Present invention relates to a traverse device that may be used on yarn winding machines, as a linear motor and other machines in which traverse mechanisms are useful.
While necessary yarn carrying force of a traverse mechanism of a yarn winder should be very low, speed of winding must be very high, uniform and controlled for production considerations, and traverse mechanisms should have quickest return in a short distance for the quality of yarn packages.
The reciprocating motion in high speeds, with a quick return, in short distances complicates the process, requiring excellent control of the speed of such traverse motion.
There are several design aspects that may be considered to be improved of the characteristics of a traverse device to provide a better and faster traverse motion that may be used in mechanisms for winding of yarn on a support element.
Not having turning members and not requiring driving several related members, such linear motors for direct traversing systems also provide significant advantage in terms of force/weight ratio and for long term operation.
Directly and electrically driven traverse devices that may be used for winding yarn onto a support element can be diversified with different aspects.
The first diversification is the type of the moving element or cursor which can be a coil or magnet fixed to on it which the yarn carrying assembly is mounted.
The moving coil type of linear motor requires that coils be moved, whereas the stator is consisting permanent magnets. The cables for powering the coils have to be moving in this design, which is not suitable for long term operation due to the fatigue of the cables that occur by frequent reciprocating motion. Thus, it is obviously more advantageous to use the moving magnet type traverse device for winding yarn onto a support element. Traverse devices with moving magnets not having moving coils and cables are obviously more reliable and advantageous for long term operation.
The second diversification is about the magnetic forces on the moving element of the traverse device.
Coil and/or magnet and/or core interactions in a traverse device create forces to run the device. In general, these forces have parallel and orthogonal components. While the parallel component is the useful force to move the moving element, the orthogonal component provides attracting force between stator and the moving element. The presence of orthogonal forces requires robust bearing system such as rollers and bearings to overcome the serious attracting forces. These mechanical components obviously increase the weight of the moving element, thus it will consume more energy during traversing and limit the acceleration performance of the system. Thus, it is obviously more advantageous to use the traverse device with balanced orthogonal forces for winding yarn onto a support element.
The third diversification is the shape of the traverse device.
There are known moving magnet traverse devices with cylindrical shape having rod shaped moving element, like piston. In this device, coils are fixed, whereas the rod consisting of permanent magnets is moved. Tubular motors comprise permanent magnets in cylindrical form to be moved reciprocally. Therefore, yarn guides are placed at ends of the cylindrical tube of permanent magnets.
Tubular traverse devices of these kind are however disadvantageous in their use for yarn winding, since the presence of the cylinder actuator and its lateral bulk would prevent the winding heads being placed side by side, as is often the case on textile machines. In addition, even if the moving masses are reduced, they still remain high since the tube magnet or its connected arm must have at least the length of the winding travel plus a sufficient length that remains within the body of the cylinder actuator in order to take the magnetic forces. Thus, it is obviously more advantageous to use the traverse device without a rod shaped moving element.
The fourth diversification is the structure of the cores of the traverse device.
Traverse devices can be constructed as slotted or slotless core types. The slotted types have extensions of the magnetic cores at periodical distances along the length of linear motor. In these types of devices the coils are wound in such a position to magnetize the slots which are interacting with the magnets. Manufacturing of slotted magnetic cores and the windings in these kinds of traverse devices are more complex than slotless type.
Slotless design reduces the total size of the motor considerably, allowing manufacturing more compact motors, reducing complexity of the other parts, providing less complicated manufacturing, having better heat transfer performance through the placement of coils and allowing higher speeds. Slotless design also eliminates the undesired cogging forces and decreases iron losses.
Thus, it is obviously more advantageous to use the traverse device with slotless structure.
The fifth diversification is the driving method of the traverse device.
Since traverse devices used in a yarn winding system need a moving magnet, the stator must consist of coils and magnetic core. Considering the mass of the moving element, which should be as low as possible for energy saving, only the necessary coils should be energized on necessary places during the motion of the moving element. Allocating the energy to different coils will need many electronic components to be employed. Reduction of the number of phases to drive the coils simplifies the allocation process. Thus, it is obviously more advantageous to use the traverse device with two phases.
The sixth diversification is the ratio of the number of moving magnets continuously having force interactions with the coils.
Since in a traverse device magnetic interactions of coil, magnet and core create forces to run the device, in some designs only the particular moving magnets or magnet poles may be under force interactions while the others not at a particular time. To achieve the necessary force to obtain the required speed and acceleration, it is needed to increase the number of magnets or magnet poles, which results increase in size and weight of the moving element. Thus, it is obviously more advantageous the traverse device which all the magnets in moving elements are always in force interaction.
