JP3211748B2 - Temperature control device and temperature control method for vertical rotary injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling the temperature of a rotary table and a mold of a vertical rotary injection molding machine and a temperature control method.

[0002]

2. Description of the Related Art As a device for controlling a mold temperature of a vertical rotary injection molding machine, a flow hole is formed in a rotary table which is intermittently rotated at a predetermined angle around a central axis by a rotary drive device. At the same time, a swivel joint is provided on the central axis, and temperature control water (cooling water) is supplied to the mold on the rotary table through the flow path of the swivel joint and the circulation hole of the rotary table to control the temperature of the mold. One is known (Japanese Utility Model Publication No. 7-1948).

[0003]

In the above apparatus, the rotary table is heated when the water whose temperature has been raised by cooling the mold is discharged through the circulation holes of the rotary table. I do. For this reason, the positioning holes formed in the rotary table are shifted radially outward with the thermal expansion of the rotary table, and it becomes difficult to insert the positioning pins normally. Further, when the rotary drive of the rotary table has a configuration in which a gear is formed on the outer periphery of the rotary table and the pinion of the drive motor is meshed with the gear, the necessary backlash between the gear and the pinion causes the rotary table to rotate. However, there is a problem that the driving torque and the noise are increased because the thermal torque is eliminated due to the thermal expansion.

An object of the present invention is to provide a temperature control device and a temperature control method for a vertical rotary injection molding machine that can prevent thermal expansion of a rotary table.
Another object of the present invention is to provide a temperature control device and a temperature control method for a vertical rotary injection molding machine capable of controlling the temperature of a mold with high accuracy.

[0005]

In order to achieve at least one of the above objects, the present invention provides a rotary table which is intermittently rotated at a predetermined angle about a central axis by a rotary driving device. In a vertical rotary injection molding machine on which a mold is mounted, a ring-shaped piping manifold having a plurality of communication holes is fixed on the rotary table concentrically with the center axis, and a flow hole is formed. A swivel joint having a plurality of table channels that can communicate with the communication holes of the rotary table and a plurality of mold channels that can communicate with the communication holes of the piping manifold, And the communication holes of the pipe manifold and the mold are connected to each other by pipes outside the rotary table.

In the above means, the temperature of the mold is controlled by circulating a temperature-adjusted liquid such as water or oil from the mold flow passage of the swivel joint to the mold through the communication hole of the piping manifold and the piping. The temperature of the rotary table is controlled by circulating a temperature-adjusted liquid such as water or oil from the table channel of the swivel joint to the circulation hole of the rotary table. Since the piping is arranged outside the rotary table, the temperature of the rotary table does not rise due to the temperature control liquid in the mold.

In the temperature control device of the vertical rotary injection molding machine, it is preferable that the flow hole is formed near the positioning hole provided on the rotary table so as to surround the positioning hole. In this configuration, since the temperature is mainly controlled around the positioning hole of the rotary table, thermal displacement of the positioning hole is effectively prevented,
Further, thermal expansion of the positioning pin inserted into the positioning hole is also prevented.

The communication hole may be constituted by a supply hole, a return hole, and a communication hole of an accessory member which is detachably attached to the upper or lower surface of the rotary table.
In such a case, it is possible to remove the attached member from the rotary table as needed, and to perform maintenance and inspection of the communication hole and the like. The attachment member can be disposed between the positioning hole and the outer periphery of the rotary table.

According to a fifth aspect of the present invention, there is provided a temperature control apparatus for a vertical rotary injection molding machine having the above-mentioned structure, wherein the rotary table is provided through a swivel joint table channel and a mold channel. The temperature control liquid was caused to flow through the circulation hole and the mold.

In the above means, it is preferable to flow the temperature-adjusted liquid of the rotary table at a lower temperature than the temperature-adjusted liquid of the mold. Further, the temperature control liquid of the mold and the temperature control liquid of the rotary table can be of the same type.

