Workpiece supporting point switching device and chemical vapor deposition furnace

Abstract

The invention discloses a workpiece supporting point switching device, and relates to the technical field of chemical vapor deposition. The supporting assembly is arranged on the end socket assembly and comprises a plurality of supporting columns located above the end socket assembly, and the supporting columns are used for supporting workpieces; the position changing assembly comprises a height switching drive and a plurality of position changing parts, the position changing parts and the supporting columns are arranged in parallel, and the height switching drive can drive the position changing parts to ascend and descend synchronously. The invention further provides a chemical vapor deposition furnace, the chemical vapor deposition furnace comprises a furnace body and the workpiece supporting point switching device, the supporting assembly and the transposition assembly are located in a reaction cavity of the furnace body, and the end socket assembly is plugged at an opening of the reaction cavity. When a workpiece supporting point is replaced, time and labor are saved, and the chemical vapor deposition efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical vapor deposition, and in particular to a workpiece support point switching device and a chemical vapor deposition furnace. Background Art

[0002] Chemical vapor deposition (CVD) is a method that can transport gaseous substances into a reaction chamber, and produce solid deposits by chemically reacting on the surface of the workpiece. When using a chemical vapor deposition furnace, the workpiece to be deposited will be placed on the tooling in the furnace. There will be a contact portion between the tooling and the workpiece, that is, the support point used to support the workpiece. During deposition, due to the obstruction of the support point, the gas phase components cannot reach the contact position, and there will be corresponding gaps in the coating, affecting the integrity of the coating. In order to make the coating complete, the common practice is to manually rearrange the workpiece, expose the original contact position, and then perform secondary deposition; however, the manual rearrangement process is time-consuming and labor-intensive, and requires the furnace to be shut down, which reduces the efficiency of chemical vapor deposition. Summary of the invention

[0003] The purpose of the present invention is to provide a workpiece support point switching device and a chemical vapor deposition furnace to solve the problems existing in the above-mentioned prior art, save time and labor, and improve the efficiency of chemical vapor deposition.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a workpiece support point switching device, comprising:

[0006] Head assembly;

[0007] A support assembly is arranged on the head assembly, the support assembly comprises a plurality of support columns located above the head assembly, and the support columns are used to support the workpiece;

[0008] The transposition assembly comprises a height switching drive and a plurality of transposition parts, wherein the transposition parts are arranged in parallel with the support column, and the height switching drive can drive the plurality of transposition parts to rise and fall synchronously.

[0009] In one embodiment, the support column includes a vertically arranged first column portion, and a plurality of first support portions are sequentially provided along the axial direction on the side wall of the first column portion, and the plurality of first support portions located at the same height can support the same workpiece; the transposition portion includes a transposition column and a direction switching drive, and the transposition column includes a vertically arranged second column portion, and a plurality of second support portions are sequentially provided along the axial direction on the side wall of the second column portion, and the bottom of the second column portion is connected to the direction switching drive, and the direction switching drive can drive the plurality of second column portions to rotate synchronously.

[0010] In one embodiment, a rotating assembly is further included, and the bottom of the supporting assembly is connected to the rotating assembly, and the rotating assembly can drive the supporting assembly to rotate synchronously.

[0011] In one embodiment, the rotating assembly includes a rotating disk arranged above the head assembly, a rotating shaft is fixedly connected to the bottom of the rotating disk, the rotating shaft passes through the head assembly and is transmission-connected to a rotating drive motor, and the rotating drive motor is fixed to the bottom of the head assembly; the supporting assembly is fixed on the rotating disk, and the transposition assembly is located on the outside of the rotating disk.

[0012] In one embodiment, a plurality of guide columns are fixedly provided at the bottom of the head assembly, a connecting plate is movably sleeved on the guide columns, the height switching drive is a linear motion actuator, one end of which is fixed to the bottom of the head assembly, and the other end is connected to the connecting plate; the direction switching drive is arranged at the bottom of the connecting plate, and the bottom of the second column portion passes through the connecting plate and is transmission-connected to the direction switching drive.

[0013] In one embodiment, the linear motion actuator is a pneumatic cylinder, an oil cylinder or an electric push rod.

[0014] In one embodiment, the direction switching drive is a stepper motor, a servo motor or a rotary cylinder.

