Food acoustic acquisition device

Abstract

This invention discloses a food acoustic acquisition device, comprising a support platform, a base plate of the platform, an air-conducted sound signal acquisition component, and a solid-conducted sound emission signal acquisition mechanism. The base plate is placed on the support platform with its bottom open. The air-conducted sound signal acquisition component is installed and fixed at one corner of the support platform and aligned with the base plate of the platform. The solid-conducted sound emission signal acquisition mechanism is magnetically connected to the bottom of the base plate of the platform. This invention effectively improves the repeatability, stability, and ease of assembly and disassembly of food acoustic acquisition.

Description

Technical Field

[0001] This invention relates to the field of sensory quality testing and acoustic acquisition technology for food, specifically to a food acoustic acquisition device. Background Technology

[0002] Crispness, crunchiness, cracking sound, and chewing sound are important sensory attributes of crisp foods such as peanuts, nuts, biscuits, puffed foods, and baked goods. Traditional food sensory evaluation usually relies on trained evaluators to taste and score the food. This method is greatly affected by the evaluator's experience, physical condition, and testing environment, and lacks repeatability, making it difficult to meet the needs of food research and development and quality control for objective and standardized evaluation.

[0003] Existing texture analyzers can acquire force-displacement curves during the crushing process of food, used to characterize mechanical parameters such as hardness, fracture force, and brittleness. However, consumers' judgment of the crispness of food is not solely based on the feeling of force applied to the teeth, but is also significantly influenced by the acoustic signals emitted at the moment of food crushing. When food is crushed or bitten, some sound travels through the air and is received by the ear, while other vibrations travel through the teeth, jawbone, or solid structures of the testing platform. Therefore, auditory sensory fingerprint data of food typically requires the simultaneous acquisition of both airborne sound signals and solid-borne sound emission signals.

[0004] In existing food acoustic acquisition experiments, acoustic emission sensors are used to collect solid-conducted acoustic emission signals. In current experiments, silicone grease, coupling agent, adhesive, or temporary clamping are often used to fix the acoustic emission sensor to the bottom of the test stage. However, relying solely on silicone grease has obvious shortcomings: the thickness and distribution of the silicone grease layer are difficult to keep consistent, the sensor may slip or fall off during long-term testing or under stage vibration, and silicone grease needs to be reapplied and cleaned each time it is disassembled and assembled. In addition, there is a lack of stable pre-tightening force between the sensor and the stage, resulting in insufficient repeatability of the amplitude and frequency response of the solid-conducted acoustic emission signal. Airborne sound signals are collected using microphones, which are often placed on a stand next to the stage. This method is simple in structure, but there is no stable mechanical positioning relationship between the microphone and the stage, and the microphone position is prone to movement. In particular, during the test, the external stand is easily affected by vibration, collision or cable pulling of the test stand. Since the sound of food breaking is a transient non-stationary signal, even a small change in the position of the microphone relative to the breaking point may cause differences in sound pressure peak, spectrum distribution and effective event duration, thus affecting the consistency of auditory fingerprint data. Some microphone stands are also completely fixed around the test equipment to prevent movement, but they are not removable, resulting in insufficient applicability and the inability to select a microphone stand with the appropriate height and angle according to the type of food.

[0005] Therefore, providing a robust and reliable acoustic acquisition device for food is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides a food acoustic acquisition device to at least solve one of the technical problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A food acoustic acquisition device includes a support platform, a base plate of the platform, an air-conducted sound signal acquisition component, and a solid-conducted sound emission signal acquisition mechanism. The base plate of the platform is placed on the support platform and has an open bottom. The air-conducted sound signal acquisition component is installed and fixed at one corner of the support platform and aligned with the base plate of the platform. The solid-conducted sound emission signal acquisition mechanism is magnetically connected to the bottom of the base plate of the platform.

[0008] Furthermore, the solid-conductive acoustic emission signal acquisition mechanism includes a fixed cylinder, an inner sleeve, a top column, a spring, an acoustic emission sensor, and a carbon steel ring. The inner sleeve is threadedly connected to the bottom of the inner cavity of the fixed cylinder. A retaining ring is provided on the inner wall of the inner sleeve near the top. The top column is located inside the inner sleeve and is slidably connected to it. A limiting ring corresponding to the retaining ring is provided in the middle of the outer wall of the top column, and the limiting ring is located below the retaining ring. The spring is sleeved on the top column, with one end abutting against the bottom end of the inner cavity of the fixed cylinder and the other end abutting against the limiting ring, so that the top column extends out of the inner sleeve. The acoustic emission sensor is placed inside the inner cavity of the fixed cylinder, and its bottom end is in contact with the top column. A magnet is embedded and fixed in the bottom of the platform base plate. The carbon steel ring is sleeved on the top of the outer periphery of the fixed cylinder and corresponds to the position of the magnet, so that the fixed cylinder and the platform base plate are magnetically connected.

