JPH0985387A - Method for cooling die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling method of a die which can adjust a careful cooling at each part of the die and can uniformly cool the die. SOLUTION: Molten metal is injected into a cavity in the die 4 under condition of supplying fine flowing quantity of cooling water into the die 4 from a flow rate adjusting valve 12 through piping 22B from piping 22A connected with each piping through a valve chest 34A of a solenoid directional valve 30. Temp. of the cooling water flowing each opening hole 10, 10A,..., 10F is measured with a temp. sensor and a measured signal is inputted to a control unit and the temp. difference between the supplying hole 10 and each draining hole 10A,..., 10F, is calculated. It is judged whether each temp. difference is in a prescribed range or not, and if any one is out of the prescribed range, the adjustments of the supplying flow rate and the draining flow rate of the cooling water are executed. In such a way, the draining flow rate of each draining hole 10A,..., 10F is controlled so that each temp. difference becomes almost uniformity and each part of the die 4 is made to uniformly and suitably cool.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cooling a mold by flowing a cooling medium such as cooling water or cooling air through a cooling medium passage provided in the mold.

[0002]

2. Description of the Related Art A molding die such as a casting die or an injection molding die is provided with a passage for flowing a cooling medium such as cooling water or cooling air for the purpose of cooling the vicinity of a cavity. In order to obtain a cast product or an injection molded product of excellent quality, it is extremely important to appropriately cool the mold with this cooling medium. As an example of a technique for appropriately cooling the mold, there is a technique described in Japanese Patent Laid-Open No. 2-258139. In this technique, a temperature sensor is provided in the casting die, and a flow rate control valve is provided on the inlet side of the cooling water passage of the casting die. Then, the reference temperature of the mold at each time point during a predetermined casting cycle is compared with the mold temperature measured by the temperature sensor at each time point, and the measured mold temperature is higher than the reference temperature. For example, the flow control valve is opened to increase the cooling water flow rate, and if it is lower than the reference temperature, the flow control valve is closed to reduce the cooling water flow rate. In this way, the mold temperature is controlled so that the mold temperature changes approximately equal to the reference temperature of the mold at each time point of a predetermined casting cycle.

[0003]

However, the cooling water passage of the mold in the prior art has only one cooling water discharge port for one cooling water supply port. Therefore, no matter how much the cooling water flow rate is adjusted by the flow rate control valve, it is not possible to finely adjust the cooling of each part of the mold between the cooling water supply port and the discharge port. Therefore, it is difficult to uniformly cool the mold, particularly when the temperature of each part of the mold between the cooling water supply port and the discharge port varies due to the shape of the cavity or the like. As a result, there is a problem that the quality of the molded product deteriorates and, in an extreme case, seizure or the like of the product occurs in a portion where cooling is insufficient. Therefore, the inventions according to claim 1 and claim 2 of the present application provide a mold cooling method capable of uniformly cooling the mold by enabling fine adjustment of cooling in each part of the mold. The purpose is to Further, the invention according to claim 3 and claim 4 of the present application has an object to provide a mold cooling method capable of surely cooling the mold uniformly and to an optimum degree.

[0004]

In order to solve the above problems, therefore, in the invention according to claim 1, in the cooling medium passage of the mold, two or more coolings are provided for one cooling medium supply port. A medium discharge port is provided, and a flow rate adjustment valve is provided at each of the supply port and the two or more discharge ports, and the temperature of the cooling medium at the two or more discharge ports is measured. A mold cooling method is created, which is characterized in that the opening of each of the flow rate adjusting valves is adjusted so as to reduce the variation in temperature. Here, the "cooling medium" includes various cooling media such as cooling water, cooling oil, and cooling air. Further, the "cooling medium passage of the die" means a passage of a cooling medium for cooling the die,
Various types of cooling pipes such as cooling pipes provided in close contact with the mold are included, including cooling holes formed in the mold. Thus, in the mold cooling method of the present invention,
Two or more cooling medium discharge ports and flow rate adjustment valves are provided for one cooling medium supply port, and the opening of each flow rate adjustment valve is adjusted so that the measured temperature of the cooling medium at each discharge port becomes uniform. are doing. As a result, each part of the mold in the vicinity of the cooling medium passage leading to each discharge port can be cooled uniformly. In this way, a method for cooling a mold can be achieved in which the cooling of each part of the mold can be finely adjusted and the mold can be cooled uniformly.

