JP2005131798A - Manufacturing method for resin molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a resin molded product W constituted so that the dimensional shape of the resin molded product W after the reception of heat history becomes a desired shape by forming the resin molded product W into a shape preliminarily considering the heat history due to a use environment in a post process when the resin molded product W is corrected. <P>SOLUTION: This manufacturing method of the resin molded product W has a holding process for holding the resin molded product W by the predetermined clamping force of a correction member 1 so that an energy ray transmission part is brought into contact with at least either one of the deformation causing part formed in the molding process of the resin molded product W or a stress remaining part where internal stress remains, a heating process for irradiating at least either one of the deformation causing part of the resin molded product W or the stress remaining part through an energy ray transmission part in a state that the resin molded product W is held by the correction member 1 and a correction process for applying predetermined clamping force to the resin molded product W, which is irradiated with energy rays to be heated to a temperature above a thermal deformation temperature but below the melting point of the resin molded product W, by the correction member 1 to correct the resin molded product W into a shape considering heat history in the post process or under a use environment. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a method for producing a resin molded body, and more specifically, a resin molded body that is molded into a shape that takes into account thermal deformation of a molded product due to a thermal history received during a post-use environment such as assembly or mounting after molding. It is related with the manufacturing method.

As shown in FIG. 7, the resin molded body is inserted and fixed in a mold having an energy ray transmitting window, and the resin molded body is irradiated with energy rays such as infrared rays through the energy ray transmitting window. At least one infrared transmission window 21 is formed in a part of the molded product mold 20 as described above, and the resin molded body 22 is inserted into the molded product mold 20 so that the surface of the infrared transmission window 21 faces the infrared transmission window 21. It is known that the posture is fixed and the surface of the molded product is irradiated with infrared rays from an irradiation source through an infrared transmission window 21. In this case, since the resin molded body 22 is opaque to infrared rays and absorbs projection energy well, efficient heating is performed, and the mold 20 itself generates heat due to infrared irradiation. Therefore, the temperature gradient between the resin molded body 22 and the molded product mold 20 is always in the direction of cooling, so that the reversal time of the temperature gradient required in the conventional heater heating becomes unnecessary, and the processing time can be shortened. It becomes possible. (Patent Document 1)
However, in the above method, since the energy ray is irradiated to the entire resin molded body 22 or the portion to which the energy beam is irradiated is not specified, in the case of the resin molded body 22 having a relatively large shape, Because it takes time to irradiate energy beams and the energy beam irradiating device becomes larger, there is a problem that the space required for installing the device and the equipment cost increase. In the latter case, energy beam irradiation is applied to the appropriate part. There was a problem that it was not determined if it was done after reflow.

  As a means for solving such a problem, the correction restraint provided with the energy ray transmitting part in the part where the deformation of the resin molded body occurs or the part where the warp deformation is expected to occur in the usage environment due to the residual internal stress. Correction / restraining process to fix and restrain the member in close contact, and the part of the resin molded body to which the correction / restraining member is in close contact are irradiated with energy rays through the energy ray transmitting part, and a predetermined temperature not lower than the heat distortion temperature and lower than the melting point There is a correction method comprising a heating step of heating to a temperature, and in this correction method, energy beam irradiation is performed only on necessary parts, so that efficient deformation correction and internal stress relaxation can be performed in a short time. Therefore, productivity can be improved.

By the way, when a metal member or the like is pressed into the resin molded body in a later process, new deformation or internal stress is generated in the resin molded body. In such a case, if the correction method as described above is applied after press-fitting, new deformation and internal stress generated after press-fitting can be corrected and alleviated. However, there are cases where it is impossible to correct deformation or relieve internal stress by irradiation with energy rays after press-fitting due to process or device restrictions. In addition, materials with extremely high orientation, such as liquid crystal polymer (LCP), or when the internal stress remaining in the previous process is extremely large, or when the residual stress exists deep inside the resin molded body, etc. In some cases, the internal stress may not be sufficiently relaxed. In such a case, there is a problem that when the thermal history is received in a post-process (in the former case, a process after press-fitting a metal member or the like) or in a use environment, the resin molded body may be thermally deformed.
JP 2002-273762 A

  The present invention has been made in view of such a problem. When a resin molded body is corrected, it is formed in advance in a shape that takes into account the thermal history due to the use environment in the subsequent process, and after receiving the thermal history. It is providing the manufacturing method of the resin molding for the dimension shape of this resin molding to become a desired shape.

