Measuring instrument for testing noise or vibration

Abstract

The utility model discloses a measuring instrument for testing noise or vibration, which comprises a measuring instrument body and a plug arranged on the measuring instrument body, a pre-amplifier or a vibration measurer is inserted on the plug, a microphone is arranged on the pre-amplifier, a vibration sensor is arranged in the vibration measurer, sockets are arranged on the pre-amplifier and the vibration measurer, and the front end of the pre-amplifier and the vibration measurer are connected with the microphone. And the socket is provided with an identification signal terminal which is matched with the plug to identify the pre-amplifier or the vibration measurer. According to the scheme, measurement of environment noise and environment vibration is supported, the environment noise can be measured when the pre-amplifier is installed, the environment vibration can be measured when the vibration sensor is installed, and an environment noise testing mode or an environment vibration testing mode is automatically switched. Only one set of sound level meter equipment is needed during detection, environment noise and environment vibration can be measured, convenience is achieved, cost is saved, and the application of the equipment is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of sound level meters, in particular to a measuring instrument for testing noise or vibration. Background Art

[0002] Most existing testing organizations need to measure both ambient noise and vibration, but existing sound level meters only support ambient noise measurements. To measure both, separate sound level meters and vibration analyzers are required, resulting in high testing costs.

[0003] For example, Chinese patent publication number CN116347836A, publication date June 27, 2023, is named "A sound level meter with automatic calibration", which includes a sound level meter body, a sponge cover is movable on the sound level meter body, a connecting seat is clamped on the edge of the sound level meter body, a sound pressure calibrator is fixedly installed on the connecting seat, a sliding rod is slidably provided on the connecting seat, a sleeve is fixedly installed on the sliding rod, and a generator is fixedly installed in the sleeve.

[0004] The disadvantages of the existing patents are that the existing sound level meters can only detect environmental noise and have relatively single uses. Utility Model Content

[0005] The purpose of the utility model is to solve the problem that the existing sound level meter can only detect environmental noise and has a relatively single purpose, and to provide a sound level meter for measuring environmental noise or vibration that can detect both environmental noise and environmental vibration.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A measuring instrument for testing noise or vibration includes a measuring instrument body and a plug mounted on the measuring instrument body. A preamplifier or vibration measuring device is plugged into the plug. A microphone is mounted on the preamplifier. A vibration sensor is mounted in the vibration measuring device. Both the preamplifier and the vibration measuring device are equipped with sockets. The sockets are equipped with identification signal terminals that cooperate with the plug to identify the preamplifier or vibration measuring device. The measuring instrument described in this solution measures environmental noise or vibration by replacing the preamplifier or vibration measuring device mounted on the measuring instrument body. The socket mates with the plug and identifies whether the preamplifier or vibration measuring device is plugged in via the identification signal terminals. The preamplifier is equipped with a microphone that matches the impedance of the microphone with the host input. The microphone converts acoustic signals into electrical signals and inputs them into the measuring instrument body through an electrical connection between the plug and the socket. The vibration measuring device is equipped with a vibration sensor that converts vibration signals into electrical signals and inputs them into the measuring instrument body through an electrical connection between the plug and the socket. Only one measuring instrument is required. By replacing and inserting a preamplifier or vibration measuring device, environmental noise measurement or environmental vibration measurement can be achieved, which improves the use of the measuring instrument, facilitates operation, and saves detection costs.

[0008] Preferably, the socket is further provided with a power supply terminal and a signal terminal that mate with the plug. The measuring instrument body is provided with a battery, and the plug is provided with a power supply port that mates with the power supply terminal. The power supply terminal is electrically connected to the battery, and the plug is plugged into the socket, and the power supply terminal is connected to the power supply port. The battery powers the preamplifier, microphone, and vibration meter. The signal terminal is used to transmit electrical signals.

[0009] Preferably, one end of the preamplifier where the microphone is located is provided with a wind shield, which is used to reduce wind interference with the measurement of the measuring instrument and protect the microphone.

[0010] Preferably, the vibration measuring instrument includes a measuring housing and a support portion disposed within the measuring housing. The support portion is provided with a circuit board, and the vibration sensor is disposed on the support portion. The socket on the vibration measuring instrument is located on the measuring housing and is electrically connected to the circuit board. The vibration measuring instrument is plugged into a plug on the measuring instrument body via the socket on the measuring housing. The measuring housing protects the circuit board and the vibration sensor, and the vibration sensor is electrically connected to the circuit board.