According to a second aspect of the present invention, there is provided the method of cooling a mold according to the first aspect, wherein the supply amount of the cooling medium is set to a predetermined maximum amount and the temperature of the two or more temperatures is If the variation does not fall within the predetermined size, the cooling medium is supplied from the discharge port farthest from the supply port among the two or more discharge ports, and from the other discharge port and the supply port. A method for cooling a mold has been created, in which the supply direction of the cooling medium is changed so as to discharge the cooling medium. Thus, if the measured temperature of the cooling medium at each outlet is not uniform even if the supply amount of the cooling medium is set to a predetermined maximum amount, the temperature difference of the mold along the supply direction of the cooling medium causes the cooling medium It is considered to be larger than the cooling capacity of. Therefore, by changing the supply direction of the cooling medium, the cooling medium is supplied from the discharge port farthest from the supply port of the two or more discharge ports, and the cooling medium is discharged from the other discharge port and the previous supply port. To do. As a result, the cooling medium can be supplied from the side of the mold whose temperature is high, and the measured temperature of the cooling medium at each outlet can be made uniform by adjusting the opening of the flow rate adjustment valve at the inlet and each outlet. Can be. In this way, a method for cooling a mold can be achieved in which the cooling of each part of the mold can be finely adjusted and the mold can be cooled uniformly.

In order to solve the above problems, in the invention according to claim 3, two or more cooling medium discharge ports are provided for one cooling medium supply port in the cooling medium passage of the mold. A flow rate adjusting valve is provided at each of the supply port and the two or more discharge ports to measure the temperature difference between the temperature of the cooling medium at the supply port and the temperature of the cooling medium at the two or more discharge ports. Then, a method of cooling a mold is created, in which the opening degree of each of the flow rate adjusting valves is adjusted so that the values of two or more measured temperature differences are all within a predetermined range. . As described above, in the present invention, each flow rate adjustment is performed so that the temperature difference between the temperature of the cooling medium at the supply port and the temperature of the cooling medium at the supply port falls within a predetermined range, rather than simply making the measured temperature of the cooling medium at each discharge port uniform. The valve opening is being adjusted. These temperature differences are numerical values that directly reflect the degree to which the mold is cooled. Therefore, by this, not only the temperature of the mold in the vicinity of each discharge port can be made uniform, but also the degree of cooling of the mold can be reliably maintained within an optimum range. In this way, a mold cooling method is provided which can surely cool the mold uniformly and optimally.

According to a fourth aspect of the present invention, there is provided the method of cooling a mold according to the third aspect, wherein the temperature difference of two or more is set even if the supply amount of the cooling medium is a predetermined maximum amount. When not all of the values of the above fall within the predetermined range, the cooling medium is supplied from the discharge port farthest from the supply port among the two or more discharge ports, and the other discharge port and the supply port. A method for cooling a mold is created, in which the supply direction of the cooling medium is changed so as to discharge the cooling medium from the above. In this way, if the temperature difference between the measured temperature of the cooling medium at each discharge port and the temperature of the cooling medium at the supply port does not fall within the predetermined range even if the supply amount of the cooling medium is set to a predetermined maximum amount, It is considered that the temperature gradient of the mold along the supply direction of the cooling medium is larger than the cooling capacity of the cooling medium. Therefore, by changing the supply direction of the cooling medium, the cooling medium is supplied from the discharge port farthest from the supply port of the two or more discharge ports, and the cooling medium is discharged from the other discharge port and the previous supply port. To do. As a result, the cooling medium can be supplied from the side of the mold having a higher temperature, and the temperature difference can be controlled within a predetermined range by adjusting the openings of the flow rate adjusting valves of the supply port and the discharge ports. Can be In this way, a mold cooling method is provided which can surely cool the mold uniformly and optimally.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Here, as an embodiment of the present invention, a hole which is a part of a cooling medium passage is linearly formed in a die, and the linear cooling medium passage is formed from the middle thereof. A hole serving as a branched cooling medium passage is bored, one opening of the linear cooling medium passage serves as a cooling medium supply port, and the other of the linear cooling medium passage and the branched cooling medium passage The opening serves as a cooling medium discharge port, and a flow rate adjusting valve is provided at each of the discharge ports to measure the temperature difference between the temperature of the cooling medium at the supply port and the temperature of the cooling medium at the discharge port. It is desirable that the mold cooling method is characterized by adjusting the opening degree of each of the flow rate adjusting valves so that the variation of each measured temperature difference becomes small. In this way, by providing the cooling medium hole branched from the middle of the linear cooling medium hole and adjusting the flow rate of the cooling medium in the hole, the mold temperature around each cooling medium hole is made uniform. Therefore, it is possible to reduce the temperature difference between the respective parts of the mold along the linear cooling medium passage. This makes it possible to finely adjust the cooling in each part of the mold and to provide a mold cooling method capable of uniformly cooling the mold.

