JP3375918B2 - Injection molding equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention relates to injection molding KatachiSo location of the cross-sectional area toward the bottom portion from the opening for forming the container to expand.

[0002]

2. Description of the Related Art Conventionally, polyvinyl chloride (PVC), polyethylene terephthalate (PET), polypropylene (PP) and the like have been known as materials for resin containers. Among these materials, PVC generates chlorine gas at the time of combustion and thus has poor recyclability, and has a problem of destroying the environment by discarding it. Further, there is a strong demand for the manufacturer to carry out a recycling process, and PET produces a high temperature during combustion, which poses a problem of imposing an excessive burden on the manufacturer. For this reason, PP tends to be used as a material for resin containers.

On the other hand, in manufacturing a resin container, blow molding or injection molding is used depending on the shape, function and material of the container. In blow molding, a material is expanded in a cavity, and a container having a predetermined shape is formed only by contact with the inner surface of a cavitity without using a core forming the inner surface of a product. Therefore, blow molding
It is possible to manufacture a container having a high degree of freedom in the shape of the container and having an inner diameter that increases from the opening to the bottom. However, in blow molding, since the material is expanded in the cavity, it is difficult to increase the thickness of the container to such an extent that sufficient strength can be secured. In blow molding, since the core does not contact the inner surface of the container, the inner surface of the container cannot be formed smoothly.
When PP is used as a material having a low transparency as compared with the above, there is a problem that it is not possible to give sufficient transparency to the container, making it difficult to visually visually recognize the type and amount of stored items in the container from the outside. Become.

At this point, in injection molding, resin is injected between the cavity that comes into contact with the outer surface of the container, which is a product, and the core that comes into contact with the inner surface of the container. The core and cavity contact the outer surface,
The thickness of the container can be made thick enough to ensure sufficient strength, and the inner surface of the product can be made smooth, so the transparency of the product can be sufficiently high and the type of items to be stored. It is possible to form a container whose storage amount can be easily visually recognized from the outside.

[0005]

However, in the conventional injection molding method used for manufacturing a resin container, the resin which is the material between the cavity and the core is positioned with the core positioned in the cavity (mold clamping). After injecting, the core was pulled out from the cavity (mold opening), and the volume of the core was changed until the product was removed from the outer peripheral portion of the core. Therefore, in the conventional injection molding method, it is not possible to manufacture a container having a shape in which the inner cross-sectional area expands from the opening to the bottom, and at the same time, it is possible to easily remove the product container from the core. In order to do so, it is necessary to provide a so-called draft in the shape of the inside of the container, which reduces the cross-sectional area from the opening toward the bottom.

From these facts, in a container having a neck portion to which a lid is mounted in the opening, the inner diameter of the portion other than the neck must be smaller than the inner diameter of the neck portion, and the wall thickness of the portion other than the neck portion is small. When PP is used as a material, which is extremely thick and has a lower transparency than PET, there is a problem that the transparency cannot be maintained to the extent that the contents can be visually recognized from the outside. Therefore, with the conventional resin molding method, it was not possible to manufacture a container having a high transparency and a neck portion using PP as a raw material.

The object of the present invention is to reduce the volume of the core when the mold is opened to separate the cavity from the core,
The container shape to expand the cross-sectional area of the inside toward the bottom portion from the opening and having a transparency enough to visually recognize the received material from the outside, to provide injection molding KatachiSo location capable of producing PP as a material Especially.

[0008]

The present invention has the following structure as means for solving the above problems.

