Acoustic window component for ultrasonic probe, ultrasonic probe, and manufacturing methods thereof
The acoustic window with a convex surface and divergent wall portions, made from thermoplastic polymers, addresses issues of acoustic compatibility and contamination, ensuring high signal strength and extended probe lifespan.
Patent Information
- Application Number
- JP2024107653
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2026-01-16
- Estimated Expiration
- 2044-07-03
AI Technical Summary
Acoustic windows in ultrasound probes face challenges such as poor acoustic compatibility with living tissue, signal attenuation, deformation causing refraction, and contamination issues, which affect image accuracy and probe lifespan.
The acoustic window is designed with a convex surface and divergent wall portions, made from thermoplastic polymers like polymethylpentene, and injection molded to ensure uniform thickness and robustness, with a second wall portion extending into the probe case for protection and easy cleaning.
This design maintains high signal strength, reduces refraction, and enhances chemical resistance, improving image accuracy and probe hygiene while extending the lifespan of the ultrasound probe.
Smart Images

Figure 2026007642000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to an ultrasonic probe, and more particularly to an acoustic window component positioned corresponding to a probe case at the end of the ultrasonic probe. [Background technology]
[0002] When performing an ultrasound examination, an operator can freely place an ultrasound probe on a scanning object, orient it in any direction, and perform imaging, thereby obtaining non-destructive / non-invasive ultrasound images.
[0003] When performing such an ultrasound examination, the ultrasound probe transmits an ultrasound signal through a component called an acoustic window. The ultrasound echo signals returning from the internal structure of the scanned object pass through the acoustic window and are received by a transducer located inside the acoustic window, which converts them into an electrical signal.
[0004] Acoustic windows that fulfill this role must overcome various technical challenges. For example, they must ensure that the energy of the received ultrasonic echo signal is sufficiently high relative to the energy of the transmitted ultrasonic signal. If the acoustic window material has poor acoustic compatibility with living tissue (water), causing the acoustic window to reflect a large amount of ultrasonic waves from its surface, or if the energy of the ultrasonic waves is significantly attenuated as they pass through the acoustic window, the requirement for a sufficiently high energy ultrasonic echo signal cannot be met. Furthermore, ultrasonic waves have the property that their propagation speed changes depending on the medium they pass through. The propagation speed through the acoustic window must be uniform and within a specified range.
[0005] On the other hand, when performing abdominal ultrasound echography, for example, the acoustic window may be pressed strongly against the abdominal area being examined, requiring a certain level of strength. Deformation of the acoustic window changes the distance between the transducer and the target organ and can cause refraction in undesired directions at the deformed portion. This reduces the accuracy of the ultrasound image. Increasing the thickness of the acoustic window to enhance its robustness increases the aforementioned signal strength problem, so the requirements for robustness and preventing signal strength reduction due to the acoustic window are contradictory. Selecting a stronger acoustic window material to enhance its robustness is often undesirable from the perspective of preventing signal strength reduction due to the acoustic window.
[0006] Furthermore, for example, when an ultrasound probe is placed between the ribs of a subject to perform an ultrasound echo examination, the shape of the acoustic window may be designed to be thin in the elevation direction and have a smoothly curved surface to reduce pain to the subject.
[0007] Furthermore, ultrasound examinations can cause various types of dirt and contaminants to adhere to the acoustic window of an ultrasound probe, or the propagation of bacteria. To prevent these problems and shorten the lifespan of ultrasound probes, ultrasound probe manufacturers provide users with cleaning, disinfection, and sterilization guides for ultrasound probes (e.g., "GE Healthcare Japan, Modality-Specific Disinfection Guidelines"). Following these cleaning, disinfection, and sterilization guidelines, ultrasound probes are typically scrubbed with a sponge, washed with water, or immersed in a disinfectant solution for several minutes to several hours. In addition, for certain ultrasound probe applications, disinfection and cleaning may be performed by applying steam to the ultrasound probe. For this reason, acoustic windows must be made of materials with excellent chemical and heat resistance and the required rigidity. [Prior art documents] [Patent documents]
[0008] [Patent Document 1] Special Publication No. 2022-536626 [Patent Document 2] Japanese Patent Application Publication No. 2017-012381 Summary of the Invention [Problem to be solved by the invention]
[0009] Therefore, it is desired to provide an acoustic window having excellent properties and shapes, and an ultrasonic probe including the same. [Means for solving the problem]
[0010] In a first aspect of the present disclosure, an acoustic window is provided. The acoustic window is positioned at the end of an ultrasonic probe, corresponding to a probe case. The acoustic window component extends in the azimuth direction and includes a convex surface that contacts an object to be inspected, and first and second wall portions that extend divergently from each other. At least a portion of the first wall portion is disposed along the inner surface of the probe case, and the second wall portion includes an outer surface that is continuous with the convex surface.