[0011] Preferably, the measuring instrument body includes a main housing and a socket provided on the main housing, the plug is fixed in the socket by a fixing member, the socket passes through the socket and cooperates with the plug. The socket cooperates with the socket, and the socket passes through the socket and is plugged into the plug.

[0012] Preferably, a sealing groove is provided on the inner wall of the socket, a sealing ring is provided in the sealing groove, and the sealing ring is in sealing engagement with the socket, and is used to improve the sealing performance between the socket and the socket, and to prevent water and dust.

[0013] Preferably, the preamplifier and vibration meter are equipped with a TEDS chip, which is electrically connected to the identification signal terminal. The tester body includes a CPU, and the plug and socket cooperate to enable communication between the TEDS chip and the CPU. The sound level meter in this technical solution supports the measurement of both ambient noise and ambient vibration. When the preamplifier is installed, it can measure ambient noise, and when the vibration sensor is installed, it can measure ambient vibration. The CPU in the main housing automatically switches to ambient noise test mode or ambient vibration test mode based on communication with the TEDS chip in the preamplifier or vibration sensor. The testing organization only needs to carry one sound level meter device during testing, which can measure both ambient noise and ambient vibration, which is convenient, cost-effective, and increases the device's versatility. Both the preamplifier and vibration meter are equipped with TEDS chips, which store their respective information and communicate with the CPU via the 1Wire bus. When the corresponding sensor is inserted, the CPU automatically identifies the noise test module and the vibration test module and switches to the corresponding operating mode for measurement.

[0014] Preferably, the measuring instrument body further includes an A / D converter connected to the CPU, a sound separator for filtering the sound signal, and a first selector for connecting the filtered sound signal to the A / D converter. The A / D converter converts the analog signal input from the op amp into a digital signal and transmits it to the CPU via an I2S bus. In this technical solution, the A / D converter includes a left channel and a right channel, and the filtered sound signal is selected by the first selector and connected to one or both of the left and right channels of the A / D converter.

[0015] Preferably, the sound separator includes a first high-pass filter and a low-frequency filter for filtering the sound signal, the low-frequency filter is connected to the A / D converter through an amplifier circuit and an attenuation circuit, and the amplifier circuit or the attenuation circuit is selected by a second selector. In this technical solution, for environmental vibration measurement, the vibration sensor inputs the signal into the signal processing module, the sampling rate of the A / D converter is set to 8000 during vibration measurement, and the measurement frequency range is 1Hz to 80Hz. In order to reduce noise, the signal is passed through a 0.1Hz high-pass filter and a 100Hz low-pass filter. Since the measurement frequency of vibration is very low, in order to avoid mutual interference between the amplifier circuit and the attenuation circuit, the first selector is used to allow the input signal to only be amplified or attenuated at the same time. The amplifier circuit and the attenuation circuit are then connected to the left channel and the right channel of the A / D converter through a second selector. The CPU can only receive the amplified left channel or the attenuated right channel at the same time.

[0016] Preferably, the sound separator further includes a second high-pass filter for filtering the sound signal, the second high-pass filter being connected to an A / D converter via an amplifier circuit and an attenuation circuit. In this technical solution, for environmental noise measurement, the microphone performs impedance transformation on the signal through a preamplifier before inputting it into a signal processing module. Since the noise sampling frequency is 48 kHz, the measurement frequency range is 10 Hz to 20 kHz. To better measure the lower limit, a 1 Hz high-pass filter is used to remove low frequencies. The signal is then connected to the left and right channels of the A / D converter via an amplifier circuit and an attenuation circuit, respectively. At this point, the first selector can connect the noise portion of the signal. The CPU simultaneously receives the left and right channel signals from the A / D converter and automatically selects to implement automatic range switching, with the left channel in the low range and the right channel in the high range. When the left channel signal is below the upper limit of the A / D converter's measurement, the CPU uses the left channel data for calculations. When the left channel signal exceeds the upper limit of the A / D converter's measurement, the CPU uses the right channel data for calculations, thereby achieving a wider measurement range and seamless range switching.

[0017] Preferably, the main housing is provided with buttons and a display screen, both of which are connected to the CPU. The display screen is a touch screen for inputting information and displaying measurement results; the buttons are used to turn the machine on and off.