(1) A cylindrical shape having an opening and a bottom
A key used for injection molding of containers that comes into contact with the outer peripheral surface of the container.
In an injection molding device having a cavity and a core that comes into contact with the inner peripheral surface of the container, the cylindrical shape of the inner peripheral surface of the container
Partial circle with one length out of four divided into two lengths
The outer peripheral surfaces 11a and 12a constituted by the peripheral surface of the container
Two that gradually reduce the distance from the opening to the bottom
Slope 11b and slope 11c and slope 12b and slope
Surface 12c, the spacing gradually decreases from the opening of the container to the bottom.
Increasingly shortened inclined surfaces 11d and 12d and the container
A pair having vertical surfaces 11e and 12e orthogonal to the axial direction
Drive side partial cores 11 and 12 and a cylinder of the inner peripheral surface of the container
The other of the four divided shapes in the circumferential direction with two different lengths
An outer peripheral surface 13a constituted by a partial circumferential surface having a length of
14a, the spacing gradually increases from the opening of the container to the bottom
And the inclination of the driving side partial cores 11 and 12
Contact the surfaces 11b, 12b and the inclined surfaces 11c, 12c
Slopes 13b and 14b, and orthogonal to the axial direction of the container
Pair of driven parts having vertical surfaces 13c and 14c
Inclination of the cores 13 and 14 and the drive side partial cores 11 and 12
Inclined surfaces 15a and 15 contacting the inclined surfaces 11d and 12d
b, inclined surfaces 13b and 1 of the driven side partial cores 13 and 14
4b and the inclined surfaces of the partial cores 11 and 12
11b, 12b and inclined surfaces 11c and 12c are flush with each other
The slopes 15c and 15d and the axial direction of the container are orthogonal to each other.
The partial core 15 including the vertical surface 15e
When the mold is opened to separate the cavity and the core,
Drive along with the movement of the partial core 15 in the axial direction of the container.
The direction in which the side partial cores 11 and 12 are orthogonal to the axial direction of the container
And the driven side partial core 13 and
It is characterized in that 14 are brought close to each other in a direction orthogonal to the axial direction of the container . (2) The inclined surfaces 11d, 1 of the drive side partial cores 11, 12
2d and slopes 15a, 15b of the partial core 15
Arrangement G is the drive side of the partial core 15 in the axial direction of the container.
The maximum movement value relative partial cores 11, 12 as L _1, volume
From the inner diameter D1 of the neck portion and the inner diameter D3 of the body portion of the container, G> (D3-D1) / 2L _{1 is} determined .

(3) One end has the driven side partial cores 13 and 14
And the other end is fixed to the drive side partial core 11,
12 is inserted into the through hole of the plate supporting 12 incliningly.
Including an angular pin, angular contact from the axial direction of the container
Support the driven side partial cores 13 and 14 at each angle θ
Supports the drive side partial cores 11 and 12 with respect to the plate
Let L _{4 be} the maximum movement of the plate container in the axial direction.
From the inner diameter D1 of the neck and the inner diameter D3 of the body of the container, tan θ> (D3-D1) / 2L _{4 is} determined .

[0011]

1 is a sectional view showing the shape of a container molded by an injection molding method and an injection molding apparatus according to an embodiment of the present invention. The container 100 is a cylindrical bottomed container having an opening 110, a neck 120, a body 130, and a bottom 140. An unillustrated male screw portion is formed on the outer peripheral surface of the neck portion 120, and the lid body 200 is attached to the male screw portion.
The female threaded portion formed on is threadedly engaged. With the female thread portion of the lid body 200 screwed onto the male thread portion of the neck portion 120, the lid body 20
The outer diameter of the neck portion 120 is made smaller than the outer diameter of the body portion 130 by the thickness of the lid body 200 so that the outer peripheral surface of 0 and the outer peripheral surface of the body portion 130 are substantially flush with each other. Also,
The container 100 includes a neck portion 120, a body portion 130, and a bottom portion 14.
It has a uniform thickness over the entire 0. Therefore, the inner diameter of the neck portion 120 is smaller than the inner diameter of the body portion 130,
The inner diameter of the container 100 increases from the opening 110 toward the bottom surface 140 in three stages D1 to D3. That is, the neck portion 120 has an axially uniform inner diameter D1 and the body portion 130.
A uniform inner diameter D3 in the axial direction and a value D between the inner diameter D2 at the joint between the neck 120 and the body 130 are
There is a relationship of 1 <D2 <D3.

