JP3165491B2 - Rotary molding system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary molding system. The present invention relates to a rotary molding system capable of shortening a molding cycle by heating well.

[0002]

2. Description of the Related Art Various techniques for molding optical plastic parts with high precision have been developed. Conventionally, such techniques are disclosed in, for example, Japanese Patent Application Laid-Open No. 64-3642.
No. 1, JP-A-2-38012 and JP-A-1-38012
No. 139231. In each of these techniques, the molten resin is injected and filled into the cavity of an injection mold heated and heated to a temperature above the glass transition point (for example, about 140 ° C. for polycarbonate), and then the injection mold is subjected to glass transition. The molded product is taken out by gradually cooling it to a temperature below the temperature, specifically, a heat deformation temperature (for example, about 130 ° C. for polycarbonate).

In plastic injection molding, the steps of cooling and curing the resin injected by an injection molding machine on the spot, taking out the cured resin and injecting the next resin are taken. The molding machine cannot be used for the injection of the next resin until the resin is cured, so that the use efficiency is poor, and problems such as curing of the resin in the exit passage of the injection molding machine occur.

[0004] For this reason, a plurality of injection molds are facilitated,
A variety of rotary molding systems have been developed in which a mold from which a resin has been injected by an injection molding machine is transferred to another location and cooled there, and at the same time, the resin is immediately injected into the next mold by the injection molding machine. This rotary injection molding system is provided with a heating station for heating the mold before performing injection molding. The heating station has a plurality of heating stages having a heating means, and the mold is conveyed to the heating stage and heated by the heating means to quickly and uniformly heat the mold.

Conventionally, as an injection molding system having this type of heating means, for example, one described in Japanese Utility Model Laid-Open No. 2-22811 is known, and is shown in FIGS. In FIG. 4, reference numeral 1 denotes an injection molding die having support portions 1a and 1b at both ends of upper and lower end surfaces, respectively, and has a cavity (not shown) in which molten resin can be injected and filled.

[0006] Heater plates 2a to 2d are provided on the left, right, upper and lower surfaces of the mold 1 so as to be in contact with and separate from the entire area of the upper, lower, left and right sides of the mold 1, respectively. 2d is operated by an air cylinder (not shown) and has a heater inside. Also, mold 1
Guide members 3a and 3b are disposed on both sides of the support portion 1a of the upper heater plate 2 and the guide members 3a and 3b.
a, which guides the mold 1 to the heating stage.

The guide members 3a and 3b are provided with transport rollers 4a and 4b, respectively.
b is rotatably abutted on the support portion 1a to guide the mold 1 to a space defined by the heater plates 2a to 2d. The guide rollers 3a and 3b have support rollers 5 attached thereto.
a, 5b, and the support rollers 5a, 5b
Is designed to stably support the mold 1 by restricting the mold 1 from swinging in the left-right direction in the figure.

In the heating means having such a configuration, the mold 1 is transported by the transport rollers 4a and 4b to the heater plate 2
After being guided to the space defined by a to 2d, the mold 1 is heated to a predetermined temperature by bringing the heater plates 2a to 2d preheated by the heater into contact with the mold 1. After heating, the heater plates 2a to 2d are separated from the mold 1, and the mold 1 is guided from the heating station to the next injection / filling station by the transport rollers 4a and 4b.

In this case, the heater plates 2a to 2d
Heat can be directly transmitted to the mold 1, the efficiency of temperature rise of the mold can be improved, and accurate temperature control of the mold can be performed. In addition, since it is not necessary to embed the heater in the mold 1, it is not necessary to connect the heater inside the mold 1 to an external power supply, and it is possible to prevent a short circuit or the like from occurring. The effect can be obtained.

On the other hand, the one shown in FIG. 5 is provided with heater plates 7a and 7b on both left and right sides of the mold 6, and guide members 8 on both sides of a support 6a provided on both sides of the lower end of the mold 6.
a and 8b are arranged. This guide plate 8
Rollers 9a and 9b for transporting the mold 6 and rollers 10a and 10b for supporting the mold 6 are also provided on a and 8b, and the same effects as those described above can be obtained.

[0011]

However, in the heating means of such a conventional rotary molding system, the rollers 4a, 4b, 5a, 5b, 9a, 9b, 10
a and 10b are heater plates 2a to 2d and heater plates 7a and 7
b, the heater plate 2a
2d, heat energy applied to the molds 1 and 6 from the heater plates 7a and 7b escaped to the outside via the rollers 4a and 4b.

