JP2013049114A - Electric tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a wind volume as a motor cooling wind for a long period of time by avoiding the adhesion of dust and the accumulation of the dust at an air intake portion while dust-removing outside air which is sucked into an electric tool as the motor cooling wind for cooling a drive motor.SOLUTION: A separator 40 is arranged at the outside-air suction side of a motor housing incorporated with the electric motor. The separator 40 centrifugally separates the sucked outside air as the motor cooling wind for cooling the drive motor so that the outside air sucked into a disk grinder may be utilized as a clean motor cooling wind. Furthermore, since the dust or the like mixed in the outside air is only centrifugally separated by the separator 40, the dust or the like is not adhered to or accumulated on an air intake part 45. Furthermore, the air intake part 45 functions as a discharge part for discharging separated matters separated in a centrifugal separation chamber 55 to the outside.

Description

  The present invention relates to an electric tool incorporating a drive motor as a power source.

  For example, a power tool such as a disk glider incorporates a drive motor as a power source. This drive motor is an electric motor that rotates the spindle by supplying electric power. The drive motor uses a rotational driving force of the spindle to rotate a member such as a grindstone to function as an electric tool. At this time, the built-in drive motor generally generates heat due to the generation of the rotational driving force. For this reason, in such an electric tool, a cooling fan for cooling the drive motor is provided to remove heat from the drive motor. This cooling fan is attached to the spindle of the drive motor described above so as to be integrally rotatable. The cooling fan mounted in this manner rotates with the rotation of the spindle, sucks air outside the power tool (outside air) into the power tool, and blows it toward the drive motor as motor cooling air. Yes.

By the way, an electric component such as a drive motor is built in the electric tool described above. For this reason, if dust is mixed with the motor cooling air described above, these electric components are defective. Therefore, in the outside air sucked as the motor cooling air as described above, it is necessary to filter it so as to remove dust mixed in the outside air.
Therefore, various structures are provided in the intake portion of such a power tool in order to remove dust mixed in the sucked outside air. For example, a complicated air passage (labyrinth structure) is provided in an intake portion sucked into the electric tool from the outside of the electric tool (see Patent Document 1), or a dust filter is provided in the intake portion sucked into the electric tool. A technique of arranging (see Patent Document 2 and Patent Document 3) is known. According to such a technique, when the outside air used as the motor cooling air flowing toward the drive motor is sucked into the electric tool, dust mixed with the outside air can be removed, and the clean air can be used as the motor cooling air. It can be sprayed toward the drive motor.

JP 2008-302467 A Japanese Utility Model Publication 2-85555 Japanese Patent Application Laid-Open No. 2002-283255

  However, it has been pointed out that the technique for disposing the labyrinth structure described above is insufficient in removing dust from the outside air sucked into the power tool. Further, in the technique of disposing the dust removal filter described above, when an electric tool is used for a long time, dust adheres to the dust removal filter and accumulates. If it does so, the air permeability of a dust removal filter will be inhibited, the pressure loss at the time of external air suction will become large, and the air volume as motor cooling air will be reduced. As a result, the drive motor cannot be sufficiently cooled.

  The present invention has been made in view of such circumstances, and the problem to be solved by the present invention is an electric tool incorporating a drive motor as a power source, and an electric tool as motor cooling air for cooling the drive motor. It is intended to maintain the air volume as the motor cooling air over a long period of time while avoiding dust adhesion and dust accumulation in the intake portion while being able to remove the outside air sucked into the air.

In solving the above-described problems, the power tool according to the present invention takes the following means.
That is, the electric tool according to the first aspect of the present invention includes a drive motor that is a power source, and a motor cooling fan that is attached to a shaft that is rotated by the drive motor so as to be integrally rotatable and sucks outside air. A hand-held power tool, provided on the outside air suction side of the main housing housing the drive motor, is provided with a separating device for separating the sucked outside air into a motor cooling air for cooling the motor by a centrifugal separation function. It is characterized by being.
According to the electric tool of the first aspect of the present invention, since the separation device is provided on the outside air suction side of the main body housing that houses the drive motor, the sucked outside air is used as motor cooling air for cooling the drive motor. Separation is possible with a centrifuge function. As a result, dust and the like mixed in the outside air (hereinafter referred to as “dust etc.” including dust and water droplets) can be separated, exhibiting dust removal effect, and sucked into the power tool The outside air can be used as clean motor cooling air. Further, since dust and the like mixed in the outside air are only separated by the centrifugal separation function of the separation device, the dust and the like do not adhere to or accumulate on the intake portion. Thereby, the pressure loss at the time of sucking outside air can be eliminated, and the air volume as the motor cooling air can be maintained. Therefore, according to the electric tool according to the first aspect of the present invention, it is possible to remove the outside air sucked into the electric tool as the motor cooling air for cooling the drive motor, while adhering dust and the like in the intake portion and the dust. Thus, it is possible to maintain the air volume as the motor cooling air over a long period of time while avoiding such accumulation.

The power tool according to a second aspect of the present invention is the power tool according to the first aspect of the present invention, wherein the separation device includes a device housing in which a centrifuge chamber is formed that exhibits a centrifuge function while forming an exterior. An air intake section provided on a peripheral surface of the apparatus housing and sucking outside air toward the centrifuge chamber, wherein the air intake section discharges the separated material separated in the centrifuge chamber to the outside It functions as a discharge part.
In the electric power tool according to the second aspect of the invention, the air intake portion functions as a discharge portion for discharging the separated material separated in the centrifugal separation chamber to the outside. A separated matter of outside air separated from the wind (corresponding to the “dust etc.” described above) can be discharged outside without accumulating in the centrifuge chamber. This eliminates the need for a storage box for storing the separated air. Therefore, the separation device can be reduced in size, and the power tool can be reduced in size.

