A momentum cancellation based vibration suppression motion system and method of suppression thereof

Abstract

This invention discloses a vibration suppression system and method based on momentum cancellation, comprising an XY worktable mounted on a platform, a movable compensation unit, a drive unit, and a control unit; the control unit is electrically connected to the drive unit, and the control unit acquires the acceleration 'a' of the XY worktable. t And based on the mass m of the XY worktable t With the mass m of the movable compensation unit c The ratio is used to calculate the acceleration 'a' of the movable compensation unit. c The drive unit operates based on acceleration a. c This invention drives the movable compensation unit, causing the sum of the inertial forces of the XY worktable and the movable compensation unit to approach zero, thereby suppressing vibrations transmitted to the platform. The invention features a simple structure and stable control, requiring no additional mechanical limits or increased overall weight. It achieves vibration suppression at the source by controlling the movement of the movable compensation unit through a closed-loop speed control system.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing equipment technology, and more specifically to a vibration suppression system and method based on momentum cancellation. Background Technology

[0002] In semiconductor manufacturing equipment (such as chip mounters and flip chip mounters), linear servo motors are often used to drive XY stages to achieve high-speed reciprocating motion. When the XY stage moves vertically and accelerates or decelerates, the momentum change of the XY stage itself generates a reaction force of equal magnitude and opposite direction, which is transmitted to the support frame of the XY stage, causing vibration and swaying of the support frame. This leads to a decrease in positioning accuracy and mounting accuracy, affecting product yield and production stability.

[0003] To address the aforementioned issues, some solutions currently involve mounting the stator of the linear servo motor on a guide rail, allowing it to move freely. When the mover generates inertia, the stator moves in the opposite direction, thus counteracting the inertia. However, this method has the following drawbacks: 1) The weight and speed of the mover affect the weight and movement of the stator, leading to uncontrollable stator movement; 2) To reduce stator movement and suppress its inertia, the stator's weight needs to be increased, which increases the overall system weight and reduces response speed; conversely, reducing weight requires increasing stator movement, necessitating the addition of mechanical limit devices.

[0004] In addition, some solutions use simple feedforward or simple feedback control, but they generally suffer from poor anti-interference ability, insufficient dynamic response, and large phase deviation, making it difficult to meet the requirements of high-precision equipment.

[0005] Therefore, how to develop a vibration suppression system with controllable displacement without increasing the overall weight has become an urgent problem to be solved. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a vibration suppression motion system and its suppression method based on momentum cancellation. The system has a simple structure and stable control. It does not require additional mechanical limiters or increased overall weight. The movement of the movable compensation unit can be controlled by velocity closed-loop control, thereby achieving vibration suppression from the source.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention provides a vibration suppression motion system based on momentum cancellation, the innovation of which is: it includes an XY worktable mounted on a frame, a movable compensation unit, a drive unit, and a control unit; The control unit is electrically connected to the drive unit, and the control unit acquires the acceleration a of the XY stage. tAnd based on the mass m of the XY worktable t With the mass m of the movable compensation unit c The ratio is used to calculate the acceleration 'a' of the movable compensation unit. c ; The drive unit is based on acceleration a c This drives the movable compensation unit, making the sum of the inertial forces of the XY worktable and the movable compensation unit approach zero, thereby suppressing the vibration transmitted to the frame.

[0008] Preferably, the movable compensation unit is the stator of the linear servo motor of the XY worktable, and its stator can move freely along the guide rail; the drive unit is an independent linear motor, and it drives and controls the movement of the stator to counteract the inertial force generated when the mover of the XY worktable moves.

[0009] Preferably, the movement of the stator is limited by controlling its speed, and the mass and movement of the stator and mover of the linear servo motor remain constant.

[0010] Preferably, for acceleration control, the velocity v of the movable compensation unit is... c With the speed v of the XY worktable t The relationship between them must satisfy v c =-(m t / m c ) v t .

