Sand laying device and sand laying method

Abstract

The application discloses a sand laying device and a sand laying method. The sand laying device comprises a sand laying hopper, a sand feeding mechanism and a driving mechanism. The bottom of the sand laying hopper is provided with a horizontal strip-shaped sand outlet. The sand feeding mechanism comprises two spiral conveying shafts arranged in the sand laying hopper. The two spiral conveying shafts are horizontally extended and arranged in an upper-lower interval. The end of the spiral conveying shaft is referred to as a first end. The sand laying hopper and each first end are connected with a rotary connecting seat, so that the first end is rotatably arranged in the sand laying hopper. The driving mechanism is used for driving the two spiral conveying shafts to rotate and making the conveying directions of the two spiral conveying shafts opposite. When in use, the driving mechanism is started to make the two spiral conveying shafts operate simultaneously. When the sand in the left end of the sand laying hopper is accumulated too much, the accumulated sand in the left end of the sand laying hopper is gradually reduced in a dynamic process, so that the problem that the sand is accumulated too much in a certain place is prevented, and the sand laying is uniform. The same is true for the case that the sand in the right end of the sand laying hopper is accumulated too much.

Description

Technical Field

[0001] This invention relates to the field of 3D printing technology, and in particular to a sand-laying device and sand-laying method. Background Technology

[0002] Sand mold 3D printers require a sand-laying device to lay the molding sand. This device typically includes a strip-shaped sand-laying hopper equipped with a screw conveyor to transport the molding sand to various parts of the hopper. However, in practice, some shortcomings have been found in this device. For example, if the screw conveyor runs for too long / too short a time, excessive sand accumulation or even overflow can occur at the end / beginning of the screw conveyor in the sand-laying hopper, hindering even sand spreading. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a sand-laying device and a sand-laying method.

[0004] A sand-laying apparatus according to a first aspect embodiment of the present invention includes:

[0005] The sand-spreading hopper has a horizontally shaped sand outlet at its bottom;

[0006] The sand feeding mechanism includes two spiral conveying shafts disposed inside the sand spreading hopper. Both spiral conveying shafts extend laterally and are spaced vertically apart. The end of each spiral conveying shaft is referred to as a first end. A rotating connecting seat is connected between the sand spreading hopper and each first end, so that the first end is rotatably disposed in the sand spreading hopper.

[0007] A drive mechanism is used to drive the two spiral conveyor shafts to rotate, so that the conveying directions of the two spiral conveyor shafts are opposite.

[0008] According to the sand-spreading device of the first aspect of the present invention, it has at least the following technical effects: by setting two spiral conveying shafts that are spaced apart vertically and have opposite conveying directions in the sand-spreading hopper, the drive mechanism is activated during use to make the two spiral conveying shafts run simultaneously. When there is too much molding sand accumulated at the left end of the sand-spreading hopper, the spiral conveying shaft used to convey molding sand to the left has greater resistance when conveying molding sand, and the amount of molding sand conveyed to the left is less. On the other hand, the spiral conveying shaft used to convey molding sand to the right has less resistance when conveying molding sand, and the amount of molding sand conveyed to the right is more. This makes the excessive amount of molding sand accumulated at the left end of the sand-spreading hopper gradually decrease during the dynamic process, preventing the problem of excessive accumulation of molding sand in a certain place, which is conducive to uniform sand spreading. The same applies when there is excessive accumulation of molding sand at the right end of the sand-spreading hopper.

[0009] According to some embodiments of the present invention, the side wall of the sand-spreading hopper is provided with a first through hole corresponding to each of the first ends, and the first end passes through the first through hole; the rotating connecting seat is provided with a sealing part, a rotating part and a connecting part connected between the sealing part and the rotating part, the sealing part is fixedly connected to the edge of the first through hole, the rotating part is spaced apart on the side of the sealing part away from the sand-spreading hopper, and the bottom of the connecting part is provided with a sand leakage hole; the sealing part is rotatably sealed to the first end, and the rotating part is rotatably connected to the first end.

[0010] According to some embodiments of the present invention, a sealing ring is provided between the sealing part and the first end, and a bearing is connected between the rotating part and the first end.

[0011] According to some embodiments of the present invention, the sealing part is provided with a cover ring on the side facing the sand-laying hopper, the cover ring being sleeved on the outside of the first end and covering the sealing ring.

[0012] According to some embodiments of the present invention, the sealing portion is provided with an inner raised edge, and the sealing ring abuts between the inner raised edge and the cover ring.

[0013] According to some embodiments of the present invention, all of the said rotating connecting seats are collectively referred to as connecting assemblies, and the drive mechanism is located on the side of the connecting assembly opposite to the sand-laying hopper.

