JP2002079542A - Method and apparatus for injection-molding hollow article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mold a hollow article 9 having novel structure by a die slide method with the use of the first - third molds 1, 2, and 3. SOLUTION: After the first - third molds l, 2, and 3 are subjected to the first mold matching, and the half parts of the product 6, 7, and 8 are molded by primary injection, the molds 1, 2, and 3 are moved relatively to each other, the half parts 6, 7, and 8 are butted mutually, and the butt parts are bonded by secondary injection to mold the hollow article 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming various hollow molded articles, such as a turn signal, a side turn signal, a headlamp, a door mirror, and the like, which are attached to a vehicle when the vehicle is used as an example. It belongs to the technical field of injection molding method and molding apparatus for hollow products.

[0002]

2. Description of the Related Art At present, when a hollow molded body of this kind is formed, an injection molding apparatus of a die slide system is generally widely used. For example, Japanese Patent Application Laid-Open Nos. Sho 62-87315, Hei 7-144334, and Hei 11-162210 are known. A mold and a movable mold are provided, and each half of the hollow molded body is molded in the first injection step, and then the movable mold is moved so that the molded halves abut each other. In the process, these butted halves are bonded together.

[0003]

However, today, even in such a hollow molded article, there is a strong demand for design in addition to diversification of products, and therefore, the fixed mold and the movable mold as described above are required. The combination of a pair of dies alone cannot keep up with the demand for more complicated shapes.To deal with this, each of the dies themselves becomes more and more complicated, and the stability of the molding is increased. Problems such as being damaged remain, and there are problems to be solved by the present invention.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve these problems in view of the above situation, and has at least three adjacent dies in a series. A primary injection step in which at least three product halves are formed in each mold by matching each adjacent mold, and these molds are relatively moved to be formed in the primary injection step. A method of injection molding a hollow product, comprising a secondary injection step of bonding adjacent product halves in a state where the adjacent product halves are brought into contact with each other so as to abut each other. A primary molding means comprising at least three dies which are adjacent in a series, and forming a product half in each of the adjacent dies; Primary injection means for injecting each of the product halves, and mold moving means for relatively moving a mold so that the formed product halves are brought into contact with each other; And a secondary injection means for injecting a resin material in order to bond the product. With this configuration, three or more product halves can be molded in the primary injection process, and these product halves can be bonded in the secondary injection process, easily responding to the variety of hollow products. be able to. In these, when three molds are used, one of them is a fixed mold, the other two are movable molds, and the two movable molds are molded into the respective movable molds. The product half can be moved so as to abut the product half formed in the fixed mold, and when three molds are used, two of them are primary. In the injection step, a fixed mold set so that half of the product is formed at the same position, the other one is a fixed mold, and the one movable mold is a product molded into the movable mold. It is characterized in that the half is moved so as to abut the product half formed by the two fixed dies. In the latter case, although there are three molds, only one mold needs to be moved, and the structure can be simplified. Further, in this case, when a mold for alternately and simultaneously executing the primary injection step and the secondary injection step is formed in each mold, the primary and secondary injection steps can be performed simultaneously. Thus, workability can be improved. In this embodiment, an injection nozzle for performing the primary injection step and the secondary injection step alternately and simultaneously can be provided. Still further, in these products, the resin material injected in the secondary injection step is provided with a resin material injected in a secondary injection step from a butt portion of one product half to the other product half. If the flow path for flowing to the butting portion is formed, the secondary injection can be performed by one injection, even though two butting portions are formed. Can be measured. Further, in these, at least one mold may be characterized in that an insert mold for incorporating a preformed product half and performing a secondary injection step is formed. By doing so, it is possible to perform injection molding by incorporating a half-shaped product with a complicated shape that can not be molded only by combining two molds, and it is possible to manufacture a more complicated hollow tablet molded product Become. In addition, a primary injection step in which three molds adjacent to each other in a series are provided on the left and right sides, and the adjacent molds are matched with each other, and a half of the product is injection-molded. After the central mold is retreated from the mold matching area of the left and right molds with the parts left in the left and right molds, a mold moving step of matching so that the product halves remaining in the left and right molds abut each other, Injection molding method of a hollow product characterized by comprising a secondary injection step of performing injection molding to bond the product halves together, comprising three molds adjacent to each other in a series on the left and right, Primary mold-matching means for mold-matching each adjacent mold, primary injection means for injecting a resin material into the matched mold to form a product half, and The central mold is retracted and moved from the mold matching area of the left and right molds while leaving it in the mold,
And secondary mold matching means for performing mold matching so that the product halves remaining in the left and right molds abut each other, and secondary injection means for injecting a resin material so as to bond the butted product halves together. A hollow product injection molding apparatus characterized in that it is provided and configured. In this case, even a strong undercut product can be molded without any problem.

