A telescopic rigid shaft lifting mechanism driven by a single motor

Abstract

The present invention discloses a telescopic hard shaft lifting mechanism driven by a single motor. The outer rod and the inner rod are respectively composed of five outer rod segments and five inner rod segments with different diameters nested from top to bottom in the order of decreasing diameter. The fifth outer rod segment and the fifth inner rod segment are fixedly connected through a linkage boss. The seed crystal chuck is fixedly connected to the lower end surface of the fifth outer rod segment. Between the first inner rod segment and the second inner rod segment, and between the second inner rod segment and the third inner rod segment, they are respectively connected through two locking units. Between the third inner rod segment and the fourth inner rod segment, they are connected through a speed reduction transmission component. The inner rod sleeve is sleeved on the top of the fourth inner rod segment. The planetary gear train is fixedly connected to the inner side wall of the inner rod sleeve. The planet carrier is placed on the inner rod sleeve, and the center buckle is placed on the planet carrier. The present invention can effectively reduce the overall centroid of the single crystal furnace, reduce the motor vibration excitation, the screw drive is beneficial to improving the control accuracy of the lifting speed, reduce the fluctuation of the crystal rod growth interface, and improve the crystal rod growth quality.

Description

Technical Field

[0001] The present invention belongs to a hard-axis lifting mechanism in the field of crystal growth equipment, and particularly relates to a telescopic hard-axis lifting mechanism driven by a single motor. Background Art

[0002] As the basic material of integrated circuit products, single-crystalline silicon is the most important semiconductor material, and the Czochralski method is the mainstream method for growing single-crystalline silicon rods at present. With the continuous improvement of product performance requirements, the single-crystalline silicon used in integrated circuits is developing towards large size and high quality. As the equipment for growing single-crystalline silicon by the Czochralski method, single-crystal furnaces are divided into hard-axis single-crystal furnaces and soft-axis single-crystal furnaces according to different lifting mechanisms. Among them, hard-axis single-crystal furnaces have become the main equipment for growing large-size single-crystalline silicon due to their greater load-bearing capacity.

[0003] The hard-axis single-crystal furnace uses a hollow water-cooled stainless-steel hard pipe to replace the tungsten alloy cable, and the load-bearing capacity is greatly improved. The high rigidity of the hard axis can ensure that the single-crystalline silicon connected to it does not shake significantly at high speeds. Therefore, the hard-axis growth furnace can transfer the lifting speed to the crystal growth interface more accurately.

[0004] However, the lifting mechanism of the mainstream hard-axis single-crystal furnace is a hollow hard pipe several meters long. During the growth of single-crystalline silicon, it needs to be lifted while rotating continuously. It is necessary to use a crystal rotation motor and a crystal lifting motor to drive respectively. At the same time, a rack several meters high needs to be installed above the single-crystal furnace to stabilize the continuously rising hard axis and motor. This makes the overall center of mass of the single-crystal furnace device too high, and it is significantly affected by the motor vibration excitation, resulting in vibration at the crystal growth interface. The temperature gradient at the growth interface is the key to affecting the growth quality of single-crystalline silicon. The liquid level fluctuation caused by the mechanical vibration of the equipment during the lifting process of the seed crystal rod will affect the temperature gradient at the growth interface, thereby affecting the growth rate and quality of single-crystalline silicon. Therefore, how to eliminate the vibration at the crystal growth interface and improve the stability of the device operation is a key technical problem in the research and development of large-size silicon single-crystal growth equipment.

[0005] To ensure the high purity, high uniformity, and high integrity of large-size single-crystalline silicon, it is necessary to study the transmission, mechanical stability technology, and device design of the lifting system of the large-size single-crystalline silicon hard-axis Czochralski growth furnace to reduce the overall center of mass of the equipment and improve the overall stability and anti-shaking ability. The prior art lacks a telescopic hard-axis lifting mechanism that can effectively reduce the overall center of mass of the single-crystal furnace equipment and reduce external excitation. Summary of the Invention

[0006] In order to solve the problems in the background art, the purpose of the present invention is to design a telescopic hard-axis lifting mechanism driven by a single motor. The present invention can effectively reduce the overall center of mass of the single-crystal furnace equipment and reduce external excitation. The technical solution of the present invention is as follows:

[0007] It includes a hollow columnar outer rod, a hollow columnar inner rod, a seed crystal chuck, a speed reduction transmission component and a locking unit; the inner rod is coaxially arranged inside the outer rod, the seed crystal chuck is located outside the outer rod and fixedly connected to the outer bottom surface of the outer rod, the speed reduction transmission component is fixedly installed on the inner rod, the locking unit is fixedly connected to the side wall of the inner rod, the outer rod is externally connected to a motor and is rotatably and movably connected to the external single crystal furnace frame, and the inner rod is fixedly connected to the single crystal furnace frame.

[0008] The outer rod is mainly composed of five hollow columnar outer rod sections with different diameters nested in sequence from top to bottom in the order of decreasing diameter. The five outer rod sections are, from top to bottom, the first outer rod section, the second outer rod section, the third outer rod section, the fourth outer rod section and the fifth outer rod section. The first outer rod section is a hollow columnar structure with an open bottom end and a semi-closed top end, and the fifth outer rod section is a hollow columnar structure with a closed bottom end and an open top end. The inner diameter size of the upper outer rod section matches the outer diameter size of the lower outer rod section. The first outer rod section is externally connected to a motor and is rotatably and movably connected to the single crystal furnace frame.

