JPH0311633B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to an injection molding simultaneous transfer device that performs injection molding of a resin and simultaneously applies a decoration to the surface of a molded product by transfer.

(b) Prior art A device for painting the surface of a three-dimensional resin molded product having a raised portion on the periphery, such as a thin container for cosmetics, by transfer at the same time as molding is disclosed, for example, in JP-A-59-164147. There is a device described in .

According to this device, a transfer film is sent and positioned between a fixed mold and a movable mold for each molding cycle, and during the mold clamping operation, the transfer film is sandwiched between the protrusions and recesses of the fixed mold and movable mold. before it is
A film fixing device is provided for fixing the positioned transfer film at that position.

(C) Problems to be Solved by the Invention This conventional device is configured to first clamp the transfer film to one mold, and then join the two molds together (clamp the molds). However, before the mold clamping is completed, when the convex part of the male die pushes the transfer film into the concave part of the female mold, wrinkles occur in the transfer film, and these wrinkles are gripped by the joined mold when the mold clamping is completed. If injection molding is performed as is, wrinkles may be formed in the film at the rising portions of the molded product.

(d) Structure and operation for solving the problem The present invention was proposed in view of the above-mentioned drawbacks. The projections of the male mold are projected into the corresponding recesses of the female mold, and at this time, the projections push the corresponding portions of the transfer film into the recesses to form the film, and then injection molding is performed.

For this purpose, according to the present invention, the male mold is composed of two component parts that are movable relative to each other, and one of the two component parts has a through hole that corresponds to the recess of the female mold, and a through hole that corresponds to the recess of the female mold. A joining end surface surrounding the through hole and capable of being joined to the joining end surface in which the female-shaped recess is formed is provided, and the other of the two components is provided with a protrusion corresponding to the female-shaped recess, and this The convex portion is slidably fitted and inserted into the through hole of the one component, and the convex portion is configured to be retractable from the joint end surface of the one component, and the male mold and the female mold are in an open state. In this case, the convex part of the other component part is recessed and held from the joining end surface of the one component part, and after the male and female molds are clamped, the convex part of the other component part is joined to the one component part. It is characterized in that it is also provided with means for protruding from the end face.

After positioning the transfer film with respect to one mold (for example, the concave part of the female mold), the two female molds are joined (clamped) without the convex part of the male mold protruding from the joint end surface. After the transfer film is clamped and fixed between both jointed end surfaces, the convex part of the male mold is made to protrude from the joint surface and the clamped transfer film is pushed into the concave part of the female mold, and then injection molding and transfer are performed at the same time. Let's do it.

(e) Examples The illustrated embodiment will be described in detail below.

In the figure, A and B are molds that are relatively movable along the guide rod C. In the illustrated example, A is a female mold and B is a male mold, and the female mold A is a cylinder (not shown) relative to the male mold B. They can be joined and separated by suitable driving means such as. A recess 2 is formed in the joint end surface 1 of the female mold A facing the male mold B. The recess 2 has the required external shape of the molded product. Reference numeral 3 denotes a roll of transfer film F supported by the female mold A, and the film F fed out from this roll passes through a guide roller 4 supported by the female mold A and passes through a recess 2 along the joining end surface 1 of the female mold A. The film F, which has been extended across the top and transferred as will be described later, is wound onto a roll 6 via a guide roller 5 supported on the opposite side of the female die A. For controlling the feeding of the transfer film F and the positioning of the female die A with respect to the recess 2, a known suitable device, not shown, can be used.

The male mold B consists of two components: a fixed block 7 and a movable block 8. The fixed block 7 is fixed to a guide rod C, and a movable block 8 is arranged on the female mold A side of the fixed block 7, and the movable block 8 is movable on the guide rod C relative to the fixed block 7. Fixed block 7 is female type A
The movable block 8 has a convex portion 9 corresponding to the concave portion 2, and a through hole 10 into which the convex portion 9 is slidably fitted is bored.

11 is a compression spring interposed between the fixed block 7 and the movable block 8; 12 has one end fixed to the fixed block 7 and the other end a corresponding hole 13 in the movable block 8;
The compression spring 11 is wound and supported by a support pin slidably inserted into the support pin. Reference numeral 14 denotes a stopper provided on the fixed block 7, which defines the length by which the convex portion 9 of the fixed block 7 projects from the joint end surface 17 through the through hole 10 of the movable block 8, as will be described later. That is, when the movable block 8 of the male die B is pushed toward the fixed block 7 by the female die A against the compression spring 11 as will be described later, the convex portion 9 is removed from the through hole 10 of the movable block 8. It protrudes toward the recess 2 of the female mold A, but the movable block 8 is stopped by the stopper 14.
Once the movable block 8 hits the fixed block 7, the movable block 8 cannot approach the fixed block 7 any further, and therefore the convex portion 9 no longer approaches the fixed block 7.
protrusion is regulated.

Reference numeral 15 denotes a resin supply path bored in the male fixed block 7, and the injection nozzle 16 at the tip is connected to the end surface 18 of the convex portion 9.
The other end is connected to a suitable resin supply device (not shown).

O is an O-ring buried as close as possible to the periphery of the through hole 10 in the male joint end surface 17, and a part of the peripheral surface slightly protrudes from the joint end surface 17. The O-ring is made of a material with appropriate elasticity and an appropriate coefficient of friction against the film F, and after the mold is clamped, the male movable block 8 protrudes to prevent the film F from forming.
This helps prevent the film F from slipping during molding.

