Sounding devices and rotating equipment

Abstract

To provide a sound-making device that produces a good sound in accordance with the rotation of a rotating body of a rotating machine, and a rotating machine equipped with the same. [Solution] The sound-blowing device is a sound-blowing device installed on the rotating body of a rotating machine, and comprises a cylindrical air intake having an air intake port into which airflow flows when the rotating body rotates, a sound-blowing unit body located on the opposite side of the air intake port and which makes a sound when airflow that has passed through the air intake flows in, and an airflow adjustment mechanism provided on the sound-blowing unit body or the air intake.

Description

Technical Field

[0001] The present invention relates to a blowing device and a rotating device.

Background Art

[0002] Conventionally, there is known a monitoring device that generates an acoustic map showing the relationship between the positions of a plurality of sound sources included in a monitoring target area and the sound pressure of each sound source, and diagnoses an abnormality of a rotating machine based on the sound pressure level of the sound generated by the rotating machine (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, conventionally, there has been no proposal regarding providing a blowing device that emits sound to a rotating device to be monitored in order to monitor the operating state of the rotating device.

[0005] The problem to be solved by the present invention is to provide a blowing device that emits sound well in accordance with the rotation of a rotating body of a rotating device and a rotating device provided with the same.

Means for Solving the Problems

[0006] [[ID=,46]][1] The blowing device according to one aspect of the present invention is a blowing device provided on a rotating body of a rotating device, a cylindrical air intake having an air inlet into which an air flow flows when the rotating body rotates, a blowing portion main body that is located on the opposite side of the air inlet of the air intake and blows by the inflow of the air flow that has passed through the air intake, an air volume adjustment mechanism provided on the blowing portion main body or the air intake. It is equipped with.

[0007] [2] A sounding device according to one aspect of the present invention is, in the above [1], The airflow adjustment mechanism is provided inside the air intake and has a valve that is rotatable by the airflow flowing into the air intake.

[0008] [3] A sounding device according to one aspect of the present invention is, in the above [2], The valve is a plate-shaped member, and has a bent portion at its tip.

[0009] [4] A sounding device according to one aspect of the present invention is, in the above [2], The airflow adjustment mechanism has an air receiver located on the outer surface of the air intake, positioned on the rotation axis of the valve.

[0010] [5] A sounding device according to one aspect of the present invention is, in the above [1], The aforementioned airflow control mechanism is An opening formed on the bottom surface of the aforementioned air intake, A valve plate provided on the inner bottom surface of the air intake, the end opposite to the intake port is pivotally supported, and the valve plate is displaceable between a closed position that shields the opening and an open position that does not shield the opening. A weight provided at the end of the valve plate on the intake port side of the upper surface, A spring, with one end fixed to the weight and the other end fixed to the upper inner surface of the air intake, It has.

[0011] [6] A sounding device according to one aspect of the present invention is, in the above [1], The aforementioned air intake is roughly shaped like a truncated square pyramid.

[0012] [7] A sounding device according to one aspect of the present invention is a rotating device that includes any of the sounding devices described in [1] to [6] above. [Effects of the Invention]

[0013] According to one aspect of the present invention, it is possible to provide a whistling device that emits sound well in accordance with the rotation of a rotating body of a rotating device, and a rotating device including the same.

