Improved diffusion furnace automatic push-pull boat device

Abstract

The utility model discloses an improved diffusion furnace automatic push-pull boat device, which comprises a loading platform and a quartz rod clamping device, the loading platform is provided with a steering wheel steering mechanism, the steering wheel steering mechanism comprises a stepping motor, a steering gear, a speed reducer and a slewing bearing structure, and an aluminum plate is arranged on a chassis of the loading platform and is fixed with the platform. The quartz rod clamping device is carried on a loading platform of the aluminum profile, a quartz rod is fixed through a three-way structure, and a driving motor, a spiral lead screw and a coupler are additionally arranged. And three limit switches, namely a lowest limit switch, a middle limit switch and a horizontal limit switch, are additionally arranged at the rod tail of the quartz rod. According to the utility model, the defects of unreasonable mechanical mechanism and low automation degree of the original device are overcome.

Description

Technical Field

[0001] The utility model relates to an improved diffusion furnace automatic push-pull boat device applied to school teaching practice, in particular to a diffusion furnace. Background Art

[0002] The diffusion furnace uses the diffusion phenomenon of dopant molecules in the high-temperature environment of the diffusion furnace tube to diffuse the dopants in the material to the surface of the crystal and gradually enter the interior of the crystal. As an indispensable experimental equipment in the semiconductor preparation process, it can be used in the teaching practice of semiconductor process internships in colleges and universities. When the diffusion furnace automatic push-pull boat device completed by Beijing University of Technology in 2022 pushes and pulls the quartz boat, the motor on the slide rail drives the clamping part to move, thereby realizing the pushing and pulling of the quartz rod. This device has the defects of unreasonable mechanical structure design and low automation level:

[0003] First, the original device occupies a large area, resulting in low utilization of laboratory space. In addition, the supporting platform is a tower structure, and the placement of the slide rail and drive motor raises the center of gravity of the entire equipment, posing a safety hazard during operation.

[0004] Secondly, the quartz rod can only move in a direction parallel to the slide rail, and the axis of the quartz rod and the quartz tube still need to be manually calibrated, which makes the calibration work more difficult.

[0005] In addition, the temperature control system of the original device and the push-pull operation of the quartz boat cannot be performed simultaneously. The motor that controls the quartz rod and the single-chip microcomputer that controls the diffusion time are independent of each other and cannot achieve coordinated communication.

[0006] At present, the diffusion furnaces used in mass production are generally equipped with a mechanical arm controlled by an optical coupler to complete the automatic push-pull operation. Although this method has a high degree of automation and simple operation, it requires space for the diffusion furnace to install slide rails and mechanical arms. The diffusion furnace originally used for on-campus teaching practice cannot meet this condition. Utility Model Content

[0007] In order to overcome the defects of existing mechanical devices, such as large waste of space resources, potential safety hazards in operation and low degree of automation, the utility model adopts a modular design concept to construct a new quartz rod clamping module and a carrying platform module. The quartz rod mechanism adopts a fixed clamping type and is driven by a spiral screw. The quartz rod can rotate in a vertical plane with the tail of the quartz rod as the center of rotation. The gear train layout of the carrying platform module adopts a four-steering wheel drive and steering carrying mode, which has the ability to move and turn flexibly. This device also simplifies the mechanical structure and lowers the center of gravity of the equipment. The device communicates with the temperature controller of the diffusion furnace. During the push-pull operation, it is connected to the temperature controller through serial port commands to synchronously control the diffusion time and temperature.

[0008] The technical solution adopted by the utility model to solve its technical problems is: an improved automatic push-pull boat device for a diffusion furnace, including a quartz rod clamping device and a carrying platform. The overall assembly of the carrying platform is a four-steering wheel layout, which is a mobile platform driven by four identical steering wheels and built with aluminum profiles into a frame. The steering wheel mechanism includes: a coupling, a travel motor, a reducer, a rubber-coated wheel and a bearing. The quartz rod mechanism is installed on a single-layer frame assembled with aluminum profiles that is exactly the same as the chassis of the carrying platform. The steering wheel is flipped and installed upside down, and the two are fastened together. The complete structure of the quartz rod device is four groups of clamping mechanisms clamped by four quartz rods. The tail end and the horizontal axis adopt a more rigid three-way structure, and the spiral screw mechanism is used to control the horizontal axis so that it can be lifted and lowered vertically while maintaining the horizontal level. Three limit switches are installed to control the range of the rotation angle of the quartz rod.

[0009] The above-mentioned improved diffusion furnace automatic push-pull boat device has a steering wheel steering mechanism on the carrying platform: the steering stepper motor is tightly fixed to the lower end of the aluminum plate in the wheel group (the side of the wheel below the aluminum plate). The steering gear and the reducer are constrained to enable the steering gear to obtain the axial force provided by the reducer. The steering gear is meshed with the outer ring of the slewing bearing, so that the steering gear can accurately transmit the meshing force. The inner ring of the slewing bearing is fixed to the upper end of the aluminum plate in the steering wheel body with a set bolt for support and positioning. The slewing bearing and the steering gear are installed and carried on this aluminum plate and supported and connected by the aluminum plate; the outer ring of the slewing bearing meshing with the steering gear is installed on the chassis of the vehicle body through another aluminum plate and fixed to the vehicle body. When the steering wheel is turned, the other components rotate around the center of the slewing bearing.

[0010] The above improved automatic boat pushing and pulling device for diffusion furnace, the steering gear is driven by a steering motor, and the steering gear is fastened to the motor shaft.

