JPH0486236A - Preliminary heating device for mold - Google Patents

Abstract

PURPOSE:To enable molding operation to be achieved effectively, while when a mold is replaced, the set temperature for starting the molding operation is obtained in short time by keeping the temperature of the mold kept in a mold- stocker at preliminarily set temperature and by keeping the mold. CONSTITUTION:The codes of the molds M1-M2 received in each receiving chamber R1-R9, preliminarily hating temperature Ts5-Ts13 and controlling cycles t5-t13 of contact or break are set and are stored in common RAM 20. CPU 12 for PMC controls preliminary temperature of each receiving chambers R1-R9 i.e., each mold M1-M9 on the basis of the preliminarily heating temperature Ts5-Ts13 stored in a stable Tb. The molding conditions of various kinds are set, and then the temperatures Ts1-Ts4 be set of each heating zone of a heating chamber 1 and the temperature Tsm to be set of the mold are set, and when they are stored in common RAM 20, the CPU 12 for PMC sends the set temperature of the mold to the thermostat of the mold through an output-circuit 22. The thermostat of the mold automatically controls the temperature of the heat- exchanging medium which circulates in the mold so that the temperature of the mold reaches said set temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a mold preheating device for preheating and keeping a mold used in an injection molding machine warm.

BACKGROUND OF THE INVENTION Mold stockers for storing a plurality of molds have been known for some time.

Problems to be Solved by the Invention When starting injection molding, the mold installed in the injection molding machine must be maintained at a set temperature. Even if you try to start the molding operation, you cannot start the molding operation until the attached mold reaches the set temperature. Particularly when molding multiple types of molded products in small quantities, the mold must be replaced frequently, and each time the mold is replaced, the injection molding process continues until the mold installed in the injection molding machine reaches the set temperature. Stops molding operation.

Waiting is not efficient in terms of work efficiency.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a mold pre-temperature control device that heats and pre-temperatures molds stored in a mold stocker.

Means for Solving the Problems The present invention provides a mold stocker having storage chambers for storing a plurality of molds, each of which has a heat insulating structure, and a heater that heats each storage chamber and a heater that heats each storage chamber. Temperature sensors are provided to detect the temperature, and each of the temperature sensors detects the temperature of each storage chamber, and a control device controls on/off of each of the heaters so that the temperature reaches a set temperature.

In particular, by configuring the above-mentioned control device as a control device that controls the temperature of the cylinder of the injection molding machine, and controlling the temperature of each storage chamber of the mold stocker as well as the temperature of the cylinder, efficient production can be achieved. A mold pre-temperature control device was installed.

Function: The control device compares the temperature detected by the temperature sensor in each storage chamber with the set temperature set for each storage room, and controls the heater in each storage room so that the detected temperature becomes the set temperature. On/off control and pre-temperature control of the molds in each storage chamber to the set temperature. In particular, since the injection molding machine has a control device that controls the temperature of each heating zone of the nozzle and cylinder, this control device is also used to control the temperature of each storage chamber of the mold stocker.

Example FIG. 1 is a block diagram of essential parts of an embodiment of the present invention.

1 is a heating cylinder, 2 is a screw, and the heating cylinder 1 is divided into a plurality of heating zones N (N=4 in the example shown in FIG. 1), and each heating zone is provided with band heaters BHI to BH4.
is installed, and each band heater BH1 to BH4 is connected to the switch S.
It is connected to a power source 5 via WI to SW4 to heat the heating cylinder 1. Further, temperature sensors S1 to S4 are arranged in each heating zone to detect the temperature of each heating zone, and each temperature sensor S1 to S4 is connected to input terminals P1 to P4 of the temperature converter 4, respectively. It is connected.

