JPH0541860Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a rotary injection molding machine, which eliminates the need to adjust the height of the injection device when replacing molds with different mold thicknesses, and moreover, allows the nozzle of the injection device to be fixed to the nozzle touch. This invention relates to a rotary injection molding machine that is capable of continuous molding operation in a closed state.

(Background technology) A rotary injection molding machine used for multi-color molding or insert molding has a fixed plate and a rotary plate disposed on a movable plate located above the fixed plate. There is a type in which a plurality of sets of molds are arranged, and the plurality of sets of molds can be simultaneously clamped at a plurality of rotational positions of the rotary plate by lowering the movable platen.

Therefore, in conventional rotary injection molding machines of this type, there are those in which the rotating plate is placed on the fixed plate side, and those in which the movable plate is placed below the fixed plate. Similar to other types of vertical rotary injection molding machines, a resin passage for guiding the resin material into the cavity of the mold is formed on the parting surface of the mold, and the nozzle of the injection device touches the nozzle. The nozzle touch surface to be pressed was formed on the parting surface of the mold.

For this reason, in this type of conventional rotary injection molding machine, when replacing the mold, if the old and new molds have different mold thicknesses, the height of the injection device is adjusted to the height of the new mold (lower mold). ), the height adjustment operation is extremely troublesome, and since the injection device needs to have such a height adjustment function, the support mechanism of the injection device is extremely complicated. I was used to it. Furthermore, for the same reason, that is, the nozzle touch surface is formed on the parting surface of the mold, it is necessary to move the injection device forward and backward with the mold in the clamped state each time the mold is opened and closed. Therefore, there was a problem in that the molding cycle was lengthened by the time required for the forward and backward operations of the injection device.

(Problem to be solved) The present invention was developed against the background of the above, and its problem is to adjust the height of the injection device one by one when replacing molds with different mold thicknesses. To provide a rotary injection molding machine which can continuously perform opening and closing operations of a mold, and thus molding operations, without having to perform the above operations, and with an injection device held in a nozzle touch state.

(Solution Means) In order to solve this problem, the present invention provides a fixed plate and a rotary plate disposed on a movable plate located above the fixed plate so as to be opposite to each other. In a rotary injection molding machine, a plurality of sets of molds are arranged, and the plurality of sets of molds can be simultaneously clamped at a plurality of rotational positions of the rotary plate by lowering the movable platen. , a resin passage for guiding the resin material into the cavity of the mold is provided so as to pass through the lower mold attached to the fixed plate, and the inside of the lower mold mounting plate for attaching the lower mold to the fixed plate. is provided so as to extend in the horizontal direction, and is opened in the side surface of the lower die mounting plate, and by horizontal movement of a predetermined injection device, the nozzle of the injection device is caused to touch the nozzle at the opening of the resin passage. Therefore, the resin material is injected into the cavity of the mold through the resin passage.

(Function) In a rotary injection molding machine having such a configuration, a resin passage is provided to penetrate the lower mold and extend horizontally inside the lower mold mounting plate for attaching the lower mold to the fixed platen. Since the opening through which the nozzle of the injection device can touch the nozzle is provided on the side of the lower mold mounting plate, the opening of the resin passage can be placed at the same height regardless of the thickness of the mold (lower mold). Can be set to . Therefore, by providing the openings of the resin passages at the same height position, even when replacing molds with different mold thicknesses, it is possible to adjust the height position of the injection device one by one according to the mold thickness. You can make it unnecessary. Moreover, since the nozzle touch can be performed by moving the injection device in the horizontal direction, even if the mold (lower mold) is changed, the nozzle can be accurately brought into contact with the opening of the resin passage. This also makes adjusting the nozzle touch extremely easy.

Furthermore, even if the injection device is held in the nozzle touch state, there is no interference between the upper mold, which is a movable mold, and the injection device, so there is no need to retreat the injection device from the nozzle touch position when opening and closing the mold. Therefore, it is possible to perform the molding operation continuously while the injection device is held in the nozzle touch state.

(Example) Hereinafter, in order to clarify the present invention more specifically, one example thereof will be described in detail based on the drawings.

