A z-axis moving mechanism

Abstract

The utility model discloses a kind of Z-axis moving mechanism, comprising: fixed seat, the fixed seat includes chassis and the vertical plate connected with the chassis;Moving seat, the moving seat is slidably connected with the fixed seat by linear guide assembly;Driving assembly, the driving assembly includes servo motor, meshing wheel and rack, the servo motor is installed on the moving seat, the meshing wheel is transmission connection with the output end of the servo motor, the rack is fixedly installed on the vertical plate of the fixed seat, and is engaged with the meshing wheel;The utility model uses servo motor to drive meshing wheel rack transmission, servo motor is installed on moving seat, rack is fixed on fixed seat.This "motor, static rack" driving mode effectively avoids deformation of rack itself due to self-weight or installation accuracy in long-stroke transmission, so that transmission is more stable, response speed is fast, so that higher positioning accuracy and transmission efficiency can be realized.

Description

Technical Field

[0001] This utility model relates to the field of exposure equipment technology, and in particular to a Z-axis moving mechanism. Background Technology

[0002] In the high-precision industrial production of integrated circuits, the exposure machine is one of the core pieces of equipment, requiring extremely high precision and stability. During the operation of the exposure machine, the worktable performs precise and rapid positioning and repetitive movements in the Z-axis direction. The Z-axis moving mechanism is a key component for achieving photolithography focusing and adjusting the exposure distance, directly affecting exposure quality and production efficiency.

[0003] Existing Z-axis movement mechanisms typically employ lead screw drives, but these solutions have several technical drawbacks. For example, while lead screw drives are relatively simple in structure, they suffer from low transmission efficiency and uneven transmission, affecting vertical positioning accuracy and failing to meet the demands of high-precision, high-speed applications. Therefore, there is an urgent need in this field for a novel Z-axis movement mechanism capable of addressing these issues. Utility Model Content

[0004] To solve the above problems, this utility model provides the following technical solution: A Z-axis moving mechanism, comprising: A fixed base, the fixed base including a chassis and an upright plate connected to the chassis; A movable seat, wherein the movable seat and the fixed seat are slidably connected via a linear guide assembly; The drive assembly includes a servo motor, a meshing wheel, and a rack. The servo motor is mounted on the movable base, the meshing wheel is connected to the output end of the servo motor, and the rack is fixedly mounted on the upright plate of the fixed base and meshes with the meshing wheel.

[0005] As a further embodiment of this utility model, it also includes a limiting system, which includes a limiting window opened on the upright plate of the fixed base, at least two position sensors disposed on the upper and lower sides of the limiting window, and a triggering component fixedly disposed on the movable base and extending into the limiting window to control the position sensors. The triggering component includes a limiting block fixedly installed on the movable base and extending into the limiting window, and a light-shielding plate disposed on the limiting block. When the movable base moves to a preset limit position, the light-shielding plate is adapted to enter the sensing area of ​​the corresponding position sensor to trigger a signal. The top of the limiting block is provided with a first buffer pad, which is adapted to contact the upper edge of the limiting window.

[0006] As a further improvement of this utility model, the limiting system further includes a second buffer pad, which is disposed on the chassis of the fixed seat and located at the lower end of the moving path of the movable seat.

[0007] As a further embodiment of this utility model: the linear guide assembly includes at least one linear guide rail fixedly installed on the upright plate, and a slider slidably disposed on the linear guide rail and fixedly connected to the movable seat.

[0008] As a further improvement of this utility model: the number of linear guide rails is two, and the two linear guide rails are arranged parallel to each other on the upright plate.

[0009] As a further embodiment of this utility model: the movable seat includes a first part and a second part connected to each other, the first part being used to bear the load, and the second part being connected to the linear guide assembly and the drive assembly.

[0010] As a further embodiment of this utility model: the movable seat is L-shaped, the first part is a horizontally arranged horizontal plate, the second part is a vertically arranged vertical plate, and the horizontal plate is connected to one end of the vertical plate.

[0011] As a further improvement of this utility model: the horizontal plate is provided with a mounting groove, the servo motor is accommodated in the mounting groove, and is connected to the meshing wheel through a reducer.

[0012] As a further embodiment of this utility model, it also includes a position detection component, which includes a grating ruler disposed on the fixed base and a reading head disposed on the movable base and disposed opposite to the grating ruler.

