JPH07186103A - Electromotive plane - Google Patents

Abstract

PURPOSE:To facilitate maintenace by a simple structure and to achieve the lowering of noise, in an electromotive plane wherein a part of a plane blade chamber forms a cut powder cut-off wall separating a cut powder discharge passage from the plane blade chamber, by providing a through-hole to the cut powder cut-off wall. CONSTITUTION:In a cut powder cut-off wall 12, air compressed in front of the rotary direction of a plane blade 4 accompanied by the rotation of a plane blade body 5 is released to a cut powder discharge passage 11 by the through- holes 13 arranged on the straight line parallel to a rotary shaft. Therefore, the sudden change of pressure at a time when the plane blade 4 passes the end part of the cut powder cut-off wall 12 is relaxed and noise is reduced. As a result of measuring a noise level while the positions of the through-holes 13 are changed, when the positions of the through-holes 13 in the cut powder cut-off wall 12 are set to the positions of 14-30 deg. from the center of the plane blade body 5, noise becomes lowest and, when the through-holes 13 are made circular and the angle of the through-holes 13 is set to 15 deg. with respect to the plane blade cylinder 5, the diameter of the through-holes 13 is set to about 0.5-0.75 of the pitch of the through-holes 13 to most reduce noise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to noise reduction of an electric plane.

[0002]

2. Description of the Related Art A conventional electric plane is provided with a plane blade chamber for accommodating a rotary plane blade cylinder having a plane blade attached thereto, and the plane blade chamber is composed of the front base, rear base and a part of the main body. Has been done. The respective ends of the front base and the rear base forming the working opening and the end of the chip blocking wall limiting the chip discharging opening extend in parallel with the blade edge of the plane blade. During the operation of the electric plane, the plane blade protruding in the radial direction from the plane blade cylinder rotates at a high speed with a small space from the plane wall of the plane blade, and cuts the work material as the plane blade cylinder rotates.

[0003]

In the above-mentioned conventional electric plane, when the plane blade passes through the front base, the rear base, and the end of the chip blocking wall extending parallel to the cutting edge, the plane blade barrel And the pressure of the space formed by the plane wall of the plane blade suddenly changes and noise is generated. Of these three locations, the noise is particularly loud at the end of the chip blocking wall. As a result of measuring the pressure and sound pressure waveform at the end of the chip blocking wall, as shown in FIG. The pressure at the end of the chip blocking wall fluctuates greatly, and the sound pressure waveform also fluctuates greatly. Generally, in order to reduce this noise, methods such as reducing the radius of the plane blade cylinder, lowering the number of rotations of the plane blade cylinder, widening the distance between the plane blade cylinder and the plane blade chamber wall have been considered, All of them reduce the work ability of planes, and there is a problem that they are unrealistic.

Then, in Japanese Patent Publication No. 63-56841,
There is disclosed an example in which the end portion of the chip blocking wall is configured obliquely with respect to an imaginary straight line parallel to the axis of the plane blade cylinder to reduce noise.
However, in order to obtain the sound deadening effect, it is necessary to make a large angle at the end of the chip blocking wall, and it is difficult to obtain a sufficient effect in a narrow space inside the plane body.

Further, in Japanese Utility Model Publication No. 51-62194,
An example in which a hole is provided at the base end of the work opening of the plane is disclosed, but in the electric plane to which the present invention is applied, the sound generated from the end of the chip blocking wall is large, so the base There is a problem that the noise reduction effect cannot be expected even if a hole is provided in the. An object of the present invention is to eliminate the above-mentioned conventional drawbacks and provide a low noise electric plane having a simple structure and easy maintenance.

[0006]

The above object is achieved by limiting the opening area of the chip discharging opening and providing a through hole in the chip blocking wall which simultaneously forms the plane blade chamber and the chip discharging passage. .

[0007]

In the electric plane constructed as described above, the air compressed forward in the rotation direction of the plane blade along with the rotation of the plane blade cylinder passes through the through hole provided in the cutting wall to pass the chip discharge passage. It passes and is released into the open air. Therefore, when the plane blade passes the end of the chip blocking wall, the pressure that collides with the end of the chip blocking wall is reduced. As a result, pressure fluctuations at the ends of the chip blocking wall, where noise is generated, are reduced, and noise is reduced. Moreover, in terms of structure, since the structure is simple, the increase in production cost is minimal.

By providing a hole in the plane blade chamber wall other than the chip blocking wall, the plane blade chamber and the main body housing inner chamber, which is the main body housing inner wall, communicate with each other. However, since the inner chamber of the main body housing does not communicate with the outside air, the air compressed by the rotation of the plane blade cylinder is not released. Therefore, the pressure fluctuation is not reduced, and even if holes are provided in the plane blade chamber wall other than the chip blocking wall, there is no noise reduction effect.

[0009]

1 is a partial cross-sectional side view of an electric plane showing an embodiment of the present invention, FIG. 2 is an enlarged view of an essential part of FIG. 1, and FIG. 3 omits a front base, a rear base, and a plane blade barrel. FIG. 4 is a perspective view of the plane blade chamber, FIG. 4 is a sectional view and a graph for explaining the relationship between the position of the through hole in the electric plane and the noise level, and FIG. 5 is the relationship between the diameter of the through hole in the electric plane and the noise level. And FIG. 7 is a perspective view showing another embodiment of the electric plane of the present invention. Here, the mechanism for transmitting the rotational force of the electric motor to the plane blade cylinder is omitted. The electric plane has a front base 1 equipped with a cutting depth adjustment mechanism.
And a rear base 2 that slides on the cutting surface, a main body 15 on which an electric motor is mounted, and a rotary plane blade cylinder 5.

