Casting equipment and method for cooling casting molds

Abstract

To more effectively cool a casting for casting. [Solution] The casting mold device 20 comprises a first mold 40 including a first mold surface 42 and liquid passages 43, 44 through which a cooling liquid flows, a second mold surface 52, a plurality of inserts 58 that form recesses in the casting, three or more sprues 59 for pouring molten metal into the mold space, and a gas passage 53 through which a cooling gas flows, and the plurality of inserts 58 are arranged in a straight line, and the three or more sprues 59 are arranged in a staggered pattern with inserts 58 arranged between them.

Description

[Technical Field]

[0001] This disclosure relates to a casting apparatus and a method for cooling a casting mold. [Background technology]

[0002] Patent Document 1 discloses a casting mold in which cooling water is supplied to passages set inside the casting mold to cool the mold. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-85420 Summary of the Invention [Problem to be solved by the invention]

[0004] To further improve casting productivity, it is desirable to cool castings more effectively.

[0005] Therefore, an object of the present disclosure is to enable castings to be cooled more effectively. [Means for solving the problem]

[0006] In order to solve the above problem, a casting apparatus includes a cooling liquid supply source that supplies cooling liquid to an inlet supply passage connected to the inlet of a liquid passage used to cool a casting mold; a valve interposed between the cooling liquid supply source and the outlet of the inlet supply passage; a vacuum device connected to an outlet main fluid passage connected to the outlet of the liquid passage, and which, when the valve is closed, sucks out gas from the liquid passage to create a vacuum inside the liquid passage; and a controller that controls the opening and closing of the valve, wherein, when the valve is closed, the controller uses the vacuum device to suck out gas from the liquid passage, and after creating a vacuum inside the liquid passage, opens the valve and introduces the cooling liquid into the liquid passage.

[0007] In addition, to solve the above problem, a method of cooling a casting mold involves using a vacuum device to suck out gas from within the liquid passage used to cool the casting mold while closing a valve located between a cooling liquid supply source and the outlet of an inlet-side supply passage connected to the inlet of the liquid passage, and after creating a vacuum within the liquid passage through suction by the vacuum device, opening the valve to introduce cooling liquid into the liquid passage, and continuing to supply the cooling liquid to the liquid passage until mold molding is completed. [Effects of the Invention]

[0008] The present disclosure allows for more effective cooling of foundry castings. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the overall configuration of a casting mold device. [Figure 2] FIG. 2 is a schematic bottom view showing the upper body of the second mold. [Figure 3] FIG. 3 is a schematic plan view showing the first type. [Figure 4] FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a block diagram showing an example of a configuration in which the first coolant supply device supplies coolant to a plurality of pin fluid passages in the casting mold. [Figure 6] FIG. 6 is a flowchart showing the flow of the mold controller controlling the supply of coolant to the pin liquid passage. DETAILED DESCRIPTION OF THE INVENTION

[0010] {Embodiment} <Overall structure> 1 is a diagram showing the overall configuration of a casting mold apparatus 20, a casting apparatus, and a method for manufacturing a casting according to an embodiment of the present invention.

[0011] Casting mold apparatus 20 is an apparatus for producing casting 10 by casting. Casting is a processing method in which a metal such as an aluminum alloy is melted to form a molten metal, which is poured into a casting mold 30 and solidified into a predetermined shape within casting mold 30. Casting 10 is produced, for example, by low-pressure casting or gravity casting.

[0012] In this embodiment, the casting 10 is a cylinder head 10 for an internal combustion engine. The cylinder head 10 has a ceiling portion 12 that closes one end of a combustion chamber in the internal combustion engine. A spark plug mounting hole 12h for inserting an ignition plug is formed in the ceiling portion 12. In the following description, on the assumption that the combustion chamber and the spark plug mounting hole 12h of the cylinder head 10 are arranged along the direction of gravity and that the combustion chamber is arranged below the ceiling portion 12, reference may be made to up or down with respect to the direction of gravity.

[0013] A space for forming a water jacket and a space for forming a cam chamber are formed above the ceiling portion 12 of the cylinder head 10. These spaces may be formed by a sand core or by the mold surface of the casting mold 30.

[0014] In this embodiment, the cylinder head 10 is assumed to be a cylinder head for an in-line internal combustion engine in which multiple combustion chambers are arranged in series. Therefore, the cylinder head 10 is formed in a rectangular parallelepiped shape that is long in one direction, and multiple ceiling sections 12 are linearly arranged at intervals along the longitudinal direction. The number of combustion chambers, i.e., the number of ceiling sections 12, is any number equal to or greater than two. In this embodiment, an example in which four ceiling sections 12 are linearly arranged, i.e., a cylinder head 10 for a four-cylinder in-line internal combustion engine, will be described. The cylinder head 10 may also be a cylinder head for a V-type internal combustion engine or a horizontally opposed internal combustion engine. The cylinder head 10 has recessed upper combustion chambers, intake ports, and exhaust ports. Injector mounting holes may also be formed in the cylinder head 10.

[0015] The casting mold apparatus 20 includes a casting mold 30 and a casting device 70. The casting mold 30 is a portion including a mold surface for molding the cylinder head 10. The casting mold 30 is set in the casting device 70. The casting device 70 is an apparatus for casting the cylinder head 10 using the set casting mold 30. For example, the casting device 70 may control the timing of cooling the casting mold 30. The casting device 70 may further control the timing of opening and closing the mold, the timing of supplying molten metal to the casting mold 30, etc.

[0016] All or part of the casting mold 30 set in the casting device 70 may be replaceable. This allows the casting mold device 20 to use the mold surface of the replaced casting mold 30 to cast cylinder heads 10 with different shapes.

