CN114905697A

CN114905697A - Injection molding machine

Info

Publication number: CN114905697A
Application number: CN202210097449.9A
Authority: CN
Inventors: 菅野直树; 深山寿秀
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2021-01-28
Filing date: 2022-01-27
Publication date: 2022-08-16
Also published as: JP2022115773A; JP6938803B1; JP2022115787A

Abstract

The invention provides an injection molding machine capable of improving the maintenance operability. An injection molding machine (1) injects a molding material into a mold (104) to perform molding, and is provided with a mold supporting member (41) that supports the mold (104), wherein the mold supporting member (41) has one or more heat medium flow paths (P1, P2) that communicate with a mold-side flow path and that flow a heat medium that adjusts the temperature of the mold (104), and wherein an inlet and an outlet of at least one of the heat medium flow paths (P1, P2) are present on one of the two sides of the mold supporting member (41) that are located across the mold (104).

Description

Injection molding machine

Technical Field

The present application claims priority based on Japanese patent application No. 2021-28/2021. The entire contents of this Japanese application are incorporated by reference into this specification.

The present invention relates to an injection molding machine having a heat medium flow path for allowing a heat medium to flow in a mold when the temperature of the mold of a mold device is adjusted by injection molding.

Background

When a molding material is injected into a mold apparatus to perform molding, it is necessary to adjust the temperature of the mold apparatus to an appropriate temperature in each step. Therefore, a mold-side flow path through which a heat medium such as oil, water, or other liquid flows is formed in the mold of the mold apparatus.

On the other hand, in the injection molding machine, a heat medium flow path communicating with the mold-side flow path is provided in the mold supporting member to which the mold is attached. The heat medium flows into a heat medium flow path of a mold supporting member of the injection molding machine from a temperature regulator such as an external heat exchanger, passes through a mold-side flow path of the mold, flows out of the mold supporting member of the injection molding machine, and flows through the temperature regulator to circulate.

As an example of this, in injection blow molding, a so-called injection blow molding machine, which is an injection molding machine including a rotating shaft portion as the mold supporting member that rotates while supporting an intermediate mold disposed between a fixed mold and a movable mold, can be used. As such an injection molding machine, there is an injection molding machine described in patent document 1. The rotation shaft portion may be provided with a heat medium flow path communicating with the mold-side flow path of the intermediate mold.

Patent document 1: japanese patent laid-open publication No. 2018-167579

In the mold supporting member described above, the inlet of the heat medium flow path may be provided on one of the two sides across the mold, and the outlet of the heat medium flow path may be provided on the other of the two sides.

In this case, when the heat medium flow path is maintained, it is necessary to operate both sides where the outlet port and the outlet port are present, and the operability cannot be said to be good.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object thereof is to provide an injection molding machine capable of improving the operability of maintenance.

An injection molding machine capable of solving the above problems injects a molding material into a mold to perform molding, and includes a mold supporting member that supports the mold, the mold supporting member having one or more heat medium flow paths that communicate with a mold-side flow path and through which a heat medium for adjusting a mold temperature flows, at least one of an inlet and an outlet of the heat medium flow path being present on one of both sides of the mold supporting member across the mold.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the injection molding machine, the operability of maintenance can be improved.

Drawings

Fig. 1 is a sectional view showing an injection molding machine according to an embodiment of the present invention.

Fig. 2 is a front view schematically showing an intermediate mold, an intermediate mold support frame, and a rotation shaft portion, which adjust the flow of a heat medium for adjusting the temperature of the intermediate mold of the mold device in the injection molding machine of fig. 1.

Fig. 3 is a front view schematically showing an intermediate mold, an intermediate mold support frame, and a rotation shaft in the injection molding machine according to the reference example, in which a heat medium for adjusting the temperature of the intermediate mold of the mold apparatus flows.

Fig. 4 is a cross-sectional view along the axial direction of the rotating shaft portion showing one end portion side of each of the rotating shaft portion and the modification of fig. 3.

Fig. 5 is a cross-sectional view along the axial direction of the rotation shaft portion showing one end portion side of the rotation shaft portion provided in the injection molding machine according to another embodiment.

Fig. 6 is the same sectional view showing a state in which the one end-side shaft body shown in fig. 5 is displaced in the axial direction.

Fig. 7 is a cross-sectional view along the axial direction of the rotation shaft portion showing one end portion side of the rotation shaft portion provided in the injection molding machine according to still another embodiment.

Fig. 8 is a partially enlarged side view showing a mold opening state of the mold device attached to the injection molding machine 1 of fig. 1 and a sectional view taken along a line II-II thereof.

Fig. 9 is a partially enlarged side view showing a clamped state of a mold apparatus attached to the injection molding machine 1 of fig. 1 and a sectional view taken along a line II-II thereof.

