Speed control type inertial force counteracting exercise system and counteracting method thereof

Abstract

This invention discloses a speed-controlled inertial force cancellation system and its cancellation method, comprising a worktable mounted on a frame, a worktable drive unit, a movable compensation unit, and a control unit. The worktable drive unit drives the worktable to accelerate and decelerate along a preset trajectory. The movable compensation unit is a moving body independent of the worktable drive unit, with a constant mass, and moves in the opposite direction to the worktable's motion direction under the control of the control unit. The control unit calculates the velocity and acceleration of the movable compensation unit based on the worktable's mass, real-time velocity and acceleration, and the movable compensation unit's mass, and calculates the movable compensation unit's velocity and acceleration based on the law of conservation of momentum, thereby driving the movable compensation unit to generate a compensation force equal in magnitude and opposite in direction to the worktable's inertial force, thus suppressing vibration transmitted to the frame. This invention can effectively cancel the worktable's inertial force without increasing the mechanism's or the overall weight, thus suppressing frame vibration.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing equipment technology, and more specifically to a speed-controlled inertial force cancellation system and its cancellation method. Background Technology

[0002] In semiconductor manufacturing equipment (such as chip mounters and flip chip mounters), linear servo motors are often used to drive the worktable to achieve high-speed reciprocating motion. When the worktable moves in height and accelerates or decelerates, the change in momentum of the worktable itself generates a reaction force of equal magnitude and opposite direction, which is transmitted to the support frame that mounts the worktable. This causes the support frame to vibrate and sway, resulting in a decrease in positioning accuracy and mounting accuracy, which affects product yield and production stability.

[0003] To address the aforementioned issues, some solutions currently employ the method of making the stator of the linear servo motor movable to counteract inertia. However, these methods have the following drawbacks: 1) Stator displacement is directly affected by the mass, speed, and acceleration of the worktable; 2) If the inertia is suppressed by reducing the stator displacement, the weight of the stator needs to be increased, which leads to an increase in the overall weight of the system; 3) If the stator weight is to be reduced, the stator displacement needs to be increased, which requires the addition of mechanical limit devices, increasing complexity and space requirements.

[0004] Therefore, how to develop a system that suppresses platform vibration by counteracting the inertial force of the worktable without increasing the overall weight has become an urgent problem to be solved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a speed-controlled inertial force cancellation motion system and its cancellation method, which can effectively cancel the inertial force of the worktable without increasing the weight of the mechanism and the overall weight, and without adding mechanical limiters, thereby suppressing the vibration of the frame and improving the mounting accuracy.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The innovation of the speed control type inertial force cancellation motion system of the present invention is that it includes a worktable mounted on a frame, a worktable drive unit, a movable compensation unit and a control unit. The worktable drive unit is used to drive the worktable to accelerate and decelerate along a preset trajectory; The movable compensation unit is a moving body independent of the worktable drive unit. It has a constant mass and is electrically connected to the control unit. It moves in the opposite direction of the worktable movement under the control of the control unit. The control unit is based on the mass m of the workbench. t The real-time movement speed v of the worktable t The acceleration a of the worktablet And the mass m of the movable compensation unit c Furthermore, the velocity v of the movable compensation unit is calculated based on the law of conservation of momentum. c And the acceleration a of the movable compensation unit c This drives the movable compensation unit, and by outputting a drive signal with opposite polarity, the movable compensation unit generates a compensation force in an axisymmetric manner that is equal in magnitude and opposite in direction to the inertial force of the worktable, thereby suppressing the vibration transmitted to the frame.

[0007] Preferably, the worktable drive unit is a linear servo motor, whose stator is fixedly installed and does not participate in the compensation motion.

[0008] Preferably, the movable compensation unit is an independent counterweight, and its displacement is constrained by controlling its movement speed through a control unit, thereby achieving the goal of not relying on increasing the counterweight mass or mechanical limiting.

[0009] Preferably, the control unit needs to be based on relation a. c =-(m t / m c ) a t To control the acceleration a of the movable compensation unit c .

[0010] Preferably, the control unit needs to be based on the relation v c =-(m t / m c ) v t To control the speed v of the movable compensation unit c .

[0011] Preferably, the control unit needs to be based on the relation p c =-(m t / m c ) p t To control the displacement p of the movable compensation unit c , where p t This represents the real-time displacement of the worktable.

[0012] Preferably, the control unit adopts a feedforward + feedback composite control method, that is, firstly, the speed and acceleration of the movable compensation unit are pre-calculated according to the worktable position command, and the compensation command is output; then, the vibration signal is collected through the acceleration sensor to correct the compensation command to cancel the interference.