  In order to solve the above-described problem, a method for producing a resin molded body according to claim 1 of the present invention is a resin molded body using an orthodontic member provided at least in part with an energy beam transmitting portion made of an energy beam transmitting material. The resin molded body is manufactured by irradiating and heating the resin molded body with energy rays through the energy beam transmitting portion to relieve the residual stress and molding into a desired shape. A state in which at least one of a deformation generation part generated in the body molding process or a stress residual part in which internal stress remains is irradiated with energy rays through an energy ray transmission part and heated to a temperature not lower than the thermal deformation temperature and not higher than the melting point. Then, it has a straightening step of applying a predetermined tightening force by the straightening member to correct the shape in consideration of the heat history received in the post-process or in the use environment.

  In the method for producing a resin molded body according to claim 2 of the present invention, the heating step irradiates an energy beam only to a portion of the resin molded body necessary for correction of deformation and relaxation of residual internal stress. It is characterized by.

  The method for producing a resin molded body according to claim 3 of the present invention measures the dimensional shape of the resin molded body that has been straightened by the straightening process and then cooled to the melting start temperature or less, and when the predetermined shape is not reached. The method further comprises a re-correction step in which a load is applied to the resin molded body and the shape is re-corrected in consideration of thermal deformation in the use environment of the post-process.

  According to the method for producing a resin molded body according to claim 1 of the present invention, since the molded product has a correction process for correcting the resin molded body into a shape that takes into account thermal deformation under a post-process or use environment, The shape of the resin molded body after being deformed by the heat history received under the usage environment becomes a desired shape. Therefore, in order to prevent a decrease in dimensional accuracy and to prevent it, even in the case where there is a step in which new deformation or internal stress is generated in the resin molded body in which a metal member or the like is pressed into the resin molded body in the subsequent process. No need to correct again. In addition, when the material is very strong in orientation, such as liquid crystal polymer (LCP), when the internal stress is extremely large, or when the residual stress exists deep inside the resin molded body, the internal stress can be reduced by energy beam irradiation alone. Even if the relaxation is not sufficient, it is possible to prevent a decrease in the dimensional accuracy of the resin molded body due to deformation due to a thermal history received in a subsequent process or use environment.

  According to the method for manufacturing a resin molded body according to claim 2 of the present invention, in addition to the effect of claim 1 described above, even when a metal member, an electronic component, or the like is press-fitted or mounted on the resin molded body. Because the energy rays are irradiated only on the parts of the resin molded body that are necessary for correction of deformation and relaxation of residual internal stress, resin other than press-fitted and mounted metal parts and electronic parts, deformation generating parts and residual stress parts The parts of the molded body are not heated, and it is possible to prevent these parts from being subjected to unnecessary thermal effects.

  According to the method for producing a resin molded body according to claim 3 of the present invention, in addition to the effect of claim 1 described above, the dimension and shape of the resin molded body cooled to the melting start temperature or lower after being corrected by the correction process. As a result of measurement, even if it is not possible to obtain the desired size and shape taking into account the thermal history received in the post-process and the usage environment, if the predetermined size is not reached, a load is applied to the resin molded body, Therefore, the dimensional accuracy is further improved.

(Embodiment 1)
A first embodiment of the present invention will be described with reference to FIGS. 1 and 3, 1 is a correction member, 1a is an upper correction member constituting the correction member, 1b is a lower correction member constituting the correction member, 4 is a heating means, and 8 is a lower jig mounting body. , 9 is a lower mounting plate, 10 is a positioning block, 11 is an upper jig mounting plate, 12 is an upper mounting plate, 13 is a holding block, 14 is an energy beam irradiation device, 15 is a cooling pipe, 16 is a temperature sensor, 17 Is a lower jig, 46 is a cooling groove, and W, W1, and W2 are resin moldings.