[0014] According to some embodiments of the present invention, the driving mechanism includes a rotary driver and a linkage assembly, wherein the rotary driver is used to drive one of the spiral conveying shafts, and the two spiral conveying shafts are linked together through the linkage assembly.

[0015] According to some embodiments of the present invention, the system further includes a base frame and a sand-spreading conveyor belt, wherein both the sand-spreading hopper and the sand-spreading conveyor belt are connected to the base frame, and the sand-spreading hopper is disposed above the sand-spreading conveyor belt.

[0016] According to some embodiments of the present invention, the sand-laying hopper is provided with a first region and a second region located below the first region, both of the spiral conveying shafts are located in the second region, and the volume of the first region is greater than the volume of a layer of molding sand laid by the sand-laying device.

[0017] According to a second aspect embodiment of the present invention, a sand-laying method is used to lay molding sand using the above-described sand-laying device. The sand-laying method includes the following steps:

[0018] The control drive mechanism is activated, causing the two screw conveyor shafts to run;

[0019] The control base moves forward, and the control sand spreading conveyor belt starts, so that the molding sand in the sand spreading hopper is spread into the printing area by the sand spreading conveyor belt;

[0020] The control frame moves backward to reset, completing the laying of one layer of molding sand;

[0021] Add molding sand to the sand-spreading hopper to fill the first area.

[0022] According to the second aspect of the present invention, the sand spreading method has at least the following technical effects: by using the above-mentioned sand spreading device, the height of molding sand in various parts of the sand spreading hopper can be more uniform, which is beneficial to uniform sand spreading.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0025] Figure 1 This is a three-dimensional structural schematic diagram of the sand-laying device according to an embodiment of the present invention;

[0026] Figure 2 yes Figure 1 A three-dimensional structural diagram of the sand-spreading hopper in the middle;

[0027] Figure 3 yes Figure 2 Right sectional view;

[0028] Figure 4 yes Figure 2 A partial sectional view of the rear view;

[0029] In the attached image:

[0030] 100-Sand spreading hopper; 101-First zone; 102-Second zone; 103-Sand outlet; 110-Screw conveyor shaft; 111-First end; 120-Rotating connecting seat; 121-Sealing part; 122-Connecting part; 123-Rotating part; 124-Sealing ring; 125-Sand leakage hole; 126-Bearing; 130-Gear; 140-Motor; 150-Cover ring; 200-Base frame; 300-Sand spreading conveyor belt. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0032] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the invention and for simplifying the description, and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc., are understood to exclude the stated number, while "above," "below," "within," etc., are understood to include the stated number. If "first" or "second" is used, it is only for the purpose of distinguishing technical features and should not be construed as indicating relative importance or implicitly indicating the number of indicated technical features or the order of the indicated technical features.

[0033] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0034] The following is for reference. Figures 1 to 4 This invention describes a sand-laying device and a sand-laying method according to embodiments of the present invention.

[0035] The sand-laying device according to the first aspect of the present invention, referring to Figure 2 It includes a sand-spreading hopper 100, a sand-feeding mechanism, and a drive mechanism.

[0036] The sand-spreading hopper 100 is a horizontally extending trough shape. The top of the sand-spreading hopper 100 is open, and the bottom of the sand-spreading hopper 100 is provided with a horizontally shaped sand outlet 103. The bottom of the cross-section of the sand-spreading hopper 100 is inverted conical, and the sand outlet 103 is located at the bottom of the inverted conical shape; in this way, the molding sand in the sand-spreading hopper 100 can continuously fall from the sand outlet 103.

[0037] The sand feeding mechanism includes two spiral conveying shafts 110 disposed inside the sand spreading hopper 100. Each spiral conveying shaft 110 includes a central shaft and spiral blades fixedly disposed on the outer periphery of the central shaft, so that when the spiral conveying shaft 110 rotates, its spiral blades can convey molding sand along its axial direction.

[0038] Both spiral conveyor shafts 110 extend laterally and are spaced vertically apart. There is a certain height gap between the top opening of the sand-laying hopper 100 and the top of the upper spiral conveyor shaft 110, so that the molding sand contained in the sand-laying hopper 100 can completely cover the two spiral conveyor shafts 110. The end of the spiral conveyor shaft 110 is called the first end 111. There are a total of four first ends 111 for the two spiral conveyor shafts 110. A rotating connecting seat 120 is connected between the sand-laying hopper 100 and each first end 111. Therefore, there are also four rotating connecting seats 120, so that the four first ends 111 are rotatably set in the sand-laying hopper 100.