[0012] The material of the container 100 is selected mainly in consideration of the burden on the manufacturer regarding the disposal process and the reduction of the influence on the environment at the time of combustion, and PP is used as an example. In addition, the thickness t of the container 100 is set so as to obtain a strength commensurate with the weight of the object to be stored under the condition that transparency is ensured so that the object can be visually recognized from the outside of the container 100 based on the characteristics of the material. Should be as thick as possible,
As an example, it is set to 1 mm. Incidentally, in the blow molding method, it is difficult to mold a container having a sufficient thickness to obtain a strength commensurate with the weight of the object to be stored, and a mold contacting the inner peripheral surface of the container is not used. Therefore, the inner peripheral surface of the container cannot be formed smoothly, and the transparency of the container 100 is significantly reduced. Therefore, the container 100 having sufficient transparency and strength uses a cavity that is a mold that abuts the outer peripheral surface of the container 100 that is a molded product, and a core that is a mold that abuts the inner peripheral surface of the container 100. It must be molded using an injection molding method.

FIG. 2 is a perspective view showing an example of the structure of the core used in the injection molding apparatus according to the embodiment of the present invention. FIG. 2 (A) is an external view of the integrated core, and FIG. 2 (B) is an assembly drawing of the core. The core 10 is composed of a total of five partial cores 11 to 15. The partial cores 11 to 14 are the neck portion 120 and the body portion 130 of the container 100.
The inner surface of is molded into two pairs in the inner peripheral direction. That is,
The partial core 11 and the partial core 12 form a pair of driving side partial cores, and the partial core 13 and the partial core 14 form another pair of driven side partial cores. Partial core 11-
14 molds the inner surfaces of the neck portion 120 and the body portion 130 of the container 100, and also molds a part of the inner surface of the bottom surface portion 140. The partial core 15 is located in the space surrounded by the partial cores 11 to 14 in the plane orthogonal to the axial direction of the container 100, and forms the remaining part of the inner surface of the bottom surface portion 140.

The shape of the partial cores 11 to 15 will be described in more detail below.
Outer peripheral surfaces 11a and 12a constituted by partial circumferential surfaces of one length of the inner circumferential surfaces of the neck portion 120 and the body portion 0 of 0 divided into four in the circumferential direction by two types of lengths,
Two inclined surfaces 11b and 11 having a distance gradually decreasing from the opening 110 of the container 100 toward the bottom surface 140.
c and the inclined surface 12b and the inclined surface 12c, the partial core 11 and the partial core 12, the inclined surface 11 whose distance gradually decreases from the opening 110 of the container 100 toward the bottom surface 140.
d and 12d, and vertical surfaces 11e and 12e orthogonal to the axial direction of the container 100.

The partial cores 13 and 14 are provided in the container 10
Outer circumferential surfaces 13a and 14a constituted by partial circumferential surfaces of the other length of the inner circumferential surfaces of the neck portion 120 and the body portion 0 of 0 divided into four in the circumferential direction by two types of lengths,
The distance between the partial core 13 and the partial core 14 gradually decreases from the opening 110 of the container 100 toward the bottom surface 140, and the inclined surfaces 11b of the partial cores 11 and 12,
12b and inclined surface 13 contacting inclined surfaces 11c and 12c
b and 14b, and vertical surfaces 13c and 14c orthogonal to the axial direction of the container 100.

Further, the partial core 15 has an inclined surface 15 which contacts the inclined surfaces 11d and 12d of the partial cores 11 and 12, respectively.
a and 15b, the inclined surfaces 13b and 14b of the partial cores 13 and 14, and the inclined surfaces 11b and 12b of the partial cores 11 and 12 and the inclined surfaces 15c and 15d which are flush with the inclined surfaces 11c and 12c, and the container 100. It includes a vertical surface 15e orthogonal to the axial direction of. The inclined surfaces 15a and 15b of the partial core 15, the longitudinal direction of the slider is formed to protrude. On the other hand, the inclined surfaces 11a and 12a of the partial core 11 and 12, groove portions in the longitudinal direction is formed. Slider is fitted from the opening 110 of the container 100 in the groove. The inclined surfaces 11d and 12d of the drive-side partial cores 11 and 12 and the inclined surfaces 15a and 15 of the partial core 15
The gradient G of b corresponds to the partial core 1 with respect to the partial cores 11 and 12.
5, the maximum movement amount of the container 100 in the axial direction is L ₁ , the inner diameter D1 of the neck portion 120 and the body portion 130 of the container 100.
From the inner diameter D3 of G> (D3-D1) / 2L ₁ ...

