EP1834016B1

EP1834016B1 - Method for joining portions of knitting produced by at least two mutually spaced groups of needles of a bed, in circular hosiery knitting machines with two beds or the like

Info

Publication number: EP1834016B1
Application number: EP05804992A
Authority: EP
Inventors: Tiberio Lonati; Fausto Lonati; Ettore Lonati
Original assignee: Santoni SpA
Current assignee: Santoni SpA
Priority date: 2004-12-23
Filing date: 2005-12-12
Publication date: 2009-10-28
Anticipated expiration: 2025-12-12
Also published as: CN101080523B; CN101080523A; TW200639286A; WO2006066749A2; WO2006066749A3; EP1834016A2; DE602005017427D1; ITMI20042497A1

Description

Technical Field

The present invention relates to a method for joining portions of knitting produced by at least two mutually spaced groups of needles of a bed in circular hosiery knitting machines with two beds or the like, in which the two beds are coaxial and face each other. The method according to the invention can be used in particular to join portions of knitting produced by at least two groups of needles arranged in two sectors of a same bed, constituted for example by the needle cylinder of a cylinder-and-dial machine, which are mutually angularly spaced around the axis of the bed, on the same machine used to produce them.

Background Art

Circular hosiery knitting machines are known which have two coaxial and mutually facing beds, constituted for example by a needle cylinder, which has a vertical axis, and by a dial, which is arranged above and coaxially with respect to the needle cylinder.
A plurality of axial slots are provided on the lateral surface of the needle cylinder, and each slot accommodates a needle which can be actuated with a reciprocating motion along the corresponding axial slots in order to produce knitting.
In the dial of these machines there is a plurality of radial slots, each whereof accommodates at least one engagement element, which can be constituted by a hook or by a pusher or by a needle, which can move on command along the corresponding radial slot in order to pass from an extracted position, in which it protrudes from the peripheral profile of the dial, to a retracted position, in which it is recessed within the dial in order to avoid interfering with the needles of the needle cylinder.
In the extracted position, the engagement elements can interact with at least one needle of the needle cylinder in order to engage a loop of knitting or more generally a portion of a row of knitting produced by the needles of the needle cylinder or in order to release a loop of knitting or a portion of a row of knitting, engaged previously, to a needle of the needle cylinder.
In the retracted position, the engagement elements can retain the loop of knitting or portion of row engaged previously without interfering with the needles of the needle cylinder.
Depending on the type of engagement elements used, the engagement elements can pick up loops of knitting, in the strict sense of the term, from the needles that have produced them or can retain portions of loop linking yarn during the formation of a row of knitting by the needles of the needle cylinder and then release to the needles of the needle cylinder the loops of knitting previously picked up or the portions of loop linking yarn previously retained. For the sake of simplicity in presentation, the expression "loop of knitting" is understood hereinafter to designate a portion of a row of knitting which can be constituted by a loop of knitting in the strict sense of the term or by a portion of loop linking yarn.
In some machines, each engagement element is constituted by two or more elements arranged side-by-side, which are generally arranged in a same radial slot of the dial and cooperate with each other and with the needles of the needle cylinder in order to pick up loops of knitting from the needles of the needle cylinder or release to the needle of the needle cylinder loops of knitting previously picked up by other needles of the needle cylinder or retained during the formation of a row of knitting on the part of the needles of the needle cylinder.
If the engagement elements arranged in the dial are constituted by needles, said needles, in addition to being usable to engage or pick up loops of knitting produced by the needles of the needle cylinder, can also be used to produce knitting.
In the field of the production of items of clothing known as "seamless", i.e., items of clothing which have a tubular structure without seams at their lateral regions, the need is felt to be able to join portions of knitting, produced by groups of needles which are arranged in the needle cylinder and are mutually angularly spaced around the axis of the needle cylinder, so as to avoid the need to subsequently rework the item of clothing in order to produce the seam for joining said portions of knitting.
A need of this kind occurs for example for the shoulder straps of vests, bras, body suits or for the crotch of underpants.

