JP2003039158A - Metal injection molding method - Google Patents

Abstract

(57) [PROBLEMS] In a metal injection molding method performed using a hot runner type metal molding die apparatus, a heating and cooling process of a nozzle portion 13 in a hot runner is optimized and a molding cycle is required. Provide a way to minimize time. Kind Code: A1 A method of performing metal injection molding using a hot runner type metal molding die apparatus, wherein in one injection molding cycle, nozzle temperature is controlled using three-stage set temperatures. . The three set temperatures are a steady (stop) set temperature, an injection start set temperature, and a post-injection set temperature in the order of progress of the injection molding cycle. It is preferable to set the steady (stop) set temperature higher than the set temperature after the injection is completed, and to set the injection start set temperature higher than the steady (stop) set temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for injection molding a metal forming material, particularly a light metal alloy material such as a magnesium alloy and an aluminum alloy, using a metal forming die device having a hot runner in the die. . In particular, the present invention relates to a molding method in which the temperature control of a mold is optimized.

[0002]

2. Description of the Related Art FIG. 1 is a diagram schematically showing a vertical cross section of a general metal molding die apparatus having a hot runner in a die among apparatuses used in a metal injection molding method.

Generally, in a hot runner type mold,
The light metal alloy material, which is the metal molding material S melted in the molding machine cylinder (not shown), is runner 11 in the mold heated from the nozzle 10 of the molding machine to a temperature at which it does not solidify in the mold. After passing through the sub-runner 12, the metal molding material S is injected from the nozzle 13 into the mold product section 7 set to a temperature at which the metal molding material S is solidified, and a predetermined molded product is obtained.

The temperature of the nozzle portion 13 is higher than the temperature of the die product portion by the heating means (not shown) incorporated in the nozzle portion 13 and lower than the temperature of the runner portion in the die. By controlling the temperature to a preset value as the process progresses, the metal molding material is prevented from flowing out to the product part of the mold before injection. Is heated to the temperature required to melt.

Further, one of the purposes of the hot runner type mold is to maintain the temperature of the metal molding material as high as possible as close to the product part as possible when molding is performed using the metal molding material having a short solidification time. Is to be used as a means. That is, since such a material has a short solidification time and the length that can flow from one gate to the product part is limited, it is a means to prevent solidification of the flow path of the material having a long and complicated shape and route. At the same time, it improves the material yield. Another object is to improve the material yield and thereby reduce the injection weight, thereby shortening the weighing time. In the case of a molded product having a large weight, the injection weight was further increased, and the measurement time was lengthened and the entire molding cycle was lengthened. By using a hot runner, the injection weight can be reduced and the metering time can be shortened, resulting in an attempt to shorten the entire molding cycle.

[0006]

However, in the above metal injection molding method, it is difficult to shorten the molding cycle as intended or to secure a predetermined number of cycles per unit time. It was accompanied by points.

In the molding method using the hot runner type mold, the conventional temperature control of the nozzle part 13 is higher than the temperature of the mold product part 7 as the process progresses, as shown in FIG. 5, for example. A steady set temperature that is a temperature that is lower than the runner portion (11, 12) temperature in the mold, and an injection start set temperature for the injection operation that performs injection molding from the injection molding machine. It was done using a set temperature of the stages.

Specifically, this process is carried out in the following cycle of steps. The temperature of the nozzle unit 13 at the time of starting the mold closing operation for closing the mold for injection molding, which is the start of one cycle, is a relatively low temperature of the two-stage set temperatures. It is at a certain steady (stop) set temperature. Upon receiving the mold closing start signal by the mold closing operation, the temperature rise of the nozzle portion 13 is started. After the temperature rise is started, when the nozzle temperature reaches the injection start set temperature, which is a relatively higher temperature of the two-stage set temperatures, the molding machine receives the temperature rise completion signal and completes the injection operation. Upon completion of the injection operation, in response to the injection completion signal, the nozzle temperature starts cooling toward the steady (stop) set temperature, while the molding machine side starts measuring the metal molding material in preparation for the next cycle. To do. After the injection is completed, the mold opening operation is started when the preset cooling time elapses, and when the steady (stop) set temperature is reached, the product is taken out, the mold release agent is applied to the mold, and then the next cycle is started. The mold closing operation of is started.

