JP2004066486A - Method and apparatus for manufacturing minute component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for manufacturing a minute component which can easily form an accurate and fine product, can perform reduction in runner loss and size of the apparatus and can decrease an energy consumption to at most 1/10 as large as a prior art. <P>SOLUTION: A material is plasticized, the plasticized material is quantified by applying a hydrostatic pressure to a plasticized material bath of the plasticized material, and the quantified material is heat compression molded. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for manufacturing a fine product represented by a fine optical component or the like.
[0002]
[Prior art]
Conventionally, micro optical parts, for example, micro parts having a size of several millimeters or less, are generally manufactured by injection molding into a mold by plasticizing a material such as resin.
However, such an injection molding method has the following problems.
{Circle around (1)} It is difficult to increase the molding accuracy due to shrinkage and sink marks at the time of molding. For this reason, ultra-fine ones of 1 mm or less could not be accurately molded.
[0003]
(2) In injection molding, since an injection path to the mold cavity is indispensable, a runner is generated, and the runner loss amount reaches about 75% of the material. Moreover, for example, materials used for optical parts cannot be regenerated, resulting in a large amount of industrial waste, which is difficult to process.
[0004]
(3) Injection molding is generally a method in which a material is melted and sealed in a mold cavity at a high pressure. Injection conditions are an injection pressure of 300 to 400 kg · cm ² , a mold clamping force of 20 to 50 t, and a heating of 4 kW. The cooling water is 30 L / min. For this reason, the size of the apparatus is increased, high pressure and high energy are consumed, a large clean room is required, and the overall cost is high.
[0005]
Regarding the molding accuracy of (1), a remelt method has been proposed and put into practical use, but since a preform product was prepared by injection molding, it did not lead to a fundamental solution of runner loss. .
[0006]
[Problems to be solved by the invention]
The present invention has been made to solve the above-described problems, and the object of the present invention is to easily perform high-precision molding of fine products, and to reduce runner loss and reduce the size of the apparatus. It is an object of the present invention to provide a method and an apparatus for manufacturing a fine component that can achieve the reduction in energy consumption and can be reduced to 1/10 or less of the conventional one.
[0007]
In the present invention, “fine product” means a product having a small groove or unevenness on the surface in addition to a case where the dimension is small. Examples thereof include a microlens, a hologram element, a light guide plate, and a diffraction grating optical fiber connector. And various optical functional parts, micromachine parts, bio-related (DNA, etc.) chip parts, and the like.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a method for producing a fine part according to the present invention comprises plasticizing a material, quantifying the plasticized material by applying hydrostatic pressure to a plasticized material bath, and hot compressing the quantified plastic material. It is characterized by.
According to this method, since the quantified plastic material is molded by heat and compressive force, shrinkage and sink can be reduced and accuracy can be improved, and by applying hydrostatic pressure to the plasticized material bath, Since quantification prevents generation of voids, it can be reliably filled into the mold, and molding is performed by heat-compressing the material weighed instead of the injection pressure, so-called runner loss can be reduced, and the molten material Is not sealed at high pressure, so low pressure is required and the cavity is small, so energy consumption can be reduced.
[0009]
The present invention includes a technique of preforming simultaneously with quantification and hot compression molding it. According to this, since the fixed and preformed material is hot compression molded, runner loss can be made almost zero and the molding accuracy can be increased.
[0010]
An apparatus for manufacturing a fine part according to the present invention includes a plasticizing unit that plasticizes a material, a quantifying unit that quantifies the plasticized material, and a compression molding unit that performs hot compression molding of the quantified material. The quantification unit is equipped with a pressure mold in which at least one of them can be stroked by an actuator, and the compression molding unit applies a molding force by closing the cavity, a heater for heating the material in the cavity, and the cavity. And a pair of slide blocks, and the slide blocks are configured to be combined by a wedge action when the mold is clamped.
According to this configuration, a minute part can be manufactured at low cost under energy-saving conditions. Moreover, since the mold clamping is performed by the outer and inner double layers, the molding accuracy is good, and the mold is slid to open and close the mold. The height of the compression molding part is lowered, and a desktop type small device can be obtained.
