Sealing element for 3D printing powder spreading piston and powder spreading piston

Abstract

The utility model relates to the technical field of 3D printing, in particular to a sealing element for a 3D printing powder spreading piston and the powder spreading piston, which comprise a deformation part with a square section outline, elasticity and hollow interior, and an inflation port with one end connected with the deformation part and the other end connected with an inflation and deflation system, the central axis of the inflation inlet is parallel to the central line of the sealing piece. The reinforcing part covers the outer side of the deformation part, the section contour of the reinforcing part is the same as that of the deformation part, and the reinforcing part is provided with a positioning sleeve used for allowing the inflation inlet to penetrate through; through the arrangement, the sealing element is high in sealing performance, uniform in stress and not prone to damage, the service life of the sealing element is prolonged, and the printing precision is ensured.

Description

Technical Field

[0001] This utility model relates to a sealing component and a powder-spreading piston for 3D printing, belonging to the field of 3D printing technology. Background Technology

[0002] Metal powder SLM 3D printing technology has become a hot research topic in recent years. During operation, the powder spreading piston needs to be sealed to prevent metal powder leakage and to ensure the stability of the inert environment during printing. If metal powder leakage occurs due to poor sealing, it will not only cause waste and affect printing accuracy, but may also pose safety hazards to equipment and operators.

[0003] Currently, piston sealing mostly employs the method of springs pressing against felt or packing to seal the piston. The drawbacks of this method are twofold: firstly, the airtightness of felt and packing is very poor; secondly, it is difficult to ensure that multiple springs are perfectly aligned, leading to uneven force distribution around the piston, causing it to deviate from the center and thus affecting piston centering and printing accuracy. Another method uses rubber sealing rings to seal the piston, but these are found to wear out quickly during use, resulting in a short service life and high production and operating costs. Therefore, researching a new type of sealing component is of great practical significance. Utility Model Content

[0004] This invention addresses the shortcomings of existing technologies by providing a sealing component and a powder-spreading piston for 3D printing.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A sealing component for a 3D printing powder-laying piston includes: a deformable part, the deformable part having a square cross-sectional profile, being elastic and hollow inside, and also including an air inlet, one end of the air inlet being connected to the deformable part, and the other end being connected to an air inflation / deflation system, the central axis of the air inlet being parallel to the center line of the sealing component; a reinforcing part, the reinforcing part covering the outside of the deformable part and having the same cross-sectional profile as the deformable part, and a positioning sleeve for the air inlet to pass through is provided on the reinforcing part.

[0006] Furthermore, the outer surface of the deformable part away from the center line of the seal is provided with a plurality of reinforcing ridges, the reinforcing ridges extending in a direction perpendicular to the center line of the seal.

[0007] Furthermore, the cross-sectional profile of the reinforcing ridge is arc-shaped, and a reinforcing bevel is provided at the contact point between the reinforcing ridge and the deformed part.

[0008] Furthermore, the outer surface is surrounded by four reinforcing ridges, which are divided into the first reinforcing ridge, the second reinforcing ridge, the third reinforcing ridge, and the fourth reinforcing ridge from top to bottom. The relationship between the vertical distance L1 between the center lines of adjacent reinforcing ridges, the vertical distance L2 from the center line of the first reinforcing ridge to the plane of the upper surface, the vertical distance L3 from the center line of the fourth reinforcing ridge to the plane of the lower surface, and the height H1 of the outer surface satisfies L1:L2:L3:H1=(1.4-1.8):1:1:(7.5-8.5).

[0009] Furthermore, the first and fourth reinforcing edges are of the same size, the second and third reinforcing edges are of the same size, and the vertical height H2 from the vertex of the first or fourth reinforcing edge to the outer surface is greater than the vertical height H3 from the vertex of the second or third reinforcing edge to the outer surface.

[0010] Furthermore, the vertical height H2 from the vertex of the first or fourth reinforcing edge to the outer surface is 1.1-1.35 times the vertical height H3 from the vertex of the second or third reinforcing edge to the outer surface.

[0011] Furthermore, both the upper and lower sides of the deformable part are integrally formed with protrusions facing the center of the deformable part, and the cross-sectional profile of the protrusions is arc-shaped.

