Method for suppressing deformation of cast raw materials

Abstract

To provide a method for suppressing deformation of a cast material that effectively suppresses deformation of the cast material by die casting. [Solution] The method for suppressing deformation of a cast material involves setting one or more predicted deformation positions in a die-cast material where deformation is expected, and installing a deformation suppression jig in the direction of thermal contraction at the predicted deformation positions during the cooling of the material. This method effectively suppresses deformation of a die-cast material during the cooling process.

Description

Technical Field

[0001] The present invention relates to a method for suppressing deformation of as-cast rough materials.

Background Art

[0002] A casting method called die casting can produce complex and precise parts that could not be manufactured by conventional casting methods. Die casting is a casting method in which materials are injected into a mold at high speed and high pressure. In addition, a casting method called gigacasting, which is a development of die casting, has been developed to cast large parts for vehicles having large and complex shapes in one batch.

[0003] Normally, as-cast rough materials are deformed by thermal shrinkage during the cooling process. Therefore, a correction process for correcting the deformation of the rough materials is required. Here, for products manufactured by complex and precise die casting or gigacasting, it is difficult to correct the rough materials, and problems such as cracking are likely to occur. In addition, the correction process includes a process of raising the temperature of the rough materials. Since products manufactured by gigacasting are often large, compared with ordinary casting products, more energy is required for the temperature-raising process of the correction process, and the manufacturing cost increases.

[0004] Patent Document 1 discloses a hot distortion correction device for die-cast products, which includes a processing material clamping means composed of an upper mold and a lower mold, a load adjustment means for balancing the load of the upper mold, a pressurizing means, a forced convection fan, and a heater.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The hot distortion correction device for die-cast products described in Patent Document 1 applies the desired pressure to the entire material by using a load adjustment means to prevent the weight of the upper mold from being applied to the material being processed when applying the corrective pressure. Furthermore, the above hot distortion correction device for die-cast products heats the material uniformly by circulating the atmosphere heated by a heater inside the furnace using a forced convection fan. As a result, the above hot distortion correction device for die-cast products can correct even complex shapes of the material being processed through uniform pressurization and heating.

[0007] However, the above-mentioned hot distortion correction device for die-cast products requires energy to heat the die-cast product during the correction process. Furthermore, if the above-mentioned hot distortion correction device for die-cast products is applied to the correction process of raw material using Gigacast, the correction equipment becomes larger, and a large amount of energy is required for heating, resulting in higher manufacturing costs.

[0008] In view of the above-mentioned problems, this disclosure provides a method for suppressing deformation of a cast raw material that effectively suppresses deformation of the raw material cast by die casting. [Means for solving the problem]

[0009] A method for suppressing deformation of a cast raw material according to one aspect of the present disclosure involves setting one or more predicted deformation positions in a raw material cast by die casting where deformation of the raw material is predicted, and installing a deformation suppression jig in the direction of thermal contraction at the predicted deformation positions when the raw material is cooled.

[0010] In the above method for suppressing deformation of a cast raw material, the deformation suppression jig may be in surface contact with the raw material at the predicted deformation position.

[0011] In the above method for suppressing deformation of cast raw materials, the deformation suppression jig may have high thermal conductivity.

[0012] In the above method for suppressing deformation of cast raw materials, the raw material may be a large vehicle component manufactured by Gigacast. [Effects of the Invention]

[0013] According to this disclosure, a method for suppressing deformation of a cast material can be provided that effectively suppresses the deformation of the cast material. [Brief explanation of the drawing]

[0014] [Figure 1] This is a schematic diagram illustrating the method for suppressing deformation of a cast raw material according to Embodiment 1. [Figure 2] This is a process diagram showing the work steps of the method for suppressing deformation of casting material according to Embodiment 1. [Figure 3] This is a schematic diagram of the deformation simulation results of the raw material according to Embodiment 1. [Modes for carrying out the invention]

[0015] The present invention will be described below through embodiments of the invention, but the invention claimed is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential as means of solving the problem. For clarity of explanation, the following descriptions and drawings have been omitted and simplified as appropriate. In each drawing, the same elements are denoted by the same reference numerals, and redundant explanations have been omitted where necessary.

[0016] <Embodiment 1> Embodiment 1 relates to die casting, one of the casting methods. Die casting is a casting method in which material is injected at high speed and high pressure during the casting process. Die casting is used to manufacture parts with complex shapes, such as computer components, by casting.