Further, according to an embodiment of the present invention, a hole which is a part of the cooling medium passage is linearly formed in the die,
A hole serving as a cooling medium passage branched from the middle of the linear cooling medium passage is bored, and one opening of the linear cooling medium passage serves as a cooling medium supply port, and the linear cooling medium passage Of the other side and the branch of the branched cooling medium passage are used as outlets for the cooling medium, and a flow rate adjusting valve is provided for each of the outlets, and the temperature of the cooling medium at the supply port and the temperature of the cooling medium at the outlet are Each temperature difference from the temperature is measured, the opening of each flow rate adjusting valve is adjusted so that the variation in each measured temperature difference is reduced, and the supply amount of the cooling medium is set to a predetermined maximum. If the variation in each temperature difference does not fall within a predetermined range even in a large amount, the cooling medium is supplied from the other opening of the linear cooling medium passage, and the linear cooling medium passage Open one And it is desirable that the method of cooling the mold, characterized in that to change the feed direction of the cooling medium to discharge the cooling medium from the opening of the branched cooling medium passage. Thereby, the cooling medium can be supplied from the side of the mold having a high temperature, and by adjusting the opening of the flow rate adjusting valve of the supply port and each discharge port,
The measured temperature of the cooling medium at each outlet can be made uniform. In this way, a method for cooling a mold can be achieved in which the cooling of each part of the mold can be finely adjusted and the mold can be cooled uniformly.

According to another embodiment of the present invention, two or more holes, which are a part of the cooling medium passage, are linearly formed in the die, and the two or more linear cooling medium passages are provided on the way. A hole to be a cooling medium passage branched from each of the two is formed, and one opening of the two or more linear cooling medium passages is used as a supply port of the cooling medium. On the other hand, the opening of the branched cooling medium passage is used as a cooling medium discharge port, and each of the discharge ports is provided with a flow rate adjusting valve to control the temperature of the cooling medium at the supply port and the cooling medium at the discharge port. Each temperature difference from the temperature is measured, and the opening degree of each of the flow rate adjusting valves is adjusted for each of the two or more linear cooling medium passages so that the dispersion of each measured temperature difference becomes small. Characterized by It is desirable that the method of cooling the mold. In this way, a plurality of cooling medium supply mechanisms having cooling medium passages branched from the linear cooling medium passages are provided in the mold, and the opening degree of each flow rate adjusting valve is adjusted for each of the cooling water supply mechanisms of a plurality of systems. By performing independently, finer, more uniform, and proper cooling can be performed over the entire mold. In particular, even if the mold is large, there is an advantage that uniform cooling can be realized over the entire mold.

Further, as another embodiment of the present invention, in the cooling medium passage of the mold, two or more cooling medium discharge ports are provided for one cooling medium supply port, and the supply port and the two or more cooling medium discharge ports are provided. A flow rate adjustment valve is provided at each of the outlets of
The temperature difference between the temperature of the cooling medium at the supply port and the temperature of the cooling medium at the two or more discharge ports is measured, and the values of the two or more temperature differences measured are all within a predetermined range. Even if the opening degree of each of the flow rate adjusting valves is adjusted so that the cooling medium supply amount is set to a predetermined maximum amount, all of the two or more temperature difference values do not fall within the predetermined range. In this case, the cooling medium is supplied from the outlet having the highest temperature of the cooling medium among the two or more outlets, and the cooling medium is discharged from the other outlet and the inlet. It is desirable to use a mold cooling method characterized by changing the supply direction of. This makes it possible to reliably supply the cooling medium from the side with the higher mold temperature regardless of the temperature distribution of the mold, and to adjust the opening of the flow rate adjustment valve at the supply port and each discharge port. Thus, the measured temperature of the cooling medium at each outlet can be made uniform.