[0009] Furthermore, the support platform includes a base, two pressure plates, four support columns, and a support plate distributed from bottom to top. The two pressure plates are symmetrically distributed and are both connected to the base by first bolts. The four support columns are arranged in a matrix, and the bottom end of each support column is connected to the corresponding pressure plate by countersunk screws. The threaded post at the top of each support column is threadedly connected to the first threaded hole at the bottom of the support plate. The air-conducting sound signal acquisition component is installed and fixed at one corner of the support plate and aligned with the bottom plate of the platform. The support plate has a through hole running vertically through the platform, and the inner wall of the through hole is provided with an annular step to accommodate the bottom plate of the platform.

[0010] Furthermore, the support plate has two adjacent sides with second threaded holes, and the second bolt is screwed into the second threaded holes until it abuts against the side of the platform base plate.

[0011] Furthermore, the air-conducted sound signal acquisition component includes a microphone mounting bracket and a microphone. The microphone mounting bracket is U-shaped and is clamped to one corner of the support plate. The base plate of the microphone mounting bracket is sleeved on the threaded post to clamp between the support plate and the main body of the support post. The microphone is mounted on the microphone mounting bracket so that the microphone pickup end maintains a predetermined pickup distance from the food sample placement area of ​​the stage base plate.

[0012] Furthermore, the top plate and the bottom plate of the microphone mounting bracket, as well as the support plate, the threaded column, the main body of the support column, the pressure plate and the base corresponding to their positions, all have microphone cable harness passage holes.

[0013] Furthermore, the microphone mounting bracket has a mounting hole, and a shock-absorbing rubber ring is installed in the mounting hole; the microphone is installed in the mounting hole and its periphery is in contact with the shock-absorbing rubber ring.

[0014] Therefore, the present invention provides a food acoustic acquisition device, which, compared with the prior art, has the following beneficial effects: 1) The acoustic emission sensor has been changed from being attached with silicone grease to being fixed with a magnetic bracket, which makes the installation stable, easy to disassemble and assemble, and has good repeatability. In addition, the spring and top column form a stable elastic preload between the acoustic emission sensor and the bottom plate of the stage, which improves the stability of solid-conducted acoustic emission signal acquisition.

[0015] 2) The microphone mounting bracket is fixed by clamping, which ensures reliable position locking and keeps the pickup position fixed during the experiment. At the same time, the microphone mounting bracket is detachable and can be replaced according to the testing needs of different food samples, thus improving its applicability. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 The attached figure is a schematic diagram of the overall structure of a food acoustic acquisition device provided by the present invention; Figure 2 The attached figure is an exploded view of a food acoustic acquisition device provided by the present invention; Figure 3 The attached figure is a schematic diagram of the solid-conductive acoustic emission signal acquisition mechanism provided by the present invention; Figure 4 The attached figure is a cross-sectional view of the solid-conductive acoustic emission signal acquisition mechanism provided by the present invention in conjunction with the base plate of the stage. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figure 1-4 As shown in the figure, this invention discloses a food acoustic acquisition device, which can be installed as an acoustic acquisition accessory on a force-sound texture analyzer, texture analyzer, compression tester, or other food crushing test platform. It includes a support platform 1, a platform base 2, an air-conducted acoustic signal acquisition component 3, and a solid-conducted acoustic emission signal acquisition mechanism 4. The platform base 2 is placed on the support platform 1 with an open bottom. The air-conducted acoustic signal acquisition component 3 is installed and fixed to one corner of the support platform 1 and aligned with the platform base 2. The solid-conducted acoustic emission signal acquisition mechanism 4 is magnetically connected to the bottom of the platform base 2. The air-conducted acoustic signal acquisition component 3 and the solid-conducted acoustic emission signal acquisition mechanism 4 are electrically connected to a data acquisition module to simultaneously acquire air-conducted acoustic signals and solid-conducted acoustic emission signals during the food sample crushing process. This invention effectively improves the repeatability, stability, and ease of assembly and disassembly of food acoustic acquisition.