[0017] The casting mold 30 includes a first mold 40 and a second mold 50. The first mold 40, the second mold 50, and an intermediate mold 32 described below are made of a material that can withstand the temperature of the molten metal, such as metal.

[0018] The first die 40 has a first die surface 42. The first die surface 42 forms the surface of the outward surface of the cylinder head 10 that is observed from one side. In this embodiment, the first die surface 42 forms the outward surface of the cylinder head 10 that faces upward. The first die surface 42 forms, for example, the upper edge of the cylinder head 10, the spark plug mounting hole 12h, part of the cam chamber, etc. The first die 40 is located above the second die 50. The first die 40 may also be referred to as an upper die. The first die 40 may be formed by combining multiple parts.

[0019] The second die 50 has a second die surface 52. The second die surface 52 forms the outward surface of the cylinder head 10 that is observed from the other side opposite the first die 40. In this embodiment, the first die surface 42 forms the outward surface of the cylinder head 10 that faces downward. The second die surface 52 forms, for example, the lower edge of the cylinder head 10 and the upper recessed portion of the combustion chamber. The lower edge of the cylinder head 10 is the portion that abuts against the upper edge of the cylinder block via a gasket or the like. The second die 50 is located below the first die 40. The second die 50 may also be referred to as a lower die. The second die 50 may be formed by combining multiple parts.

[0020] In this embodiment, the casting mold 30 further includes an intermediate mold 32 located between the first mold 40 and the second mold 50. The intermediate mold 32 is disposed between the first mold 40 and the second mold 50. The intermediate mold 32 is assumed to have a mold surface 33 that forms the lateral outward surface of the cylinder head 10. The intermediate mold 32 may be divided into multiple parts around the cylinder head 10, and each of the divided intermediate molds 32 may be able to move toward and away from the cylinder head 10 in the horizontal direction. This facilitates casting even if the lateral outward surface of the cylinder head 10 has a complex shape. The presence of the intermediate mold 32 is not essential, and a portion corresponding to the intermediate mold 32 may be integrated into the first mold 40 or the second mold 50.

[0021] It should be noted that at least one of the first die surface 42, the second die surface 52 and the intermediate die 32 may form the outward surface of the cylinder head 10 together with the sand core.

[0022] Three or more gates 59 are formed in the second mold 50. An intermediate stalk 60 is disposed below the second mold. The intermediate stalk 60 has a pouring pool space 61 that gradually becomes larger as it goes upward. The lower openings of the multiple gates 59 face the upper opening of the intermediate stalk 60. Molten metal is supplied into the pouring pool space 61 from the bottom side thereof, and is supplied from the pouring pool space 61 through the multiple gates 59 into the mold space formed by the first mold surface 42, the second mold surface 52, and the mold surface 33.

[0023] The first die 40 is formed with liquid passages 43 and 44 through which a cooling liquid flows. After the molten metal flows into the die space, the first die 40 is cooled by the cooling liquid flowing in the liquid passages 43 and 44. The second die 50 is formed with gas passages 53 and 54 through which a cooling gas flows. After the molten metal flows into the die space, the second die 50 is cooled by the cooling gas flowing in 53 and 54.

[0024] The casting device 70 includes a mold controller 72 and a first coolant supply device 80. The first coolant supply device 80 supplies coolant to the liquid passage 44 and causes the coolant to flow through the liquid passage 44. The mold controller 72 controls the first coolant supply device 80, thereby controlling the timing of cooling of the first mold 40 by the coolant flowing through the liquid passage 44.

[0025] The casting device 70 further includes a second coolant supply device 78 and a cooling gas supply device 79. The second coolant supply device 78 supplies coolant to the liquid passage 44. The cooling gas supply device 79 supplies cooling gas to the gas passages 53 and 54. The mold controller 72 controls the timing of cooling the first mold 40 by the coolant flowing through the liquid passages 43 and 44 and the timing of cooling the second mold 50 by the gas flowing through the gas passages 53 and 54 by controlling the first coolant supply device 80, the second coolant supply device 78, and the cooling gas supply device 79.

[0026] The mold controller 72 may control the timing of opening and closing the mold, the timing of supplying molten metal to the casting mold 30, and the like.

[0027] The mold controller 72 may be connected to a switch 71. The switch 71 is, for example, a switch that receives a command to start casting from the casting mold device 20. In response to the start command to the switch 71, the mold controller 72 may control each part of the casting mold device 20. For example, it is assumed that the mold controller 72 has a built-in timer 72t, the timer 72t starts measuring time in response to the start command to the switch 71, and when the time measured by the timer 72t reaches a predetermined time, each part of the casting mold device 20 is controlled.

[0028] The timekeeping function of the timer 72t may be realized by any configuration that outputs an ON signal after a preset time has elapsed in response to some input. For example, the timer 72t may be realized by a processor 72P, which is an electric circuit, executing a program stored in a storage unit, or may be realized by a delay circuit that outputs a delay signal after a preset time has elapsed after a start command is input to the switch 71.

[0029] <About Type 2> The second mold 50 will now be described in more detail. Figure 2 is a schematic bottom view showing the upper body 50U of the second mold 50. In Figure 2, the outer periphery of the cylinder head 10 is indicated by a two-dot chain line. It is assumed that the outer periphery of the cylinder head 10 is determined by the mold surface 33 of the intermediate mold 32.

[0030] As shown in FIGS. 1 and 2, the second die 50 includes a second die body 51 and a plurality of inserts 58.

[0031] The second mold body 51 is formed in a rectangular plate shape. In this embodiment, the second mold body 51 is configured by laminating an upper body 50U and a lower body 50L.

[0032] A plurality of insert setting recesses 50Uh are formed in the upper body 50U. In this embodiment, four insert setting recesses 50Uh are formed so as to be aligned in a straight line at intervals. Each insert setting recess 50Uh is formed at a position corresponding to each combustion chamber in the cylinder head 10. The shape of the insert setting recess 50Uh is formed to correspond to the shape of the combustion chamber.

