JPH0796152B2 - Multi shot molding machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement of a molding machine, such as a die casting machine, which performs injection molding by filling a material into a cavity.

[Prior Art] In this type of molding machine, a material is injected from an injection device into a cavity of a mold, filled, and molded. A conventional molding machine usually has one injection section for each mold.

[Problems to be Solved by the Invention] However, such a mechanism causes a large difference in molding conditions because the injection port is fixed regardless of the product shape. That is, depending on the product shape, there are optimum molding condition values such as the optimum speed when the material is filled, but it is virtually impossible to control different molding conditions with a single injection part. Further, when a material is supplied to a product part far away from the injection part for molding, a single large-capacity injection system has drawbacks in terms of, for example, the heat retaining property of the material and the obtained molding pressure. There is.

[Means for Solving the Problems] The present invention has been made in order to overcome the above-mentioned drawbacks of the prior art, and is directed to a plurality of casting passages in a mold in parallel with each other in the same casting direction. The separate casting sleeves are integrally connected to each other, and the plunger tips are slidably provided in the respective casting sleeves.

[Operation] According to the present invention configured as described above, the molding condition can be optimized by supplying the material from each injection part to each part of the mold according to the shape of the mold and the molding condition requirement.

Further, since the path to the injection section and the product section which the injection section is responsible for can be minimized, it is extremely advantageous for keeping the temperature of the material, propagating the molding pressure, and mixing the air in the mold during injection into the material.

In addition, it is possible to solve the problems of the structure of the large-capacity injection mechanism in the case of a single large-capacity injection system, the large molding force generator, and the like.

According to the present invention, since the casting sleeves are integrally connected to each other in parallel to the same casting direction, the space occupied by the casting sleeves is reduced.

Embodiments Embodiments will be described below with reference to the drawings.

FIG. 1 and FIG. 2 are diagrams showing a vertical type vertical casting die casting machine, and FIG. 1 is a partial cross-sectional view (I- of FIG. 2).
2 is a sectional view taken along line II-II in FIG.

In the vertical casting device portion indicated by reference numeral 1, an injection cylinder support plate 3 is horizontally arranged below the pit 2, and the injection cylinder support plate 3 includes four tie rods 4 in a vertical state. Is fixed at its lower end, and the upper end of each tie rod 4 is fixed to a fixed plate 6 fixed to a base 5 via a connecting member 7. The injection cylinder support plate 3 is
In the pit 2, it can be supported from below.

In the space formed by these tie rods 4, one injection cylinder 8 facing upward is rotatably supported by the injection cylinder support plate 3 through a horizontal shaft 9 at its lower end. It is arranged.

Two pistons 10a and 10b are slidably provided in one injection cylinder 8 having two parallel piston chambers 8a and 8b, respectively.

The upper ends of the piston rods 11a and 11b, which are integral with the pistons 10a and 10b of the injection cylinder 8, are connected to the plungers 13a and 13b via couplings 12a and 12b, respectively, and are connected to the upper ends of the plungers 13a and 13b. Plunger chips 14a and 14b are fixed to each of them.

On the other hand, the reference numeral 15 is a block, which is formed in a hollow shape. A horizontal engaging portion 16 is formed inside the lower end of the block 15, and the upper surface of the engaging portion 16 is
The respective piston rods 11a and 11b and the plunger 13
The lower surfaces of the couplings 12a and 12b, which are the connecting portions of a and 13b, are engaged with the lower surface outer peripheral portions of the convex portions 17a and 17b formed by using a collar or the like. Then, when the block 15 rises, the engaging portions 16 hold the convex portions 17a, 17b, the convex portions 17a, 17b also rise together, and the plunger tips 14a, 14b and the casting sleeves 18a, 18b are always kept. The same positional relationship is maintained in the vertical direction so that they can surely rise at the same time. This is because when the casting sleeves 18a, 18b containing the molten metal are raised, the plunger tips 14a, 14b are pulled out downward so that the molten metal does not come out of the casting sleeves 18a, 18b. Of course, the couplings 12a and 12b may be used as the protrusions 17a and 17b.

Two casting sleeves 18a and 18b are attached to the upper end of the block 15 in a vertical state and in a state of being parallel to each other.
Plunger tips 14a and 14b are slidably fitted therein.