Disclosure of the Invention

The aim of the present invention is to meet this need by providing a method which allows to join, directly on the machine used to produce an article, portions of knitting of the article produced by at least two groups of needles located in two sectors of a bed which are angularly mutually spaced around the axis of the bed, in circular hosiery knitting machines with two beds or the like.
Within this aim, an object of the invention is to provide a method which allows to reduce the production costs of said items of clothing by avoiding the sewing operation for joining portions of knitting.
Another object of the invention is to provide a method which allows to produce more comfortable items of clothing by avoiding the use of stitched seams to join portions of items of clothing.
This aim and these and other objects which will become better apparent hereinafter are achieved by a method for joining portions of knitting produced by at least two mutually spaced groups of needles of a bed in circular hosiery knitting machines with two beds or the like, which comprise two coaxial and mutually facing beds, respectively a first bed provided with needles which can be actuated to produce knitting and a second bed provided with engagement elements which can be actuated in order to retain or pick up loops of knitting formed by the needles of the first bed or release loops of knitting, retained or picked up previously, to the needles of the first bed, characterized in that it comprises:

a step for producing, by means of a first group of needles arranged in a first sector of the first bed, at least one first portion of knitting composed of a plurality of rows of knitting;
a step for producing, with a second group of needles arranged in a second sector of the first bed which is angularly spaced from said first sector of the first bed around the axis of the first bed, at least one second portion of knitting composed of a pluarality of rows of knitting;
a step for transferring at least one row of knitting of the first portion of knitting to at least part of the needles of said second group of needles, said transfer step being performed by means of said engagement elements of the second bed and by means of an angular offset of the second bed with respect to the first bed around its axis;
a step for producing at least one joining row of knitting by means of the needles of said second group of needles which engage said first portion of knitting which joins said first portion of knitting to said second portion of knitting.

The method according to the invention is meant to be performed preferably with a circular hosiery knitting machine of the type which comprises a needle cylinder which has a vertical axis and a dial which is arranged above and coaxially with respect to the needle cylinder and is provided with engagement elements which can be actuated in order to retain or pick up loops of knitting formed by the needles of the needle cylinder. If said engagement elements are constituted by hooks or pushers, i.e., elements which are not capable of forming knitting, the expression "first bed" is to be referred exclusively to the needle cylinder and the expression "second bed" is to be referred exclusively to the dial. If instead the engagement elements of the dial are constituted by needles, i.e., elements which can be actuated in order to form knitting, the expression "first bed" can be referred again to the needle cylinder and the expression "second bed" can be referred again to the dial or, equally, the expression "first bed" can be referred to the dial and the expression "second bed" can be referred to the needle cylinder. In this last case, the needles of the needle cylinder constitute the engagement elements of the second bed.
Without altering what has been specified above, for the sake of simplicity in description and greater clarity, the method according to the invention is described hereinafter by assuming that the "first bed" is the needle cylinder and the "second bed" is the dial of a circular hosiery knitting machine of the type with a needle cylinder and a dial.

Brief Description of the Drawings

Further characteristics and advantages of the invention will become better apparent from the description of two preferred but not exclusive embodiments of the method according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figures 1 to 4 are schematic views of a first embodiment of the method according to the invention in the production of a knitted article;
Figures 5 to 8 are schematic views of a second embodiment of the method according to the invention in the production of a knitted article;
Figure 9 is a view of a method for the engagement of a row of knitting of the first portion of knitting on the part of the engagement elements of the dial;
Figures 10 to 16 are views of a preferred method for transferring the row of knitting of the first portion of knitting from the engagement elements of the dial to the needles of the second group of needles.

