GB2037329A

GB2037329A - Circular Knitting Machines

Info

Publication number: GB2037329A
Application number: GB7916676A
Authority: GB
Original assignee: Macchine Tessili Circolari MATEC SpA
Current assignee: Macchine Tessili Circolari MATEC SpA
Priority date: 1978-12-18
Filing date: 1979-05-14
Publication date: 1980-07-09
Also published as: GB2037329B; CS242861B2; CS865079A2; DE2946145A1; FR2444737A1; FR2444737B1; JPS5593856A

Abstract

In a circular knitting machine, a tensioning device for the article being knitted comprises a frusto-conical wall along which the article moves and a pair of annular elements with a flexible rim which act alternately on the article to urge it along the wall. The elements are concentric and are driven with a reciprocating motion. Inside the inner annular element there is a conduit which extends upwards from the flexible rim of this element. In the conduit there is created a pneumatic suction flow to reverse the article axially about said rim in the opposite direction to the direction in which the article normally extends from the narrowest region of the frusto-conical wall. The conduit opens by way of a grid into a chamber fitted above the tensioning device and which can be connected to a source of suction during knitting, and alternately to a source of pressure for expelling the finished article downwards, the chamber walls being fixed whereas the conduit rotates together with the flexible annular elements to drive same. <IMAGE>

Description

SPECIFICATION Circular Knitting Machines This application relates to a device for combining with circular knitting machines for forming articles which have to be turned inside out, this generally being done during a stage subsequent to their formation. In particular, but not exclusively, the device is for combination with circular machines for socks, of the kind provided with a cup-type tensioning device. This device generally comprises at one end a cone frustum wall along which the article is fed, normally downwards, during its formation, and at the other end an annular element or pair of elements (cups) with flexible rim which act alternately on the article to urge it along said cone frustum wall, said elements being concentric and being driven with staggered reciprocating motion.In one known design, it has been suggested to dispose a conduit inside the annular element, or inside the more internal of the annular elements, this conduit extending upwards from the flexible rim of said element, and creating a pneumatic suction flow in said conduit so as to reverse the article axially around said rim in the opposite direction to the direction which the article normally extends starting from the narrowest region of the cone frustum wall. According to the invention, the conduit opens by way of a grid into a chamber fitted above the tensioning device, and arranged to be connected alternately to a source of suction and a source of pressure in order to suck in the article during its manufacture and to expel the finished article downwards.The chamber walls are fixed, whereas said conduit rotates together with the flexible annular rimmed tensioning element of the cup device. The grid can extend over a certain portion of said conduit.

The suction chamber can be combined with a valve which, alternately with the suction, can establish a pressure for blowing and pneumatically expelling the article when it is finished and separated from the machine.

The drawing shows one embodiment of the invention, in which; Figure 1 is a partial section through the assembly showing the cup device provided with the arrangement for turning inside out, according to the model; and Figure 2 is an operating diagram.

As shown on the accompanying drawing, the reference numeral 1 indicates a cone frustum wall inside the needle cylinder of a machine for producing a tubular article to be turned inside out.

This cone frustum wall 1 extends downwards in the form of a narrow portion 1 A, through which the article normally passes during production. The reference numerals 3 and 5 indicate two flexible annular elements, inner and outer respectively, the lower edge of each of which cooperates with the wall 1 for tensioning the article M as it is progressively manufactured, and which is made to slide along the wall 1. The two elements 3 and 5 are each driven with reciprocating motion, and the two movements are staggered one to the other. The drive is obtained by means of an annular axial cam 7, with which two tappets 9 and 10 cooperate for raising two coaxial elements 12 and 14 respectively, rigid with support members 1 6 and 1 8 respectively for the two annular elements 5 and 3.The tappets 9 and 10 cooperating with the track 7 are controlled by return springs 20 and 22 respectively.

The staggered reciprocating movement of the two flexible annular elements 3 and 5 causes the article to move along the wall 1, each flexible annular element acting while the other is raised, thus providing uniform tensioning of the article M.

The flexible annular element 3 is controlled by the inner element 14, which according to the model is tubular and replaces the inner rod, which need not be tubular, usually provided in conventional tensioning devices of this type. The tube 14 extends in the form of a portion 1 4A terminating in a grid part 14B, which opens into a chamber A bounded by a wall 24 fitted on to the fixed structure 26 of the tensioning device. At its top, the wall 24 is connected to a connector 28 for a flexible conduit 30 which leads to a valve 32.

This valve is a four-way type, with one discharge port 32A and connectors for two conduits 34, 36 leading to the suction side and delivery side respectively of a fan 38, to provide suction or blowing of gas (in particular air) in the chamber A.

During the formation of the article and its tensioning, the chamber is put under suction and thus a suction air flow is formed in the conduit 14 in the direction of the arrow f1, in order to reverse the article M about the rim of the flexible element 3, so that during its formation the article is turned inside out relative to the state which it would have assumed if it had continued to move along the extension 1 A of the wall 1. When the article is finished and has been detached, the position of the valve 32 is reversed so blowing air into the chamber A and thus expelling the finished article along the tube 1 4 in the direction opposite the arrow f1.