[0011]
The apparatus according to the present invention includes a pressurizing die having a preform cavity, and one of the slide blocks of the compression molding portion projects into a free space outside the other slide block when the die is opened. Includes what is configured as:
According to this configuration, the quantified material can be easily loaded into the cavity and taken out after molding, and the runner loss can be made almost zero.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
1 to 5 show a first embodiment of a method and an apparatus for manufacturing a fine part according to the present invention. In FIG. 1, 1 is a plasticizing part, 2 is a quantifying part, 3 is a compression molding part, 4 Is a post-processing unit. The plasticizing unit 1, the quantifying unit 2, the compression molding unit 3 and the post-processing unit 4 are arranged in a clean room 5 on the table, and are related to each other by remote operation from the outside.
[0013]
FIG. 8 shows an example of a fine product molded according to the present invention. (A) is a microlens (including an aspherical surface) having a maximum length of several 5 mm or less, (b) is a hologram or diffraction grating, c) is a hologram lens, (d) is an optical fiber connector or light guide plate, and (e) is a micromachine component. The light guide plate and the like range from the size of the display plate of the mobile phone to the size of A5 plate to A4 plate, but the thickness is around 1 to 2 and 3 mm, and there are irregularities and grooves on the surface.
[0014]
The plasticizing section 1 is a means for plasticizing the material for producing the fine product P and supplying it to the downstream quantifying section 2. The plasticizing section 1 is provided with a storage tank 6 for storing the material W and a gate valve 7. And a plasticizing / injecting mechanism 8 connected to each other.
The plasticizing / injecting mechanism 8 has a cylindrical plasticizing chamber 81 in which the raw material W is heated by an external heater 80 to bring it into a plastic state. Connected to the quantification unit 2 by 810. The plasticizing chamber 81 has a pressurizing element 82 for extruding the plasticizing material W1 into the passage 810. The pressurizing element 82 is a piston type in the illustrated one, but may be a screw type instead.
[0015]
As the raw material W, any plasticizable material can be used according to a fine product to be manufactured, such as a synthetic resin alone or a metal, ceramic, glass or the like with a synthetic resin binder added. In any case, the raw material W is charged into the storage tank 6 in the form of pellets or particles. The storage tank 6 includes those equipped with a stirring element.
[0016]
The quantification unit 2 not only functions as a feeder for quantitatively supplying the plasticized material to the compression molding unit 3 in the next process, but also includes a hole in the plasticized material or the compression molding unit 3 in the next process. In this case, the plasticizer is pressurized under hydrostatic pressure.
The quantification unit 2 includes pressure dies 9a and 9b that can be stroked by an actuator (for example, a cylinder) 90. In this example, the quantification unit 2 also serves as a preform unit. Is provided with a cavity 900, and an injection valve 10 is provided in a passage 810 closest to the injection port 91 that leads to the cavity 900. The volume of the cavity 900 is substantially matched with the volume of the cavity of the compression molding unit 3.
[0017]
The cavity 900 has a contour capable of forming an arbitrary shape, for example, a spherical shape, a columnar shape, a hemispherical shape, a semi-columnar shape, and the like. The quantified plasticizing material W2 can be taken out by the separation.
The take-out gate 92 is communicated with the compression molding unit 3 by the conveying means 11. The conveying means 11 is optional, and may be a stationary type, for example, a seesaw type passage, a vacuum suction passage, or a robot arm.
[0018]
The compression molding unit 3 is a means for thermally compressing the quantified plasticized material W2 (which is further preformed in this example) to form a desired shape, and a cavity unit for receiving the quantified material; It has a pair of slide blocks 3b and 3b 'provided with a heater for heating the material in the cavity and a means for closing the cavity and imparting a molding force, and these slide blocks are combined by a wedge action during mold clamping. It is configured to be. In this example, one of the slide blocks protrudes to the side from the other when the mold is opened.
[0019]
Specifically, as shown in FIGS. 2 and 3, the compression molding unit 3 includes a holding block 3a, a pair of slide blocks 3b and 3b ′, and slide block guides 3c and 3c ′.
