JP2002283255A - Power tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent intrusion of dust with the simple constitution without having influence on a using feeling and a shape of a motor housing. SOLUTION: A cylindrical mesh cover 10 having the rear end openable- closable by hook-and-loop fasteners 11 and 11 is out-fitted in a close contact state to the motor housing 2 for boring cooling air introducing ports 7, 7, etc., and is integrated with the motor housing 2 by welding of plural places.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power tool such as a grinder having a cooling air inlet formed in a motor housing.

[0002]

2. Description of the Related Art In a power tool, a fan is fixed to an output shaft of a motor. On the other hand, a cooling air inlet is provided on an upstream side of the fan and a cooling air outlet is provided on a downstream side of the motor. A structure is employed in which a motor is cooled by taking out outside air from an inlet, passing through the inside of a motor housing, and exhausting from an outlet by rotation of a fan accompanying rotation of an output shaft.

[0003]

However, if the power tool generates dust or cutting debris when using a grinder or the like, the dust or the like is sucked in when the cooling air is taken into the motor housing and introduced. The mouth and the motor may be clogged. Therefore, a structure is used in which a filter is provided at an inlet portion of the outer surface of the motor housing to prevent dust and the like from entering (for example, Japanese Utility Model Publication No. 53-492).
No. 01 and Japanese Unexamined Utility Model Publication No. 2-85559), since these have a form in which the inlet is provided only at the tail of the motor housing, it is not possible to cope with a case where a large number of inlets are provided including the side of the motor housing. However, if a separate filter is provided, the motor housing becomes uneven, making it difficult to grip the motor housing. Although it is conceivable to provide a filter on the inner surface side of the motor housing, the motor housing becomes large in order to secure a space for providing the filter.

Accordingly, the first aspect of the present invention is to effectively prevent dust and the like from invading with a simple configuration even with a large number of inlets without impairing usability or increasing the size of the motor housing. It is an object of the present invention to provide a power tool capable of performing the following.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, a motor housing is integrally and closely contacted with a cover provided with a filter at least in a portion corresponding to an inlet. It is characterized by being coated. The invention according to claim 2 has, in addition to the object of claim 1, a structure in which the entire cover is formed by a mesh and welded to the motor housing in order to easily and reliably cover the motor housing. It is. The invention described in claim 3 provides, in addition to the object of claim 1, to make cleaning, cleaning and replacement of the filter convenient.
The cover is detachable from the motor housing.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. << Form 1 >> FIG. 1 is an overall view of a grinder. The grinder 1 is connected to a main body housing 3 containing a well-known deceleration mechanism in front of a motor housing 2 containing a motor (left side in the figure). A cover 4 for pivotally supporting a spindle 5 is connected to the front of the motor housing 2 and the main body housing 3 in a direction orthogonal to the motor housing 2. It can be fixed. As shown in FIG. 2, cooling air inlets 7, 7,... Are formed in the front, left and right side surfaces and the rear surface of the motor housing 2, respectively. The air outlets 8, 8,... Reference numeral 9 denotes a power cord drawn from the rear surface of the motor housing 2.

On the other hand, the motor housing 2 is covered with a mesh cover 10 from behind. As shown in FIG. 2, the mesh cover 10 is a tubular body sewn so as to wrap around the outer surface of the motor housing 2 in close contact with the mesh cover 10. It is formed with a length that extends slightly backward,
The motor housing 2 is welded at several places in the circumferential direction near the main body housing 3 and at several places in the circumferential direction while moving backward at equal intervals (positions indicated by X in FIG. 2; here, a total of 16 places). Are integrated. The reason why the welding is performed in the circumferential direction is to effectively prevent the displacement of the mesh cover 10 and reliably integrate the mesh cover 10 with the motor housing 2. The rear end of the mesh cover 10 is opened to secure the draw-out of the power cord 9 and the operation of the switch 2a provided on the rear surface of the motor housing 2; 11 and 11 are provided so that the rear end opening can be arbitrarily closed except for the power cord 9.

In the grinder 1 constructed as described above, when performing the polishing operation, when the rear end of the mesh cover 10 is opened and the switch 2a is operated to drive the motor, the spindle 5 rotates and the disk shape is formed. The grindstone 6 is rotated. After the switch 2a is operated, the hook-and-loop fasteners 11, 11
To close the rear end of the mesh cover 10. When the motor is driven in this manner, cooling air is taken into the motor housing 2 from the inlets 7, 7,... By the rotation of the fan provided on the motor shaft, and passes through the motor housing 2, the main body housing 3, and the cover 4. Outlet 8,
8. The motor is cooled by being exhausted from. Since the inlets 7, 7,... Of the motor housing 2 are all covered by the mesh cover 10, even if dust is generated during the polishing operation, the dust is blocked by the mesh cover 10, and only the cooling air is meshed. It will pass through the cover 10.

