JP2017067356A - Ventilation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ventilation device that can obtain sufficient silence effect and has high air blow efficiency and small-sized ventilation device constitution.SOLUTION: There is provided a ventilation device 1 consisting of an air intake 4 for sucking air in a living room, two active mute air ducts 6 as cylindrical bodies connected to an exhaust port 5 for discharging air and the air intake 4 so that the air flows inside, an air blow part 7 connected to the exhaust port 5 to discharge the air, and an air blow space 8 where the air flows from the active mute air ducts 6 to the air blow part 7, the active mute air ducts 6 being the two cylindrical bodies arranged in parallel with a part of a fan casing 10 interposed.SELECTED DRAWING: Figure 1

Description

The present invention relates to a ventilator to be installed on a ceiling or a wall surface or the like of the room, and more particularly to a ventilation apparatus having an active silencer for silencing the noise of the blower occur during operation.

  In recent years, ventilation fans installed in living rooms are required to reduce noise generated during operation. As one means for solving such a problem, there is a method of mounting an active silencer on a ventilation fan.

  Conventionally, as an active silencer for a duct, as shown in the schematic diagram of FIG. 7, an internal original sound reference microphone 102 and a silencer speaker 103 are sequentially provided in the duct 101 with appropriate intervals from the upstream side. And an error microphone 104 and an arithmetic controller 105 respectively connected to the error microphone 104 are known (see, for example, Patent Document 1).

  In this type of apparatus, the frequency of the generated sound propagating in the duct 101 together with the air flow 106 is detected by the reference microphone 102, and a signal having a phase opposite to that of the generated sound is generated by the arithmetic controller 105. This opposite phase signal is emitted from the muffler speaker 103 into the duct 101 to cancel and mute the generated sound. The error microphone 104 monitors the internal sound, and the signal sent from the arithmetic controller 105 to the mute speaker 103 is adjusted so that the output of the error microphone 104 becomes zero.

  Such an active silencer silences the noise propagating in the one-dimensional sound field, and the noise propagating through the air passage can be controlled up to a frequency band that becomes a plane wave.

  However, the frequency that becomes a plane wave changes depending on the diameter of the duct, and when the duct diameter is large, the frequency that becomes a plane wave narrows to the low frequency side. Therefore, when the duct diameter is large, it cannot be assumed that the sound field is a one-dimensional sound field, and high-frequency noise that must be silenced cannot be silenced.

  For this reason, what is known as an active silencer for a large-diameter ventilation path is a combination of a small-diameter duct (small-diameter duct) obtained by dividing the silencer ventilation path into cells (for example, Patent Document 2). reference). By using each small-diameter duct, the frequency range of noise propagating by plane waves is broadened to the high frequency side and controlled.

  The active silencer will be described below with reference to FIG.

  As shown in FIG. 8, the large-diameter duct is divided into small-diameter ducts 201, 202, 203, and 204, and a muffler speaker 103 is installed in each small-diameter duct. The small-diameter duct 201 is provided with a reference microphone 102 on the upstream side and an error microphone 104 on the downstream side with respect to the installation position of the muffler speaker 103.

  Noise signals detected by the reference microphone 102 and the error microphone 104 are input to the arithmetic controller 105. The arithmetic controller 105 generates a drive signal to be output to the mute speaker 103 based on the input noise signal. The muffler speaker 103 installed in each small-diameter duct outputs this drive signal, that is, silences the noise propagating through each small-diameter duct with the same canceling sound.

  Thus, by dividing the large-diameter duct into a cell shape and combining it with a small-diameter duct, the frequency band propagated by plane waves becomes wider on the high-frequency side, and a sufficient silencing effect can be obtained.

  In FIG. 7, the same or similar components as those shown in FIG. 8 are indicated by the same reference numerals.

Japanese Utility Model Publication No. 5-11198 JP-A-9-160567

  In general, a ventilation device as a ventilation fan includes a fan on the reference microphone 102 side of Patent Document 2 and an opening connected to the living room space on the error microphone 104 side. Therefore, in order to reduce the noise of the fan released into the living room space, it is necessary to provide an active silencer between the fan and the opening.

  However, since the dimension of the active silencing air path is required for active silencing in addition to the size of the fan, the dimension of the active silencing air path in one direction is extremely large and elongated, and the installation environment is limited. It will be. Further, if the fan and the active silencer are simply arranged in parallel in the direction of the active silencer air path, a bent air path configuration results in a high pressure loss air path, and the air blowing efficiency is reduced. Therefore, there is a problem of obtaining a silencing effect without reducing the dimension in the direction of the active silencing air path and reducing the blowing efficiency.

  Accordingly, an object of the present invention is to provide a ventilator that can provide a sufficient silencing effect, has a high ventilation efficiency, and has a small product size in the direction of the active silencing air passage even if the ventilator is provided with an active silencer. .