Description of the symbols

1-injection molding machine, 2-base frame, 21-injection device, 22-cylinder, 22 a-supply port, 22 b-nozzle, 22 c-water-cooled cylinder, 23-screw, 24-heater, 25-motor box, 26-moving device, 26 a-slide base, 26 b-guide, 27-hydraulic pump, 28-pump working motor, 29-hydraulic cylinder, 31-mold clamping device, 32 a-fixed platen, 32 b-movable platen, 32 c-intermediate mold support frame, 32 d-connecting rod, 32 e-guide, 33-mold clamping mechanism, 34-back platen, 35-mold clamping motor, 36-motion conversion mechanism, 36 a-screw shaft, 36 b-nut, 37-toggle mechanism, 37a to 37 c-links, 37 d-crosshead, 38-die thickness adjusting motor, 41-a rotating shaft portion (die supporting member), 42 a-one end portion, 42 b-the other end portion, 43-a shaft main body portion, 44a to 44 d-an annular portion, 45 a-an inner flow path dividing member, 45 b-an outer flow path dividing member, 46-a piping member, 47a, 47 b-an open ring, 48-a displacement restricting member, 48 a-an outer peripheral edge portion, 49 a-a cover member, 50-an elastic member, 51-a bolt, 52-an inner contact member, 61-an intermediate die moving mechanism, 61 a-a hydraulic cylinder, 61 b-a piston rod, 62-split die opening and closing mechanism, 62 a-a piston rod, 62 b-hydraulic cylinder, 63a, 63 b-split mold connecting member, 101-mold device, 102-fixed mold, 102 a-fixed side cavity, 103-movable mold, 103 a-movable side cavity, 103 b-split mold, 104-intermediate mold (mold), 104 a-male mold, Fa, Fb-axial force, P1, P2-heat medium flow path, P1in, P2 in-inflow side flow path, P1out, P2 out-outflow side flow path, PF-preform, MP-molded article.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The injection molding machine 1 illustrated in fig. 1 roughly includes: an injection device 21 that melts the molding material and injects the molding material into the mold device 101 by rotation and forward movement of a screw 23 disposed inside and heating of a heater 24 disposed around; a moving device 26 for moving the injection device 21 forward and backward with respect to the mold device 101; and a mold clamping device 31 having a fixed platen 32a, a movable platen 32b, and an intermediate mold support frame 32c, and opening and closing the mold device 101 between a mold clamping state and a mold opening state.

The injection molding machine 1 is also called an injection blow molding machine, and is used for injection blow molding as follows: after a preform is molded by injecting a molding material into an injection molding cavity, a fluid such as gas is supplied into the blow molding cavity to expand the preform, thereby producing a molded article.

As a mold device 101 for partitioning the injection molding cavity and the blow molding cavity in a clamped state, a mold device having a fixed mold 102, a movable mold 103, and an intermediate mold 104 disposed between the fixed mold 102 and the movable mold 103 is used. In the clamped state, the injection molding cavity is partitioned between the fixed mold 102 and the intermediate mold 104, and the blow molding cavity is partitioned between the movable mold 103 and the intermediate mold 104.

In the mold apparatus 101, the fixed mold 102 is attached to the fixed platen 32a side, and the movable mold 103 is attached to the movable platen 32b side. The intermediate mold 104 of the mold device 101 is attached to the rotation shaft 41, which is a mold supporting member provided in the intermediate mold supporting frame 32c, and is rotated by the rotation shaft 41. Details of the mold clamping device 31 having the fixed platen 32a, the movable platen 32b, and the intermediate mold support frame 32c will be described later.

(Heat medium flow path)

The mold such as the intermediate mold 104 of the mold apparatus 101 needs to be adjusted to an appropriate temperature in each step of injection molding using the injection molding machine 1. Therefore, the intermediate mold 104 is provided with a mold-side flow path through which a liquid such as oil or water or another heating medium such as water fed from the injection molding machine 1 flows and which returns the heating medium to the injection molding machine 1 after flowing.

On the other hand, on the injection molding machine 1 side, at least one, for example, two heat medium flow paths P1, P2 indicated by the solid and dotted arrows shown in fig. 2 are provided in the rotary shaft 41 to which the intermediate mold 104 is attached and which supports the intermediate mold 104. The heat medium flow path provided in the rotating shaft 41 functions as the mold-side flow path for feeding the heat medium adjusted to a predetermined temperature by a temperature regulator such as an external heat exchanger not shown to the intermediate mold 104, and flows the heat medium after passing through the mold-side flow path and returns the heat medium to the temperature regulator.

Note that, although the heat medium flow paths may be provided in the fixed mold 102 and the movable mold 103 of the mold apparatus 101 other than the intermediate mold 104, the description will be made here, as an example, with attention being paid to the heat medium flow paths P1 and P2 for flowing the heat medium through the intermediate mold 104 in the mold included in the mold apparatus 101. In this embodiment, the mold supporting member having the heat medium flow path is a rotary shaft 41 provided in the injection molding machine 1 as the injection blow molding machine. However, in the present invention, although not shown, a heat medium flow path provided in a mold supporting member other than the rotating shaft portion 41, for example, a mold supporting member not provided in an injection molding machine of an injection blow molding machine, may be used as a target.

Here, the rotating shaft 41 provided with the heat medium flow paths P1, P2 extends in the axial direction (the left-right direction in fig. 2) parallel to the mold width direction and has both

end portions

42a, 42b projecting outward of the intermediate mold 104 in the axial direction. The both

end portions

42a and 42b are supported by bearings or the like so as to be rotatable with respect to the intermediate mold support frame 32c and extend further outward than the intermediate mold support frame 32c in the axial direction.

Here, as in the reference example shown in fig. 3, it is also conceivable to arrange inlets and outlets of the heat medium flow paths P1 and P2 at both

end portions

242a and 242b of the rotation shaft portion 241 on both sides across the intermediate mold 104. Thus, the heat medium flow paths P1 and P2in fig. 3 are provided so as to extend over both

end portions

242a and 242 b. More specifically, the heat medium flow paths P1 and P2 allow the heat medium flowing in from an inlet provided at one end 242a or the other end 242b to flow toward the one end 242a or the other end 242b of the rotating shaft 241, to flow toward the other end 242b or the one end 242a after passing through the die-side flow path, and to flow out from an outlet provided at the other end 242b or the one end 242 a.

However, in the heat medium flow paths P1 and P2 of fig. 3, when the heat medium flow paths P1 and P2 are to be maintained, it is necessary to disassemble the both

end portions

242a and 242b of the injection molding machine to clean the heat medium flow paths P1 and P2, for example, at both sides where the both

end portions

242a and 242b are present. Therefore, the reference example cannot be said to be excellent in operability.