[0012] Furthermore, a transition slope is provided at the connection between the outer side and the upper side and the lower side, and the cross-sectional profile of the transition slope is a line segment.

[0013] Furthermore, a flexible part is also fitted inside the deformable part, the cross-sectional profile of the flexible part is the same as the cross-sectional profile of the inner side of the deformable part, and a through hole is provided in the flexible part corresponding to the position of the air inlet.

[0014] This utility model also provides a powder spreading piston, which is movably disposed in a 3D printing molding cylinder. The powder spreading piston is provided with a sealing ring groove, and the sealing element mentioned above is installed in the sealing ring groove.

[0015] The beneficial effects of this utility model are:

[0016] Through the above settings, firstly, while solving the problem of poor sealing caused by uneven force when sealing with springs, it also solves the problems of poor wear resistance and short service life of previous inflatable seals. The seal of this application has strong sealing performance, uniform force distribution, and is not easily damaged, thus extending the service life of the seal and ensuring printing accuracy. Secondly, by setting the central axis of the inflation port to be parallel to the center line of the seal, and the inflation port being located on the upper or lower side of the seal, it saves space and avoids the problem of the inflation port being pulled by the seal during up-and-down reciprocating movement due to the inflation port being located on the inner side or misaligned, which would lead to damage and leakage, thus affecting the sealing performance and service life. Finally, by setting a positioning sleeve, it further prevents the inflation port from being pulled and swayed, further prevents damage to the connection between the inflation port and the deformation part, further ensures the sealing performance, and extends the service life. Attached Figure Description

[0017] Figure 1 This is a three-dimensional cross-sectional view of the sealing element described in Embodiment 1 of this utility model;

[0018] Figure 2 This is a schematic diagram of the cross-sectional structure of the sealing element described in Embodiment 1 of this utility model;

[0019] Figure 3 This is a schematic diagram of the deformable part structure described in Embodiment 1 of this utility model;

[0020] Figure 4 This is a schematic diagram of the outer surface structure of Embodiment 1 of this utility model.

[0021] Reference numerals: 01, Seal; 1, Deformation part; 11, Inflation port; 12, Inner side; 13, Outer side; 14, Reinforcing ridge; 141, First reinforcing ridge; 142, Second reinforcing ridge; 143, Third reinforcing ridge; 144, Fourth reinforcing ridge; 15, Reinforcing slope; 16, Upper side; 17, Lower side; 18, Protrusion; 19, Transition slope; 2, Reinforcing part; 21, Positioning sleeve; 3, Flexible part. Detailed Implementation

[0022] The specific embodiments of this utility model are described in detail below. This utility model can be implemented in many ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein.

[0023] 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 is for describing particular embodiments only and is not intended to limit the scope of this invention.

[0024] In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply 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 this utility model.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0026] Example 1

[0027] like Figure 1 As shown, this utility model provides a sealing component for a 3D printing powder-laying piston, comprising: a deformable part 1, the deformable part 1 having a square cross-sectional profile, being elastic and hollow inside, and also including an inflation port 11, one end of the inflation port 11 being connected to the deformable part 1, and the other end being connected to an inflation / deflation system, the central axis of the inflation port 11 being parallel to the center line C of the sealing component; and a reinforcing part 2, the reinforcing part 2 covering the outside of the deformable part 1 and having the same cross-sectional profile as the deformable part 1, the reinforcing part 2 being provided with a positioning sleeve 21 for the inflation port 11 to pass through.

[0028] It should be noted that the sealing element 01 in this embodiment of the present invention is square, and the expansion and contraction of the deformable part 1 is achieved by inflation and deflation. The inflation and deflation system is a conventional technical means in the field, so it is not shown in the drawings. "Covering" refers to the outer surface of the deformable part 1 and the inner surface of the reinforcing part 2 being in close contact with each other. The deformable part 1 is made of rubber or silicone, and the reinforcing part 2 is made of a wear-resistant material with a certain elastic deformation capacity, such as aramid braid. Although the reinforcing part 2 can expand and contract synchronously with the deformable part 1, due to the limitations of different materials, the deformation capacity of the reinforcing part 2 is lower than that of the deformable part 1. Therefore, the reinforcing part 2 also has the function of preventing the deformable part 1 from being damaged by excessive expansion under high pressure.