[0011] Preferably, for acceleration control, the movement p of the movable compensation unit c The amount of movement p of the XY worktable t The relationship between them must satisfy p c =-(m t / m c ) p t .

[0012] Preferably, the control unit also integrates a feedback control unit, which includes an acceleration sensor for real-time detection of the actual acceleration of the XY stage or the movable compensation unit, and for deviation correction of the feedforward command to counteract external interference.

[0013] The present invention discloses a method for suppressing vibration in a motion system based on momentum cancellation, the innovation of which lies in including the following steps: (1) First, obtain the mass m of the XY worktable. t The mass m of the movable compensation unit c and the acceleration a of the XY worktable t ; (2) According to formula a c=-(m t / m c ) a t Calculate the acceleration a of the movable compensation unit. c ; (3) The drive unit is based on the acceleration a c This drives the movable compensation unit, causing it to generate a force equal in magnitude and opposite in direction to the inertial force of the XY worktable. When the XY worktable and the movable compensation unit are considered as a closed system, the system's momentum changes with time at a rate of zero, thereby making the force transmitted from the system to the outside approach zero, thus suppressing the transmission of vibration to the platform. (4) Acquire actual motion signals through an accelerometer and perform feedback correction to suppress interference.

[0014] The beneficial effects of this invention are: (1) The present invention has a simple structure and stable control. It does not require additional mechanical limiters or increased overall weight. The movement of the movable compensation unit can be controlled by speed closed loop, thereby achieving vibration suppression from the source. (2) The present invention ensures dynamic response and improves anti-interference capability through feedforward control, and can be widely applied to high-speed precision semiconductor equipment such as chip mounting machines and flip chip mounting machines. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a flowchart of a vibration suppression method based on momentum cancellation according to the present invention.

[0017] Figure 2 This is a schematic diagram of the drive signal matching method based on the accelerometer of the present invention.

[0018] Among them, 1-mover of linear servo motor; 2-stator of linear servo motor; 3-mover of independent linear motor; 4-accelerometer. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below through specific embodiments.

[0020] The present invention discloses a vibration suppression motion system based on momentum cancellation, comprising an XY worktable mounted on a frame, a movable compensation unit, a drive unit, and a control unit; as shown below. Figure 1, Figure 2 As shown, the control unit is electrically connected to the drive unit, and the control unit acquires the acceleration 'a' of the XY stage. t And based on the mass m of the XY worktable t With the mass m of the movable compensation unit c The ratio is used to calculate the acceleration 'a' of the movable compensation unit. c The drive unit operates based on acceleration a. c This drives the movable compensation unit, making the sum of the inertial forces of the XY worktable and the movable compensation unit approach zero, thereby suppressing the vibration transmitted to the frame.

[0021] The movable compensation unit of this invention is the stator of the linear servo motor of the XY worktable, and its stator can move freely along the guide rail; the drive unit is an independent linear motor, and it drives and controls the movement of the stator to counteract the inertial force generated when the mover of the XY worktable moves.

[0022] The movement of the stator is limited by controlling its speed, and the mass and movement of the stator and mover of the linear servo motor remain constant.

[0023] This invention relates to acceleration control, specifically the velocity v of the movable compensation unit. c With the speed v of the XY worktable t The relationship between them must satisfy v c =-(m t / m c ) v t .

[0024] This invention relates to acceleration control, specifically the movement p of the movable compensation unit. c The amount of movement p of the XY worktable t The relationship between them must satisfy p c =-(m t / m c ) p t .

[0025] The control unit of the present invention also integrates a feedback control unit, which includes an acceleration sensor 4 for real-time detection of the actual acceleration of the XY stage or the movable compensation unit, and performs deviation correction on the feedforward command to counteract external interference.

