WO2008090573A1

WO2008090573A1 - Automatic multi -needle sewing machine for making ornamental stitches with chain stitch, to create ornamental effects with moss stitch and chenille stitch, for the application of tapes, and relative method

Info

Publication number: WO2008090573A1
Application number: PCT/IT2007/000050
Authority: WO
Inventors: Alberto Landoni
Original assignee: Alberto Landoni
Priority date: 2007-01-25
Filing date: 2007-01-25
Publication date: 2008-07-31
Also published as: EP2109696A1

Abstract

Automatic multi-needle sewing machine (10) and method for making continuous or isolated ornamental stitches with 4 or more colours with chain stitch and for creating ornamental effects with moss stitch and chenille stitch, on a fabric (11) fed continuously, from roll to roll. The sewing machine has upper sewing members (30) and lower sewing members (31), and at least a supporting bar (21) with which the upper sewing members are able to be associated. The upper sewing members (30) comprise a plurality of hook-type needles (41), mobile with a rotatory motion and an alternate vertical motion, and the lower sewing members (31) are solid with the base of the sewing machine (10) and comprise a plurality of lower thread feeders (63) able to feed said hook-type sewing needles (41) with sewing threads (56) of different colours.

Description

"AUTOMATIC MULTI-NEEDLE SEWING MACHINE FOR MAKING ORNAMENTAL STITCHES WITH CHAIN STITCH, TO CREATE ORNAMENTAL EFFECTS WITH MOSS STITCH AND CHENILLE STITCH, FOR THE

APPLICATION OF TAPES, AND RELATIVE METHOD" * * * * *

FIELD OF THE INVENTION

The present invention concerns a automatic multi-needle sewing machine for making continuous or isolated ornamental stitches with chain stitch with 4 or more different colors, for creating ornamental effects with moss stitch and chenille stitch and for the application of tapes with chain stitches on a fabric fed continuously, from roll to roll.

The invention also concerns a method for continuous or isolated sewing with chain stitch with 4 or more different colors, for creating ornamental effects with moss stitch and chenille stitch and for the application of tapes with chain stitches on said fabric.

Here and hereafter, the fabric is intended as the simple type, multi-layer or padded and always fed continuously from rolls.

BACKGROUND OF THE INVENTION

In the field of multiple-head sewing machines and embroidery machines it is known to make stitches with a chain stitch with different colors, to create moss/chenille effects and to apply tapes on fabrics cut into pieces 60 cm wide. Such operations are normally carried out with specific machines that require manual steps to reposition the fabrics, cut and manually fixed on frames with every production cycle, which causes a serious limit to the articles as the area sewn is limited to 60 cm, and entails a considerable expense and dispersion of energy, or with manual Cornelly sewing machines that perform stitches on finished garments. One purpose of the present invention is to achieve a sewing machine with chain stitch with 4 or more different colors for making continuous or isolated ornamental stitches, for creating ornamental effects with moss stitch and with chenille stitch and for applying tapes with chain stitches on a continuously fed fabric.

A further purpose is to perfect a relative sewing method that will allow to continuously work the fabric, obtaining any desired continuous or isolated ornamental pattern by means of chain stitches with 4 or more different colors, creations of ornamental effects with moss stitch and chenille stitch and applications of tapes with chain stitches.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages .

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, an automatic multi-needle sewing machine, and a method, according to the present invention can be used to achieve ornamental stitches, continuous or isolated, with chain stitch with 4 or more different colors, to create ornamental effects with moss stitch and chenille stitch, to apply tapes with chain stitches on a fabric fed continuously from roll to roll and with a working width of up to 3.5 meters.

The sewing machine according to the present invention comprises upper and lower sewing members cooperating with each other so as to achieve stitches on the fabric, and at least one supporting bar.

The upper sewing members are able to be associated with the supporting bar by means of attachment means, while the lower sewing members are solid with the base of the sewing machine .

According to a characteristic of the present invention, the upper sewing members comprise means to drive hook-type needles, and the lower sewing members comprise means to feed the sewing threads of various colors. When continuous or isolated ornamental stitches with chain stitch are made, the upper sewing members drive the sewing needles, of the hooked type, imparting to them two movements, an ascending-descending one of an amplitude such as to make them penetrate the fabric being treated, and an intermittent rotating one so as to maintain the open sides of the hooks always facing towards the sewing direction, which can change at any point according to the ornamental pattern to be made; the lower sewing members drive the feeders of the sewing threads of the particular color required by the ornamental pattern to be made, making them complete, at each stitching point, a full rotation in a clockwise direction with a starting position always in phase with the position of the hooks of the needles.

When ornamental patterns with moss stitch and chenille stitch are made, the sequence is substantially analogous, with differences that will be described in detail hereafter and that concern the opposite orientation of the hooks with respect to the sewing direction.

Furthermore, according to the invention, the possibility of is provided to apply tapes on fabrics fed continuously from rolls, by fitting feed reels on suitable supports, associated with means for feeding/guiding said tapes, cooperating selectively with the sewing members . According to the invention, devices for selecting the needles are also provided, which allow, on command, to independently lower every single sewing needle into a working position so as to make the stitches, or to lift them into an inactive position in order to interrupt said stitches, thus creating isolated figures according to the working or inactive positions of the various needles.

By using these selection and independent drive devices of the needles according to the invention, it is possible to achieve an unlimited variety of isolated patterns.

The method according to the invention provides, when sewing with chain stitch, the following sequences:

- the needles are at the upper dead point of their travel, the fabric being treated is moved by the width of one stitch in the direction required by the ornamental pattern to be made, and the lower needles and thread feeders are rotated until the hooks of the needles are facing the same way as the sewing direction and the exit holes of the thread feeders are at "10 o'clock" with respect to the hooks of the needles at "6 o'clock";

- the movement of the fabric is stopped and the needles begin their descent;

- the needles pass through the fabric being treated and reach the lower dead point of their travel; - the lower thread feeders carry out a complete clockwise rotation during which the threads, held at one end by the previous stitches, wind around the needles;

- the needles begin their upward travel and their hooks attach the threads drawing them in the form of eyelets through the fabric being treated and through the eyelets formed by the previous stitches;

- the needles approach the upper dead point moving towards their initial position, ready to make the next stitch according to the desired ornamental pattern to be made; - during the following descent of the needles, the eyelets formed by the strips of thread tied to the previous stitches and by the strips of thread coming from the reels rest on the fabric and slide along the stems of the needles, while the latter perforate and penetrate the fabric .