[0018] Preferably, the main housing is further provided with an SDRAM memory, which is connected to the CPU. In this technical solution, an SCRAM memory is used as a memory extension of the CPU, which can be used to cache measurement data.

[0019] Preferably, the main housing is further provided with an RS232 interface or a wireless communication module connected to the CPU. In this technical solution, communication with the host computer is performed via the RS232 interface; the wireless communication module includes 4G, WIFI and Bluetooth for wireless communication with the host computer or mobile phone.

[0020] Therefore, the present invention has the following beneficial effects: the sound level meter supports the measurement of both ambient noise and ambient vibration. When equipped with a preamplifier, it can measure ambient noise; when equipped with a vibration sensor, it can measure ambient vibration. It automatically switches between ambient noise test mode and ambient vibration test mode. Only one sound level meter is required for testing, and both ambient noise and ambient vibration can be measured, which is convenient, cost-effective, and increases the device's versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural diagram of the utility model for measuring environmental noise.

[0022] Figure 2 It is a structural diagram of the preamplifier in the utility model.

[0023] Figure 3 It is a structural schematic diagram of the utility model for measuring environmental vibration.

[0024] Figure 4 It is a structural schematic diagram of the vibration measuring device in the utility model.

[0025] Figure 5 It is a cross-sectional view of the utility model for measuring environmental noise.

[0026] Figure 6 It is a partial cross-sectional view of the utility model for measuring environmental noise.

[0027] As shown in the picture:

[0028] Main housing 1, display screen 1.1, button 1.2, socket 1.3, sealing groove 1.3.1,

[0029] Preamplifier 2, Microphone 3, Windshield 4,

[0030] Vibration measuring device 5, measuring housing 5.1, circuit board 5.2, vibration sensor 5.3,

[0031] Fixing 6, sealing ring 7,

[0032] Socket 8, identification signal terminal 8.1,

[0033] Plug 9. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the technical solution of the present invention clearer, the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0035] Example 1, as Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 The instrument shown is a noise or vibration measuring instrument, comprising an instrument body and a plug 9 provided on the instrument body. A preamplifier 2 or a vibration measuring device 5 is plugged into the plug 9. The preamplifier 2 is provided with a microphone 3. The vibration measuring device 5 is provided with a vibration sensor 5.3. Both the preamplifier 2 and the vibration measuring device 5 are provided with a socket 8. The socket 8 is provided with an identification signal terminal 8.1 that cooperates with the plug 9 to identify the preamplifier 2 or the vibration measuring device 5.

[0036] Most existing testing organizations need to measure both ambient noise and vibration, but existing sound level meters only support ambient noise measurements. To measure both, separate sound level meters and vibration analyzers are required, resulting in high testing costs. To address the limited use of existing sound level meters, which can only measure ambient noise, a sound level meter is proposed that can measure both ambient noise and vibration.

[0037] The measuring instrument described in the above embodiment measures environmental noise or vibration by replacing the preamplifier 2 or vibration meter 5 plugged into the measuring instrument body. The socket 8 mates with the plug 9, and the preamplifier 2 or vibration meter 5 is identified by the identification signal terminal 8.1. The preamplifier 2 is provided with a microphone 3, which is used to match the impedance of the microphone 3 with the host input. The microphone 3 converts the acoustic signal into an electrical signal, which is then electrically connected to the measuring instrument body via the plug 9 and socket 8. The vibration meter 5 is provided with a vibration sensor 5.3, which converts the vibration signal into an electrical signal, which is then electrically connected to the measuring instrument body via the plug 9 and socket 8. Only one measuring instrument body is required, and environmental noise or vibration measurement can be achieved by replacing the preamplifier 2 or vibration meter 5, thereby enhancing the measuring instrument's utility, facilitating operation, and reducing testing costs.

[0038] In this embodiment, Figure 2 、 Figure 4 、 Figure 5 、 Figure 6 As shown, the socket 8 is also provided with a power supply terminal and a signal terminal that mate with the plug 9. The measuring instrument body is provided with a battery, and the plug 9 is provided with a power supply port that mates with the power supply terminal. The power supply terminal is electrically connected to the battery. The plug 9 is plugged into the socket 8, and the power supply terminal is connected to the power supply port. The battery powers the preamplifier 2, microphone 3, and vibration meter 5. The signal terminal is used to transmit electrical signals.