[0009] The inner rod is mainly composed of five hollow columnar inner rod sections with different diameters nested in sequence from top to bottom in the order of decreasing diameter. The five inner rod sections are, from top to bottom, the first inner rod section, the second inner rod section, the third inner rod section, the fourth inner rod section and the fifth inner rod section. The inner diameter size of the upper inner rod section matches the outer diameter size of the lower inner rod section. The inner rod also includes a furnace cover with both ends open. The opening at the lower end of the furnace cover is communicated with the opening at the upper end of the first inner rod section, and the opening at the upper end of the furnace cover is communicated with the opening at the upper end of the first outer rod section. The furnace cover is fixedly connected to the single crystal furnace frame.

[0010] The lower end surface of the fifth outer rod section and the lower end surface of the fifth inner rod section are fixedly connected through a linkage boss. The seed crystal chuck is located outside the fifth outer rod section and is fixedly connected to the outer bottom surface of the fifth outer rod section. The first inner rod section and the second inner rod section, and the second inner rod section and the third inner rod section are respectively connected through two locking units. The third inner rod section and the fourth inner rod section are connected through a speed reduction transmission component.

[0011] On the outer side walls at the tops of the second outer rod section, the third outer rod section, the fourth outer rod section and the fifth outer rod section, three sliders are arranged at intervals along the circumferences of their own. On the inner side walls of the first outer rod section, the second outer rod section, the third outer rod section and the fourth outer rod section, three chutes are arranged at intervals along the circumferences of their own. And each chute is arranged along the axial direction of the outer rod section itself. Each chute includes a long strip-shaped groove and a trapezoidal side groove. The side groove is located on one side of the upper part of the long strip-shaped groove. The long strip-shaped groove and the side groove are communicated to form the chute. The width of the slider matches the width of the long strip-shaped groove.

[0012] The inner side walls of the first inner rod section, the second inner rod section, the third inner rod section, and the fourth inner rod section are all provided with trapezoidal internal threads. The outer side walls at the tops of the second inner rod section, the third inner rod section, and the fifth inner rod section are all provided with trapezoidal external threads. The lower end faces of the first inner rod section and the second inner rod section are both provided with buckle locks. On one side of the buckle lock close to the central axis direction of the inner rod section, there is a strip-shaped buckle lock groove. Below the trapezoidal external threads in the second inner rod section and the third inner rod section, there are both strip-shaped buckle block grooves. The buckle block grooves and the buckle locks are used to install the locking unit;

[0013] On the inner side wall of the second inner rod section, there are three support buckle grooves arranged at intervals along its circumferential direction. Each support buckle groove is arranged along the axial direction of the second inner rod section. There is a support buckle in the support buckle groove. On the inner side wall of the third inner rod section, there are three grooves arranged at intervals along its circumferential direction. Each groove is arranged along the axial direction of the third inner rod section. The fourth inner rod section is a hollow columnar structure with a through hole in the middle of the upper end face and a fully open lower end. A columnar boss is installed on the upper end face of the fourth inner rod section, and a first through groove is opened in the middle of the columnar boss.

[0014] The described speed reduction transmission assembly includes a hollow columnar inner rod sleeve, a planetary gear train, a planet carrier, and a central buckle; the inner rod sleeve is sleeved on the top of the fourth inner rod section. The outer side wall of the inner rod sleeve is provided with external threads. The third inner rod section is connected to the fourth inner rod section through the external threads on the inner rod sleeve. The planetary gear train is placed on the upper end face of the fourth inner rod section and is fixedly connected to the inner side wall at the top of the inner rod sleeve. The planet carrier is placed on the inner rod sleeve. There is a second through groove in the middle of the planet carrier. The bottom end of the central buckle sequentially passes through the second through groove of the planet carrier, the first through groove of the columnar boss, and the through hole on the upper end face of the fourth inner rod section and then is located inside the fourth inner rod section. The top end of the central buckle is located above the planet carrier.

[0015] The described planetary gear train includes a sun gear, three planet gears, and a ring gear. The sun gear with a smaller diameter is coaxially placed on the inner circumference of the upper end face of the fourth inner rod section. The ring gear with a larger diameter is coaxially placed on the outer circumference of the upper end face of the fourth inner rod section and is fixedly connected to the inner side wall of the top of the inner rod sleeve. The three planet gears are arranged at intervals between the sun gear and the ring gear. The planet carrier includes a triangular frame in the middle, sliding rods, a cylindrical platform, and a crescent-shaped lower engaging tooth. The three sliding rods are respectively fixedly connected to the three corners of the triangular frame. A cylindrical platform is provided at the junction of the triangular frame and the sliding rods on the lower surface of the planet carrier, and the cylindrical platform is located in the middle of the planet gears. A second through groove is provided in the middle of the triangular frame, and several crescent-shaped lower engaging teeth are provided on the upper surface of the triangular frame. The central buckle is an I-shaped columnar structure, which includes a disc, crescent-shaped upper engaging teeth, a columnar block, and a raised square block. Two discs are provided on the upper part of the columnar block, and the two discs are connected by a spring. Several crescent-shaped upper engaging teeth are provided on the lower surface of the disc located below. Three raised square blocks are provided on the outer side surface of the middle part of the columnar block. The disc is located above the triangular frame. The raised square blocks sequentially pass through the second through groove of the triangular frame, the top of the first through groove in the columnar boss, and then contact the lower part of the columnar boss. The lower end of the columnar block sequentially passes through the second through groove of the triangular frame, the first through groove of the columnar boss, and the through hole on the upper end face of the fourth inner rod section and is located inside the fourth inner rod section.

[0016] The described locking unit includes a locking slider and a locking buckle ring; the locking slider and the locking buckle ring are fixedly connected. The locking slider is arranged in the buckle block groove, and the locking buckle ring is connected to the locking groove of the buckle lock.

