JP2912564B2 - Portable rotating tools - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable rotary tool capable of discharging cutting chips in a predetermined direction from the inside of a safety cover covering a circular saw blade.

[0002]

2. Description of the Related Art Conventionally, as a portable rotary tool for discharging cutting chips in a predetermined direction from the inside of a safety cover covering a circular saw blade, Japanese Utility Model Laid-Open No. 1-70505 and Japanese Utility Model Laid-Open No. 5-35 are known.
No. 203 and Japanese Utility Model Laid-Open No. 4-83705.

[0003] The portable rotary tool disclosed in Japanese Utility Model Laid-Open No. 1-70505 is provided with a large number of ribs on an inner peripheral surface of a safety cover, and collides cutting ribs with these ribs so as to be directed out of the safety cover. is there.

In the portable rotary tool disclosed in Japanese Utility Model Laid-Open No. 5-35203, a single rib is provided on the inner peripheral surface of the safety cover from the front part to the center part, and the rib guides cutting chips outside the safety cover. What you want to do.

In the portable rotary tool disclosed in Japanese Utility Model Application Laid-Open No. 4-83705, a discharge port is formed in the rear portion of the safety cover, and cutting chips flowing along the inner peripheral surface of the safety cover are discharged from the safety cover through the discharge port. It is trying to discharge to the outside.

[0006]

However, in the conventional chip discharging structure disclosed in Japanese Utility Model Laid-Open No. 1-70505, a part of the cutting chips hits the ribs and exits from the side of the safety cover. Since there is a relatively large gap between the safety cover and the lower guard, there is an inconvenience that other debris flows from the gap to the rear of the safety cover and is discharged to the operator.

In the portable rotary tool disclosed in Japanese Utility Model Application Laid-Open No. 5-35203, cutting chips are discharged from the front to the center of the safety cover. There is a problem that debris scatters and accumulates, making it difficult to confirm the cutting position and direction.

The portable rotary tool disclosed in Japanese Utility Model Laid-Open No. 4-83705 can discharge cutting chips from the discharge port of the safety cover, but a relatively large gap still exists between the safety cover and the lower guard. There is an inconvenience that some cuttings flow from the gap to the rear of the safety cover and are discharged toward the operator.

Therefore, the present invention can prevent the chips from being directed toward the worker when discharging the chips outside the safety cover, and can prevent a large amount of chips from accumulating on the processing portion from the beginning of cutting. An object is to provide a portable rotary tool.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a housing 1 in which an electric motor for rotating a circular saw blade 5 is built, and an upper part of the circular saw blade 5 attached to the housing 1. A lower cover 4 for covering a lower portion of the circular saw blade 5 supported by the housing 1 so as to rotate into the safety cover 2 as the workpiece is cut. In a portable rotary tool provided with a base 3 for abutting on a workpiece attached to the housing 1 or the safety cover 2, an outer peripheral surface 4a of the lower guard 4 and an inner peripheral surface 2a of the safety cover 2 are formed. The outward projection 6 that blocks the gap between the lower guard 4
The outer projection 4 is provided at the rear of the outer peripheral surface 4a, and is connected to the outward projection 6 from the housing side to the opposite housing side.
And a guide surface 6a for guiding the cutting chips inclined toward the base 3 toward the opposite side of the housing is adopted. In the portable rotary tool, the cutting chips are formed toward the rear end of the safety cover 2. A rib 7 for preventing flow is provided on the inner peripheral surface 2a of the safety cover 2, and in the portable rotary tool, a rib 7 is provided on the rear end of the inner peripheral surface 4b of the lower guard 4. An orientation protrusion 8 is provided, and the guide surface 8a of the chip in the inward protrusion 8 is formed to guide the chip to the side opposite to the housing.

[0011]

In order to cut a workpiece with this portable rotary tool, an electric motor is started, the base 3 is applied to the workpiece, and the front of the circular saw blade 5 is indicated by a black line, for example, of the workpiece. Applied to the cut location. As the cutting progresses, the front part of the lower guard 4 is pressed by the workpiece and the safety cover 2 is pressed.
Swivels in. Also, cutting chips generated by cutting are
It flows along the inner peripheral surface of the safety cover 2 and hits the outward projection 6 located at the rear of the outer peripheral surface of the lower guard 4. Since the outward projection 6 blocks the gap between the outer peripheral surface 4a of the lower guard 4 and the inner peripheral surface 2a of the safety cover 2, the cutting chips do not flow out to the worker behind the safety cover 2. The cuttings that have hit the outward projection 6 are guided by the guide surface 6 a to the opposite side of the housing 1 and are discharged from the side surface of the safety cover 2. At the beginning of cutting, the rear part of the lower guard 4 is located at a position near the rear part in the safety cover 2 and is away from the position where the circular saw blade 5 cuts the work material. . Therefore, appropriate cutting can be performed while checking the black line.