[0039] Specifically, one end of the preamplifier 2 where the microphone 3 is located is covered with a wind shield 4. The wind shield 4 is used to reduce the interference of wind on the measurement of the measuring instrument and protect the microphone 3 at the same time.

[0040] In this embodiment, the vibration measuring device 5 is further optimized, such as Figure 4As shown, the vibration measuring instrument 5 includes a measuring housing 5.1 and a support portion disposed within the measuring housing 5.1. A circuit board 5.2 is mounted on the support portion, and a vibration sensor 5.3 is disposed on the support portion. A socket 8 on the vibration measuring instrument 5 is located on the measuring housing 5.1 and is electrically connected to the circuit board 5.2. The vibration measuring instrument 5 is plugged into a plug 9 on the measuring instrument body via the socket 8 on the measuring housing 5.1. The measuring housing 5.1 protects the circuit board 5.2 and the vibration sensor 5.3, and the vibration sensor 5.3 is electrically connected to the circuit board 5.2.

[0041] Further optimization of the measuring instrument body, such as Figure 5 、 Figure 6 As shown, the measuring instrument body includes a main housing 1 and a socket 1.3 provided on the main housing 1. The plug 9 is fixed in the socket 1.3 by a fixing member 6. The socket 8 passes through the socket 1.3 and mates with the plug 9. The socket 1.3 mates with the socket 8, and the socket 8 passes through the socket 1.3 and is plugged into the plug 9.

[0042] Further, such as Figure 5 、 Figure 6 As shown, a sealing groove 1.3.1 is provided on the inner wall of the socket 1.3, and a sealing ring 7 is provided in the sealing groove 1.3.1, and the sealing ring 7 is in sealing engagement with the socket 8. The sealing ring 7 is used to improve the sealing between the socket 8 and the socket 1.3, and to prevent water and dust.

[0043] The basic structure is further optimized based on the first embodiment. Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6As shown, a noise or vibration measuring instrument includes a measuring instrument body and a plug 9 mounted on the measuring instrument body. A preamplifier 2 or a vibration measuring device 5 is plugged into the plug 9. The preamplifier 2 is equipped with a microphone 3. The vibration measuring device 5 is equipped with a vibration sensor 5.3. Both the preamplifier 2 and the vibration measuring device 5 are equipped with a socket 8. The socket 8 is equipped with an identification signal terminal 8.1 that cooperates with the plug 9 to identify the preamplifier 2 or the vibration measuring device 5. The preamplifier 2 and the vibration measuring device 5 are equipped with TEDS chips, which are electrically connected to the identification signal terminal 8.1. The measuring instrument body includes a CPU. The plug 9 cooperates with the socket 8 to enable communication between the TEDS chip and the CPU. The sound level meter in this technical solution supports the measurement of both ambient noise and ambient vibration. When the preamplifier 2 is installed, it can measure ambient noise. When the vibration sensor 5.3 is installed, it can measure ambient vibration. The CPU in the main housing 1 automatically switches to an ambient noise test mode or an ambient vibration test mode based on communication with the TEDS chip in the preamplifier 2 or the vibration sensor 5.3. Testing organizations only need to carry one sound level meter during testing, which can measure both ambient noise and vibration. This is convenient, cost-effective, and increases the device's versatility. Both the preamplifier 2 and the vibration meter 5 are equipped with TEDS chips. These chips store their respective information and communicate with the CPU via the 1Wire bus. When the corresponding sensors are inserted, the CPU automatically identifies the noise and vibration test modules and switches to the corresponding operating mode for measurement.

[0044] Specifically, the measuring instrument body also includes an A / D converter connected to the CPU, a sound separator that filters the sound signal, and a first selector that connects the sound signal after the filter to the A / D converter. The A / D converter converts the analog signal input from the op amp into a digital signal and transmits it to the CPU via the I2S bus. In this technical solution, the A / D converter includes a left channel and a right channel. The filtered sound signal is selected by the first selector and connected to one or both of the left and right channels of the A / D converter.

