JPS62233215A - Injection molding machine - Google Patents

Abstract

PURPOSE:To eliminate a leak of resin and to facilitate an operation, by constituting the titled machine so that an injection equipment is fixed to a resin receiving port by connecting the same always with the resin receiving port and the same can be moved integrally with a central mold CONSTITUTION:Resin raw materials to be supplied through a hopper 44 of an injection equipment 40 are introduced within a barrel 46 through an opening 78, and sent in the direction of the tip of a screw 68 along with kneading of the resin raw materials by the rotating screw 68. At the time when a predetermined quantity of the resin material is accumulated at the tip of the barrel 46, a plunger 72 is moved forward by an action of oil pressure to be introduced through an oil pressure port 76 and the resin material is sent to a cavity of a mold by passing through a receiving port 38a of an intermediate platen 14 and a resin passage 38 from an injection port 40a of the injection equipment. The intermediate platen 14 and injection equipment 40 are unified by a bolt 50 and it does not happen that the resin leaks out through a connecting part between the intermediate platen 14 and injection equipment at the times of mold clamp and mold break. In addition to the above, as registration work between the injection port 40a of the barrel 46 and the receiving port 38a of the intermediate platen 14 is unnecessary, molding work can be performed extremely easily and swiftly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an injection molding machine used for molding resin materials such as synthetic resins. Specifically, in an injection molding machine equipped with a movable central mold and an outer mold that is installed so as to be able to come into contact with and separate from both the front and back sides of the central mold and define a molding cavity between the central mold and the central mold, the central mold This invention relates to an injection molding machine with an improved installation method for an injection device connected to a resin inlet.

[Prior Art] An injection molding machine is known in which a movable central mold and outer molds are arranged on both sides of the central mold, and a resin material is molded in a cavity defined between these molds. For example, Tokuko Sho 5
0-5216, JP-A-58-166030, JP-A-59-143624). Each of FIGS. 5 to 7 shows the configuration of such a conventional injection molding machine.

In FIGS. 5 to 7, a fixed plate 11112 is erected on the machine base 10, and an intermediate plate 14 and a movable plate 16 which are movable in the east direction relative to the plate surface of the fixed plate 12 are provided. The movable platen 16 is attached to a ram 20b of a mold clamping cylinder 20 fixedly installed on a cylinder platen 20a provided on the machine base 10.
It is moved in the left and right direction in FIG. 5 by the forward and backward movements of. 18 is a support member for the mold clamping cylinder 20. A column 22 is installed between the fixed platen 12 and the platen 20a, and the intermediate fi 14 and the movable platen 16 are guided by the column 22 and move.

The intermediate plate 14 is connected to a rod 24a of an intermediate plate moving cylinder 24 fixed to the fixed i12, and the rod 24a
By protruding and retracting, it is moved in the left-right direction in FIG. 5 in the same way as the movable platen 16.

Therefore, female molds 28.3 are provided on both the front and back sides of this intermediate board 14.
0 is fixed, and an outer mold (male mold in this example) 32.3 is provided on the intermediate plate 14 side of the fixed i12 and movable plate 16 respectively
4 is fixed. As shown in FIG. 6, a molding cavity 36, 36a is defined between the female mold and the male mold.

In this example, the female molds 28 and 30 and the intermediate plate 14 constitute a central mold.

A resin passage 38 for introducing the resin material into the cavity 36.36a is bored in the intermediate plate 14, and the injection port 40a of the injection device 40 approaches and separates from the resin receiving port 38a of the resin passage 38. It's bordering on possible.

This injection device 40 is installed on a slide base 42 installed on the machine base 10 so as to be movable back and forth. That is, a cylinder 43 for moving the injection device is fixed to the slide base 42, and the injection device 40 is moved back and forth by the protrusion and retraction of the rod of the cylinder 43. Further, when the screw shaft 42b extending in the width direction of the machine base 10 is rotated by operating the handle 42c, the injection device 40 moves in the left-right direction along the guide rail 42a on the machine base 10 together with the slide base 42. will be moved.

The injection device 40 includes a hopper 44 for receiving raw materials, and a screw (not shown) for kneading the resin material introduced into the device and extruding it by advancing it.
A hydraulic motor 48 for rotating a screw inside the barrel 46 is provided. Note that the tip of the barrel 46 serves as an injection port 40a of the injection device 40.