[0017] Three linkage holes are provided on the lower end face of the fifth inner rod section. The bottom end of the linkage boss passes through the linkage holes and is fixed on the inner bottom surface of the fifth outer rod section. The top end of the linkage boss is connected to the inner bottom surface of the fifth inner rod section.

[0018] The outer rod of the present invention is composed of several hollow cylindrical outer rod sections connected by a slider rail. The uppermost outer rod section is driven by a motor and rotates; the inner rod is composed of several hollow cylindrical inner rod sections connected by threads. The outer rod and the inner rod are connected at the bottom by a linkage boss, so that the inner rod and the outer rod rotate and expand synchronously. The uppermost inner rod section is fixed to the single crystal furnace frame. The inner rod sections connected by threads expand and contract when rotating, and at the same time drive the outer rod to expand and contract synchronously. The relationship between the rotation speed and the expansion and contraction speed is adjusted by setting the thread pitch. The speed reduction transmission mechanism is composed of a planetary gear train and an inner rod sleeve, and is located between two inner rod sections for reducing the expansion and contraction speed. The locking structure includes a locking buckle ring and a locking slider, which are used to prevent the unstable lifting speed caused by the simultaneous rotation of multiple inner rod sections. The present invention relies on a single motor to complete the rotation and upward movement during the lifting process, which can effectively reduce the overall centroid of the single crystal furnace, reduce the motor vibration excitation, the screw drive is beneficial to improving the control accuracy of the lifting speed, reducing the fluctuation of the crystal rod growth interface, and improving the crystal rod growth quality.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1. The present invention uses the telescoping of multiple rods to replace the rising and falling of a common rigid shaft, effectively reducing the overall centroid height of the equipment; relying on screw rotation to achieve the lifting of the seed crystal can improve the control accuracy of the pulling speed; the inner side of the outer rod section is provided with a side groove, which facilitates the nested installation of the outer rod section and avoids the separation of the outer rod sections during the contraction process; the inner rod sections are connected by threads, and the pulling speed of crystal growth at different stages can be determined by setting the thread pitch; the seed crystal chuck is provided with three layers of through holes and notches, which is convenient for the installation and disassembly of the seed crystal.

[0021] 2. A linkage boss and a linkage hole are provided between the outer rod and the inner rod of the present invention. While realizing the functions of the outer rod driving the inner rod to rotate and the inner rod driving the outer rod to lift, it is convenient for the installation of the inner and outer rods, avoids drilling holes in the outer rod, and ensures the sealing performance; since the required pulling speeds at different stages during the crystal growth process vary greatly, a speed reduction transmission device is provided between the inner rod sections, which can effectively reduce the contraction speed of the lifting mechanism and facilitate the control of the pulling speed at each stage during crystal growth.

[0022] 3. A locking device is provided between the inner rod sections of the present invention to prevent the lower inner rod section from driving other inner rod sections to rotate synchronously due to the friction between the threads during rotation, resulting in an uncontrollable pulling speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a structural diagram of the present invention;

[0024] Figure 2 is a schematic diagram of the second outer rod section of the present invention

[0025] Figure 3 is a schematic diagram of the second inner rod section of the present invention;

[0026] Figure 4 is a schematic diagram of the bracket buckle of the present invention;

[0027] Figure 5 is a schematic diagram of the third inner rod section of the present invention;

[0028] Figure 6 is a schematic diagram of the fourth inner rod section of the present invention;

[0029] Figure 7 is an assembly schematic diagram of the speed reduction transmission component and the fourth inner rod section of the present invention;

[0030] Figure 8 is a schematic diagram of the planetary gear train of the present invention;

[0031] Figure 9 is a schematic diagram of the planet carrier of the present invention;

[0032] Figure 10Cross-sectional view of the central buckle and the planet carrier of the present invention;

[0033] Figure 11 Schematic diagram of the central buckle of the present invention;

[0034] Figure 12 Schematic diagram of the locking unit of the present invention;

[0035] Figure 13 Schematic diagram of the locking slider of the present invention;

[0036] Figure 14 Schematic diagram of the locking buckle of the present invention;

[0037] Figure 15 Assembly drawing of the fifth outer rod section and the seed crystal chuck of the present invention;

[0038] Figure 16 Schematic diagram of the fifth inner rod section of the present invention;

[0039] Figure 17 Schematic diagram of the seed crystal chuck of the present invention;

[0040] In the figure: 1. Outer rod; 11. First outer rod section; 12. Second outer rod section; 13. Third outer rod section; 14. Fourth outer rod section; 15. Fifth outer rod section; 16. Chute; 161. Side groove; 18. Linking boss; 181. Circular convex disk; 182. Circular convex column; 19. Slider; 2. Inner rod; 21. First inner rod section; 22. Second inner rod section; 23. Third inner rod section; 24. Fourth inner rod section; 25. Fifth inner rod section; 211. Furnace cover; 241. Columnar boss; 242. First through groove; 26. Linking hole; 261. Circular through hole; 262. Arc-shaped groove; 231. Frame groove; 221. Frame buckle groove; 27. Buckle block groove; 28. Buckle lock; 3. Seed crystal chuck; 34. Seed crystal slot opening; 4. Reduction drive assembly; 41. Inner rod sleeve; 42. Planetary gear train; 43. Central buckle; 421. Central gear; 422. Planet gear; 423. Ring gear; 424. Planet carrier; 425. Slide rod; 426. Crescent-shaped lower buckle teeth; 431. Crescent-shaped upper buckle teeth; 432. Raised square block; 5. Locking unit; 51. Locking slider; 52. Locking buckle ring. Detailed implementation manners

[0041] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0042] As Figure 1As shown in the figure, the mechanism includes a hollow columnar outer rod 1, a hollow columnar inner rod 2, a seed crystal chuck 3, a speed reduction transmission component 4, and a locking unit 5; the inner rod 2 is coaxially arranged inside the outer rod 1, the seed crystal chuck 3 is located outside the outer rod 1 and fixedly connected to the outer bottom surface of the outer rod 1, the seed crystal chuck 3 is used for installing a seed crystal, the speed reduction transmission component 4 is fixedly installed on the inner rod 2, the locking unit 5 is fixedly connected to the side wall of the inner rod 2, the outer rod 1 is externally connected to a motor and rotatably movably connected to the external single crystal furnace frame, and the inner rod 2 is fixedly connected to the single crystal furnace frame.

