Dynamic Occlusion Adjustment in Roller Pumps
Solution Overview
Problem
Conventional roller pumps require the pump to be stopped and manually adjusted for occlusion settings, which is time-consuming and cumbersome, especially in perfusion circuits where precise adjustments are needed while maintaining fluid flow.
Innovation Solution
A roller pump design with an occlusion adjustment assembly that allows for radial position adjustment of rollers relative to the stator surface while the pump is operating, using a motor-driven mechanism with a controller for automated adjustments based on perfusion circuit parameters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional occlusion adjustment mechanisms are used, then the pump can be adjusted for different tubing sizes and flow rates, but the pump must be stopped during adjustment which reduces productivity and increases loss of time
Solution Approach 1:
The occlusion adjustment mechanism is designed to be dynamically adjustable during pump operation. The roller position relative to the stator surface can be changed while the pump is running, allowing continuous adaptation of occlusion settings without stopping the pump, thus maintaining productivity while providing versatility.
Solution Approach 2:
The adjustment mechanism allows the pump to maintain continuous fluid pumping action while the occlusion setting is being modified. The roller can be repositioned radially during operation, ensuring that the useful action of pumping continues uninterrupted, eliminating idle time and maintaining productivity.
2Adaptability or versatility
If manual occlusion adjustment is performed, then the distance between rollers and raceway can be changed, but the process is cumbersome and inconsistent requiring manual measurement and stopping the pump
Solution Approach 1:
The manual mechanical adjustment process is replaced with an automated motor-driven mechanism. A motor rotates a cam structure that automatically translates rotational motion into radial displacement of the roller, eliminating the need for manual measurement and adjustment while providing consistent, repeatable occlusion settings.
Solution Approach 2:
The system provides self-service adjustment through automated control. The motor-driven cam mechanism automatically performs the adjustment function when actuated, reducing the operator's role from manually measuring and positioning to simply initiating the adjustment, thereby simplifying the operation.
3Measurement precision
If the pump is stopped for occlusion adjustment, then precise manual adjustment can be performed, but time is lost and pump operation is interrupted
Solution Approach 1:
The adjustment mechanism is designed to be pre-configured with cam profiles that correspond to desired occlusion settings. When adjustment is needed, the motor simply rotates the cam to the appropriate position, which has already been designed to provide the precise roller displacement needed, eliminating time-consuming manual measurement while maintaining precision.
Solution Approach 2:
The time-consuming manual adjustment process is replaced by an automated motor-driven system that can quickly and precisely reposition the roller. The motor can rapidly move the roller to the correct position without the delays associated with manual operation, significantly reducing adjustment time while maintaining precision through controlled actuation.
4Productivity
If automated motor-driven occlusion adjustment is implemented, then continuous pump operation is maintained, but device complexity increases
Solution Approach 1:
The automated adjustment mechanism is nested within the existing pump structure. The motor, cam structure, and roller mounting are integrated into the pump housing and rotor assembly, with the cam mechanism fitting within the rotor hub. This nesting approach minimizes the additional space and structural complexity required while enabling continuous operation.
Solution Approach 2:
The adjustment mechanism components (motor, cam, roller mounting) are merged with the existing pump structure. The cam structure is integrated with the rotor hub, and the roller is part of the rotor assembly, combining multiple functions into unified components rather than adding separate independent systems, thereby reducing overall complexity.
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
Enables continuous operation and precise occlusion adjustment without stopping the pump, improving efficiency and reducing user effort in perfusion circuits by allowing occlusion adjustments during fluid pumping.
Implementation Method 1
a motor, a rotor assembly, a stator housing, and an occlusion adjustment assembly. The drive shaft defines a central axis and is coupled to the motor. The motor thus rotates the drive shaft about the central axis.
Implementation Method 2
the roller(s) compress the tubing against the inner circumferential surface of the pump stator as it is rolled along the tubing. The fluid medium contained in the tubing is then transported in a direction of the pump rotor rotation.
Implementation Method 3
the pump rotor engages tubing positioned in the pump stator with one or more rollers. Upon rotation of the pump rotor by a rotating shaft, the roller(s) compress the tubing against the inner circumferential surface of the pump stator
Implementation Method 4
The occlusion adjustment assembly slidably adjusts a radial position of the roller relative to the receiving surface, and includes an actuator knob, an actuating structure, and a ground shaft disposed within the drive shaft. The actuating structure is connected to the knob. The ground shaft supports the actuator knob relative to the drive shaft. In this regard, the actuating structure interfaces with the slide body to selectively alter a radial position of the slide body relative to the central axis of the drive shaft with rotation of the knob.
Data Source
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AI summary
A roller pump including a drive shaft, a motor, a roller head assembly, a stator housing, and an occlusion adjustment assembly. The drive shaft is coupled to the motor. The roller head assembly includes a hub, a slide body, and a roller. The hub is mounted to the drive shaft, and maintains the slide body and the roller. The stator housing forms a raceway receiving surface. The occlusion adjustment assembly includes an actuator knob, an actuating structure, and a ground shaft. The actuating structure interfaces with the slide body, and thus the roller, with rotation of the knob. The ground shaft supports the knob and is rotationally isolated from the drive shaft. A user and optionally a control system can adjust occlusion while the pump continuously delivers a fluid medium.