a communication member (38) to be maintained.

  According to the first to fourth aspects of the present invention, the air flow path and the nozzle are connected so as to maintain communication corresponding to the air flow path that moves by adjusting the cut depth. The adjustment can maintain the communication between the air flow path and the nozzle without changing the position of the air discharged from the nozzle and the blowing amount even if the main body moves. Therefore, even if the main body moves by adjusting the cutting depth, it is possible to stably blow air for blowing off the chips onto the black line. Moreover, since the opening for blowing off chips is not formed in the surface plate, the strength of the surface plate does not decrease.

  According to the invention of claim 4, the air flow path and the nozzle are connected via the communication member that always maintains communication between the air flow path and the nozzle in response to the movement of the air flow path. Therefore, not only adjustment of the cutting depth but also communication of the air flow path and the nozzle can be maintained even when the casing is inclined, and air for blowing off the chips can be stably blown onto the black line.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  First, the structure of a hand-held electric circular saw (hereinafter referred to as “circular saw 1A”) in this embodiment will be described with reference to FIGS. For easy understanding, the circular saw 1A of the present embodiment will be described with the left-right direction in FIG. 1 as the front-rear direction of the circular saw and the left-right direction in FIG. 2 as the left-right direction of the circular saw. Further, the circular saw 1A of the present embodiment functions as the electric cutting tool of the present application.

  As shown in FIGS. 1 and 2, the circular saw 1 </ b> A of the present embodiment includes a flat platen 5 that can slide on the upper surface of a workpiece (not shown), and a main body 10 that is attached to the platen 5. And is configured.

  The main body 10 has a disc-shaped circular saw blade 11, a safety cover 12 that covers substantially the upper half of the circular saw blade 11, a driving unit such as a motor (not shown), and a cylinder that houses a fan for cooling the driving unit. Motor case 13 and a cylindrical gear case 14 that accommodates a power transmission unit composed of gears (not shown) that transmits the power of the drive unit to the circular saw blade 11. The driving unit and the circular saw blade 11 are connected to a power transmission unit by a connecting member such as a shaft (not shown), and by driving the driving unit, the power is transmitted to the circular saw blade 11 through the power transmission unit, The circular saw blade 11 rotates.

  As shown in FIG. 2, the safety cover 12 is integrally formed on the upper peripheral surface at the left end of the gear case 14 in the figure, and the gear case 14 is detachably attached to the motor case 13 at the peripheral edge at the right end in the figure. It has been. Further, a handle 15 is attached to the left end of the motor case 13 so that a user who uses the circular saw 1A can hold and move the circular saw 1A in a predetermined direction. In addition, the gear case 14 and the motor case 15 of this embodiment function as a casing of this application.

  As shown in FIG. 1, an arc-shaped slide cover 16 that covers a part of the periphery of the circular saw blade 11 is provided inside the safety cover 12. The slide cover 16 has a substantially U-shaped cross section in a direction orthogonal to the circumferential direction. The slide cover 16 has the same rotation center as the circular saw blade 11 and is disposed so as to be rotatable along the periphery of the circular saw blade 11. When the work is not performed, as shown in FIG. The lower part of the saw blade 11 is covered.

  In addition, although not shown, the surface plate 5 is formed with an opening for projecting the cutting edge of the circular saw blade 11 downward. Further, as shown in FIGS. 2 and 3, the first aim 5 a and the second sight composed of a “U” -shaped notch are formed at the front left end of the surface plate 5 in front of the circular saw blade 11. An aim 5b is formed. The sights 5a and 5b are for cutting along the black lines marked on the material to be cut along the sights 5a and 5b during the work.

  As shown in FIGS. 1 and 4, the main body 10 and the surface plate 5 are arranged so that the front portions of the safety cover 12 and the gear case 14 are located on the rear side of the bracket 6 erected at the front end portion of the surface plate 5. It is pivotally supported by a pair of projecting portions 8a and pins 9 which are formed so as to project rearward from a supporter 8 which is pivotably attached to the bracket 6 via a fulcrum pin 7. Further, as shown in FIG. 1, the rear portion of the safety cover 12 is erected on the rear portion of the surface plate 5 via a strip-like cut depth adjusting plate 21 that slides along the inner peripheral surface of the safety cover 12. A pair of projecting portions 24 a that are formed to project forward from a supporter 24 that is rotatably attached to the bracket 22 via a fulcrum pin 23 on the front side of the bracket 22 that is formed, and are connected by pins 25. Yes. The safety cover 12 (main body portion 10) rotates about the stroke of the cutting depth adjusting plate 21 around the front pin 9 as an axis, and adjusts the protruding amount of the circular saw blade 11 protruding from the lower surface of the surface plate 5. Can be done.