[0011] In a second aspect of the present disclosure, there is provided an ultrasonic probe having an acoustic window, the ultrasonic probe including: an acoustic window having the features of the first aspect of the present disclosure; a module including an ultrasonic transducer and an acoustic lens that focuses ultrasonic waves generated from the ultrasonic transducer; a probe case that houses the main body of the ultrasonic probe therein; The acoustic lens has a convex outer surface that corresponds to the concave shape of the back surface of the acoustic window component, and the convex outer surface of the acoustic lens is acoustically coupled to the back surface of the acoustic window component.
[0012] A third aspect of the present disclosure provides an ultrasound diagnostic device, comprising: an ultrasound probe having the features of the second aspect of the present disclosure; an image processing unit that generates an ultrasound image based on ultrasound signals collected by the ultrasound probe; and a display device that displays the ultrasound image.
[0013] In a fourth aspect of the present disclosure, there is provided a method for manufacturing an acoustic window component, the method comprising the steps of providing a mold having an inner surface corresponding to an acoustic window comprising the features of the first aspect of the present disclosure, and injection molding the acoustic window component by injecting a molten thermoplastic polymer into the mold.
[0014] A fifth aspect of the present disclosure provides a method for manufacturing an ultrasonic probe, comprising the steps of: manufacturing an acoustic window component according to the method for manufacturing an acoustic window component having the features of the fourth aspect of the present disclosure; preparing a module including an ultrasonic transducer and an acoustic lens that focuses ultrasonic waves generated from the ultrasonic transducer, the acoustic lens having a convex outer surface corresponding to the concave surface of the back surface of the acoustic window component; and bonding the acoustic lens to the module including the ultrasonic transducer with a first adhesive so that the convex outer surface of the acoustic lens is acoustically coupled to the back surface of the acoustic window component. and bonding the probe case and the first wall portion with a second adhesive so as to accommodate at least a portion of the first wall portion therein, the second adhesive being the same as or different from the first adhesive, the first wall portion and the second wall portion meeting at the acute angle at a branch point, and the branch point being filled with the second adhesive. [Brief explanation of the drawings]
[0015] [Figure 1] 1 is a block diagram showing an example of a schematic configuration of an ultrasound diagnostic system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing the external structure of an ultrasonic probe. [Figure 3] FIG. 2 is a diagram showing the external structure of an ultrasonic probe. [Figure 4] 1 is a cross-sectional view of a probe case cut along a cross section that divides the probe case into two halves, front and back. [Figure 5] FIG. 5 is a diagram showing the structure of a portion including an acoustic window, corresponding to the upper left portion of FIG. 4. [Figure 6]1 is a cross-sectional view of a probe case cut along a plane that divides the probe case into left and right halves. [Figure 7] FIG. 10 is a diagram showing the structure of a comparative example of an acoustic window. [Figure 8] FIG. 7 is a diagram showing the structure of a portion including an acoustic window, corresponding to the upper left portion of FIG. 6. [Figure 9] FIG. 2 is a perspective view of an acoustic window. [Figure 10] FIG. 6 is a six-view diagram of an acoustic window. [Figure 11] FIG. 2 is a cross-sectional view of an acoustic window. [Figure 12] FIG. 2 is an exploded perspective view showing the internal structure of an ultrasonic probe. DETAILED DESCRIPTION OF THE INVENTION
[0016] Hereinafter, embodiments of the present invention will be described. However, the claimed invention is not limited to the embodiments described here. In particular, in this disclosure, a medical ultrasound diagnostic system will be described as an example, but the present invention can be applied to ultrasound inspection systems, ultrasound inspection devices, and ultrasound probes for non-destructive testing of buildings, structures, various mechanical devices, etc.
[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. An ultrasonic diagnostic device 1 shown in Fig. 1 includes an ultrasonic probe 2, a transmit / receive beam former 3, an echo data processing unit 4, a display processing unit 5, a display unit 6, an operation unit 7, a control unit 8, and a storage unit 9. The ultrasonic diagnostic device 1 is configured as a computer.
[0018] The ultrasonic probe 2 is configured to have a plurality of ultrasonic transducers arranged in an array (see FIGS. 4 and 5), and transmits ultrasonic waves to the object to be inspected using these ultrasonic transducers, and receives the resulting echo signals.
[0019] The ultrasonic probe 2 transmits and receives ultrasonic waves to and from the object of examination. The transmit / receive beamformer 3 supplies electrical signals to the ultrasonic probe 2 for transmitting ultrasonic waves from the ultrasonic probe 2 under predetermined scanning conditions based on control signals from the control unit 8. The transmit / receive beamformer 3 also performs signal processing such as A / D conversion and phasing addition processing on the echo signals received by the ultrasonic probe 2, and outputs the echo data after signal processing to the echo data processing unit 4.
[0020] The echo data processor 4 performs the following on the echo data output from the transmit / receive beamformer 3: For example, the echo data processing unit 4 performs B-mode processing such as logarithmic compression and envelope detection to generate B-mode data.
[0021] The display processing unit 5 scan-converts the data input from the echo data processing unit 4 using a scan converter to create ultrasound image data. For example, the display processing unit 5 scan-converts B-mode data to create B-mode image data, and displays an ultrasound image on the display unit 6 based on the ultrasound image data. The ultrasound image is, for example, a B-mode image based on the B-mode image data.