[0045] In this embodiment, the sound separator includes a first high-pass filter and a low-frequency filter for filtering the sound signal. The low-frequency filter is connected to an A / D converter via an amplifier circuit and an attenuation circuit, and the amplifier circuit or the attenuation circuit is selected by a second selector. In this technical solution, for environmental vibration measurement, the vibration sensor 5.3 inputs the signal into the signal processing module. During vibration measurement, the sampling rate of the A / D converter is set to 8000, and the measurement frequency range is 1Hz to 80Hz. To reduce noise, the signal is passed through a 0.1Hz high-pass filter and a 100Hz low-pass filter. Since the vibration measurement frequency is very low, in order to avoid mutual interference between the amplifier circuit and the attenuation circuit, the first selector is used to select only amplification or attenuation of the input signal at the same time. The amplifier circuit and the attenuation circuit are then connected to the left and right channels of the A / D converter via a second selector. The CPU can only receive the amplified left channel or the attenuated right channel at the same time.

[0046] In this embodiment, the sound separator also includes a second high-pass filter for filtering the sound signal. This second high-pass filter is connected to an A / D converter via an amplification circuit and an attenuation circuit. In this technical solution for measuring ambient noise, microphone 3 performs impedance transformation on the signal through preamplifier 2 before inputting it into the signal processing module. Since the noise sampling frequency is 48 kHz, the measurement frequency range is 10 Hz to 20 kHz. In order to better measure the lower limit, the low frequency is filtered out by a 1Hz high-pass filter, and then the signal is connected to the left and right channels of the A / D converter through the amplification circuit and the attenuation circuit respectively. At this time, the first selector can connect to the signal of the noise part. The CPU receives the left and right channel signals of the A / D converter at the same time, and automatically selects to realize the automatic range switching function. The left channel is the low range and the right channel is the high range. When the signal of the left channel is lower than the upper limit of the measurement of the A / D converter, the CPU uses the data of the left channel for calculation. When the signal of the left channel exceeds the upper limit of the measurement of the A / D converter, the CPU will use the data of the right channel for calculation, so as to achieve a larger measurement range. This method can realize seamless range switching.

[0047] In this embodiment, Figure 2 、 Figure 4 、 Figure 5 、 Figure 6 As shown, the socket 8 is also provided with a power supply terminal and a signal terminal that mate with the plug 9. The measuring instrument body is provided with a battery, and the plug 9 is provided with a power supply port that mates with the power supply terminal. The power supply terminal is electrically connected to the battery. The plug 9 is plugged into the socket 8, and the power supply terminal is connected to the power supply port. The battery powers the preamplifier 2, microphone 3, and vibration meter 5. The signal terminal is used to transmit electrical signals.

[0048] Specifically, one end of the preamplifier 2 where the microphone 3 is located is covered with a wind shield 4. The wind shield 4 is used to reduce the interference of wind on the measurement of the measuring instrument and protect the microphone 3 at the same time.

[0049] In this embodiment, the vibration measuring device 5 is further optimized, such as Figure 4 As shown, the vibration measuring instrument 5 includes a measuring housing 5.1 and a support portion disposed within the measuring housing 5.1. A circuit board 5.2 is mounted on the support portion, and a vibration sensor 5.3 is disposed on the support portion. A socket 8 on the vibration measuring instrument 5 is located on the measuring housing 5.1 and is electrically connected to the circuit board 5.2. The vibration measuring instrument 5 is plugged into a plug 9 on the measuring instrument body via the socket 8 on the measuring housing 5.1. The measuring housing 5.1 protects the circuit board 5.2 and the vibration sensor 5.3, and the vibration sensor 5.3 is electrically connected to the circuit board 5.2.

[0050] Further optimization of the measuring instrument body, such as Figure 5 、 Figure 6 As shown, the measuring instrument body includes a main housing 1 and a socket 1.3 provided on the main housing 1. The plug 9 is fixed in the socket 1.3 by a fixing member 6. The socket 8 passes through the socket 1.3 and mates with the plug 9. The socket 1.3 mates with the socket 8, and the socket 8 passes through the socket 1.3 and is plugged into the plug 9.

[0051] Further, such as Figure 5 、 Figure 6 As shown, a sealing groove 1.3.1 is provided on the inner wall of the socket 1.3, and a sealing ring 7 is provided in the sealing groove 1.3.1, and the sealing ring 7 is in sealing engagement with the socket 8. The sealing ring 7 is used to improve the sealing between the socket 8 and the socket 1.3, and to prevent water and dust.

