A gating system for 3D printed sand molds

Abstract

The application provides a pouring system of 3D printing sand mold, comprising a support frame, a sand carrying frame, a cover mechanism, a matching plate and a driving device. The sand carrying frame is reversibly arranged on the support frame and has open upper and lower ends. The cover mechanism can cover the open upper end of the sand carrying frame. The matching plate is detachably connected to the open lower end of the sand carrying frame. The matching plate is provided with first and second holes through which the sprue cup and the riser cup protruding from the sand mold can pass. The driving device is used to drive the sand carrying frame to reverse. The sand carrying frame, the cover mechanism and the matching plate form a box body to load the sand mold and sand particles. The sand mold is loaded in the box body formed by the sand carrying frame, the cover mechanism and the matching plate, and the sand mold is fixed by filling sand and gravel therein. The sand particles exert external force on the sand mold from all directions, so that the occurrence of flash burrs and product deformation caused by the metal liquid entering the sand particles between the faults due to the layer fault phenomenon is reduced as much as possible.

Description

Technical Field

[0001] This invention relates to the field of 3D printing equipment technology, and more specifically to a casting system for 3D printing sand molds. Background Technology

[0002] Sand mold 3D printing stacks and bonds sand particles layer by layer to achieve complex shapes. However, sand mold 3D printing also sometimes suffers from layer breakage, where adjacent layers of sand particles do not bond well. When the sand mold is subsequently filled with molten metal at high temperature, the molten metal enters between the poorly bonded sand particles, causing the sand mold to expand and resulting in burrs and flash. This increases subsequent processing time and, in severe cases, can affect the shape and performance of the product. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the present invention provides a 3D printed sand mold casting system, which can solve or at least alleviate one or more of the above-mentioned problems and other problems existing in the prior art.

[0004] This invention provides a casting system for 3D printed sand molds, comprising: a support frame; a sand-carrying frame, rotatably mounted on the support frame with open top and bottom ends; a covering mechanism, capable of covering the open top end of the sand-carrying frame; a mating plate, detachably connected to the open bottom end of the sand-carrying frame, having a first hole and a second hole for accommodating a protruding pouring cup and riser cup from the sand mold; and a driving device for driving the sand-carrying frame to rotate; the sand-carrying frame, the covering mechanism, and the mating plate constitute a housing for loading the sand mold and sand particles.

[0005] Preferably, it further includes two symmetrically arranged flipping mechanisms, and the support frame includes two parallel support members, the upper ends of which are each provided with a first toothed rack along their length.

[0006] The flipping mechanism includes:

[0007] A sliding member, slidably mounted on the support member, is slidable along the length of the support member and has a through third hole thereon; and

[0008] The rotating shaft has one end connected to the outer wall of the sand-carrying frame, and the other end passes through the third hole of the sliding member on the same side and is connected to the first gear.

[0009] The first gear can be suspended or meshed with the first rack on the same side. The rotating shaft is rotatably engaged with the third hole. The driving device is used to drive the sliding member to move along the length direction of the support member.

[0010] Preferably, a second rack along its length is provided on the opposite side of each of the two supports; a second gear is rotatably sleeved on the sliding member, the second gear meshing with the second rack, and the driving device is used to drive the second gear to rotate.

[0011] Preferably, it further includes a connecting block, the two ends of which are respectively connected to the two sliding members, and a third gear is rotatably sleeved on the sliding member. The third gear and the second gear are coaxially fixedly connected, and the diameter of the second gear is smaller than that of the third gear.

[0012] The driving device includes:

[0013] The driving component is slidably mounted on the connecting block, and has third toothed racks on both sides; and

[0014] An electric actuator, the output end of which is connected to the driving component;

[0015] The third rack meshes with the third gear on the same side.

