JP4144403B2 - Rotary molding machine and material supply method in the rotary molding machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a molding machine for molding a molded product such as a hollow container, and in particular, a plurality of molds are arranged in a ring on a base, and the molds are fed in a ring while rotating the base. The present invention relates to a rotary molding machine for molding a shaped product and a material supply method in the rotary molding machine.
[0002]
[Prior art]
There is known a rotary molding machine in which a plurality of molds are annularly arranged on a base, and a product having a predetermined shape is molded while rotating the mold together with the base. Such a rotary type molding machine is used, for example, in a method of molding a product such as a hollow container, and in particular, a parison extruded from a die head is received by a pair of split molds, and the mold is closed. It is generally used for blow molding in which air is blown, and then the product is opened by opening the mold (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 52-58671 (see detailed description of the invention in the specification)
[Patent Document 2]
JP 2000-296826 A (see column [0020] in the specification)
[Patent Document 3]
Japanese Unexamined Patent Publication No. 2000-313056 (refer to the detailed description of the invention in the specification)
[0004]
In such a rotary type blow molding machine, a number of split molds are fixed to an annular rail, and each split mold is opened and closed continuously while moving in a ring, and the product of the product is rotated while the annular rail is rotated once. Blow molding is completed after the process is completed. Since a rotary blow molding machine can mold a product with a large number of annular molds, for example, 8 to 14 split molds, it has the advantage of being efficiently molded when mass-producing the same type of product. is there.
[0005]
FIG. 7 is a front view of a main part of a rotary blow molding machine for forming a hollow container.
The rotary blow molding machine includes a molding unit 6 in which a plurality (eight in this embodiment) of molds 220 are arranged at equal intervals on the same circumference, and a predetermined position (station (1)) on the molding unit 6. ) And a product head 8 for taking out a molded product from the mold 220 at a predetermined position (station (7)).
The molding unit 6 is configured by attaching the mold 220 to the annular base 61 at equal intervals, and the mold 220 and the base 61 are driven by the rotation driving unit 65 provided at the center of the base 61 as shown in FIG. Rotates in the clockwise direction.
[0006]
In the above rotary blow molding machine, the parison is supplied from the die head 5 at the station {circle around (1)}, and the upper mold and the lower mold constituting the mold 220 are closed while moving to the stations {circle around (2)} to {circle around (6)}. At one of the stations {circle around (2)} to {circle around (4)}, the blow nozzle 222 is inserted into the mold 220 from the radial direction of the rotation circumference of the base 61, and cooling air is blown into the parison. By this cooling air blow, the parison swells into a shape corresponding to the cavity 221, is cooled, and is taken out by the product take-out unit 8 at the station (7).
[0007]
FIG. 8 is a timing chart showing the opening / closing timing of the mold 220. As shown in the figure, the mold 220 starts to close at the end of the station (1) to which the parison is supplied, and the mold closing is completed by the station (2) where the cooling air is blown. The mold closed state is maintained from station (2) to station (5), during which the molded product is cooled. Then, the mold opening is performed when the station (5) is shifted to the station (6), and this mold opening state is maintained until the mold closing is started in the station (1).
[0008]
By the way, when the operation of the rotary blow molding machine is stopped for a certain period of time by exchanging the mold 220 or the like and then restarted, the first of the material discharged from the die head 5 and the position of the mold 220 are not matched. Shot molded products are discarded as incomplete molded products. Further, immediately after the start of operation, since the discharge amount (discharge speed) of the material discharged from the die head 5 is not stable, several molded products until the discharge amount is stabilized are discarded as adjustment products.
Such an incompletely molded product or an adjusted product is difficult to be automatically taken out by the product take-out unit 8, so that an operator manually takes it out from the mold 220 at station {circle around (6)}.
[0009]
However, such work is troublesome, and in order to secure time and space for manual removal, the mold must be opened at station (6) at the latest as shown in FIG. is there. In order to reduce the molding cost, it is required to increase the rotational speed of the mold 220. However, the cooling time of the molded product in the closed state cannot be secured sufficiently, so that this requirement cannot be sufficiently met. is the current situation.