The electric power tool according to a third aspect of the invention is the electric power tool according to the second aspect of the invention, in which when the suction of outside air from the air intake section is stopped on the partition wall that defines the centrifugal separation chamber, the centrifugal separation is performed. A discharge guide shape is provided that acts to discharge the separated product in the chamber out of the intake portion by its own weight.
According to the electric tool of the third aspect of the invention, since the discharge guide shape is provided on the partition wall that divides the centrifugal separation chamber, when the suction of outside air from the intake portion stops, the centrifugal separation chamber is Thus, the separated product can be easily discharged out of the intake portion by the weight of the separated product. This eliminates the need for discharge maintenance for discharging the separated product. As a result, the power tool is easy to use.

A power tool according to a fourth invention is characterized in that, in the power tool according to any one of the first to third inventions, an outer portion of the separating device functions as a grip of the power tool.
According to the power tool of the fourth aspect of the invention, since the outer portion of the separating device functions as the grip of the power tool, the power tool can maintain the air volume while removing the outside air as the motor cooling air described above. A function as a grip is also added. That is, the function of the grip of the electric tool can also be used as the separation device, and the electric tool can be made compact.

The power tool according to a fifth aspect of the present invention is the power tool according to the fourth aspect of the present invention, wherein the airflow guide portion that guides the outside air sucked from the suction portion so as to generate an airflow in the centrifugal separation chamber, It is provided inside the device housing.
According to the electric tool according to the fifth aspect of the invention, the airflow guide portion that guides the outside air sucked from the intake portion so as to generate an airflow in the centrifugal separation chamber is provided inside the apparatus housing. The degree of freedom in selecting the shape of the outer portion of the device housing can be increased. Thereby, the shape selection range in forming the grip shape on the outer portion of the separation device can be expanded.

A power tool according to a sixth aspect of the present invention is the power tool according to any one of the second to fifth aspects, wherein a plurality of the intake portions are disposed with a space from the peripheral surface of the device housing. It is characterized by.
According to the electric tool of the sixth aspect of the present invention, since a plurality of the intake portions are disposed with a distance from the peripheral surface of the device housing, an intake region for sucking outside air can be secured. The air volume can be secured. Furthermore, in the case where the intake portion functions as a discharge portion that discharges the separated matter, a discharge region for discharging the separated matter can be secured in a plurality of directions. Accordingly, it is possible to ensure the function of discharging the separated matter regardless of the posture of the electric tool while ensuring the air volume for cooling the drive motor.

According to a seventh aspect of the present invention, there is provided the electric power tool according to any one of the second to sixth aspects, wherein the intake portion disposed on the peripheral surface of the device housing is positioned at the electric power tool. It is characterized in that it is set at a position facing in the direction of gravity with respect to the peripheral surface of the device housing in the regular stationary posture of the tool.
According to the electric tool of the seventh aspect of the invention, since the position of the intake portion is set to a position facing the circumferential direction of the device housing in the regular stationary posture of the electric tool, the electric tool When the intake portion functions as the discharge portion in the regular stationary posture, it is possible to easily discharge the intake portion to the outside by the weight of the separated matter. Thereby, the function for discharging the separated material of the electric tool in the regular stationary posture can be further enhanced.

An electric power tool according to an eighth invention is characterized in that, in the electric power tool according to any one of the first to seventh inventions, the separating device is configured to be removable from the main body housing.
According to the power tool according to the eighth aspect of the present invention, since the separation device is configured to be removable from the main body housing, the conventional configuration can be used up to the main body housing. As a result, the configuration other than the separation device can be configured as before.

According to the electric tool of the first aspect of the invention, it is possible to remove the outside air sucked into the electric tool as the motor cooling air for cooling the drive motor, while adhering dust or the like and depositing dust or the like in the intake portion. Thus, the air volume as the motor cooling air can be maintained over a long period of time.
According to the electric tool according to the second aspect of the invention, the separation device can be reduced in size, and consequently the electric tool can be reduced in size.
According to the power tool of the third invention, it is not necessary to perform discharge maintenance for discharging the separated material, and the power tool is easy to use.
According to the electric tool of the fourth invention, the function of the grip of the electric tool can also be used as the separating device, and the electric tool can be made compact.
With the electric tool according to the fifth aspect of the present invention, the shape selection range for forming the grip shape on the outer portion of the separation device can be expanded.
According to the electric tool of the sixth aspect of the invention, it is possible to ensure the function of discharging the separated matter regardless of the posture of the electric tool while ensuring the air volume for cooling the drive motor.
According to the power tool of the seventh invention, it is possible to enhance the function of discharging the separated power tool in the regular stationary posture.
According to the electric tool of the eighth invention, the configuration other than the separation device can be configured as before.

It is an external appearance perspective view which shows the external appearance of the electric tool used as 1st Embodiment by a perspective view. It is an external appearance top view which shows the external appearance of the electric tool of FIG. It is sectional drawing which shows the III-III cross-section arrow in FIG. 1 and FIG. It is an external appearance perspective view which shows the external appearance of the separation apparatus of the electric tool used as 1st Embodiment by a perspective view. It is an external appearance side view which shows the external appearance of the separation apparatus of FIG. 4 by a side view. It is an external appearance rear view which shows the external appearance of the separation apparatus of FIG. It is sectional drawing which shows the VII-VII cross-section arrow of the separation apparatus in FIG. It is sectional drawing which shows the VIII-VIII cross section arrow of the separation apparatus in FIG. It is sectional drawing which shows the IX-IX sectional arrow of the separation apparatus in FIG. It is an effect | action schematic diagram which shows the external air attracted | sucked inside the separation apparatus typically. It is an action schematic diagram which shows typically centrifugal separation inside a separation device. It is an effect | action schematic diagram which shows typically discharge | emission of the separated material inside a separation apparatus. It is an effect | action schematic diagram which shows typically the external air attracted | sucked inside the separation apparatus of the electric tool used as 2nd Embodiment. It is an effect | action schematic diagram which shows typically the centrifugation inside the separation apparatus of FIG. It is an operation | movement schematic diagram which shows typically discharge | emission of the separated material inside the separation apparatus of FIG.