[0029] Through the above settings, firstly, while solving the problem of poor sealing caused by uneven force when sealing with spring pressure, it also solves the problems of poor wear resistance and short service life of previous inflatable seals. The seal of this application has strong sealing performance, uniform force distribution, and is not easily damaged, thus extending the service life of the seal and ensuring printing accuracy. Secondly, by setting the central axis of the inflation port 11 to be parallel to the center line C of the seal, and the inflation port 11 located on the upper or lower side of the seal 01, it not only saves space but also avoids the problem of the inflation port 11 being pulled by the seal 01 during the up-and-down reciprocating movement due to its location on the inner side 12 or its skewed setting, which would lead to damage and leakage, thus affecting the sealing performance and service life. Finally, by setting the positioning sleeve 21, it further prevents the inflation port 11 from being pulled and swayed, further prevents damage to the connection between the inflation port 11 and the deformation part 1, further ensures the sealing performance and extends the service life.

[0030] It should be noted that the above described in this application is based on the appendix. Figure 1 The upper end of the center line C of the central sealing component is towards the lower side, which is based on the attached... Figure 1 The inner surface 12 is located near the lower end of the center line C of the central sealing component. Figure 1 On one side of the centerline C of the central seal, the outer surface 13 is away from the attached... Figure 1 One side of the center line C of the central sealing component.

[0031] Specifically, such as Figure 1-4 As shown, the outer surface 13 of the deformable part 1, away from the center line C of the seal, is surrounded by a plurality of reinforcing ridges 14, the reinforcing ridges 14 extending perpendicularly to the center line C of the seal. The reinforcing ridges 14 and the deformable part 1 are integrally formed. The cross-sectional profile of the reinforcing part 2 is the same as that of the deformable part 1 after the reinforcing ridges 14 are provided. By providing the reinforcing ridges 14, wear on the outer surface 13 can be reduced, and the maximum contact stress between the seal 01 and the inner wall of the forming cylinder can be increased, further improving the sealing performance and applicability. Preferably, the cross-sectional profile of the reinforcing ridges 14 is arc-shaped, and a reinforcing bevel 15 is provided at the contact points between the reinforcing ridges 14 and the deformable part 1. By setting the cross-sectional profile of the reinforcing rib 14 to be arc-shaped, under the condition of reciprocating sealing of the sealing element 01, the reinforcing rib 14 will not get stuck when the up and down direction is changed, avoiding bending or breakage of the reinforcing rib 14 due to local stress concentration when the direction is changed. Furthermore, by setting the reinforcing inclined surface 15, the structural strength of the reinforcing rib 14 is further improved, further ensuring the sealing performance.

[0032] Specifically, such as Figure 2-4As shown, the outer surface 13 is surrounded by four reinforcing ridges 14, which are divided into the first reinforcing ridge 141, the second reinforcing ridge 142, the third reinforcing ridge 143, and the fourth reinforcing ridge 144 from top to bottom. The vertical distance L1 between the center lines of adjacent reinforcing ridges 14, the vertical distance L2 from the center line of the first reinforcing ridge 141 to the plane of the upper surface 16, the vertical distance L3 from the center line of the fourth reinforcing ridge 144 to the plane of the lower surface 17, and the height H1 of the outer surface 13 are related by L1:L2:L3:H1 = (1.4-1.8):1:1:(7.5-8.5). First, by setting four reinforcing ridges 14, the sealing performance of the seal 01 is effectively improved. Compared with setting a single reinforcing ridge 14, the fault tolerance is higher, reducing the probability of affecting printing accuracy due to seal leakage. Second, by limiting the above-mentioned dimensional relationship, a certain distance is maintained between adjacent reinforcing ridges 14. This ensures that the seal 01 has a certain heat dissipation effect, reducing the impact of heat generated during the active sealing process on the sealing performance and service life of the seal 01. It also ensures that the reinforcing part 2 flatly covers the reinforcing ridges 14, avoiding wrinkles in the reinforcing part 2 covering the reinforcing ridges 14 that affect the seal. Furthermore, through the above settings, the first reinforcing ridge 141 and the fourth reinforcing ridge 144 are closer to the plane of the upper side 16 and the plane of the lower side 17, improving the structural strength at the connection between the upper side 16 and the lower side 17 and the outer side 13. This solves the problem that the connection between the upper side 16 and the lower side 17 and the outer side 13 is easily squeezed into the active gap and thus bitten and damaged during the active sealing process, effectively extending the service life.

