Beam Limiting Unit Asymmetric Blade Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing beam limiting units in radiology struggle to precisely set the central ray of the X-ray beam to a desired position and require multiple actuators, making them time-consuming, unreliable, and costly to control.
Innovation Solution
A beam limiting unit with two actuators and separate force transmission chains allows for simultaneous movement of both blades, enabling quick adjustment of the aperture's width and symmetry axis, allowing the central ray to be positioned accurately and efficiently, even during X-ray emission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple actuators are used for each blade to enable independent positioning, then the central ray can be precisely set to any desired position, but the device complexity increases and the positioning time becomes longer
Solution Approach 1:
The patent divides the blade positioning control into two independent stages: first positioning the symmetry axis (central ray) using one actuator, then adjusting the aperture width using another actuator. This segmentation allows precise control of the central ray position without requiring multiple actuators for each blade, reducing device complexity while maintaining positioning precision.
Solution Approach 2:
The patent implements preliminary positioning of the symmetry axis before final aperture width adjustment. By first establishing the correct central ray position through symmetry axis alignment, and then making width adjustments that maintain this positioning, the system achieves precise central ray control without requiring continuous multi-actuator coordination, thereby reducing overall device complexity.
2Measurement precision
If multiple actuators are used for each blade to enable independent positioning, then each blade can be adjusted independently, but the positioning time increases and productivity decreases
Solution Approach 1:
The patent segments the positioning process into two rapid sequential stages: symmetry axis positioning followed by width adjustment. This segmentation allows each stage to be completed independently and quickly by dedicated actuators, achieving precise blade positioning without the time penalty of coordinated multi-actuator operation, thereby improving productivity.
Solution Approach 2:
The system performs preliminary symmetry axis positioning that establishes the correct central ray position before final width adjustment. This preliminary action ensures that subsequent width adjustments do not require repositioning the central ray, enabling rapid final positioning and improving overall productivity while maintaining precision.
3Reliability
If multiple actuators are used for each blade, then reliable independent control is achieved, but the cost and device complexity increase
Solution Approach 1:
The patent segments control functions into two independent control loops: symmetry axis control and width control. Each loop uses a single dedicated actuator, reducing the total number of actuators and device complexity while maintaining reliability through functional separation. The independent control loops prevent interference between positioning and adjustment operations.
Solution Approach 2:
The system establishes preliminary symmetry axis positioning that creates a stable foundation for subsequent width adjustments. This preliminary action ensures that width adjustment actuators operate without interfering with central ray positioning, maintaining control reliability while reducing the number of actuators needed for coordinated control.
4Shape
If symmetrical blade movement is used to define aperture width, then the aperture shape is maintained, but the central ray position cannot be adjusted
Solution Approach 1:
The patent segments aperture control into two independent functions: symmetry axis positioning (controlling central ray position) and width adjustment (controlling aperture dimensions). This segmentation allows the aperture shape to be maintained during width adjustment while enabling independent central ray positioning, resolving the contradiction between shape maintenance and position adjustability.
Solution Approach 2:
The system performs preliminary symmetry axis positioning to establish the correct central ray position before making width adjustments. This preliminary action ensures that subsequent width adjustments occur symmetrically around the correctly positioned central ray, maintaining aperture shape integrity while achieving precise central ray positioning.
Data Source
Figure 1
Figure 2A~2O
Figure 2B~2C
AI summary
A method and a unit(1) for limiting an X-ray beam on opposite sides of the X-ray beam is proposed. The unit (1) comprises: - two blades (5, 6) disposed on opposite sides of the X-ray beam and having inner edges, which delimit the X-ray beam on said opposite sides, and - an actuator (12) linked to both blades (5, 6) and moving both of them in an approaching direction reducing the space between the inner edges of the blades (5, 6), and in a withdrawing direction enlarging the space between the inner edges of the blades (5, 6), wherein - one of the blades (5) is linked to the actuator (12) through an uncoupling device system (9) which allows a relative movement of the one blade (5) with respect to a holder which supports the one blade (5) and is engaged with the actuator (12), and wherein - the motion of the one blade (5) in approaching direction and/or withdrawing direction is impedable causing an asymmetric motion of the blades with respect to an initial position of a symmetry axis of a space between the inner edges of the blades (5, 6)