During the creation of ornamental effects with moss stitch and chenille stitch, the sequences are substantially analogous, the only differences being: in the initial step the needles are made to rotate until their hooks are facing in the opposite direction to the sewing direction and the lower thread feeders are directed with their exit holes at "10 o'clock" with respect to the hooks at "6 o'clock"; as a consequence, when the needles descend, the eyelets of the threads, no longer held by the stems of the needles, are released by the hooks and remain erect, forming the characteristic hair of the moss/chenille effect.

According to the invention, the sewing thread can be of 4 or more different colors automatically selectable during the treatment according to the ornamental pattern to be made.

For this purpose, each rotating element of the lower thread feeders is connected at the lower part to an ejector in turn mounted above a collector into which tubes . coming from the same number of pipes converge, in each of which a different colored thread slides, fed by underlying reels.

Each pipe is provided with a thread-stopper able to stop, inside the pipe, the thread present therein. According to the invention, each rotating element of the lower thread feeders cooperates with means for holding the end of the thread in use at the exit of the thread feeder's hole, and with thread cutting means able to cut the thread in use after the last stitch made.

According to the invention it is also possible to select the needles that must or must not simultaneously sew, lowering them into working position or leaving them in an inactive position according to the needs of the ornamental pattern to be made.

In order to prevent the stitches from unthreading, at the beginning and end of each section of isolated sewing, a step is provided to fix the stitches, consisting of the repetition of a certain number of stitches.

The method for making isolated patterns comprises the following sequences :

- at the end of the previous ornamental pattern the needles stop at the upper dead point, the thread cutting means is activated so as to cut the threads in use and the thread holding means is activated so as to hold the ends of the threads in use;

- according to the ornamental pattern to be made, the needles that have to make the isolated patterns provided in the first phase of the ornamental pattern are lowered into working position, by means of the needle selection devices;

- the sewing machine is set into motion, the selected needles descend, pass through the fabric and reach the lower dead point; - the lower thread feeders carry out a complete clockwise rotation during which the threads, held at one end by the holding means, wind around the needles;

- the needles start their upward travel and the hooks of the selected needles attach the threads, drawing them in the form of eyelets through the fabric;

- while the needles approach the upper dead point, the fabric being treated is moved by the width of a stitch in the direction required by the ornamental pattern to be made, and the needles and lower thread feeders are made to rotate until the hooks of the needles are facing in the same sewing direction and the exit holes of the thread feeders are at "10 o'clock" with respect to the hooks of the needles positioned at "6 o'clock";

- the movement of the fabric is stopped, the needles descend and fix the beginning of the stitches by repeating the first stitches several times; after the third stitch the thread-holders are opened; - the selected needles make the stitches, achieving the isolated patterns provided in the first step of the ornamental pattern to be made;

- the selected needles fix the end of the stitches by- repeating the last stitches several times; - the sewing machine stops automatically with the needles in the upper dead point, the cutting means is driven so as to cut the threads, the holding means is driven so as to hold the ends of the threads in use;

- according to the ornamental pattern to be made, the needles that have to make the isolated patterns provided in the second step of the ornamental pattern are lowered into the working position by means of the needle selection devices;

- the procedures described heretofore are repeated until, step after step, the ornamental pattern to be made is completed.

The procedure for applying tapes on the fabric being treated with chain stitches is identical to the one used for making ornamental stitches with chain stitches, the only difference being that first the reels holding the tapes must be mounted onto the suitable supports, the leading ends of the tapes must be fed into the rotating members of the upper sewing devices, and inserted into the slits of suitable tape guides in front of the sewing needles with which the tapes are to be applied.

According to the ornamental pattern to be made, different decorative effects can be obtained, such as: - flat-tape, during segments of straight stitching or ample-radius curves;

- rising-tape, during segments of stitching with a medium- short radius;

- curling-tape, during segments of stitching with a very short radius.

According to the invention, a procedure for changing the color of the threads fed by the lower sewing members is also provided, which is repeated every time the color of the thread in the stitches has to be changed, according to the ornamental pattern to be made.

According to the invention, the color-change procedure is carried out with the following sequences:

- when the use of a thread of a particular color has ended, the needles stop at the upper dead point of their travel; - the cutting means, whose blades cut the threads in use, is driven;

- all the thread-brakes are blocked, the thread-recovery device is driven, which in this specific case exerts a traction on all four threads; the three colored threads not in use, blocked by their relative thread-stoppers and- already having a previously created reserve, are not affected while the threads in use, not blocked in their pipes but blocked by the lower thread-brakes, are pulled by the thread-recovery device and extracted from the holes of the feeders and the ejectors;

- all the thread-stoppers are closed and all the thread- brakes are opened;

- the thread-recovery device is driven, which exerts a traction on the threads of the color used previously which, being blocked by the thread-stoppers but free in the thread-brakes, unwind from their reels creating a reserve equal to that of the threads of a different color; the thread-brakes are put in a condition so as to provide the threads with the normal working tension;

- the ejectors are driven and the thread-stoppers of the new colored threads are unblocked; the latter, being free, are sucked up and pushed into the vertical pipes of the thread-feeders, finally exiting horizontally from their upper holes for the length of the previously created reserve;

- the thread-holding cylinders are driven, and the ends of the threads are blocked; - the needles descend, pass through the fabric and arrive at the lower dead point;

- the thread-feeders are driven, which carry out a complete clockwise rotation and the threads, held by the thread- holders, wind around the needles; - the needles begin their upward travel, their hooks attach the threads and draw them through the fabric up to the upper dead point;

- the fabric being treated is moved the width of a stitch in the direction required by the ornamental pattern to be made and the needles and the lower thread-feeders are rotated until the hooks of the needles are facing the sewing direction and the exit holes of the thread-feeders are at "10 o'clock" with respect to the hooks of the needles at "6 o'clock"; - the needles descend, making the first points of the stitching segment with the new color; after the third stitch has been made, the thread-holders are opened.

The procedure above is repeated every time the color of the stitches has to be changed, according to the ornamental pattern to be made.

