Heating tube sealing mechanism, vacuum oven and vacuum parallel seam welder

Abstract

The present application relates to a heating pipe sealing mechanism, a vacuum oven and a vacuum parallel seam welding machine, and belongs to the technical field of oven sealing. The heating pipe sealing mechanism comprises a fixed seat, a first through hole of a connecting shell, and a second through hole; a sealing part is arranged between the heating pipe and the second through hole; a pressing part is used for pressing the sealing part on the fixed seat; the sealing part comprises a first sealing piece and a second sealing piece, the longitudinal section structure of the first sealing piece is V-shaped, the pressing part is provided with an annular protrusion with a V-shaped longitudinal section; the V-shaped angle of the annular protrusion is greater than the V-shaped angle of the first sealing piece; the second sealing piece abuts against the first sealing piece, a wedge-shaped space is formed between the second through hole and the heating pipe, and the shape of the second sealing piece matches the wedge-shaped space. Through the innovative structure of the sealing part and the pressing part, the axial pressing force of the pressing part can be converted into radial extrusion on the sealing part, strong radial holding force and occlusal force are generated between the heating pipe and the fixed seat, and the sealing effect is excellent.

Description

Technical Field

[0001] This invention relates to the field of oven sealing technology, specifically to a heating tube sealing mechanism, a vacuum oven, and a vacuum parallel seam welding machine. Background Technology

[0002] A vacuum oven is a box-type device that heats and dries materials under negative pressure. It is widely used in electronics, chemical engineering, and materials science, especially when used in conjunction with a glove box to achieve sealed material transport and processing. The vacuum oven has an internal heating plate to hold the material, typically using electric heating via heating tubes embedded in the plate for heat conduction. However, the heating tubes must pass through openings in the oven shell, making sealing difficult. Traditional sealing solutions often use organic materials such as rubber or PTFE, but because the heating tubes generate high-temperature radiation during operation (reaching surface temperatures of up to 200°C), these organic seals are prone to aging, hardening, or even melting under prolonged high temperatures, leading to vacuum leaks. These leaks not only affect drying efficiency and product quality but can also allow air or moisture to enter the oven, causing product oxidation and spoilage. Furthermore, frequent leak repairs increase equipment maintenance costs.

[0003] Therefore, there is an urgent need for a sealing mechanism that is resistant to high temperatures, has a long service life, and has excellent sealing performance, in order to improve the overall performance and economy of vacuum ovens. Summary of the Invention

[0004] The purpose of this invention is to provide a heating tube sealing mechanism, a vacuum oven, and a vacuum parallel seam welding machine, which can solve the technical problem of poor sealing between the heating tube and the oven mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] The first aspect of the present invention provides a heating tube sealing mechanism for a vacuum oven. The oven shell has a first through hole. The heating tube sealing mechanism includes a fixing seat, a sealing part, and a pressing part. The fixing seat is connected to the first through hole of the shell and has a second through hole for the heating tube to pass through. The sealing part is sleeved on the heating tube and disposed between the heating tube and the inner wall of the second through hole. The pressing part is sleeved on the heating tube and is used to press the sealing part onto the fixing seat. The sealing part includes a first sealing element and a second sealing element. The longitudinal section of the first sealing element is constructed as a V-shaped structure with a predetermined thickness. The pressing part has an annular protrusion with a V-shaped longitudinal section. The V-angle α of the annular protrusion is greater than the V-angle β of the first sealing element. The second sealing element is sleeved on the heating tube and abuts against the bottom of the first sealing element. A wedge-shaped space is formed between the second through hole and the heating tube. The shape of the second sealing element matches the wedge-shaped space. In this design, when the pressing part is tightened, the inclined surface of the annular protrusion squeezes the first sealing element, forming a seal between the outer wall of the heating tube and the inner wall of the second through hole. By setting the second sealing element, it can bear and disperse part of the axial force from the first sealing element and convert it into its own displacement tendency toward the small end of the wedge-shaped space, thereby generating a radial clamping force on the heating tube and further enhancing the sealing effect. At the same time, through the support of the second sealing element, the deformation amplitude and stress level of the bottom area of ​​the first sealing element can be reduced, ensuring the uniformity and stability of the contact pressure between the second sealing surface of the first sealing element and the fixed seat.

