Abstract:
The present invention concerns forming wire coils by simultaneously winding a plurality of wires onto a dynamo-electric machine component. In order to maximize the amount of wire that can be placed in the spacings of the dynamo-electric machine component, the turns of the wire coil must be regularly disposed without twisting the plurality of wires onto each other. Current winding apparatus may allow certain portions of the wire turns to unevenly accumulate and locally bulge outward from the collection of wire coils. Such bulges, especially in consideration of the limited spacings available on an dynamo-electric machine component, may interfere with or access to the spacings by a wire dispensing member during the winding process. The present invention proposes to perform multiple-wire winding processes that avoid wire twisting and improper disposition of the wires. Further, the present invention proposes to improve the ability of the wire dispensing member to traverse the spacings on the component. As a consequence, the winding processes performed with the present invention are less likely to be hindered by interference and are capable of obtaining more wire fill within the component spacings and higher winding speeds.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]    This application claims the benefit of priority from U.S. provisional patent application No. 60/432,392, filed Dec. 9, 2002, which is hereby incorporated by reference herein in its entirety. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention concerns solutions for winding coils of wire onto dynamo-electric machine components. In particular, the present invention concerns forming wire coils by simultaneously winding a plurality of wires onto the dynamo-electric machine component. For example, wire coils may be wound onto the poles of a lamination core or may be wound onto themselves in components that do not require or possess poles.  
           [0003]    These wire coils have the purpose of generating the electromagnetic field needed in the final application of the dynamo-electric machine component. For example, the previously mentioned lamination core may be either a stator core or an armature core of a dynamo-electric machine. The dynamo-electric machine as a whole may be an electric motor, which is used for many types of driving applications.  
           [0004]    In order to maximize the amount of wire that can be placed in the spacings of the dynamo-electric machine component, the turns of the wire coil must be regularly disposed (e.g., along the sides of the pole pieces) without twisting the plurality of wires onto each other. Further, the wires must be placed so that the wire turns are positioned in an ascending or descending layer formation (commonly referred to in the art and hereinafter as “stratification”).  
           [0005]    Current winding apparatus may allow certain portions of the wire turns to unevenly accumulate and locally bulge outward from the side of the collection of wire coils. Such bulges, especially in consideration of the limited spacings available on an dynamo-electric machine component, may interfere with or impede access through the limited component spacings during the wire winding process.  
           [0006]    This situation is even more severe when the winding process requires the simultaneous winding of a plurality of wires to form a single wire coil, especially when the wire dispensing member must pass through the spacings on the dynamo-electric machine component to wind the multiple wires. As a result of the requirement for multiple wires, bulges are more likely to be caused by twisting of the multiple wires and may interfere with the movement of the wire dispensing member within the component spacings.  
           [0007]    The present invention proposes to perform multiple-wire winding processes that avoid wire twisting and improper disposition of the wires. Further, the present invention proposes to improve the ability of the wire dispensing member to traverse the spacings on the dynamo-electric machine component. As a consequence, the winding processes performed with the present invention are less likely to be hindered by interference and are capable of obtaining more wire fill within the component spacings and higher winding speeds.  
           [0008]    These and other objects of the present invention will be more apparent in view of the following drawings and detailed description of the preferred embodiments. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    Non-limiting embodiments of the present invention are described hereinafter with reference to the accompanying drawings in which:  
         [0010]    [0010]FIG. 1 is an elevational partial view of a wound stator core as seen from an axial end thereof;  
         [0011]    [0011]FIG. 2 is a partial sectional view of the stator core showing certain parts of the apparatus of the present invention as seen from direction  2  of FIG. 1;  
         [0012]    [0012]FIG. 3 is a partial sectional view of the apparatus taken from line  3 - 3  of FIG. 2;  
         [0013]    [0013]FIG. 4 is a partial sectional view similar to FIG. 3 that shows the apparatus of the present invention disposed to the left of the apparatus shown in FIG. 3; and  
         [0014]    [0014]FIG. 5 is a schematic view showing the overall apparatus of the invention as seen from view lines  5 - 5  of FIG. 2.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0015]    The solutions of the present application are generally related to those described in commonly assigned Stratico et al. U.S. Pat. No. 6,622,955 which is incorporated by reference herein in its entirety.  
         [0016]    With reference to FIG. 1, stator core  10  has hollow cylindrical interior  11  centered on longitudinal axis  12 . Interior  11  is delimited externally by pole pieces  13 , which stem from annular portion  14  of the stator core. Expansions  13 ′ of pole pieces  13  are usually the innermost portions of stator core  10  and delimit the spacing of interior  11 . Gaps  16  existing between adjacent expansions  13 ′ are access passages which allow communication between interior  11  and slot spacings  15 . In the case of the stator core shown, gaps  16  and slot spacings  15  are inclined by a predetermined angle with respect to central axis  12 .  