[First Embodiment]
Hereinafter, a first embodiment for carrying out an electric tool according to the present invention will be described with reference to FIGS. In the following description, the disc grinder 10 will be described as an example of a hand-held power tool according to the present invention.
FIG. 1 is an external perspective view showing the external appearance of a disc grinder 10 as a power tool in perspective. FIG. 2 is an external top view showing the external appearance of the disc grinder 10 in top view. FIG. 3 is a cross-sectional view of the disc grinder 10 shown in FIGS. 1 and 2 taken along the line III-III. The disk grinder 10 described below defines the top, bottom, front, back, left and right of the disk grinder 10 as shown in the drawing for easy understanding. The upper and lower regulations of the disc grinder 10 are based on the regular stationary posture of the disc grinder 10. That is, the lower side of the disc grinder 10 is the side facing the direction of gravity.
As shown in FIG. 3, the disk grinder 10 includes an output spindle 37 that is rotationally driven, and is a hand-held electric tool that grinds an object to be ground with a grindstone B attached to the output spindle 37. The disc grinder 10 is configured to include a drive motor 23 serving as a power source. The drive motor 23 is configured by an electric brush motor that is rotationally driven by electric power. The disc grinder 10 is used with power supplied from the outside. That is, the disc grinder 10 is configured to include a power cord for connecting to an external household AC power source, and is driven by the power supplied from the household AC power source. . In the illustrated disc grinder 10, in order to make the configuration of the separation device 40 easy to understand, illustration of such a power cord is omitted.

As shown in FIG. 3, the disc grinder 10 includes a tool body 15 having a built-in drive motor 23, and a separation device that separates sucked outside air into dust and the like (dust and water droplets) and motor cooling air by a centrifugal separation function. 40. The motor cooling air passes through while contacting a heat generating member such as the drive motor 23 as shown by a thick chain line in FIG. At this time, the motor cooling air cools the heat generating members such as the drive motor 23.
As shown in FIG. 3, the tool body 15 includes a power generation unit 20 and a power conversion unit 30.
As shown in FIG. 3, the power generation unit 20 is configured to be housed in a motor housing 22 serving as a main body housing. The power generation unit 20 includes a drive motor 23 for rotating the output spindle 37. This drive motor 23 is comprised by the brush motor which comprises the motor spindle 25 as a rotational drive shaft.
In addition, since the drive motor 23 is comprised by the brush motor used widely, detailed description regarding this drive motor 23 is abbreviate | omitted. That is, the drive motor 23 includes a field as a stator, an armature as a rotor, a commutator as a commutator, and a carbon brush, as in a general brush motor, and a motor together with the rotor (armature, commutator). The spindle 25 is rotated integrally. The motor spindle 25 is rotatably supported by bearings 24 arranged at the front and rear ends. The motor spindle 25 corresponds to a rotating shaft according to the present invention that is rotated by the drive motor 23. The motor spindle 25 functions as an output shaft that outputs a rotational driving force from the power generation unit 20 toward the power conversion unit 30. In other words, the motor spindle 25 functions as an input shaft for inputting the rotational driving force from the power generation unit 20 to the power conversion unit 30.

As shown in FIG. 3, the power conversion unit 30 is configured to be housed in a gear housing 32 serving as a main body housing. The power conversion unit 30 converts the rotation direction and the rotation speed related to the rotational driving force input from the motor spindle 25 in order to rotate the output spindle 37. That is, the power conversion unit 30 is configured by meshing the driving side gear 33 and the driven side gear 35. The driving side gear 33 and the driven side gear 35 are constituted by bevel gears (bevel gears). Further, the number of teeth of the driven gear 35 is larger than the number of teeth of the drive side gear 33. The output spindle 37 is attached so as to be rotatable together with the driven gear 35.
Thus, the rotational drive of the output spindle 37 is rotated so that the rotational direction is converted to a direction relatively orthogonal to the rotational direction and the rotational speed is relatively reduced as compared with the rotational drive of the motor spindle 25. Speed has been converted. The rotational torque of the output spindle 37 is higher than that of the motor spindle 25. The output spindle 37 is supported by bearings 38 disposed at the upper and lower end positions of the output spindle 37. Further, a cover body 18 for preventing scattering of grinding powder by the grindstone B is attached to the rear half circumference range of the grindstone B.
The gear housing 32 that houses the power conversion unit 30 configured as described above is provided with an exhaust port 39. The exhaust port 39 is a vent for exhausting motor cooling air sent by a motor cooling fan 27 described below to the outside. For this reason, the exhaust port 39 is formed to be open so as to communicate with the inside and outside of the tool body 15.