  1A and 1B show a resin molded body manufacturing apparatus, in which FIG. 1A is a cross-sectional view, and FIG. 1B is a cross-sectional view taken along line CC in FIG. As shown in the figure, a lower mounting plate 9 is mounted on the upper surface side of the lower jig mounting body 8, and a lower correction member 1 b is mounted on the upper surface side of the lower mounting plate 9, thereby correcting the lower side. A positioning block 10 for positioning and fixing the resin molding W is attached to the upper surface side of the member 1b. Further, the upper mounting plate 12 is mounted on the lower surface side of the upper jig mounting body 11, the holding block 13 is mounted on the lower surface side of the upper mounting plate 12, and the upper correction member 1 is mounted on the lower surface side of the holding block 13. ing. The lower jig mounting body 8 can be moved up and down by a lifting means (not shown), and the resin molded body W is sandwiched between the upper and lower correction members 1a and 1b. The upper correcting member 1a is formed of an energy ray transmitting material, and the energy beam from the energy beam irradiation device 14 constituting the heating unit 4 is transmitted through the upper correcting member 1a to irradiate the resin molding W. I try to heat it. The lower correction member 1 may be an energy ray transmitting material or a non-transmitting material. The shapes of the portions of the upper and lower correction members 1a and 1b that are in contact with the resin molded body W are shapes that take into account the thermal history that the resin molded body W receives in the post-process and the use environment, that is, the resin molded body W in the post-process. After the internal stress remains, the shape is formed in consideration of the final deformed portion and the amount of deformation when the warp occurs due to the thermal history. In the present embodiment, the entire upper correction member 1a is made of an energy ray transmitting material, and the entire upper correction member 1a is an energy ray transmitting portion. However, the present invention is not limited to this, and resin An energy ray transmitting portion made of an energy ray transmitting material is provided at a portion of the upper correction member 1a that comes into contact with at least one of a deformation occurrence portion generated in the forming process of the formed body W or a stress remaining portion where internal stress remains. It only has to be.

As the energy beam, an optimum one depending on the material of the resin molding W, for example, ultraviolet rays (excimer laser, etc.), infrared rays (CO ₂ laser, YAG laser, halogen lamp, etc.), X-ray electron beams, heat rays, etc. You can choose. In addition, the type of the energy ray transmitting material can be appropriately selected from materials that transmit the wavelength band of the irradiated energy rays, such as zinc selenide, zinc sulfide, sapphire glass, quartz glass, and borosilicate crown glass. For example, when the resin molding W is polymethylmethacrylate (PMMA), infrared rays (CO ₂ laser) are suitably used as the energy rays, and zinc selenide is suitably used as the energy ray transmitting material.

  In the holding block 13, the cooling pipe 15 is provided in the annular cooling groove 46 to suppress the temperature of the upper correction member 1 a from rising due to heat transfer from the resin molded body W. A temperature sensor 16 is provided on the lower correction member 1b to detect the temperature of the resin molded body W. Thus, since the upper correction member 1 transmits energy rays, the temperature does not rise by irradiation with energy rays, but rises only by heat conduction from the surface of the resin molded body W that has risen in temperature by irradiation with energy rays. . Therefore, since the contact surface of the upper correction member 1a with the resin molded body W of the energy ray transmitting portion is lower in temperature than the resin molded body W whose temperature has increased due to absorption of energy rays, the cooling action of the upper correction member 1a. Thus, heat does not concentrate on the surface of the resin molded body W during heating. Therefore, discoloration / decomposition of the resin composition on the surface can be reduced.

  In addition, after the heating is completed, the correction member 1 itself does not increase in temperature due to the irradiation of energy rays. Therefore, the correction member 1 takes away the amount of heat of the resin molded body W, so that the cooling efficiency is good and quickly reaches a predetermined temperature below the heat deformation temperature. The temperature can be lowered. Therefore, while the resin molded body W is sandwiched between the correction members 1a and 1b, energy rays are irradiated to straighten the resin molded body W to correct warping, deformation, and internal stress, while improving quality and productivity. Can be increased.