[0022] The display unit 6 is an LCD (Liquid Crystal Display), an organic EL (Electro-Luminescence) display, etc. The operation unit 7 is a device through which a user inputs instructions and information. For example, although not shown, the operation unit 7 includes a keyboard and a pointing device such as a mouse or trackball.
[0023] The control unit 8 is a processor such as a CPU (Central Processing Unit). The control unit 8 reads out a program stored in the storage unit 9 and controls each unit of the ultrasound diagnostic apparatus 1. For example, the control unit 8 reads out a program stored in the storage unit 9 and causes the transmit / receive beamformer 3, the echo data processing unit 4, and the display processing unit 5 to perform the functions according to the read out program.
[0024] The control unit 8 may execute all of the functions of the transmit / receive beamformer 3, all of the functions of the echo data processing unit 4, and all of the functions of the display processing unit 5 by a program, or may execute only some of the functions by a program. When the control unit 8 executes only some of the functions, the remaining functions may be executed by hardware such as a circuit. Note that the functions of the transmit / receive beamformer 3, the echo data processing unit 4, and the display processing unit 5 may be realized by hardware such as a circuit.
[0025] The storage unit 9 is a semiconductor memory such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), a RAM (Random Access Memory), or a ROM (Read Only Memory).
[0026] The ultrasound diagnostic apparatus 1 may have all of an HDD, SSD, RAM, and ROM as the storage unit 9. The storage unit 9 may also be a portable storage medium such as a CD (Compact Disk) or a DVD (Digital Versatile Disk). The programs executed by the control unit 8 are stored in a non-transitory storage medium such as an HDD or a ROM. The programs may also be stored in a portable non-transitory storage medium such as a CD or a DVD.
[0027] 2 and 3 are diagrams showing the external structure of the ultrasound probe 2. FIG. 2 is a front view of the ultrasound probe 2, and FIG. 3 is a right side view of the ultrasound probe 2. In this embodiment, the ultrasound probe 2 is a convex ultrasound probe, but it may be another type of ultrasound probe equipped with an acoustic window having a convex curved surface, such as an ultrasound probe for a bronchial endoscope or a transesophageal ultrasound probe. A convex ultrasound probe has an acoustic window 10 having a convex curved surface and emits ultrasound waves that diffuse radially. A convex ultrasound probe is used for abdominal ultrasound echography, etc.
[0028] As shown in FIGS. 2 and 3 , the acoustic window 10 is joined to the probe case 24 at the tip of the ultrasonic probe 2. In this example, the cable 26 is joined to the probe case 24 at the rear end of the ultrasonic probe 2. In FIG. 2 , the probe 2 is placed so that the bottom surface 233 (see FIG. 3 ) of the probe 2 is in contact with a support surface for the ultrasonic probe 2, such as a desk or table. Therefore, the surface of the probe 2 facing the user is referred to as the top surface 231, and the opposite surface is referred to as the bottom surface 233. However, in some embodiments, the top surface 231 and the bottom surface 233 of the probe 2 may have exactly the same structure. In this case, when the probe 2 is placed upside down, the top surface 231 of the probe 2 may be referred to as the bottom surface 233, and the bottom surface 233 of the probe 2 may be referred to as the top surface 231. Taking this into consideration, the top surface 231 and bottom surface 233 of the probe 2 shown in Figures 2 and 3 can also be seen as the side surfaces of the probe 2, but to make it easier for readers to understand, these two surfaces will be described as the top surface 231 and bottom surface 233 of the probe 2.
[0029] Fig. 4 is a cross-sectional view of the acoustic window 10 and probe case 24 of the ultrasonic probe 2 in some embodiments of the present invention, taken along a cross section 13 (see Fig. 3) that bisects the acoustic window 10 and probe case 24 into front and rear halves, and Fig. 5 is an enlarged view of a portion thereof. Fig. 6 is a cross-sectional view of the acoustic window 10 and probe case 24 of the ultrasonic probe 2 in some embodiments of the present invention, taken along a cross section 11 (see Fig. 2) that bisects the acoustic window 10 and probe case 24 into left and right halves, as shown in Fig. 4, in this embodiment, the acoustic window 10 has an axisymmetric shape with respect to the cross section 11, and as shown in Fig. 6, in this embodiment, the acoustic window 10 has an axisymmetric shape with respect to the cross section 13.
[0030] 4 to 6, the acoustic window 10 in some embodiments of the present invention is arranged to cover a module 28 including a transducer 16 and an acoustic lens 12. The module 28 includes an acoustic matching layer 14, the transducer 16, a reflective layer 18, a flexible substrate 20, and a sound-absorbing material 22. The transducer 16 converts an electrical signal into vibration to generate ultrasound, and vibrates upon receiving an echo signal, converting it into an electrical signal. An acoustic matching layer 14 having a multilayer structure is provided on the transducer 16 in order to acoustically match the acoustic impedance of the transducer 16 with the acoustic impedance of the subject.