In contrast, in this embodiment, as shown in fig. 2, the heat medium flow paths P1 and P2 are provided such that the inlet and outlet of each of the heat medium flow paths P1 and P2 are present at one end 42a of the two

ends

42a and 42b of the rotation shaft 41 on both sides across the intermediate mold 104.

Thus, in the injection molding machine 1, the maintenance work of the heat medium flow paths P1 and P2 can be performed only on one side, which is the side where the inlet and outlet of the heat medium flow paths P1 and P2 are present. This can improve the workability of maintenance.

In the illustrated example, all of the inlets and outlets of the plurality of heat medium flow paths P1 and P2 are present at the one end portion 42 a. In this way, when all the inlets and outlets of the heat medium flow paths P1 and P2 are concentrated on the side of the one end portion 42a, for example, the rotary motor and other rotary driving mechanisms of the intermediate mold 104 can be disposed on the other end portion 42b, and the device can be downsized. The rotation driving mechanism may be provided at the one end 42a where the inlet and outlet of the heat medium flow paths P1 and P2 are present, but in this case, the protruding amount of the one end 42a is increased, and therefore, it is preferably provided at the other end 42 b.

However, when there are a plurality of heat medium flow paths, the inlet and outlet of at least one of the heat medium flow paths may be present on one side. This improves the operability of maintenance of the heat medium flow path having the inlet and the outlet provided on one side. The other heat medium channel may be a channel in which an inlet port is present on one side and an outlet port is present on the other side.

In the case where a plurality of heat medium channels are provided, the inlet and outlet of another heat medium channel may be provided on the side opposite to the side where the inlet and outlet of a specific one of the heat medium channels are provided. That is, when one heat medium channel is observed, the inflow port and the outflow port of the heat medium channel may be present on either side of the mold.

Further, although at least the inlet and the outlet of the heat medium flow paths P1 and P2 are provided at the one end 42a, the flow path portions of the heat medium flow paths P1 and P2 other than the inlet and the outlet may be present at the other end 42 b.

Of the two

end portions

42a and 42b of the rotation shaft 41, the end portions provided with the inlet and outlet ports of the heat medium flow paths P1 and P2 may be replaced with the illustrated end portions. In the end portion 42a and the end portion 42b described here, the inlets and outlets of the heat medium flow paths P1 and P2 can be located on the side of the end portion 42b, and the rotation drive mechanism described above can be provided in the end portion 42 a.

The inlet and outlet of the heat medium flow paths P1 and P2 are not limited to the end 42a, and may be provided at a portion located further inward in the mold width direction than the end 42a, as long as they are located at one of the two sides of the rotary shaft 41 across the middle mold 104.

As shown in fig. 2, the heat medium channels P1 and P2 include an inlet and an outlet provided at the one end 42a of the rotation shaft 41, inlet-side channel portions P1in and P2in that flow from the inlet toward the one end 42a and are guided to the die-side channel of the middle die 104 in the heat medium channels P1 and P2, and outlet-side channel portions P1out and P2out that flow the heat medium having passed through the die-side channel toward the one end 42a and are guided to the outlet, respectively. The heat medium flowing out of the rotation shaft 41 through the outlet is sent to an external temperature controller and adjusted to a predetermined temperature, and then flows into the rotation shaft 41 through the inlet and circulates therebetween.

When the mold supporting member is the rotation shaft 41, the heat medium flow paths P1 and P2 are provided on the side of the one end 42a of the rotation shaft 41, and therefore the one end 42a can have a configuration as shown in a cross-sectional view in fig. 4 (a) or fig. 4 (b), for example. The rotation shaft 41 has a shaft body 43 extending over both

end portions

42a and 42b and driven to rotate. In fig. 4 (a) and 4 (b), annular portions 44a to 44d constituting at least a part of the inflow side flow paths P1in and P2in and the outflow side flow paths P1out and P2out of the heat medium flow paths P1 and P2 are provided around the shaft body portion 43 on the side of the one end 42a of the rotation shaft portion 41.

The annular portions 44a to 44d are formed at axially different positions in the one end portion 42a, and although not shown, a rotary shaft seal member such as an O-ring for preventing the heat medium from leaking out can be provided between them.

In this embodiment, since the rotation shaft 41 has two heat medium flow paths P1 and P2, a total of four annular portions 44a to 44d are arranged in the axial direction at the one end 42a of the inflow side flow path portions P1in and P2in and the outflow side flow path portions P1out and P2out of the heat medium flow paths P1 and P2, respectively. However, the number of the heat medium flow paths may be one, three or more, and the number of the annular portions may be changed accordingly.

Since the annular portions 44a to 44d are defined in the one end portion 42a of the rotating shaft portion 41, the one end portion 42a includes an inner flow passage defining member 45a fixedly provided to the shaft body portion 43 and a cylindrical outer flow passage defining member 45b disposed so as to surround the inner flow passage defining member 45 a. The annular portions 44a to 44d are defined between an inner flow passage defining member 45a that rotates together with the shaft body portion 43 when the rotary shaft portion 41 is rotationally driven and an outer flow passage defining member 45b that is fixed to the intermediate mold support frame 32c or the like on the outer circumferential side thereof and is stationary.

Although not shown in detail, the outer flow path dividing member 45b is provided with, for example, flow path portions that communicate the respective annular portions 44a to 44d with the respective piping members 46 that are provided on the outer peripheral side thereof and serve as inlets or outlets. The inner flow passage partition member 45a and the shaft body 43 are provided with flow passage portions that connect the annular portions 44a to 44d and the mold-side flow passages.