The holding block 3a has a seat hole 30 having a required depth at the rear end in the axial direction, and a tapered hole 31 that gradually increases in diameter from the bottom wall 300 spaced from the seat hole 30 toward the front end. Is formed.
[0020]
The holding block 3a has a tapered extension 3a ′ formed in the lower half, and a concave groove 310 extending in the radial direction from the front end to the required position is formed in the ceiling area of the tapered hole 31. A groove 310 ′ that extends in the radial direction until reaching a required position is formed in the lower portion of the tapered hole that is 180 degrees symmetrical to the groove 310 and the extension 3a ′. A stopper 311 protrudes from the tip of the concave groove 310 ′. The concave grooves 310 and 310 ′ are parallel to the tapered hole 31 in the axial direction.
[0021]
The slide blocks 3b and 3b 'have a shape that is vertically divided into two along the center line CL so as to form a truncated cone shape when they are combined, and are 180 degrees symmetrical near the outer periphery of the slide blocks 3b and 3b'. The slide block guides 3c and 3c ′ are fitted and fixed at the positions, and the convex portions 32 and 32 ′ of the slide block guides 3c and 3c ′ are slidably fitted into the concave grooves 310 and 310 ′. Yes.
[0022]
Ball screws 3d and 3d 'parallel to the tapered holes extend in the concave grooves 310 and 310' of the holding block 3a. The ball screws 3d and 3d 'are nuts 33 fixed to the slide block guides 3c and 3c'. , 33 ',
The front ends are supported by bearings fixed in the concave grooves 310 and 310 ′, and the rear ends are connected to motors 3 e and 3 e ′ installed in the seat holes 30.
Therefore, the slide block guides 3c and 3c ′ and the slide blocks 3b and 3b ′ integrated with the slide block guides 3c and 3c ′ are moved along the concave grooves 310 and 310 ′ and the tapered hole 31 by driving the motors 3e and 3e ′.
[0023]
The mating surfaces 33 and 33 ′ of the slide blocks 3b and 3b ′ are formed with stepped holes whose backs reach the lower end surfaces of the slide block guides 3c and 3c ′, and the stepped holes have a rectangular frame shape. The holders 3f and 3f 'are embedded and fixed, and cavity blocks 3g and 3g' having mold surfaces 330 and 330 'opened toward the mating surfaces are slidably inserted. The cavity blocks 3g and 3g ′ are formed with stopper surfaces that come into contact with the corners of the holders 3f and 3f ′.
The one or both of the mold surfaces 330, 330 ′ are engraved with irregularities and grooves.
The cavity blocks 3g and 3g 'are embedded with heaters 3h and 3h' and a temperature sensor, respectively, and a refrigerant passage for cooling the molded product is provided. Further, a suction path (not shown) whose tip communicates with the cavity is provided in order to discharge gas generated during molding. The suction path is connected to a suction machine such as a vacuum pump.
[0024]
Clamping servo actuators 3j and 3j ′ are fixed to lower end surfaces of the slide block guides 3c and 3c ′, and output portions of the actuators 3j and 3j ′ are connected to the cavity blocks 3g and 3g ′. It is connected. In this example, a motor is used for the actuators 3j and 3j ′, and a screw shaft that is rotationally driven by this is screwed into a nut fitted in the cavity blocks 3g and 3g ′.
[0025]
As shown in FIG. 1, the compression molding unit 3 is provided with a take-out conveying means 12 for the molded product P. The take-out conveying means 12 is optional, but in this example, it has an adsorption part 12a in the lower part, and consists of an arm tool that can be turned at least by the upper actuator 12b.
[0026]
The post-processing unit 4 is a means for performing cleaning, coating, weighing, and the like, and a packaging unit is disposed downstream thereof.
In the illustrated embodiment, the plasticizing unit 1, the quantifying unit 2, the compression molding unit 3, and the post-processing unit 4 are arranged in a horizontal arrangement, but the whole may be arranged in a vertical arrangement, and this is also included in the present invention.