         [0017]    Modern stator cores need to be compact in size. At the same time, the stator cores must maintain a significant quantity of ferromagnetic material and therefore a high wire presence within slot spacings  15 . As a result, gaps  16  are narrower and spacings  15  are even more full of wire as compared to prior stator cores. In addition, the electrical scheme of the stator cores is usually such that each coil C is wound around a single pole, like one of pole pieces  13  shown in FIG. 1. With reference to FIG. 1, coils C have been shown sectioned. For sake of clarity, portions of coils C which are outside the stator core have not been shown.  
         [0018]    The embodiment which is illustrated in the present application is directed toward the simultaneous winding of three wires around the poles of a stator core. However, it should be understood that any number of wires may be simultaneously wound in accordance with the present invention. It should also be understood that although the following description concentrates on an embodiment in which the wire coils are wound around a single pole, the present invention may be used to wind a wire coil through multiple poles. Similarly, the present invention may be used to wind wire coils around virtual poles in which no physical pole exists on the stator core. In the case of a virtual pole, wire coils are wound around each other about a theoretical pole axis on the stator. This type of stator may allow even more wire coils to be placed within a set amount of space in the core and are fully contemplated by the present invention.  
         [0019]    With reference to FIG. 2, wire nozzle  20  is shown in various relative consecutive positions P 1 -P 8 , which the wire nozzle occupy when moving around pole piece  13  to simultaneously dispense wires W 1 , W 2 , and W 3 . More particularly, by relative movements of wire nozzle  20  around pole piece  13 , wires W 1 , W 2 , and W 3  are simultaneously dispensed from respective wire exits  21 ,  22 , and  23  of wire nozzle  20  to become tensioned against pole piece  13 .  
         [0020]    Positioning of wire nozzle  20  in positions P 1 -P 8  can be achieved by relative movements between stator core  10  and wire nozzle  20 . For example, stator core  10  and wire nozzle  20  can be rotated with relative rotation R 1  when wire nozzle  20  is beyond end  10 ′ of stator core  10 . Oppositely, relative rotation R 2  may be provided when wire nozzle  20  is beyond end  10 ″ of stator core  10 . Rotations R 1  and R 2  are both substantially about central axis  12  of stator core  10 .  
         [0021]    Between these rotations, and even during the rotations, stator core  10  and wire nozzle  20  may be relatively translated in directions T 1  and T 2 , which are substantially parallel to central axis  12  of stator core  10 . For sake of clarity, FIG. 2 does not show the various positions of the stator core  10  as it is moved with relation to a stationary wire nozzle  20 . Instead, FIG. 2 shows the positions of wire nozzle  20  in the first plane (the plane of FIG. 2) as it accomplishes relative translations T 1  and T 2  and relative rotations R 1  and R 2  while stator core  10  is stationary. However, it should be understood that rotations R 1  and R 2  and translations T 1  and T 2  are strictly relative between wire nozzle  20  and stator  10 . Either nozzle  20  or stator  10  may be moved in order to accomplish this relative movement. It will also be useful in the following to define an instantaneous relative trajectory (or direction of movement) of wire nozzle  20  with respect to the relative movement between nozzle  20  and stator core  10 . This instantaneous relative trajectory (or direction of movement) of wire nozzle  20  should be understood to be the instantaneous direction of movement of wire nozzle  20 , as a result of the relative movement between nozzle  20  and stator  10 , seen from a frame of reference in which stator  10  is held fixed.  
         [0022]    It should be understood that rotations R 1  and R 2  may be sequenced and combined with translations T 1  and T 2  to accomplishes closed path  17  of wire nozzle  20  around pole piece  13 . A single closed path  17  may wind one turn of wire coil C with wires W 1 , W 2 , and W 3  around pole  13 . A cumulative and predetermined number of closed paths like  17  (accomplished progressively) achieves winding of the number of turns required by coil C. As will be more fully described in the following, wire nozzle  20  and stator  10  is also provided with relative radial motions S 1  and S 2 , which are substantially parallel to pole piece sides  13 ″ (and substantially perpendicular to central axis  12 ) in order to accomplish the previously described wire stratification. The stratification formation requires accomplishing closed paths like  17  on a number of adjacent parallel planes that are parallel to the first plane (the plane of FIG. 2). In other words, the multiple wires are dispensed on adjacent planes that are parallel to each other and which are substantially perpendicular to radii that perpendicularly emanate from central axis  12 .  
         [0023]    With reference to FIG. 2, position P 1  shows wire nozzle  20  when it is just about to start traversing a longitudinal extension of gap  16 . In order to accomplish the necessary stroke to traverse the longitudinal extension, translation T 1  is combined with rotation R 1  to accommodate the angle of incline of the longitudinal extension with respect to central axis  12 . Position P 2  shows wire nozzle  20  during the previously described stroke. Position P 3  shows wire nozzle  20  when the previously described stroke is just about to end. Position P 4  shows wire nozzle  20  when a rotation R 1  is occurring. Position P 5  shows wire nozzle  20  when rotation R 1  is about to end and an opposite stroke to traverse the opposite extension of gap  16  is just about to start. Position P 6  shows wire nozzle  20  during the return stroke to traverse the opposite extension of gap  16  which includes translation T 2  and rotation R 2 . Position P 7  shows wire nozzle  20  when the return stroke is just about to end. Position P 8  shows wire nozzle  20  when a rotation R 2  is occurring. It should be understood that the relative movement from P 3  to P 5  and from P 7  to P 1  may include movements in addition to rotations R 1  and R 2 , respectively. For example, translations T 1  and T 2  and stratification motions S 1  and S 2  may be programmed during those strokes to dispose wires W 1 , W 2 , and W 3  in a tensioned manner against ends  13 ′″ of pole piece  13 . Similarly, the traversing strokes from position P 1  to P 3  and from position P 5  to P 7  may also be further programmed to include stratification motions S 1  and S 2 .  