[0012]

【Example】

First Embodiment Next, a first embodiment embodying the present invention will be described with reference to FIGS. First, a mold cooling device used in the mold cooling method of this embodiment will be described with reference to FIG. 1A and 1B are views showing the configuration of a mold cooling device 2 used in this embodiment. FIG. 1A is a plan view of a mold part, and FIG. 1B is a front sectional view of the mold part and the whole. It is a schematic diagram which shows a structure. As shown in FIG. 1, a straight cooling water passage 6 is bored horizontally in the mold 4 cooled by the mold cooling device 2. From this straight cooling water passage 6, as shown in FIG.
Five cooling water passages 6A, 6B, 6C, 6D, 6E are provided by branching in the horizontal direction. Further, FIG. 1 (B)
As shown in, each cooling water passage 6A, 6B, 6C, 6
Cooling water passages 8A, 8B, 8C, 8D, and 8E are formed to extend from the tips of D and 6E directly downward and open to the bottom surface of the mold 4.

Openings 1 at both ends of a linear cooling water passage 6
Flow rate adjusting valves 12 and 12F are attached to 0 and 10F, respectively, and cooling water passages 8A, 8B, 8C, 8D,
8E openings 10A, 10B, 10C, 10D, 10
E is a flow control valve 12A, 12B, 12C, 1 respectively.
2D and 12E are attached. Outside the mold 4, a cooling water supply mechanism for supplying cooling water to these cooling water passages is provided. The cooling water pressure pump 20 is connected to one of the input side ports of the electromagnetic directional valve 30 by a pipe 22A, and the pipes 22B and 22C are connected to the two output side ports of the electromagnetic directional valve 30, respectively. The pipes 22B and 22C are connected to the flow rate adjusting valves 12 and 12, respectively.
Connected to F. The cooling water tank 26 is connected to the other of the input side ports of the electromagnetic directional valve 30 by a pipe 22D.
Is connected. A pipe 24 is provided in the middle of this pipe 22D.
A is connected, and the pipe 24A is further connected to the pipe 24
B, 24C, 24D and 24E are branched. These pipes 24A, 24B, 24C, 24D and 24E are respectively connected to the flow rate adjusting valves 12A, 12B, 12C, 12D and
12E.

The electromagnetic directional valve 30 has three valve chambers 34A, 34A
B and 34C are provided, and when the electromagnetic solenoid 32 is inoperative, the valve chamber 34A is connected to each pipe by the urging force of the spring 36. That is, the pipes 22A and 22B and the pipes 22C and 22D are in communication with each other, and the pressure cooling water is supplied to the flow rate adjusting valve 12 via the pipes 22A and 22B. The supplied cooling water is branched from the cooling water passage 6 to the cooling water passages 6A, 6B, 6C, 6D, 6E, and the cooling water flowing in the cooling water passage 6 flows in the pipe 22C through the flow rate adjusting valve 12F. Is returned to the cooling water tank 26 through the pipe 22D through the valve chamber 34A of the electromagnetic directional valve 30. On the other hand, the cooling water that has flowed into the cooling water passages 6A, 6B, 6C, 6D, 6E is flow rate adjusting valves 12A, 12B, 12C, 12
Piping 24A, 24B, 24C, 24 through D, 12E
It flows in D and 24E. Then, it joins the pipe 24A and is returned to the cooling water tank 26 via the pipe 22D.

When the electromagnetic solenoid 32 is controlled by the control unit (not shown) to have a low excitation force, each valve chamber moves against the urging force of the spring 36, and the central valve chamber 34B is connected to each pipe. The state shown in FIG.
That is, each of the pipes 22A, 22B, 22C and 22D is connected to the port in the closed state and the pipes 22B and 22C are connected.
Is cut off from the cooling water pressure pump 20, so that the cooling water is not supplied to the mold 4. Electromagnetic solenoid 32
Is controlled to a higher exciting force, the valve chamber 34C is connected to each pipe. That is, the pipes 22A and 22
C, the pipes 22B and 22D are in communication with each other, and the pipe 2
The pressure cooling water is supplied to the flow rate adjusting valve 12F via 2A and 22C. The supplied cooling water is branched from the cooling water passage 6 to the cooling water passages 6A, 6B, 6C, 6D, 6E, and the cooling water flowing in the cooling water passage 6 is supplied to the pipe 2 via the flow rate adjusting valve 12.
2B, and is returned to the cooling water tank 26 via the pipe 22D via the valve chamber 34C of the electromagnetic directional valve 30. On the other hand, the cooling water that has flowed into the cooling water passages 6A, 6B, 6C, 6D, 6E is flow rate adjusting valves 12A, 12B, 12C, 12D, 12.
Pipes 24A, 24B, 24C, 24D, 24 through E
It flows through the inside of E, joins the pipe 24A, and is returned to the cooling water tank 26 through the pipe 22D.