[0016] Preferably, a guide ring is fitted around the upper outer periphery of the sand-carrying frame;

[0017] The closing mechanism includes:

[0018] The cover frame is slidably sleeved outside the guide ring, and a guide opening is provided on its side wall. A limiting ring that can abut against the guide ring is connected to its inner wall.

[0019] The outer cover plate can slide laterally onto the port of the cover frame, and has a first locking hole thereon;

[0020] The inner partition has a second locking hole at one end and can slide laterally through the guide opening to be inserted into the cover frame, parallel to the outer cover plate. It has multiple material discharge notches.

[0021] The locking plate has two ends that slide through the first locking hole and the second locking hole, respectively.

[0022] The locking plate is provided with limiting blocks at all four corners, and all four limiting blocks can abut against the outer cover plate; when the sand-carrying frame is flipped, the locking plate can abut against the driving component.

[0023] Preferably, the sliding member has a pressing groove on the side facing the cover frame, and the side wall contours of the pressing groove are two parallel involutes. A pressing rod is connected to the side of the cover frame facing the sliding member, and the end of the pressing rod away from the cover frame is inserted into the pressing groove. The pressing rod and the pressing groove are in clearance fit.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] In this invention, a box is formed by a sand-carrying frame, a cover mechanism, and a mating plate to load the sand mold. The sand mold is fixed by filling it with gravel. The sand particles apply external force to the sand mold from all directions, minimizing the occurrence of molten metal entering between the sand particles due to the layering phenomenon, forming burrs and product deformation. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0027] Figure 1 This is a perspective view of a 3D printed sand mold casting system according to an embodiment of the present invention;

[0028] Figure 2 for Figure 1 Enlarged view of point A;

[0029] Figure 3 for Figure 1 Another 3D image;

[0030] Figure 4 for Figure 1 Another 3D image;

[0031] Figure 5 for Figure 1 A three-dimensional diagram of the fitting mechanism and the sand-carrying frame;

[0032] Figure 6 for Figure 5 Another stereoscopic view (left view);

[0033] Figure 7 for Figure 5 A sectional view;

[0034] Figure 8 for Figure 5 Top view (without outer cover and inner partition).

[0035] Figure label:

[0036] 10. Support component; 11. First rack; 12. Second rack;

[0037] 20. Sand-carrying frame; 21. Guide ring;

[0038] 30. Covering mechanism; 31. Covering frame; 311. Guide opening; 312. Limiting ring; 313. Pressing rod; 32. Outer cover plate; 321. First locking hole; 33. Inner partition plate; 331. Second locking hole; 332. Material discharge notch; 34. Locking plate; 341. Limiting block;

[0039] 40. Mating plate; 41. First hole; 42. Second hole;

[0040] 50. Drive unit; 51. Drive component; 52. Electric actuator;

[0041] 60. Tilting mechanism; 61. Sliding component; 611. Third hole; 612. Second gear; 613. Third gear; 614. Pressing groove; 62. Rotating shaft; 63. First gear; 64. Connecting block;

[0042] 70. Metal molten metal injection port. Detailed Implementation

[0043] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0044] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0045] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0046] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0047] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0048] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0049] See Figures 1 to 8 This embodiment provides a casting system for 3D printed sand molds, including: a support frame, a sand-carrying frame 20, a cover mechanism 30, a mating plate 40, and a driving device 50.

[0050] The sand-carrying frame 20 is rotatably mounted on the support frame, with open ends. The sand-carrying frame 20 can be flipped to invert its top and bottom. The closing mechanism 30 can close onto the open upper end of the sand-carrying frame 20, thus sealing the upper end of the sand-carrying frame 20. The mating plate 40 is detachably connected to the open lower end of the sand-carrying frame 20, sealing the lower end of the sand-carrying frame 20. The mating plate 40 has a first hole 41 and a second hole 42 that allow the protruding pouring cup and riser cup on the sand mold to pass through. Specifically, the distance between the protruding pouring cup and riser cup on sand molds of different sizes is different (in 3D printed sand molds, the pouring cup and riser cup are directly fixed to the sand mold). Therefore, the size and distance of the first hole 41 and the second hole 42 on the mating plate 40 are different. Thus, the mating plate 40 is replaceable. The mating plate 40 and the sand-carrying frame 20 can be connected by bolts or by abutment.