JP 8217332 discloses a device with a magnet which is related to a yarn guide to act, a guide member to guide the magnet to be capable of reciprocation, and magnetic force generating means to generate strong magnetic force of the same pole as a magnetic pole of the magnet on the facing side when the magnet reaches a position as each end part of a traverse section of the yarn guide. It may also be provided with electromagnets to reciprocate the magnet for integrally controlling reciprocation of the magnet by the reciprocation magnets and turning by the magnetic force generating means.
JP 7137934 discloses an arrangement having a stator yoke fixed thereto with a permanent magnet and a center yoke inserted therein with a core (reciprocating runner) which is therefore axially movable and which incorporates a flange attached to a yarn guide receiver, are fixed to a side yoke in parallel with each other. In this arrangement, sensors are provided at positions inside of turn-back ends of the reciprocating stroke of the core so as to detect passing of the core. With this arrangement, when a predetermined time elapses, the core is stopped so as to reverse the running direction of the core. With this arrangement in which the core is surely turned back at the turn-back positions, a yarn can be traversed at a high speed. That is, the time to be set on the timer can be suitably selected.
One object of the present invention is to provide a traverse device that may be used on winding machines, as a linear motor, and other machines in which traverse mechanisms are useful, which is more efficient and faster and reliable.
The object aimed is achieved by a traverse device, suitable for particularly winding yarns, comprising a longitudinally extending stator having a ferromagnetic core material provided with coil members; a moving element having permanent magnets forced by the coil members and moved along the longitudinal direction of the stator. The traverse device of the invention is characterized in that a moving element co-axially provided outside the coil members which surround the ferromagnetic core material; each coil member comprising a number of winding units in a manner that the current to flow in clockwise direction while in the next winding of the same phase to flow in counterclockwise; and winding units of each coil member being spaced apart from one another allowing the winding units of the other coil member can be placed within respective spaces.
According to a preferred embodiment of the invention, ferromagnetic core material, coil members and moving element can be of cylindrical, rectangular/square or any polygonal profiled form.
Another embodiment of the traverse device of the invention, comprises a moving element provided between two stators having the coil members which surround the ferromagnetic core material; each coil member comprising a number of winding units in a manner that the current to flow in clockwise direction while in the next winding of the same phase to flow in counterclockwise; and winding units of each coil member being spaced apart from one another allowing the winding units of the other coil member can be placed within respective spaces.
Another embodiment of the traverse device of the invention, comprises a moving element provided between two stators having the coil members which are provided outwardly at least on one side of ferromagnetic core material; each coil member comprising a number of winding units in a manner that the current to flow in clockwise direction while in the next winding of the same phase to flow in counterclockwise; and winding units of each coil member being spaced apart from one another allowing the winding units of the other coil member can be placed within respective spaces.
The present invention is to be evaluated together with annexed Figures briefly described hereunder to make clear the subject embodiment and the advantages thereof.
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As seen in
Coil members (2,3) encircle the ferromagnetic core material (4) entirely. A yarn guide (14) is provided to the moving element (6) to guide yarns to be wound onto a support member.
As seen in
The force required to move the permanent magnets (8) is achieved by moving the magnetic field, which is created by shifting phase of current flow over the coil members 113 (2,3) for a two phase drive configuration: Namely, the first coil member (2) is energized in phase A (11) and the second coil member (3) is energized in phase B (12) such a manner that the current flows alternating with 90 degrees of phase shift. Currents on each coil member (2,3) are shown in
This arrangement is also magnetically balanced, as the sum of orthogonal forces applied on the moving element (6), in respect of the axis of the core material (4), will be zero.
While the number of magnets (8) of the moving element (6) can be selected independently, the inventor has surprisingly found that the most effective outcomes are achieved when the magnets (8) with three opposing polarities along the axis. This applies to other embodiments to be detailed below.
As seen in
Each rectangular prism shaped magnet (8) is oppositely poled from inwards to outwards, and the polarity is reversed with respect to the next one along the axis, i.e. if the first magnet is poled N-S from inwards to outwards, the next magnet in axial direction is poled S-N from inwards to outwards. A flat multi-poled single magnet can also be used alternatively. The magnets (8) are preferably placed all of the sides of the coil members (2,3).
As seen in
Another embodiment of the traverse device (1) is shown in
As seen in
As seen in
Another embodiment of the traverse device is shown in
In
As seen in
Another embodiment of the traverse device is shown in
The effect of this configuration on flux flow can be seen from
All embodiments above define magnetically balanced structures in that orthogonal components of forces occurred between the magnets (8) and the coil members (2,3) while the magnets (8) are moved, and allowing parallel components of these forces to remain, which are useful to move the magnets (8) longitudinally. Further, the embodiments above, all comprise slotless type coil members (2,3) with two phase drive configuration, which provides achievement of considerably higher forces to move the magnets (8) without saturating ferromagnetic core (4) magnetically. The number of magnets (8) used in the moving element (6) of all the embodiments above can be of any number, such as single magnet with single or multiple polarities on each side, or multiple magnets with single or multiple polarities on each side.
