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US 4,641,688 AGranted
Weft thread braking mechanism having a stepwise controllable braking effect
AssigneeLindauer Dornier Gesellschaft mbH
InventorFritz Gehring
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AssigneeLindauer Dornier Gesellschaft mbH
InventorFritz Gehring
Estimating the term…
A weft thread brake for shuttleless weaving machines includes two leaf springs or lamellae which rest against each other in a spring elastic manner. The thread, such as a weft thread, passes through a passage formed between the two leaf springs as the thread is being pulled off a supply reel or bobbin whereby the two leaf springs apply a braking action to the thread. In their basic position the leaf springs exert a first step of a defined braking action on the thread. Additionally, controllable members are arranged for cooperation with the leaf spring or springs to increase or decrease the pressure of the two leaf springs toward each other. Electromagnets, compression elements, or the like, are suitable for this purpose, whereby the actuation of these control members increase the braking action even to the extent of clamping the weft thread between the leaf springs if desired.
A weft thread brake for applying a stepwise controllable braking effect to a weft thread, comprising two leaf springs resting against each other and forming a funnel type passage for the respective weft thread, said two leaf springs having a normal biasing force for applying a first step in the braking effect individually to said weft thread, mounting means (1, 2, 3) for mounting said two leaf springs so that the position of at least one of said two leaf springs is changeable relative to the position of the other leaf spring, and individually controllable force application means operatively arranged for directly applying to said leaf springs a stepwise increase or decrease of a force directed substantially perpendicularly to said leaf springs, whereby said normal biasing force of said leaf springs is changed and the respective braking effect is individually controlled in a stepwise manner for said weft thread.
Dependencies are inferred from the claim text.