[0005]

Next, embodiments of the present invention will be described. First, the first embodiment shown in FIGS. 1 and 2 is provided with first to third dies 1, 2, and 3 arranged in a series on the left and right in FIG. age,
The first mold 1 does not move up and down in FIG. 1 but moves left and right with respect to the base (guide post) G of the molding machine. By attaching to the telescopic cylinder 4 provided to move left and right, a mold that moves up and down, left and right, and the third mold 3
Is a mold that moves up and down by a telescopic cylinder 5 provided on the base G without moving left and right. In other words, in consideration of the vertical movement of the mold in FIG. 1, a double die slide (double die movable) type in which the second and third molds 2 and 3 move is set.
Incidentally, the left and right movement of the dies 1, 2 and 3 may be performed by relatively moving the three dies to the left and right. However, as in the present embodiment, the remaining dies are based on one dies. By adopting a configuration in which the two dies are moved to the left and right, the structure can be simplified and implemented, which is convenient. For the left-right movement and the up-down movement of such a mold, a conventionally known technique can be employed as it is, and therefore, detailed description thereof will be omitted.

In the first embodiment, the female dies 1a and 3a are formed on the upper side of the first die 1 and the lower side of the third die 3 located on the left and right sides, respectively. Type 1, 3
The male molds 1b and 3b are formed at the center in the vertical direction (FIG. 1A). On the other hand, the left and right center second mold 2
As shown in FIG. 1 (B), when the molds 1 and 2 are moved left and right to perform the primary injection step and are matched, the male molds 2a and 2b fitted into the female molds 1a and 3a. Are formed up and down, and a female mold 2b into which the male molds 1b and 3b are fitted respectively from left and right is formed. In this way, primary injection is performed in a state where the primary molds are matched, and as a result, as shown in FIGS.
The product halves 6, 7, 8 are molded into 3 respectively. Next, the telescopic cylinders 4, 5 are contracted and the product halves 5, 6 formed in the second and third molds 2, 3 are adjusted to the height corresponding to the product half 4 of the first mold 1. After moving (Fig. 1 (D))
These molds 1, 2, and 3 are subjected to secondary mold matching (FIG. 1).
(E) Move left and right as much as possible. Thereafter, the product halves 6, 7, 8 are bonded by secondary injection, and the completed hollow article 9 is released (FIG. 1 (F)). In addition, the second mold 2
Is formed with a female mold 2c for fitting the male molds 1b and 3b respectively in the second injection step. In the present embodiment, if the product halves 6 and 8 are set to be located at target positions centering on the product halves 7, the third mold 3 is not a slide system but a rotary system. be able to.