The transfer film F is made of a synthetic resin having the required heat resistance and extensibility, and characters and symbols to be transferred are printed in advance on each of a large number of sections arranged in a row in the length direction.

In the above configuration, the fixed block 7 of the male type B
The transfer film F is placed in a state in which the end surface 18 of the convex portion 9 does not protrude from the joint end surface 17 of the movable block 8.
After positioning the new compartment opposite the recess 2 of the female mold A (FIG. 1), the female mold A is moved toward the male mold B to the right in the figure. Eventually, the joint end surface 1 of the female mold A becomes the opposite joint end surface 17 of the movable block 8 of the male mold B.
When it hits the transfer film F between both end faces 1 and 17
are clamped (Fig. 2).

When the female mold A is further moved to the right in the figure, the movable block 8 of the male mold B moves to the right while holding the transfer film F between it and the female mold A and compressing the compression spring 11. I am forced to do it. In response to the movement of the movable block 8 to the right, the fixed block 7
The tip of the convex part 9 (the left end in the figure) protrudes leftward from the through hole 10 of the movable block 8, and presses and stretches the transfer film F into the concave part 2 of the female die A (Fig. 3). Eventually, the movable block 8 comes into contact with the stopper 14 of the fixed block 7 and stops.
In FIG. 3, for clarity of illustration, the film F is drawn away from the end surface 18 of the convex portion 9 of the male mold B rather than in close contact with it. Movable block 8 is stopper 14
When stopped at , the protruding end surface 18 of the convex portion 9 of the male mold B
The transfer film F is confined within a gap 19 between the inner surface of the recess 2 of the female mold A, and the thickness of this gap 19 is set in accordance with the thickness of the resin molded product.

Next, when resin is injected from the nozzle 16, the injected resin R presses the transfer film F against the inner surface of the female recess 2 and fills the gap 19, so that the characters, etc. on the transfer film F are transferred to the resin surface. Ru. When the molding transfer is completed, the female mold is moved in the opposite direction (to the left) and the transfer film is wound onto the roll 6, and the molded product is carried by the film and taken out from the recess 2, completing one molding cycle. .

According to the present invention, various modified embodiments other than the illustrated example are possible.

First, the male type may be movable instead of the female type,
Both molds may be movable. It is also possible to configure so that both the female concave part and the male convex part can be replaced with ones of different shapes, in which case the stopper 14
It is also possible to configure the length to be variable. The resin injection nozzle can also be made to open on the inner surface of the female mold recess. In this case, if the transfer surface of the transfer film is turned opposite to the illustrated example (to face the recess of the female mold), the transfer will be performed on the concave surface of the molded product. It is also possible to provide a mechanism for softening the transfer film with hot air before it is held between the molds.

The O-ring may be provided on the female joint end surface 1 instead of the male joint end surface 17, or may be provided oppositely or concentrically on both joint end surfaces.

(F) Effect As described above, according to the present invention, after the transfer film is sandwiched between the joint surfaces of the male die and the female die, the sandwiched film is pushed into the concave portion of the female die by the convex portion of the male die. This eliminates the inconvenience that occurs when injection molding is performed with both molds holding the wrinkles of the transfer film in their mouths, especially when the shape of the molded product has a rise, resulting in wrinkles in the film appearing on the molded product.
Further, there is no positional shift of the transfer film, and highly accurate transfer is possible. Furthermore, the male mold is configured by a component having a joint end surface that can be joined to the joint end surface of the female mold, and a component having a convex portion that can protrude and retract from the joint end surface of this component, and the mold is in an open state. In this method, the convex part is recessed from the joint end face and a means is provided to push the convex part into the recess of the female mold after mold clamping, so there is no need to add a special mechanism to press the film against the joint end face, and the structure is simple. becomes.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view showing a schematic configuration of an apparatus according to an embodiment of the present invention, FIGS. 2 and 3 are views similar to FIG. 1 but showing different operation stages, and FIGS. Figure 4 is an enlarged sectional view of the main part. A...female type, B...male type, C...guide rod,
O...O-ring, 2...Concave portion, 7...Fixed block, 8...Movable block, 9...Protrusion, 10...
Through hole.

Claims (1)

[Claims] 1. A male mold and a female mold for resin injection molding, a means for supporting the male mold and the female mold in a relatively movable manner, and a means for supplying and positioning a transfer film between the male mold and the female mold. a driving means for moving the female mold and the male mold relatively to sandwich the transfer film between the joined end surfaces of the two; and injecting resin into a molding space defined by the joined male mold and female mold. wherein the male die is composed of two component parts movable relative to each other, one of the two component parts has a through hole corresponding to the recess of the female mold, and a through hole corresponding to the recess of the female mold; A joining end surface surrounding the hole and capable of being joined to the joining end surface in which the female-shaped recess is formed is provided, and a protrusion corresponding to the female-shaped recess is provided on the other of the two components, and the protrusion The part is slidably fitted and inserted into the through hole of the one component, and the convex part is configured to be retractable from the joint end surface of the one component, and when the male mold and the female mold are in an open state. holds the convex portion of the other component part by recessing it from the joint end surface of the one component part, and after the male and female molds are clamped, the convex part of the other component part is inserted into the joint end surface of the one component part. An injection molding simultaneous transfer device characterized in that it is also provided with means for protruding from. 2. The injection molding simultaneous transfer device according to claim 1, wherein an O-ring is embedded as close as possible to the concave portion on the joining end surface of one or both of the male mold and the female mold.