Brief Description of the Drawings

[0014] [Figure 1] It is a diagram showing a schematic configuration of an operation monitoring system according to the present embodiment. [Figure 2] It is a diagram showing a schematic configuration of a whistling device according to the present embodiment. [Figure 3] It is a diagram showing a schematic configuration of a whistling device according to the present embodiment. [Figure 4] It is a diagram showing a configuration of a whistling device according to the first embodiment, and shows a state during low-speed rotation of the rotating body. [Figure 5] It is a diagram showing a configuration of a whistling device according to the first embodiment, and shows a state during high-speed rotation of the rotating body. [Figure 6] It is a diagram showing a configuration of a whistling device according to the second embodiment, and shows a state during low-speed rotation of the rotating body. [Figure 7] It is a diagram showing a configuration of a whistling device according to the second embodiment, and shows a state during high-speed rotation of the rotating body. [Figure 8] It is a diagram showing a configuration of a whistling device according to the third embodiment, and shows a state during low-speed rotation of the rotating body. [Figure 9] It is a diagram showing a configuration of a whistling device according to the third embodiment, and shows a state during high-speed rotation of the rotating body. [Figure 10] It is a diagram showing a configuration of a whistling device according to a modification of the first embodiment, and shows a state during low-speed rotation of the rotating body. [Figure 11] It is a diagram showing a configuration of a whistling device according to a modification of the first embodiment, and shows a state during high-speed rotation of the rotating body. [Figure 12] It is a diagram showing a configuration of a whistling device according to a modification of the second embodiment, and shows a state during low-speed rotation of the rotating body. [Figure 13]This figure shows the configuration of a sound-blowing device according to a modified example of the second embodiment, and depicts the state when the rotating body is rotating at high speed. [Figure 14] This figure shows the configuration of a blowing device according to a modified example of the third embodiment, and is a diagram showing the state when the rotating body is rotating at a low speed. [Figure 15] This figure shows the configuration of a blowing device according to a modified example of the third embodiment, and depicts the state when the rotating body is rotating at high speed. [Modes for carrying out the invention]

[0015] The following descriptions of each embodiment will be made with reference to the drawings. However, unnecessarily detailed explanations may be omitted. For example, detailed explanations of already well-known matters and redundant explanations of substantially identical configurations may be omitted. This is to avoid the following explanation becoming unnecessarily verbose and to facilitate understanding for those skilled in the art.

[0016] (Configuration of the operation monitoring system) Figure 1 is a diagram showing the schematic configuration of the operation monitoring system 1 according to this embodiment. As shown in Figure 1, the operation monitoring system 1 according to this embodiment comprises a plurality of devices (devices 2a to 2d), sound-blowing devices 3a to 3d provided on the plurality of devices (devices 2a to 2d), a microphone 4 for collecting sounds generated from the sound-blowing devices 3a to 3d in response to the operation of the plurality of devices (devices 2a to 2d), and an operation monitoring device 10 that monitors the operating status of the plurality of devices (devices 2a to 2d) by analyzing the sounds collected via the microphone 4.

[0017] The multiple pieces of equipment (pieces 2a to 2d) are, for example, rotating equipment such as pumps installed within the pump facility.

[0018] The sound-generating devices 3a to 3d are installed in or near the drive units (not shown) of multiple devices (devices 2a to 2d). The sound emitted by the sound-generating devices 3a to 3d, which generate sound in response to the drive of the drive unit, is assigned a different frequency to each device. This allows the operation monitoring device 10 to reliably determine the operating status of each device. Details of the configuration of the sound-generating devices 3a to 3d will be described later.

[0019] Microphone 4 collects sounds generated in response to the operation of multiple devices (devices 2a to 2d) by sound-generating devices 3a to 3d installed on multiple devices (devices 2a to 2d). Microphone 4 is connected to the operation monitoring device 10, and the audio signals collected by microphone 4 are input to the operation monitoring device 10.

[0020] The operation monitoring device 10 collects sounds generated from the sound-making devices 3a to 3d installed on multiple devices (devices 2a to 2d) via the microphone 4 and analyzes the sounds (collected sound data). For example, the operation monitoring device 10 performs a Fast Fourier Transform (FFT) on the collected sounds. Alternatively, instead of performing a Fast Fourier Transform, a bandpass filter (four bandpass filters with center frequencies f1 to f4) corresponding to the frequencies of the sounds emitted by the sound-making devices 3a to 3d (for example, frequencies f1 to f4) may be applied to the collected sounds.

[0021] The operation monitoring device 10 then determines the operating status of multiple devices (devices 2a to 2d) based on the analysis results. For example, in the sound collection data that has undergone a Fast Fourier Transform, if the sound pressure level at the frequency corresponding to the monitored device exceeds a threshold, the operating status of the device is determined to be "operating," and if it falls below the threshold, the operating status of the device is determined to be "stopped."