[0031] An acoustic lens 12 is provided on the upper surface of the acoustic matching layer 14, which allows ultrasonic waves to be incident on the object to be efficiently focused, and ultrasonic waves are transmitted and received through the acoustic lens 12. In some embodiments of the present invention, protecting the acoustic lens 12 with an acoustic window 10 makes it possible to fabricate the acoustic lens 12 from a material that is soft and easily damaged but has excellent acoustic properties, allowing for the selection of a material suitable for the propagation and refraction of ultrasonic waves. A specific material that can be used for the acoustic lens 12 is silicone rubber, which has an acoustic impedance close to that of water and excellent moldability and releasability.
[0032] The convex surface of the acoustic window 10 that contacts the subject can have a uniform thickness across the azimuth direction. This makes it easier to manufacture the acoustic window 10 to the designed shape and dimensions, reducing the possibility of substandard defective products and improving yield. The acoustic lens 12 has a convex outer surface that corresponds to the concave shape of the back surface of the acoustic window 10, and the convex outer surface of the acoustic lens 12 is acoustically coupled to the back surface of the acoustic window 10. In some embodiments, this acoustic coupling is performed using an adhesive.
[0033] Ultrasonic waves generated from the transducer 16 travel not only forward but also backward. A reflective layer 18 is provided to reflect backward-propagating ultrasonic waves, and sound-absorbing material 22 is provided to absorb backward-propagating ultrasonic waves and suppress unnecessary vibrations. A flexible substrate 20 serves as a lead wire, transmitting electrical signals from electronic components (not shown) to the transducer 16 and transmitting electrical signals from the transducer 16 to the electronic components (not shown). In some embodiments, the acoustic lens 12 is part of a module 28 including a transducer. In some embodiments, the acoustic lens 12 is bonded to the module 28 including an ultrasonic transducer ( FIG. 12 ) with a first adhesive so that the convex outer surface of the acoustic lens 12 is acoustically coupled to the back surface of the acoustic window 10. The convex outer surface of the acoustic lens 12 and the back surface of the acoustic window 10 are also bonded with the first adhesive or another adhesive. The first adhesive and another adhesive may be a silicone-based adhesive or an epoxy resin-based adhesive.
[0034] FIG. 8 is a diagram showing the structure of a portion including the acoustic window 10, corresponding to the upper left portion of FIG. 6. The acoustic window 10 is required to be made of a material with an acoustic impedance close to that of a living body. Furthermore, if the acoustic window 10 is too thin, it will lack strength, and if the acoustic window 10 is subjected to an impact, for example, by dropping the ultrasound probe 2 on the floor, the acoustic window 10 may crack or dent. On the other hand, if the acoustic window 10 is too thick, problems arise such as increased attenuation of ultrasound, reduced sensitivity, and increased refraction due to the difference in sound speed with the living body. For this reason, the acoustic window 10 is required to be formed as thin as possible while maintaining the required robustness.
[0035] The inventors of the present invention provide a wall portion extending from the end of the acoustic window 10 along the inner surface of the probe case 24 to protect components disposed inside the probe case 24 from chemical liquids such as disinfectants, even if such liquids penetrate into the probe case 24. In particular, by sandwiching the transducer-containing module 28 ( FIG. 12 ) between the first wall portion top side 421 and the first wall portion bottom side 422 and covering the module with the probe case 24, the transducer-containing module 28 can be protected from the chemical liquid. To achieve this, in some embodiments, the first wall portion top side 421 and the first wall portion bottom side 422 are formed parallel to each other. Similarly, by sandwiching the transducer-containing module 28 ( FIG. 12 ) between the first wall portion left side side 423 and the first wall portion right side 424 and covering the module with the probe case 24, the transducer-containing module 28 can be protected from the chemical liquid entering from the side of the probe case 24. To enable this, in some embodiments, first wall portion left side 423 and first wall portion right side 424 are formed to be parallel to each other. In some embodiments of the present invention, first wall portion top side 421, first wall portion bottom side 422, first wall portion left side side 423, and first wall portion right side 424 are connected to each other, thereby protecting module 28 including the transducer from chemical liquid entering from all directions. In other embodiments of the present invention, first wall portion top side 421, first wall portion bottom side 422, first wall portion left side side 423, and first wall portion right side 424 are not connected to each other.
[0036] In some other embodiments of the present invention, the acoustic window 10 is formed from a thermoplastic polymer. The acoustic window 10 is preferably formed from a thermoplastic polymer having a density of 0.80 g / cm3 to 0.90 g / cm3 under an environment of 20°C and 1 atmosphere, an acoustic wave velocity of 1600 mm / msec to 2100 mm / msec, and an acoustic energy attenuation of 2.0 dB / mm to 5.0 dB / mm for 7 MHz sound waves. Thermoplastic polymers with these properties often have a mold shrinkage of 1.0% or more. Thermoplastic polymers expand when heated to melt and contract when cooled and hardened in a mold. The mold is made slightly larger than the molded product to account for the expansion and contraction of the plastic. The difference between the dimensions of the molded product and the mold is the mold shrinkage. The mold shrinkage varies depending on the type of material, such as 1.0 to 2.5% for polypropylene and 0.4 to 0.7% for polystyrene.
