JP4944079B2 - Automatic temperature rise control method for molding machine - Google Patents

Description

  The present invention relates to an automatic temperature rise control method for a molding machine, and more particularly to an automatic temperature rise control method for a molding machine such as an extrusion molding machine or an injection molding machine.

  An injection molding machine, which is an example of a molding machine, is configured such that a screw is rotatably disposed inside a heating cylinder (barrel portion) so that the inside of the heating cylinder can be advanced and retracted along the axial direction. A nozzle (injection port) is provided at the tip of the heating cylinder, and a plurality of heaters are arranged on the outer peripheral portion of the heating cylinder. The screw rotates while being advanced and retracted inside the heating cylinder by a drive motor, whereby the resin chip of the raw material charged into the cylinder from the hopper is heated and melted, and the screw is injected from the nozzle and molded.

In this type of molding machine, the outer peripheral portion of the heating cylinder is divided into a plurality of heating sections (also referred to as heating zones) along the axial direction, and a heater is disposed in each heating section. A temperature sensor is provided in the vicinity of each heater. The temperature measurement unit has inputs from each temperature sensor, and controls the temperature of the heater based on the temperature of the heating section measured by the temperature measurement unit and the target temperature stored in the target temperature setting unit. When raising the temperature of each heating section, the heating section with the slowest time to reach the target set temperature is set as the master section, and the heating section other than the master section is set as the slave section (see Patent Document 1).
JP 2005-35090 A

  In the automatic temperature raising control method for a molding machine disclosed in Patent Document 1, the temperature of the slave section is raised simultaneously in accordance with the target set temperature arrival rate of the master section. When selecting the master section, the section where the target temperature arrival time is the slowest using the “temperature gradient data” parameter and “dead time” parameter set in each section in order to estimate the time to reach the target temperature in advance Is the master section.

The automatic Atsushi Nobori control method for a conventional molding machine, since in this way it is necessary to set the master section using these parameters, when selecting the master section, the master section and the slave section is due to disturbance at the time of Atsushi Nobori There is a problem that it is affected by temperature changes and errors in these parameters.

  The present invention has been made to solve the above-mentioned problems, and the object of the present invention is that it is not necessary to set such a “temperature gradient data” parameter and a “dead time” parameter. It is an object of the present invention to provide an automatic temperature rise control method for a molding machine that can simultaneously raise the temperature of a master section and a slave section without being affected by the error of the above.

  An automatic temperature rise control method for a molding machine according to the present invention is an automatic temperature rise control method for a molding machine that controls the temperature rise of the molding machine when the barrel portion of the injection molding machine is heated in a heating zone divided into a plurality of parts. A heater provided for each heating zone, a temperature sensor provided for each heating zone, a temperature measurement unit for inputting from the temperature sensor, a heater control unit for controlling the heater, and a target of the heater A target temperature setting unit that sets and stores a temperature; a temperature control unit that controls the temperature of the heater based on the temperature of the heating zone measured by the temperature measurement unit; and the target temperature stored in the target temperature setting unit; The heating zone having the lowest target temperature attainment rate measured every cycle of the temperature control is set as the master zone, and the heating zone is simultaneously heated toward the target temperature, and the heating zone is the master zone. The heating zone other than the star zone as a slave zone, said slave zone, characterized by temperature increase control based on the attainable heating degree of the master zone.

  The automatic temperature rise control method for a molding machine of the present invention is characterized in that the target temperature set by the target temperature setting unit can be individually set for each of the plurality of heating zones.

  According to the present invention, there is provided an automatic temperature rise control method for a molding machine that does not require parameter setting and can simultaneously raise the temperature of a master section and a slave section without being affected by temperature change due to disturbance or parameter error. Can do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an example of the structure of a molding machine for carrying out a preferred embodiment of an automatic temperature rise control method for a molding machine of the present invention.

  The molding machine 10 shown in FIG. 1 is an injection molding machine. The molding machine 10 includes a heating cylinder 11, a plurality of heaters H1, H2, H3, H4, and H5, and a plurality of temperature sensors 12, 13, 14, 15, 16, a screw 27, a temperature measurement unit 17, a heater control unit 18, a temperature control unit 19, a target temperature setting unit 20, a target temperature storage area 21, and a hopper 22.