[0022] Furthermore, if the operation monitoring device 10 applies a bandpass filter to the sound collection data instead of the fast Fourier transform, it will determine that the operating status of the monitored equipment is "operating" if the sound pressure level at the frequency corresponding to the equipment exceeds a threshold in the sound collection data after applying the bandpass filter, and will determine that the operating status of the equipment is "stopped" if it falls below the threshold.

[0023] The results determined by the operation monitoring device 10 (operating status of equipment 2a to 2d) are output to a display unit (not shown) and recorded in the database of the storage unit as the operating history of equipment 2a to 2d.

[0024] (Configuration of the sound-making device) Next, the configuration of the sounding device 3 (sounding devices 3a to 3d) of this embodiment will be described.

[0025] Figure 2 shows an example of the schematic configuration of the sound-making device 3 (sound-making devices 3a to 3d). As shown in Figure 2, the sound-making device 3 has a sound-making body 31 and an air intake 32 for efficiently guiding airflow to the sound-making body 31, and is fixed to the outer circumference of the rotating body 21 of the drive unit of the equipment to be monitored. The rotating body 21 is located on the shaft 22 of the drive unit and rotates in conjunction with the rotational drive of the drive unit. When the rotating body 21 rotates, the sound-making device 3 also rotates together with the rotating body 21. When the sound-making device 3 rotates along with the rotation of the rotating body 21, airflow flows into the air intake 32, and the sound-making body 31 emits sound. The sound-making device 3 is, for example, a whistle. By changing the length of the sound-making body 31 in the longitudinal direction (the direction in which the airflow passes), it is possible to change the frequency of the sound emitted by the sound-making body 31. By pre-adjusting the sound emitted by the sound-generating device 3 to an ultrasonic frequency, it is possible to prevent the sound generated by the sound-generating device 3 from becoming noise.

[0026] Figure 3 illustrates the state of the airflow into the air intake 32 of the sound-making device 3 when the rotating body 21 is rotating at high speed. As shown in Figure 3, when the rotating body 21 rotates at high speed, the amount of airflow (airflow rate) into the air intake 32 of the sound-making device 3 increases. The sound-making unit body 31 only produces sound at a certain amount of airflow (there is an airflow range where sound is produced and an airflow range where it is not), so it cannot produce sound if the airflow exceeds that certain amount. Furthermore, if multiple types of sound-making devices 3 are provided according to the rotational speed (rotational speed) of the rotating body 21, there is a problem that the overall size of the equipment will increase.

[0027] Therefore, the sound-making device 3 according to this embodiment is equipped with an airflow adjustment mechanism 5 in the air intake 32 so that it can produce sound even when the rotational speed (number of rotations) of the rotating body 21 changes.

[0028] The following describes the first to third embodiments of the sound-blowing device 3. <First Embodiment> Figure 4 is a diagram showing the configuration of the sound-making device 3 according to the first embodiment, and is a diagram showing the state of the sound-making device 3 when the rotating body 21 (not shown) is rotating at a low speed. As shown in Figure 4, an air intake 32 is connected to the sound-making body 312 of the sound-making unit body 31. An air intake port 321 is provided in this air intake 32. The air intake 32 is approximately square-conical in shape, and is configured such that its size in the height direction (up and down direction in Figure 4) is larger on the air intake port 321 side than on the sound-making unit body 31 side. This allows air to flow into the air intake 32 more effectively when the rotating body 21 is rotating. The airflow that flows into the air intake 32 passes through the air volume adjustment mechanism 5 provided on the sound-making unit body 312 and then flows into the sound-making unit body 31. The airflow that flows into the sound-making unit body 31 flows out from the exhaust port 311, and sound is generated at that time.

[0029] The airflow adjustment mechanism 5 includes a valve V inside the air intake 32. This valve V consists of a plate-shaped member 5a and a bent portion 5b provided at the tip of the plate-shaped member 5a. The plate-shaped member 5a of the valve V is rotatably supported by a shaft portion 5c provided on the side surface of the air intake 32. The shaft portion 5c has a first locking portion 5d that protrudes in a direction substantially perpendicular to the shaft portion 5c on the portion that protrudes to the outside of the air intake 32. One end of a spring 5f is locked to this first locking portion 5d. A second locking portion 5e is provided on the outer surface of the air intake 32, and the other end of the spring 5f is locked to this second locking portion 5e. As a result, the plate-shaped member 5a is biased to rotate in one direction (clockwise around the shaft portion 5c in Figure 4). The end of the plate-shaped member 5a opposite to the bent portion 5b is positioned by a positioning portion (not shown) provided on the inner surface of the air intake 32, and during low-speed rotation, the plate-shaped member 5a is maintained in the state shown in Figure 4.