[0033] The insert 58 protrudes from the upper surface of the upper body 50U and forms a recess in the cylinder head 10. In other words, the upper space of the combustion chamber extends below the ceiling portion 12 of the cylinder head 10, and the insert 58 forms the recess that forms the upper space of the combustion chamber. The inner surface of the recess is the upper wall that separates the upper space of the combustion chamber. The upper part of the insert 58 may be formed with partial protrusions to form intake ports, exhaust ports, etc.

[0034] The lower portions of the plurality of (four in this embodiment) nesting elements 58 are housed in the nesting element setting recess 50Uh, so that the plurality of nesting elements 58 are held in a state of being aligned in a straight line with intervals therebetween.

[0035] The core 58 is formed in a columnar shape corresponding to the shape of the combustion chamber. In this embodiment, the core 58 is formed in a shape like a cylinder with both side portions thereof cut out in a plane perpendicular to the direction in which the cores 58 are linearly arranged. The core 58 may be formed in another shape, for example, a columnar shape. The core 58 may be a part that is integrally molded from the same material as the other parts of the second die 50.

[0036] The second mold body 51 is formed with three or more gates 59 for pouring molten metal into the mold space. The three or more gates 59 are arranged in a staggered pattern with a nest 58 placed between them. A staggered arrangement means that the gates are arranged alternately left and right in a certain direction. The nest 58 is arranged between the gates 59 means that, in a plan view seen along the direction of gravity, any part of the nest 58 is arranged on a line connecting the centers of the two gates 59. The center of the gate 59 is, for example, the geometric center of the shape of the upper opening of the gate 59 when viewed in a plan view.

[0037] In this embodiment, the second die 50 includes four nesting dies 58. The second die body 51 includes four gates 59. A line on which the centers of the four nesting dies 58 (for example, the geometric centers of the nesting dies 58 in a plan view) are aligned is defined as the nesting arrangement line L. In the direction along the nesting arrangement line L, three of the four gates 59 are located between the four nesting dies 58, and the remaining gate is located on one side of two of the nesting dies 58. More specifically, the centers of three of the four gates 59 are positioned away from the spaces between the four nesting dies 58 in a direction perpendicular to the nesting arrangement line L. The remaining gate 59 is positioned away from the four nesting dies 58 in the direction along the nesting arrangement line L, and is positioned away from the four nesting dies 58 in a direction perpendicular to the nesting arrangement line L.

[0038] When viewed along the nesting arrangement straight line L, the gate 59 at the extreme end of the four gates 59 and the gate 59 immediately next thereto are located apart on one side perpendicular to the nesting arrangement straight line L. When viewed along the nesting arrangement straight line L, the gate 59 located next to the gate 59 at the extreme end of the four gates 59 and the gate 59 immediately next thereto are located apart on the other side perpendicular to the nesting arrangement straight line L.

[0039] In other words, the multiple gates 59 are alternately positioned on one side and the other side perpendicular to the insert placement straight line L. Therefore, any one insert 58 is positioned between two adjacent gates 59 when viewed along the insert placement straight line L. For this reason, the distance between the gates 59 can be made larger compared to when two gates are positioned between two inserts 58 adjacent in the direction along the insert placement straight line L. By making the distance between the gates 59 larger, it becomes easier to smoothly supply molten metal to dispersed positions in the mold space.

[0040] The second die 50 has a gas passage 53. The gas passage 53 has a cooling gas outlet 53a for blowing cooling gas.

[0041] In this embodiment, Y-shaped grooves 50Ug are formed on the lower surface of the upper body 50U. Here, one Y-shaped groove 50Ug is formed corresponding to two inserts 58 near one end in the direction along the insert placement straight line L, and another Y-shaped groove 50Ug is formed corresponding to two inserts 58 near the other end in the direction along the insert placement straight line L.

[0042] The Y-shaped groove 50Ug is a groove that opens to the lower surface of the upper body 50U. One end of the Y-shaped groove 50Ug opens to one side edge of the upper body 50U. The other two ends of the Y-shaped groove 50Ug extend toward the center (e.g., the geometric center in a plan view) of two adjacent cores 58. A through-hole 50Ua that penetrates vertically is formed in the bottom of the core setting recess 50Uh of the upper body 50U. A hole that is continuous with the through-hole 50Ua may also be formed in the bottom of the core 58.

[0043] Two cooling gas pipes 55 are arranged in the Y-shaped groove 50Ug. The middle portions of the cooling gas pipes 55 are arranged in the Y-shaped groove 50Ug. The base ends of the cooling gas pipes 55 are located on the opening side of one side edge of the upper body 50U. Cooling gas is supplied into the cooling gas pipes 55 from the outside through the opening on the base end side. The tip ends of the cooling gas pipes 55 face the center of the core 58 and pass through the through hole 50Ua to face the bottom of the core 58. The internal space of the cooling gas pipe 55 is the gas passage 53, and the tip end opening is the cooling gas outlet 53a.

[0044] Some of the cooling gas outlets 53a are located in an area surrounded by multiple gates 59. In this embodiment, the first three cooling gas outlets 53a from one end along the nesting arrangement straight line L are cooling gas outlets 53a (hereinafter sometimes distinguished from cooling gas outlets 53as) that blow cooling gas onto the second mold 50 in an area surrounded by multiple gates 59 (in this embodiment, a quadrangular area surrounded by four gates 49). These cooling gas outlets 53a are also outlets located between two of the multiple gates 59.