That is, the rollers 4a, 4b, etc.
Since the temperature is lower than a to 2d, the heat energy applied to the dies 1 and 6 escaped to the outside via the low-temperature rollers 4a and 4b. For this reason, in precision injection molding, the dies 1 and 6 cannot be heated uniformly, although the temperatures of the dies 1 and 6 must be made as uniform as possible. There was a problem that would. In addition, since heat is released from the rollers 4a, 4b, etc., there is a problem that the heating time of the dies 1, 6 becomes longer by that much, and the molding cycle becomes longer. In addition to this, a large amount of electric energy of the heater is required for the amount of heat released, so that there is a problem that the cost of the molded product increases.

On the other hand, in the heating means shown in FIG.
If the timing at which the upper and lower heater blocks 2a, 2b are brought into contact with the mold is not controlled with high precision, the conveying rollers 4a, 4b
If the length is long in the vertical direction, the rollers 4a and 4b may be broken. That is, if the upper heater plate 2a comes into contact with the mold 1 earlier than the lower heater plate 2b, the contact force of the upper heater plate 2a is directly applied to the rollers 4a and 4b. 4b may be destroyed. In addition, if the right and left heater plates 2c and 2d are not similarly controlled with high accuracy, there is a possibility that the support rollers 5a and 5b may be broken.

[0014] Further, even in the case of FIG.
If the heater plates 7a and 7b are not controlled with high precision,
10a and 10b could be destroyed. In particular, since the transport rollers 4a and 4b and the transport rollers 9a and 9b also receive the weight of the dies 1 and 6, the possibility of breakage is higher than that of the support rollers 5a and 5b and the like. , 6 could not be successfully transferred.

The reason why the contact timing of the heater plates 7a and 7b is adjusted with high precision in this manner is that as shown in FIG. 6, the stronger the bonding force to the mold (ie, the stronger the fastening force of the heater plate), the more. This is because the heating time of the mold can be reduced, and in the conventional example, when the bonding force is improved,
The risk of breaking the rollers 4a, 4b, etc. is further increased,
There is a problem that the molding cycle cannot be shortened by shortening the heating time.

Therefore, according to the first aspect of the present invention, it is possible to prevent the quality of a molded product from deteriorating by uniformly heating a mold, shorten the molding cycle, and reduce the cost of the molded product. It is intended to provide a rotary molding system that can be designed. Claim 2
The described invention prevents the transport roller from being destroyed, and allows the temperature adjusting member to be joined to the mold with a strong force, so that the mold can be transported reliably and the heating time of the mold can be reduced. It is an object of the present invention to provide a rotary molding system that can be shortened to further shorten the molding cycle.

[0017]

According to the first aspect of the present invention,
In order to solve the above-mentioned problem, a plurality of injection molds having a cavity capable of injecting and filling a molten resin and having support portions at both ends of a predetermined end surface are provided with a heating device provided separately from an injection / filling station. Heating at the station,
In a rotary molding system for transferring a mold to an injection / filling station after heating to form a molded article, the heating station has at least one heating stage having a first temperature adjusting means and a second temperature adjusting means. A first temperature equalizing stage having at least one stage, wherein the first and second temperature adjusting means have an abutment surface provided so as to be able to abut and separate from the surface of the mold, and a plurality of temperatures for adjusting the temperature of the mold; An adjusting member;
A conveying member provided integrally with the temperature adjusting member at at least one end portion of the temperature adjusting member and conveying the injection molding die in contact with the support portion; And a support member provided integrally with the means and supporting the injection molding die in contact with the support portion.

According to a second aspect of the present invention, in order to solve the above-mentioned problem, a predetermined gap is formed between the contact surface of the temperature adjusting member and the surface of the mold during the transportation of the injection mold. And the contact surface of the temperature adjustment member is brought into contact with the surface of the mold during heating and soaking of the mold to form a gap between the support portion and the transport member. It is characterized by.

[0019]

According to the first aspect of the present invention, the transport member and the support member are integrally provided on the temperature adjusting member. Therefore, the heat of the mold is not released to the outside from the conveying member or the like, and the mold is heated uniformly, and a precise injection molding operation is performed, thereby improving the quality of the molded product. In addition, since heat is not released from the conveying member or the like, the heating time does not increase, and the molding cycle is shortened. In addition, a large amount of electric energy of the heater is not required because heat is not released, and the cost of the molded product does not increase.

