JP3788006B2 - Multilayer molding method and multilayer molding apparatus for resin - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, after the first layer core material molten resin is injected and filled into the mold to obtain the first layer core material filler, the second layer intermediate material molten resin is applied to the surface of the first layer core material filler. And a multilayer molding method and a multilayer molding apparatus for a resin in which a decorative skin material is fused and integrated on the surface of a second layer intermediate material.
[0002]
[Prior art]
In recent years, more and more added value is required for resin molded parts used in automobiles, home appliances, building materials and the like. Along with the demand for added value such as feel and texture as well as softness and cushioning properties, there is an increasing demand for cost reduction by reducing the number of molding processes. In order to cope with these, conventionally, the following multilayer molding has been carried out. That is,
(1) Insert and set the skin material (decorative material) in the mold and inject and fill the core material in the mold-clamped or mold-opened state, and then apply the injection holding pressure or mold-clamping force and apply the core material. Cool down. By waiting for the completion of cooling and removing the molded product after opening the mold, a surface decorative molded product is obtained in which the skin material (decorative material) is fused and integrated on the surface of the core resin molded product ( Skin material insert molding).
(2) Injection and filling of the first layer resin (core material) into the mold, and injecting the second layer resin (decorative material) in a state where part or the entire surface of the mold is retracted or the clamping force is reduced. After filling, injection holding pressure or mold clamping force is applied and the filled resin is cooled. By waiting for the completion of cooling and taking out the molded product after opening the mold, a surface decorative molded product in which the decorative resin is laminated and integrated on the surface of the core material resin is obtained (sandwich molding).
[0003]
[Problems to be solved by the invention]
However, such a conventional method has the following problems.
(1) In the case of skin material insert molding, a skin material with a foam layer laminated on the back surface (core material resin side) is used to give a soft feeling and cushioning properties. The foamed layer is easily melted away by the material resin, and the soft feeling and cushioning properties are lost. As a countermeasure, a skin material in which a protective layer having heat resistance and pressure resistance is laminated on the back surface of the foam layer is used. However, the cost of the skin material is increased and it is difficult to completely protect the foam layer.
In addition, skin materials such as brushed fabrics and woven fabrics are used to provide a feeling of touch and texture, but the skin materials are damaged by the load of the core material resin at high temperature and high pressure during molding (for example, It was difficult to maintain the original texture (feel and texture) of the skin material even after molding.
(2) Even in sandwich molding, a feeling of touch and texture are often required, but it is not possible to give a feeling of touch and texture only with a molding resin. Brushed or woven fabrics are ideal for decorating materials as a way to give a feeling of touch and texture, and conventional sandwich molding could not be used.
When a soft feeling, cushioning property, touch feeling and texture are required at the same time, it has been difficult to cope with the conventional molding method.
(3) As one of multifunctional molded products for which demand is expected to increase in the future, for high-quality multilayer molded products that combine softness and cushioning with the feel and texture, It is extremely difficult to cope with the molding method.
[0004]
[Means for Solving the Problems]
In order to solve the above problems and obtain a resin multilayer molded product stably with high quality by simple control, in the present invention, the first invention is formed between a pair of opposed molds. When a molten resin as a core material is injected and filled into a mold cavity space to form a first layer filling material, a resin as a second layer intermediate material is laminated on the surface of the first layer filling material. At the same time, in a resin multilayer molding method in which a decorative skin material is fused and integrated on the surface of the second layer intermediate material,
For the decorative layer of the skin material, a material having a glass transition point lower than the temperature at the time of injection of the second layer intermediate material resin is selected, and the core material is placed in the mold cavity space in the preset first clamping state. After the first layer core material molten resin is injected and filled to form the first layer filling, the two molds are relatively spaced apart and held at a predetermined mold opening amount setting value. A skin material is interposed between the layer filler and the mold, and subsequently becomes an intermediate material in a space formed by the first layer filler and the skin material in a preset second clamping state. After injecting and filling the second layer intermediate material molten resin, the surface of the skin material decorating layer or the second layer intermediate material resin is set to a preset temperature within the temperature range indicating the rubbery elasticity of the skin material decorating layer. set at the time the temperature monitor value reaches, between the skin material and the mold, the gap damaged decorative layer is to ensure a space for elastic recovery of Te, it was decided to hold the set time.