[0045] The sprayed cooling gas can flow out through the gap between the Y-shaped groove 50Ug and the cooling gas pipe 55. The configuration of the cooling gas pipe 55 is not limited to the above example. A single Y-shaped pipe may be disposed within the Y-shaped groove 50Ug. Alternatively, multiple pipes may branch out from a single pipe and flow toward each of the spray target locations.

[0046] In this embodiment, a hole 50Ub is formed from the outer peripheral surface of the upper body 50U toward the center of the upper body 50U. The tip of the hole 50Ub is located between the inserts 58 closer to the center. A cooling gas pipe 56 is disposed within the hole 50Ub. The base end of the cooling gas pipe 56 is exposed from the upper body 50U, and the tip of the cooling gas pipe 56 faces the tip of the hole 50Ub. The internal space of the cooling gas pipe 56 is the gas passage 54, and the opening at the tip side is the cooling gas outlet 54a. The cooling gas outlet 54a is an area surrounded by multiple gates 59 and sprays cooling gas onto the second mold 50.

[0047] That is, cooling gas is supplied into the cooling gas pipe 56 from the outside through the opening on the base end side of the cooling gas pipe 56. The cooling gas supplied into the cooling gas pipe 56 is blown onto the tip of the hole 50Ub. This effectively cools the middle portion of the upper body 50U of the second mold 50 from the inside. The cooling gas coming out of the cooling gas pipe 56 can flow out through the gap between the hole 50Ub and the cooling gas pipe 56.

[0048] Because molten metal is supplied to the gates 59, the temperature of the cylinder head 10 in the mold space around the gates 59 may become high. As a result, the temperature of the portion of the cylinder head 10 surrounded by the gates 59 may also be high. The portion surrounded by the gates 59 is a polygonal area that can encompass the gates 59. By spraying gas from the cooling gas outlets 53as and 54a onto the portion surrounded by the gates 59, it is possible to effectively cool the portion of the cylinder head 10 that is likely to become hot, which may contribute to achieving directional solidification. It is not necessary to have all of the cooling gas outlets 53as and 54a; for example, only the cooling gas outlet 53as or only the cooling gas outlet 54a may be provided.

[0049] <About Type 1> The first die 40 will be described in more detail. Fig. 3 is a schematic plan view showing the first die 40. In Fig. 3, the outer peripheral edge of the cylinder head 10 is indicated by a two-dot chain line. Fig. 4 is a schematic cross-sectional view taken along line IV-IV in Fig. 3. Fig. 4 shows the intermediate die 32 and a part of the second die 50.

[0050] As described above, the first mold 40 has liquid passages 43, 44 through which the coolant flows.

[0051] The liquid passage 43 is an example of a through liquid passage 43 that penetrates the first mold 40 in a direction intersecting the direction of gravity. In this embodiment, the through liquid passage 43 penetrates the first mold 40 in a direction perpendicular to the direction of gravity. More specifically, the first mold 40 has a plurality of (two in this embodiment) through liquid passages 43.

[0052] The through liquid passage 43 extends linearly along the nesting arrangement straight line L. Both ends of the through liquid passage 43 are connected to fittings that protrude outward from the first die 40. The cooling liquid is supplied into the through liquid passage 43 through an opening on one side of the through liquid passage 43. The cooling liquid that flows inside the through liquid passage 43 flows out through an opening on the other end side of the through liquid passage 43.

[0053] In plan view, the liquid through passages 43 are positioned away from each other in a direction perpendicular to the insert arrangement line L. In plan view, the liquid through passages 43 are positioned outward and away from the cylinder head 10.

[0054] The number of liquid through-passages 43 is not limited to the above example, and may be one, or three or more. The extending direction of the liquid through-passages 43 is not limited to the above example, and may extend in a direction diagonal or perpendicular to the nesting arrangement line L. The liquid through-passages 43 may extend in a direction diagonal to the direction of gravity.

[0055] In this embodiment, the first die 40 has a core pin 41. The core pin 41 is a pin-shaped portion that protrudes from the first die 40 toward the second die 50 and forms a blind hole or a through hole in the cylinder head 10. In this embodiment, the first die 40 has a plurality of core pins 41 corresponding to each insert 58. The core pins 41 are formed at the center of the insert 58 and form the respective spark plug mounting holes 12h. The core pin 41 is an elongated portion formed separately from the other portions of the first die 40 and may be a portion attached to the other portions of the first die 40. The core pin 41 may also be a portion that is integrally molded from the same material as the other portions of the first die 40.

[0056] The liquid passage 44 is an example of a pin liquid passage 44 that allows a coolant to flow inside the core pin 41.

[0057] That is, a bottomed hole 41h is formed from the top surface of the first die 40 toward the inside of the core pin 41. The bottom of the bottomed hole 41h only needs to reach the core pin 41, and it does not matter whether it reaches the tip of the core pin 41.

[0058] A cooling pipe 45 is inserted into the bottomed hole 41h. The cooling pipe 45 is a pipe that supplies and recovers cooling liquid into the bottomed hole 41h. The cooling pipe 45 has an inner pipe 45a, an outer pipe 45b, and a base end 45c. The base end 45c has two joints. The inner pipe 45a and the outer pipe 45b extend in the same direction from the base end 45c. The outer diameter of the inner pipe 45a is smaller than the inner diameter of the outer pipe 45b. The inner pipe 45a is disposed inside the outer pipe 45b, and a space through which the cooling liquid can pass is formed between the inner pipe 45a and the outer pipe 45b.

[0059] The tip of the inner tube 45a protrudes beyond the tip of the outer tube 45b. The tip of the inner tube 45a is positioned opposite the bottom of the bottomed hole 41h, and the cooling liquid ejected from the tip of the inner tube 45a flows into the bottom of the bottomed hole 41h. The tip of the outer tube 45b is positioned above and spaced apart from the bottom of the bottomed hole 41h. The cooling liquid that flows into the bottom of the bottomed hole 41h passes between the inner tube 45a and the bottomed hole 41h, flows into the tip-side opening of the outer tube 45b, and further passes between the inner tube 45a and the outer tube 45b and flows into the base end 45c. The passage within the inner tube 45a is the pin liquid passage 44.

