YARN TWISTING MACHINE HAVING AXIAL MAGNETIC COUPLING FOR BOBBIN TO BOBBIN DIRECT TWISTING

Technical Field

Present invention is an improved version of a twisting machine disclosed in WO2005040465 and relates to a machine based on a magnetic coupling and capable of independently controlling twisting speed of a single or plurality of yarn(s) and winding speed of twisted yarns onto a bobbin and method of the same, the machine of the invention can also be used for yarn braking.

BACKGROUND OF THE INVENTION

As detailed in WO2005040465 conventional yarn twisting includes hollow spindle, two-for-one, and ring twisting methods. With the known twisting methods various yarn twisting configurations including S-twisting, Z-twisting, false twisting can be achieved to realize, these known twisting methods, however, includes certain disadvantages as mentioned in WO2005040465.

There are numerous of patent applications in the art relating to twisting machines in general, therefore only the following proposals have been considered to incorporate to this application in particular as these proposals relate to driving bobbin winding unit and maintaining stationary the carrier on which the bobbin is placed.

US 3,406,511 discloses a machine having a main shaft in which yarns are fed, a rotatable disc, an outer container delimiting balloon formation of yarn surrounding the outer diameter of the rotatable disc, an internal container contacting the bobbin onto which twisted yarns are wound, plurality of magnets placed radially (inside of the balloon) to the container for rotating thereof and corresponding oppositely poled magnets (outside of the balloon). Threading of yarns from untwisted bobbins to the machine of US 3,406,511 is difficult, and moreover an outer container is required to prevent from hitting the yarn balloon to the magnets.

In US 3,406,511 , winding unit for winding of twisted yarns to the bobbin is driven via a radial magnetic coupling and yarns are forced to pass through the magnets. As the radial coupling must be larger than the upper body of the machine this would lead to a costly solution in terms of equipment material and limitation in operating the machine at higher winding speeds.

US 3,368,336 discloses a machine which is driven directly of the machine of US US 3,406,511. In addition to the above disadvantages, it is needed a considerable space between the rotor and the stator for enabling the yams to pass smoothly, which gives rise to a certain inefficiency in transmitting motion to bobbin winding unit.

As the above-mentioned twisting machines, the bobbin carrier of US 3,834,146 is held stationary via radial magnets. Furthermore, yarn-twisting speed is dependent to winding speed of twisted yarns onto bobbin as bobbin winding unit is driven from twisting shaft.

In EP644281 energy for winding twisted yarn onto bobbin is transmitted to the inside of the balloon via a slip-ring arrangement. As a skilled person would appreciate that a slip-ring arrangement is not efficient at higher speeds, moreover, as a slip-ring arrangement generates sparks during operation, fire possibility is always a risk that should be avoided during machine operation.

In US 6,047,535 energy required to wind twisted yarn onto the bobbin is provided inside the balloon via radial inductance and communication is similarly performed via inductance. This arrangement causes not only the path of the yarn to get narrow but also decrease the efficiency of the machine as a reasonable space should be formed between inductance pairs to allow the yarn balloon to get therethrough. In addition to these disadvantages, the machine of US 6,047,535 proposes a costly solution as operation sequences should be maintained at relatively high levels.

In the prior art twisting machines, the carrier holding the bobbin onto which twisted yarns are wound is held stationary through magnets placed radially around the shaft axis, so the yarn balloon rotating around the shaft axis always passes through the magnets. This bears a certain risk that the yarn balloon can be tangled to the machine parts out of the balloon like magnets and ruptured. Furthermore, stretching of yarn due to tension differences along the yarn should be minimized for free movement of yam. Moreover in the art, yarn threading to the machine is considerably difficult.

With the known twisting machines, higher machine speeds cannot be not achieved due to extremely high centrifugal forces occurred as radially placed magnets around the carrier. Furthermore, in most twisting machines, yam twisting speed is not independent from the winding speed of the twisted yarn onto bobbin.