When a rib 7 is provided on the inner peripheral surface 2a of the safety cover 2 according to the present invention, the rib 7 kills the flow of cutting chips and the flow of the cutting chips together with the outward projection 6 reduces the flow of cutting chips. To the side.

In the present invention, the outward projection 6
At the same time, an inward projection 8 is provided at the rear end of the inner peripheral surface 4b of the lower guard 4, and the guide surface 8a for the cutting chips on the inward projection 8 is formed to guide the cutting chips to the opposite side of the housing. The areas of the guide surfaces 6a and 8a are enlarged, so that cutting chips can be more appropriately directed to the side surface of the safety cover 2.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 As shown in FIG. 1, this portable rotary tool is a portable circular saw, specifically, a housing 1 in which an electric motor for rotating a circular saw blade 5 is built, and Safety cover 2 for covering the upper part of the attached circular saw blade 5
And the circular saw blade 5 supported by the housing 1 so as to rotate into the safety cover 2 as the workpiece is cut.
A lower guard 4 for covering the lower part of the housing 1 and the housing 1
Or a base 3 attached to the work material attached to the safety cover 2.

In cutting the workpiece by the portable rotary tool, the electric motor is started, the circular saw blade 5 is rotated at a predetermined number of revolutions, and the base 3 is applied to the workpiece. The circular saw blade 5 is applied to a cut portion of the workpiece, for example, indicated by a black line, and the cutting by the circular saw blade 5 proceeds as the base 3 is slid over the workpiece. Further, as the cutting proceeds, the lower guard 4 rotates into the safety cover 2 while being pressed by the workpiece.

The cutting chips generated by the portable rotary tool flow from the front to the rear along the inner peripheral surface of the safety cover 2, but flow out of the rear end of the safety cover 2 and thereafter. Fig. 2
As shown in FIG. 4, an outward projection 6 that shields a gap between the outer peripheral surface of the lower guard 4 and the inner peripheral surface of the safety cover 2 is provided at the rear of the outer peripheral surface 4 a of the lower guard 4.
Is provided. The outward projection 6 is formed with a guide surface 6a for guiding cutting chips toward the side opposite to the housing. In addition, the rear part of the lower guard 4 indicates a part in which the workpiece is not cut (FIG. 1) and is covered with the safety cover 2 as shown in FIG.

The outward projection 6 is specifically formed on the safety cover 2.
Projecting in a radial direction of the lower guard 4 so as not to contact the inner peripheral surface of the lower guard 4, and is inclined in the direction of the base 3 from the housing side to the opposite side on the outer peripheral surface 4 a of the lower guard 4.

However, cutting chips generated by cutting are:
It flows in the direction of the arrow b along the inner peripheral surface of the safety cover 2 and hits the outward projection 6 at the rear of the outer peripheral surface 4 a of the lower guard 4. Since the outward projection 6 shields a gap between the outer peripheral surface 4a of the lower guard 4 and the inner peripheral surface 2a of the safety cover 2,
The cutting chips are prevented from advancing to the rear end of the safety cover 2, guided to the opposite side of the housing 1 by the guide surface 6 a of the outward projection 6, and discharged from the side of the safety cover 2 opposite the housing 1 to the outside of the safety cover 2. Will be done. Further, as shown in FIG. 2, the portion after the cutting beginning Roagado 4 There are circular saw blade 5 on the rear side of the position in the safety cover 2 away from the point of cutting the workpiece, cutting chips Does not accumulate on the cutting position of the workpiece. Therefore, appropriate cutting can be performed while checking the black line.

Embodiment 2 As shown in FIGS. 5 and 6, in this portable rotary tool, a rib 7 for preventing cutting chips from flowing toward the rear end of the safety cover 2 is provided with the safety cover. 2 is provided on the inner peripheral surface 2a.

The peripheral wall of the safety cover 2 bulges outward at a portion near the rear portion thereof, and a number of ribs 7 project radially inside the bulged portion. These ribs 7 are formed so that the tips do not contact the outward projections 6 of the lower guard 4. The rib 7 is 1
It may be a sheet.

As a result, the cutting chips flowing along the inner peripheral surface 2a of the safety cover 2 collide with the ribs 7 and lose their momentum. Then, the flow direction b is changed to the side surface of the safety cover 2 by the outward projection, and the flow is discharged from the side surface of the safety cover 2 to the outside.