In the conventional injection molding machine having such a configuration, the male and female molds 28 to 3 are separated by the action of the ram 20b of the mold clamping cylinder 20.
4 is clamped, and then the cylinder 43 for moving the injection device is
, the injection port 4Oa of the injection device 40 is
A14 is brought into contact with the resin receiving port 38a, and then the resin material is injected from the injection device 40 into the cavity 36°36a through the resin passage 38, and the resin material is molded.After the molding is completed, the ram 20b is clamped. The intermediate mold 14 is moved to the left in the figure by retreating into the cylinder 20 and taking out the molded product from between the female mold 28 and the male mold 34, and protruding the piston rod 24a of the cylinder 24.
The injection device 40, which opens the space between the female mold 30 and the male mold 32 and similarly takes out the molded product, is slightly retracted by the action of the cylinder 43. Thereafter, the mold is clamped by performing the same procedure as described above, and injection molding is performed again.

[Problems to be Solved by the Invention] In the conventional injection molding machine described above, the injection port 40a of the injection device 40 is connected to the resin passage both during mold clamping and when opening the mold to take out the molded product. 38 intake ports 3
8a, resin leaks from the injection port 40a and the receiving port 38a, leading to waste of resin and deterioration of the working environment.

JP-A-59-143624 proposes providing an on-off valve in the resin passage 38 in order to solve the problem caused by the connection between the intermediate i 14 and the injection device 40 being disconnected every cycle. However, the valve must be opened and closed every cycle, making the operation complicated.

[Means for Solving the Problems] The injection molding machine of the present invention includes a movable central mold and outer molds arranged on both the front and back sides of the central mold. In an injection molding machine that performs molding by injecting resin, the injection device is always connected and fixed to the resin receiving port, and the injection device is configured to move integrally with the movement of the central mold.

[Function] In the injection molding machine of the present invention, the injection device is connected to the resin receiving port of the central mold both when the mold is clamped prior to the molding operation and when the mold is opened to take out the molded product. Since the work can be carried out with just one machine, there is no resin leakage, and the injection molding machine is extremely easy to operate.

[Examples] The present invention will be described in more detail below with reference to examples shown in the drawings.

FIG. 1 is a front view of an injection molding machine according to an embodiment of the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a right side view.

Also in the injection molding machine according to this embodiment, the machine base 1
0 through the cylinder platen 20a to the mold clamping cylinder 2.
0 is set. A movable mold 11116 is attached to the tip of the ram 20b protruding from the mold clamping cylinder 20, and a male mold 34 as an outer mold is fixed to the movable mold g116. Both ends are held by the cylinder platen 20a and the fixed platen 12.

The movable fi 16 and the intermediate plate 14 are slidable along the column 22.

Female molds 28 and 30 are fixed to both surfaces of the intermediate board 14, and the female mold 28 and the male mold 34 are fitted together, and the female mold 30 and the male mold 32 are fitted together. The male die 32 is fixed to a stationary i12, and the stationary l1112 is fixedly erected on the machine base 10 with bolts or the like.

Thus, in one embodiment, the barrel 4 of the injection device 40
6 is connected and fixed to the intermediate fi 14 by a pole 50, so that it moves integrally with the movement of the intermediate fi 14.

In this embodiment, the intermediate plate moving cylinder 24 is fixed to the machine base lOE via a support member 24b on the opposite side from the mold clamping cylinder 20.
At the tip of the piston rod 24a of No. 6, a holder 52 is fixedly disposed diagonally as shown in FIG.

An injection bag 2i40 is provided on the upper end side of the holder 52 in the diagonal direction.
A hydraulic motor 48 is fixed, and a tie rod 54 connecting the intermediate l1114 and the holder 52 is connected to one lower end of the holder 52. Therefore, when the intermediate plate moving cylinder 24 is operated, the intermediate plate is connected to the injection device 40 via the boulder 52. 14 are moved together.

In the injection bag M40, the tip of the barrel 46 is connected to the intermediate plate 14.
50 is fixed to the resin receiving port 38a of the resin receiving port 38a. 26 is an injection cylinder for moving the screw 68 back and forth within the barrel 46, and the piston for the injection cylinder 68 that is integrated with the screw 68 is connected to the hydraulic motor 4.
It is connected to the shaft of No. 8 by a spline. 44 is a hopper for feeding pellets.

The reference numeral 56 is an extrusion device for extruding and demolding the molded product from the male die 32, and a support plate 60. A push-out plate 64 is fixed to the support plate 60, attached to a hydraulic cylinder 62, and a rod 62a of the hydraulic cylinder 62, and moved toward and away from the stationary plate 12 by the operation of the cylinder 62. The extrusion pin 66 is attached to the extrusion plate 64 in the horizontal direction, and has an extrusion pin 66 whose tip has a length such that it can protrude from the mold surface of the male mold 32. That is, when the rod 62a is projected from the cylinder 62, each push-out pin 66 moves toward the male die 3 as the push-out plate 64 moves.
The molded product protruding from the second mold surface and in close contact with the mold surface is extruded.