Next, a concrete example of a mold for enabling the double die slide molding will be described in detail. As shown in FIGS.
2, 3 are formed with sprues 1d, 2e, 3d for guiding the resin material X injected from an injection nozzle (not shown) to the female molds 1a, 2c, 3a. The sprue 2e for performing the primary injection into the female mold 2c of the second mold 2, which is sandwiched between the left and right sides, is formed in the second mold 2 as before. However, the present invention is not limited to this. For example, it is also possible to form the first mold 1), and to attach an adhesive material to the abutting surfaces of the product halves 6 and 7, 7 and 8 which abut each other. Injection material 1 which is secondarily injected as
The filling chamber S for filling 0 is formed by the male molds 1e, 2f, 3e formed in the dies 1, 2, and 3, however, in the present embodiment, the first dies 1, 3 In the mold 3, male dies 1f and 3f for forming a communication path for communicating with the filling chamber S and the sprues 1d and 3d which are abutted and formed at the time of the secondary injection are formed. .

In the primary injection step shown in FIG.
The product halves 6, 7, 8 are formed by the resin material injected and filled from the sprues 1d, 2e, 3d. After the product halves 6, 7, 8 are formed in this way, the second and third dies 2, 3 are moved vertically with respect to the first dies 1 as shown in FIG. The respective product halves 6, 7 and 7, 8 are abutted against one another, whereby the aforementioned filling chamber S is formed.
Thereafter, the filling chamber S is filled with the resin material 10 which is to be secondarily injected from the sprues 1d and 3d and becomes an adhesive (FIG. 4), and the hollow article 9 is formed by demolding. By the way, the filling chamber S is
It is only necessary to fill the resin material 10 for bonding the adjacent product halves 6, 7, and 7, 8 with each other. It is formed in a groove shape only on the half part side, and the flat surface of the other half of the product can be configured to abut this groove part. When a groove is formed and the mold is matched for secondary injection, the L
The adhesive resin material 10 may not be embedded in the product as in the above-described embodiment, and may be formed between the groove and the mold. Although it is exposed on the outer surface of the product, if this is not a problem, it is a matter of course that such a configuration may be adopted. In addition, it goes without saying that the shapes of the molds formed in the molds 2, 3, and 4 are various types of mixed male and female according to the shape of the product to be molded.

In the embodiment of the present invention configured as described above, three product halves 6, 7, 8 are used in the primary injection process.
After that, the molds 2 and 3 are moved up and down to abut the adjacent semi-finished products, and then the bonding resin material 10 is placed in the filling chamber S formed on each of these mating surfaces. By injection, a hollow material 9 composed of three types of product halves 6, 7, 8 is formed. As a result, the product halves 6, 7, and 8 can be easily molded even if all the resin materials are different (including not only the materials themselves but also different colors, densities, etc.). As a result, it is possible to easily mold even a complicated shape or combination that could not be molded by the conventional die slide method. It is needless to say that the sprue runner formed in the first and second injection steps is removed during the step.

The present invention is not limited to the above-described embodiment. As the dies which move the die, the first and third dies 11 on the left and right sides of the second embodiment shown in FIG. 13
May be moved up and down by the expansion and contraction operation of the expansion and contraction cylinders 14 and 15. And also in this case, the female dies 11a,
13a and the male molds 11b, 13b, while the second mold 12 holds the female molds 11a, 13a, the male molds 11b, 13b.
The male molds 12a and 12b and the female mold 12c are formed to correspond to. In the present embodiment, the female dies 11a, 13a of the first and third dies 11, 13 are used in the first injection step.
a is set so as to be at the same vertical position. Then, in this case, the state shown in FIG.
The third molds 11 and 13 are moved left and right to perform primary mold matching, and the primary injection is performed in this mold matching state, and each product half 6,
After molding 7, 8 (FIG. 5 (B)), each mold 11, 1
The left and right dies 11, 13 are moved vertically (FIG. 5D), and the product halves 6, 7, 8 abut each other. The secondary injection is performed in the same manner as the secondary mold, and the mold is removed (FIG. 5E).
(F)), the hollow product 9 is molded, and the embodiment can be implemented in this manner.