However, the circumferential lengths of the annular portions 44a to 44d may differ from each other due to the provision of the above-described rotary shaft seal member between the annular portions 44a to 44d in the axial direction. In the illustrated embodiment, of the plurality of annular portions 44a to 44d, the annular portion located on the axially outer side has a longer circumferential length than the annular portion located on the axially inner side. That is, the circumferential lengths of the plurality of annular portions 44a to 44d are longer in the order of the annular portion 44d located on the innermost side in the axial direction, the annular portion 44c located adjacent to the outer side thereof, the annular portion 44b further adjacent to the outer side thereof, and the annular portion 44a located on the outermost side thereof. The circumference represents a length measured on the flow path center axis passing through the center of the flow path cross section of the annular portions 44a to 44d orthogonal to the flow direction of the heat medium.

The annular portions 44a to 44d having different circumferential lengths can be formed by forming the outer circumferential surface of the inner flow passage partitioning member 45a and the inner circumferential surface of the outer flow passage partitioning member 45b into stepped shapes having outer diameters or inner diameters that increase outward in the axial direction. Further, a cylindrical cover member 49 having a bottom is attached to the one end portion 42a so as to cover the outer end surface of the outer flow passage dividing member 45b in the axial direction, on the outer side in the axial direction than the outer flow passage dividing member 45 b. In fig. 4 (a), the annular portion 44a located on the outermost side in the axial direction communicates with the inside of the cover member 49 located further outside thereof, and the inside of the cover member 49 is also filled with the heat medium flowing through the outflow side flow path portion P2out of the heat medium flow path P2. On the other hand, in fig. 4 (b), the annular portion 44a is closed by the end face of the bottomed cylindrical cover member 49a, and the heat medium does not flow into the cover member 49 a.

At this time, for example, when the power supply of the temperature regulator is turned on and the heat medium such as the heating agent is caused to flow by the required internal pressure in the heat medium flow paths P1 and P2, an axial force Fb axially directed toward the other end portion 42b side acts on the inner flow path dividing member 45a and the shaft body portion 43 as indicated by black arrows in fig. 4 (a) due to the difference between the internal pressure in the annular portion 44a having a large volume and the inner portions of the cover member 49 in fig. 4 (a) and the internal pressures in the annular portions 44b to 44d having a smaller volume than the internal pressure. Thereby, the inner flow passage dividing member 45a and the shaft body 43 are displaced toward the other end 42b in the axial direction. At this time, as shown in fig. 2, of the split rings 47a and 47b positioned between the intermediate die 104 and the intermediate die support frame 32c, the split ring 47b on the other end portion 42b side is pressed by the intermediate die support frame 32c and worn, and the generated metal powder may adhere to the molded article.

On the other hand, in fig. 4 (b), due to the action of the internal pressure on the heat medium flow paths P1, P2, as indicated by the white arrows in fig. 4 (b), an axial force Fa is generated in a direction (direction toward the one end 42a in the axial direction) in which the inner and outer flow

path dividing members

45a, 45b, the inner and outer diameters of which increase outward in the axial direction, are pulled away from each other. Accordingly, the inner flow passage dividing member 45a and the shaft body 43 are displaced toward the one end 42a in the axial direction by the axial force Fa. As a result, split ring 47a on the side of one end portion 42a shown in fig. 2 may be worn.

To cope with this, in the embodiment shown in fig. 5, a displacement regulating member 48 such as a plate for regulating the amount of displacement in the axial direction of the shaft body 43 is provided in a manner to be connected to the axially outer end surface of the inner flow passage partitioning member 45a by a step portion which is added to the axially outermost side of the inner flow passage partitioning member 45a, as compared with the embodiment shown in fig. 4. The cover member 49 is provided axially outward of the outer flow passage dividing member 45 b.

The plate-like displacement restricting member 48 is located inside the cover member 49, and is disposed between the cover member 49 and the outer end surface of the outer flow passage partition member 45b, particularly in the outer peripheral edge portion 48a that protrudes to the outer peripheral side of the inner flow passage partition member 45 a. Thus, when the inner flow passage dividing member 45a and the shaft main body portion 43 are displaced in the axial direction, the displacement regulating member 48 abuts against the cover member 49, or the outer peripheral edge portion 48a abuts against the outer end surface of the outer flow passage dividing member 45b, whereby the amount of displacement in the axial direction of the shaft main body portion 43 connected to the displacement regulating member 48 is regulated. However, the displacement regulating member 48 is not limited to a plate-like member having the outer peripheral edge portion 48a in contact with the outer end surface of the outer flow passage partition member 45b as shown in the figure, as long as it can regulate the amount of displacement in the axial direction of the shaft body portion 43.

When the axial force Fa in the direction of the open arrow in fig. 5 is applied due to the internal pressure of the heat medium flow paths P1 and P2 as described above, the displacement restricting member 48 abuts against the cover member 49, thereby preventing further displacement of the inner flow path dividing member 45a and the shaft body portion 43 to the outside in the axial direction. As a result, abrasion of

split rings

47a and 47b and generation of metal powder associated therewith can be suppressed.

However, for example, when the power supply of the temperature regulator is turned off and the temperature of the intermediate mold 104 and the rotation shaft 41 drops, an axial force Fb in a direction indicated by a black arrow in fig. 6 opposite to the axial force Fa is applied to the inner flow passage dividing member 45a due to thermal shrinkage of the shaft body 43. At this time, as shown in fig. 6, when the displacement restricting member 48 reaches a position where it abuts against the outer end surface of the outer flow passage partitioning member 45b in the outer peripheral edge portion 48a and the axial force Fb acts, there is a possibility that a connection portion such as a bolt between the displacement restricting member 48 and the inner flow passage partitioning member 45a may be damaged.