[0020] Specifically, the solid-state acoustic emission signal acquisition mechanism 4 includes a fixed cylinder 41, an inner sleeve 42, a top column 43, a spring 44, an acoustic emission sensor 45, and a carbon steel ring 46. The inner sleeve 42 is threadedly connected to the bottom of the inner cavity of the fixed cylinder 41. A retaining ring 421 is provided on the inner wall of the inner sleeve 42 near the top. The top column 43 is located inside the inner sleeve 42 and is slidably connected to it. A limiting ring 431 corresponding to the retaining ring 421 is provided in the middle of the outer wall of the top column 43. The limiting ring 431 is located below the retaining ring 421. The spring 44 is sleeved on the top column 43, with one end abutting against the bottom end of the inner cavity of the fixed cylinder 41 and the other end abutting against the limiting ring 431, so that the top column 43 extends out of the inner sleeve 42. The inner sleeve 42 is used to support or limit the spring 44 on the one hand, and to limit the range of motion of the top column 43 on the other hand, preventing the top column 43 and the spring 44 from coming out of the fixed cylinder 41. Furthermore, by adjusting the screw-in depth of the inner sleeve 42, the pre-compression of the spring 44 can be changed within a certain range, so that the acoustic emission sensor 45 can obtain a suitable contact pressure. The acoustic emission sensor 45 is placed inside the inner cavity of the fixed cylinder 41 and its bottom end is in contact with the top column 43, so that the top column 43 applies an elastic pressing force to the acoustic emission sensor 45 toward the bottom surface of the platform base plate 2, and the detection end of the acoustic emission sensor 45 can be tightly attached to the bottom surface of the platform base plate 2. A magnet 21 is embedded and fixed in the bottom of the platform base plate 2, and a carbon steel ring 46 is sleeved on the top of the outer periphery of the fixed cylinder 41 and corresponds to the position of the magnet 21. The magnet 21 and the carbon steel ring 46 together provide an adsorption force, so that the fixed cylinder 41 is adsorbed and fixed to the bottom surface of the platform base plate 2. Thus, the sensor is easier to disassemble, clean and reset, and the sensor contact pressure and installation position are more stable.

[0021] In this embodiment, the acoustic emission sensor 45 can be a piezoelectric acoustic emission sensor, a vibration sensor, an acceleration sensor, or other sensors suitable for acquiring transient vibration signals transmitted through solids.

[0022] It is understandable that an acoustic coupling layer can also be provided between the detection end of the acoustic emission sensor 45 and the bottom surface of the stage base plate 2. The acoustic coupling layer is used to fill the tiny gap between the detection end of the acoustic emission sensor 45 and the bottom surface of the stage base plate 2.

[0023] Specifically, the support platform 1 includes a base 11, two pressure plates 12, four support columns 13, and a support plate 14 distributed from bottom to top. The two pressure plates 12 are symmetrically distributed and are connected to the base 11 by first bolts. The four support columns 13 are arranged in a matrix, and the bottom end of each support column 13 is connected to the corresponding pressure plate 12 by countersunk screws. The threaded post at the top of each support column 13 is threadedly connected to the first threaded hole at the bottom of the support plate 14. The air conduction sound signal acquisition component 3 is installed and fixed at one corner of the support plate 14 and aligned with the base plate 2 of the platform. The support plate 14 has a through hole running vertically through the platform, and the inner wall of the through hole is provided with an annular step to accommodate the base plate 2 of the platform.

[0024] Understandably, the height of the support column 13 located below the microphone mounting bracket 31 is lower than that of the other three support columns 13. Specifically, the height of the support column 13 located below the microphone mounting bracket 31 plus the height of the base plate of the microphone mounting bracket 31 equals the height of the other support columns 13, so as to ensure that the support plate 14 is level.

[0025] To further optimize the technical solution of the present invention, the two adjacent sides of the support plate 14 have second threaded holes 141, and the second bolt is screwed into the second threaded holes 141 until it abuts against the side of the platform base plate 2.

[0026] Specifically, the airborne sound signal acquisition component 3 includes a microphone mounting bracket 31 and a microphone. The microphone mounting bracket 31 is U-shaped and is clamped to one corner of the support plate 14. The base plate of the microphone mounting bracket 31 is fitted onto a threaded post to clamp between the main body of the support plate 14 and the support post 13, reducing the shaking of the microphone mounting bracket 31 during the food breakage test. The microphone is mounted on the microphone mounting bracket 31, maintaining a predetermined pickup distance between the microphone's pickup end and the food sample placement area on the stage base plate 2. In this embodiment, the microphone can be a condenser microphone, a MEMS microphone, an electret microphone, or other pickup devices suitable for acquiring airborne sound.

[0027] Understandably, the data acquisition module includes a first acquisition channel connected to a microphone and a second acquisition channel connected to the acoustic emission sensor 45. The first acquisition channel is used to acquire airborne acoustic signals, and the second acquisition channel is used to acquire solid-borne acoustic emission signals. The two acquisition channels can be triggered and recorded synchronously, thereby obtaining dual-modal acoustic data during the same food crushing process.

[0028] To further optimize the technical solution of the present invention, the top plate and bottom plate of the microphone mounting bracket 31, as well as the support plate 14, threaded column, main body of the support column 13, pressure plate 12 and base 11 corresponding to their positions, are all provided with microphone wire harness passage holes to facilitate the passage of the microphone wire harness. This allows the wire harness to run from inside the support column 13, which can reduce the impact of exposed cables and cable pulling on the microphone mounting bracket 31, and also helps to improve the integration of the overall device.

