WO2023090262A1

WO2023090262A1 - Molding machine and spray device

Info

Publication number: WO2023090262A1
Application number: PCT/JP2022/042032
Authority: WO
Inventors: 一康竹井
Original assignee: 芝浦機械株式会社
Priority date: 2021-11-16
Filing date: 2022-11-11
Publication date: 2023-05-25
Also published as: JP2023073623A

Abstract

A die casting machine 1 repeats a molding cycle MC, and has a machine body 3, a cooling unit 13, and a control device 5. The machine body 3 performs mold closing, injection, and mold opening in each molding cycle in sequence. The cooling unit 13 cools a die 101 in each molding cycle. The control device 5 controls the cooling unit 13 on the basis of a signal from a temperature sensor 59 for detecting the temperature of the die 101. The cooling unit 13 includes a spray device 15 for spraying toward the die 101 before mold closing in each molding cycle. The control device 5 controls the operation of the cooling unit 13 on the basis of the temperature difference between a first temperature D1 detected by the temperature sensor 59 before the spraying and a second temperature D2 detected by the temperature sensor 59 after the spraying in the molding cycle in which the first temperature D1 was detected.

Description

Molding machine and spray equipment

The present disclosure relates to a molding machine and a spray device used in the molding machine. A molding machine fills a mold cavity with a molding material to obtain a molded product, and is, for example, a die casting machine or an injection molding machine. The spray device, for example, sprays the mold with a mold release agent.

It is known that the temperature of the mold affects the quality of the molded product when the molding material is filled into the cavity of the mold to obtain the molded product (for example, Patent Documents 1 to 3 below). It is also known that a release agent or the like sprayed onto the mold affects the temperature of the mold (Patent Documents 1 and 2).

Patent Document 1 discloses a molding machine that sprays at multiple locations on the mold. This molding machine has temperature sensors at multiple locations on the mold, and based on the values detected by the multiple temperature sensors, mold release agents are sprayed at multiple locations on the mold so that the temperature of the mold becomes uniform. control the amount. In addition, this molding machine detects the temperature before spraying in each molding cycle, compares the temperature detected in the previous molding cycle with the temperature detected in the current molding cycle, and determines the temperature in the current molding cycle. determines the amount of release agent to be sprayed.

Patent document 2 discloses a spray system that sprays by sequentially moving a spray head to a plurality of blocks obtained by dividing the inner surface of the mold. This system uses a non-contact thermometer mounted on the spray head to detect the temperature of the block immediately before spraying, and sets the spray discharge pattern based on that temperature.

Patent Document 3 discloses a detection device that detects a sign of temperature abnormality based on an image of mold temperature obtained by thermography.

JP-A-10-193070 JP 2015-150617 A JP 2019-84556 A

With the techniques of Patent Documents 1 and 2, it may be difficult to set the temperature of the mold to the target value. For example, even if the ejection amount of the release agent is set by multiplying the temperature difference between the target value of the mold temperature and the measured value of the mold temperature by a predetermined coefficient, if the above coefficient is not set appropriately, the mold may is not a target value. Also, for example, changes in the condition of the equipment for cooling (eg clogging of channels or pressure fluctuations) or changes in the ambient temperature may change the appropriate values of the above factors. Accordingly, it would be desirable to provide a molding machine and spray apparatus that can improve the accuracy in controlling the temperature of the mold.

A molding machine according to one aspect of the present disclosure repeats a molding cycle. The molding machine has a machine body, a cooling section, and a control device. The machine body sequentially performs mold closing, injection and mold opening within each molding cycle. The cooling section cools the mold within each molding cycle. The control device controls the cooling section based on a signal from a sensor that detects the temperature of the mold. The cooling section includes a spray device that sprays the mold prior to closing within each molding cycle. The controller controls the temperature difference between a first temperature sensed by the sensor prior to the spraying and a second temperature sensed after the spraying within the molding cycle in which the first temperature was sensed. , to control the operation of the cooling unit.

A spray device according to one aspect of the present disclosure includes a spray device main body and a spray control section. The spray device main body sprays toward the mold before mold closing in each molding cycle when molding cycles including mold closing, injection and mold opening are repeated. The spray control section controls the main body of the spray device based on a signal from a sensor that detects the temperature of the mold. The spray control is based on a temperature difference between a first temperature sensed by the sensor prior to the spraying and a second temperature sensed after the spraying within the molding cycle in which the first temperature was sensed. control the operation of the spray device body during subsequent molding cycles.

According to the above configuration, it is possible to improve the accuracy in controlling the temperature of the mold.

1 is a side view showing the configuration of a die casting machine according to an embodiment of the present disclosure; FIG. FIG. 2 is a schematic diagram showing an example of a configuration related to a cooling section of the die casting machine of FIG. 1; FIG. 2 is a schematic diagram showing another example of the configuration of the cooling section of the die casting machine of FIG. 1; 2 is a flowchart for explaining the operation of the die casting machine of FIG. 1; FIGS. 5(a) and 5(b) are timing charts showing one example and another example of a method for adjusting the amount of refrigerant supplied. 6(a) and 6(b) are timing charts showing one example and another example of a method for adjusting the supply amount of the release agent.

Below, first, an outline of a die casting machine according to an embodiment of the present disclosure will be described, and then details of the die casting machine will be described.

(Overview of die casting machine)
FIG. 1 is a side view (partly including a cross-sectional view) showing the configuration of a die casting machine 1 according to an embodiment of the present disclosure. FIG. 1 is provided with an orthogonal coordinate system xyz for convenience. The z direction is the vertical direction and the +z side is upward.

The die casting machine 1 holds a mold 101. The mold 101 includes, for example, a fixed mold 103 and a movable mold 105 . The die casting machine 1 brings the movable die 105 closer to the stationary die 103 and brings it into contact with the fixed die 103 as indicated by the chain double-dashed line in FIG. 1 (the die is closed). Thereby, a cavity Ca having a shape similar to that of a molded product (in other words, a die-cast product or product) is formed between the fixed mold 103 and the movable mold 105 . The die casting machine 1, for example, fills the cavity Ca with an uncured metal material (performs injection). The metal material filled in the cavity Ca is solidified by the mold 101 depriving it of heat. Thereby, a molded product is produced. After that, the die casting machine 1 separates the movable mold 105 from the fixed mold 103 (performs mold opening) in order to take out the molded product. The die casting machine 1 repeats, for example, a molding cycle in which the mold closing, injection and mold opening described above are performed in order.

In each molding cycle, before the molds are closed, a mold release agent or the like is sprayed against the opposing surfaces of the fixed mold 103 and the movable mold 105 . The release agent forms, for example, a film on the surface of the mold 101 and intervenes between the surface of the mold 101 and the metal material filled in the mold 101 . The mold release agent reduces the probability of occurrence of seizure in which the metal material adheres to the mold 101, and reduces the resistance (mold release resistance) when the molded product is peeled off from the mold 101. contribute to The mold release agent can also help cool the mold 101, which has increased in temperature in the previous molding cycle.

FIG. 4 is a flowchart for explaining the operation of the die casting machine 1.

As described above, the die casting machine 1 repeats the molding cycle MC. In each molding cycle MC, for example, spraying (step ST1), mold closing (step ST2), injection (step ST3) and mold opening (step ST4) are sequentially performed. The mold 101 is cooled at an appropriate time by a cooling section 13 (described later) within the molding cycle MC. For example, the cooling operation by the cooling unit 13 includes spraying. Also, cooling operations other than spraying may be performed during the period of spraying.

In this embodiment, the die casting machine 1 detects, for example, the temperature of the mold 101 before spraying and the temperature of the mold 101 after spraying in each molding cycle (steps ST11 and ST12). The former temperature may be called "first temperature" or "first temperature D1", and the latter temperature may be called "second temperature" or "second temperature D2".

The difference between the first temperature and the second temperature in one (same) molding cycle serves as an index value for quantitatively evaluating the cooling effect of the mold 101 by the cooling unit 13 . Therefore, the die casting machine 1 controls the operation of the cooling section 13 based on the difference between the first temperature and the second temperature. In FIG. 4, the molding cycle detected these temperatures based on the first and second temperatures, as indicated by the arrows extending from the first temperature D1 and the second temperature D2 and the control command (command D3). The manner in which the spray in the next molding cycle is controlled is exemplified.

