JP4757611B2 - Molded body molding method - Google Patents

Description

  The present invention relates to a method for forming a molded body.

  In recent years, for example, in order to support and fix a vehicle windshield on the inner surface of a vehicle body, a technology for integrally molding a resin molded body made of polypropylene or the like on the surface opposite to the cabin interior (glass outer surface) Has been developed. In a mold used for such an injection molding apparatus, a cavity having an opening to the outside is formed below the communication port with the nozzle. Then, the molten resin is introduced into the cavity from the nozzle through the communication port and injection molded into the resin molded body, and the closed surface of the glass (molded article) pressed and arranged to close the opening of the cavity from below. A part of the molten resin is led out from the opening to the outer surface (see Patent Document 1). In addition, such a technology is used to support and fix a vehicle interior panel material (molded article) composed of a resin board, a kenaf board, or the like on the inner surface of the vehicle body. It is also used when a support member (resin molded body) such as a resin bracket is integrally formed on the surface (back surface of the panel material).

Japanese Patent No. 3458468

  Since the technique as described in Patent Document 1 can directly and integrally form a resin molded body on a windshield or interior panel material that is a molded object, it is compared with the case where it is pasted with an adhesive or the like. Working time can be reduced. However, for example, in the case of an interior panel material made of resin, kenaf, or the like, the interior panel material is damaged (for example, cracks) or plastically deformed (for example, by a shrinking action when the molten resin that is a molding material is cooled and solidified) Bending (warping) may occur.

  An object of the present invention is to provide a molding method of a molded body that can be applied to various moldings by preventing damage, plastic deformation, etc. of the molding based on the shrinkage action when the molding material cools and solidifies. It is in.

Means for Solving the Problems and Effects of the Invention

In order to solve the above problems, a molding method of a molded body according to the present invention is as follows.
Using a molding die in which a cavity having an opening to the outside is formed in addition to the communication port with the nozzle, the molten elastomer is introduced from the nozzle into the cavity through the communication port and molded into a molded body. In this case, the molten elastomer is led out from the opening to the closing surface of the molding to be arranged so as to close the opening of the cavity, and cooled and solidified on the closing surface of the molding. A molding method comprising an elastomer which is a fixed part bonded and integrated with at least the closed surface ,
When the melted elastomer led to the opening of the cavity is cooled and solidified on the closed surface of the molding, the contraction stress generated inside by contraction is less than the bending rigidity of the molding. As a result, it is stretched by its own rubbery elasticity, and when solidified by being cooled to room temperature, it is bonded and integrated along the closed surface of the molding while maintaining the stretched state It becomes a part .

In addition, when performing the molding method of the molded body by injection molding,
By using a molding die in which a cavity having an opening to the outside is formed below the communication port with the nozzle by making the pair of split dies relatively close to each other in the horizontal direction to face each other, the communication from the nozzle When the molten elastomer is introduced into the cavity through the mouth and injection molded into the molded body, the molten elastomer is placed on the closed surface of the molding to be arranged so as to close the opening of the cavity from below. Is led out downward from the opening, and is cooled and solidified on the closed surface of the molding, so that the entire molded body is made of elastomer in a form including a fixing portion bonded and integrated with the closed surface. to configure.

  When the molten elastomer as the molding material cools and hardens, it shrinks, and at this time, shrinkage stress generated in all directions inside acts on the closing surface of the molding. However, according to these molding methods, by using an elastomer as a molding material, damage (for example, cracks) and plastic deformation (for example, bending (warping)) of a molded article due to shrinkage due to its rubbery elasticity. Etc. can be prevented. As a result, it can be applied to various molded articles.

  In other words, when the elastomer in the molten state led out to the opening of the cavity is cooled and solidified on the closed surface of the molding, the shrinkage stress generated inside by shrinkage is less than the bending rigidity of the molding. And stretched by its own rubbery elasticity. Further, when the elastomer is cooled to room temperature and solidification is completed, the elastomer is bonded and integrated along the closing surface of the molding while maintaining the stretched state to form a fixing portion. As described above, by using the rubber-like elasticity of the elastomer, the fixing portion (molded body) is bonded and integrated without causing warpage or the like even if the molding has a relatively small bending rigidity (bending resistance). be able to.