[0029] To further optimize the technical solution of the present invention, the microphone mounting bracket 31 has a mounting hole, and a shock-absorbing rubber ring is installed in the mounting hole; the microphone is installed in the mounting hole and its outer periphery contacts the shock-absorbing rubber ring to form a circumferential elastic support, which can not only help fix the microphone, but also reduce the mechanical vibration transmitted to the microphone by the support column 13, support plate 14 and platform base plate 2, thereby making the acquisition of air-conducted sound signals more stable.

[0030] The usage process of this invention is as follows: First, the microphone is installed inside the microphone mounting bracket 31. Second, the acoustic emission sensor 45 is installed inside the cavity of the mounting cylinder 41, with the spring 44 and the top column 43 pre-tightening the acoustic emission sensor 45. Then, the mounting cylinder 41 is magnetically attached to a preset position on the bottom surface of the stage base plate 2, so that the detection end of the acoustic emission sensor 45 is in contact with the bottom surface of the stage base plate 2. Subsequently, the food sample to be tested is placed in the sample placement area on the upper surface of the stage base plate 2, and the food sample is compressed and crushed by the pressure head. Finally, the data acquisition module synchronously acquires the air-conducted sound signal output by the microphone and the solid-conducted sound emission signal output by the acoustic emission sensor 45.

[0031] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0032] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A food acoustic harvesting device, characterized in that, The device includes a support platform, a base plate of a platform, an air-conducted sound signal acquisition component, and a solid-conducted sound emission signal acquisition mechanism. The base plate of the platform is placed on the support platform and has an open bottom. The air-conducted sound signal acquisition component is installed and fixed at one corner of the support platform and aligned with the base plate of the platform. The solid-conducted sound emission signal acquisition mechanism is magnetically connected to the bottom of the base plate of the platform.

2. The food acoustic harvesting device of claim 1, wherein, The solid-conductive acoustic emission signal acquisition mechanism includes a fixed cylinder, an inner sleeve, a top column, a spring, an acoustic emission sensor, and a carbon steel ring. The inner sleeve is threaded to the bottom of the inner cavity of the fixed cylinder. A retaining ring is provided on the inner wall of the inner sleeve near the top. The top column is located inside the inner sleeve and is slidably connected to it. A limiting ring corresponding to the retaining ring is provided in the middle of the outer wall of the top column, and the limiting ring is located below the retaining ring. The spring is sleeved on the top column, with one end abutting against the bottom end of the inner cavity of the fixed cylinder and the other end abutting against the limiting ring, so that the top column extends out of the inner sleeve. The acoustic emission sensor is placed inside the inner cavity of the fixed cylinder, and its bottom end is in contact with the top column. A magnet is embedded and fixed in the bottom of the platform base plate. The carbon steel ring is sleeved on the top of the outer periphery of the fixed cylinder and corresponds to the position of the magnet, so that the fixed cylinder and the platform base plate are magnetically connected.

3. The food acoustic harvesting device of claim 1, wherein, The support platform includes a base, two pressure plates, four support columns, and a support plate distributed from bottom to top. The two pressure plates are symmetrically distributed and are both connected to the base by first bolts. The four support columns are arranged in a matrix, and the bottom end of each support column is connected to the corresponding pressure plate by countersunk screws. The threaded post at the top of each support column is threaded to the first threaded hole at the bottom of the support plate. The air-conducting sound signal acquisition component is installed and fixed at one corner of the support plate and aligned with the bottom plate of the platform. The support plate has a through hole running vertically through the platform, and the inner wall of the through hole is provided with an annular step to accommodate the bottom plate of the platform.

4. The food acoustic harvesting device of claim 3, wherein, The support plate has two adjacent sides with second threaded holes, and the second bolt is screwed into the second threaded holes until it abuts against the side of the platform base plate.

5. The food acoustic harvesting device of claim 3, wherein, The air-conducted sound signal acquisition component includes a microphone mounting bracket and a microphone. The microphone mounting bracket is U-shaped and is clamped to one corner of the support plate. The base plate of the microphone mounting bracket is sleeved on the threaded post to clamp between the support plate and the main body of the support post. The microphone is mounted on the microphone mounting bracket so that the microphone pickup end maintains a predetermined pickup distance from the food sample placement area of ​​the stage base plate.

6. The food acoustic harvesting device of claim 5, wherein, The microphone mounting bracket has microphone cable harness passage holes on its top plate, bottom plate, corresponding support plate, threaded post, main body of the support post, pressure plate, and base.

7. The food acoustic harvesting device of claim 5, wherein, The microphone mounting bracket has a mounting hole, and a shock-absorbing rubber ring is installed in the mounting hole; the microphone is installed in the mounting hole and its periphery is in contact with the shock-absorbing rubber ring.

Images