As described above, in the present embodiment, the die casting machine 1 operates the cooling unit 13 thereafter (for example, in the next molding cycle) based on the difference between the first temperature and the second temperature in the same molding cycle. Control. Therefore, for example, it is possible to quantitatively grasp the cooling effect of the cooling unit 13 and specify the operation state of the cooling unit 13 necessary to obtain the target temperature. From another point of view, the operating state of the cooling part 13 is, for example, an operation amount or a manipulated variable of the cooling part 13 (a value of a parameter such as a gain from another point of view), or a physical quantity related to cooling. In this way, the accuracy of controlling the temperature of the mold 101 is improved. Generally, the amount of decrease in temperature of the mold 101 is large when spraying is being performed. Therefore, by controlling the operation of the cooling unit 13 based on the first temperature and the second temperature measured before and after spraying, the accuracy of controlling the temperature of the mold 101 is further improved.

(details of die casting machine)
Here, the die casting machine 1 will be described in the following order.
・Overall configuration of die casting machine 1 (Fig. 1)
・Cooling unit 13 for cooling the mold 101 (Fig. 2 or Fig. 3)
- A temperature sensor 59 for detecting the temperature of the mold 101 (Fig. 2 or Fig. 3)
・Control of the operation of the cooling unit 13 based on the first temperature D1 and the second temperature D2 (FIGS. 4 to 6B)
・Summary of embodiment

(Overall configuration of die casting machine)
As described above, the die casting machine 1 shown in FIG. 1 injects an uncured metal material into the space (including the cavity Ca) formed by the mold 101 . The uncured state is, for example, a liquid state or a solid-liquid coexisting state. The solid-liquid coexistence state is a semi-solid state in which solidification has progressed from a liquid state, or a semi-molten state in which melting has progressed from a solid state. Metals are, for example, aluminum alloys, zinc alloys or magnesium alloys. In addition, hereinafter, expressions may be made on the premise that the uncured metal material is molten metal (liquid metal material).

As described above, the mold 101 includes, for example, a fixed mold 103 and a movable mold 105. In the drawings of the present disclosure, for convenience, the cross section of the fixed mold 103 or the movable mold 105 is indicated by one type of hatching. However, each mold may be of a direct carving type that is integrally formed as a whole, or may be of a nesting type that is configured by inserting a nest into a main mold. Moreover, the mold 101 may have a fixed core fixed to the fixed mold 103 or the movable mold 105 and/or a movable core sandwiched between the fixed mold 103 and the movable mold 105 .

The die casting machine 1 has a cooling section 13 that cools the mold 101 . The cooling section 13 includes a spray device 15 that sprays the mold 101 .

Of the parts that mechanically operate the die casting machine 1, the parts excluding the cooling part 13 are called the machine main body 3. The machine main body 3 includes, for example, a mold clamping device 7 for opening and closing the mold 101 and for clamping the mold, an injection device 9 for injecting molten metal into the mold 101, and a fixed mold 103 or a movable mold 105 (FIG. 1). has an extruder 11 for extruding from a moving die 105).

The die casting machine 1 also has a control device 5 (FIG. 2 or 3 described later) that controls the machine main body 3 and the cooling section 13 . The control device 5 may be regarded as a component separate from the machine body 3, the cooling section 13, or the spray device 15, or may be regarded as a component of the machine body 3, the cooling section 13, or the spray device 15. . In the description of the present disclosure, for the sake of convenience, the former may be used and the latter may be used.

The configuration and operation of the machine body 3 (for example, the mold clamping device 7, the injection device 9, and the extrusion device 11) may be in various modes, and may be a known configuration. Also, the cooling unit 13 and the spray device 15 may be configured in various manners and known configurations, except for the portions related to their control.

For example, the mold clamping device 7 may perform mold opening/closing and mold clamping using a toggle mechanism (example in FIG. 1), or may not have a toggle mechanism. In the latter aspect, mold opening and closing and mold clamping may be performed by separate drive sources. Further, for example, the drive system of the mold clamping device 7 may be an electric system, a hydraulic system (hydraulic system), or a hybrid system combining these.

The injection device 9 may be, for example, one for a cold chamber machine (example in FIG. 1), one for a hot chamber machine, or a hybrid type in which both are combined. may be Further, for example, the drive system of the injection device 9 may be an electric system, a hydraulic system (hydraulic system), or a hybrid system combining these.

The extrusion device 11 may, for example, extrude a molded product from a movable mold 105 (example in FIG. 1) or may extrude a molded product from a fixed mold 103. Further, for example, the extrusion device 11 may have an electric or hydraulic (hydraulic) drive source, or may utilize mold opening by the mold clamping device 7 (without a drive source). ).

The control device 5 may be configured by a computer, for example. The computer includes, for example, a CPU (central processing unit), a ROM (read only memory), a RAM (random access memory), and an external storage device (not shown). Various functional units (described later) that perform control and the like are constructed by the CPU executing programs stored in the ROM and/or the external storage device. Note that the control device 5 may include a logic circuit that performs only certain processing.

(Structure of cooling unit)
FIG. 2 is a schematic diagram showing a cooling section 13A as a specific example of the cooling section 13. As shown in FIG. FIG. 3 is a schematic diagram showing a cooling section 13B as another specific example of the cooling section 13. As shown in FIG.

It should be noted that hereinafter, A may be added to the reference numerals of the constituent elements of the cooling section 13A, and B may be attached to the reference numerals of the constituent elements of the cooling section 13B. In addition, without distinguishing the constituent elements to which A or B is added to the reference numerals, the constituent elements may be referred to by omitting A and B (see also FIG. 1 for the reference numerals in this case).

The cooling unit 13, for example, in addition to the spray device 15 (15A or 15B), is supplied to the flow path 107 provided in the mold 101 (the fixed mold 103 and/or the movable mold 105). It has an internal cooling device 17 (17A or 17B) that regulates the flow. The cooling unit 13 may be regarded as having the controller 5 (or part thereof) as described above.

Here, the constituent elements of the cooling unit 13 will be described in the following order.
・Spray device 15
- Flow path 107 and internal cooling device 17
A control unit that controls the cooling unit 13

(spray device)
The spray device 15 atomizes the liquid, for example, and sprays it onto the mold 101 . The liquid is, for example, a release agent and/or water. In the following description, for the sake of convenience, only the release agent is taken as an example of the liquid. Various known release agents may be used, for example, they may be water-soluble or oil-based. A water-soluble release agent (that is, a release agent containing water) has a higher cooling effect than an oil-based release agent. The release agent may be ejected as it is, or may be diluted with water or the like before being ejected, or may be diluted with water or the like ejected at the same time as the original solution after ejection. The spray device 15 may not collect the spouted release agent, or may collect and reuse it.

The configuration of the spray device 15 may have various configurations, as described above, except for the configuration related to its control, and may have a known configuration, for example. For example, the spray device 15 has one or more (a plurality in the illustrated example) nozzles 19 (19A or 19B) for ejecting the mold release agent toward the mold 101 . The spray device 15 may move the nozzle 19 into and out of the space between the fixed mold 103 and the movable mold 105 which are opened (examples of FIGS. 2 and 3), or may The nozzle 19 may be fixed. For the sake of convenience, the former mode will be referred to as an "insertion type".

The surface of the stationary mold 103 or the movable mold 105 to which the release agent is to be applied (for example, the surface that becomes the inner surface of the cavity Ca) is referred to as the coated surface 109 . The insertion-type spray device 15, for example, sprays a mold release onto the entire surface 109 to be coated from a plurality of nozzles 19 stopped at predetermined positions in the space between the fixed mold 103 and the movable mold 105 which are opened. Alternatively, one or more nozzles 19 are sequentially moved to a plurality of divided areas of the surface 109 to be coated, and the release agent is ejected to the entire surface 109 to be coated. A release agent may be applied. In the latter aspect, the movement of the nozzle 19 and/or ejection of the release agent may be performed continuously or intermittently.

The spray device 15 illustrated in FIGS. 1 to 3 is of an insertion type, and includes, for example, a head 21 (21A or 21B) including a plurality of nozzles 19 and a driving device 23 (23A or 21B) for moving the head 21. 23B). Moreover, as shown in FIGS. 2 and 3, the spray device 15 has a supply device 27 for supplying the release agent to the head 21 (in other words, the nozzle 19).

The head 21 has, for example, a base portion 25 (25A or 25B) that holds the plurality of nozzles 19 in addition to the plurality of nozzles 19 . The base 25 is held by the driving device 23, for example. Further, the base 25 has a flow channel inside, although not shown, and the flow channel connects the supply device 27 and the nozzle 19 .

