Acoustic tuning material testing fixture and testing device

Abstract

The utility model discloses an acoustic tuning material test fixture and testing arrangement, the fixture is including upper cover and base, is equipped with the loading groove in the base, is equipped with the sound hole in the loading groove, is equipped with the sound hole in the upper cover, and the sound hole is opposite to the sound hole upside and downside, the bottom surface of upper cover is equipped with the positioning convex ring and center pressure plate that protrude to the down, and the center pressure plate and positioning convex ring are located the inside and outside two sides of sound hole, and the center pressure plate is connected with the main part of upper cover, after the upper cover is loaded into the base, and the inside and outside two sides edge of the measured tuning material is pressed by center pressure plate and positioning convex ring respectively. So make tuning material fixed convenient, can be convenient to take out and continue to use after testing, will not waste. Tuning material can test with the shape of normal use, and the test result is more consistent with the acoustic performance of tuning material in actual product. The whole testing arrangement designs the lifting mechanism for placing artificial ear and fixture, can reduce the error that causes when adjusting distance because of the weight is bigger, and the test precision is higher.

Description

Technical Field

[0001] This utility model relates to the field of acoustic testing technology, and in particular to an acoustic tuning material testing fixture and testing device. Background Technology

[0002] Tuning materials such as tuning mesh, tuning paper, and non-woven fabrics play a protective and tuning role in electroacoustics. Different thicknesses of tuning materials have varying air permeability, directly affecting the performance curve of the speaker drivers. Traditionally, the performance parameters of tuning materials such as tuning paper are tested using fabric testing methods employed in the textile industry. However, due to the large testing area and high air pressure of textile fabrics, this method is not comparable to that used in electroacoustics, leading to large testing errors and low accuracy. To address this, professionals in the electroacoustics industry have invented devices specifically for testing the performance parameters of tuning materials such as tuning paper. For example, Chinese invention patent CN109270167B discloses a method and device for testing the performance of breathable paper using electrical signals. This method uses electrical signals to test the performance of breathable paper, calculates and analyzes the delay difference using a dual-channel oscilloscope, and thus determines the air permeability of the paper. The testing steps are simple, low-cost, less affected by external environmental factors, and the test data is accurate.

[0003] However, the device provided by this solution has the following problems: First, it does not provide a method for fixing the breathable paper (i.e., tuning paper). In actual operation, the breathable paper is simply fixed to the plate on which the receiver is mounted by means of adhesive. This fixing method is rather arbitrary, inconvenient to operate, and does not have a good fixing effect on the breathable paper, easily resulting in unevenness. Moreover, the breathable paper can only be torn off and discarded after testing, which will cause material waste. Second, because the breathable paper is small in size in the actual product (such as a speaker) and is not a complete square or circle, it is inconvenient to fix it, and it is impossible to test it with the same shape as the breathable paper in the actual product. This will lead to a difference between the test results and the acoustic performance of the breathable paper in the actual product. Third, the test distance can only be adjusted by adjusting the position of the speaker. However, the speaker is usually heavy, and adjusting it on a moving platform will produce a relatively larger error, thus adversely affecting the test results. Utility Model Content

[0004] This utility model addresses the shortcomings of existing technologies by providing an acoustic tuning material testing fixture and device with a more reasonable structural design, more convenient and faster fixing of the tested tuning material, recyclability of the tested tuning material, and test results that are more consistent with the acoustic performance of actual products.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: an acoustic tuning material testing fixture, comprising a top cover and a base, wherein the base is provided with a loading groove for placing the tuning material to be tested, and the loading groove is provided with a sound outlet hole that runs vertically through the base; the top cover is provided with a vertically through sound inlet hole, the shape of which matches the shape of the tuning material to be tested, and the position of the sound inlet hole is vertically opposite to the sound outlet hole in the base; a downwardly protruding positioning ring and a central pressure plate are provided on the bottom surface of the top cover, the central pressure plate and the positioning ring being located on the inner and outer sides of the sound inlet hole, and the central pressure plate being connected to the main body of the top cover; after the top cover is installed in the base, the central pressure plate and the positioning ring respectively press down on the inner and outer edges of the tuning material to be tested, and the tuning material to be tested separates the sound inlet hole and the sound outlet hole.

[0006] Furthermore, the inner wall of the positioning protrusion ring forms the lower outer wall of the sound inlet hole, and the outer wall of the central pressure plate forms the inner wall of the sound inlet hole; the bottom surface of the loading groove of the base is a flat surface, and the bottom surface of the positioning protrusion ring is flush with the bottom surface of the central pressure plate; both the inner and outer sides of the entrance of the sound inlet hole are set as inclined surfaces so that the entrance of the sound inlet hole forms an flared structure.