[0013] The present invention provides a method for canceling inertial force in a velocity-controlled inertial force cancellation motion system, the innovation of which lies in including the following steps: (1) First, obtain the mass m of the workbench. tAnd the mass m of the movable compensation unit c ; (2) Real-time acquisition of the real-time movement speed v of the workbench t And the acceleration a of the worktable t ; (3) According to relation a c =-(m t / m c ) a t and v c =-(m t / m c ) v t Calculate the acceleration a of the movable compensation unit. c And the speed v of the movable compensation unit c ; (4) The control unit calculates the acceleration a c and speed v c Output drive signals with opposite polarity, so that the movable compensation unit generates a compensation force in an axisymmetric manner that is equal in magnitude and opposite in direction to the inertial force of the worktable. When the worktable and the movable compensation unit are regarded as a closed system, the force transmitted from the system to the outside approaches zero, thereby suppressing the transmission of vibration to the frame. (5) The feedforward control pre-calculates the compensation command and superimposes the accelerometer feedback correction to achieve stable vibration suppression throughout the motion range.

[0014] The beneficial effects of this invention are: (1) Without increasing the weight of the mechanism and the whole, and without adding mechanical limiters, the present invention can effectively counteract the inertial force of the workbench movement, thereby suppressing the vibration of the frame and improving the mounting accuracy. (2) This invention eliminates the need for additional mechanical limiters, thus reducing system complexity and space requirements; (3) The present invention can achieve real-time inertial cancellation in the entire motion range, with stable vibration suppression effect. It is applicable to multi-axis and multi-unit equipment, has strong versatility, and significantly improves the mounting accuracy of semiconductor equipment. 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 velocity control type inertial force cancellation method according to the present invention.

[0017] Figure 2 This is a schematic diagram of a speed control type inertial force cancellation method according to the present invention. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below through specific embodiments.

[0019] The present invention discloses a speed-controlled inertial force cancellation motion system, comprising a worktable mounted on a frame, a worktable drive unit, a movable compensation unit, and a control unit; as shown below. Figure 1 , Figure 2 As shown, the worktable drive unit is used to drive the worktable to accelerate and decelerate along a preset trajectory; the movable compensation unit is a moving body independent of the worktable drive unit, with a constant mass, and is electrically connected to the control unit, and moves in the opposite direction of the worktable's movement under the control of the control unit; the control unit adjusts the movement according to the mass m of the worktable. t The real-time movement speed v of the worktable t The acceleration a of the worktable t And the mass m of the movable compensation unit c Furthermore, the velocity v of the movable compensation unit is calculated based on the law of conservation of momentum. c And the acceleration a of the movable compensation unit c This drives the movable compensation unit, and by outputting a drive signal with opposite polarity, the movable compensation unit generates a compensation force in an axisymmetric manner that is equal in magnitude and opposite in direction to the inertial force of the worktable, thereby suppressing the vibration transmitted to the frame.

[0020] The workbench drive unit is a linear servo motor with a fixed stator that does not participate in the compensation motion; the movable compensation unit is an independent counterweight, and its displacement is constrained by controlling its movement speed through the control unit, thereby achieving the goal of not relying on increasing the counterweight mass or mechanical limit.

[0021] The control unit of this invention needs to be based on relation a c =-(m t / m c ) a t To control the acceleration a of the movable compensation unit c .

[0022] The control unit of this invention needs to be based on the relation v c =-(m t / m c ) v t To control the speed v of the movable compensation unit c .

[0023] The control unit of this invention needs to be based on the relation pc =-(m t / m c ) p t To control the displacement p of the movable compensation unit c , where p t This represents the real-time displacement of the worktable.

[0024] The control unit of this invention adopts a feedforward + feedback composite control method, that is, firstly, the speed and acceleration of the movable compensation unit are pre-calculated according to the position command of the worktable, and the compensation command is output; then, the vibration signal is collected by the acceleration sensor to correct the compensation command to cancel the interference.

[0025] The present invention provides a method for canceling inertial force in a velocity-controlled inertial force cancellation motion system, such as... Figure 1 , Figure 2 As shown, it includes the following steps: (1) First, obtain the mass m of the workbench. t And the mass m of the movable compensation unit c .

[0026] (2) Real-time acquisition of the real-time movement speed v of the workbench t And the acceleration a of the worktable t .

[0027] (3) According to relation a c =-(m t / m c ) a t and v c =-(m t / m c ) v t Calculate the acceleration a of the movable compensation unit. c And the speed v of the movable compensation unit c .