[0011]

Embodiments of the present invention will be described with reference to the drawings. The accompanying drawings show an embodiment of the present invention. In the figure, reference numeral 1 denotes a rotary table. The rotary table 1 is provided with four sets of dies 2a, 2b, 2c, and 2d (hereinafter, suffixes a, b, c, and d are omitted as long as they are not confusing) at 90-degree intervals. With the annular sliding surface 1f (the members constituting the sliding surface 1f are not shown in FIG. 1) in contact with the guide plate 4, it is supported on the fixed platen 3 so as to be horizontally rotatable about a center shaft 5 also serving as a tie bar. Have been. Above the rotary table 1, a movable platen 7 is supported by three tie bars 5, 8, 8 so as to be movable up and down. 2 is clamped between the fixed plate 3 and the fixed plate 3. The mold clamping cylinder 9 and the movable platen 7 constitute a mold clamping device.

The rotary table 1 has a gear 1a, four positioning holes 1b, and four flow holes 1c. Gear 1
a is formed on the outer peripheral surface of the rotary table 1. Also, the four positioning holes 1b are set to have a phase of 45 with respect to the mold 2.
It is formed by a bush 11 with a flange (FIG. 7) fitted to the rotary table 1 at a staggered angle, and its upper part is covered by a lid 13 attached to the upper surface of the rotary table 1 with screws 12. The lid 13 is omitted in FIG.

The flow hole 1c is composed of a supply hole 1c1 (FIGS. 1, 4, and 5), a return hole 1c2, and a communication hole 1c3 (FIG. 5) interconnecting the supply holes 1c1 (FIGS. 1, 4 and 5). It is provided on the table 1. A supply hole 1c1 and a return hole 1c2 which constitute each flow hole 1c are bored substantially in the radial direction of the rotary table 1 in parallel with each other and vertically displaced from each other. It is closed in 3). The communication hole 1c3 is formed in an accessory member 1d which is detachably attached to the upper surface of the rotary table 1 in a liquid-tight manner with a bolt 16 between the positioning hole 1b and the outer periphery of the rotary table 1.
The accessory member 1d can be attached to the lower surface of the rotary table 1.

The fixed platen 3 has a drive motor 18 composed of an electric motor such as a servomotor or a hydraulic motor, a positioning cylinder 19 (FIGS. 1 and 7), and a plurality (4 in FIG. 3).
) Table guides 20 are provided. The drive motor 18 intermittently rotates the rotary table 1 at a predetermined angle (in the figure, 90 degrees), and engages the pinion 21 with the gear 1 a of the rotary table 1 to fix the fixed platen 3.
Is attached to the main body by bolts 22 (FIG. 6). The drive motor 18, the pinion 21, and the gear 1a constitute a rotary drive.

The positioning cylinder 19 is provided with a tip 2
A positioning pin 23 having a tapered shape 3a is inserted into a positioning hole 1b of the rotary table 1 to position the rotary table 1 at a predetermined position.
Is attached to the vehicle with bolts 24. Positioning pin 23
Is fixed to the piston rod 19a of the positioning cylinder 19. Each table guide 20 rotatably holds the outer peripheral portion of the rotary table 1 and is fixed to the fixed platen 3 with bolts 25 (FIG. 8).

Reference numeral 28 denotes a cylindrical swivel joint. The swivel joint 28 has four annular grooves 28
a, 28b, 28c, 28d and a pair of mold channels 28
e, 28f and a pair of table flow paths 28g, 28h, which are fitted concentrically on the center shaft 5, fitted respectively into the fixed holes 3a, 1e of the rotary table 1 and the lower part of the rotary table 1. The flange 28 i is provided to be fixed to the fixed platen 3 with a plurality of bolts 29. In addition, a pair of mold channels 28e and 28f and a pair of table channels 28g and 28
h may be provided at a position shifted in the circumferential direction as shown in FIGS. 3 and 4, or may be provided at a position shifted in the radial direction as shown in FIG.

Each annular groove 28a, 28b, 28c, 28d
Are formed horizontally on the outer peripheral surface of the swivel joint 28 with their positions shifted up and down, and a pair of mold channels 28e and 28f have upper portions opened in the respective annular grooves 28a and 28b and lower portions have a swivel portion. Joint 2
8 are formed so as to open at the lower end surfaces thereof, and a pair of table flow paths 28g and 28h
The swivel joint 28 is formed so as to have openings at the lower end surfaces of the swivel joints 28, respectively.