Reference numeral 3 denotes a mold stocker for storing molds, and has a plurality of mold storage chambers. In this embodiment, there are nine storage chambers R1 to R9. Each storage chamber R1 to R9 is separated by a heat insulator (not shown) to prevent heat conduction between the storage chambers.
I-, I'm sitting. Furthermore, each of the storage chambers R1 to R9 is provided with heaters 5HI to SH9 that heat and keep the respective storage chambers warm, and temperature sensors SS1 to SS9 that detect the temperature of each of the storage chambers R1 to R9 are provided. There is. The heaters 5I11 to SH9 are connected to the power source 5 via switches SW5 to 5Wi3, respectively, and the temperature sensors SS1 to SS9 are connected to input terminals P5 to P i 3 of the temperature converter 4, respectively.

The temperature converter 4 connects each temperature sensor S1 to input to terminals P1 to I]13 in accordance with a selection signal output from an output circuit of a numerical control device (NC device) of a control device that controls the injection molding machine. The temperatures detected at S4 and SS1 to SS9 are converted into digital signals and output to the input circuit of the NC device.

Each of the switches SWi to SW1.3 is connected to an output circuit of the NC device, and is controlled on/off by a signal outputted via the output circuit.

Reference numeral 10 is a block diagram of an NC device as a control device.

The NC device 10 is a microprocessor for NC (hereinafter, C
It has a CPU 12 for a programmable machine controller (hereinafter referred to as PMC),
PMC CPU ], 2 is R that stores sequence programs etc. that control sequence operations of the injection molding machine.
A RAM 19 used for temporary storage of data is connected to the OM 18.

The NC CPU 1.1 has a ROM 14 that stores a management program that controls the entire injection molding machine, and a servo that drives and controls the servo motors of each axis for injection, mold clamping, screw rotation, ejector, etc. A circuit 17 is connected via a servo interface 16. Also, 2
0 is a non-volatile shared RAM consisting of bubble memory and CMOS memory, which controls the NC that controls each operation of the injection molding machine.
It has a memory section that stores programs, etc., and a setting memory section that stores various setting values, parameters, and macro variables.

13 is a path arbiter controller (hereinafter referred to as BAC), and the BAC 13 includes a CPU 1 for NC and a PMC.
CI) Ul-2, shared RAM20. Input circuit 21. Each bus of the output circuit 22 is connected, and the BAC 13 controls the buses to be used. Also, 24
is the BAC1 via the operator panel controller 23.
Manual data entry device with CRT display connected to 3 (
The CRT/MDI (hereinafter referred to as CRT/MDI) allows various commands and setting data to be input by operating various operation keys such as soft keys and numeric keys. Note that 15 is a RAM connected to the NC CPU i via a bus and used for temporary storage of data.

The output circuit 22 includes a temperature converter 4. Switch SW1~5Wi
3. Connected to a mold temperature controller (not shown) and other various actuators.

The input circuit 21 also includes a temperature converter 4, a mold temperature controller,
Connected to various other sensors.

In addition, each servo circuit 17 is connected to the servo motor of each axis, and is also connected to a position detector such as a pulse coder that detects the rotational position of the servo motor provided in each servo motor, and the speed of each servo motor. , to control the position.

In the above configuration, the NC device 10 has a shared RA
NC that controls each operation of the injection molding machine stored in M20
While the PMC CPU i 2 performs sequence control based on the program and parameters such as various molding conditions stored in the setting memory section and the sequence program stored in the ROM 18, the NC CPU 1.1
pulses are distributed to the servo circuits of each axis of the injection molding machine via the servo interface 16 to control the injection molding machine.

Injection molding operations, namely metering, mold clamping, and injection.

Operation processing controls such as holding pressure, cooling, direction opening, ejecting, etc. are performed in the same manner as in the past, and a description of the operations will be omitted.

Temperature control, which is a feature of the present invention, will be explained below.

FIG. 2 is an explanatory diagram of a table that stores preliminary temperature settings to be set for each storage chamber R1 to R9 when molds M to M9 are stored in the mold stocker 3.
b is provided in the shared RAM 20.