When the two molds 11 and 13 are configured so that the vertical movement amounts of the two molds 11 and 13 with respect to the remaining molds 12 are the same as in this embodiment, as in the third embodiment shown in FIG. In addition, the telescopic cylinder 16 can be shared. In other words, in this apparatus, the auxiliary base 17 is configured to be moved up and down by the telescopic cylinder 16, and the dies 11 and 13 that move up and down are assembled to the base 17 so as to be able to move further left and right. Thus, although the double die slide method is used, the up and down movement of the molds 11 and 13 can be achieved by one telescopic cylinder 16.
Simplification of the structure can be achieved.

Next, a fourth embodiment will be described with reference to FIG. In this configuration, the first and third dies 18 and 20 on both the left and right sides are not moved up and down, but only the center second mold 19 is moved up and down via the telescopic cylinder 21. In other words, this is the reverse of the relationship of the relative movement in the second and third embodiments, and by doing so, the relative double die slide system is substantially achieved. Means that only one mold 19 needs to be moved up and down, and the structure can be further simplified. The first mold 18 has a female mold 18a and a male mold 18b, and the second mold 1
9 has a female mold 19a, male molds 19b and 19c, and a third mold 2
0 has a female mold 20a and a male mold 20b.

Next, a fifth embodiment shown in FIG. 8 will be described. The mold of this embodiment basically operates in the same manner as that of the fourth embodiment, and the same reference numerals are used for the same symbols for the drawer codes. In this case, in the first injection step, the second mold 1
The setting is such that the resin material is not injected into the fitting portion between the male die 19c of No. 9 and the female die 20a of the third die 20,
As a result, in the first injection step, the product halves 6, 7 are formed (FIGS. 8A to 8C). Next, before performing secondary mold matching, a semi-finished product 8a previously formed and processed by another injection molding apparatus is inserted into the female mold 20a and set (FIG. 8).
(D)), and thereafter, the second mold matching and the second injection molding are performed to form the hollow product 9a (FIG. 8E).
(F)). In such a case, a procedure of setting by an insert is required, but when the preformed product half 8a is viewed, the second and third molds 1
A hollow product 9 having a more complicated shape can be incorporated as a half of the product, instead of a simple shape in which the molds 9 and 20 are molded together.
a can be manufactured. In this embodiment, the number of the inserted product halves may be two instead of one. Furthermore, in the case where the half of the product molded separately is marked in this way, it is only necessary to insert the half of the product when performing secondary injection molding, so it is sufficient if there is a mold corresponding to that,
Therefore, for example, in the above embodiment, the second mold 1
9 can be carried out even without the male mold 19c, but when the male mold 19c is used, there is an advantage that it can be used also as the mold of the above-described fourth embodiment.

FIG. 9 shows a sixth embodiment. The sixth embodiment is of a center slide type, in which the primary injection and the secondary injection are performed simultaneously to form two hollows in a series of molding steps. The product 9 can be formed continuously. In other words, in this case, a pair of upper and lower female dies 22a, 22b, 24a, 24
b and male dies 22c and 24c are formed between the female dies. On the other hand, the second mold 23 has the female molds 22a, 22a.
b, 24a, male type 2 that can be selectively fitted to the top and bottom of 24b
3a, 23b, 23c, and 23d are formed, and a pair of female dies 23e and 23f are formed between the upper and lower male dies (FIG. 9A). And, for example, the male and female molds 22 on the lower half side
a and 23a, 24a and 23b, 22c and 23e and 24c
The mold is moved right and left so as to match each other (FIG. 9B). In this state, a first injection is performed with respect to the matched product to form first product halves 25, 26, and 27 (FIGS. 9B and 9C). Next, after the mold is moved left and right to release the mold, the second mold 23 is moved down (or may be rotated) so that the first product halves 25, 26, and 27 are positioned and opposed. The upper and lower male and female comrades 22b and 23c, 24b and 23d, 22c and 23e and 22c face each other (FIG. 9D). In this state, the molds are moved left and right to perform mold matching, and the second half is injected and bonded to the butting surfaces of the first product halves 25, 26, and 27 that abut each other in the lower half, while the second half is bonded in the upper half. One injection is performed to form the second product halves 28, 29, 30 (FIG. 9).
(E)). Thereafter, the first hollow article 9 formed by releasing the mold is released (FIG. 9 (F)). Second mold 2
3, the second product halves 28, 29, and 30 are aligned, and then the mold is moved left and right to form a mold. The lower halves of the male and female dies 22a and 23a, 24a and 23b, 22c
, 23e and 24c are matched (FIG. 9)
(G)), while secondary injection is performed for the secondary product, primary injection is performed for the primary product (FIG. 9 (H)). After that, the secondary product 9 is released from the mold.
This returns to the state of (C) or (D), and thereafter, this step is repeated. By doing so, the primary and secondary injection molding can be performed alternately and simultaneously, and the efficiency of hollow article injection processing can be increased. In this case, in order to perform the primary and secondary simultaneous molding described above, the injection molding machine is provided with respective corresponding injection nozzles so as to alternate primary and secondary simultaneous injection molding, respectively. Needless to say, it is necessary to perform the corresponding injection control.