[0037] In some other embodiments of the present invention, the thermoplastic polymer forming the acoustic window 10 includes polymethylpentene. Polymethylpentene has an acoustic impedance of approximately 1.6 [MRayl], which is close to the acoustic impedance of water, approximately 1.55 [MRayl], which is close to that of a living body, and therefore has good acoustic matching with living bodies (water). However, polymethylpentene has the property of having a sound speed of approximately 2000 [m / sec], which is faster than the sound speed of water, approximately 1550 [m / sec]. It is known that the molding shrinkage of polymethylpentene is 1.5 to 3.0%. In some other embodiments of the present invention, the thermoplastic polymer forming the acoustic window 10, polymethylpentene, is blended with an elastomer selected from polyolefins. The blending ratio of the elastomer to the polymethylpentene is 1% by weight or more and 50% by weight or less. More preferably, the blending ratio of the elastomer is 10% by weight or more and 30% by weight or less. Even more preferably, the blending ratio of the elastomer is approximately 20% by weight. This allows for the production of a robust, wear-resistant acoustic window 10 with excellent acoustic properties and chemical resistance at low cost.
[0038] Constituting the second wall portion 44 of the acoustic window 10 as part of the side wall portion of the ultrasonic probe 2 at the tip of the ultrasonic probe 2 provides several advantages. One of these advantages is that the probe 2 can be provided with a tip that is thin in the elevation direction 237 and has sufficient strength. If the thickness of the probe 2 at the tip in the elevation direction 237 is too large, problems such as increased strain on the subject may occur, for example, when positioning the probe 2 between ribs to image organs behind the ribs. On the other hand, the interior of the probe case 24 must have a certain thickness in the elevation direction to ensure space for the components housed therein. Furthermore, there is a limit to how thin the wall of the integrally molded acoustic window 10 can be. In addition, if the probe case 24 were to extend to the tip portion 247, it would be possible to provide the probe case 24 with a thin portion with a sharp cross-section. However, such a portion of the probe case 24 would be prone to breakage, and designing the probe case 24 in this manner (to provide a thin portion with a sharp cross-section) is not appropriate. If the probe case 24 is extended to the tip portion 247 and the probe case 24 is to have sufficient strength, the cross section of the probe case 24 must be thick all the way to the tip, and as a result, it is not possible to provide a probe 2 whose tip is thin in the elevation direction 237. By having the second wall portion 44 of the acoustic window 10 form part of the side wall portion at the tip portion of the ultrasonic probe, these conflicting issues (thinness in the elevation direction 237 and maintaining strength at the tip portion of the probe 2) can be resolved.
[0039] An advantage of arranging the acoustic window 10 so that it transitions to the probe case 24 without creating a large step is that it makes it easier to maintain the hygienic state of the probe 2. If there is a large step between the acoustic window 10 and the probe case 24, dirt may easily adhere and the dirt may be difficult to remove. Furthermore, by arranging the end of the probe case 24 to support the end of the acoustic window 10, it becomes possible for the end of the probe case 24 to absorb at least a portion of the weight generated on the end of the acoustic window 10.
[0040] Fig. 7 is a diagram showing the structure of an acoustic window 10 as a comparative example having the advantages described above. However, as shown in Fig. 7, the acoustic window 10 of the comparative example differs from the embodiment of the present invention shown in Fig. 6 in that it has an overhang portion 52 that protrudes outward from the first wall portion 42 around the entire periphery of the acoustic window 10. As shown in the figure, it was confirmed that a prototype of the acoustic window 10 having this overhang portion 52 had sink marks 521 and / or voids 523 with a frequency and / or probability that cannot be ignored.
[0041] The acoustic window 10 is formed by injection molding, which can be performed by the following procedure. 1. Material Preparation 2. Clamping 3.Injection 4. Pressure retention 5. Cooling 6.Plasticization 7. Opening the mold 8.Removing the product
[0042] In carrying out the above procedure, a mold having an inner surface corresponding to the acoustic window 10 shown in Figures 9 and 10 is prepared. The acoustic window 10 is injection molded by injecting molten thermoplastic polymer into the prepared mold. The acoustic window 10 is a one-piece molded part. In this example, a polyolefin-based elastomer is blended with polymethylpentene at a blending ratio of 10% by weight to 30% by weight, and then the blend is poured into the mold.
[0043] The inventors of the present invention discovered that the problems of sink marks 521 and voids 523 can be solved by replacing the overhang portion 52 of FIG. 7 with the second wall portion 44 shown in FIG. 8 . The acoustic window 10 of FIG. 8 can be manufactured using the same material and injection molding procedure as the acoustic window 10 of FIG. 7 . However, the overhang portion 52 of FIG. 7 is composed of the first wall portion 42 and the second wall portion 44, which have substantially the same thickness, as shown in FIG. 8 . This structure eliminates any variation in thickness, allowing for uniform cooling and shrinkage of the material. In contrast, the overhang portion 52 of FIG. 7 cools first near the outer surface, causing the material in that area to begin to harden and shrink, while the area farther from the outer surface cools later, causing the material in that area to harden and shrink later. It is believed that this non-uniformity in cooling, hardening, and shrinkage is one of the causes of the sink marks 521 and voids 523.