Further, the inclined surfaces 11b and 12b and the inclined surfaces 11c and 12c of the driving side partial cores 11 and 12, the inclined surfaces 13b and 14b of the driven side partial cores 13 and 14, and the inclined surfaces 15c and 15d of the partial core 15. The gradient (inclination angle) will be described later.

FIG. 3 is a perspective view showing an example of the structure of a cavity used in the injection molding apparatus according to the embodiment of the present invention. The cavity 20 is the body 130 of the container 100.
And a body cavity 21 having a hollow cylindrical shape that matches the shape of the outer surface of the bottom surface 140, and a neck cavity 22 having an annular shape that matches the shape of the outer surface of the neck 120.
And consists of. The neck cavity 22 is a partial cavity 22a divided in a direction orthogonal to the axial direction of the container 100.
And 22b. This cavity 2
Container 10 melted between the cavity 20 and the core 10 from a nozzle described later with the core 10 inserted in
0 material is injected. A through hole 21 a is formed in the center of the surface of the body cavity 21 that faces the bottom surface 140 of the container 100. The material ejected from the nozzle is filled between the cavity 20 and the core 10 via the through hole 21a.

Further, as shown in FIG. 2 (A), the partial core 1
In the core 10 in which 1 to 15 are integrated, the partial cores 11 to 11
The outer diameter of 14 is approximately equal to the inner diameter D3 of the body 130 of the container 100, and the inner diameter of the neck cavity 22 is
The outer diameter of the neck portion 120 of the container 100 is smaller than the inner diameter of the body portion 130, as is apparent from FIG. 1. Therefore, the outer diameter of the integrated core 10 is larger than the inner diameter of the neck cavity 22, and the core 10 inserted into the cavity 20 cannot be pulled out to the outside of the cavity 20 in an integrated state.

FIG. 4 is a diagram showing the structure of the plate in the injection molding apparatus. The injection molding apparatus according to this embodiment includes five plates 31 to 35 that are movable in the axial direction of the container 100. The plate 31 has
The nozzle 1 of the injection molding device penetrates. The body cavity 21 is fixed to the plate 32. The plate 33 includes a neck cavity 22 and driven side partial cores 13 and 14
Is movably held in a direction orthogonal to the axial direction.
The drive side partial cores 11 and 12 are movably held by the plate 34 in a direction orthogonal to the axial direction. The partial core 15 is fixed to the plate 35.

Guide members for defining the movement directions of the plates 31 to 35 are arranged at predetermined positions, and the plates 31 to 35 are adjacent to each other as shown in FIG. 4 (A). The container 100 is moved in the axial direction between the mold clamping state in which the container 100 contacts with the mold and the mold opening state in which the molds are separated from each other as shown in FIG. An angular pin for moving the neck cavity 22 in a direction orthogonal to the axial direction by fixing the plate 33 to the plate 32 in the direction of separation is fixed to the plate 32, and the driven side partial core 13 held by the plate 33. , 1
An angular pin for fixing the driven side partial cores 13 and 14 in the direction orthogonal to the axial direction by fixing the plate 34 to the plate 33 in the direction of separation from the plate 33 is fixed. These angular contact pins will be described later.

5 and 6 are a side view and a plan view for explaining the operation at the time of mold opening in the above injection molding apparatus.
As shown in FIGS. 5 (A) and 6 (A), the plate 31
~ 35 are in the mold clamping state where they are in contact with each other, the partial core 11 ~
The core 10 in which 15 is integrated is inserted into the cavity 20 in which the body cavity 21 and the neck cavity 22 are integrated. In this state, the molten material is injected between the outer side surface of the core 10 and the inner side surface of the cavity 20 and is cured by cooling to form the container 100.