The plane blade body 5 is provided with two plane blades 4 symmetrically with respect to the rotary shaft 8 of the plane blade body 5. The plane blade 4 is provided between the front base 1 and the rear base 2. It is exposed from the working opening 3 located. Of the chip discharge opening 10 which is separated from the outer peripheral surface of the plane blade cylinder 5 by a plane blade chamber wall 16 at a slight distance in the radial direction, and which is communicated with the work opening 3 and the chip discharge passage 11. The plane blade barrel 5 is rotatably supported in a plane blade chamber 6 having a substantially cylindrical shape having two openings.

A chip blocking wall 1 which is a part of the plane blade chamber wall 16 and simultaneously forms the chip discharge passage 11 and the plane blade chamber 6.
2, the chip blocking wall 12 has an opening 1 for discharging chips.
0 is restricted. Since a plurality of through holes 13 are arranged on the straight line 14 parallel to the rotary shaft 8 of the plane blade cylinder 5 in the chip blocking wall 12, the plane blade chamber 6 and the chip discharge passage 11 have through holes. 1
It is connected by 3.

In the electric plane having the above-mentioned construction, the plane blade 4 is rotated by the plane of the plane blade body 5 by the through hole 13 arranged on the straight line 14 parallel to the rotary shaft 8 in the chip blocking wall 12.
Compressed in the forward direction of rotation of the
Is released to. Therefore, the sudden change in pressure when the plane blade 4 passes the end of the chip blocking wall 12 is alleviated, and the noise is reduced.

Although the position of the through hole 13 in the chip blocking wall 12 can be set to an arbitrary position, the through hole 13 is changed as shown in FIG. When 13 is arranged at a position of 14 to 30 ° from the center of the plane blade cylinder 5, the noise is lowest, and the shape of the through hole 13 may be arbitrarily determined. When the experiment is performed by setting the angle of the through holes 13 to 5 with respect to 5, the diameter of the through holes 13 is the lowest noise when the diameter of the through holes 13 is about 0.5 to 0.75 of the pitch of the through holes 13, as shown in FIG. .

FIG. 7 shows another embodiment of the present invention. In addition to the through hole 13 provided in the chip blocking wall 12, a plurality of through holes 7 are opened in a portion of the rear base 2 which plays a part of the plane blade chamber 6, and are parallel to the rotary shaft 8 of the plane blade cylinder 5. It is arranged on the straight line 9.

As described above, in the conventional electric plane, the noise generated at the end of the chip blocking wall 12 is large, and therefore the noise reduction effect is small even if the rear base 2 is provided with a hole. However, since the noise is reduced by the through hole 13 provided in the chip blocking wall 12, the noise reducing effect can be obtained by the through hole 7 provided in the rear base 2.

[0016]

According to the present invention, the through hole is provided in the wall of the chip blocking chamber so that the chip discharge passage communicates with the plane blade chamber. Therefore, the air compressed forward in the rotation direction of the saw blade is The chips pass through the chip discharge passage and are discharged into the atmosphere, so that the noise accompanying the rotation of the plane blade cylinder can be reduced without impairing the workability.

[Brief description of drawings]

FIG. 1 is a partial sectional side view showing an embodiment of an electric plane of the present invention.

FIG. 2 is a partially enlarged cross-sectional view showing a main part of FIG.

FIG. 3 is a perspective view of a front blade and a rear base of an electric plane which is an embodiment of the present invention, and a plane blade chamber in which a plane blade barrel is omitted.

FIG. 4 is an explanatory cross-sectional view showing the hole position of the chip blocking wall and a graph showing the relationship between the position of the through hole and the noise level.

FIG. 5 is an explanatory cross-sectional view showing a hole position of a chip blocking wall and a graph showing a relationship between a size of a diameter of a through hole and a noise level.

FIG. 6 is a graph showing a pressure waveform and a sound pressure waveform at the end of the chip blocking wall in the conventional electric plane.

FIG. 7 is a perspective view of an electric plane showing another embodiment of the present invention.

[Explanation of symbols]

1 is a front base, 2 is a rear base, 3 is a work opening, 4 is a plane blade, 5 is a plane blade barrel, 6 is a plane blade chamber, 7 is a through hole,
8 is a rotary shaft, 9 is a straight line, 10 is a chip discharge opening, 11 is a chip discharge passage, 12 is a chip blocking wall, 13 is a through hole, 14
Is a straight line, 15 is a main body, and 16 is a plane blade chamber wall.

Claims (1)

[Claims] 1. A rotary type plane blade cylinder driven by an electric motor or the like, to which a plane blade is attached, and a small distance from the flow line of the blade of the plane blade except for the working opening and the chip discharging opening. An electric plane having a plane blade chamber surrounded by plane plane blade chamber walls arranged as a part, and a part of the plane blade chamber wall forming a chip blocking wall separating the plane blade chamber from the chip discharge passage. The electric plane in which the through hole is provided in the chip blocking wall.