[0007] Furthermore, the outer wall dimension of the positioning protrusion ring is matched with the dimension of the loading groove, so that after the positioning protrusion ring is embedded in the loading groove, its outer wall is attached to the groove wall of the loading groove.

[0008] Furthermore, a protruding positioning block is provided in the loading groove of the base, and the positioning block extends from the groove wall of the loading groove toward the center of the loading groove; a positioning groove is provided on the bottom surface of the top cover opposite to the positioning block, and the positioning groove has a structure that is recessed into the positioning protrusion ring. After the top cover is installed into the base, the positioning block is embedded in the positioning groove to form a positioning structure for the top cover and the base.

[0009] Furthermore, the entire sound inlet has an arc-shaped structure, and a connecting arm is provided in the sound inlet. The connecting arm connects the central pressure plate and the positioning protrusion ring, and the connecting arm divides the sound inlet into several segments.

[0010] Furthermore, a recessed assembly groove is provided on the bottom surface of the base, and the assembly groove and the loading groove are connected by the sound outlet.

[0011] An acoustic tuning material testing device includes a support mechanism, a loudspeaker, an artificial ear, and the aforementioned fixture. The loudspeaker is mounted on the support mechanism, and the fixture is mounted on the artificial ear. The pickup hole of the artificial ear is opposite to the sound outlet hole of the fixture. A lifting mechanism is installed on the support mechanism, and the artificial ear together with the fixture is mounted on the lifting mechanism and positioned below the loudspeaker.

[0012] Furthermore, the support mechanism includes an upper plate, a bottom plate, and a support column, with the upper plate and the bottom plate respectively fixed to the upper and lower ends of the support column; a recessed groove is provided in the upper plate, and a horn hole is provided in the groove; the horn is installed in a box whose shape matches the groove to form a full-range loudspeaker, and the loudspeaker is embedded in the groove so that the loudspeaker and the horn hole are aligned.

[0013] Furthermore, the lifting mechanism includes a lifting support, an adjusting nut, a screw, and a guide rod. The screw and guide rod are respectively fixed upright between the upper plate and the bottom plate. The adjusting nut is installed on the screw. The lifting support is connected and fixed to the adjusting nut and is movably assembled with the guide rod through a linear bearing.

[0014] Furthermore, a placement seat is provided on the lifting support, and a clearance opening is provided on the side wall of the placement seat, through which the electrical connector of the artificial ear extends; an upward-protruding connector is provided on the top of the artificial ear, and the connector is inserted into the assembly groove on the bottom surface of the fixture to achieve stable assembly of the fixture and the artificial ear; several support legs are provided at the bottom of the artificial ear, and the artificial ear is placed in the placement seat through the support legs.

[0015] This invention employs a specialized fixture consisting of a top cover and a base to securely hold the tuning material under test. The tuning material requires no adhesive, making fixation convenient and maintaining a high degree of flatness. After testing, it can be easily removed from the fixture and reused as normal tuning material, preventing waste. Furthermore, the fixture is designed to match the structure of the tuning material used in actual products, and the tuning material is tested in its normal usage shape, ensuring that the test results are more consistent with the acoustic performance of the tuning material in the actual product. The entire testing device includes a lifting mechanism for placing the artificial ear and fixture, reducing errors caused by the large weight when adjusting the distance, thus maintaining higher testing accuracy. Attached Figure Description

[0016] Figure 1 This is a structural diagram of the fixture in its closed state according to the present invention;

[0017] Figure 2 This is an exploded view of the fixture of this utility model.

[0018] Figure 3 This is an exploded structural diagram of the fixture of this utility model from another angle;

[0019] Figure 4 This is a structural diagram of the fixture base after the tuning material is installed;

[0020] Figure 5 This is a structural diagram of the testing device of this utility model;

[0021] Figure 6 This is another overall structural view of the testing device of this utility model;

[0022] Figure 7 This is a structural diagram of the testing device of this utility model after the speaker has been removed;

[0023] Figure 8 This is a structural diagram showing the fit between the fixture of this utility model and the artificial ear;

[0024] Figure 9 This is a structural diagram showing the fit between the fixture and the artificial ear from another angle.

[0025] Figure 10 The frequency response curves for seven different tuning paper materials are shown.