Further, each opening 1 of the cooling water passage of the mold 4
0,10A, 10B, 10C, 10D, 10E, 10F
A temperature sensor (not shown) is provided in each. The temperature of the cooling water passing through each opening is measured by these temperature sensors, and the measurement output signal is input to a control unit (not shown). This control unit is a computer system mainly composed of a central processing unit (CPU) and memory devices such as RAM and ROM, and controls the operation of the mold cooling device 2. Each flow rate adjusting valve 12, 1
The adjustment of the openings of 2A, 12B, 12C, 12D, 12E and 12F is performed by a control signal from this control unit. Further, as described above, switching of the electromagnetic directional valve 30 is also performed by sending a control signal from this control unit to the electromagnetic solenoid 32.

Next, the procedure of mold cooling control in the mold cooling device 2 of the present embodiment having such a configuration will be described with reference to FIG. FIG. 2 is a flow chart showing the procedure of cooling control in the mold cooling method of the present embodiment. At the time when control is started in step S10 of FIG. 2, the electromagnetic directional valve 30 of FIG.
4B is connected to each pipe, and each flow rate adjusting valve 12, 12A, 12B, 12C, 12D, 12
The openings of E and 12F are adjusted so that the flow rate is minute. First, the maximum cooling water supply flow rate is determined by limiting the cooling temperature range of the mold (step S12). This cooling temperature range is limited so as not to overcool the mold and adversely affect casting. Then, the solenoid directional valve 3
A valve chamber 34A of 0 is connected to each pipe, and a small amount of cooling water is supplied from the flow rate adjusting valve 12 into the mold 4 through the pipe 22A and the pipe 22B. The supplied cooling water is branched from the cooling water passage 6 into the cooling water passages 6A, ..., 6E and discharged from the flow rate adjusting valves 12A, ..., 12F. In this way, with a minute flow of cooling water flowing in the mold 4, the mold 4
A high-temperature molten metal is injected into a cavity (not shown) therein for casting (step S14).

As a result, the temperature of the mold 4 rises and the temperature of the cooling water flowing in the mold 4 also rises, so that the openings 10, 10A, 10B, 10C, 10D, 10E,
The temperature of the cooling water flowing through 10F is measured by the temperature sensor (step S16). The measurement signal is input to the control unit, and the temperature difference between the supply port 10 and each discharge port 10A, ..., 10F is calculated. Then, it is determined whether or not each temperature difference is within a predetermined range (step S18). That is, the temperature of the cooling water at the supply port 10 is T _0, and the temperatures of the cooling water at the respective discharge ports 10A, ..., 10F are Ta, Tb, Tc, Td, Te,
Assuming Tf, temperature differences ΔTa = Ta−T ₀ , ΔTb = T
b−T ₀ , ΔTc = Tc−T ₀ , ΔTd = Td−T ₀ ,
ΔTe = Te−T ₀ and ΔTf = Tf−T ₀ are calculated. Then, these values ΔTa, ΔTb, ΔTc, ΔT
Ranges T1 to T2 in which d, ΔTe, and ΔTf are predetermined
It is determined whether (T1 <T2). If the temperature differences ΔTa, ..., ΔTf are all above the predetermined value T1 and below T2, the determination in step S18 is Y.
Since ES has occurred and each part of the mold 4 has been uniformly and appropriately cooled, the control is terminated as it is and the cooling is continued (step S20).

On the other hand, the temperature difference ΔTa, ..., ΔTf
If there is a value out of the predetermined range T1 to T2, the determination in step S18 becomes NO, and the supply flow rate and the discharge flow rate of the cooling water are adjusted (step S).
22). Specifically, the opening of the flow rate adjusting valve 12 is increased to increase the supply flow rate of the cooling water, and at the discharge port having a large temperature difference from the temperature T ₀ of the cooling water at the supply port 10, the cooling water amount becomes insufficient. It is considered that the discharge flow rate is increased by increasing the opening of the flow rate adjustment valve. On the contrary, regarding the discharge port having a small temperature difference from the temperature T ₀ of the cooling water of the supply port 10, it is considered that the amount of the cooling water is too large, so the opening degree of the flow rate adjusting valve is reduced to reduce the discharge flow rate. In this way, the temperature difference ΔT
Each of the discharge ports 10 so that a, ..., ΔTf are substantially uniform.
By controlling the discharge flow rate of A, ..., 10F, each part of the mold 4 is uniformly and appropriately cooled. Subsequently, it is determined whether or not the supply flow rate of the cooling water has reached the maximum value determined in step S12 (step S2).
4). If the determination is NO, the process returns to step S16 and the same control is continued.