[0015] In one embodiment, the head assembly includes a head, a heat-insulating layer is fixedly provided on the upper end of the head, and a graphite bottom plate is fixedly provided on the upper end of the heat-insulating layer.

[0016] In one embodiment, the first support portion includes a horizontally arranged connecting rod, a vertically arranged supporting head is fixedly provided at the end of the connecting rod, and the supporting head is a cone-shaped structure; the second support portion has the same structure as the first support portion.

[0017] The present invention also provides a chemical vapor deposition furnace, comprising a furnace body and the workpiece support point switching device as described above, wherein the support assembly and the transposition assembly are located in a reaction chamber of the furnace body, and the head assembly seals the opening of the reaction chamber.

[0018] Compared with the prior art, the present invention has achieved the following technical effects:

[0019] The support column of the support assembly of the present invention is used to support the workpiece. After the initial vapor deposition, there is no need to stop the furnace and manually replace the support point positions of the workpiece and the support column. The transposition part of the transposition assembly can rise to temporarily replace the support column to support the workpiece and expose the support point at the original support column position, so that secondary deposition can be carried out, which saves time and labor and does not require furnace shutdown, thereby improving the efficiency of chemical vapor deposition. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the supporting structure in a chemical vapor deposition furnace in the prior art;

[0022] Figure 2 It is a schematic diagram of a workpiece support point switching device of the present invention;

[0023] Figure 3 It is a cross-sectional schematic diagram of the workpiece support point switching device of the present invention;

[0024] Figure 4 It is a schematic diagram of the lower part of the workpiece support point switching device of the present invention;

[0025] Figure 5 It is a schematic diagram of the state in which the transposition column of the workpiece support point switching device of the present invention rises to lift up the workpiece.

[0026] In the figure: 1-head, 2-insulation layer, 3-graphite bottom plate, 4-rotation assembly, 401-support column, 4011-first column part, 4012-first support part, 402-rotation disk, 403-rotation shaft, 404-rotation drive motor, 5-transposition assembly, 501-transposition column, 5011-second column part, 5012-second support part, 502-connecting plate, 503-guide column, 504-direction switching drive, 505-height switching drive. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The purpose of the present invention is to provide a workpiece support point switching device and a chemical vapor deposition furnace to solve the problems existing in the above-mentioned prior art, save time and labor, and improve the efficiency of chemical vapor deposition.

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] In some fields, the surface of the workpiece used usually needs to be provided with a dense silicon carbide coating, wherein the uniformity and integrity of the coating are important indicators for measuring the quality of the parts, and the chemical vapor deposition method is generally used to coat the surface of the workpiece. The inventors know a chemical vapor deposition furnace, such as Figure 1 As shown, when using a chemical vapor deposition furnace, the workpiece to be deposited will be placed on the tooling in the furnace. There will be a contact portion between the tooling and the workpiece. During deposition, due to the obstruction of the contact portion, the gas phase components cannot reach the contact position, and there will be corresponding gaps in the coating, affecting the integrity of the coating. In order to make the coating complete, the common practice is to stop the furnace after the initial deposition, and then manually rearrange the workpiece to expose the original support point position before performing a secondary deposition. Because the chemical vapor deposition process is usually an intermittent production, the secondary deposition requires the chemical vapor deposition furnace to go through the heating, deposition and cooling processes again, resulting in a waste of energy and production time.

[0031] Based on this, the present invention provides a workpiece support point switching device to improve deposition efficiency. Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, it includes a head assembly, which is used to seal the opening of the chemical vapor deposition furnace, so as to close the reaction chamber in the furnace body; the support assembly is arranged on the head assembly, and the support assembly includes a plurality of support columns 401 located above the head assembly, and the support columns 401 are located in the reaction chamber and are used to support the workpiece; the transposition assembly 5 includes a height switching drive 505 and a plurality of transposition parts, the transposition parts are arranged in parallel with the support columns 401, and the height switching drive 505 can drive the plurality of transposition parts to rise and fall synchronously. After the initial vapor deposition, there is no need to stop the furnace and manually replace the support point position of the workpiece and the support column 401. The height switching drive 505 is used to drive the transposition part of the transposition assembly 5 to rise to temporarily replace the support column 401 to support the workpiece. At this time, the workpiece is lifted up by the transposition part, so that the workpiece is separated from the support column 401, thereby exposing the original support point position of the support column 401, and then the rotating drive motor 404 drives the rotating disk 402 and the support column 401 to rotate a certain angle, and the height switching drive 505 drives the connecting plate 502 to descend, so that the workpiece is supported by the support column 401 again. However, the switching of the support position has been completed at this time, and there is no need to stop the furnace. The secondary deposition can be continued, saving time and effort. Since there is no need to stop the furnace, the efficiency of chemical vapor deposition is improved.