A similar procedure is used to create the moss/chenille effects with different colors. By varying the travel of the needle, within certain limits, it is possible to create chains of different widths during the chain stitch sewing and to apply tapes with chain stitch sewing and with a nap of different lengths during the creation of moss/chenille effects. BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein: - fig. 1 is a schematic view of a multi-needle sewing machine according to the present invention;

- fig. 2 is a three-dimensional view from below of a supporting bar of the machine in fig. 1;

- fig. 3 is a three-dimensional section of the upper sewing members according to the invention; figs. 4a and 4b show a longitudinal section of respectively the upper and the lower sewing members according to the invention;

- fig. 5 is a longitudinal section of the thread recovery device;

- fig. 6 shows some examples of continuous decorative stitches;

- fig 7 shows some examples of decorative stitches and isolated patterns; - fig. 8 shows some examples of moss/chenille effects.

DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT

With reference to fig. 1, a sewing machine 10 according to the present invention is shown, of the automatic multi- needle quilting type, with electronic control, which comprises, as essential parts, an inlet assembly 10a, a sewing assembly 10b and an outlet assembly 10c.

The inlet assembly 10a feeds a textile material 11, which slides on plates 14 (fig. 4a), on which the stitches are to be made, and is managed and controlled by a control unit 13, so as to move the textile material 11 in any direction whatsoever, backwards-forwards or left-right, in order to make any kind of design. The sewing assembly 10b comprises a supporting bar 21, upper sewing members 30 and lower sewing members 31.

The upper sewing members 30 are controlled by levers 16, mounted on bars 17, and by levers 19 solid with respect to the supporting bar 21, which impart to said upper sewing members 30 an alternate ascending-descending motion.

On the flanks of said supporting bar 21, inside antifriction guides 22, a toothed belt 23 slides, made of flexible plastic material with teeth on both sides. The toothed belt 23 is held tense between a return pulley 24 and a guide pulley 25, both idle and mounted at a first end of the supporting bar 21, and a drive pulley 26 and an idle guide pulley 27, mounted at a second end of the supporting bar 21 (fig. 2). The pulleys 24-27 are toothed in a manner mating with the toothed belt 23. The drive pulley 26 is mounted on the shaft of a command motor 29, for example of the electric type, managed by the control unit 13, and is able to impart to the toothed belt 23 movements with a cadence, amplitude and direction that vary according to the signals received from the control unit 13, according to the type of operation to be performed, for example set by the operator at the start-up of the machine 10.

The upper sewing members 30 are provided with connection elements 32, able to be associated with housings 28 of the supporting bar 21 (fig. 2).

Each upper sewing member, 30 also comprises a supporting element 34 which protrudes laterally with respect to the supporting bar 21. A chamber 35 is made in said supporting element 34, inside which two bearings 36 are housed in which a tube 37 rotates, outside of whose lower end, protruding from the chamber 35, a toothed pulley 38 is fixed.

Inside the lower end of the tube 37 a bushing 39 slides in a vertical direction, to the lower end of which a pressure finger 40 is fixed, visible in figs. 4a and 4b, protruding downwards and having a hole able to house a sewing needle 41 of the hook type. In the internal part, cup-shaped, of the bushing 39, the lower end of a helical spring 42 is housed, whose upper end rests on the lower part of a sliding bushing 43 fixed solidly inside the upper part of the tube 37.

According to the invention, the bushing 39 can slide upwards inside the tube 37 overcoming the thrust of the helical spring 42, but a vertical groove made on its outside, inside which a suitable pin fixed to the inside of the tube 37 slides, prevents it from rotating and descending further than the lower end of said tube 37.

The sliding bushing 43, solid with the tube 37, has a hole with a polygonal section, in this specific case of a triangular shape, in which a hollow rod 44 slides, having a polygonal external profile mating with that of the hole of the sliding bushing 43, and an axial hole with a diameter suitable to house the needle-bearing rod 45; furthermore, the upper part of the rod 44 has a circular chamber 46 delimited by two rings, a lower one 46a and an upper one 46b coinciding with the end of the rod 44.

A pneumatic cylinder 18, in this specific case of the simple effect type, is mounted solidly above the upper ring 46b, and its rod 49 protrudes from the upper head, while the lower head of the pneumatic cylinder 18, solid with the upper ring 46b, has a hole coinciding with the axial hole of the rod 44 and having the same diameter.

The rod 49 of the pneumatic cylinder 18 has an axial hole with a diameter suitable to house the needle-bearing rod 45, and an external polygonal section that slides inside a bushing solid with the upper head of said cylinder 18, whose hole has a mating polygonal profile.

At its upper end the rod 49 has a reinforcement ring 50 in which a threaded hole is made, perpendicular to the axis of said rod 49, where a screw 51 operates to clamp the needle-bearing rod 45. A helical spring 48 is housed inside the pneumatic cylinder 18, acting between the lower head and the piston of the pneumatic cylinder; furthermore, a tube to feed compressed air, connected to a respective electro-valve, is connected to the upper head of the pneumatic cylinder 18. Each pneumatic cylinder 18 is connected to an independent electro-valve so that, by driving individually said electro-valves according to the ornamental pattern to be made, it is possible to vary the condition of the needles in a working or inactive position as desired, creating in this way an unlimited combination of isolated patterns.

According to the invention, the possibility of applying tapes 81 on the fabric being treated with chain stitches is also provided.

For this purpose, on each pneumatic cylinder 18 a vertical support 82 is fixed, on whose horizontal arm a reel 83, from which the tape 81 unwinds, is able to rotate. The tape 81 passes through suitable slits made in the rings 46a and 46b, and through a vertical groove made on the external surface of the tube 37 which allows it to pass under the bearings 36 and the pulley 38, and therefore reaches the slit of the tape guide 84, fixed to the pressure finger 40 opposite the needle 41. Since the tape guide 84 is solid with respect to the pressure finger 40, it follows all the rotations imparted to the latter by the pulley 38 based on the changes in sewing direction according to the ornamental pattern to be made, and its slit maintains the tape 81 always opposite the needle 41 according to the direction of each following stitch, so that the needle 41 will fix the tape 81 to the fabric 11 being worked with chain stitches always centered in the same tape 81.