[0030] Figure 5 shows the state of the sounding device 3 when the rotating body 21 (not shown) is rotating at high speed. As shown in Figure 5, when the rotating body 21 (not shown) is rotating at high speed, the airflow flowing in from the intake port 321 of the air intake 32 hits the bent portion 5b, and the plate-shaped member 5a rotates in the opposite direction to the direction in which it is rotationally biased against the restoring force of the spring 5f (counterclockwise rotation of the shaft portion 5c in Figure 5). As a result, the space above and below the valve V (the space through which the airflow can pass) inside the air intake 32 becomes narrower than when the rotating body 21 is rotating at low speed (Figure 4). As the rotational speed (number of rotations) of the rotating body 21 increases, the amount of rotation (rotation angle) of the plate-shaped member 5a also increases, so the size of the space above and below the valve V (the space through which the airflow can pass) becomes narrower as the rotational speed (number of rotations) of the rotating body 21 increases. As a result, even if the amount of airflow flowing into the air intake 32 increases with the rotational speed of the rotating body 21, the amount of airflow flowing into the sound-making unit body 31 is limited, so the amount of airflow flowing into the sound-making unit body 31 can be kept constant. If the sound-making device 3 does not have an airflow adjustment mechanism 5, the amount of airflow flowing into the sound-making unit body 31 will also change when the rotational speed of the rotating body 21 changes, so the sound-making device 3 will not be able to produce sound stably. However, since the sound-making device 3 of this embodiment is equipped with an airflow adjustment mechanism 5, it can produce sound stably even when the rotational speed (rotational speed) of the rotating body 21 changes.

[0031] In this embodiment, an example in which the airflow adjustment mechanism 5 is provided on the sound-blowing unit body 312 has been described, but the invention is not limited to this. For example, as shown in Figures 10 and 11, the air intake 32 may be connected to the sound-blowing unit body 31, and the airflow adjustment mechanism 5 may be provided inside the air intake 32. Figure 10 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a low speed, and Figure 11 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a high speed. The operation of the airflow adjustment mechanism 5 is the same as in the embodiment described above, so a description is omitted. <Second Embodiment> Figure 6 is a diagram showing the configuration of the sound-blowing device 3 according to the second embodiment, and is a diagram showing the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a low speed. The sound-blowing device 3 in the second embodiment has a different configuration of airflow adjustment mechanism than the first embodiment.

[0032] The sound-blowing device 3 according to the second embodiment includes an airflow adjustment mechanism 50. This airflow adjustment mechanism 50 includes a plate-shaped member 50a rotatably mounted inside the air intake 32 and a shaft portion 50b that pivotally supports the plate-shaped member 50a. Near the outer surface of the air intake 32, a wind receiver 50c is provided to receive the airflow when the rotating body 21 rotates, and this wind receiver 50c is also pivotally supported by the shaft portion 50b, similar to the plate-shaped member 50a. A locking portion 50d is provided on the outer surface of the air intake 32, and one end of a spring 50e is locked to it. The other end of the spring 50e is fixed to one end of a bendable engaging member 50f, and the other end of the engaging member 50f is engaged with the shaft portion 50b. As a result, the plate-shaped member 50a is biased to rotate in one direction (clockwise on the shaft portion 50b in Figure 6). One end of the plate-shaped member 50a (the end on the side of the sound-blowing unit body 31 in Figure 6) is positioned by a positioning part (not shown) provided on the inner surface of the air intake 32, and during low-speed rotation, the plate-shaped member 50a is maintained in the state shown in Figure 6.