[0007] In a preferred embodiment, the V-shaped structure of the first seal includes a first V-shaped surface and a second V-shaped surface, which together form the inner wall structure and the outer wall structure of the first seal. The inner wall structure fits against the outer wall of the heating tube to form a first sealing surface, and the outer side of the second V-shaped surface engages with the edge of the inlet end of the second through hole to form a second sealing surface.

[0008] In a preferred embodiment, the top of the first V-shaped surface is configured as an arc-shaped transition structure. This arc-shaped transition structure abuts against the annular protrusion of the pressing portion, which helps to uniformly transmit force and reduce local stress concentration.

[0009] In a preferred embodiment, the thickness of the first seal is 1-2 mm. This thickness setting can balance the sealing strength and deformation capacity. If it is too thin, it may result in insufficient sealing pressure and insufficient strength, while if it is too thick, it may require a larger clamping force and have poor elastic deformation capacity.

[0010] In a preferred embodiment, the first seal is made of a high-temperature resistant elastic metal material to ensure that it can maintain its sealing performance and adapt to thermal deformation under high-temperature conditions.

[0011] In a preferred embodiment, the pressing part is locked and fixed to the fixed base by a locking member, and the axial pressing force of the pressing part is adjusted by the locking member.

[0012] In a preferred embodiment, the inner diameter of the inlet end of the second through hole is larger than the inner diameter of the outlet end, forming a variable diameter structure for accommodating the sealing portion.

[0013] A second aspect of the present invention provides a vacuum oven, comprising a working cavity formed by a shell, a heating plate disposed in the working cavity, and a heating tube providing a heat source for the heating plate, wherein the heating tube is mounted on the shell by a heating tube sealing mechanism as described in any of the above embodiments.

[0014] A third aspect of the present invention provides a vacuum parallel seam welding machine, including a vacuum chamber and a vacuum oven, wherein the vacuum oven is fixedly connected to both sides of the vacuum chamber.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] 1) By innovating the structure of the sealing part and the pressing part that cooperates with it, this invention can convert the axial pressing force of the pressing part into radial extrusion on the sealing part, generating a strong radial clamping force and biting force between the heating tube and the through hole of the fixed seat, resulting in excellent sealing effect.

[0017] 2) By setting the cooperation of the first seal and the second seal, multiple seals and stress optimization can be formed. The second seal improves the stress state of the first seal through mechanical support and extends its service life. At the same time, even if the first seal fails slightly under extreme working conditions, the second seal can still maintain an effective seal. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the vacuum oven in an embodiment of the present invention;

[0019] Figure 2 This is a front view of the vacuum oven in an embodiment of the present invention;

[0020] Figure 3 for Figure 2 Sectional view along the AA direction;

[0021] Figure 4 for Figure 3 Enlarged view of part A;

[0022] Figure 5 This is a schematic diagram of the structure of the fixing base in an embodiment of the present invention;

[0023] Figure 6 This is a cross-sectional view of the fixing seat at the second through hole position in an embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of the structure of the first sealing element in an embodiment of the present invention;

[0025] Figure 8 This is a cross-sectional view of the first sealing element in an embodiment of the present invention;

[0026] Figure 9 This is a schematic diagram of the pressing part in an embodiment of the present invention;

[0027] Figure 10 This is a rear view of the pressing part in an embodiment of the present invention;

[0028] Figure 11 for Figure 10 Sectional view in the BB direction.

[0029] The meanings of the labels in the diagram are as follows:

[0030] 1. Housing; 2. Sealing door; 3. Heating plate; 4. Heating tube; 5. Fixing base; 51. Fixing base; 52. Protrusion; 53. Second through hole; 531. Large through hole; 532. Small through hole; 6. Sealing part; 61. First sealing element; 611. First V-shaped surface; 612. Second V-shaped surface; 613. Inner wall structure; 614. Outer wall structure; 62. Second sealing element; 7. Pressing part; 71. Pressing plate; 72. Annular protrusion; 8. Locking element; 9. Gap. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "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 invention 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 invention.