As described above, according to the first embodiment, since the motor housing 2 is integrally and tightly covered with the mesh cover 10, it is possible to effectively prevent dust and the like from entering with a simple configuration. In addition, since the entire motor housing 2 is covered with the thin mesh cover 10, even if the number of the inlets 7 is large, the motor housing 2 does not have irregularities, so that the usability of the grinder 1 is not impaired. Also, the size of the motor housing 2 does not increase.
Especially here, the whole cover is formed by mesh,
Since it is welded to the motor housing 2, the inlet 7 can be easily covered with the mesh without considering the directionality, and the integration with the motor housing 2 is ensured. The rear end of the mesh cover 10 may be completely closed if the power cord 9 and the switch 2a are not provided in the motor housing 2.

Hereinafter, another embodiment of the present invention will be described.
Note that the same reference numerals as in the first embodiment denote the same components, and a duplicate description will be omitted. << Mode 2 >> In FIG. 3, belts 12a and 12b are sewn and fixed along the circumferential direction around the front end of the mesh cover 10, and a ring 13 having an opening having substantially the same width as the belt 12a is fixed to the belt 12a. Attached, belt 12b
Has a free end 14 that can pass through the ring 13.
A surface fastener 15 is provided on the surface of the belt 12b. On the other hand, thin rubbers 16, 16,... Are adhered to the inner circumference of the front end of the mesh cover 10 along the circumferential direction.
A plurality of rubbers 17, 17,... Are also adhered to the inner surface portion of the mesh cover 10 which contacts the outer surface other than 7.

Therefore, in the second embodiment, the outer end of the belt 12b is
After passing the belt 4 through the ring 13, the belt 12 a and 12 b reduce the opening at the front end of the mesh cover 10 and tighten the front end of the motor housing 2 when the belt is turned back and pulled in the circumferential direction away from the ring 13. In this state, if the folded surface fastener 15 of the free end 14 is attached to the same surface fastener 15 on the base end side, as shown in FIG.
Is mounted on the motor housing 2. At this time, slip is prevented by the rubbers 16, 17,... On the inner surface of the mesh cover 10, and the mesh cover 10 and the motor housing 2 are prevented from slipping.
Are integrated. As described above, in the second embodiment, similarly to the first embodiment, by covering the motor housing 2 with the mesh cover 10, effective dust and the like can be obtained without impairing the usability of the grinder 1 and without increasing the size of the motor housing 2. Thus, the effect of preventing the intrusion of the air can be obtained.
Particularly, in this case, since the mesh cover 10 is detachable by the belts 12a and 12b, the mesh cover 10
If dust etc. is clogged, remove it for cleaning or cleaning.
Alternatively, replacement can be easily performed, which is convenient.

<Embodiment 3> The mesh cover 10 shown in FIG. 5A does not use welding, a belt, rubber, or the like, and except for the switch 2a and the power cord 9 at the rear end (by opening the corresponding portion). ), A simple bag-like shape that is externally attached to the motor housing 2, and a guard 18 is used to fix the mesh cover 10. The guard 18 is a thin frame 1 that is arranged in the circumferential direction and the axial direction according to the outer shape of the motor housing 2 except for the introduction ports 7, 7,.
9 and 19, and a plurality of projections 20,
20 are provided. On the other hand, on the outer periphery of the front end of the motor housing 2, as shown in FIG.
Are formed in the circumferential direction. Therefore, here, if the guard 18 is provided on the motor housing 2 on which the mesh cover 10 is provided,
The projections 20, 20,... Engage with the recesses 21, 21,.
By pressing 0 from the outside, the motor housing 2 and the mesh cover 10 are integrated.

As described above, in the third embodiment, similarly to the second embodiment, the motor housing 2 having the mesh cover 10 is used.
Has the effect of effectively preventing intrusion of dust and the like without impairing the usability of the grinder 1 and without increasing the size of the motor housing 2. In addition, since the mesh cover 10 is detachable by using the guard 18, when dust or the like is clogged in the mesh cover 10, it can be easily removed for cleaning, cleaning, or replacement, which is convenient. .

