Core marking method for sand core

Abstract

The invention relates to a core marking method for a sand core, the sand core comprises a main body core, an auxiliary core and a connecting core, a spiral hole is formed in the combination part of the main body core and the auxiliary core, the first part of the spiral hole is arranged in the main body core, and the second part of the spiral hole is arranged in the auxiliary core; the connecting core is provided with a spiral structure; the main body core, the auxiliary core and the connecting core are all manufactured in a 3D printing mode, and the spiral hole and the spiral structure are brought out in the printing process; and the main body core and the auxiliary core are assembled, the spiral structure is screwed into the spiral hole, and core marking is carried out through limiting cooperation between the spiral structure and the spiral hole. According to the core marking method disclosed by the invention, the core marking method is simple, the core marking efficiency is high, core marking does not need to be carried out in a resin sand filling or bonding mode, and the field production efficiency and operability are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of casting technology, and in particular to a method for marking sand cores. Background Technology

[0002] In the 3D printing sand casting process, due to issues with pre-embedding of inserts or complex local structures of the casting, auxiliary cores need to be designed on the main sand core. The auxiliary core is located on the lower side of the main sand core within the mold cavity, therefore it must be pre-installed before mold flipping or core flipping. Currently, the solution is to design a reverse draft mold filling groove at the junction of the main sand core and the auxiliary core. By filling the groove with resin sand, the reverse draft mold structure can fix the auxiliary core after the resin sand hardens.

[0003] However, during on-site production, when using the reverse draft mold structure with sand filling to fix the auxiliary cores for core assembly, the time required for the molding sand to harden will increase if a large number of auxiliary cores are installed. If all the auxiliary cores on the main core are pre-filled with sand before core assembly, the requirements for the tooling and site for turning the sand cores will also increase. In addition, the molding sand needs to be compacted after filling; if the operation is not done properly, the molding sand may not harden sufficiently or be compacted properly, leading to the risk of the lower core falling off. Summary of the Invention

[0004] Therefore, it is necessary to provide a sand core forming method that can quickly form cores and has high stability, in order to address the above-mentioned technical problems.

[0005] To solve the above problems, the present invention adopts the following technical solution:

[0006] This invention discloses a method for marking sand cores. The sand core includes a main core, an auxiliary core, and a connecting core. A spiral hole is provided at the joint of the main core and the auxiliary core. The first part of the spiral hole is located in the main core, and the second part of the spiral hole is located in the auxiliary core. The connecting core has a spiral structure. The main core, the auxiliary core, and the connecting core are all manufactured using 3D printing. The spiral hole and the spiral structure are brought out during the printing process. The main core and the auxiliary core are assembled, and the spiral structure is screwed into the spiral hole. Marking is performed by the limiting fit between the spiral structure and the spiral hole.

[0007] In one embodiment, adhesive is applied to the spiral structure before it is screwed into the spiral hole.

[0008] In one embodiment, the main core is provided with a positioning groove, and the auxiliary core is provided with a positioning core head that matches the positioning groove.

[0009] In one embodiment, a horizontal first mounting surface is provided in the positioning groove, and the first part is disposed on the first mounting surface; the positioning core head is provided with a second mounting surface that matches the first mounting surface, and the second part is disposed on the second mounting surface.

[0010] In one embodiment, both the first mounting surface and the second mounting surface are horizontally arranged, and the axis of the spiral hole is vertically arranged.

[0011] In one embodiment, both the first mounting surface and the second mounting surface are inclined, and the axis of the spiral hole is vertically oriented.

[0012] In one embodiment, both the first mounting surface and the second mounting surface are inclined, and the axis of the spiral hole is perpendicular to the first mounting surface.

[0013] In one embodiment, both the first mounting surface and the second mounting surface are vertically arranged, and the axis of the spiral hole is vertical, horizontal, or inclined.

[0014] In one embodiment, the spiral hole is a tapered hole with the outer end larger than the inner end, and the spiral structure is a tapered spiral that matches the conical hole.

[0015] In one embodiment, the number of connecting cores is multiple, and the number of connecting cores is proportional to the weight of the auxiliary core.