[0013] As a further embodiment of this utility model: the grating ruler is vertically fixed to the upright plate, and the reading head is fixed to the movable base.

[0014] Compared with existing technologies, the advantages of this invention are: smooth transmission, high efficiency, and high precision. This invention uses a servo motor to drive a meshing gear rack transmission, with the servo motor mounted on a movable base and the rack fixed on a fixed base. This "moving motor, stationary rack" driving method effectively avoids deformation of the rack itself due to its own weight or installation precision during long-stroke transmission, resulting in smoother transmission and faster response, thereby achieving higher positioning accuracy and transmission efficiency.

[0015] Compact structure and space saving: The servo motor is directly mounted on the moving base, making the entire drive component more integrated. There is no need for additional space to install the motor and complex transmission connectors, which is conducive to the compact design of the Z-axis mechanism. It is especially suitable for high-precision equipment with limited space, such as exposure machines.

[0016] Multiple redundant safety limit switches ensure high reliability: A limit system is introduced, using limit windows, trigger components, and position sensors to achieve limit position detection, realizing non-contact, highly reliable hard limit protection. When the moving part exceeds its normal operating range, the trigger component enters the limit window and triggers the position sensor to issue an alarm or stop signal, effectively preventing over-limit movement. This limit system provides redundancy with feedback from conventional encoders or linear scales, ensuring ultimate safety even if the main control system or position detection components fail.

[0017] Buffer protection to prevent mechanical damage: The trigger assembly is equipped with a buffer pad, and the limit system can also integrate a second buffer pad at the lower end of the movement path, forming a multi-level buffer. When the mechanism accidentally exceeds its limit position, the buffer pad can absorb the impact energy, preventing a hard collision between the moving seat and the fixed seat, effectively protecting the mechanical structure and load of the mechanism, extending equipment life, and improving operational safety. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a Z-axis moving mechanism.

[0019] Figure 2 This is a schematic diagram of the back structure of the fixed seat and the moving seat in a Z-axis moving mechanism.

[0020] Figure 3 This is a schematic diagram of the drive component in a Z-axis moving mechanism.

[0021] Figure 4 This is a schematic diagram of the detection component in a Z-axis moving mechanism.

[0022] Figure 5 In a Z-axis moving mechanism Figure 1 Enlarged structural diagram of section A.

[0023] Explanation of reference numerals in the attached figures: 100-Fixed base; 101-Chassis; 102-Upright plate; 200 - Movable base; 201 - Horizontal plate; 202 - Vertical plate; 203 - Mounting slot; 301-Servo motor; 302-Meshing wheel; 303-Rack; 304-Reducer; 401-Limiting window; 402-Triggering component; 403-Position sensor; 404-Light shield; 405-First buffer pad; 406-Second buffer pad; 407-Limiting block; 501 - Grating ruler; 502 - Reading head; 601 - Linear guide rail; 602 - Slider. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Example

[0025] Please see Figures 1 to 4 This embodiment describes in detail the specific implementation of a Z-axis moving mechanism.

[0026] The fixed base 100 is the installation foundation of the entire mechanism, and it consists of a horizontally arranged chassis 101 and a vertically arranged upright plate 102. The chassis 101 and the upright plate 102 are preferably integrally formed, but they can also be fixed together by welding or bolting to ensure overall rigidity and stability.

[0027] The movable seat 200 is slidably connected to the upright plate 102 of the fixed seat 100 through a straight guide assembly, so that it can move smoothly along the Z-axis direction, that is, the vertical direction.

[0028] The drive assembly provides power for the movement of the movable seat 200. It includes a servo motor 301, a meshing wheel 302, and a rack 303. The servo motor 301 is bolted to the movable seat 200. The output shaft of the servo motor 301 is connected to the input end of a reducer 304, which is also fixed to the movable seat 200. The reducer 304 increases the output torque and reduces the rotational speed, improving control smoothness and accuracy. The meshing wheel 302 is fixedly mounted on the output shaft of the reducer 304. The rack 303 is fixedly mounted on the upright plate 102 of the fixed seat 100, ensuring its meshing connection with the meshing wheel 302. When the servo motor 301 receives a control signal and rotates, it drives the meshing wheel 302 to rotate via the reducer 304. Since the rack 303 is fixed, the rotation of the meshing wheel 302 will be converted into linear motion of the moving seat 200, which is equipped with the servo motor 301 and the meshing wheel 302, along the direction of the rack 303. The meshing wheel 302 includes meshing rollers and gears that can mesh with the rack 303.