Further, the present invention can be carried out by employing a mold shown as a seventh embodiment as shown in FIGS. In other words, in this case, when performing the secondary injection to bond at least three product halves 31, 32, 33 arranged side by side on the left and right, the injection material 34 for secondary injection can be combined into one. That is, this is configured to include first, second, and third molds 35, 36, and 37. The first mold 35 has a sprue for forming the product half 31 in the primary injection step. A sprue 35b different from 35a is formed, and the gate pin 38 of the secondary injection nozzle 37 penetrates through the sprue 35b, penetrates the product half 31, and forms the filling chamber S in the secondary mold 36. A male mold 36a. The second and third molds 3
6, 37 are sprues 36a, 3 for primary injection.
7a is formed. Further, the first and third molds 35, 37 are formed with rod-shaped male molds 35d, 37c which come into contact with each other when they are matched for primary injection.
0). When the primary injection is performed in this state, the product halves 31, 32 formed in the first and second molds 35, 36 have:
Communication holes 31a and 32a communicating with each filling chamber S are formed. The product halves 31, 32, 3 thus formed
When the dies 35, 36, and 37 are moved so that the three members abut each other, as shown in FIG. 11, the sprue 35b communicates with the pair of filling chambers S through the communication holes 31a and 32a.
In this state, the gate pin 38 is pulled to pull out the second injection nozzle 3.
When the second injection material 39 is injected from 7, the injection material 34 becomes
The hollow holes 40 to which the product halves 31, 32, 33 are bonded are formed by filling the communication holes 31a, 32a and the two filling chambers S. In this case, the gate pin 38 provided on the secondary injection nozzle 37 can be effectively used as a mold.
By protruding the nozzle gate pin 38 to the tip of the sprue 35b (FIG. 12), it is possible to eliminate the sprue runner and improve the yield. By doing so, the sprue of the primary injection and the sprue of the secondary injection are different. As a result, even in the case of the primary injection, the corresponding nozzle gate pins 40, 41, and 42 are connected to the sprue 35a after the primary injection. , 36a and 37a, there is an advantage that the sprue runner can be eliminated even in the primary injection. Incidentally, in this case, the male die 36a can be lengthened so that the abutting position with the valve gate pin 38 can be located on the left side of FIG. 10, and the abutting position is determined by the communication holes 31a and 32a.
It is needless to say that the size, length, and properties of the injection material can be arbitrarily set according to conditions.