Ways of carrying out the Invention

The method according to the invention is meant to be performed preferably with a circular hosiery knitting machine provided with a needle cylinder 1, which has a vertical axis 1a, and with a dial 4, which faces upwardly and coaxially the needle cylinder 1; said needle cylinder and said dial can each be actuated by means of a corresponding electric motor, with the possibility to manage electronically the way in which the two electric motors are actuated so as to turn, in some steps of the operation of the machine, the dial 4 rigidly or jointly with respect to the needle cylinder 1 about the common axis 1a and turn, in other steps of the operation of the machine, the dial 4 with respect to the needle cylinder 1 through angles which can vary according to the different operating requirements.
The dial 4 of the machine is provided with engagement elements, which can be actuated in order to engage loops of knitting 60 of a row of knitting produced by the needles of the needle cylinder 1 or in order to release loops of knitting 60, previously engaged, to needles of the needle cylinder 1.
Each engagement element can be constituted, in a per se known manner, by a needle or by at least one pusher or by at least one hook.
Depending on the type of machine and on the operating requirements, if the engagement elements are constituted by pushers or hooks, each engagement element can comprise two or more elements arranged side-by-side, which cooperate with each other in order to engage a loop of knitting 60 to be transferred and then transfer it to a needle of the needle cylinder 1.
More particularly, in the dial 4 there are is a plurality of radial slots, which are omitted in the figures for the sake of simplicity and inside each whereof there is an engagement element, which can move on command along the corresponding radial slot in order to pass from an extracted position, in which it protrudes from the peripheral profile of the dial 4 in order to interact with at least one needle of the needle cylinder 1, engaging a loop of knitting 60 of a row of knitting formed by the needles of the needle cylinder 1 or releasing a loop of knitting 60 engaged previously to a needle of the needle cylinder 1, to a retracted position, in which it is retracted within the dial 4 so as to retain the loop of knitting 60 engaged previously and/or not interfere with the needles of the needle cylinder 1.
The movement of the engagement elements along the corresponding radial slots of the dial 4 in order to transfer them from the extracted position to the retracted position or vice versa is achieved by providing, in a per se known manner, the engagement elements with one or more heels which protrude upwardly from the dial 4 and can engage actuation cams, which face upwardly the dial 4 and with respect to which the dial 4 turns, like the needle cylinder 1, about its own axis la during the operation of the machine.
The dial 4, particularly when the engagement elements are constituted by needles, can be provided with selection devices which allow to select even individually which engagement elements must be moved from the retracted position to the extracted position or vice versa. One of these devices is disclosed for example in US Patent no. 6,014,875 by the same Applicant.
If the engagement elements are constituted by needles, as shown in Figures 9 to 16, said needles have, in a per se known manner, a lateral spring 50, which forms, on the side of the shank of the needle, in a region which is spaced from the region where the needle latch acts, a slot 51, astride which it is possible to arrange the loop of knitting 60 that must be transferred and into which the tip of the needle of the needle cylinder 1 that must receive said loop of knitting 60 can be inserted. The needles of the needle cylinder 1, if they can release loops of knitting 60 to the needles of the dial 4, are provided likewise with a lateral spring 52, which defines, on the side of the shank of the needle, in a region which is spaced from the region where the latch of the needle acts, a slot 53, astride which it is possible to arrange the loop of knitting 60 that must be transferred and in which the tip of the needle of the dial 4 that must receive said loop of knitting 60 can be inserted.
The method according to the invention, in its most general embodiment, comprises a step for producing, with a first group of needles arranged in the first sector A of the needle cylinder 1, at least one first portion of knitting 2 which is composed of a plurality of rows of knitting and a step for producing, with a second group of needles arranged in a second sector B of the needle cylinder 1 which is angularly spaced from the first sector A around the axis 1a of the needle cylinder 1, at least one second portion of knitting 3 composed of a plurality of rows of knitting.
The method comprises a step for transferring at least one row of knitting of the first portion of knitting 2 to the needles of the second group of needles. This transfer step comprises a step for engaging, by means of the engagement elements of the dial 4, at least one row of knitting of the first portion of knitting 2, a step for the angular offset of the dial 4 with respect to the needle cylinder 1 around its axis 1a, and a step for releasing the row of knitting of the first portion of knitting 2, previously engaged by the engagement elements of the dial 4, from the engagement elements of the dial 4 to the needles of the second group of needles, arranged in the sector B of the needle cylinder 1.
After the transfer step, the method comprises a step for producing at least one row of knitting by means of the second group of needles arranged in the second sector B of the needle cylinder 1 and engaged with the first portion of knitting 2, so as to perform the seamless joining of the first portion of knitting 2 to the second portion of knitting 3, as will become better apparent hereinafter.