First, in FIGS. 1 and 2, 10 is
It is a lower surface plate as a fixed plate, and above it,
An upper surface plate (not shown) is connected and supported by tie rods (not shown). A movable platen 12 is provided between the upper surface plate and the lower surface plate 10, and a hydraulic cylinder 14 is provided between the upper surface plate and the upper surface plate.
The movable platen 12 is guided by tie rods to be raised and lowered.

A rotary plate 16 is disposed on the lower surface of the movable plate 12 so as to be rotatable around the center line while being held by a rotation holding means (not shown), and a rotary plate 16 is disposed on the upper surface of the movable plate 12 so as to be rotatable around the center line. Rotating shaft 18 provided at
An indexer 20 is provided for rotating the turntable 16 to a plurality of rotational positions. Then, the rotary disk 1 by the indexing machine 20
A plurality of upper molds 22 and a plurality of lower molds 24 are respectively attached to the lower surface of the rotary plate 16 and the upper surface of the lower surface plate 10 so as to face each other at the plurality of rotational positions of the rotary plate 16. By lowering the movable plate 12 while being rotated to the rotation position, the plurality of upper molds 2
2 and a plurality of lower molds 24 are pressed simultaneously.

In addition, here, the rotary plate 16 and the lower surface plate 10
Two upper molds 22, 22A, 22B and two lower molds 24, 24A, 24B are respectively attached to the rotary disk 16 by the indexing machine 20.
The two upper molds 22A, 22B are rotated to two rotational positions separated by 180°, and in the two rotational positions of the rotary plate 16, the two upper molds 22A, 22B are moved based on the downward movement of the movable platen 12. and the two lower molds 24A, 24B are pressed together at the same time. In other words, here, two sets of molds are pressed together at the same time.

Here, the two upper molds 22A and 22B attached to the rotary plate 16 have the same molding surface shape, but the lower mold 24A and 22B attached to the lower surface plate 10,
24B have different molding surface shapes, and as a result, as shown in FIGS. 3 and 5, the cavity 26 formed between the upper molds 22, 22A, 22B and the lower mold 24A. than upper mold 2
The cavity 28 formed between 2, 22A, 22B and the lower mold 24B has a larger cavity volume. That is, as shown in FIGS. 3 to 5, the protrusion 30 is formed on the lower mold 24A, but no such protrusion 30 is formed on the lower mold 24B. , a lower mold 24B that does not have such a protrusion 30
The lower die 24 having such a protrusion 30 is
A cavity with a larger volume is formed between the upper molds 22, 22A, and 22B than in A.

By the way, in order to mold a predetermined molded product, for example, a two-color molded product, using such a rotary injection molding machine, first, as shown in FIG. A first resin material 32 is placed in the cavity 26 formed between the upper mold 22 (for example, the upper mold 24A) which is mold-matched to the mold.
eject. After the first resin material 32 is cooled and solidified, as shown in FIG.
Raise the movable platen 12 and move the upper mold 22A to the lower mold 24A.
After opening the mold, the indexing machine 2
Rotate the rotary disk 16 by 180° at 0. Note that at this time, the cooled and solidified first resin material 32 is fixed to the upper mold 22A side, as shown in FIG. 4.

Once the rotation operation of the rotary disk 16 is completed,
The movable platen 12 is lowered again, and the upper mold 22A holding the first resin material 32 integrally is closed and pressed against the lower mold 24B, and the upper mold 22A and the lower mold 24 are
A cavity 28 is formed with B. As is clear from FIG. 5, a part of the volume of the cavity 28 formed between the upper mold 22A and the lower mold 24B is occupied by the first resin material 32.
A volume portion corresponding to the protrusion 30 of the lower mold 24A is left as a void, and after the upper mold 22A and the lower mold 24B are pressed together, a first A second resin material 34 of a different color from the resin material 32 is injected. As a result, the first resin material 32 and the second resin material 3
4 are integrally joined, and when the upper mold 22A is opened from the lower mold 24B by the next upward movement of the movable platen 12, the two-color molded product is molded. It is taken out from the mold 22A.

