KR100958592B1 - Temperature control method of injection molding device - Google Patents

Abstract

The present invention relates to a two-step temperature rise control method of an injection molding machine nozzle,

The cylinder heating heater and the nozzle heating heater are operated simultaneously to simultaneously heat the heating cylinder and the nozzle, respectively, and simultaneously raise the temperature.The heating temperature of the nozzle, which is heated faster than the heating cylinder, is lower than the final control target temperature of the nozzle molding temperature setting part. When the temperature range of the preliminary temperature set section preset in the temperature range is reached, the nozzle heating heater is controlled until the heating temperature of the heating cylinder reaches the preliminary temperature setter to control the heating temperature of the nozzle and the preliminary temperature setter. A preheating step of maintaining the same temperature range;

Heated by the cylinder heating heater that is heated from the start of the pre-heating step, the nozzle heating heater to be heated again from the time the heating temperature of the heating cylinder is heated to a temperature higher than the temperature range of the preliminary temperature setting unit Each of the cylinder heating nozzle and the nozzle heating heater heats the heating cylinder and the nozzle at the same time, so that the temperature rises to the temperature range of the cylinder temperature setting unit and the nozzle forming temperature setting unit, which are the final control target temperatures of the heating cylinder and the nozzle, respectively. The invention is characterized in that it is configured to control the heating operation to increase the temperature to the nozzle forming temperature which is the final control target temperature of the nozzle by forming a set temperature heating step to be made in such a time zone.

Injection molding machine, heating cylinder, nozzle, heater, preheating stage, set temperature heating stage, cylinder temperature setting unit, nozzle molding temperature setting unit, synchronous heating

Description

Temperature control method of injection molding machine nozzle {Temperature control method of injection molding device}

The present invention prevents the occurrence of overheating or deterioration of the material present in the nozzle by controlling the heating temperature rise of the nozzle constituting the injection device of the injection molding machine in a stepwise manner with respect to the heating cylinder heating temperature. The present invention relates to a two-step temperature rise control method of an injection molding machine nozzle to prevent defects and contribute to stable molding.

In general, as a method for controlling the heating temperature of the material when the material (resin) injected into the nozzle and the heating cylinder of the injection molding machine is melted, the entire section of the heating cylinder (front, middle, rear) and the nozzle are heated. In order to control the temperature, there is a simultaneous operation control method that increases the temperature by uniformly controlling the heating temperature of the heating cylinder and the entire nozzle by simultaneously operating the heater mounted on the heating cylinder and the heater mounted on the nozzle at the same time. Method of starting the temperature rise of the nozzle after reaching the set temperature for every section (front part, middle part, rear part) and method of starting the temperature rise of the nozzle after the heating temperature of the front part of the heating cylinder reaches the set temperature and heating If the time is delayed by the delay timer from the start of cylinder temperature rise and the timer out signal drops, The differential control method, including the method of initiation is used.

When controlling the temperature rise of the heating cylinder heater and the temperature rise of the nozzle heater at the same time according to the simultaneous operation control method of the prior art, the time required for the temperature rise of the furnace wire is small (the outer diameter is short and the length is short). On the other hand, since the entire section of the heating cylinder is formed with a relatively long outer diameter and a longer length than the nozzle, the time required for the temperature rise of the heating cylinder becomes longer, so that gasification, deterioration, and carbonization of the material injected into the nozzle As a result, a problem of abnormally deteriorating the state of the material occurs, which causes a defect of the product.

That is, in the conventional simultaneous operation control method, as shown in FIG. 4, it takes a short time to heat up the material staying in the nozzle 100 to the temperature of the nozzle molding temperature setting unit 110. Since the time it takes for the material to stay in the heating rises to the temperature of the heating cylinder temperature setting section 210 becomes longer, the time period during which the material of the nozzle 100 rises to the nozzle molding temperature setting section 110 and the heating cylinder 200 ) Is a phenomenon that the material existing in the nozzle 100 is continuously heated during the time of the heating time extension (Time lug) is formed between the time zone that the material of the temperature rises to the heating cylinder temperature setting unit 210. As a result, deterioration and carbonization of the material present in the nozzle 100 may occur, and gas may be generated.