[0033] Specifically, such as Figure 3-4As shown, the first reinforcing ridge 141 and the fourth reinforcing ridge 144 have the same dimensions, and the second reinforcing ridge 142 and the third reinforcing ridge 143 have the same dimensions. The vertical height H2 from the vertex of the first reinforcing ridge 141 or the fourth reinforcing ridge 144 to the outer surface 13 is greater than the vertical height H3 from the vertex of the second reinforcing ridge 142 or the third reinforcing ridge 143 to the outer surface 13. This design takes into account that during the inflation and expansion of the deformable part 1, the outer surface 13 located at the positions of the second reinforcing ridge 142 and the third reinforcing ridge 143 will preferentially bulge out. If the deformable part 1 only requires a lower internal inflation pressure to meet the sealing requirements under the corresponding process conditions, then the first reinforcing ridge 141 and the fourth reinforcing ridge 144 cannot form an effective seal, resulting in poor sealing performance, lower sealing tolerance, and lower applicability. Through the above design, it can be ensured that all four reinforcing ridges 14 form an effective seal during the active sealing process, ensuring the sealing performance and applicability of the sealing element 01 described in this application. Preferably, the vertical height H2 from the vertex of the first reinforcing ridge 141 or the fourth reinforcing ridge 144 to the outer surface 13 is 1.1-1.35 times the vertical height H3 from the vertex of the second reinforcing ridge 142 or the third reinforcing ridge 143 to the outer surface 13. If H2 is less than 1.1 times H3, the internal pressure of the deformation part 1 is too high in order to make all four reinforcing ridges 14 form an effective seal, which increases the burden on the deformation part 1, the reinforcing part 2 and the inflation / deflation system, affecting the service life. If H2 is greater than 1.35 times H3, a larger inflation pressure is not required for the four reinforcing ridges 14 to abut against the inner wall of the molding cylinder, but the maximum contact stress is insufficient, the pressure range that the seal 01 can adapt to becomes smaller, and the applicability is reduced.

[0034] Specifically, such as Figure 2-4 As shown, both the upper side 16 and lower side 17 of the deformable part 1 are integrally formed with a protrusion 18 facing the center of the deformable part 1, and the cross-sectional profile of the protrusion 18 is arc-shaped. It should be noted that the protrusion 18 and the deformable part 1 are integrally formed. By setting the protrusion 18, the structural strength of the upper side 16 and lower side 17 is strengthened, the expansion tendency of the upper side 16 and lower side 17 is weakened, and the expansion direction of the outer side 13 is ensured to be accurate. In addition, during the pressurization and expansion process, the outer arc of the protrusion 18 is compressed, and the compressed air applies a force to the protrusion 18 toward the inner center of the protrusion 18, thereby further reducing the stress at the connection between the upper side 16 and lower side 17 and the outer side 13, further avoiding the problem of the seal 01 being squeezed into the moving gap and thus being bitten and damaged, and further extending the service life.

[0035] Specifically, a transition slope 19 is provided at the connection between the outer side 13 and the upper side 16 and the lower side 17, and the cross-sectional profile of the transition slope 19 is a line segment. The transition slope 19 can further limit the expansion deformation at the connection between the upper side 16 and the lower side 17 and the outer side 13, and further avoid the problem of the seal 01 being damaged by gaps. Furthermore, a transition slope 19 is also provided at the connection between the inner side 12 and the upper side 16 and the lower side 17.