  The main body 10 is fixed to the surface plate 5 so as to be swingable. As shown in FIG. 2, the brackets 6 and 22 erected on the front and rear sides of the surface plate 5 are formed with a plate 6b having an opening 6a in an arc shape, and the supporter 8 is connected to the support 6 through the opening 6a. The main body 10 can be tilted at a predetermined angle by a tilt angle adjusting screw 6c to be screwed and fixed in the front-rear direction (for the rear plate or the like, the structure is the front plate 6b). The illustration and description are omitted because they are the same as the above. Thus, the circular saw 1A can cope with a cutting operation in a state inclined to the left and right with respect to the front-rear direction, so-called inclined cutting.

  As shown in FIGS. 1 and 3, the gear case 14 is formed with an outlet 14 b that blows air after cooling of the drive unit by the fan toward the circular saw blade 11 by a partition wall (not shown). A partition wall 25 that faces a part of the front opening of the outlet 14b has a predetermined interval with respect to each of the substantially intermediate positions of the outer wall 14a of the gear case 14 and the circular saw blade 11, and the circular saw blade 11 side by a set screw 29 on the outer wall 14a. Is attached. Moreover, as shown in FIG.1 and FIG.4, the up-and-down two standing wall 14c in the figure is integrally formed in the front circular saw blade 11 side of the outer wall 14a. An air flow path 26 is formed at the front end portion of the standing wall 14 c and the partition wall 25. Thus, the air flow path 26 into which the air flowing out from the ejection port 14 b is introduced is formed to extend forward using the partition wall 25 and the outer wall 14 a of the gear case 14.

  In addition, the supporter 8 is provided with a cylindrical nozzle 27 having a distal end extending in the vicinity of the first and second sights 5 a and 5 b and a rear end extending rearward of the supporter 8. Between the pin 9 that attaches the supporter 8 to the supporter 8 and the fulcrum pin 7 that attaches the supporter 8 to the bracket 6.

  An engagement portion 28 that engages with the nozzle 27 is formed on the inner end of the air flow path 26, and a rear end portion of the tubular nozzle 27 is inserted into the engagement portion 28. The rear end peripheral surface of the nozzle 27 can slide on the inner peripheral surface of the air flow path 26. More specifically, as shown in FIG. 1, the outer periphery of the rear end portion of the nozzle 27 and the engaging portion 28 of the air flow path 26 are formed in an arc shape having the same center as the axis of the pin 9. Along with the vertical rotation of the main body 10 around the pin 9, the rear end of the nozzle 27 and the engagement portion 28, which is the inner peripheral surface of the air flow path 26, are freely slidable.

  Here, a mechanism for blowing off chips generated by cutting will be described.

  In the circular saw 1A of the present embodiment, for example, a fan (not shown) is integrally attached to a peripheral surface of a motor shaft (not shown) that connects a motor that is a drive unit and a power transmission drive unit that is a combination of gears. The fan rotates integrally with the motor shaft. The rotation of the fan 5 sucks air from an opening (not shown) formed on the right side of the motor case 13 in FIG. 2 to cool the heat generated by the motor and the sliding portions. The air that has cooled the motor is sent out to the air outlet 14b after the motor is cooled, as indicated by the arrows in FIG. A part of the air is guided to the partition wall 25 facing a part of the air outlet 14b, and further flows into the air flow path 26 formed by the partition wall 25 and the standing wall 14c provided on the outer wall 14a of the casing 14. , And is discharged to the outside through the nozzle 27.

  In addition, since the tip of the nozzle 27 extends near the first and second sights 5a and 5b, the air is discharged near the sights 5a and 5b. As a result, the chips accumulated on the black line are blown off, and the visibility can be kept good.