[0039] The drive mechanism is used to drive the two screw conveyor shafts 110 to rotate, so that the conveying directions of the two screw conveyor shafts 110 are opposite;

[0040] The two spiral conveying shafts 110 can be configured to have opposite rotation directions and the same rotation direction, or they can be configured to have the same rotation direction and opposite rotation directions, both of which can achieve opposite conveying directions of the two spiral conveying shafts 110.

[0041] This invention provides two vertically spaced spiral conveyor shafts 110 in opposite directions within a sand-spreading hopper 100. When in use, the drive mechanism is activated, causing both spiral conveyor shafts 110 to operate simultaneously. When excessive molding sand accumulates at the left end of the sand-spreading hopper 100, the spiral conveyor shaft 110 used for conveying molding sand to the left experiences greater resistance, resulting in a smaller amount of molding sand conveyed to the left. Conversely, the spiral conveyor shaft 110 used for conveying molding sand to the right experiences less resistance, resulting in a larger amount of molding sand conveyed to the right. This allows the excessive molding sand accumulation at the left end of the sand-spreading hopper 100 to gradually decrease during dynamic operation, preventing excessive accumulation of molding sand in a single location and promoting uniform sand spreading. The same applies when excessive molding sand accumulates at the right end of the sand-spreading hopper 100.

[0042] Meanwhile, since the two spiral conveyor shafts 110 are arranged vertically and vertically, the problem of the molding sand at the corner of the sand spreading hopper 100 being pushed by only one spiral conveyor shaft 110 when the two spiral conveyor shafts 110 are arranged front and back is avoided, which would cause the molding sand to accumulate and overflow.

[0043] In some embodiments of the present invention, reference is made to... Figure 4 Each side wall of the sand-spreading hopper 100 is provided with a first through hole corresponding to each first end 111. That is, the left wall of the sand-spreading hopper 100 is provided with a first through hole, and the right wall of the sand-spreading hopper 100 is also provided with two first through holes. The two first through holes on the left wall of the sand-spreading hopper 100 are arranged vertically at intervals, and the two first through holes on the right wall of the sand-spreading hopper 100 are arranged vertically at intervals.

[0044] The rotating connecting seat 120 is provided with a sealing part 121, a rotating part 123, and a connecting part 122 connecting the sealing part 121 and the rotating part 123. The sealing part 121, the connecting part 122, and the rotating part 123 are all annular and are all sleeved on the outside of the first end 111. The sealing part 121 is fixedly connected to the edge of the first through hole and is rotatably sealed to the first end 111. The sealing part 121 can be installed on the edge of the first through hole by means of bolt connection. The rotating parts 123 are spaced apart from the sealing part 121 and away from the sand spreading hopper. On one side of 100, the rotating part 123 is rotatably connected to the first end 111. Taking the connecting seat set on the left wall of the sand-spreading hopper 100 as an example, the sealing part 121, the connecting part 122, and the rotating part 123 are connected sequentially from right to left. The bottom of the connecting part 122 is provided with a sand leakage hole 125. Of course, the number of sand leakage holes 125 provided in each connecting part 122 can also be multiple. Multiple sand leakage holes 125 are arranged at intervals along the circumference of the connecting part 122. The sealing part 121, the connecting part 122, and the rotating part 123 can be integrally formed components.

[0045] By providing the rotating part 123, the rotating connecting seat 120 can support the screw conveyor shaft 110, allowing the screw conveyor shaft 110 to rotate smoothly. By providing the sealing part 121, during operation, the sealing part 121 can block the molding sand so that the molding sand in the sand spreading hopper 100 will not leak from the first through hole. By providing the connecting part 122 and the sand leakage hole 125, even if a small amount of molding sand leaks through the sealing part 121 and outside the sand spreading hopper 100, this leaked molding sand can fall from the first through hole to the outside of the rotating connecting seat 120, avoiding the problem that this leaked molding sand will move to the rotating part 123 and cause adverse effects on the rotational connection between the screw conveyor shaft 110 and the sand spreading hopper 100.

[0046] In some embodiments of the present invention, a sealing ring 124 is sleeved between the sealing part 121 and the first end 111. The sealing ring 124 is a rubber or other elastic material component, so that the sealing effect between the sealing part 121 and the first end 111 is better. A bearing 126 is connected between the rotating part 123 and the first end 111, so that the rotating part 123 can stably support the first end 111 and the rotation between the rotating part 123 and the first end 111 is smooth.

