Ultrasonic plasticization microinjection molding apparatus for producing microcantilever beams and method of use

Abstract

The application provides an ultrasonic plasticizing micro injection molding equipment for producing a micro cantilever beam and a use method, relates to ultrasonic plasticizing molding, and comprises a movable mold fixing plate, a fixed mold fixing plate, a base plate, a protective sleeve, a mold assembly and an ultrasonic head. The application utilizes the base plate to form a centering part, the outer profile of the centering part and the inner profile of the protective sleeve are both inclined surfaces, the centering part and the protective sleeve are centered by utilizing the principle of inclined surface fitting, the blanking pipeline formed by the protective sleeve is fitted with the injection hole surface of the mold assembly to realize the centering of the protective sleeve and the mold assembly, the centering efficiency in the ultrasonic plasticizing micro injection process is improved, and the centering difficulty is reduced. Meanwhile, the mold core unit is also improved, the mold core base and the micro structure cavity are designed in a split mode, different stiffness micro structures are conveniently generated, and the forming length of the micro cantilever beam is increased by means of two side feeding.

Description

Technical Field

[0001] This invention relates to ultrasonic plasticizing molding, and particularly to an ultrasonic plasticizing micro-injection molding apparatus for producing micro cantilever beams and its method of use. Background Technology

[0002] Ultrasonic plasticizing micro-injection molding technology utilizes ultrasonic vibration to hammer and melt the polymer, then directly injects the melt into the mold cavity using an ultrasonic tool head or injection plunger, thereby achieving the injection molding of micro-sized, high-precision parts. During the alignment process, the ultrasonic plasticizing micro-injection platform is first in the open mold position, and the upper fixed plate and moving mold fixed plate are installed. At this time, the protective sleeve on the upper fixed plate is in an adjustable position. Then, the ultrasonic tool head descends and extends into the protective sleeve until the lower end of the ultrasonic tool head's amplitude transformer is flush with the lower end face of the protective sleeve. The position of the protective sleeve is then manually adjusted until it is concentric with the ultrasonic tool head, and the position of the protective sleeve is fixed, completing the alignment. After alignment, the ultrasonic tool head is raised, and the feed tube is inserted through the protective sleeve into the plasticizing cylinder, adding polymer particles into the plasticizing hole, ready for plasticizing and molding.

[0003] Achieving proper alignment between the mold and the ultrasonic tool head during ultrasonic plasticizing micro-injection molding has always been a challenge. When the ultrasonic tool head and the protective sleeve cannot be aligned, the gap on one side exceeds the design gap, leading to severe overflow and reduced filling capacity. This is especially true when manufacturing high aspect ratio microstructures such as micro cantilever beams, where the filling difficulty is further increased. Furthermore, the amplitude of the ultrasonic tool head's amplitude transformer, amplified by the transformer, makes it more prone to colliding with the protective sleeve and damaging the amplitude transformer.

[0004] To mold micro cantilever beams with different stiffnesses, the mold core needs to be replaced frequently. Conventional micro cantilever beam mold cores are one-piece (the matrix and microstructure are on the same part), making replacement and adjustment cumbersome and complicated. At the same time, due to the limitation of injection pressure, the length of the molded micro cantilever beam is limited. In addition, when the micro cantilever beam is demolded, uneven stress can easily lead to deformation or even breakage of the micro cantilever beam.

[0005] Based on the aforementioned existing problems, this application provides a rapid centering structure for ultrasonic plasticizing micro-injection molding technology, and also provides a more convenient mold core unit. Summary of the Invention

[0006] This invention provides an ultrasonic plasticizing micro-injection molding device and its method for producing micro cantilever beams. The purpose is to improve centering efficiency and accuracy, and solve the problems of difficult centering and large centering errors in the prior art. At the same time, this application provides a mold core unit that facilitates demolding, which solves the problem that micro cantilever beams are prone to deformation during demolding.