[0029] The limiting system is used to limit the safe travel range of the movable seat 200 to prevent it from overtraveling and causing a collision. It includes an elongated limiting window 401 on the vertical plate 102 of the fixed seat 100. A trigger assembly 402 is bolted to the vertical plate 202 of the movable seat 200 and extends into the limiting window 401, allowing it to move with the movable seat 200 within the range of the limiting window 401. A position sensor 403 is fixedly installed near the upper and lower ends of the limiting window 401, respectively. The position sensor 403 is preferably a U-shaped photoelectric sensor, comprising a transmitter and a receiver, which are arranged opposite each other to form a sensing area.

[0030] The working principle of this utility model is as follows: The control system issues a command to start the servo motor 301, which drives the moving seat 200 to move along the Z-axis through the meshing transmission of the meshing wheel 302 and rack 303. When the moving seat 200 drives the trigger component 402 to approach its travel limit, such as the upper limit, the light-shielding plate 404 on the limit block 407 in the trigger component 402 will enter the U-shaped groove of the position sensor 403 above, blocking the infrared beam. After the sensor 403 detects the change in light signal, it immediately outputs a switch signal to the control system. After receiving this signal, the control system immediately issues a command to stop the servo motor 301 or decelerate and reverse it, thereby realizing electronic soft limit. If the electronic limit fails due to a malfunction and the moving seat 200 continues to move, the first buffer pad 405 on the top of the limit block 407 will contact the upper edge of the limit window 401. The elastic deformation of the first buffer pad 405 absorbs the impact energy, realizing mechanical hard limit and buffer, effectively protecting the mechanism. Meanwhile, the actual position of the movable seat 200 is detected in real time by the grating ruler 501 and the reading head 502 and fed back to the control system, forming a closed-loop control to ensure extremely high positioning accuracy. Example

[0031] In a preferred embodiment, please refer to Figure 4 The linear guide assembly includes two parallel linear guide rails 601 vertically fixed to the upright plate 102 of the fixed base 100. Each linear guide rail 601 is equipped with a slider 602. The upright plate 202 of the movable base 200 is fixedly connected to the outer wall of all sliders 602 by bolts. By adopting a double linear guide rail layout, the anti-overturning moment capability and motion stability of the movable base 200 are greatly improved, ensuring its motion accuracy under high-speed and heavy-load conditions. Example

[0032] Furthermore, such as Figure 2 and Figure 3 As shown, the movable base 200 preferably adopts an L-shaped structure, consisting of a horizontally arranged horizontal plate 201 and a vertically arranged vertical plate 202. The horizontal plate 201 and the vertical plate 202 can be integrally formed by precision casting, or they can be connected by bolts or welding after machining. The horizontal plate 201 is used to bear the external load. The vertical plate 202 is used to connect with the slider 602 of the linear guide assembly and the drive assembly. A countersunk mounting groove 203 is machined in the middle of the upper surface of the horizontal plate 201. The servo motor 301 and the reducer 304 are integrally housed and fixed in the mounting groove 203. This layout makes the center of gravity of the drive components closer to the center of the movable base 200, and the structure is very compact, reducing the moment of inertia and improving dynamic performance. Example

[0033] Please refer to this carefully. Figure 3In a more specific embodiment, the triggering component 402 includes a limiting block 407 fixedly mounted on the movable base 200 and extending into the limiting window 401. A light-shielding sheet 404 is fixedly mounted on the limiting block 407 by a slot or screw. The light-shielding sheet 404 is made of an opaque material. When the movable base 200 moves to a preset limit position, the light-shielding sheet 404 will precisely insert into the U-shaped sensing area of ​​the corresponding position sensor 403, achieving reliable light-shielding triggering.

[0034] Meanwhile, a first buffer pad 405 is fixedly installed on the top of the limiting block 407 by adhesive or screws. The first buffer pad 405 is preferably made of engineering materials with high elasticity and high damping coefficient, such as polyurethane or nitrile rubber. It is suitable for contacting the metal edge of the limiting window 401 when the electronic limit fails, and absorbs and dissipates the impact kinetic energy through its own compression deformation, thus playing an effective buffering and protective role.