[0032] The above technical solution of the present invention is applicable to when a single workpiece is lifted up by a support column 401 for chemical vapor deposition. When multiple workpieces are arranged in sequence from top to bottom in a chemical vapor deposition furnace at the same time, the above technical solution of the present invention needs to be further optimized. In a preferred embodiment, the support column 401 includes a plurality of first column portions 4011 arranged vertically and arranged in a circle above the head assembly. A plurality of first support portions 4012 are arranged in sequence along the axial direction on the side wall of the first column portion 4011. The plurality of first support portions 4012 at the same height can support the same workpiece, thereby realizing the function of supporting multiple workpieces at the same time, and chemical vapor deposition can be performed on multiple workpieces at the same time. Due to the support of the first support portion 4012 on the workpiece, deposition will also be impossible at the support point.

[0033] In order to be able to change the positions of multiple workpieces at the same time after the initial deposition so that their original support points are exposed, the transposition part is optimized in the present embodiment. The transposition part of the present embodiment includes a transposition column 501 and a direction switching drive 504. The transposition column 501 includes a vertically arranged second column portion 5011. A plurality of second support portions 5012 are sequentially arranged along the axial direction on the side wall of the second column portion 5011. The bottom of the second column portion 5011 is connected to the direction switching drive 504. The direction switching drive 504 can drive the plurality of second column portions 5011 to rotate synchronously. Thus, during the initial deposition, the first support portion 4012 supports the workpiece, at which time the second column portion 5011 is located outside the first column portion 4011, the second support portion 5012 is located outside the second column portion 5011, and the height of the second support portion 5012 is lower than the height of the corresponding first support portion 4012. After the initial deposition is completed, the direction switching drive 504 can be used to control the second column portion 5011 to rotate until the second support portion 5012 is located at the inner position and stops. At this time, the second support portion 5012 is located below the corresponding workpiece, and the second column portion 5011 is raised by the height switching drive 505 until the second support portion 5012 When the height is greater than the height position of the corresponding first support part 4012, the second support part 5012 supports the corresponding workpiece, and the workpiece is separated from the first support part 4012, thereby exposing the original support point of the first support part 4012 on the workpiece, and then the rotation drive motor 404 drives the rotating disk 402 and the support column 401 to rotate a certain angle, and the height switching drive 505 drives the connecting plate 502 to descend, so that the workpiece is supported by the first support part 4012 again, but at this time the switching of the support position has been completed, and the secondary deposition can continue to be performed at the support point. This process does not require the furnace to be stopped and there is no need to manually move the workpiece, thereby improving work efficiency.

[0034] In one embodiment, the first support portion 4012 includes a horizontally arranged connecting rod, and a vertically arranged supporting head is fixedly provided at the end of the connecting rod. The supporting head is a conical structure, which is in point contact with the workpiece, and the coating gap caused by a single deposition is small; the second support portion 5012 has the same structure as the first support portion 4012. In order to facilitate temporary support of the workpiece after rotation without interfering with the rotating disk 402, the length of the connecting rod of the second support portion 5012 is greater than the length of the connecting rod of the first support portion 4012.

[0035] In order to improve the uniformity of the coating, further improvements have been made to this embodiment. During the process of depositing the coating on the workpiece, the workpiece is always rotated slowly, thereby making the coating more uniform. In order to realize this technical solution, in one embodiment, the bottom of the support assembly is connected to the rotating disk 402 of the rotating assembly 4, and the rotating disk 402 is located above the head assembly, and a rotating shaft 403 is fixedly connected to the bottom of the rotating disk 402. After the rotating shaft 403 passes through the head assembly, it is transmission-connected to a rotating drive motor 404. The rotating shaft 403 is connected to the head assembly through a bearing, so that the rotation of the rotating shaft 403 will not be interfered with by the head assembly. A sealing ring and other structures can be set at the end of the bearing to ensure good sealing of the head assembly. The rotary drive motor 404 is fixed to the bottom of the head assembly; in this embodiment, the support assembly is fixed on the rotating disk 402, so that the rotary drive motor 404 controls the rotation of the rotating disk 402, and then drives the support assembly and the workpiece to rotate slowly and synchronously, so that the deposition is more uniform. Since the rotating disk 402 requires a certain rotation space, the transposition assembly 5 is arranged on the outside of the rotating disk 402 in this embodiment, which will not interfere with the rotation process of the rotating disk 402.