In the conventional parallax control method, the heating of the temperature rise control time of the nozzle 100 is slightly delayed as compared to the heating cylinder 200 in order to prevent the material (resin) from staying at a high temperature for a long time. Although it is a method of forming a time delay, this is because the temperature of the material 100 of the nozzle 100 rises rapidly from room temperature to the nozzle forming temperature setting unit 110 at the start of temperature rise control of the nozzle 100. After reaching the nozzle molding temperature setting unit 110, the temperature rises above the set temperature and gradually drops to cause the overshoot area 300 falling to the set temperature area, which causes overheating. In addition, when the material is a crystalline resin, the dissolved state of the material present in the nozzle 100 varies depending on the difference in heating delay time after reaching the set temperature. If the temperature rise of the heating cylinder 200 is too late, the nozzle 100 is already affected by the heat conducted from the heating cylinder 200 before the temperature rise control starts. Due to the temperature difference between the material present at the end of the nozzle 100 and the material present in front of the heating cylinder 200 close to the nozzle 100, there is a problem that a change in viscosity of the dissolved material occurs.

The present invention provides a preliminary heating step of controlling the nozzle heating temperature of the injection molding machine to a temperature range of the preliminary temperature setting unit in view of the above-described problems in the prior art, and the heating temperature of the heating cylinder reaches the temperature range of the preliminary temperature setting unit. If the heating temperature of the nozzle reaches the temperature range of the nozzle shaping temperature setting part, the heating time of the heating cylinder reaches the temperature range of the cylinder temperature setting part at the same time. By controlling the temperature in two stages of the heating step, it is possible to prevent overheating or deterioration of the materials present in the nozzle and to prevent gas generation and discoloration. It is invented for the purpose of being able to mold.

The present invention as a means for achieving the above object,

In order to heat and dissolve the material present in the heating cylinder and nozzle of the injection molding machine, the cylinder heating heater and the nozzle heating heater mounted on each of the heating cylinder and the nozzle are operated to set the heating cylinder and the nozzle, respectively, to the set final control target temperature. In the method of raising the temperature so as to heat up to,

The cylinder heating heater and the nozzle heating heater are simultaneously operated to simultaneously heat each of the heating cylinder and the nozzle to simultaneously increase the temperature, but the heating temperature of the nozzle heated faster than the heating cylinder is the final control target of the nozzle molding temperature setting unit. When the temperature range of the preliminary temperature setter set in advance to a temperature range lower than the temperature is reached, the nozzle heating heater is controlled until the heating temperature of the heating cylinder reaches the preliminary temperature setter to control the heating temperature of the nozzle. A preheating step of maintaining the same temperature range as the preliminary temperature setting unit;

Heated by the cylinder heating heater that is heated from the start of the pre-heating step, the nozzle heating heater to be heated again from the time the heating temperature of the heating cylinder is heated to a temperature higher than the temperature range of the preliminary temperature setting unit Each of the cylinder heating nozzle and the nozzle heating heater heats the heating cylinder and the nozzle at the same time, so that the temperature rises to the temperature range of the cylinder temperature setting unit and the nozzle forming temperature setting unit, which are the final control target temperatures of the heating cylinder and the nozzle, respectively. It is characterized in that it is configured to control the heating operation to increase the temperature to the nozzle forming temperature which is the final control target temperature of the nozzle by forming a set temperature heating step to be made in such a time zone.

In addition, the temperature range of the preliminary temperature setting unit is characterized in that the temperature range of 100 ~ 180 ℃ lower than the cylinder forming unit of the heating cylinder and the nozzle molding temperature setting unit which is the final control target temperature of the nozzle.

According to the present invention, in the preheating step, after heating the material present in the nozzle to the temperature range of the preliminary temperature setting part, the nozzle heating heater is controlled to maintain the heating temperature of the nozzle within the temperature range of the preliminary temperature setting part. After that, when the heating temperature of the heating cylinder reaches the preliminary temperature setting unit, the nozzle heating heater is operated again to reheat the nozzle, and the time zone during which the set temperature heating step starts from the preheating step is started. Since the temperature rises together with the heating cylinder and the nozzle being heated at the same time, the heating cylinder and the nozzle each reach the simultaneous cylinder temperature setting part and the nozzle molding temperature setting part at the same time, thereby overheating the material existing in the nozzle. To prevent deterioration as well as to material carbonization In addition, the heating temperature of the nozzle is first controlled in the temperature range of the preliminary temperature setting part in the preliminary heating step, and then heated again in the set temperature heating step so that the temperature rises, the nozzle temperature rise is the final control target temperature. It provides the effect that the overshoot phenomenon does not occur when the molding temperature setting portion is reached.

