JP6955375B2 - Injection molding machine - Google Patents

Description

The present invention relates to an injection molding machine provided with a blower device for cooling a heating cylinder and injecting a resin melted by the heating cylinder into a cavity of a closed mold to manufacture a molded product, particularly in the heating cylinder. The present invention relates to an injection molding machine provided with a blower device capable of adjusting the temperature of the heat-melted resin so as to have an appropriate temperature.

In an injection molding machine that molds a molded product by injection molding, if the resin injected and filled in the cavity of the mold is higher than the appropriate predetermined temperature or if there is variation, the manufactured molded product may be discolored or discolored. Deterioration will occur. For this reason, the temperature of the resin that is heated and melted in the heating cylinder is required to be adjusted to an appropriate temperature. Therefore, a blower device having a blowing function is used to send cold air to a heater that can be a heat source of the heating cylinder, and the temperature is controlled so that the heating cylinder does not become hotter than necessary. As related to such a technique, for example, in Patent Documents 1 and 2, a plurality of heating parts including band heaters are provided in the axial direction of the heating cylinder, and air is sent to these plurality of heating parts from the cooling part to heat the heat. A technique for controlling the temperature of the resin supplied into the cylinder to be appropriate is disclosed.

Japanese Unexamined Patent Publication No. 2016-144924 Japanese Unexamined Patent Publication No. 2016-144925

In Patent Documents 1 and 2, it seems that the temperature of the heating cylinder (heating cylinder) can be adjusted so as not to be higher than necessary. However, the conventional cooling control technology for the heating cylinder is as follows. There is such a problem.

Depending on the type of pellets used as the raw material, the heating cylinder during heating may generate high shear insulation during the execution of the weighing process, and this high shear insulation causes the temperature of the heating cylinder to rise relatively rapidly, which is more than necessary. It may get hot. Then, when the temperature of the heating cylinder becomes higher than necessary, air is forcibly blown from a cooling means such as a blower device to lower the temperature of the heating cylinder to a predetermined temperature. However, when the temperature drops sharply due to the air blown to the heating cylinder, the heating heater operates based on the temperature drop, and the operations of the heater having a heating function and the cooling means such as a blower device having a cooling function strongly antagonize each other. There was a problem that they worked at the same time in this way, leading to a large amount of power consumption.

The present invention has been made in view of the above problems, and by paying attention to the energization rate of the energization type heater that heats the heating cylinder, and based on the energization rate, the amount of air blown to the heating cylinder is adjusted to control the temperature. An object of the present invention is to provide an injection molding machine capable of suppressing wasteful power consumption and adjusting the temperature of the resin in the heating cylinder to the optimum temperature.

The invention relating to this injection molding machine is
A heating cylinder to which a resin material that can be a molded product is supplied,
An energizing heater mounted on the outer periphery of the heating cylinder and heating and melting the resin material supplied into the heating cylinder.
An energization amount control means for controlling the energization amount to the energization type heater, and
An injection nozzle mounted on the tip of the heating cylinder and ejecting the resin material heated and melted in the heating cylinder into the cavity of the mold.
A heater cover surrounding the heating cylinder and
A blower device that blows air into the space between the heating cylinder and the heater cover,
An injection molding machine provided with a drive control means for controlling the drive of the blower device.
An opening / closing device that adjusts the amount of air blown from the blower device to the space between the heating cylinder and the heater cover.
A switchgear control means for controlling the switchgear operation of the switchgear is provided.
The energization amount control means changes the energization rate of the energization type heater so that the temperature of the resin material falls within a normal range.
Said switching control means such that said duty ratio of the energization heater is within a predetermined range set in advance in correspondence with the normal range, feeding of the line had before Symbol blower apparatus with a variable opening and closing operations of the opening and closing device and wherein the benzalkonium adjust the air volume.

Further, the invention relating to this injection molding machine is described.
Assuming that the lower limit of the energization rate in the predetermined range is the lower limit control value, when the lower limit control value is exceeded,
The switchgear control means fully opens the switchgear, the drive control means turns on the blower device, and the energization amount control means turns off the energization of the energization type heater.

Further, the invention relating to this injection molding machine is described.
Assuming that the upper limit of the energization rate in the predetermined range is the upper limit control value, when the upper limit control value is exceeded,
The drive control means turns off the blower device, and the energization amount control means turns on energization of the energization type heater.