On the other hand, it has been experienced by the inventor that the planetary mechanism comprising mechanical components including belt-pulley mechanism, gear pairs requires a considerable effort to assemble the machine and, in use, substantial vibration increases at relatively high speeds due to the number of mechanical components of the planetary mechanisms. In addition to that, the machine of WO2005040465 is relatively heavy and costly due to the number of mechanical components of the planetary mechanisms.

As known by an ordinary person in the art, during yam twisting, yarn can be folded on account of tension differences along the yarn, which would prevent smooth streaming of the twisted yam. To overcome this problem, a yarn brake increasing tension on the yarn by applying friction force thereon can be provided. The magnetic coupling according to the invention can provide a yam brake for two-for- one twisting machines in particular.

DESCRIPTION OF THE INVENTION

One object of the present invention is to increase yarn twisting efficiency by independently controlling the twisting speed and the winding speed of the twisted

yarns onto bobbin by use of a machine being relatively light in weight and simple in design.

Another object of the present invention is to reduce centrifugal effects, so providing twisting at higher speeds and prevent the yarn balloon from tangling to an external component by transmitting the motion of the main shaft to an upper level in axial direction through a magnetic coupling and/or holding the bobbin carrier stationary through a magnetic coupling.

These objects are achieved by a twisting machine having a main shaft to which a yarn or a plurality of yarns is/are introduced in use and from which the yarns or the plurality of yarns is/are taken out in use, and the main shaft being driven by a drive element; a twisting disc being associated with the main shaft and being in contact with the yarn or plurality of yarns taken out of the shaft while rotating in use; a winding unit driven by another drive element for winding yarn or yarns passed through a yarn guide onto a bobbin, the yarn or yarns forming a yarn balloon contacting the twisting disc; and a stationary carrier holding the bobbin, characterized in that an axial magnetic coupling is provided in the shaft axis direction for holding the carrier stationary.

The invention further comprises a method for holding the carrier stationary via an axial magnetic coupling according to the twisting machine of the invention.

According to the preferred embodiment of the invention, holding the carrier stationary via magnetic coupling is achieved through magnets connected to the body of the machine, these magnets being provided underside a disc such that the magnets circularly disposed around the axis of the shaft and corresponding magnets oppositely poled with the above mentioned magnets are provided upper side of the disc such that the magnets circularly disposed around the axis of the shaft.

According to a preferred embodiment of the invention, driving force to the yarn winding unit provided from another motor is transmitted to the upper level of the disc and the carrier by an axial magnetic coupling in the shaft axis direction.

To achieve the magnetic coupling, according to the preferred embodiment of the invention, a number of magnets being associated with the other motor are disposed underside of the disc in a circular arrangement, and a number of corresponding magnets oppositely poled with the above mentioned magnets are disposed upper side of the disc. The magnets at the upper side are associated with the bobbin winding unit. Therefore, drive force provided by the other motor is transmitted magnetically in axial direction through magnets oppositely poled and disposed circularly around shaft axis and therefore bobbin winding unit can be driven.

The invention further comprises a method for driving the bobbin unit via an axial magnetic coupling according to the twisting machine of the invention.

Consequently a twisting machine which is more compact, having entire driving mechanisms inside the yarn balloon, not having an external component outside of the yarn balloon, being independently controllable of twisting speed and the winding speed, and being capable of operating relatively high speeds and being cost effective is provided.

Magnetic coupling, according to the invention, can be used to provide a yarn brake and holding the carrier stationary for two-for-one twisting machines in particular.

BRIEF DESCRIPTION OF FIGURES

Preferred embodiments of the invention will now be described, by way of example only, and with reference to the accompanying drawings in which:

Figure 1 illustrates perspective view of the twisting machine according to the invention.

Figure 2 illustrates holding the carrier stationary and transmitting motion to yarn winding unit along with the other mechanisms in cross sectional view in accordance with the present invention.

Figure 3 illustrates the mechanism shown in Figure 2 in a simplified form.

Figure 4 illustrates the mechanism shown in Figure 2 and Figure 3 in perspective sectional view.

Figure 5 illustrates the upper body to which motion is transmitted in lower perspective view.

