JPH0545404B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust collection mechanism for a portable power tool.

Cutting wood, stone, etc. using portable power tools,
As a method of collecting and accumulating cutting waste and cutting dust (hereinafter referred to as dust) generated during cutting,
The dust bag method is commonly used.

In the dust bag method, a cloth bag (hereinafter referred to as a dust bag) is connected to the dust outlet of a power tool, and the dust cut by a rotating blade is forced into the dust bag along with airflow by a dust fan. However, this method had the disadvantage that fine dust could leak through the dust bag.

The present invention provides a novel dust collection mechanism for a portable power tool that eliminates the drawbacks of the prior art described above.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS. 1 to 7, using an embodiment of a portable electric circular saw.

Power is transmitted from an electric motor built in the housing to a portable electric circular saw rotary tool 4 attached to a spindle 9 with a washer 10 and a fixing bolt 11 via a transmission means such as a gear (not shown).
When cutting is performed using a portable electric circular saw with the base 3 fixed at an arbitrary position by loosening the tightening screw 12, the cutting dust is removed by the rotary tool as shown in Figures 1, 2, and 6. The air is discharged in the tangential direction (arrow 14) to the rotational direction of the rotary tool 4 together with the air flow generated at a circumferential rotational speed of 4. Above the base 3 of the rotary tool 4 is a saw cover 5a integrated with the gear cover 5.
The saw cover 5a is covered with a transparent auxiliary cover 7 which is removably attached to the saw cover 5a with a mounting screw 16, and the rear side of the transparent auxiliary cover 7 (the left side in FIG. It has a bulge along the . The front side of the opposite side is made flat, and the dust introduction passage 13 is sealed by a gear cover 5, a seal plate 6 and an auxiliary cover 7 attached inside the gear cover 5.

The dust discharged in the tangential direction to the rotational direction of the rotary tool 4 is blown up along with the airflow through the sealed dust introduction passage 13 and passes through the cylindrical dust outlet 13b formed at the end of the dust introduction passage 13.
Spit out to a. The dust discharged from the dust outlet 13a is repelled with airflow into the transparent dust collecting case from the suction port 8f of the transparent dust collecting case 8 connected to the dust outlet 13a. The dust that is repelled by the air flow is
Due to the increase in the volume of the passage from the rotary tool tip to the inside of the dust collection case 8 via the dust introduction passage 13, the flow velocity is reduced, especially the dust discharge port 13.
From a to the inside of the dust collection case 8, the flow rate is rapidly reduced because it is repelled into an empty space, and the flow speed is suddenly reduced, colliding with the partition plate 8a provided inside the dust collection case 8 and stalling. However, dust that is heavier than the airflow falls downward and accumulates from the bottom of the dust accumulation chamber 8b. On the other hand, air currents lighter than dust and fine dust can be removed by the partition plate 8a inside the dust collection case 8.
The dust accumulation chamber 8b of the dust collection case 8 after colliding with
turns (arrow 19) and flows into the ventilation chamber 8c,
Here too, it collides with the partition plate 8g of the ventilation chamber 8c, weakening the flow velocity, and then the next partition plate 8g of the ventilation chamber 8c.
The flow velocity was weakened by colliding with the partition plate 8g one after another.
The fine dust that flowed in together with the air flow falls downward and accumulates every time it collides with the partition plate 8g. A small amount of fine dust that cannot completely fall flows through the recycling passage 16 to the exhaust port 17 of the dust collection case 8 along with the airflow that has become a breeze. The exhaust port 17 communicates with a residual dust discharge port 15 provided in the saw cover 5a, and a small amount of fine dust and airflow are passed through the exhaust port 1.
7 and flows to the residual dust outlet 15. The residual dust outlet 15 is located below the dust introduction passage 13.
The small amount of fine dust and air flow that flowed out of the residual dust outlet 15, which is provided above the base 3, is combined with the air flow and dust generated at the peripheral speed of rotation due to cutting of the new rotary tool 4. The dust is blown up again into the dust introduction passage 13 and repelled into the dust collection case 8.

The amount of dust accumulated inside the dust collection case 8 as described above can be visually checked from the outside of the dust collection case 8, and when it is full, the dust collection case cover hook 8d is removed and the dust collection case cover 8 is removed.
e can be opened and discharged. FIG. 7 shows a state in which the dust collection case 8 is opened.

The dust collection case 8 has a cylindrical portion 13b of an exhaust port 13a formed at the end of the dust introduction passage 13.
By inserting the suction port 8f of the dust collection case 8, which is configured to be removable, through the rubber gasket 18 fitted into the hole of the dust collection case 8, it can be attached and fixed to the main body of the portable electric circular saw. This provides communication and circulation between the dust introduction passage 13 inside the saw cover 5a and the dust collection case 8.

As described above, according to the present invention, a rotary tool is provided with a dust collection case attached to a main body of a portable power tool, the dust collection case has an inlet and a dust accumulation chamber, and the upper part than the base is sealed. In the dust collection mechanism of a portable power tool in which the suction port of the dust collection case is connected to the dust discharge port of the cover, the dust collection case is provided with an exhaust port and the exhaust port is communicated with the inside of the cover. Most of the dust that flows into the dust case is accumulated inside the dust collection case, and only fine dust flows back into the cover along with the airflow, which reduces the amount of fine dust that leaks out of the machine and improves dust collection efficiency. It is possible to provide a high dust collection mechanism.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the portable dust collector according to the present invention in Fig. 6, Fig. 2 is a partially sectional side view of Fig. 1, and Figs. 3 and 4 are the same as in Fig. 2. cc-line sectional view, dd-line sectional view, Figure 5 is the 6th
6 is a plan view of FIG. 1, and FIG. 7 is a perspective view of the dust collection case with the dust collection case opened. 3 is a base, 4 is a rotary tool, 5a is a saw cover, 8 is a dust collection case, 8a is a partition plate, 8b is a dust accumulation chamber, 8c is a ventilation chamber, 8f is an inlet, 13
a is the dust outlet, 15 is the residual dust outlet, 1
6 is the recycling passage, and 17 is the exhaust port.

Claims (1)

[Claims] 1. A portable power tool has a dust collection case attached to the main body, the dust collection case has an inlet and a dust accumulation chamber, and the upper part of the base is sealed to the dust discharge port of the cover of the rotary tool. A collection of portable power tools characterized in that a dust collection mechanism for a portable power tool is connected to an inlet of a dust case, and the dust collection case is provided with an exhaust port, and the exhaust port is communicated with the inside of the cover. Jin mechanism.