  Therefore, the ventilator according to the present invention includes an outer shell of the box, a suction port for sucking two air provided on one surface of the outer shell, and an air provided on a side surface of the suction port of the outer shell, or on an opposing surface. A discharge port that discharges air, two active silencing air paths of a cylindrical body that is connected to the suction port and through which air flows, a blower that is connected to the discharge port and exhausts air, and the active silencing air A ventilation device including a fan space through which air flows from a road toward the air blowing unit, the air blowing unit including the centrifugal fan and guiding the air to the discharge port; The road is formed by arranging two cylindrical bodies in parallel with a part of the fan casing interposed therebetween, thereby achieving the intended purpose.

  ADVANTAGE OF THE INVENTION According to this invention, even if it equips a ventilator with an active silencer, it can be set as a ventilator with a sufficient silencing effect, high ventilation efficiency, and a small dimension of an active silencing air path direction.

Sectional drawing of the ventilator which concerns on Embodiment 1 of this invention Sectional perspective view of the ventilating apparatus according to Embodiment 1 of the present invention. A side view of a ventilation device in which the active silencer air passage 6 is one air passage. Sectional perspective view of Modification 1 of Embodiment 1 of the present invention Sectional perspective view of Modification 2 of Embodiment 1 of the present invention Sectional perspective view of Modification 3 of Embodiment 1 of the present invention Overview of conventional active silencer A perspective view of a conventional active silencer

  A ventilator according to an embodiment of the present invention is a ventilator that sucks indoor air and exhausts it to the outside, and the ventilator is provided on the outer surface of the box and on one surface of the outer shell. Two suction ports, one suction port for sucking air, a discharge port for discharging air provided on the side surface or the opposite surface of the outer shell, and a tubular body connected to the suction port and through which air flows An active silencer air passage, a blower connected to the discharge port and exhausting air, and a blower space through which air flows from the active silencer air passage toward the blower, the blower unit including the centrifugal fan The ventilating apparatus includes a fan casing that encloses and guides air to the discharge port, and the active silencing air path is configured by arranging two cylindrical bodies in parallel with a part of the fan casing interposed therebetween.

  As a result, the active silencer air passage and the air blowing portion overlap in the vertical direction of the suction port, and the distance in the vertical direction of the suction port can be reduced. Further, by dispersing the air passages on both sides of the air blowing portion, the flow from the cylindrical body to the air blowing portion can be dispersed, the air passage can be widened, and the internal pressure loss can be reduced. Further, by reducing the width of the cylindrical body by dividing the active silencing air path into two, the maximum frequency f of the active silencing target f determined by the width L of the cylindrical body f (= 0.. 5 × sound speed ÷ L) can be increased, and the silencing effect can be increased.

(Embodiment 1)
Hereinafter, the ventilation apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 and 2. 1 is a cross-sectional view of the ventilator, and FIG. 2 is a cross-sectional perspective view of the ventilator (upper surface side view of FIG. 1).
The ventilation device 1 according to the first embodiment is a box having an outer shell 3 that protrudes from the ceiling 2 to the back of the ceiling, and is open on the side surface of the outer wall 3 of the outer shell 3 that is located substantially flush with the surface of the ceiling 2. The two suction ports 4, the discharge port 5 opened on the surface facing the suction port 4, the active silencing air passage 6 of the cylindrical body connected to the suction port 4, and the blower unit 7 connected to the discharge port 5 The active sound deadening air path 6 and the air blowing space 8 between the air blowing portions 7 are formed.

  The blower unit 7 includes a fan casing 10 that encloses a centrifugal fan 9, and the fan casing 10 includes fan suction ports 11 on both surfaces of the centrifugal fan 9 in the axial direction.

  The active silencing air path 6 includes a detection microphone 12 so that the sound inside the cylindrical body can be detected, and a silencing speaker 13 so that the sound can be emitted inside the cylindrical state.

  Here, the fan casing 10 is rotated by the centrifugal fan so that the active silencing air passage 6 and the air blowing section 7 overlap between the suction port 4 and the exhaust port 5 in the vertical direction of the ceiling 2 which is the active silencing air passage direction. Two active silencing air paths 6 are arranged in parallel so as to be sandwiched from each other in the radial direction of the shaft 15.

  The above is the configuration of the ventilation device 1 according to the present embodiment.

  Next, the operation and action of each part during operation of the ventilation device 1 will be described.

  In the above configuration, when the centrifugal fan 9 driven by the motor (not shown) of the ventilation device 1 rotates, the indoor air is sucked from the suction port 4 and passes through the active silencing air passage 6, the air blowing space 8, and the air blowing unit 7. Thus, an air flow reaching the discharge port 5 is generated, and the air is exhausted from the exhaust duct 14 connected to the discharge port 5 to the outside. At the same time, the noise of the centrifugal fan 9 is radiated as radiated sound from the air blowing space 8, the active silencing air passage 6, and the suction 4.