[0017] Further, Embodiment 1 relates to gigacasting, which is an evolution of die casting. Gigacasting is a casting method for manufacturing large parts by injecting material into a mold at a higher pressure than die casting. Gigacasting can integrally form a structure that was divided into multiple parts in die casting. Therefore, gigacasting is used for manufacturing large vehicle parts or large antenna parts that are large and have complex shapes. Here, gigacasting is treated as one method of die casting.

[0018] FIG. 1 is a schematic diagram showing a method for suppressing deformation of a rough casting according to Embodiment 1. FIG. 1 shows the positional relationship between the rough casting and the deformation suppression jig 10 from above. Here, the rough casting refers to a preform that has been formed by casting and is before the correction process or the finishing process. The rough casting 1 is cast by die casting or gigacasting. The rough casting 1 is, for example, a large vehicle part or a large antenna part. In FIG. 1, the rough casting 1 is a large vehicle part manufactured by gigacasting.

[0019] In FIG. 1, the rough casting 1 is taken out of the mold after casting by gigacasting and is in a cooled state. The rough casting 1 is deformed due to thermal contraction during cooling. Deformation is also called strain. Deformation is a major cause of reduced manufacturing accuracy.

[0020] The deformation suppression jig 10 is used to suppress deformation of the rough casting 1 due to thermal contraction. The deformation suppression jig 10 includes a fixing mechanism (not shown) such as a block or a strut. The deformation suppression jig 10 includes a contact portion 11 that contacts the rough casting 1. The contact portion 11 is supported on the deformation suppression jig 10 by the fixing mechanism.

[0021] The deformation suppression jig 10 is installed in the thermal contraction direction at the predicted deformation position of the rough material 1. More specifically, the deformation suppression jig 10 is installed such that the contact portion 11 contacts in the thermal contraction direction at the predicted deformation position of the rough material 1. The predicted deformation position is a position on the rough material 1 where deformation due to thermal contraction is predicted. The predicted deformation position is determined as one or more by simulation or test based on the structure of the rough material 1. According to this, the deformation suppression jig 10 can apply a reaction force against the deformation due to thermal contraction and suppress the deformation of the rough material 1.

[0022] The deformation suppression jig 10 may include a hook-shaped contact portion 11 applied to the rough material 1. According to this, the deformation suppression jig 10 can apply the contact portion 11 to the rough material 1 and suppress the deformation of the rough material 1 in the direction away from the deformation suppression jig 10. The deformation suppression jig 10 may include a contact portion 11 having a shape that covers a part of the rough material 1. According to this, the deformation suppression jig 10 can suppress the deformation by covering the protrusion portion or the like of the rough material 1. Further, the deformation suppression jig 10 may be plate-shaped. According to this, the deformation suppression jig 10 is installed at a location that becomes a groove of the rough material 1 and can suppress the deformation such that the groove is crushed.

[0023] The contact portion 11 of the deformation suppression jig 10 may be designed to contact the rough material 1 in a surface-to-surface manner. Specifically, the contact portion 11 of the deformation suppression jig 10 has a shape with a surface along the outer shape of the predicted deformation position of the rough material 1. In this case, at the predicted deformation position, the rough material 1 and the contact portion 11 of the deformation suppression jig 10 are in surface-to-surface contact. According to this, the deformation suppression jig 10 can disperse and apply the reaction force against the deformation of the rough material 1 to the predicted deformation position and preferably suppress the deformation of the rough material 1.

[0024] The deformation suppression jig 10 may be installed to cover multiple predicted deformation positions. For example, the deformation suppression jig 10 may have a rod-shaped connecting part and be positioned to cover two predicted deformation positions that are symmetrically located on the raw material 1. In this case, the deformation suppression jig 10 can efficiently suppress the deformation of the raw material 1 by having the forces generated by the deformation at symmetrical positions of the raw material 1 support each other. Alternatively, the deformation suppression jig 10 may have a triangular or three-pronged connecting part and be positioned to cover three predicted deformation positions on the raw material 1. In this case, the deformation suppression jig 10 can efficiently suppress the deformation of the raw material 1 by having the forces generated by the deformation at three positions of the raw material 1 support each other.