[0051] The drive unit 50 is used to drive the sand-carrying frame 20 to rotate. The sand-carrying frame 20, the covering mechanism 30, and the mating plate 40 constitute a box for loading the sand mold and sand particles. In use, the end of the sand mold with the pouring cup and riser cup faces the mating plate 40 (this end is 3D printed with protruding pouring cup and riser cup on a flat surface). Then, the pouring cup and riser cup pass through the first hole 41 and the second hole 42 on the mating plate 40, while the end face of the sand mold is in contact with the mating plate 40. At this time, the entire sand mold is inverted. Then, sand particles are filled into the sand-carrying frame 20, using the sand particles to surround the entire sand mold, thereby fixing the sand mold. Finally, the covering mechanism 30 is used to cover the open end of the sand-carrying frame 20. After the drive unit 50 drives the sand-carrying frame 20 to rotate, the inverted sand mold rotates back, with the pouring cup and riser cup facing upwards, and then pouring can be performed. The reason for using sand particles for fixation is as follows: Under the clamping of the upper and lower cover mechanisms 30 and the mating plate 40, the sand mold in the middle can be fixed, while the sand mold's perimeter needs to be filled with sand particles for further reinforcement. Furthermore, the outer surface of the sand mold is not necessarily flat; it may be irregularly shaped. Sand particles can effectively handle sand molds of various shapes. Also, sand particles are very common in the 3D printing industry and are readily available. Moreover, the location of layer breaks in the sand mold varies. By filling the space with sand particles and then fixing the sand mold, external force can be applied to the sand mold from various directions, minimizing the occurrence of molten metal entering between the broken sand particles, forming burrs and causing product deformation. The first hole 41 and the second hole 42 on the mating plate 40 can position the sand mold so that after the sand-carrying frame 20 is flipped, the pouring cup is positioned directly below the molten metal inlet 70.

[0052] In one embodiment, the system further includes two symmetrically arranged flipping mechanisms 60. The support frame includes two parallel support members 10, each with a first rack 11 extending along its length at its upper end. The two first racks 11 are parallel to each other. The flipping mechanisms 60 are located between the support members 10 and the sand-carrying frame 20.

[0053] The flipping mechanism 60 includes a slider 61 and a rotating shaft 62.

[0054] The sliding member 61 is slidably mounted on the support member 10 and can slide along the length of the support member 10. A through third hole 611 is provided on it. Specifically, the sliding member 61 can be connected to the support member 10 on the same side by means of a guide rail, or it can be achieved by opening a dovetail groove on the sliding member 61 and setting a dovetail block on the support member 10 that slides and engages with the dovetail groove.

[0055] One end of the rotating shaft 62 is connected to the outer wall of the sand-carrying frame 20, and the other end of the rotating shaft 62 passes through the third hole 611 of the sliding member 61 on the same side and is connected to the first gear 63. The first gear 63 can be suspended or meshed with the first rack 11 on the same side. The driving device 50 is used to drive the sliding member 61 to move along the length direction of the support member 10. The rotating shaft 62 is rotatably engaged with the third hole 611.

[0056] In this embodiment, under the drive of the drive device 50, when the first gear 63 is suspended, the sliding member 61, together with the rotating shaft 62 and the sand-carrying frame 20, moves along the length direction of the support member 10 until the first gear 63 meshes with the first rack 11. At this time, the first gear 63 rotates, thereby driving the sand-carrying frame 20 to rotate, so as to realize the flipping of the sand-carrying frame 20.