Reference numeral 31 denotes an annular pipe manifold. The piping manifold 31 includes a pair of communication holes 31a,
31b, the communication holes 31a, 31b are respectively connected to the respective annular grooves 28a, 28b of the swivel joint 28, and are fitted concentrically to the swivel joint 28, and a plurality of bolts are provided on the upper surface of the rotary table 1. 32
It is fixed at.

Each annular groove 28 of the swivel joint 28
a, a seal ring 3 above and below 28b, 28c, 28d
3 are fitted to each other to make the space between the swivel joint 28 and the rotary table 1 and the piping manifold 31 liquid-tight. A holding member 34 (FIG. 4) is fixed to the upper end surface of the swivel joint 28 with a bolt 35 to prevent the center of the rotary table 1 from rising. The pressing member 34 is omitted in FIG.

Each communication hole 31a of the piping manifold 31
31b are T joints 37, 37 attached to the mold 2a.
(FIG. 3) are connected to connection ends 37a, 37a by pipes 38, 38 such as copper tubes and hoses, respectively. The connection end 37b of each T joint 37 of the mold 2a is
The connection ends 37a of the T joints 37 of the mold 2b are connected to the respective connection ends 37a of the T joints 37 of the mold 2b by pipes 38, respectively.
a of the mold 2c.
The connection end 37b of the joint 37 is connected to the joint 39 of the mold 2d by a pipe 38, respectively.
The temperature-regulated liquid supplied from the communication hole 31b flows evenly through the molds 2a, 2b, 2c, and 2d as shown by arrows in FIG. 3 and returns to the communication hole 31a.

Mold channel 28 of swivel joint 28
A temperature controller 41 (FIG. 1) is connected to the f and table passages 28h by supply conduits 42 and 43, and a return conduit is connected to the other mold passage 28e and table passage 28g. The temperature controller 41 is connected by 44 and 45. The temperature controller 41 supplies a temperature control liquid such as water or oil to the supply line 4.
2 and 43, and a return line 44,
The temperature control liquid returned through 45 is received and circulated.

Reference numeral 50 denotes a nozzle of an injection unit for injecting the molten resin into the molding cavity of the mold 2. The nozzle 50 shown by a solid line in FIG. 1 and FIG.
However, a structure that moves downward and abuts on the mold 2 (see a two-dot chain line in FIG. 3) may be used.

Next, the operation of the temperature control device of the vertical rotary injection molding machine having the above configuration will be described. The operation of the drive motor 18 causes the rotary table 1 to operate, for example, as shown in FIG.
Is rotated clockwise by 90 degrees, the positioning cylinder 19 is actuated immediately to insert the positioning pin 23 into one positioning hole 1b of the rotary table 1 and to stop the rotary table 1 accurately at a predetermined position. . When the rotary table 1 is positioned, the mold clamping cylinder 9 operates to clamp the set of the molds 2 directly below the movable platen 7. The molten resin is injected from the nozzle 50 into the molding cavity of the mold 2 simultaneously with the completion of the mold clamping of the mold 2.

When the resin filled in the molding cavity is properly solidified, the movable platen 7 is raised by the mold clamping cylinder 9 and the positioning pin 23 is moved downward from the positioning hole 1b by the operation of the positioning cylinder 19. After being pulled out, the drive motor 18 is operated again to rotate the rotary table 1 by 90 degrees and transfer the next mold 2 to the mold clamping position. Hereinafter, the above molding cycle is repeated, which is the same as the conventional one.