Figure 6 illustrates the lower body transmitting motion in an upper perspective view.

Figure 7 illustrates the polarity orientations of the lower magnets and the upper magnets forming axial magnetic coupling.

Figure 8 illustrates magnetic flux of carrier and magnet rings in a schematic view.

Figure 9 illustrates an alternative disc to the magnetic flux permeable disc in a perspective view.

Figure 10 illustrates polarity orientation of lower and upper magnets forming magnetic coupling and the elements disposed in the disc magnetic flux of the magnet rings in schematic view.

Figure 11 illustrates magnetic flux permeable ferrite-based elements disposed in the disc of Figure 9.

Figure 12 illustrates an alternative arrangement for magnetic flux permeable elements disposed in the disc of Figure 11.

Figure 13 illustrates an alternative arrangement for magnetic flux permeable elements disposed in the disc of Figure 11.

Figure 14 illustrates an alternative drive mechanism for driving main shaft and/or bobbin winding unit.

Figure 15 illustrates an alternative drive mechanism for driving bobbin winding unit.

Figure 16 illustrates an arrangement for electricity generation at the upper body of the machine.

Figure 17 illustrates the arrangement of Figure 16 in perspective view.

Figure 18 illustrates the components placed onto an upper platform of the machine.

Figure 19 illustrates axial magnetic coupling for use in two-for-one twisting machine.

DETAILED DESCRIPTION OF THE INVENTION

The twisting machine according to the invention is shown in Figure 1. According to the figure, functional body of the machine is connected to the chassis (22) via a main bearing (26). A motor (30) rotating a main shaft and a twisting disc connected thereto transmits its motion via a belt (24) and another motor (31) driving a bobbin winding unit, further details of which will be described below transmits its motion via a belt (25). Both motors (30, 31) are connected to the chassis through conventional fixing means.

Yarns (29) to be twisted are taken from the various number of bobbins (28) and directed to yam brake and then introduced into the main shaft (32). Yarn (10)

passing through a hole (3) formed in the reservoir (1) under the twisting disc (2) is introduced into guide hole (6) provided the upper side of a support member (11), and directed respectively to a yam guide (7) attached to support member (11), another yarn guide (12) after idle directing yarn feeder (8) and a driven yarn feeder (9) around which the yarn is sufficiently wound, the yarn is further directed to a waxing mechanism (13) and passed through a wax (14), the yarn is then proceed additional yarn guides (15, 16) and wound around yarn winding unit (4) for winding onto the bobbin (5).

Yarn winding process is achieved by winding the yarn onto the bobbin (5) via the winding unit (4) while the twisting disc is rotated and the yarn (10) is drawn by the yarn feeder (9) as the entire components associated with the carrier (2) are held stationary.

Upper platform (95) is connected to the carrier (21) via support rods (18). Driven yarn feeder (9) and the waxing mechanism (13) is driven by shaft (17) rotating synchronously with the winding unit (4).

Bobbin (5) is connected to the carrier (21) via an articulated bobbin support (19), and required compression onto the bobbin (5) is achieved via a spring (23) pressing onto the bobbin support (19).

In Figure 2 it is illustrated that holding the carrier stationary and transmitting motion to yarn winding unit along with the other mechanisms in cross sectional view in accordance with the present invention. According to the figure, main shaft rotatable around its axis (32) is mounted to the chassis (22) via ball bearings (26, 33). Main shaft (32) is driven by a motor (not shown in this figure) through a belt (24) over a belt housing formed on the shaft (32). The main shaft (32) includes a hole (98) extending along the axis thereof, through which yarn is fed from a lower opening (96), and this hole (98) is running along a flange (42) coaxially mounted to the main shaft (32). Shaft hole (98) is oriented in radially outer direction of the reservoir (1).

A disc (40) being coaxial to the main shaft (32) is provided on the outer surface of the flange (42). The disc (40) is electrically non-conductive and non-magnetic, and formed preferably from a composite material for providing sufficient rigidity and strength. A hole (48) is formed radially outwardly of the disc (40) for proceeding the yarn therein. As the disc (40) is non-conductive and non-magnetic, magnetic flux through the disc (40) is not lost in a form of eddy or hysterisis flow, therefore this mechanism based on a magnetic coupling is prevented from both energy and force losses.