On the other hand, for example, four cylinders 15a are formed in the block 15 in the vertical direction, and the tips of, for example, four rams 19 fixed to the rod end side of the injection cylinder 8 have the cylinders 15a.
Each of them is slidably fitted therein, and is configured to be able to raise the block 15 by supplying hydraulic oil from a hydraulic power source (not shown) into the cylinder 15a through the ram 19.

On the other hand, in two positions of the fixed platen 6, there are fixed sleeves in a vertical state.
6a and 6b are attached, and the casting sleeve 18 described above
When a and 18b are raised, they can be engaged with the fixed sleeves 6a and 6b, respectively.

Reference numeral 20 is a fixed mold attached to the fixed plate 6, and a movable mold 31 arranged so as to be pressed against the fixed mold 20 from above constitutes a mold 32.

The movable mold 31 is attached to the movable plate 33. The movable plate
The 33 is vertically movably supported by four columns 34 which are erected from the fixed plate 6 and are mounted between the upper plate and the cylinder platen 35. The cylinder platen 35 has a mold clamping cylinder 35.
It is moved up and down by the operation of a and the mold opening cylinder 36. Reference numeral 37 is a ram of the mold clamping cylinder 35a, and 38 is a power unit and a tank for operating the mold clamping cylinder 35a and the mold opening cylinder 36.

In this embodiment, the casting parts 18a, 18b and the plunger tips 14a, 14b constitute the injection part. In this embodiment, however, two injection parts are provided, and independent drive control is possible. The two plunger rods 11a and 11b are configured to vertically move the plunger tips 14a and 14b independently of each other.

Between the protrusions 17a, 17b at the tip of the piston rods 11a, 11b and the couplings 12a, 12b, an L-shaped arm extending horizontally is formed.
25a and 25b are fixed, and magnetic scales 26a and 26b are attached to the vertical portions of the arms 25a and 25b, respectively. On the other hand, the magnetic head 27a,
27b are respectively fixed, and the position of the position detecting device composed of the magnetic heads 27a, 27b and the magnetic scales 26a, 26b can detect the injection stroke position of the piston rods 11a, 11b and the plunger tips 14a, 14b. .

28 is a hydraulic pump, 29 is an electromagnetic switching valve, 30a and 30b are electromagnetic proportional flow control valves or flow control valves that can control the valve opening by pulse signals, and the A port of the solenoid switching valve 29 is a separate flow control valve. The chambers 8e and 8f on the head end side of the injection cylinder 8 are connected via valves 30a and 30b, respectively.
The injection speed of each injection cylinder 8 can be controlled independently. The B port of the electromagnetic switching valve 29 is connected to the rod end chambers 8c and 8d of the injection cylinder 8.

39a and 39b are setting devices that can set the injection speed according to the injection stroke, and 40a and 40b are comparators.In the comparators 40a and 40b, the signals from the setting devices 39a and 39b and the positions of the magnetic heads 27a and 27b, etc. The signals from the detectors are compared, and the flow rate control valves 30a, 30 are set so that a predetermined injection speed can be obtained at a predetermined injection stroke position.
It can send a signal to b.

Reference numeral 22 denotes a tilting device attached to a part of the two tie rods 4 via brackets 22a. By rotating the drive link 23, the driven link 24 is moved in the left-right direction in FIG. It is possible to move the injection cylinder 8 about a shaft 9 as a swing center between a vertical position shown by a solid line in FIG. 2 and an inclined position shown by a dotted line.

Next, the operation of this embodiment configured as described above will be described.