Claims

1. A cup tensioning device, comprising a substantially cone frustum wall (along which the article moves, normally downwards, during its formation) and either one or a pair of annular elements (cups) with a flexible rim, which act alternately on the article to urge it along said cone frustum wall, said elements being concentric and being driven with staggered reciprocating motion, inside the inner annular element there being provided a conduit which extends upwards from the flexible rim of said element, in said conduit there being created a pneumatic suction flow to reverse the article axially about said rim in the opposite direction to the direction in which the article normally extends from the narrowest region of the cone frustum wall, characterised in that said conduit opens by way of a grid into a chamber fitted above the tensioning device and which can be connected to a source of suction

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Circular Knitting Machines This application relates to a device for combining with circular knitting machines for forming articles which have to be turned inside out, this generally being done during a stage subsequent to their formation. In particular, but not exclusively, the device is for combination with circular machines for socks, of the kind provided with a cup-type tensioning device. This device generally comprises at one end a cone frustum wall along which the article is fed, normally downwards, during its formation, and at the other end an annular element or pair of elements (cups) with flexible rim which act alternately on the article to urge it along said cone frustum wall, said elements being concentric and being driven with staggered reciprocating motion.In one known design, it has been suggested to dispose a conduit inside the annular element, or inside the more internal of the annular elements, this conduit extending upwards from the flexible rim of said element, and creating a pneumatic suction flow in said conduit so as to reverse the article axially around said rim in the opposite direction to the direction which the article normally extends starting from the narrowest region of the cone frustum wall. According to the invention, the conduit opens by way of a grid into a chamber fitted above the tensioning device, and arranged to be connected alternately to a source of suction and a source of pressure in order to suck in the article during its manufacture and to expel the finished article downwards.The chamber walls are fixed, whereas said conduit rotates together with the flexible annular rimmed tensioning element of the cup device. The grid can extend over a certain portion of said conduit. The suction chamber can be combined with a valve which, alternately with the suction, can establish a pressure for blowing and pneumatically expelling the article when it is finished and separated from the machine. The drawing shows one embodiment of the invention, in which; Figure 1 is a partial section through the assembly showing the cup device provided with the arrangement for turning inside out, according to the model; and Figure 2 is an operating diagram. As shown on the accompanying drawing, the reference numeral 1 indicates a cone frustum wall inside the needle cylinder of a machine for producing a tubular article to be turned inside out. This cone frustum wall 1 extends downwards in the form of a narrow portion 1 A, through which the article normally passes during production. The reference numerals 3 and 5 indicate two flexible annular elements, inner and outer respectively, the lower edge of each of which cooperates with the wall 1 for tensioning the article M as it is progressively manufactured, and which is made to slide along the wall 1. The two elements 3 and 5 are each driven with reciprocating motion, and the two movements are staggered one to the other. The drive is obtained by means of an annular axial cam 7, with which two tappets 9 and 10 cooperate for raising two coaxial elements 12 and 14 respectively, rigid with support members 1 6 and 1 8 respectively for the two annular elements 5 and 3.The tappets 9 and 10 cooperating with the track 7 are controlled by return springs 20 and 22 respectively. The staggered reciprocating movement of the two flexible annular elements 3 and 5 causes the article to move along the wall 1, each flexible annular element acting while the other is raised, thus providing uniform tensioning of the article M. The flexible annular element 3 is controlled by the inner element 14, which according to the model is tubular and replaces the inner rod, which need not be tubular, usually provided in conventional tensioning devices of this type. The tube 14 extends in the form of a portion 1 4A terminating in a grid part 14B, which opens into a chamber A bounded by a wall 24 fitted on to the fixed structure 26 of the tensioning device. At its top, the wall 24 is connected to a connector 28 for a flexible conduit 30 which leads to a valve 32. This valve is a four-way type, with one discharge port 32A and connectors for two conduits 34, 36 leading to the suction side and delivery side respectively of a fan 38, to provide suction or blowing of gas (in particular air) in the chamber A. During the formation of the article and its tensioning, the chamber is put under suction and thus a suction air flow is formed in the conduit 14 in the direction of the arrow f1, in order to reverse the article M about the rim of the flexible element 3, so that during its formation the article is turned inside out relative to the state which it would have assumed if it had continued to move along the extension 1 A of the wall 1. When the article is finished and has been detached, the position of the valve 32 is reversed so blowing air into the chamber A and thus expelling the finished article along the tube 1 4 in the direction opposite the arrow f1. Claims

1. A cup tensioning device, comprising a substantially cone frustum wall (along which the article moves, normally downwards, during its formation) and either one or a pair of annular elements (cups) with a flexible rim, which act alternately on the article to urge it along said cone frustum wall, said elements being concentric and being driven with staggered reciprocating motion, inside the inner annular element there being provided a conduit which extends upwards from the flexible rim of said element, in said conduit there being created a pneumatic suction flow to reverse the article axially about said rim in the opposite direction to the direction in which the article normally extends from the narrowest region of the cone frustum wall, characterised in that said conduit opens by way of a grid into a chamber fitted above the tensioning device and which can be connected to a source of suction during manufacture, and alternately to a source of pressure for expelling the finished article downwards, the chamber walls being fixed whereas said conduit rotates together with the flexible annular rimmed tensioning element of the cup device, and can constitute its axial drive member.

2. A device as claimed in the preceding claim, characterised in that the grid extends inside the chamber over a certain portion of the conduit.

3. A device as claimed in the preceding claims, characterised in that the suction chamber is combined with a valve which, alternately with the suction, can establish a pressure for blowing and pneumatically expelling the finished article when detached from the machine.

4. A cup tensioning device combined with an internal pneumatic reversing arrangement for turning the knitted article inside out during its formation on a circular knitting machine, all as described and represented.