In FIG. 2, the head 21A is illustrated as having a plurality of nozzles 19A each made up of a relatively long pipe (eg, copper pipe). Each nozzle 19A can adjust the position and orientation of its tip (discharge port) by, for example, bending so as to cause plastic deformation. The plurality of nozzles 19A, for example, extends from one surface (lower surface in the illustrated example) of the base 25A. Note that the head 21A is illustrated as the head 21 in FIG.

FIG. 3 illustrates the head 21B having a plurality of relatively short nozzles 19B. The plurality of nozzles 19B are provided on two surfaces of the base 25B facing the fixed mold 103 or the movable mold 105, and generally spray the release agent from the two surfaces toward the fixed mold 103 or the movable mold 105. Dispense. The plurality of nozzles 19B may be changeable in discharge direction by changing the orientation with respect to the base 25B, or may not be changeable.

The plurality of nozzles 19 (19A or 19B) may have the same or different ejection amounts of the release agent. Further, the ejection amount of the releasing agent may be uniformly controlled from the plurality of nozzles 19, or may be controlled individually. Any of the nozzle 19 , the base 25 and the supply device 27 may be provided with a configuration for making the discharge amounts different from each other or for controlling the discharge amounts individually.

The nozzle 19 (19A or 19B) may or may not be detachable from the base 25. Although not shown, the base 25 (25A and 25B) holds a first portion held by the driving device 23 and connected to the supply device 27, and the nozzle 19. It may be configured to have a detachable second portion, or may not be configured as such.

Since FIGS. 2 and 3 are schematic diagrams, the release agent is simultaneously applied only to a part of the coated surface 109 of the mold 101 . However, the

heads

21A and 21B may be used in such a manner as to spray the release agent onto the entire coating surface 109 of the mold 101 at a predetermined position, or may be used to sequentially separate a plurality of divided areas of the coating surface 109. It may be used in a mode of spraying a stencil agent.

The driving device 23 is capable of moving the head 21 at least in the direction of putting it in and out between the fixed mold 103 and the movable mold 105 (vertical direction in the illustrated example). Further, the driving device 23 may be capable of moving the head 21 in the direction in which the fixed mold 103 and the movable mold 105 face each other, or in a direction intersecting the direction of insertion/removal and the direction of facing (for example, in FIG. 1). x direction)).

The drive device 23 may have any specific configuration for realizing the movement of the head 21 as described above. For example, the driving device 23 may be a vertically articulated robot having a rotating arm (example in FIG. 1), or may be an orthogonal coordinate robot that translates a slide axis. The drive system of the drive device 23 is, for example, an electric type, and FIGS. 2 and 3 schematically show an electric motor (reference numerals omitted) as the drive device 23 . The driving device 23 is installed, for example, on the upper surface of a die plate (not numbered) that holds the fixed mold 103 of the mold clamping device 7 .

For example, the supply device 27 supplies air to the head 21 (base portion 25) in parallel with the release agent. In the base portion 25, a release agent channel and an air channel are formed. The release agent and air are mixed at an appropriate position and atomized, and sprayed onto the coating surface 109 of the mold 101 . The release agent and air may be mixed in the base 25 , in the nozzle 19 , or outside the nozzle 19 .

The supply device 27 may be capable of ejecting only air from the nozzle 19 toward the mold 101 by supplying only air to the head 21 . That is, the spray device 15 may be capable of blowing air. The air blow may be used, for example, to clean the mold 101 before spraying the release agent and/or to remove moisture after spraying the release agent.

The supply device 27 may have any specific configuration for realizing the supply of the releasing agent as described above. In the illustrated example, the supply device 27 has the following components. A tank 29 holding a release agent. A pump 31 for sending air to the tank 29 to pressurize and deliver the release agent in the tank 29 . A valve 33 that controls the flow of released release agent.

The valve 33 may only allow or prohibit the flow of the release agent, or may be a flow control valve capable of controlling the flow rate of the release agent. The flow control valve may or may not be a pressure-compensated flow control valve capable of maintaining a desired flow rate regardless of pressure fluctuations, and may or may not be a servo valve.

Unlike the illustrated example, a pump that sucks and discharges the release agent from the tank 29 may be provided. Also, two or more valves may be provided at appropriate positions. A control valve may be provided to control the pressure of the release agent. In addition to or instead of controlling the valve 33, the presence or absence of the release agent supply or the flow rate may be controlled by controlling the pump. In this case, valve 33 may be omitted.

The supply device 27 may have sensors that detect various physical quantities related to the release agent. For example, the supply device 27 includes a sensor 35 for detecting the flow rate of the release agent, a sensor (not shown) for detecting the pressure of the release agent, a sensor (not shown) for detecting the temperature of the release agent, and/or a release agent. It may have a sensor (not shown) that detects the concentration of the template. Sensor 35 may be used for feedback control of flow, for example, in embodiments in which valve 33 is a flow control valve.

In the supply device 27, a specific configuration for realizing air supply is also arbitrary. In the illustrated example, the supply device 27 has the following components. A pump 37 for delivering air. A valve 39 that controls the flow of delivered air. Moreover, the supply device 27 may have an appropriate sensor such as the sensor 41 for detecting the pressure or flow rate of air.

The valve 39 may only permit or prohibit the flow of air, or may be capable of controlling the pressure or flow rate of air. Unlike the illustrated example, two or more valves may be provided at appropriate locations. In addition to or instead of controlling the valve 39 , the presence or absence of air supply or the pressure (or flow rate) may be controlled by controlling the pump 37 . In this case, valve 39 may be omitted.

(Flow path and internal cooling device)
In FIGS. 2 and 3, only the flow path 107 provided in the moving mold 105 is schematically shown for ease of illustration. In practice, the fixed mold 103 may also be provided with the channel 107 . In addition, the internal cooling device 17 may supply coolant to the channel 107 of the fixed mold 103 and the channel 107 of the movable mold 105 .

The coolant may be liquid, gas, or mist, and may change state as heat is absorbed from the mold 101 . The constituents of the refrigerant are also arbitrary. Examples of liquid refrigerants include water. In the following description, expressions may be based on the premise that the refrigerant is water (liquid). Further, hereinafter, the water supplied to the mold 101 may simply be referred to as cooling water without modification such as being supplied to the mold 101 .

The specific shape, dimensions, etc. of the flow path 107 are arbitrary. For example, the flow path 107 may be of a so-called DC type, a circulation type, a jet type, or a combination thereof. In the DC type, for example, a plurality of flow paths 107 extending in one direction (for example, linearly) in the mold (103 or 105) are provided in parallel to contribute to cooling of the entire mold. In the circulation type, for example, the channel 107 extends so as to surround a local portion of the mold and contributes to cooling of the local portion. In the jet type, for example, the flow path 107 includes a space within a local part of the mold (for example, a fixed core) and a pipe inserted into the space, and the cooling water flowing out from the tip of the pipe into the space is flow to the root side of the pipe cools the local area.

In a mode in which a plurality of channels 107 are provided, the shape and dimensions of the plurality of channels 107 may be the same or different. In addition, two or more and/or all of the plurality of flow paths 107 may be controlled together in permitting/prohibiting the flow of cooling water and/or in flow rate, or may be controlled separately. Separate control may be realized, for example, by providing a plurality of valves 45 (described later) that the internal cooling device 17 has.

The internal cooling device 17 may continuously supply cooling water to the mold 101 over the entire period of each molding cycle, or may intermittently supply cooling water to the mold 101 in each molding cycle. It may be something to do. In the latter aspect, the internal cooling device 17 may or may not supply air to the mold 101 during a period in which cooling water is not supplied. The air may, for example, help purge cooling water within the flow path 107 . For the sake of convenience, the description of air supply is omitted below. The internal cooling device 17 may not recover the cooling water supplied to the mold 101 (example in FIG. 2), or may recover the cooling water supplied to the mold 101 (example in FIG. 3). There may be. In any case, the specific configuration is arbitrary.

The internal cooling device 17A illustrated in FIG. 2 has a pump 43 for sending cooling water and a valve 45 for controlling the flow of the sent cooling water. The pump 43 sucks, for example, cooling water stored in a tank (not shown) and sends it to the flow path 107 . Note that the pump 43 may be factory equipment that supplies cooling water to other machines (for example, other die casting machines). From another point of view, the internal cooling device 17A may not have the pump 43 .

