Process Preparation Method of a Sound Lens in an Image Sonar

Abstract

The present invention discloses a technology belonging to the field of acoustic lenses, specifically a process preparation method for an acoustic lens in an image sonar, and the specific steps are as follows: Use a machining component to form lens surfaces on the opposite end faces of two plastics to obtain a lens skeleton. Bond the two lens skeletons together by bonding, and leave a pouring hole at the top between the two groups of lens skeletons. Inject a sound-refracting material between the two lens skeletons through the pouring hole, seal the pouring hole with a sealing material, and paste a matching layer on the opposite ends of the two lens skeletons to obtain a lens. The acoustic lens group made by the present invention has the characteristics of a strong structure and low attenuation. The design of the lens group ensures a large aperture, a wide field of view, and corrected spherical aberration and chromatic aberration of the imaging system, and can achieve good imaging effects.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic lenses, and particularly to a process preparation method of an acoustic lens in an image sonar. Background Art

[0002] An acoustic lens is an acoustic element that can converge or diverge sound waves, similar to a lens in optics. In an image sonar, when the frequency is high and the wavelength of the sound wave is much smaller than the acoustic aperture, the sound wave can be regarded as approximately straight-line propagation. Thus, an acoustic lens can be designed using a method similar to geometric optics, and a transducer element is placed behind the acoustic lens to achieve fine acoustic imaging.

[0003] Similar to an optical lens, an acoustic lens must be made of a material that is sound-transmissive and has a refractive index different from that of the medium. To project as much sound wave as possible onto the transducer element, the acoustic lens material must have as low an attenuation characteristic as possible and an acoustic impedance as close as possible to that of the medium. This requirement poses extremely high demands on the design and preparation of the acoustic lens material.

[0004] Acoustic lens materials can be divided into two categories: liquid and solid. The characteristics of liquid materials are that the attenuation is usually low, and it is convenient to achieve different refractive indices and acoustic impedances by modifying the formula. However, since liquids cannot be formed, they are very inconvenient to use, so their applications are extremely few. Solid materials can be divided into two categories: plastics and rubbers. The former is convenient for forming and has a strong structure, but usually has a large attenuation, poor impedance matching, and only a few materials such as ABS, PMP, PS, and epoxy resin can be selected, and precise adjustment of the refractive index cannot be achieved; the latter has low attenuation, but is too soft and inconvenient to use. Therefore, a process preparation method of an acoustic lens in an image sonar is invented. Summary of the Invention

[0005] In view of the above and / or existing problems in a process preparation method of an acoustic lens in an image sonar, the present invention is proposed.

[0006] Therefore, the object of the present invention is to provide a process preparation method of an acoustic lens in an image sonar, which can solve the above-mentioned existing problems.

[0007] To solve the above technical problems, according to one aspect of the present invention, the following technical solutions are provided:

[0008] A process preparation method of an acoustic lens in an image sonar, which specifically includes the following steps:

[0009] Step 1: Form lens surfaces on the opposite end faces of two plastics through a machining component to obtain a lens skeleton;

[0010] Step 2: Open a semi-circular hole communicating with the lens surface at the top of the lens skeleton. After that, bond the two lens skeletons together by bonding method. At this time, the two semi-circular holes will form a circular hole, which is the pouring hole.

[0011] Step 3: Inject the sound-refracting material between the two lens skeletons through the pouring hole.

[0012] Step 4: Seal the pouring hole with a sealing material.

[0013] Step 5: Paste a matching layer on the opposite ends of the two lens skeletons to obtain the lens.

[0014] As a preferred solution of the process preparation method of a sound lens in the image sonar described in the present invention, wherein: the plastic in Step 1 is a sound-transmitting plastic, and the sound-transmitting plastic is a plastic that is hard, has excellent sound-transmitting performance, and can realize large-scale injection molding production.

[0015] As a preferred solution of the process preparation method of a sound lens in the image sonar described in the present invention, wherein: the sound-refracting material refers to a liquid or liquid rubber with a refractive index different from that of the sound-transmitting plastic, small attenuation, and can be formed by pouring. By adjusting the formula and reinforcing materials, the poured sound-refracting material can adjust the refractive index and acoustic impedance within a wide range, so as to realize sound lenses with different performances.