Inserting the needle-bearing rod 45 with the needle 41 fixed to its end from the hole in the rod 49 of the pneumatic cylinder 18, the needle 41 will pass through the hole in the rod 49, through the hole in the lower head of the pneumatic cylinder 18, through the hole in the hollow rod 44 and through the hole in the pressure finger 40, and will partly exit from the latter.

According to the invention, a graduated stopping and orientation ring-nut 47 is provided, equipped with a clamping screw, which, suitably fixed to the needle-bearing rod 45, will determine, by resting on the upper end of the rod 49, the correct protrusion from the pressure finger 40 and the correct orientation of the hook of the needle 41, previously aligned with the index of the ring-nut.

When an upper sewing member 30 is mounted on the bar 21, the toothed pulley 38 is mechanically connected to the toothed belt 23 so that any movement of the latter is transmitted to the tube 37 and, consequently, to the rod 44, to the pneumatic cylinder 18, to the needle-bearing rod 45 and finally to the hooked needle 41. According to the invention, a plurality of actuators 52 is provided, fixed to the bar 17 in positions corresponding to those of the lower sewing members 31.

The actuators 52 are fork-shaped and two bearings 53 are fixed to the internal parts of the two arms of said forks, coaxially one on each side; the external circumferences of the bearings 53 are inserted into the circular chambers 46, between the rings 46a and 46b, one on each side of the rods 44 of the upper sewing members 30 mounted on the supporting bar 21.

The lower sewing members 31 are solid with the base 12 of the sewing machine 10 and are supported by a plurality of supports 54 fixed to the base 12 of said machine.

In this specific case, four pipes 55 are housed in the lower part of each of the supports 54, inside which the threads 56 pass; thread-stoppers 57 act inside each of these pipes 55, driven by simple-effect pneumatic cylinders 58 commanded by respective electro-valves.

In the intermediate part of the supports 54 collectors 59 are mounted, in each of which, in this specific case, the four lower holes, into which the four tubes coming from the pipes enter converge, inside the collectors 59, into a single hole that exits on their upper side. In correspondence with the hole of each collector 59 the suction nozzle of a coaxial ejector 61 is fixed, whose blowing nozzle is inserted inside a bearing mounted in the lower hole, concentric, of the rotating feeder 63, which rotates on the bearings 64 mounted on the upper part of the supports 54. According to the invention, said feeder 63 consists of a rotating element inside which a vertical pipe 62 is made, concentric to the base but gradually more eccentric moving upwards, whose upper hole, inclined at 90° towards the center, is positioned adjacent to the hook of the sewing needle 41 after its point has passed through the fabric 11 being treated, at a height greater than that of said hook.

The rotating feeders 63 are solid with the toothed pulleys 65 that, by means of the toothed belts 66 and the toothed pulley 67 mounted on the shaft of the electric motor 68, commanded by the control unit 13, follow all the movements of the electric motor 68, imparting them to the rotating feeders 63. A simple-effect pneumatic cylinder 69 is mounted vertically on each rotating feeder 63 and, when driven, holds the end of the thread 56 that protrudes from the hole of the feeder 63.

According to the invention, in correspondence with each lower thread feeder, a simple-effect pneumatic cylinder 70 is also provided, mounted horizontally which, upon command, drives a thread-cutting blade 71 able to cut the thread 56 in use after the last stitch made.

In the lower part of the base of the sewing machine 10 the reels 72 are housed, from which, in this specific case, the different-colored sewing threads 56a, 56b, 56c, 56d unwind, each passing through a pneumatic thread-brake 73 before arriving at a thread-recovery device. The latter consists of a fixed bar 74 and a mobile bar 75, mounted on oscillating arms 76 pivoted to a suitable shaft that, commanded by a pneumatic engine 80 by means of the pulleys 77, 79 and the toothed belt 78, makes the arms 76 rotate from position "A" to "B" , exerting a traction on the threads 56. The functioning of the machine 10 is described hereafter. When the sewing machine 10 has to make stitches with chain stitch with 4 or more different colors, or create ornamental effects with moss stitch or chenille stitch, on a continuously fed fabric 11, the procedure is as follows.

With the machine off, a relative button is pushed, provided on the command panel of the control unit 13, and automatically : - The thread-stoppers 57 close, the thread-brakes 73 open, the motor 29 moves the belt 23 into the correct starting position by means of the pulley 27; the motor 68 makes the feeders 63 rotate into the correct starting position, by- means of the pulley 67, the belts 66 and the pulleys 65, with the exit holes of the threads at "10 o'clock"; the motor 10 makes the bar 75 complete a semi-rotation from "A" to "B", exerting pressure on threads 56 that, stopped by the closed thread-stoppers 57, can only unwind from the respective reels 72 for a pre-established length, corresponding to the movement of the bar 75, passing through the pneumatic thread-brakes 73, which are open, thus creating a reserve of thread;

- the upper sewing members 30 are mounted on the supporting bar 21 of the sewing machine 10 in correspondence with the lower thread-feeding devices 31 to be used, inserting the bearings 53 of the actuators into the chambers 46;

- the needle-bearing rods 45 are inserted into the holes of the rods 49 of the pneumatic cylinders 18, with the needles 41 facing downwards, and they are clamped with screws 51 at the height defined by the ring-nuts 47, taking care that the indexes of said ring-nuts 47, which show the position of the hooks of the needles 41, are facing "6 o'clock";

- on the command panel of the control unit 13, the icon corresponding to the color, for example "a", with which the ornamental pattern is to be started is pressed and, automatically: the pneumatic cylinders 58a, corresponding to the threads of the selected color, open and the thread- stopper fingers 57a, retracting, leave the threads 56a free; the ejectors 61 are then driven, the action of which thrusts said threads 56a into the holes 62 of the feeders 63, causing them to exit horizontally from the terminal orifices of said holes for a length allowed by the reserve of thread created previously; the thread-holding cylinders 69 are then driven, and hold the ends of the threads 56a of the chosen color; finally, the pneumatic cylinders 18 are fed by the respective electro-valves, so that their pistons are thrust downwards, overcoming the action of the helical springs 48 and the needles 41, fixed to the rods 45, which in turn are fixed to the rods 49 of the pneumatic cylinders 18, are brought into the working position;