In this one cycle, the nozzle temperature actually continues to rise by a certain temperature even after the injection is completed, as shown by the chain double-dashed line in FIG. 5, and then cooling is started. Was. In addition, after the product is taken out, it is necessary to make the nozzle temperature reach the steady (stop) set temperature in preparation for the next cycle, so the nozzle is heated to raise the temperature. Was causing overshoot. For example, in the example shown in FIG. 5, overshoot occurs with an overshoot width of Δt5.

According to such a temperature control method, the time required to reach one set temperature (one cycle time) depending on the molding conditions and the surrounding environment is longer than the standard set predetermined time. Can be significantly longer. When such a cycle time varies, the time required for one cycle becomes irregular and the molding cycle cannot be shortened as intended, and a predetermined cycle per unit time There was a problem that the number of times could not be secured.

Further, in the case of temperature control using two-step set temperatures, overshoot may actually occur at each set temperature, but overshoot occurs at a steady (stop) set temperature on the relatively low temperature side. Causes the nozzle temperature to rise above the expected temperature,
Before starting the next cycle, problems such as leakage of the metal molding material from the nozzle portion 13 occurred. Especially Φ1
A mold for a relatively large molded product that requires a gate diameter of 0 or more has a nozzle portion 13 that is larger than a mold for a relatively small molded product.
The above-mentioned problems are likely to occur because it takes a long time to heat up and cool down. Therefore, in order to perform stable molding, it is necessary to set a large temperature rise range by lowering the temperature setting on the low temperature side. There has been a problem that it becomes more difficult to secure the number of cycles of.

The present invention solves the above problems,
In a metal injection molding method using a hot runner type metal mold apparatus, a nozzle unit 1 in a hot runner is used.
It is an object of the present invention to provide a method for optimizing the heating and cooling process of No. 3 to minimize the time required for the molding cycle.

[0013]

A metal injection molding method according to the present invention is a method of performing metal injection molding using a hot runner type metal molding die apparatus, and in one injection molding cycle. It is characterized in that the nozzle temperature is controlled using three set temperatures.

This metal injection molding method is characterized in that the three set temperatures are a steady (stop) set temperature, an injection start set temperature, and a post-injection set temperature in the order of progress of the injection molding cycle. it can.

In the present invention, the steady (stop) set temperature is a temperature set in the nozzle when the molding machine is stopped or in a steady state other than during the injection operation, and is at least the nozzle portion 1.
3 is a temperature at which the metal molding material does not drool, and the injection start set temperature is a temperature set in the nozzle when the metal molding material is injection molded from the injection molding machine, and at least the metal molding material is set in the mold. The temperature after injection is complete is the temperature that is set for the nozzle after the injection process is complete, and the nozzle temperature is steady (stops) for the next injection molding cycle. ) A temperature that is selected so that it can return to the set temperature as quickly as possible.

The steady (stop) set temperature, the injection start set temperature, and the set temperature after completion of injection are the combination of the injection molding machine and the metal injection metal molding material used, the size (cross-sectional area) of the nozzle portion, Particularly, the temperature is selected and determined according to the heat capacity of the nozzle portion.

In the above metal injection molding method, the steady (stop) set temperature is set higher than the set temperature after the injection is completed, and the injection start set temperature is set higher than the steady (stop) set temperature. It can be a feature.

The above metal injection molding method further starts the process of proceeding from the steady (stop) set temperature to the injection start set temperature based on the cycle completion signal from the molding machine,
Based on the injection completion signal from the molding machine, start the process of proceeding from the injection start set temperature to the set temperature after the injection is completed,
In addition, it is possible to perform one injection molding cycle operation by starting the process of proceeding from the set temperature after completion of injection to the steady (stop) set temperature based on the fact that the measured temperature has reached the set temperature after completion of injection. It can be a feature.

The above metal injection molding method further starts the process of proceeding from the steady (stop) set temperature to the injection start set temperature based on the cycle completion signal from the molding machine,
Based on the injection completion signal from the molding machine, start the process of proceeding from the injection start set temperature to the set temperature after the injection is completed,
In addition, one injection molding cycle is operated by starting a process from a set temperature after completion of injection to a steady (stop) set temperature based on the fact that a preset time has been reached after completion of injection. can do.