[0043] As Figure 1 shown in the figure, the outer rod 1 is mainly composed of five hollow columnar outer rod segments nested in sequence from top to bottom in the order of decreasing diameter. The five outer rod segments are the first outer rod segment 11, the second outer rod segment 12, the third outer rod segment 13, the fourth outer rod segment 14, and the fifth outer rod segment 15 from top to bottom. The first outer rod segment 11 is a hollow columnar structure with an open bottom end and a semi-closed top end. The fifth outer rod segment 15 is a hollow columnar structure with a closed bottom end and an open top end. The inner diameter of the upper outer rod segment matches the outer diameter of the lower outer rod segment, so that the open bottom end of the upper outer rod segment can communicate with the open top end of the lower outer rod segment, thereby forming a connected hollow structure in the outer rod 1. The first outer rod segment 11 is externally connected to a motor and rotatably movably connected to the single crystal furnace frame, and is driven and rotated by the motor;

[0044] The inner rod 2 is mainly composed of five hollow columnar inner rod segments nested in sequence from top to bottom by threads in the order of decreasing diameter. The five inner rod segments are the first inner rod segment 21, the second inner rod segment 22, the third inner rod segment 23, the fourth inner rod segment 24, and the fifth inner rod segment 25 from top to bottom. The inner diameter of the upper inner rod segment matches the outer diameter of the lower inner rod segment, so that the open bottom end of the upper inner rod segment can communicate with the open top end of the lower inner rod segment, thereby forming a connected hollow structure in the inner rod 2. Moreover, the first outer rod segment 11, the second outer rod segment 12, the third outer rod segment 13, the fourth outer rod segment 14, and the fifth outer rod segment 15 are respectively coaxially arranged inside the first inner rod segment 21, the second inner rod segment 22, the third inner rod segment 23, the fourth inner rod segment 24, and the fifth inner rod segment 25; the inner rod 2 further includes a furnace cover 211 with both ends open. The open end at the lower end of the furnace cover 211 communicates with the open end at the upper end of the first inner rod segment 21, and the open end at the upper end of the furnace cover 211 communicates with the open end at the upper end of the first outer rod segment 11. The furnace cover 211 is fixedly connected to the single crystal furnace frame;

[0045] The lower end surface of the fifth outer rod section 15 and the lower end surface of the fifth inner rod section 25 are fixedly connected through a linkage boss 18. The seed crystal chuck 3 is located outside the fifth outer rod section 15 and is fixedly connected to the outer bottom surface of the fifth outer rod section 15. Between the first inner rod section 21 and the second inner rod section 22, and between the second inner rod section 22 and the third inner rod section 23, they are respectively connected through two locking units 5. The locking unit 5 is used to lock the rotation of the second inner rod section 22 and the third inner rod section 23. Between the third inner rod section 23 and the fourth inner rod section 24, they are connected through a speed reduction transmission assembly 4.

[0046] As Figure 2 shown, on the outer side walls at the tops of the second outer rod section 12, the third outer rod section 13, the fourth outer rod section 14, and the fifth outer rod section 15, three sliders 19 are arranged at intervals along their circumferences. On the inner side walls of the first outer rod section 11, the second outer rod section 12, the third outer rod section 13, and the fourth outer rod section 14, three chutes 16 are arranged at intervals along their circumferences. And each chute 16 is arranged along the axial direction of the outer rod section itself. Each chute 16 includes a long strip-shaped groove and a trapezoidal side groove 161. The side groove 161 is located on one side of the upper part of the long strip-shaped groove. The long strip-shaped groove and the side groove 161 are connected to form the chute 16. The side groove 161 is used to catch the slider 19 to limit the lower outer rod section. The width of the slider 19 matches the width of the long strip-shaped groove, so that the slider 19 on the lower outer rod section is connected to the upper outer rod section through the chute 16 opened in the upper outer rod section.

[0047] As Figure 3 shown, on the inner side walls of the first inner rod section 21, the second inner rod section 22, the third inner rod section 23, and the fourth inner rod section 24, there are trapezoidal internal threads. On the outer side walls at the tops of the second inner rod section 22, the third inner rod section 23, and the fifth inner rod section 25, there are trapezoidal external threads. The sizes of the trapezoidal internal threads and the trapezoidal external threads match, so that the lower inner rod section is connected to the upper inner rod section through threads. On the lower end surfaces of the first inner rod section 21 and the second inner rod section 22, there are buckle locks 28. On one side of the buckle lock 28 close to the central axis direction of the inner rod section, there is a strip-shaped buckle lock groove. Below the trapezoidal external threads in the second inner rod section 22 and the third inner rod section 23, there are strip-shaped buckle blocks 27 opened. The buckle block 27 and the buckle lock 28 are used to install the locking unit 5;