[0016] The technical solution adopted in this invention can achieve the following beneficial effects:

[0017] The core marking method disclosed in this invention allows the connecting core and its mating spiral hole to be simultaneously brought out during the printing of the main core and auxiliary core. The core marking between the main core and auxiliary core is achieved by screwing the connecting core together. This method is simple and efficient, eliminating the need for resin sand filling or adhesive bonding, significantly improving on-site production efficiency and operability. Furthermore, the connecting core of this invention is made of sand, which is more suitable for casting than ordinary metal connectors. During the high-temperature molten metal heating process, the sand connector will not soften or deform, and can still effectively connect and support the downward-facing auxiliary core under high-temperature conditions, effectively preventing the auxiliary core from falling off or sliding into the mold cavity. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the sand core structure disclosed in an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of another optional sand core structure disclosed in an embodiment of the present invention;

[0020] Figure 3This is a schematic diagram of another optional sand core structure disclosed in an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of another optional sand core structure disclosed in an embodiment of the present invention;

[0022] Explanation of reference numerals in the attached figures:

[0023] 10-Main core, 20-Auxiliary core, 21-Positioning core head, 30-Connecting core, 40-Merging part. Detailed Implementation

[0024] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0025] It should be noted that when an element is referred to as being "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," "top," "bottom," "end," "top," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] This invention discloses a method for core marking of sand cores, such as... Figure 1 As shown, a sand core may include a main core 10 and an auxiliary core 20, wherein the auxiliary core 20 is located at the bottom of the main core 10 and faces downwards. In the foundry environment, due to various reasons, such as the main core 10 and auxiliary core 20 using different sand materials and core-making processes, the main core 10 and auxiliary core 20 cannot be directly made into a single sand core. Instead, they need to be made independently and then assembled. Because the auxiliary core 20 is located at the bottom of the main core 10 and faces downwards, it may detach from the bottom of the main core 10. Therefore, it is necessary to mark the auxiliary core 20. In this embodiment, a connecting core 30 is used to mark the auxiliary core 20 and the main core 10.

[0028] Specifically, such as Figure 1 As shown, the bottom of the main core 10 is provided with a positioning groove, and the top of the auxiliary core 20 is provided with a positioning core head 21 that matches the positioning groove. The joint 40 of the positioning groove and the positioning core head 21 can be provided with a spiral hole, wherein the first part of the spiral hole is located in the main core 10, and the second part of the spiral hole is located in the positioning core head 21. The connecting core 30 can be provided with a spiral structure that matches the spiral hole. When assembling the core, the positioning core head 21 is placed in the positioning groove and the first and second parts of the spiral hole are aligned. Then, the connecting core 30 is screwed into the spiral hole and tightened to stably connect the auxiliary core 20 to the bottom of the main core 10, thus completing the standard core assembly.

[0029] It should be noted that the main core 10, auxiliary core 20 and connecting core 30 of the present invention can all be made by 3D printing. The positioning groove and the first part of the spiral hole are brought out during the printing process of the main core 10, the positioning core head 21 and the second part of the spiral hole are brought out during the printing process of the auxiliary core 20, and the spiral structure is brought out during the printing process of the connecting core 30.

[0030] In this embodiment, the connecting portion 40 may include a first mounting surface disposed in the positioning groove and a second mounting surface disposed on the positioning core head 21. Both the first and second mounting surfaces are horizontally aligned and matched. A spiral hole passes through both the first and second mounting surfaces, with the axis of the spiral hole perpendicular to both surfaces. The first portion of the spiral hole is located on the upper side of the first mounting surface and perpendicular to it, while the second portion is located on the lower side of the second mounting surface and perpendicular to it. The connecting core 30 is screwed into the spiral hole, passes through the second and first mounting surfaces, and stably connects the main core 10 and the auxiliary core 20.

[0031] Furthermore, to improve the connection strength of the connecting core 30, a small amount of adhesive, such as a casting adhesive, can be applied to the spiral structure beforehand, and then the spiral structure can be screwed into the spiral hole and tightened. Multiple connecting cores 30 can also be used as reference cores, with the number of connecting cores 30 being proportional to the weight of the auxiliary core 20. In addition, the spiral hole can be set as a tapered hole with the outer end larger than the inner end, and the spiral structure can be set as a tapered spiral that matches the tapered hole to facilitate the screwing of the connecting core 30 into the spiral hole.

[0032] Furthermore, the connecting core 30 may be provided with a screwing operation part, which may be a screwing head located at the end of the connecting core 30, or a cross or straight screwing groove located on the bottom side of the connecting core 30. It should be noted that after the core assembly and marking core are completed, the screwing head should be cut off to be flush with the cavity surface, and the screwing groove should be filled with resin sand to be flush with the cavity surface.