In contrast, in the embodiment shown in fig. 7, the connection portion between the inner flow passage partition member 45a and the displacement restricting member 48 includes an elastic member 50 that resists an axial force Fb in a direction in which the displacement restricting member 48 is pulled away from the inner flow passage partition member in the axial direction. More specifically, in this example, the connection portion between the inner flow passage dividing member 45a and the displacement restricting member 48 includes a bolt 51 that penetrates the plate-shaped displacement restricting member 48 and is screwed into the shaft main body portion 43, and an elastic member 50 such as a coil spring into which the shaft portion of the bolt 51 is inserted and which is interposed between the head portion and the displacement restricting member 48. Here, an inner contact member 52 is provided so as to match the inside of the cover member 49, has a bottomed tubular shape having an inner and outer diameter smaller than the cover member 49, and generates displacement restriction by the displacement restricting member 48 with respect to the outer flow passage dividing member 45 b.

In fig. 7, when an axial force Fa toward the one end portion 42a in the axial direction acts, as shown in fig. 7 (a), the displacement restricting member 48 abuts against the opening end portion of the inner contact member 52 at the outer peripheral edge portion 48a, thereby preventing further displacement of the inner flow path dividing member 45a and the shaft body portion 43. The inner contact member 52 is not limited to the cylindrical member shown in the drawings as long as it can restrict the inner flow passage dividing member 45a and the shaft body portion 43 when the axial force Fa acts.

On the other hand, when an axial force Fb in the direction opposite to the axial force Fa acts, the displacement restricting member 48 abuts against the outer flow passage partition member 45b, and when the axial force Fb further acts, the inner flow passage partition member 45a and the shaft body portion 43 are separated from the displacement restricting member 48, and the elastic member 50 is sandwiched between the head portion of the bolt 51 and the displacement restricting member 48 and deformed so as to counteract the axial force Fb, as shown in fig. 7 (b). This can effectively prevent damage to the connection portion between the displacement restricting member 48 and the inner flow passage dividing member 45 a.

Since the space between the inner contact member 52 and the outer flow passage dividing member 45b is changed and the displacement of the shaft body 43 regulated by the displacement regulating member 48 is adjusted, a plate-like spacer or spacer, for example, can be provided between the inner contact member 52 and the cover member 49, but illustration thereof is omitted.

Further, it is also conceivable that the displacement restricting member 48, the elastic member 50, or the like is provided on the other end portion 42b side as a countermeasure against the axial forces Fa and Fb. However, as described above, the rotary drive mechanism of the intermediate die 104 may be disposed on the other end portion 42b side, and in this case, metal powder generated by abrasion may enter the rotary drive mechanism in a configuration to cope with the axial forces Fa and Fb. From this viewpoint, as in the illustrated embodiment, it is preferable to provide the displacement restricting member 48, the elastic member 50, and the like on the one end portion 41a side.

The interior of the cover member 49 (or the interior of the inner contact member 52) can be filled with lubricating oil. This enables the displacement restricting member 48 to slide smoothly inside the cover member 49. Even if metal powder is generated in the cover member 49 by the sliding movement of the displacement restricting member 48, the metal powder remains in the interior, and therefore the adhesion of the metal powder to the molded article is suppressed.

(mold clamping device)

The intermediate mold support frame 32c having the rotary shaft 41 as described above is included in the mold clamping device 31 as one of the mold holding mechanisms 32 for holding the mold device 101. The mold clamping device 31 includes, in addition to the mold holding mechanism 32 having the fixed platen 32a, the movable platen 32b, and the intermediate mold support frame 32c, an intermediate mold moving mechanism 61 for moving the intermediate mold support frame 32c relative to the fixed platen 32a, a mold clamping mechanism 33 for moving the movable platen 32b relative to the fixed platen 32a, and a mold parting mold opening/closing mechanism 62 for opening and closing a parting mold of the movable mold 103. The intermediate mold moving mechanism 61 and the split mold opening and closing mechanism 62 will be described later with reference to fig. 8 and 9.

The mold holding mechanism 32 includes a fixed platen 32a positioned between the injection device 21 and the mold device 101, a movable platen 32b positioned at a position spaced apart from the fixed platen 32a by the mold device 101 and movable toward and away from the fixed platen 32a, and an intermediate mold support frame 32c disposed between the fixed platen 32a and the movable platen 32b and movable toward and away from the fixed platen 32 a. The mold clamping unit 31 is provided with one or more tie bars 32d extending from the fixed platen 32a toward a rear platen 34 described later to connect the fixed platen 32a and the rear platen 34. In this example, the movable platen 32b and the intermediate mold support frame 32c are configured to guide the separation/approach displacement with respect to the fixed platen 32a by the tie bars 32d, but may not be guided by the tie bars 32 d.

In the mold holding mechanism 32, a fixed platen 32a is fixedly attached to the base frame 2. On the other hand, the movable platen 32b and the intermediate mold support frame 32c are respectively disposed on guides 32e laid on the base frame 2, and are slidable independently of each other in a direction to move away from and a direction to approach the fixed platen 32 a.

In addition, at the position where the movable platen 32b and the intermediate mold support frame 32c are separated from the fixed platen 32a, the movable mold 103 and the intermediate mold 104 of the mold apparatus 101 are in an open state in which they are opened from the fixed mold 102. When the movable platen 32b and the intermediate mold support frame 32c are brought close to the fixed platen 32a from the separated positions, the movable mold 103 and the intermediate mold 104 are brought into a mold closed state in which they are closed with respect to the fixed mold 102, and the movable platen 32b and the intermediate mold support frame 32c are brought close to the fixed platen 32a, respectively, whereby the movable mold 103 and the intermediate mold 104 are brought into a mold closed state in which they are pressed against the fixed mold 102. Here, a direction of approaching the fixed platen 32a of the fixed mold 102 to which the mold apparatus 101 is attached is set to the front side, and a direction of separating from the fixed platen 32a is set to the rear side. Most of the parts other than the fixed platen 32a of the mold clamping device 31 are forward in the right direction toward the fixed platen 32a and rearward in the left direction away from the fixed platen 32a in fig. 1.