  Specifically, the volume elastic modulus at room temperature of the elastomer constituting the fixed part of the molded body is smaller than the bending elastic modulus at room temperature of the molding, and the fixed part is not covered at room temperature after cooling and solidification. While the stretched state is maintained along the closed surface of the molded product, the molded product maintains a state before the elastomer is led out. As a result, the molded object is less likely to bend (plastic deformation) regardless of the shrinkage effect when the molten elastomer is cooled and solidified, and the molded object remains in the state before the elastomer is released (ie, the initial state) even when the temperature returns to room temperature. ) Can be maintained. Here, “normal temperature” is set to 15 to 20 ° C. (288 to 293 K) according to JIS K0050 (general rules for chemical analysis methods) and JIS K0211 (analytical chemistry term (basic division)).

From the viewpoint of maintaining the strength of the molded body, the volume modulus of elasticity of the elastomer at room temperature is as close as possible to the bending modulus of elasticity of the molded article at room temperature as much as possible (that is, within a range in which the molded article does not undergo bending deformation). It is desirable. That is, when the bending elastic modulus at room temperature of the molding is B (for example, 1000 MPa (102.0 kg / mm ² )), the volume elastic modulus V of the elastomer at normal temperature is 0.5B ≦ V ≦ 0. The range of 9B (for example, 500-900 MPa (51.0-91.8 kg / mm < ² >)) is desirable. Here, when the volume modulus V of the elastomer at room temperature is less than 0.5 B, the strength of the molded body may be insufficient. On the other hand, when the volume modulus of elasticity V at room temperature of the elastomer exceeds 0.9B, bending deformation may occur in the molding due to variations in molding parameters.

  Also, the cavity opening is filled and closed by the fixing part when the molten elastomer is cooled to room temperature and solidification is completed, so that the molten elastomer does not protrude greatly outside the opening. Get better.

Furthermore, in order to solve the above-mentioned problem, the molding method according to the present invention uses a molding die in which a cavity having an opening to the outside is formed in addition to the communication port with the nozzle. When the molten elastomer is introduced into the cavity through the communication port and formed into a molded body, the molten elastomer is first introduced into the cavity from the nozzle through the communication port, and then from the nozzle. By introducing molten plastic into the cavity through the communication port, all or part of the initially introduced molten elastomer is led out to the opening, and arranged so as to close the opening of the cavity. Cooling and solidifying on the closed surface of the workpiece to be molded, at least the fixed part bonded and integrated with the closed surface is made of elastomer And wherein the Rukoto.
In this way, if a multi-material molding (also called multi-color molding) technique in which molten elastomer and molten plastic are sequentially (or alternately) introduced into a cavity and molded into a single molded body is used, the characteristics of each material can be obtained. Harmonized new compacts can be produced. Here, the first material introduced (injected) molten elastomer is led out to the opening to be a fixed part of the molded body, and the later introduced (injected) molten plastic is composed of two materials (or 2) constituting the main body of the molded body. Color) molding and the like can be performed. By forming the fixing portion with the elastomer, the plastic deformation of the molding can be prevented as described above, and the overall strength of the molded body can be increased by molding the main body portion with the plastic.

  In particular, in the case of injection molding, a complicated shape can be imparted to the molded body without causing an undercut or the like by relatively moving the pair of split molds substantially in the horizontal direction. Also, by providing the cavity opening downward, the molten elastomer can be led out (injected) to the closed surface, the contact between the opening and the closed surface, and the molten elastomer adhered to the closed surface in a short time. .

  Here, “elastomer” refers to a high molecular weight material that exhibits rubber-like elasticity (deforms when an external force is applied but returns to its original shape when an external force is removed) near normal temperature. “Plastic” refers to a polymer material that exhibits plasticity (a property that causes distortion without applying external force and deforms without breaking, and does not return to its original state even when external force is removed). (plastomer) ". Usually, synthetic rubber is classified as an elastomer, and synthetic resin is classified as a plastic (plastomer).

  As the elastomer, thermoplastic elastomers such as styrene, polyurethane, polyester, polyamide, fluorine, vinyl chloride, polyolefin, polyisoprene, and polyethylene can be employed.