[0005]
In the second invention, the first mold clamping state is such that the mold clamping force that does not open the mold due to the resin pressure of the filled first layer core material molten resin is used until the mold filling is completed. It was decided to load and hold.
In the third invention, the first mold clamping state is the first mold clamping force that allows the mold to be opened by the resin pressure of the filled first layer core material molten resin during injection filling. Then, the second mold clamping force for the purpose of shaping the first layer core material resin was loaded on the mold.
[0006]
In the fourth invention, in the first mold clamping state, the two molds are held at a predetermined mold opening amount set value during injection filling, and thereafter the first layer core material resin is applied. A mold clamping force for the purpose of shape was applied to the mold.
Furthermore, in the fifth invention, the second mold clamping state is such that a mold clamping force that does not open the mold due to the resin pressure of the filled second layer intermediate material molten resin is applied to the mold until the injection filling is completed. It was decided to load and hold.
[0007]
In the sixth invention, in the second mold clamping state, the mold is loaded with a first mold clamping force that allows the mold to open with the resin pressure of the filled second layer intermediate material molten resin, After that, the second mold clamping force was applied to the mold for the purpose of shaping the second layer intermediate resin and fusing and integrating the skin material, the first layer core material, and the second layer intermediate material. .
In the seventh invention, in the second mold clamping state, the two molds are held relatively apart from each other at a predetermined mold opening amount set value during injection filling, and thereafter the second layer intermediate material resin is applied. A mold clamping force for the purpose of fusion and integration of the shape, the skin material, the first layer core material and the second layer intermediate material was applied to the mold.
[0009]
In the eighth invention, a multilayer injection mechanism for injecting and filling a first layer core material and a second layer intermediate material molten resin into a mold cavity space formed by a movable mold and a fixed mold, and a skin material as the mold A loading / unloading mechanism that interposes the mold and unloads the multilayer molded product out of the mold; and the first and second mold clamping states when the first layer core material and the second layer intermediate material molten resin are injected and filled. the clamping force sets a multistage or mold opening amount in multiple stages, a first-type opening amount when interposing the skin material to gold in the mold, the decorative damaged between the said surface skin material and the mold a mold clamping condition setting unit layers are set and input a second type opening amount to the gap to ensure a space for elastic recovery, the mold clamping control state at a temperature in the region exhibiting rubber-like elasticity of said surface skin material decorative layer Temperature condition input part to set and input the temperature to be switched, and the surface temperature of the decorative material layer during molding or the second layer A temperature monitoring unit for monitoring between material resin surface temperature, timing of switching by comparing a set value of a signal of the temperature monitoring unit and the temperature condition input section to the mold clamping control unit from the second mold clamping state to the second type opening degree Based on the signals from the comparison control unit that emits a signal, the mold opening amount detection unit that detects the mold opening amount, the pressure detection unit that detects the mold clamping force, and the comparison control unit and the mold clamping condition setting unit, And a mold clamping control unit to be controlled.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, for the decorative layer of the skin material, a material having a glass transition point lower than the temperature at the time of injection of the second layer resin (intermediate layer) is selected, and the first layer resin (core layer) is injected and filled. Then, once the mold is opened, the skin material (decorative layer) is clamped in a state of being inserted and set in the mold. Subsequently, after injecting and filling the second layer resin (intermediate layer), the mold clamping force is applied and the temperature detected by the skin decoration layer of the temperature monitor value indicates the rubbery elasticity of the skin decoration layer When the set temperature is reached, the load applied to the skin decoration layer is removed, and a gap is provided in the mold to secure a space where the damaged decoration layer can be elastically restored. To do.
By doing so, the skin material decoration layer damaged by an external force during molding (loading of high temperature / high pressure intermediate layer resin) is recovered by elastic force, and the original texture of the skin material is secured. Waiting for the cooling of the core layer / intermediate layer resin to finish, and then removing the molded product after mold opening, the core layer / intermediate layer / surface decoration layer are fused together and the original texture of the skin material is maintained. Thus, a high-quality multilayer molded product can be obtained efficiently and stably.
