CN114263823A - Microphone positioning device for volume sound source calibration - Google Patents
Microphone positioning device for volume sound source calibration Download PDFInfo
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- CN114263823A CN114263823A CN202111599734.2A CN202111599734A CN114263823A CN 114263823 A CN114263823 A CN 114263823A CN 202111599734 A CN202111599734 A CN 202111599734A CN 114263823 A CN114263823 A CN 114263823A
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- 238000001514 detection method Methods 0.000 description 5
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Abstract
The invention discloses a microphone positioning device for calibrating a volume sound source, which comprises a vertical rod, a plurality of long supporting rods and short supporting rods, wherein the vertical rod is vertically arranged, and the long supporting rods and the short supporting rods are rotatably arranged on the vertical rod and are circumferentially distributed by taking the vertical rod as a center; the vertical rod is provided with at least two positioning supports for respectively positioning each long supporting rod and each short supporting rod, the two positioning supports can move and be positioned in the length direction of the vertical rod, and the end parts of the two positioning supports are detachably connected with the corresponding long supporting rod or the corresponding short supporting rod; the tail ends of the long supporting rods and the short supporting rods are located on the spherical surface of the same hemisphere, and the end parts of the long supporting rods and the short supporting rods are provided with microphone fixing parts used for fixing microphones.
Description
Technical Field
The invention relates to microphone tooling equipment, in particular to a microphone positioning device for calibrating a volume sound source.
Background
The sound transfer function test is a common system sound insulation and absorption test method in the industrial fields of automobile development and the like, a volume sound source is a test device which is usually necessary for implementing the test method, and the device meets the requirement of the whole test method by outputting a stable sound source with a standard sound power spectrum. In order to ensure that the sound signal output by the volume sound source is stable and consistent with expectations in the testing process, the volume sound source is often calibrated by a 'hemisphere method' according to different environmental temperatures. The hemispherical method mainly includes that a plurality of microphones are uniformly distributed on a hemispherical surface with a sound emitting port of a volume sound source as a sphere center, a sound power spectrum of the sound source is calculated through combined test, sound receiving surfaces of the microphones are opposite to the sound emitting port of the volume sound source, and the distance is usually 1m (see fig. 1). When the method is used for testing, the arrangement position of the microphone has higher requirements, a plurality of microphone supports are usually used for repeatedly adjusting and measuring the distance before the volume sound source calibration work so as to meet the space arrangement requirements, time and labor are wasted, the efficiency is very low, and at least nine microphone supports are used, so that the microphone device occupies large storage space when not used and is inconvenient to manage.
At present, chinese patent application No. 201822074052x discloses a microphone consistency detection tool, which includes a simulation mouth and a detection unit disposed below the simulation mouth; the detection unit comprises a sliding table cylinder, a product positioning seat arranged on the sliding table cylinder, two lifting assemblies symmetrically arranged on two sides of the product positioning seat, and a sealing mechanism erected between the two lifting assemblies; during detection, the simulation mouth emits a sound signal, and consistency detection of the microphone of a product to be detected is achieved through the testing system. The tool adopted in the device is not suitable for testing by a hemispherical method, and the whole structure is complex.
Disclosure of Invention
Aiming at the defects of the prior art, the technical problems to be solved by the invention are as follows: how to provide a microphone positioner that simple structure, be convenient for accomodate and can prop up a plurality of microphones on a hemisphere face simultaneously.
In order to solve the technical problems, the invention adopts the following technical scheme:
a microphone positioning device for calibrating a volume sound source is characterized by comprising a vertical rod which is vertically arranged, and a plurality of long supporting rods and short supporting rods which are rotatably arranged on the vertical rod and are circumferentially distributed by taking the vertical rod as a center; at least two positioning supports for respectively positioning each long support rod and each short support rod are arranged on the vertical rod, each positioning support can move and be positioned in the length direction of the vertical rod, and the end part of each positioning support is detachably connected with the corresponding long support rod or the corresponding short support rod; the tail ends of the long supporting rods and the short supporting rods are located on the spherical surface of the same hemisphere, and the end parts of the long supporting rods and the short supporting rods are provided with microphone fixing parts used for fixing microphones. Like this, the long branch and the short branch that set up use the pole setting to set up as central circumference, and the end is equipped with the microphone fixed part that is used for fixed microphone, rotates each branch to certain angle after, can adjust the position of each branch tip to after adjusting required position, support each branch through the location, in order to ensure that each branch tip is in on the sphere of same hemisphere, satisfy the microphone test demand. The positioning support can move up and down and be positioned, and the position can be adjusted in real time according to the rotation angle of each supporting rod, so that the supporting and positioning of the supporting rods at any angle can be realized. The positioning device is simple in overall structure, the supporting rods can rotate to any angle, the positioning support is detachably connected with the supporting rods, and therefore the supporting rods can rotate in the direction of the vertical rods under the condition that the positioning device is not used, the device is stored, and space is effectively saved.