  On the other hand, for example, polypropylene can be used as the plastic. However, the present invention is not limited thereto, and synthetic resins such as engineering plastics such as polyacetal, polyamide, polycarbonate, modified polyphenylene oxide, polybutylene terephthalate, polysulfone, polyphenylene sulfide, and other general-purpose plastics can be used.

  A representative example of the “molding die” according to the present invention is an injection molding die comprising a pair of split dies, one of which is fixed and the other is movable. However, the “mold” includes a mold used in a molding method other than injection molding (for example, compression molding, transfer molding, cast molding, etc.).

  By the way, when the molded body is integrated by adhering to the closing surface of the molding by the fixing portion on the base end side, and has a working portion for fixing the molding to another member on the distal end side, The working part and the working part can be formed almost simultaneously, and the working time is further shortened.

  Further, even if the object to be molded is a flat plate-shaped member made of a non-metallic organic material such as resin or kenaf and having a closed surface formed as a flat surface, plastic deformation such as bending (warping) is caused. It is hard to wake up. Therefore, for example, when the vehicle interior panel material is implemented as a molded article, a support member such as an elastomer bracket on the back side without generating wrinkles or the like due to warpage on the surface side of the panel material that becomes the design surface (Molded body) can be integrally molded.

  Therefore, the following vehicle interior material unit including the vehicle interior panel material and the molded body can be realized by using the molding method described above.

As a first aspect of the vehicle interior material unit,
A vehicle interior panel material that is a flat plate-like member made of a non-metallic organic material such as resin or kenaf and having a closed surface formed on a flat surface, and the vehicle interior by a fixing portion on the base end side A vehicle interior material unit comprising: a molded body having an action part for fixing the vehicle interior panel material to the vehicle body on the front end side;
Using a molding die in which a cavity having an opening to the outside is formed in addition to the communication port with the nozzle, the molten elastomer is introduced from the nozzle into the cavity through the communication port and molded into the molded body. In this case, the molten elastomer is led out from the opening to the closing surface of the vehicle interior panel material arranged so as to close the opening of the cavity, and on the closing surface of the vehicle interior panel material. By cooling and solidifying, at least the fixed portion bonded and integrated with the closed surface can be made of an elastomer.

As a second aspect of the vehicle interior material unit,
A vehicle interior panel material that is a flat plate-like member made of a non-metallic organic material such as resin or kenaf and having a closed surface formed on a flat surface, and the vehicle interior by a fixing portion on the base end side A vehicle interior material unit comprising: a molded body having an action part for fixing the vehicle interior panel material to the vehicle body on the front end side;
By using a molding die in which a cavity having an opening to the outside is formed below the communication port with the nozzle by making the pair of split dies relatively close to each other in the horizontal direction to face each other, the communication from the nozzle When the molten elastomer is introduced into the cavity through the mouth and injection molded into the molded body, the opening of the cavity is disposed on the closing surface of the vehicle interior panel material arranged to close the opening from below. The molten elastomer is led out downward from the opening, and cooled and solidified on the closed surface of the vehicle interior panel material, thereby including the fixed portion bonded and integrated with the closed surface. The whole body can be composed of an elastomer.

  Thus, the vehicle interior panel material can constitute a base material such as a dashboard or an instrument panel, and the molded body can constitute a mounting bracket or the like that supports and fixes the vehicle interior panel material to the vehicle body. As described above, since the occurrence of cracks and bends in the vehicle interior panel material is prevented, wrinkles and the like hardly occur on the design surface (the surface on the indoor side opposite to the closed surface).

Example 1
Next, embodiments of the present invention will be described with reference to examples shown in the drawings. FIG. 1 is a front view showing an example of an injection molding apparatus for carrying out the molding method of the present invention. This injection molding apparatus 100 manufactures a vehicle interior material unit 1 (see FIG. 3) and the like, which will be described later, using an injection mold 10 (molding mold; hereinafter simply referred to as a mold). The mold 10 includes a pair of split molds including a fixed mold 11 (first split mold) and a movable mold 12 (second split mold). When the movable mold 12 is moved to the fixed mold 11 side, a cavity 13 is formed. The A molten elastomer (for example, acrylonitrile-butadiene rubber (NBR system)) is injected into the cavity 13 by an injection device 20 having a screw (not shown). The cavity 13 has a communication port 13b communicating with the tip nozzle 21 of the injection device 20 and an opening 13a to the outside formed below the communication port 13b. Below the mold 10, the vehicle interior panel material 2 (molded product) is disposed so as to close the opening 13 a with the upper surface 2 a (closed surface).