[0007] To achieve the above objectives, embodiments of the present invention provide an ultrasonic plasticizing micro-injection molding apparatus for producing micro cantilever beams, comprising:

[0008] A moving mold fixing plate and a fixed mold fixing plate, wherein the moving mold fixing plate is disposed above the fixed mold fixing plate and the moving mold fixing plate is provided with a central through hole;

[0009] A substrate is disposed on the moving mold fixing plate, and the middle part of the substrate protrudes downward to form a centering part with an outer contour of frustum;

[0010] A protective sleeve is fitted onto the lower end of the centering part, and the inner contour of the protective sleeve fits against the outer contour surface of the centering part. The lower end of the protective sleeve forms a discharge channel.

[0011] A mold assembly includes an upper heating plate and a lower heating plate, with an accommodating space between the upper and lower heating plates to accommodate a mold core unit. The mold core unit includes a mold core base, with a melting groove formed on the upper surface of the mold core base. A square block protruding towards the horizontal center of the melting groove is provided on the inner side wall of the melting groove. A mold core is provided on the square block, with the lower surface of the mold core fitting against the upper surface of the square block. The lower surface of the mold core is provided with a microstructure cavity, the length of which is greater than the length of the square block, and the centerline of the length of the microstructure cavity coincides with the centerline of the length of the square block.

[0012] The mold assembly also includes an injection hole that passes through the upper heating plate and the mold core base. A plasticizing cylinder is provided on the lower heating plate. The plasticizing cylinder and the injection hole are connected at the mold core base. The inner wall of the injection hole fits against the outer contour surface of the material discharge pipe. The plasticizing cylinder is also connected to the melting tank.

[0013] An ultrasonic head is positioned above the substrate, and the amplitude transformer of the ultrasonic head passes sequentially through the centering section, the feeding pipe, the protective sleeve, and the injection hole before completing plasticization at the plasticizing cylinder. The axis of the ultrasonic head coincides with the axis of the centering section, the feeding pipe, the protective sleeve, the injection hole, and the plasticizing cylinder.

[0014] Preferably, the diameter of the upper end of the center section is greater than the diameter of the bottom end, and the inner contour of the protective sleeve includes a first protective inclined surface and a second protective inclined surface. The first protective inclined surface fits into the outer contour surface of the center section, and the second protective inclined surface connects the first protective inclined surface and the discharge pipe.

[0015] Preferably, the upper end of the protective sleeve is folded outward to form a folded edge, and the folded edge is located inside the central through hole;

[0016] The mold assembly also includes an upper fixing plate, which has a fixing plate through hole. The lower end of the protective sleeve passes through the fixing plate through hole, and the upper fixing plate is fixed to the lower surface of the moving mold fixing plate.

[0017] Preferably, the angle between the first protective inclined surface and the axis of the protective sleeve is smaller than the angle between the second protective inclined surface and the axis of the protective sleeve.

[0018] Preferably, the inner wall of the middle section is an inclined surface;

[0019] The injection hole located at the mold core base has a guide surface, the upper edge of the guide surface is smoothly connected to the material discharge pipe, and the lower edge of the guide surface is connected to the plasticizing cylinder.

[0020] Preferably, the lower end of the middle portion is spaced apart from the connection point of the first and second protective inclined surfaces.

[0021] Preferably, the mold assembly further includes a lower fixing plate, on which two square irons for supporting the mold assembly are provided, and an ejection assembly is provided between the two square irons for ejecting the mold core unit out of the melting tank.

[0022] Preferably, the substrate is provided with an ultrasonic bracket for mounting an ultrasonic head. The ultrasonic bracket includes an ultrasonic top plate and an ultrasonic moving plate. The ultrasonic top plate is disposed above the ultrasonic moving plate. The ultrasonic bracket also includes a lead screw and a guide rod. One end of the lead screw and the guide rod is disposed on the substrate, and the other end of the lead screw and the guide rod is disposed on the ultrasonic top plate. The lead screw is screwed to the ultrasonic moving plate, and the guide rod is slidably connected to the ultrasonic moving plate. The ultrasonic moving plate moves up and down under the drive of the lead screw.