FIG. 6A is a development view of a cover sheet 22 used in place of the mesh cover 10.
An auxiliary portion 24 capable of covering the rear surface of the motor housing 2 except for the switch 2a and the power supply cord 9 is provided at the center lower edge of the belt-shaped main body portion 23 capable of covering substantially the entire surface of the motor housing 2 in the circumferential direction. A pair of belt-like portions 25, 25 extend from lower left and right edges of the auxiliary portion 24.
In the main body 23 and the auxiliary part 24, windows 26, 26,... Are formed in portions corresponding to the inlets 7, 7,. It is stuck. Further, an adhesive is applied to the inner surface of the cover sheet 22 other than the window 26.
Therefore, here, the motor housing 2 of the grinder 1 is set on the main body portion 23 of the spread cover sheet 22 with the inlet 7 aligned with the window 26, and the main body portion 2 is left as it is.
3 is wound around the motor housing 2 and adhered,
Similarly, if the auxiliary portion 24 is attached to the rear surface of the motor housing 2 and finally the belt-like portions 25, 25 are attached to the rear surface of the motor housing 2 on both sides of the power cord 9, FIG.
As shown in the figure, the motor housing 2 is covered with the mesh sheet 27 so that the inlets 7, 7,...
2 will be coated.

As described above, in the fourth embodiment, the second and third embodiments
As in the case of 3, the adoption of the cover sheet 22 has an effect that it is possible to effectively prevent intrusion of dust and the like without impairing the usability of the grinder 1 and without increasing the size of the motor housing 2.

In the above description, a mode in which welding, rubber, and an adhesive are applied independently is described. However, by appropriately combining them (for example, a combination of welding and rubber, a combination of rubber and an adhesive, etc.), a motor may be used. The cover may be closely attached to the housing and may be integrated. The power tool is not limited to a grinder, and the present invention can be applied to other power tools such as a sander as long as the motor housing has an inlet for cooling air. Therefore, the shape of the cover is not limited to the above-described embodiment, and is determined according to the motor housing of the power tool to be applied.

[0017]

According to the first aspect of the present invention, the motor housing is covered with the cover provided with the filter at least at the portion corresponding to the inlet so as to be in close contact with and integrated with the motor housing. It is possible to prevent dust and the like from entering the apparatus. In addition, since the motor housing is covered with a cover, the motor housing does not have irregularities even if there are many inlets, so that the usability of the power tool is not impaired, and the motor housing becomes large. Nor. According to the second aspect of the invention, in addition to the effect of the first aspect, the entire cover is formed of a mesh and is welded to the motor housing, so that it can be easily introduced without considering the directionality. Can cover the mouth part,
Integration with the motor housing is also ensured. According to the third aspect of the invention, in addition to the effect of the first aspect, since the cover is detachable from the motor housing, it is easy to clean, clean, and replace the filter.

[Brief description of the drawings]

FIG. 1 is an overall view of a grinder according to a first embodiment.

FIG. 2A is a left side view of the motor housing with a mesh cover welded thereto. (B) It is a front view of the motor housing which welded the mesh cover. (C) It is a right view of the motor housing which welded the mesh cover. (D) It is a rear view of the motor housing to which the mesh cover was welded. (E) It is sectional explanatory drawing which shows the sewing structure of a mesh cover.

FIG. 3 is a perspective view of a mesh cover according to a second embodiment.

FIG. 4 is an explanatory diagram showing an attached state of a mesh cover.

FIG. 5A is a perspective view of a mesh cover and a guard according to a third embodiment. (B) It is explanatory drawing which shows the attachment state of a mesh cover and a guard.

FIG. 6A is a development view of a cover sheet according to a fourth embodiment. (B) It is explanatory drawing which shows the state covered with the cover sheet.

[Explanation of symbols]

1. Grinder, 2. Motor housing, 3. Body housing, 7. Inlet, 8. Outlet, 10.
Mesh cover, 12a, 12b, belt, 16, 1
7. Rubber, 18 guard, 19 frame, 22 cover sheet, 27 mesh sheet.

Claims (3)

[Claims] 1. A power tool having a plurality of cooling air inlets formed in a motor housing, wherein the motor housing is in close contact with and integrated with a cover provided with a filter at least in a portion corresponding to the inlet. An electric tool characterized by being coated. 2. The whole cover is formed by a mesh,
The power tool according to claim 1, wherein the power tool is welded to the motor housing. 3. The power tool according to claim 1, wherein the cover is detachable from the motor housing.