  In the injection molding apparatus 100, in addition to the mold 10 and the injection apparatus 20, a mold moving mechanism 30 that moves the movable mold 12 in a substantially horizontal direction and the vehicle interior panel material 2 are moved upward, and an upper surface 2a thereof. Is provided with an interior panel material moving mechanism 40 (molding object moving mechanism) that presses (contacts) the opening 13a with the opening 13a. Reference numeral 41 denotes a buffer member (cushion material) that is attached to the distal end portion of the operating member 42 of the interior panel material moving mechanism 40 and reduces an impact when pressing the interior panel material 2 and the mold 10. Reference numeral 43 denotes a buffer member (cushion material) that is attached to a mold fixing member 44 fixed to the interior panel material moving mechanism 40 and protects the end surface of the interior panel material 2.

  In such an injection molding apparatus 100, when the molten elastomer is injected (introduced) from the nozzle 21 of the injection apparatus 20 into the cavity 13 through the communication port 13b, the molded part 3 reflecting the shape of the cavity 13 (see FIG. 3). Molded body) is molded. At that time, when a part of the molten elastomer is led out downward from the opening 13a to the upper surface 2a of the interior panel material 2, the molten elastomer in the opening 13a is cooled and solidified on the upper surface 2a and bonded and integrated with the upper surface 2a. It becomes the fixing | fixed part 3a (refer FIG. 3) when forming.

  Next, an example of an injection molding method for manufacturing the interior material unit 1 by injection molding the molded part 3 using the injection molding apparatus 100 will be described with reference to FIG.

(1) Interior panel material movement process (Fig. 2 (a), (b))
The interior panel member moving mechanism 40 (see FIG. 1) moves the interior panel member 2 upward (moves the mold 10 relatively downward (in the direction of the arrow in FIG. 2 (b))), and its upper surface 2a is moved to the mold 10. Press (contact) the (opening 13a) and hold it.

(2) Mold moving process (FIG. 2 (c))
After completion of the previous process (or almost simultaneously with the previous process), the movable mold 12 is moved in a substantially horizontal direction by the mold moving mechanism 30 (see FIG. 1) to form the cavity 13 between the opposed fixed molds 11. To do. At this time, the opening 13 a of the cavity 13 is closed (closed) by the upper surface 2 a of the interior panel material 2.

(3) Elastomer introduction and adhesion process (Fig. 2 (d))
A molten elastomer M such as acrylonitrile-butadiene rubber (NBR system) is injected into the cavity 13 from the nozzle 21 of the injection device 20 through the communication port 13b. At this time, since the opening portion 13a is closed by the upper surface 2a, a part of the molten elastomer M (that is, the one first injected from the nozzle 21) fills the opening portion 13a and spreads over the upper surface 2a for cooling / cooling. By solidifying, the fixed portion 3a bonded and integrated with the upper surface 2a of the interior panel material 2 is obtained. It should be noted that the amount of elastomer delivered to the opening 13a by adjusting the injection pressure or the like so that the molten elastomer M in the opening 13a does not protrude greatly outside the opening 13a when it becomes the fixed portion 3a by cooling and solidification. It is desirable to adjust.

  Through the above steps, the interior material unit 1 in which the molded part 3 is integrated with the upper surface 2a of the interior panel material 2 is completed (see FIGS. 2D and 3). When the interior panel material moving mechanism 40 and the mold moving mechanism 30 (see FIG. 1) are driven in the opposite directions, the interior material unit 1 can be taken out.

  In such an injection molding method, the molten elastomer M, which is a molding material, contracts when it cools and hardens, and the contraction stress generated in all directions at this time acts on the upper surface 2a of the interior panel material 2 (arrow in FIG. 3). reference). However, by using an elastomer as the molding material, it is possible to prevent damage (for example, cracks) and plastic deformation (for example, bending (warping)) of the interior panel material 2 based on the contraction action due to its rubber-like elasticity.

