US 4,918,913 A · Method of, and device for, performing a start spinning operation for spinning of a yarn in a friction spinning apparatus

Abstract

For performing a start spinning operation in a friction spinning apparatus, upon starting or recommencing spinning of a yarn after yarn breakage, there are accomplished the following steps: fibers opened in a fiber sliver opening device are delivered by a fiber infeed duct to a rotating friction spinning drum and twisted into a twisted fiber structure or coil. When the coil has reached a substantially predeterminate diameter it is entrained by an air jet delivered by a blowing duct into a yarn entraining nozzle which deflects the coil and the yarn following the coil, before they reach the rotating yarn drawn-off rolls, axially of the yarn draw-off rolls, into a yarn guide duct. A suction device is located at the outlet of the yarn guide duct such that a negative pressure is produced therein for taking up the air from an injector part of the yarn entraining nozzle and the coil and the yarn following the coil and supplying such to the suction device. After the coil has passed by a non-continuous draw-off roll of the yarn draw-off rolls, the entraining air in the injector part and in the blowing duct is interrupted such that the yarn extracted by the suction nozzle is stretched and issues from the yarn guide duct through a slot therein and is guided between the yarn draw-off rolls. This yarn take-up by the yarn draw-off rolls accelerates the yarn to the operative yarn draw-off speed.

Claims24

Dependent claims

In a method of performing a start spinning operation entailing starting or recommencing spinning of a yarn in a friction spinning apparatus, wherein freely floating fibers are delivered in a fiber infeed duct to a friction spinning surface of friction spinning means of the friction spinning apparatus, the fibers are conveyed on the friction spinning surface to a yarn formation location at which there is produced a yarn, and the yarn is withdrawn by yarn draw-off means, the improvement comprising the steps of:

conveying fibers to the yarn formation location;
twisting the fibers at the yarn formation location so as to form a twisted fiber structure of substantially predeterminate size;
generating an air jet for bypassingly conveying the twisted fiber structure and a yarn formed subsequent thereto past the yarn draw-off means;
engaging the twisted fiber structure and the subsequent formed yarn by yarn take-up means disposed after the yarn draw-off means with respect to a predeterminate direction of movement of the yarn;
interrupting the air jet;
and
introducing the yarn into the yarn draw-off means.

4 more elements

A device for performing a start spinning operation entailing starting or recommencing spinning of a yarn in a friction spinning apparatus, wherein:

said friction spinning apparatus comprises:
first friction spinning means provided with a friction spinning surface;
said first friction spinning means defining a yarn formation location at which there is formed a twisted fiber structure;
means for delivering fibers to the friction spinning surface of the first friction spinning means;
the fibers being formed into the twisted fiber structure at the yarn formation location during the start spinning operation;
a pair of yarn draw-off rolls for withdrawing the twisted fiber structure in the form of a yarn in a yarn withdrawal direction;
at least one roll of said pair of yarn draw-off rolls comprising a non-continuous yarn draw-off roll;
a second friction spinning means arranged in close proximity but in non-contacting relationship with respect to the first friction spinning means;
said first and second friction spinning means forming therebetween a gap of substantially constant but predeterminate width;
said device for performing the start spinning operation comprising:
a blowing duct through which travels an air jet;
said blowing duct having an outlet and a predeterminate blowing direction for the air jet;
the outlet of said blowing duct being directed towards the yarn formation location and the blowing direction being oriented such that thrust of the air jet is divisible into two force components of different magnitudes defining a force component of larger magnitude and a force component of smaller magnitude;
the force component of larger magnitude being effective in the yarn withdrawal direction;
a yarn take-up means disposed after the pair of yarn draw-off rolls viewed in the yarn withdrawal direction;
and
a yarn guiding element provided between the first and second friction spinning means and the yarn draw-off rolls for enabling the twisted fiber structure and a portion of the air jet in the blowing duct to bypass the non-continuous yarn draw-off roll such that the twisted fiber structure and a subsequent yarn portion can be engaged by the yarn take-up means.

14 more elements

Dependencies are inferred from the claim text.

Method of, and device for, performing a start spinning operation for spinning of a yarn in a friction spinning apparatus

Life of this patent

Method of, and device for, performing a start spinning operation for spinning of a yarn in a friction spinning apparatus

Life of this patent

Abstract

Claims24