Further, the mold may be of the eighth embodiment shown in FIG. This is basically the same as that of the seventh embodiment, in which a pair of filling chambers S are filled with a secondary injection material from one sprue runner. Are also given the same reference numerals. In this case, at the time of the primary injection, the valve gate pin 44 provided on the injection nozzle 43 for the secondary injection is fitted to the second mold 36, whereby the valve gate is provided in the primary injection step. This is to prevent the pin 44 from tilting or falling down due to the injection pressure at the time of the primary injection. Therefore, in this embodiment, the portion corresponding to the valve gate pin 44 of the second mold 36 is provided. The configuration is such that the male mold 36a is missing and a concave hole 36b into which the valve gate pin 44 is fitted is formed. In this embodiment, an injection nozzle for primary injection, which is different from that of the seventh embodiment, is of a type in which it is inserted into a mold.

FIGS. 14 and 15 show a mold according to a ninth embodiment. In this embodiment, as in the seventh and eighth embodiments, the secondary injection is performed from one injection nozzle.
Are formed only on the product half 49 formed in the second mold 46, and the secondary injection material 52 serving as an adhesive is to be secondarily injected from the secondary injection nozzle 51 here. . In order to implement this, it is necessary to form a communication hole in the product half 48 or 50 formed by the first mold 45 or the third mold 47 as in the above embodiment at the time of primary injection. Absent. Therefore, consideration for forming a communication hole in the product half portion 48 or 50 with a valve gate pin or a mold is unnecessary. In the seventh, eighth, and ninth embodiments, the communication holes formed in the center half of the product are separated from each other, for example, on the opposite side without being coincident with the injection position for secondary injection. Of course, it is good.

In each of the above embodiments, the hollow portion of the hollow product is formed on both sides of the second product half. However, the present invention is not limited to this. It becomes hollow like the form, but the other is a plate,
Alternatively, a bar-shaped product half may be bonded by secondary injection. An example of such a case is a side turn signal 52 as shown in FIG. In other words, the first half of the product becomes the lens portion 53, the second half of the product has the center of the body 54 in which the light bulb 56 is incorporated, and the side blinker 52 is connected to the vehicle outer panel 5
A third product half portion (FIG. 16) serving as an elastic movable piece 55 for detachably attaching to an attachment hole 57a formed in FIG.
(B)). In this case, the resin material 59 injected from the lens portion 53 for secondary injection is filled in a filling chamber S formed between the lens portion 53 and the body main body 54 for bonding the lens portion 53 and the body main body 54, and furthermore, The resin material 59 is filled in the filling chamber Sa formed between the concave groove 54a formed in the body main body 54 and the elastic movable piece 55, and the body main body 54 and the elastic movable piece 55 are bonded. (FIGS. 16A and 16C). Incidentally, in the present embodiment, the filling of the resin material 59 into the filling chambers S and Sa is performed by the provided injection nozzles. With this configuration, the body main body 59 and the elastic movable piece 59 are different from those of the related art shown in FIG.
There is the following advantage between the case where a is integrally formed by primary injection molding. That is, when such a product is mounted in the mounting hole 57a of the vehicle, the elastic movable piece 56 (58a) is pressed against one peripheral edge of the mounting hole 57 to be elastically deformed, and thereby the locking formed on the body main body. The groove 55d (59d) is inserted into the other peripheral edge of the mounting hole 57a and is forcibly fitted and locked. Thereafter, the elastic movable piece is resiliently repelled when the pressing force is released, so that it is prevented from coming off. It is designed to be attached
Therefore, the elastic movable piece 56 is attached to the body body 55 (59).
When the (59a) is elastically deformed, it is necessary to secure a space for the tip portion to be loosely fitted.
5b (59b) is formed. When the body groove 59 and the elastic movable piece 59a are integrally formed by primary injection molding as in the conventional case, the loose fit groove 59b and the elastic movable piece 59a overlap in the mold setting direction. Therefore, if the mold is used as it is, the mold cannot be removed. Conventionally, as shown in FIG. 17A, a mold for forming the overlapped portion 60 including the loose fitting groove 59b is set in a direction orthogonal to the mold setting direction (left-right direction) (front and back of the paper). Direction), and a body body 59 with an elastic movable piece 59a is integrally formed in combination with the movable mold. For this reason, in the body main body 59, a removal groove 59c for removing the movable die has to be formed in a state of continuing from the loose fitting groove 59b to the outer peripheral end (FIG. 17A).
(B)). However, the body body 55 and the elastic movable piece 56
Are separately molded in the primary injection step (FIG. 16 (B)),
By constructing this in a secondary injection step, the problem of the overlap as in the prior art described above is eliminated in the primary injection molding step, and the peripheral edge which does not require a cutout groove 58b is required. You can do flat products. As a result, conventionally, since it is not possible to remove the mold in this way, even a product that has to be molded using another movable mold can be easily molded, and further, there is no draft groove, and the design is improved. Thus, it is possible to manufacture an excellent product, and the effectiveness of the present invention is also confirmed here.