In the above molding operation, the temperature controller 41
Sends the temperature to the supply lines 42,43. Supply line 4
The temperature-adjusted liquid sent out to the pipe 2 is supplied to the die channel 28 f of the swivel joint 28, the annular groove 28 b, and the pipe manifold 3.
One of the communication holes 31b and the hose 38 flow in this order and are supplied to each of the molds 2 to control the temperature of each of the molds to a predetermined temperature. The temperature-adjusted liquid working for controlling the temperature of each mold 2 is supplied to the piping manifold 31.
Communication hole 31a, the annular groove 28 of the swivel joint 28
a, the flow path 28 e for the mold and the return pipe 44 flow in this order, and return to the temperature controller 41. The temperature-adjusted liquid sent to the supply pipe 43 is supplied to the table flow path 2 of the swivel joint 28.
8h, the annular groove 28d, and the flow hole 1c (supply hole 1c1, communication hole 1c3, return hole 1c2) flow in this order to control the temperature of the rotary table 1 to a predetermined temperature, and then the annular groove 28c of the swivel joint 28 and the table flow The flow returns to the temperature controller 41 through the line 28g and the return line 45.

In the above, since each hose 38 is disposed outside the rotary table 1, the rotary table 1 is not heated by the temperature control liquid flowing through the hose 38, and the rotary table 1 controls the temperature. Flow hole 1
Since it is directly controlled by the temperature control liquid flowing through c, thermal expansion is well prevented. For this reason, the positioning hole 1b formed in the rotary table does not shift radially outward of the rotary table, and the backlash between the gear 1a of the rotary table 1 and the pinion 21 of the drive motor 18 does not become unnecessarily small. Since the positioning pin 23 is always smoothly inserted into the positioning hole 1b, the driving torque and the noise are not increased. In addition, since the temperature of the peripheral portion of the positioning hole 1b is mainly adjusted, the displacement of the positioning hole 1b and the thermal expansion of the positioning pin 23 are effectively prevented.

In general, hot water is supplied to each mold 2 and cold water is supplied to the rotary table 1 as the temperature control liquid. The temperature of the temperature control liquid supplied to the mold 2 and the rotary table 1 is controlled. The types can be different from each other or the same. The temperature controller 41 in the figure is a two-tank type,
Although the temperature of the temperature control liquid of the mold 2 and the rotary table 1 can be set separately, the temperature controllers 41 of the mold 2 and the rotary table 1 may be separately provided.

In the present invention, the mold clamping device mainly composed of the mold clamping cylinder 9, the rotary driving device mainly composed of the drive motor 18, and the positioning device mainly composed of the positioning hole 1b and the positioning pin 23 are not limited to those shown in the drawings. Various changes are possible. Although the rotary table 1 shown in the drawing is rotated clockwise by 90 degrees, the rotation angle and direction may be other than those described above, and the rotary table 1 is rotated alternately by a predetermined angle in the opposite direction. You may. In order to control the supply amount of the temperature control liquid to each mold 2, each mold 2 is provided with a flow control valve or a flow meter as needed. One or both of the lines 44, 45 can be a supply line and one or both of the other lines 42, 43 can be a return line. Pipe 45 is a supply pipe,
When the conduit 43 is a return conduit, it goes without saying that 1c2 is a supply hole and 1c1 is a return hole.

[0029]

As described above, according to the first aspect of the present invention, a mold is mounted on a rotary table which is intermittently rotated at a predetermined angle about a central axis by a rotary driving device. In the rotary injection molding machine, a ring-shaped pipe manifold having a plurality of communication holes is fixed concentrically with the center axis, and a flow hole is formed in the rotary table. A swivel joint having a plurality of table channels that can communicate with the communication holes of the rotary table and a plurality of mold channels that can communicate with the communication holes of the piping manifold is provided concentrically with the center axis, The invention according to claim 5, wherein each communication hole of the piping manifold and the mold are connected to each other by piping outside the rotary table. The temperature control liquid is supplied to the flow hole of the rotary table and the mold through the flow path for the table and the flow path for the mold, so that the thermal expansion of the rotary table due to the temperature control liquid in the mold is prevented. Therefore, the rotary table can always be accurately positioned, and noise can be prevented with an appropriate driving torque, so that the molding operation can be performed smoothly.

In the temperature control device of the vertical rotary injection molding machine described above, if the flow holes are formed so as to surround the positioning holes near the positioning holes provided in the rotary table, the positioning holes of the rotary table may be formed. Since the temperature of the peripheral portion of the positioning hole is mainly controlled, the thermal displacement of the positioning hole is effectively prevented, and the thermal expansion of the positioning pin inserted into the positioning hole is also prevented.