[0048] As Figure 3 and Figure 4 shown, on the inner side wall of the second inner rod section 22, there are three bracket buckle grooves 221 arranged at intervals along its circumference. Each bracket buckle groove 221 is arranged along the axial direction of the second inner rod section 22. In the bracket buckle groove 221, there is a bracket buckle. As Figure 5As shown in the figure, on the inner side wall of the third inner rod section 23, there are three mounting grooves 231 arranged at intervals along its circumferential direction, and each mounting groove 231 is arranged along the axial direction of the third inner rod section 23. Both the support buckle and the mounting groove 231 are used for installing the sliding rod 425 in the planet carrier 424. As Figure 6 As shown in the figure, the fourth inner rod section 24 is a hollow columnar structure with a through hole in the middle of its upper end face and a fully open lower end. In the middle of the upper end face of the fourth inner rod section 24, there is a columnar boss 241 installed. The size of the columnar boss 241 is larger than that of the through hole. In the middle of the columnar boss 241, there is a first through groove 242. The first through groove 242 is a through groove with a larger opening diameter at the upper part and a smaller opening diameter at the lower part. The size of the first through groove 242 matches the size of the through hole on the upper end face of the fourth inner rod section 24. Both the first through groove 242 and the through hole on the upper end face of the fourth inner rod section 24 are used for installing the center buckle 43.

[0049] As Figure 7 As shown in the figure, the speed reduction transmission assembly 4 includes a hollow columnar inner rod sleeve 41, a planetary gear train 42, a planet carrier 424, and a center buckle 43. The inner rod sleeve 41 is sleeved on the top end of the fourth inner rod section 24, and the upper end face of the inner rod sleeve 41 is higher than the upper end face of the fourth inner rod section 24. There is an external thread on the outer side wall of the inner rod sleeve 41. The third inner rod section 23 is connected to the fourth inner rod section 24 through the external thread on the inner rod sleeve 41. The planetary gear train 42 is placed on the upper end face of the fourth inner rod section 24 and is fixedly connected to the inner side wall at the top end of the inner rod sleeve 41. The planet carrier 424 is placed on the inner rod sleeve 41. There is a second through groove in the middle of the planet carrier 424. The size of the second through groove matches the size of the first through groove 242, and both are used for installing the center buckle 43. The bottom end of the center buckle 43 passes through the second through groove of the planet carrier 424, the first through groove 242 of the columnar boss 241, and the through hole on the upper end face of the fourth inner rod section 24 in sequence and is located inside the fourth inner rod section 24. The top end of the center buckle 43 is located above the planet carrier 424. The center buckle 43 is used to lock the rotation of the fourth inner rod section 24.

[0050] As Figure 8 As shown in the figure, the planetary gear train 42 includes a sun gear 421, three planet gears 422, and a ring gear 423. The sun gear 421 with a smaller diameter is coaxially placed on the inner circumference of the upper end face of the fourth inner rod section 24. The ring gear 423 with a larger diameter is coaxially placed on the outer circumference of the upper end face of the fourth inner rod section 24 and is fixedly connected to the inner side wall at the top end of the inner rod sleeve 41. The columnar boss 241 is located in the middle of the sun gear 421. The three planet gears 422 are arranged at intervals between the sun gear 421 and the ring gear 423. The planet gears 422 are used to transmit the torque of the sun gear 421. As Figure 9 and Figure 10As shown, the planet carrier 424 includes a middle tripod, sliding rods 425, a cylindrical platform, and crescent-shaped lower engaging teeth 426. The three sliding rods 425 are respectively fixedly connected to the three corners of the tripod. The three sliding rods 425 are placed on the inner rod sleeve 41. A cylindrical platform is provided at the connection junction of the middle tripod and the sliding rods 425 on the lower surface of the planet carrier 424, and the cylindrical platform is located in the middle of the planet gear 422. The cylindrical platform is used for limiting the planet carrier 424. A second through groove is provided in the middle of the tripod, and several crescent-shaped lower engaging teeth 426 are provided on the upper surface of the tripod, as Figure 11 shown, the central buckle 43 is an I-shaped columnar structure. The central buckle 43 includes a disc, crescent-shaped upper engaging teeth 431, a columnar block, and a raised square block 432. Two discs are provided on the upper part of the columnar block, and the two discs are connected by a spring. Several crescent-shaped upper engaging teeth 431 are provided on the lower surface of the disc located below. Three raised square blocks 432 are provided on the outer side surface of the middle part of the columnar block. The disc is located above the tripod. The raised square blocks 432 sequentially pass through the second through groove of the tripod and the top of the first through groove 242 in the columnar boss 241 and then contact the lower part of the columnar boss 241. The lower end of the columnar block sequentially passes through the second through groove of the tripod, the first through groove 242 of the columnar boss 241, and the through hole on the upper end surface of the fourth inner rod section 24 and is located inside the fourth inner rod section 24.

[0051] As Figures 12 - 14 shown, the locking unit 5 includes a locking slider 51 and a locking buckle ring 52; the locking slider 51 and the locking buckle ring 52 are fixedly connected. The locking slider 51 is arranged in the buckle block groove 27. The locking buckle ring 52 is connected to the buckle lock groove of the buckle lock 28 through a spring. The locking slider 51 is an arc-shaped structure, divided into three layers front and back, with the middle layer having the highest height. The buckle block groove 27 is divided into three layers front and back, with the middle layer having the highest height. The buckle block groove 27 and the locking slider 51 are in a shape that matches.

