English:
[0001] “White” noise is noise having equal intensity at different frequencies (Hz). WO 2017/035388 A2 discloses an acoustic white noise machine and how the frequency or the noise output is changed by opening and closing an adjustable enclosure.
[0004] FIG. 1 is a graph of pink noise on a log-log plot with intensity (dB) on the Y-axis and frequency (Hz) on the X-axis.
[0005] FIG. 2 is a schematic depiction of a fan configured to generate a pink noise sound profile.
[0006] FIG. 3 is a perspective view of a fan according to a particular embodiment with a shutter shown in an open position.
[0007] FIG. 4 is a perspective view of the fan in FIG. 3 with the shutter shown in a closed position.
[0008] FIG. 5 is a top perspective view of a fan wheel for the fan depicted in FIG. 3.
[0009] FIG. 6 is a top plan view of the fan wheel depicted in FIG. 4.
[0010] FIG. 7 is a top plan view of the fan wheel depicted in FIG. 4 in a fan shroud of the fan in FIG. 3.
[0011] FIG. 8 is a pink noise curve plotted with sound pressure level (dB) on the Y-axis and octave bands (Hz) on the X-axis depicting sound measured by a sound meter where the measured sound was generated by a digital pink noise sound generator.
[0012] FIG. 9 depicts the pink noise curve from FIG. 8 and pink noise sound profiles generated by a fan configured to generate pink noise, such as the fan depicted in FIGS. 2 - 4.
[0013] FIG. 2 schematically depicts a fan 20 configured to generate a pink noise sound profile, which will be described in more detail below with reference to FIG. 9. The fan 20 includes a housing 22 having an inlet air vent 24 and an outlet air vent 26. A shutter 28, which can be connected with the housing 22, is movable relative to the housing 22 between an open position (shown in broken lines in FIG. 2) and a closed position (shown in solid lines in FIG. 2). FIGS. 3 and 4 depict a more particular example of the fan 20, however, the fan 20 can take other configurations. FIG. 3 shows the shutter 28 in the open position and FIG. 4 shows the shutter 28 in the closed position. The outlet air vent 26 is open allowing air to exit the housing 22 through the outlet air vent 26 when the shutter 28 is in the open position. The outlet air vent 26 is covered precluding air to exit the housing 22 through the outlet air vent 26 when the shutter 28 is in the closed position.
[0014] With reference back to FIG. 2, the fan 20 further includes a motor 40 having an output shaft 42 connected with a fan wheel 44. More particular examples of the fan wheel 44 are shown in FIGS. 5 - 7. With reference back to FIG. 2, the motor 40 connects with the fan wheel 44 through the output shaft 42 such that when power is delivered to the motor 40 via a power source (not shown), the fan wheel 44 rotates about an axis of rotation 46. The power source can be disposable batteries, rechargeable batteries, and capacitive storage, among others. In some embodiments, the power source can also include a power jack for connection of a power cord to a wall outlet, USB outlet, or other charging port. The power source can be in electrical communication with a controller 48 (schematically depicted in
[0015] With reference to FIG. 5, the fan wheel 44 includes at least one fan blade 50 and is shown as including a plurality of fan blades 50. Each of the fan blades 50 extends in an axial direction from a fan wheel base 52, which is circular in plan view (see FIG. 6) in the illustrated embodiment. Each fan blade 50 includes a radial inner end 54 that is spaced from the axis of rotation 46 of the fan wheel 44. An upper surface 56 of the fan wheel base 52 is planar in the illustrated embodiment. A lower surface 58 of the fan wheel base 52 can also be planar. A circular void is provided between each of the radial inner ends 54 of the respective fan blades 50 and a hub 60 that is concentric with the axis of rotation 46 and defines an opening 62 for attaching the fan wheel 44 to the output shaft 42 (FIG. 2). Each fan blade 50 also includes a radial outer end 64 that terminates along a peripheral edge of the fan wheel base 52. The fan wheel 44 also includes a circumferential upper support 66 located along an upper axial edge 68 of each fan blade 50 at or adjacent the radial outer end 64 of each fan blade 50.
[0016] Each fan blade 50 is a centrifugal fan blade and is forward-curved in the illustrated embodiment, as can be more clearly seen in FIG. 7, which shows air flow in arrows while the fan wheel 44 is rotating expelling air through the outlet air vent 26. For the fan wheel 44 depicted in FIGS. 5 - 7, the fan wheel 44 has a diameter of 100 mm. Each fan blade 50 measures 15 mm in an axial direction between the upper surface 56 of the fan wheel base 52 and the upper axial edge 68. Thirty fan blades 50 are provided on the fan wheel 44. Each fan blade 50 has an inner blade angle of 58.42° and an outer blade angle of 1 1.07°. The above described fan wheel 44 can take other configurations and is not limited to the exact dimensions and configurations described herein.