  The molding machine 10 shown in FIG. 1 is an apparatus that performs injection molding using a resin chip 23 as a raw material, and the heating cylinder 11 is also called a barrel portion and is a substantially cylindrical member. A nozzle (also referred to as an injection port) 24 is provided at the tip of the heating cylinder 11. Inside the heating cylinder 11, a screw 27 is disposed so as to be able to advance and retract along the axial direction CL by the drive of the drive unit 25 and to be rotatable. The resin chip 23 supplied from the hopper 22 can be supplied to the material storage portion 26 inside the heating cylinder 11, and the screw 27 rotates and advances along the axial direction CL, whereby the molten resin is injected from the nozzle 24. To do.

  As shown in FIG. 1, heaters H <b> 1 to H <b> 5 as a plurality of ring-shaped heating bodies are arranged along the axial direction CL on the outer peripheral portion of the heating cylinder 11. These heaters H1 to H5 are arranged at intervals, and the heaters H1 to H5 divide the outer peripheral portion of the heating cylinder 11 into a plurality of heating sections (also referred to as heating zones) Z1 to Z5. That is, each heater H1-H5 is provided for every heating area Z1-Z5, and each heating area Z1-Z5 is formed in order from the nozzle 24 side to the screw 27 side.

  As shown in FIG. 1, the temperature sensors 12, 13, 14, 15, and 16 are arranged for the corresponding heating sections Z <b> 1 to Z <b> 5. Thereby, each temperature sensor 12, 13, 14, 15, 16 can each measure the temperature of the corresponding heating area Z1-Z5.

  The temperature measuring unit 17 is electrically connected to each temperature sensor 12, 13, 14, 15, 16. A temperature measurement signal obtained by measuring the temperature in each of the heating zones Z1 to Z5 is input to the temperature measurement unit 17 from each temperature sensor 12, 13, 14, 15, 16.

  As shown in FIG. 1, the heater control unit 18 is electrically connected to the heaters H1, H2, H3, H4, and H5. The heater control unit 18 can individually heat the heaters H1, H2, H3, H4, and H5 by individually energizing the heaters H1, H2, H3, H4, and H5.

  As shown in FIG. 1, the temperature control unit 19 is electrically connected to the temperature measurement unit 17 and the heater control unit 18. The temperature control unit 19, the temperature measurement unit 17, and the heater control unit 18 constitute a controller for PID control. The temperature control unit 19 is electrically connected to the target temperature setting unit 20, and the target temperature setting unit 20 has a target temperature storage area 21.

  The target temperature setting unit 20 can set the target temperature value stored in advance in the target temperature storage area 21 as the target temperature of each of the heaters H1 to H5, and the target temperature set by the target temperature setting unit 20 Can be individually set for a plurality of heating sections (also referred to as heater channels or heating zones). The temperature control unit 19 performs temperature control of the heaters H1 to H5 based on the temperatures of the heating sections Z1 to Z5 measured by the temperature measurement unit 17 and the target temperatures stored in the target temperature setting unit 20. It has become.

  In a preferred embodiment of the automatic temperature rise control method for a molding machine according to the present invention, a heating zone having the lowest target temperature attainment rate that is measured at each temperature control cycle is obtained by simultaneously raising the temperature of a plurality of heating zones toward the target temperature. Is a master section (also called a master zone), and a heating section other than the master section is a slave section (also called a slave zone). In the slave section, the temperature rise is controlled based on the degree of temperature rise in the master section.

  As described above, the heating section with the lowest temperature arrival rate in each heating section is set as the master section for each temperature control period. According to such a method of determining the master section, even if the heating section is heated up due to disturbance or for some reason, the master section is determined by determining the heating section with the lowest target temperature arrival rate as the master section. And the slave section can reach the target temperature at the same time. In other words, without fixing the master section, the heating section having the lowest target temperature arrival rate is set as the master section for each temperature control period, and thereafter, the slave section is heated in accordance with the temperature arrival ratio of the master section.

  In a preferred embodiment of the automatic temperature rise control method for a molding machine of the present invention, the target temperature arrival rate is calculated for each temperature control period in a plurality of heating intervals, and the heating interval with the lowest target temperature arrival rate is set as the master interval. The temperature of the slave section is controlled in accordance with the temperature arrival rate of the master section (rm: also called the degree of temperature increase). Even if the target temperature attainment rate changes between multiple heating sections due to a temperature change due to disturbance during the temperature rise, the master section and the slave section can be switched to continue the simultaneous temperature increase. it can.

