Method for monitoring noise in elevator car

Abstract

The invention discloses a method for monitoring noise in an elevator car, which comprises the following steps of: acquiring a sound signal of a preset measuring point in the car, and calculating through a preset formula to obtain a sound signal of a car noise evaluation point; the preset formula is S 'V = SM * HM, V, S' V is a sound signal of a car noise evaluation point, SM is a sound signal of a preset measurement point, and HM and V are transfer functions of the preset measurement point; the preset measuring points are arranged on at least one enclosure wall surface in the lift car, and the enclosure wall surface comprises a lift car top, a lift car bottom, a lift car left side, a lift car right side, a lift car inner side and a lift car door side which form a lift car closed space. According to the invention, the sound signal of the elevator car noise evaluation point is indirectly detected, and the conflict with the normal operation of the elevator is avoided. No special installation process is needed, and rapid deployment is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of elevators, and in particular to a method for monitoring noise in an elevator car. Background Art

[0002] As the height of urban buildings continues to increase, the noise problem of elevators, as an indispensable vertical transportation tool in buildings, has become a widely concerned issue, and the industry has formulated the maximum allowable noise value. At the same time, noise is also an important equipment operation parameter, indicating whether the elevator is operating normally. However, after the elevator is installed, the noise can only be measured and evaluated during the regular inspection of the elevator equipment, making it difficult to understand the elevator noise level and evaluate the operating status in real time.

[0003] With the development of the Internet of Things, the noise inside the elevator car can be detected in real time and transmitted to the network, so as to analyze the elevator operation status in real time. According to relevant standards, noise monitoring must place a microphone at a vertical height of 1.5m in the center of the elevator car to measure the noise, that is, the ear position of a general passenger standing posture, which will be defined as the car noise assessment point in the following text. This measurement method is carried out when the elevator is operating normally, and it is difficult to be used for the application of normalized noise monitoring in the car.

[0004] Chinese patent document CN112408135A discloses an elevator equipment data anomaly management system based on remote monitoring, which monitors and determines the operation status of the elevator through an elevator noise database and a noise collection module. The invention focuses on monitoring and diagnosing elevator anomalies by directly collecting noise data at different parts of the elevator, but it is still significantly different from the sound signal measured at the cabin noise assessment point, and cannot intuitively evaluate passengers' perception of noise.

[0005] Therefore, how to obtain the sound signal close to the ear position of the passenger in the daily elevator service process is a technical problem currently faced. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a method for monitoring noise in an elevator car, which collects acoustic signals of preset measuring points in the car and calculates the acoustic signals of car noise evaluation points through a preset formula; the preset formula is S ′ V =S M ·H M,V , where S ′ V is the acoustic signal of the car noise assessment point, S M is the acoustic signal of the preset measuring point, H M,Vis the transfer function of a preset measuring point; the preset measuring point is arranged on at least one surrounding wall surface in the car, and the surrounding wall surface includes six surfaces constituting the closed space of the car: the car top, the car bottom, the car left side, the car right side, the car inside and the car door side.

[0007] Preferably, the transfer function H of the preset measuring point M,V Obtained through simulation or experiment.

[0008] Preferably, the preset measuring point is arranged on the top of the car or above the five-party communication device in the car.

[0009] The present invention also provides a method for monitoring noise in an elevator car, collecting acoustic signals from n preset measuring points in the car, and calculating the acoustic signals of the car noise evaluation points through a preset formula, where n is a positive integer greater than 1; the preset formula is Where S ′ V is the acoustic signal of the car noise assessment point, is the acoustic signal of the ith measuring point, is the transfer function of the ith measuring point, λ i is the acoustic signal weight of the ith measuring point, and satisfies The preset measuring points are arranged on at least one surrounding wall surface in the car, and the surrounding wall surface includes six surfaces constituting the closed space of the car, namely, the car top, the car bottom, the car left side, the car right side, the car inside and the car door side.

[0010] Preferably, the transfer function of the preset measuring point is Obtained through simulation or experiment.

[0011] Preferably, when different measuring points are arranged on the same surrounding wall surface in the car, the closer the distance between the measuring point and the car noise assessment point is, the greater the weight of its acoustic signal is.