Further, the heating station has at least one heating stage having first temperature adjusting means and at least one heating stage having second temperature adjusting means. Therefore, the mold is uniformly and quickly heated so that a temperature gradient does not occur in the heating stage and the soaking stage. According to the second aspect of the invention, the transfer member is brought into contact with the support portion during the transfer of the mold, and a gap is formed between the support portion and the transfer member when the mold is heated and soaked. Therefore, even when the temperature adjustment member is in contact with the mold, the transport member does not contact the support portion, and the temperature adjustment member is joined to the mold with a strong force. As a result, the transport rollers are not likely to be damaged, and the mold is transported reliably.
Further, since the transport roller is strongly bonded to the mold, the heating time of the mold is shortened, and the molding cycle is further shortened.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments.
1 to 3 are views showing one embodiment of a rotary molding system according to the present invention. First, the configuration will be described. In FIG. 1, reference numeral 11 denotes a plurality of injection molds, 12 denotes a heating station for heating the mold 11, and 13 denotes an injection / mold for injecting / filling a molten resin into a cavity (not shown) in the injection mold 11.
Filling station, 14 is a slow cooling station for gradually cooling the plurality of molds 11 into which the molten resin has been injected and filled, 15 is a take-out station for taking out formed products from the mold 11 after slow cooling, and 16 is each station 12 to 15 Is a transport path for connecting.

The above-described heating station 12 has a heating stage 12a, a soaking stage 12
b, a heating stage 12c is provided, the set temperature of the first heating stage 12a is set to be higher than the mold 11 at the time of injection and filling, and the heating stage 12c provided in the second stage
Is set to be the same as the temperature of the mold 11 during injection and filling.

FIG. 2 is a block diagram of the first temperature adjusting means 21 provided on the heating stages 12a and 12c. The first temperature adjusting means 21 is a heater block as a temperature adjusting member opposed to each other with the mold 11 interposed therebetween. 22 to 25. The heater blocks 22 to 25 have an abutment surface that can be in contact with and separated from the surface of the mold 11, and the length in the paper direction is substantially the same as or slightly longer than the length in the paper surface of the mold 11. I have.

The mold 11 has a substantially rectangular parallelepiped shape composed of an upper mold 26a and a lower mold 27, and a cavity (not shown) taking the shape of a molded product is formed on the contact surface between the upper mold 26 and the lower mold 27. A well-known sprue not shown in the cavity,
The molten resin is injected and filled through a runner and a gate. Then, after filling the molten resin, the upper mold 26 and the lower mold 27 are released, so that a molded product is taken out from the cavity. Also,
Support portions 26 are provided at both ends of the upper and lower end surfaces of the upper mold 26 and the lower mold 27.
a, 27a are formed, and the support portions 26a,
Recesses 26b and 27b are formed in the upper and lower portions of 27a.

On the other hand, each of the heater blocks 22 to 25 is operated by a hydraulic cylinder (not shown).
The cylinder abuts and separates from the mold 11 so that the joining force can be varied at the time of abutment. A heater and a thermocouple are embedded in each of the heater blocks 22 to 25, and the heater is controlled by calculating a difference between a temperature measured by the thermocouple and a set temperature by a temperature controller (not shown). Then, the temperature of each of the heater blocks 22 to 25 is controlled.

The lower heater block 23 is provided with a heat-resistant position sensor (not shown) for detecting that the mold 11 has entered the space between the heater blocks 22 to 25. The controller outputs a signal to a controller (not shown). When the controller inputs the signal, the controller activates the hydraulic cylinder and heats the mold for a predetermined time by an internal timer.

On the other hand, the upper heater block 22 is formed to have a substantially U-shaped cross section, and transport rollers 28a and 28b as transport members such as cam followers are integrally provided on the inner periphery of both ends. The transport rollers 28a and 28b are inserted into the concave portions 26b and abut against the support portions 26a from below, so that the mold 11 is transported into the heating stations 12a and 12c.

In the vicinity of the transport rollers 28a and 28b, support rollers 29a and 29b as support members such as cam followers are provided fixedly with the upper heater block 22, and these support rollers 29a and 29b support the rollers. The mold 11 is in contact with both sides of the portion 26a to restrict the mold 11 from swinging in the left-right direction in the drawing. For this reason, the mold 11 includes the transport rollers 28a and 28b and the support rollers 29a,
It is guided to the space defined by the heater blocks 22 to 25 by being guided by 29b.