[0026] The present invention provides a method for suppressing vibrations in a motion system based on momentum cancellation, such as... Figure 1 , Figure 2 As shown, it includes the following steps: (1) First, obtain the mass m of the XY worktable. t The mass m of the movable compensation unit cand the acceleration a of the XY worktable t ; (2) According to formula a c =-(m t / m c ) a t Calculate the acceleration a of the movable compensation unit. c ; (3) The drive unit is based on the acceleration a c This drives the movable compensation unit, causing it to generate a force equal in magnitude and opposite in direction to the inertial force of the XY worktable. When the XY worktable and the movable compensation unit are considered as a closed system, the system's momentum changes with time at a rate of zero, thereby making the force transmitted from the system to the outside approach zero, thus suppressing the transmission of vibration to the platform. (4) The actual motion signal is collected by the accelerometer 4 and feedback correction is performed to suppress interference.

[0027] The beneficial effects of this invention are: (1) The present invention has a simple structure and stable control. It does not require additional mechanical limiters or increased overall weight. The movement of the movable compensation unit can be controlled by speed closed loop, thereby achieving vibration suppression from the source. (2) The present invention ensures dynamic response and improves anti-interference capability through feedforward control, and can be widely applied to high-speed precision semiconductor equipment such as chip mounting machines and flip chip mounting machines.

[0028] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, all modifications and improvements made by those skilled in the art to the technical solutions of the present invention should fall within the protection scope of the present invention. The technical content for which protection is sought in the present invention has been fully described in the technical requirements.

Claims

1. A vibration suppression system based on momentum cancellation, characterized in that: It includes an XY worktable mounted on a frame, a movable compensation unit, a drive unit, and a control unit; The control unit is electrically connected to the drive unit, and the control unit acquires the acceleration a of the XY stage. t And based on the mass m of the XY worktable t With the mass m of the movable compensation unit c The ratio is used to calculate the acceleration 'a' of the movable compensation unit. c ; The drive unit is based on acceleration a c This drives the movable compensation unit, making the sum of the inertial forces of the XY worktable and the movable compensation unit approach zero, thereby suppressing the vibration transmitted to the frame.

2. The vibration suppression system based on momentum cancellation according to claim 1, characterized in that: The movable compensation unit is the stator of the linear servo motor of the XY worktable, and its stator can move freely along the guide rail; the drive unit is an independent linear motor, and it drives and controls the movement of the stator to counteract the inertial force generated when the mover of the XY worktable moves.

3. The vibration suppression system based on momentum cancellation according to claim 2, characterized in that: The amount of movement of the stator is limited by controlling its speed, and the mass and amount of movement of the stator and mover of the linear servo motor remain constant.

4. The vibration suppression system based on momentum cancellation according to claim 3, characterized in that: For acceleration control, the velocity v of the movable compensation unit c With the speed v of the XY worktable t The relationship between them must satisfy v c =-(m t / m c ) v t .

5. A vibration suppression system based on momentum cancellation according to claim 4, characterized in that: To perform acceleration control, the movement p of the movable compensation unit c The amount of movement p of the XY worktable t The relationship between them must satisfy p c =-(m t / m c ) p t .

6. A vibration suppression system based on momentum cancellation according to claim 5, characterized in that: The control unit also integrates a feedback control unit, which includes an acceleration sensor for real-time detection of the actual acceleration of the XY stage or movable compensation unit, and performs deviation correction on the feedforward command to counteract external interference.

7. The method for suppressing vibration in a motion suppression system based on momentum cancellation according to claim 6, characterized in that... Includes the following steps: (1) First, obtain the mass m of the XY worktable. t The mass m of the movable compensation unit c and the acceleration a of the XY worktable t ; (2) According to formula a c =-(m t / m c ) a t Calculate the acceleration a of the movable compensation unit. c ; (3) The drive unit is based on the acceleration a c This drives the movable compensation unit, causing it to generate a force equal in magnitude and opposite in direction to the inertial force of the XY worktable. When the XY worktable and the movable compensation unit are considered as a closed system, the system's momentum changes with time at a rate of zero, thereby making the force transmitted from the system to the outside approach zero, thus suppressing the transmission of vibration to the platform. (4) Acquire actual motion signals through an accelerometer and perform feedback correction to suppress interference.

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