[0033] In another optional embodiment of the present invention, the shape of the positioning core 21 differs from that of the above embodiment, such as... Figure 2 As shown, the first mounting surface and the second mounting surface are mutually matching inclined surfaces, and the axis of the spiral hole is vertically arranged. Specifically, the first part of the spiral hole is vertically arranged on the upper side of the first mounting surface, and the second part of the spiral hole is vertically arranged on the lower side of the second mounting surface. The connecting core 30 is screwed into the spiral hole, passes through the second mounting surface and the first mounting surface, and stably connects the main core 10 and the auxiliary core 20. In this embodiment, other settings of the sand core and the core assembly and standard core operation methods can be the same as in the above embodiments, and will not be repeated here.

[0034] In another optional embodiment of the present invention, the orientation of the spiral hole differs from that in the above embodiments, such as... Figure 3 As shown, the first mounting surface and the second mounting surface are mutually matching inclined surfaces, and the axis of the spiral hole is perpendicular to the first mounting surface / second mounting surface. Specifically, the first part of the spiral hole is located on the upper side of the first mounting surface and is perpendicular to it, while the second part is located on the lower side of the second mounting surface and is perpendicular to it. The connecting core 30 is screwed into the spiral hole, passes through the second mounting surface and the first mounting surface, and stably connects the main core 10 and the auxiliary core 20. In this embodiment, other settings of the sand core and the core assembly and standard core operation methods are the same as in the above embodiments, and will not be repeated here.

[0035] In another optional embodiment of the present invention, the shape of the positioning core 21 differs from that of the above embodiment, such as... Figure 4 As shown, the first mounting surface and the second mounting surface are mutually matching vertical surfaces, and the axis of the spiral hole is also vertically arranged. The first part of the spiral hole is located on the first mounting surface, and the second part is located on the second mounting surface. The positioning core head 21 is assembled into the positioning groove. The first mounting surface and the second mounting surface combine to form a complete spiral hole. The connecting core 30 is screwed into the spiral hole, and the connecting main core 10 and auxiliary core 20 are tightened. In this embodiment, other settings of the sand core and the core assembly and marking operations can be the same as in the above embodiments, and will not be repeated here.

[0036] Furthermore, in this embodiment, the axis of the spiral hole is not limited to being vertically set. Depending on the sand core structure, it can also be set horizontally or inclined. This embodiment does not impose any specific restrictions on this.

[0037] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0038] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for core marking of sand cores, characterized in that, The sand core includes a main core, an auxiliary core, and a connecting core. A spiral hole is provided at the joint between the main core and the auxiliary core. The first part of the spiral hole is located in the main core, and the second part of the spiral hole is located in the auxiliary core. The connecting core is provided with a spiral structure; The main core, the auxiliary core, and the connecting core are all manufactured using 3D printing, and the spiral hole and the spiral structure are brought out during the printing process. The main core and the auxiliary core are assembled, and the spiral structure is screwed into the spiral hole. The standard core is formed by the limiting fit between the spiral structure and the spiral hole.

2. The core-marking method for sand cores according to claim 1, characterized in that, Before screwing the spiral structure into the spiral hole, apply glue to the spiral structure.

3. The core-marking method for sand cores according to claim 1, characterized in that, The main core is provided with a positioning groove, and the auxiliary core is provided with a positioning core head that matches the positioning groove.

4. The core-marking method for sand cores according to claim 3, characterized in that, The positioning groove is provided with a horizontal first mounting surface, and the first part is provided on the first mounting surface; the positioning core is provided with a second mounting surface that matches the first mounting surface, and the second part is provided on the second mounting surface.

5. The core-marking method for sand cores according to claim 4, characterized in that, Both the first mounting surface and the second mounting surface are horizontally arranged, and the axis of the spiral hole is vertically arranged.

6. The core-marking method for sand cores according to claim 4, characterized in that, Both the first mounting surface and the second mounting surface are inclined, and the axis of the spiral hole is vertical.

7. The core-marking method for sand cores according to claim 4, characterized in that, Both the first mounting surface and the second mounting surface are inclined, and the axis of the spiral hole is perpendicular to the first mounting surface.

8. The core-marking method for sand cores according to claim 3, characterized in that, Both the first mounting surface and the second mounting surface are vertically arranged, and the axis of the spiral hole is vertical, horizontal, or inclined.

9. The core-marking method for sand cores according to any one of claims 1 to 8, characterized in that, The spiral hole is a tapered hole with the outer end larger than the inner end, and the spiral structure is a tapered spiral that matches the conical hole.

10. The core marking method for sand cores according to claim 9, characterized in that, The number of connecting cores is multiple, and the number of connecting cores is proportional to the weight of the auxiliary core.

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