[0011]
Moreover, in this invention, the material of each layer can be selected according to the quality and function requested | required of a molded article, and it becomes possible to provide surface decoration performance freely by these combination.
For example, hard core resin (maintenance of molded product shape and imparting strength) to the core layer, foamed resin or soft resin (providing softness and cushioning) to the intermediate layer, and brushed or woven fabric (hand feel) to the skin decoration layer By selecting “Applying feel and texture”, softness, cushioning, and feel and texture can be imparted at the same time without using the conventional heat-resistant / pressure-resistant protective layer lamination process. It was possible to efficiently and stably supply the skin-decorated molded product that was possible.
[0012]
By controlling the mold clamping force or mold opening amount in multiple stages as needed during the injection filling of the first layer resin and the second layer resin, the flow rate of the resin and the resin pressure during the injection filling can be kept low. It is possible to reduce the pressure inside the mold and the injection filling time. As a result, damage to the skin material during molding can be kept low, so the time required for the decorative layer damage recovery process can be shortened, and the resin pressure in the mold can be made uniform by holding pressure from the mold clamping side. Thus, a molded product free from deformation and warpage can be obtained, and a high-quality molded product excellent in surface decoration performance can be obtained.
[0013]
When the temperature monitor value is the temperature of the second layer intermediate resin, even if the temperature of the skin decoration layer is cooled below the glass transition point, the amount of heat possessed by the second layer intermediate resin Due to the heat transfer blocking effect from the skin material to the mold due to the gap provided in the mold, the skin material decoration layer is reheated to a temperature region exhibiting rubbery elasticity above the glass transition point. Thereby, a damaged part can self-recover by the rubber-like elastic force of a skin material decoration layer.
In this case, the load of the mold clamping force for the purpose of fusion integration and shaping of the first layer core material resin, the second layer intermediate material resin, and the skin material can be continued for a longer time. Therefore, a high-quality molded product having an excellent surface decoration performance can be obtained efficiently and stably.
[0014]
【Example】
Details of embodiments of the present invention will be described below with reference to the drawings. 1 to 4 relate to an embodiment of the present invention, FIG. 1 is an overall configuration diagram of a resin multilayer molding apparatus, FIGS. 2 and 3 are flowcharts of a resin multilayer molding process, and FIG. 4 is a multilayer molding molding operation. It is operation | movement explanatory drawing for demonstrating.
[0015]
As shown in FIG. 1, a multilayer molding apparatus 100 according to the present invention includes a mold apparatus 10, a mold clamping apparatus 20, an injection apparatus 30, a control apparatus 60, and an unillustrated skin material and molded product carry-in / out apparatus. .
The mold apparatus 10 includes a fixed mold 3 attached to the fixed platen 1 and a movable mold 4 attached to the movable platen 2, and the movable platen 2 and the movable mold 4 are mold clamping cylinders of the mold clamping device 20. 22 is configured to be able to move forward and backward.
In this embodiment, the horizontal clamping method is used, but a rigid clamping method is also possible.
The mold clamping apparatus 20 includes a mold clamping cylinder 22 that operates to open and close the molds 3 and 4 of the mold apparatus 10, and the movable mold 4 is a tie bar (not shown) with respect to the fixed mold 3. Go forward and backward as guided by.
[0016]
The injection device 30 includes a first injection unit 30A for supplying the first layer core material molten resin into the cavity 5 and a second injection unit 30B for supplying the second layer intermediate material molten resin into the cavity 5, and each of them is fixed. The molten resin can be supplied through a path connected to the cavity 5 from the side and the lower side of the mold 3. Each path is provided with shut-off valves 31A and 31B for blocking and communicating the resin flow path.
[0017]
Next, the control device 60 will be described. As shown in FIG. 1, the control device 60 includes a mold clamping condition setting unit 61, a mold clamping control unit 62, an injection control unit 63, a temperature condition input unit 64, a comparison control unit 65, a temperature monitoring unit 66, a temperature sensor 67, The mold opening amount detection unit 68, a mold position sensor 69, a pressure detection unit 70, a resin pressure sensor 71, a hydraulic control valve 80, a hydraulic pressure supply source 90, and the like.