In the internal cooling device 17A, the valve 45 may only allow or prohibit the flow of cooling water, or may be a flow control valve capable of controlling the flow of cooling water. The flow control valve may or may not be a pressure-compensated flow control valve capable of maintaining a desired flow rate regardless of pressure fluctuations, and may or may not be a servo valve.

The internal cooling device 17A may have sensors at appropriate positions that detect various physical quantities related to the cooling water. For example, the internal cooling device 17 includes a sensor 47 that detects the flow rate of cooling water, a sensor (not shown) that detects the pressure of cooling water, and/or a sensor (not shown) that detects the temperature of cooling water. 107 upstream and/or downstream. Sensor 47 may be used for feedback control of flow, for example in embodiments in which valve 45 is a flow control valve.

The internal cooling device 17B illustrated in FIG. 3 has a recovery unit 51 for recovering the cooling water flowing out from the mold 101 in addition to the same configuration as the internal cooling device 17A. The pump 43 sends the cooling water recovered by the recovery unit 51 to the mold 101 . Except for this point, the above description of the internal cooling device 17A may be applied to the internal cooling device 17B.

For example, although not shown, the recovery unit 51 may have one or more tanks for storing cooling water and a device for cooling the cooling water (for example, a heat pump). Part or all of the recovery unit 51 may be factory equipment that also supplies cooling water to other machines (eg, other die casting machines). From another point of view, the internal cooling device 17B may not have the collection section 51 .

As shown in FIG. 3, the internal cooling device 17 (17A or 17B) creates a negative pressure in the channel 107 in addition to or in place of the pump 43 that delivers cooling water to the channel 107 of the mold 101. A pump 49 may be included. Then, cooling water may be caused to flow into the mold 101 by negative pressure. In this case, the possibility that cooling water leaks to the outside of flow path 107 is reduced.

Although not particularly shown, the internal cooling device 17 (17A or 17B) includes a valve that controls the flow on the outflow side of the flow path 107 in addition to or instead of the valve 45 that controls the flow on the inflow side of the flow path 107. may have. This valve may control the presence or absence of supply of cooling water, and may control the flow rate.

(control unit that controls the cooling unit)
As shown in FIGS. 2 and 3, the control device 5 includes, for example, a body control section 53 that controls the machine body 3, a spray control section 55 that controls the spray device 15, and an internal cooling device that controls the internal cooling device 17. and a control unit 57 . These functional units are, for example, configured by the CPU executing programs as described above.

The main body control unit 53, the spray control unit 55, and the internal cooling control unit 57 may be distributed to each other in terms of hardware, or may be integrated. Taking the former example, the main body control section 53 and the internal cooling control section 57 are configured by hardware distributed together with the machine body 3 , while the spray control section 55 is configured by hardware distributed together with the spray device 15 . may be In this case, the spray control section 55 may control the operation of the spray device 15, for example, based on a signal received from the body control section 53 via a cable (not shown).

(temperature sensor)
The temperature sensor 59 (59A or 59B) shown in FIG. 2 or 3 detects, for example, the temperature of the mold 101 before spraying and the temperature of the mold 101 after spraying, as understood from the above description used for detection. The temperature sensor 59 may be regarded as part of the die casting machine 1, the cooling section 13, the spray device 15, or the internal cooling control section 57, or may be regarded as a component separate from these.

The configuration of the temperature sensor 59 may take various forms, for example, it may be similar to a known form. For example, the temperature sensor may be a contact type (eg, thermocouple, thermistor, or resistance temperature detector) or a non-contact type (eg, radiation thermometer). Further, for example, the temperature sensor may directly detect the temperature of the mold 101, or may detect a physical quantity highly correlated with the temperature of the mold 101 (for example, the temperature of the cooling water flowing through the flow path 107). It may be one that detects. The temperature sensor may be a transducer only, or may include a circuit for processing such as amplification in addition to the transducer.

In FIG. 2, as the temperature sensor 59, a contact temperature sensor 59A is illustrated. In FIG. 2, only the temperature sensor 59A for detecting the temperature of the movable mold 105 is shown for ease of illustration, but the temperature sensor 59A for detecting the temperature of the fixed mold 103 may be provided. is.

The position of the temperature sensor 59A is arbitrary. For example, when the mold (103 or 105) is divided into three equal parts in the x-direction, y-direction or z-direction, the temperature sensor 59A may be positioned in any range. The detected value of the temperature sensor 59A may be used as it is, or may be used after being appropriately corrected. In addition, in the description of the present disclosure, the corrected value is also a type of detected value. The same applies to the example of FIG. 3, which will be described later.

Although not shown, one mold (103 or 105) may be provided with two or more temperature sensors 59A. The two or more temperature sensors 59A may be arranged at different positions when viewed in the opposing direction of the fixed mold 103 and the movable mold 105, or may be arranged at different positions when viewed in a direction orthogonal to the opposing direction. may

The detected values of the two or more temperature sensors 59A may be used to identify the representative value of the temperature in the entire mold (103 or 105) or the entire surface to be coated 109, or the temperature in the mold or the surface to be coated 109 It may be used to identify the temperature distribution. Representative values include average values (arithmetic averages) and weighted average values. In specifying the temperature distribution, the detected value of each temperature sensor itself may be used, or in addition to or instead of the detected value itself, a value obtained by interpolation may be used. In addition, in the description of the present disclosure, the value obtained by interpolation is also a type of detection value.

A non-contact temperature sensor 59B is illustrated as the temperature sensor 59 in FIG. In FIG. 3, only the temperature sensor 59B for detecting the temperature of the movable mold 105 is shown for ease of illustration, but the temperature sensor 59B for detecting the temperature of the fixed mold 103 may be provided. is.

More specifically, the temperature sensor 59B is, for example, a thermography that acquires an image of the temperature distribution of the surface 109 to be coated. The temperature sensor 59B may acquire the temperature distribution of the entire coated surface 109 or the temperature distribution of a partial area of the coated surface 109 . Although not particularly shown, a plurality of temperature sensors 59B (or imaging units thereof) that capture images of different regions of the surface to be coated 109 may be provided to obtain the temperature distribution of the entire surface to be coated 109. .

The position of the temperature sensor 59B is arbitrary. For example, the temperature sensor 59B may be positioned above (example shown), laterally or below the mold (103 or 105). Also, the imaging section of the temperature sensor 59B may be fixed, or may be changeable in position and/or orientation. In other words, temperature sensor 59B may or may not be mechanically scannable.

The temperature distribution obtained by the temperature sensor 59B may be used to specify the representative value of the temperature on the surface to be coated 109, or to specify the representative value of the temperature for each region obtained by dividing the surface to be coated 109. or to extract the temperature at a specific location on the coated surface 109 . Representative values include average values (arithmetic averages) and weighted average values.

(Control of operation of cooling unit based on first temperature and second temperature)
As already mentioned, the die casting machine 1 (or alternatively the controller 5, the spray controller 55 or the internal cooling controller 57) determines the temperature difference between the first temperature and the second temperature within the same molding cycle. , controls the operation of the cooling section 13 thereafter (eg in the next molding cycle). More specifically, for example, the control device 5 controls the cooling unit 13 based on the difference between the first temperature and the second temperature, specifying the amount of operation of the cooling unit 13 required to obtain the target temperature, and the like. do. Here, the control of the operation of the cooling unit based on the first temperature and the second temperature will be described in the following order.
Overall control of the operation of the cooling unit based on the first temperature and the second temperature (Fig. 4)
・Example of calculation method of the manipulated variable based on the first temperature and the second temperature ・Specific example of the operation of the cooling unit controlled based on the first temperature and the second temperature (Fig. 5(a) to Fig. 6(b) )

(Overall control of operation of cooling unit based on first temperature and second temperature)
The outline of FIG. 4 has already been described. More details are as follows.

The body control unit 53 controls the mold clamping device 7 to close the mold (step ST2). Although not shown in particular, after the molds are closed (for example, after the movable mold 105 comes into contact with the fixed mold 103), the body control unit 53 activates the mold clamping device 7 so as to clamp the movable mold 105 and the fixed mold 103. Control. Also, although not shown, the body control unit 53 controls, for example, a hot water supply device (not shown) to supply molten metal to the injection device 9 . When the supply of the molten metal is completed, the body control section 53 controls the injection device 9 to inject the molten metal into the cavity Ca (step ST3). When the injected molten metal solidifies, the body control section 53 controls the mold clamping device 7 to open the mold (step ST4). Although not shown, the body control unit 53 controls the extrusion device 11 to extrude the molded product in parallel with the mold opening or after the mold opening. The body control unit 53 repeats such control (molding cycle MC).