[0010]
Moreover, in the conventional rotary blow molding machine, if the operation is stopped for inspection or repair, the discharge amount of the material from the material supply unit gradually decreases just before the stop, etc. There is a problem that the molded product is molded as an incomplete molded product. At present, such incompletely molded products are also taken out manually by opening the mold 220 at the station (6).
[0011]
[Problems to be solved by the invention]
The present invention has been made in view of the above-mentioned problems, and without molding an incomplete molded product or an initial adjusted product immediately after the start of operation, a complete molded product can be obtained from the first shot, A highly productive rotary molding machine that does not unnecessarily form an incomplete molded product even when the operation is stopped, and can increase the rotational speed of the mold for a sufficient mold closing period. An object of the present invention is to provide a material supply method in a rotary molding machine.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is formed by annularly arranging a plurality of molds on a base, and sending the molds in a ring as the base rotates, and a material supply unit In a rotary type molding machine that supplies a material to the mold and molds a product of a predetermined shape, when the material is advanced to the material supply unit side, the material supplied from the material supply unit is received, Material pulling means for pulling at a predetermined speed, material cutting means for cutting the material pulled by the material pulling means in the vicinity of the material supply section, and the material pulling means for supplying the material at a predetermined timing And a driving means that allows the material to be supplied from the material supply unit to the mold.
[0013]
According to this configuration, the material discharged from the material supply unit immediately after the start of operation is discharged out of the mold by the material pulling means. And when the quantity of the material discharged from a material supply part is stabilized, the said material tension | pulling means reverse | retreats and supply of the material to a metal mold | die is started.
At this time, the completed molded product can be obtained from the first shot by matching the start timing of material supply with the timing of rotation of the mold. In consideration of the pulling of the material pulled by the mold at the time of molding, the initial adjustment product can be eliminated by pulling while applying tension to the material by the material pulling means.
[0014]
According to the second aspect of the present invention, a plurality of molds are annularly arranged on a base, and the molds are fed annularly with the rotation of the base, and materials are supplied from the material supply unit to the molds. In a rotary molding machine that molds a product of a predetermined shape, a plurality of molds are arranged annularly on a base, and the molds are sent annularly with the rotation of the base, and material supply In a rotary type molding machine that supplies a material from a part to the mold and forms a product of a predetermined shape, a material cutting means that is provided so as to be movable forward and backward with respect to the material supply part, and cuts the material A material pulling means that is provided so as to be movable forward and backward with respect to the material supply unit, and receives the material supplied from the material supply unit when it advances toward the material supply unit, and pulls the material at a predetermined speed; Mold that stops mold rotation When the rolling stop means and the mold rotation stop means are operated, the material cutting means is advanced to the material supply part side to cut the material, and the material tension means is moved to the material at a predetermined timing. Drive means for advancing the supply section and stopping the supply of the material from the material supply section to the mold is provided.
According to this configuration, when the mold rotation stopping unit is operated to stop the rotation of the mold, the material cutting unit is advanced to the material supply unit side at a predetermined timing to cut the material. The material pulling means advances to the material supply unit, receives the material discharged from the material supply unit, and stops the supply of the material to the mold. By doing so, an incompletely molded product is not formed more than necessary.
[0015]
In the invention described in claim 1 or claim 2, various forms are conceivable as the material pulling means. As described in claim 3, it may be a conveyor.
According to a fourth aspect of the present invention, there may be provided a guide for changing the direction of the material discharged from the material supply unit when the material is pulled in one direction by the material pulling means.
This guide always keeps the material discharge direction constant in the vicinity of the material discharge port of the material supply unit, and even if the material is pulled in the lateral direction by the material pulling means, the tip of the material is immediately fixed to the predetermined mold after cutting. Can be directed to a position.
[0016]
According to a fifth aspect of the present invention, it is preferable that a speed at which the material is pulled by the material pulling unit is the same as or faster than the peripheral speed of the mold.
In this way, the material pulling means can pull the material under the same conditions as when the material is supplied from the material supply unit to the mold, and a nearly perfect quality molded product is obtained from the first shot. be able to.