[0060] A cooling pipe 45 is inserted corresponding to each of the plurality of core pins 41. The pin liquid passages 44 of the plurality of cooling pipes 45 do not communicate with each other. Therefore, the plurality of pin liquid passages 44 are also an example of a plurality of independent liquid passages through which the coolant flows independently of each other.

[0061] <Configuration for supplying coolant> An example of a configuration for supplying coolant to the liquid passages 43, 44 will now be described. Figure 5 is a block diagram showing an example of a configuration in which a first coolant supply device 80 supplies coolant to a plurality of pin liquid passages 44 of the casting mold 30.

[0062] The first coolant supply device 80 includes a coolant tank 81 , a valve 82 , and a vacuum device 83 .

[0063] The cooling water tank 81 is a tank that stores cooling water as a cooling liquid, and is an example of a cooling liquid supply source that supplies cooling liquid to the pin liquid passage 44. The cooling liquid may be cooling water or another liquid.

[0064] Valve 82 is interposed between cooling water tank 81 and pin liquid passage 44, and switches between a state in which cooling water tank 81 can supply cooling water to pin liquid passage 44 and a state in which the supply is cut off. Valve 82 is, for example, an electromagnetic valve that can be controlled to open and close by an on / off electrical signal.

[0065] In this embodiment, a valve 82 is provided corresponding to each of the pin liquid passages 44, which are multiple independent liquid passages. In this embodiment, four valves 82 are provided corresponding to the four pin liquid passages 44.

[0066] The cooling water tank 81 and the multiple valves 82 are connected by separate pipes 89a, and the multiple valves 82 are connected by separate pipes 89b to the inlet-side joints of the multiple pin liquid passages 44. Therefore, the cooling liquid is supplied from the cooling water tank 81 to the multiple pin liquid passages 44 via separate routes, and the supply state is switched by the separate valves 82. Note that pipes 89b are an example of inlet-side supply paths connected to the inlets of the pin liquid passages 44 for cooling of the casting mold 30, which is a casting mold.

[0067] The vacuum device 83 is a vacuum pump that sucks liquid. The outlet-side joints of the multiple pin liquid passages 44 are connected to separate pipes 89c, and the separate pipes 89c are combined into a single collecting pipe 89d and connected to a suction-side connection port of the vacuum device 83. The outlet of the vacuum device 83 is connected to the cooling water tank 81 via a return pipe 89e. The pipe 89c is an example of an outlet-side main fluid passage connected to the outlet of the pin liquid passage 44.

[0068] When the vacuum device 83 performs a suction operation, the space inside the tubes 89c and 89d is suctioned, and the space inside the multiple pin liquid passages 44 connected to the tube 89c is also suctioned. When the air inside the tubes 89c and 89d and the multiple pin liquid passages 44 is suctioned with each valve 82 closed, a vacuum state is created in the spaces inside the tubes 89c and 89d and each pin liquid passage 44. Note that the vacuum state here refers to a state that is close to a vacuum compared to atmospheric pressure.

[0069] After each pin liquid passage 44 is evacuated, when each valve 82 is opened, the cooling liquid in the cooling water tank 81 flows into each pin liquid passage 44 all at once. This allows for rapid cooling at the timing when cooling is about to begin. When the suction operation of the vacuum device 83 continues, the cooling liquid in each pin liquid passage 44 is returned to the cooling water tank 81 via pipes 89c and 89d and return pipe 89e.

[0070] The timing for opening and closing the plurality of valves 82 can be set arbitrarily by individually controlling the timer 72t. For example, suppose that the elapsed time from the input timing of the casting start command is set in advance for each valve 82. The timer 72t starts counting from the input timing of the casting start command, and when the timer reaches the respective preset elapsed time, the mold controller 72 can issue an open command to each valve 82.

[0071] With the above configuration, each valve 82 can be opened while the suction operation by the vacuum device 83 continues, regardless of the temperature of the casting mold 30. Furthermore, by individually controlling the opening and closing of the multiple valves 82, it is possible to individually control the cooling timing of each part, for example by individually shifting the cooling timing of each core pin 41.

[0072] The second coolant supply device 78 that supplies coolant to the liquid passage 43 may also have a configuration similar to that of the first coolant supply device 80. The first coolant supply device 80 and the second coolant supply device 78 may be the same device, and the coolant may be supplied to the liquid passages 43 and 44 from the same single coolant supply device.

[0073] The cooling gas supply device 79 that supplies the cooling gas to the gas passage may be any of various blower devices capable of blowing gas, such as a blower fan.

[0074] The collecting pipe 89d may be provided with a pressure gauge 84 that detects the pressure inside the collecting pipe 89d. If there is no gas leak between the valve 82 and the vacuum device 83, the pressure detected by the pressure gauge 84 decreases as the vacuum device 83 performs its suction operation. If there is a gas leak between the valve 82 and the vacuum device 83, air will flow from the outside into the space connecting the collecting pipe 89d and the like, and it is expected that the pressure detected by the pressure gauge 84 will not decrease as much as expected. For this reason, by monitoring the pressure detected by the pressure gauge 84, the presence or absence of a leak between the valve 82 and the vacuum device 83 can be detected. This effectively prevents the cooling liquid from leaking.

[0075] <Coolant supply timing> 6 is a flowchart showing the flow of the mold controller 72 controlling the supply of coolant to the pin liquid passage 44. This flowchart may be considered as an algorithm executed by the processor 72P when the function of the timer 72t is implemented in a computer including the processor 72P. Note that in the initial state, the valve 82 is closed. Also, it is assumed that the vacuum device 83 continues to perform a suction operation.