[0033] Example 1

[0034] Figures 1-3A schematic diagram of a vacuum oven is shown. The vacuum oven has a square working chamber enclosed by a shell 1, and each end of the square working chamber has an openable and closable sealing door 2. One sealing door 2 is used to convey the material to be heated into the working chamber, and the other end connects to a glove box for transferring the heated material to the glove box for further processing. Multiple heating plates 3 are provided inside the working chamber to hold and heat the material, and each heating plate 3 contains heating pipes 4 that provide a heat source. The heating pipes 4 pass through the oven shell 1 and the heating plates 3.

[0035] See Figure 3 In this embodiment, the heating tube sealing mechanism for a vacuum oven includes a fixing seat 5, a sealing part 6, and a pressing part 7. The fixing seat 5 is connected to the oven shell 1 and is used to connect the heating tube 4. The sealing part 6 is disposed between the heating tube 4 and the fixing seat 5, playing a crucial sealing role. The pressing part 7 is used to press the sealing part 6 tightly, ensuring the stability and reliability of the seal.

[0036] Specifically, the oven shell 1 has a first through hole, and the fixing seat 5 is installed in the first through hole. The fixing seat 5 also has a second through hole 53. The heating tube 4 passes through the second through hole 53 from the outside of the oven and enters the oven interior, and further extends into the heating plate 3. The sealing part 6 is disposed in the gap between the heating tube 4 and the inner wall of the second through hole 53. The pressing part 7 is sleeved on the heating tube 4 and presses the sealing part 6 onto the fixing seat 5 to enhance the sealing effect.

[0037] For more details, see Figure 5 and Figure 6 The fixing base 5 includes a fixing base 51 and a protrusion 52 integrally connected to the fixing base 51. The outer diameter of the protrusion 52 is adapted to the inner diameter of the first through hole, allowing it to extend into the first through hole. The fixing base 51 is pressed against the surface of the oven shell 1 and covers the periphery of the first through hole, ensuring the stability of the fixing base 5. The second through hole 53 passes through the fixing base 51 and the protrusion 52, and the inner diameter of the second through hole 53 is designed as a variable diameter structure: specifically, the inner diameter of its inlet end is larger than the inner diameter of its outlet end, and the inner diameter of its outlet end matches the outer diameter of the heating tube 4. The large space at the inlet end is provided for installing the sealing part 6.

[0038] See Figure 7 , Figure 8 and combined Figure 4The sealing part 6 includes a first sealing member 61, which is constructed in an annular shape and is fitted onto the heating tube 4, corresponding to the inlet end of the second through hole 53 and the heating tube 4. The longitudinal section of the first sealing member 61 is constructed as a V-shaped structure with a predetermined thickness. The V-shaped structure further includes a first V-shaped surface 611 and a second V-shaped surface 612. The first V-shaped surface 611 is the top surface of the first sealing member 61, and the second V-shaped surface 612 is the bottom surface of the first sealing member 61. The two together form the inner wall structure 613 and the outer wall structure 614 of the first sealing member 61. The inner wall structure 613 fits against the outer wall of the heating tube 4 to form the first sealing surface; the outer surface of the second V-shaped surface 612 engages with the edge of the inlet end of the second through hole 53 to form the second sealing surface. Through this design, the first sealing member 61 can effectively seal between the heating tube 4 and the fixing seat 5.

[0039] In this embodiment, the first sealing element 61 is made of a metal material that is resistant to high temperature and has a certain degree of elasticity, preferably brass, to ensure that it can maintain its sealing performance and adapt to thermal deformation in a high-temperature environment.