[0047] In some embodiments of the present invention, a cover ring 150 is provided on the side of the sealing part 121 facing the sand spreading hopper 100. The cover ring 150 is sleeved on the outside of the first end 111 and covers the sealing ring 124. The cover ring 150 can be installed on the sealing part 121 by bolt connection, and the outer diameter of the cover ring 150 is larger than the outer diameter of the sealing ring 124. It is understood that when the screw conveyor shaft 110 conveys the molding sand, it will convey the molding sand axially to collide with the left and right walls of the sand spreading hopper 100; in this embodiment, by providing the cover ring 150, the cover ring 150 can prevent the molding sand from axially colliding with the sealing ring 124, thereby reducing the wear of the sealing ring 124.

[0048] In some embodiments of the present invention, the sealing portion 121 is provided with an inner protruding edge, and the sealing ring 124 abuts between the inner protruding edge and the cover ring 150. The axial dimension of the sealing portion 121 is larger than the axial dimension of the sealing ring 124. The inner protruding edge abuts against the side of the sealing ring 124 away from the sand-spreading hopper 100. The cover ring 150 is provided with a protrusion, which is inserted into the sealing portion 121 and abuts against the side of the sealing ring 124 facing the sand-spreading hopper 100. This can fix the lateral position of the sealing ring 124, eliminate unnecessary relative movement, and reduce wear.

[0049] In some embodiments of the invention, all rotating connecting seats 120 are collectively referred to as connecting assemblies, and the drive mechanism is located on the side of the connecting assembly opposite to the sand-laying hopper 100. This prevents the molding sand leaking from the sealing part 121 from moving to the drive mechanism and thus avoiding damage to it.

[0050] In some embodiments of the present invention, the driving mechanism includes a rotary driver and a linkage assembly. The rotary driver may be an electric motor 140. The rotary driver drives one of the screw conveyor shafts 110. The rotary driver has a main body and a drive shaft. The main body is fixedly mounted on one of the rotating connecting seats 120. The drive shaft is connected to the right end of the lower screw conveyor shaft 110 via a coupling. The two screw conveyor shafts 110 are linked together via the linkage assembly. In this way, only one rotary driver is needed to drive both screw conveyor shafts 110, resulting in a simple structure and reduced equipment manufacturing and maintenance costs.

[0051] In some embodiments of the present invention, reference is made to... Figure 1 The sand-laying device also includes a base frame 200 and a sand-laying conveyor belt 300. Both the sand-laying hopper 100 and the sand-laying conveyor belt 300 are connected to the base frame 200, with the sand-laying hopper 100 positioned above the sand-laying conveyor belt 300. Controlling the movement of the base frame 200 and starting the sand-laying conveyor belt 300 allows the molding sand in the sand-laying hopper 100 to be laid onto the printing area via the sand-laying conveyor belt 300. Adjusting the running speed of the sand-laying conveyor belt 300 adjusts the amount of sand laid. The sand-laying conveyor belt 300 simultaneously functions as a sand-laying switch and adjusts the amount of sand laid. It has a simple structure and is easy to use.

[0052] In some embodiments of the present invention, the horizontal projections of the sand outlet 103 and all sand leakage holes 125 are located within the sand spreading conveyor belt 300. This ensures that the molding sand discharged from the sand leakage holes 125 is also received by the sand spreading conveyor belt 300, preventing this portion of molding sand from falling onto other electrical components and causing malfunctions.

[0053] In some embodiments of the present invention, the linkage assembly includes two gears 130, which mesh with each other and are respectively disposed on two spiral conveying shafts 110. The two gears 130 are correspondingly disposed on the left ends of the two spiral conveying shafts 110, achieving the purpose of linkage between the two spiral conveying shafts 110. Thus, the drive mechanism is connected to the sand-spreading hopper 100, eliminating the need for an additional mounting bracket for installation and fixation of the drive mechanism. The structure is simple and easy to move along with the sand-spreading hopper 100.

[0054] In some embodiments of the present invention, the rotary drive and the linkage assembly are respectively located at both ends of the sand-laying hopper 100. This prevents the rotary drive and the linkage assembly from interfering with each other, and provides ample space on either side of both for easy maintenance. Two gears 130 are located at the ends of the sand-laying hopper 100, facilitating replacement to change the transmission ratio and adapt to different molding sand formulations.