[0076] In step S1, it is determined whether or not a command to start casting has been issued. For example, if it is determined that a command to start casting has been issued by turning on switch 71, the process proceeds to step S2.

[0077] In step S2, processing for casting is performed, such as a process for closing the first die 40, the second die 50, and the intermediate die 32, and a process for pouring molten metal into the die space after the die closing.

[0078] In the next step S3, it is determined whether a predetermined water flow time has elapsed. Whether the water flow time has elapsed can be determined, for example, by comparing the time elapsed from an initial time associated with the time when the molten metal is poured into the mold space with a predetermined suction start time. The initial time may be any time associated with the time when the molten metal is poured into the mold space. For example, the initial time may be the time when the molten metal is poured into the mold space. If the molten metal is poured after a certain period of time has elapsed after the switch 71 is turned on and a predetermined process is performed, the initial time may be the time when the switch 71 is turned on. The processing of step S3 is repeated until it is determined that the time elapsed from the initial time has elapsed. If it is determined that the water flow start time has elapsed, the processing proceeds to the next step S4.

[0079] In step S4, a command to open the valves 82 is given to each valve 82. Because each pin liquid passage 44 is in a vacuum state, the cooling liquid in the cooling water tank 81 flows into each pin liquid passage 44 via pipe 89a, valve 82, and pipe 89b. As the suction operation of the vacuum device 83 continues, the cooling liquid in each pin liquid passage 44 is returned to the cooling water tank 81 from pipes 89c and 89d through the return pipe 89e. Therefore, the cooling liquid in the cooling water tank 81 is continuously supplied into each pin liquid passage 44. As a result, the molten metal poured into the mold space is cooled mainly at the portion that comes into contact with the core pin 41.

[0080] The valves 82 may be set to start passing water at different times, and each valve 82 may be opened at different times. This allows the core pins 41 to start cooling at different times.

[0081] The molten metal injected into the mold space is also cooled by the cooling liquid flowing through the through liquid passage 43 and the cooling gas sprayed from the cooling gas outlet 53a. These cooling liquid and cooling gas are preferably supplied after a time has elapsed that is considered to have been spent on injecting the molten metal into the mold space. The timing at which the supply of cooling liquid to the through liquid passage 43 is started, the timing at which the supply of cooling liquid to the pin liquid passage 44 is started, and the timing at which the supply of cooling gas to the gas passage 53 is started may be the same or different.

[0082] In the next step S5, it is determined whether or not the casting has been completed. The determination of whether or not the casting has been completed may be based on, for example, whether or not a predetermined time has elapsed since a predetermined reference time other than the initial time. Alternatively, the determination of whether or not the casting has been completed may be based on, for example, whether or not the time elapsed since the initial time has elapsed a predetermined time required for the molten metal in the mold space to solidify. When it is determined that the casting has been completed, a cooling completion process, such as a process of closing each valve 82, is executed as shown in step S6. This completes the cooling process.

[0083] <Effects of the embodiment> According to the casting mold apparatus 20 configured as described above, the first die 40 has liquid passages 43 and 44 formed therein, and the second die 50 has a gas passage formed therein. This allows the molten metal in the mold space to be cooled quickly. By quickly cooling the molten metal in the mold space, the casting 10 can be produced quickly while reducing defects in the casting 10.

[0084] Furthermore, because the specific heat of a liquid is greater than that of a gas, cooling can be achieved more quickly with a cooling liquid than with a cooling gas. If the first mold 40 can be cooled faster than the second mold 50, directional solidification can be achieved, starting from the first mold 40 farthest from the gate 59 and ending with the second mold 50 closest to the gate 59. This allows sink marks due to cooling to be concentrated near the gate 59, thereby reducing defects in the casting 10 caused by sink marks.

[0085] Furthermore, because three or more gates 59 are arranged in a staggered pattern with the inserts 58 disposed between them, the gates 59 in the second mold 50 are spaced apart by the space between the inserts 58. This disperses the gates 59, which tend to become hot, compared to when the inserts are arranged continuously on one side along a straight line. This disperses heat among the second mold 50 and the areas close to the second mold 50, allowing for rapid cooling of the molten metal in the mold space. This also allows the casting 10 to be produced quickly while suppressing defects in the casting 10.

[0086] Furthermore, since three or more gates 59 are arranged in a staggered manner for the plurality of inserts 58 arranged in a straight line, the plurality of inserts 58 and the three or more gates 59 can be arranged at intervals.

[0087] Furthermore, the gas passage 53 has cooling gas outlets 53as and 54a that blow cooling gas into the area surrounded by the gates 59, so that the area of ​​the second mold 50 surrounded by the gates 59 can be quickly cooled, and directional solidification can be achieved so that the cooling of the gates 59 is relatively slow. This allows sink marks to be concentrated near the gates 59, and defects in the casting 10 caused by sink marks can be suppressed.

[0088] Furthermore, since the liquid passages 43, 44 have the through liquid passage 43 that penetrates in a direction intersecting the direction of gravity, the first mold 40 can be effectively cooled by the cooling liquid that flows through the through liquid passage 43. This makes it possible to more effectively achieve the above-mentioned directional solidification.

[0089] Furthermore, the liquid passages 43, 44 include the pin liquid passage 44 for flowing cooling liquid inside the core pin 41, so that the molten metal in the mold space can be quickly cooled from the inside where the core pin 41 passes.

[0090] Furthermore, the liquid passages 43, 44 have a plurality of pin liquid passages 44 as independent liquid passages through which the coolant flows independently of one another, and a valve 82 is provided corresponding to each of the plurality of pin liquid passages 44. Therefore, by using each valve 82 to control the timing at which the coolant flows to each of the plurality of pin liquid passages 44, it is possible to achieve desirable directional solidification.