  More specifically, when the molten elastomer M led out and filled in the opening 13a of the cavity 13 is cooled and solidified on the upper surface 2a of the interior panel material 2, the contraction stress generated inside due to the contraction is applied to the interior panel material. 2 below the bending rigidity (bending resistance) of 2 and stretched by its own rubbery elasticity. Further, when the molten elastomer M is cooled to room temperature and solidification is completed, the molten elastomer M is bonded and integrated along the upper surface 2a of the interior panel material 2 while maintaining the stretched state to form the fixing portion 3a (FIG. 2 ( d), see FIG. Thus, even when the interior panel material 2 has a relatively small bending rigidity (bending resistance) by utilizing the rubber-like elasticity of the elastomer, the fixed portion 3a (molded part 3) is bonded and integrated. It is difficult to cause plastic deformation such as bending and warping.

When the molten elastomer M is cooled and solidified and returned to room temperature, the volume elastic modulus V (for example, 700 MPa (71.4 kg / mm ² )) of the elastomer constituting the fixing portion 3a of the molded part 3 is set to the interior panel material 2. The bending elastic modulus B is smaller (V <B) than the bending elastic modulus B (for example, 1000 MPa (102.0 kg / mm ² )). Therefore, the adhering portion 3a maintains the extended state along the upper surface 2a of the interior panel material 2, while the interior panel material 2 maintains the initial state. As a result, the interior panel material 2 is less likely to bend, warp, etc. (plastic deformation) regardless of the shrinkage effect when the molten elastomer M is cooled and solidified. (Ie, the initial state) can be maintained.

  A structural example of the interior material unit 1 taken out from the injection molding apparatus 100 is shown in FIG. 3, and a usage example is shown in FIG. As shown in FIG. 3, the molded part 3 of the interior material unit 1 is integrally bonded to the upper surface 2a of the interior panel material 2 by the fixing portion 3a on the base end side, and the interior panel material 2 is connected to the other member on the distal end side. It has the action part 3b for fixing to (for example, vehicle body). On the other hand, the interior panel material 2 is a single-layer or multiple-layer (for example, two-layer) flat plate material made of resin, kenaf, or the like and having an upper surface 2a formed on a flat surface.

  As shown in FIG. 4, the interior material unit 1 is used as, for example, a dashboard (or an instrument panel) D that is supported and fixed to the inner surface of the vehicle body of the automobile C. Here, since the surface opposite to the upper surface 2 a of the interior panel material 2 is a design surface (front surface) inside the cabin, the upper surface 2 a is located on the back surface side of the interior panel material 2. Therefore, the interior panel material 2 constitutes the base material of the dashboard D, and the molded part 3 constitutes a mounting bracket that supports and fixes the interior panel material 2 to the vehicle body. As described above, since the occurrence of cracks and bends in the interior panel material 2 is prevented, wrinkles and the like hardly occur on the design surface (the surface on the cabin side opposite to the upper surface 2a).

(Modification 1)
Next, a modification of the injection molding method of FIG. 2 will be described. In this modification, two-material molding (two-color molding) can be performed in the elastomer introduction / adhesion step shown in FIG. Specifically, in FIG. 2D, first, a molten elastomer such as acrylonitrile-butadiene rubber (NBR type) is injected (introduced) into the cavity 13 from the nozzle 21 through the communication port 13b. Immediately thereafter, molten plastic such as polypropylene is injected (introduced) into the cavity 13 from the nozzle 21 through the communication port 13b, so that all or part of the initially injected molten elastomer is led out to the opening 13a. To fill. The molten elastomer led out and filled in the opening 13a in this way is bonded and integrated along the upper surface 2a of the interior panel material 2 through the same process as in the first embodiment, and becomes the fixed portion 3a.

  According to this modification, the molten elastomer injected first is led out to the opening 13 a to be the fixing portion 3 a of the molded part 3, and the molten plastic injected later is configured in the main body of the molded part 3. As a result, it is possible to prevent plastic deformation (bending, warping, etc.) of the interior panel material 2 to which the fixing portion 3a is bonded and integrated, while increasing the overall strength of the molded part 3.