As the moving element (6) of the traverse device should move along the axis and the coil members (2,3) which are essentially placed as covering the whole path of motion, only the currents flowing in some portion of winding units (10) contribute the linear motion of the moving element (6). This means that useful winding units (10), in this respect, are those, which are just interacting with the moving element (6) at a particular position. Energizing the rest of the winding units (10), which do not contribute to the motion of the moving element (6) would obviously result energy waste.
For this reason, it is necessary to energize a particular winding unit at a time, corresponding to the location of moving element (6) along the motion path, continuously during the motion.
As seen from
This invention proposes three separate arrangements to control the supplying of energy for winding units (10) and supplying the current to desired direction at desired level to perform the continuous motion of magnets (8).
The first embodiment uses unidirectional electronic switching elements such as mosfets, IGBTs or transistors.
As shown in
A controller (17) controls the necessary current level of any phase by means of an adjustable unipolar current controller (18) which may be preferably a PWM controller.
The high side transistors (MH1, MH2, MH3, MH4, MH5, . . . ), being preferably of Mosfet-type, are placed between the series connections of individual winding members (W1, W2, W3, W4, W5, . . . ) and the power line connected to the positive terminal of adjustable unipolar current controller (18). The actuation of these transistors (MH1, MH2, MH3, MH4, MH5, . . . ) are performed by the high side transistor driving circuit (19), which is commanded by the same controller (17). Similarly the low side transistors (ML1, ML2, ML3, ML4, ML5, . . . ), being preferably of Mosfet-type, are placed between the series connections of individual winding members (W1, W2, W3, W4, W5 . . . ) and the power line connected to the negative terminal of adjustable unipolar current controller (18). The actuation of these transistors (ML1, ML2, ML3, ML4, ML5, . . . ) are performed by the low side transistor driving circuit (20), which is commanded by the same controller (17).
This embodiment gives the freedom to activate any number of neighboring winding units (W1, W2, W3, W4, W5 . . . ) at a time by activating the required high side transistor (ML1, ML2, ML3, ML4, ML5, . . . ) and activating the required low side transistor (ML1, ML2, ML3, ML4, ML5, . . . ) at a time
For example, if winding members, say (W5) and (W6), are needed to be energized in such a way that the current is flowing through from winding member (W5) to winding member (W6), the high side transistor (MH5) and the low side transistor (ML7) are activated. Similarly, if the winding members (W5) and (W6) is needed to be energized in such a way that the current is flowing through from winding member (W6) to winding member (W5), i.e. the opposite direction of the above current flow, the high side transistor (MH7) and the low side transistor (ML5) are activated.
Bidirectional electronic switching elements such as Triacs, solid state relays are used for the second embodiment.
As shown in
In this embodiment, the controller (17) controls the necessary current level and current direction of any phase by means of an adjustable bipolar current controller (22) which can be preferably an H-Bridge PWM controller.
The bidirectional electronic switching elements (TS1, TS2, TS3, TS4, TS5, . . . ), being preferably of Triac-type, are placed between the series connections of individual winding members (W1, W2, W3, W4, W5 . . . ) and the power lines connected to the terminals adjustable bipolar current controller (22) alternately as one of them is connected to first line, the second one is connected to second line and the next one is connected to first line again. The actuation of these Triacs (TS1, TS2, TS3, TS4, TS5, . . . ) are performed by Triac driving circuits (23, 24) which are commanded by the same controller (17).
This embodiment gives the freedom to activate any number of neighboring winding units (W1, W2, W3, W4, W5, . . . ) at a time by activating the required Triacs (TS1, TS3, TS5 . . . ) connected to first power line of adjustable bipolar current controller (22) and activating the required Triacs (TS1, TS3, TS5 . . . ) connected to second power line at a time.
This configuration allows energizing the winding members (W1, W2, W3, W4, W5, . . . ) as serial connection, if the required number of energized winding unit is odd, such as 1,3,5 etc. This configuration allows energizing the winding members (W1, W2, W3, W4, W5, . . . ) as parallel, if the required number of energized winding unit is 2.
For example, if only 3 winding members, say (W5), (W6) and (W7), are needed to be energized, the Triac (TS5) connected to the first line and Triac (TS8) connected to the second line are activated. As can be understood from the
If, for example, only 2 winding members, say (W5) and (W6), are needed to be energized, the Triacs (TS5) and (TS7) connected to the first line and Triac (TS6) connected to the second line are activated. As can be understood from the
The third embodiment also uses bidirectional electronic switching elements such as Triacs, solid state relays.