In the rotary molding machine according to the first aspect, the material supply is started by the procedure according to the sixth aspect.
[0017]
That is, the material supply procedure includes a step of presetting a material supply start timing from the material supply unit based on a peripheral speed of the mold, and a time when material discharge is started from the material supply unit. And a step of advancing the material pulling means toward the material supply unit, and a material discharged from the material supply unit is received by the material pulling means, and is equal to or faster than the peripheral speed of the mold. A step of pulling the material in one direction at a speed; a step of cutting the material by the material cutting means after a discharge amount or a discharge speed of the material reaches a preset amount or speed; Cutting the material and retracting the material pulling means at the preset timing to start supplying the material from the material supply unit to the mold.
[0018]
In the rotary molding machine according to the second aspect, the material supply is stopped by the procedure according to the seventh aspect.
That is, the material supply stop procedure includes a step of presetting the material supply stop timing based on the peripheral speed of the mold, and the material rotation stop means when the mold rotation stop means is operated. A step of advancing the pulling means toward the material supply unit side, and a step of rotating a predetermined number of molds after the mold stop means is operated and taking out a molded product in the mold.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of a rotary molding machine according to the present invention will be described with reference to the drawings.
FIG. 1 is a front view of an essential part of a rotary molding machine according to a first embodiment of the present invention.
[0020]
Timing adjustment for adjusting the supply timing of the parison supplied from the die head 5 to the mold 220 immediately after the start of the operation of the rotary molding machine is in the vicinity of the die head 5 as a material supply unit for supplying the parison to the mold 220. A device 7 is provided.
The timing adjusting device 7 receives a base 71 fixed to a fixed portion of the rotary molding machine and a parison discharged from the discharge port 5a of the die head 5, and is faster than the discharge speed of the parison from the die head 5, preferably Is a conveyor 72 as material pulling means for pulling the parison laterally at the same speed as or faster than the peripheral speed of the rotating mold 220, and a parison cutting section for cutting the parison in the vicinity of the discharge port 5a. 73.
In this specification, “circumferential speed” refers to the speed in the tangential direction of the mold 220 on the rotational circumference R of the mold 220 passing through the center of the mold 220.
[0021]
The conveyor 72 supports a motor 721 that is movable in a forward direction approaching the die head 5 and a backward direction away from the die head 5 while being guided by a first guide rail 711 provided on the base 71. A pulley support member 727 extending from the housing to the die head 5 side in parallel with the first guide rail 711 and a rear end (right end in the figure) of the pulley support member 727 so as to be rotatable. A driving pulley 722 that is supported and rotated by driving of the motor 721, a driven pulley 723 that is rotatably supported by the front end (left end in the figure) of the pulley support member 727, the driving pulley 722, and the driven pulley 723 and a belt 724 wound around 723. Therefore, when the motor 721 is driven and the driving pulley 722 rotates, the belt 724 travels clockwise in FIG. 1 along with the rotation of the driven pulley 723.
[0022]
In the vicinity of the front end of the pulley support member 727, an inverted L-shaped support member 725 is erected, and a rotatable roller 726 is attached to the tip thereof. The roller 726 is positioned so as to be positioned almost directly below the discharge port 5a of the die head 5 when the roller 726 moves forward together with the motor 721 and the pulley support member 727, and is attached to the pulley support member 727. When 72 pulls the parison, it serves as a guide roller that changes the direction of the parison discharged from the discharge port 5a.
[0023]
The parison cutting unit 73 cuts the parison discharged from the die head 5 at a preset timing. The parison cutting portion 73 includes a saddle 731 capable of moving forward or backward toward the die head 5 along a second guide rail 712 parallel to the first guide rail 711 of the base 71, and a saddle via a bracket 733. A rod 735 that moves forward and backward in the same direction as the saddle 731 while being guided by a cylinder 732 attached to the saddle 731, a guide 738 provided in the saddle 731, and a guide hole formed in the bracket 733, and a front end of the rod 735 And a cutter 736 provided on the machine. Since the saddle 731 is connected to the casing of the motor 721, the saddle 731 is integrated with the conveyor 72 and moves forward or backward in the same direction.