  On the other hand, in the prior art, the section where the time to reach the target set temperature at the time of temperature rise is determined as the master section, and the sections other than the master section are set as slave sections, and the slave section is matched to the target set temperature arrival rate of the master section. When the master section is selected, the section with the latest target temperature arrival time according to the “slope data” parameter and the “dead time” parameter set for each section is set as the master section. Since these parameters are necessary as described above, the temperature of the master section and the slave section is affected by a temperature change due to a disturbance or an error of these parameters when the temperature rises.

  Next, with reference to FIG. 2, a preferred embodiment of the automatic temperature rise control method for a molding machine according to the present invention will be described with reference to an operation flowchart of a simultaneous temperature rise function in a plurality of heating sections.

  The operation flowchart shown in FIG. 2 has steps S1 to S11. In the following description, for easy understanding, the two heating sections are represented by CH1 and CH2, and the heating section CH1 is an initial master section, and the heating section CH2 is an initial slave section.

In FIG. 2, the final target temperature of the heating section CH1 is denoted by SV1, and the final target temperature of the heating section CH2 is denoted by SV2. Further, the current temperature of the heating section CH1 shown in PV _1, indicating the current temperature of the heating section CH2 in PV _2. The target temperature of the master section is indicated by SV _m , and the initial temperature of the master section is indicated by PV _ocm .

Further, (also referred to as arrival rate) progress rate is indicated by r _m, showing a progress rate dead zone at r _fi. The progress rate r _m is the heating section CH1, CH2 is that the target temperature reaches rate reaches the target temperature at the time of heating. Furthermore, the progress rate dead zone r _fi is provided. This progress rate dead zone r _fi is a unique solution in the present invention, and the progress rate dead zone r _fi is, for example, almost composed of two heating sections CH1 and CH2. This is provided to avoid a phenomenon in which the master section and the slave section are frequently switched between the two heating sections CH1 and CH2 for some reason during the temperature increase in the case of the same temperature increase rate.

  Here, a preferred embodiment of the automatic temperature rise control method of the molding machine of the present invention implemented using the molding machine 10 shown in FIG. 1 will be described according to the steps shown in the operation flowchart of the simultaneous temperature rise control function of FIG. . As described above, in order to make the explanation easy to understand, in FIG. 2, the heating section CH1 is an initial master section and the heating section CH2 is an initial slave section.

  In FIG. 2, the temperature rise control is started, and in step S1, an operation of setting the target temperature SVi of each heating section set by the user to the final target temperature SVi 'is started. In step S2, it is determined whether or not the heating section CH1 and the heating section CH2 are in the simultaneous heating mode. If the simultaneous heating mode is in the step, the process proceeds to step S3. If it is not the simultaneous temperature raising mode in step S2, the process proceeds to step S10 and the subsequent processing is performed.

  In step S3, when initial processing is performed instead of simultaneous temperature increase start, the process proceeds to step S4, or when initial processing is already completed and simultaneous temperature increase is started, the process proceeds to step S5.

In step S4, i at the end of the variable represents the heating section number, and m at the end represents the variable in the master section in particular. At the moment when the simultaneous temperature _raising function is started, the current temperature PV _0i of each heating section CH1, CH2 is stored, and the same value is stored as the current temperature PV _0ci . The progress rate r ₁ of the heating section CH1 is master section and progress ratio r _m, the final target temperature SV1 of the heating section CH1 is master section and a final target temperature SV _m of master section, the heating section CH1 is master section The current temperature PV ₁ is stored as the initial temperature PV _ocm of the master section.

Next, in step S5, it is determined whether the master section is the heating section CH1 or the heating section CH2. When the master section is not the heating section CH1 but the heating section CH2, the process proceeds to step S6, and the progress rate r _i of the slave section (heating section CH2) is calculated by the following equation.

_{(PV i -PV 0i) / (} SV i -PV 0i) = r i

In step S5, if the heating section CH1 is the master section as it is, the process proceeds to step S11 and the process of step S10 is performed.

Next, in step S7, it is determined whether or not the progress rate r _i of the slave section is smaller than (progress ratio r _{m of the} master section−progress ratio dead zone r _fi ). The progress rate dead zone r _fi is a phenomenon in which the master section and the slave section are frequently switched for some reason during the temperature increase between the heating sections CH1 and CH2 when the heating sections CH1 and CH2 have almost the same temperature increase progress rate. Used to avoid.

In here, the progress rate of the slave section is (percentage of completion master section r _m - progress rate dead zone r _fi) is smaller than the proceeds to step S8. Conversely, the progress rate of the slave section is (progress rate of the master segment r _m - progress rate dead zone r _fi) is greater than the shifts to the step S9, the process of step 10.