The step for producing the first portion of knitting 2 and the step for producing the second portion of knitting 3 can be performed simultaneously respectively by means of the first group of needles and by means of the second group of needles, as provided in the first embodiment of the method shown in Figures 1 to 4.
As an alternative, the step for producing the second portion of knitting 3 can be performed by the second group of needles after a row of knitting of the first portion of knitting 2 has been transferred onto them by means of the transfer step, as provided in the second embodiment of the method, shown in Figures 5 to 8.
The engagement step can be performed by picking up the final row of knitting produced by the needles of the first group of needles arranged in the sector A of the needle cylinder 1, by means of the engagement elements arranged in the dial 4, as provided in the first embodiment of the method. In this case, the first portion of knitting 2 is released from the needles of the first group of needles of the needle cylinder 1 to the engagement elements of the dial 4. One possible embodiment of this engagement method is shown in Figure 9, under the assumption of using needles as engagement elements, and with reference exclusively to three needles 41, 42, 43 which are arranged in a sector D of the dial 4 which pick up the loops of knitting from three needles 11, 12, 13 of the first sector A of the needle cylinder 1.
In this case, the needles 11, 12, 13, at the end of the formation of the first portion of knitting 2, are lifted towards the dial 4, so as to arrange the last loop of knitting 60 formed by each needle at the slot 53 formed on their side by the corresponding lateral spring 52 and arrange said slot 53 in alignment with the corresponding needle of the dial 4 that must pick up the loop of knitting 60. The needles of the dial 4 that were previously in the retracted position are then moved to the extracted position, so as to enter the slot 53 of the corresponding needle of the needle cylinder 1, which is then lowered so as to leave the loop of knitting 60 on the needle of the dial 4.
As an alternative, the engagement step can also be performed at the beginning of the formation of the first portion of knitting 2 knitted by the first group of needles of the needle cylinder 1, as provided in the second embodiment of the method, or in an intermediate step of the formation of the portion of knitting 2. In this case, the engagement elements of the dial 4, during the formation of the first row of knitting or of an intermediate row of knitting of the first portion of knitting 2, are moved into the extracted position, so that the yarn fed to the needles of the first group of needles of the needle cylinder 1 is engaged also by the engagement elements of the dial 4, which are then returned to the retracted position so as to retain the previously engaged yarn while the needles of the first group of needles of the needle cylinder 1 continue with the formation of the first portion of knitting 2.
Depending on the requirements, during the transfer of the row of knitting of the first portion of knitting 2 to the needles of the second group of needles it is possible to maintain or reverse the orientation of said row of knitting.
More particularly, if one wishes to maintain the orientation of the row of knitting of the first portion 2, after picking it up from the first group of needles, as explained with the aid of Figure 9, or after engaging the first row of knitting or an intermediate row of knitting by means of the engagement elements arranged in a sector D of the dial 4, the sector D of the dial 4 is made to face, by means of the offset of the dial 4 with respect to the needle cylinder 1, the sector B of the needle cylinder 1 in which the needles of the second group of needles are arranged, and then the loops of knitting pass from the engagement elements of the dial 4 to the needles of the second group of needles. This passage is performed without increasing or decreasing the offset of the dial 4 with respect to the needle cylinder 1 performed previously in order to make the sector D of the dial 4 face the second sector B of the needle cylinder 1.
If instead one wishes to reverse the orientation of the row of knitting of the first portion 2 during transfer, the transfer is performed by beginning the release of the row of knitting from the engagement elements arranged in the sector D of the dial 4 after the two angularly mutually closest or furthest ends of the sector D of the dial 4 and of the second sector B of the needle cylinder 1 have been made to face each other, and by releasing the row of knitting by means of the passage, in each instance, of a loop of knitting from the dial 4 to a needle of the second group of needles, gradually increasing or decreasing, between the passage of one loop of knitting and passage of a contiguous loop of knitting, the angular offset of the dial 4 with respect to the needle cylinder 1 about its axis 1a, until the transfer of the row of knitting from the dial 4 to the needles of the second group of needles is completed, as will be described in detail hereinafter.
This transfer technique is shown in Figures 10 to 16, under the assumption of using needles as engagement elements, and exclusively as regards three needles 41, 42, 43 arranged in a sector D of the dial 4, which must release the loops of knitting, engaged previously, to three needles 14, 15, 16 of the second sector B of the needle cylinder 1. With reference to said figures, after making the mutually closest ends of the sector D and of the sector B face each other by means of the offset of the dial 4 with respect to the needle cylinder 1, the loop of knitting 60 is released from the needle 43 of the dial 4 to the needle 14 of the needle cylinder 1, as illustrated in Figures 11 to 13, and then the offset of the dial 4 with respect to the needle cylinder 1 is increased and the loop of knitting 60 is released from the needle 42 of the dial 4 to the needle 15 of the needle cylinder 1, as shown in Figure 14, and then the offset of the dial 4 with respect to the needle cylinder 1 is increased further and the loop of knitting 60 is released from the needle 41 of the dial 4 to the needle 16 of the needle cylinder 1, as shown in Figure 15.