[Brief description of the drawings]

FIGS. 1A to 1F are schematic explanatory views showing states of an injection molding process according to a first embodiment.

FIG. 2 is an enlarged sectional view of a main part showing a mold state when primary injection is performed.

FIG. 3 is an enlarged cross-sectional view of a main part showing a state where molds are matched to perform secondary injection.

FIG. 4 is an enlarged sectional view of a main part showing a mold state when secondary injection is performed.

FIGS. 5A to 5F are schematic explanatory views showing states of an injection molding process according to a second embodiment.

FIGS. 6A to 6F are schematic explanatory views showing states of an injection molding process according to a third embodiment.

FIGS. 7A to 7F are schematic explanatory views showing states of an injection molding process according to a fourth embodiment.

FIGS. 8A to 8F are schematic explanatory views showing states of an injection molding process according to a fifth embodiment.

FIGS. 9A to 9I are schematic explanatory views showing states of an injection molding process according to a sixth embodiment.

FIG. 10 is a main part enlarged sectional view showing a mold state when primary injection is performed in the seventh embodiment.

FIG. 11 is an enlarged sectional view of a main part showing a state in which the molds of FIG. 10 have been matched to perform secondary injection.

FIG. 12 is an enlarged sectional view of a main part showing a state of a mold when secondary injection is performed for the one shown in FIG. 11;

FIG. 13 is an enlarged sectional view of a main part showing a mold state when primary injection is performed in the eighth embodiment.

FIG. 14 is an enlarged sectional view of a main part showing a mold state when primary injection is performed in the ninth embodiment.

FIG. 15 is an enlarged sectional view of a main part showing a state of a mold when secondary injection is performed for the one shown in FIG. 14;

FIG. 16A is a cross-sectional view of a vehicle side turn signal.
(B) is a cross-sectional view showing a combination of half of a product formed by primary injection molding, and (C) is an enlarged cross-sectional view of a main part of a side turn signal.

FIG. 17 (A) is an enlarged sectional view of a main part of a conventional vehicle side turn signal, and FIG. 17 (B) is a rear view thereof.

[Explanation of symbols]

 1, 11, 18, 22, 35 First mold 2, 12, 19, 23, 36 Second mold 3, 13, 20, 24, 37 Third mold 6, 31 Product half 7, 32 Product half Part 8, 33 Product half 9, 40 Hollow product 10, 34 Secondary injection material S Filling chamber

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hitoshi Kurihara 135-10 Nishishinmachi, Ota City, Gunma Prefecture Inside Oshima Electric Works Co., Ltd. (72) Takashi Isagi 135-10 Nishishinmachi, Ota City, Gunma Prefecture Co., Ltd. F-term in Oshima Electric Works (reference) 4F202 AG07 AH17 CA11 CB01 CB12 CB21 CK52 CK90 4F206 AG07 AH17 JA07 JB12 JB21 JN12 JQ62 JQ81

Claims (15)