A stationary magnet ring (35) is connected to the bearing (26, 33) connected to the chassis (22). A plurality of magnets (37) is disposed on the stationary magnet ring (35), the magnets (37) being distributed evenly around the axis of the shaft in a manner that one north poled magnet is placed next to one south poled magnet.

Similarly a lower drive ring (34) mounted to the upper side of the is provided to the fixed bearing (33) via a ball bearing and this ring (34) is rotatable around the ball bearing. The ring (34) is driven by a belt (25) trained on the belt grooves and connected to the motor. A plurality of magnets (36) is disposed on the lower drive ring (34), the magnets (36) being distributed evenly around the axis of the shaft in a manner that one north poled magnet is placed next to one south poled magnet.

According to the preferred embodiment of the invention, the drive ring (34) and the magnets (36) associated thereto are closer to the shaft axis than the stationary magnet ring (35) and the magnets (37) associated thereto, however the positions of the rings and the respective magnets can be changed in an alternative configuration of the machine.

Bobbin winding unit (4) and the carrier (21) are mounted on to the main shaft (32) via a rulman bearing (45).

An upper stationary magnet ring (43) is fixed to the carrier (21) in a manner that the ring (43) corresponds to an upper position of the lower stationary ring (35). Similar to the lower stationary magnet ring (35), a plurality of magnets (39) is disposed on the upper stationary magnet ring (43), the magnets (39) being distributed evenly around the axis of the shaft in a manner that one north poled magnet is placed next to one south poled magnet. The diameter of the upper magnet ring (43) and as well as the features, numbers and positions of the magnets of the upper magnet ring (43) are preferably identical with those of the lower stationary magnet ring (35).

An upper drive ring (44) is provided in a manner that the ring (44) corresponds to an upper position of the lower drive ring (34), and the ring (44) is rotatable around a ball bearing mounted to the shaft (32). Similar to the lower drive ring (34), a plurality of magnets (38) is disposed on the upper drive ring (44), the magnets (38) being distributed evenly around the axis of the shaft in a manner that one north poled magnet is placed next to one south poled magnet. The diameter of the upper drive ring (44) and as well as the features, numbers and positions of the magnets of the upper drive ring (44) are preferably identical with those of the lower drive ring (34).

The distance between the magnets designated 36 and 38; and 37 and 39 disposed to the rings (34, 35, 43, 44) is sufficient to allow adequate magnetic force between these magnets. The disc (40) is provided between the magnets (36, 38; 37, 39).

The lower stationary magnet ring (35) and the respective magnets (37) together with the upper stationary magnet ring (43) and the respective magnets (39) form a magnetic coupling. As the lower stationary magnet ring (35) is fixed to the chassis (22) the respective magnets (37) are immovable and through magnetic force between the lower and upper magnets (37, 39) the upper stationary magnet ring (43) becomes immovable, therefore the carrier (21) placed onto the rotating shaft (32) via ball bearings can also be held immovable.

Similarly, the lower drive ring (34) and the respective magnets (36) together with the upper drive ring (44) and the respective magnets (38) form a magnetic coupling. As the lower drive ring (34) is rotated the upper drive ring (44) rotates via the magnetic forces therebetween, and power transmission to drive the mechanisms on the carrier (21) is provided via a belt (49) over the upper drive ring (44).

In Figure 3 the machine is shown in a simplified cross section view to better identify the stationary and movable components. In this figure, the section 56 designates the components 22, 26, 33, 35; section 57 designates the components 21, 45, and 43; and section 55 designates the components 32, 1, 2, 3, 40, 41 , 42 and 48. These sections 55, 56, and 57 will be used to refer for the future drawings.