For example, when the flexural modulus B of the interior panel material 2 is 1000 MPa (102.0 kg / mm ² )), the volume elastic modulus Ve of the elastomer is 500 MPa (51.0 kg / mm ² )), and the plastic bulk modulus Vp 1300 MPa (132.7 kg / mm ² )). This is because even if the volume elastic modulus Vp of the main body (made of plastic) of the molded part 3 is larger than the bending elastic modulus B of the interior panel material 2, the interior panel material 2 is not bent or warped. I mean. That is, if these elastic moduli are set so as to satisfy the relationship Ve <B <Vp, it is possible to easily achieve prevention of plastic deformation of the interior panel material 2 and improvement of the overall strength of the molded part 3. Therefore, by adopting two-material molding (two-color molding), the choices of the material constituting the interior panel material 2 and the molding material (elastomer and plastic) constituting the molded part 3 are greatly expanded.

(Example 2)
Next, another example of the injection molding method for manufacturing the interior material unit 1 by injection molding the molded part 3 using the above-described injection molding apparatus 100 (see FIG. 1) will be described with reference to FIG.

(1) Mold placement process (FIGS. 5A and 5B)
The movable mold 12 is moved substantially in the horizontal direction by the mold moving mechanism 30 (see FIG. 1), and the cavity 13 is formed between the opposed fixed mold 11. At this time, the opening 13a of the cavity 13 is at a position spaced upward from the upper surface 2a of the interior panel material 2, and is opened downward.

(2) Elastomer introduction process (FIG. 5C)
While the opening 13a of the cavity 13 is spaced from the upper surface 2a of the interior panel material 2, the melted elastomer M such as acrylonitrile-butadiene rubber (NBR system) or the like is passed from the nozzle 21 of the injection device 20 through the communication port 13b. It injects in. At this time, a part of the molten elastomer M (that is, the one first ejected from the nozzle 21) is led downward from the opening 13a and becomes an elastomer reservoir MB such as a ball shape or a water droplet shape, and the opening of the opening 13a. Adhere along the edge. In this step, the molten elastomer M in the elastomer reservoir MB is not solidified or is being solidified, and has not been cooled to room temperature. Therefore, the molten elastomer M in the cavity 13 is totally solidified or in the course of solidification, and has fluidity. It is desirable to adjust the injection pressure or the like so that the molten elastomer M in the elastomer reservoir MB does not fall on the upper surface 2a.

(3) Elastomer bonding process (FIG. 5 (d))
After the injection from the nozzle 21 is stopped (or almost simultaneously), the interior panel material 2 is moved upward by the interior panel material moving mechanism 40 (see FIG. 1) (the mold 10 is moved relatively downward (FIG. 5 (d) ) Moved in the direction of the arrow), and the mold 10 (upper surface 2a) is pressed (contacted) with the mold 10 (opening 13a) and held. At this time, with the pressing of the mold 10 and the interior panel material 2, the opening 13a is closed on the upper surface 2a, and the molten elastomer M of the elastomer reservoir MB spreads on the upper surface 2a to be cooled and solidified. It is bonded and integrated with the upper surface 2a of the interior panel material 2. That is, in this process, the molten elastomer M of the elastomer reservoir MB is bonded to the upper surface 2a by the residual heat, and when solidified by being cooled to room temperature, the bonded portion 3a is bonded and integrated with the upper surface 2a. The opening 13a is filled and closed. It should be noted that when the elastomer reservoir MB (molten elastomer M) in the opening 13a becomes the fixed portion 3a by cooling and solidification, the elastomer reservoir is adjusted by adjusting the injection pressure or the like so that it does not protrude greatly outside the opening 13a. It is desirable to adjust the amount of the derived elastomer of the part MB.

  Through the above steps, the interior material unit 1 in which the molded part 3 is integrated with the upper surface 2a of the interior panel material 2 is completed (see FIGS. 5D and 3). When the interior panel material moving mechanism 40 and the mold moving mechanism 30 (see FIG. 1) are driven in the opposite directions, the interior material unit 1 can be taken out.

  Also by such an injection molding method, as described in the first embodiment, the interior panel material 2 is bent and hardly undergoes plastic deformation such as warpage.