[0040] Combination Figures 9-11 The pressing part 7 is fitted onto the heating tube 4 through a third through hole located at its center, and is locked and fixed to the fixing seat 5 by a locking member 8. Simultaneously, it can press the first sealing member 61 onto the fixing seat 5 to further ensure a sealing effect. Specifically, the pressing part 7 includes a pressing plate 71, which has multiple threaded holes circumferentially. The pressing plate 71 can be locked by screwing the locking member 8 (such as a screw) into the threaded holes. An annular protrusion 72 is fixedly provided at the bottom of the pressing plate 71 along the outer periphery of the third through hole. The longitudinal section of this annular protrusion 72 is also constructed as a V-shaped structure. It should be noted that the V-shaped length L1 of the longitudinal section of the annular protrusion 72 matches the V-shaped length L2 of the longitudinal section of the first seal 61, and the V-shaped angle α of the longitudinal section of the annular protrusion 72 is greater than the V-shaped angle β of the first V-shaped surface 611. This angle difference design makes it possible that when the pressing part 7 initially abuts against the first seal 61, there is a small area of ​​contact between the inclined surface of the annular protrusion 72 and the inclined surface of the first V-shaped surface 611 of the first seal 61, while a tiny gap 9 is formed between the bottom tip of the annular protrusion 72 and the top surface of the first V-shaped surface 611.

[0041] The sealing process is as follows: When the pressing plate 71 is screwed and pressed against the fixing seat 5, since α > β, the two inclined surfaces of the annular protrusion 72 will preferentially compress against the two inner surfaces of the first V-shaped surface 611. As the pressing force increases, the annular protrusion 72 expands the V-shaped opening of the first sealing element 61, causing the V-shaped angle of the first sealing element 61 to tend to increase. This tendency is converted into the overall radial pressure of the first sealing element 61: the inward radial force makes the first sealing surface of the first sealing element 61 fit more tightly against the outer wall of the heating tube 4; the outward radial force makes the second sealing surface more firmly bite against the edge of the inlet end of the second through hole 53 of the fixing seat 5. The aforementioned initial gap 9 provides the necessary space for the elastic deformation of the first sealing element 61, ensuring that the deformation process is smooth and controllable, and enhancing the adaptability and reliability of the seal.

[0042] Preferably, the angle difference between α and β is set between 3° and 15°, and more preferably between 5° and 10°. If the angle difference is set too small, the wedging effect of the annular protrusion 72 on the first seal 61 will be poor when the pressing part 7 is pressed down, requiring a very large axial locking force to achieve a sufficient radial sealing effect for the first seal 61. If the angle difference is set too large, even a small axial locking displacement will cause a huge radial deformation of the first seal 61, which may easily lead to deformation or cracking at the root of the first seal 61, and will also make the assembly process difficult to control.

[0043] In addition, the top of the first V-shaped surface 611 is constructed as an arc-shaped transition structure, which abuts against the annular protrusion 72 of the pressing part 7, which helps to transmit force evenly and reduce local stress concentration.

[0044] The thickness of the first sealing element 61 is set to 1~2mm to balance the sealing strength and deformation capacity. If it is too thin, it may result in insufficient sealing pressure and insufficient strength. If it is too thick, it may require a larger clamping force and have poor elastic deformation capacity.

[0045] The heating tube sealing mechanism provided in this embodiment provides structural support and positioning through the fixed seat 5. The sealing part 6 achieves multi-directional sealing through the V-shaped structure, while the pressing part 7, through the angle difference design with the sealing part 6, causes the axial force of the pressing part 7 to be converted into the radial pressing force of the sealing part 6, together ensuring long-term sealing stability under high temperature and negative pressure conditions.

[0046] Example 2

[0047] This embodiment discloses a heating tube sealing mechanism, which has a roughly the same structure as that in Embodiment 1. For the sake of brevity, only the differences are described in detail here.

[0048] See Figure 4 and Figure 6In this embodiment, the second through hole 53 of the fixing base 5 includes a large through hole 531 with a larger inner diameter and a small through hole 532 with a smaller inner diameter, and the two through holes are coaxially arranged. The inner diameter of the small through hole 532 matches the outer diameter of the heating tube 4. The large through hole 531 is connected to the small through hole 532, and the large through hole 531 is constructed as a frustum-shaped space. When the heating tube 4 extends into the second through hole 53, a wedge-shaped space is formed between the heating tube 4 and the large through hole 531.