Detailed description of the two-stage temperature increase control method for an injection molding machine nozzle according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of an installation state of a heating cylinder and a nozzle of an injection molding machine for explaining the present invention, and FIG. 2 is a temperature display panel displaying measurement temperatures and preliminary temperature setting units of respective sections of the heating cylinder and the nozzle of the present invention. Figure 3 is a graph showing a control method for the temperature rise of the heating cylinder and the nozzle of the present invention.

1 shows a part (front part) of the heating cylinder 1 of the injection molding machine, and the heating cylinder 1 has a screw 2 for rotatable feeding and conveying the material (resin). It is provided, and a nozzle 3 for injecting the molten material into the mold is mounted at the front of the heating cylinder 1.

A cylinder heating heater 4 is installed on the outer circumference of the heating cylinder 1 to heat and dissolve the material present therein, and also on the outer circumference of the tip of the heating cylinder 1 and each of the nozzles 3. The nozzle heating heater 5 which heat-dissolves the material in the inside is provided.

The heating cylinder 1 is equipped with a cylinder temperature sensor 6 for measuring the heating temperature of the heating cylinder 1 heated by the heating operation of the heater 4 for cylinder heating, and the nozzle 3 The nozzle temperature sensor 7 for measuring the heating temperature of the nozzle 1 heated by the above-mentioned nozzle heating heater 5 is also attached to the outer periphery.

2 of the figure shows a temperature display panel 8 which displays a target temperature and a heating temperature of each of the heating cylinder 1 and the nozzle 3, wherein the temperature display panel 8 is an injection molding machine. It is mounted on the control unit that controls each device.

The temperature display panel 8 has a cylinder front temperature display portion 81a which shows the heating temperature measured by the cylinder temperature sensor 6 mounted at the front of the heating cylinder 1 as a digital signal, and although not shown in the drawing, heating Nozzle temperature sensor for measuring the heating temperature of the nozzle 3 and the cylinder middle part temperature display part 81b and the cylinder rear part temperature display part 81c which represent the temperature measured from the temperature sensor mounted in each of the middle part and the rear part of the cylinder. The preliminary temperature display section 83, which represents the temperature range of the preliminary preliminary temperature setting section 30 and the nozzle temperature display section 82, which numerically represents the heating temperature measured by (7), is formed.

3 shows a graph of a method of controlling the temperature rise of the heating cylinder 1 and the nozzle 3, wherein the cylinder temperature setting, which is the final control target temperature of the material existing in front of the heating cylinder 1, is set. The preliminary temperature setting unit 31 is set to a temperature range lower than the temperature range of the nozzle molding temperature setting unit 30 which is the final control target temperature for the material existing in the unit 10 and the nozzle 3, and the heating is performed. The time period from when the cylinder 1 starts heating operation to reach the temperature range of the preliminary temperature setting section 31 is set as the preheating step A, and the final control target at the front of the heating cylinder 1 is also set. The time period until reaching the cylinder temperature setting unit 10, which is the temperature, and the nozzle molding temperature setting unit 30, which is the final control target temperature of the nozzle 3, was set in the set temperature heating step (B).

As described above, the preliminary heating step (A) is set for the preliminary temperature setting unit 31, and the set temperature heating step (B) is set for the cylinder temperature setting unit 10 and the nozzle molding temperature setting unit 30, respectively. Step-wise control of the temperature rise of the cylinder 1 and the nozzle 3 is demonstrated.

First, the cylinder heating heater 4 and the nozzle heating heater 5 installed in each of the heating cylinder 1 and the nozzle 3 are simultaneously operated to heat the heating cylinder 1 and the nozzle 3 at the same time. In the time zone of the preheating step (A), the heating temperature of the nozzle 3 reaches the preliminary temperature setting unit 31 at a time earlier than the heating cylinder 1 as shown by the solid line in FIG. 3, and the heating cylinder The heating temperature of (1) reaches a time slower than the heating time of the nozzle 3 as shown by the dotted line in Fig. 3, wherein the heating temperature of the nozzle 3 is set to the preliminary temperature in the time zone of the preheating step (A). The nozzle heating heater 5 is controlled from the time point when the unit 31 is reached to control the heating temperature of the nozzle 3 to be maintained in the same temperature range as the preliminary temperature setting unit 31. Thus, the nozzle 3 Heating temperature control operation of the heating cylinder (1) to the preliminary temperature setting section (31). Continue until you reach is.

