Air Jet Loom Weft Insertion with Staged Auxiliary Nozzle Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In air jet looms, the configuration where the piping to the auxiliary main nozzle is shorter than the main nozzle leads to steep pressure rise, causing weft posture disorder, while longer piping results in residual pressure damage to the weft.
Innovation Solution
The weft insertion device employs a second valve device for the auxiliary main nozzle that transitions from a small flow rate to a steady flow rate during an initial jet period, and integrates the valve with the nozzle to minimize residual pressure damage and posture disorder.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the piping to the auxiliary main nozzle is made shorter, then residual pressure damage to the weft is reduced, but the pressure rise becomes too steep causing weft posture disorder
Solution Approach 1:
The patent applies parameter changes by making the piping length to the auxiliary main nozzle shorter than the main nozzle piping. This parameter modification reduces the residual pressure damage to the weft while the controlled pressure rise characteristics prevent weft posture disorder, resolving the technical contradiction between minimizing harmful residual pressure and maintaining weft insertion precision.
2Manufacturing precision
If the piping to the auxiliary main nozzle is made longer, then pressure rise becomes gentler preventing posture disorder, but residual pressure damage to the weft increases
Solution Approach 1:
The patent resolves this contradiction by changing the piping length parameter to be shorter for the auxiliary main nozzle. This shorter piping length reduces the time residual pressure acts on the weft, minimizing damage, while the design maintains appropriate pressure rise characteristics to prevent posture disorder.
3Stress or pressure
If the piping to the auxiliary main nozzle is made equal length with the main nozzle, then pressure rise characteristics are balanced, but residual pressure damage occurs due to longer residence time
Solution Approach 1:
The patent applies parameter changes by setting the auxiliary main nozzle piping length to be shorter than the main nozzle piping. This creates an asymmetric configuration that reduces residual pressure residence time, thereby minimizing damage to the weft while maintaining balanced pressure rise characteristics through other design parameters.
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 configuration reduces weft damage and posture disorder by gently increasing pressure, ensuring efficient and damage-free weft insertion.
Implementation Method 1
a second valve device which is capable of being in a state in which a flow rate smaller than a steady flow rate is supplied and a state in which the steady flow rate is supplied, and is put into the state in which the steady flow rate is supplied after the initial jet period
Implementation Method 2
a second main nozzle arranged upstream from the first main nozzle in a weft insertion direction and configured to function as an auxiliary main nozzle
Implementation Method 3
there is a merit that rising in pressure of compressed air jetted from the auxiliary main nozzle becomes gentler than that of the main nozzle
Implementation Method 4
even when the solenoid valve in the open state during the jet period is closed at a jet ending timing, the compressed air (residual pressure) remains in the piping to the main nozzle and the auxiliary main nozzle remains at that time
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A weft insertion device includes a first main nozzle and a second main nozzle that is arranged upstream from the first main nozzle in a weft insertion direction and is configured to function as an auxiliary main nozzle. The first main nozzle is connectable to a first valve device by a first piping. The second main nozzle is connectable to a second valve device by a second piping shorter than the first piping. The weft insertion device is configured to supply compressed air to each main nozzle with each valve device being in an open state over a jet period from a predetermined jet starting timing. In a predetermined initial jet period that begins at the jet starting timing, an operating state of the second valve device is put into a small flow rate state, in which a flow rate smaller than a steady flow rate is supplied.