[0023] The ultrasonic head is mounted on the ultrasonic moving plate, and the amplitude transformer of the ultrasonic head is coaxial with the centering part.

[0024] Preferably, the square block has chamfers on both sides along its length, and the chamfers are located below the microcantilever beam to guide the molten raw material from both ends of the microstructure cavity into the microstructure cavity.

[0025] This application also provides a method of using an ultrasonic plasticizing micro-injection molding apparatus for producing micro cantilever beams, comprising:

[0026] S1. Mount the substrate onto the moving plate, pass it through the central through-hole in the middle, and fix it in place;

[0027] S2. Connect the upper and lower ends of the protective sleeve to the center and injection hole respectively;

[0028] S3. The ultrasonic head is positioned above the substrate, and the amplitude transformer of the ultrasonic head is coaxial with the centering part;

[0029] S4. Feed the material and start the ultrasonic head for plasticizing and micro-injection molding;

[0030] S5. End the plasticizing micro-injection molding, and open the mold core unit and eject the product.

[0031] The above-described solution of the present invention has the following beneficial effects:

[0032] The centering is achieved by using a frustoconical outer contour to fit the centering part with the protective sleeve surface and the material discharge pipe to fit the injection hole surface. This enables rapid centering of the ultrasonic plasticizing equipment and improves centering efficiency. In addition, this application also improves the mold core unit to overcome the defects of easy bending and breakage of the micro cantilever beam during demolding.

[0033] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0034] Figure 1 This is an overall schematic diagram of the present invention;

[0035] Figure 2a This is the first longitudinal sectional view after the ultrasound stent is hidden;

[0036] Figure 2b This is the second longitudinal sectional view after the ultrasound stent is hidden;

[0037] Figure 3 yes Figure 2a An enlarged schematic diagram of the O section;

[0038] Figure 4 yes Figure 2a Enlarged schematic diagram of the middle mold assembly;

[0039] Figure 5 This is a schematic diagram of the lower heating plate and the mold core unit;

[0040] Figure 6 yes Figure 5 Enlarged schematic diagram of part P in the middle;

[0041] Figure 7 This is a perspective view of the core unit;

[0042] Figure 8 This is a diagram showing the chamfer.

[0043] [Explanation of Labels in the Attached Image]

[0044] 1. Moving mold fixing plate;

[0045] 2. Fixed mold fixing plate;

[0046] 3. Substrate; 31. Centering; 311. Bevel;

[0047] 4. Protective sleeve; 41. Feeding pipe; 42. Folded edge; 43. First protective bevel; 44. Second protective bevel;

[0048] 5. Mold components; 51. Upper heating plate; 52. Lower heating plate; 53. Mold core unit; 531. Mold core base; 5311. Melting groove; 5312. Square block; 5312a. Chamfer; 5313. Notch; 532. Mold core; 5321. Microstructure cavity; 54. Injection hole; 541. Guide surface; 55. Plasticizing cylinder; 56. Upper fixing plate; 57. Lower fixing plate; 58. Square iron; 59. Ejector assembly;

[0049] 6. Ultrasonic head; 61. Ultrasonic top plate; 62. Ultrasonic moving plate; 63. Lead screw; 64. Guide rod. Detailed Implementation

[0050] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0051] like Figure 1-7 As shown, an embodiment of the present invention provides an ultrasonic plasticizing micro-injection molding device for producing micro-cantilever beams, including a moving mold fixing plate 1 and a fixed mold fixing plate 2, wherein the moving mold fixing plate 1 is disposed above the fixed mold fixing plate 2, and the moving mold fixing plate 1 can be moved toward the fixed mold fixing plate 2 by existing equipment (not shown in the figure). A central through hole is provided on the moving mold fixing plate 1. A base plate 3 is provided on the upper surface of the moving mold fixing plate 1, and the center of the base plate 3 protrudes downward to form a centering portion 31 with an outer contour of frustum. A protective sleeve 4 is disposed below the centering portion 31. The protective sleeve 4 has an inner contour, and the inner contour of the protective sleeve 4 fits against the outer contour of the centering portion 31, so that the protective sleeve 4 can be fitted below the centering portion 31. Since the inner contour of the protective sleeve 4 and the outer contour of the centering portion 31 are both formed by rotating inclined surfaces around an axis, the protective sleeve 4 and the centering portion 31 can be automatically aligned when the protective sleeve 4 is fitted below the centering portion 31.