[0025] The deformation suppression jig 10 may have high thermal conductivity. This allows the deformation suppression jig 10 to efficiently cool the raw material 1 without hindering cooling at the point of contact with the raw material 1. Furthermore, the deformation suppression jig 10 reduces uneven cooling of the raw material 1 by suppressing changes in the cooling efficiency of the raw material 1 at the point of contact, thereby suppressing damage such as cracking of the raw material 1 due to temperature differences. Note that only the contact portion 11 may have high thermal conductivity.

[0026] In Figure 1, the raw material 1 is fitted with a first deformation suppression jig 10a, a second deformation suppression jig 10b, a third deformation suppression jig 10c, and a fourth deformation suppression jig 10d. The first deformation suppression jig 10a is installed at the upper left (-x, +y direction) end of the raw material 1 when viewed from above. The first deformation suppression jig 10a overlaps the predicted deformation area indicated by the dashed line, and the first contact portion 11a is installed so as to support the predicted deformation area from the outside (-x direction). The second deformation suppression jig 10b is installed at the upper right (+x, +y direction) end of the raw material 1 when viewed from above. The second deformation suppression jig 10b overlaps the predicted deformation area indicated by the dashed line, and the second contact portion 11b is installed so as to support the predicted deformation area from the outside (+x direction).

[0027] The third deformation suppression jig 10c is installed next to the protrusion on the lower left (-x, -y direction) of the raw material 1 when viewed from above. The third deformation suppression jig 10c is installed so that the third contact portion 11c supports the protrusion on the lower left (-x, -y direction) of the raw material 1, which is the predicted deformation location, from the inside (+x direction). The fourth deformation suppression jig 10d is installed next to the protrusion on the lower right (+x, -y direction) of the raw material 1 when viewed from above. The fourth deformation suppression jig 10d is installed so that the fourth contact portion 11d supports the protrusion on the lower right (+x, -y direction) of the raw material 1, which is the predicted deformation location, from the inside (-x direction).

[0028] According to this, the first deformation suppression jig 10a, the second deformation suppression jig 10b, the third deformation suppression jig 10c, and the fourth deformation suppression jig 10d each support the predicted deformation area of ​​the raw material 1 from the direction of thermal shrinkage. Therefore, the deformation suppression jig 10 can suppress deformation of the raw material 1 due to thermal shrinkage during the cooling process. As a result, the deformation suppression jig 10 can reduce the straightening process after the cooling process.

[0029] Furthermore, the third deformation suppression jig 10c and the fourth deformation suppression jig 10d may be connected by a rod-shaped connecting part. In this case, the third deformation suppression jig 10c and the fourth deformation suppression jig 10d mutually support the forces acting on the deformation of the raw material 1 in opposing directions, thereby efficiently suppressing the deformation of the raw material 1.

[0030] Figure 2 is a process diagram showing the work steps of the deformation suppression method for casting rough material according to Embodiment 1. The work steps of the deformation suppression method for casting rough material according to Embodiment 1 include steps S11 to S16.

[0031] In step S11, one or more predicted deformation positions are set where deformation of the raw material 1 is predicted. The predicted deformation positions of the raw material 1 are set by the computer, for example, by acquiring structural information of the raw material 1 and performing a simulation. Alternatively, the predicted deformation positions of the raw material 1 may be set based on deformation information obtained by testing the raw material 1. Here, the computer may acquire deformation information during the prototyping of the raw material 1 using sensors. The computer may also set the predicted deformation positions of the raw material 1 based on the acquired deformation information. The business operator may also acquire deformation information during the prototyping of the raw material 1 by measuring it. The business operator may also set the predicted deformation positions of the raw material 1 based on the acquired deformation information.

[0032] Figure 3 is a schematic diagram of the deformation simulation results of the raw material 1 according to Embodiment 1. In Figure 3, deformation occurs in the raw material 1. Specifically, the upper left side wall (-x, +y direction) of the raw material 1, as viewed from the top, is deformed by tilting outward (-x direction), as indicated by the white arrow. Also, the upper right side wall (+x, +y direction) of the raw material 1, as viewed from the top, is deformed by tilting outward (+x direction), as indicated by the white arrow.

[0033] The protrusion on the lower left (-x, -y direction) of the raw material 1, as viewed from the top, is deformed by tilting inward (+x direction), as indicated by the white arrow. The protrusion on the lower right (+x, -y direction) of the raw material 1, as viewed from the top, is also deformed by tilting inward (-x direction), as indicated by the white arrow. Furthermore, along with the deformation of the protrusions on the lower left (-x, -y direction) and lower right (+x, -y direction) of the raw material 1, the center of the lower part (-y direction) is deformed so that the bottom edge shifts to the right (+x direction).