Further, the invention relating to this injection molding machine is described.
A plurality of the energizing heaters are mounted on the outer circumference of the heating cylinder.
The blower device is provided corresponding to these energized heaters.
The switchgear control means variably opens and closes each switchgear so that the energization rates for all the energizing heaters provided corresponding to each of the blower devices fall within a predetermined range, and adjusts the temperature of the heating cylinder. It is characterized by performing.

Further, the invention relating to this injection molding machine is described.
The lower limit control value of the energization rate of the energization type heater is 5%, and the upper limit control value is 10%.

Further, the invention relating to this injection molding machine is described.
The opening / closing device is characterized in that it opens / closes an air suction port or an air discharge port provided in the blower device.

In the present invention, the energization rate is the ratio of energization to the energization type heater as described below, and can be obtained from the time when the heater is energized during the control cycle of the heater. For example, if the heater control cycle is 5 seconds and the heater is energized for 1 second, the energization rate will be 20%.

According to the present invention, the temperature adjustment control is performed by adjusting the amount of air blown to the heating cylinder based on the preset energization rate of the energization type heater that heats the heating cylinder. It is possible to suppress the occurrence of wasteful power consumption due to the operations of the heater having the heater and the cooling means such as a blower device having a cooling function strongly competing with each other and working at the same time, and in the heating cylinder. The temperature of the resin can be adjusted to the optimum temperature.

As described above, according to the present invention, when the temperature of the heating cylinder rises above a predetermined temperature due to the shear insulation of the resin accompanying the weighing process and the energization rate of the energization type heater falls below the lower limit control value (5%). , Heating by the energizing heater is stopped (energization off), the opening and closing device is fully open, and the heating cylinder is cooled and the temperature is adjusted by blowing air (on) from the blower device, so the heating means (energization type heater) It is possible to suppress a large amount of power consumption due to the antagonistic operation between the heat and the cooling means (blower device), and it is possible to adjust the temperature so that the temperature of the resin in the heating cylinder becomes a predetermined temperature.

Further, according to the present invention, when the temperature of the heating cylinder falls below a predetermined temperature and the energization rate of the energization type heater exceeds the upper limit control value (10%), the energization type heater is in the heating (energization on) state. , The air blown from the blower device is stopped (off). As a result, the temperature of the resin is adjusted by the heating cylinder without operating the blower device, so that the power consumption associated with the operation of the energized heater can be suppressed and the temperature of the resin in the heating cylinder becomes a predetermined temperature. The temperature can be adjusted so as to be.

As an embodiment of the present invention, it is a block diagram which shows the injection unit configured in the injection molding machine, and shows the state which the opening / closing device is removed. As an example of the present invention, it is the schematic explanatory drawing which shows typically the injection unit configured in the injection molding machine. As an embodiment of the present invention, it is the schematic which shows the state which opened the opening / closing device fully open and opened the suction port of a blower device. As an embodiment of the present invention, it is the schematic which shows the state which the opening and closing device is fully closed and the suction port of a blower device is closed.

Hereinafter, examples of the embodiment of the present invention will be described with reference to FIGS. 1 to 4. Of course, the present invention is not limited to the specific embodiments described in the present embodiment as long as it does not contradict the gist of the invention, and can be easily changed by those skilled in the art. Needless to say, it is easily applicable.

1 and 2 show an injection unit 1 configured in the injection molding machine of the present embodiment. The injection unit 1 is provided with a tubular heating cylinder 2 to which a resin material as a raw material of a molded body is supplied, and a screw 3 which is rotatably provided in the heating cylinder 2 and is operated when performing a weighing process. An energization type heater 4 mounted on the outer periphery of the heating cylinder 2 and heating and melting the resin material supplied into the heating cylinder 2, an energization amount control means 5 for controlling the energization amount to the energization type heater 4, and a heating cylinder 2. An injection nozzle 6 mounted on the tip and ejecting the resin material melted in the heating cylinder 2 into the cavity of the mold, a heater cover 7 surrounding the outside of the heating cylinder 2, and a heating cylinder provided on the upper part of the heater cover 7. Blower device 8 that adjusts the temperature of the heating cylinder 2 by blowing air into the space S formed between 2 and the heater cover 7, drive control means 9 that controls the drive of the blower device 8, and the entire injection unit. The control means 10 and the like for controlling various operations of the above are provided.