[0052] Reference Figure 2a , 2b 4, Figure 2a and Figure 2bThis is a schematic diagram of two different longitudinal sections, with a right angle between them. As shown, this application also includes a mold assembly 5, which includes an upper heating plate 51 and a lower heating plate 52. A receiving space is formed between the upper heating plate 51 and the lower heating plate 52, embedded in the lower heating plate 52. A mold core unit 53 is provided within this receiving space. The aforementioned mold core unit 53 includes a mold core base 531, which is disposed within the receiving space. A melting groove 5311 is formed on the upper surface of the mold core base 531. A square block 5312 is provided on the inner wall of the side of the melting groove 5311, protruding from the inner wall of the melting groove 5311 towards the horizontal center of the melting groove 5311. A mold core 532 is provided on the square block 5312. The lower surface of the mold core 532 is attached to the upper surface of the square block 5312. A microstructure cavity 5321 is provided on the lower surface of the mold core 532, which is a semi-enclosed structure. Figure 7 As shown, when the mold core 532 is attached to the square block 5312, the central area of ​​the microstructure cavity 5321 forms a closed injection space for molding the raw material. The length A of the microstructure cavity 5321 is greater than the length a of the square block 5312, and the center line of the length of the microstructure cavity 5321 coincides with the center line of the length of the square block 5312.

[0053] Preferably, the accommodating space is formed on the upper surface of the lower heating plate 52, the mold core base 531 is disposed in the accommodating space and connected to the fixing tube of the lower heating plate 52, and the mold core 532 is disposed on the lower surface of the upper heating plate 51. When the lower heating plate 52 and the upper heating plate 51 are vertically attached, the mold core 532 is pressed together with the mold core base 531 in the accommodating space.

[0054] Preferably, refer to Figure 8 The square block 5312 has chamfers 5312a on both sides along the length a. The length of the chamfers 5312a is greater than the length of the microstructure cavity 5321 or the total length of multiple microstructure cavities 5321. During injection molding, the molten material flows conveniently into the microstructure cavity 5321 under the guidance of the chamfers 5312a.

[0055] Because the length of the microstructure cavity 5321 is greater than the length of the square block 5312 and their centerlines coincide, when the mold core 532 is attached to the square block 5312, the two ends of the microstructure cavity 5321 extend out of the square block 5312. At this time, the raw material in the melting tank 5311 enters the microstructure cavity 5321 from both ends, and is plasticized and formed into a microcantilever beam within the microstructure cavity 5321. At the same time, a polymer matrix is ​​formed within the melting tank 5311. When the mold is opened, the mold core 532 is lifted upwards and removed. The microcantilever beam is subjected to an upward tensile force, but because the two ends of the microcantilever beam are fixed to the polymer matrix, it will not warp or break.

[0056] In this application, the distance by which the square block 5312 protrudes towards the horizontal center of the molten pool 5311 is determined by the microstructure cavity 5321. In this embodiment, the microstructure cavity 5321 is linear, and the four microstructure cavities 5321 are arranged in parallel. The distance of the protrusion of the square block 5312 needs to ensure that all four microstructure cavities 5321 can be shielded by the square block 5312.

[0057] Furthermore, the mold assembly 5 also includes an injection hole 54, which passes through the same position of the upper heating plate 51 and the mold core base 531. That is, the injection hole 54 located on the upper heating plate 51 and the injection hole 54 located on the mold core base 531 are coaxial. The lower heating plate 52 is provided with a plasticizing cylinder 55, which is connected to the injection hole 54 at the mold core base 531. The inner wall of the injection hole 54 located on the upper heating plate 51 is in contact with the outer contour surface of the material discharge pipe 41. The plasticizing cylinder 55 is connected to the melting tank 5311.