The reversal of the orientation of the row of knitting of the first portion of knitting 2 in passing from the sector D of the dial 4 to the needles of the second group of needles might also be performed by beginning the release from the needle 41 of the dial 4 to the needle 16 of the needle cylinder 1 and ending with the release from the needle 43 of the dial 4 to the needle 14 of the needle cylinder 1, and the angular offset between the dial 4 and the needle cylinder 1 might be performed clockwise or counterclockwise.
The expression "the ends of the sectors" of the needle cylinder 1 and of the dial 4 respectively is used to designate the ends of the sectors that are occupied by needles involved in the transfer of the loops of knitting 60.
The release of the loops of knitting 60 from each needle of the dial 4 to the corresponding needle of the needle cylinder 1 is performed by moving the needle of the dial 4 to the extracted position so as to arrange, in each instance, the loop of knitting 60 to be released so that it straddles the slot 51 formed by the lateral spring 50 on the side of the needle of the dial 4 and align said slot 51 with the needle of the needle cylinder 1 that must receive the loop of knitting 60. The needle of the needle cylinder 1 is then inserted through the slot 51 and the needle of the dial 4 is then moved into the retracted position so as to leave the loop of knitting 60 on the needle of the needle cylinder 1, as shown in particular in Figures 11, 12 and 13.
The needles of the dial 4 that must release the loop of knitting 60, as well as the needles of the needle cylinder 1 that must receive the loop of knitting 60, are selected, by means of corresponding selection devices, of a known type as mentioned above, so as to perform in each instance the extraction of a needle of the dial 4 and then its retraction into the dial 4, as well as the lifting and then lowering of the needle of the needle cylinder 1 that must receive the loop of knitting 60, before increasing or decreasing the offset of the dial 4 with respect to the needle cylinder 1 and thus extract the contiguous needle of the dial 4. The movement for extracting and retracting the needles of the dial 4 and movement for lifting and lowering the needles of the needle cylinder 1 can be achieved by actuating the needle cylinder 1 and the dial 4 with a continuous rotary motion about their own axis 1a or by actuating them with an alternating rotary motion about said axis 1a with respect to the cam or cams of the dial 4 which actuate the extraction and retraction of the needles of the dial 4 and with respect to the cams that actuate the lifting and lowering of the needles of the needle cylinder 1.
It should be noted that the reversal of the orientation of the row of knitting of the first portion of knitting 2 can be performed, instead of during the step for releasing the row of knitting to the second group of needles, during the step for engaging said row of knitting if said engagement step consists of a release of the row of knitting from the needles of the first group of needles to the engagement elements of the dial 4. In this case, the passage of the row of knitting from the needles of the first group of needles to the engagement elements of the dial 4 begins after the two angularly mutually closest or furthest ends of the sector D of the dial 4 and of the first sector A of the needle cylinder 1 have been made to face each other, and by performing the passage, in each instance, of a loop of knitting from a needle of the sector A to an engagement element of the sector D of the dial 4, gradually increasing or decreasing, between the passage of a loop of knitting and the passage of a contiguous loop of knitting, the angular offset of the dial 4 with respect to the needle cylinder 1 around its own axis 1a until the row of knitting is completely transferred from the needles of the first group of needles to the engagement elements of the dial 4.
The actuation of the needles of the first group of needles that must release the row of knitting and the actuation of the engagement elements of the dial 4 that must receive the row of knitting can be performed in a manner similar to what has been described above with reference to the release of the row of knitting from the dial to the second group of needles.
By means of the reversal of the orientation of the row of knitting of the first portion of knitting 2 during its transfer, it is possible to compensate for the rotation that the portion of knitting 2 undergoes as a consequence of the offset of the dial 4 with respect to the needle cylinder 1 or increase this rotation in order to achieve a twisting of the portion of knitting 2 depending on the effect that is to be obtained on the item of clothing.
More particularly, the method according to the invention, in the first embodiment shown in Figures 1 to 4, comprises a step for producing, with a first group of needles arranged in a first sector A of the needle cylinder 1, a first portion of knitting 2 which is composed of a plurality rows of knitting and simultaneously a step for producing, with a second group of needles arranged in a second sector B of the needle cylinder 1, a second portion of knitting 3 composed of a plurality of rows of knitting, until the portions of knitting 2 and 3 are completed (Figure 1).
The last row of knitting of the first portion of knitting 2 is then picked up by the needles of the first group of needles by means of the engagement elements arranged in a sector D of the dial 4 which faces, or is made to face, the first sector A of the needle cylinder 1. In Figures 1 to 4, the reference signs A1 and A2 designate the ends of the sector A, the reference signs a1, a2 designate the corresponding ends of the last row of knitting formed by the needles of the first group of needles, the reference signs B1 and B2 designate the ends of the sector B, the reference signs b1 and b2 designate the corresponding ends of the last row of knitting formed by the needles of the second group of needles, and the reference signs D1, D2 designate the ends of the sector D of the dial 4. In practice, during this step the ends a1 and a2 of the row of knitting pass respectively from A1 to D1 and from A2 to D2 (Figure 2).