When storing the molds M1 to M9 in the storage chambers R1 to R9, respectively, the CRT/MD I 24. Operate to switch the CRT screen to the temperature setting monitor screen, and as shown in Figure 2, change the settings to each storage room R1 to
Set the name (core code) ML to M9 of the mold stored in R7, and set the preheating temperature Ts5 to Ts5 for the mold.
Set T s 1-3. Furthermore, the on/off control periods t5 to t i 3 of each heater 39 are also set. Note that the on/off control periods may all be the same, and in this case, they may be fixedly set in advance so that there is no need to set them when storing the mold.

The codes and preheating temperatures Ts5 to Ts of the molds M] to M9 stored in each storage chamber R1 to R9 in this way
i3, and further on/off control period t5 to t1-3
is set and stored in the shared RAM 20, the PMC CPU], 2 controls each storage room R1 based on the preheating temperatures Ts5 to T81-3 stored in this table Tb.
~R9, that is, perform preliminary temperature control for each of the molds M1 to M9. In addition, as in the past, when various molding conditions are set and the set temperatures TSI to TS4 of each heating zone of the heating cylinder 1 and the mold set temperature Tsm are set and stored in the shared RAM 20, the PMC CPU 1- 2 sends the mold set temperature to the mold temperature controller via the output circuit 22 as in the past, and the mold temperature controller adjusts the temperature of the heat exchange medium circulating inside the mold to reach the set temperature. control automatically.

Moreover, CP U12 for PMC is shown in FIG. 4(a).

The temperature control shown in the flowchart in (b) is repeatedly executed at predetermined intervals. Note that this temperature control processing cycle is sufficiently shorter than the on/off cycle for controlling the on/off of the band heaters B1 (1 to BH4) of the heating zone and the heaters SHI to SH9 of each storage chamber.

PMC CPU], 2 first sets the index i to 1 in step S], 00), flags F2-1- to F213, Fi provided for each heating zone and storage chamber.
l~F 1. -]-3, it is determined whether the flags F2i and Fli corresponding to the index i are set to 1 (step S10], 5iO2). Note that these flags F1-1 to F1. -13F2-1 to F2-13 are set to 0 by default. Flag F2i, TJ
If i is not "1", PMC CPU ], 2 switches the temperature converter 4 via the BΔC 13 and the output circuit 22, and connects the temperature sensor manually to the terminal i of the temperature converter 4 indicated by index 1. S1-S4. The detected temperatures from SSI to SS9 are input to the input circuit 21, and the detected temperature Tai from this temperature sensor is read (step 5i0).
3). Next, the heater corresponding to terminal i (if i is 1-4, band heater B H1-131-14, if i is 5-1
3, the heater S[]1 corresponding to storage chambers R1 to R9
~S Ii 9) When turning on the previous time, the corresponding terminal i
The value of register E11, which stores the temperature deviation detected in If i is 5 to 13, the set temperature Ts is set to the storage chambers R1 to R9 (5 to Ts13).
The temperature deviation is obtained by subtracting the detected temperature Taj read in step 5103 from the temperature difference and stored in the register Eli (step 5104.S/105). Then, the temperature deviation value stored in the register Eli is added to the register ESI that stores the integrated value of the temperature deviation (step 81.06). Next, the on-time t, o n is calculated by performing the calculation shown in the first equation below.
Calculate (Step 5107゜ton=1・El i+2・Esi+3・(
Eli−EOi) (1) In the first equation, Kl is 2. 3 is proportional, integral, and differential gain in temperature control, Eli, ESi, EO
i means the value of each register, that is, the currently detected temperature deviation, the integrated value of the temperature deviation, and the previously detected temperature deviation.

The on-time ton obtained in this way is set for the heating zone or storage chambers R1 to R9 corresponding to the terminal (i), and the temperature control period (on/off period) tpi (if i is 1 to 4, the heating zone If the temperature control period stored in the work memory is 5 to 13, the temperature control period tp5 to t set in the table 'I''l)
I) 1.3 correspond to each other. ), and only when it is larger, change the on time to this temperature control cycle (on/off cycle) tpi (step 5l-08, S
l, 09).