The spray control unit 55 controls the spray device 15 at an appropriate time from after opening the mold (usually after extrusion of the molded product) to before closing the mold (usually before the start of closing the mold) to release the mold. A chemical agent is sprayed (step ST1). Although not shown, the spray control unit 55 may sequentially spray release agents (liquids) having different components. In such an embodiment, the spray that serves as the reference for the detection timing of the first temperature D1 and the second temperature D2 may be the spray of any one type of release agent, or the spray of all types of release agents. may be As already mentioned, the spray control unit 55 is designed to clean the mold 101 by blowing air before spraying the mold release agent, and to remove water by blowing air after spraying the mold release agent. A spray device 15 may be controlled.

In addition, the molding cycle MC is defined as a reference point in time (the end point of the previous molding cycle MC and the start point of a new molding cycle MC) of any step among a plurality of steps that are sequentially performed. may In the description of the present disclosure, for the sake of convenience, the molding cycle MC may be expressed with the time point at which the mold opening in step ST4 (or the extrusion step (not shown) for extruding the molded product) is completed as the reference time point.

The control device 5 (from another point of view, the machine main body 3, the spray control unit 55, or the internal cooling control unit 57; hereinafter the same) controls the first temperature D1 and the second temperature D1 detected by the temperature sensor 59, as described above. A temperature D2 is acquired (steps ST11 and ST12). In the description of the present disclosure, the point in time when the temperature is measured by the temperature sensor 59 and the point in time when the control device 5 acquires the information on the measured temperature from the temperature sensor 59 are expressed without particular distinction.

The time point of measurement of the first temperature D1 is before the spray (step ST1), as described above. Whether or not it is "before spraying" may be reasonably determined in light of the above-described effects of the present embodiment. For example, typically, the first temperature D1 may be measured before spraying is started. In this case, the time point at which the first temperature D1 is measured may be immediately before the start of spraying, or may be some time before the start time of spraying. Examples of the latter include, for example, at the start of mold opening, immediately after mold opening, or immediately after extruding the molded product. Besides the typical example, the point of time when spraying is started or immediately after the spraying is started can be mentioned. In other words, the time of measurement of the first temperature D1 may be before at least part of the spraying period, rather than before the entire spraying period.

The second temperature D2 is measured after spraying (step ST1), as described above. Whether it is "after spraying" may be rationally determined in light of the above-described effects of the present embodiment, similarly to "before spraying." For example, typically, the second temperature D2 may be measured after spraying is completed. In this case, the second temperature D2 may be measured immediately after the spray is completed, or may be some time after the spray is completed. Examples of the latter include, for example, when mold closing is started, when mold closing is completed, when mold closing is started, when mold closing is completed, or immediately before injection is started. Other than the typical example, the point at which spraying is completed or immediately before spraying is completed can be mentioned. In other words, the second temperature D2 is measured not after the entire spraying period, but after at least a part of the spraying period (but after the first temperature D1 is measured). It's okay.

As described above. "Before spraying" and "after spraying" may be before and after at least a portion of the period during which spraying occurs. From another point of view, at least part of the period during which the spray is performed may be included in the period from the measurement of the first temperature D1 to the measurement of the second temperature D2. In this case, the above part may be, for example, 30% or more, 50% or more, or 80% or more of the entire period during which spraying is performed, and may be near the start of spraying or near the completion of spraying. or in between.

Further, as understood from the above, the period from the time when the first temperature D1 is measured to the time when the second temperature D2 is measured is the period during which no spray is performed (the period before the start of the spray and/or the completion of the spray). later period). In this case, the ratio of the period during which the spray is being performed (at least a part of the period from the start to the completion of the spray) to the period from when the first temperature D1 is measured to when the second temperature D2 is measured is arbitrary. is. For example, the ratio may be 10% or more, 30% or more, 50% or more, or 80% or more.

As will be described later, the duration of spraying in each molding cycle may change. In such an aspect, the time points at which the first temperature D1 is measured and/or the time points at which the second temperature D2 is measured may or may not be changed.

In the example of FIG. 4, the operation of the spray device 15 is controlled based on the difference between the first temperature D1 and the second temperature D2. However, in addition to or instead of the operation of the spray device 15, the operation of the internal cooling device 17 (or the operation of further cooling means) is controlled based on the difference between the first temperature D1 and the second temperature D2. good too. Just to be sure, in embodiments in which cooling by two or more cooling means is performed at the same time (e.g. during spraying), the operation of one cooling means is adjusted by the difference between the first temperature D1 and the second temperature D2. and the operation of the other cooling means is not adjusted by the difference between the first temperature D1 and the second temperature D2.

In the example of FIG. 4, the first temperature D1 and the second temperature D2 are detected in each molding cycle (in other words, in all molding cycles). Also, the first temperature D1 and the second temperature D2 detected in each molding cycle are used to control the operation of the cooling section 13 in the next molding cycle. In the description of this embodiment, this aspect is basically taken as an example.

However, unlike the illustrated example, for example, the first temperature D1 and the second temperature D2 are detected every two or more predetermined molding cycles (in only one molding cycle among the predetermined number of molding cycles). It may be held on an irregular basis. An example of the latter is, for example, a mode in which detection is performed when some abnormality is detected. Then, for example, the first temperature D1 and the second temperature D2 detected every predetermined number of times or irregularly detected may be used for a plurality of subsequent molding cycles.

Further, for example, unlike the illustrated example, the operation of the cooling unit 13 in subsequent molding cycles is controlled based on the first temperature D1 and the second temperature D2 detected in each of a plurality of molding cycles. good too. For example, based on the first temperature D1 and the second temperature D2 detected in each of a plurality of molding cycles, the average value (moving average value) of the first temperature D1 and the second temperature D2 in the plurality of molding cycles ) may be calculated. Then, based on the average value, the operation of the cooling section 13 in the subsequent molding cycle may be controlled. In this case, for example, the influence of a specific error in the detected temperature that occurs in any one molding cycle on the operation of the cooling unit 13 is reduced.

Also, for example, control of the operation of the cooling unit 13 based on the difference between the first temperature D1 and the second temperature D2 may be started without waiting for the start of the next molding cycle. From another point of view, the change in operation of the cooling unit 13 according to the difference between the first temperature D1 and the second temperature D2 may occur within the molding cycle in which the first temperature D1 and the second temperature D2 are detected. . The operation of the cooling unit 13 controlled based on the difference between the first temperature D1 and the second temperature D2 in this case is assumed to affect the difference between the first temperature D1 and the second temperature D2 in the next molding cycle. you can For example, the changed behavior (in another aspect, the manipulated variable) in response to the difference between the first temperature D1 and the second temperature D2 may be maintained until the spray period of the next molding cycle. A specific example of such an aspect will be described later (FIG. 5(b)).

Control of the operation of the cooling unit 13 based on the difference between the first temperature D1 and the second temperature D2 may be performed in all of a plurality of molding cycles MC (from the first molding cycle to the last molding cycle), or may be performed in a plurality of molding cycles MC. It may be performed only in a part of the molding cycles MC of one molding cycle MC. As an example of the latter, for example, there is a mode in which the above control is performed only when the temperature of the mold 101 is not stable (for example, when a plurality of molding cycles MC are started). Even though the above control is performed in all of a plurality of molding cycles MC, strictly speaking, the above control is not performed in all of the molding cycles MC, depending on the specific aspects of the above control. For example, before the first temperature D1 and the second temperature D2 are first detected in the first molding cycle MC, the operation of the cooling section 13 is controlled based on predetermined initial settings.

(Example of calculation method of manipulated variable based on first temperature and second temperature)
Controlling the operation of the cooling unit 13 based on the difference between the first temperature and the second temperature may be performed in various ways. Hereinafter, control of the operation of the cooling unit 13 based on the difference between the first temperature and the second temperature will be described by exemplifying a relatively simple control mode.

In each molding cycle, when the temperature of the mold 101 is detected and the detected temperature Ta is obtained, the cooling unit 13 is controlled by the manipulated variable u to bring the temperature of the mold 101 to the target temperature Tb. do. At this time, for example, the manipulated variable u may be calculated by the following equation (1).
u=K(Tb−Ta) (1)

It should be noted that K is sometimes called a proportional gain. The manipulated variable u is calculated, for example, once in one molding cycle. Equation (1) can be regarded as an equation representing proportional control in which the period of the molding cycle is the period of feedback.