The dial 4 is then offset with respect to the needle cylinder 1 about the axis 1a, counterclockwise in the figures, so as to approach the sector B of the needle cylinder until it faces, with the end D2, the end B1 of the second sector B which lies closest (Figure 3). At this point, the row of knitting of the first portion of knitting 2 begins to be released, with reversal of orientation, from the engagement elements arranged in the sector D of the dial 4 to the needles of the second group of needles, gradually increasing the offset of the dial 4 with respect to the needle cylinder. In this manner, the end a2 of the row of knitting of the first portion of knitting 2 passes from D2 to B1 and the end a1 passes from D1 to B2 (Figure 4).
In this manner, the two portions of knitting 2, 3 face each other with their reverse side on the needles of the second sector B and can be joined without seams but simply by actuating the needles of the second group of needles so as to produce one or more joining rows of knitting with ladderproof or ladder-resistant structures.
In the second embodiment, shown in Figures 5 to 8, the method according to the invention comprises a step for producing, by means of a first group of needles arranged in a first sector A of the needle cylinder 1, a first portion of knitting 2 composed of a plurality of rows of knitting. At the beginning of the production of the first portion of knitting 2, an initial row is retained by the engagement elements arranged in a sector D of the dial 4, which faces, or is made to face, the first sector of the cylinder (Figure 5).
Figures 5 to 8 designate with a1', a2' the ends of the row of knitting retained by the engagement elements of the sector D of the dial 4, and designate with D1, D2 the ends of the sector D of the dial 4. In practice, the ends a1' and a2' of the row of knitting are arranged respectively at the end D1 and at the end D2 of the sector D (Figure 5).
The dial 4 is then offset with respect to the needle cylinder 1 around the axis 1a, counterclockwise in the Figures, so as to move toward the sector B of the needle cylinder until it faces, with the end D2, the closest end B1 of the second sector B (Figure 6). At this point, the row of knitting of the first portion of knitting 2 begins to be released, with orientation reversal, from the engagement elements arranged in the sector D of the dial 4 to the needles of the second group of needles, gradually increasing the offset of the dial 4 with respect to the needle cylinder 1. In this manner, the end a2' of the row of knitting of the first portion passes from D2 to B1 and the end a1' passes from D1 to B2 (Figure 7).
At this point, the needles of the second group of needles are actuated in order to produce the second portion of knitting 3, which is formed as an extension of the first portion of knitting 2 (Figure 8).
It should be noted that the needles arranged in the first sector A of the needle cylinder 1 can resume knitting in order to continue the production of the article together with the needles arranged in the second sector B of the needle cylinder 1.
These embodiments of the method according to the invention can be used, for example, in order to join seamlessly the two flaps of the crotch of articles such as underpants or the like.
It should be noted that the reversal of the orientation of the row of knitting of the first portion of knitting 2 during its transfer can be used to compensate for the torsion of the first portion of knitting 2 as a consequence of the offset of the dial 4 with respect to the needle cylinder 1, allowing the joining of the reverse side of the first portion 2 with the reverse side of the second portion 3 and thus achieving the correct joining of the two portions of knitting 2, 3.
The method according to the invention has been explained exclusively with reference to the joining of two portions of knitting, but it can be used to perform, directly on the production machine, the joining of multiple pairs of portions of knitting produced by the needles arranged in various sectors of the needle cylinder, for example in order to join straps of body suits or bras without seams.
Moreover, in the illustrated embodiments the method according to the invention has been explained under the assumption of seeking to eliminate the twisting of the portions of knitting that are joined, but the reversal of the orientation of the row of knitting of the first portion of knitting during its transfer can be used in order to increase this twisting if required for aesthetic purposes or other purposes.
For the sake of greater simplicity, the method according to the invention has been described under the assumption that the two rows of knitting of the two portions of knitting that are joined have the same extension, but the joining of the two portions of knitting might also be performed between two rows of knitting which have mutually different dimensions, involving in the joining only a part of the longest row of knitting.
In practice it has been found that the method according to the invention fully achieves the intended aim, since it allows to perform, directly on the circular hosiery knitting machine with two beds or the like used to produce an article, the joining of portions of knitting produced by groups of needles which are located in sectors of a bed which are mutually angularly spaced around the axis of the bed, thus avoiding subsequent sewing operations.
The method thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.
In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.