On the other hand, when the supply flow rate of the cooling water reaches the maximum value, it is considered that cooling cannot be performed uniformly in this supply direction, so the electromagnetic directional valve 30 is switched and the cooling water supply direction is changed. Is reversed (step S2
6). That is, the electromagnetic solenoid 32 of the electromagnetic directional valve 30.
Is excited and the valve chamber 34C is connected to each pipe, and the flow rate adjusting valve 12 passes from the pipe 22A to the pipe 22C.
Cooling water is supplied from F to the mold 4. The supplied cooling water is branched from the cooling water passage 6 into the cooling water passages 6A, ..., 6E and is discharged from the flow rate adjusting valves 12, 12A ,. With the cooling water flowing backward in this manner, the process returns to step S16, and the temperature of the cooling water flowing through each opening is measured. In this case, the discharge ports 10, 10A, ..., 10E with respect to the temperature Tf of the cooling water at the supply port 10F.
The temperature difference of the temperature of the cooling water in is calculated. And
Each temperature difference has a predetermined range T1 to T2 (T1 <T
2) It is determined whether or not it is within (step S18). If all the temperature differences are not less than the predetermined value T1 and not more than T2, the determination in step S18 is YES, and each part of the mold 4 is uniformly and appropriately cooled. Is continued (step S20).

On the other hand, a predetermined range T1 of the temperature difference
If there is a value out of T2, the supply flow rate and the discharge flow rate of the cooling water are adjusted (step S22). Here, the fact that the condition for reversing the supply direction of the cooling water is first satisfied in step S26 means that the temperature difference of the mold along the cooling water passage 6 is larger than the cooling capacity of the cooling water. . Therefore, by reversing the supply direction of the cooling water in step S26, the cooling water is supplied from the side of the opening 10F having a higher mold temperature. Therefore, normally, by repeating the adjustment of the supply flow rate and the discharge flow rate, it is possible to bring each temperature difference into the predetermined range T1 to T2.

In this embodiment, the temperature difference between the temperature of the cooling water at the supply port and the temperature of the cooling water at each discharge port is calculated, and each temperature difference is set in a predetermined temperature range T1 to T2.
It adopts a method to judge whether it is inside or not.
That is, it is determined whether or not the variation in the absolute value of each temperature difference is within a predetermined range, but instead of this,
It is also possible to adopt a method of determining the relative variation of each temperature difference. Specifically, the largest value and the smallest value are extracted from each temperature difference, and if the difference between these two values is less than or equal to a predetermined value, it is determined that uniform cooling is being performed. To do. If the casting conditions such as the molten metal temperature are stable and the water pressure of the supplied cooling water is almost constant, it is sufficient to check the relative variation without taking the absolute value of each temperature difference. Control can be performed. This has the advantage of simplifying the determination calculation process.

Further, it is also possible to adopt a method of judging whether the variation of the temperature of the cooling water at each outlet is within a predetermined range instead of the temperature difference. That is, the highest value and the lowest value of the temperature of the cooling water at each discharge port are extracted, and if the difference between these two values is less than or equal to a predetermined value, then uniform cooling is performed. It is a judgment. It is also possible to adopt a method of determining whether or not the temperature of the cooling water at each outlet is within a predetermined temperature range. By adopting these methods, there is an advantage that the calculation process of the determination is further simplified.

However, in each of the other methods described above, when an abnormal situation occurs such that the temperature of the molten metal becomes too high or the temperature or water pressure of the supplied cooling water changes greatly,
Even if each temperature difference greatly deviates from the normal value, there is a disadvantage that it is determined that appropriate cooling is performed unless the temperature difference or each temperature relatively varies. In order to prevent such a problem, a device for issuing an alarm when the mold temperature, the temperature of the supplied cooling water, or the water pressure becomes an abnormal value may be provided. On the other hand, as in the present embodiment, each temperature difference has a predetermined temperature range T1.
According to the method of determining whether or not the temperature is within T2, the absolute value of the temperature difference is a numerical value that directly reflects the degree of cooling, so that appropriate cooling is performed when such an abnormal situation occurs. There is an advantage that an accurate judgment is always made without being judged as being broken.