[0052] As Figure 15 and Figure 16 shown, three linkage holes 26 are provided on the lower end surface of the fifth inner rod section 25. The bottom end of the linkage boss 18 passes through the linkage holes 26 and is fixed on the inner bottom surface of the fifth outer rod section 15. The top end of the linkage boss 18 is connected to the inner bottom surface of the fifth inner rod section 25. The linkage holes 26 are mainly formed by connecting a circular through hole 261 and an arc-shaped groove 262. The linkage boss 18 is mainly composed of a circular convex disc 181 with a larger diameter and a circular convex column 182 with a smaller diameter fixedly connected. The diameter of the circular through hole 261 is slightly larger than the diameter of the circular convex disc 181 in the linkage boss 18. The width of the arc-shaped groove 262 is smaller than the diameter of the circular convex disc 181 and the width of the arc-shaped groove 262 is larger than the diameter of the circular convex column 182. In a specific implementation, the linkage boss 18 is first fixed on the fifth outer rod section 15, and then the fifth inner rod section 25 is placed into the fifth outer rod section 15. After the circular convex disc 181 passes through the circular through hole 261, the fifth inner rod section 25 moves its position so that the circular convex disc 181 is located above the arc-shaped groove 262 to fix the fifth inner rod section 25.

[0053] The specific working process of the present invention is as follows:

[0054] The first outer rod section 11 is placed on the frame and can rotate but not move, and the first inner rod section 21 is fixed to the frame and cannot rotate or move. First, when the mechanism of the present invention is in the extended state and needs to be contracted, the first outer rod section 11 is driven to rotate by the motor. The first outer rod section 11 drives the second outer rod section 12 to rotate through the constraint of the chute 16 and the slider 19, and so on, causing the entire outer rod to rotate synchronously.

[0055] As Figure 12 shown, since the inner rod 2 is in the extended state at this time, the inner side of the locking slider 51 in the second inner rod section 22 is not restricted by the thread of the third inner rod section 23. Therefore, the locking buckle 52 below the first inner rod section 21 pushes the locking slider 51 in the second inner rod section 22 to slide inward. As a result, a part of the locking buckle 52 below the first inner rod section 21 enters the side wall of the second inner rod section 22. At this point, the second inner rod section 22 is fixed to the first inner rod section 21 and will not rotate.

[0056] Similarly, the third inner rod section 23 and the second inner rod section 22 can also complete the connection constraint, and the third inner rod section 23 will not rotate and is in a fixed state.

[0057] Since the slide rod 425 of the planet carrier 424 is located in the frame groove 231 of the third inner rod section 23, the planet carrier 424 is also in a fixed state and will not rotate. At this time, the central buckle 43 will drop, and at the same time, the crescent-shaped lower buckle teeth 426 and the crescent-shaped upper buckle teeth 431 will be locked, so that the central buckle 43 is restricted by the planet carrier 424 and will not rotate. The three protruding raised blocks 432 below the central buckle 43 cooperate with the first through groove 242 at the center of the columnar boss 241 on the fourth inner rod section 24, so that the fourth inner rod section 24 will not rotate and is in a fixed state.

[0058] After the outer rod 1 starts to rotate, the linkage boss 18 on the inner side of the fifth outer rod section 15 enters the arc groove 262 in the linkage hole 26 of the fifth inner rod section 25, thereby driving the fifth inner rod section 25 to rotate. The fifth inner rod section 25 and the fourth inner rod section 24 are threadedly connected, and the fourth inner rod section 24 is in a fixed state. Therefore, when the fifth inner rod section 25 rotates, it will rise at the same time. At the same time, the linkage hole 26 below the fifth inner rod section 25 will drive the linkage boss 18 of the fifth outer rod section 15 to make the fifth outer rod section 15 rise synchronously. When the fifth inner rod section 25 completely enters the fourth inner rod section 24, the thread locking will drive the fourth inner rod section 24 to rotate; at the same time, when the fifth outer rod section 15 enters the fourth outer rod section 14, due to the rotation tendency, the slider 19 on the outer side of the fifth outer rod section 15 will enter the side groove 161 in the inner chute 16 of the fourth outer rod section 14, so that the fifth outer rod section 15 will drive the fourth outer rod section 14 to rise.

[0059] Since the pulling speed required in the equal-diameter stage is very slow, we need to indirectly reduce the pulling speed by reducing the rotation speed of the inner rod through a speed-reducing transmission structure.

[0060] After the fifth inner rod section 25 is completely retracted into the fourth inner rod section 24, the central buckle 43 is pushed upward along the first through groove 242, so that the fixing constraint of the fourth inner rod section 24 is released and it rotates driven by the fifth inner rod section 25. At the same time, the central gear 421 of the speed-reducing transmission assembly 4 rotates synchronously with the fourth inner rod section 24. At this time, the planet carrier 424 is in a fixed state, and the central gear 421 drives the ring gear 423 through the planet gears 422 to rotate at a lower speed with a certain transmission ratio.

[0061] The ring gear 423 is fixed to the inner side of the inner rod sleeve 41 and drives the inner rod sleeve 41 to start rotating. Since the outer thread of the inner rod sleeve 41 is engaged with the inner thread of the third inner rod section 23, the inner rod sleeve 41 will drive the fourth inner rod section 24 to telescopically enter the third inner rod section 23.

[0062] As the inner rod sleeve 41 rises, when the fourth inner rod section 24 is completely retracted into the third inner rod section 23, the outer thread of the inner rod sleeve 41 rotates to the position of the locking slider 51 in the third inner rod section 23, and the outer thread pushes the locking slider 51 outwards, so that the locking snap ring 52 is disengaged from the third inner rod section 23, and the fixing constraint of the third inner rod section 23 is released and it rotates driven by the inner rod sleeve 41.

[0063] After the fourth inner rod section 24 is completely retracted into the third inner rod section 23, the planet carrier 424 enters the carrier buckle groove 221. At this time, the planet carrier 424 is fixed to the second inner rod section 22, and the speed-reducing transmission assembly 4 is still effective.