The pressure information measured by the resin pressure sensor 71 arranged on the fixed mold 3 and the position information of the mold position sensor 69 for detecting the mold opening amount between the molds 3 and 4 are input to the mold clamping control unit 62. Then, an operation signal is given to the mold clamping cylinder 22 of the mold clamping device 20 via the hydraulic control valve 80A. Reference numeral 90 denotes a hydraulic pressure supply source.
The skin material decoration layer temperature information measured by the temperature sensor 67 (if the intermediate material resin temperature information is detected, the temperature sensor 67 is disposed on the intermediate material resin side) is passed through the temperature monitor unit 66. It is connected to the mold clamping control unit 62 via the temperature condition input unit 64 and the comparison control unit 65.
[0018]
2 and 3 show a flowchart of the resin multi-layer molding process, and the outline thereof will be described below.
The first mold clamping state has the following three patterns, and one of them is selected.
[0019]
Pattern A is a method in which mold clamping is performed with a mold clamping force that does not generate burrs when the first layer resin is injected and filled, and this state is maintained until injection and filling are completed. This pattern A is selected when a high-fluidity resin is employed as the first layer resin or when the mold shape is easy to flow.
The pattern B is injected and filled in a state in which the mold is clamped with a small clamping force so that the mold is appropriately opened when the first layer resin is injected and filled. In this method, the first layer resin is shaped by increasing the clamping force at an arbitrary time during injection filling or when injection filling is completed. This pattern B is selected when a low flow resin is employed as the first layer resin, or when it is difficult to flow, such as a mold shape or a thin wall shape. In addition to the pressure control for shaping the first layer resin by the load of the mold clamping force, the same shaping is also performed by means (position control) for holding the mold clamping position setting value so as to give a compression (shaping) action. A shape effect can be obtained.
The pattern C is injected and filled with the first layer resin in a state where the mold is clamped and held at a predetermined mold opening position. In this method, the first layer resin is shaped by applying a clamping force at an arbitrary time during injection filling or at the completion of injection filling. This pattern C is selected when a low-fluidity resin is employed as the first layer resin. In this case as well, the first layer resin can be shaped by position control in the same manner as the pattern B.
[0020]
When pattern B or pattern C is selected, the mold opens slightly during injection filling, so that the resin flow path in the mold is enlarged and easy to flow, and air and gas escape from the mold is improved. Filling behavior is smooth. Accordingly, the injection filling pressure is lowered, the injection time is shortened, the resin temperature during filling is reduced, and the molding cycle can be shortened.
[0021]
The second mold clamping state has the following three patterns, and one of them is selected.
Pattern D is a method of clamping the mold with a clamping force that does not generate burrs when the second layer resin is injected and filled, and holding this state until the completion of injection and filling. This pattern D is selected when a high-fluidity resin is employed as the second layer resin or when the mold shape is easy to flow.
The pattern E is injected and filled in a state in which the mold is clamped with a small clamping force so that the mold is appropriately opened when the second layer resin is injected and filled. In this method, the mold clamping force is increased at any time during injection filling or when injection filling is completed, and the second layer resin is shaped and the skin material / intermediate material / core material is fused and integrated. Because the mold opens slightly during injection filling, the resin flow path in the mold expands and flows easily, the resin pressure can be kept low, and the thermal and pressure external force applied to the skin material is reduced. . Therefore, damage to the skin material during the injection filling of the second layer resin can be reduced.
The pattern F is injection-filled with the second layer resin in a state where the mold is clamped and held at a predetermined mold opening position. This is a method in which a mold clamping force is applied at an arbitrary time during injection filling or at the completion of injection filling to form the second layer resin and fuse and integrate the skin material, intermediate material, and core material. The effect of preventing damage to the skin material is higher than that of the pattern D, and in particular, the effect of preventing damage to the skin material near the gate portion during injection filling is great.
In the patterns E and F, similarly to the pattern B, the second layer resin can be shaped and the skin material / intermediate material / core material can be fused and integrated by the position control method.
[0022]
Appropriate mold opening amount during injection filling in patterns C and F differs depending on the gate shape, mold structure, skin material type and injection conditions, and the mold does not leak molten resin in the cavity even when the mold is opened. A type structure is required.