[0024]
The piston rod 732a of the cylinder 732 can move forward and backward in the same direction as the forward and backward movement of the rod 735, and the tip of the piston rod 732a and the rear end of the rod 735 are connected by a connecting member 734. Therefore, when the cylinder 732 is driven and the piston rod 732a moves forward and backward, the rod 735 and the cutter 736 move forward or backward toward the die head 5 as the piston rod 732a moves.
[0025]
Next, an example of a material supply procedure in the rotary molding machine of the present invention will be described together with the operation of the timing adjusting device 7 with reference to FIGS.
FIG. 2 is a flowchart for explaining the material supply procedure, and FIGS. 3 and 4 are schematic views for explaining the operation of the timing adjusting device 7.
[0026]
First, the timing for supplying the parison discharged from the discharge port 5 a of the die head 5 to the mold 220, that is, the timing for retracting the conveyor 72 and the timing for cutting the parison by the cutter 736 in advance with respect to the rotation timing of the mold 220. Adjust it. For example, the motor driving pulses of the rotation driving unit 65 (see FIG. 7) that rotates the mold 220 are counted, and the best timing for moving the conveyor 72 backward is adjusted, and the timing for driving the cylinder 732 is adjusted. Then, when the mold 220 enters the station (1), the conveyor 72 is moved backward at the timing when the tip of the parison is accurately supplied to the predetermined position of the mold 220, and the parison is cut. To do.
In addition, a necessary and sufficient amount of parison can be supplied to the mold 220 of the station (1) before the mold 220 shifts from the station (1) to the station (2). As described above, the discharge amount (discharge speed) of the parison of the die head 5 is set in advance.
[0027]
The parison discharge timing and discharge amount obtained by the above procedure are unchanged as long as the same mold 220 and the same material parison are used. Therefore, even if the mold 220 is changed or the material of the parison is changed, the rotary molding machine can be operated immediately by simply setting the timing and the discharge amount determined in advance according to the mold 220 and the parison of the material. It is possible to start.
[0028]
As shown in FIG. 3A, in the initial state before the rotary molding machine starts operation, the conveyor 72 of the timing adjustment device 7 and the cutter 736 of the parison cutting unit 73 are in a retracted state separated from the die head 5. It has become.
When the operation of the rotary molding machine is started (step S10), the driving body 713 is driven to advance the conveyor 72 (step S11). As a result, as shown in FIG. 3B, the belt 724 and the roller 726 are positioned directly below the discharge port 5 a of the die head 5.
[0029]
Simultaneously with the advancement of the conveyor 72, the driving of the motor 721 is started and the belt 724 is caused to travel. As described above, it is preferable that the traveling speed of the belt 724 is the same as or slightly higher than the peripheral speed when the mold 220 rotates (step S12).
Thereafter, discharge of the parison P is started from the die head 5 (step S13). The parison P discharged from the die head 5 is pulled laterally by the belt 724 as shown in FIG. 3C (step S14). At this time, the roller 726 positioned directly below the discharge port 5a serves as a guide, and the parison P changes its direction by the roller 726, reaches the rear end of the conveyor 72 together with the belt 724, and is discharged from the machine.
[0030]
The discharge amount (discharge speed) of the parison P is detected by a sensor or the like (not shown). Then, when the discharge amount (discharge speed) of the parison reaches a preset value (step S15), the mold 220 of the rotary molding machine starts to rotate (step S16).
At the same time, the temperature rise of the cutter 736 is started (step S17).
After the temperature of the cutter 736 is sufficiently raised, as shown in FIG. 4A, the cylinder 732 is driven to cut the parison P with the cutter 736 (step S18). The cutting of the parison P by the cutter 736 is performed intermittently until a first blow button (not shown) for starting the supply of the parison P to the mold 220 is operated (steps S19 and S20).
[0031]
When the first blow button is operated (step S19), the parison P is cut by the cutter 736 at a preset timing, and the parison cutting section reaches a position where it does not interfere with the parison P discharged from the discharge port 5a. 73 and the conveyor 72 move backward (step S21). Then, the parison is supplied from the die head 5 to the mold (step S22). The timing is set in advance so that the tip of the parison P is accurately supplied to a predetermined position of the mold 220 of the station (1), so that a complete molded product can be obtained from the first shot. it can.