Further, in this embodiment, only the opening 10 or 10F is used as the supply port, and the other openings 10A, ...,
10E is always configured as a discharge port, but all the openings 10, 10 are combined by a combination of an electromagnetic directional valve and piping.
It is good also as a structure which can select A, ..., 10F as a supply port. With such a configuration, when the supply direction of the cooling water is changed, the outlet having the highest temperature of the cooling water at the outlet can be selected as the supply outlet.
This makes it possible to reliably supply cooling water from the side with a high mold temperature regardless of the temperature distribution of the mold, and to adjust the opening of the flow rate adjustment valve at the supply port and each discharge port. Thus, the measured temperature of the cooling water at each outlet can be made uniform.

Second Embodiment Next, a second embodiment embodying the present invention will be described with reference to FIG. FIG. 3 is a schematic diagram showing the overall configuration of the mold cooling device 52 used in this embodiment. FIG.
As shown in FIG. 3, in the mold 54 cooled by the mold cooling device 52, three linear cooling water passages 56A,
56B and 56C are provided in the horizontal direction. From these linear cooling water passages 56A, 56B, and 56C, five cooling water passages (not shown) are branched and formed as in the first embodiment. Straight cooling water passage 56
A, 56B and 56C have openings 58A and 58B at one end,
58C has flow rate adjusting valves 62A, 62B, 62C, respectively.
Is attached, and the openings 60A, 60B at the other end are
60C has flow rate adjusting valves 64A, 64B, 64C, respectively.
Is attached. Further, a flow rate adjusting valve is attached to each opening of the branched cooling water passage (not shown).

A cooling water supply mechanism for supplying cooling water to these cooling water passages is provided outside the mold 54.
The cooling water pressure pump 80 includes pipes 72A, 72B, 72C.
Are connected to one of the input side ports of the electromagnetic directional valves 70A, 70B and 70C, respectively. Pipes 68A, 68B and 68C are connected to one of the two output side ports of these electromagnetic directional valves 70A, 70B and 70C, respectively, and the pipes 68A, 68B and 68C are the flow rate adjusting valves 62A, 62B and It is connected to 62C. Further, the other ports on the output side of the electromagnetic directional valves 70A, 70B, 70C are provided with pipes 66A, 66B,
66C is connected, and the pipes 66A, 66B and 66C are connected to the flow rate adjusting valves 64A, 64B and 64C, respectively. A cooling water tank 82 is connected to the other of the input side ports of the electromagnetic directional valves 70A, 70B, 70C by pipes 74A, 74B, 74C. The cooling water tank 82 is also connected to piping (not shown) from each flow rate adjusting valve in a branched cooling water passage. The structures and functions of the electromagnetic directional valves 70A, 70B, 70C are similar to those of the electromagnetic directional valve 30 of the first embodiment. As described above, in the mold cooling device 52 of this embodiment, three cooling water supply mechanisms similar to the cooling water supply mechanism of the first embodiment are provided.

Further, a temperature sensor is provided at each opening 58A, 60A, 58B, 60B, 58C, 60C of the cooling water passage of the mold 54 and at each opening of the branched cooling water passage not shown. . The temperature of the cooling water passing through each opening is measured by these temperature sensors, and the measurement output signal is input to a control unit (not shown). This control unit is a central processing unit (CP
U), a RAM, and a ROM, which is a computer system mainly configured to control the operation of the mold cooling device 52. The opening degree of each flow rate adjusting valve is adjusted by a control signal from this control unit. The switching of the electromagnetic directional valves 70A, 70B, 70C is also performed by sending a control signal from this control unit to the electromagnetic solenoids of the respective electromagnetic directional valves.

Now, the mold cooling device 5 having such a structure
In 2, the cooling water passage 56A and the cooling water passage branched from the cooling water passage 56A cool the area of the part 54A of the mold 54. Further, a range of a part 54B of the mold 54 is formed by the cooling water passage 56B and a cooling water passage branched therefrom, and a range of a part 54C of the mold 54 is formed by the cooling water passage 56C and a cooling water passage branched therefrom. Each is cooled. The cooling control of each range 54A, 54B, 54C is performed in the same manner as in the first embodiment. That is, first, the molten metal is injected in a state where a small amount of cooling water is flown from the flow rate adjusting valves 62A, 62B, 62C side, and the cooling water temperature at each opening is measured. Then, the temperature difference between the supply port and each discharge port is calculated, and if all the temperature differences are within the predetermined range, cooling is continued, and if there is a temperature difference that is not within the predetermined range, The opening degree of each flow rate adjusting valve is adjusted. When the supply flow rate reaches a predetermined maximum value, the electromagnetic directional valve 70A, 70B or 70C is switched, and the cooling water supply of the corresponding cooling water supply mechanism is reversed. These controls are performed independently for each of the three systems of cooling water supply mechanism. Thereby, uniform and appropriate cooling can be performed over the entire mold 54. In particular, the advantage that uniform cooling can be achieved even when the mold 54 is large is obtained.