[0091] Furthermore, the casting mold device 20 or the casting device 70 is equipped with a valve 82 and a vacuum device 83, and with the pin liquid passage 44 in a vacuum state using the vacuum device 83, the valve 82 opens to allow the coolant in the cooling water tank 81 to flow through the pin liquid passage 44. This allows the coolant to flow into the pin liquid passage 44 all at once, enabling rapid cooling.

[0092] Furthermore, when the coolant is pumped, it is possible that the pressure will cause the coolant to leak. In this embodiment, the coolant in the cooling water tank 81 is guided into the passages in the casting mold 30 by suctioning the passages in the casting mold 30. This prevents the high pressure caused by the coolant from acting on the passages in the casting mold 30, making it less likely that the coolant will leak.

[0093] If there is a leak in a passage in the casting mold 30, the gas pressure detected during suction will be small, allowing the leak to be discovered in advance. Furthermore, even if cooling water is sucked into the passage in the casting mold 30, suction at the leaking location will continue, preventing leakage from the leaking location.

[0094] Furthermore, because the timing of opening and closing the valve 82 is controlled by the time measured by the timer 72t, stable casting is possible regardless of the thermophysical properties of the casting mold 30. For example, consider measuring the temperature at a location within the casting mold 30 and controlling the timing of opening and closing the valve 82 based on that temperature. Even in this case, since it is difficult to directly measure the heat of the molten metal, the temperature at a location within the casting mold 30 is measured. However, the temperature at a location within the casting mold 30 may not accurately reflect the temperature of the molten metal. For example, in a case where multiple castings 10 are continuously produced, the temperature of the casting mold 30 is low during the first production run, but the overall temperature of the casting mold 30 increases with each casting run. Therefore, as the number of production runs of the casting 10 increases, the detected temperature of the casting mold 30 is expected to be higher, and the timing of opening and closing the valve 82 is expected to gradually become misaligned.

[0095] In contrast, by controlling the valves 82 over time, stable casting becomes possible without being affected by the temperature of the casting mold 30. Furthermore, by individually controlling the multiple valves 82 over time, it becomes possible to achieve ideal cooling by quickly cooling areas that become relatively hot and preventing areas that become relatively cold from becoming too cold.

[0096] As described above, the casting apparatus 70 equipped with the valve 82 and the vacuum device 83 has a configuration in which the vacuum device 83 creates a vacuum in the pipe 89d and then opens the valve 82. This configuration is applicable to various casting molds having liquid passages. Therefore, the casting mold attached to the casting apparatus 70 does not have to be the casting mold 30 having the above-described insert 58 and gate 59. Of course, in this case, the casting mold does not have to be a mold for manufacturing the cylinder head 10.

[0097] Furthermore, according to the manufacturing method for the casting 10 of this embodiment, the molten metal in the mold space is cooled by the cooling liquid flowing through the liquid passages 43 and 44 to harden the molten metal, and the casting 10 formed by the hardening of the molten metal is removed from the casting mold device 20, so that the casting 10 can be cooled more effectively by the cooling liquid flowing through the liquid passages 43 and 44.

[0098] <Modification> The casting to be produced does not necessarily have to be a cylinder head 10. The casting may be another part of an internal combustion engine, such as a cylinder block. The casting may also be something other than a component of an internal combustion engine.

[0099] The positional relationship between the first mold 40 and the second mold 50 is not limited to the example in the above embodiment. For example, the first mold may be disposed below the second mold. Furthermore, the first mold and the second mold may be positioned so as to face each other horizontally or obliquely.

[0100] The number of nesting parts 58, the number of gates 59, and the positional relationship of the gates 59 to the multiple nesting parts 58 are not limited to the above example. For example, there may be two, three, or five or more nesting parts 58. There may be three or five or more gates 59. Two or more nesting parts may be present between adjacent gates in the direction along the nesting part arrangement straight line L. In other words, it is sufficient that the multiple gates located on both sides of the nesting part arrangement straight line, which is the direction in which the nesting parts are lined up, are arranged alternately and offset in the direction along the nesting part arrangement straight line.

[0101] The configurations described in the above embodiment and modifications can be combined as appropriate as long as they are not mutually contradictory.

[0102] <Additional Notes> The present disclosure discloses the following aspects.

[0103] The first aspect is a casting mold device comprising a first mold including a first mold surface and a liquid passage through which a cooling liquid flows, a second mold including a second mold surface, a plurality of inserts that form recesses in the casting, three or more gates for pouring molten metal into the mold space, and a gas passage through which a cooling gas flows, wherein the plurality of inserts are arranged in a linear line, and the three or more gates are arranged in a staggered pattern with the inserts positioned between them.

[0104] According to this casting mold device, a liquid passage is formed in the first mold, and a gas passage is formed in the second mold. Cooling can be performed more quickly using a cooling liquid than using a cooling gas. This allows for directional solidification in the order of the first mold to the second mold. Furthermore, the multiple gates in the second mold are spaced apart by the space required for the insert. This distributes the gates, which tend to become hot, and allows for rapid cooling. These features allow for more effective cooling of the casting while achieving directional solidification.

[0105] Furthermore, since the three or more gates are arranged in a staggered pattern with respect to the plurality of inserts arranged in a straight line, the plurality of inserts and the three or more gates can be arranged at intervals from one another.

[0106] A second aspect is the casting mold apparatus according to the first aspect, wherein the gas passage may have a cooling gas outlet for blowing the cooling gas in an area surrounded by the plurality of gates.

[0107] This allows for directional solidification to be achieved by cooling the area of ​​the second mold surrounded by the gates earlier and slowing the cooling of the gates.