[0016] As a preferred solution of the process preparation method of a sound lens in the image sonar described in the present invention, wherein: if the sound-refracting material is liquid rubber in Step 4, the pouring hole does not need to be sealed.

[0017] As a preferred solution of the process preparation method of a sound lens in the image sonar described in the present invention, wherein: the sealing material in Step 4 is glue or plastic.

[0018] As a preferred solution of the process preparation method of a sound lens in the image sonar described in the present invention, wherein: a set of transducers can be bonded outside the matching layer in Step 5 to form a complete sound lens transducer.

[0019] As a preferred solution of the process preparation method of a sound lens in the image sonar described in the present invention, wherein: the machining assembly includes:

[0020] A bracket;

[0021] A clamping assembly for fixing the sound-transmitting plastic, and clamping assemblies are installed on both sides of the bottom end of the bracket;

[0022] A laser for cutting the sound-transmitting plastic;

[0023] A moving component for driving a laser to move in multiple directions, and the moving component is installed at the top of the bracket.

[0024] As a preferred solution of a process preparation method of a sound lens in the image sonar of the present invention, wherein: the clamping component includes:

[0025] Two groups of fixing plates, and the fixing plates are fixedly installed at the bottom end of the bracket;

[0026] Electric push rods, and electric push rods are fixedly installed on each group of fixing plates;

[0027] Squeezing plates, the output ends of the electric push rods are fixedly installed with squeezing plates through piston rods, and a sound-transmitting plastic is arranged between the two groups of squeezing plates.

[0028] As a preferred solution of a process preparation method of a sound lens in the image sonar of the present invention, wherein: the moving component includes:

[0029] First side plates, and first side plates are fixedly installed on both sides of the top end of the bracket;

[0030] First screw rods, and the first screw rods are rotationally connected between the two groups of first side plates through bearings;

[0031] First sliders, and the first sliders are threadedly connected to the first screw rods;

[0032] First support plates, and the first support plates are fixedly installed at the bottom of the first sliders;

[0033] First guide rods, and the first guide rods are fixedly installed between the two groups of first side plates, and the inner walls of the first sliders are slidably connected to the first guide rods; [[ID=3l]]

[0034] First servo motors, and the first servo motors are fixedly installed on one group of first side plates, and the output shafts of the first servo motors are fixedly connected to the first screw rods;

[0035] Second side plates, and second side plates are fixedly installed on both sides of the bottom of the first support plates;

[0036] Second screw rods, and the second screw rods are rotationally connected between the two groups of second side plates through bearings;

[0037] Second sliders, and the second sliders are threadedly connected to the second screw rods;

[0038] Second support plates, and the second support plates are fixedly installed at the bottom of the second sliders;

[0039] Second guide rods, and the second guide rods are fixedly installed between the two groups of second side plates, and the inner walls of the second sliders are slidably connected to the second guide rods;

[0040] A second servo motor, which is fixedly installed on a group of second side plates, and the output shaft of the second servo motor is fixedly connected to a second screw.

[0041] As a preferred embodiment of the process preparation method of a sound lens in the image sonar of the present invention, wherein: the moving component further includes:

[0042] A box body, which is fixedly installed on the bottom of the second support plate;

[0043] A cylinder, which is fixedly installed on the inner wall of the box body;

[0044] A lifting plate, the output end of the cylinder is fixedly installed with the lifting plate through a piston rod, and a laser is fixedly installed at the bottom of the lifting plate.