Further, the location props including the sleeve, and circumference is equipped with a plurality of supporting legss on the sleeve outer wall, the supporting legs is the level setting, and each supporting legs length equals, all is equipped with one at the end of every supporting legs with long branch or short strut matched with slant draw-in groove. Like this, the location props through the sleeve cover in the pole setting, and is coaxial with the pole setting, and each supporting legs length is the same, and each supporting legs is just also the same to the interval between each branch to can ensure that the location props the branch that supports and is in on same circumference, and then ensure that each branch tip is in on the same hemisphere face. The mode can effectively reduce the adjusting times of the supporting rod and improve the adjusting precision of the supporting rod. The oblique clamping groove arranged at the end part of the supporting rod can be matched with the rotated supporting rod to support and fix the supporting rod.
Furthermore, the location props and is equipped with two, and one of them is the stock location and props, and another is the quarter butt location and props, and two location props and set up from top to bottom being, and the supporting legs length that the stock location propped is greater than the supporting legs length that the quarter butt location was, and the supporting legs in stock location props and the quarter butt location props are crisscross setting. Like this, two location props and is used for supporting long branch and short branch respectively, and after the crisscross setting, compact structure, mutually noninterfere between long branch and the short branch.
Furthermore, each positioning support is provided with four supporting legs which are distributed in a cross shape, and each supporting leg corresponds to one long supporting rod or one short supporting rod. Like this, the supporting legs distributes evenly, and each supporting legs corresponds with branch to can the quick counterpoint installation.
Furthermore, an external thread is arranged in the middle of the vertical rod, the sleeve is an internal thread sleeve, and the sleeves of the positioning supports are sleeved on the vertical rod and are in threaded fit with the external thread of the vertical rod. Like this, the location props and is connected through sleeve and screw-thread fit between the pole setting, during the use, can realize the location through rotatory sleeve and prop reciprocate and fix a position. Simultaneously, this setting is comparatively steady when removing, can effectively keep the location to prop horizontal migration to ensure its end and branch and correspond the cooperation.
Furthermore, a vertical clamping groove for clamping a microphone is arranged at the lower end of the vertical rod. Like this, the vertical draw-in groove that sets up can be used for fixing a microphone on the pole setting.
Further, circumference is equipped with a plurality ofly and each long branch and the corresponding pull ring of short strut in the pole setting, all is equipped with one on the top of every long branch and short strut and perforates with pull ring matched with, the top of long branch and short strut is worn to establish on the pull ring that corresponds to can rotate from top to bottom around the pull ring. Like this, be connected through the pull ring between pole setting and each branch, and the pole setting overlaps through the perforation and establishes behind the pull ring, can realize around pull ring pivoted purpose from top to bottom, and then adjusts the mounted position of branch.
Furthermore, a hanging buckle is arranged at the top of the vertical rod. Like this, the knot of hanging that sets up can supply positioner and fix with the fixed position of predetermineeing in the laboratory, and it is comparatively convenient to install.
Furthermore, the tail ends of each long supporting rod and each short supporting rod are respectively provided with an arc-shaped sleeve, and a microphone fixing part for inserting a microphone is formed in the middle of each arc-shaped sleeve. In this way, the arc-shaped sleeve at the end part of the supporting rod can be used for inserting a microphone, and therefore the microphone testing position is ensured to be at the set position.