The upper drive ring (44) driven by the lower drive ring (34) through the axial magnetic coupling, drives an intermediate pulley (47) through a belt (49) and the motion is further transmitted to a pulley (46) driving the upper mechanisms. The bobbin winding unit (4) mounted to the carrier via a support (20) and achieving winding of the twisted yarn (10) on to the bobbin (5) is driven by the intermediate pulley (47) via a belt (50). The belt (50) is trained on rollers (51) changing the direction of the belt (50). The motion transmission from the upper drive ring (44) to the bobbin winding unit (4) is achieved preferably via a belt pulley mechanism.

In Figure 5 the upper body to which motion is transmitted is shown in lower perspective view. The group of magnets (39) providing the carrier being held stationary and the group of magnets (38) providing the drive force to the bobbin winding unit (4) are clearly shown in this figure.

In Figure 6 the lower body transmitting motion to the upper body is shown in an upper perspective view. The group of magnets (37) forming a magnetic coupling with the group of magnets (39) providing the carrier being held stationary and the group of magnets (36) forming a magnetic coupling with the group of magnets (38) providing the drive force to the bobbin winding unit are clearly shown.

In a preferred embodiment of the invention, anti-magnetic protective discs (63, 60, 64, 61) are provided to keep the magnets (37, 38, 39, 36) in their positions where the magnets are mounted.

In Figure 7, polarity orientations of the lower magnets (37, 36) and the upper magnets (39, 38) forming magnetic couplings, and in Figure 8 the magnetic flux of the disc (40) and magnet rings (35, 34, 43, 44) is shown schematically.

In Figure 9 an alternative disc to the magnetic flux permeable disc in a perspective view. Effective magnetic fields of magnets decreases as the distance increases therebetween, therefore the magnetic flux amplitude between the magnets decreases as the thickness of the disc increases, which leads to a decrease in torque transmission. Through the alternative disc (40) shown in Figure 9, magnetic flux between the magnets, so the torque transmitted can be increased by use of a relatively thick disc.

Magnetic elements (65) the electricity conduction of which in radial direction is limited are disposed in the disc (40) with a certain space therebetween, the disc being electrically non-conductive and non-magnetic. The elements (65) are positioned between the magnets to correspond to them and the number of the magnetic elements (65) is independent of the number of magnets.

In Figure 10 polarity orientations of the lower magnets (37, 36) and the upper magnets (39, 38) forming magnetic couplings, and the magnetic flux of the elements (65) in the disc (40) and magnet rings (35, 34, 43, 44) is shown schematically.

The elements (65) can be formed to have various type of geometry, but preferably formed as small cylinders for the ease of production.

The elements, as shown in Figure 11 , can be ferrite having iron atoms therein or the elements can be covered by electrically isolated sintered iron powders or, as seen in Figure 12, the elements can comprises wires having electrically isolated

thin irons or as seen in Figure 13, the elements can comprise thin sheets the edges of which are electrically isolated and the sheets having irons are concentrically disposed one another and being spiral, continuous or discontinuous.

According to an alternative embodiment of the invention, in Figure 14, an arrangement is shown for independently driving of the main shaft (32) and the bobbin winding unit (4).

The external motor (30) and the belt (24) disclosed above for the preferred embodiment of the invention, are eliminated in this alternative embodiment and the shaft (32) rotating twisting disc (2) can be directly driven through providing a rotor (73), being coaxial to the shaft (32), and a stator (72) surrounding the rotor (73) and mounted to the stationary part (56) of the lower chassis (22) of the machine.

Similarly, the external motor (31) and the belt (25) disclosed above for the preferred embodiment of the invention, are eliminated in this alternative embodiment, drive ring (34) so the bobbin winding unit (4) can be directly driven through providing a rotor (70), being coaxial to the ring (34), and a stator (71) surrounding the rotor (70) and mounted to the stationary part (56) of the lower chassis (22) of the machine.

With this alternative configuration, a more compact construction can be achieved and losses due to external motors (30, 31) and belts (24, 25) can be prevented.