[0026] In the diagram, 1 is the fixture, 11 is the top cover, 111 is the sound inlet, 112 is the positioning protrusion ring, 113 is the connecting arm, 114 is the inclined surface, 115 is the positioning groove, 116 is the center pressure plate, 12 is the base, 121 is the loading groove, 122 is the sound outlet, 123 is the positioning block, 124 is the assembly groove, 2 is the artificial ear, 21 is the connector, 22 is the electrical connector, 23 is the support leg, 3 is the speaker, 4 is the placement seat, 41 is the clearance opening, 51 is the top plate, 52 is the bottom plate, 53 is the support column, 54 is the slot seat, 55 is the speaker hole, 61 is the lifting support, 62 is the adjusting nut, 63 is the screw, 64 is the guide rod, and 7 is the sound tuning material being tested. Detailed Implementation

[0027] In this embodiment, refer to Figures 1-4 An acoustic tuning material testing fixture includes a top cover 11 and a base 12. The base 12 has a loading slot 121 for placing the tuning material 7 to be tested, and the loading slot 121 has a sound outlet 122 that extends vertically through the base 12. The top cover 11 has a vertically extending sound inlet 111, the shape of which matches the shape of the tuning material 7 to be tested, such as an arc, a U-shape, a semi-circle, etc. The position of the sound inlet 11 is vertically opposite to the sound outlet 122 in the base 12, and the sound outlet 122 includes multiple small round holes. The components are arranged in the same shape as the sound inlet 111, and their length is approximately the same as that of the sound inlet 111. A downward-protruding positioning ring 112 and a central pressure plate 116 are provided on the bottom surface of the top cover 11. The central pressure plate 116 and the positioning ring 112 are located on the inner and outer sides of the sound inlet 111, and the central pressure plate 116 is connected to the main body of the top cover 11. After the top cover 11 is installed into the base 12, the central pressure plate 116 and the positioning ring 112 respectively press down on the inner and outer edges of the sound-tuning material 7 being tested, ensuring that the sound-tuning material 7 is laid flat. The sound-tuning material 7 being tested separates the sound inlet 11 from the sound outlet 122. The sound from the speaker enters through the sound inlet 11, passes through the sound-tuning material 7, and is then transmitted out through the sound outlet 122 to be received by the artificial ear.

[0028] The inner wall of the positioning protrusion 112 forms the lower outer wall of the sound inlet 111, and the outer wall of the central pressure plate 116 forms the inner wall of the sound inlet 111. The bottom surface of the loading groove 121 of the base 12 is a flat surface, and the bottom surface of the positioning protrusion 112 is flush with the bottom surface of the central pressure plate 116. In this way, the upper cover 11 can pass through the positioning protrusion 112 and the central pressure plate 116 after it is pressed on the base 12. The inner and outer sides of the entrance of the sound inlet 111 are both set as inclined surfaces 114 so that the entrance of the sound inlet 11 forms an flared structure, which can receive the sound emitted by the speaker more fully.

[0029] The outer wall dimension of the positioning protrusion ring 112 matches the dimension of the loading groove 121, so that after the positioning protrusion ring 112 is embedded in the loading groove 121, its outer wall is attached to the groove wall of the loading groove 121, which can improve the stability of the upper cover 11 and the base 12 after assembly.

[0030] A protruding positioning block 123 is provided in the loading groove 121 of the base 12. The positioning block 123 extends from the groove wall of the loading groove 121 toward the center of the loading groove 121. A positioning groove 115 is provided on the bottom surface of the upper cover 11 opposite to the positioning block 123. The positioning groove 115 has a structure that is recessed into the positioning protrusion ring 112. After the upper cover 11 is installed into the base 12, the positioning block 123 is embedded in the positioning groove 115 to form a positioning structure for the upper cover 11 and the base 12, so that the upper cover 11 will not rotate in the base 12.

[0031] The entire sound inlet 11 has an arc-shaped structure. A connecting arm 113 is provided in the sound inlet 11. The connecting arm 113 connects the central pressure plate 116 and the positioning protrusion ring 112 to improve the structural strength of the central pressure plate 116 and the flushness with the positioning protrusion ring 112. The connecting arm 113 divides the sound inlet 111 into three sections.

[0032] A recessed assembly groove 124 is provided on the bottom surface of the base 12, and the assembly groove 121 and the loading groove 124 are connected by the sound outlet 122.