[0027]
In the first embodiment, the raw material W is charged into the storage tank 6. In forming, if the gate valve 7 is opened, the raw material W is supplied to the plasticizing chamber 81 of the plasticizing / injecting mechanism 8. Then, when the heater 80 is operated, the raw material W is melted and plasticized by heating, and thereafter, the pressurizing element 82 is operated to be injected into the quantification unit 2 via the injection valve 10 and under hydrostatic pressure. Is quantified. Since this injection is not for molding into a product shape, a low pressure of about 100 kg · cm ² is sufficient at most.
[0028]
FIG. 5 shows the state at this time. Since the pressurizing dies 9a and 9b are separated as shown in FIG. 5A, the plasticizing material W1 is injected into the cavity 900 through the injection valve 10. FIG.
When the injection valve 10 is closed and the pressurizing molds 9a and 9b are operated, the end faces of the pressurizing molds 9a and 9b are in contact with each other so that the cavity 900 is closed as shown in FIG. Is measured in the cavity 900, and at the same time, in this embodiment, the quantified plasticized material W2 is preformed into a shape that approximates the molded shape. At least the surface of the quantified plasticizer W2 is solidified.
[0029]
Next, as shown in FIG. 5C, the pressurizing dies 9a and 9b are separated from each other, the cavity 900 is opened by opening the take-out gate 92, and the quantification plasticizing material W2 is transferred from the quantification unit 2 via the unloading means 11. The compression molding unit 3 is loaded.
At this stage, the compression molding portion 3 is in a position where the lower slide block 3b ′ protrudes so as to reach the end of the tapered extension portion 3a ′ in the lower half of the holding block as shown in FIG. The mold surface 330 ′ is at the lower limit position by the block 3g ′ being retracted.
[0030]
The quantified plasticizing material W2 is loaded on the mold surface 330 ′ of the cavity block 3g ′ via the conveying means 11. This loading can be easily performed because the cavity block 3g ′ protrudes into the free space larger than the slide block 3b as the upper die as described above.
[0031]
When the quantified plasticizing material W2 is loaded as described above, the slide blocks 3c and 3c ′ and the slide blocks 3b and 3b ′ integrated with the slide blocks 3c and 3c ′ are driven by the motors 3e and 3e ′. 'And moved along the tapered hole 31 to the right side, that is, the smaller diameter side in the drawing. As a result, the wedge action is exerted, and the mating surfaces 33 and 33 ′ of the slide blocks 3b and 3b ′ are brought into close contact with each other as shown in FIGS.
[0032]
When the actuators 3j and 3j ′ are operated in this state, the pair of slide block guides 3c and 3c ′ are clamped so as to be in close contact with each other, and a cavity having a closed cross section is formed by the mold surfaces 330 and 330 ′. At the same time as the plasticizing material W2 is compressed, it is heated by the heaters 3h and 3h 'to perform hot compression molding. The gas generated at the time of molding is sucked by the suction path.
Because of this, high-precision molding of the contour shape is performed, the unevenness and grooves on the mold surface are accurately transferred, and the material is quantified in advance, so there are few burrs and so-called runner loss. There is little corresponding waste. In addition, the clamping force can be small.
[0033]
When the molding is completed in this way, the actuator 3j ′ is operated to lower the slide block guide 3c ′, and the motors 3e and 3e ′ are operated in the reverse direction. As a result, the slide block 3b ′ protrudes to the position shown in FIG. 2, so that the molded product P is placed at a position suitable for removal.
When the take-out conveying means 12 is lowered, the molded product P is taken out and conveyed to the downstream post-processing unit 4 where necessary processing is performed. The measurement result of the accuracy of the molded product at this time is sent to the controller, and the operation amount of the actuator 90 of the quantification unit 2 is adjusted by the signal from this.
In the first embodiment, the material is quantified, preformed, and molded by the compression molding section 3, so that the first embodiment is suitable for a minute product that requires fineness and precision.
[0034]
FIG. 6 shows a second embodiment of the present invention.
This embodiment is also provided with a plasticizing section 1, a quantifying section 2, a compression molding section 3 and a post-processing section 4 as in the first embodiment, but without preforming the quantified material. However, it is different in that it is injected into the cavity of the compression molding portion 3, that is, it also serves as injection means.