[Claims] 1. A primary injection step comprising at least three adjacent dies in a series and forming at least three product halves in each of the dies by matching the adjacent dies. A secondary injection step of bonding the adjacent product halves together in a state where the molds are relatively moved and the adjacent product halves formed in the primary injection process are matched so as to abut each other. A method for injection molding a hollow product, characterized by comprising: 2. The method according to claim 1, wherein when three molds are used, one of them is a fixed mold, and the other two are movable molds. A method for injection molding a hollow product, wherein a half of a product formed in a mold is moved so as to abut a half of a product formed in a fixed mold. 3. The fixed mold according to claim 1, wherein when three molds are used, two of them are set so that a product half is molded at the same position in a primary injection step. One of the movable molds, and moving the one movable mold so that a product half formed in the movable mold abuts against a product half formed by the fixed molds. Characteristic injection molding method for hollow products. 4. The hollow product according to claim 2, wherein each mold is formed with a mold for simultaneously and alternately performing a primary injection step and a secondary injection step. Injection molding method. 5. The method of injection molding a hollow product according to claim 4, further comprising an injection nozzle for alternately and simultaneously executing a primary injection step and a secondary injection step. 6. The product half portion according to claim 1, 2, 3, 4, 5 or 5, wherein the product half portion sandwiched between adjacent product half portions on both sides includes:
Injection molding of a hollow product, wherein a flow path for flowing a resin material injected in a secondary injection step from a butt portion of one product half to a butt portion of the other product half is formed. Method. 7. A primary mold-matching means comprising at least three molds adjacent in a series, and molds each of the adjacent molds so as to form a product half. Primary injection means for injecting a resin material into each product to mold each product half, mold moving means for relatively moving a mold so that the molded product half is abutted, and the butted product An injection molding apparatus for a hollow product, comprising: a secondary injection means for injecting a resin material to bond the halves. 8. The method according to claim 7, wherein when three dies are provided, one of the dies is a fixed die, and the other two are movable dies. An injection molding apparatus for a hollow product, wherein a half of a product to be molded is set so as to move so as to abut a half of a product to be molded into a fixed mold. 9. The fixed mold according to claim 8, wherein when three molds are used, two of the molds are set so that a product half is molded at the same position in the primary injection step. One of the movable molds, and the mold moving means pushes the one movable mold to a product half formed by the fixed molds. An injection molding apparatus for hollow products, wherein the apparatus is set so as to be moved to fit. 10. The hollow product according to claim 7, wherein a mold for performing a primary injection step and a secondary injection step alternately and simultaneously is formed in each mold. Injection molding equipment. 11. The injection molding apparatus for hollow products according to claim 10, further comprising an injection nozzle for alternately and simultaneously executing a primary injection step and a secondary injection step. 12. The product half according to claim 7, 8, 9, 10, or 11, wherein a resin material injected in a secondary injection step is placed on one side of the product half between two adjacent product halves. Characterized in that a flow path forming means for forming a flow path for flowing from the butting portion to the butting portion of the other half of the product is provided. 13. The at least one mold according to claim 7, 8, 9, 10, 11, or 12, wherein at least one mold has an insert mold for incorporating a preformed product half to perform a secondary injection step. An injection molding apparatus for a hollow product, wherein the injection molding apparatus is formed. 14. A primary injection step in which three dies adjacent to each other in a series are provided on the left and right sides, and a half part of a product is injection-molded in a state where the adjacent dies are matched with each other. ,
A mold moving step of moving the center mold away from the mold matching area of the left and right molds while leaving the product halves in the left and right molds, and then performing mold matching so that the product halves remaining in the left and right molds abut each other. A method of injection molding a hollow product, comprising a secondary injection step of performing injection molding in order to abut and bond half of a product together. 15. A primary molding means comprising three adjacent dies in a series on the left and right sides, and a pair of adjacent dies, and a resin material is injected into the combined ones. Primary injection means for molding the product half by moving the center mold away from the mold matching area of the left and right molds while leaving the molded product half in the left and right molds, and the product remaining in the left and right molds Secondary mold matching means for performing mold matching so that the half halves abut each other, and secondary injection means for injecting a resin material so as to bond the butted product halves together. Injection molding equipment for hollow products.