Next, when the heating temperature of the heating cylinder 1 reaches the preliminary temperature setting unit 31 and the temperature is continuously increased to enter the set temperature heating step (B), the nozzle installed in the nozzle (3) The heating heater 5 is restarted to heat the nozzle 3 again, and thus, the cylinder heating heater 4 and the nozzle heating heater 5 from the time period when the set temperature heating step (B) starts. Is heated together to heat the heating cylinder (1) and the nozzle (3) at the same time, from this time until the nozzle (3) reaches the temperature range of the nozzle shaping temperature setting unit 30 which is the final control target temperature The temperature rise of the heating temperature is achieved because the heating operation of the nozzle heating heater 7 is controlled in accordance with the measured temperature calculated by the following formula, whereby the heating temperature of the heating cylinder 1 is the final control target. In the cylinder temperature setting section 10 which is a temperature The time zone to be reached and the time zone in which the nozzle 3 is heated to the temperature range of the nozzle molding temperature setting unit 30 which is the final control target temperature are simultaneously made at the time when the cylinder temperature heating step B is completed.

<Official>

Nozzle Heating Temperature = (Set Temperature of Nozzle Molding Temperature Setting Part × Temperature Measured by Cylinder Temperature Sensor) ÷ Cylinder Temperature Setting Part

Since the heating temperature of the nozzle 3 calculated by the above formula increases as the heating temperature of the heating cylinder 1 increases gradually, the heating cylinder reaches the point where the set temperature heating step B is completed. 1) and the nozzles 3 are the same time zones at which the respective temperature ranges of the cylinder temperature setting unit 10 and the nozzle molding temperature setting unit 30 which are the final control target temperatures are reached.

The present invention configured as described above heats and dissolves the materials present in each of the heating cylinder 1 and the nozzle 3 of the injection molding machine. At the same time, the cylinder heating heater 4 and the nozzle heating heater 5 are simultaneously In operation, heating the heating cylinder 1 and the nozzle 3 at the same time, the heating cylinder 1 is a cylinder heating heater until it reaches the temperature range of the cylinder temperature setting section 10 which is the final control target temperature ( 4) continues to be operated, and in the case of the nozzle 3, when the heating temperature heated by the operation of the nozzle heating heater 5 reaches the preliminary temperature setting unit 31 in the preheating step (A). The nozzle heating heater (5) is primarily controlled to maintain the heating temperature of the nozzle (3) in the temperature range of the preliminary temperature setting unit (31), and the nozzle heating heater in the set temperature heating step (B) thereafter. (5) again, wherein the nozzle heating heater (5) The thermal operation is controlled in accordance with the heating temperature calculated by the above formula so that the heating temperature of the nozzle 3 rises to the temperature range of the nozzle forming temperature setting unit 30 which is the final control target temperature. And the time zone in which the heating temperature of the heating cylinder 1 reaches the temperature range of the cylinder temperature setting unit 10 which is the final control target temperature become equal. Accordingly, the material present in the nozzle 3 is the nozzle forming temperature. The heating temperature of the heating cylinder 1 heated to the temperature of the cylinder temperature setting unit 10 higher than the setting unit 30 is not affected by the overheating or deterioration.

<Examples>

As shown in FIG. 2, the temperature range of the cylinder temperature setting unit 10 which is the final control target temperature of the temperature of the cylinder front temperature display portion 81a of the heating cylinder 1 is 255 ° C., and the final control target temperature of the nozzle 3. Completion from the time when the set temperature heating step (B) starts based on the time when the temperature range of the phosphor nozzle molding temperature setting unit 30 is set to 250 ° C and 105 ° C of the preliminary temperature setting unit 31, respectively. The heating temperature of the nozzle 3 measured from the nozzle temperature sensor 7 with respect to the heating temperature of the heating cylinder 1 measured by the cylinder temperature sensor 6 until the 1> and, accordingly, by controlling the nozzle heating heater 5 to control the heating temperature of the nozzle 3 as shown in Table 1.