In this embodiment, the case where three cooling water supply mechanisms are provided has been described. However, two cooling water supply mechanisms or four or more cooling water supply mechanisms may be provided depending on the size of the mold. . Further, in each of the above-described embodiments, the case where the cooling water is used as the cooling medium of the mold is described, but the same action and effect can be obtained by using other cooling medium such as cooling oil and cooling air. be able to. Further, in each of the above-described embodiments, the cooling holes formed in the die are used as the cooling medium passages, but other types of cooling medium passages such as cooling pipes provided in close contact with the die are used. You can also The shape and structure of the cooling medium passage and the contents of the other steps of the cooling method for the mold are not limited to those in the above-described embodiments.

[0031]

In the invention according to the first and second aspects, it is possible to finely adjust the cooling in each part of the mold and to cool the mold uniformly. Further, in the inventions according to claims 3 and 4, the mold can be surely cooled to a uniform and optimum degree.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an overall configuration of a mold cooling device in a first embodiment of a mold cooling method according to the present invention.

FIG. 2 is a flowchart showing a procedure for cooling a mold in Example 1 of the method for cooling a mold.

FIG. 3 is a schematic diagram showing an overall configuration of a mold cooling device in a second embodiment of the mold cooling method according to the present invention.

[Explanation of Codes] 4 Mold 6,6A, ..., 6E, 8A, ..., 8E Cooling medium passage 10 One cooling medium supply port 10A, ..., 10F Two or more cooling medium discharge ports 12,12A ,. , 12F flow control valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Norihiko Tomioka 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Mitsuru Inui 1-9-6 Rokujo Minami Gifu City, Gifu Prefecture Gifu Seiki Industrial Co., Ltd. Company 1st Business Department (72) Inventor Kento Nimura 1-9-6 Rokujo Minami Gifu City, Gifu Prefecture Gifu Seiki Kogyo Co., Ltd. 1st Business Department (72) Inventor Akira Saito 1-9 Rokujo Minami Gifu City, Gifu Prefecture 6 Gifu Seiki Industry Co., Ltd. 1st Division

Claims (4)

[Claims] 1. A cooling medium passage of a mold is provided with two or more cooling medium discharge ports for one cooling medium supply port,
A flow rate adjusting valve is provided at each of the supply port and the two or more discharge ports, and the temperature of the cooling medium at the two or more discharge ports is measured so that variations in the measured two or more temperatures are reduced. A method of cooling a mold, characterized in that the opening of each of the flow rate adjusting valves is adjusted. 2. The mold cooling method according to claim 1, wherein the two or more temperature variations have a predetermined magnitude even when the supply amount of the cooling medium is a predetermined maximum amount. If not less than, supply the cooling medium from the discharge port farthest from the supply port of the two or more discharge ports,
A method of cooling a mold, characterized in that a supply direction of the cooling medium is changed so as to discharge the cooling medium from another discharge port and the supply port. 3. In the cooling medium passage of the mold, two or more cooling medium discharge ports are provided for one cooling medium supply port,
A flow rate adjusting valve is provided at each of the supply port and the two or more discharge ports, and the temperature difference between the temperature of the cooling medium at the supply port and the temperature of the cooling medium at the two or more discharge ports is measured. A method for cooling a mold, wherein the opening degree of each of the flow rate adjusting valves is adjusted so that all of the measured values of two or more temperature differences fall within a predetermined range. 4. The mold cooling method according to claim 3, wherein all of the two or more temperature difference values are within the predetermined range even when the supply amount of the cooling medium is set to a predetermined maximum amount. If it does not enter the inside, the cooling medium is supplied from the discharge port farthest from the supply port among the two or more discharge ports, and the cooling medium is discharged from the other discharge port and the supply port. A method for cooling a mold, which comprises changing the supply direction of the cooling medium.