- an appropriate button, for example "START", of the sewing machine 10 is pushed and, automatically: the levers 16 and the bar 17 slowly descend, the actuators 52, by means of the bearings 53 engaged in the chambers 46, thrust the rods 44 downwards with the solid pneumatic cylinders 18, whose rods 49 in turn draw the needle-bearing rods 45 and the needles 41, while the levers 16 and the supporting bar 21, with a coordinated movement, slowly lower the supporting elements 34 with the respective tubes 37 and with the pressure fingers.40 which go and press the fabric 11 being treated; - when the points of the hook-type needles 41 have passed through the fabric 11 and have exited under the plates 14 of the sewing machine 10 where the fabric slides, the feeders 63 are made to fully rotate in a clockwise direction, so that the threads 56a wind around the needles 41, the needles 41 then begin to move upwards and their hooks attach the threads 56a, pulling them through the fabric 11;

- while the needles 41 move upwards, drawing the threads 56a, the fabric being treated 11 is moved by the width of a stitch in the direction required by the ornamental pattern to be made, the needles 41 are made to rotate by the motor 29 and the belts 23 until their hooks are facing the sewing direction of the following stitch, and the thread-feeders 63 are rotated by the motor 68 and the belt 66 until the exit holes of the threads 56a are at about "10 o'clock" with respect to the hooks of the needles 41 in the "S o'clock" position; - the needles 41 descend, perforate the fabric 11 and reach the lower dead point, the thread-feeders 63 are made to rotate clockwise by 360°, the threads 56a wind around the needles 41;

- the needles 41 move upwards, their hooks attach the threads 56a and draw them through the fabric 11 up to the upper dead point, the fabric 11 is moved by the width of the following stitch, while the eyelets formed by the two strips of thread are held by the stems of the. needles 41, the hooks of the needles 41 and the feeders 63 are made to rotate in correspondence with the new sewing direction, then the needles 41 descend and, while they penetrate the fabric 11, the eyelets formed by the strips of thread tied in the previous stitch and by the strips of thread coming from the reels 72 rest on the fabric 11, sliding along the stems of the needles 41;

- the needles 41 reach the lower dead point, the thread- feeders 63 are made to rotate 360° clockwise, the threads 56a wind around the needles 41;

- the needles 41 move upwards, their hooks attach the threads 56a and draw them through the fabric 11 and the eyelets of the previous stitches taking them to the upper dead point and so on;

- after the third stitch has been made, the thread-holders 69 are opened, and the needles 41 continue to carry out the ornamental stitches according to the ornamental pattern to be made until the color in use is finished.

The succession of consecutive eyelets formed by the threads 56a that the needles 41 rest on the fabric 11 at every stitch point, and through which they feed the eyelets of the following stitch points as the stitching proceeds, gives shape to the desired ornamental pattern.

When the multi-needle sewing machine 10 has to make ornamental patterns with moss stitch and chenille stitch, the procedure is practically identical to the one with chain stitch, except that the hooks of the needles 41 must be facing in the "12 o'clock" position instead of the "6 o'clock" one. As a consequence, during the descent of the needles, the eyelets of the threads 56a, no longer held by the stems of the needles 41, are released by the hooks of the needles 41 as soon as the latter begin to descend, and remain upright, forming the characteristic nap of the moss/chenille effect. When, according to the ornamental pattern to be made, it is necessary to create patterns with isolated figures, the procedure is as follows : at the end of the previous ornamental pattern, the thread-cutting cylinders 70 are driven, whose blades 71 cut the threads in use, and the thread-holding cylinders 69 are driven, which hold the ends of the threads 56 in use; - according to the ornamental pattern to be made, the control unit 13 drives the electro-valves relating to the cylinders 18 of the needles 41 that have to make isolated designs during the first step of the ornamental pattern to be made and the selected needles 41 lower into the working position, while the others remain in the upper inactive position; - the sewing machine 10 is set in motion, the selected needles 41 descend, pass through the fabric 11 and reach the lower dead point;

- the lower thread-feeders 63 perform a complete clockwise rotation during which the threads 56, held at one end by the thread-holders 69, wind around the needles 41;

- the needles 41 begin their upward travel and the hooks of the selected needles 41 attach the threads 56, drawing them in the form of eyelets through the fabric 11, while the pressure fingers 40, under the action of the springs 42 maintain the fabric 11 adherent to the sliding plate 14;

- while the needles 41 approach the upper dead point, the fabric 11 being treated is moved by the width of a stitch in the direction required by the ornamental pattern to be made; the needles 41 and the lower thread-feeders 63 are made to rotate until the hooks of the needles 41 are facing in the same sewing direction and the exit holes of the thread-feeders 63 are in the "10 o'clock" position .with respect to the hooks of the needles in the "6 o'clock" position;

- the movement of the fabric 11 is stopped, the needles descend and perform the fixing of the beginning of the stitches, repeating the first stitch points a few times; after the third stitch point has been made, the thread- holders 69 are opened;

- the selected needles 41 make the stitches that go to form the isolated figures of the first step according to the ornamental pattern to be made;

- when the stitching of the isolated figures of the first step has ended, the selected needles 41 perform the fixing at the end of the stitches, repeating the last points a few times;

- the sewing machine 10 automatically stops with the needles 41 in the upper dead point, the thread-cutting cylinders 70 are driven and the blades 71 cut the threads 56; the thread-holding cylinders 69, which hold the ends of the threads 56, are driven; - according to the ornamental pattern to be made, the control unit 13 drives the electro-valves relating to the cylinders 18 of the needles 41 that have to make isolated drawings during the second step of the ornamental pattern and the corresponding needles 41 descend into the working position while the others remain in the upper inactive position;

- the procedures described heretofore are repeated, step by step, until the ornamental pattern is complete.

When, according to the ornamental pattern to be made, it is necessary to apply tapes 81 on the fabric being treated, the procedure is the same as the one used to make ornamental stitches with chain stitch, the only difference being that, before starting up the sewing machine 10, it ^"is necessary to: - mount the reels 83 containing the tapes 81 on the relative supports 82;

- feed the heads of the tapes 81 through the slits made in the rings 46a and 46b, the tubes 37 and the pulleys 38;

- insert the heads of the tapes 81 in the slits of the tape-guides 84;

- bring the heads of the tapes 81 right up to under the hook-type needles 41.

Starting the sewing machine 10, the chain stitches made by the needles 41 will fix the tapes 81 on the fabric being treated with chain stitches always centered on said tapes 81.