[0017] FIG. 7 depicts a shroud 80 in which the fan wheel 44 can be positioned. The shroud 80 can include a lower wall 82, which is planar normal to the axis of rotation 46 in the illustrated embodiment. The shroud 80 can also include an involute side wall section 84 with respect to the axis of rotation 46 and a curved side wall section 86 downstream from the involute side wall section 84. The curved side wall section 86 curves inwardly toward the axis of rotation 46 to define a constricted air path 88 upstream from the outlet air vent 26.
[0018] FIG. 8 depicts a pink noise curve 100 generated using a sound meter measuring sound generated by a digital pink noise generator. The pink noise curve 100 depicted in FIG. 8 differs in shape from the pink noise curve depicted in FIG. 1 because the pink noise curve depicted in FIG. 1 shows a logarithmic scale while the pink noise curve 100 shown in FIG. 8 is not a logarithmic scale. The pink noise curve 100 from FIG. 8 is also shown in FIG. 9.
[0019] When the fan wheel 44 is rotating about the axis of rotation 46, the fan 20 generates acoustic pink noise. The housing 22 and the fan blade 50 are configured such that the fan 20 generates a pink noise sound profile, which will be described in more detail below, both when air is exiting the housing 22 through the outlet air vent 26 and when air is not exiting the housing 22 through the outlet air vent 26.
[0020] FIG. 9 depicts four different curves in addition to the pink noise curve 100. A first generated noise curve 102 plots the sound pressure level (dB) measured at different frequencies (Hz) for the fan 20 with the fan wheel 44 rotating and the shutter 28 in the open position (see FIG. 3). A second generated noise curve 104 also plots the sound pressure level (dB) measured at different frequencies (Hz) for the fan 20 with the fan wheel 44 rotating and the shutter 28 in the open position (see FIG. 3). A third generated noise curve 106 plots the sound pressure level (dB) measured at different frequencies (Hz) for the fan 20 with the fan wheel 44 rotating and the shutter 28 in the closed position (see FIG. 4). A fourth generated noise curve 108 also plots the sound pressure level (dB) measured at different frequencies (Hz) for the fan 20 with the fan wheel 44 rotating and the shutter 28 in the closed position (see FIG. 4). The measurements were made using a sound meter in a reverberation chamber.
[0021] As seen in FIG. 9, each generated noise curve 102, 104, 106 and 108 generally follows the pink noise curve 100 in an increasing frequency direction. When considering 31.5 Hz to be a first octave, the third generated noise curve 106 deviates most from the pink noise curve 100 at the second octave (i.e., at 63 Hz). Nevertheless, the deviation at the second octave (63 Hz) of the third generated noise curve 106 from the pink noise curve 100 is within 20% of the measured sound pressure level (dB) at the second octave (63 Hz) for the pink noise curve 100. To the human ear, this 20% deviation is difficult to perceive. Moreover, respective deviations between each generated noise curve 102, 104, 106 and 108 and the pink noise curve 100 from the second octave (63 Hz) in the increasing frequency direction for at least seven additional octaves (e.g. , 125 Hz, 250, Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, and 8000 Hz) are less than 20%.
[0023] As mentioned above, the housing 22 and the fan blade 50 are configured such that the fan 20 generates a pink noise sound profile both when air is exiting the housing 22 through the outlet air vent 26 and when air is not exiting the housing 22 through the outlet air vent 26. The fan 20, however, need not only produce an acoustic pink noise sound profile. The fan 20 can also be configured to produce a digital pink noise sound profile.
[0024] With reference back to FIG. 2, the fan 20 can also include a speaker 130 in communication a pink noise generation device 132. The speaker 130 is in electrical communication with the controller 48 and can be powered by the power source. The speaker 130 communicates with the pink noise generation device 132 such that pink noise can be emitted from the speaker 130. The pink noise generation device 132 can be external from the fan 20 and can include a portable computing device (e.g., a smart phone) capable of running an application that can generate a digital pink noise signal for playing on the speaker 130. Where the pink noise generation device 132 is external to the fan 20, the speaker 130 can be in wireless communication with the pink noise generation device 132. Also, the pink noise generation device 132 can be provided in or on the housing 22 and/or can be in communication with or provided as part of the controller 48. As such, the speaker 130 can communicate with the pink noise generation device 132 via a wired connection.
[0025] When pink noise generation device 132 is communicating with the speaker 130 to play pink noise on the speaker 130, the noise provided by the speaker 130 can follow the pink noise sound profiles described above with reference to FIG. 7. Also, since the pink noise generation device 132 is capable of generating a digital pink noise signal, the pink noise being played on the speaker 130 can even more closely match the pink noise curve depicted in FIG. 8.