  FIG. 2 shows the shape of the resin molded body W before and after the method for manufacturing a fat molded body according to the present invention, and FIG. 2 (a) is before clamping and correction by the implementation of the manufacturing method in the present embodiment. (B) shows the shape of the resin molded body W after being sandwiched and corrected by the manufacturing method according to the present embodiment, and (c) being subjected to a heat history after correction and correction. is there. As shown in FIG. 2A, the resin molded body W is a cylindrical container-like injection-molded product, and has a shape in which a cylindrical edge is connected to a circular plate. Although the resin molded body W in the present embodiment is originally injection-molded aiming at the shape shown in W1, warping as shown in W2 may occur due to the influence of residual stress and cooling conditions during molding. . The resin molded body W in the present invention can be suitably used regardless of the shape of W1 or W2. The resin molded body W is not limited to the shape of the present embodiment, and the direction of warping may occur in the opposite direction to the illustrated one depending on the thickness of the resin molded body W, the temperature distribution of the mold, and the like. There is also.

  FIG. 3 shows an outline of the correction process of the resin molded body in the present embodiment. FIG. 2A is a schematic view showing the start of heating of the resin molded body W by energy beam irradiation. Before sandwiching the resin molded body W by the correction member 1, the resin molded body W is irradiated with energy rays through the energy ray transmitting portion provided in the upper correction member 1 a.

  Next, as shown in FIG. 4B, after the resin molded body W irradiated with the energy rays reaches a predetermined temperature near the heat deformation temperature, which is equal to or lower than the heat deformation temperature, the same is illustrated in FIG. As described above, clamping and correction by the restraining members 1a and 1b are performed. Specifically, when the temperature near the deformation generating portion reaches a predetermined temperature near the thermal deformation temperature of the resin composition of the resin molded body W by measuring the temperature with the temperature sensor 16, the lower jig mounting body. A lower jig 17 having 8 is raised by a lifting means (not shown), and an upper correction member 1a and a lower correction member 1b made of an energy ray transmitting material of an upper jig 18 having an upper jig attachment body 11. Then, the resin molded body W is sandwiched and adhered to be corrected. Thus, since the resin molded body and the correction member 1a made of the energy ray transmitting material are not in close contact with each other up to a predetermined temperature near the heat distortion temperature, the heat of the surface of the resin molded body W is applied to the upper correction member 1a. The temperature can be quickly raised without diffusion, and after exceeding a predetermined temperature in the vicinity of the heat distortion temperature, the upper correction member 1a made of an energy ray transmissive material is sandwiched between the resin molded bodies W to perform correction. Thus, the upper correction member 1a can avoid decomposition and discoloration of the resin composition due to heat concentration on the surface of the resin molded body W.

  By the way, although the upper correction member 1a comes into close contact with the resin molded body W and rises in temperature due to the conduction of heat from the resin molded body W, the holding block 13 passes through the cooling pipe 15 and a cooling groove (not shown). Since the cooling medium is constantly circulated, the temperature rise during heating is small, and warping and deformation can be corrected and internal stress can be relaxed in a short time.

  Here, the deflection temperature under load is generally used as the heat distortion temperature. The predetermined temperature in the vicinity of the heat deformation temperature is preferably 10 to 30 K lower than the heat deformation temperature, and the clamping force at the time of clamping is preferably 1 to 100 kPa, particularly preferably 5 to 20 kPa. Driving (lifting / lowering) heating means (not shown) may be hydraulic, pneumatic, motor, manual press or the like. In this embodiment, the lower side is driven, but only the upper side or both may be driven.

  When the temperature in the vicinity of the deformation generating portion reaches a predetermined temperature not lower than the melting point and not higher than the melting point of the resin composition constituting the molded resin W by the temperature measurement of the temperature sensor 16, the sandwiching members 1a and 1b The irradiation heating by the energy rays is finished while maintaining the sandwiched state by and the process proceeds to the cooling step. Since the upper correction member 1a made of the energy ray transmitting material transmits the energy ray, the temperature rise at the time of irradiation rises only by heat conduction from the surface of the molded product. Accordingly, the temperature is lower than the temperature rise due to the absorption of energy rays of the resin molded body W, and since the amount of heat of the resin molded body W is taken away, the cooling efficiency is good and the temperature is quickly lowered to a predetermined temperature below the heat deformation temperature.

  Next, as shown in FIG. 6D, when the temperature of the temperature sensor 16 is measured, the temperature of the clamping member is lowered to a predetermined temperature in the vicinity of the thermal deformation temperature of the resin composition constituting the resin molded body W. , The clamping by the correction members 1a and 1b is released, and the resin molded body W is taken out.

