JPS6369611A - Molding device for synthetic resin molded form - Google Patents

Abstract

PURPOSE:To uniform the thickness of the layer of a molding surface, by a method wherein a movable mold member, provided in one part of a mold for molding the molding surface, is advanced and retreated. CONSTITUTION:A female mold 2 is moved upward by the elevating operation of an elevating device whereby a gap of 3-4mm is formed between the base body B of a molded form, molded already in a cavity 3, and a male mold 1. At this time, a movable mold member 4, annexed to the female mold 2, is retreated by 3-4mm to an imaginary line on a diagram by the contracting operation of a hydraulic pressure cylinder 5 and the extending operation of the hydraulic pressure cylinder 11. Then, a second synthetic resin molding material is injected to fill a gap between both molding surfaces 1a and 4a corresponding to the flange (a1) of a molded form. Thereafter, the female mold 2 is descended to clamp the molds and, at the same time, the movable mold member 4 is advanced to a full line on the diagram by the extending operation of the hydraulic pressure cylinder 5 and the contracting operation of the hydraulic pressure cylinder 11. Finally, the molds are pressurized and heated whereby the molded form A, in which the second synthetic resin is coated on the upper surface of the base body B of the molded form, may be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a molding apparatus for molding a multilayer molded product made of synthetic resin.

(Prior art) Conventionally, in a method of molding a synthetic resin laminate having a laminated surface layer, a first synthetic resin, which becomes the base of the laminate, is placed in the cavity eye of a mold. Generally, a molded product base is molded by filling a resin molding material and solidifying it, and then a second synthetic resin molding material is applied to the molded product base. It is being done.

However, when molding a synthetic resin laminate using this method, if air bubbles are exposed on the surface of the molded product base during the molding step of the molded product base, the air bubbles will be exposed to the second synthetic resin molded product that will be coated later. The material 4' is covered and sealed by the material 4', and the gas in the sealed bubble expands due to the thermal action during the formation of the surface layer of the second synthetic resin molding material, and the bubble is exposed again in the surface layer. Therefore, there was a problem in that it was difficult to finish the surface of the laminate product smoothly. In particular, in the case of a multilayer molded product, the pore diameter of the bubbles exposed on the surface of the laminate increases in proportion to the increase in the number of layers, making the bubbles very noticeable and unfavorable in terms of appearance.

Therefore, as a molding method to solve these problems,
For example, as disclosed in Equity 11i1 (59-23552@publication), the cavity formed between the mating surfaces of the male mold and the female mold is filled with a first synthetic resin molding material to preform the molded product base. After that, the female mold is moved away from the male mold, and the gap formed between the molded product base and the female mold in the cavity is filled with a second synthetic resin molding material, thereby molding the molded product. A so-called in-mold coating method is known in which a coating layer of a second synthetic resin molding material is laminated on a substrate.According to this method, the filling pressure when filling the second synthetic resin molding material or The second synthetic resin molding material is filled into the air bubbles exposed on the molded product base by the compression pressure of the mold (1!), thereby making it possible to mold a multilayer molded product with no air bubbles exposed on the surface layer.

(Problem to be solved by the invention) However, when molding a synthetic resin molded product having a flange portion by the above-mentioned in-mold coating method, the molding surface portion corresponding to the flange portion of the male mold and female molded product is Since each is formed on a molding surface substantially along the mold opening direction, after filling the first synthetic resin molding material and molding the molded article base as described above, the second synthetic resin molding material as a surface layer is applied. Even if the female mold is moved away from the male mold for filling, the gap between the two molding surfaces corresponding to the molded product flange becomes narrower than the gaps between the other molding surfaces, and as a result, A synthetic resin molded product filled with the second synthetic resin molding material has a problem in that the surface layer of the flange portion is necessarily thinner than other portions.

For this reason, it is conceivable to apply a treatment agent such as a second synthetic resin molding material separately to the flange part of the molded product in post-processing to compensate for the lack of layer thickness. There is a difference in level at the boundary with the part, and it is necessary to scrape off this difference, which takes extra time and trouble.
Moreover, traces remain after being scraped off, which is undesirable in terms of appearance.

The present invention has been made in view of the above, and its purpose is to make a mold part having a molding surface part substantially along the mold opening direction corresponding to the I-shaped molded product flange part movable. By filling the first synthetic resin molding material and preforming the molded article base, the direction in which one of the male mold and the female mold is temporarily left in order to fill the second synthetic resin molding material as a surface layer. Even if the molded product is moved to a second position, the gap between the two molding surface parts corresponding to the molded product flange part and the gap between the other molding surface parts can be made equal to each other.
There is no need to apply a treatment agent such as a synthetic resin molding material to the flange portion of the molded product, and the thickness of the surface layer made of the second synthetic resin molding material of the synthetic resin molded product can be easily changed over the entire surface layer. and to ensure uniformity. Also,
By doing as described above, it is possible to increase the degree of freedom of molding.

