Binary Pump Switching Valve for Backflow-Free Gradient Delivery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In gradient analyses using binary pumps, solvent backflow into inactive pump units occurs due to pressure increases, leading to delays in liquid delivery and poor mixing precision of the mobile phase, affecting separation and analysis reproducibility.

Innovation Solution

A switching valve configuration that allows independent connection of each pump unit to the output port, preventing backflow by switching between states without interrupting liquid delivery, and incorporating pressure sensors for pre-pressurizing operations to maintain system pressure balance, along with a leakage detection system to prevent liquid leakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a normal 6-way valve is used in a binary pump to connect pump units to the output port, then the valve can be switched between states to control liquid delivery, but backward flow of liquid to the inactive pump unit side cannot be prevented in gradient analysis starting from 0% first pump unit delivery

Engineering Contradiction:
Improvevalve switching capabilityVSAvoidliquid delivery accuracy
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The valve is segmented into multiple independent switching mechanisms (first switching mechanism for first pump unit, second switching mechanism for second pump unit) that can operate independently. This allows each pump unit to be connected or disconnected from the output port without affecting the other pump unit's connection state, enabling precise control over which pump units are active and preventing backward flow to inactive units.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The valve configuration is made dynamic by allowing independent switching of each pump unit's connection to the output port. The valve can adapt its connection state based on which pump units are currently active, switching between different configurations to prevent backward flow while maintaining continuous liquid delivery from active units.

Inventive Principle:
Principle #15Dynamics

2Ease of operation

If a normal 6-way valve is switched between states to connect different pump units to the output port, then liquid delivery can be controlled, but the connection between pump unit and output port is temporarily interrupted during switching

Engineering Contradiction:
Improvevalve switching flexibilityVSAvoidliquid delivery continuity
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The valve design ensures continuous liquid delivery by maintaining at least one active connection between a pump unit and the output port during switching operations. When switching between pump units or configurations, the valve transitions smoothly without creating a complete disconnection, ensuring that liquid flow to the output port remains continuous and uninterrupted.

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The valve structure acts as an intermediary that facilitates smooth transitions between different pump unit connections. By using a multi-position valve mechanism with intermediate states, the valve can redirect liquid flow through alternative paths during switching, preventing complete interruption of liquid delivery while reconfiguring the connection topology.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If the second pump unit is not connected to the output port while only the first pump unit is connected, then backward flow to the second pump unit can be prevented, but the valve cannot be set to a state where only the second pump unit is connected to the output port

Engineering Contradiction:
Improvebackward flow preventionVSAvoidvalve state configuration
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The valve system is divided into independent control segments for each pump unit, with separate switching mechanisms that can be controlled independently. This segmentation allows any combination of pump unit connections to the output port, including states where only the first pump unit is connected, only the second pump unit is connected, both are connected, or neither is connected, providing full adaptability for different gradient analysis requirements.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3517782B1Switching valve, binary pump, and liquid chromatograph with binary pump
Publication Date: 2024.06.12 SHIMADZU CORP
  • EP3517782B1 patent drawingFigure 1~2
  • EP3517782B1 patent drawingFigure 3~4
  • EP3517782B1 patent drawingFigure 5~6

AI summary

A switching valve is used in a binary pump. The switching valve is provided with a first liquid delivery port to which a first pump unit is connected, a second liquid delivery port to which a second pump unit is connected, and an output port leading to an output unit that outputs a liquid to be delivered. The switching valve is configured so as to be switched to any one of the following states: a first state in which the first liquid delivery port is connected to the output port and the second liquid delivery port is not connected to any port; a second state in which the second liquid delivery port is connected to the output port and the first liquid delivery port is not connected to any port; and a third state in which both the first liquid delivery port and the second liquid delivery port are connected to the output port.