The heater blocks 22 to 25 are separated from the mold 11 so that the mold 11 can easily enter the space before the mold 11 enters the space.
A gap c is formed between the lower heater block 23 and the mold 11 when the holder 11 is held. Also, both ends of the upper heater block 22 extend downward,
When the mold 11 is held by the heater block 22, a predetermined gap a is formed between the contact surface of the mold 11 and the contact surface of the heater block 22. And the recess 26a
Is formed to have a predetermined width b, and the widths a, b, and
c has a relationship of b>a> c. Therefore, the mold 11
The rollers 28a and 28b are brought into contact with the support portions 26a during the transfer of the mold, and the heater block 22 is moved by the mold 11 when the mold is heated.
As shown in FIG. 3, the support portion 26a and the transport roller
A gap is formed between 28a and 28b.

On the other hand, the temperature equalizing stage 12b is provided with a second temperature adjusting means, and this temperature adjusting means is such that the heater blocks 22 to 25 in the temperature adjusting means 21 shown in FIGS. In addition, the heater is not embedded in the heat insulating plate, so that the heat of the mold 11 is prevented from being released to the outside when the heat comes into contact with the mold 11. Next, the operation will be described.

First, in each of the stages 12a to 12c, the heater blocks 22 to 25 and the heat insulating plate are separated from each other so as to be larger than the shape of the mold 11. Next, the mold 11 is moved from the unloading station 15 to the transfer path by a mold transfer device (not shown).
After being transported to the heating station 12 via the heating roller 16, it is first transported to the heating stage 12 a, where the transport rollers 28 a and 28 b
While being stably guided by the support rollers 29a and 29b, the vehicle enters the space defined by the heater blocks 22 to 25 and stops.

At this time, since the position sensor detects the mold 11, the control unit operates the timer and the hydraulic cylinder to lower the upper heater block 22 to contact the mold 11. At this time, each gap a, b, c
Since the relationship of>a> c is satisfied, after the mold 11 abuts on the lower heater block 23, the upper heater block 22 further descends to separate the transport rollers 28a and 28b from the support portion 26a. After a gap is formed between the support block 26a and the supporting portion 26a, the gap is further widened and further lowered to bring the contact surface of the heater block 22 into contact with the surface of the mold 11. For this reason, even if the heater block 22 is firmly joined to the mold 11, the transport rollers 28a,
28b is not broken.

Next, the left and right heater blocks 24 and 25 are brought into contact with the mold 11 as shown in FIG. 3, and these heater blocks 22 to 25 are firmly joined to the mold 11 by a hydraulic cylinder, thereby joining the mold 11 to each other. Heat. Next, the timer operates for a predetermined time, and when the temperature of the mold 11 is heated to a target temperature, that is, a temperature higher than the temperature of the mold 11 at the time of injection and filling, the left and right heater blocks 24, 25, The upper heater block 22 is sequentially separated from the mold 11. When the upper heater block 22 is raised, the support portion 26 is moved by the transport rollers 28a, 28b.
And the mold 11 is separated from the lower heater block 23. Next, while holding the mold 11 by the upper heater block 22, the mold is transferred to the soaking stage 12b by the mold transfer device.

In the soaking stage 12b, the heat insulating plate is brought into contact with the mold 11 by the same operation as described above,
In a, the temperature gradient of the mold 11 is removed while preventing the heat energy given to the mold 11 from being released into the air. Then, when the temperature gradient of the mold 11 is removed and the target injection mold temperature is reached, the heat insulating plate is separated from the mold, and
While holding the mold 11 by 28a, 28b and support rollers 29a, 29b, the heating stage 12 is
c. The heating stage 12c is heated by the same operation as the above-described heating stage 12a so that the temperature of the mold 11 becomes the mold temperature at the time of injection and filling.

After heating, the heater blocks 22 to 25 are again placed in the mold.
After being separated from the mold 11, the mold 11 is conveyed to the injection / filling station 13 via the conveyance path 16 by the mold conveying device, and the station 13 injects and fills the molten resin into the cavity. As described above, in the present embodiment, the transport rollers 28a are provided on the upper heater block 22 and the upper heat insulating plate.
28b and the supporting rollers 29a, 29b are integrally provided, so that the heat of the mold 11 is prevented from being released to the outside from the transport rollers 28a and the like, so that the mold 11 can be uniformly heated, and precision Injection molding operation can be performed. As a result, the quality of the molded product can be improved.

Further, since heat can be prevented from being released from the transport rollers 28a and the like, the heating time can be shortened and the molding cycle can be shortened. In addition to this, the electric energy of the heater can be reduced as much as the heat is not released, and the cost of the molded product can be reduced. Further, the heating station 12 has two heating stages 12 a and 12 c having the first temperature adjusting means 21.
And a one-stage soaking stage 12b having a second temperature adjusting means.
Therefore, it is possible to prevent the temperature gradient from occurring in the heating stages 12a and 12c and the soaking stage 12b, and to heat the mold 11 uniformly and quickly.