The above metal injection molding method further starts the process of proceeding from the steady (stop) set temperature to the injection start set temperature based on the cycle completion signal from the molding machine,
Based on the injection completion signal from the molding machine, start the process of proceeding from the injection start set temperature to the set temperature after the injection is completed,
And the time it takes for the measured temperature to reach the set temperature after completion of injection,
And by starting the process from the set temperature after the completion of injection to the steady (stop) set temperature based on the time whichever comes first, whichever comes first after the completion of injection, whichever comes first. It can be characterized by performing one injection molding cycle operation.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. INDUSTRIAL APPLICABILITY The present invention can apply a metal molding material to injection molding and can be applied to a metal molding die device having a hot runner in the die.

(Embodiment 1) FIG. 1 shows a cross-sectional view of a typical hot runner type mold device as such a mold device for metal forming, and the right side of the mold device outside the drawing. An injection molding machine is connected to. Reference numeral 10 denotes a nozzle of the injection molding machine, which is connected to the nozzle 10 of the injection molding machine by bringing the mold sprue 4 of the metal molding die device into contact with the nozzle 10 (see FIG. The molten metal molding material S extruded from (not shown) is sent to the runner 11 through the mold sprue 4.

Reference numeral 1 is a stationary mold device of the metal mold device, and the mold sprue 4, runner 11 and sub runner 12 are formed in the manifold block 3.
Since the manifold block 3 is equipped with a heating device (not shown), the metal molding material S sent to the runner 11
At least while maintaining the molten state, and further sub-runner 1
After reaching 2, the nozzle portion 13 is reached.

On the left side of the fixed mold device 1, a movable mold device 2 having a movable mold plate 5 and a movable spacer 6 is provided.
And the ejection pin 8 and the ejection plate 9 are disposed inside the movable mold device 2.

In a state where the movable side mold device 2 is in close contact with the fixed side mold device 1 (the mold is closed) and the metal molding material is not injected from the molding machine, the nozzle is The temperature of the portion 13 is set to a temperature at which the phenomenon that the metal molding material S flows out from the nozzle portion 13 into the mold product portion 7, that is, the so-called dripping phenomenon does not occur. In this state, the nozzle temperature is set to a temperature lower than the temperature at which the metal molding material S can be kept in a molten state. This state is called the steady state of the mold device, and the molding machine is stopped, so it is stopped. Also called a state. Therefore, the temperature at this time is referred to as a steady (stop) set temperature in the present invention.

The operation of one injection molding cycle when the injection molding process is repeated will be described with reference to FIG. 1 and FIG. 2 for explaining the steps of the injection molding process. When the nth injection molding cycle is performed, the mold closing operation for the nth injection molding cycle is started based on the cycle completion signal notifying that the n-1th injection molding cycle is completed. When the mold closing is completed, a mold closing completion signal is sent to the molding machine. Then, when the nozzle temperature reaches the injection start set temperature at which the metal molding material S can be kept in a molten state, a temperature increase completion signal is sent to the molding machine. Then, the molding machine injects the metal molding material, so that the metal molding material is introduced (injection molding) into the mold product unit 7. When the injection of the predetermined amount of metal molding material is completed, an injection completion signal is issued from the molding machine.

When cooling of the nozzle is started in response to the injection completion signal, the heat capacity of the entire manifold block 3 is relatively large, so the nozzle temperature once rises to a temperature slightly above the injection start set temperature and then begins to fall. . Although the drop of the nozzle temperature is performed with the target of the set temperature after the completion of injection, in the first embodiment of the present invention, the nozzle temperature is actually measured, and the fact that the actually measured temperature of the nozzle reaches the set temperature after the completion of injection is confirmed. Upon detection, the process proceeds from the set temperature to the steady (stop) set temperature after the completion of injection.

The set temperature after completion of injection is a little lower than the steady (stop) set temperature, and the metal molding material existing in the nozzle portion 13 is solidified, and the gate of the metal molding material can be cut off in the nozzle portion 13. And the nozzle part 1
3 is the temperature at which the metal molding material does not drip,
It is a temperature that can be determined in consideration of the metal molding material and the characteristics of the metal molding die device. After the injection is completed, by setting the set temperature to a temperature lower than the steady (stop) set temperature,
It is possible to increase the cooling rate, and it is possible to prevent the steady (stop) set temperature from greatly exceeding even if the temperature setting overshoots as the process progresses. Therefore, the steady (stop) set temperature can be set to the maximum temperature at which the metal molding material does not cause dripping from the nozzle portion 13.

As a result, the temperature difference between the steady (stop) set temperature and the injection start set temperature can be minimized, and the temperature rise time of the nozzle portion 13 can be shortened. Therefore, it is possible to shorten the entire molding cycle by minimizing the time required for one injection molding cycle through the temperature rising / cooling process of the nozzle portion 13.