[0058] In this embodiment, after the material feeding pipe 41 is inserted into the injection hole 54 of the upper heating plate 51, it is vertically spaced a distance from the plasticizing cylinder 55 located on the mold core base 531 and the lower heating plate 52. At the same time, a notch 5313 is provided on the melting tank 5311, and the melting tank 5311 and the plasticizing cylinder 55 are connected through the notch 5313.

[0059] The ultrasonic plasticizing micro-injection molding equipment for producing micro cantilever beams also includes an ultrasonic head 6, which is positioned above the substrate 3 and can be raised and lowered vertically. The amplitude rod of the ultrasonic head 6 passes through the centering part 31, the feeding pipe 41, the protective sleeve 4, and the injection hole 54 in sequence, and completes plasticizing at the upper end of the plasticizing cylinder 55. The amplitude rod coincides with the axis of the centering part 31, the feeding pipe 41, the protective sleeve 4, the injection hole 54, and the plasticizing cylinder 55.

[0060] A plunger is installed inside the plasticizing cylinder 55.

[0061] In this application, the centering of the centering part 31 and the protective sleeve 4 is achieved by using an inclined surface, which improves the centering efficiency and accuracy. The protective sleeve 4 and the mold are aligned by surface bonding. The alignment of the two positions is convenient and simple compared to conventional centering methods.

[0062] Before and after injection molding, the mold core unit 53 needs to be replaced frequently, and the position of the mold assembly 5 will move. Therefore, the alignment of the mold assembly 5 with the protective sleeve 4 and the centering part 31 needs to be adjusted frequently. However, the relative position of the ultrasonic head 6 and the centering part 31 is fixed. Replacing the mold core unit 53 will not affect the alignment result of the ultrasonic head 6 and the centering part 31. Therefore, the ultrasonic head 6 and the centering part 31 can be adjusted during the first injection molding. In subsequent injection molding processes, improving the alignment efficiency of the mold assembly 5 with the protective sleeve 4 and the centering part 31 can achieve the overall alignment efficiency.

[0063] Meanwhile, the core unit 53 provided in this application can feed material from both ends of the microstructure cavity 5321, and after molding, both ends can be demolded simultaneously when the core 532 is removed, ensuring the integrity of the microcantilever beam. The core unit 53 can also increase the filling capacity of the melt in the microstructure cavity 5321, producing a longer microcantilever beam under the same plunger pressure.

[0064] In addition, the core unit 53 includes a split core base 531 and a core 532. By replacing different cores 532, micro cantilever beams with different stiffness can be made.

[0065] In some embodiments of this application, the upper diameter of the centering portion 31 is larger than the lower diameter, making the centering portion 31 an inverted frustum shape. The inner contour of the protective sleeve 4 includes a first protective inclined surface 43 and a second protective inclined surface 44, wherein the first protective inclined surface 43 fits against the outer contour surface of the centering portion 31, and the fit between the first protective inclined surface 43 and the outer contour of the centering portion 31 serves to center the material, while the second protective inclined surface 44 connects the first protective inclined surface 43 and the discharge pipe 41, guiding the raw material from the second protective inclined surface 44 into the discharge pipe 41 during discharge.

[0066] Preferably, the protective sleeve 4 and the feeding pipe 41 can be integrally formed, or they can be manufactured separately and then assembled.

[0067] In some embodiments of this application, the mold assembly 5 further includes an upper fixing plate 56, which has a fixing plate through hole and is used to connect the upper heating plate 51 and the moving mold fixing plate 1.

[0068] The upper end of the aforementioned protective sleeve 4 is bent outward to form a folded edge 42. The diameter of the folded edge 42 is smaller than that of the central through hole but larger than that of the through hole in the fixing plate. The protective sleeve 4 can be attached to the upper fixing plate 56 through the folded edge 42. At the same time, the folded edge 42 can be hidden in the central through hole to shorten the length of the amplitude transformer and reduce the swing amplitude at the bottom of the amplitude transformer.