[0033] Figure 7 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at high speed. As shown in Figure 7, when the rotating body 21 (not shown) is rotating at high speed, the airflow hits the wind receiver 50c provided near the outer surface of the air intake 32, and the plate-shaped member 50a rotates in the opposite direction to the direction in which it is rotationally biased against the restoring force of the spring 50e (counterclockwise rotation of the shaft portion 50b in Figure 7). As a result, the space above and below the plate-shaped member 50a (the space through which the airflow can pass) inside the air intake 32 becomes narrower than when the rotating body 21 is rotating at low speed (Figure 4). As the rotational speed (number of rotations) of the rotating body 21 increases, the amount of rotation (rotation angle) of the plate-shaped member 50a also increases, so the size of the space above and below the plate-shaped member 50a (the space through which the airflow can pass) becomes narrower as the rotational speed (number of rotations) of the rotating body 21 increases. As a result, even if the amount of airflow flowing into the air intake 32 increases with the rotational speed of the rotating body 21, the amount of airflow flowing into the sound-making unit body 31 is limited, so the amount of airflow flowing into the sound-making unit body 31 can be kept constant. If the sound-making device 3 does not have an airflow adjustment mechanism 50, the amount of airflow flowing into the sound-making unit body 31 will also change when the rotational speed of the rotating body 21 changes, so the sound-making device 3 will not be able to produce sound stably. However, since the sound-making device 3 of this embodiment is equipped with an airflow adjustment mechanism 50, it can produce sound stably even when the rotational speed (rotational speed) of the rotating body 21 changes.

[0034] In this embodiment, an example in which the airflow adjustment mechanism 50 is provided in the sound-blowing section body 312 has been described, but the invention is not limited to this. For example, as shown in Figures 12 and 13, the air intake 32 may be connected to the sound-blowing section body 31, and the airflow adjustment mechanism 50 may be provided inside the air intake 32. Figure 12 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a low speed, and Figure 13 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a high speed. The operation of the airflow adjustment mechanism 50 is the same as in the embodiment described above, so a description is omitted. <Third Embodiment> Figure 8 is a diagram showing the configuration of the sound-blowing device 3 according to the third embodiment, and is a diagram showing the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a low speed. The sound-blowing device 3 in the third embodiment has a different configuration of airflow adjustment mechanism than the first and second embodiments.

[0035] The blower device 3 according to the third embodiment includes an airflow adjustment mechanism 500. This airflow adjustment mechanism 500 includes an opening 500a formed on the bottom surface of the air intake 32 and a valve plate 500b capable of shielding this opening 500a. The end of the valve plate 500b opposite to the intake port 321 is pivotally supported by a hinge 500c. This allows the valve plate 500b to be displaced between a closed position that shields the opening 500a and an open position that does not shield the opening 500a. A weight 500d is fixed to the upper surface of the end of the valve plate 500b on the intake port 321 side. One end of a spring 500e is fixed to this weight 500d. The other end of the spring 500e is fixed to the upper inner surface of the air intake 32.

[0036] Figure 9 shows the state of the sounding device 3 when the rotating body 21 (not shown) is rotating at high speed. As shown in Figure 9, when the rotating body 21 (not shown) is rotating at high speed, the weight 500d provided at the end of the valve plate 500b floats up to the upper side inside the air intake 32 due to the centrifugal force generated as the rotating body 21 rotates. As a result, the valve plate 500b opens and the opening 500a is exposed. Consequently, a portion of the airflow flowing into the air intake 32 is exhausted through the opening 500a, thus limiting the amount of airflow flowing into the sounding unit body 31. As the rotational speed (number of rotations) of the rotating body 21 increases, the amount the valve plate 500b opens also increases. Therefore, even if the amount of airflow flowing into the air intake 32 increases as the rotational speed of the rotating body 21 increases, the amount of airflow flowing into the sounding unit body 31 is limited, and the amount of airflow flowing into the sounding unit body 31 can be kept constant. If the sound-making device 3 does not have an airflow adjustment mechanism 500, the amount of airflow flowing into the sound-making unit body 31 will also change when the rotational speed of the rotating body 21 changes, making it impossible for the sound-making device 3 to produce sound stably. However, since the sound-making device 3 of this embodiment is equipped with an airflow adjustment mechanism 500, it can produce sound stably even when the rotational speed (rotational speed) of the rotating body 21 changes.