[0033] Reference Figures 5-9 An acoustic tuning material testing device includes a support mechanism, a loudspeaker 3, an artificial ear 2 (the artificial ear 2 uses a standard microphone), and the aforementioned fixture 1. The loudspeaker 3 is mounted on the support mechanism, and the fixture 1 is mounted on the artificial ear 2. The pickup hole of the artificial ear 2 is opposite to the sound outlet hole 122 of the fixture 1. A lifting mechanism is installed on the support mechanism, and the artificial ear 2 together with the fixture 1 is mounted on the lifting mechanism and placed below the loudspeaker so that the distance between the two and the loudspeaker 3 can be adjusted.

[0034] The support mechanism includes an upper plate 51, a bottom plate 52, and a support column 53. The upper plate 51 and the bottom plate 52 are respectively fixed to the upper and lower ends of the support column 53. A recessed slot 54 is provided in the upper plate 51, and a horn hole 55 is provided in the slot 54. The horn is installed in a box (such as a square box or a round box) that matches the shape of the slot 54 to form a full-range speaker 3. The speaker 3 is embedded in the slot 54 so that the speaker is aligned with the horn hole 55. The fixture 1 is located below the horn hole 55.

[0035] The lifting mechanism includes a lifting support 61, an adjusting nut 62, a screw 63, and a guide rod 64. The screw 63 and guide rod 64 are respectively vertically fixed between the upper plate 51 and the bottom plate 52. The adjusting nut 62 is installed on the screw 63. The lifting support 61 is connected and fixed to the adjusting nut 62 and is movably assembled with the guide rod 64 through a linear bearing. When it is necessary to adjust the distance between the fixture 1 (or artificial ear 2) and the speaker 3, the adjusting nut 62 can be rotated in the forward or reverse direction to raise or lower the lifting support 61.

[0036] A placement seat 4 is provided on the lifting support 61. A clearance opening 41 is provided on the side wall of the placement seat 4. The electrical connector 22 of the artificial ear 2 extends out from the clearance opening 41 for connecting wires to power supply and testing equipment. A protruding connector 21 is provided on the top of the artificial ear 2. The connector 21 is inserted into the assembly groove 124 on the bottom surface of the fixture 1. This allows the fixture 1 and the artificial ear 2 to be assembled more stably, while better ensuring airtightness, so that sound can only enter the artificial ear 2 through the sound outlet 122. Several support feet 23 are provided at the bottom of the artificial ear 2. The artificial ear 2 is placed in the placement seat 4 through the support feet 23.

[0037] During testing, select the fixture 1 that matches the tuning material 7 under test. Place the tuning material 7 under test into the loading slot 121 of the base 12, covering all the sound outlets 122 and flattening it. Then, close the top cover 11, and press the tuning material 7 under test with the positioning protrusion 112 and the central pressure plate 116. Place the fixture 1 on the artificial ear 2, insert the connector 21 into the assembly slot 124, and then place the artificial ear 2 together with the fixture 1 into the placement seat 4. Install the speaker 3 into the slot 54 of the upper plate 52. Connect the speaker 3 (using a 32mm miniature speaker) and the artificial ear 2 to the power supply and testing equipment via wires to proceed with subsequent testing. The entire device is tested in an open space to avoid putting additional pressure on the tuning material 7 under test.

[0038] This embodiment uses seven different tuning materials (Y1 tuning paper - Y7 tuning paper) for testing to distinguish their respective air permeability. The test results are as follows: Figure 10As shown. The frequency response curves measured with tuning paper Y1 Limit (2K-4K + / -1.5dB) are shown in Y1, Y2 with tuning paper Y2 Limit (2K-4K + / -1.5dB), Y3 with tuning paper Y3 Limit (2K-4K + / -1.5dB), Y4 with tuning paper Y4 Limit (2K-4K + / -1.5dB), Y5 with tuning paper Y5 Limit (2K-4K + / -1.5dB), Y6 with tuning paper Y6 Limit (2K-4K + / -1.5dB), and Y7 with tuning paper Y7 Limit (2K-4K + / -1.5dB). By comparing the frequency response curves, it can be seen that when controlling the upper and lower limits of + / -1.5dB for tuning papers Y5 and Y6, their test frequency response curves are quite similar, and both can pass this requirement. Further tightening the control to + / -1dB allows for partial detection. Overall, tuning paper Y1 has the highest sensitivity, gradually decreasing from Y2 to Y7, with Y7 having the lowest sensitivity.

[0039] Furthermore, when testing tuning materials, only the tuning materials themselves are the variable throughout the entire testing process. Other components, such as fixtures, testing equipment, loudspeakers, and standard microphones, are identical, thus completely eliminating the influence of other variables on the test results. Figure 10 The frequency response curves shown also demonstrate this point. Each tuning paper from Y1 to Y7 underwent multiple tests, and the frequency response curves obtained from each test were basically consistent with very small deviations that can be ignored.

