JP7353788B2 - Blower and blower housing - Google Patents

Description

The present invention relates to a blower, and more particularly to a blower having a blower body and a casing that houses the body.

A vortex blower uses a fan casing installed opposite an impeller to form an annular flow path from the suction port to the discharge port, and sucks gas from the suction port by the rotational movement of the impeller driven by a motor. , configured to apply pressure within the flow path.

In recent years, in response to increasing demands for smaller and lighter blowers, higher discharge pressures, and lower noise, various research and developments have been conducted on the structure and shape of the impellers. At the same time, the casings that house them are also required to be smaller, lighter, and soundless.

As described above, with regard to reducing the noise of a blower, for example, Patent Document 1 discloses a silencer that houses a blower therein. The muffler has a structure in which a housing covered with a sound-absorbing material is placed over a blower, and includes a muffler passage and a muffler duct that absorb noise from the blower.

JP 10-220390

There is a problem of wanting to further reduce the weight and improve the silencing effect compared to Patent Document 1. To address this issue, a known technology is called Helmholtz sound absorption, in which multiple holes are drilled in metal to absorb sound in a specific frequency range.

However, since Helmholtz sound absorption is specialized for absorbing sound at a specific frequency, even if it is applied to a muffler and absorbs the frequency at which the noise peaks, it cannot absorb sound at other frequencies. Therefore, the present inventors investigated whether it is possible to improve the sound silencing effect by using it in conjunction with conventionally used sound absorbing materials such as urethane. As a result, we were able to improve the sound deadening effect, but due to the low thermal conductivity of the urethane material, a new problem arose: the temperature inside the housing rose.

An object of the present invention is to provide a blower having a silencing device that prevents temperature rise while improving the silencing effect.

In order to solve the above-mentioned problems, for example, the invention described in the claims is applied. That is, the blower includes an electric motor, blower blades fixed to the load side of the rotating shaft of the electric motor, a fan fixed to the opposite load side of the rotating shaft, and a suction port and a discharge port located at the lower part of the fan. a blower body including an outlet, and a housing that covers all sides and an upper part of the blower, and the housing includes a storage chamber that stores the blower body, and an intake chamber that is adjacent to the fan side of the storage chamber. , a duct chamber adjacent to the intake chamber and housing a duct extending from the discharge port to the ceiling of the housing, and a sound absorption chamber and an exhaust chamber adjacent to the upper part of the storage chamber and the intake chamber.

According to one aspect of the present invention, it is possible to provide a blower that reduces temperature rise while reducing noise from the blower main body.

Other objects and effects of the present invention will become apparent from the following description.

1 is an external perspective view of a blower according to Example 1 to which the present invention is applied. 1 is a longitudinal sectional view of a blower according to Example 1 to which the present invention is applied. FIG. 2 is a partially exploded perspective view of a housing according to Example 1 to which the present invention is applied. 1 is a cross-sectional view of a blower according to Example 1 to which the present invention is applied. FIG. 2 is an enlarged sectional view of the inner wall of the housing according to Example 1 to which the present invention is applied. 1 is an exploded perspective view of a casing according to Example 1 to which the present invention is applied. FIG. FIG. 2 is a vertical cross-sectional view of a casing according to Example 1 to which the present invention is applied.

FIG. 1 is a perspective view of a blower 1 according to a first embodiment to which the present invention is applied, and FIG. 2 is a longitudinal cross-sectional view of a housing 2 viewed from the y-axis direction.

A blower 1 shown in FIG. 1 includes a housing 2 having a box-like appearance and a blower main body 3 (not shown) housed within the housing 2. The blower 1 shown in FIG. Extending toward the front in the x direction is an intake duct 301 extending from the blower main body 3, which will be described later. The housing 2 is provided with at least one ventilation port 21 (two in FIG. 1) for exchanging air between the inside and the outside. The opening of the ventilation port 21 may be left as is, or a fine mesh filter or the like may be provided to prevent dust from entering the housing 2. Hereinafter, the structures of the blower main body 3 and the housing 2 will be explained using FIGS. 2 to 4.

As shown in FIG. 2, the inside of the housing 2 is divided into a plurality of rooms by inner walls. Located in the center is the blower main body 3 and the blower storage chamber 201 in which the blower main body 3 is stored.

The blower main body 3 consists of an impeller section and an electric motor section that rotationally drives the impeller section. 102 is an impeller (not shown), 103 is a casing, and 101 is an electric motor that drives the impeller 102. One end of the pressure boosting passage in the casing is connected to the discharge port 105 via a discharge side passage, and the other end is connected to the intake port 106 via a suction side passage. The discharge side passage and the suction side passage are provided in parallel. The booster path is formed in an annular shape around the rotation center of the impeller 102, that is, the rotation axis of the electric motor 101, and has a groove shape with a semicircular arc cross section that opens in a direction parallel to the rotation axis. Although not shown in the figure, a partition wall is installed between the discharge side passage 105 and the suction side passage 106 to block the pressure increase path. Reference numeral 104 denotes a cooling fan and a fan cover fixed to the rotating shaft of the electric motor 101 on the side opposite to the impeller 102 . The electric motor 101 and the casing 103 are provided with cooling fins for cooling.