When the container 100 is sufficiently cooled, FIG.
As shown in (B) and FIG. 6 (B), the plate 35 moves in the arrow X direction, and the mold opening operation is started. A spring (not shown) is arranged as a guide member between the plate 34 and the plate 35, and the plates 31 to 31 are provided until the movement amount of the plate 35 exceeds the maximum movement amount L ₁ of the plate 35 with respect to the plate 34. The plate 35 remains in contact with the plate 3 while the 34 remains in contact with each other.
Away from 4. At this time, the slide groove portion of the drive-side partial cores 11, 12 slider partial cores 15 fixed to the plate 35 is supported on the plate 34 in the axial direction of the container 100, the drive-side partial core in the plate 34 11,
12 move toward each other. Here, since the slopes G of the inclined surfaces 11d and 12d of the drive side partial cores 11 and 12 and the inclined surfaces 15a and 15b of the partial core 15 are determined by the above formula 1, the partial core 15 is indicated by the arrow X direction. Direction (axial direction of the container 100) , the outer diameters of the outer peripheral surfaces of the drive side partial cores 11 and 12 become smaller than the neck portion 120 of the container 100.
Is smaller than the inner diameter D1.

When the plate 35 continues to move in the arrow X direction beyond the maximum movement amount L ₁ from the state shown in FIGS. 5B and 6B, the guide member (not shown) moves the plate 35 in the X direction. The movement is transmitted to the plate 34.
At least one pair of magnets that attract with a predetermined magnetic force are attached to the plates 34 and 33 as guide members. Therefore, the plate 34 to which the movement of the plate 35 in the arrow X direction is transmitted is separated from the plate 32 together with the plate 33. When the movement amount of the plate 34 and the plate 33 in the arrow X direction exceeds the maximum movement amount L ₂ with respect to the plate 34, the movement of the plate 35 in the arrow X direction is performed via the guide member (not shown).
Be transmitted to. This causes the plate 32 to move in the direction of the arrow X until the distance between the plate 32 and the plate 31 reaches the maximum movement amount L _3.
Moving in the direction, the plates 31 to 35 are brought into the state shown in FIGS. 5 (C) and 6 (C).

Here, one end of two angular pins 41 and 42 is fixed to the plate 32. As shown in FIG. 6, the angular pins 41 and 42 are arranged such that their open end sides are inclined in a direction in which they are separated from each other in a plane. The open ends of the angular pins 41 and 42 are fitted into the through holes 51a and 51b of the partial cavities 22a and 22b, which form the neck cavity 22 supported by the plate 33 during mold clamping. Therefore, when the plates 33 and 34 move in the arrow X direction with respect to the plate 32 from the state shown in FIG. 6B, the through holes 51a and 51b move the shaft portions of the angular pins 41 and 42 toward the open end side. The sliding causes the partial cavities 22a and 22b of the plate 33 to move in a direction away from each other in a plane. As a result, the partial cavity 2
The inner peripheral surfaces of 2a and 22b do not contact the outer peripheral surface of the neck portion 120 of the container 100.

When the plate 35 continues to move in the arrow X direction from the state shown in FIGS. 5 (C) and 6 (C) and the amount of movement of the plate 32 reaches the maximum amount of movement L ₃ , the plate 3
2 and the plate 33 do not move in the arrow X direction.
Accordingly, the movement of the plate 35 causes the plate 34 to move to the plate 33 against the magnetic attraction force of the magnet.
5D and FIG.
As shown in (D), the plate 34 moves in the arrow X direction until the distance between the plate 34 and the plate 33 reaches the maximum movement amount L ₄ .