[0108] A third aspect is the casting mold apparatus according to the first or second aspect, wherein the liquid passage may have a through-passage that passes through in a direction intersecting the direction of gravity.

[0109] This allows the first mold to be effectively cooled by the cooling liquid flowing through the through liquid passage.

[0110] A fourth aspect is a casting mold apparatus according to any one of the first to third aspects, wherein the first mold includes a core pin, and the liquid passage may have a pin liquid passage for flowing a cooling liquid into the core pin.

[0111] This allows the area through which the core pin passes to be cooled quickly.

[0112] A fifth aspect is a casting mold device according to any one of the first to fourth aspects, wherein the liquid passage has a plurality of independent liquid passages through which cooling liquid flows independently of one another, and the device may further include a valve corresponding to each of the plurality of independent liquid passages.

[0113] This allows for desirable directional solidification to be achieved by controlling the timing at which the coolant flows through each of the plurality of independent liquid passages using the valves corresponding to each of the independent liquid passages.

[0114] A sixth aspect is a casting mold apparatus according to any one of the first to fifth aspects, further comprising a cooling liquid supply source that supplies cooling liquid to the liquid passage, a valve interposed between the cooling liquid supply source and the liquid passage, and a vacuum device that, when the valve is closed, suctions the space within the liquid passage to create a vacuum within the liquid passage, and in this vacuum state, the valve opens and the cooling liquid in the cooling liquid supply source flows within the liquid passage.

[0115] In this case, the cooling liquid flows into the liquid passage all at once, enabling rapid cooling.

[0116] A seventh aspect is a casting mold apparatus according to any one of the first to sixth aspects, which may further include a valve that controls the timing at which the coolant flows through the liquid passage, and a timer that controls the timing at which the valve opens and closes over time.

[0117] In this case, the timing of opening and closing the valve is controlled by time, which enables stable casting regardless of the thermal properties of the mold itself.

[0118] A method for manufacturing a casting according to an eighth aspect includes supplying molten metal into a mold space of any one of the first to seventh casting mold devices, cooling the molten metal in the mold space with a cooling liquid flowing through the liquid passage to harden the molten metal, and removing the casting formed by the hardened molten metal from the casting mold device.

[0119] This allows the casting to be cooled more effectively by the cooling liquid flowing through the liquid passage.

[0120] A casting apparatus according to a ninth aspect includes a cooling liquid supply source that supplies cooling liquid to an inlet-side supply passage connected to the inlet of a liquid passage for cooling a casting mold, a valve interposed between the cooling liquid supply source and the outlet of the inlet-side supply passage, and a vacuum device that is connected to an outlet-side main fluid passage that is connected to the outlet of the liquid passage, and that, when the valve is closed, sucks out gas from the outlet-side main fluid passage to create a vacuum inside the outlet-side main fluid passage, and the valve opens when in the vacuum state.

[0121] In this way, the cooling passage is also evacuated by creating a vacuum in the outlet main fluid passage. By opening the valve in this state, the cooling liquid flows into the liquid passage all at once, allowing the casting to be cooled more effectively.

[0122] The above description is illustrative in all respects and is not intended to limit the scope of the present invention. It is understood that numerous variations not illustrated can be envisaged without departing from the scope of the present invention. [Explanation of symbols]

[0123] 10 Cylinder head (casting) 20 Casting mold equipment 30 Casting mold 40 Type 1 41 Cast pin 42 1st mold surface 43 Penetrating liquid passage (liquid passage) 44 Liquid passage for pin (liquid passage) 50 Type 2 52 Second mold surface 53, 54 Gas passage 53a, 53as, 54a Cooling gas outlet 55, 56 Cooling gas pipe 58 Neriko 59 Spout 70 Casting Equipment 72 Mold Controller 72t timer 80 1st coolant supply device 81 Cooling water tank (coolant supply source) 82 Valve 83 Vacuum Device

Claims

1. a cooling liquid supply source for supplying cooling liquid to an inlet supply passage connected to an inlet of a liquid passage for cooling the casting mold; a valve interposed between the coolant supply source and the outlet of the inlet-side supply passage; a vacuum device connected to an outlet-side trunk fluid passage connected to the outlet of the liquid passage, the vacuum device sucking gas from within the liquid passage while the valve is closed to create a vacuum within the liquid passage; a controller for controlling the opening and closing of the valve; Equipped with The controller causes the vacuum device to suck gas from the liquid passage while the valve is closed, and then opens the valve to introduce the cooling liquid into the liquid passage after creating a vacuum inside the liquid passage.

2. The casting apparatus according to claim 1, A plurality of the liquid passages are provided, the valves are provided corresponding to the plurality of liquid passages, The controller controls the timing of flowing the cooling liquid for each of the plurality of liquid passages.

3. The casting apparatus according to claim 1 or 2, The controller opens the valve when a predetermined time has elapsed since the vacuum device started suction operation.

4. The casting apparatus according to claim 1 or 2, The vacuum device continues its suction operation with the valve closed.

5. The casting apparatus according to claim 1 or 2, The casting apparatus further comprises a pressure gauge for detecting the pressure caused by the suction of the vacuum device.

6. a valve disposed between a cooling liquid supply source and an outlet of an inlet-side supply passage connected to an inlet of a liquid passage for cooling the casting mold is closed, and gas is sucked out of the liquid passage by a vacuum device; After creating a vacuum in the liquid passage by suction with the vacuum device, the valve is opened to introduce the cooling liquid into the liquid passage; A method for cooling a casting mold, comprising: after the cooling liquid is introduced into the liquid passage, continuing to supply the cooling liquid to the liquid passage until molding of the mold is completed.

7. 7. A method for cooling a casting mold according to claim 6, comprising: The method for cooling a casting mold further comprises detecting whether or not the gas is leaking when the gas is being sucked.

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