[0052] The main housing 1 is further optimized, such as Figure 5 、 Figure 6 As shown, the main housing 1 is provided with a key 1.2 and a display screen 1.1, both of which are connected to the CPU. The display screen 1.1 is a touch screen 1.1 for inputting information and displaying measurement results; the key 1.2 is used to turn the machine on and off.

[0053] The main housing 1 is further optimized, such as Figure 5 、 Figure 6 As shown, the main housing 1 is further provided with an SDRAM memory, which is connected to the CPU. In this technical solution, an SCRAM memory is used as a memory extension of the CPU to cache measurement data.

[0054] The main housing 1 is further optimized, such as Figure 5 、 Figure 6 As shown, the main housing 1 is also provided with an RS232 interface or wireless communication module connected to the CPU. In this technical solution, communication with the host computer is carried out via the RS232 interface; the wireless communication module includes 4G, WIFI and Bluetooth for wireless communication with the host computer or mobile phone.

[0055] The present invention has the following beneficial effects: the sound level meter supports the measurement of both ambient noise and ambient vibration. When the preamplifier 2 is installed, it can measure ambient noise; when the vibration sensor 5.3 is installed, it can measure ambient vibration. The device automatically switches between ambient noise test mode and ambient vibration test mode. Only one sound level meter is required for testing, and both ambient noise and ambient vibration can be measured. This is convenient, cost-effective, and increases the device's versatility.

[0056] The specific embodiments described above are only preferred implementations of the present invention and are not intended to limit the specific scope of implementation of the present invention. All equivalent changes made to the shape and structure of the present invention should be included in the scope of protection of the present invention.

Claims

1. A noise or vibration measuring instrument, characterized in that: The device comprises a measuring instrument body and a plug arranged on the measuring instrument body, wherein a preamplifier or a vibration measuring device is inserted into the plug, a microphone is arranged on the preamplifier, a vibration sensor is arranged in the vibration measuring device, and sockets are arranged on both the preamplifier and the vibration measuring device, wherein the sockets are provided with an identification signal terminal for cooperating with the plug to identify the preamplifier or the vibration measuring device.

2. A noise or vibration measuring instrument according to claim 1, characterized in that: The socket is also provided with a power supply terminal and a signal terminal that match the plug.

3. A noise or vibration measuring instrument according to claim 2, characterized in that: One end of the preamplifier where the microphone is provided is covered with a wind shield.

4. A noise or vibration measuring instrument according to claim 1, 2 or 3, characterized in that: The vibration measurer includes a measuring shell and a support portion arranged in the measuring shell, a circuit board is provided on the support portion, the vibration sensor is arranged on the support portion, and the socket on the vibration measurer is located on the measuring shell and is electrically connected to the circuit board.

5. A noise or vibration measuring instrument according to claim 1 or 2, characterized in that: The measuring instrument body comprises a main shell and a socket provided on the main shell, the plug is fixed in the socket by a fixing member, and the socket passes through the socket and cooperates with the plug.

6. A noise or vibration measuring instrument according to claim 5, characterized in that: A sealing groove is provided on the inner wall of the socket, a sealing ring is provided in the sealing groove, and the sealing ring is sealed and matched with the socket.

7. A noise or vibration measuring instrument according to claim 1 or 2, characterized in that: The preamplifier and the vibration measuring device are provided with a TEDS chip, the TEDS chip is electrically connected to the identification signal terminal, the measuring instrument body includes a CPU, and the plug and the socket cooperate to enable the TEDS chip to communicate with the CPU.

8. A noise or vibration measuring instrument according to claim 7, characterized in that: The measuring instrument body also includes an A / D converter connected to the CPU, a sound separator for filtering the sound signal, and a first selector for connecting the sound signal after the filter plate to the A / D converter.

9. A noise or vibration measuring instrument according to claim 8, characterized in that: The sound separator includes a first high-pass filter and a low-frequency filter for filtering the sound signal. The low-frequency filter is connected to the A / D converter through an amplifying circuit and an attenuating circuit, and the amplifying circuit or the attenuating circuit is selected by a second selector.

10. The noise or vibration measuring instrument according to claim 9, characterized in that: The sound separator further includes a second high-pass filter for filtering the sound signal, and the second high-pass filter is connected to the A / D converter via an amplifying circuit and an attenuating circuit.

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