[0057] In one embodiment, a second rack 12 along its length is provided on the opposite side of each of the two support members 10. A second gear 612 is rotatably sleeved on the sliding member 61, and the second gear 612 meshes with the second rack 12. The driving device 50 is used to drive the second gear 612 to rotate.

[0058] In this embodiment, driven by the driving device 50, the second gear 612 rotates forward and backward along the second rack 12, thereby driving the sliding member 61 to move.

[0059] In one embodiment, a connecting block 64 is further included. The two ends of the connecting block 64 are respectively connected to two sliding members 61. A third gear 613 is rotatably sleeved on the sliding member 61. The third gear 613 and the second gear 612 are coaxially fixedly connected. The diameter of the second gear 612 is smaller than that of the third gear 613.

[0060] The drive unit 50 includes a drive element 51 and an electric actuator 52.

[0061] The driving component 51 is slidably mounted on the connecting block 64, and has a third toothed rack on both sides. Specifically, the connecting block 64 has a guide groove, and the driving component 51 slides in the guide groove. The driving component 51 is U-shaped in the figure, so there are two guide grooves to accommodate the two arms of the driving component 51.

[0062] The output end of the electric actuator 52 is connected to the drive unit 51. The third rack meshes with the third gear 613 on the same side.

[0063] In this embodiment, the sand-carrying frame 20 completes its rotation after one revolution of the first gear 63. Typically, the first gear 63 is not very large. Setting the third gear 613 to be larger than the second gear 612 reduces the load on the electric actuator 52 by changing the transmission ratio, thus stabilizing the device's operation and extending its service life.

[0064] In one embodiment, a guide ring 21 is fitted around the upper outer periphery of the sand-carrying frame 20.

[0065] The closing mechanism 30 includes a closing frame 31, an outer cover plate 32, an inner partition plate 33, and a locking plate 34.

[0066] The cover frame 31 is slidably fitted onto the guide ring 21 in a vertical direction. A guide opening 311 is provided on its side wall, and a limiting ring 312, which abuts against the guide ring 21, is connected to its inner wall. The limiting ring 312 and the guide ring 21 prevent the cover frame 31 from detaching from the sand-carrying frame 20. Furthermore, two guide rings 21 can be provided, one at the upper end and one at the lower end of the sand-carrying frame 20, to prevent the cover frame 31 from detaching from the sand-carrying frame 20 after sliding downwards.

[0067] The outer cover plate 32 can slide laterally onto the port of the cover frame 31, and has a first locking hole 321. Specifically, the size of the outer cover plate 32 is roughly the same as the size of the upper port of the cover frame 31. The outer cover plate 32 is connected to the cover frame 31 by a guide rail, so that pushing and pulling the outer cover plate 32 can open and close the upper port of the cover frame 31.

[0068] One end of the inner partition 33 has a second locking hole 331, and the other end of the inner partition 33 can slide laterally through the guide opening 311 and be inserted into the cover frame 31, parallel to the outer cover plate 32. Multiple material discharge notches 332 are provided on the inner partition 33. Both ends of the locking plate 34 slide through the first locking hole 321 and the second locking hole 331, respectively. Each of the four corners of the locking plate 34 has a limiting block 341, and all four limiting blocks 341 can abut against the outer cover plate 32. When the sand-carrying frame 20 is flipped, the locking plate 34 can abut against the driving component 51.