[0040] The present invention has been described in detail above. The above description is only a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of this application should still fall within the scope of the present invention.

Claims

1. A testing fixture for acoustic tuning materials, characterized in that: The device includes a top cover and a base. The base has a loading slot for holding the tuning material to be tested, and the loading slot has a sound outlet hole that runs vertically through the base. The top cover has a vertically through-hole for sound inlet, the shape of which matches the shape of the tuning material to be tested, and the position of the sound inlet hole is vertically opposite to the sound outlet hole in the base. The bottom surface of the top cover has a downward-protruding positioning ring and a central pressure plate, which are located on the inner and outer sides of the sound inlet hole. The central pressure plate is connected to the main body of the top cover. After the top cover is installed in the base, the central pressure plate and the positioning ring press down on the inner and outer edges of the tuning material to be tested, and the tuning material to be tested separates the sound inlet hole from the sound outlet hole.

2. The acoustic tuning material testing fixture according to claim 1, characterized in that: The inner wall of the positioning protrusion ring forms the lower outer wall of the sound inlet hole, and the outer wall of the central pressure plate forms the inner wall of the sound inlet hole; the bottom surface of the loading groove of the base is a flat surface, and the bottom surface of the positioning protrusion ring is flush with the bottom surface of the central pressure plate; both the inner and outer sides of the entrance of the sound inlet hole are set as inclined surfaces so that the entrance of the sound inlet hole forms an flared structure.

3. The acoustic tuning material testing fixture according to claim 1 or 2, characterized in that: The outer wall dimension of the positioning protrusion ring matches the dimension of the loading groove, so that after the positioning protrusion ring is embedded in the loading groove, its outer wall is attached to the groove wall of the loading groove.

4. The acoustic tuning material testing fixture according to claim 1, characterized in that: A raised positioning block is provided in the loading groove of the base, and the positioning block extends from the groove wall towards the center of the loading groove; a positioning groove is provided on the bottom surface of the top cover opposite to the positioning block, and the positioning groove has a structure that is recessed into the positioning protrusion ring. After the top cover is installed into the base, the positioning block is embedded in the positioning groove to form a positioning structure for the top cover and the base.

5. The acoustic tuning material testing fixture according to claim 1 or 2, characterized in that: The entire sound inlet has an arc-shaped structure. A connecting arm is provided in the sound inlet, which connects the central pressure plate and the positioning protrusion ring. The connecting arm also divides the sound inlet into several segments.

6. The acoustic tuning material testing fixture according to claim 1, characterized in that: A recessed assembly groove is provided on the bottom surface of the base, and the sound outlet hole connects the assembly groove and the loading groove.

7. An acoustic tuning material testing device, comprising a support mechanism, a loudspeaker, and an artificial ear, wherein the loudspeaker is mounted on the support mechanism, characterized in that: It also includes a fixture as described in any one of claims 1-6, the fixture being mounted on the artificial ear, the pickup hole of the artificial ear being opposite to the sound outlet hole of the fixture; a lifting mechanism is mounted on the support mechanism, the artificial ear together with the fixture being mounted on the lifting mechanism and positioned below the speaker.

8. The acoustic tuning material testing device according to claim 7, characterized in that: The support mechanism includes an upper plate, a bottom plate, and a support column. The upper plate and the bottom plate are fixed to the upper and lower ends of the support column, respectively. A recessed groove is provided in the upper plate, and a horn hole is provided in the groove. The horn is installed in a box whose shape matches the groove to form a full-range loudspeaker. The loudspeaker is embedded in the groove so that the loudspeaker and the horn hole are aligned.

9. The acoustic tuning material testing device according to claim 8, characterized in that: The lifting mechanism includes a lifting support, an adjusting nut, a screw, and a guide rod. The screw and guide rod are respectively fixed upright between the upper plate and the bottom plate. The adjusting nut is installed on the screw. The lifting support is connected and fixed to the adjusting nut and is movably assembled with the guide rod through a linear bearing.

10. The acoustic tuning material testing device according to claim 9, characterized in that: A placement seat is provided on the lifting support, and a clearance opening is provided on the side wall of the placement seat, through which the electrical connector of the artificial ear extends; an upward protruding connector is provided on the top of the artificial ear, and the connector is inserted into the assembly groove on the bottom surface of the fixture to achieve stable assembly of the fixture and the artificial ear; several support legs are provided at the bottom of the artificial ear, and the artificial ear is placed in the placement seat through the support legs.

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