That is, the entire period of the temperature control cycle (on/off cycle) is the on time. Next, the temperature control cycle (on/off cycle)
Subtract the on time ton from tpi to find the off time toff (step 5l-1, 0), and set the timers Tli and T2i.
On-time ton and off-time toff are set, respectively (step S]1-1).

S11.2).

Then, timer T11 is started and BACl
, 3. The switch SWi is turned on via the output circuit 22, the band heater BHi of the heating zone corresponding to the index i or the heaters S1-11 to SH9 of the storage chambers R1 to R9 are activated, and the flag F1i is set to 1. (Step 5)
ij3. Sl14,5il-5). Next, it is determined whether or not the timer Tli has timed up (step 8116).
At the beginning, there is no time up, so step 5122
, the index i is incremented by 1, and it is determined whether the index i is equal to or less than 13 in the number of controlled heating zones and storage chambers (step 5l-23); if it is 13 or less, step 5101
Return to step 8101 and repeat the processing from step 8101 onwards.

Immediately after the start of operation, flags F2-1 to F2-1.3°Fl
-1 to F 1-13 are 0 by default, so the index i
Step S i O] ~ 5116 until exceeds 13,
5122. The process of Sl, 23 is repeated, and each band heater B H1 to BH3 and each storage chamber R1 to R
The heaters SHI to SH9 for 9 are the calculated on-time heating cylinders and the molds M1 to M in the storage chambers R] to R9.
9 will be heated.

In this way, each band heater BHI to BH3, each heater S
When the operation of i-11 to SH9 is started and the index i exceeds 13, the number of band heaters and storage chambers, the processing of the processing cycle ends.

In the next processing cycle, each flag F1. Since −1 to F113 are set to 1, steps 5100 and 5
Process the IOI and proceed from step 5102 to step 81
16, it is determined whether or not the timer T1i has timed up, and if the timer has not timed up, the process proceeds to step 512.
2, the index j is incremented by 1, and if the index i is 13 or less, the process returns to step 101 and the index j is 13.
Steps 5101, 5i02. Si1.6
゜Si, 22. The process of Si, 23 is repeated to complete the process of the corresponding process cycle.

After the next processing cycle, the above-described processing is repeated, but when it is detected in step 5116 that the timer Tri has timed up, the switch SWi corresponding to the index i is turned off via the BAC 13 and the output circuit 22. Step 81
1.7) Set the flag F11 and 0XF2i to 1 (step 5118), and start the timer T2i to set the off time 1 set in step 5112: o
Step S11.9) to start measuring [f f n] Step S11.9), determine whether or not the time has expired for the tie 7T21 (Step 81.20); if not, proceed to Step 5122, and increment index 1 by 1. , index] If the number of months has not exceeded 3, the process returns to step S]01 and the above-described process is repeated.

In this way, when the timer T11 times up and the on time has elapsed, the switch is turned off and measurement of the off time is started.

Then, from the next cycle, if the flag F2i is 1 and the 31st measurement of the off time has started, the process moves from step 5101 to step 31.20, where it is determined whether or not the timer T2j has timed up. If the time is running, the process moves from step 5102 to step 8116, and the above-described process is repeated.

Further, when it is detected in step 5120 that the timer T2i has timed up, the flag F 2 i is set to 0. In this way, flag F2i.

When Fli becomes 0, the processes from step 8103 described above will be performed in the next processing cycle.

The PMC CPU 1.2 repeats the above-mentioned processing every processing cycle, turns on/off each switch SW1 to SW5WI-3, and turns each band heater B)I] to BT(4, each heater SH] to Each heating zone or mold 17 is heated by S H9, and PTD (proportional, integral, differential) control is performed so that each heating zone or mold 17 reaches a set temperature.