In Figure 15, an alternative mechanism is shown for driving the bobbin winding unit (4). According to the figure, the external motor (31), the belt (25) and the lower drive ring (34) disclosed above for the preferred embodiment of the invention, are eliminated in this alternative embodiment and a stator (74) capable of forming a rotatable magnetic field is mounted to the stationary part (56). Magnets (36) at the upper side of the lower drive ring (34) are also eliminated in this alternative.

An embodiment for generating electricity at the upper body of the machine is shown in Figure 16 and a perspective view of position of the generator is shown in

Figure 17. According to the figure, A generator (80) driven by the main shaft (32) is mounted to the upper chassis (57). A generator rotor (97) having magnets /90) thereon is connected to the upper side of the shaft (32). A stator (88) and coils (89) thereof being communicated with the rotor (97) are mounted to the upper chassis (57) of the machine. Electricity generated by the generator is conditioned by the electronic circuits and then served to be used. In a preferred embodiment of the machine the rotor (97) used has fixed magnets (90), however a coiled rotor can equally be utilized as desired.

Therefore, through a linear motor (84) or a rotary motor the motion of which is converted to a linear motion, the yarn passed over a yarn guide (85) connected to a linear motion mechanism is wound on to the bobbin (5) at an angle desired. Furthermore, as the upper chassis (57) inside the balloon (10) can be electrified, the machine can also be used in yarns spinning systems in addition to yarn twisting.

By means of the generator (80) capable of generating sufficient power, the bobbin driving motor (31) and components operating with this motor (31) including for example magnet rings (34, 44), intermediate pulley (47) will not be required, and drive power of various components including yarn guide (85), bobbin (5), yarn feeder (9), waxing mechanism (13) and other components that would be incorporated like yarn brake, bobbin compression mechanisms and other possible components can be provided by the electricity generated by the generator.

A sensor (82) is provided to external control of the electrically operated components of upper chassis (57). The sensor (82) is an optic or RF sensor capable of transmitting and receiving signals and providing a communication with the electronic circuits (81) placed inside of the balloon. This sensor (81) is in communication with another sensor (83) placed outside of the balloon (10). The outer sensor (83) transmits its signals received from a controller to the sensor (82) and the signals received from the internal sensor (82) to the controller.

In Figure 18, the components on the upper platform (95) are shown. The pulley (46) driven by a belt (49) (see Figure 2) is connected to a shaft (17) transmitting

motion to the components on to the upper platform (95). The yarn feeder (9) feeding the twisted yarn to the bobbin winding unit (4) is driven by a pulley (91) connected to the shaft (17) and a belt (94) trained to the pulley (91). An auxiliary yarn feeder (8) is driven by yarn (10) trained thereon. The wax (14) waxing the twisted yarn is driven by an upper auxiliary pulley (92) and a belt (93).

The twisted machine according to the invention can be used for yarn braking in a two-for-one machine. A figure of this arrangement is given in Figure 19. According to the figure, for two-for-one twisting, the yarn unwound from the bobbin (28) being on to the stationary carrier is directed downwardly through the hole (100) of the bobbin (28) and then directed upwardly over the twisting disc (2) driven by the main shaft (32) to form the yarn balloon. The lower drive ring (34) to which magnets (36) are disposed radially to the shaft (32) axis is associated with a gear (102) to which a drive lever is connected via a trigger belt (101). As the drive lever (103) is rotated magnets (36) rotates and so corresponding magnets (38) forming an axial magnetic coupling with the magnets (36) also rotates and consequently this rotates the upper drive ring (44) to which the corresponding magnets (38) are connected.

The upper drive ring (44) is associated to a gear (104) to drive thereof and the gear (104) transmits its motion to a cam (106) via a shaft (105) connected thereto. The cam (106) drives a follower (109) displacing in axial direction thereof and the follower (109) connects to a spring (108) the other end of which connects to a yarn brake (107) moving in axial direction.

The end of the yarn brake (107) moves the yarn flowing downwards through the bobbin hole (100) towards the wall of the hole to squeeze thereof to provide a yarn brake.

As disclosed for the above arrangements, holding the carrier (21) stationary is provided by forming magnetic coupling between the lower and upper magnet groups (37, 39).