For example, as shown in fig. 2, the illustrated intermediate mold support frame 32c has a frame shape such as a rectangular shape in plan view, and a rotation shaft 41 extending in a mold width direction (not a left-right direction in fig. 2) orthogonal to the front-rear direction in a plane parallel to a horizontal plane is provided rotatably. The rotary shaft 41 is also a mold support member because the intermediate mold 104 is attached thereto and supports the intermediate mold 104. In this example, the axial direction of the rotation shaft portion 41 is set to be parallel to the horizontal direction, but the axial direction of the rotation shaft portion is not limited thereto, and may be set to be parallel to the vertical direction, for example.

The intermediate mold support frame 32c is provided with an intermediate mold rotating mechanism that rotates the intermediate mold 104 while mainly rotating the drive shaft body 43 using the rotating shaft 41. Although not shown, the intermediate mold turning mechanism may be provided on the other end 42b side of the one end 42a and the other end 42b of the turning shaft 41, for example. As described above, this can be achieved by concentrating the heat medium flow paths P1, P2 for adjusting the temperature of the intermediate mold 104 on the side of the one end portion 42 a.

As shown in fig. 8 and 9, the intermediate mold moving mechanism 61 for moving the intermediate mold support frame 32c relative to the fixed platen 32a may be constituted by, for example, a hydraulic cylinder 61a and a piston rod 61b that are attached to the fixed platen 32a and the intermediate mold support frame 32c, respectively, and are operated by a hydraulic pump driven by a motor. In this example, two pairs of hydraulic cylinders and piston rods are provided outside the fixed mold 102 and the intermediate mold 104 in the mold width direction, but one pair or three or more pairs may be provided. Although not shown in the drawings, the intermediate mold moving mechanism can move the intermediate mold support frame relative to the movable platen by attaching a hydraulic cylinder or the like to the movable platen, not to the fixed platen.

As shown in fig. 1, the clamping mechanism 33 of the clamping device 31 includes a rear platen 34 disposed on the base frame 2, a clamping motor 35 provided on the rear platen 34, a motion conversion mechanism 36 that converts the rotational motion of the clamping motor 35 into a linear motion in the displacement direction of the movable platen 32b, and a toggle mechanism 37 that increases the force transmitted to the motion conversion mechanism 36 and transmits the force to the movable platen 32 b.

The motion conversion mechanism 36 can be any of various mechanisms capable of converting a rotational motion into a linear motion, but in this example, it includes a screw shaft 36a rotationally driven by the mold clamping motor 35 and a nut 36b screwed to the screw shaft 36 a. The motion conversion mechanism 36 may be a ball screw. A toggle mechanism 37 for increasing the transmission force from the motion conversion mechanism 36 is connected via joints to a nut 36b for connecting the motion conversion mechanism 36 and a plurality of links 37a to 37c for connecting the movable platen 32 b. The number and shape of the links and joints can be changed as appropriate, but as shown in fig. 1, a pair of links consisting of links 37a to 37c located above and below the crosshead 37d is swingably connected to a crosshead 37d connected to a nut 36b and extending in the vertical direction.

In addition, a mold thickness adjusting motor 38 may be provided in the rear platen 34 in addition to the mold clamping motor 35. The die thickness adjusting motor 38 is operated to adjust the gap between the fixed platen 32a and the rear platen 34 movably mounted on the base frame 2 by applying a rotational driving force to a screw shaft and a nut connected to an extension of each tie bar 32d of the die holding mechanism 32. Thus, when the mold apparatus 101 is replaced, the thickness of the mold apparatus 101 due to a temperature change is changed, or the like, the mold thickness can be adjusted so that a desired mold clamping force can be applied to the mold apparatus 101. Although not shown, the fixed platen side is movable on the base frame 2, and thus the die thickness can be reliably adjusted even if the rear platen side is fixed.

As shown in fig. 8 and 9, the mold clamping device 31 includes a split mold opening and closing mechanism 62, and the split mold opening and closing mechanism 62 includes a piston rod 62a, a hydraulic cylinder 62b, and the like, and thereby moves the split mold of the movable mold 103 forward and backward in the mold width direction to open and close the mold.

The mold clamping device 31 shown in the figure is a horizontal type in which the moving direction of the movable platen 32b is parallel to the horizontal direction, but may be a vertical type in which the moving direction is vertical.

(injection device)

The injection device 21 mainly includes a cylinder 22 such as a cylinder extending toward the mold device 101, a screw 23 disposed inside the cylinder 22 so that a central axis is parallel thereto and a screw is spirally threaded therearound, a heater 24 such as a belt disposed on an outer peripheral side of the cylinder 22 so as to surround the periphery thereof, and a motor case 25 disposed on a rear side of the cylinder 22 and the screw 23. Although not shown, a metering motor for rotating the screw 23 about the center axis by accumulating a predetermined amount of molding material at the distal end portion of the cylinder 22, an injection motor for performing forward and backward displacements of the screw 23 in respective directions of a direction approaching the mold apparatus 101 and a direction separating from the mold apparatus 101, a pressure detection sensor for detecting a pressure received by the screw 23 from the molding material, and the like are disposed in the motor case 25.