[0045] Compared with the prior art:

[0046] The sound lens group made by the present invention has the characteristics of strong structure and small attenuation, and the design of the lens group ensures the large aperture, wide field of view, and corrected aberration and chromatic aberration of the imaging system, and can achieve good imaging effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic structural diagram of the first step of the present invention;

[0048] Figure 2 It is a schematic structural diagram of the second step of the present invention;

[0049] Figure 3 It is a schematic structural diagram of the third step of the present invention;

[0050] Figure 4 It is a schematic structural diagram of the fourth and fifth steps of the present invention;

[0051] Figure 5 It is a schematic structural diagram of an embodiment of the present invention;

[0052] Figure 6 It is a front view schematic diagram of the machining component of the present invention;

[0053] Figure 7 It is a front view schematic diagram of the moving component of the present invention;

[0054] Figure 8 It is a partial structure bottom view schematic diagram of the moving component of the present invention.

[0055] In the figure: lens skeleton 10, pouring hole 20, sound-refracting material 30, sealing material 40, matching layer 50, transducer 60;

[0056] Bracket 11, fixed plate 21, electric push rod 22, extrusion plate 23, first side plate 41, first screw rod 42, first slider 43, first guide rod 44, first servo motor 45, first support plate 46, second side plate 51, second screw rod 52, second slider 53, second guide rod 54, second servo motor 55, second support plate 56, box body 61, cylinder 62, lifting plate 63, laser 71. Detailed implementation mode

[0057] To make the purpose, technical solution and advantages of the present invention clearer, the following will further describe the implementation mode of the present invention in detail with reference to the drawings.

[0058] The present invention provides a process preparation method for a sound lens in an image sonar. Please refer to Figures 1 - 4 , including the following specific steps:

[0059] Step 1: Form lens curved surfaces on the opposite end faces of two plastics through a machining component (or through injection molding) to obtain a lens skeleton 10;

[0060] Among them, the plastic is a sound-transmitting plastic, which is hard, has excellent sound-transmitting performance, and can be used for large-scale injection molding production, such as polystyrene (PS), polymethylpentene (PMP), etc.;

[0061] According to the lens design, the lens curved surface can be concave, flat or convex, and can be spherical or aspherical. Sound refracts on the lens curved surface to achieve functions such as convergence and divergence;

[0062] Step 2: Open a semi-circular hole connected to the lens curved surface at the top of the lens skeleton 10. After that, bond the two lens skeletons 10 together by bonding. At this time, the two semi-circular holes will form a circular hole, which is the pouring hole 20;

[0063] Step 3: Inject the sound-refracting material 30 between the two lens skeletons 10 through the pouring hole 20;

[0064] Among them, the sound-refracting material 30 refers to a liquid or liquid rubber with a refractive index different from that of the sound-transmitting plastic, small attenuation, and can be formed by pouring, such as castor oil, silicone oil, room temperature vulcanized silicone rubber (RTV), polyurethane (PU), etc. By adjusting the formula and reinforcing materials, the refractive index and acoustic impedance of the poured sound-refracting material can be adjusted within a wide range, so as to realize sound lenses with different performances;

[0065] Step 4: Seal the pouring hole 20 with the sealing material 40. Among them, if the sound-refracting material 30 is liquid rubber, the pouring hole does not need to be sealed;

[0066] Among them, if the sound-refracting material 30 is liquid rubber, the pouring hole 20 does not need to be sealed;

[0067] The sealing material 40 is glue or plastic;

[0068] Step Five: Paste the matching layer 50 on the opposite ends of the two lens skeletons 10 to obtain a lens;

[0069] Among them, in order to reduce the acoustic reflection caused by the impedance mismatch between the acoustic transmission plastic and the external medium, the outermost layer of the acoustic transmission plastic usually needs to be pasted with the matching layer 50, and the thickness and acoustic impedance of the matching layer can be prepared according to the classical design method of the matching layer 50; in addition, a set of transducers 60 can be bonded to the outside of the matching layer 50 to form a complete acoustic lens transducer.