When, according to the ornamental pattern to be made, it is necessary to change color, the procedure is as follows: - the sewing machine 10, having reached the last stitch point made with the previous color, automatically stops in the following conditions: needles 41 in the upper dead point, thread exit holes of the thread-feeders 63 in "10 o'clock" position with respect to the hooks of the needles 41 in "6 o'clock position", thread-stoppers 57b, 57c and 57d of the three colored threads not in use closed, thread- stoppers 57a of the threads 56a of the previous color open, thread-brakes 73 closed; - the pneumatic cylinders 70 are driven and the blades 71 cut the threads 56a of the previous color;

- the motor 80 is driven, the mobile bar 75 rotates from "A" to "B" drawing the threads 56a of the previous color which, being blocked by the closed thread-brakes 73, are extracted from the pipes 62 of the thread-feeders 63 and from the ejectors 61;

- all the thread-stoppers 57a, 57b, 57c and 57d are blocked and the thread-brakes 73 are opened;

- the motor 80 is driven and the mobile bar 75 rotates from "A" to "B" drawing the threads 56a of the previous color which, being blocked by the thread-stoppers 57a, are unwound from the reels 72a passing through the open thread- brakes 73; the reserve of threads of the previous color 56a is therefore restored; the other colored threads do not undergo any variations, as their reserves were created previously;

- the thread-brakes 73 are placed in a normal working condition;

- the ejectors 61 are driven, the thread-stoppers 57b are opened, which control the threads 56b of the new color that, drawn by the action of the ejectors 61, are thrust into the vertical holes 62 of the ejectors 63 and exit horizontally from the upper holes for the length allowed by the reserve of thread;

- the thread-holders 69 are driven, which hold the ends of the threads 56b;

- the needles 41 are slowly lowered down to the lower dead point;

- the feeders 63, commanded by the motor 68 and the belts 67, carry out a complete clockwise rotation, winding the threads 56b around the needles 41;

- the needles 41 ascend, their hooks attach the threads 56b and draw them through the fabric 11 up to the upper dead point, the fabric 11 is moved by the width and in the direction of the next stitch point according to the ornamental pattern to be made, the hooks of the needles 41 and the feeders 63 are made to rotate in correspondence with the new sewing direction;

- the needles 41 descend and begin the next stitch with the thread 56b of a new color; after the third stitch point has been performed, the thread-holders 69 are opened.

The procedure is repeated every time the color of the thread of the stitches needs to be changed, according to the ornamental pattern to be made.

An analogous procedure is used to create ornamental effects with moss stitch and chenille stitch with different colors . According to the invention, by varying within certain limits the travel of the needles 41, it is possible to create chain stitches of different widths when sewing with chain stitches and nap of different heights when creating moss/chenille effects. It is clear that modifications and/or additions of parts and/or steps may be made to the machine 10 and the method as described heretofore, without departing from the field and scope of the present invention. It is also clear that, although the present invention has been described with reference to specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of devices for making decorative stitches with 4 or more colors with chain stitch or for creating ornamental effects with moss stitch and chenille stitch, or for applying tapes with chain stitches, the relative application methods and multi-needle sewing machines comprising such devices, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

For example, the electric motors, the pneumatic motors, the pneumatic cylinders provided by the present invention may be substituted by corresponding electro-mechanic, electromagnetic, hydraulic etc. actuators that carry out the same functions.

Claims

1. Automatic multi-needle sewing machine (10) for making continuous or isolated ornamental stitches with 4 or more colors with chain stitch and for achieving ornamental effects with moss stitch and chenille s.titch, on a fabric (11) continuously fed from roll to roll, said sewing machine of the automatic multi-needle type having upper sewing members (30) and lower sewing members (31), and at least a supporting bar (21) with which the upper sewing members (30) can be associated, characterized in that said upper sewing members (30) comprise a plurality of hook-type needles (41) movable with a rotary motion and an alternate vertical motion, and in that said lower sewing members (31) are solid with the base of the sewing machine (10) and comprise a plurality of lower thread-feeders (63) able to feed said hook-type sewing needles (41) with sewing threads (56) of different colors.

2. Sewing machine as in claim 1, characterized in that said lower thread-feeders (63) are supported by supports (54) and comprise thread-recovery means (74, 75), thread-brake means (73), thread-stopping means (57), thread-ejecting means (61), thread-holding means (69) and thread-cutting means (71).

3. Machine as in claim 1, characterized in that it comprises, for each of said needles (41), independent drive means (18) able to drive each needle (41) vertically and independently from the others so as to take them from an upper inactive position to a lower working position.

4. Machine as in claim 3, characterized in that said drive means consists of simple-effect pneumatic cylinders (18).

5. Machine as in any claim hereinbefore, characterized in that it comprises feed means for tapes (81) that unwind from reels (83) supported by supports (82), and guide means (84) able to take said tapes (81) constantly opposite the needles (41) in the direction of sewing of the next stitch point in order to be fixed to the fabric (11) with stitches always centered in the tapes (81).

6. Machine as in claim 1, characterized in that it also comprises attachment means (32) able to cooperate with housing means (28) for said supporting bar (21) so as to associate said upper sewing members (30) with the sewing machine (10) .

7. Machine as in claim 1, characterized in that it also comprises support means (34), on which rotary movement means (37, 38, 43, 44, 18, 49) and vertical movement means (39, 40, 44) for said hook-type needles (41) are mounted.

8. Machine as in claim 7, characterized in that said rotary movement means comprises at least one fixed part (34) associated with said supporting bar (21) and a part (37) mobile with respect to said fixed part (34) and mechanically connected to connection means (38).

9. Machine as in claim 7, characterized in that said vertical movement means comprises containing means (40, 44,

47, 49) able to house the hook-type needles (41) and their rods (45).

10. Machine as in claim 9, characterized in that said vertical movement means also comprises at least one hollow rod (44) able to slide vertically inside a bushing (43) in which, however, it cannot rotate.

11. Machine as in claim 10, characterized in that said rod (44) is also mobile in a rotational direction together with said mobile part (37).

12. Machine as in claim 11, characterized in that a bushing (39) is able to slide in said mobile part (37), contrasted elastically by a spring (42), a pressure finger (40) being associated with the lower end of said bushing (39).