  In the circular saw 1A configured as described above, when adjusting the protruding amount of the circular saw blade 11 from the surface plate 5, particularly when the protruding amount of the circular saw blade 11 is adjusted to be shallow, as shown in FIG. In addition, the air flow path 26 also moves in the upward direction as the main body part 10 rotates about the pin 9 as a rotation center, and the inner peripheral surface of the engaging part 28 of the air flow path 26, Since the rear end portion of the nozzle 27 that engages with the inner peripheral surface is formed in an arc shape with the axis of the pin 9 as the same center, the rear end peripheral surface of the nozzle 27 is used to move the air flow path 26. Correspondingly, the inner circumferential surface of the engaging portion 28 of the air flow path 26 is freely slid in the vertical direction, and the communication between the nozzle 27 and the air flow path 26 is maintained. As shown by the arrows, the position of the nozzle 27 does not change even if the air flow path 26 moves, and the fan releases air. Earlier also it does not change. Therefore, even when cutting with the cutting depth of the circular saw blade 11 adjusted, air is always released to a fixed position, so that the chips accumulated on the black line generated by the cutting can be stabilized. It can be blown away.

  Further, even when the circular saw 1 </ b> A is used with the main body 10 tilted with respect to the surface plate 5, the nozzle 27 attaches the pin 9 that attaches the main body 10 to the supporter 8 to the bracket 6. Since it is provided near the fulcrum pin 7 and in the vicinity of the fulcrum pin 7, the position of the nozzle 27 with respect to the surface plate 5 does not change greatly even if the air flow path 26 moves, and air is released by the fan. The destination will not change greatly. Therefore, even when cutting with the main body 10 tilted, it is possible to stably blow away the chips accumulated on the black line generated by the cutting.

  If the nozzle 27 is further divided into two parts, one is attached to the bracket 6 and connected to each other by a flexible joint, the position of the nozzle 27 does not change, and the air discharge destination by the fan can be kept unchanged.

  Next, another embodiment of the air channel and nozzle mounting structure will be described with reference to FIGS. 6 and 7, the same reference numerals are given to portions common to FIGS. 1 to 3, and description thereof is omitted.

  In the present embodiment, an air flow path 32 is formed using the partition wall 31 and the outer wall 14 a of the gear case 14, and a cylindrical nozzle 33 communicating with the air flow path 32 is provided on the bracket 6 erected on the surface plate 5. The supporter 8 is rotatably attached to the rear side via a fulcrum pin 7 so as to be fixed by screws 34 or the like.

  The tip of the nozzle 33 is disposed so as to extend in the vicinity of the first and second sights 5 a and 5 b, and the rear end is attached in contact with the tip of the air flow path 32. The tip of the air flow path 32 that communicates with the nozzle 33 is provided with an opening 35 on the same line as the axis of the pin 9. The opening of the nozzle 33 communicating with the opening 35 of the air flow path 32 is formed in the same shape.

  The circular saw 1B configured in this manner is used to adjust the amount of protrusion of the circular saw blade 11, particularly when the amount of protrusion is adjusted to be shallow. The front end of the path 32 rotates relative to the supporter 8, but the rear end of the nozzle 33 and the front end of the air flow path 32 are disposed in contact with the axis of the pin 9. With this rotation, the end surface of the air flow path 32 slides with the end surface of the air flow path 32, and the communication between the nozzle 33 and the air flow path 32 is maintained, so that the front end of the air flow path 32 rotates. Even so, the position of the nozzle 33 does not change, and the air discharge destination by the fan does not change. Therefore, even when cutting with the cutting depth of the circular saw blade 11 adjusted, it is possible to stably blow away the chips accumulated on the black line generated by the cutting.

  Next, another embodiment of the air channel and nozzle mounting structure will be described with reference to FIGS. 8 and 9, the same reference numerals are given to portions common to FIGS. 1 to 3, and description thereof is omitted.

  In the present embodiment, an air flow path 37 is formed using the partition wall 36 and the outer wall 14a of the gear case 14, and the air flow path 37 is connected to a cylindrical nozzle 39 via a hose 38 made of an elastic rubber material or the like. Has been.

  The hose 38 may be a metal bellows pipe that can be bent freely. In addition, the hose 38 of this embodiment functions as a connection member of this application.

  The nozzle 39 has openings 39a and 39b at both ends. One of the openings 39a extends near the first and second sights 5a and 5b, and the other opening 39b has a circular saw blade. 11 extends in the vicinity of the front. The nozzle 39 is fixedly attached to the surface plate 5 with screws 40 or the like. Further, a communication port 39c for communicating with the hose 38 is formed in the vicinity of the center of the nozzle 39. The nozzle 39 is connected to the hose 38 through the communication port 39c, and the other end of the hose 38 is connected. Is connected to the air flow path 37.