[0012] Preferably, when different measuring points are arranged on different surrounding wall surfaces in the car, the method for determining the acoustic signal weights is:

[0013] Step A1, different surrounding wall surfaces are divided into three categories, the first category is the surface consistent with the sound receiving direction of the car noise evaluation point, the second category is the surface at 90° to the sound receiving direction of the car noise evaluation point, and the third category is the surface opposite to the sound receiving direction of the car noise evaluation point;

[0014] Step A2, assigning acoustic signal weights according to the categories corresponding to each wall surface, wherein the acoustic signal weight of the first category surface is greater than that of the second category surface, and the acoustic signal weight of the second category surface is greater than that of the third category surface.

[0015] Preferably, when a surrounding wall surface has at least two measuring points, the measuring points in the surrounding wall surface are assigned sound signal weights according to the distances between the measuring points and the car noise evaluation points. The closer the distance between the measuring points and the car noise evaluation points, the greater the sound signal weights.

[0016] Preferably, the preset measuring point is arranged on the top of the car or above the five-party communication device in the car.

[0017] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in the following aspects:

[0018] Convenience of sensor arrangement: The present invention can arrange the microphone at a position that is easy to fix in the car, and indirectly detect the acoustic signal of the elevator car noise assessment point, avoiding conflicts with the normal operation of the elevator. No special installation process is required, which is convenient for rapid deployment.

[0019] Real-time noise monitoring: The present invention can monitor the noise level in the elevator in real time to ensure that noise changes are captured in time.

[0020] Accuracy and reliability of measurement results: The present invention provides accurate and reliable noise monitoring results through a multi-measurement point evaluation algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0022] Figure 1 A schematic diagram of the locations of preset measurement points for collecting acoustic signals in the car and car noise assessment points in Examples 1 to 3;

[0023] Figure 2 This is a schematic diagram of the technical effect of calculating the acoustic signal of the cabin noise assessment point in Example 2. DETAILED DESCRIPTION

[0024] The following describes the implementation methods of the present invention through specific specific embodiments, and those skilled in the art can fully understand other advantages and technical effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through different specific implementation methods, and the details in this specification can also be applied based on different viewpoints, and various modifications or changes can be made without deviating from the overall design concept of the invention. It should be noted that the following embodiments and the features in the embodiments can be combined with each other in the absence of conflict. The following exemplary embodiments of the present invention can be implemented in a variety of different forms and should not be interpreted as being limited to the specific embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary specific embodiments to those skilled in the art.

[0025] Example 1

[0026] During the noise monitoring process in the elevator car, the most ideal monitoring position is close to the ear position of the passenger's standing posture. For example, relevant standards stipulate that the noise monitoring position is 1.5m at the vertical height of the center of the elevator car. This embodiment defines these noise monitoring positions as car noise assessment points.

[0027] Since the car noise assessment point occupies the passenger space in the car, it is impossible to set a microphone at the car noise assessment point during the daily service operation of the elevator.

[0028] The suitable locations for placing microphones in the car are usually the car walls around the car, the car top and the car bottom. In this embodiment, these suitable locations for placing microphones are defined as the surrounding wall surfaces in the car. The six surrounding wall surfaces in the car constitute the closed space of the car, such as Figure 1 As shown, six surfaces are included: the top of the car, the bottom of the car, the left side of the car, the right side of the car, the inside of the car and the door side of the car.

[0029] This embodiment provides a method for monitoring noise in an elevator car, collecting acoustic signals from preset measuring points in the car, and calculating the acoustic signals of car noise assessment points using a preset formula; the preset formula is S ′ V =S M ·H M,V , where S ′ V is the acoustic signal of the car noise assessment point, S M is the acoustic signal of the preset measuring point, H M,V is a transfer function of a preset measuring point; the preset measuring point is arranged on at least one surrounding wall surface in the car.

[0030] This embodiment collects acoustic signals at positions where microphones are easily arranged through the transfer characteristics of acoustic signals, and then calculates the acoustic signals of the car noise assessment points through transfer functions obtained through simulation and experiments.

[0031] An example of obtaining the transfer function is as follows:

[0032] Take the elevator simulation model with a size of 1500mm*1500mm*2200mm as an example to monitor the traction machine noise. When the traction machine is working, it generates noise, which is transmitted into the car. The sound signal S is measured at the preset measurement point on the car top and the car noise assessment point. M and S V . S M and S V Respectively represent the measured sound signal spectrum, and the transfer function H is obtained by dividing them M,V , the transfer function can be expressed as follows:

[0033] Example 2

[0034] If a single measurement point calculation method is used, when the elevator size or external sound source changes, the transfer function will change, thereby affecting the prediction accuracy. In order to improve the prediction accuracy, this embodiment adopts a weighted average algorithm for multi-measurement point evaluation to eliminate random measurement errors.