[0049] In this embodiment, the sealing part 6 further includes a second sealing member 62. The second sealing member 62 is sleeved on the heating tube 4 and abuts against the bottom surface of the first sealing surface. The shape of the second sealing member 62 matches the wedge-shaped space described above. When the first sealing member 61 is subjected to force under the action of the pressing part 7, the second sealing member 62 can bear and disperse part of the axial force from the first sealing member 61 and convert it into its own displacement tendency toward the small end of the wedge-shaped space, thereby generating a radial clamping force on the heating tube 4, further enhancing the sealing effect.

[0050] Furthermore, in this embodiment, the second seal 62 is also configured as a support base for the first seal 61. When the pressing force is transmitted through the first seal 61, part of the force will be absorbed by the second seal 62, thereby reducing the deformation amplitude and stress level of the bottom area of ​​the first seal 61, and ensuring the uniformity and stability of the contact pressure between the second sealing surface and the fixed seat 5.

[0051] The second seal 62 may be made of a material that has excellent self-lubricating properties and plasticity self-adaptation at high temperatures, such as flexible graphite or a specific high-temperature alloy.

[0052] The heating tube sealing mechanism provided in this embodiment uses a first sealing element 61 as the main seal, which generates the main radial sealing force under the action of the pressing part 7. The second sealing element 62 serves as a cooperative seal, which improves the stress state of the first sealing element 61 through mechanical support and extends its service life. At the same time, even if the first sealing element 61 experiences minor failure under extreme working conditions, the second sealing element 62 can still maintain an effective seal.

[0053] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A heating tube sealing mechanism for a vacuum oven, wherein the shell (1) of the oven is provided with a first through hole, characterized in that, include: The fixing base (5) is connected to the first through hole of the housing (1) and has a second through hole (53) through which the heating tube (4) passes; A sealing part (6) is sleeved on the heating tube (4) and disposed between the heating tube (4) and the inner wall of the second through hole (53); The pressing part (7) is sleeved on the heating tube (4) and is used to press the sealing part (6) onto the fixing seat (5); The sealing part (6) includes a first sealing element (61) and a second sealing element (62). The longitudinal section of the first sealing element (61) is constructed as a V-shaped structure with a predetermined thickness. The pressing part (7) is provided with an annular protrusion (72) with a V-shaped longitudinal section. The V-angle α of the annular protrusion (72) is greater than the V-angle β of the first sealing element (61). The second sealing element (62) is sleeved on the heating tube (4) and abuts against the bottom of the first sealing element (61). The second through hole (53) and the heating tube (4) form a wedge-shaped space. The shape of the second sealing element (62) matches the wedge-shaped space. The V-shaped structure of the first sealing element (61) includes a first V-shaped surface (611) and a second V-shaped surface (612), which together form the inner wall structure (613) and the outer wall structure (614) of the first sealing element (61). The inner wall structure (613) is attached to the outer wall of the heating tube (4) to form a first sealing surface, and the outer side of the second V-shaped surface (612) is engaged with the edge of the inlet end of the second through hole (53) to form a second sealing surface.

2. The heating tube sealing mechanism according to claim 1, characterized in that, The top of the first V-shaped surface (611) is constructed as an arc-shaped transition structure.

3. The heating tube sealing mechanism according to claim 1, characterized in that, The thickness of the first seal (61) is 1-2 mm.

4. The heating tube sealing mechanism according to claim 1, characterized in that, The first seal (61) is made of a high-temperature resistant elastic metal material.

5. The heating tube sealing mechanism according to claim 1, characterized in that, The pressing part (7) is locked and fixed to the fixing base (5) by the locking member (8).

6. The heating tube sealing mechanism according to claim 1, characterized in that, The inner diameter of the inlet end of the second through hole (53) is larger than the inner diameter of the outlet end, forming a variable diameter structure for accommodating the sealing part (6).

7. A vacuum oven, comprising a working cavity enclosed by a shell (1), a heating plate (3) disposed within the working cavity, and a heating tube (4) providing a heat source for the heating plate (3), characterized in that, The heating tube (4) is mounted on the housing (1) by the heating tube sealing mechanism as described in any one of claims 1 to 6.

8. A vacuum parallel seam welding machine, characterized in that, It includes a vacuum chamber and the vacuum oven as described in claim 7, wherein the vacuum oven is fixedly connected to both sides of the vacuum chamber.

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