[0036] Specifically, a flexible part 3 is also fitted inside the deformable part 1. The cross-sectional profile of the flexible part 3 is the same as that of the inner side of the deformable part 1, and a through hole is provided in the flexible part 3 corresponding to the position of the inflation port 11. By providing the flexible part 3, the pressure-bearing capacity of the deformable part 1 is further improved, providing the deformable part 1 with shape recovery force after depressurization, avoiding the problem of the deformable part 1 being unable to return to its initial shape due to prolonged inflation, and helping to further extend its service life.

[0037] Example 2

[0038] This invention provides a powder-spreading piston, which is movably disposed within a 3D printing molding cylinder. The powder-spreading piston has a sealing ring groove, and a sealing element 01, as described in Embodiment 1, is installed in the sealing ring groove. The sealing element 01 provides a seal during the up-and-down movement of the powder-spreading piston.

[0039] 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 exhaustively listed. 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.

[0040] For those skilled in the art, various modifications and improvements can be made without departing from the concept of this utility model, and these modifications and improvements are all within the protection scope of this utility model. The protection scope of this utility model is defined by the appended claims.

Claims

1. A seal for a 3D-printed powder-spreading piston, characterized in that, include: The deformable part has a square cross-sectional profile, is elastic and hollow inside, and also includes an air inlet. One end of the air inlet is connected to the deformable part, and the other end is connected to the inflation / deflation system. The central axis of the air inlet is parallel to the center line of the sealing element. A reinforcing part is provided, which covers the outside of the deformable part and has the same cross-sectional profile as the deformable part. A positioning sleeve for the air inlet to pass through is provided on the reinforcing part.

2. A seal for a 3D printing powder-laying piston according to claim 1, characterized in that, The outer surface of the deformable part away from the center line of the seal is provided with several reinforcing ridges, and the reinforcing ridges extend perpendicularly to the center line of the seal.

3. A seal for a 3D printing powder-laying piston according to claim 2, characterized in that, The cross-sectional profile of the reinforcing rib is arc-shaped, and a reinforcing bevel is provided at the contact point between the reinforcing rib and the deformed part.

4. A seal for a 3D printing powder-laying piston according to claim 3, characterized in that, The outer surface is surrounded by four reinforcing ridges, which are divided into the first reinforcing ridge, the second reinforcing ridge, the third reinforcing ridge, and the fourth reinforcing ridge from top to bottom. The vertical distance L1 between the center lines of adjacent reinforcing ridges, the vertical distance L2 from the center line of the first reinforcing ridge to the plane of the upper surface, the vertical distance L3 from the center line of the fourth reinforcing ridge to the plane of the lower surface, and the height H1 of the outer surface satisfy L1:L2:L3:H1=(1.4-1.8):1:1:(7.5-8.5).

5. A seal for a 3D printing powder-laying piston according to claim 4, characterized in that, The first and fourth reinforcing edges have the same size, the second and third reinforcing edges have the same size, and the vertical height H2 from the vertex of the first or fourth reinforcing edge to the outer side surface is greater than the vertical height H3 from the vertex of the second or third reinforcing edge to the outer side surface.

6. A seal for a 3D printing powder-laying piston according to claim 5, characterized in that, The vertical height H2 from the vertex of the first or fourth reinforcing edge to the outer surface is 1.1 to 1.35 times the vertical height H3 from the vertex of the second or third reinforcing edge to the outer surface.

7. A seal for a 3D printing powder-laying piston according to claim 2, characterized in that, The upper and lower sides of the deformable part are integrally formed with protrusions facing the center of the deformable part, and the cross-sectional profile of the protrusions is arc-shaped.

8. A seal for a 3D printing powder-laying piston according to claim 7, characterized in that, The outer side is provided with a transition slope at the connection between the outer side and the upper side and the lower side, and the cross-sectional profile of the transition slope is a line segment.

9. A seal for a 3D printing powder-laying piston according to claim 1, characterized in that, A flexible part is also fitted inside the deformable part. The cross-sectional profile of the flexible part is the same as that of the inner cross-sectional profile of the deformable part. A through hole is provided in the flexible part corresponding to the position of the air inlet.

10. A powder-spreading piston, characterized in that, The powder-spreading piston is movably disposed inside the 3D printing molding cylinder, and a sealing ring groove is provided on the powder-spreading piston, wherein the sealing element as described in any one of claims 1-9 is installed in the sealing ring groove.

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