[0064] After the third inner rod section 23 is completely retracted into the second inner rod section 22, the outer thread of the third inner rod section 23 rotates to the position of the locking slider 51 in the third inner rod section 23, and the outer thread pushes the locking slider 51 outwards, so that the locking snap ring 52 is disengaged from the second inner rod section 22, and the fixing constraint of the second inner rod section 22 is released and it rotates driven by the third inner rod section 23.

[0065] At this time, the planet carrier 424 is still fixed to the second inner rod section 22 and rotates with the second inner rod section 22. Then the speed-reducing transmission assembly 4 fails, and the rotation speed of the second inner rod section 22 will be the same as the rotation speed of the outer rod 1.

[0066] When the second inner rod section 22 is completely retracted into the first inner rod section 21, the crystal taking operation needs to be carried out. As Figure 17 shown, the seed crystal is used to produce the crystal bar. After the crystal bar is generated, the crystal bar and the seed crystal are cut off, the seed crystal is moved upward along the through hole in the seed crystal chuck 3, and then taken out from the seed crystal slot 34 of the seed crystal chuck 3. The new seed crystal is placed into the through hole along the seed crystal slot 34 and then moved downward to complete the installation.

[0067] The motor controls the first outer rod section 11 to rotate in the opposite direction, causing the inner rod 2 to start extending. During the extension process, there is no need to control the speed. Therefore, each inner rod section may rotate and drive the outer rod section to extend.

[0068] When the second inner rod section 22 and the third inner rod section 23 are fully extended, the locking buckle 52 pushes the locking slider 51 to move inward. The locking unit 5 locks the second inner rod section 22 and the third inner rod section 23, and the planet carrier 424 will also be fixed in the carrier groove 231. If the fifth inner rod section 25 has not been fully extended from the fourth inner rod section 24 at this time, and the center buckle 43 is in the lowered state, but due to the rotation direction being opposite to that during contraction, the arc surfaces of the crescent-shaped teeth between the center buckle 43 and the planet carrier 424 will not lock with each other, and the spring between the discs above the center buckle 43 contracts, ensuring that the center buckle 43 and the fourth inner rod section 24 can still rotate and extend normally at this time.

[0069] The above specific embodiments are used to explain and illustrate the present invention, rather than to limit the present invention. Within the spirit and scope of the claims of the present invention, that is, equivalent changes and modifications made in accordance with the protection scope of the present invention and the content of the specification should fall within the protection scope of the present invention.

Claims

1. A telescopic rigid shaft lifting mechanism driven by a single motor, characterized in that: It includes a hollow columnar outer rod (1), a hollow columnar inner rod (2), a seed crystal chuck (3), a speed reduction transmission assembly (4) and a locking unit (5); the inner rod (2) is coaxially arranged inside the outer rod (1), the seed crystal chuck (3) is located outside the outer rod (1) and fixedly connected to the outer bottom surface of the outer rod (1), the speed reduction transmission assembly (4) is fixedly installed on the inner rod (2), the locking unit (5) is fixedly connected to the side wall of the inner rod (2), the outer rod (1) is externally connected to a motor and rotatably movably connected to the external single crystal furnace frame, and the inner rod (2) is fixedly connected to the single crystal furnace frame; The described outer rod (1) is mainly composed of five hollow columnar outer rod sections nested in order from top to bottom according to the decreasing diameter. The five outer rod sections are the first outer rod section (11), the second outer rod section (12), the third outer rod section (13), the fourth outer rod section (14) and the fifth outer rod section (15) from top to bottom. The first outer rod section (11) is a hollow columnar structure with an open bottom end and a semi-closed top end. The fifth outer rod section (15) is a hollow columnar structure with a closed bottom end and an open top end. The inner diameter of the upper outer rod section matches the outer diameter of the lower outer rod section. The first outer rod section (11) is externally connected to a motor and rotatably movably connected to the single crystal furnace frame; The described inner rod (2) is mainly composed of five hollow columnar inner rod sections nested in order from top to bottom according to the decreasing diameter. The five inner rod sections are the first inner rod section (21), the second inner rod section (22), the third inner rod section (23), the fourth inner rod section (24) and the fifth inner rod section (25) from top to bottom. The inner diameter of the upper inner rod section matches the outer diameter of the lower inner rod section; the inner rod (2) also includes a furnace cover (211) with both ends open. The opening at the lower end of the furnace cover (211) communicates with the opening at the upper end of the first inner rod section (21), and the opening at the upper end of the furnace cover (211) communicates with the opening at the upper end of the first outer rod section (11). The furnace cover (211) is fixedly connected to the single crystal furnace frame; The lower end surface of the fifth outer rod section (15) and the lower end surface of the fifth inner rod section (25) are fixedly connected by a linkage boss (18). The seed crystal chuck (3) is located outside the fifth outer rod section (15) and fixedly connected to the outer bottom surface of the fifth outer rod section (15). Between the first inner rod section (21) and the second inner rod section (22), and between the second inner rod section (22) and the third inner rod section (23), they are respectively connected by two locking units (5). Between the third inner rod section (23) and the fourth inner rod section (24), they are connected by a speed reduction transmission assembly (4); The described speed reduction transmission assembly (4) includes a hollow columnar inner rod sleeve (41), a planetary gear train (42), a planet carrier (424), and a central buckle (43); the inner rod sleeve (41) is sleeved on the top end of the fourth inner rod section (24), an external thread is provided on the outer side wall of the inner rod sleeve (41), and the third inner rod section (23) is connected to the fourth inner rod section (24) through the external thread on the inner rod sleeve (41). The planetary gear train (42) is placed on the upper end face of the fourth inner rod section (24) and fixedly connected to the inner side wall at the top end of the inner rod sleeve (41). The planet carrier (424) is placed on the inner rod sleeve (41), a second through groove is provided in the middle of the planet carrier (424), and the bottom end of the central buckle (43) sequentially passes through the second through groove of the planet carrier (424), the first through groove (242) of the columnar boss (241), and the through hole on the upper end face of the fourth inner rod section (24) and is located inside the fourth inner rod section (24), and the top end of the central buckle (43) is located above the planet carrier (424). The described planetary gear train (42) includes a sun gear (421), three planet gears (422), and a ring gear (423). The sun gear (421) with a smaller diameter is coaxially placed on the inner circumference of the upper end face of the fourth inner rod section (24), and the ring gear (423) with a larger diameter is coaxially placed on the outer circumference of the upper end face of the fourth inner rod section (24) and fixedly connected to the inner side wall at the top end of the inner rod sleeve (41). The three planet gears (422) are arranged at intervals between the sun gear (421) and the ring gear (423). The planet carrier (424) includes a middle triangular frame, slide bars (425), a cylindrical platform, and crescent-shaped lower engaging teeth (426). The three slide bars (425) are respectively fixedly connected to the three corners of the triangular frame. A cylindrical platform is provided at the junction of the triangular frame and the slide bars (425) on the lower surface of the planet carrier (424), and the cylindrical platform is located in the middle of the planet gear (422). A second through groove is provided in the middle of the triangular frame, and several crescent-shaped lower engaging teeth (426) are provided on the upper surface of the triangular frame. The central buckle (43) is of an I-shaped columnar structure and includes a disc, crescent-shaped upper engaging teeth (431), a columnar block, and raised square blocks (432). Two discs are provided on the upper part of the columnar block, and the two discs are connected by a spring. Several crescent-shaped upper engaging teeth (431) are provided on the lower surface of the disc located below. Three raised square blocks (432) are provided on the outer side surface of the middle part of the columnar block. The disc is located above the triangular frame, and the raised square blocks (432) sequentially pass through the second through groove of the triangular frame and the top of the first through groove (242) in the columnar boss (241) and then contact the lower part of the columnar boss (241). The lower end of the columnar block sequentially passes through the second through groove of the triangular frame, the first through groove (242) of the columnar boss (241), and the through hole on the upper end face of the fourth inner rod section (24) and is located inside the fourth inner rod section (24). The described locking unit (5) includes a locking slider (51) and a locking buckle (52); the locking slider (51) and the locking buckle (52) are fixedly connected, the locking slider (51) is arranged in the buckle slot (27), and the locking buckle (52) is connected in the buckle slot of the buckle lock (28).