[0037] In this embodiment, an example in which the airflow adjustment mechanism 500 is provided on the sound-blowing section body 312 has been described, but the invention is not limited to this. For example, as shown in Figures 14 and 15, the air intake 32 may be connected to the sound-blowing section body 31, and the airflow adjustment mechanism 5 may be provided inside the air intake 32. Figure 14 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a low speed, and Figure 15 shows the state of the sound-blowing device 3 when the rotating body 21 (not shown) is rotating at a high speed. The operation of the airflow adjustment mechanism 500 is the same as in the embodiment described above, so a description is omitted.

[0038] As described above, the sound-making device 3 of this embodiment (first to third embodiment) is a sound-making device 3 provided on the rotating body 21 of a rotating machine (2a to 2d), and comprises a cylindrical air intake 32 having an air intake port 321 into which airflow flows when the rotating body 21 rotates, a sound-making unit body 31 located on the opposite side of the air intake port 321 of the air intake 32 and which makes a sound when airflow that has passed through the air intake 32 flows into it, and an airflow adjustment mechanism (5, 50, 500) provided on the air intake 32, so that it can produce a good sound in accordance with the rotation of the rotating body 21 of the rotating machine (2a to 2d).

[0039] The present invention is not limited to the embodiments described above, and the components can be modified and implemented in practice without departing from the spirit of the invention. Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiments. Moreover, components from different embodiments may be appropriately combined.

[0040] Based on the above description, those skilled in the art may be able to conceive of additional effects and various modifications of the present invention, but the embodiments of the present invention are not limited to the individual embodiments described above. Various additions, modifications, and partial deletions are possible without departing from the conceptual idea and spirit of the present invention derived from the claims and their equivalents.

[0041] Furthermore, not all matters described herein are mandatory requirements. In particular, matters described herein but not included in the claims can be considered optional additional matters.

[0042] It should also be noted that the applicant is only aware of the prior art inventions described in the "Prior Art Documents" section of this specification, and the present invention is not necessarily intended to solve the problems described in those prior art inventions. The problems that the present invention aims to solve should be determined by considering this specification as a whole. For example, if this specification describes that a certain effect is achieved by a particular configuration, it can also be said that the problem that is the inverse of that predetermined effect is solved. However, this does not necessarily mean that such a particular configuration is an essential requirement. [Explanation of Symbols]

[0043] 1. Operation monitoring system 2a~2d equipment 21. Solids of revolution 22 Shaft section 3, 3a~3d blowing device 31. Main body of the sound-making section 32 Air Intake 4 Mike 5, 50, 500 air volume adjustment mechanism 10 Operation monitoring device

Claims

1. A blowing device installed on the rotating body of a rotating machine, A cylindrical air intake having an intake port through which airflow enters when the rotating body rotates, The sound-making section body is located on the opposite side of the air intake from the air intake port, and is sound-making when the airflow that has passed through the air intake flows into it, The sound-blowing unit body or the air intake is provided with an airflow adjustment mechanism, A sound-making device equipped with a blowing mechanism.

2. The airflow adjustment mechanism is provided inside the air intake and has a valve that is rotatable by the airflow flowing into the air intake. The sound-blowing device according to claim 1.

3. The valve is a plate-shaped member, and has a bent portion at the tip of the plate-shaped member. The sound-blowing device according to claim 2.

4. The airflow adjustment mechanism has an air receiver located on the outer surface of the air intake, which is positioned on the rotation axis of the valve. The sound-blowing device according to claim 2.

5. The aforementioned airflow control mechanism is An opening formed on the bottom surface of the aforementioned air intake, A valve plate provided on the inner bottom surface of the air intake, the end opposite to the intake port is pivotally supported, and the valve plate is displaceable between a closed position that shields the opening and an open position that does not shield the opening. A weight provided at the end of the valve plate on the intake port side of the upper surface, A spring, with one end fixed to the weight and the other end fixed to the upper inner surface of the air intake, The sound-blowing device according to claim 1, having the following features.

6. The blowing device according to claim 1, wherein the air intake is substantially truncated square pyramidal in shape.

7. A rotating device comprising a sound-blowing device according to any one of claims 1 to 6.

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