(Means for Solving the Problems) In order to achieve the above object, the solving means of the present invention provides a first
After preforming the molded product base by filling it with a synthetic resin molding material, move either one of the male mold or the female mold in the direction away from the molded product base to form a molded product base in the cavity between the molded product base and the female mold. By filling the gap formed by the second synthetic resin molding material, a synthetic resin molded product having a flange portion in which a coating layer of the second synthetic resin molding material is laminated on the molded product base is molded. In this case, a mold portion having a molding surface portion substantially along the mold opening direction corresponding to the molded product flange portion of the female mold is coated with at least a second synthetic resin after molding the molded product base. It is constituted by a movable mold member that moves backward when filling the molding material and moves forward after filling the second synthetic resin molding material.

With the above configuration, in the present invention, the male type and! After preforming the molded product base by filling the first synthetic resin molding material into the cavity formed between the mating surfaces with the mold Il, at least when filling the second synthetic resin molding material, the M-shaped molded product 7
The molding surface portion, which corresponds to the flange portion and extends substantially along the mold opening direction, is retracted.

From this, the gap between both molding surface parts corresponding to the flange part of the molded product 7 is made equal to the gap between the other molding surface parts, and after that, after filling the cavity with the second synthetic resin molding material, By moving the molding surface portion roughly along the mold opening direction corresponding to the molded product flange portion forward with the mold clamping operation, the layer thickness of the surface layer made of the second synthetic resin molding material of the synthetic resin molded product is ensured throughout. This will result in uniformity.

In addition, since the gap between the two molding surfaces corresponding to the flange portion of the molded product 7 and the gaps between the other molding surfaces are made equal as described above, a treatment agent such as a second synthetic resin molding material is separately applied to the molded product. There is no need to adopt the extra work step of applying the coating to the seven run portions of the molded article, and therefore the thickness of the surface layer of the molded article can be easily made uniform over the entire surface layer. In general, the degree of freedom in molding will be increased.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a synthetic resin molding device according to an embodiment of the present invention, in which 1 is a male mold as a lower mold supported on the upper surface of a fixed plate (not shown), and 2 is a male mold as a lower mold supported on the lower surface of a movable plate (not shown). , a female mold as an upper mold disposed above the male mold 1 so as to be movable up and down by the operation of a lifting device (not shown),
A cavity 3 corresponding to the shape of the synthetic resin molded article A to be molded is formed between the mating surfaces of the male die 1 and the female die 2 in the clamped state. A die of an injection molding device (not shown) is arranged on the side surface of the female mold 2, and the nozzle of the die is communicated with the cavity 3 through a launch, and the synthetic resin injected by the operation of the injection molding device is The material is injected and filled into the cavity 3.

In addition, the male mold 1 and the H mold 2 each have molding surface portions 1a and 4a formed on the peripheral edge of the cavity 3 in a vertical plane substantially along the mold opening direction, and both molding surface portions 1a, The flange portion a1 of the synthetic resin molded product A is formed using the gaps of 48 to 48.

As shown in enlarged detail in FIG. 2, the mold part having one of the image molding surface parts 1a and 4a, which has the female mold side molding surface part 4a, is constructed separately from the female mold 2, and is separate from the female mold 2. It is constituted by a rectangular parallelepiped-shaped movable mold member 4 that is openably disposed in a circumferential groove 2a recessed in the inner circumferential surface. A pair of first fluid pressure cylinders 5 arranged at a predetermined interval on the outside of the mold 2
The piston rods 5a each extend horizontally into the circumferential groove 2a of .degree.5 (as shown in FIG. 4).

It is connected to the tip of 5a via a shaft 6.6.

Further, on the lower surface of the circumferential groove 2a of the female mold 2, a plurality of guide rails 7.7. ... (only one is shown in the figure) are arranged at predetermined intervals in the longitudinal direction of the movable mold member 4, while the guide rails 7.
7. At the positions corresponding to..., guide grooves 4b, 4b,
... (only one is shown in the figure) is formed, and the movable member 4 is moved by the guide rails 7, 7, . It is guided by ... and can move forward and backward in the left and right directions in the figure.