[0069] In some embodiments of this application, the angle between the first protective inclined surface 43 and the axis of the protective sleeve 4 is smaller than the angle between the second protective inclined surface 44 and the axis of the protective sleeve 4. By limiting the angle between the first protective inclined surface 43 and the second protective inclined surface 44, the overall height of the protective sleeve 4 can be shortened, and the length of the amplitude transformer can also be shortened.

[0070] Of course, the schemes of the first protective slope 43 and the second protective slope 44 can be used simultaneously with the scheme of limiting the flange diameter, which can more significantly shorten the length of the amplitude rod.

[0071] Furthermore, the inner wall of the middle part 31 is a slope 311, and the injection hole 54 located at the core body 531 is formed with an inclined guide surface 541. The upper edge of the guide surface 541 is smoothly connected to the inner wall of the lower pipe, and the lower edge of the guide surface 541 is connected to the plasticizing cylinder 55.

[0072] When material needs to be fed into the plasticizing cylinder 55, simply feed the material into the centering section 31. The material travels along the inner wall of the centering section 31, the second protective slope 44, and the discharge pipe 41 to the guide surface 541. Guided by the guide surface 541, the material melts at the top of the plasticizing cylinder 55 under the action of the amplitude transformer. The guide surface 541 prevents material from accumulating in the discharge pipe 41 and the injection hole 54 located on the mold core base 531, thus avoiding affecting the melting effect.

[0073] Preferably, the lower end of the middle portion 31 is vertically spaced by a distance B at the connection point with the first protective slope 43 and the second protective slope 44. This distance B provides room for movement between the middle portion 31 and the protective sleeve 4, offering installation redundancy.

[0074] In some embodiments of this application, the mold assembly 5 further includes a lower fixing plate 57, on which two square iron blocks 58 are disposed for supporting the mold assembly 5. An ejection assembly 59 is disposed between the two square iron blocks 58, and the ejection assembly 59 is used to eject the product from the melting tank 5311. In this embodiment, the ejection assembly 59 and the ejection principle adopt the existing mold method. The product refers to the polymer matrix formed in the melting tank 5311 and the micro cantilever beam formed in the microstructure cavity 5321, with both ends of the micro cantilever beam integrally formed with the polymer matrix at both ends of the square block.

[0075] In some embodiments of this application, an ultrasonic support for mounting an ultrasonic head 6 is provided on the substrate 3. The ultrasonic support includes an ultrasonic top plate 61 and an ultrasonic moving plate 62. The ultrasonic top plate 61 is positioned above the ultrasonic moving plate 62. The ultrasonic support also includes several lead screws 63 and guide rods 64. One end of the lead screws and guide rods 64 is mounted on the substrate 3, and the other end is mounted on the ultrasonic top plate 61. The guide rods 64 are slidably connected to the ultrasonic moving plate 62, and the lead screws are screwed to the ultrasonic sliding plate. When the lead screws rotate, the ultrasonic moving plate 62 moves up and down to the left and right of the lead screws. The ultrasonic head 6 is mounted on the ultrasonic moving plate 62, and the amplitude transformer of the ultrasonic head 6 is coaxial with the centering part 31.

[0076] In this embodiment, the ultrasonic support is also equipped with a power module, which includes a motor, a reducer, and guide wheels. The motor is mounted on the ultrasonic top plate 61, and the motor's output end is equipped with a reducer. One guide wheel is mounted on the reducer, and the other guide wheels are mounted on lead screws 63. The guide wheels on the reducer and the guide wheels on the lead screws 63 are connected by belt drive. When the motor outputs power, each guide wheel rotates, driving several lead screws 63 to rotate synchronously, so that the ultrasonic moving plate 62 can be raised and lowered stably.