Although not shown, an extrusion device similar to the extrusion device 56 is also installed inside the ram 20b.
An extrusion pin (not shown) of the extrusion device in b protrudes from the mold surface of the male mold 34 and is configured to extrude and demold the molded product that is in close contact with the mold surface of the male mold 34. .

FIG. 4 is a longitudinal sectional view showing the internal structure of another embodiment of the injection device 40.

As shown in the figure, a screw 68 is rotatably inserted into a barrel 46 that is fixed to a holder 52 that moves by the action of the intermediate plate moving cylinder 24, and is movable back and forth. A rotor (not shown) of a hydraulic motor 48 is connected to the end side via a shaft 70. Note that the injection cylinder 26 portion on the rear end side of the barrel 46 has a double barrel structure, and the plunger 72, which is held rotatably while penetrating the shaft 70t, is inserted in the front-rear direction 2.
The shaft 70 and the screw 68 integrated with the shaft 70 are moved forward and backward together with the hydraulic motor 48 by the hydraulic pressure introduced from the hydraulic boats 74 and 76 at the locations. Note that the plunger 72
The rear end portion may be held without bending by a movable holder 52a as shown by the two-dot chain line.

In this injection device 40, the resin raw material supplied from the hopper 44 is introduced into the barrel 46 from the open lower 8, is kneaded by the rotating screw 68, and is sent toward the tip, so that a predetermined amount of the resin material is poured into the barrel 46. When the liquid is accumulated at the tip, the plunger 72 is moved forward by the action of the hydraulic pressure introduced from the hydraulic boat 76, and as a result, the resin material flows from the injection port 40a of the injection device through the receiving port 38a of the intermediate plate 14 and the resin passage 38, and the resin material flows into the gold. sent to the mold cavity.

In the injection molding machine of this embodiment, the intermediate plate 14 and the injection device 40 are integrated with bolts 50, etc., and resin leaks from the connection between them both when the mold is closed and when the mold is opened. I never take it out. In addition, the injection port 40 of the barrel 46
Since there is no need for positioning work between a and the receiving opening 38a of the intermediate plate 14, the molding work can be performed extremely easily and quickly.

In this embodiment, as shown in FIG. 3, the holder 52 is arranged diagonally, and the injection device 40 is arranged above the side of the injection molding machine. Therefore, the injection device 40 does not interfere with the work when opening the mold, replacing the mold, etc., and it is possible to perform the work with high efficiency.

FIG. 8 is a sectional view of essential parts showing the configuration of an injection molding machine according to a different embodiment of the present invention.

That is, in the embodiment apparatus shown in FIGS. 1 to 4,
Although only one injection device was provided, in the embodiment shown in FIG.
B is provided. And each injection device 40
Two series of resin passages 38A and 38B are provided for guiding the resin from A and 40B to the cavities, and the resin material from one injection device 4OA passes through the passage 38A to one cavity 36A, and the other. Injection bag 2t4O
The resin material from B is introduced into the other cavity 36B through passageway 38B, allowing molded articles of different colors, shapes, or materials to be molded simultaneously in a single injection molding operation.

Therefore, for example, molded products of different colors or of different materials can be manufactured in parallel. It is also possible to simultaneously mold the container body and lid portion of the container as one set.

The rest of the structure of the injection molding machine shown in FIG. 8 is the same as that of the above embodiment, and the same members are given the same reference numerals and the explanation thereof will be omitted. Although the extrusion device is not shown in the injection molding machine of FIG. 8, it is clear that an extrusion device may be provided in this embodiment as well.

FIG. 9 is a sectional view of essential parts showing the configuration of an injection molding machine according to still another embodiment of the present invention.

In this embodiment, two injection devices 40A and 40B are installed as in the embodiment shown in FIG. 8, and resin passages 38A and 38B guide the resin material injected from them.
The two converge at the center of the intermediate board 14 to form a cross-shaped resin passage. This cross-shaped intersection has a three-way valve 8.
0 is set. In addition, each of the passages 38A and 38B is branched into a T-shape near the reception port 1, and one of the branch passages continues straight and opens onto the board surface of the intermediate board 14. Valves 82 and 84 are closed.