[0035] In addition, the limiting system also includes a second buffer pad 406. The second buffer pad 406 is fixedly installed on the chassis 101 of the fixed seat 100 by bolts or adhesive, and is precisely located at the end of the downward path of the vertical plate 202 of the movable seat 200. When the movable seat 200 descends to the lowest point, the lower edge of its vertical plate 202 will contact the second buffer pad 406, forming a final safety buffer to prevent direct metal-to-metal collision between the chassis 101 and the movable seat 200, thereby limiting the travel of the movable seat 200 downwards. Example

[0036] In another preferred embodiment, such as Figure 5 As shown, this utility model also includes a position detection component. The position detection component includes a grating ruler 501 and a reading head 502. The grating ruler 501 is precisely vertically fixed to the inner side of the upright plate 102 of the fixed base 100 via its attached mounting base. The reading head 502 is fixed to the upright plate 202 of the movable base 200 via its mounting bracket, with its sensing surface maintaining a very small and constant gap relative to the ruler surface of the grating ruler 501. When the movable base 200 moves, the reading head 502 reads the grating scale on the grating ruler 501 in real time and converts the position information into an electrical signal to feed back to the control system. This system constitutes a direct position measurement system independent of the meshing wheel 302 and rack and pinion 303 transmission chain, realizing fully closed-loop control, real-time detection and compensation of transmission errors, thereby ensuring ultimate positioning accuracy.

[0037] Finally, it should be noted that: The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A Z-axis moving mechanism, characterized in that, include: A fixed base, the fixed base including a chassis and an upright plate connected to the chassis; A movable seat, wherein the movable seat and the fixed seat are slidably connected via a linear guide assembly; The drive assembly includes a servo motor, a meshing wheel, and a rack. The servo motor is mounted on the movable base, the meshing wheel is connected to the output end of the servo motor, and the rack is fixedly mounted on the upright plate of the fixed base and meshes with the meshing wheel.

2. The Z-axis moving mechanism according to claim 1, characterized in that, It also includes a limiting system, which includes a limiting window on the upright plate of the fixed base, at least two position sensors disposed on the upper and lower sides of the limiting window, and a triggering component fixedly disposed on the movable base and extending into the limiting window to control the position sensors. The triggering component includes a limiting block fixedly installed on the movable base and extending into the limiting window, and a light-shielding plate disposed on the limiting block. When the movable base moves to a preset limit position, the light-shielding plate is adapted to enter the sensing area of ​​the corresponding position sensor to trigger a signal. The top of the limiting block is provided with a first buffer pad, which is adapted to contact the upper edge of the limiting window.

3. The Z-axis moving mechanism according to claim 2, characterized in that, The limiting system also includes a second buffer pad, which is disposed on the chassis of the fixed seat and located at the lower end of the moving path of the movable seat.

4. The Z-axis moving mechanism according to claim 1, characterized in that, The linear guide assembly includes at least one linear guide rail fixedly mounted on the upright plate, and a slider slidably disposed on the linear guide rail and fixedly connected to the movable seat.

5. A Z-axis moving mechanism according to claim 4, characterized in that, The number of linear guide rails is two, and the two linear guide rails are arranged parallel to each other on the upright plate.

6. The Z-axis moving mechanism according to claim 1, characterized in that, The movable seat includes a first part and a second part connected to each other. The first part is used to carry the load, and the second part is connected to the linear guide assembly and the drive assembly.

7. A Z-axis moving mechanism according to claim 6, characterized in that, The movable seat is L-shaped, with the first part being a horizontal plate and the second part being a vertical plate, the horizontal plate being connected to one end of the vertical plate.

8. A Z-axis moving mechanism according to claim 7, characterized in that, The horizontal plate is provided with a mounting groove, the servo motor is housed in the mounting groove, and is connected to the meshing wheel through a reducer.

9. A Z-axis moving mechanism according to claim 1, characterized in that, It also includes a position detection component, which includes a grating ruler disposed on the fixed base and a reading head disposed on the movable base and disposed opposite to the grating ruler.

10. A Z-axis moving mechanism according to claim 9, characterized in that, The grating ruler is vertically fixed to the upright plate, and the reading head is fixed to the movable base.

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