A motor cooling fan 27 is attached to the front end portion of the motor spindle 25 described above. The motor cooling fan 27 is attached so as to rotate integrally with the motor spindle 25. Therefore, the motor cooling fan 27 is a so-called centrifugal blower fan that rotates integrally with the motor spindle 25. The rotated motor cooling fan 27 sucks air from the rear side of the tool body 15 in the direction along the rotation axis direction of the motor cooling fan 27 and exhausts air in the direction along the centrifugal direction of the motor cooling fan 27. Act to send. The wind sent in the direction along the centrifugal direction is exhausted to the outside through the exhaust port 39 provided in the gear housing 32 described above. Moreover, the wind sent from the rear side of the tool main body 15 in the direction along the rotational axis direction is the outside air sucked from the suction portion 45 provided in the separation device 40 described later. That is, outside air sucked from an intake portion 45 provided in the separation device 40 described later is sent from the inner rear side of the tool main body 15 toward the inner front side while contacting each member constituting the drive motor 23. . In this way, the motor cooling fan 27 can send air that becomes motor cooling air that cools each member constituting the drive motor 23 from the rear side to the front side of the tool body 15.
The rear side of the tool body 15 is set as the outside air suction side of the motor housing 22. That is, the rear side of the motor housing 22, which is also the rear side of the tool body 15, is provided with a separation device 40 that includes an intake portion 45 for sucking outside air. Here, a connecting portion 29 for connecting a separation device 40 to be described in detail below is provided at the rear end portion of the power generating portion 20. When the separation device 40 is connected to the connection portion 29, the inside of the power generation unit 20 and the separation device 40 is in a communication state in which an air flow path is secured so that air can flow into each other.

Next, the separation device 40 connected to the rear end portion of the power generation unit 20 will be described. The separation device 40 includes an intake portion 45. The intake portion 45 is a portion that sucks outside air by suction air generated by the rotation of the motor cooling fan 27. FIG. 4 is an external perspective view showing the external appearance of the separation device 40 in perspective. FIG. 5 is an external side view showing the external appearance of the separation device 40 in a side view. FIG. 6 is an external rear view showing the external appearance of the separating apparatus 40 in the rear view. FIG. 7 is a cross-sectional view showing the VII-VII cross-sectional arrow of the separating apparatus 40 in FIG. FIG. 8 is a cross-sectional view showing a VIII-VIII cross-sectional view of the separation device 40 in FIG. FIG. 9 is a cross-sectional view showing the IX-IX cross-sectional arrow of the separation device 40 in FIG.
Similar to the widely used centrifugal cyclone structure, the separation device 40 is configured to include a centrifugal separation chamber 55 that rotates an air flow and exhibits a centrifugal separation function. The centrifuge chamber 55 is formed in a double cylindrical structure including an outer device housing 41 and an airflow guide tube portion 51 disposed inside the device housing 41. The separation device 40 is configured to be detachable from the motor housing 22 serving as a main body housing. The outer portion of the separating device 40 attached to the tool body 15 is formed so as to function as a grip of the disc grinder 10. That is, the separation device 40 is formed to have a size and shape that can be grasped by the user.

The device housing 41 is formed in a substantially bottomed cylindrical shape such as a cup shape in which only the front side is opened. That is, the device housing 41 is formed by dividing the function into a conical bottom portion 42 and a cylindrical intake portion 43 in order from the rear side which is the bottom. The conical bottom portion 42 and the cylindrical intake portion 43 are formed by integral molding continuous with each other.
The conical bottom portion 42 is a portion that forms the last portion of the separation device 40, and is a portion that is formed as the above-described centrifuge chamber 55. As shown in FIG. 5 and the like, the conical bottom 42 is formed in a substantially conical shape with a flat apex. Specifically, the conical bottom portion 42 includes a bottom portion 421 that is located at the rearmost portion and has a flat apex, and a conical portion 422 that increases the inner peripheral diameter from the bottom portion 421 toward the front side. That is, a range defined by the bottom portion, 421, the conical portion 422, and the rear end opening 531 of the airflow guide tube portion 51 described below is formed as the centrifuge chamber 55 according to the present invention. Yes. That is, the centrifuge chamber 55 is provided in the apparatus housing 41 and exhibits a centrifuge function that separates the outside air sucked from the air intake portion 45 into the motor cooling air and dust (such as dust and water droplets) described above. It corresponds to the space. The cylindrical intake portion 43 is formed in a shape that is continuous with the foremost end of the conical bottom portion 42. The cylindrical intake portion 43 has an inner peripheral diameter that is substantially the same as the opening diameter of the foremost end of the conical bottom portion 42 and is formed in a substantially cylindrical shape. Moreover, the bottom part, 421, and conical part 422 which divide this centrifuge chamber 55 are equivalent to the division wall which divides the centrifuge chamber based on this invention. Here, the inner wall surface 425 of the bottom part 421 and the conical part 422 facing the centrifugal separation chamber 55 intersects the horizontal direction (vertical direction, horizontal inclination when the disc grinder 10 is in a regular stationary posture). Direction). Note that the inner wall surface 425 of the conical portion 422 extends in a direction inclined with respect to the horizontal direction when the disc grinder 10 is in a regular stationary posture, and the inner wall surface 425 of the conical portion 422 is the present invention. This corresponds to the shape of the discharge guide. That is, as shown in FIG. 7, the inner wall surface 425 of the conical portion 422 is formed so as to be inclined downward from the rear side toward the front side.

An intake portion 45 is provided on the peripheral surface 431 of the cylindrical intake portion 43. The intake portion 45 is provided on the peripheral surface 431 of the cylindrical intake portion 43 in order to suck outside air toward the inside of the centrifugal separation chamber 55 by suction air generated by the rotation of the motor cooling fan 27 described above. A plurality of the intake portions 45 are arranged at equal intervals with respect to the peripheral surface 431 of the cylindrical intake portion 43. Specifically, the four intake portions 45 are provided at equal intervals with respect to the peripheral surface 431 of the cylindrical intake portion 43 so as to be positioned in the illustrated vertical and horizontal directions of the disc grinder 10. That is, one intake portion 45 of the four intake portions 45 is located at a position facing the lower side of the disc grinder 10 at a position facing the gravitational direction in the regular stationary posture of the disc grinder 10. The surface 431 is disposed.
The intake portion 45 includes a housing opening 46 and an intake guide portion 47. That is, a housing opening 46 that communicates the inside and the outside of the device housing 41 is provided on the peripheral surface 431 of the cylindrical intake portion 43 that forms the device housing 41. The housing opening 46 is formed so as to allow the inside and outside of the peripheral surface 431 of the cylindrical intake portion 43 to communicate with each other in order to suck outside air into the centrifuge chamber 55 described above. The opening shape of the housing opening 46 is formed in a substantially rectangular shape extending in a direction along the rotation axis direction of the motor cooling fan 27.