[0044] In some embodiments of the present invention, the second wall portion 44 is formed around the entire periphery of the acoustic window 10. That is, the second wall portion 44 includes a second wall portion top side 441, a second wall portion bottom side 442, a second wall portion left side 443, and a second wall portion right side 444, which are connected to each other. In some embodiments of the present invention, as shown in FIGS. 5 and 8, the second wall portion 44 extends outward from the first wall portion 42 at an acute angle from the junction 54. A cavity is formed between the first wall portion 42 and the second wall portion 44 of the injection-molded acoustic window 10. In some embodiments, the cavity (preferably including the junction 54) is filled with the first adhesive described above or another adhesive to form an adhesive cavity filler 56. In other embodiments, the cavity is filled with a cavity filler 56 made of the same material as the acoustic window 10. In this case, the cavity filling member 56 is injection molded to have a shape corresponding to the shape of the cavity between the first wall portion 42 and the second wall portion 44, and is inserted between the first wall portion 42 and the second wall portion 44 and fixed by adhesive. The acoustic window 10 includes a central portion with a relatively large radius of curvature, second wall portions 44 disposed on both sides thereof, also with relatively large radii of curvature, and shoulder portions connecting the central portion and the second wall portion 44. The shoulder portions have a relatively small radius of curvature. In some embodiments, the branch point 54 is positioned below the shoulders.
[0045] In some embodiments, first wall portion top side 421 and second wall portion top side 441 are formed to form an angle of 20° to 40°, more preferably 25° to 35°, at branch point 54. The same applies to first wall portion bottom side 422 and second wall portion bottom side 442. In some embodiments, first wall portion left side 423 and second wall portion left side 443 are formed to form an angle of 30° to 60°, more preferably 45° to 55°, at branch point 54. The same applies to first wall portion right side 424 and second wall portion right side 444. In this embodiment, the convex surface 50, the first wall portion top side 421, the first wall portion bottom side 422, the first wall portion left side side 423, the first wall portion right side 424, the second wall portion top side 441, the second wall portion bottom side 442, the second wall portion left side side 443, and the second wall portion right side 444 of the acoustic window 10 all have the same thickness. The thicknesses of the convex surface 50, the first wall portion top side 421, the first wall portion bottom side 422, the first wall portion left side side 423, the first wall portion right side 424, the second wall portion top side 441, the second wall portion bottom side 442, the second wall portion left side side 443, and the second wall portion right side 444 of the acoustic window 10 are preferably 0.1 mm to 1.5 mm, more preferably 0.3 mm to 1.0 mm, and even more preferably 0.5 mm. In some embodiments, the second wall portion 44 (all of the second wall portion top surface side 441, the second wall portion bottom surface side 442, the second wall portion left surface side 443, and the second wall portion right surface side 444) has outer surfaces that are continuous with the convex surface 50. This reduces the burden on the subject.
[0046] 8, the second wall portion upper surface side 441 is bent at a position from the branch point 54 that is 60% to 90%, more preferably 70% to 80%, of the total length of the second wall portion upper surface side 441 to approach the first wall portion upper surface side 421, to be more parallel to the first wall portion upper surface side 421, and to have a smoothly curved outer surface. This allows the tip 445 of the second wall portion to be well supported by the tip 248 of the probe case 24, and makes the adhesive bond between the tip 445 of the second wall portion and the tip 248 of the probe case 24 stronger and less likely to break. 8, the outer surface of the second wall portion top side 441 is offset from the outer surface of the top side portion 241 of the probe case 24. However, the second wall portion top side 441 may be designed so that this offset is almost eliminated and the outer surface of the second wall portion top side 441 is continuous with the outer surface of the top side portion 241 of the probe case 24. Reducing the offset has the advantage that dirt is less likely to adhere to the step and is easier to remove. The second wall portion bottom side 442 can be designed in the same way as the second wall portion top side 441.
[0047] 5, the second wall portion left side 443 is bent at a position from the branch point 54 that is 20% to 60%, more preferably 30% to 50%, of the total length of the second wall portion left side 443 to approach the first wall portion left side 423, to be more parallel to the first wall portion left side 423, and to have a smoothly curved outer surface. This allows the tip 445 of the second wall portion to be well supported by the tip 248 of the probe case 24, and makes the adhesive bond between the tip 445 of the second wall portion and the tip 248 of the probe case 24 stronger and less likely to break. As shown in Fig. 5, the outer surface of the second wall portion left side 443 is offset from the outer surface of the left side portion 245 of the probe case 24. However, the second wall portion left side 443 may be designed so that this offset is almost eliminated and the outer surface of the second wall portion left side 443 is continuous with the outer surface of the left side portion 245 of the probe case 24. Reducing the offset has the advantage that dirt is less likely to adhere to the step and is easier to remove. The second wall portion right side 444 can be designed in the same way as the second wall portion left side 443.