Based on the above, as the first layer core material resin, a resin having poor fluidity (for example, ABS resin) or a second layer intermediate material resin from among hard resin materials for the purpose of maintaining the shape of the molded product or imparting strength. From a soft resin material for the purpose of giving a soft feeling and cushioning, an elastomer, and from a PET skin material with a raised layer from a decorative material for the purpose of giving a feeling of touch and luxury as a decorative layer Taking the laminated molded product as an example, the actual operation of the molding operation will be described.
The most important thing for the present invention is the material selection of the skin material decoration layer. That is, in order to utilize the damage recovery phenomenon of the decorative layer by the elastic force, when the glass transition temperature of the decorative layer (for PET T _g = 70~80 ℃) is the temperature (elastomer injection time of intermediate members resin Usually, it is lower than 200 to 220 ° C.).
Since resin with poor fluidity is used as the core material, the pattern C is selected as the first mold clamping state. A PET skin material having a raised layer is used as a decorative layer, and pattern F is selected as the second mold clamping state in order to prevent melting of the skin material near the gate portion.
[0023]
From the injection conditions such as the injection condition of the first layer core material resin and the injection condition of the second layer intermediate material resin, the mold opening amount setting value (Q1) and the mold clamping position control in the pattern C which is the first mold clamping state Timing of switching to mold clamping force control (R2), set mold clamping force (P4), mold opening amount setting value (Q2) that is the mold opening amount when the skin material is inserted into the mold, and the second mold clamping Mold opening amount setting value (Q3) in pattern F, which is the state, timing for switching from mold clamping position control to mold clamping force control (R4), mold clamping conditions such as set clamping force (P8), skin material decoration The mold clamping conditions such as the mold opening amount setting value (Q4) in the layer damage recovery process and the cooling holding conditions such as the cooling holding time of the first layer core material resin are input and set.
[0024]
After the initial conditions have been set as described above, the actual operation molding operation is started. As shown in FIGS. 2, 3 and 4, the procedure is as follows.
(A) The mold clamping operation is performed corresponding to the mold opening amount set value (Q1) set by the mold clamping condition setting unit 61. After the detection signal of the mold opening amount sensor 69 reaches the set value, the position holding control is performed by controlling the hydraulic pressure of the mold clamping cylinder 22 so as to hold the set value (Q1).
(B) The shutoff valve 31A of the first injection unit 30A is opened, and the molten resin of the first layer serving as the core material is injected and filled into the mold cavity.
At this time, since injection filling is performed in the mold open state, the pressure deviation of the resin in the mold cavity is eliminated, and a high-quality core molded body with less residual distortion and no deformation / warpage is obtained. By reducing the resin pressure in the mold cavity, high-speed injection filling is possible, and as a result, injection filling is performed in a state in which the temperature of the resin is low, and high quality of the core molded body is promoted.
The mold clamping operation is started by the timing signal (R2) set by the mold clamping condition setting unit 61, and the first layer resin is shaped by the set mold clamping force (P4) load. Note that the timing signal (R2) is set at an arbitrary time during the injection filling operation, such as the elapsed time from the start of injection, the stroke of the injection cylinder, and the like. Accordingly, the shut-off valve 31A of the first injection unit 30A is closed when the set mold clamping force (P4) is loaded (to prevent backflow of the filled resin).
[0025]
(C) The mold opening operation is performed based on the mold clamping condition previously set by the mold clamping condition setting unit 61. Note that the mold opening operation takes a cooling holding time set at an arbitrary time immediately after the completion of filling in consideration of adhesiveness with the second layer intermediate resin according to the cooling and solidification state of the first layer molten resin. Performed after elapse.
If the cooling holding time is too short, the first layer core resin is not sufficiently shaped. On the other hand, if the length is too long, the fused state between the first layer core resin and the second layer intermediate material resin becomes insufficient, leading to a decrease in strength.
The mold opening operation is performed corresponding to the mold opening amount setting value (Q2) set by the mold clamping condition setting unit 61. After the detection signal of the mold opening amount sensor 69 reaches the set value, the position holding control is performed by controlling the hydraulic pressure of the mold clamping cylinder 22 so as to hold the set value (Q2).