In this embodiment, the control device 5 sets the proportional gain K based on the difference between the first temperature D1 and the second temperature D2. For example, assume that a first temperature D1 and a second temperature D2 are detected in the same molding cycle, and that the manipulated variable from the detection of the first temperature D1 to the detection of the second temperature D2 is u. In this case, the proportional gain K used in the next molding cycle is calculated by the following equation (2).
K=u/(D2-D1) (2)

Although the same symbols are used for the manipulated variables in formulas (1) and (2), they may be different. From another point of view, the time difference between Ta and Tb and the time difference between D2 and D1 may be the same or different.

The above is an example of a simple mode of controlling the operation of the cooling unit 13 based on the first temperature and the second temperature. Actual control may be performed in various modes other than the above. For example, the proportional gain K may be set based on a map in which D2-D1 (or D1 and D2), the manipulated variable u, and the proportional gain K are associated with each other instead of the above formula. The differential gain and/or the integral gain may be calculated based on the history of past molding cycles or the like. Since there is a correlation between the relationship between the manipulated variable and the cooling effect in the period from the first temperature to the second temperature and the relationship between the manipulated variable and the cooling effect in other periods, The manipulated variable can also be adjusted to achieve the target temperature at the appropriate time.

The above idea can also be applied to the aspect of controlling the temperature of multiple regions (multiple positions from another point of view) of the mold 101 . As previously mentioned, the temperatures of the multiple regions may be detected by multiple contact temperature sensors 59A and/or by thermographic temperature sensors 59B, and may be obtained by interpolation. Further, the temperature control of a plurality of regions is performed by controlling the discharge amounts of the plurality of nozzles 19 of the spray device 15 individually, or by sequentially moving the head 21 of the spray device 15 to a plurality of regions to perform spraying. It may be realized by controlling the amount for each region and/or by individually controlling the amount of cooling water supplied to the plurality of channels 107 .

The following equation (3) shows the determinant when the concept of equations (1) and (2) is extended to temperatures in multiple regions.

Here, ΔT ₁ to ΔT _n indicate temperature changes in the first to n-th regions and correspond to D2-D1 in equation (2) (or Tb-Ta in equation (1)). T ₁ to T _n indicate the temperatures of the first to n-th regions and correspond to D1 in formula (2) (or Ta in formula (1)). u ₁ to u _m indicate the manipulated variables related to the 1st to m-th cooling, and correspond to u in the formula (2) (or the formula (1)).

_A ₁₁ to A _nn (elements of an n×n matrix) are coefficients representing the influence of the first to n-th regions on each other with respect to temperature _. It is a coefficient that indicates the effect on the temperature changes ΔT ₁ to ΔT _n that occur until the second temperature is measured. The coefficient may be obtained based on theory and/or experiments.

B ₁₁ to B _nm (components of the n×m matrix) are coefficients representing the effects of the manipulated variables u ₁ to u _m on the temperature changes ΔT ₁ to ΔT _n , and are represented by equation (2) (or equation (1) ) is equivalent to 1/K. Therefore, the measured T ₁ to T _n and ΔT ₁ to ΔT _n and the manipulated variables u ₁ to u _m at the time of measurement are substituted into the equation (3) in which A ₁₁ to A _nn are preset. , B ₁₁ to B _nm , the manipulated variables u ₁ to u _m for obtaining the target temperature in each of the n regions in the next molding cycle can be obtained.

The magnitude relationship between the number n of multiple regions whose temperature is controlled and the number m of multiple manipulated variables is arbitrary. That is, any of n=m, n<m, and n>m is acceptable. As an example of n=m, there is a mode in which the amount of spray discharged in n regions is used as the manipulated variables u ₁ to u _m . As an example of n<m, there is a mode in which the amount of spray discharge in n regions and the flow rate of cooling water in one or more flow paths 107 are used as the manipulated variables u ₁ to u _m . As an example of n>m, there is a mode in which, as the manipulated variables u ₁ to u _m , the discharge amount of the spray in a region with a smaller number of divisions than the number of divisions of the coated surface 109 for obtaining the temperature distribution is used. When the amount of spray discharge in _one or more regions and the flow rate of cooling water in one or more flow paths 107 are used as the manipulated variables u 1 to u _m , n=m or n<m. may

As can be understood from the above description, the m manipulated variables may be manipulated variables corresponding to different regions of the same type of manipulated variables, or may be different types of manipulated variables. In addition, the different types of operation amounts may be operation amounts of cooling elements that are different from each other, such as the difference between the operation amount of the spray device 15 and the operation amount of the internal cooling device 17, or the time during which the spray is performed. There may be different types of manipulated variables of the same cooling element, such as length and output per unit time in spray.

(Specific example of operation of cooling unit controlled based on first temperature and second temperature)
As mentioned above, the operation of the cooling unit 13 controlled based on the first temperature and the second temperature may be various. From another point of view, the operation of the cooling unit 13 that changes according to the change in the difference between the first temperature and the second temperature or the physical quantity related to the operation may be various.

For example, regarding the operation of the spray device 15, the length of time during which the spray is performed, the discharge amount per unit time in the spray, and/or the temperature of the release agent may be adjusted. Adjusting the length of time and/or the amount dispensed per unit of time may be performed as one type of adjustment of the total amount of release agent dispensed over the duration of the spray. Also, the adjustment of the physical quantity may be performed for only some nozzles 19 of the plurality of nozzles 19 or may be performed for all nozzles 19 . Also, the adjustment amount of the physical quantity may be different for each nozzle 19 or for each of two or more nozzles 19 , or may be common to all nozzles 19 .

Further, for example, regarding the operation of the internal cooling device 17, the length of time that the cooling water is supplied to the mold 101, the flow rate of the cooling water per unit time, and/or the temperature of the cooling water may be adjusted. Adjusting the length of time and the flow rate per unit of time may be done as one type of adjusting the total amount of cooling water supplied to the mold 101 over the duration of the molding cycle. Also, the adjustment of the physical quantity may be performed in only some of the plurality of channels 107 or in all of the channels 107 . Also, the adjustment amount of the physical quantity may be different for each channel 107 or for each of two or more channels 107 , or may be common to all channels 107 .

FIG. 5(a) is a timing chart showing an example of a manner in which the length of time for supplying cooling water to the mold 101 is controlled based on the first temperature and the second temperature.

In this figure, the horizontal axis indicates the elapsed time t. The vertical axis indicates the flow rate Q per unit time of cooling water supplied to the mold 101 (or one or more flow paths 107; the same shall apply hereinafter). On the horizontal axis, time t1 indicates the start time of the molding cycle MC (or the end time of the previous molding cycle MC). Here, for ease of illustration, time t1 is defined as the start time of the period during which the spray is performed (spray period SP), and is defined as the time point when the first temperature D1 is detected. Time t2 is the time when the spray period SP is completed. Also, here, for ease of illustration, time t2 is defined as the time at which the second temperature D2 is detected. In the description of FIG. 5(a), the spray period SP may be read as the detection period DP (reference numeral is shown in FIG. 6(a)) from the detection of the first temperature D1 to the detection of the second temperature D2.

In this example, cooling water is supplied intermittently within each molding cycle. Further, the flow rate Q when cooling water is supplied is set to a constant flow rate Qc. That is, the internal cooling device 17 permits and prohibits the supply of cooling water, but does not control the flow rate Q of the cooling water. Then, the internal cooling device 17 (control device 5 from another point of view) controls the length of time for supplying the cooling water based on the difference between the first temperature D1 and the second temperature D2.

More specifically, in the illustrated example, the internal cooling device 17 starts supplying cooling water within the spray period SP of each molding cycle MC, and resumes supplying cooling water at an appropriate time after the spray period SP. Stop. Examples of the timing for stopping the cooling water include the start of mold opening, the completion of mold opening, and the completion of extruding the molded product. Unlike the illustrated example, the supply of cooling water may be stopped after the next molding cycle is started (but before the supply of cooling water for the next molding cycle is started).

Then, according to the difference between the first temperature and the second temperature, the internal cooling device 17 changes the start point of cooling water supply in the molding cycle following the molding cycle MC in which the first temperature and the second temperature are detected. do. This changes the length of time for which cooling water is supplied. FIG. 5(a) illustrates a situation where the length of time is lengthened from TM1 to TM2. The illustrated example may be interpreted as changing the length of time during which cooling water is supplied within the spray period SP from TM5 to TM6.