[0055] In some embodiments of the present invention, reference is made to... Figure 3 The sand-laying hopper 100 is provided with a first region 101 and a second region 102 located below the first region 101. Both spiral conveyor shafts 110 are located in the second region 102. The volume of the first region 101 is larger than the volume of a layer of molding sand laid by the sand-laying device. By setting the first region 101, sufficient space is left to accommodate the molding sand. In this way, during the printing process, the molding sand in the sand-laying hopper 100 can always completely cover the two spiral conveyor shafts 110, so that the flow rate of the molding sand conveyed by the spiral conveyor shaft 110, whether located on the lower side or the upper side, will not change. Therefore, the height of the molding sand in all parts of the sand-laying hopper 100 can maintain a dynamic balance and tend to be consistent. The two spiral conveyor shafts 110 can run continuously to keep the molding sand loose.

[0056] The sand-laying method according to a second aspect of the present invention uses the above-described sand-laying device to lay molding sand, and the sand-laying method includes the following steps:

[0057] Step S100: Control the drive mechanism to start, causing the two screw conveyor shafts 110 to run;

[0058] Step S200: Control the base frame 200 to move forward and control the sand spreading conveyor belt 300 to start, so that the molding sand in the sand spreading hopper 100 is spread on the printing area by the sand spreading conveyor belt 300;

[0059] Step S300: Control the base frame 200 to move backward and reset, completing the laying of one layer of molding sand;

[0060] Step S400: Add molding sand to the sand-spreading hopper 100 to fill the first area 101 with molding sand;

[0061] Step S500: Repeat steps S200, S300 and S400 above to achieve the layer-by-layer laying of molding sand.

[0062] By using the sand-spreading device described above, the height of molding sand in various parts of the sand-spreading hopper 100 can be relatively uniform, which is conducive to uniform sand spreading.

[0063] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A sand-laying device, characterized in that, include: The sand-spreading hopper has a horizontally shaped sand outlet at its bottom; The sand feeding mechanism includes two spiral conveying shafts disposed inside the sand spreading hopper. Both spiral conveying shafts extend laterally and are spaced vertically apart. The end of each spiral conveying shaft is referred to as a first end. A rotating connecting seat is connected between the sand spreading hopper and each first end, so that the first end is rotatably disposed in the sand spreading hopper. A drive mechanism is used to drive the two spiral conveying shafts to rotate, so that the conveying directions of the two spiral conveying shafts are opposite; The side wall of the sand-spreading hopper is provided with a first through hole corresponding to each of the first ends, and the first end passes through the first through hole; the rotating connecting seat is provided with a sealing part, a rotating part and a connecting part connecting the sealing part and the rotating part, the sealing part is fixedly connected to the edge of the first through hole, the rotating part is spaced apart on the side of the sealing part away from the sand-spreading hopper, and the bottom of the connecting part is provided with a sand leakage hole; the sealing part is rotatably sealed to the first end, and the rotating part is rotatably connected to the first end.

2. The sand-laying device according to claim 1, characterized in that: A sealing ring is fitted between the sealing part and the first end, and a bearing is connected between the rotating part and the first end.

3. The sand-laying device according to claim 2, characterized in that: The sealing part is provided with a cover ring on the side facing the sand-spreading hopper. The cover ring is sleeved on the outside of the first end and covers the sealing ring.

4. The sand-laying device according to claim 3, characterized in that: The sealing part has an inner raised edge, and the sealing ring abuts between the inner raised edge and the cover ring.

5. The sand-laying device according to claim 1, characterized in that: All of the aforementioned rotating connecting seats are collectively referred to as the connecting assembly, and the drive mechanism is located on the side of the connecting assembly opposite to the sand-laying hopper.

6. The sand-laying device according to claim 1, characterized in that: The drive mechanism includes a rotary driver and a linkage assembly. The rotary driver is used to drive one of the spiral conveyor shafts, and the two spiral conveyor shafts are linked together through the linkage assembly.

7. The sand-laying device according to claim 1, characterized in that: It also includes a base frame and a sand-spreading conveyor belt, wherein both the sand-spreading hopper and the sand-spreading conveyor belt are connected to the base frame, and the sand-spreading hopper is located above the sand-spreading conveyor belt.

8. The sand-laying device according to claim 7, characterized in that: The sand-laying hopper has a first region and a second region located below the first region. Both of the spiral conveying shafts are located in the second region. The volume of the first region is greater than the volume of a layer of molding sand laid by the sand-laying device.

9. A method for spreading sand, characterized in that: The method of laying molding sand using the sand-laying device as described in claim 8 includes the following steps: The control drive mechanism is activated, causing the two screw conveyor shafts to run; The control base moves forward, and the control sand spreading conveyor belt starts, so that the molding sand in the sand spreading hopper is spread into the printing area by the sand spreading conveyor belt; The control frame moves backward to reset, completing the laying of one layer of molding sand; Add molding sand to the sand-spreading hopper to fill the first area.

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