Here, a direction in which the fixed platen 32a of the mold clamping device 31 attached to the fixed mold 102 of the mold device 101 approaches is referred to as a front side, and a direction away from the fixed platen 32a is referred to as a rear side. Therefore, when the injection device 21 is viewed on the right side of the fixed platen 32a in fig. 1, the left direction toward the fixed platen 32a is the forward side, and the right direction away from the fixed platen 32a is the rearward side.

The cylinder 22 is provided with a supply port 22a to which a hopper for feeding the molding material into the cylinder 22 can be attached on the rear side of the motor case 25. A nozzle 22b having a smaller cross-sectional area is provided at the front end of the cylinder 22 close to the die apparatus 101. A water-cooled cylinder 22c by water cooling or the like can be provided near the supply port 22 a.

As shown in the drawing, the heater 24 disposed around the cylinder block 22 including the nozzle 22b is divided into a plurality of portions in the cylinder axial direction, for example, and the inside of the cylinder block 22 inside each heater portion can be heated at different temperatures. A temperature detector can be provided at each heater portion.

The front end side of the screw 23 is provided with a check ring, not shown, which is displaced forward and backward together with the screw 23 to prevent a backward flow of the molding material conveyed to the rear side from the front side, around a narrow waist portion provided by partially reducing the outer diameter thereof. The check ring is displaced forward and backward relative to the screw 23 in accordance with, for example, a pressure received from the molding material located on the front side or the rear side thereof, thereby permitting only a flow of the molding material from the rear side to the front side.

According to the injection device 21 having such a configuration, the molding material charged into the cylinder 22 from the supply port 22a is gradually melted by the rotation of the screw 23 driven by the metering motor under the heating of the heater 24 on the outer peripheral side of the cylinder 22, and is conveyed forward inside the cylinder 22 and accumulated at the front end portion of the cylinder 22. At this time, the screw 23 is moved backward by the injection motor, and a space for accumulating the molding material is formed at the tip end of the cylinder 22.

Then, by moving the screw 23 forward and forward, the molding material at the tip end of the cylinder 22 is injected into the mold apparatus 101 through the nozzle 22 b. Thereafter, pressure holding is performed in which the molding material filled in the cavity of the mold apparatus 101 is pressurized by the molding material remaining at the distal end portion of the cylinder 22. In this case, the insufficient molding material due to the cooling shrinkage of the molding material in the injection cavity of the mold apparatus 101 can be compensated.

The injection molding machine 1 is of a coaxial screw type, and may be a screw preplasticizing type injection molding machine which is structurally and functionally separate from the plasticizing cylinder and the plasticizing screw, and the injection cylinder and the injection plunger.

(moving device)

The moving device 26 is, for example, a forward/backward driving mechanism provided at a lower portion of the motor case 25 of the injection device 21 and configured to move the injection device 21 forward and backward with respect to the fixed platen 32 a.

Various mechanisms can be used as the forward/backward driving mechanism constituting the traveling device 26, but the illustrated traveling device 26 includes a hydraulic pump 27 such as a hydraulic pressure, a pump operation motor 28 by an electric motor or the like for operating the hydraulic pump 27, and a double-acting hydraulic cylinder 29 for supplying a hydraulic fluid from the hydraulic pump 27 and performing a pushing/pulling motion of a piston rod whose tip end is fixed to the fixed platen 32 a.

The traveling device 26 further includes a slide base 26a on which the hydraulic pump 27, the pump motor 28, and the hydraulic cylinder 29 are mounted, and a guide 26b that guides the linear motion of the slide base 26a laid on the base frame 2. This realizes the forward and backward displacement of the injection device 21 placed on the upper part of the slide base 26 a.

The moving device 26 can separate the injection device 21 from the mold device 101, or bring the injection device 21 close to the mold device 101 to press the nozzle 22b of the cylinder 22 of the injection device 21 against the so-called nozzle contact of the mold device 101 at a predetermined pressure.

(mold apparatus)

The mold apparatus 101 attached to the injection molding machine 1 includes a stationary mold 102, a movable mold 103, and an intermediate mold 104. In a clamped state by the clamping device 31, the mold device 101 divides an injection molding cavity between the fixed mold 102 and the intermediate mold 104, and divides a blow molding cavity between the movable mold 103 and the intermediate mold 104.

More specifically, as shown in fig. 8 (b), the fixed mold 102 is provided with a fixed-side cavity portion 102 a. In the clamped state, the punch 104a of the intermediate mold 104 is inserted into the fixed-side cavity 102a, and the injection molding cavity corresponding to the shape of the preform PF is partitioned between the fixed-side cavity 102a and the punch 104 a.

The movable mold 103 has split molds 103b that are separable in the mold width direction, and a movable-side cavity portion 103a that is partitioned by combining the split molds 103b is provided (see fig. 8 (b) and 9 (b)). In the clamped state, a blow molding cavity corresponding to the shape of the molded article MP is partitioned between the movable-side cavity 103a and the punch 104a of the intermediate mold 104 inserted and disposed in the movable-side cavity 103 a. In the split mold 103b of the movable mold 103, portions moved in the same direction in the mold width direction by the split mold opening and closing mechanism 62 can be connected to each other by the split

mold connecting members

63a, 63 b.

The intermediate mold 104 has a boss portion 104a on each surface facing the fixed mold 102 or the movable mold 103 of each of two core molds existing in the front-rear direction with the rotating shaft portion 41 interposed therebetween.

In the illustrated example, two fixed-side cavity portions 102a of the fixed mold 102, two male mold portions 104a of the middle mold 104, and two movable-side cavity portions 103a of the movable mold 103 are arranged in the mold width direction, and six in total twelve are arranged in the height direction (the vertical direction in fig. 8a and 9 a), but the number thereof can be appropriately changed.