Roughly speaking, a pair of horizontally extending stopper members 8, 8 are protruded from the upper and lower sides of the opposite side of the molding surface portion 4a of the movable mold member 4 at a predetermined interval at an appropriate number of locations in the longitudinal direction. The members 8, 8 are connected to both the first fluid pressure cylinders 5,
5, when the female mold 2 is extended, it engages with stopper blocks 9, 9 disposed on the upper and lower surfaces of the circumferential groove 2a of the female mold 2, corresponding to the side stopper members 8, 8, respectively. It restricts the movement (rightward in the figure) and prevents it from moving any further. The molding surface portion 4a of the movable mold member 4 is formed after the molded product base B of the synthetic resin molded product A is preformed by the expansion operation of each of the first fluid pressure cylinders 5, and before filling the synthetic resin QH molding material in the rear cylinder 2. When the female mold 2 is moved back by a slight distance, e.g. 3 to 4 m, the gap between the two molding surfaces 1a and 48 is made equal to the gap between the other parts, and the second synthetic resin molding material is filled. Later, it is moved forward in synchronization with the mold clamping by the female mold 2,
A synthetic resin molded article A having a coating layer C made of a hardened or solidified second synthetic resin molding material on the surface of the molded article base 8 is molded.

Further, the piston rod 5 of each first fluid pressure cylinder 5 is
At the tip of a, as shown in enlarged detail in FIG.
, 5b are bridge-connected with connecting pins 10 which are slidably inserted into the rear ends of the respective shafts 6 connected to the movable member 4 by means of spline coupling.
is movable in its longitudinal direction. Further, one end surface of the movable member 4 is connected to the tip of a piston rod 11a of another second fluid pressure cylinder 11, as shown in FIG.

The four movable members 4 configured in this manner
,4. ... is a movable mold part v adjacent to each other end face.
They are arranged so as to surround the cavity 3 on the four sides of the circumferential groove 2a of the female die 2 so as to abut against the side surface of one end of the cylinder I4, and when the first fluid pressure cylinders 5 are extended, each of the above-mentioned By contracting the second fluid pressure cylinder 11, each of the movable members 4 is moved from the state shown by the imaginary line in FIG. 4 to the state shown by the solid line, while each of the first fluid pressure cylinders 5 During the contraction operation, each of the second fluid pressure cylinders 11 is extended in the opposite manner to the above, thereby moving each of the movable members 4 from the state shown by the solid line in FIG. 4 to the state shown by the imaginary line. Therefore, each of the movable members 4 is always brought into contact with the four corners of the hinge 3 so that no gaps are formed.

When molding is performed using the molded product apparatus of this embodiment,
There are two types of molding materials: a first synthetic resin molding material that forms the molded product base B as an inner layer, and a second synthetic resin molding material that forms a coating layer C as a surface layer on the molded product base B. The first synthetic resin molding material is, for example, a sheet so-called sheet mold compound (SMC) in which a glass mat or glass fiber is impregnated with polyester and the curing reaction has proceeded halfway. As the material, for example, urethane resin in a d-molten state is used. Then, the first synthetic resin molding material is pressurized and filled into the cavity 3 by the female mold 2 which is placed on the upper surface of the male mold 1 and moved downward by the lowering operation of the lifting device, and is then reacted and cured by the mold temperature. The second synthetic resin molding material is preformed to form the molded product base B by being squeezed.
After molding, by moving the female mold 2 in a direction away from the male mold 1 (upward) by the lifting operation of the lifting device,
The gap formed between the molded product base B and the Ti mold 2 in the cavity 3 is injected from the die of the injection molding device through the runner, and a coating layer is formed as a surface layer on the molded product base B. Multiply C.

form a layer.

Next, to explain the molding procedure, first, while the female mold 2 is moved upward by the lifting operation of the lifting device, the male mold 1
A first synthetic resin molding material (SMC) is placed on the upper surface, and then the female mold 2 is moved downward by the lowering operation of the lifting device and the mold is clamped, thereby placing the first synthetic resin molding material into the cavity. 3. Pressurize and fill. At this time, each movable member 4 is moved forward as shown by the solid line in FIG. 4 by the extension action of each first fluid pressure cylinder 5 and the contraction action of each second fluid pressure cylinder 11. And the above first
The synthetic resin molding material is reacted and cured at the mold temperatures of the male mold 1 and female mold 2, and a molded article base A is preformed.

Next, by moving the female mold 2 upward by the lifting operation of the lifting device, a gap of 3 to 4# is formed between the molded product base B in the cavity 3 and the female mold 2, and at the same time By moving each movable mold member 4 backward by 3 to 4M as shown by the imaginary line in FIG. 4 by the contraction operation of each first fluid pressure cylinder 5 and the extension operation of each second fluid pressure cylinder 11, The gap between the box molding surface parts 1a and 4a corresponding to part a1 is made equal to the gap between the other molding surface parts (), and the second synthetic resin molding material is injected into this gap from the goo of the injection molding device via the runner. Fill.

Thereafter, the female mold 2 is moved downward by the lowering operation of the lifting device and the mold is clamped, and at the same time, the movable mold members 4 are moved by the extension operation of each first fluid pressure cylinder 5 and each second fluid pressure cylinder 11. The second synthetic resin molding material and the molded product base B are compressed and completely molded at the mold temperatures of the male mold 1'8 and the female mold 2 by moving forward as shown by the solid line in FIG. After reaction curing, a synthetic resin molded article A having a coating layer C of a second synthetic resin molding material laminated on the upper surface of a molded article base B is placed in a mold.