Here, one ends of the two angular pins 43 and 44 are fixed to the driven side partial cores 13 and 14 supported by the plate 33. As shown in FIG. 6, the angular pins 43 and 44 are arranged so that their open end sides are inclined in a direction in which they are separated from each other in a plane. The open ends of the angular pins 43 and 44 have through holes 52a, 5a formed in the plate 34 during mold clamping.
It is fitted in 2b. Therefore, when the plate 34 moves in the arrow X direction with respect to the plate 33 from the state shown in FIG. 6C, the through holes 52a and 52b move to the angular pin 4
The shaft portions of 3, 44 slide toward the open end side, and the driven side partial cores 13 and 14 of the plate 33 move in a direction in which they approach each other in the plane. The angular pins 43, 44 and the through holes 52a, 52b correspond to the second moving mechanism of the present invention.

At this time, the inclination angle θ of the agula pins 43 and 44 from the arrow X direction is set to L ₄ as the maximum movement amount of the plate 34 with respect to the plate 33 in the arrow X direction, and the container 1
From the inner diameter D1 of the neck portion 120 and the inner diameter D3 of the body portion 130 at 00, tan θ> (D3−D1) / 2L ₄ ... Therefore, the movement amount of the plate 34 with respect to the plate 33 in the arrow X direction is the maximum movement amount L.
_When reaching ₄ , the outer diameter of the driven side partial cores 13 and 14 becomes
It is smaller than the inner diameter D1 of the neck portion 120 of the container 100.

The driven side partial cores 13 and 14 move toward each other as the plate 34 moves in the direction of the arrow X, but are supported by the plate 34 between the driven side partial cores 13 and 14. The drive side partial cores 11 and 12 are located. Therefore, in order to prevent the driven side partial cores 13 and 14 approaching each other from interfering with the drive side partial cores 11 and 12, the inclined surfaces 11b and 11c of the drive side partial core 11 and the inclined surface 12 of the drive side partial core 12 are prevented.
The angles of inclination of b, 12c and the inclined surfaces 13b and 14b of the driven side partial cores 13 and 14 from the direction of arrow X must be equal to or greater than the inclination angle θ of the angular pins 43 and 44.

As described above, FIG. 5D and FIG.
As shown in (D), when the moving amount L of the plate 35 reaches L = L ₁ + L ₂ + L ₃ + L ₄ , the core 1 is pulled out from the inside of the body cavity 21, and the partial cores 11 to 14 are The outer diameter is smaller than the inner diameter D1 of the neck portion 120 of the container 100, and the inner diameter of the neck cavity 22 is larger than the outer diameter of the neck portion 120 of the container 100. As a result, the container 100 injection-molded in a shape in which the inner diameter is reduced from the opening 110 toward the bottom surface 140 can be easily taken out from between the core 1 and the cavity 2.

As is apparent from FIG. 6D, in order to facilitate the work of taking out the injection-molded container 100 between the plate 32 and the plate 33, the arrow X of the plate 34 with respect to the plate 32 is used. The maximum amount of movement L ₂ in the direction should be equal to or greater than twice the axial length of the container 100 plus the amount of protrusion of the angular pins 41, 42 in the plate 32.

As shown in FIGS. 5 (C) and 6 (C), after the amount of movement of the plate 32 in the direction of arrow X reaches the maximum amount of movement L ₃ , the plate 31 is also slightly moved by the amount of arrow X. Although it moves in the direction, it does not affect the operation of the partial cores 11 to 15. Therefore, the movement of the plate 31 is not considered here.

[0033]

According to the present invention, the following effects can be obtained.

[0034] When separating the key Yabiti a core, a plurality of pairs of partial cores divided along the inner circumferential direction of the container, by moving in a direction coming close sequentially to each other, opening direction mold volume of the core The cavity and the core are separated in a state of being contracted in a direction orthogonal to, and a gap is formed between the inner surface of the formed container and the outer surface of the core. Accordingly, even when a container having a shape in which the inner cross-sectional area expands from the opening to the bottom is formed, the formed container can be easily removed from the core .

[Brief description of drawings]

FIG. 1 is a sectional view showing a shape of a container molded by an injection molding method and an injection molding apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an example of the configuration of a core used in the injection molding apparatus according to the embodiment of the present invention.

FIG. 3 is a perspective view showing an example of the configuration of a cavity used in the injection molding apparatus according to the embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a plate in the injection molding apparatus.