[0036] This embodiment adds a rotating disk 402 structure, so when working, one or more workpieces are placed flat on the first support part 4012 of the support column 401, and during the chemical vapor deposition process, the rotary drive motor 404 drives the workpiece to rotate at a uniform speed. At this time, each second support part 5012 is located on the lower side of the corresponding workpiece and outside the circumference of the rotating disk 402, and the second support part 5012 does not interfere with the workpiece. When the first coating process passes the set time, the rotary drive motor 404 stops rotating. The direction switching drive 504 drives the transposition column 501 to rotate, so that the second support part 5012 is transferred to the inner side of the circumference of the rotating disk 402. The height switching drive 505 drives the connecting plate 502 to rise, and then drives each transposition column 501 to rise, so that the second support part 5012 lifts each workpiece away from the first support part 4012. The rotary drive motor 404 rotates a certain angle, and the angle can be designed according to the actual situation of the equipment. The angle in the example of the attached figure can be set to 10-50°. The height switching drive 505 drives the connecting plate 502 to descend, so that the workpiece is supported by the first support part 4012 again, and the support point has changed. The direction switching drive 504 drives the second support part 5012 back to the outside of the circumference of the rotating disk 402, thus completing the switching process of the workpiece support point. Then, the rotary drive motor 404 drives the rotating disk 402 to rotate at a constant speed to continue the chemical vapor deposition process. Because the contact point between the first support part 4012 and the workpiece has changed before and after the switching, subsequent deposition will also occur at the original gap, and the integrity of the workpiece coating can be guaranteed without stopping the furnace. Through the above operations, energy consumption is saved, the production cycle of the workpiece is shortened, and cost reduction and efficiency improvement are achieved.

[0037] In order to adjust the height of the transposition part, in this embodiment, a plurality of guide posts 503 are fixedly provided at the bottom of the head assembly, and a connecting plate 502 is movably sleeved on the guide posts 503. The height switching drive 505 is a linear motion actuator, specifically a cylinder, an oil cylinder or an electric push rod, one end of which is fixed to the bottom of the head assembly, and the other end is connected to the connecting plate 502, so that the connecting plate 502 can be driven to move up and down along the guide posts 503; the direction switching drive 504 is arranged at the bottom of the connecting plate 502, and the bottom of the second column part 5011 is provided with a connecting plate 502. The second column portion 5011 passes through the connecting plate 502 and is connected to the direction switching drive 504. The second column portion 5011 is provided with a bearing at the position of the connecting plate 502, that is, a bearing is provided at the through hole of the connecting plate 502. The bottom of the second column portion 5011 is passed through the bearing and is connected to the direction switching drive 504, so that when the second column portion 5011 rotates, it will not be interfered by the connecting plate 502. The direction switching drive 504 of this embodiment is a stepping motor, a servo motor or a rotary cylinder, which can drive the second column portion 5011 to rotate.

[0038] In a specific embodiment, there are preferably two or more guide columns 503, which are evenly distributed along the circumferential direction of the head 1, so that the connecting plate 502 can move up and down along the axial direction of the guide column 503. The number of direction switching drives 504 can be one or the same as the number of transposition columns 501. The number of transposition columns 501 can be two or three, and the number can also be specifically designed according to needs. When a direction switching drive 504 is set, a synchronous belt or other device can be used to transmit power to the remaining transposition columns 501, that is, one direction switching drive 504 drives multiple transposition columns 501 to rotate. When the number of direction switching drives 504 is the same as the number of transposition columns 501, each transposition column 501 can be independently driven by its own direction switching drive 504.