  The intake guide 47 is provided outside the housing opening 46. The intake guide part 47 guides the outside air sucked into the centrifugal separation chamber 55 through the intake part 45. That is, the intake guide unit 47 guides the sucked outside air so that the outside air sucked into the centrifugal separation chamber 55 through the intake portion 45 becomes a rotating air flow that exhibits a centrifugal separation function in the centrifugal separation chamber 55. To do. The intake guide portion 47 is provided outside the peripheral surface 431 of the cylindrical intake portion 43 described above. Specifically, the intake guide portion 47 enters the inside of the device housing 41 where the outside air sucked by the rotation of the motor cooling fan 27 enters from the tangential direction of the peripheral surface 431 of the cylindrical intake portion 43. Designed. The intake guide portion 47 is formed by providing an intake port 48 on the peripheral surface 431 of the cylindrical intake portion 43 so as to open a tangential direction of the peripheral surface 431. That is, the intake guide portion 47 includes a tangential guide wall 471 that extends in the tangential direction of the peripheral surface 431 of the cylindrical intake portion 43, and a guide support wall 472 that supports the tangential guide wall 471. Here, an air inlet 48 that is opened by the tangential guide wall 471, and the guide support wall 472 is formed so that the opening direction faces the tangential direction of the peripheral surface 431. The air inlet 48 formed in this way is formed in a slit shape extending along the rotational axis direction of the motor spindle 25.

Inside the device housing 41 formed as described above, a substantially cylindrical airflow guide tube portion 51 having an opening on the front side and the rear side is disposed. The airflow guide tube portion 51 is integrated by adhesively bonding the overlapping portion 52 to the device housing 41. The airflow guide tube 51 is supported with respect to the device housing 41 by the overlapping portion 52 bonded to the device housing 41 in this way. The front end portion of the airflow guide tube portion 51 constitutes a connection portion 50 that is connected to the connection portion 29 of the tool body 15 described above.
The airflow guide cylinder portion 51 corresponds to an airflow guide portion according to the present invention. The air flow guide cylinder portion 51 has a function of guiding the outside air sucked from the intake portion 45 to generate an air flow in the centrifugal separation chamber 55. The airflow guide tube portion 51 is formed by dividing the function into a guide tube portion 53 and a connection tube portion 54 in order from the rear side. The guide cylindrical portion 53 and the connecting cylindrical portion 54 are integrally formed so as to be continuous with each other. The guide cylindrical portion 53 is formed in a cylindrical shape that reduces the inner peripheral diameter toward the rear side. A rear end opening 531 having a cylindrical shape is formed at the rearmost end of the guide cylindrical portion 53. For this reason, the cross-sectional diameter is such that the outside air sucked from the intake portion 45 can be sent to the centrifuge chamber 55 between the guide cylindrical portion 53 and the cylindrical intake portion 43 (device housing 41). An appropriate space is formed in the direction. On the other hand, the connection cylinder part 54 is formed in the cylinder shape protruded to the front side from the apparatus housing 41, and the front-end opening part 541 is formed. The front end opening 541 is connected to the rear side of the motor housing 22 which is also the rear side of the tool body 15.

According to the separation device 40 described above, the function of separating the separated material and the function of discharging the separated material can be exhibited as follows. 10 to 12 are action schematic diagrams schematically showing the action of centrifuging dust and the like (dust and water droplets) mixed in the outside air and the action of discharging the separated material separated by this centrifugation. It is. That is, FIG. 10 is an operation schematic diagram schematically showing the outside air sucked into the separation device 40. FIG. 11 is an operation schematic diagram schematically showing the centrifugal separation inside the separation device 40. FIG. 12 is an operation schematic diagram schematically showing the discharge of the separated matter inside the separation device 40. 10 is a schematic view of the operation in the rear view when viewed along the rotational axis direction of the motor spindle 25. FIGS. 11 and 12 are viewed along the direction intersecting the rotational axis of the motor spindle 25. FIG. It is an operation schematic diagram in the case of a side view.
That is, as described above with reference to FIG. 3, the motor cooling fan 27 that rotates integrally with the motor spindle 25 causes wind to flow from the rear side to the front side inside the tool body 15 by the integral rotation with the motor spindle 25. . That is, the motor cooling fan 27 acts to suck the outside air from the intake portion 45 so as to cool each member constituting the drive motor 23 by rotating. Specifically, as shown in FIG. 10, outside air existing outside the separation device 40 is sucked into the separation device 40 from an intake port 48 that is partitioned and opened by a tangential guide wall 471 and a guide support wall 472. Then, an intake airflow (thick line W1 in FIG. 10) is formed. Here, since four intake portions 45 having the intake ports 48 are arranged at equal intervals with respect to the peripheral surface 431 of the cylindrical intake portion 43, the intake portions 45 are sucked into the cylindrical intake portion 43. The intake airflow (thick line W1 in FIG. 10) is generated at a uniform interval with good balance.