In the blower body 3, when the impeller 102 is rotationally driven by the electric motor 101, gas is sucked from the suction port 106 through the suction side passage 106 by the action of the impeller 102, and this sucked gas is heated by the impeller 102. It is compressed and conveyed to the discharge side passage. Then, the highly pressurized gas passes through the discharge side passage and is discharged from the discharge port 105. On the other hand, as the electric motor 104 rotates, the cooling fan 104 takes in air from the intake chamber 202 adjacent to the blower storage chamber 201 and blows the air along the cooling fins, thereby cooling the electric motor 101 and the vicinity of the impeller of the casing 103.

The housing 2 has a box-like appearance. Reference numeral 22 is a base portion on which the blower main body 3 is arranged, and 24 is a caster provided under the base portion 22 for movement. At the location where the blower body 3 of the base portion 22 is installed, the base portion 22 has a sound absorbing material 222 laid on a metal plate 220, and an elastic member such as rubber is provided at a position where it comes into contact with the legs of the blower body 3. (not shown). This is to prevent vibrations from being transmitted to the blower body 3 when the blower 1 is moved by the casters 24. If the blower 1 is not to be moved once it has been installed, the casters 24 may be omitted.

A storage chamber 201 in which the blower main body 3 is stored is provided in the center of the housing 2, an intake chamber 202 adjacent to the opposite load side of the storage chamber 201, and a duct chamber 203 adjacent to the opposite load side of the intake chamber 202. , a sound absorption chamber 204 and an exhaust chamber 205 are provided adjacent to the upper part of the storage chamber 201, respectively.

As shown in FIG. 3, air taken into the blower body 3 from outside the housing 2 through the intake duct 301 and the intake port 106 is compressed within the blower and is discharged to the outside of the blower body 3 through the exhaust port 105 and the exhaust duct 302. Ru. The exhaust duct 302 is connected to an exhaust chamber 205 provided above the storage chamber 201. Air within the exhaust chamber 205 is discharged to the outside of the housing from a ventilation port 21 provided in the housing 2. The sound absorption chamber 204 includes a ventilation port 21 and a connection port with the intake chamber 202, and intake air from the cooling fan 104 is sent from outside the housing 2 to the storage chamber 201 via the sound absorption chamber 204 side. In this way, the blower body 3 can be efficiently cooled by separating the rooms and ventilation openings so that the high-temperature exhaust from the blower body 3 and the intake air for cooling the blower body 3 do not mix.

FIG. 4 shows a cross-sectional view of the housing 2 viewed from the z direction. 4 is a control unit that controls the electric motor 101, and is composed of an inverter and the like. 401 is a cover for attaching the control unit. If the control section 4 is attached directly to the outer wall of the storage room 201, there is a risk of failure due to vibration or heat, so the control section is attached to the control section cover 401.

FIG. 5 shows a schematic diagram of a sound absorbing structure provided on a part of the inner wall of the housing 2. The outer wall and the like of the casing 2 are made of a metal plate 220, and the inner wall has a sound absorbing structure combining a mesh metal member 221 and a sound absorbing material 222. The mesh metal member 221 is provided with a plurality of circles having a predetermined interval and a predetermined diameter so as to reduce sound at a predetermined frequency, and has a net-like appearance. For example, it may be made of punching metal. As the sound absorbing material, it is preferable to use a porous material that allows air to pass through, such as urethane.

The frequency (resonance frequency) at which sound can be absorbed by the mesh metal plate 221 is determined by the following equation 1.

Here, c is the speed of sound, p is the aperture ratio of the mesh metal plate 221, t is the thickness of the mesh metal plate 221, and d is the diameter of the circle provided on the mesh metal plate 221. Lc is the thickness of the air layer behind, and in this embodiment, it is the distance from the mesh metal plate 221 to the metal plate 220 on the outer wall of the casing. For example, in the case of the mesh metal plate 221 provided between the storage chamber 201 and the intake chamber 202, Lc is the length of the intake chamber 202 in the x direction.

The noise generated from the blower main body 3 includes sounds of various wavelengths from loud sounds to soft sounds, and therefore has multiple frequency peaks. Therefore, by designing the housing 2 by adjusting p, t, d, and Lc in (Formula 1), a structure that can absorb sound in a desired frequency band can be obtained. In this way, most of the noise generated from the blower body 3 can be removed.