[0035] This embodiment provides a method for monitoring noise in an elevator car, collecting acoustic signals from n preset measuring points in the car, and calculating the acoustic signals of the car noise evaluation points through a preset formula, where n is a positive integer greater than 1;

[0036] The preset formula is: Where S ′ V is the acoustic signal of the car noise assessment point, is the acoustic signal of the ith measuring point, is the transfer function of the ith measuring point, λ i is the acoustic signal weight of the ith measuring point, and satisfies

[0037] The method of this embodiment adopts multiple preset measuring points M i Corresponding to multiple groups of acoustic transfer functions Get the predicted signal restored from each single measurement point right Take the weighted average to calculate the acoustic signal of the car noise assessment point. Adjust the acoustic signal weight λ corresponding to different measurement points according to different working conditions. i , which can minimize the prediction error and maximize the accuracy.

[0038] When different measuring points are arranged on the same wall surface in the car, the closer the distance between the measuring point and the car noise evaluation point is, the greater the acoustic signal weight is. For example, when there are three measuring points arranged on the top of the car, the distances between the three measuring points and the car noise evaluation point are 1m, 2m and 3m respectively, and the corresponding acoustic signal weight λ i Set to 1 / 2, 1 / 3 and 1 / 6 respectively.

[0039] Figure 2 The error between the acoustic signal of the car noise evaluation point and the measured value calculated at three measuring points individually, as well as the error between the acoustic signal of the car noise evaluation point and the measured value calculated after weighted averaging are shown. The error calculated after weighted averaging is significantly reduced.

[0040] The preferred sensing points of this embodiment include various positions on the elevator car roof and above the five-party call device in the car. The five-party call device in the car is usually installed at the car control box, and the car control box is usually installed on the car door side, the left side of the car or the right side of the car.

[0041] The sound transfer function from these positions to the center of the car is less affected by changes in the size of the elevator and the position of the external sound source, and the wiring is convenient, making it easy to arrange the acoustic sensors required for long-term monitoring.

[0042] Example 3

[0043] On the basis of Example 2, when different measuring points are arranged on different surrounding wall surfaces in the car, each surrounding wall surface is set with an acoustic signal weight, and the method for determining the acoustic signal weight is as follows:

[0044] Step A1, classify different surrounding wall surfaces into three categories, such as Figure 1 shown.

[0045] The first type is the surface that is consistent with the sound receiving direction of the car noise assessment point, that is, the surface inside the car, which is called the 0° surface in this embodiment;

[0046] The second type is the surface that is 90° to the sound receiving direction of the car noise assessment point, namely, the top of the car, the bottom of the car, the left side of the car, and the right side of the car, a total of 4 surfaces, which are called 90° surfaces in this embodiment;

[0047] The third type is the surface opposite to the sound receiving direction of the car noise assessment point, that is, the surface on the car door side, which is called the 180° surface in this embodiment;

[0048] Step A2, assigning acoustic signal weights according to the categories corresponding to each wall surface, wherein the acoustic signal weight of the first category surface is greater than that of the second category surface, and the acoustic signal weight of the second category surface is greater than that of the third category surface.

[0049] For example, the measurement points are arranged on three different types of wall surfaces. One way to assign the acoustic signal weight according to the category corresponding to each wall surface is to first evenly assign weights to each surface, where the microphone weight on the 0° surface is multiplied by 3 / 2, and the microphone weight on the 180° surface is multiplied by 1 / 2. The weight of the measurement point on the 90° surface = 1-0° surface weight-180° weight. When there are multiple 90° surfaces, the weights are evenly distributed among the multiple surfaces. Multiple points within a surface are then assigned secondary weights based on distance.

[0050] The following are some examples:

[0051] Two measuring points are arranged on the top of the car, and the distances between the measuring points and the car noise assessment points are 1.5m and 2m respectively; one measuring point is arranged on the car door side and one measuring point is arranged inside the car; a total of three wall surfaces and four measuring points are involved.