[0069] In this embodiment, as Figure 1 When the sand-carrying frame 20 is opened (at this time, both the outer cover plate 32 and the inner partition plate 33 are pulled out), an inverted sand mold is placed into the sand-carrying frame 20. At this time, the lower end of the locking plate 34 hangs naturally into the second locking hole 331 under the action of gravity. Pulling the locking plate 34 upward pushes the inner partition plate 33 into the cover frame 31. The inner partition plate 33 moves along the groove on the inner wall of the cover frame 31. The inner partition plate 33 slides and engages with the groove on the inner wall of the cover frame 31. Then, sand is injected from the upper part of the cover frame 31 until the sand submerges the sand mold below the inner partition plate 33 and gradually submerges the inner partition plate 33 before overflowing from the upper end of the cover frame 31. Then, the outer cover plate 32 is pushed to close the upper end of the cover frame 31. At this time, the outer cover plate 32 pushes away the excess sand accumulated above the cover frame 31, ensuring that the cover frame 31 and the sand-carrying frame 20 are filled with sand. It should be noted that the device for adding sand to the cover frame 31 can be a pipe (not shown in the figure). As the drive device 50 drives, the sand-carrying frame 20 flips. The entire sand-carrying frame 20 tilts forward and then completes the flip. Under the action of gravity, the outer cover plate 32 and the inner partition plate 33 always keep the sand in the entire cover frame 31 from leaking.

[0070] When the sand-carrying frame 20 is flipped, under the action of gravity, the locking plate 34 slides down along the first locking hole 321 and the locking plate 34 disengages from the second locking hole 331. At this time, the driving component 51 moves to the locking plate 34 and abuts against the sliding locking plate 34. At this time, the pouring cup is located below the molten metal pouring port 70. As the molten metal enters the sand mold from the pouring cup, the pouring is completed.

[0071] Next, after the molten metal in the sand mold has cooled down, the locking plate 34 and the sand-carrying frame 20 move at the same speed. However, the driving component 51 moves faster because the diameter of the second gear 612 is smaller than that of the third gear 613. As a result, the driving component 51 pushes the locking plate 34, thereby causing the outer cover plate 32 to open the port of the cover frame 31. The sand particles flow downward from the cover frame 31, and the sand in the sand-carrying frame 20 also flows downward after passing through multiple material dropping notches 332 on the inner partition plate 33. The sand mold is blocked by the inner partition plate 33, thus preventing the sand mold from detaching from the sand-carrying frame 20.

[0072] Then, the electric actuator 52 of the drive device 50 (here, a multi-stage electric actuator 52) retracts, and the first gear 63 re-engages with the first rack 11 as the sand-carrying frame 20 retracts, causing the sand-carrying frame 20 to flip back. Simultaneously, under gravity, the outer cover plate 32 slides back to close the cover frame 31, and the locking plate 34 re-inserts into the second locking hole 331 on the inner partition plate 33. Then, pulling the locking plate 34 simultaneously pulls out the outer cover plate 32 and the inner partition plate 33, allowing the sand mold inside the sand-carrying frame 20 to be removed. In this embodiment, automatic removal of sand particles from the sand-carrying frame 20 is achieved, facilitating automation.

[0073] In one embodiment, a pressing groove 614 is provided on the side of the sliding member 61 facing the cover frame 31. The side wall contours of the pressing groove 614 are two parallel involutes. A pressing rod 313 is connected to the side of the cover frame 31 facing the sliding member 61. The end of the pressing rod 313 away from the cover frame 31 is inserted into the pressing groove 614, and the pressing rod 313 and the pressing groove 614 are in clearance fit.

[0074] In this embodiment, as the cover frame 31 rotates along with the sand-carrying frame 20, the clamping rod 313 moves along the clamping groove 614. That is, the movement trajectory of the clamping rod 313 is an involute. The clamping rod 313 spirals forward along the involute trajectory and gradually approaches the axis of the rotating shaft 62, thereby increasing the overlap between the cover frame 31 and the sand-carrying frame 20. The outer cover plate 32 moves closer to the sand-carrying frame 20, thereby compacting the sand particles in the sand-carrying frame 20 and the cover frame 31, and further locking the internal sand mold.