  The circular saw 1 </ b> C configured in this way is not shown in the drawing when adjusting the protrusion amount of the circular saw blade 11, particularly when the protrusion amount is shallowly adjusted, but with the upward movement of the main body. Although the air flow path 37 also moves, since the air flow path 37 is connected to the nozzle 39 by the elastic hose 38, the communication between the nozzle 39 and the air flow path 37 is always maintained, and the air flow path 37 moves. However, the position of the nozzle 39 does not change, and the air discharge destination by the fan does not change. Therefore, even when the cutting is performed with the cutting depth of the circular saw blade 11 adjusted, it is possible to blow away the chips accumulated on the black line generated by the cutting.

  Further, in this embodiment, even when the circular saw 1C is used with the main body portion 10 inclined with respect to the surface plate 5, the air flow path 37 is fixed to the surface plate 5 by the elastic hose 38. Since the nozzle 39 is connected, the communication between the nozzle 39 and the air flow path 37 is maintained, and even if the air flow path 37 moves, the position of the nozzle 39 does not change. Will not change. Therefore, even when cutting with the main body 10 tilted, it is possible to stably blow away the chips accumulated on the black line generated by the cutting.

  In addition, about the attachment structure of the nozzle and air flow path in a present Example, it can comprise by combining the said embodiment suitably. In addition, if the tip portions of the nozzles 27, 33, and 39 are configured to freely change their directions, it becomes easier to use.

  Further, although the electric circular saw has been described as an embodiment of the present invention, the present invention can be applied to other hand-held electric cutting tools such as jigsaws, routers, and trimmers.

It is a partial cross section front view of the electric circular saw of this invention. It is a right view of the electric circular saw of this invention. It is a partial cross section top view of the electric circular saw of this invention which shows the structure inside a casing. It is AA sectional drawing of FIG. It is B enlarged view of FIG. It is a partial cross section top view which shows the structure inside the casing in the electric circular saw of other embodiment. It is a right view of the electric circular saw shown in FIG. It is a partial cross section top view which shows the structure inside the casing in the electric circular saw of other embodiment. It is a right view of the electric circular saw shown in FIG.

Explanation of symbols

1A, 1B, 1C Circular saw 5 Surface plate 6 Bracket 8 Supporter 9 Pin 11 Circular saw blade 10 Main body 13 Motor case 14 Gear case 25, 31, 36 Bulkhead 26, 32, 37 Air flow path 27, 33, 39 Nozzle

Claims (4)

A platen surface plate is provided with a cutting blade, a drive unit that rotationally drives the cutting blade, and a casing that houses a fan that cools the drive unit. In the electric cutting tool capable of adjusting the cutting depth of the cutting blade by rotating the casing up and down around an axis provided on the supporter,
In the casing,
An air flow path for introducing air after cooling of the drive unit by the fan is formed,
The supporter includes
The tip is arranged near the tip of the surface plate, and the nozzle whose rear end is in communication with the air flow path is fixedly attached,
The nozzle and air flow path are
An electric cutting tool characterized by being connected so as to always maintain communication between the nozzle and the air flow path corresponding to the air flow path that moves by adjusting the depth of cut.   2. The electric cutting tool according to claim 1, wherein the rear end portion of the nozzle and the front end portion of the air flow path are formed in an arc shape having the same center as the axis of the shaft.   The electric cutting tool according to claim 1, wherein the rear end of the nozzle and the front end of the air flow path are disposed in contact with each other on the axis of the shaft. A platen surface plate is provided with a cutting blade, a drive unit that rotationally drives the cutting blade, and a casing that houses a fan that cools the drive unit. The cutting depth of the cutting blade can be adjusted by rotating the casing up and down around an axis provided on the supporter, and by tilting the casing with respect to the surface plate In the electric cutting tool capable of tilting the cutting blade,
In the casing,
An air flow path for introducing air after cooling of the drive unit by the fan is formed,
On the surface plate,
A nozzle having an opening that blows away chips generated by cutting and a communication port that communicates with the air flow path is fixedly attached,
The communication port of the air flow path and the nozzle is connected via a communication member that always maintains communication between the nozzle and the air flow path corresponding to the air flow path that moves by adjusting the depth of cut or tilting the casing. An electric cutting tool characterized by being connected.

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