In the apparatus of the embodiment shown in FIG. 9 configured in this way, only the resin material from one injection device, for example 4OA, can be selectively supplied to the cavities 36A and 36B. Therefore, according to the injection molding machine according to this embodiment, both injection devices 40
By inserting resin raw materials of different colors or materials into A and 40B and switching the three-way valves 80, 82, 84, it is possible to quickly switch to manufacturing a molded product of a different color or material. In other words, in an injection molding machine equipped with only one injection device, when supplying materials of one different color or different types of materials,
The finished product cannot be molded until all the resin material in the barrel and resin passage of the injection device is replaced.
It used to take a long time to switch, but by installing two injection devices like this, it is possible to mold with different colors or types of materials without having to replace the resin materials in the barrel and passage. can.

In this embodiment, as described above, the resin passages 38A and 38B in the intermediate board 14 are branched into a T-shape, and the three-way valves 82 and 84 are installed at this T-shaped branch. Therefore, when a resin material is supplied into the cavity from one passage, for example, 38A, the other three-way valve 84 selects the flow path so as to short-circuit the resin out of the passage. It can be avoided that the material remains for a long time.

FIG. 10 is a sectional view of essential parts showing the configuration of an injection molding machine according to still another embodiment of the present invention. In this embodiment, the three-way valves 80, 82, and 84 in the embodiment shown in FIG. ! 114, and intersect in the shape of a cross at this central portion. In the injection molding machine according to the embodiment shown in FIG. 10, resin raw materials colored in different colors are introduced from two injection devices, and while mixing the two colored materials, each cavity 36A,
36B, and two-color mixing molding can be easily performed.

It is clear that an extrusion device may be provided in the embodiments shown in FIGS. 9 and 10 in the same manner as in the above embodiments. The rest of the structure of the embodiment shown in FIGS. 9 and 10 is the same as that of the above embodiment, and the same members are given the same reference numerals and their explanations will be omitted.

In the present invention, three or more injection devices may be installed, and in the above embodiment, the female mold 28.
30 are respectively fixed to the intermediate plate 14, but in the present invention, as described in Japanese Patent Publication No. 5216/1983, the intermediate plate 14 is omitted and the pair of female molds 28 and 30 are directly fixed. The injection device i! is connected to the receiving port of the resin passage provided in this connected body. The injection port of t40 may be communicated with each other, or the female mold 28.3o may be manufactured in advance by casting, forging, cutting, etc., without using the connecting method.

In addition, in the above embodiment, in FIG. 3, ``hopper 44'' and injection device ! 40 to the upper right, tie rod 5
4 is placed at the lower left and the holder 52 is placed diagonally.
It is also possible to arrange the holder 52 horizontally by placing o at the center in the vertical direction, or to change the design as appropriate.

Also, intermediate? It is also possible to appropriately heat the resin passage 38 inside 1t14 with a heater (not shown) to serve as a pot runner and improve the flow of the resin.

[Effects of the Invention] As detailed above, in the injection molding machine of the present invention, the injection device moves integrally with the central mold, and there is no leakage of resin material when the mold is clamped or opened. Moreover, it is extremely easy to operate, and injection molding operations can be carried out efficiently.

[Brief explanation of drawings]

Fig. 1 is a front view of an injection molding machine according to an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a right side view thereof, and Fig. 4 is a longitudinal section showing one embodiment of an injection device 4o. Fig. 5 is a front view showing the conventional example, Fig. 6 is a rotational view, Fig. 7 is a right side view of the same, Figs. FIG. 3 is a cross-sectional view of essential parts of an injection molding machine according to a different embodiment. lO...machine base, 12...fixed plate, 14
...Middle board, 16...Movable board. 20...Mold clamping cylinder, 20a...Cylinder platen. 20b... Ram, 24... Intermediate plate moving cylinder, 26... Injection cylinder, 28.30... Female mold. 32.34...Outer mold (male mold), 38.38A, 38B...Resin passage, 40...Injection device, 48...Hydraulic motor, 56... Molded product extrusion device.

Claims (1)

[Claims] (1) A movable central mold and a pair of outer molds that are installed facing each other so as to be able to come into contact with and separate from both the front and back sides of the central mold, and define a molding cavity between the central mold and these molds. In an injection molding machine equipped with a tightening device and an injection device connected to the resin introduction port of the central mold, the injection device is installed so as to be movable in the moving direction of the mold, and the injection port of the injection device is connected to the resin introduction port of the central mold. An injection molding machine characterized by being connected and fixed to a central resin receiving port.