[0048] Next, the shape of the acoustic window 10 will be described with reference to FIGS. 9 to 11. FIG. 9 is a perspective view of the acoustic window 10. The acoustic window 10 may be versatile enough to be attached to different types of ultrasound probes, and may also be sold separately. FIG. 10A is a top view of the acoustic window 10, FIG. 10B is a bottom view of the acoustic window 10, FIG. 10C is a front view of the acoustic window 10, FIG. 10D is a rear view of the acoustic window 10, FIG. 10E is a right side view of the acoustic window 10, and FIG. 10F is a left side view of the acoustic window 10. FIG. 11B is a cross-sectional view of the acoustic window 10 taken along line AA in FIG. 11A. FIG. 11C is a cross-sectional view of the acoustic window 10 taken along line BB in FIG. 11A. In this embodiment, the acoustic window 10 is formed of a translucent material.
[0049] FIG. 12 is an exploded perspective view showing the internal structure of an ultrasonic probe. In this embodiment, a metal inner housing 30 is disposed inside the probe case 24 of the ultrasonic probe 2. The inner housing 30 dissipates heat generated in the module 28, which includes a transducer, and prevents the heat generated in the module 28 from being transferred to the subject. The outer surface of the inner housing 30 has a shape that matches the inner surface of the probe case 24. The inner housing 30 can be manufactured by known techniques such as casting, additive manufacturing, CNC machining, forging, and press working. The top portion 301 and the bottom portion 302 of the inner housing 30 are bonded to each other with an adhesive (a first adhesive or another adhesive). The inner surface of the probe case 24 is attached to the outer surface of the inner housing 30 with an adhesive (a first adhesive or another adhesive). The top portion 241 and the bottom portion 242 of the probe case 24 are also bonded to each other with an adhesive (a first adhesive or another adhesive). The front end of the probe case 24 is glued to the acoustic window 10 and the rear end of the probe case 24 is glued to the cable 26 .
[0050] A chassis 38 is positioned inside the inner housing 30. A plurality of electronic components (not shown) are disposed inside the chassis 38. The chassis 38 can be fixed to the transducer-containing module 28 with screws so that the components fixed thereto do not easily move and do not move from their predetermined positions in the ultrasound probe 2. The chassis 38 can also be fixed to other components, such as the inner housing 30, using various known fixing means. In a specific embodiment of the present invention, the electronic components (not shown) are detachably connected to the cable 26 by a connector (not shown) and are also detachably connected to the transducer-containing module 28 by another connector (not shown). This allows power to be supplied from the cable to the electronic components (not shown) and the module 28. Bidirectional signal transmission is also possible via the cable 26.
[0051] In some embodiments of the present invention, an acoustic lens 12 is attached to the back surface of the acoustic window 10 shown in FIG. 12 . The transducer-containing module 28 and the acoustic lens 12 are also coupled so that they are acoustically connected. Next, the transducer-containing module 28 and the chassis 38 are screwed together, and the electronic components and cables of the transducer-containing module 28 are connected with connectors. Then, the top portion 301 and the bottom portion 302 of the inner housing 30 are joined to each other so as to enclose or sandwich the module 28. Next, the top portion 241 and the bottom portion 242 of the probe case 24 are joined to each other so as to enclose or sandwich these components. A portion of the inner surface of the probe case 24 near the tip has a shape corresponding to the first wall portion. The inner surface of the probe case 24 and the first wall portion are joined with a first adhesive or other adhesive.
[0052] The adhesive used to assemble the ultrasonic probe 2 is preferably an adhesive with excellent chemical resistance and UV resistance, such as a silicone-based adhesive or an epoxy resin-based adhesive. From the perspective of miniaturization, the thickness of the adhesive is preferably 5 mm or less. Furthermore, from the perspective of adhesive strength, the thickness of the adhesive is preferably 0.3 mm or more. More preferably, the adhesive has a thickness of 1 to 4 mm. The adhesives applied to each part may be the same or different.
[0053] The invention is not limited to the present embodiment, and various modifications are possible within the scope of the invention. [Explanation of symbols]
[0054] 1: Ultrasound diagnostic equipment 2: Ultrasonic probe 3: Transmit / receive beamformer 4: Echo data processing section 5: Display processing section 6: Display section 7:Operation unit 8: Control unit 9: Storage part 10: Acoustic window 11, 13: Cross section 12: Acoustic lens 14: Acoustic matching layer 16: Vibrator 18: Reflective layer 20: Flexible board 22: Sound absorbing material 231: Top of the probe 233: Bottom of probe 235: Azimuth direction 237: Elevation direction 24: Probe case 241:Top side part 242: Bottom side part 243: Inner surface of the upper part 244: Inner surface of bottom side 245: Left side part 246: Inside of the left side 247:Tip part 248: Tip 26: Cable 28: Module containing oscillator 30: Inner housing 301:Top side part 302: Bottom side part 38: Chassis 42: First wall section 421: Upper surface of the first wall portion 422: Bottom side of the first wall 423: Left side of the first wall 424: Right side of the first wall 425: Tip of the first wall section 44: Second wall section 441: Upper side of the second wall 442: Bottom side of the second wall 443: Left side of the second wall 444: Right side of the second wall 445: Tip of the second wall section 50: Convex 52: Eaves 521: Sink 523: Void 54: Branching point 56: Cavity filling material
Claims
1. an acoustic window component positioned corresponding to the probe case at the end of the ultrasonic probe, a convex surface extending in the azimuth direction and contacting the inspection object; a first wall portion and a second wall portion extending divergently from each other; Equipped with At least a portion of the first wall portion is disposed along an inner surface of the probe case; The second wall portion has an outer surface that is continuous with the convex surface.