[0035]
The quantification unit 2 includes a pair of pressure dies 9a and 9b that are moved by an actuator, but no cavity is provided on the opposing surfaces of the pressure dies 9a and 9b. An injection valve 10 is provided in the passage 810 immediately adjacent to the injection port 91, and an extraction valve 10 'is arranged on the pressure side of the outlet side. The extraction valve 10' communicates with the compression molding section 3 by the injection passage 11 '. Is done.
When the compression molding portion 3 having the structure of the first embodiment is used, the injection passage 11 ′ protrudes forward as shown in FIG. 2 and the lower mold surface 330 of the lower slide block 3b ′ in the open state is lowered. It is provided to face '. Alternatively, it is provided so as to face the cavity at a position where it has stopped during the period from FIG. 2 to FIG. 3.
Since the other configuration is the same as that of the first embodiment, the description is incorporated.
[0036]
In the second embodiment, as shown in FIG. 6A, when the material W1 plasticized by the plasticizing part 1 is injected into the gap between the pressurizing dies 9a and 9b, the pressurizing dies 9a and 9b are moved to a predetermined stroke. It moves so that it may approach and applies a hydrostatic pressure to plasticizing material W1, and quantifies it. This quantification amount is set in consideration of the surplus amount remaining in the injection passage 11 ′.
Next, in a state where the injection valve 10 and the extraction valve 10 ′ are closed, as shown in FIG. 6B, the pressurization dies 9a and 9b are moved while the hydrostatic pressure is applied to the material, and the quantification material W2 is thus moved. Is carried to a level suitable for injection into the compression molding part 3.
[0037]
In this state, as shown in FIG. 6 (c), the extraction valves 10 ′ are opened at the same time as the opposing surfaces of the pressure dies 9a and 9b are brought into contact with each other. Thereby, the quantification material W2 is pressurized and pumped into the injection passage 11 ′, and injected into the cavity of the compression molding portion 3 or the open mold of the lower slide block 3b ′.
The subsequent steps are the same as in the first embodiment, and the quantification material W2 is heated and compressed and formed into a desired shape. When the heat compression mold has a structure as shown in FIGS. 2 to 4, since the mold is clamped by a constraining (wedge) structure and one mold is protruded from the other mold, the quantified material loading is performed. , And removal after molding is easy.
The second embodiment is suitable for molding a relatively large product or a minute product with significant deformation.
[0038]
FIG. 7 shows a third embodiment of the present invention.
In this embodiment, the compression molding section 3 is a vertical mold and is combined with the quantification section 2 of the second embodiment. The compression molding section 3 includes a heater 3h and a fixed mold having a mold surface 330 ″ on the upper surface. 3k and the outer side tapered two slide blocks 3b and 3b 'having a built-in heater 3h and a mold surface 330 on the lower surface, and the slide blocks 3b and 3b' are moved along the position of the tapered hole 31 of the holding block 3a. Actuators 3e and 3e 'are provided, and the slide block is not divided into two, but may be a single one having an injection port. Show.
[0039]
In FIG. 7A, the extraction valves 10 ′ are opened at the same time as the opposed surfaces of the pressurizing dies 9a and 9b are moved to contact each other. Thereby, the quantification material W2 is pressurized and fed to the injection passage 11 ′, and is injected into the cavity formed by the fixed mold 3k and the mold surfaces 330 ″ and 300 ″ of the slide blocks 3b and 3b ′.
In order to prevent material loss, in the third embodiment, forcible injection means 14 is preferably connected to the injection passage 11 ′. This forced injection means 14 is composed of, for example, a pressurized gas press-fitting portion, and when the quantification material W2 is pressurized and pumped to the injection passage 11 ′, it is pressed from the downstream with a pressurized fluid to quantify the material W2. Extrude. This forced injection means 14 is also applied to the second embodiment.
The quantification material W2 injected into the cavity is heated and compressed by the slide blocks 3b and 3b ′ and the fixed mold 3k which are clamped by a wedge type mold, and becomes a product.
The third embodiment is suitable for molding a dense product having a complicated shape such as being relatively large or undulating.