As described above, in this embodiment, when the second synthetic resin molding material is injected and filled, the image molding surface portion 1 corresponding to the flange portion a1 of the molded product 7 is
8.48 gap and its 4. li! Since the gaps between the molding surface parts of the box molding surface part 1a are made equal (),
, 4a does not become narrow, and as a result, the second synthetic resin molded material is made of 1 to form a synthetic resin molded product.
It is possible to reliably uniformize the distribution of the coating layer C over the whole,
J: It is possible to form a nail into a synthetic resin molded product with the same layer thickness as the other parts without making the layer thickness of the flange part a insufficient. As a result, the degree of freedom of molding can be increased.

Further, as described above, due to the backward movement of the molding surface portion 4a of the female mold 2 along the opening direction corresponding to the molded product flange portion al, the gap between the box molding surface portions 1a and 4a corresponding to the molded product flange portion alkc is Since the gaps between the molding surfaces of 11 and 11 (l) are made equal, there is no need to separately apply a treatment agent such as a second synthetic resin molding material to the flange part a1, so this application step can be omitted. Then, the thickness of the coating layer C can be made uniform throughout the cylinder and reduced by 1!.

Thereafter, the female mold 2 is moved upward by the vertical operation of the lifting device, and the synthetic resin molded product Δ formed as shown in FIG.

J3, in the above embodiment, the timing of the backward movement of each movable mold member 4 after molding the molded product base B was set at the same time as the upward movement of the 1f mold 2; however, the timing is not limited to this. It is also possible to set the process to be performed at the exact moment when the second synthetic resin molded material is full after the back movement is completed.

In addition, in the above embodiment, the first synthetic resin molding material is 'U'.
Although SMC is used, the present invention is not limited to this. For example, it is also possible to inject the melted resin into the cavity 3 at the same time as the second synthetic resin molding material. The resin used for molding is not limited to thermosetting resin as in the above embodiments, but may also be thermoplastic resin.

Further, in the above embodiments, a two-layer synthetic resin molded product is shown, but a laminate having three or more layers may also be used.

(Effects of the Invention) As explained above, according to the present invention, the mold part having the molding surface part that is substantially cured in the mold opening direction corresponding to the flange part of the molded product of bad shape is made movable ( The mold part is retracted when at least one second synthetic resin molding material is filled after molding the molded article base, and is moved forward after filling the second synthetic resin molding material, so that the second synthetic resin molding material is filled. In some cases, the gap between the two molding surfaces corresponding to the flange of the molded product can be made equal to the gaps between the other molding surfaces, that is, the second synthetic resin molding material can be uniformly filled onto the molded layered body without running out. As a result, there is no need to separately apply a treatment agent such as a second synthetic resin molding material to the flange portion, and the thickness of the surface layer made of the second synthetic resin molding material of the synthetic resin molded product can be increased over the entire surface layer. can be easily and reliably made uniform. Moreover, this increases the degree of freedom in molding, and allows the use of resin as a product material to be expanded.

[Brief explanation of the drawing]

Fig. 1 is a front view of flying stones of a molded neck of a synthetic resin molded product according to an embodiment of the present invention, Fig. 2 is an enlarged longitudinal sectional front view showing the peripheral edge of the female mold, and Fig. 3 is a piston of a fluid pressure cylinder. FIG. 4 is an enlarged perspective view showing a connecting portion between the iron and the shaft on the movable member side, and is an explanatory diagram illustrating the arrangement and operation of the movable member. 1...male type, 2...female type, buttock...cavity, 4.
... Movable mold member, 4a... Molding surface portion, A... Synthetic resin molded product, al... Flange portion, B... Molded product base, C... Coating layer. Patent applicant: Mazda Motor Corporation
Before Rinjin 1) Hiroshi ゛Figure 3Figure 4

Claims (1)

[Claims] (1) After preforming a molded product base by filling the first synthetic resin molding material into the cavity formed between the mating surfaces of the male mold and the female mold, either one of the male mold and the female mold is pressed. The second synthetic resin molding material is placed on the molded product base by moving the second synthetic resin molding material in the direction away from the molded product base and filling the gap formed between the molded product base and the female mold in the cavity with the second synthetic resin molding material. In a molding apparatus for molding a synthetic resin molded product having a flange portion on which a coating layer is laminated, the molding die has a molding surface portion substantially along the mold opening direction corresponding to the female molded product flange portion. The synthetic resin molded article is characterized in that the part is constituted by a movable mold member that retreats at least when the second synthetic resin molding material is filled after the molded article base is molded, and moves forward after the second synthetic resin molding material is filled. molding equipment.