[0070] The method of the present invention has the following characteristics:

[0071] 1. By adjusting the formula and reinforcing materials, the refractive index and acoustic impedance of the sound-reflecting material 30 can be adjusted within a wide range, so as to design acoustic lenses with various requirements;

[0072] 2. The sound-reflecting material 30 encapsulated in the lens skeleton 10 will not volatilize, flow out or deform, ensuring long-term stable use;

[0073] 3. Since the refractive index of the liquid or liquid rubber is usually greater than that of the acoustic transmission plastic, the made acoustic lens has the characteristics of convex lens convergence and concave lens divergence, which is the same as that of the optical lens. Therefore, mature optical lens design methods and classical structural design lens groups can be used;

[0074] 4. By stacking multiple lens skeletons 10 to form multiple cavities and pouring sound-reflecting materials 30 with different compositions, an integrated lens group can be produced very conveniently;

[0075] 5. All the stacked lens skeletons 10 are of the same composition, so they can be firmly bonded together by methods such as solvent, adhesive, ultrasonic welding, etc.;

[0076] 6. Since the lens skeleton 10 can be produced by a mature injection molding process, and the processes such as bonding, pouring, and sealing holes all have mature production processes, the acoustic lens made by this method can be industrially produced at low cost and in large quantities.

[0077] Example:

[0078] Please refer to Figure 5 , including the specific steps as follows:

[0079] Step 1: Use polystyrene (PS) as the sound-transmitting plastic and form the lens frame 10 by injection molding with a mold. Since this sound lens group is composed of 3 lenses, a total of 4 lens frames are required. Among them, the left side of the lens frame 10a is flat and the right side is concave; the left side of the lens frame 10b is flat and the right side is convex; the left side of the lens frame 10c is convex and the right side is concave; the left side of the lens frame 10d is concave and the right side is flat.

[0080] Step 2: Since the sound lenses 70c and 70d are of a glued structure and there is no frame in the middle, it is necessary to use a mold to pre-cast the sound lens 70d in advance and bond the made sound lens to the left side of the lens frame 10d.

[0081] Step 3: Bond all the lens frames together.

[0082] Step 4: Pour all the lenses through the pouring hole 20. The pouring material is silicone rubber, and different refractive indexes are achieved through different ratios and doping.

[0083] Step 5: Use ultrasonic welding to seal the pouring hole 20.

[0084] Step 6: Bond the matching layer 50 to the left side of the lens frame 10a to achieve impedance matching between PS and water.

[0085] Step 7: Bond the matching layer 50 to the right side of the lens frame 10c to achieve impedance matching between PS and the piezoelectric ceramic.

[0086] Step 8: Complete the production of the sound lens group, and then an array of transducers 60 can be bonded to the right side of the right matching layer 50 to form a complete sound lens transducer.

[0087] Please refer to Figures 6 - 8 , the machining assembly includes: a bracket 11, a clamping assembly for fixing the sound-transmitting plastic, a laser 71 for cutting the sound-transmitting plastic, and a moving assembly for driving the laser 71 to move in multiple directions.

[0088] Clamping assemblies are installed on both sides of the bottom end of the bracket 11, and a moving assembly is installed on the top end of the bracket 11.

[0089] The clamping assembly includes: two groups of fixing plates 21, electric push rods 22, and pressing plates 23.

[0090] The fixing plates 21 are fixedly installed on the bottom end of the bracket 11. An electric push rod 22 is fixedly installed on each group of fixing plates 21. The output end of the electric push rod 22 is fixedly installed with a pressing plate 23 through a piston rod, and the sound-transmitting plastic is provided between the two pressing plates 23.

[0091] The moving component includes: the first side plate 41, the first screw rod 42, the first slider 43, the first guide rod 44, the first servo motor 45, the first support plate 46, the second side plate 51, the second screw rod 52, the second slider 53, the second guide rod 54, the second servo motor 55, the second support plate 56, the box body 61, the air cylinder 62, and the lifting plate 63;