[0032]
According to the rotary molding machine of this embodiment, a complete molded product can be molded from the first shot, and an incomplete molded product or an adjusted product is not molded. It is not necessary to remove the molded product or the adjusted product. Therefore, there is an advantage that the mold closing period can be lengthened.
FIG. 5 is a timing chart showing the opening / closing timing of the mold 220. As shown in the figure, the mold opening may be started at the end of the station (6), and the mold closing period is made longer by the rotation angle α than the mold opening timing in the conventional rotary molding machine shown in FIG. be able to.
[0033]
This indicates that the rotation speed of the mold 220 can be increased by the rotation angle α. In this embodiment, the angle of the mold closing period which was initially 205 ° could be extended to 225 ° (α = 20 °), and the rotation speed of the mold 220 could be increased by about 10%. .
Thus, in the rotary molding machine of this embodiment, the rotational speed of the mold 220 can be increased to increase the productivity of the molded product.
[0034]
Next, a second embodiment of the present invention will be described with reference to FIG.
In the first embodiment described above, the timing adjustment device 7 is used to measure the timing of parison supply from the die head 5 to the mold 220, so that the first shot incompletely molded product at the start of operation of the rotary molding machine. In addition, the initial adjustment product is prevented from being molded.
In the second embodiment, the same device as the timing adjustment device 7 of the first embodiment is used so that an incompletely molded product is not formed more than necessary when the rotation of the mold 220 is stopped.
[0035]
As shown in FIG. 6A, when the mold 220 is rotated and the molded product is being molded, the conveyor 72 and the parison cutting portion 73 of the timing adjusting device 7 are in the retracted position, and the die head 5 The parison discharged from is supplied to the mold 220.
When, for example, an operator operates an operation button (die rotation stop means, not shown) for stopping the rotation of the mold 220 due to the production stop or the like, as shown in FIG. First, cut the parison with the cutter 736,
The conveyor 72 of the timing adjustment device 7 moves forward, and the parison discharged from the die head 5 is received by the belt 724.
[0036]
When the rotation of the mold 20 is stopped, the parison is first cut by the cutter 736, so that an incompletely formed product is not formed more than necessary, and only one incompletely formed product is formed.
After the operation button is operated, the mold 220 continues to rotate for a while, and after all the molded products in the mold 220 are taken out by the product take-out unit 8 (see FIG. 7) in the station (7). Then, the operator manually removes the last one incomplete molded product from the mold and stops.
[0037]
Although preferred embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments.
For example, in the above description, as a pulling means for pulling the parison, a belt conveyor composed of a belt and a pulley has been described as an example. However, the parison can be pulled out with a predetermined tension and a predetermined speed and discharged outside the apparatus. If possible, it is not limited to a belt conveyor, and may be a roller conveyor in which a large number of rollers are arranged in the pulling direction. In addition, other means such as a rotating roller may be used.
Furthermore, the hollow container molding has been described as an example, but the present invention can be applied to other molded articles as long as they are molded by a rotary molding machine in the same procedure as the hollow container. is there.
[0038]
【The invention's effect】
As described above in detail, according to the present invention, after the operation of the rotary molding machine is stopped by exchanging the mold or the like, a complete molded product can be molded from the first shot when the operation is started. Therefore, there is no need to form useless incomplete moldings and adjustments, and there is no need to remove incomplete moldings and adjustments from the mold of the rotary molding machine. The operating rate of the machine can be increased.
[0039]
In addition, since it is not necessary to take out incompletely molded products and adjusted products from the mold of the rotary molding machine, the rotational speed of the mold can be increased while ensuring a sufficient mold closing period, which increases the productivity of the molded product. Can be increased.
In addition, when the rotation of the mold is stopped, the mold stops after the complete molded product is formed in the final shot, so the incomplete molded product is not formed more than necessary, and the incomplete molding is performed manually. For example, only one product can be taken out, and the productivity of the molded product can be increased.
[Brief description of the drawings]
FIG. 1 is a front view of an essential part of a rotary molding machine according to a first embodiment of the present invention.