[0011] The above-mentioned improved diffusion furnace automatic push-pull boat device has a quartz rod clamping mechanism: the tail of the quartz rod is fixed to the horizontal axis through a tee connection, and the two ends of the horizontal axis are respectively connected to the inner ring of the bearing fixed on the screw screw nut platform, and the horizontal axis can rotate freely, so that the quartz rod can rotate at any position in the vertical plane. The tail end of the quartz rod moves vertically up and down through the horizontal axis fixed by the tee, thereby driving the tail of the quartz rod to move accordingly. The movement of the horizontal axis controls the screw of the screw screw to rotate so that the nut moves linearly up and down along the screw screw, thereby causing the horizontal bar to move up and down. The two spiral screws pass through a gear respectively and are relatively fixed. A third gear is added between gear one and gear two to mesh with screw gear one and screw gear two. The lower end of screw one is connected to the motor through a coupling. The motor drives the spiral screw to rotate. While the spiral screw rotates, it drives the gear fixed on it to rotate at the same angular velocity. The rotation of this gear can be transmitted to another screw gear through the meshing gear, thereby realizing the synchronous rotation of the two screws and moving the horizontal axis vertically. In the middle of the quartz rod, one end of the fixed-length rope is tied, and the other end of the rope is tied just above the tail end of the quartz rod. In the initial position, the quartz rod is pulled in a horizontal position by the rope. By lowering the position of the horizontal axis, the quartz rod is lowered by the tail end, and the rope traction point is gradually lifted compared to the tail end until the crossbar reaches the lowest position. At this time, the quartz rod is close to vertical. In order to control the rotation range of the quartz rod, a limiter should be installed.

[0012] Furthermore, navigation positioning is controlled by a mirror reflection type photoelectric switch.

[0013] The beneficial effect of the utility model is that the utility model improves the diffusion furnace automatic push-pull boat device, which effectively solves the problems of low space utilization and low automation level of the original device through the modular design of the steering wheel-driven carrying platform and the inclined quartz rod clamping device. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0015] Figure 1 This is the utility model patent;

[0016] Figure 2 For loading platform;

[0017] Figure 3 is a top view of the loading platform;

[0018] Figure 4 is a schematic diagram of a quartz rod clamping mechanism;

[0019] In the figure, 1. stepper motor, 2. steering gear, 3. reducer, 4. aluminum plate, 5. slewing bearing outer ring, 6. slewing bearing inner ring, 7. aluminum plate 2, 8. steering motor, 9. quartz rod, 10. three-way structure, 11. drive motor, 12. screw screw 1, 13. screw screw 2, 14. coupling, 15 minimum limit switch, 16. middle limit switch, 17. horizontal limit switch, 18. quartz hook. DETAILED DESCRIPTION

[0020] The improved automatic push-pull boat device of the diffusion furnace includes a loading platform and a quartz rod clamping device. The loading platform is provided with a steering wheel steering mechanism, which includes a stepper motor 1, a steering gear 2, a reducer 3 and a slewing support structure, wherein the stepper motor 1 is fixed at the lower end of the aluminum plate 4 in the wheel set. The steering gear 2 and the reducer 3 are constrained and matched, and mesh with the outer ring 5 of the slewing support. The inner ring 6 of the slewing support is fixed at the upper end of the aluminum plate 4 of the main body, and the steering gear is mounted on the aluminum plate 4. The aluminum plate 2 7 is installed on the loading platform chassis and fixed to the platform. The steering gear is driven by the steering motor 8, so that the steering gear is fastened to the motor shaft. The quartz rod clamping device is mounted on the loading platform of the aluminum profile, and the quartz rod 9 is fixed by a three-way structure 10. The quartz rod clamping device is equipped with a driving motor 11, a screw screw 1 12, a screw screw 2 13 and a coupling 14. The driving motor 11 is installed directly below the screw screw 12, and the coupling 14 connects the motor shaft with the screw screw. Three limit switches are installed at the end of the quartz rod: the lowest limit switch 15, the middle limit switch 16 and the horizontal limit switch 17. The limit switch is installed at the quartz rod, and the rod head quartz hook 18 falls and hooks the quartz ring at the end of the quartz boat.

Claims

1. An improved automatic push-pull boat device for a diffusion furnace, characterized in that: The invention comprises a loading platform and a quartz rod clamping device. The loading platform is provided with a steering wheel steering mechanism, which comprises a stepping motor (1), a steering gear (2), a reducer (3) and a slewing bearing structure. A second aluminum plate (7) is installed on the loading platform chassis and fixed to the platform. The quartz rod clamping device is mounted on the loading platform of the aluminum profile, wherein the quartz rod (9) is fixed by a three-way structure (10). A driving motor (11), a first screw screw (12), a second screw screw (13) and a coupling (14) are installed. The driving motor (11) is installed just below the first screw screw (12), and the coupling (14) connects the motor shaft with the screw screw. Three limit switches are installed at the end of the quartz rod: a minimum limit switch (15), a middle limit switch (16) and a horizontal limit switch (17). A stepper motor (1) is fixed to the lower end of an aluminum plate (4) in a wheel assembly; a steering gear (2) and a reducer (3) are constrained to cooperate, and the steering gear (2) and a slewing bearing outer ring (5) are meshed; a slewing bearing inner ring (6) is fixed to the upper end of the aluminum plate (4) of the main body, and the steering gear (2) is mounted on the aluminum plate (4).

2. The improved automatic push-pull boat device for diffusion furnace according to claim 1, characterized in that: The limit switch is installed on the quartz rod, and the quartz hook (18) at the head of the quartz rod falls and hooks the quartz ring at the stern of the quartz boat.

3. The improved automatic push-pull boat device for diffusion furnace according to claim 1, characterized in that: Navigation positioning is controlled by mirror reflection photoelectric switches.

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