13. Machine as in claims 3 and 12, characterized in that said independent drive means (18) comprises, for each of said needles (41), a rod (49) inside which a needle-bearing rod (45) is inserted, the hook-type needle (41) that, in the working position, is inside said pressure finger (40) being associated at the lower end of said needle-bearing rod (45).

14. Machine as in claim 13, characterized in that a positioning ring-nut (47) is associated with said needle- bearing rod (45), and is able to determine the position in height of the hook-type needle (41) that, after passing inside the hollow rod (44), is in the working position inside the hole of the pressure finger (40).

15. Machine as in claim 13, characterized in that said rod (49) is associated with elastic means (48) so as to maintain the relative hook-type needle (41) in an upper inactive position when the relative drive means (18) is not driven.

16. Machine as in claim 10, characterized in that two rings (46a, 46b) are associated with the upper part of said hollow rod (44), defining a chamber (46) on which the external circumferences of respective bearings (53) press, one on each side of the hollow rod (44).

17. Machine as in claim 16, characterized in that it comprises a support (52) able to transmit ascending- descending movements to said hollow rod (44).

18. Machine as in claims 1 and 2, characterized in that said lower thread-feeding means (31) comprise reels (72) housed in the base of the sewing machine (10), and wherein said thread-brake means (73) has three positions: a first completely closed position, a second completely open position and a third working position able to supply a moderate tension to the threads (56).

19. Machine as in claim 2, characterized in that said thread-stopping means (57) comprises pipes (55) fixed to supports (54), inside each of said pipes (55) one of the different colored threads (56) passing, each of said pipes (55) being provided with drive means (58) able to stop the thread (56) present therein against the bottom of the pipe (55).

20. Machine as in claim 2, characterized in that said lower thread-feeders (31) comprise collectors (59) fixed to said supports (54), inside each of said collectors (59) four holes entering from below, converging into a single upper hole, a different colored thread (56) passing through said holes, said ejector means (61) comprising a blowing nozzle associated with a bearing solid with the lower part of a rotating feeder (63).

21. Machine as in claim 20, characterized in that said rotating feeder (63) is equipped with a hole (62) in whose lower part the blowing nozzle of the ejector (61) enters and whose upper end part exits below a needle plate (14) of the sewing machine (10) in proximity with the hook of the needle (41) and adjacent to the needle (41) when it is in the lower dead point of its descending motion.

22. Machine as in claim 21, characterized in that said rotating feeder (63) is able to rotate so that said hole (62) carries out concentric rotations around a relative needle (41).

23. Machine as in claims 2 and 20, characterized in that said thread-holding means (69) is mounted vertically in each of said rotating feeders (63) so as to hold, on command, the ends of the threads (56) which exit from the upper part of the holes (62) of the feeders (63) under the blowing action of the ejectors (61).

24. Machine as in claim 2, characterized in that said means to cut the sewing threads (56) consists of cylinders mounted horizontally on said supports (54) which drive the cutting means (71) so as to cut the sewing threads (56) on command after the last stitch made.

25. Machine as in claim 2, characterized in that said means to recover the sewing threads (56) consists of a fixed bar

(74) on which the threads (56) slide and of a mobile bar

(75) associated with oscillating arms (76) able to be displaced between two points ("A", "B"), in order to exert a traction on the sewing threads (56) whose development is increased correspondingly.

26. Method for sewing with chain stitch with 4 or more different colors, for creating ornamental effects with moss stitch and chenille stitch and for applying tapes with chain stitches on a continuously fed fabric (11), for a sewing machine as in any of the claims hereinbefore from 1 to 25, characterized in that it comprises at least a first sewing step with chain stitch with sewing threads (56) of a given color during which: - by means of rotatory motion transmission means (37, 38, 44, 49) said hook-type needles (41) are directed so that, at each stitching point, the hooks of said needles (41) are facing the sewing direction required by the ornamental pattern to be made in the case of sewing with chain stitch, or so that said hooks face in the direction opposite the sewing direction when ornamental effects are made with moss stitch and chenille stitch, and by motion transmission means (68, 67, 66, 65) the lower feeders (63) of the threads are directed so that at each stitching point the upper exit holes of the threads are in the "10 o'clock" position with respect to the hooks of the needles (41) in the "6 o'clock" position; - by alternate vertical movement means (16, 17, 19, 21, 53), alternate vertical ascending-descending movements are imparted to said hook shaped needles (41), of an amplitude such as to make the points of said needles (41) pass, at each stitching point, through the fabric (11) being treated;

- by winding means (63) of the sewing threads (56) fed by the reels (72) and controlled by the thread-brakes (73), at each stitching point said rotating feeders (63) are set into movement by the transmission means (68, 67, 66, 65), they are made to rotate clockwise by 360° when the needles

(41) are at the lower dead point of their travel and they wind said threads (56) around the stems of said needles

(42) whose hooks, while the needles (41) ascend, attach said threads (56) and draw them through the fabric (11) up to the upper dead point of their travel;

- to make the next stitch, the fabric (11) is moved by the width of one stitch in the direction required by the ornamental pattern to be made;

- by means of said rotatory motion transmission means (37, 38, 44, 49) the needles (41) are directed so that their hooks are facing the new sewing direction in the case of chain stitching, or in the direction opposite to the new sewing direction when ornamental effects with moss stitch and chenille stitch are to be created, and by means of rotatory motion transmission means (68, 67, 66, 65) the lower thread feeders (63) are directed so that the upper exit holes of the threads are at "10 o'clock" with respect to the hooks of the needles (41) positioned at "6 o'clock";

- by means of alternate vertical motion means (16, 17, 19, 21, 49) the needles (41) are made to descend and, while they penetrate the fabric (11), the eyelets of the threads (56) slide along the stems of said needles (41) and rest upon the fabric (11) itself in the case of chain stitches or the eyelets of the threads (56) are released by the hooks and remain upright when ornamental effects with moss stitch and chenille stitch are created.