In parallel with this process, the mold opening operation is started when a predetermined cooling set time has elapsed, and the product is taken out from the mold when the mold opening operation is completed. If necessary, a mold release agent is applied to the mold for the (n + 1) th injection molding cycle, and then the mold closing operation for the (n + 1) th injection molding cycle is started.

On the other hand, the nozzle is heated with a steady (stop) set temperature as a target, but it is actually difficult to directly reach the steady (stop) set temperature, and the extent of the heating. Due to this, the nozzle temperature may cause some overshoot. In the example shown in FIG.
After the injection is completed, the temperature reaches the set temperature through a variation that causes an overshoot with an overshoot width of Δt2. At this point, the cycle complete signal is issued.

As described above, the target temperature for cooling is not set to the steady (stop) set temperature, but set to the set temperature after injection completion, which is a temperature lower than the steady (stop) set temperature. After the nozzle temperature reaches the set point, the nozzle section 13 is moved to the steady (stop) set temperature.
The time required for the temperature rising / cooling process can be minimized, and the entire molding cycle can be shortened.

(Second Embodiment) Next, a metal injection molding method according to another embodiment of the present invention will be described with reference to FIGS. The metal injection molding method of the second embodiment is basically the same as the metal injection molding method described in the first embodiment, but the nozzle portion 13 is cooled unlike the method described in the first embodiment. Different conditions determine that the process is complete.

In the metal injection molding method of the second embodiment, when the nth injection molding cycle is performed, n-1
The mold closing operation for the n-th injection molding cycle is started based on the cycle completion signal indicating that the injection molding cycle for the second time has been completed. When the mold closing is completed, a mold closing completion signal is sent to the molding machine. Then, when the nozzle temperature reaches the injection start set temperature at which the metal molding material S can be kept in a molten state, a temperature increase completion signal is sent to the molding machine. Then, the molding machine injects the metal molding material, so that the metal molding material is introduced (injection molding) into the mold product unit 7. When the injection of the predetermined amount of metal molding material is completed, an injection completion signal is issued from the molding machine.

When cooling of the nozzle is started in response to the injection completion signal, since the heat capacity of the entire manifold block 3 is relatively large, the nozzle temperature once rises to a temperature slightly higher than the injection start set temperature and then begins to fall. . The lowering of the nozzle temperature is performed with the set temperature as a target after the completion of injection.

In the method of the second embodiment, a predetermined time is set in advance as the cooling set time, and the setting after the completion of injection is set from the cooling process (the process of proceeding from the injection start set temperature to the set temperature after the injection completion). From temperature to steady (stop)
This is different from the method of the first embodiment in that the condition for shifting to the process of advancing to the set temperature is the time when the cooling set time has elapsed after the start of the cooling process.

By presetting a time according to this cooling rate and controlling the temperature to a steady (stop) set temperature after the start of cooling after this time has elapsed, even if there is a difference in the cooling rate between shots, the molding cycle It is possible to perform molding in a constant molding cycle without extending the length. Further, by setting the set temperature low after the injection is completed, even if the overshoot with respect to the temperature setting occurs as the process progresses, it is possible to prevent the steady (stop) set temperature from being greatly exceeded, and the steady (stop) set temperature can be prevented. It is also possible to set the maximum temperature at which the metal molding material does not cause dripping from the nozzle portion 13. As a result, it is also possible to minimize the temperature difference between the steady (stop) set temperature and the injection start set temperature. Therefore, the temperature rise time of the nozzle part 13 can be shortened, and the time required for one injection molding cycle through the temperature rise / cooling process of the nozzle part 13 can be minimized to shorten the entire molding cycle. Became.

In parallel with this process, the mold opening operation is started when a predetermined cooling set time has elapsed, and the product is taken out of the mold when the mold opening operation is completed. If necessary, a mold release agent is applied to the mold for the (n + 1) th injection molding cycle, and then the mold closing operation for the (n + 1) th injection molding cycle is started.

On the other hand, the nozzle is heated with the steady (stop) set temperature as a target, but it is actually difficult to directly reach the nozzle temperature to the steady (stop) set temperature. Due to this, the nozzle temperature may cause some overshoot. In the example shown in FIG.
After the injection is completed, the set temperature is reached after a change that causes an overshoot with an overshoot width of Δt3. At this point, the cycle complete signal is issued.