In order to supply the molten metal to the casting sleeves 18a, 18b from the state shown by the solid line in FIG. 2, first, the working oil is supplied to the rod end side chambers 8c, 8d of the injection cylinder 8 and the ram 19 is supplied.
Open the hydraulic oil discharge port from the cylinder 15a at the lower end of the. Alternatively, instead of simply opening the hydraulic oil discharge port of the cylinder 15a, the counter balance pressure or a pressure slightly higher than the counter balance pressure is held in the cylinder 15a. Then, as the piston rods 11a and 11b descend, the convex portions 17a and 1b
The block 15 descends together via 7b and becomes integral with the plunger tips 14a, 14b at the same time as the block 15, and thus
The casting sleeves 18a, 18b descend. Therefore, the plunger chips 14a, 14b and the casting sleeves 18a, 18b are separated from the docking state with respect to the fixed mold 20 without changing their relative positional relationship, and are located below the fixed mold 20. When the tilting device 22 is operated in this state, the drive link 23 rotates the driven link 24, so that the injection cylinder 8, the plunger tips 14a and 14b, and the casting sleeves 18a and 18b are all shown by a chain line in FIG. The casting sleeves 18a and 18b are supplied with the molten metal from the molten metal supply device including the ladle 29 and the like in the tilting limit. After the supply of the molten metal is completed, the injection cylinder 8, and therefore the casting sleeves 18a, 18b and the plunger tips 14a, 14b are returned to the vertical state before the rotation.
After that, the chamber 8c on the rod end side of the injection cylinder 8
The hydraulic pressure in the chamber 8e and the chambers 8e and 8f on the head end side is released, and the hydraulic pressure is supplied to the cylinder 15a through the ram 19. Therefore, the block 15 rises and the casting sleeves 18a and 18b also rise, and at the same time, the convex portion 17 is inserted through the engaging portion 16 of the block 15.
a, 17b are lifted and the plungers 13a, 13b and thus
Plunger tips 14a, 14b move up, casting sleeve 18
a, 18b and the plunger tips 14a, 14b ascend without changing the relative positional relationship, and the casting sleeves 18a, 18b and the fixed sleeves 6a, 6b of the fixed platen 6 are engaged with each other in a spigot state. Become one. As a result, the molten metal can be moved to a ready-to-inject state without changing the surface of the molten metal, and inconveniences such as spilling and cooling of the molten metal are eliminated. This state is shown by a solid line in FIGS.

On the other hand, during the operation of the pouring device unit 1 as described above, the mold clamping cylinder 35a is operated to lower the movable platen 33 and the movable mold 31,
Finish the mold clamping.

After the engagement of the casting sleeves 18a, 18b and the fixed sleeves 6a, 6b in the spigot state is completed, hydraulic oil is supplied into the chambers 8e, 8f on the head end side of the injection cylinder 8 to move the piston rods 11a, 11b. The molten metal in the casting sleeves 18a, 18b is supplied to the mold space from two locations via the plunger tips 14a, 14b, and the injection is completed.

The cavity 32 and the injection position of the mold 32 shown in FIG. 1 may be slightly different depending on the cast product 41 obtained by injection. For example, one is a thick portion 41a and the other is a model as shown in FIG. There is also a cast product 41 which consists of a thin portion 41b.

In such a case, if the casting conditions from the casting ports 42a, 42b shown as the left and right biscuits are the same, the molten metal flow conditions from the left and right are significantly different, and a good casting product 41
Can't get Generally, it is necessary to increase the flow rate of the molten metal in the thin portion 41b, and therefore, it is necessary to set the injection speed higher than that at the time of the injection of the thick portion 41a. Further, in the case of the thin portion 41b, it is also necessary to make the injection pressure a little smaller and make the temperature of the injected molten metal a little higher.

Recently, the cast product 41 tends to be large and complicated, and the cast product 41 having a more complicated shape than the cast product 41 shown in FIG. 3 has two or more casting ports. Part 42a,
It is necessary to control so that the injection conditions from 42b are changed according to the injection stroke or the like.

In such a case, since it is necessary to control the injection speed separately according to the forward movement positions of the piston rods 11a, 11b and the plunger tips 14a, 14b of the left and right injection cylinders 8 in FIG. The injection conditions such as the injection speed change position are set by the respective setters 39a and 39b.

Then, the signals emitted from the position detectors such as the magnetic heads 27a and 27b in response to the forward movement of the piston rods 11a and 11b and the setting signals from the setters 39a and 39b are supplied to the respective comparators 40.
The control signals are sent to the flow rate control valves 30a and 30b after being compared at a and 40b. As a result, the injection speed changes according to the set speed as the piston rods 11a and 11b move forward, and the left and right injection conditions are individually controlled. Therefore, if the injection conditions from multiple injection parts are set appropriately, good quality can be achieved in terms of molten metal flow, product compactness, prevention of cavities due to gas entrainment, and product casting. The cast product 41 can be easily obtained.

In this way, by injecting the molten metal into the mold 32 from a plurality of injection portions, a great degree of freedom can be obtained in the runner's way plan and the like determined from the product shape, and it becomes possible to satisfy the optimum forming conditions.

When the injection is completed and the cast product cools, clamp the mold,
The casting tip is taken out of the movable mold 31 and the pistons 10a and 10b of the injection cylinder 8 are operated to move the plunger tip.
One cycle is completed by lowering 14a and 14b to the positions shown in FIG.