FIG. 2 is a flowchart illustrating a material supply procedure.
FIG. 3 is a schematic diagram illustrating the operation of the timing adjustment device.
FIG. 4 is a schematic diagram for explaining the operation of the timing adjustment device continued from FIG. 3;
FIG. 5 is a timing chart showing the opening / closing timing of the mold in the present invention.
FIG. 6 is a schematic view illustrating the operation of the rotary molding machine according to the second embodiment of the present invention.
FIG. 7 is a front view of a main part of a conventional example of a rotary blow molding machine for forming a hollow container.
FIG. 8 is a timing chart showing the opening / closing timing of a mold in a conventional example of the present invention.
[Explanation of symbols]
7 Timing adjustment device 71 Base 711 First guide rail 712 Second guide rail 713 Drive body 72 Conveyor 721 Motor 722 Drive side pulley 723 Drive side pulley 724 Belt 725 Support member 726 Roller 727 Pulley support member 73 Parison cutting part 731 Saddle 732 Cylinder 732a Piston rod 733 Bracket 734 Connecting member 735 Rod 736 Cutter

Claims (7)

A plurality of molds are annularly arranged on a base, and the molds are sent in a ring as the base rotates, and materials are supplied from the material supply unit to the mold to form a product of a predetermined shape. In a rotary molding machine that performs
A material pulling means which is provided so as to be movable forward and backward with respect to the material supply unit, and receives the material supplied from the material supply unit and pulls it at a predetermined speed when it advances toward the material supply unit;
A material cutting means for cutting the material pulled by the material pulling means at a predetermined timing in the vicinity of the material supply unit;
Drive means for allowing the material pulling means to retreat from the material supply unit at a predetermined timing and enabling the material supply from the material supply unit to the mold;
A rotary molding machine characterized by comprising: A plurality of molds are annularly arranged on a base, and the molds are sent in a ring as the base rotates, and materials are supplied from the material supply unit to the mold to form a product of a predetermined shape. In a rotary molding machine that performs
A material cutting means which is provided so as to be movable forward and backward with respect to the material supply unit, and cuts the material;
A material pulling means which is provided so as to be movable forward and backward with respect to the material supply unit, and receives the material supplied from the material supply unit and pulls it at a predetermined speed when it advances toward the material supply unit;
Mold rotation stopping means for stopping rotation of the mold;
When the mold rotation stopping means is operated, the material cutting means is advanced to the material supply part side to cut the material, and the material tensioning means is advanced to the material supply part at a predetermined timing. Driving means for stopping the supply of the material from the material supply unit to the mold;
A rotary molding machine characterized by comprising: The rotary molding machine according to claim 1 or 2, wherein the material pulling means is a conveyor. The guide for changing the direction of the material discharged from the material supply unit when the material is pulled in one direction by the material pulling means is provided. The rotary molding machine described in 1. 5. The rotary molding machine according to claim 1, wherein a speed at which the material is pulled by the material pulling unit is equal to or faster than a peripheral speed of the mold. A method for supplying a material in the rotary molding machine according to claim 1,
A step of presetting a material supply start timing from the material supply unit based on the peripheral speed of the mold;
A step of advancing the material pulling means toward the material supply unit when discharging of the material from the material supply unit is started;
Receiving the material discharged from the material supply unit by the material pulling means, and pulling the material in one direction at the same speed as the peripheral speed of the mold or at a speed faster than the peripheral speed;
A step of cutting the material by the material cutting means after the discharge amount or discharge speed of the material reaches a preset amount or speed;
Cutting the material, retreating the material pulling means at the preset timing, and starting the material supply from the material supply unit to the mold; and
A material supply method in a rotary molding machine. A method of supplying a material in the rotary molding machine according to claim 2,
Based on the peripheral speed of the mold, presetting the material supply stop timing;
A step of advancing the material pulling means toward the material supply unit at the stop timing when the mold rotation stopping means is operated;
A step of rotating a predetermined number of molds after the mold stop means is operated, and taking out a molded product in the mold; and
A material supply method in a rotary molding machine.

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