FIG. 6 shows an exploded perspective view of the sound absorbing structure of the housing 2, and FIG. 7 shows a cross-sectional view. Since the source of the noise is the blower main body 3, a mesh metal plate 221 is provided as an inner wall surrounding the blower main body 3. Specifically, they are the inner wall between the intake chamber 202 and the storage chamber 201 and the inner wall between the storage chamber 201 and the sound absorption chamber 204. In order to further enhance the sound absorption effect, an inner wall 210a may be provided on the load side of the blower main body 3 in the storage chamber 201, as shown in FIG. In that case, the inner wall 210 is composed of a mesh metal plate 221 and a sound absorbing material 222. Alternatively, the inner wall between the duct chamber 203 and the intake chamber 202 may also be formed of the mesh metal plate 221.

Next, a sound absorbing material 222 is provided between the mesh metal plate 221 and the noise source. In the case of this embodiment, the sound absorbing material 22 is attached to the surface of the mesh metal plate 221 facing the storage chamber. By providing the inner wall of the casing 2 with a structure that exhibits a sound absorption effect in this manner, the sound absorption performance of the casing 2 can be improved. In order to further enhance the sound absorption effect, all areas other than the surface of the mesh metal plate 221 may be covered with a sound absorption material 222 as shown in the figure. This makes it possible to absorb large noise frequencies with the mesh metal plate 221 and absorb other frequencies with the sound absorbing material 222.

As explained above, in the blower 1 described in this embodiment, by extending the exhaust duct to the upper part of the storage chamber, the blower exhaust air does not enter the intake of the cooling fan, and the blower body can be efficiently cooled. Become. Therefore, even with an inner wall structure that combines Helmholtz sound absorption and sound absorption material, the temperature of the blower body 3 does not rise too much, and it is possible to drive the blower body 3 safely at a low temperature.

Note that the present invention is not limited to the structure described in this embodiment, and can be applied to various types of blowers.

1: Blower 101: Electric motor 102: Blower impeller 103: Casing 104: Cooling fan 106: Intake port 105: Exhaust port 2: Housing 21: Ventilation port 22: Base portion 24: Caster 201: Storage chamber 202: Intake chamber 203 : Duct chamber 204: Sound absorption chamber 210a; Partition wall 210b: Partition wall 220: Metal plate 221: Net-like metal plate 222: Sound absorption material 3: Blower body 301: Intake duct 302: Exhaust duct 4: Control section 401: Control section cover.

Claims (6)

electric motor and
a blower blade fixed to the load side of the rotating shaft of the electric motor;
a fan fixed to the opposite load side of the rotating shaft;
a blower body including a suction port and a discharge port located at the bottom of the fan;
A casing that covers the four sides and the top of the blower main body ,
The housing includes a storage chamber that stores the blower main body;
an intake chamber adjacent to the fan side of the storage chamber through which cooling air passes;
a duct chamber adjacent to the intake chamber and extending from the discharge port to above the storage chamber and housing an exhaust duct through which exhaust air from the blower body passes;
a sound absorption chamber communicating with the intake chamber on one side and a first ventilation port on the other side;
an exhaust chamber connected to the exhaust duct on one side and equipped with a second ventilation port on the other side,
Only the exhaust gas passes through the exhaust chamber and is exhausted from the second ventilation port,
In the blower, the sound absorption chamber and the exhaust chamber are arranged adjacent to upper portions of the storage chamber and the intake chamber. The blower according to claim 1,
In the blower, among the inner walls of the housing, an inner wall between the storage chamber and the intake chamber and an inner wall between the storage chamber and the sound absorption chamber are provided with a mesh metal plate. The blower according to claim 2,
In the blower, a sound absorbing material is provided on a surface of the mesh metal plate inside the housing that faces the storage chamber. A housing for a blower,
a storage chamber that stores the blower body ;
an intake chamber adjacent to the fan side of the storage chamber through which cooling air passes;
a duct chamber that is adjacent to the intake chamber and extends from the discharge port to above the storage chamber and stores an exhaust duct through which exhaust air from the blower body passes;
a sound absorption chamber communicating with the intake chamber on one side and a first ventilation port on the other side;
an exhaust chamber connected to the exhaust duct on one side and equipped with a second ventilation port on the other side,
Only the exhaust gas passes through the exhaust chamber and is exhausted from the second ventilation port,
In the blower housing, the sound absorption chamber and the exhaust chamber are arranged adjacent to upper portions of the storage chamber and the intake chamber. The blower housing according to claim 4,
A case for a blower, wherein, among the inner walls, an inner wall between the storage chamber and the intake chamber and an inner wall between the storage chamber and the sound absorption chamber are provided with a mesh metal plate. The blower housing according to claim 5,
A housing for a blower, wherein a sound absorbing material is provided on a surface of the mesh metal plate facing the storage chamber.

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