[0092] On both sides of the top end of the bracket 11, the first side plates 41 are fixedly installed. The first screw rod 42 is rotatably connected between the two groups of first side plates 41 through bearings. The first slider 43 is threadedly connected to the first screw rod 42. The first support plate 46 is fixedly installed on the bottom of the first slider 43. The first guide rod 44 is fixedly installed between the two groups of first side plates 41, and the inner wall of the first slider 43 is slidably connected to the first guide rod 44. The first servo motor 45 is fixedly installed on one group of first side plates 41, and the output shaft of the first servo motor 45 is fixedly connected to the first screw rod 42. On both sides of the bottom of the first support plate 46, the second side plates 51 are fixedly installed. The second screw rod 52 is rotatably connected between the two groups of second side plates 51 through bearings. The second slider 53 is threadedly connected to the second screw rod 52. The second support plate 56 is fixedly installed on the bottom of the second slider 53. The second guide rod 54 is fixedly installed between the two groups of second side plates 51, and the inner wall of the second slider 53 is slidably connected to the second guide rod 54. The second servo motor 55 is fixedly installed on one group of second side plates 51, and the output shaft of the second servo motor 55 is fixedly connected to the second screw rod 52. The box body 61 is fixedly installed on the bottom of the second support plate 56. The air cylinder 62 is fixedly installed on the inner wall of the box body 61. The output end of the air cylinder 62 is fixedly installed with the lifting plate 63 through a piston rod, and the laser 71 is fixedly installed on the bottom of the lifting plate 63.

[0093] The working principle of the machining component is as follows: Place the sound-transmitting plastic between the two groups of pressing plates 23. At this time, through the electric push rod 22, the pressing plates 23 are moved towards the sound-transmitting plastic until the two groups of pressing plates 23 press and fix the sound-transmitting plastic. After the sound-transmitting plastic is pressed and fixed, through the air cylinder 62, the lifting plate 63 drives the laser 71 to rise and fall until the laser 71 is at an appropriate height. After that, through the first servo motor 45, the first screw rod 42 is rotated. When the first screw rod 42 rotates, it will drive the laser 71 to move left and right under the action of the first slider 43. At this time, through the second servo motor 55, the second screw rod 52 is rotated. When the second screw rod 52 rotates, it will drive the laser 71 to move back and forth under the action of the second slider 53, so as to drive the laser 71 to move in multiple directions, and then a lens curved surface can be cut on the sound-transmitting plastic. Finally, subsequent processing such as polishing can be carried out according to requirements.

[0094] such as Figure 6As shown, when processing the sound-transmitting plastic on the left clamping component, at this time, the processed sound-transmitting plastic on the right clamping component can be removed, and the new sound-transmitting plastic to be processed can be fixed on the right clamping component to enable continuous processing of the sound-transmitting plastic.

[0095] Among them, the effects brought by the machining component are as follows:

[0096] 1. By setting a moving component for driving the laser to move in multiple directions, it is possible to form lens surfaces of various shapes on the sound-transmitting plastic, thereby improving the practicability of the machining component;

[0097] 2. By setting two groups of clamping components for fixing the sound-transmitting plastic, and by setting a moving component for driving the laser to move in multiple directions, it is possible to realize the function of loading and unloading the sound-transmitting plastic on the other group of clamping components when processing the sound-transmitting plastic, thereby improving the processing efficiency of several sound-transmitting plastics to a certain extent.

[0098] Although the present invention has been described above with reference to the embodiments, various improvements can be made to it and components therein can be replaced with equivalents without departing from the scope of the present invention. In particular, as long as there is no structural conflict, the various features in the disclosed embodiments of the present invention can be combined with each other in any way, and the exhaustive description of these combinations is omitted in this specification only for the sake of saving space and resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A process for preparing a sound lens in an image sonar, characterized in that, The specific steps are as follows: Step 1: Use a machining component to form lens surfaces on the opposite end faces of two plastics to obtain a lens skeleton (10); Step 2: Open a semi-circular hole communicating with the lens surface at the top of the lens skeleton (10). Then, bond the two lens skeletons (10) together by bonding. At this time, the two semi-circular holes will form a circular hole, which is the pouring hole (20); Step 3: Inject the sound-refracting material (30) between the two lens skeletons (10) through the pouring hole (20); Step 4: Seal the pouring hole (20) with a sealing material (40); Step 5: Paste a matching layer (50) on the opposite ends of the two lens skeletons (10) to obtain a lens.