[0039] Another object of the present invention is to design a chemical vapor deposition furnace, including a furnace body and a workpiece support point switching device as described above, wherein the support assembly and the transposition assembly 5 are located in the reaction chamber of the furnace body, and the head assembly is sealed at the opening of the reaction chamber to form a seal for the reaction chamber. In order to achieve the sealing effect and the heat preservation in the reaction chamber, the head assembly of this embodiment includes a head 1, and an insulation layer 2 is fixedly provided on the upper end of the head 1. The insulation layer 2 can be made of carbon fiber insulation felt or ceramic fiber, refractory fiber, aluminum silicate fiber and the like. The insulation layer 2 is fixedly provided on the upper end of the insulation layer 2. Graphite bottom plate 3, graphite bottom plate 3 is located below the rotating disk 402 and does not contact the rotating disk 402, with a gap therebetween. Graphite bottom plate 3 is used to seal the muffle in the furnace body and protect the thermal insulation material 2 at the same time without interfering with the rotation of the rotating disk 402. The outer diameter of the head 1 is larger than the outer diameters of the thermal insulation layer 2 and the graphite bottom plate 3. The head 1 is sealed at the opening of the furnace body. The thermal insulation layer 2 is located at the opening of the furnace body and extends from the opening of the furnace body into the furnace body. The graphite bottom plate 3 is located in the furnace body, so that the reaction chamber in the furnace body has good overall sealing performance.

[0040] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A workpiece support point switching device, characterized in that: include: Head assembly; A support assembly is arranged on the head assembly, the support assembly comprises a plurality of support columns located above the head assembly, and the support columns are used to support the workpiece; The transposition assembly comprises a height switching drive and a plurality of transposition parts, wherein the transposition parts are arranged in parallel with the support column, and the height switching drive can drive the plurality of transposition parts to rise and fall synchronously.

2. The workpiece support point switching device according to claim 1, characterized in that: The support column includes a vertically arranged first column portion, and a plurality of first support portions are sequentially provided on the side wall of the first column portion along the axial direction, and the plurality of first support portions located at the same height can support the same workpiece; the transposition portion includes a transposition column and a direction switching drive, and the transposition column includes a vertically arranged second column portion, and a plurality of second support portions are sequentially provided on the side wall of the second column portion along the axial direction, and the bottom of the second column portion is connected to the direction switching drive, and the direction switching drive can drive the plurality of second column portions to rotate synchronously.

3. The workpiece support point switching device according to claim 1, characterized in that: It also includes a rotating assembly, the bottom of the supporting assembly is connected to the rotating assembly, and the rotating assembly can drive the supporting assembly to rotate synchronously.

4. The workpiece support point switching device according to claim 3, characterized in that: The rotating assembly includes a rotating disk arranged above the head assembly, a rotating shaft is fixedly connected to the bottom of the rotating disk, the rotating shaft passes through the head assembly and is transmission-connected to a rotating drive motor, and the rotating drive motor is fixed to the bottom of the head assembly; the supporting assembly is fixed on the rotating disk, and the transposition assembly is located outside the rotating disk.

5. The workpiece support point switching device according to claim 2, characterized in that: A plurality of guide columns are fixedly provided at the bottom of the head assembly, and a connecting plate is movably sleeved on the guide columns. The height switching drive is a linear motion actuator, one end of which is fixed to the bottom of the head assembly, and the other end is connected to the connecting plate; the direction switching drive is arranged at the bottom of the connecting plate, and the bottom of the second column portion passes through the connecting plate and is transmission-connected to the direction switching drive.

6. The workpiece support point switching device according to claim 5, characterized in that: The linear motion actuator is an air cylinder, an oil cylinder or an electric push rod.

7. The workpiece support point switching device according to claim 2, characterized in that: The direction switching drive is a stepping motor, a servo motor or a rotary cylinder.

8. The workpiece support point switching device according to claim 1, characterized in that: The end cap assembly comprises an end cap, a heat preservation layer is fixedly disposed on the upper end of the end cap, and a graphite bottom plate is fixedly disposed on the upper end of the heat preservation layer.

9. The workpiece support point switching device according to claim 2, characterized in that: The first support portion comprises a horizontally arranged connecting rod, a vertically arranged supporting head is fixedly provided at the end of the connecting rod, and the supporting head is a cone-shaped structure; the second support portion has the same structure as the first support portion.

10. A chemical vapor deposition furnace, characterized in that: It comprises a furnace body and a workpiece support point switching device as claimed in any one of claims 1 to 9, wherein the support assembly and the transposition assembly are located in a reaction chamber of the furnace body, and the head assembly is sealed at the opening of the reaction chamber.

Images