As described above, the target temperature for cooling is not set to the steady (stop) set temperature, but set to the set temperature after injection completion, which is a temperature lower than the steady (stop) set temperature. After the nozzle temperature reaches the set point, the nozzle section 13 is moved to the steady (stop) set temperature.
The time required for the temperature rising / cooling process can be minimized, and the entire molding cycle can be shortened.

(Third Embodiment) Next, a metal injection molding method according to still another embodiment of the present invention will be described with reference to FIGS. The metal injection molding method of the third embodiment is basically the same as the metal injection molding method described in the first embodiment, but the nozzle portion 13 is cooled unlike the method described in the first embodiment. Different conditions determine that the process is complete.

In the metal injection molding method of the third embodiment, when the nth injection molding cycle is performed, n-1
The mold closing operation for the n-th injection molding cycle is started based on the cycle completion signal indicating that the injection molding cycle for the second time has been completed. When the mold closing is completed, a mold closing completion signal is sent to the molding machine. Then, when the nozzle temperature reaches the injection start set temperature at which the metal molding material S can be kept in a molten state, a temperature increase completion signal is sent to the molding machine. Then, the molding machine injects the metal molding material, so that the metal molding material is introduced (injection molding) into the mold product unit 7. When the injection of the predetermined amount of metal molding material is completed, an injection completion signal is issued from the molding machine.

When cooling of the nozzle is started in response to the injection completion signal, the heat capacity of the entire manifold block 3 is relatively large, so that the nozzle temperature once rises to a temperature slightly above the injection start set temperature and then begins to fall. . The lowering of the nozzle temperature is performed with the set temperature as a target after the completion of injection.

Also in the method of the third embodiment, the nozzle temperature is lowered with the target temperature set after the completion of injection. In the third embodiment, by actually measuring the nozzle temperature,
This is performed in parallel with setting a predetermined time as the cooling set time in advance. Then, the cooling process (injection start setting) is performed at a time point at which the measured value of the nozzle temperature reaches the set temperature after the completion of injection or the time point at which the preset cooling setting time elapses, whichever is earlier. The process of progressing from the temperature to the set temperature after completion of the injection) to the process of progressing from the set temperature to the steady (stop) set temperature after the completion of injection.

As a result, the temperature difference between the steady (stop) set temperature and the injection start set temperature can be minimized, and the temperature rising time of the nozzle portion 13 can be shortened. Therefore, it is possible to shorten the entire molding cycle by minimizing the time required for one injection molding cycle through the temperature rising / cooling process of the nozzle portion 13.

In parallel with this process, the mold opening operation is started when a predetermined cooling set time has elapsed, and when the mold opening operation is completed, the product is taken out from the mold. If necessary, a mold release agent is applied to the mold for the (n + 1) th injection molding cycle, and then the mold closing operation for the (n + 1) th injection molding cycle is started.

On the other hand, although the nozzle is heated with the steady (stop) set temperature as a target, it is actually difficult to directly reach the nozzle temperature to the steady (stop) set temperature. Due to this, the nozzle temperature may cause some overshoot. In the example shown in FIG.
After the completion of injection, the temperature reaches the set temperature through a variation that causes an overshoot with an overshoot width of Δt4. At this point, the cycle complete signal is issued.

As described above, the target temperature for cooling is not set to the steady (stop) set temperature, but set to the set temperature after completion of injection which is lower than the steady (stop) set temperature. After the nozzle temperature reaches the set point, the nozzle section 13 is moved to the steady (stop) set temperature.
The time required for the temperature rising / cooling process can be minimized, and the entire molding cycle can be shortened.

By presetting a time in accordance with this cooling rate, and after this time has elapsed, by controlling to a steady (stop) set temperature after starting cooling, even if there is a difference in cooling rate between shots, the molding cycle It is possible to perform molding in a constant molding cycle without extending the length. Further, by setting the set temperature low after the injection is completed, even if the overshoot with respect to the temperature setting occurs as the process progresses, it is possible to prevent the steady (stop) set temperature from being greatly exceeded, and the steady (stop) set temperature can be prevented. It is also possible to set the maximum temperature at which the metal molding material does not cause dripping from the nozzle portion 13. As a result, it is also possible to minimize the temperature difference between the steady (stop) set temperature and the injection start set temperature. Therefore, the temperature rise time of the nozzle part 13 can be shortened, and the time required for one injection molding cycle through the temperature rise / cooling process of the nozzle part 13 can be minimized to shorten the entire molding cycle. Became.