Embodiment 3 As shown in FIGS. 7 and 8, in this portable rotary tool, an inward projection 8 is provided at the rear end of the inner peripheral surface 4b of the lower guard 4. The inward projection 8 is inclined in the same direction as the outward projection 6 provided on the rear end of the lower guard 4, and furthermore, the guide surface 8 a for cutting chips on the inward projection 8.
Are connected to the guide surface 6a of the outward projection 6 and are flush with each other.

The inward projection 8 is a substantially U-shaped plate, and the cutting edge of the circular saw blade 5 passes through the center notch 9. In this embodiment, the guide surface 6a of the outward projection 6 and the guide surface 8a of the inward projection 8 are flush, but the outward projection 6 is lowered from the rear end of the lower guard 4 to the base 3 side. The lower guard 4 may not be provided flush with the inward projection 8 provided at the rear end of the inner peripheral surface 4b of the lower guard 4.

Thus, the area of the guide surfaces 6a and 8a for the cutting chips is enlarged, and the flow direction b of the cutting chips is more appropriately changed to the side surface of the safety cover 2, so that the safety cover 2
Will be discharged from the side of the container.

[0025]

According to the present invention, the flow of the cutting chips generated by cutting to the rear end of the safety cover is blocked by the outward projection, and the guide surface of the outward projection is directed to the side of the safety cover opposite to the housing. The direction of the flow can be changed. Therefore, it is possible to reliably prevent the cutting chips from flowing out from the rear end of the safety cover. Further, since the outward projection is located at the rear part of the lower guard, it is located at a position near the rear part in the safety cover at the beginning of cutting, and is separated from the cutting part by the circular saw blade. Therefore, it is possible to prevent cutting chips from accumulating on the cutting position, and to easily confirm the position and the direction of the black line to perform appropriate cutting.

In the present invention, when a rib is provided on the inner peripheral surface of the safety cover, the rib kills the flow of the cutting waste and directs the flow of the cutting waste together with the outward projection toward the side surface of the safety cover. Scattering of cutting chips from the rear end of the cover can be prevented.

Further, in the present invention, when an inward projection is provided at the rear end of the inner peripheral surface of the lower guard together with the outward projection, the area of the guide surface is enlarged, and cutting chips are more appropriately removed. It can be prevented from scattering from the rear end of the safety cover toward the side.

[Brief description of the drawings]

FIG. 1 is a perspective view of a portable rotary tool according to the present invention.

FIG. 2 is a partially cutaway side view of a main part of the portable rotary tool.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a view of the lower guard in FIG.

FIG. 5 is a partially cutaway side view showing a main part of another embodiment of the portable rotary tool according to the present invention.

6 is a sectional view taken along line VI-VI in FIG.

FIG. 7 is a partially cutaway side view showing a main part of another embodiment of the portable rotary tool according to the present invention.

FIG. 8 is a view of the lower guard taken along line VIII in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Housing 2 ... Safety cover 2a ... Inner peripheral surface of a safety cover 3 ... Base 4 ... Lower guard 4a ... Outer peripheral surface of a lower guard 4b ... Inner peripheral surface of a lower guard 5 ... Circular saw blade 6 ... Outward projection 6a ... Guide of cutting waste Surface 7: rib 8: inward projection 8a: guide surface for cutting chips

Claims (3)

(57) [Claims] 1. A housing in which an electric motor for rotating a circular saw blade is built, a safety cover for covering an upper portion of the circular saw blade attached to the housing, and a safety cover for cutting a work material. A portable device comprising a lower guard for covering a lower portion of the circular saw blade supported by the housing so as to rotate toward the housing, and a base for abutting a workpiece attached to the housing or the safety cover. In the rotating tool, an outward projection that shields a gap between an outer peripheral surface of the lower guard and an inner peripheral surface of the safety cover is provided at a rear portion of an outer peripheral surface of the lower guard, and the outward projection includes the housing. From side to opposite housing side
A portable rotary tool having a guide surface for guiding cutting chips inclined toward the base toward the opposite side of the housing. 2. The portable rotary tool according to claim 1, wherein a rib for preventing cutting chips from flowing toward the rear end of the safety cover is provided on an inner peripheral surface of the safety cover. 3. An inward projection is provided at a rear end of an inner peripheral surface of the lower guard, and a guide surface of the chip on the inward projection is formed to guide the chip toward the opposite side of the housing. The portable rotary tool according to claim 1 or 2, wherein