FIG. 5(b) is a timing chart showing an example of a mode of controlling the flow rate per unit time of cooling water supplied to the mold 101 based on the first temperature and the second temperature.

In this figure, the horizontal axis (elapsed time t), vertical axis (flow rate Q per unit time), time t1 and time t2 are the same as in FIG. 5(a). Here, too, the spray period SP may be read as a detection period DP (reference symbol in FIG. 6A) from the detection of the first temperature D1 to the detection of the second temperature D2.

In this example, cooling water is continuously supplied throughout the molding cycle MC. Also, the flow rate Q of the cooling water is set to an arbitrary value or a preset value in a plurality of stages. Then, the internal cooling device 17 (control device 5 from another point of view) controls the flow rate Q based on the difference between the first temperature D1 and the second temperature D2.

More specifically, in the illustrated example, the internal cooling device 17 changes the flow rate Q at a predetermined time t3 and maintains the flow rate Q until time t3 of the next molding cycle MC. Time t3 may be any time during the molding cycle MC. For example, the time t3 may be positioned within the period from the completion of the spray period SP to the start of injection (when the temperature of the mold 101 starts rising), or during the start of injection. , after completion of injection. Further, unlike the illustrated example, the time t3 may be the period from the start of the molding cycle MC to the start of spraying in a mode where the spraying is started after the molding cycle MC is started. Furthermore, time t3 may be during the spray period.

Then, according to the difference between the first temperature and the second temperature, the internal cooling device 17 detects the first temperature t3 (the first temperature and the second temperature in the illustrated example) after detecting the first temperature and the second temperature. 2. At time t3) in the same molding cycle as the molding cycle MC in which the temperature is detected, the flow rate Q is changed. FIG. 5(b) illustrates a situation where the flow rate Q increases from Q1 to Q2 and from Q2 to Q3. In the illustrated example, the flow rate Q is changed from the flow rate Q within the spray period SP in the molding cycle in which the first temperature and the second temperature are detected to the flow rate Q within the spray period SP in the next molding cycle. may be taken as

FIG. 6(a) is a timing chart showing an example of a mode of controlling the length of time for spraying based on the first temperature and the second temperature.

In this figure, the horizontal axis indicates the elapsed time t. The vertical axis represents the release agent per unit time discharged from one nozzle 19, two or more nozzles 19, or all nozzles 19 (hereinafter simply referred to as nozzles 19; the same applies to the description of FIG. 6B). It shows the discharge amount q. On the horizontal axis, the time point t1 indicates the start time point of the molding cycle MC, as in FIG. 5A, and is the time point at which the first temperature D1 is detected (the time point at which the detection period DP starts). However, here, unlike FIG. 5A, the time t1 is not set as the start time of the spray period SP. Also, the time t2 is the detection time of the second temperature D2 (end time of the detection period DP), as in FIG. 5(a). However, here, unlike FIG. 5A, the time t2 is not set as the completion time of the spray period SP.

In this example, the ejection amount q of the release agent when spraying is set to be a constant ejection amount qc. That is, the spray device 15 controls the length of time for spraying (TM11 and TM12), but does not control the discharge amount q. Then, the spray device 15 (control device 5 from another point of view) controls the length of time for spraying based on the difference between the first temperature D1 and the second temperature D2.

More specifically, in the illustrated example, the spray device 15 starts and completes spraying within the detection period DP of each molding cycle MC. Then, according to the difference between the first temperature and the second temperature, the spray device 15 determines the length of time (TM11 and TM12 ). This change may be made by changing the play start time point, by changing the play end time point, or by changing both (example shown). FIG. 6(a) illustrates a situation in which the length of time during which the spray is performed increases from TM11 to TM12.

FIG. 6(b) is a timing chart showing an example of a mode of controlling the discharge amount of the release agent per unit time based on the first temperature and the second temperature. In this figure, the horizontal axis (elapsed time t), vertical axis (discharge amount q per unit time), time t1 and time t2 are the same as those in FIG. 6(a).

In this example, the length of time when the spray is performed is a constant length of time TMc. On the other hand, the discharge amount q of the release agent is set to an arbitrary value or a preset value in a plurality of stages. Then, the spray device 15 (from another point of view, the control device 5) detects the first temperature D1 and the second temperature D2 based on the difference between the first temperature D1 and the second temperature D2. Change the discharge amount q in the cycle. The example of FIG. 6B illustrates a situation where the discharge amount increases from q1 to q2. In the illustrated example, the constant time length TMc is shorter than the time length of the detection period DP and falls within the detection period DP. TMc is not limited to such aspects.

As described above, the formula (1) can be regarded as a formula showing control in which feedback is performed in one molding cycle. In order to realize such control, of course, normal feedback control may be performed at a period shorter than the period of the molding cycle. For example, in the example of FIG. 5(b), the flow rate Q1, Q2 or Q3 or the value obtained by multiplying these flow rates by the period of the molding cycle (total amount of cooling water in one molding cycle) is the manipulated variable of equation (1) It may be taken as an example of u. In this case, the operation amount of the valve 45 (different from the operation amount u) is calculated from the deviation between the detected value of the flow rate Q and the flow rate Q1, Q2 or Q3 in a cycle shorter than the cycle of the molding cycle, and is fed back. control may be performed.

(Summary of embodiment)
As described above, the die casting machine 1 according to this embodiment repeats the molding cycle MC, and includes the machine main body 3 , the cooling section 13 and the control device 5 . The machine body 3 sequentially performs mold closing, injection and mold opening within each molding cycle. The cooling unit 13 cools the mold (the mold 101) within each molding cycle. The control device 5 controls the cooling section 13 based on a signal from a sensor (temperature sensor 59 ) that detects the temperature of the mold 101 . The cooling section 13 includes a spray device 15 that sprays toward the mold 101 before mold closing in each molding cycle. The control device 5 detects a first temperature D1 detected by the temperature sensor 59 before spraying, and a second temperature D2 detected by the temperature sensor 59 after spraying within the molding cycle in which the first temperature D1 is detected. The operation of the cooling unit 13 is controlled based on the temperature difference between the .

Therefore, for example, as described above, it is possible to quantitatively grasp the effect of cooling by the cooling unit 13 and specify the operation amount of the cooling unit 13 required to obtain the target temperature. As a result, the accuracy of controlling the temperature of the mold 101 is improved.

The control device 5 may control the operation of the cooling section 13 when spraying is performed in the next molding cycle after each molding cycle based on the difference between the first temperature and the second temperature in each molding cycle.

In this case, for example, the temperature is detected for each molding cycle, and the detection result is immediately reflected in the control of the cooling unit 13, so the accuracy of control is quickly improved. Further, for example, the cooling unit 13 is controlled during the spray period of the next molding cycle based on the temperature during the spray period, so that when the molding cycle is repeated, the correlation between the control content and the temperature detection result is high. As a result, for example, when the molding cycle is repeated, the control tends to be stable, and the accuracy of the control is improved.

In the case of "based on the difference between the first temperature and the second temperature in each molding cycle", as in the case of using the moving average value of the first temperature and the second temperature, the temperature detected in the current molding cycle Along with the first and second temperatures, the first and second temperatures detected in previous molding cycles may be utilized. Also, in the case of "controlling the operation of the cooling unit when spraying is performed in the next molding cycle", as in the example of FIG. may occur in the current molding cycle and its changed state is maintained in the next molding cycle.

The cooling section 13 may include an internal cooling device 17 that supplies coolant (eg, water) into the channel 107 provided in the mold 101 . The control device 5 may adjust the physical quantity of cooling water for subsequent (for example, subsequent molding cycles) based on the difference between the first temperature and the second temperature within the same molding cycle.

The operation of the internal cooling device 17 is easier to change than the spray device 15. Specifically, it is as follows. The operation of the spray device 15 is controlled to take into account not only cooling effects, but also effects such as seizure and/or demolding resistance. On the other hand, the internal cooling device 17 basically does not need to expect other effects from the cooling water. Therefore, the operation of the internal cooling device 17 can be flexibly changed. The temperature is detected based on the period of spraying during which the temperature of the die 101 is greatly lowered, and the internal cooling device 17 adjusts the cooling effect based on the detected temperature. Overall, good temperature control is achieved.

The physical quantity related to the cooling water may include the length of time during which the cooling water is supplied into the flow path 107 in each molding cycle (Fig. 5(a)).