In parallel with this process, the mold opening operation is started when a predetermined cooling set time has elapsed, and when the mold opening operation is completed, the product is taken out from the mold. If necessary, a mold release agent is applied to the mold for the (n + 1) th injection molding cycle, and then the mold closing operation for the (n + 1) th injection molding cycle is started.

On the other hand, although the nozzle is heated with the steady (stop) set temperature as a target, it is actually difficult to directly reach the nozzle temperature to the steady (stop) set temperature. Due to this, the nozzle temperature may cause some overshoot. In the example shown in FIG.
After the injection is completed, the set temperature is reached after a change that causes an overshoot with an overshoot width of Δt3. At this point, the cycle complete signal is issued.

As described above, the target temperature for cooling is not set to the steady (stop) set temperature, but is set to the set temperature after injection completion, which is a temperature lower than the steady (stop) set temperature. After the nozzle temperature reaches the set point, the nozzle section 13 is moved to the steady (stop) set temperature.
The time required for the temperature rising / cooling process can be minimized, and the entire molding cycle can be shortened.

[0053]

As described above, according to the present invention, the time required for one molding cycle in hot runner type injection molding is minimized, and the metal molding material is stably injected into the mold. It is possible to provide a metal injection molding method using a hot runner capable of providing a high-quality metal molded product.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a vertical cross section of a general metal mold apparatus having a hot runner in a mold to which the method of the present invention can be applied.

FIG. 2 is a diagram illustrating steps of the injection molding process according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating steps of an injection molding process according to Embodiment 2 of the present invention.

FIG. 4 is a diagram illustrating steps of an injection molding process according to Embodiment 3 of the present invention.

FIG. 5 is a diagram illustrating steps of a conventional injection molding process.

[Explanation of symbols]

1 fixed side mold device, 2 movable side mold device, 3 manifold block, 4 (mold) sprue bush,
5 movable side mold plate 5, 6 movable side spacer, 7 mold product part, 8 eject pin, 9 eject plate,
10 molding machine nozzles, 11 runners, 12 sub runners, 13 nozzle parts.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Akira Ezaki             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd.

Claims (6)

[Claims] 1. A method for injection-molding a metal using a hot runner type metal mold apparatus, wherein nozzle temperature is controlled by using three preset temperatures in one injection molding cycle. A metal injection molding method characterized by carrying out. 2. The metal injection according to claim 1, wherein the three-stage set temperatures are a steady (stop) set temperature, an injection start set temperature, and a post-injection set temperature in the order of progress of the injection molding cycle. Molding method. 3. After the completion of injection, the temperature is steady (stopped) than the set temperature.
3. The metal injection molding method according to claim 2, wherein the set temperature is set high and the injection start set temperature is set higher than the steady (stop) set temperature. 4. A process for advancing from a steady (stop) set temperature to an injection start set temperature is started based on a cycle completion signal from the molding machine, and injection is started from the injection start set temperature based on an injection completion signal from the molding machine. By starting the process of advancing to the set temperature after completion, and starting the process of advancing from the set temperature after completion of injection to the steady (stop) set temperature based on the fact that the measured temperature has reached the set temperature after injection, The metal injection molding method according to any one of claims 1 to 3, wherein the operation of the injection molding cycle is performed once. 5. A process for advancing from a steady (stop) set temperature to an injection start set temperature is started based on a cycle completion signal from the molding machine, and injection is started from an injection start set temperature based on an injection completion signal from the molding machine. Once by starting the process of advancing to the set temperature after completion, and starting the process from the set temperature after completion of injection to the steady (stop) set temperature based on the fact that the preset time has been reached after completion of injection The metal injection molding method according to any one of claims 1 to 3, wherein the injection molding cycle is performed. 6. A process of starting from a steady (stop) set temperature to an injection start set temperature is started based on a cycle completion signal from the molding machine, and is injected from an injection start set temperature based on an injection completion signal from the molding machine. After the completion of the process of advancing to the set temperature, and when the measured temperature reaches the set temperature after the completion of injection, or the preset time after the completion of injection, whichever comes first, whichever comes first. 4. The injection molding cycle is operated once by starting a process from a set temperature after completion of injection to a steady (stop) set temperature based on the arrival. The metal injection molding method according to.