[0028] (4) The control unit calculates the acceleration a c and speed v c Outputting drive signals with opposite polarity causes the movable compensation unit to generate a compensation force equal in magnitude and opposite in direction to the inertial force of the worktable in an axisymmetric manner. When the worktable and the movable compensation unit are considered as a closed system, the force transmitted from the system to the outside approaches zero, thereby suppressing the transmission of vibration to the frame.

[0029] (5) The feedforward control pre-calculates the compensation command and superimposes the accelerometer feedback correction to achieve stable vibration suppression throughout the motion range.

[0030] The beneficial effects of this invention are: (1) Without increasing the weight of the mechanism and the whole, and without adding mechanical limiters, the present invention can effectively counteract the inertial force of the workbench movement, thereby suppressing the vibration of the frame and improving the mounting accuracy. (2) This invention eliminates the need for additional mechanical limiters, thus reducing system complexity and space requirements; (3) The present invention can achieve real-time inertial cancellation in the entire motion range, with stable vibration suppression effect. It is applicable to multi-axis and multi-unit equipment, has strong versatility, and significantly improves the mounting accuracy of semiconductor equipment.

[0031] 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 velocity-controlled inertial force cancellation motion system, characterized in that: It includes a worktable mounted on a frame, a worktable drive unit, a movable compensation unit, and a control unit; The worktable drive unit is used to drive the worktable to accelerate and decelerate along a preset trajectory; The movable compensation unit is a moving body independent of the worktable drive unit. It has a constant mass and is electrically connected to the control unit. It moves in the opposite direction of the worktable movement under the control of the control unit. The control unit is based on the mass m of the workbench. t The real-time movement speed v of the worktable t The acceleration a of the worktable t And the mass m of the movable compensation unit c Furthermore, the velocity v of the movable compensation unit is calculated based on the law of conservation of momentum. c And the acceleration a of the movable compensation unit c This drives the movable compensation unit, and by outputting a drive signal with opposite polarity, the movable compensation unit generates a compensation force in an axisymmetric manner that is equal in magnitude and opposite in direction to the inertial force of the worktable, thereby suppressing the vibration transmitted to the frame.

2. The velocity control type inertial force cancellation motion system according to claim 1, characterized in that: The worktable drive unit is a linear servo motor, whose stator is fixedly installed and does not participate in the compensation motion.

3. The velocity-controlled inertial force cancellation motion system according to claim 2, characterized in that: The movable compensation unit is an independent counterweight, and its displacement is constrained by controlling its movement speed through the control unit, thereby achieving the goal of not relying on increasing the counterweight mass or mechanical limit.

4. The velocity control type inertial force cancellation motion system according to claim 1, characterized in that: The control unit needs to be based on relation a. c =-(m t / m c ) a t To control the acceleration a of the movable compensation unit c .

5. A velocity-controlled inertial force cancellation motion system according to claim 1, characterized in that: The control unit needs to be based on the relation v c =-(m t / m c ) v t To control the speed v of the movable compensation unit c .

6. A velocity-controlled inertial force cancellation motion system according to claim 1, characterized in that: The control unit needs to be based on the relation p. c =-(m t / m c ) p t To control the displacement p of the movable compensation unit c , where p t This represents the real-time displacement of the worktable.

7. A velocity-controlled inertial force cancellation motion system according to claim 1, characterized in that: The control unit adopts a feedforward + feedback composite control method, that is, it first pre-calculates the speed and acceleration of the movable compensation unit according to the worktable position command and outputs the compensation command; then it collects the vibration signal through the acceleration sensor and corrects the compensation command to cancel the interference.

8. A method for canceling inertial force in a velocity-controlled motion system according to any one of claims 1 to 7, characterized in that... Includes the following steps: (1) First, obtain the mass m of the workbench. t And the mass m of the movable compensation unit c ; (2) Real-time acquisition of the real-time movement speed v of the workbench t And the acceleration a of the worktable t ; (3) According to relation a c =-(m t / m c ) a t and v c =-(m t / m c ) v t Calculate the acceleration a of the movable compensation unit. c And the speed v of the movable compensation unit c ; (4) The control unit calculates the acceleration a c and speed v c Output drive signals with opposite polarity, so that the movable compensation unit generates a compensation force in an axisymmetric manner that is equal in magnitude and opposite in direction to the inertial force of the worktable. When the worktable and the movable compensation unit are regarded as a closed system, the force transmitted from the system to the outside approaches zero, thereby suppressing the transmission of vibration to the frame. (5) The feedforward control pre-calculates the compensation command and superimposes the accelerometer feedback correction to achieve stable vibration suppression throughout the motion range.

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