27. Method as in claim 26, characterized in that it comprises at least a second step to make isolated patterns during which:

- cutting means (70, 71) cut the threads (56) and holding means (69) hold the ends of the threads (56);

- by means of the relative electro-valves, commanded by the control unit (13) according to the ornamental pattern to be made, the independent drive means (18) is driven, of the needles (41) which have to perform isolated patterns during the first step of the ornamental pattern and the selected needles (41) descend into the working position while the other needles (41) remain in an upper inactive position;

- the sewing machine (10) is started and the selected needles (41), driven by the vertical movement means (16, 17, 19, 21, 49), descend, pass through the fabric (11) and reach the lower dead point of their travel; - by means of rotatory motion transmission means (68, 67, 66, 65) the feeders (63) carry out a complete clockwise rotation, and the threads (56), held at their ends by the thread holding means (69), wind around the selected needles (41); - by means of vertical movement means (16, 17, 19, 21, 49) the selected needles (41) begin to ascend, their hooks attach the threads (56) and draw them under the form of eyelets through the fabric (H), the pressure fingers (40), under the action of the springs (42), maintain the fabric (11) adherent to the sliding plate (14);

- by means of vertical movement means (16, 17, 19, 21) the needles (41) reach the upper dead point, the fabric (11) is moved by the width of a stitch point in the direction required by the ornamental pattern to be made;

- by means of rotatory motion transmission means (37, 38, 44, 49) the needles (41) are directed so that their hooks are facing the new sewing direction in the case of stitching with chain stitch or the opposite direction to the new sewing direction when ornamental effects with moss stitch and chenille stitch are created;

- by means of rotatory motion transmission means (68, 67, 66, 65), the thread feeders (64) are directed so that the upper exit holes of the threads are at "10 o'clock" with respect to the hooks of the needles positioned at "6 o'clock";

- by means of vertical movement means (16, 17, 19, 21, 49), the needles (41) descend and perform the fixing at the beginning of the stitching of the isolated figures relating to the first step of the ornamental pattern to be made, repeating the first stitches a few times;

- the selected needles (41) make the stitches that form the isolated figures of relating to the first step of the ornamental pattern to be made;

- when the stitches that form the isolated figures of the first step are completed, the selected needles (41) perform the fixing at the end of the stitches, repeating the last stitches a few times; - the sewing machine (10) automatically stops with the needles (41) in the upper dead point, the thread-cutting cylinders (70) are driven and the blades (71) cut the threads;

- the electro-valves of . the pneumatic cylinders (18) relating to the needles (41) that have to make isolated figures during the second step of the ornamental pattern to be made are driven, and the selected needles (41) descend into their working position; - the sewing machine (10) starts up and the selected needles (41) begin to make the stitches that form the isolated figures of the second step of the ornamental pattern to be made and so on, until the ornamental pattern has been completed.

28. Method as in claims 26 and 27, characterized in that it comprises at least a third step of applying tapes (81) with chain stitches, which provides, in advance, the following steps: - mounting reels (82) containing the tapes (81) on suitable supports (83);

- making the heads of the tapes (81) pass through the slits made in the rings (46a, 46b) and in the rotating members (37, 38); - inserting the heads of the tapes (81) in the slits of the tape guides (84);

- bringing the heads of the tapes (81) under the needles (41);

- starting the sewing machine (10), when ornamental stitches are. made with chain stitch, so that the needles

(41) fix the tapes (81) to the fabric (11) with chain stitches according to the ornamental pattern to be made.

29. Method as in claim 26, characterized in that it comprises at least a fourth step where the color is changed during which:

- at the end of a segment of stitching with threads (56a) of a certain color, the needles (41) automatically stop in the upper dead point of their travel;

- by means of holding means (69) the ends of the threads (56a) of the previous color are held;

- by means of cutting means (70, 71) the threads (56a) of the previous color are cut;

- by means of holding means (69) the ends of the threads (56a) of the previous color are released;

- by means of thread control means (73) all the threads (56) are blocked;

- by means of thread-recovery means (75, 76), driven by the transmission means (77, 78, 79, 80), traction is exerted on all the sewing threads (56), in particular on the threads (56a) of the previous color, and due to this traction they are removed from the pipes (62) of the rotating feeders (63) and from the ejectors (61); - by means of thread-stopping means (57) all the threads (56) are blocked;

- by means of thread-control means (73) all the threads (56) are released;

- by means of thread-recovery means (75, 76), traction is exerted on all the sewing threads (56), in particular the threads of the previous color (56a), which are blocked by the thread-stoppers (57), and due to said traction they unwind from the respective reels (72) creating the reserve of ^~€Kread7^~ - the thread-control means (73) is placed into normal working position;

- by means of insertion means (61) a suction action is exerted in the pipes of the sewing threads (56);

- by means of selective clamping means (57, 58) the threads (56b) of the new color are released while the threads of other colors remain blocked;

- by means of the suction action of the insertion means (61) the sewing threads (56b) of the new color are thrust into the pipes (62) of the rotating feeders (63) and exit horizontally from the upper holes of said pipes (62) for the length allowed by the previously created reserve of thread;

- by means of holding means (69) the ends of the threads of the new color (56b) are retained;

- by means of vertical movement means (16, 17, 19, 21, 49), the needles (41) are lowered into the lower dead point of their travel; - by means of transmission means (65, 66, 67, 68) the rotating feeders (63) are made to carry out a complete clockwise rotation and the threads (56b) of the new color wind around the stems of the needles (41);

- by means of alternate vertical movement means (16, 17, 19, 21, 49) the needles (41) are made to ascend, their hooks attach the threads (56b) of the new color and draw them through the fabric (11) until they reach the upper dead point of their travel;

- the fabric (11) is moved by the width of a stitch in the direction required by the ornamental pattern to be made;

- by means of rotatory motion transmission means (37, 38, 44, 49) the needles (41) are directed so that their hooks face the new sewing- direction in the case of sewing with chain stitch, or in the direction opposite to the new sewing direction when ornamental effects with moss stitch and chenille stitch are created, and by means of rotatory motion transmission means (68, 67, 66, 65) the feeders (63) are directed so that the upper exit holes of the threads are at "10 o'clock" with respect to the hooks of the needles (41) positioned at "6 o'clock";

- by means of alternate vertical movement means (16, 17, 19, 21, 49) the needles (41) are lowered and begin the sewing step with the threads (56b) of the new color; after the third stitch point has been performed, by means of holding means (69) the ends of the threads (56b) of the new color are released.

30. Sewing method as in any claim from 26 to 29, characterized in that by varying the ascending-descending travel of the needles (41) it is possible to change the width of the eyelets of the stitch points, in the case of chain stitches, or the height of the nap when ornamental effects with moss stitch and chenille stitch are created.