[0034] Here, the computer obtains deformation information of the raw material 1 from the deformation simulation results shown in Figure 3. Based on the deformation information of the raw material 1, the computer determines four locations as major deformation points: the upper left (-x, +y direction) and upper right (+x, +y direction) side walls when viewed from above, and the lower left (-x, -y direction) and lower right (+x, -y direction) protrusions, and sets them as predicted deformation positions. The computer also determines the direction of thermal contraction at these four predicted deformation positions. Based on this, the computer can determine the installation position of the deformation suppression jig 10.

[0035] Next, in step S12, the manufacturing apparatus casts the raw material 1. Here, the manufacturing apparatus is a die-casting apparatus. The manufacturing apparatus may also be a gigacasting apparatus. In step S13, the manufacturing apparatus removes the raw material 1 from the mold. In this way, the manufacturing apparatus can produce heated raw material 1.

[0036] In step S14, the manufacturing apparatus installs the deformation suppression jig 10 at the predicted deformation position of the raw material 1. The business operator may also install the deformation suppression jig 10 at the predicted deformation position of the raw material 1. Note that the raw material 1 in step S14 is before cooling. In step S15, the manufacturing apparatus cools the raw material 1. The raw material 1 may be cooled by natural heat dissipation or by submersion in water. Alternatively, the raw material 1 may be cooled by air cooling. In step S15, the deformation suppression jig 10 installed at the predicted deformation position of the raw material 1 suppresses deformation of the raw material 1 due to thermal shrinkage during cooling.

[0037] In step S16, the manufacturing apparatus removes the deformation suppression jig 10 from the raw material 1. The operator may also remove the deformation suppression jig 10 from the raw material 1. Since the deformation of the raw material 1 cooled using the deformation suppression jig 10 is suppressed, it can be treated as a die-cast product at the stage when the deformation suppression jig 10 is removed.

[0038] As described above, the method for suppressing deformation of the casting material, including steps S11 to S16, enables the manufacturing apparatus to produce die-cast products with suppressed deformation due to thermal shrinkage. Therefore, the manufacturing apparatus using the method for suppressing deformation of the casting material of this embodiment can reduce the straightening process after the cooling process in the production of die-cast products. Furthermore, by reducing the straightening process after the cooling process, the costs associated with introducing and operating large straightening equipment can be reduced in the production of complex and large gigacast products.

[0039] Step S11 only needs to be completed before the start of step S14. Therefore, the order of processing for step S11 may be swapped with at least one of steps S12 and S13. Also, step S11 may be processed simultaneously with at least one of steps S12 and S13.

[0040] Here, the effectiveness of the deformation suppression method for cast raw materials according to this embodiment (see Figure 1) was confirmed, and the maximum deformation amount of raw material 1 was 1 mm. On the other hand, the maximum deformation amount of the comparison raw material was 3 mm. The comparison raw material was a raw material cooled by a normal method without using the deformation suppression jig 10. In other words, the deformation suppression method for cast raw materials according to this embodiment reduced the amount of deformation of the raw material during the cooling process by 67%. That is, the deformation suppression method for cast raw materials according to this embodiment can suitably suppress the deformation of raw materials cast by die casting during the cooling process.

[0041] It should be noted that the present invention is not limited to the embodiments described above, and can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0042] 1. Raw material 10. Deformation suppression jig 10a First deformation suppression jig 10b Second deformation suppression jig 10c Third deformation suppression jig 10d Fourth deformation suppression jig 11 Contact part 11a First contact portion 11b Second contact portion 11c Third contact part 11d Fourth contact part

Claims

1. In a raw material cast by die-casting, One or more predicted deformation positions are set where deformation of the raw material is predicted. During the cooling of the raw material, a deformation suppression jig is installed in the direction of thermal contraction at the predicted deformation position. A method for suppressing deformation of cast raw materials.

2. The method for suppressing deformation of a cast rough material according to claim 1, wherein the deformation suppression jig is in surface contact with the rough material at the predicted deformation position.

3. The deformation suppression jig has high thermal conductivity, the method for suppressing deformation of a cast raw material according to claim 1 or 2.

4. The method for suppressing deformation of a cast raw material according to claim 1 or 2, wherein the raw material is a large vehicle component manufactured by Gigacast.

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