[0075] Numerous specific details are set forth in this specification. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A gating system for a 3D printed sand mold, characterized in that, The 3D printing sand mold pouring system comprises a support frame, a sand carrying frame (20) reversibly arranged on the support frame and having open upper and lower ends, a cover mechanism (30) capable of covering the open upper end of the sand carrying frame (20), a matching plate (40) detachably connected to the open lower end of the sand carrying frame (20) and having first and second holes (41 and 42) formed therein and capable of allowing a sprue cup and a riser cup protruding from a sand mold to pass therethrough, and a driving device (50) for driving the sand carrying frame (20) to reverse. The sand carrying frame (20), the cover mechanism (30) and the matching plate (40) constitute a box body for loading the sand mold and sand particles. The 3D printing sand mold pouring system further comprises two symmetrical reversing mechanisms (60), the support frame comprises two support members (10) parallel to each other, and the upper ends of the two support members (10) are each provided with a first rack (11) extending along the length direction thereof. The reversing mechanism (60) comprises a sliding member (61) slidably arranged on the support member (10) and capable of sliding along the length direction of the support member (10) and having a third hole (611) formed therein and capable of allowing a sprue cup and a riser cup protruding from a sand mold to pass therethrough, and a rotating shaft (62) connected at one end to the outer wall of the sand carrying frame (20) and connected at the other end to a first gear (63) after penetrating through the third hole (611) of the same side sliding member (61). The first gear (63) can be suspended or engaged with the first rack (11) of the same side, the rotating shaft (62) is rotationally fitted with the third hole (611), and the driving device (50) is used for driving the sliding member (61) to move along the length direction of the support member (10). The opposite sides of the two support members (10) are each provided with a second rack (12) extending along the length direction thereof, the sliding member (61) is rotationally sleeved with a second gear (612), the second gear (612) is engaged with the second rack (12), and the driving device (50) is used for driving the second gear (612) to rotate. The reversing mechanism (60) further comprises a connecting block (64) connected at both ends to the two sliding members (61), the sliding member (61) is further rotationally sleeved with a third gear (613), the third gear (613) and the second gear (612) are coaxially fixedly connected, and the diameter of the second gear (612) is smaller than that of the third gear (613). The driving device (50) comprises a driving member (51) slidably arranged on the connecting block (64) and provided at both sides with a third rack, and an electric push rod (52) having an output end connected to the driving member (51). The third rack is engaged with the third gear (613) of the same side. The upper end of the sand carrying frame (20) is sleeved with a guide ring (21), and the cover mechanism (30) comprises a cover frame (31) slidably sleeved outside the guide ring (21) and provided at the side wall thereof with a guide opening (311) and at the inner wall thereof with a limiting ring (312) capable of abutting against the guide ring (21). ​ ​ 2. A gating system for a 3D printed sand mould according to claim 1, characterized in that ​ 3. A gating system for a 3D printed sand mould according to claim 2, wherein ​ ​ ​ ​ ​ 4. A gating system for a 3D printed sand mould according to claim 3, wherein ​ ​ ​ An outer cover plate (32) is slidably arranged on the port of the cover frame (31) and is provided with a first locking hole (321); An inner partition plate (33) is provided with a second locking hole (331) at one end and is slidably arranged in the cover frame (31) through the guide port (311) and is parallel to the outer cover plate (32), and is provided with a plurality of blanking notches (332); A locking plate (34) is slidably arranged in the first locking hole (321) and the second locking hole (331); The four corners of the locking plate (34) are provided with limiting blocks (341), and the four limiting blocks (341) are abutted with the outer cover plate (32); when the sand carrying frame (20) is turned over, the locking plate (34) is abutted with the driving member (51).

5. A gating system for a 3D printed sand mould according to claim 4, characterized in that One side of the sliding member (61) facing the cover frame (31) is provided with a pressing groove (614), the two side walls of the pressing groove (614) are projected as two mutually parallel involutes, one side of the cover frame (31) facing the sliding member (61) is connected with a pressing rod (313), one end of the pressing rod (313) away from the cover frame (31) is inserted into the pressing groove (614), and the pressing rod (313) is gap-fitted with the pressing groove (614).

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