TABLE 1

Heating temperature (℃) of heating cylinder measured by cylinder temperature sensor           Heating temperature of nozzle (℃)                                  130.0                                  127.5                                  140.0                                  137.3                                  150.0                                  147.1                                  160.0                                  156.9                                  170.0                                  166.7                                  180.0                                  176.5                                  190.0                                  186.3                                  200.0                                  196.1                                  210.0                                  205.9                                  220.0                                  215.7                                  230.0                                  225.5                                  240.0                                  235.3                                  250.0                                  245.1                                  255.0                                  250.0

In Table 1, as the heating temperature of the heating cylinder 1 gradually rises, the heating temperature of the nozzle 3 is also controlled to increase relatively.

The heating temperature calculation method of the nozzle 3 is as follows.

① When the heating temperature of the heating cylinder 1 is 130.0 ° C, the heating temperature of the nozzle 3 is

     (250 × 130) ÷ 255 = 127.5 ℃

② When the heating temperature of the heating cylinder 1 is 180.0 ° C, the heating temperature of the nozzle 3 is

     (250 × 180) ÷ 255 = 176.5 ℃

③ When the heating temperature of the heating cylinder 1 is 230.0 ° C., the heating temperature of the nozzle 3 is

     (250 × 230) ÷ 255 = 225.5 ℃

1 is a cross-sectional view of an installation state of a heating cylinder and a nozzle of an injection molding machine for explaining the present invention.

2 is a view showing a target temperature and a heating temperature display device of each of the heating cylinder and the nozzle of the present invention.

Figure 3 is a graph of the temperature rise control method of the heating cylinder and the nozzle of the present invention.

4 and 5 are graphs of the temperature rise control method of the heating cylinder and the nozzle of the prior art.

[Description of Drawings]

1: heating cylinder 2: screw

3: nozzle 4: cylinder heating heater

5: Nozzle heating heater 6: Cylinder temperature sensor

7: Nozzle temperature sensor 8: Target temperature and heating temperature display device

81: Cylinder temperature display section 81a, 81b, 81c: Temperature setting section

82: nozzle temperature display unit 83: preliminary temperature display unit

10: cylinder temperature setting unit 30: nozzle molding temperature setting unit

31: preliminary temperature setting unit

A: Preheating stage B: Set temperature heating stage

Claims (2)

In order to heat and dissolve the material present in the heating cylinder and nozzle of the injection molding machine, the cylinder heating heater and the nozzle heating heater mounted on each of the heating cylinder and the nozzle are operated to set the heating cylinder and the nozzle, respectively, to the set final control target temperature. In the method of raising the temperature so as to heat up to, The cylinder heating heater and the nozzle heating heater are simultaneously operated to simultaneously heat each of the heating cylinder and the nozzle to simultaneously increase the temperature, but the heating temperature of the nozzle heated faster than the heating cylinder is the final control target temperature of the nozzle forming temperature setting unit. When the temperature range of the preliminary temperature setting section set in advance to the lower temperature range is reached, the nozzle heating heater is controlled until the heating temperature of the heating cylinder reaches the preliminary temperature setting section to reserve the heating temperature of the nozzle. A preheating step of maintaining the same temperature range as the temperature setting unit; From the start of the pre-heating step is heated by a cylinder heating heater that is heated to operate the nozzle heating heater again the heating operation from the time when the heating temperature of the heating cylinder is heated to a temperature higher than the temperature range of the preliminary temperature setting unit In the heating operation of the nozzle heating heater, the heating operation is controlled by the following <formula> and the above-mentioned cylinder heating heater and nozzle heating heater respectively heat the heating cylinder and the nozzle, so that the heating cylinder and the nozzle A set temperature heating step in which the temperature rises to the temperature range of each of the final control target temperatures of the cylinder temperature setting unit and the nozzle forming temperature setting unit at the same time period; and forms a temperature rise to the nozzle forming temperature which is the final control target temperature of the nozzle. Characterized in that it is configured to control the heating operation to It is a two-stage temperature increase control method for an injection molding machine nozzle. <Official> Nozzle Heating Temperature = (Set Temperature of Nozzle Molding Temperature Setting Part × Temperature Measured by Cylinder Temperature Sensor) ÷ Cylinder Temperature Setting Part The method of claim 1, The temperature range of the preliminary temperature setting part is a temperature range of 100 to 180 ° C. lower than the cylinder molding part of the heating cylinder and the nozzle molding temperature setting part which is the final control target temperature of the nozzle. Control method.

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