As is well known, when the upper mold 22A is pressed onto the lower mold 24A, the upper mold 22B is pressed against the lower mold 24B, and the upper mold 22A is pressed against the lower mold 24B. Sometimes, it will be clamped by the lower die 24A. Then, as in the case of the upper mold 22A, the cavity 2 formed between the lower mold 24A and the lower mold 24A is pressed.
In the state in which the first resin material 32 is injected into the lower mold 24B and the lower mold 24B is pressed, the lower mold 2
The second resin material 34 is injected into the cavity 28 formed between the resin material 4B and the cavity 28. That is, based on the rotation operation of the rotary plate 16 and the lifting and lowering operation of the movable plate 12, the upper molds 22A and 22B are moved to the lower mold 2.
4A and 24B alternately and simultaneously,
Two-color molded products are continuously molded in response to the rotation of the rotary disk 16.

Although not shown, when injecting the first resin material 32 into the cavity 26, normally a core is inserted into the cavity 26 with the cavity 26 separated from the protrusion 30 of the lower mold 24A. is inserted, and after cooling and solidifying the resin material 32, this core is removed, and then the upper molds 22, 22A, 22
The mold opening operation is performed from the lower mold 24A of B. By employing such a core, the first resin material 32 and the second resin material 34 can be reliably joined with a smooth joining surface.

In this embodiment, as shown in FIGS. 3 and 5, the cavity 26
Resin passages 36, 38 for guiding resin materials 32, 34 to the lower molds 24A, 28, respectively.
4B and their lower molds 24A, 24B on the lower surface plate 1
The resin passages 36, 3 are formed through the lower mold mounting plates 40, 42 for mounting on the
8 openings are opened in the side surfaces of the corresponding lower die mounting plates 40, 42. A first injection device 44 for injecting the first resin material 32
The nozzle 46 of the first resin material 32 is moved in the normal horizontal direction to touch the opening of the resin passage 36 opened on the side surface of the lower die mounting plate 40, and the first resin material 32 is Injection device 4
4 into the cavity 26 through the resin passage 36, and the nozzle 50 of the second injection device 48 for injecting the second resin material 34 is moved horizontally. , the nozzle is touched to the opening of the resin passage 38 opened on the side surface of the lower die mounting plate 42, and the second resin material 34 is injected into the second injection device 4.
8 into the cavity 28 through the resin passage 38.

Note that here, as shown in Figure 4,
When the upper molds 22, 22A, 22B are opened from the lower mold 24A, the first resin material 32 that is fixed to the upper mold 22 and raised together with the upper mold 22 includes:
Since the resin 52 of the sprue portion of the resin passage 36 (hereinafter simply referred to as sprue) is integrally provided in a state of protruding downward, a recess 54 for accommodating the sprue 52 is formed in the lower mold 24B. The mold closing/pressing operation of the upper mold 22 onto the lower mold 24B is prevented from being hindered.

In addition, in FIGS. 1 to 5, 56, 58
The upper molds 22A and 22B are respectively placed on the rotary plate 16.
This is an upper mounting plate for attaching to.

In a rotary injection molding machine having such a configuration, the nozzles 46, 50 of each injection device 44, 48 are placed horizontally at the openings of the resin passages 36, 38 which are opened on the sides of the lower mold mounting plates 40, 42. By moving in the direction, the nozzle is touched and the resin passages 36, 38 are connected to the cavities 26, 2.
8, the resin materials 32, 34 are injected into the upper molds 22, 22A, 22B.
When opening and closing the lower molds 24, 24A, 24B, the injection devices 44, 48 do not interfere with the upper molds 22, and therefore the nozzles 46, 50 of the injection devices 44, 48 are connected to the corresponding resin passages. Molding operations can be performed continuously while the nozzles remain in contact with the openings 36 and 38. In other words, like a conventional rotary injection molding machine, each time the mold is opened or closed, the injection device 44,
There is no need to perform the forward and backward operations of 48, thereby shortening the molding cycle and improving productivity.