In step S8, since the progress rate of the slave section is smaller than (progress ratio r _m -progress rate dead zone r _fi ) of the master section, the data of the slave section is replaced with the data of the master section, i at the end of the heating section. Becomes m. The progress rate r _i of the slave section becomes the progress rate r _{m of the} master section, the final target temperature SV _i of the slave section becomes the final target temperature SV _m of the master section, and the current temperature PV _i of the slave section becomes the initial temperature PV of the master section. _0cm next, and the current temperature PV _i slave section becomes the current temperature _{PV 0ci.}

  In step S9, the final target temperature SVi 'of the slave section is calculated by the following equation based on the progress rate of the master section.

_{((PV m -PV 0cm) /} (SV m -PV 0cm)) · (SV i -PV 0ci) + PV 0ci = final target temperature SVi slave section '

Thereafter, in step S10, the temperature controller 19 shown in FIG. 1 instructs the heater controller 18 to heat each heating section so that the final target temperature SVi ′ of the slave section is reached. And in order to process all the heating sections regularly for every temperature control period, it returns to step S2 and repeats and the process after step S2 is repeated for every temperature control period.

  FIG. 3 (A) shows a case where the master zone and the slave zone are not interchanged when the heating zone CH1 is the master zone in the simultaneous temperature rise. FIG. 3B shows a case in which the master section and the slave section are interchanged by simultaneous temperature increase, and the rate of increase (degree of temperature increase) decreases temporarily during the temperature increase due to some cause in the heating section CH2 temporarily. The case where the heating section CH2 becomes the master section instead of the heating section CH1 is shown. 3A and 3B, the vertical axis is temperature, and the horizontal axis is elapsed time.

  In the case where the master section and the slave section shown in FIG. 3 (A) are not interchanged, the heating section CH1 is the master section, the heating section CH2 is the slave section, and the temperature rise in the heating section CH1 is represented by the heating data line L1. The state of temperature increase in the heating section CH2 is indicated by the heating data line L2. The time point when the heating section CH1 reaches the final target temperature is indicated by G1, the time point when the heating section CH2 reaches the final target temperature is indicated by G2, and the time point when the temperature rising point G2 achieves the temperature increase is indicated by G2. Faster than G1.

  In FIG. 3A, since the inclination of the heating data line L1 in the heating section CH1 (master section) is always lower than the inclination of the heating data line L2 in the heating section CH2 (slave section), the temperature control cycle in the heating section CH1. The target temperature attainment rate measured every time is the lowest compared to the heating section CH2. Therefore, in the simultaneous temperature increase, the master section and the slave section are not interchanged, and in the heating section CH2 that is the slave section, the temperature increase control is performed based on the degree of temperature increase in the heating section CH1 that is the master section. It is possible to reach the final target temperature in both the section and the slave section at the same time.

  On the other hand, in the case where the master section and the slave section shown in FIG. 3B are interchanged, the state of temperature increase in the heating section CH1 is indicated by the heating data lines L11, L12, and L13, and the temperature increase in the heating section CH2 is shown. The state is indicated by heating data lines L21, L22, and L23.

  As shown by the heating data lines L21 and L22, when the rate of temperature increase in the heating section CH2 decreases for some reason in the period D, the target temperature arrival rate in the heating section CH2 is the lowest in this period D. The heating section CH2 becomes the master section, and the heating section CH1 is temporarily replaced with the slave section.

  In this way, the heating section CH2 temporarily becomes the master section, so that the target temperature arrival rate of each heating section is compared for each temperature control period, and the lowest heating section is set as the master section to the master section. It is replaced by a section.

By determining the master section as in the example shown in FIG. 3B, the heating section CH2 is set in the period D with the lowest target temperature attainment rate even when the temperature rises due to disturbance or for some reason. By setting it as a master area, heating area CH1 becomes a slave area. After that, according to the temperature arrival rate (r _m ) of the master section, that is, the degree of increase in the temperature of the master section, the slave section can be heated and the final target temperature can be reached at the same time in both the master section and the slave section. It is.

Thus, in the embodiment of the present invention, a plurality of heating sections (also referred to as heater channels or heating zones) do not fix the master section, but calculate the target temperature arrival rate for each temperature control period, The heating section with the lowest target temperature attainment rate is determined as the master section, and the slave section is heated in accordance with the temperature attainment rate (r _m ) of the master section. And even if the target temperature attainment rate changes between the heating sections due to disturbances during the temperature rise in the master section and the slave section, the master section and the slave section can be replaced to determine the master section. Simultaneous temperature increase in the section and the slave section can be continued, and the final target temperature can be reached simultaneously in the master section and the slave section.

