CN105163260B - Speaker diaphragm parameter detection method - Google Patents

Abstract

The present invention relates to speaker technology fields, and in particular to a kind of speaker diaphragm parameter detection method used in testing speaker performance, including step：A phantom element is fixedly installed in the top dome part of diaphragm；By inputting the acoustical signal of different frequency, the vibration of diaphragm and phantom element is promoted；The Vibration Condition of diaphragm to be measured is collected using laser, obtains the corresponding frequency Fr of vibration maximum of diaphragm；Calculate the value of the pliable Cms6 in ring part.The detection method of the present invention eliminates the problem of disturbing factor is more in existing detection method, can promote the detection precision of diaphragm parameters, and deviation very little.

Description

Detecting Method of Loudspeaker Diaphragm Parameters

technical field

The invention relates to the technical field of loudspeakers, in particular to a method for detecting parameters of loudspeaker diaphragms used in performance testing of loudspeakers.

Background technique

The loudspeaker diaphragm is an important part of the loudspeaker, which is directly related to F0 in the acoustic performance of the loudspeaker. Therefore, a more accurate detection scheme can find problems before the parts are assembled and reduce the loss of yield. The resonant frequency F0 of the product satisfies: Among them, Cms is the compliance of the surround, which is provided by the part of the surround other than the voice coil; Mms is the vibration mass.

In the prior art, the traditional detection of the Cms of the ring part of the diaphragm of the loudspeaker usually adopts the following method: by assembling the diaphragm into a finished product, testing the F0 of the finished product, and inverting the Cms of the entire diaphragm. At this time, F0 has been determined. Since the diaphragm is composed of a ring part and a dome part during the test, the parameters affecting the Cms of the diaphragm are relatively large, so the test is not accurate enough, resulting in a large defective product and scrapped. large.

Contents of the invention

The purpose of the present invention is to provide a loudspeaker diaphragm parameter detection method capable of accurately measuring and calculating the Cms of the ring part of the diaphragm.

The technical scheme that realizes the object of the present invention is as follows:

Loudspeaker diaphragm parameter detection method, the diaphragm to be tested is composed of a ring part and a dome part, the compliance of the ring part is denoted as Cms6, and the compliance of the dome part is denoted as Cms7; the quality of the diaphragm is denoted as M0;

Step 1, fixedly install a follower part on the spherical top part of the diaphragm, the compliance of the follower part is denoted as Cms10, and the mass of the follower part is denoted as M1, wherein the Young's modulus of the follower part is greater than that of the diaphragm Young's modulus, the thickness of the follow-up part is greater than the thickness of the diaphragm; the quality M1 of the follow-up part is 4-20 times the quality M0 of the diaphragm;

Step 2, by inputting acoustic signals of different frequencies, the vibration of the diaphragm and the moving part is driven;

Step 3, using a laser to collect the vibration of the diaphragm to be tested, and obtaining the frequency Fr corresponding to the maximum vibration value of the diaphragm;

Step 4, the frequency Fr corresponding to the maximum value of the diaphragm vibration satisfies the following conditions,

in, And because the fluctuation of M1+M0 is close to the fluctuation of M1,

Therefore, the value of the compliance Cms6 of the ring part can be calculated.

Further, in order to ensure the accuracy of the detection, the follow-up part is tiled on the upper surface of the dome part.

Adopting the above-mentioned technical scheme, a follower part is fixedly arranged on the dome part of the diaphragm, and the mass M1 of the follower part is several times of the mass M0 of the diaphragm, so as to eliminate the influence of the dome part of the diaphragm on the resonance during the detection process. Contribution, thereby reducing the interference factors of detection and improving the accuracy of detection; the detection method of the present invention eliminates the problem of many interference factors in the existing detection method, can improve the detection accuracy of diaphragm parameters, and the deviation is small.

Description of drawings

Fig. 1 is the structural representation that the diaphragm to be tested is assembled in the loudspeaker;

Fig. 2 is the structural representation that detection method of the present invention detects;

In the accompanying drawings, 1 is the diaphragm, 2 is the voice coil, 3 is the basin frame, 4 is the magnetic circuit, 5 is the front cover, 6 is the ring part, 7 is the dome part, 8 is the sounder, 9 is the laser, 10 is a follower part, and 11 is a casing.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the following will clearly and completely describe the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. Apparently, the described embodiments are some, not all, embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Referring to Fig. 1, the diaphragm 1 is assembled between the frame 3 and the front cover 5, the voice coil 2 is assembled under the middle of the diaphragm, and a magnetic circuit 4 is arranged under the voice coil.

Referring to Fig. 2, a kind of loudspeaker diaphragm parameter detection method provided by the present invention, the diaphragm 1 to be tested is made up of ring part 6 and dome part 7, and the compliancy of ring part is denoted as Cms6, and the compliance of dome part is Cms6. The property is denoted as Cms7; the quality of the diaphragm is denoted as M0; the diaphragm to be tested is assembled in the casing 11, and the bottom of the casing has a sounder 8 that emits different frequencies, and the sounder 8 sounds against the diaphragm and can push the diaphragm produce different resonances;

Step 1, a follow-up part 10 is fixedly arranged on the dome part of the diaphragm. The material of the follow-up part can be the same as that of the dome part of the diaphragm. The follow-up part has compliance and the compliance is recorded as Cms10, the mass of the moving part is recorded as M1, wherein the Young's modulus of the moving part is greater than that of the diaphragm, and the thickness of the moving part is greater than the thickness of the diaphragm; the quality of the moving part M1 is the diaphragm The mass of M0 is 4-20 times; the follower part is tiled on the upper surface of the dome part to enhance the stability of diaphragm vibration and ultimately ensure the accuracy of detection.