Claims

A method for joining portions of knitting produced by at least two mutually spaced groups of needles of a bed in circular hosiery knitting machines with two beds or the like, which comprise two coaxial and mutually facing beds, respectively a first bed (1) provided with needles (11,12,13,14,15,16) which can be actuated to produce knitting and a second bed (4) provided with engagement elements (41,42,43) which can be actuated in order to retain or pick up loops of knitting (60) formed by the needles of the first bed (1) or release loops of knitting (60), retained or picked up previously, to the needles of the first bed, characterized in that it comprises:
- a step for producing, by means of a first group of needles (11,12,13) arranged in a first sector (A) of the first bed (1), at least one first portion of knitting (2) composed of a plurality of rows of knitting;

- a step for producing, with a second group of needles (14,15,16) arranged in a second sector (B) of the first bed (1) which is angularly spaced from said first sector (A) of the first bed (1) around the axis (1a) of the first bed (1), at least one second portion of knitting composed of a plurality of rows of knitting;

- a step for transferring at least one row of knitting of the first portion of knitting (2) to at least part of the needles of said second group of needles, said transfer step being performed by way of said engagement elements of the second bed (4) and by way of an angular offset of the second bed (4) with respect to the first bed (1) around its axis (1a);

- a step for producing at least one joining row of knitting by means of the needles of said second group of needles which engage said first portion of knitting (2) which joins said first portion of knitting (2) to said second portion of knitting (3).
The method according to claim 1, characterized in that said transfer step comprises:
- a step for engaging, by means of the engagement elements (41,42,43) arranged in a sector (D) of the second bed (4) of the machine, a row of knitting formed by said first group of needles (11,12,13) arranged in said first sector (A) of the first bed (1);

- a step for the angular offset of the second bed (4) with respect to the first bed (1) around the axis (1a) of the first bed (1) in order to move said sector (D) of the second bed (4) so that it is closer to, or faces, said second sector (B) of the first bed (1);