Also, when setting temperature conditions for injection molding or monitoring temperature, if the CRT device is switched to the temperature condition setting and monitoring screen, the PMC CPU 1-
2 reads out the set mold temperature Tsrn and temperature Tsl to Ts4 of each heating zone and each stage which have already been set and stored in the shared RAM 20, and displays them on the CRT screen together with a diagram of the mold and heating cylinder as shown in FIG. In addition, the code (Ml to M9) of the mold stored in each storage chamber and the preset temperature Ts5 to Ts13 set for that storage chamber.
Display. Furthermore, the mold temperature Tam detected by the mold temperature controller and the terminals of the temperature converter 4 (temperature sensors S1 to S4 of each heating zone or temperature sensors SSI to 5S9 corresponding to the storage chambers R1 to R9) The temperatures Ta1 to Ta13 detected by each temperature sensor are displayed on the screen in correspondence with the set temperature. Therefore, the current value of the mold temperature, the current temperature of each heating zone, each mold M in the mold stocker 3] ~
The current temperature of M9 can also be monitored at the same time.

In the above embodiment, the temperature control of the heating cylinder 1 and the temperature control of the mold of the mold stocker 3 are controlled simultaneously, but the preliminary temperature control of the mold stocker 3 is performed with high accuracy like that of the heating cylinder. Since there is little need for temperature control, the preliminary temperature control of the molds M1 to M9 in the mold stocker 3 may be performed at a different cycle from the temperature control of the heating cylinder. The control in this case is shown in Figure 4 (a), (+)
), except that the processing cycle is longer.

Further, the pre-temperature control setting temperature Ts5~]'s-13 may be a pre-temperature setting temperature for each mold during molding, or a pre-temperature control temperature different from the pre-temperature setting temperature during molding. If the pre-temperature control temperature and the set temperature during molding are the same, there is no need to set the mold temperature again when setting the molding conditions, and you can simply set the mold code and set the mold corresponding to that mold. The temperature (preliminary temperature control temperature) may be set.

Moreover, instead of controlling the temperature of all the molds stored in the mold stocker 3 to a preset temperature as in the above embodiment,
If the order in which the molds are to be used is determined, the above-mentioned temperature control is performed using the heater and temperature sensor in only one storage chamber, and the mold to be used next is stored in this temperature-controllable storage chamber. When setting the molding conditions, each set temperature for the mold to be used may be set, and a preliminary set temperature may be set for the temperature controllable storage chamber of the mold stocker. In this case, for the other storage chambers of the mold stocker, the temperature of each storage chamber may be detected using a bimetal or the like, and each storage chamber heater may be turned on/off. In addition, the bimetal temperature control of other storage rooms should be performed all at once, so that only the storage room whose temperature can be controlled is surrounded by heat insulating material, and the other storage rooms are not designed to have an insulated structure.

Effects of the Invention In the present invention, the molds stored in the mold stocker are kept warm at a preset temperature, so when the molds are replaced, the molding operation can be started in a short time. It is possible to reach the set temperature for molding, and the molding work can be carried out efficiently. It is particularly suitable for molding a wide variety of Ogawa molded products by exchanging molds within a short period of time.

[Brief explanation of drawings]

Figure 1 is a block diagram of the main parts of the present invention, Figure 2 is an explanatory diagram of a table that stores preliminary set temperatures for molds in the mold stocker in the same embodiment, and Figure 3 is an explanation of temperature condition setting and monitor screen. 4(a) and 4(b) are flowcharts of temperature control. ]... Heating cylinder, 2... Screw 3 mold stocker, 4... Temperature converter, 5... Power supply, BHI~BH
4...Band heater, S H]--S H9 heater, S1-S4. SSI~SS9...Temperature sensor, SWI~
5W13... Switch.

Claims (2)

[Claims] (1) A storage chamber is provided to store a plurality of molds, each storage chamber is constructed with a heat-insulating structure, and a heater is installed to heat each storage chamber, and a temperature sensor is installed to detect the temperature of each storage chamber. A mold pre-temperature control device comprising a mold stocker and a control device that detects the temperature of each storage chamber with each of the temperature sensors and controls on/off of each of the heaters to control the temperature of each storage chamber to a set temperature. (2) The control device is a mold pre-temperature adjustment device that is configured with a control device that controls the temperature of the cylinder of the injection molding machine, and that controls the temperature of each storage chamber of the mold stocker as well as the temperature of the cylinder.