[0077] Preferably, an idler wheel is also provided on the ultrasonic top plate 61. The idler wheel and the guide wheel are also connected by a belt drive. The idler wheel is used to tension the belt and prevent the belt from slipping.

[0078] This application also provides a method of using an ultrasonic plasticizing micro-injection molding apparatus for producing micro-cantilever beams, comprising the following steps:

[0079] Step 1: Mount the substrate 3 on the moving mold fixing plate 1, and pass the centering part 31 through the central through hole, keeping the axis of the centering part 31 collinear with the axis of the central through hole;

[0080] Step 2: Place the mold assembly 5 on the fixed mold fixing plate 2, and at the same time, connect the upper end of the protective sleeve 4 to the centering part 31 and insert the material discharge pipe 41 into the injection hole 54 to complete the centering of the protective sleeve 4 and the mold assembly 5.

[0081] Then fix the positions of the mold assembly 5 and the fixed mold fixing plate 2, and the upper fixing plate 56 and the moving mold fixing plate 1 to ensure that the mold assembly 5 and the protective sleeve 4 are aligned and fixed.

[0082] Step 3: Place the ultrasonic head 6 above the substrate 3, and make the amplitude transformer of the ultrasonic head 6 coaxial with the centering part 31.

[0083] In step three, an ultrasonic support is used to support the ultrasonic head 6, ensuring that the amplitude transformer and the centering part 31 are coaxial, while enabling the ultrasonic head 6 to have a lifting function.

[0084] Step 4: Before starting the ultrasonic head 6, the plasticizing cylinder 55 is blocked with a plunger, and material is fed from above the middle part 31. After feeding, the ultrasonic head 6 is driven down to a position flush with the bottom of the feeding pipe 41. The ultrasonic head 6 then operates to plasticize and micro-inject into the product.

[0085] Step 5: End the plasticizing micro-injection molding, open the mold core unit, and eject the product.

[0086] Specifically, after plasticizing and molding, the ultrasonic head 6 is closed, and the ultrasonic head 6 and the moving mold fixing plate 1 are raised sequentially. When the moving mold fixing plate 1 rises, the mold core 532, which is fixedly connected to the moving mold fixing plate 1, rises along with the moving mold fixing plate 1. The molded microcantilever beam detaches from the microstructure cavity 5321 of the mold core 532. Since both ends of the microcantilever beam are connected to the polymer matrix, the warping and breakage of the microcantilever beam can be effectively avoided under the action of the polymer matrix. After the microcantilever beam is completely detached from the microstructure cavity 5321, the ejection assembly 59 is used to eject the product from the melt tank 5311. When the product is ejected from the melt tank 5311, the microcantilever beam detaches from the upper surface of the square block 5312. After the product is detached, it is cut off from the middle, so that one end of the microcantilever beam is a free end and the other end is a fixed end fixed to the polymer matrix.

[0087] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An ultrasonic plasticizing micro-injection molding apparatus for producing micro-cantilever beams, characterized in that, include: A moving mold fixing plate and a fixed mold fixing plate, wherein the moving mold fixing plate is disposed above the fixed mold fixing plate and the moving mold fixing plate is provided with a central through hole; A substrate is disposed on the moving mold fixing plate, and the middle part of the substrate protrudes downward to form a centering part with an outer contour of frustum; A protective sleeve is fitted onto the lower end of the centering part, and the inner contour of the protective sleeve fits against the outer contour surface of the centering part. The lower end of the protective sleeve forms a discharge channel. A mold assembly includes an upper heating plate and a lower heating plate. A mold core unit is disposed between the upper heating plate and the lower heating plate. The mold core unit includes a mold core base. A melting groove is formed on the upper surface of the mold core base. A square block protruding towards the horizontal center of the melting groove is provided on the inner side wall of the melting groove. A mold core is disposed on the square block. The lower surface of the mold core is in contact with the upper surface of the square block. A microstructure cavity is provided on the lower surface of the mold core. The length of the microstructure cavity is greater than the length of the square block, and the center line of the length of the microstructure cavity coincides with the center line of the length of the square block. The mold assembly also includes an injection hole that passes through the upper heating plate and the mold core base. A plasticizing cylinder is provided on the lower heating plate. The plasticizing cylinder and the injection hole are connected at the mold core base. The inner wall of the injection hole fits against the outer contour surface of the material discharge pipe. The plasticizing cylinder is also connected to the melting tank. An ultrasonic head is positioned above the substrate, and the amplitude transformer of the ultrasonic head passes sequentially through the centering section, the feeding pipe, the protective sleeve, and the injection hole before completing plasticization at the plasticizing cylinder. The axis of the ultrasonic head coincides with the axis of the centering section, the feeding pipe, the protective sleeve, the injection hole, and the plasticizing cylinder.

2. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 1, characterized in that: The diameter of the upper end of the center section is larger than the diameter of the bottom end, and the inner contour of the protective sleeve includes a first protective inclined surface and a second protective inclined surface. The first protective inclined surface fits into the outer contour surface of the center section, and the second protective inclined surface connects the first protective inclined surface and the discharge pipe.

3. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 2, characterized in that: The upper end of the protective sleeve is folded outward to form a folded edge, and the folded edge is located inside the central through hole; The mold assembly also includes an upper fixing plate, which has a fixing plate through hole. The lower end of the protective sleeve passes through the fixing plate through hole, and the upper fixing plate is fixed to the lower surface of the moving mold fixing plate.

4. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 2, characterized in that: The angle between the first protective inclined plane and the axis of the protective sleeve is smaller than the angle between the second protective inclined plane and the axis of the protective sleeve.

5. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 2, characterized in that: The inner wall of the middle section is a slope; The injection hole located at the mold core base has a guide surface, the upper edge of the guide surface is smoothly connected to the material discharge pipe, and the lower edge of the guide surface is connected to the plasticizing cylinder.

6. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 2, characterized in that: The lower end of the middle section is spaced apart from the connection point of the first and second protective slopes.

7. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 1, characterized in that: The mold assembly also includes a lower fixing plate, on which two square irons for supporting the mold assembly are provided, and an ejection assembly is provided between the two square irons for ejecting the mold core unit out of the melting tank.

8. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 1, characterized in that: An ultrasonic bracket for mounting an ultrasonic head is provided on the substrate. The ultrasonic bracket includes an ultrasonic top plate and an ultrasonic moving plate. The ultrasonic top plate is disposed above the ultrasonic moving plate. The ultrasonic bracket also includes a lead screw and a guide rod. One end of the lead screw and the guide rod is disposed on the substrate, and the other end of the lead screw and the guide rod is disposed on the ultrasonic top plate. The lead screw is screwed to the ultrasonic moving plate, and the guide rod is slidably connected to the ultrasonic moving plate. The ultrasonic moving plate moves up and down under the drive of the lead screw. The ultrasonic head is mounted on the ultrasonic moving plate, and the amplitude transformer of the ultrasonic head is coaxial with the centering part.

9. The ultrasonic plasticizing micro-injection molding equipment for producing micro-cantilever beams according to claim 1, characterized in that: The square block has chamfers on both sides along its length. The chamfers are located below the microcantilever beam to guide the molten raw material from both ends of the microstructure cavity into the microstructure cavity.

10. A method of using an ultrasonic plasticizing micro-injection molding apparatus for producing micro cantilever beams, comprising the ultrasonic plasticizing micro-injection molding apparatus for producing micro cantilever beams as described in any one of claims 1-9, characterized in that, include: S1. Mount the substrate onto the moving mold fixing plate, pass it through the central through hole in the middle and fix it; S2. Connect the upper and lower ends of the protective sleeve to the center and injection hole respectively; S3. The ultrasonic head is positioned above the substrate, and the amplitude transformer of the ultrasonic head is coaxial with the centering part; S4. Feed the material and start the ultrasonic head for plasticizing and micro-injection molding; S5. End the plasticizing micro-injection molding, and open the mold core unit and eject the product.

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