中文:
[0001]“白”噪声是在不同频率(Hz)下具有相等强度的噪声。WO2017/035388A2披露了一种声学白噪声机器以及如何通过打开和关闭一个可调节外壳来改变频率或噪声输出。
[0004]图1是在Y轴上具有强度(dB)并且在X轴上具有频率(Hz)的对数-对数图上的粉红噪声的曲线图。
[0005]图2是经配置以产生粉红噪声声音轮廓的风扇的示意性描绘。
[0006]图3是根据特定实施例的风扇的透视图,其中闸板示出为处于打开位置。
[0007]图4是图3中的风扇的透视图,其中闸板示出为处于关闭位置。
[0008]图5是用于图3中描绘的风扇的风扇叶轮的顶部透视图。
[0009]图6是图4中描绘的风扇叶轮的顶部平面图。
[0010]图7是在图3中的风扇的风扇护罩中的图4中所描绘的风扇叶轮的俯视平面图。
[0011]图8是用Y轴上的声压级(dB)和X轴上的倍频带(Hz)绘制的粉红噪声曲线,其描绘由声表测量的声音,其中测量的声音是由数字粉红噪声声音产生器产生。
[0012]图9描绘了来自图8的粉红噪声曲线以及由被配置成用于生成粉红噪声的风扇(如图2至图4中所描绘的风扇)生成的粉红噪声声音轮廓。
[0013]图2示意性地描绘了被配置成用于生成粉红噪声声音轮廓的风扇20,这将在下文中参见图9更详细地描述。风扇20包括具有进气口24和出气口26的壳体22。可与壳体22连接的闸板28可相对于壳体22在打开位置(在图2中以虚线示出)和关闭位置(在图2中以实线示出)之间移动。图3和图4描绘了风扇20的更具体的示例,然而,风扇20可以采取其他配置。图3示出了处于打开位置的闸板28,图4示出了处于关闭位置的闸板28。当闸板28处于打开位置时,出气口26打开,从而允许空气通过出气口26离开壳体22。当闸板28处于关闭位置时,出气口26被覆盖,从而阻止空气通过出气口26离开壳体22。
[0014]返回参考图2,风扇20进一步包括具有与风扇叶轮44连接的输出轴42的电机40。在图5至图7中示出了风扇叶轮44的更具体的实例。返回参见图2,电机40通过输出轴42与风扇叶轮44连接,使得当动力经由电源(未示出)输送到电机40时,风扇叶轮44围绕旋转轴线46旋转。电源可以是一次性电池、可再充电电池和电容存储器等。在一些实施例中,电源还可包括用于将电源线连接到壁装电源插座、USB插座或其他充电端口的电源插孔。如果需要,电源可与控制器48(图2中示意性地示出)电连通,控制器48可控制至电机40的功率传递并控制风扇20上的其他部件。当风扇叶轮44围绕旋转轴线46旋转时,空气通过进气口被吸入壳体22中,并且当闸板28不覆盖出气口26时通过出气口26从壳体22排出。
[0015]参照图5,风扇叶轮44包括至少一个风扇叶片50并且被示出为包括多个风扇叶片50。每个风扇叶片50在轴向方向上从风扇叶轮底座52延伸,该风扇叶轮底座在所示实施例中是圆形的平面视图(见图6)。每个风扇叶片50包括与风扇叶轮44的旋转轴线46间隔开的径向内端54。在所示实施例中,风扇叶轮底座52的上表面56是平面的。风扇叶轮底座52的下表面58也可以是平面的。在各个风扇叶片50的每个径向内端54与轮毂60之间提供了一个圆形空隙,该轮毂与旋转轴线46是同心的并且限定了用于将风扇叶轮44附接到输出轴42上的开口62(图2)。每个风扇叶片50还包括一个径向外端64,该径向外端沿着风扇底座52的外围边缘终止。风扇叶轮44还包括周向上支撑件66,该周向上支撑件沿着每个风扇叶片50的上轴向边缘68定位在每个风扇叶片50的径向外端64处或附近。
[0016]每个风扇叶片50是离心式风扇叶片并且在所示实施例中是向前弯曲的,如可以在图7中更清楚地看到的,该图以箭头示出了当风扇叶轮44旋转从而通过出气口26排出空气时的空气流动。对于图5至图7中所描绘的风扇叶轮44,风扇叶轮44具有100mm的直径。每个风扇叶片50在轴向方向上在风扇叶轮底座52的上表面56与上轴向边缘68之间测量为15mm。在风扇叶轮44上提供了三十个风扇叶片50。每个风扇叶片50的内部叶片角度为58.42°,外部叶片角度为11.07°。上述风扇叶轮44可以采取其他构造并且不限于在此描述的确切尺寸和构造。