Here, when the outside air sucked from the intake port 48 enters the centrifugal separation chamber 55, the intake guide portion 47 (tangential guide wall 471, guide support wall 472) shown in FIG. The airflow guide cylinder 51 (guide cylinder 53) is guided so as to generate a rotating airflow (thick line W2 in FIG. 11). That is, the rotating airflow (thick line W2 in FIG. 11) formed by the intake guide portion 47 and the airflow guide cylinder portion 51 is guided from the intake port 48 toward the centrifuge chamber 55 (front side in the figure) while being guided by the airflow guide cylinder portion 51. To the rear side of the figure). Here, the rotating airflow (thick line W2) transferred to the centrifuge chamber 55 in this way exhibits a centrifuge function in the centrifuge chamber 55 by this rotation.
That is, as shown in FIG. 11, the rotating airflow (thick line W2) in the centrifugal separation chamber 55 is divided into a relatively heavy dust and the like, and a relatively cool motor cooling air by a centrifugal separation function of the rotating airflow. Acts like centrifuging. Specifically, as shown in FIG. 11, the rotating airflow (thick line W2) that has entered the centrifugal separation chamber 55 removes dust or the like (indicated by the reference symbol D) mixed in the rotating airflow (thick line W2) in the centrifugal separation chamber 55. It acts to press against the inner wall surface 425 so as to stick to the wall surface 425. On the other hand, the airflow that enters the airflow guide cylinder portion 51 from the centrifuge chamber 55 becomes clean air from which dust or the like (denoted D in the figure) scattered on the inner wall surface 425 of the centrifuge chamber 55 is removed. . That is, the rotating airflow (thick line W2 in FIG. 11) that has entered the centrifugal separation chamber 55 acts to remove the outside air mixed with dust and the like toward the tool body 15 as motor cooling air that becomes clean air. Will be sent. Note that this rotating airflow (thick line W2 in FIG. 11) is formed by the intake airflow (thick line W1 in FIG. 10) sucked into the inside of the cylindrical intake portion 43 with a good balance at equal intervals as described above. An airflow rotating in a well-balanced manner inside the cylindrical intake portion 43 can be obtained.

  Incidentally, as shown in FIG. 11, dust or the like (denoted D in the figure) scattered on the inner wall surface 425 of the centrifuge chamber 55 is separated from the above-described intake portion 45 as a separated product in the centrifuge chamber 55. It can be discharged to the outside. In other words, the intake section 45 described above also functions as a discharge section for discharging the separated material separated in the centrifugal separation chamber 55 to the outside. Specifically, the intake port 48 constituting the intake unit 45 functions as a discharge port for discharging the separated material separated in the centrifugal separation chamber 55 to the outside. Further, the inner wall surface 425 of the conical portion 422 facing the centrifugal separation chamber 55 is formed so as to extend in a direction inclined with respect to the horizontal direction when the disc grinder 10 is in a regular stationary posture. For this reason, when the suction of the outside air from the intake portion 45 is stopped, the separated material separated in the centrifugal separation chamber 55 along the direction in which the inner wall surface 425 is inclined is changed to the intake portion by the dead weight of the separated material. It has a discharge guide function that acts to discharge from 45 to the outside. Specifically, as shown in FIG. 12, when the suction of the outside air from the intake section 45 is stopped by the rotation of the motor cooling fan 27, the centrifugal separation function using the above-described rotating air flow (thick line W2 in FIG. 11). The dust or the like (denoted by reference sign D) that has spread on the inner wall surface 425 of the conical portion 422 can be rolled toward the intake portion 45 by the horizontal inclination of the inner wall surface 425 of the conical portion 422. As described above, the dust or the like (reference symbol D) that rolls under its own weight from the inner wall surface 425 that has stuck to the suction portion 45 due to the horizontal inclination of the inner wall surface 425 is automatically transmitted to the outside from the suction port 48 that constitutes the suction portion 45. Will be discharged. Note that, when the outside air is sucked from the intake portion 45 by the rotation of the motor cooling fan 27, dust or the like (indicated by D in the drawing) mixed in the outside air is separated from the conical portion 422 by the centrifugal separation function using the rotating airflow. It remains pressed against the inner wall surface 425.

According to the disc grinder 10 of the first embodiment described above, the following operational effects can be obtained.
That is, according to the disk grinder 10 described above, since the separation device 40 is provided on the outside air suction side of the motor housing 22 that houses the drive motor 23, the motor cooling for cooling the drive motor 23 with the outside air that is sucked in is performed. It can be separated by a centrifugal separation function as wind. As a result, dust or the like (dust or water droplets) mixed in the outside air can be separated to exert a dust removing effect, and the outside air sucked into the disc grinder 10 can be used as a clean motor cooling air. it can. Further, since the dust and the like mixed in the outside air is only separated by the centrifugal separation function of the separation device 40, the dust and the like do not adhere to or accumulate on the intake portion 45. Thereby, the pressure loss at the time of sucking outside air can be eliminated, and the air volume as the motor cooling air can be maintained. Therefore, according to the disc grinder 10 described above, the outside air sucked into the disc grinder 10 as the motor cooling air for cooling the drive motor 23 can be removed, and the dust adhering to the intake portion 45, the dust, etc. The amount of air as motor cooling air can be maintained over a long period of time by avoiding the accumulation of air.

  Further, according to the disc grinder 10 described above, the intake port 48 of the intake unit 45 functions as a discharge port of the discharge unit for discharging the separated material separated in the centrifugal separation chamber 55 to the outside. The separated matter of the sucked outside air separated from the motor cooling air by the centrifugal separation function by 40 can be discharged outside without accumulating in the centrifugal separation chamber 55. This eliminates the need for a storage box for storing the separated air. Therefore, the separation device 40 can be reduced in size, and the disc grinder 10 can be reduced in size. Further, according to the disk grinder 10 described above, the inner wall surface 425 that defines the centrifuge chamber 55 has an inclined structure, so that when the suction of the outside air from the intake portion 45 stops, The separated product can be easily discharged out of the intake port 48 of the intake unit 45 by the weight of the separated product. This eliminates the need for discharge maintenance for discharging the separated product. Accordingly, the disc grinder 10 is easy to use. Further, according to the disk grinder 10 described above, since the outer portion of the separation device 40 functions as a grip of the disk grinder 10, the disk volume can be maintained while the outside air can be removed as the motor cooling air while the disk volume can be maintained. A function as a grip of the grinder 10 is also added. That is, the separation function of the disc grinder 10 can also be used as the separating device 40, and the disc grinder 10 can be made compact.