[0040]
【The invention's effect】
According to claim 1 of the present invention described above, the material is plasticized, the plasticized material is quantified by applying hydrostatic pressure to the plasticized material bath, and the quantified plastic material is hot compression molded. This makes it possible to mold fine parts that have been impossible with high accuracy, and further, the energy required for processing is reduced to 1/10 or less, so that the cost and energy associated with molding can be greatly reduced.
[0041]
According to claim 2, since the preform is formed at the same time as the quantification, and it is subjected to hot compression molding, it is almost runner-less, the amount of material used can be reduced, and a precise and minute product with good molding accuracy can be manufactured. Effect.
[0042]
According to the third aspect, the plasticizing unit 1 for plasticizing the material, the quantifying unit 2 for quantifying the plasticized material, and the compression molding unit 3 for heat compression molding the quantified material are provided. The quantification unit 2 includes pressure dies 9a and 9b at least one of which can be stroked by the actuator 90, and the compression molding unit 3 includes cavities 3g and 3g ′ and a heater 3h for heating the material in the cavity. 3h 'and a pair of slide blocks 3b and 3b' provided with means 3j and 3j 'for closing the cavity and applying a molding force so that the slide blocks are combined by a wedge action when the mold is clamped Therefore, by making plasticized material quantified at low pressure and moving the cavity part, it is possible to produce fine molded products with high distortion accuracy without distortion. To become conventional Compared to injection molding equipment, the amount of power used is greatly reduced to 1/10 or less, and the power consumption of mold heating and cooling accompanying the downsizing of the mold is also greatly reduced. The excellent effect that the reduction can also be achieved is obtained.
[0043]
According to the fourth and fifth aspects, it is possible to easily load the quantified material into the cavity and to remove the molded material after molding, and to obtain an excellent effect that the runner loss can be almost zero.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view showing an outline of a first embodiment of a method and apparatus for manufacturing a fine component according to the present invention.
FIG. 2 is a longitudinal sectional side view showing an example of a compression molding portion in a mold open state.
FIG. 3 is a longitudinal side view showing an example of a compression-molded part in a clamped state.
4 is a cross-sectional view taken along line IV-IV in FIG.
FIGS. 5A, 5B, and 5C are explanatory diagrams showing the operation of the quantification unit of the first embodiment in stages. FIGS.
FIGS. 6A, 6B, and 6C are explanatory views showing stepwise operations of a quantification unit and a molding unit of the second embodiment.
FIGS. 7A and 7B are explanatory views showing an embodiment and operation of a quantification unit and a molding unit of the third embodiment.
8A to 8E are explanatory views showing examples of fine products manufactured according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Plasticization part 2 Quantification part 3 Compression molding part 3b, 3b 'Slide block 3g, 3g' Cavity part 3j, 3j 'Forming force provision means 3h, 3h' Heater 9a, 9b Pressure type 90 Actuator

Claims (5)

A method for producing a fine part, comprising plasticizing a material, quantifying the plasticized material by applying hydrostatic pressure to a plasticized material bath, and subjecting the quantified plastic material to hot compression molding. The method for producing a fine part according to claim 1, wherein the preform is formed simultaneously with the quantification and is subjected to hot compression molding. A plasticizing unit 1 for plasticizing the material; a quantifying unit 2 for quantifying the plasticized material; and a compression molding unit 3 for heat-compressing the quantified material. At least one includes pressure dies 9a and 9b that can be stroked by an actuator 90. The compression molding unit 3 includes cavities 3g and 3g ', heaters 3h and 3h' that heat the material in the cavity, and the cavity. It has a pair of slide blocks 3b and 3b 'provided with means 3j and 3j' for closing and applying a forming force, and these slide blocks are configured to be united by a wedge action at the time of clamping. Special equipment for manufacturing minute parts. The apparatus for manufacturing a fine part according to claim 3, wherein the pressing dies 9a and 9b include one having a preform cavity. Either one of the slide blocks 3b and 3b 'of the compression molding part 3 is configured to protrude into a free space outside the other slide block 3b when the mold is opened. The manufacturing apparatus of the detailed component as described.

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