As shown in FIGS. 1 to 2, a plurality of energized heaters 4 of this embodiment are provided, and the first energized heater 4A and the second energized heater 4B are provided from the front to the rear of the injection unit 1. It is composed of four energizing heaters, a third energizing heater 4C and a fourth energizing heater 4D. In this embodiment, the first to third blower devices 8A to 8C are provided corresponding to each of the first to third energizing heaters 4A to 4C except for the fourth energizing heater 4D. There is. A fourth blower device corresponding to the fourth energization type heater 4D may be provided.

Each of the blower devices 8 (first to third blower devices 8A to 8C) has an air suction port 11 that takes in air from the outside, and an air intake port 11 that takes in air from the air suction port 11 to a heating cylinder 2 and a heater cover 7. An air discharge port 12 for discharging air to the space S between the spaces is provided. Further, as shown in FIG. 1, a partition rib 13 for rectifying the air discharged from each air discharge port 12 is provided between the first to third blower devices 8A to 8C.

As shown in FIGS. 3 to 4, the injection unit 1 is provided with an opening / closing device 14 for opening / closing the air suction port of the blower device 8. The switchgear 14 opens and closes the air suction port 11 by the air volume adjusting valve 15 by operating the air volume adjusting valve 15 for opening and closing the air suction port 11, the air cylinder 16 for sliding the air volume adjusting valve 15, and the air cylinder 16. An opening / closing control means 17 for controlling is provided.

Here, the temperature adjustment control of the resin of the present invention will be described below based on Table 1 below. Here, in order to simplify the control, the energization rate A of the energization type heater is lower than the lower limit control value (in the case of a in Table 1), and the energization rate A of the energization type heater is higher than the upper limit control value. In the case (in the case of c in Table 1), the blower control is on / off control and the air volume control is fully open / closed control, but all may be variable control by an inverter or the like.

When the injection molding machine is operated, as shown in column 1b of Table, the air volume adjusting valve 15 is fully opened or the opening degree is variable, the operation of the energized heater 4 is variablely controlled, and the blower device 8 is on / off or variable controlled. By doing so, the energization rate of each energization type heater 4 controlled by the energization amount control means 5 changes in the range of 5% to 10%, and the resin temperature is maintained normally.

Then, when the temperature of the resin becomes high (exceeding the upper limit value of the normal range) due to shear insulation or the like accompanying the weighing process, the control means 10 controls the energization amount control means 5 to lower the temperature of the resin and lowers the energization rate. Then, as shown in the column 1a of Table 1, when the energization rate of each energization type heater 4 falls below 5%, each energization type heater 4 is turned off, and each blower device 8 is in a state where each air volume adjusting valve 15 is fully opened. Is turned on, which cools the resin in the heating cylinder 2 so that the temperature is within the normal range.

On the other hand, when the temperature of the resin becomes low (below the lower limit of the normal range), the control means 10 controls the energization amount control means 5 to raise the energization rate in order to raise the temperature of the resin, and the energization rate is increased. As shown, when the energization rate of each energizing heater 4 exceeds 10%, each energizing heater 4 is turned on (maintained on), and each air volume adjusting valve 15 is fully closed or fully opened. The blower device 8 is turned off, whereby the temperature of the resin in the heating cylinder 2 is heated to be within the normal range.

As described above, according to the injection molding machine of the present embodiment, the temperature adjustment control is performed by adjusting the amount of air blown to the heating cylinder 2 based on the energization rate of the energizing heater 4 that heats the heating cylinder 2. As in the past, the operations of a heater having a heating function and a cooling means such as a blower device having a cooling function work at the same time so as to strongly antagonize each other, resulting in a large amount of wasteful power consumption. And the temperature of the resin in the heating cylinder can be adjusted to the optimum temperature.

Further, when the temperature of the heating cylinder 2 rises above a predetermined temperature due to the shear insulation of the resin accompanying the weighing process and the energization rate of the energization type heater 4 falls below the lower limit control value (5%), the energization type heater 4 is used. With the heating stopped (energized off) and the opening / closing device 14 fully open, the heating cylinder 2 is cooled and the temperature is adjusted by blowing air (on) from the blower device 8, so that the heating means (energized heater) and cooling are performed. It is possible to suppress a large amount of power consumption due to an antagonistic operation with the means (blower device), and it is possible to adjust the temperature so that the temperature of the resin in the heating cylinder becomes a predetermined temperature.

