Compact Motorized Flow Rate Valve With Closed-Loop Gear Drive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flow rate adjustment valves in semiconductor manufacturing lines face challenges with compactness, as manual valves require significant operator effort and motor-operated valves increase apparatus volume due to external stepping motors or built-in rack and pinion systems.
Innovation Solution
A compact flow rate adjustment valve using a stepping servo motor with integrated encoder for precise closed-loop control, combined with a gear system to minimize size and maintain precision, allowing for efficient motor placement adjacent to the rotation member, enabling compact dimensions comparable to manual valves.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If a stepping motor is disposed externally to enable motor-operated flow rate adjustment, then automation is improved, but the apparatus volume increases
Solution Approach 1:
The stepping motor is nested within the valve body structure, with the motor housing integrated into the existing valve components. The motor is positioned inside the bonnet assembly, utilizing the internal space of the valve structure rather than requiring external mounting space.
Solution Approach 2:
The motor is oriented with its rotational axis perpendicular to the traditional direction, allowing compact integration. The drive mechanism uses a planetary gear system that reduces the radial space requirements while maintaining the motor's rotational output for operating the valve stem.
2Extent of automation
If a built-in rack and pinion system is used for motor operation, then automation is improved, but the volume required for the rack and pinion and vertical movement increases
Solution Approach 1:
The traditional rack and pinion linear motion mechanism is replaced with a planetary gear reduction system combined with a lead screw or direct-drive stem mechanism. This substitution reduces the space required for the drive mechanism while maintaining the ability to convert rotational motor motion into linear stem movement for valve operation.
Solution Approach 2:
The gear ratio of the planetary gear system is optimized to provide sufficient torque multiplication while minimizing the physical dimensions of the gear components. The lead screw pitch is selected to achieve the required stem travel distance with minimal rotational input from the motor, reducing the overall volume of the drive mechanism.
3Volume of stationary object
If manual valve type is used to maintain compactness, then apparatus volume is reduced, but operator effort and time required for adjustment increases
Solution Approach 1:
The valve system performs self-adjustment through the automated motor control system, eliminating the need for manual operator intervention. The control system can automatically adjust the flow rate based on process requirements, and the motor-operated mechanism self-regulates the valve position without requiring human physical effort or time.
4Volume of stationary object
If motor size is reduced to maintain compactness, then apparatus volume is reduced, but motor performance and precision may deteriorate
Solution Approach 1:
A planetary gear reduction system is introduced as an intermediary between the small stepping motor and the valve stem. This gear system multiplies the motor's rotational torque while reducing the speed, providing sufficient force for valve operation without requiring a larger motor. The encoder serves as another intermediary, providing precise position feedback to the control system to maintain positioning accuracy despite the reduced motor size.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution allows for precise and efficient flow rate adjustment with reduced space requirements, maintaining the compactness of manual valves while providing the benefits of motor-operated systems, including automated operation and monitoring capabilities.
Implementation Method 1
a motor configured to rotate the driving gear, and the motor is a stepping servo motor
Implementation Method 2
The stepping servo motor is a stepping motor in which an encoder is incorporated. The stepping servo motor is configured to rotate a rotary shaft of the motor every predetermined angle by switching current that is caused to flow through a motor coil depending on pulse signals transmitted from a controller. At the same time, with feedback on the present position and speed from the encoder, errors from the operation command pulses are corrected, whereby closed loop control is performed.
Implementation Method 3
the rotation device comprises a driven gear disposed at a part of the rotation member, a driving gear engaged with the driven gear, and a motor configured to rotate the driving gear
Implementation Method 4
a rotation member that is screwed on the vertically movable body is rotated, whereby the vertically movable body moves upward or downward
Data Source
AI summary
Provided is a flow rate adjustment valve of a motor-operated valve type, which overcomes the problems that flow rate adjustment valves of a manual valve type have, while making full use of compactness the manual valves have. The flow rate adjustment valve includes a rotation device that rotates a rotation member to cause a vertically movable body to move vertically. The rotation device includes: a driven gear disposed at an upper end portion of the rotation member; and a motor that rotates a driving gear engaged with the driven gear. The motor, which is a stepping servo motor, is disposed below the driving gear and has a rotary shaft extending upward. The driving gear is fixed to an upper end portion of the rotary shaft.