- a step for releasing the row of knitting (60), engaged previously by said engagement elements (41,42,43), from the engagement elements arranged in said sector (D) of the second bed (4) to said second group of needles (14,15,16) arranged in said second sector (B) of the first bed (1).
The method according to claim 1, characterized in that said step for producing a first portion of knitting (2) and said step for producing a second portion of knitting (3) are performed simultaneously respectively by means of said first group of needles (11,12,13) and by means of said second group of needles.
The method according to one or more of the preceding claims, characterized in that said step for producing a second portion of knitting (3) is performed by said second group of needles (14,15,16) after said at least one row of knitting of the first portion of knitting (2) has been transferred onto at least part of them in said transfer step.
The method according to one or more of the preceding claims, characterized in that the row of knitting of the first portion of knitting (2) that is engaged by said engagement elements (41,42,43) and transferred to at least part of the needles of said second group of needles (14,15,16) is constituted by the first row of knitting formed by said first group of needles (11,12,13).
The method according to one or more of the preceding claims, characterized in that the row of knitting of the first portion of knitting (2) that is engaged by said engagement elements (41,42,43) and transferred to at least part of the needles of said second group of needles (14,15,16) is constituted by an intermediate row of knitting formed by said first group of needles (11,12,13).
The method according to one or more of the preceding claims, characterized in that the row of knitting of the first portion of knitting (2) that is engaged by said engagement elements (41,42,43) and transferred to at least part of the needles of said second group of needles (14,15,16) is constituted by the last row of knitting formed by said first group of needles (11,12,13).
The method according to one or more of the preceding claims, characterized in that a reversal of the orientation of the row of knitting of said first portion of knitting (2) that is transferred is performed during said transfer step.
The method according to claim 8, characterized in that said reversal of the orientation of the row of knitting is performed during the step for releasing said row of knitting of the first portion of knitting (2) from said engagement elements (41,42,43) of the second bed (4) to the needles of said second group of needles (14,15,16).
The method according to claim 9, characterized in that said release step begins after arranging the angularly mutually closest or furthest ends of said sector of the second bed (4) and of the second sector (B) of the first bed (1) so that they face each other, and is performed by way of the passage, in each instance, of a loop of knitting (60) from the second bed (4) to a needle of said second group of needles (14,15,16), gradually increasing or decreasing, between the passage of a loop of knitting and the passage of the contiguous loop of knitting, the angular offset of the second bed (4) with respect to the first bed (1) until the transfer of the row of knitting from the second bed (4) to the needles of said second group of needles (14,15,16) is completed.
The method according to one or more of the preceding claims, characterized in that said engagement step is performed by means of the passage of a row of knitting (60) from said first group of needles (11,12,13) to the engagement elements (41,42,43) arranged in said sector (D) of the second bed (4), said reversal of the orientation of the row of knitting being performed during said engagement step.
The method according to claim 11, characterized in that said engagement step begins after arranging the angularly mutually closest or furthest ends of said sector (D) of the second bed (4) and of the first sector (A) of the first bed (1) so that they face each other and is performed by means of the passage, in each instance, of a loop of knitting (60) from a needle of said first group of needles (11,12,13) to an engagement element (41,42,43) which is arranged in said sector (D) of the second bed (4), gradually increasing or decreasing, between the passage of a loop of knitting and the passage of the contiguous loop of knitting, the angular offset of the second bed (4) with respect to the first bed (1) until the transfer of the row of knitting (60) from said first group of needles (11,12,13) to the engagement elements (41,42,43) arranged in said sector (D) of the second bed (4) is completed.
The method according to claim 1, 2, 4, 5 and 10, wherein the first bed (1) in the needle cylinder and the second bed (4) in the dial of a circular hoisery knitting machine.
Use of a circular hosiery knitting machine comprising:
- a needle cylinder (1), which can be actuated with a rotary motion about its own axis (1a), which is arranged vertically;

- a dial (4), which is arranged above and coaxially with respect to the needle cylinder (1);

- knitting engagement elements (41,42,43), which are arranged in said dial (4) and can be actuated in order to retain or pick up loops of knitting (60) formed by the needles (11,12,13,14,15,16) of the needle cylinder (1) or release loops of knitting, previously retained or picked up, to the needles of the needle cylinder;

- a first electric motor (M1) for actuating the needle cylinder (1) with a rotary motion about its axis (1a);

- a second electric motor (M2) for actuating the dial (4) with a rotary motion about its axis;

- a system for the electronic control (ECS) of the actuation of said electric motors (M1,M2) for a jointly coupled actuation of said needle cylinder (1) and of said dial (4) with a rotary motion about the common axis (1a) or for angular offset of said dial (4) with respect to said needle cylinder (1) about the common axis (1a); for performing the method according to one or more of the preceding claims.