Further, according to the present invention, when the temperature of the heating cylinder 2 falls below a predetermined temperature and the energization rate of the energizing heater 4 exceeds the upper limit control value (10%), the energizing heater 4 is heated (energized on). In this state, the air blown from the blower device 8 is stopped (off). As a result, the temperature of the resin is adjusted by the heating cylinder 2 without operating the blower device 8, so that the power consumption associated with the operation of the energized heater 4 can be suppressed and the temperature of the resin in the heating cylinder 2 can be suppressed. The temperature can be adjusted so that

Although an example of the present embodiment has been described in detail above, the present invention is not limited to the above-mentioned embodiment, and various modifications can be carried out within the scope of the gist of the present invention. In the above example, the air volume adjusting valve 15 of the switchgear 14 opens and closes the air suction port 11 provided in the blower device 8 to adjust the air volume, but instead of the air suction port 11 of the blower device 8, The air volume may be adjusted by opening and closing the air outlet 12 of the blower device 8, or a variable control means such as an inverter that changes the opening / closing amount (that is, the air volume) may be used. Just do it.

1 Injection unit 2 Heating cylinder 3 Screw 4 Energizing heater 4A 1st energizing heater 4B 2nd energizing heater 4C 3rd energizing heater 4D 4th energizing heater 5 Energizing amount control means 6 Injection nozzle 7 heater Cover 8 Blower device 8A 1st blower device 8B 2nd blower device 8C 3rd blower device 9 Drive control means 10 Control means 11 Air intake port 12 Air outlet 13 Partition rib 14 Switchgear 15 Air volume control valve 16 Air cylinder 17 Open / close control means S space

Claims (6)

A heating cylinder to which a resin material that can be a molded product is supplied,
An energizing heater mounted on the outer periphery of the heating cylinder and heating and melting the resin material supplied into the heating cylinder.
An energization amount control means for controlling the energization amount to the energization type heater, and
An injection nozzle mounted on the tip of the heating cylinder and ejecting the resin material heated and melted in the heating cylinder into the cavity of the mold.
A heater cover surrounding the heating cylinder and
A blower device that blows air into the space between the heating cylinder and the heater cover,
An injection molding machine provided with a drive control means for controlling the drive of the blower device.
An opening / closing device that adjusts the amount of air blown from the blower device to the space between the heating cylinder and the heater cover.
A switchgear control means for controlling the switchgear operation of the switchgear is provided.
The energization amount control means changes the energization rate of the energization type heater so that the temperature of the resin material falls within a normal range.
Said switching control means such that said duty ratio of the energization heater is within a predetermined range set in advance in correspondence with the normal range, feeding of the line had before Symbol blower apparatus with a variable opening and closing operations of the opening and closing device injection molding machine, wherein the benzalkonium adjust the air volume. Assuming that the lower limit of the energization rate in the predetermined range is the lower limit control value, when the lower limit control value is exceeded,
The first aspect of the present invention is characterized in that the switchgear control means fully opens the switchgear, the drive control means turns on the blower device, and the energization amount control means turns off the energization of the energization type heater. The injection molding machine described. Assuming that the upper limit of the energization rate in the predetermined range is the upper limit control value, when the upper limit control value is exceeded,
The injection molding machine according to claim 2, wherein the drive control means turns off the blower device, and the energization amount control means turns on energization of the energization type heater. A plurality of the energizing heaters are mounted on the outer circumference of the heating cylinder.
The blower device is provided corresponding to these energized heaters.
The opening / closing control means variably opens / closes each opening / closing device and adjusts the temperature of the heating cylinder so that the energization rates for all the energizing heaters provided corresponding to each of the blower devices fall within a predetermined range. The injection molding machine according to claim 3, wherein the injection molding machine is characterized in that. The injection molding machine according to any one of claims 1 to 4 , wherein the lower limit control value of the energization rate of the energization type heater is 5%, and the upper limit control value is 10%. The injection molding machine according to claim 5, wherein the opening / closing device opens / closes an air suction port or an air discharge port provided in the blower device.

Images