Drawings
FIG. 1 is a graph of a microphone profile during hemispherical testing;
FIG. 2 is a schematic view of an installation structure of a microphone positioning device in an embodiment;
FIG. 3 is an enlarged schematic view of the upper end of the positioning device shown in FIG. 2;
FIG. 4 is an enlarged perspective view of the upper end of the positioning device in the embodiment;
FIG. 5 is a schematic perspective view of an embodiment of a positioning brace;
fig. 6 is an enlarged structural view of an end of the strut in the embodiment.
Detailed Description
The invention is further illustrated with reference to the following figures and examples.
Example (b):
as shown in the figures, the microphone positioning device for calibrating a volume sound source provided by the embodiment includes a vertical rod 1 which is vertically arranged, and a plurality of long supporting rods 2 and short supporting rods 3 which are rotatably installed on the vertical rod 1 and circumferentially distributed by taking the vertical rod 1 as a center; two positioning supports 4 for respectively positioning each long support rod 2 and each short support rod 3 are arranged on the vertical rod 1, each positioning support 4 can move and be positioned in the length direction of the vertical rod 1, and the end part of each positioning support is detachably connected with the corresponding long support rod 2 or the corresponding short support rod 3; the tail ends of the long supporting rods 2 and the short supporting rods 3 are positioned on the spherical surface of the same hemisphere, and the end parts of the long supporting rods and the short supporting rods are provided with microphone fixing parts for fixing microphones. In the specific implementation, one positioning support 4 can correspond to one support rod or two or more support rods, the number of the positioning supports 4 can be increased due to the arrangement, the assembly is complicated, and the uniform positioning is inconvenient.
Further, the positioning support 4 includes a sleeve 41, and a plurality of supporting legs 42 are circumferentially arranged on the outer wall of the sleeve 41, the supporting legs 42 are horizontally arranged, and the length of each supporting leg 42 is equal, and an oblique clamping groove matched with the long support rod 2 or the short support rod 3 is arranged at the end of each supporting leg 42, specifically, the oblique clamping groove in this embodiment is an oblique arc-shaped groove.
As shown in fig. 3 and 4, in the present embodiment, two positioning struts 4 are provided, one of the two positioning struts is a long rod positioning strut, the other one is a short rod positioning strut, the two positioning struts 4 are vertically disposed, the length of the supporting leg 42 of the long rod positioning strut is greater than the length of the supporting leg 42 of the short rod positioning strut, and the long rod positioning strut and the supporting leg 42 of the short rod positioning strut are disposed in a staggered manner. Specifically, each positioning support 4 is provided with four supporting legs 42, the supporting legs 42 are distributed in a cross shape, and each supporting leg 42 corresponds to one long support rod 2 or one short support rod 3.
Furthermore, the middle part of the vertical rod 1 is provided with an external thread, the sleeve 41 is an internal thread sleeve, and the sleeves 41 of the positioning supports 4 are sleeved on the vertical rod 1 and are in threaded fit with the external thread of the vertical rod 1. In specific implementation, a through hole may be formed in the sleeve 41, and the sleeve is fixed to the vertical rod 1 by a fastening bolt and the through hole.
Furthermore, a hanging buckle 11 is arranged at the top of the upright rod 1. The lower end of the upright rod 1 is provided with a vertical clamping groove 13 for clamping a microphone. The circumference is equipped with a plurality ofly and each long branch 2 and the corresponding pull ring 12 of short branch pole 3 on pole setting 1, all is equipped with one on the top of every long branch pole 2 and short branch pole 3 and perforates with pull ring 12 matched with, the top of long branch pole 2 and short branch pole 3 is worn to establish on the pull ring 12 that corresponds to can rotate from top to bottom around pull ring 12. As shown in the figure, the pull ring in the embodiment is U-shaped, the end part of the pull ring is fixedly connected with the vertical rod, and the connection points on the two sides of the end part are arranged up and down, so that the support rods can be effectively ensured to rotate up and down.
As shown in fig. 6, an arc-shaped sleeve is provided at the end of each of the long struts 2 and the short struts 3, and a microphone fixing portion for inserting a microphone is formed at the middle of the arc-shaped sleeve.