In this case, for example, the need to adjust the flow rate of cooling water is reduced. As a result, for example, the need to provide a flow control valve (or the need to increase the precision of the flow control valve) is reduced, and cost reduction of the internal cooling device 17 is facilitated.

The above physical quantity related to the cooling water may include the flow rate Q per unit time of the cooling water flowing into the flow path 107 during a predetermined period in each molding cycle (Fig. 5(b)). In the example of FIG. 5B, the "predetermined period" is a period corresponding to the time length of the molding cycle from time t3 to the next time t3. The spray period SP or the detection period DP may be regarded as corresponding to the predetermined period.

In this case, for example, the gradient of the temperature change of the mold 101 can be changed by changing the flow rate Q. In other words, the timing at which the gradient of the temperature change of the mold 101 changes can be maintained. Therefore, for example, the probability of an unintended temperature change occurring due to a change in the interrelationship between the timing of cooling by the internal cooling device 17, the timing of temperature change due to the operation of the machine body 3, and the timing of cooling by the spray is reduced. be done.

The control device 5 may adjust the physical quantity related to spraying in subsequent molding cycles based on the difference between the first temperature and the second temperature within the same molding cycle.

In this case, for example, the operation of the cooling means that is highly correlated with the difference between the first temperature and the second temperature is controlled. As a result, for example, as the molding cycle is repeated, the temperature of the mold 101 tends to become stable (within the molding cycle temperature changes tend to be the same between multiple molding cycles.)

The above physical quantity related to spraying may include the time during which spraying is performed in each molding cycle (Fig. 6(a)).

In this case, for example, similarly to the aspect of adjusting the time to supply the cooling water to the flow path 107, the need for providing a flow control valve (or the need for increasing the accuracy of the flow control valve) is reduced, and the spray device 15 cost reduction is facilitated.

The above physical quantity related to the spray may include the amount of liquid ejected by the spray per unit time (discharge amount q) in each molding cycle.

In this case, for example, the timing at which the slope of the temperature change of the mold 101 changes can be maintained in the same manner as in the mode of changing the flow rate Q of the cooling water. As a result, the likelihood of unintended temperature changes occurring, for example, due to changes in interrelationships with the timing of operations of other components that affect temperature changes is reduced.

The die 101 is appropriately replaced by the user of the die casting machine 1. Also, the temperature sensor 59 may be attached to the mold 101 . Therefore, the die casting machine 1 may be regarded as a machine that does not include the mold 101 and the temperature sensor 59 or as a machine that includes the mold 101 and the temperature sensor 59 .

Also, from the die casting machine 1 according to the present embodiment, it is possible to extract a spray device that can be regarded as a device including the spray control unit 55. The spray device may have a main body of the spray device (the spray device 15 when the spray device 15 and the control device 5 are regarded as separate components) and a spray control section 55 . The spray device 15 sprays toward the mold (the mold 101) before mold closing in each molding cycle when the molding cycle including mold closing, injection and mold opening is repeated. The spray controller 55 may control the spray device 15 based on a signal from a sensor (temperature sensor 59 ) that detects the temperature of the mold 101 . Further, the spray control unit 55 controls the first temperature D1 detected by the temperature sensor 59 before spraying and the second temperature D1 detected by the temperature sensor 59 after spraying within the molding cycle in which the first temperature D1 is detected. Based on the temperature difference from temperature D2, the operation of spray device 15 may be controlled in subsequent molding cycles.

A spray device including such a spray control unit 55 may be distributed (or capable of such distribution) separately from the machine main body 3 and the main body control unit 53, or may be distributed separately from the main body 3 and main body control unit 53. It may be one that is not distributed (or impossible). Also, in either aspect, the spray device may or may not include a temperature sensor 59 .

The technology according to the present disclosure is not limited to the above embodiments, and may be implemented in various aspects.

For example, molding machines are not limited to die casting machines. For example, the molding machine may be another metal molding machine, an injection molding machine that molds resin, or a molding machine that molds a material obtained by mixing wood flour with thermoplastic resin or the like. There may be. Further, the molding machine is not limited to horizontal clamping and horizontal injection, and may be, for example, vertical clamping and vertical injection, vertical clamping and horizontal injection, or horizontal clamping and vertical injection.

In the example of FIG. 5(b), the flow rate Q was changed over the entire cycle (period from time t3 to the next time t3) corresponding to the cycle of the molding cycle. However, the flow rate Q may be changed only in part of the cycle (for example, the spray period SP or the detection period DP).

In the embodiment, based on the difference between the first temperature and the second temperature, the operation of the cooling section is adjusted in the molding cycle after the molding cycle in which these temperatures are detected. However, based on the first temperature and the second temperature, the operation of the cooling section may be adjusted only within the molding cycle in which these temperatures are detected.

For example, in the example of FIG. 5(a), the time during which cooling water is supplied within the spray period SP (within the detection period DP) may be the same for a plurality of molding cycles. Then, based on the difference between the first temperature and the second temperature, the time for supplying cooling water may be adjusted only within the molding cycle in which these temperatures are detected. Similarly, in the example of FIG. 5(b), the flow rate Q within the spray period SP (within the detection period DP) may be the same for a plurality of molding cycles. Then, based on the difference between the first temperature and the second temperature, the flow rate Q may be adjusted only within the molding cycle in which these temperatures are detected.

As can be understood from the above, even if the difference between the first temperature and the second temperature changes due to the repetition of the molding cycle, the operation of the cooling unit within the detection period DP (spray period SP) is sufficient for a plurality of moldings. It may be the same from cycle to cycle. In such a mode, for example, when the cooling effect of the cooling unit with respect to the operation amount of the cooling unit changes due to some abnormality or change in the environmental temperature, it is possible to make adjustments according to the change. Further, as in the embodiment, in a mode in which the operation of the cooling unit within the detection period DP of the subsequent molding cycle is adjusted according to the difference between the first temperature and the second temperature, for example, the operation amount of the cooling unit Adjustments can be made to account for the effect of the change on the change in cooling effect of the cooling unit.

1... Die casting machine (molding machine), 3... Machine body, 5... Control device, 13... Cooling part, 15... Spray device, 59... Temperature sensor (sensor), 101... Mold (mold).

Claims

A molding machine that repeats the molding cycle,
a machine body that sequentially performs mold closing, injection and mold opening in each molding cycle;
a cooling section for cooling the mold within each molding cycle;
a control device that controls the cooling unit based on a signal from a sensor that detects the temperature of the mold;
and
The cooling unit includes a spray device that sprays toward the mold before closing the mold in each molding cycle,
The controller controls the temperature difference between a first temperature sensed by the sensor prior to the spraying and a second temperature sensed after the spraying within the molding cycle in which the first temperature was sensed. , a molding machine for controlling the operation of the cooling unit.
2. The molding machine according to claim 1, wherein the control device controls the operation of the cooling section when the spray is performed in the molding cycle following each molding cycle based on the temperature difference within each molding cycle.
the cooling unit includes an internal cooling device that supplies a coolant to a channel provided in the mold;
The molding machine according to claim 1 or 2, wherein the control device adjusts a physical quantity related to the coolant based on the temperature difference.
4. The molding machine according to claim 3, wherein the physical quantity related to the coolant includes a length of time during which the coolant is supplied into the flow path in each molding cycle.
5. The molding machine according to claim 3, wherein the physical quantity related to the refrigerant includes a flow rate per unit time of the refrigerant flowing into the flow path during a predetermined period in each molding cycle.
The molding machine according to any one of claims 1 to 5, wherein the controller adjusts a physical quantity related to the spray based on the temperature difference.
7. The molding machine according to claim 6, wherein the physical quantity related to the spray includes the time during which the spray is performed within each molding cycle.
The molding machine according to claim 6 or 7, wherein the physical quantity related to the spray includes the amount of liquid ejected by the spray per unit time in each molding cycle.
said mold;
the sensor;
The molding machine according to any one of claims 1 to 8, further comprising:
a spray device main body that sprays toward the mold before mold closing in each molding cycle when molding cycles including mold closing, injection and mold opening are repeated;
a spray control unit for controlling the main body of the spray device based on a signal from a sensor that detects the temperature of the mold;
and
The spray control is based on a temperature difference between a first temperature sensed by the sensor prior to the spraying and a second temperature sensed after the spraying within the molding cycle in which the first temperature was sensed. to control the operation of said spray device body within a subsequent molding cycle.