FIG. 5 is a side view for explaining the operation of the injection molding device when the mold is opened.

FIG. 6 is a plan view illustrating an operation of the injection molding apparatus when the mold is opened.

[Explanation of symbols]

10-core 11,12-Partial core on drive side 13, 14-Partial core on driven side 15-partial core 16-slider 17-groove 20-cavity 21-Body cavity 22-neck cavity 31-35 plate 41-44-angular pin 51a, 51b, 52a, 52b-through hole 100-container 110-opening 120-neck 130-Body 140-bottom part

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-8-118374 (JP, A) JP-A-59-133010 (JP, A) JP-A-5-57760 (JP, A) JP-A-63- 242617 (JP, A) JP-A-5-147082 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B29C 45/44

Claims (3)

(57) [Claims] 1. A cylindrical container having an opening and a bottom.
Used for injection molding of a container that contacts the outer peripheral surface of the container
Injection molding having a tee and a core that abuts the inner peripheral surface of the container
In the device , the cylindrical shape of the inner peripheral surface of the container is divided into 4 types with two lengths in the circumferential direction.
It consists of a partial circumferential surface of one of the divided lengths.
Outer peripheral surfaces 11a and 12a, from the opening of the container to the bottom
The two inclined surfaces 11b whose distance gradually decreases toward
Slope 11c and slope 12b and slope 12c, opening of container
Inclined surface where the distance gradually decreases from the mouth to the bottom
11d and 12d and hanging perpendicular to the axial direction of the container
A pair of drive side partial cores 1 having faces 11e and 12e
1 and 12 and the cylindrical shape of the inner peripheral surface of the container 4 in two kinds in the circumferential direction.
It consists of a partial circumferential surface of the other length
Outer peripheral surfaces 13a and 14a, from the opening of the container to the bottom
As the distance gradually decreases, the drive side partial core
11 and 12 inclined surfaces 11b and 12b and inclined surface 11
inclined surfaces 13b and 14b, which are in contact with c and 12c,
The vertical surfaces 13c and 14c perpendicular to the axial direction of the container
The pair of driven-side partial cores 13 and 14 and the inclined surfaces 11d and 12d of the driving-side partial cores 11 and 12
The inclined surfaces 15a and 15b that come into contact with the driven side partial core 1
When contacting the inclined surfaces 13b and 14b of 3 and 14,
The inclined surfaces 11b and 12b of the partial cores 11 and 12
Inclined surfaces 15c and 15 flush with the inclined surfaces 11c and 12c
d, and a vertical surface 15e orthogonal to the axial direction of the container.
The partial core 15 and the core are configured to separate the cavity from the core.
When the mold is opened, the partial core 15 can be moved in the axial direction of the container.
As a result, the drive side partial cores 11 and 12 are moved in the axial direction of the container.
And the driven side part
The distribution cores 13 and 14 are mutually connected in a direction orthogonal to the axial direction of the container.
An injection molding device characterized by bringing it closer to the body. 2. The inclined surface 1 of the drive side partial cores 11 and 12
1d, 12d and inclined surfaces 15a, 1 of the partial core 15
5b with a gradient G of the partial core 15 in the axial direction of the container
The maximum amount of movement relative to the driving-side partial cores 11, 12 and L ₁
The inner diameter D1 of the neck and the inner diameter D3 of the body of the container
From, G> (D3-D1) / 2L injection molding apparatus according to claim 1, characterized in that determined by _1. 3. One end is fixed to the driven side partial cores 13 and 14.
Is fixed and the other ends are the drive side partial cores 11 and 12.
Angi that slants into the through hole of the plate that supports the
Including the urapin, the angular pin from the axial direction of the container
Each of the tilts θ has a pre-support for supporting the driven side partial cores 13 and 14.
For supporting the drive side partial cores 11 and 12 with respect to
Set the maximum amount of axial movement of the container for the container to L ₄
The injection molding apparatus according to claim 1 or 2 , wherein tan θ> (D3-D1) / 2L _{4 is} determined from the inner diameter D1 of the neck portion and the inner diameter D3 of the body portion .