Further, when the communication hole is constituted by a supply hole, a return hole, and a communication hole of an accessory member detachably attached to the upper or lower surface of the rotary table, the accessory member is removed from the rotary table and the communication hole or the like is removed. Maintenance and inspection can be easily performed, and machining of the circulation hole is facilitated.

In the above temperature control method, when the temperature of the rotary table is lower than that of the mold, the thermal expansion of the rotary table can be more reliably prevented. Further, if the temperature control liquid of the mold and the temperature control liquid of the rotary table are of the same type, even if the temperature control liquid of the mold and the temperature control liquid of the rotary table are mixed due to leakage of the temperature control liquid of the rotary table, there is a great problem. And never.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a temperature control device for a vertical rotary injection molding machine according to the present invention.

FIG. 2 is a schematic plan view of the vertical rotary injection molding machine of FIG.

FIG. 3 is a plan view of a main part of a temperature control device of the vertical rotary injection molding machine according to the present invention.

FIG. 4 is a cross-sectional view taken along a line (IV-IV) in FIG. 3;

FIG. 5 is a sectional view of a portion (VV) in FIG. 3;

FIG. 6 is a sectional view of a portion (VI-VI) in FIG. 3;

FIG. 7 is a sectional view of a portion (VII-VII) in FIG. 3;

FIG. 8 is a sectional view of a portion (VIII-VIII) in FIG. 3;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 rotary table 1a gear 1b positioning hole 1c communication hole 1c1 supply hole 1c2 return hole 1c3 communication hole 1d attached members 2a, 2b, 2c, 2d (2) mold 7 movable platen 9 clamping cylinder 18 drive motor 19 positioning cylinder 21 Pinion 23 Positioning pin 28 Swivel joint 28a, 28b, 28c, 28d Annular groove 28e, 28f Mold flow path 28g, 28h
Table flow path 31 Piping manifold 31a, 31b
Communication hole 37 T-joint 38 Piping 41 Temperature controller 42, 43 Supply pipeline 44, 45 Return pipeline

Claims (7)

(57) [Claims] 1. A vertical rotary injection molding machine in which a mold is mounted on a rotary table that is intermittently rotated around a central axis by a predetermined angle by a rotary drive device, wherein the rotary table includes: A ring-shaped pipe manifold having a plurality of communication holes is fixed concentrically with the center axis and a flow hole is formed, and the center axis has a plurality of table flows that can communicate with the flow holes of the rotary table. Path, a swivel joint having a plurality of mold flow paths that can communicate with the communication holes of the piping manifold is provided concentrically with the center axis, and each communication hole of the piping manifold and the mold, A temperature control device for a vertical rotary injection molding machine, wherein the temperature control device is connected to each other by a pipe outside a rotary table. 2. The temperature control device for a vertical rotary injection molding machine according to claim 1, wherein the circulation hole is formed near the positioning hole provided in the rotary table so as to surround the positioning hole. . 3. The communication hole according to claim 1, wherein the communication hole is constituted by a supply hole, a return hole, and a communication hole of an attached member detachably attached to an upper surface or a lower surface of the rotary table. Temperature control device for vertical rotary injection molding machine. 4. The temperature control device for a vertical rotary injection molding machine according to claim 3, wherein the attachment member is disposed between the positioning hole and the outer periphery of the rotary table. 5. The temperature control device for a vertical rotary injection molding machine according to claim 1, wherein a flow hole of the rotary table is formed through a table flow path and a die flow path of a swivel joint. A temperature control method for a vertical rotary injection molding machine, characterized by flowing a temperature control liquid to a mold. 6. The temperature control method for a vertical rotary injection molding machine according to claim 5, wherein the temperature of the rotary table is lower than that of the mold. 7. The temperature control method for a vertical rotary injection molding machine according to claim 5, wherein the temperature control liquid for the mold and the temperature control liquid for the rotary table are of the same type.