(Modification 2)
Next, a modification of the injection molding method of FIG. 5 will be described. In this modification, two-material molding (two-color molding) can be performed in the elastomer introduction process shown in FIG. Specifically, in FIG. 5C, first, a molten elastomer such as acrylonitrile-butadiene rubber (NBR system) is injected (introduced) into the cavity 13 from the nozzle 21 through the communication port 13b. Immediately thereafter, molten plastic such as polypropylene is injected (introduced) into the cavity 13 from the nozzle 21 through the communication port 13b. As a result, all or a part of the first injected molten elastomer is led downward from the opening 13a and becomes an elastomer reservoir MB having a ball shape or a water droplet shape and adheres along the opening edge of the opening 13a. The molten elastomer led out to the opening 13a in this way is bonded and integrated along the upper surface 2a of the interior panel material 2 through the same process as in the second embodiment, and becomes the fixed portion 3a.

  According to this modification, the molten elastomer injected first is led out to the opening 13 a to be the fixing portion 3 a of the molded part 3, and the molten plastic injected later is configured in the main body of the molded part 3. As a result, it is possible to prevent plastic deformation (bending, warping, etc.) of the interior panel material 2 to which the fixing portion 3a is bonded and integrated, while increasing the overall strength of the molded part 3. With the adoption of two-material molding (two-color molding), the selection range of the material constituting the interior panel material 2 and the molding material (elastomer and plastic) constituting the molded part 3 is expanded as in the first modification. be able to.

(Example 3)
Next, still another example of the injection molding method for manufacturing the interior material unit 1 by injection molding the molded part 3 using the above-described injection molding apparatus 100 (see FIG. 1) will be described with reference to FIG.

(1) Interior panel material movement process (Fig. 6 (a), (b))
The interior panel material moving mechanism 40 (see FIG. 1) moves the interior panel material 2 upward (moves the mold 10 relatively downward (in the direction of the arrow in FIG. 6 (b))), and the upper surface 2a is moved to the mold 10. Press (contact) to hold.

(2) Elastomer introduction process (FIG. 6B)
A molten elastomer M such as acrylonitrile-butadiene rubber (NBR type) is injected from the nozzle 21 of the injection device 20 through the communication port 13b. At this time, the movable mold 12 is at a position separated from the fixed mold 11, and the cavity 13 for molding the molded part 3 is not yet formed. For this reason, after passing through the communication port 13b, the molten elastomer M falls as it is onto the upper surface 2a of the interior panel material 2 positioned below to form a mountain-shaped or plateau-shaped elastomer accumulation portion MC. Of course, at this stage, the molten elastomer M of the elastomer deposition part MC is not in contact with the inner wall of the movable mold 12 and the fixed mold 11 in which the cavity 13 is to be formed, and is solidified or is in the process of solidification, and is cooled to room temperature. Since it has not been done, it still has liquidity. In addition, since it injects in the state where the cavity 13 is not formed, the injection pressure can be set lower than normal (for example, 98 MPa (10 kg / mm ² )) (for example, 49 MPa (5 kg / mm ² )). .

(3) Mold moving process (FIG. 6 (c))
Immediately after the end of injection in the previous process (or prior to the end of injection), the movable mold 12 is moved in a substantially horizontal direction by the mold moving mechanism 30 (see FIG. 1), and the cavity 13 is formed between the opposed fixed mold 11. Form. At this time, the elastomer accumulation part MC on the upper surface 2a of the interior panel material 2 is pressed by the inner walls of the movable mold 12 and the fixed mold 11, and the molten elastomer M is filled in each part (including the opening 13a) in the cavity 13. .

(4) Elastomer bonding process (FIG. 6 (d))
The melted elastomer M filled in the opening 13a spreads on the upper surface 2a and cools and solidifies to become a fixed portion 3a bonded and integrated with the upper surface 2a of the interior panel material 2. In addition, it is desirable to adjust the injection amount in the elastomer introduction process so that the molten elastomer M in the opening 13a does not protrude greatly outside the opening 13a when it becomes the fixing portion 3a by cooling and solidification. .