(Embodiment 2)
A second embodiment of the present invention will be described with reference to FIGS. 4 and 5, 19 is a terminal member, W, W1, and W2 are resin moldings. In FIG. 5, 1a is an upper correction member that constitutes a correction member, and 1b is a lower correction member that constitutes a correction member. , 18 is an energy ray non-permeable material, 19 is a terminal member, 46 is a cooling groove, and W is a resin molding. Note that the basic configuration of this embodiment is the same as that of Embodiment 1, and common portions are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, an energy ray non-permeable material is provided in a part of the energy ray transmitting portion of the correction member 1 and the energy ray is applied to the resin molded body W, so that the energy ray is applied only to a portion requiring correction. The description of other parts common to the first embodiment is omitted.

  FIG. 4 shows the shape of the resin molded body W before being clamped and corrected by the production method according to this embodiment. As shown in the figure (a), the resin molded bodies W1 and W2 in the present embodiment are cylindrical container-like injection-molded products, and have a shape in which a cylindrical edge is connected on a circular plate, A terminal member 19 is press-fitted on the disk. The resin molded body in the present embodiment is originally aimed at the shape shown in W1, but may be deformed as shown in W2 due to the residual stress at the time of injection molding or the processing conditions when the terminal member 19 is press-fitted. Regardless of the presence or absence of such deformation, new internal stress due to the press-fitting of the terminal member 19 may remain in the resin molded products W1 and W2. In this case, the resin moldings W1 and W2 are deformed due to the thermal history received in the post-process or use environment.

  For this reason, the shape of the portion of the upper and lower correction members 1a, 1b in contact with the resin molded body W in the present embodiment takes into account the thermal history that the resin molded body W after press-fitting the terminal member 19 receives in a subsequent process or use environment. Formed into a shape that takes into account the final deformation site and deformation amount when warping occurs due to the addition of thermal history after internal stress remains in the resin molded body W after the terminal member 19 is press-fitted in the subsequent process. Has been. Therefore, the manufacturing method in this embodiment can be applied to the resin molded body W before being sandwiched / corrected in any shape of W1 and W2.

  In such a resin molded body W, when the energy beam is irradiated to the entire surface of the resin molded body as shown in the first embodiment, when the terminal member 19 contains a metal material, the terminal member 19 is irradiated by the energy beam irradiation. If the terminal member 19 is formed of a resin material having low heat resistance, the terminal member 19 itself or the resin molded body W may be damaged due to abnormal heating. May be melted by irradiation, resulting in damage and a decrease in dimensional accuracy.

  Therefore, as shown in FIG. 5A, an energy ray non-transmissive portion 18 is provided in the energy transmitting portion of the upper correction member 1a. The energy ray non-transmissive portion 18 is made of a material that does not allow energy rays to pass through, such as a steel plate, for example, and is a terminal member depending on the position of the terminal member 19 that is press-fitted onto the disk of the resin molded body W. 19 is arranged at a position where energy rays are not irradiated.

  If the resin molded body W is irradiated with energy rays using such an apparatus, as shown in FIG. 5 (b), the energy rays originally irradiated on the terminal member 19 are shielded by the energy ray non-transmissive portion 18, Energy rays are irradiated only on the necessary parts of the resin molded body W. That is, since the energy rays are irradiated only on the portions of the resin molded body W necessary for correction of deformation and relaxation of the remaining internal stress, the press-fitted terminal member is not heated and unnecessary for these portions. Application of heat effects can be prevented.

  Furthermore, it is preferable to dispose the energy ray non-transmitting portion 18 in a portion where the energy ray is not irradiated other than the deformation occurrence portion and the residual stress portion of the resin molded body W. Thereby, a deformation | transformation and internal stress remain | survive in the resin molding W, and the provision of the heat influence to the part which does not need the irradiation of an energy beam can be prevented. In addition, regarding a series of processes from the sandwiching of the resin molded body W by the correction members 1a and 1b, which is a subsequent process, to the removal of the resin molded body W from the correction member 1, FIG. 3B to FIG. Since it is the same as Embodiment 1 demonstrated, description in this embodiment is abbreviate | omitted.