[0017]图7描绘了护罩80,风扇叶轮44可以被定位在该护罩中。护罩80可以包括下壁82,该下壁在所示实施例中是平面地垂直于旋转轴线46。护罩80还可以包括相对于旋转轴线46的渐开线侧壁区段84以及在渐开线侧壁区段84的下游的弯曲侧壁区段86。弯曲的侧壁区段86朝向旋转轴线46向内弯曲,以限定出气口26上游的收缩的空气路径88。
[0018]图8描绘了使用测量由数字粉红噪声发生器生成的声音的声表生成的粉红噪声曲线100。图8中描绘的粉红噪声曲线100在形状上不同于图1中描绘的粉红噪声曲线,因为图1中描绘的粉红噪声曲线展示对数标度,而图8中展示的粉红噪声曲线100不是对数标度。图8中的粉红噪声曲线100也在图9中示出。
[0019]当风扇叶轮44围绕旋转轴46旋转时,风扇20产生声粉红噪声。壳体22和风扇叶片50被配置成使得风扇20在空气通过出气口26离开壳体22时和空气不通过出气口26离开壳体22时都产生粉红噪声声音轮廓,这将在下面更详细地描述。
[0020]图9描述了除粉红噪声曲线100之外的四个不同曲线。第一生成的噪声曲线102绘制了在风扇叶轮44旋转并且闸板28处于打开位置(见图3)的情况下风扇20在不同频率(Hz)处测量的声压级(dB)。第二生成的噪声曲线104也绘制了在风扇叶轮44旋转且闸板28处于打开位置(见图3)的情况下风扇20在不同频率(Hz)处测量的声压级(dB)。第三生成的噪声曲线106绘制了在风扇叶轮44旋转并且闸板28处于关闭位置(见图4)的情况下风扇20在不同频率(Hz)处测量的声压级(dB)。第四生成的噪声曲线108也绘制了在风扇叶轮44旋转并且闸板28处于关闭位置(见图4)的情况下风扇20在不同频率(Hz)处测量的声压级(dB)。使用混响室中的声表进行测量。
[0021]如图9中所见,每个生成的噪声曲线102、104、106和108通常在增加的频率方向上遵循粉红噪声曲线100。当将31.5Hz视为第一倍频程时,第三生成的噪声曲线106在第二倍频程处(即,在63Hz处)从粉红噪声曲线100偏离最多。然而,第三生成的噪声曲线106在第二倍频程(63Hz)处与粉红噪声曲线100的偏差在粉红噪声曲线100的第二倍频程(63Hz)处测量的声压级(dB)的20%内。对于人耳而言,这20%的偏差是难以察觉的。此外,对于至少七个额外倍频程(例如,125Hz、250Hz、500Hz、1000Hz、2000Hz、4000Hz和8000Hz),每一个产生的噪声曲线102、104、106和108与粉红噪声曲线100之间在递增频率方向上距第二倍频程(63Hz)的相应偏差小于20%。
[0023]如上所述,壳体22和风扇叶片50被配置成使得当空气通过出气口26离开壳体22时以及当空气没有通过出气口26离开壳体22时,风扇20都生成粉红噪声声音轮廓。然而,风扇20不仅需要产生声学粉红噪声声音轮廓。风扇20还可经配置以产生数字粉红噪声声音轮廓。
[0024]参照回图2,风扇20还可以包括与粉红噪声生成设备132通信的扬声器130。扬声器130与控制器48电通信,并且可以由电源供电。扬声器130与粉红噪声生成设备132通信,使得可以从扬声器130发出粉红噪声。粉红噪声生成设备132可以在风扇20的外部,并且可以包括能够运行能够生成数字粉红噪声信号以便在扬声器130上播放的应用的便携式计算设备(例如,智能电话)。在粉红噪声生成设备132在风扇20外部的情况下,扬声器130可以与粉红噪声生成设备132进行无线通信。另外,粉红噪声产生设备132可设置在壳体22中或上,和/或可与控制器48通信或作为控制器48的一部分设置。照此,扬声器130可经由有线连接与粉红噪声产生设备132通信。
[0025]当粉红噪声产生设备132与扬声器130通信以在扬声器130上播放粉红噪声时,由扬声器130提供的噪声可遵循上文参照图7所描述的粉红噪声声音轮廓。而且,由于粉红噪声生成设备132能够生成数字粉红噪声信号,所以在扬声器130上播放的粉红噪声甚至可以更紧密地匹配图8中描绘的粉红噪声曲线。