An indicating line for assisting the two positioning supports 4 to determine the installation positions is arranged on the upright rod 1, so that a worker can be helped to quickly determine the installation positions of the positioning supports 4, and the positions of the supporting rods can be determined.
When the vertical rod fixing device is used, the top of the vertical rod 1 is fastened at a preset installation position in a laboratory through bolts, the two positioning supports 4 are sequentially screwed in from the lower end of the vertical rod 1 and fixed on a fixing section, the proper position of which is marked in advance, of the vertical rod 1, and the angles between the supporting legs 42 of the two positioning supports 4 are equally divided. Four long supporting rods 2 and four short supporting rods 3 are respectively embedded into oblique clamping grooves at the end parts of two positioning supports 4, and are fixed at the current position due to the constraint of the positioning supports 4, the terminal microphone fixing parts of the short supporting rods 3 are uniformly distributed on a tangent line of half of a hemispherical surface, the terminal microphone fixing parts of the long supporting rods 2 are uniformly distributed on a tangent line of the hemispherical surface, the vertical clamping groove 13 at the bottom of the vertical rod 1 is positioned at the center of the outer surface of the hemispherical surface, and a microphone is inserted into the tail end of each supporting rod to complete installation, so that other test steps can be further completed.
After the use is finished, all the supporting rods are taken down from the tail ends of the positioning supports 4, then the positioning supports 4 are rotated, and after the positioning supports and all the supporting rods are staggered, all the supporting rods rotate to the side of the vertical rod 1 under the action of gravity, so that the folding is realized, and the storage space of the positioning device can be effectively saved.
The invention does not limit the structural use method, for example, as a simplified use mode, the eight support rods in the invention can be reduced to only connect two of long and short support rods, the sound signal acquisition of nine microphone arrangement points is realized by rotating the vertical rod by 1 angle in the experiment, the operation of calibrating the volume sound source by a hemisphere method can also be completed, and the similar changes are non-innovative utilization within the structural scope of the invention and still belong to the protection scope of the invention.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the technical solutions, and although the present invention has been described in detail by referring to the preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention can be made without departing from the spirit and scope of the technical solutions, and all the modifications and equivalent substitutions should be covered by the claims of the present invention.
Claims (9)
1. A microphone positioning device for calibrating a volume sound source is characterized by comprising a vertical rod which is vertically arranged, and a plurality of long supporting rods and short supporting rods which are rotatably arranged on the vertical rod and are circumferentially distributed by taking the vertical rod as a center; at least two positioning supports for respectively positioning each long support rod and each short support rod are arranged on the vertical rod, each positioning support can move and be positioned in the length direction of the vertical rod, and the end part of each positioning support is detachably connected with the corresponding long support rod or the corresponding short support rod; the tail ends of the long supporting rods and the short supporting rods are located on the spherical surface of the same hemisphere, and the end parts of the long supporting rods and the short supporting rods are provided with microphone fixing parts used for fixing microphones.
2. The microphone positioning device for calibrating the volume sound source according to claim 1, wherein the positioning support comprises a sleeve, a plurality of supporting legs are circumferentially arranged on the outer wall of the sleeve, the supporting legs are horizontally arranged, the length of each supporting leg is equal, and an oblique clamping groove matched with the long support rod or the short support rod is arranged at the tail end of each supporting leg.
3. The microphone positioning device for calibrating the volume sound source as claimed in claim 2, wherein there are two positioning struts, one of which is a long rod positioning strut and the other is a short rod positioning strut, the two positioning struts are arranged up and down, the length of the supporting leg of the long rod positioning strut is longer than that of the short rod positioning strut, and the supporting legs of the long rod positioning strut and the short rod positioning strut are arranged in a staggered manner.
4. The microphone positioning device for calibrating the volume sound source as claimed in claim 3, wherein four supporting legs are provided on each positioning support, and the supporting legs are distributed in a cross shape, and each supporting leg corresponds to one long strut or one short strut.
5. The microphone positioning device for calibrating the volume sound source as claimed in claim 2, 3 or 4, wherein an external thread is provided in the middle of the vertical rod, the sleeve is an internal thread sleeve, and the sleeve of each positioning support is sleeved on the vertical rod and is in threaded fit with the external thread of the vertical rod.