  Further, the shape of the resin molded body W is not limited to this embodiment, and the direction of deformation may occur in the opposite direction to that shown in the figure depending on the thickness of the resin molded body W, the temperature distribution of the mold, and the like. There is also. Further, in the present embodiment, the terminal member is disposed on the disk, but is not limited to this, and may be a metal component or an electronic component mounted on the disk. In addition, the invention according to this embodiment can be suitably used for a mounting member that generates residual stress or deformation in the resin molded product W by mounting on the resin molded product W.

(Embodiment 3)
A third embodiment of the present invention will be described with reference to FIG. FIG. 6 shows the outline of the re-correction process of the resin molded body W by the re-correction device. In the figure, 20 is a re-correcting device, 21 is a punch, 22 is a die, and W is a resin molding.

  The resin molded body W that has been cooled after correction by the method for producing a resin molded body shown in the first and second embodiments varies in residual internal stress due to variations in irradiation conditions of energy rays and variations in cooling conditions. When it is taken out from the correction member 1a as shown in FIG. 5, the dimensional accuracy may vary due to the variation in the degree of contraction. If the thermal history is subsequently received with such a variation in dimensional accuracy, the final dimensions of the resin molded product also vary. Therefore, the resin molded body W that has been cooled after correction by the method for manufacturing a resin molded body shown in Embodiments 1 and 2 is measured by a dimension measuring device (not shown) to obtain a desired dimensional accuracy. As a result of the measurement, for the resin molded body W in which a desired dimension and shape are not obtained, the re-correction apparatus shown in FIG. 6 uses the original target shape, that is, the post-process described in the first and second embodiments. Correct the shape again in consideration of thermal deformation under the usage environment. Specifically, re-correction is performed by fixing the resin molded body W to the die 22 and pressurizing with the punch 21. The pressurizing condition by the punch 21 is determined according to the difference between the measured value obtained from the above-described dimension measurement result and the originally intended dimension. For example, when the difference is large, the pressure is increased, and when the difference is small, the pressure is decreased. The drive control unit of the punch 21 (not shown) has a database of the relationship between the dimensional difference value and the pressure to be applied, and the drive control unit performs pressure control for re-correction.

It is explanatory drawing which shows the manufacturing apparatus of the resin molding in Embodiment 1. FIG. It is explanatory drawing which shows the shape of the resin molding before and behind the manufacturing method of the fat molding in Embodiment 1. FIG. It is explanatory drawing which shows the outline of the correction | amendment process of the resin molding in Embodiment 1. FIG. It is explanatory drawing which shows the shape of the resin molding before being pinched and corrected by implementation of the manufacturing method in Embodiment 2. It is explanatory drawing which shows the manufacturing apparatus of the resin molding in Embodiment 2. It is explanatory drawing which shows the outline of the recorrection process of the resin molding by the apparatus for recorrection in Embodiment 3. FIG. It is the schematic which shows a prior art example.

Explanation of symbols

1 Straightening member W Resin molding

Claims (3)

In a state where the resin molded body is sandwiched by an orthodontic member provided at least in part with an energy beam transmitting portion made of an energy beam transmitting material, the resin molded body is irradiated with energy rays and heated via the energy beam transmitting section. A method for producing a resin molded body that relieves residual stress and molds it into a desired shape,
At least one of the deformation generation part generated in the molding process of the resin molded body or the stress residual part where internal stress remains is irradiated with energy rays through the energy ray transmission part and heated to a temperature not lower than the heat deformation temperature and not higher than the melting point. A method for producing a resin molded body, comprising: a straightening step in which a predetermined tightening force is applied by the straightening member to correct the shape in consideration of a thermal history received in a post-process or a use environment.   2. The method for producing a resin molded body according to claim 1, wherein the heating step irradiates an energy beam only to a portion of the resin molded body necessary for correction of deformation and relaxation of residual internal stress. .   Measure the size and shape of the resin molded product that has been corrected by the correction process and then cooled below the melting start temperature. If it does not meet the specified dimensions, a load is applied to the resin molded product, The method for producing a resin molded body according to claim 1, further comprising a re-correction step of correcting the shape again in consideration of the thermal deformation below.

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