Next, the skin material is inserted and set between the movable mold in the mold open state and the first layer core resin molded body by a skin material carrying device (not shown). In addition, the form of a skin material uses what was roughly preformed in the shape of a sheet or a mold. In addition, as a setting method to the mold, a suitable one from vacuum suction, needle stick, core presser and the like is used.
After the skin material is inserted and set, the mold clamping operation is performed in accordance with the mold opening amount setting value (Q3) set by the mold clamping condition setting unit 61.
After the detection signal of the mold opening amount sensor 69 reaches the set value (Q3), the position holding control is performed by controlling the hydraulic pressure of the mold clamping cylinder 22 so as to hold the set value (Q3).
[0026]
(D) The shutoff valve 31B of the second injection unit 30B is opened, and the second layer molten resin as an intermediate material is injected and filled into the secondary space formed by the core molded body and the movable mold / skin material. To do.
Here, since the second layer intermediate material resin is injected and filled in a state where the mold is opened with the mold opening amount Q3, the resin pressure in the mold cavity is reduced and the resin pressure in the gate portion is kept low. In addition, it is possible to prevent melting of the skin material near the gate portion.
[0027]
(E) In response to the timing signal (R4) set by the mold clamping condition setting unit 61, the mold clamping operation is started and a set mold clamping force (P8) is applied. The timing signal (R4) can be set at any time during injection filling as in R2, but in this embodiment, it is set as the time of completion of injection filling. Therefore, also in this case, the shutoff valve 31B of the second injection unit 30B is closed.
The set clamping force (P8) is applied for the purpose of shaping the second layer molten resin (intermediate material) and fusing and integrating the skin material, intermediate material, and core material (shaping of the multilayer molded product). Process). The skin material is heated by the heat amount of the intermediate material resin simultaneously with the injection filling of the intermediate material resin, and further, the skin material is damaged by the load of the high temperature and high pressure intermediate material resin at the same time when the load of the mold clamping force (P8) is started. .
If this clamping force holding time is long, the formability of the multilayer molded body is improved, but the degree of damage to the skin material decorative layer is increased. On the contrary, if this holding time is shortened, the damage to the skin material decoration layer is reduced, but the shapeability of the multilayer molded article is deteriorated. That is, the prevention of damage to the skin material and the improvement of the shapeability of the multilayer molded article are contradictory control objects, and it has been extremely difficult to achieve this balance.
[0028]
In the present invention, a material having a glass transition point lower than the temperature at the time of injection of the second layer intermediate material resin is selected as the decorative layer of the skin material, and at the same time as the load of the set clamping force (P8) is started. The temperature M set in the temperature (temperature above the glass transition point) region where the skin decoration layer temperature is monitored by the temperature sensor 67 and the skin decoration layer during the shaping process of the multilayer molded article exhibits rubber-like elasticity. When the monitor temperature reaches the temperature, the above-mentioned mold clamping force is removed and the set mold opening amount (Q4) is held for a set time (T), so that the decorative layer of the skin material damaged during molding is elastic. By adopting a molding control method that recovers by force and ensures the original texture of the skin material, it balances the formability of the multilayer molded body and the prevention of damage to the skin material.
Here, the set temperature (M) is sufficient for the cooling and solidification of the intermediate resin and the fusion / integration of the skin material / intermediate material / core material (that is, the formability of the multilayer molded product), and the skin material decoration. Within the temperature range where the layer exhibits rubbery elasticity, the temperature is set as a temperature condition for recovering the damage to the skin material decoration layer received during molding.
The set die opening (Q4) is equal to or greater than the thickness of the skin material including the skin material decoration layer, and the space between the mold and the skin material is provided, and the recovery space due to the elastic force of the skin material decoration layer is reduced. It is set for the purpose of ensuring and securing a temperature holding time showing rubber-like elasticity by blocking heat transfer between the mold and the decorative layer.
Setting time (T) is the time recovery by the elastic force (i.e., the range of cooling time from the set temperature (M) to the glass transition temperature T _g), the cooling process of the intermediate material (or core material) in the conventional molding Since it was confirmed by experiment that it was within the set time range, the cooling time for the intermediate resin was the same.