  In general, a duct-like air passage has a function of making the sound pressure into a plane wave that is uniform in the cross-sectional direction, so that the sound pressure propagates one-dimensionally within the active silencing air passage 6 that is a duct-like air passage. To do. Therefore, in the active silencing air path 6, the detection microphone 12 detects sound and transmits the detected noise as a noise signal to an arithmetic controller (not shown). The arithmetic control unit generates a canceling sound (anti-phase sound) from the muffler speaker 13 based on the sound detected by the detection microphone 12 so that the radiated sound is minimized, and mutes the sound in the active silencing air path 6. The calculation control signal is faster than the sound speed, but a desired time is required for the calculation. Therefore, it is necessary to secure a certain distance between the detection microphone 12 and the mute speaker 13 to increase the sound transmission time. become. Therefore, the length of the active silencing air passage is set according to the processing time.

  Here, between the suction port 4 and the discharge port 5, the active silencing air passage 6 and the air blowing unit 7 are provided so as to overlap in the vertical direction of the ceiling 2, thereby reducing the vertical dimension. That is, it is possible to provide a ventilator with a small product size in the direction of the active silencing air path.

  In addition, since the two active silencing air passages 6 are arranged in parallel with the fan casing 10 in between, the desired exhaust amount can be seen from two directions like the air flow indicated by the arrows in the air blowing space 8. Leads to the blower.

  FIG. 3 shows a ventilation device 50 in which the active silencing air passage 6 is one air passage that does not sandwich the fan casing. When this case is compared with the present invention, the ventilation device 50 reduces the vertical dimension of the ceiling 2 as in the present invention. However, when the same flow rate is exhausted with the same size as that of the ventilator 1, the airflow space 58 has a smaller air passage cross-sectional area than the airflow space 8, and the pressure loss at the time of airflow increases, resulting in a decrease in airflow efficiency.

Further, since the active silencing air passage 6 is divided into two, the active silencing air passage which does not implement the present invention is used in the case where the air passage cross-sectional area of the entire active silencing air passage is kept constant in order to make the pressure loss constant. Compared to 56, the width of the active silencing air passage is reduced. Therefore, by performing a silencing process in each of the two active silencing air paths 6 having a small air path width, the active silencing target maximum frequency f (= 0.5 × sound speed ÷ determined by the width L of the active silencing air path. L) can be increased, and the silencing effect can be increased.
(Modification 1)
In the first embodiment, the two active silencing air passages 6 are arranged in parallel so as to sandwich the fan casing 10 from the radial direction of the centrifugal fan rotating shaft 15. However, as shown in the cross-sectional perspective view of the ventilation device 40 in FIG. 4, the two active silencing air passages 6 may be arranged in parallel so that the centrifugal fan rotating shaft 15 is sandwiched from the axial direction. It is desirable that the centrifugal fan 9 has a double-suction configuration having two fan inlets 11 so that air is sucked in from the two active silencing air paths 6 in a balanced manner to increase the blowing efficiency.
(Modification 2)
In the first embodiment, the ventilation device is configured by two active silencing air paths. However, as shown in the cross-sectional perspective view of the ventilation device 20 in FIG. 5, the number of active silencing air paths is not limited to two, for example, two active silencing A air paths 21 sandwiching the fan casing 10, and similarly fan casings Two active silencing B air paths 22 sandwiching 10 are provided, and a pair of active silencing A air path 21 and active silencing B air path 22 is created on each side of the fan casing 10 by four active silencing air paths. It may be configured.
(Modification 3)
In the first embodiment, the discharge port 5 is provided on the opposite surface of the suction port 4. However, as shown in the schematic perspective view of the ventilation device 30 of FIG.

  The ventilator according to the present invention is useful as a ventilator such as a house ventilation fan or a range hood with suppressed noise.

DESCRIPTION OF SYMBOLS 1 Ventilator 2 Ceiling 3 Outer 4 Suction inlet 5 Outlet 6 Active silencer air path 7 Blower part 8 Blower space 9 Centrifugal fan 10 Fan casing 11 Fan inlet 12 Detection microphone 13 Silent speaker 14 Exhaust duct 15 Centrifugal fan rotating shaft 20 Ventilation Device 21 Active silencer A air path 22 Active silencer B air path 30 Ventilator 40 Ventilator 50 Ventilator 56 Active silencer air path 58 Ventilation space

Claims (1)

An outer shell of the box, a suction port for sucking two air provided on one surface of the outer shell, a discharge port for discharging air provided on a side surface of the suction port of the outer shell or on the opposite surface, and the suction Two active silencing air passages connected to the mouth through which air flows, an air blowing portion connected to the exhaust port for discharging air, and air from the active silencing air passage toward the air blowing portion The ventilation section includes a fan casing that encloses the centrifugal fan and guides air to the discharge port, and the active silencing airflow path is a part of the fan casing. A ventilation device with two cylindrical bodies arranged in parallel.

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