In the above embodiment, the number of injection parts is two, but it may be three or more. Further, although the tilting device 22 is shared in the above embodiment, it may be separately provided. Furthermore, one injection cylinder 8 may be two parallel injection cylinders.

Further, in the above embodiment, the injection sleeves 18a and 18b are engaged with the lower surfaces of the fixed sleeves 6a and 6b attached to the fixed platen 6, but the injection sleeves 18a and 18b are not provided with the fixed sleeves 6a and 6b. The upper end surfaces of the sleeves 18a and 18b may be directly engaged with the lower side of the casting path of the fixed mold 20.

In the above embodiment, the ram 19 parallel to the piston rods 11a and 11b of the injection cylinder 8 is fixed to the upper part of the injection cylinder 8, and the cylinder 15a is provided to the block 15 which is integrally provided below the casting sleeves 18a and 18b. , The block 15 is provided slidably with respect to the ram 19, but instead of the ram 19 and the cylinder 15a, a state in which the block 15 is parallel to the piston rods 11a and 11b of the injection cylinder 8 between the injection cylinder 8 and the block 15. Then, it is also possible to provide a block lifting device composed of a normal cylinder for lifting the block 15.

In the above embodiment, the piston rods 11a and 11b
Protrusions 17a, 17b are provided on the block 15, and an engaging portion 16 capable of holding the protrusions 17a, 17b is provided on a part of the lower portion of the block 15 to block 15.
The piston rods 11a, 11b and the plungers 13a, 13b can be raised at the same time by the action of the engaging portion 16 and the convex portions 17a, 17b, but it is clear that other connecting structures may be used. is there.

In addition, in the above-mentioned embodiment, the two injection parts can be operated independently of each other, but a plurality of injection parts may be operated collectively by a common drive device. That is, the plungers are provided upright at the ends of the members branched from the tip of the piston rod of one injection cylinder to the left and right, and two plunger chips are simultaneously moved up and down by one piston. Thus, the material path in the mold may be made relatively simple to improve the injection state.

Further, in the above embodiment, as each control of a plurality of injection conditions, an example in which the injection speed is controlled according to the forward movement position of the piston rods 11a, 11b has been shown. It is possible to control by the advance position of 11a, 11b, or by a timer, or both the injection speed and the injection pressure can be controlled simultaneously.

The present invention can also be used in a horizontal casting machine.

[Effects of the Invention] As described above, according to the present invention, a plurality of injection parts are provided and a plurality of injection sleeves and plunger chips are provided. Therefore, the injection target is injected into the mold from a plurality of locations at the same time or with a slight timing shift. It is possible to inject objects, change the pressurizing timing, and individually control the injection conditions and injection conditions from multiple locations, satisfying the requirements of each part of the product regardless of the product shape. It is possible to perform high-quality molding.

Further, the path to the injection section and the product section which the injection section is responsible for can be minimized, so that the material can be kept warm and the molding pressure can be evenly propagated. Further, mixing of air in the mold during injection into the material is prevented.

Further, when a plurality of injection units are operated by separate driving devices, a large capacity injection mechanism and a large molding force generator in the case of a single large capacity injection system are not required, and the configuration can be simplified.

In the present invention, the space occupied by the casting sleeve is small,
The molding machine as a whole will be small and compact.

[Brief description of drawings]

1 and 2 are longitudinal sectional views showing one embodiment of the present invention. FIG. 1 is a sectional view taken along the line II of FIG. 2, and FIG.
It is the II-II sectional view taken on the line of FIG. FIG. 3 is a perspective view showing an example of a cast product. DESCRIPTION OF SYMBOLS 1 ... Vertical casting device part, 3 ... Injection cylinder support plate, 6 ... Fixed board, 8 ... Injection cylinder, 10a, 10b ... Piston, 11a, 1
1b ... Piston rod, 13a, 13b ... Plunger, 14a, 14b
… Plunger tip, 15… Block, 15a… Cylinder, 1
8a, 18b ... casting sleeve, 19 ... ram, 20 ... fixed mold, 22
… Tilt device, 31… Movable mold, 32… Mold, 35… Movable plate.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Minor Yoshida 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor Takahiro Ide 3-3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation (56) Bibliography SHO 64-54953 (JP, U)

Claims (1)

[Claims] 1. A plurality of casting passages into a mold are provided with separate casting sleeves which are oriented parallel to each other in the same casting direction and are integrally connected to each other. A multi-shot type molding machine characterized in that a plunger tip is provided slidably.