In addition, when the temperature monitor value is the intermediate material resin temperature, even if the skin material decoration layer temperature is cooled to T _g or less, the heat transfer blocking effect by the set mold opening (Q4) and the intermediate material resin With the amount of heat, the skin material decoration layer is reheated to T _g or more, and a recovery state due to rubber-like elasticity is achieved. In this case, since the load time of the set mold clamping force (P8) can be continued for a long time, the shapeability of the multilayer molded body is significantly improved.
[0029]
(F) After the set time (T) has elapsed, the mold is opened and the molded product is taken out by a molded product take-out device (not shown) to complete one molding cycle.
In addition to the above description, the command for the mold clamping condition switching timing to the set mold opening amount (Q4) by detecting the set temperature (M) is, for example, from the start of the injection of the intermediate material resin to the set temperature (M). The arrival time can be measured by several molding tries, and the elapsed time of the measurement result can be used as a switching timing command. In this case, control can be simplified.
In addition, the shaping of the core material resin and the shaping of the multilayer molded body have been performed with the load of the mold clamping force from the mold clamping side (patterns B and C and patterns E and F). The same effect can be obtained by using together with the load or only by holding pressure on the injection side. However, in this case, the effect due to the uniform pressure-holding action from the whole mold clamping side cannot be expected.
[0030]
Furthermore, for example, when a foamable resin is used as the second layer intermediate material resin, position control based on multistage mold opening amount setting values and mold opening control based on micro mold clamping force settings are employed in the second mold clamping state. As a result, the expansion ratio can be controlled.
In this case, the volume occupied by the second layer intermediate resin (foamable resin) can be controlled by controlling the mold opening amount at the completion of filling relative to the mold opening amount at the start of injection filling of the second layer intermediate resin. This makes it possible to control the expansion ratio.
Moreover, as a skin material, a printing film, a leather-like sheet | seat, etc. can also be used. You may affix a skin material on both surfaces or the whole surface. In addition to the two-layer resin of the core material and the intermediate material, another resin layer may be provided.
[0031]
【The invention's effect】
As described above, in the present invention, the following excellent effects can be exhibited.
(1) The surface decoration can be freely expressed by selecting and combining the material of each layer of the first layer core material resin, the second layer intermediate material resin, and the decorative skin material, which can be handled by the conventional multilayer molding method. It became possible to produce multi-layer molded products that had a soft feeling, cushioning properties and feel and texture.
(2) Decorating a high-quality surface without damage to the skin material by utilizing recovery behavior due to rubbery elasticity, multistage control of mold clamping force and mold opening, and selection of molding conditions suitable for molding resin and skin material It is possible to efficiently and stably obtain a molded product with high added value.
(3) The core material resin, intermediate material resin, and skin material are completely free from deformation and warping due to the uniform pressure-holding action across the entire surface of the mold cavity from the mold clamping side and the load of sufficient mold clamping force. It is possible to obtain a very good skin material insert-molded product integrated by fusion.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a resin multilayer molding apparatus according to an embodiment of the present invention.
FIG. 2 is a flowchart of the first half of a resin multilayer molding process according to an embodiment of the present invention.
FIG. 3 is a flowchart of the latter half of the resin multi-layer molding process according to the embodiment of the present invention.
