Cap Seal Valve Sequencing for Ink Tank Refill
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Bubbler-style ink tanks for inkjet printers face issues with ink flow due to gravity, leading to ink drool or flooding at the print head assembly when the ink supply is above the print head, as breaking the seal to refill the tank results in loss of negative backpressure.
Innovation Solution
The sequencing of internal and external seals during ink refill operations, where a pre-loaded hinge automatically opens the cap assembly, actuating an internal valve seal before breaking the external seal between the bung and the ink tank, maintaining negative backpressure and preventing ink flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the external seal is broken to refill the ink tank, then the ink tank can be refilled, but negative backpressure is lost causing ink drool or flooding at the print head assembly
Solution Approach 1:
The internal valve seal is actuated to close before the external seal is broken during cap opening. The hinge mechanism is pre-loaded to automatically sequence the cap opening motion to first actuate the internal valve, establishing a seal before the external bung seal breaks, thus preventing ink flooding when refilling
Solution Approach 2:
The internal valve acts as an intermediary seal between the ink tank interior and the external environment. By closing this internal seal first, it mediates the transition from sealed to open state, preventing direct exposure of the ink supply to atmospheric pressure that would cause flooding
2Ease of operation
If the cap assembly is opened to refill the ink tank, then refilling can be performed, but ink flow due to gravity causes excessive ink flow when ink supply is above print head
Solution Approach 1:
The internal valve seal closes in advance before the external seal breaks during cap opening. This preliminary sealing action prevents gravity-driven ink flow from occurring when the cap is opened, as the internal valve maintains the seal until the external seal is already broken and refilling can begin
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
This solution ensures that the internal valve is sealed before the external seal is broken, preventing ink drool and flooding by maintaining negative backpressure, allowing for efficient and controlled refilling of the ink tank.
Implementation Method 1
a preloaded hinge between the cap housing and the ink tank. The hinge defines a rotational axis of the cap assembly when the cap assembly is opened and closed
Implementation Method 2
A spring is disposed between the cap housing and the bung. In the closed position, the spring applies a force to provide a seal between the bung and the ink tank
Implementation Method 3
maintaining negative backpressure, allowing for efficient and controlled refilling of the ink tank
Data Source
AI summary
An ink tank includes a cap assembly attached to the ink tank by a preloaded hinge that defines a rotational axis of the cap assembly when the cap assembly is opened and closed. The preloaded hinge biases the cap assembly to an opened position when the cap assembly is unlatched. The cap assembly includes a cap housing, a bung retained within the cap housing, a spring disposed between the cap housing and the bung, a latch to hold the cap assembly in a closed position, where in the closed position the spring applies a force to provide a seal between the bung and the ink tank. The cap assembly also includes an effector that is operative when the cap assembly is unlatched, to sequence a closing of an internal valve of the ink tank and a breaking of the seal between the bung and the ink tank thereafter.