When the mold 11 is transported, the transport rollers 28a, 28
b is brought into contact with the support portion 26a, and a gap is formed between the support portion 26a and the transport rollers 28a and 28b when the mold 12 is heated and soaked. Can be prevented from contacting the support rollers 26a and 28b even when the heater block 22
Can be bonded to the mold 11 with a strong force. As a result, the transport rollers 28a and 28b can be prevented from being damaged, and the die 11 can be transported reliably. Further, since the transport rollers 28a and 28b can be strongly bonded (fastened) to the mold 11, the heating time of the mold 11 can be reduced as shown in FIG. 6, and the molding cycle can be further shortened. it can.

In this embodiment, the heater blocks 22 to
Although a hydraulic cylinder is used to operate 25, an air cylinder may be used. In addition, the terms heating and soaking in this embodiment mean not only heating a cold thing but also keeping a warm thing warm.

[0039]

According to the first aspect of the present invention, it is possible to prevent the heat of the mold from being released to the outside from the conveying member or the like, and to precisely heat the mold to perform a precise injection molding operation. Can be performed. As a result, the quality of the molded product can be improved. Further, since heat can be prevented from being released from the conveying member or the like, the heating time can be shortened, and the molding cycle can be shortened. In addition to this, the electric energy of the heater can be reduced as much as the heat is not released, and the cost of the molded product can be reduced.

Further, since the heating station has at least one heating stage having the first temperature adjusting means and at least one heating stage having the second temperature adjusting means, The mold can be heated uniformly and quickly so that a temperature gradient does not occur on the stage. According to the second aspect of the present invention, even when the temperature adjusting member abuts on the mold, the conveying member does not abut on the supporting portion, so that the temperature adjusting member can be joined to the mold with a strong force. it can. As a result, the transport rollers can be prevented from being damaged, and the mold can be transported reliably. Further, since the transport roller can be strongly bonded to the mold, the molding time can be shortened by shortening the heating time of the mold.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of an injection molding system according to the present invention.

FIG. 2 is a sectional view of a temperature adjusting unit in the injection molding system in FIG.

FIG. 3 is a cross-sectional view showing a state in which a temperature adjusting unit in FIG. 2 is in contact with a mold.

FIG. 4 is a sectional view of a conventional heating means.

FIG. 5 is a sectional view of a conventional heating means.

FIG. 6 is a graph showing the relationship between temperature and time in the fastening force of the mold.

[Explanation of symbols]

 11 Injection Mold 12 Heating Station 12a, 12c Heating Stage 12b Heat Equalizing Stage 13 Injection / Filling Station 21 First Temperature Adjusting Means 22-25 Heater Block (Temperature Adjusting Member) 26a Support 28a, 28b Transport Roller (Transportation Member) 29a, 29b Support roller (support member)

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hisaaki Koseko 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Toshiharu Hatakeyama 1-3-6 Nakamagome, Ota-ku, Tokyo No. Ricoh Co., Ltd. (72) Kinichi Oikawa, Inventor 109, Ohata Tenth Land, Hanamaki-shi, Iwate Prefecture Ricoh Optical Co., Ltd. (56) References JP-A-8-39642 (JP, A) -22811 (JP, U) JP-A-3-112318 (JP, U) Patent 3103393 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 45/00-45/84

Claims (2)

(57) [Claims] 1. A plurality of injection molding dies having a cavity capable of injecting and filling a molten resin and having support portions at both ends of a predetermined end surface are heated by a heating station provided separately from the injection and filling station. In a rotary molding system for transferring a mold to an injection / filling station after heating to form a molded article, the heating station includes at least one heating stage having a first temperature adjusting means, and a second temperature adjusting means. A plurality of stages for adjusting the temperature of the mold, wherein the first and second temperature adjusting means have a contact surface provided so as to be able to contact and separate from the surface of the mold. A temperature adjusting member, a conveying member provided integrally with the temperature adjusting member at at least one end portion of the temperature adjusting member, and abutting on the supporting portion to convey the injection molding die; Rotary molding system, characterized in that it consists in proximity to feed member provided integrally with the temperature adjusting means, a support member for supporting the injection mold in contact with the support portion. 2. When the injection molding die is transported, a predetermined gap is formed between the contact surface of the temperature adjusting member and the surface of the die to bring the transport member into contact with the supporting portion, and when the die is heated. 2. The rotary molding system according to claim 1, wherein a contact surface of the temperature adjusting member is brought into contact with the surface of the mold during the soaking to form a gap between the supporting portion and the conveying member.