FIG. 4 is an operation explanatory diagram for explaining a molding operation according to the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fixed platen 2 Movable platen 3 Fixed metal mold 4 Movable metal mold 5 Cavity 10 Mold apparatus 20 Clamping apparatus 22 Clamping cylinder 30 Injection apparatus 30A 1st injection unit 30B 2nd injection unit 31A Shutoff valve (1st injection unit )
31B Shut-off valve (second injection unit)
60 Control Device 61 Mold Clamping Condition Setting Unit 62 Mold Clamping Control Unit 63 Injection Control Unit 64 Temperature Condition Input Unit 65 Comparison Control Unit 66 Temperature Monitor Unit 67 Temperature Sensor 68 Mold Opening Detection Unit 69 Mold Position Sensor 70 Pressure Detection Unit 71 Resin pressure sensors 80A, 80B, 80C Hydraulic control valves 90A, 90B, 90C Hydraulic supply source 100 Multilayer molding apparatus M Set temperatures P1, P2, P3, P4, P5, P6, P7, P8 Mold clamping force set values Q1, Q2, Q3, Q4 type opening amount setting value R1, R2, R3, R4 Timing setting value T Setting time

Claims (8)

After a molten resin serving as a core material is injected and filled into a mold cavity space formed between a pair of opposing molds to form a first layer filling, a resin serving as a second layer intermediate material is added to the first layer filling material. In the multilayer molding method of resin in which the decorative skin material is fused and integrated with the surface of the second layer intermediate material while being laminated on the surface of the layer filler,
For the decorative layer of the skin material, a material having a glass transition point lower than the temperature at the time of the injection of the second layer intermediate material resin is selected, and the core material is placed in the mold cavity space in the preset first clamping state. After the first layer core material molten resin is injected and filled to form the first layer filling, the two molds are relatively spaced apart and held at a predetermined mold opening amount setting value. A skin material is interposed between the layer filler and the mold, and subsequently becomes an intermediate material in a space formed by the first layer filler and the skin material in a preset second clamping state. After injecting and filling the second layer intermediate material molten resin, the surface of the skin material decorating layer or the second layer intermediate material resin is set to a preset temperature within the temperature range indicating the rubbery elasticity of the skin material decorating layer. set at the time the temperature monitor value reaches, between the skin material and the mold, the gap damaged decorative layer is to ensure a space for elastic recovery of Te, multilayer molding method of the resin, characterized in that holding the set time. The first mold clamping state is such that a mold clamping force that does not open the mold by the resin pressure of the filled first layer core material molten resin is loaded and held on the mold until injection filling is completed. A multilayer molding method of the resin described. In the first mold clamping state, a first mold clamping force that allows the mold to open with the resin pressure of the filled first layer core material molten resin is applied to the mold during injection filling, and thereafter The method according to claim 1, wherein a second clamping force is applied to the mold for the purpose of shaping the first layer core material resin. In the first mold-clamping state, both molds are held at a predetermined mold opening amount set value during injection filling, and thereafter a mold-clamping force for shaping the first layer core material resin is applied. The method for multilayer molding of resin according to claim 1, wherein the mold is loaded. 2. The second mold clamping state is such that a mold clamping force that does not open the mold due to the resin pressure of the filled second layer intermediate material molten resin is loaded and held on the mold until injection filling is completed. Multilayer molding method of resin. In the second mold clamping state, a first mold clamping force that allows the mold to open is applied to the mold by the resin pressure of the filled second layer intermediate material molten resin, and then the second layer intermediate The resin multilayer according to claim 1, wherein a second mold clamping force is applied to the mold for the purpose of shaping the material resin and fusing and integrating the skin material, the first layer core material and the second layer intermediate material. Molding method. In the second mold clamping state, both molds are held relatively apart at a predetermined mold opening amount set value during injection filling, and thereafter, molding of the second layer intermediate material resin, skin material, 2. The method for multi-molding a resin according to claim 1, wherein a mold clamping force for the purpose of fusing and integrating the first layer core material and the second layer intermediate material is applied to the mold. A multilayer injection mechanism for injecting and filling a first layer core material and a second layer intermediate material molten resin into a mold cavity space formed by a movable mold and a fixed mold, and a skin material interposed in the mold A multi-stage mold clamping force in the first and second mold clamping states when the first layer core material and the second layer intermediate material molten resin are injected and filled; it sets the mold opening amount of the multi-stage, the first-type opening amount when interposing the skin material to gold in the mold, the space decorative layer damaged between the said surface skin material and the mold can be elastic recovery a mold clamping condition setting unit for setting input and a second type opening amount to gaps ensuring,
A temperature condition input unit for setting and inputting a temperature for switching the mold clamping control state within a temperature range indicating the rubbery elasticity of the skin material decoration layer;
Compare the temperature monitor unit that monitors the surface temperature of the decorative material layer or the surface of the second layer intermediate resin during molding with the signal from the temperature monitor unit and the set value of the temperature condition input unit to the mold clamping control unit A comparison control unit that generates a timing signal for switching from the second mold clamping state to the second mold opening amount , a mold opening amount detection unit that detects the mold opening amount,
A resin multilayer molding apparatus comprising: a pressure detection unit that detects a mold clamping force; and a mold clamping control unit that controls a mold clamping mechanism based on signals from a comparison control unit and a mold clamping condition setting unit.

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