The mold apparatus 101 is attached to the injection molding machine 1 as appropriate in accordance with the shape of a molded product to be manufactured, and is replaceable, and is not regarded as a part of the injection molding machine 1.

(operation of injection Molding machine)

The injection molding machine 1 described above operates to perform the respective steps as described below.

In the mold opening state of the mold apparatus 101 shown in fig. 8, a mold closing step is performed in which the movable platen 32b is moved to the fixed platen 32a side by the mold clamping mechanism 33, and the intermediate mold support frame 32c is moved to the fixed platen 32a side by the intermediate mold moving mechanism 61.

Next, in a state where a predetermined amount of the molding material is accumulated and disposed in the injection device 21 in the later-described metering at the time of the above-described molding, as shown in fig. 9, a mold clamping process of bringing the mold device 101 into a mold clamped state is performed using the mold clamping device 31. In the mold clamping step, an injection molding cavity is partitioned between the fixed mold 102 and the intermediate mold 104, and a blow molding cavity is partitioned between the movable mold 103 and the intermediate mold 104.

Then, an injection step of injecting the molding material into the injection molding cavity of the mold apparatus 101 by advancing the screw 23 and filling the injection molding cavity with the molding material is performed. In the injection step, after the injection molding cavity is filled with the molding material, the screw 23 is further advanced to maintain the molding material present inside the distal end portion of the injection device 21 at a predetermined pressure. Then, the molding material filled in the cavity for injection molding is cooled and solidified. Thereby, the preform PF is molded in the injection molding cavity. At this time, the molding material separately charged into the injection device 21 is melted while being conveyed to the tip end portion of the injection device 21 by the rotation of the screw 23 under the heating of the heater 24, and a predetermined amount of the molding material is disposed at the tip end portion.

In parallel with the injection step, the blow molding step is performed in the blow molding cavity. The preform PF molded in the injection molding cavity before the inversion of the intermediate mold 104 is arranged in the blow molding cavity. In the blow molding step, a fluid such as air or other gas is supplied to the preform PF, and the preform PF is expanded in the blow molding cavity to mold the molded article MP.

Then, the mold clamping mechanism 33 and the intermediate mold moving mechanism 61 of the mold clamping device 31 are operated to move the movable platen 32b and the intermediate mold support frame 32c to the sides separated from the fixed platen 32a, respectively, to perform a mold opening step of opening the mold device 101.

After the mold opening step, a mold split opening and closing step is performed in which the mold split of the movable mold 103 is opened by the mold split opening and closing mechanism 62 to take out the molded article MP, and then the mold split of the movable mold 103 is closed.

Here, an intermediate mold rotating step of reversing the intermediate mold 104 by the intermediate mold rotating mechanism is performed. Thus, the punch part 104a of the core mold of the intermediate mold 104 on the side from which the molded article MP is collected in the split mold opening and closing step faces the fixed-side cavity part 102a of the fixed mold 102. On the other hand, the punch portion 104a of the core mold of the intermediate mold 104 on the side where the preform PF is molded in the injection process faces the movable-side die portion 103a of the movable mold 103 while holding the preform PF.

The intermediate mold rotating step may be performed substantially at the same time as the split mold opening and closing step or before or after the split mold opening and closing step.

In injection molding using the injection molding machine 1, the mold closing step, the injection step, the blow molding step, the mold opening step, the parting mold opening and closing step, and the intermediate mold rotating step are repeated as described above.

Claims

1. An injection molding machine for molding by injecting a molding material into a mold,

the injection molding machine is provided with a mold supporting member for supporting the mold,

the mold supporting member has one or more heat medium flow paths communicating with the mold-side flow path and through which a heat medium for adjusting the temperature of the mold flows,

the inlet and the outlet of the at least one heat medium channel are present on one of both sides of the mold supporting member across the mold.

2. The injection molding machine according to claim 1,

the heat medium flow path includes:

an inflow side flow path section that guides the heat medium to the mold side flow path by flowing the heat medium from the inflow port on the one side; and

and an outlet-side flow path portion that guides the heat medium to the outlet while flowing from the mold-side flow path on the one side.

3. The injection molding machine according to claim 2,

the mold supporting member is a rotary shaft portion extending in an axial direction parallel to the mold width direction and rotating the mold, the rotary shaft portion having a shaft body portion extending between both end portions,

the inflow side flow path portion and the outflow side flow path portion each have an annular portion provided around the shaft main body portion at positions different from each other in the axial direction of the one side.

4. The injection molding machine according to claim 3,

a plurality of the heat medium flow paths are provided,

an inlet and an outlet of each of the plurality of heat medium channels are present on one of both sides of the mold supporting member across the mold,

the annular portions of the inflow side channel section and the outflow side channel section in each heat medium channel are arranged in the axial direction on the one side.

5. The injection molding machine according to claim 3 or 4,

among the plurality of annular portions, an annular portion located on an axially outer side has a longer circumferential length than an annular portion located on an axially inner side.

6. The injection molding machine according to any one of claims 3 to 5,

the one-side portion of the rotation shaft portion has:

an inner flow passage partition member provided in the shaft main body; and

and an outer flow path dividing member which is disposed so as to surround the inner flow path dividing member and divides the annular portion between the inner flow path dividing member and the outer flow path dividing member.

7. The injection molding machine according to claim 6,

the rotary shaft portion has a displacement regulating member that is connected to an axially outer end surface of the inner flow passage partition member to regulate an axial displacement amount of the shaft body portion.

8. The injection molding machine according to claim 7,

the connection portion between the inner flow passage defining member and the displacement restricting member includes an elastic member that resists the action of an axial force in a direction in which the displacement restricting member is axially separated from the inner flow passage defining member.