As shown in
The controller (17) controls the necessary current level and current direction of any phase by means of the adjustable bipolar current controller (22) which can be preferably an H-Bridge PWM, controller.
The bidirectional electronic switching elements (TD1, TD2, TD3, TD4, TD5, . . . ), being preferably of Triac-types, are placed between the series connections of individual winding members (W1, W2, W3, W4, W5 . . . ) and the power lines connected to the terminals adjustable bipolar current controller (22) alternately as two adjacent ones are connected to first line, the two adjacent ones are connected to the second line and the next two adjacent ones are connected to first line again. Actuations of these Triacs (TD1, TD2, TD3, TD4, TD5 . . . ) are performed by the Triac driving circuits (23, 24) which are commanded by the same controller (17).
This embodiment gives the possibility to activate the two of the neighboring winding units (W1, W2, W3, W4, W5 . . . ) at a time by activating the required Triacs (TD1, TD2, TD5 . . . ) connected to the first power line of the adjustable bipolar current controller (22) and activating the required Triacs (TD3, TD4, TD7 . . . ) connected to the second power line at a time.
This configuration allows energizing the winding members (W1, W2, W3, W4, W5 . . . ) as series connection if the required number of energized winding unit is 2.
For example, if two winding members, say (W5), and (W6), are needed to be energized, Triac (TD5) connected to the first line and Triac (TD7) connected to the second line are activated. As can be understood from the
Adjustable unipolar and bipolar current controllers (18 and 22) provide the control of the traverse length, and the speed and the position of the moving element (6), which enhances the versatility of the instant traverse device.
A traverse device essentially needs precise position and speed control. Also the commutation of the coil members (2,3) essentially needs the position feedback. For this reason four different position feedback units are proposed with this invention.
In the first embodiment, as in
In the second embodiment, as in
In the third embodiment, as in
In the fourth embodiment, as in
Reciprocating motion of a traverse device requires that a moving element continuously accelerate and decelerate along the device. Namely, accelerating from an end towards the middle point of the device, and decelerating from the middle point towards the other end of the device. Such continuous deceleration and acceleration motions of the moving element, in relatively short distances, requires considerable electric current to be applied to the coil members (2,3), which inevitably increases the power consumption. An arrangement which can store the kinetic energy of the moving element (6) during deceleration and give back the stored energy during acceleration would obviously increase the performance of the traverse device (1) and reduces the power consumption.
Such a kinetic energy storage arrangement may be mechanical springs (37) that can be provided at both ends of the traverse device (1), or in more generic terms, the springs (37) are provided at the required reversing points of the moving element (6). The springs (37) are supported by stationary elements (36) at their ends. In use, the moving element (6) will hit to the spring (37) at the required position of turning point, providing the spring member (37) to absorb the kinetic energy of the moving element (6) as a potential energy. As soon as the moving element (6) stops its motion due to the spring's (37) reaction, the spring (37) will give its stored energy to the moving element (6) in the opposite direction. Therefore, the moving element (6) will move back without major loss of its kinetic energy. Position of the springs (37) may be displaced on the traverse device (1) or the length of the springs (37) may be increased or decreased manually or automatically by a proper drive mechanism in compliance with the length of the stroke of the moving element (6).
Numerous of alternative spring means can be equally adapted replacing the mechanical spring (37) or in combination with the spring (37). For example magnets (38), (39) can be provided to both ends of the moving element (6) and to the stationary elements (36) of the traverse device (1) with opposite polarity. The oppositely poled magnets (38,39) would then function as a “spring member” once these magnets approach to each other. Alternatively, a combination of a spring and magnets can be arranged for creating spring effect. Such a combination is seen in
Another arrangement providing a spring effect may include suitably shaped members of some rubber-like material, or a pneumatic piston type member which accumulates potential energy as the moving element (6) pressures the piston and gives this energy back to the moving element (6) in opposite direction.
The spring effect may be provided by any combination of the above spring members or means.
Another arrangement providing a spring effect may comprise oppositely poled magnets (44) provided on the ferromagnetic core, at the required reversing points of the moving element (6), as seen in
The coil members (2,3) require the winding of a conductor in a manner that the current flow as a loop to produce magnetic flux in the core material (4). The coil members (2,3) of a traverse device (1) are representatively shown in
As in
The foil (41) and film (42) combination (40) may be produced by a number of ways, similar to producing conventional PCBs such as chemical etching of conductor foil (41) which is already laminated on the electrically insulating backing film layers (42). Both ends of the coil members (2,3) are connected to each other as required to provide the necessary current flow and energizing them through terminals (43).
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/TR10/00079 | 4/12/2010 | WO | 00 | 10/11/2012 |