[0052] The average weight of each wall surface is 1 / 3, but due to the existence of 0° surface and 180° surface, the weighted sum of the measuring points inside the car is 1 / 3*3 / 2=1 / 2, and there is only one measuring point on this surface, so the acoustic signal weight of the measuring point inside the car is λ1=1 / 2; the weighted sum of the measuring points inside the car is 1 / 3*1 / 2=1 / 6, and there is only one measuring point on this surface, so the acoustic signal weight of the measuring point on the car door side is λ2=1 / 6; the weighted sum of the measuring points on the top of the car is 1-1 / 2-1 / 6=1 / 3, and there are 2 measuring points on this surface, so λ 31 +λ 32 =1 / 3, and then distribute the weights according to the distance principle, λ 31 =2 / (1.5+2)*1 / 3=0.17,λ 32 =1.5 / (1.5+2)*1 / 3=0.13.

[0053] This embodiment classifies and sets the sound signal weights according to the different sound receiving directions of the microphones on the surrounding wall surface, thereby reducing the influence of different microphone pointing directions on the detection results.

[0054] The present invention has been described in detail above through specific implementation modes and embodiments, but these do not constitute limitations of the present invention. Without departing from the principles of the present invention, those skilled in the art may also make many variations and improvements, which should also be regarded as the protection scope of the present invention.

Claims

1. A method for monitoring noise in an elevator car, characterized in that: The acoustic signal of the preset measuring point in the car is collected, and the acoustic signal of the car noise assessment point is calculated by a preset formula; the preset formula is S′ V =S M ·H M，V , where S′ V is the acoustic signal of the car noise assessment point, S M is the acoustic signal of the preset measuring point, H M，V is the transfer function of a preset measuring point; the preset measuring point is arranged on at least one surrounding wall surface in the car, and the surrounding wall surface includes six surfaces constituting the closed space of the car: the car top, the car bottom, the car left side, the car right side, the car inside and the car door side.

2. The method for monitoring noise in an elevator car according to claim 1, characterized in that: Transfer function H of preset measuring point M，V Obtained through simulation or experiment.

3. The method for monitoring noise in an elevator car according to claim 1, characterized in that: The preset measuring point is arranged on the top of the car or above the five-party communication device in the car.

4. A method for monitoring noise in an elevator car, characterized in that: Acoustic signals of n preset measuring points in the car are collected, and the acoustic signals of the car noise assessment points are calculated by a preset formula, where n is a positive integer greater than 1; The preset formula is: where S′ V is the acoustic signal of the car noise assessment point, is the acoustic signal of the ith measuring point, is the transfer function of the ith measuring point, λ i is the acoustic signal weight of the ith measuring point, and satisfies The preset measuring points are arranged on at least one surrounding wall surface in the car, and the surrounding wall surface includes six surfaces constituting the closed space of the car: the car top, the car bottom, the car left side, the car right side, the car inside and the car door side.

5. The method for monitoring noise in an elevator car according to claim 4, characterized in that: Transfer function of preset measuring points Obtained through simulation or experiment.

6. The method for monitoring noise in an elevator car according to claim 4, characterized in that: When different measuring points are arranged on the same surrounding wall surface in the car, the closer the distance between the measuring point and the car noise assessment point is, the greater the weight of its acoustic signal is.

7. The method for monitoring noise in an elevator car according to claim 4, characterized in that: When different measuring points are arranged on different surrounding walls in the car, the method for determining the acoustic signal weight is as follows: Step A1, different surrounding wall surfaces are divided into three categories, the first category is the surface consistent with the sound receiving direction of the car noise evaluation point, the second category is the surface at 90° to the sound receiving direction of the car noise evaluation point, and the third category is the surface opposite to the sound receiving direction of the car noise evaluation point; Step A2, assigning acoustic signal weights according to the categories corresponding to each wall surface, wherein the acoustic signal weight of the first category surface is greater than that of the second category surface, and the acoustic signal weight of the second category surface is greater than that of the third category surface.

8. The method for monitoring noise in an elevator car according to claim 4, characterized in that: When a wall surface has at least two measuring points, the acoustic signal weights of the measuring points in the wall surface are allocated according to the distance between the measuring points and the car noise evaluation point. The closer the distance between the measuring points and the car noise evaluation point, the greater the acoustic signal weight.

9. The method for monitoring noise in an elevator car according to claim 4, characterized in that: The preset measuring point is arranged on the top of the car or above the five-party communication device in the car.

Images