  Further, according to the disc grinder 10 described above, the airflow guide cylinder portion 51 that guides the outside air sucked from the intake portion 45 so as to generate an airflow in the centrifugal separation chamber 55 is provided inside the apparatus housing 41. Therefore, the degree of freedom in selecting the shape of the outer portion of the device housing 41 can be increased. Thereby, the shape selection width in forming the grip shape on the outer portion of the separating device 40 can be expanded. Further, according to the disc grinder 10 described above, the four intake portions 45 are arranged at intervals with respect to the peripheral surface 431 of the device housing 41, so that an intake region for sucking outside air is secured. It is possible to secure air volume. Further, in the case where the intake portion 45 is caused to function as a discharge portion that discharges the separated material, a discharge region for discharging the separated material can be secured in a plurality of directions. As a result, it is possible to ensure the function of discharging the separated matter regardless of the posture of the disc grinder 10 while ensuring the air volume for cooling the drive motor 23. Further, according to the disk grinder 10 described above, the disposition position of the intake portion 45 is set at a position facing the circumferential direction 431 of the device housing 41 in the normal stationary posture of the disk grinder 10 in the direction of gravity. When the intake portion 45 is caused to function as a discharge portion in the regular stationary posture of the disc grinder 10, it is possible to facilitate discharge from the intake portion 45 to the outside due to the weight of the separated matter. Thereby, the function for discharging the separated product of the disc grinder 10 in the regular stationary posture can be further enhanced. Further, according to the disk grinder 10 described above, since the separation device 40 is configured to be removable from the motor housing 22, the motor housing 22 can use a conventional configuration. Thus, the configuration other than the separation device 40 can be configured as before.

[Second Embodiment]
Next, a second embodiment for carrying out the electric tool according to the present invention will be described. The second embodiment described below is different from the first embodiment described above with respect to the configuration of the separation device 40 attached to the tool body 15. Therefore, in the second embodiment described below, only the configuration of the separation device 40A will be described with reference to FIGS. 13 to 15 are action schematic diagrams corresponding to FIGS. 10 to 12 in the description of the first embodiment. That is, FIG. 13 is a schematic operation diagram schematically illustrating the outside air sucked into the separation device 40A according to the second embodiment. FIG. 14 is a schematic view showing the operation of the centrifugal separator 40A in FIG. 13 schematically. FIG. 15 is an operation schematic diagram schematically showing discharge of the separated matter inside the separation device 40A of FIG. In the separation apparatus 40A according to the second embodiment, the same components as those of the separation apparatus 40 according to the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. .
The separation device 40A according to the second embodiment is different from the separation device 40 according to the first embodiment in the arrangement structure of the intake portion 45A (intake guide portion 47A). That is, the intake guide 47 of the separation device 40 according to the first embodiment is provided outside the housing opening 46, but the intake guide of the separation device 40A according to the second embodiment. The portion 47A is provided inside the housing opening 46. That is, in the separation device 40A of the second embodiment, the intake guide portion 47A is provided on the inner side of the peripheral surface 431 of the cylindrical intake portion 43, as compared with the separation device 40 of the first embodiment. In addition, the outside air sucked into the centrifuge chamber 55 through the intake portion 45A is sucked so as to become a rotating airflow (thick line W2 in FIG. 12) that exhibits a centrifuge function in the centrifuge chamber 55. The points agree.

Specifically, the intake guide portion 47 </ b> A also enters the inside of the device housing 41 where the sucked outside air generated by the rotation of the motor cooling fan 27 enters from the tangential direction of the peripheral surface 431 of the cylindrical intake portion 43. Designed. The intake guide portion 47A is formed by providing an intake port 48A on the peripheral surface 431 of the cylindrical intake portion 43 so as to open a tangential direction of the peripheral surface 431. In other words, the intake guide portion 47A includes a tangential guide wall that extends in the tangential direction of the peripheral surface 431 of the cylindrical intake portion 43, 471A, and a guide support wall 472A that supports the tangential guide wall 471A. Here, the air inlet 48 </ b> A opened by the tangential guide wall 471, and the guide support wall 472 is formed so that the opening direction faces the tangential direction of the peripheral surface 431. The intake port 48 </ b> A formed in this way is also formed in a slit shape extending along the rotational axis direction of the motor spindle 25.
Even when the separation device 40A of the second embodiment is replaced with the separation device 40 of the first embodiment and the disc grinder 10 is configured, a centrifugal separation function for separating the separated material and a function for discharging the separated material are provided. The same effects as in the first embodiment described above can be obtained. Furthermore, according to the second embodiment, the intake guide portion 47A is provided on the inner side of the peripheral surface 431 of the cylindrical intake portion 43, so that it can be compared with the first embodiment. The protrusion amount of the intake guide portion 47A from the peripheral surface 431 of the cylindrical intake portion 43 can be eliminated. That is, when the outer portion of the separating device 40 is caused to function as a grip of the disc grinder 10, it can be grasped along the shape of the peripheral surface 431 of the cylindrical intake portion 43. As a result, it is possible to improve the feel when the outer portion of the separation device 40 is gripped as a grip.