Step 2, inputting acoustic signals of different frequencies through the sounder 8 to promote the vibration of the diaphragm and the follow-up part;

Step 3, using the laser 9 to collect the vibration of the diaphragm to be measured, and obtaining the frequency Fr corresponding to the maximum vibration value of the diaphragm;

Step 4, the frequency Fr corresponding to the maximum value of the diaphragm vibration satisfies the following conditions,

in, And because the mass of M1 is greater than M0, the fluctuation of M1+M0 is close to the fluctuation of M1,

Thus, Fr can be simplified as: Therefore, the value of compliance Cms6 of the ring part can be calculated, and the quality of the product can also be detected.

Wherein, the numerals in Cms6, Cms7, M0, Cms10, and M1 in the present invention serve to identify and distinguish, and all of them have special limiting meanings.

In addition, the following method (referred to as the second method) can also be used to realize the detection of the diaphragm parameters: the diaphragm is directly fixed in the housing, and a sound generator is used on one side of the diaphragm to output sound of different frequencies. signal to drive the diaphragm to be tested to vibrate, and use a laser to collect the vibration of the diaphragm to be tested. The frequency corresponding to the maximum value of the vibration is used as the reference Fr. Since the diaphragm is composed of a ring part and a ball top part, the two parts have similar values. The cis Cms of Cms are denoted as Cms6 and Cms7 respectively. However, among them, only Cms6 is a useful part. The vibration mass of the diaphragm is M0, then Fr satisfies: In the actual production process, M0 fluctuates with the fluctuation of film thickness, generally +/-10%; Cms7 of the dome part will change with the change of the actual shape of the dome. Therefore, the Cms6 deviation that needs to be measured in the end is very large. Therefore, the detection accuracy is far lower than the above detection method.

The following provides some detection data of the three detection methods mentioned in this application; wherein, the data in the table below is the data detected by the conventional detection method in the background technology for the diaphragm:

The data in the following table is the data detected by the detection method of the present invention to the diaphragm:

The data in the following table is the data detected by the second detection method in the embodiment of the present invention to the diaphragm:

Conclusion: The new program test of the present invention reduces the influence of Cms7, and the mean value of the result is closer to the actual test result, and the standard deviation is smaller.

Claims (2)

1. The detection method of loudspeaker diaphragm parameters is characterized in that the diaphragm to be tested is composed of a ring part and a dome part, the compliance of the ring part is denoted as Cms6, and the compliance of the dome part is denoted as Cms7; The mass of is denoted as M0; Step 1, fixedly install a follower part on the spherical top part of the diaphragm, the compliance of the follower part is denoted as Cms10, and the mass of the follower part is denoted as M1, wherein the Young's modulus of the follower part is greater than that of the diaphragm Young's modulus, the thickness of the follow-up part is greater than the thickness of the diaphragm; the quality M1 of the follow-up part is 4-20 times the quality M0 of the diaphragm; Step 2, by inputting acoustic signals of different frequencies, the vibration of the diaphragm and the moving part is driven; Step 3, using a laser to collect the vibration of the diaphragm to be tested, and obtaining the frequency Fr corresponding to the maximum vibration value of the diaphragm; Step 4, the frequency Fr corresponding to the maximum value of the diaphragm vibration satisfies the following conditions, <mrow><mi>F</mi><mi>r</mi><mo>=</mo><mfrac><mn>1</mn><mrow><mn>2</mn><mi>&amp;pi;</mi></mrow></mfrac><msqrt><mfrac><mn>1</mn><mrow><mrow><mo>(</mo><mrow><mi>C</mi><mi>m</mi><mi>s</mi><mn>6</mn><mo>+</mo><mfrac><mrow><mi>C</mi><mi>m</mi><mi>s</mi><mn>7</mn><mo>*</mo><mi>C</mi><mi>m</mi><mi>s</mi><mn>10</mn></mrow><mrow><mi>C</mi><mi>m</mi><mi>s</mi><mn>7</mn><mo>+</mo><mi>C</mi><mi>m</mi><mi>s</mi><mn>10</mn></mrow></mfrac></mrow><mo>)</mo></mrow><mo>*</mo><mrow><mo>(</mo><mrow><mi>M</mi><mn>0</mn><mo>+</mo><mi>M</mi><mn>1</mn></mrow><mo>)</mo></mrow></mrow></mfrac></msqrt></mrow> in, And because the fluctuation of M1+M0 is close to the fluctuation of M1, Therefore, the value of the compliance Cms6 of the ring part can be calculated. 2 . The method for detecting parameters of a loudspeaker diaphragm according to claim 1 , wherein the follow-up part is tiled on the upper surface of the dome part. 3 .