In addition, resin material 3 is placed inside the cavities 26 and 28.
Resin passages 36, 38 for guiding the resins 2, 34 are opened on the sides of the lower mold mounting plates 40, 42, and the nozzles 46, 50 of the injection devices 44, 48 are opened in the lower mold mounting plates 40, 42. Closed resin passage 3
Since the nozzle can be touched to the openings of 6 and 38, regardless of the thickness of the mold pressed between the lower surface plate 10 and the movable plate 12, that is, the thickness of the lower molds 24A and 24B. Regardless, the nozzle touch surface (openings of the resin passages 36, 38) can always be set at a constant height, and therefore accurate nozzle touch can always be achieved.
Therefore, when replacing molds with different mold thicknesses (upper mold 22 and lower mold 24), it is possible to eliminate the need to adjust the height positions of the injection devices 44 and 48 one by one. Since the position of the injection device can be adjusted without any need, the support mechanism for the injection devices 44 and 48 can be greatly simplified.
Note that the height positions of the nozzle touch surfaces of the injection devices 44 and 48 only need to be constant for these injection devices 44 and 48, and there is no problem even if the height positions of the nozzle touch surfaces of these injection devices 44 and 48 are different from each other. do not have.

Furthermore, in this embodiment, since the resin passages 36, 38 are formed to penetrate the lower molds 24, 24A, 24B in the mold thickness direction, by replacing the lower mold mounting plates 40, 42, a general-purpose Another advantage is that the molds (upper mold 22 and lower mold 24) can be shared with a horizontal rotary injection molding machine.

One embodiment of the present invention has been described in detail above, but
This is a literal illustration, and the present invention is not limited to such specific examples, and various changes, modifications, improvements, etc. can be made based on the knowledge of those skilled in the art without departing from the spirit thereof. It goes without saying that it can be implemented in this manner.

(Effects of the invention) As is clear from the above explanation, the rotary injection molding machine according to the invention is provided with a resin passage passing through the lower mold to guide the resin material into the cavity of the mold. The passage is opened on the side of the lower mold mounting plate, and the nozzle of the injection device is made to touch the opening, so the nozzle touch surface of the injection device can be kept at a constant height regardless of the mold thickness. can be set in the position,
Therefore, accurate nozzle touch can be achieved at all times, and interference between the injection device and the upper mold can be avoided when the mold is opened and closed. Therefore, molds with different mold thicknesses can be replaced easily. In this case, it is not necessary to adjust the height position of the injection device one by one, and the supporting mechanism of the injection device can be greatly simplified. Also, the injection device can be moved forward each time the mold is opened and closed. - Eliminates the need for backward operation and performs molding operations continuously,
This makes it possible to significantly shorten the molding cycle.

[Brief explanation of the drawing]

FIG. 1 is a front view schematically showing an example of a rotary injection molding machine according to the present invention, and FIG. 2 is a cross-sectional view taken in FIG. 1. 3 to 5 are explanatory cross-sectional views for explaining the molding operation of the injection molding machine of FIG. 1, respectively. 10... lower surface plate (fixed plate), 12... movable plate,
16... Turntable, 20... Indexing machine, 22, 22
A, 22B... Upper mold, 24, 24A, 24B...
Lower mold, 26, 28... Cavity, 32, 34...
... Resin material, 36, 38 ... Resin passage, 40, 4
2... Lower mold mounting plate, 44, 48... Injection device, 4
6,50...nozzle.

Claims (1)

[Scope of Claim for Utility Model Registration] A plurality of pairs of molds are disposed on a fixed plate and a rotary plate disposed on a movable plate located above the fixed plate, and the movable plate is lowered. A rotary injection molding machine capable of simultaneously compressing a plurality of sets of molds at a plurality of rotational positions of the rotary disk by operation, comprising: a resin passageway for guiding a resin material into a cavity of the mold; is provided so as to pass through the lower mold attached to the fixed plate, and further provided so as to extend horizontally inside the lower mold mounting plate for attaching the lower mold to the fixed plate, and the lower mold mounting plate is provided so as to extend in the horizontal direction. An opening is formed in the side surface of the plate, and by horizontal movement of a predetermined injection device, a nozzle of the injection device is touched at the opening of the resin passage, and a resin material is injected into the cavity through the resin passage. A rotary injection molding machine characterized by being designed to press.