2. The process preparation method of a sound lens in an image sonar according to claim 1, characterized in that, The plastic in Step 1 is a sound-transmitting plastic, which is hard, has excellent sound-transmitting performance, and can be used for large-scale injection molding production.

3. The process preparation method of a sound lens in an image sonar according to claim 1, characterized in that, The sound-refracting material (30) refers to a liquid with a refractive index different from that of the sound-transmitting plastic, low attenuation, and can be formed by pouring. By adjusting the formula and reinforcing materials, the refractive index and acoustic impedance of the poured sound-refracting material can be adjusted within a wide range, so as to realize sound lenses with different performances.

4. The process preparation method of a sound lens in an image sonar according to claim 3, characterized in that, In Step 4, if the sound-refracting material (30) is liquid rubber, the pouring hole (20) does not need to be sealed.

5. The process preparation method of a sound lens in an image sonar according to claim 2, characterized in that, The sealing material (40) in Step 4 is glue or plastic.

6. The process preparation method of a sound lens in an image sonar according to claim 1, characterized in that, In Step 5, a set of transducers (60) can be bonded outside the matching layer (50) to form a complete sound lens transducer.

7. The process preparation method of a sound lens in an image sonar according to claim 2, characterized in that, The machining component includes: A bracket (11); A clamping component for fixing the sound-transmitting plastic, and the clamping components are installed on both sides of the bottom end of the bracket (11); A laser (71) for cutting the sound-transmitting plastic; A moving component for driving the laser (71) to move in multiple directions, and the moving component is installed on the top end of the bracket (11).

8. The process preparation method of a sound lens in an image sonar according to claim 7, characterized in that, The clamping component includes: Two groups of fixing plates (21), and the fixing plates (21) are fixedly installed on the bottom end of the bracket (11); Electric push rods (22), and the electric push rods (22) are fixedly installed on each group of fixing plates (21); A pressing plate (23), and the output end of the electric push rod (22) is fixedly installed with the pressing plate (23) through a piston rod, and the sound-transmitting plastic is arranged between the two pressing plates (23).

9. The process preparation method of a sound lens in an image sonar according to claim 7, characterized in that, The moving component includes: First side plates (41), and the first side plates (41) are fixedly installed on both sides of the top end of the bracket (11); A first screw rod (42), and the first screw rod (42) is rotatably connected between the two first side plates (41) through bearings; A first slider (43), and the first slider (43) is threadedly connected to the first screw rod (42); A first support plate (46), and the first support plate (46) is fixedly installed on the bottom of the first slider (43); A first guide rod (44), and the first guide rod (44) is fixedly installed between the two first side plates (41), and the inner wall of the first slider (43) is slidably connected to the first guide rod (44); The first servo motor (45), the first servo motor (45) is fixedly installed on a set of first side plates (41), and the output shaft of the first servo motor (45) is fixedly connected to the first screw rod (42); The second side plates (51), both sides of the bottom of the first support plate (46) are fixedly installed with the second side plates (51); The second screw rod (52), the second screw rod (52) is rotatably connected between the two sets of second side plates (51) through bearings; The second slider (53), the second slider (53) is threadedly connected to the second screw rod (52); The second support plate (56), the second support plate (56) is fixedly installed on the bottom of the second slider (53); The second guide rod (54), the second guide rod (54) is fixedly installed between the two sets of second side plates (51), and the inner wall of the second slider (53) is slidably connected to the second guide rod (54); The second servo motor (55), the second servo motor (55) is fixedly installed on a set of second side plates (51), and the output shaft of the second servo motor (55) is fixedly connected to the second screw rod (52).

10. The process preparation method of a sound lens in an image sonar according to claim 7, characterized in that, The moving assembly further includes: The box body (61), the box body (61) is fixedly installed on the bottom of the second support plate (56); The cylinder (62), the cylinder (62) is fixedly installed on the inner wall of the box body (61); The lifting plate (63), the output end of the cylinder (62) is fixedly installed with the lifting plate (63) through a piston rod, and a laser (71) is fixedly installed on the bottom of the lifting plate (63).

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