6. The microphone positioning device for calibrating the volume sound source as claimed in claim 5, wherein a vertical slot for clamping the microphone is provided at the lower end of the vertical rod.
7. The microphone positioning device for calibrating the volume sound source according to claim 1, 2, 3, 4 or 6, wherein a plurality of pull rings corresponding to the long and short struts are circumferentially arranged on the vertical rod, a through hole matched with the pull ring is formed at the top end of each of the long and short struts, and the top ends of the long and short struts are arranged on the corresponding pull rings in a penetrating manner and can rotate up and down around the pull rings.
8. The microphone positioning apparatus for calibrating a volumetric sound source as recited in claim 7, wherein a hanging buckle is provided on the top of the vertical rod.
9. The microphone positioning device for volume sound source calibration according to claim 1, 2, 3, 4, 6 or 8, wherein an arc-shaped sleeve is provided at the end of each of the long and short struts, and the middle of the arc-shaped sleeve forms a microphone fixing portion for inserting a microphone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111599734.2A CN114263823A (en) | 2021-12-24 | 2021-12-24 | Microphone positioning device for volume sound source calibration |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111599734.2A CN114263823A (en) | 2021-12-24 | 2021-12-24 | Microphone positioning device for volume sound source calibration |
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| CN114263823A true CN114263823A (en) | 2022-04-01 |
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| CN202111599734.2A Pending CN114263823A (en) | 2021-12-24 | 2021-12-24 | Microphone positioning device for volume sound source calibration |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BR7502339U (en) * | 1995-10-10 | 1998-04-28 | Francisco Papandre | Pedestal microphone stand support |
| CN201733416U (en) * | 2010-01-08 | 2011-02-02 | 宁波市鄞州奥创电子有限公司 | Microphone support |
| CN105828259A (en) * | 2016-03-10 | 2016-08-03 | 浙江工业大学 | Umbrella-shaped reconfigurable three-dimensional sensor array |
| KR101683385B1 (en) * | 2015-06-26 | 2016-12-07 | 동서대학교산학협력단 | 360 VR 360 due diligence stereo recording and playback method applied to the VR experience space |
| CN206057554U (en) * | 2016-08-10 | 2017-03-29 | 北京理工大学 | A kind of many spherical microphone array sound field acoustic pressure harvesters |
| CN207978091U (en) * | 2018-03-27 | 2018-10-16 | 中国铁路设计集团有限公司 | A kind of adjustable microphone array holder in position |
| CN109374121A (en) * | 2018-11-23 | 2019-02-22 | 温州市特种设备检测研究院 | A kind of microphone sensor array holder for noise monitoring |
| CN111750976A (en) * | 2020-05-18 | 2020-10-09 | 重庆长安汽车股份有限公司 | Point sound source volume acceleration calibration device and method |
-
2021
- 2021-12-24 CN CN202111599734.2A patent/CN114263823A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BR7502339U (en) * | 1995-10-10 | 1998-04-28 | Francisco Papandre | Pedestal microphone stand support |
| CN201733416U (en) * | 2010-01-08 | 2011-02-02 | 宁波市鄞州奥创电子有限公司 | Microphone support |
| KR101683385B1 (en) * | 2015-06-26 | 2016-12-07 | 동서대학교산학협력단 | 360 VR 360 due diligence stereo recording and playback method applied to the VR experience space |
| CN105828259A (en) * | 2016-03-10 | 2016-08-03 | 浙江工业大学 | Umbrella-shaped reconfigurable three-dimensional sensor array |
| CN206057554U (en) * | 2016-08-10 | 2017-03-29 | 北京理工大学 | A kind of many spherical microphone array sound field acoustic pressure harvesters |
| CN207978091U (en) * | 2018-03-27 | 2018-10-16 | 中国铁路设计集团有限公司 | A kind of adjustable microphone array holder in position |
| CN109374121A (en) * | 2018-11-23 | 2019-02-22 | 温州市特种设备检测研究院 | A kind of microphone sensor array holder for noise monitoring |
| CN111750976A (en) * | 2020-05-18 | 2020-10-09 | 重庆长安汽车股份有限公司 | Point sound source volume acceleration calibration device and method |
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