In addition, in the electric tool which concerns on this invention, it is not limited to above-described embodiment, You may make it change and comprise suitably as follows.
For example, in the above-described embodiment, the disk grinder 10 is described as an example of a hand-held power tool. However, the hand-held electric tool according to the present invention is not limited to this, and a drive motor driven by power supply such as a hand-held electric jigsaw or a hand-held electric reciprocating saw is used as a power source. Any hand-held power tool can be used.
Further, in the disc grinder 10 of the above-described embodiment, the built-in motor cooling fan 27 is constituted by a centrifugal blower fan that blows air in the centrifugal direction. However, the motor cooling fan according to the present invention is not limited to this, and may be an axial-flow fan that blows air in the rotation axis direction.
Further, the separation devices 40 and 40A of the above-described embodiment are configured to include the device housing 41, the centrifugal separation chamber 55, and the intake portions 45 and 45A. However, the separation device according to the present invention is not limited to this, and employs an appropriate configuration for separating the outside air sucked into the outside air suction side into a motor cooling air for cooling the motor by a centrifugal separation function. be able to.

  Further, the intake section of the separation apparatus according to the present invention is not limited to the examples of the intake sections 45 and 45A of the above-described embodiment, and is provided on the peripheral surface of the apparatus housing and sucks outside air into the centrifuge chamber. And what is necessary is just to function as a discharge part for discharging the isolate | separated material isolate | separated in the centrifuge chamber outside. In the separation devices 40 and 40A according to the above-described embodiment, the outside air sucked from the intake portion 45 is separated into the motor cooling air and the dust (such as dust and water droplets) described above. However, the separation device according to the present invention may separate water such as water droplets from the outside air sucked from the intake portion and send it to the tool body as motor cooling air. Further, the discharge guide shape according to the present invention is not limited to the example of the inner wall surface 425 of the conical portion 422 of the above-described embodiment, and when the suction of the outside air from the intake portion is stopped, An appropriate shape can be selected as long as it has a function of discharging the separated product by the dead weight of the separated product. Further, an anti-slip function for improving the grip performance as the disc grinder 10 may be provided on the outer portion of the separating devices 40 and 40A.

Further, four intake portions 45, 45A provided in the separation devices 40, 40A of the above-described embodiment are arranged at equal intervals with respect to the peripheral surface 431 of the cylindrical intake portion 43 (device housing 41). It was a thing. However, the intake portions according to the present invention are not limited to this, and for example, three intake portions may be arranged at appropriate intervals. In other words, the air intake section according to the present invention is only required to have a preferable area for generating the rotating airflow while ensuring the air volume as the motor cooling air, and further from the air intake section due to the weight of the separated object. It is preferable that it is designed to be easily discharged.
In addition, the intake portions 45 and 45A provided in the separation devices 40 and 40A according to the above-described embodiment are configured to be removable from the motor housing 22 serving as a main body housing of the tool main body 15. However, the separation device according to the present invention is not limited to this, and may be formed by integral molding with a motor housing serving as a main body housing.

10 Disc grinder (electric tool)
DESCRIPTION OF SYMBOLS 15 Tool main body 18 Cover body 20 Power generation part 22 Motor housing 23 Drive motor (power source)
24 Bearing 25 Motor spindle (Rotating shaft)
27 Motor cooling fan 29 Connection portion 30 Power conversion portion 32 Gear housing 33 Drive side gear 35 Drive side gear 37 Output spindle 38 Bearing 39 Exhaust port 40, 40A Separating device 41 Device housing 42 Conical bottom portion 421 Bottom portion 422 Conical portion 425 Inner wall surface (Wall surface of the partition wall)
43 Cylindrical air intake portion 431 Peripheral surface 45, 45A Air intake portion 46 Housing opening portion 47, 47A Air intake guide portion 471, 471A Tangential guide wall 472, 472A Guide support wall 48, 48A Air intake port 50 Connection portion 51 Airflow guide cylinder portion (air flow Guide part)
52 Superposition part 53 Guide cylindrical part 531 Rear end opening part 54 Connection cylinder part 541 Front end opening part 55 Centrifugal separation chamber B Grinding wheel

Claims (8)

A hand-held electric tool comprising: a drive motor as a power source; and a motor cooling fan that is attached to a shaft that is rotated by the drive motor so as to be integrally rotatable and sucks outside air,
A power tool characterized in that a separating device for separating the sucked outside air into motor cooling air for cooling the motor by a centrifugal separation function is provided on the outside air suction side of the main body housing that houses the drive motor. The power tool according to claim 1,
The separation device includes a device housing in which a centrifuge chamber that exhibits a centrifuge function is formed while forming an exterior, and an outside air that is provided on a peripheral surface of the device housing and is directed toward the centrifuge chamber With an air intake,
The electric power tool characterized in that the intake section functions as a discharge section for discharging the separated material separated in the centrifugal separation chamber to the outside. In the electric tool according to claim 2,
When the suction of the outside air from the air intake section stops, the separated material separated in the centrifugal chamber is separated from the air intake section by the dead weight of the separated material. An electric power tool characterized in that a discharge guide shape acting so as to discharge is provided. In the electric tool according to any one of claims 1 to 3,
An electric tool characterized in that an outer portion of the separating device functions as a grip of the electric tool. In the electric tool according to claim 4,
An electric power tool characterized in that an airflow guide portion that guides outside air sucked from the intake portion so as to generate an airflow in the centrifugal separation chamber is provided inside the device housing. In the electric tool according to any one of claims 2 to 5,
The power tool according to claim 1, wherein a plurality of the air intake portions are arranged at intervals with respect to the peripheral surface of the device housing. In the electric tool according to any one of claims 2 to 6,
The position of the intake portion disposed on the peripheral surface of the device housing is set to a position facing the direction of gravity with respect to the peripheral surface of the device housing in the regular stationary posture of the electric tool. A featured electric tool. In the electric tool according to any one of claims 1 to 7,
The power tool, wherein the separation device is configured to be removable from the main body housing.

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