  The heating rate progress rate (target temperature arrival rate) is introduced for each heating zone, the heating zone with the slowest progress rate is set as the master zone, the heating zone other than the master zone is set as the slave zone, PID control is performed toward the target temperature set by the user, but the slave section is set to a new target temperature corresponding to each progress rate and controlled toward this target temperature.

  An automatic temperature rise control method for a molding machine according to the present invention is an automatic temperature rise control method for a molding machine that controls the temperature rise of the molding machine when the barrel portion of the injection molding machine is heated in a heating zone divided into a plurality of parts. Set the target temperature of the heater, the heater provided for each heating zone, the temperature sensor provided for each heating zone, the temperature measurement unit that inputs from the temperature sensor, the heater control unit that controls the heater, A target temperature setting unit for storing, a temperature of the heating zone measured by the temperature measuring unit, and a temperature control unit for controlling the temperature of the heater based on the target temperature stored in the target temperature setting unit, and a plurality of heating zones Heating is completed at the same time toward the target temperature, and the heating zone with the lowest target temperature arrival rate measured at each temperature control cycle is set as the master zone, and heating zones other than the master zone are set as slave zones. Buzon is characterized by raising the temperature control based on the attainable heating degree of the master zone.

  Accordingly, it is not necessary to set the “temperature gradient data” parameter and the “dead time” parameter, and the master section and the slave section can be simultaneously heated without being affected by the temperature change due to the disturbance or the parameter error.

  The automatic temperature rise control method for a molding machine of the present invention is characterized in that the target temperature set by the target temperature setting unit can be set individually for each of a plurality of heating zones. Thereby, temperature control of each heating zone can be performed by setting a target temperature individually for each heating zone.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage.

  The molding machine 10 shown in FIG. 1 shows a combination example of five heaters H1 to H5 and five temperature sensors 12 to 16 as an example, but not limited to this, a combination of two heaters and two temperature sensors, A combination of three heaters and three temperature sensors, a combination of four heaters and four temperature sensors, or a combination of six or more heaters and six or more temperature sensors may be employed. The molding machine may be an injection molding machine or an extrusion molding machine.

  Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

It is a figure which shows the preferable example of the molding machine for implementing preferable embodiment of the automatic temperature rising control method of the molding machine of this invention. It is an operation | movement flowchart of the simultaneous temperature rising function of several heating area. FIG. 3 (A) shows a case where the master zone and the slave zone are not interchanged when the heating zone CH1 is the master zone in simultaneous heating, and FIG. 3 (B) shows the star zone in the simultaneous heating. The figure shows a case in which the slave section is replaced, and the heating section CH2 has a rate of increase during the temperature rising due to some cause, and the heating section CH2 temporarily becomes the master section instead of the heating section CH1. It is.

Explanation of symbols

10 Molding machine 11 Heating cylinder (barrel part)
12 to 15 Temperature sensor 17 Temperature measurement unit 18 Heater control unit 19 Temperature control unit 21 Target temperature storage area 22 Hopper 27 Screw H1 to H5 Heater Z1 to Z5 Heating section (heating zone)
CH1 heating section (master zone at initial setting)
CH2 heating section (slave zone at initial setting)

Claims (2)

An automatic temperature rise control method for a molding machine for controlling a temperature rise of a molding machine when heating a barrel portion of an injection molding machine in a plurality of heating zones, the heater provided for each heating zone, and the heating A temperature sensor provided for each zone; a temperature measurement unit that performs input from the temperature sensor; a heater control unit that performs control of the heater; a target temperature setting unit that sets and stores a target temperature of the heater; A temperature control unit that controls the temperature of the heater based on the temperature of the heating zone measured by the temperature measurement unit and the target temperature stored in the target temperature setting unit;
Heating of the plurality of heating zones is simultaneously completed toward the target temperature, and the heating zone other than the master zone is defined as the master zone having the lowest target temperature arrival rate measured at each temperature control cycle. Zone as slave zone
An automatic temperature rise control method for a molding machine, wherein the slave zone performs temperature rise control based on a temperature rise arrival degree of the master zone.   The method of claim 1, wherein the target temperature set by the target temperature setting unit can be set individually for each of the plurality of heating zones.

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