  Through the above steps, the interior material unit 1 in which the molded part 3 is integrated with the upper surface 2a of the interior panel material 2 is completed (see FIG. 6D and FIG. 3). When the interior panel material moving mechanism 40 and the mold moving mechanism 30 (see FIG. 1) are driven in the opposite directions, the interior material unit 1 can be taken out.

  Also by such an injection molding method, as described in the first or second embodiment, the interior panel material 2 is bent and hardly undergoes plastic deformation such as warpage.

  In the above description, only injection molding has been described, but other molding methods (for example, compression molding, transfer molding, cast molding, etc.) can be employed. Further, a single mold 10 may be used instead of the pair of split molds 11 and 12.

The front view which shows an example of the injection molding apparatus for enforcing the shaping | molding method of this invention. Explanatory drawing which shows an example of the injection molding method which concerns on this invention. The perspective view of the interior material unit injection-molded by the method of FIG. The perspective view which shows the usage example of the interior material unit of FIG. Explanatory drawing which shows the other example of the injection molding method which concerns on this invention. Explanatory drawing which shows the further another example of the injection molding method which concerns on this invention.

Explanation of symbols

1 Vehicle interior material unit 2 Vehicle interior panel material (molded article; base material)
2a Top surface (blocking surface)
3 Molded parts (molded body; mounting bracket)
3a Adhering part 3b Action part 10 Mold (molding die; injection mold)
11 Fixed type (first division type)
12 Movable type (second division type)
13 Cavity 13a Opening 13b Communication Port 20 Injection Device 21 Nozzle 100 Injection Molding Device

Claims (7)

Using a molding die in which a cavity having an opening to the outside is formed in addition to the communication port with the nozzle, the molten elastomer is introduced from the nozzle into the cavity through the communication port and molded into a molded body. In this case, the molten elastomer is led out from the opening to the closing surface of the molding to be arranged so as to close the opening of the cavity, and cooled and solidified on the closing surface of the molding. , At least the fixing part bonded and integrated with the closing surface is made of an elastomer ,
When the melted elastomer led to the opening of the cavity is cooled and solidified on the closed surface of the molding, the contraction stress generated inside by contraction is less than the bending rigidity of the molding. As a result, it is stretched by its own rubbery elasticity, and when solidified by being cooled to room temperature, it is bonded and integrated along the closed surface of the molding while maintaining the stretched state A method for forming a molded body, wherein the molded body is a part . The volume elastic modulus at room temperature of the elastomer constituting the fixed part of the molded body is smaller than the bending elastic modulus at room temperature of the molding,
At room temperature after cooling and solidifying, the fixing unit while maintaining the extended state along the closing surface of the object to be molded, according the to claim 1 the molded product is to maintain the state before the elastomer derived Molding method of the molded body. Using a molding die in which a cavity having an opening to the outside is formed in addition to the communication port with the nozzle, the molten elastomer is introduced from the nozzle into the cavity through the communication port and molded into a molded body. In this case, the molten elastomer is first introduced into the cavity from the nozzle through the communication port, and then the molten plastic is introduced into the cavity from the nozzle through the communication port. By introducing all or a part of the introduced molten elastomer into the opening , and cooling and solidifying on the closing surface of the molding disposed so as to close the opening of the cavity, at least the closing surface A method for forming a molded body, characterized in that an adhering portion that is bonded and integrated with an elastomer is made of an elastomer. The method for molding a molded body according to any one of claims 1 to 3 , wherein the opening portion of the cavity is filled and closed by the fixing portion when the molten elastomer is cooled to room temperature and solidification is completed. . Wherein the elastomer is styrene, polyurethane, polyester, polyamide, fluorine-based, vinyl chloride, polyolefin, polyisoprene, claims 1 is a thermoplastic elastomer of polyethylene or the like to any one of 4 The molding method of the molded object of description. The molded body is integrally bonded to the closing surface of the molding by the fixing portion on the base end side, and has an action portion for fixing the molding to another member on the distal end side. Item 6. A method for molding a molded article according to any one of Items 1 to 5 . Wherein the molded product, the resin is composed of non-metallic organic material such as kenaf, and the blocking surface according to any one of claims 1 to 6 is a flat plate-shaped member formed on the flat surface Molding method of the molded article.

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