2. The acoustic window component of claim 1 , wherein the first wall portion and the second wall portion diverge at an acute angle at the peripheral edge of the convex surface.
3. The acoustic window assembly of claim 2 , wherein the first wall portion has approximately the same thickness as the second wall portion.
4. The acoustic window part according to claim 1 , wherein the acoustic window part is made of a thermoplastic polymer, and the thermoplastic polymer has a molding shrinkage rate of 1.0% or more.
5. The acoustic window part is formed from an elastomer selected from polymethylpentene, which is a thermoplastic polymer, and polyolefins blended therewith, 2. The acoustic window part according to claim 1, wherein the blending ratio of the elastomer is 1% by weight or more and 50% by weight or less.
6. The acoustic window part according to claim 5 , wherein the blending ratio of the elastomer is 10% by weight or more and 30% by weight or less.
7. the first wall portion includes a front portion extending along a front surface of the ultrasonic probe and a rear portion extending along a rear surface of the ultrasonic probe; The acoustic window component of claim 2 , wherein the front portion of the first wall portion and the back portion of the first wall portion extend parallel to each other and apart in an elevation direction (237).
8. the first wall portion includes a right side surface portion extending along a right side surface of the ultrasonic probe and a left side surface portion extending along a left side surface of the ultrasonic probe; The acoustic window component of claim 7 , wherein the right side portion of the first wall portion and the left side portion of the first wall portion extend parallel to each other and spaced apart in an azimuth direction (235).
9. The acoustic window assembly of claim 2 , wherein the second wall portion comprises a front portion extending along a front surface of the ultrasonic probe and a rear portion extending along a rear surface of the ultrasonic probe.
10. an outer surface of the front portion of the second wall portion and the convex surface of the acoustic window component are connected to each other by a continuous curve in a cross section dividing the ultrasonic probe into left and right halves; The acoustic window component according to claim 9 , wherein the outer surface of the back portion of the second wall portion and the convex surface of the acoustic window component are connected to each other by a continuous curve in the cross section dividing the left and right portions.
11. The acoustic window component of claim 10 , wherein the second wall portion comprises a right side portion extending along a right side surface of the ultrasonic probe and a left side portion extending along a left side surface of the ultrasonic probe.
12. The acoustic window component according to claim 1 , wherein the thickness of the convex surface is constant across the azimuth direction.
13. The acoustic window component according to claim 12, wherein the thickness of the convex surface is 0.1 mm or more.
14. The acoustic window component of claim 1 , wherein the acoustic window component is a single-piece molded component.
15. An ultrasound probe, An acoustic window component according to any one of claims 1 to 14; a module including an ultrasonic transducer and an acoustic lens that focuses ultrasonic waves generated from the ultrasonic transducer; a probe case that houses the main body of the ultrasonic probe; Equipped with the acoustic lens has a convex outer surface that corresponds to the concave shape of the back surface of the acoustic window component; The ultrasound probe, wherein the convex outer surface of the acoustic lens is acoustically coupled to the back surface of the acoustic window component.
16. the first wall portion extends between the probe case and the transducer module; The ultrasonic probe of claim 15 , wherein the second wall portion has an outer surface that is continuous with an outer surface of the front end of the probe case.
17. The ultrasonic probe according to claim 15, wherein the ultrasonic probe is a convex type ultrasonic probe.
18. The ultrasonic probe according to claim 15; an image processing unit that generates an ultrasound image based on the ultrasound signals collected by the ultrasound probe; a display device that displays the ultrasound image; An ultrasound diagnostic device comprising:
19. providing a mold having an inner surface corresponding to the acoustic window component of any one of claims 1 to 14; injection molding the acoustic window component by injecting a molten thermoplastic polymer into the mold; A method for manufacturing an acoustic window component comprising:
20. manufacturing the acoustic window component according to the method of claim 19; providing a module including an ultrasonic transducer and an acoustic lens for focusing ultrasonic waves generated by the ultrasonic transducer, the acoustic lens having a convex outer surface corresponding to a concave rear surface of the acoustic window component; bonding the acoustic lens to the module containing the ultrasound transducer with a first adhesive such that the convex outer surface of the acoustic lens acoustically couples to the back surface of the acoustic window component; bonding the probe case and the first wall portion with a second adhesive so as to house at least a portion of the first wall portion therein; Including, the second adhesive is the same as or different from the first adhesive; the first wall portion and the second wall portion intersect at the acute angle at a bifurcation point; The method for manufacturing an ultrasonic probe, wherein the branch point is filled with the second adhesive.
Citation Information
Patent Citations
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