2. The telescopic rigid shaft lifting mechanism driven by a single motor according to claim 1, characterized in that: On the outer side walls at the tops of the second outer rod section (12), the third outer rod section (13), the fourth outer rod section (14) and the fifth outer rod section (15), three sliders (19) are arranged at intervals along the circumferences of the respective rod sections. On the inner side walls of the first outer rod section (11), the second outer rod section (12), the third outer rod section (13) and the fourth outer rod section (14), three chutes (16) are arranged at intervals along the circumferences of the respective rod sections, and each chute (16) is arranged along the axial direction of the outer rod section itself. Each chute (16) includes a long strip-shaped groove and a trapezoidal side groove (161), the side groove (161) is located on one side of the upper part of the long strip-shaped groove, and the long strip-shaped groove and the side groove (161) are communicated to form the chute (16). The width of the slider (19) matches the width of the long strip-shaped groove.

3. The telescopic rigid shaft lifting mechanism driven by a single motor according to claim 1, characterized in that: On the inner side walls of the first inner rod section (21), the second inner rod section (22), the third inner rod section (23) and the fourth inner rod section (24), trapezoidal internal threads are provided. On the outer side walls at the tops of the second inner rod section (22), the third inner rod section (23) and the fifth inner rod section (25), trapezoidal external threads are provided. On the lower end faces of the first inner rod section (21) and the second inner rod section (22), buckle locks (28) are provided. On one side of the buckle lock (28) close to the central axis direction of the inner rod section, a strip-shaped buckle slot is provided. Below the trapezoidal external threads in the second inner rod section (22) and the third inner rod section (23), strip-shaped buckle slots (27) are opened. The buckle slots (27) and the buckle locks (28) are used to install the locking unit (5). On the inner side wall of the second inner rod section (22), three support buckle slots (221) are arranged at intervals along the circumference of the second inner rod section (22), and each support buckle slot (221) is arranged along the axial direction of the second inner rod section (22). In the support buckle slots (221), support buckles are provided. On the inner side wall of the third inner rod section (23), three support slots (231) are arranged at intervals along the circumference of the third inner rod section (23), and each support slot (231) is arranged along the axial direction of the third inner rod section (23). The fourth inner rod section (24) is a hollow columnar structure with a through hole in the middle of the upper end face and a fully open lower end. A columnar boss (241) is installed on the upper end face of the fourth inner rod section (24), and a first through slot (242) is opened in the middle of the columnar boss (241).

4. The telescopic rigid shaft lifting mechanism driven by a single motor according to claim 1, characterized in that: On the lower end face of the fifth inner rod section (25), three linkage holes (26) are provided. The bottom end of the linkage boss (18) passes through the linkage holes (26) and is fixed on the inner bottom surface of the fifth outer rod section (15), and the top end of the linkage boss (18) is connected to the inner bottom surface of the fifth inner rod section (25).

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