         [0024]    As shown in FIG. 2, wire nozzle  20  needs to be in a particular orientation with respect to gap  16  during the traversing stroke to dispense wires W 1 , W 2  and W 3  within slot spacing  15  in a tensioned manner against the sides of pole piece  13  without twisting or overlap of the wires. In addition, it should be understood that wire nozzle  20  must occupy a portion of gap  16  during each of the traversing strokes (see FIG. 3) so that it is partially inserted into spacing  15 . As previously described, in order to cope with the incline of gap  16  and spacing  15  with respect to central axis  12  of the stator core, portions of rotations R 1  and R 2  need to be combined with translations T 1  and T 2  so that wire nozzle  20  moves within gaps  16  without collision with the borders of expansions  13 ′.  
         [0025]    To avoid twisting wires W 1 , W 2  and W 3  during translations and rotations T 1 , T 2 , R 1 , and R 2 , wire nozzle  20  needs to be oriented differently depending on the relative position which it occupies around pole piece  13  (i.e., the position of nozzle  20  on closed path  17 ). In other words, wire nozzle  20  needs to be steered or programmably controlled during translations and rotations T 1 , T 2 , R 1 , and R 2  to appropriately orient wire exits  21 ,  22 , and  23  and to reduce the necessary size of gaps  16 .  
         [0026]    With reference to FIGS. 2 and 3, and considering that wire nozzle  20  is traveling on closed path  17  with either a clockwise or counterclockwise direction around pole piece  13  (in the case of FIG. 2, wire nozzle  20  is accomplishing closed path  17  in a clockwise direction), steering of wire nozzle  20  around central axis  34  of the wire nozzle keeps wire exit  21  (or a front portion of the wire nozzle) always at the forward end of wire nozzle  20  in the relative direction of movement of wire nozzle  20  along the closed path  17 . This avoids twisting of wires W 1 , W 2  and W 3  during winding. As will be more fully explained in the following, steering of wire nozzle  20  around axis  34  requires causing wire nozzle  20  to perform predetermined rotations R 0  around axis  34  so that wire nozzle  20  can be appropriately oriented around axis  34  as it travels on closed path  17 .  
         [0027]    With reference to FIG. 3, wire nozzle  20  is connected to the top of shaft  31  by means of flange portion  32 ′. Flange portion  32 ′ is bolted to the top of shaft  31  by means of screws  32 ″. Shaft  31  is also provided with a pulley portion  33  engaged by belt  46 . Shaft  31  is supported for rotation around axis  34  using support bushings  35  and  36  seated in support plates  39  and  40 , respectively. Support plates  39  and  40  are distanced from each other by means of upright plate  44 . Support plates  39  and  40  and upright plate  44  can be joined to form a single arm structure, as shown in FIG. 3, by means of bolts like  45 . Belt  46  can circle around upright plate  44 .  
         [0028]    By driving belt  46 , wire nozzle  20  can be provided with rotation R 0  around axis  34  to achieve the appropriate orientations. Shaft  31  is hollow and flared in end  31 ′ for smooth passage of wires W 1 , W 2  and W 3 . Wire nozzle  20  is provided with a lower bore  35  for passage of wires W 1 , W 2 , W 3  from shaft  31  to wire nozzle  20 . Lower bore  35  communicates with an enlarged hollow portion  36  of wire nozzle  20  where wires W 1 , W 2  and W 3  separate to reach their respective wire exits  21 ,  22 ,  23 .  
         [0029]    Wire exits  21 ,  22 , and  23  are on separate surfaces  21 ′,  22 ′,  23 ′ of wire nozzle  20  which may also be understood to demark separate adjacent parallel planes. Each of these adjacent parallel planes is substantially perpendicular to central axis  34  of wire nozzle  20  and substantially parallel to the first plane. In this way, wires W 1 , W 2  and W 3  can be dispensed from wire nozzle  20  along separate courses like  41 ,  42  and  43 , respectively. Dispensing of the wires along these different courses is another feature for avoiding twisting of wires W 1 , W 2 , and W 3  during any relative movements of wire nozzle  20  with respect to the stator core  10 .  
         [0030]    Furthermore, wire exits  21 ,  22 , and  23  may be maintained in predetermined orientations around axis  34  as wire nozzle  20  travels along closed path  17 . In other words, wire nozzle  20  is steered or programmably controlled by maintaining the orientation of an axis in the first plane that is aligned with the wire exits with respect to an instantaneous relative direction of movement of nozzle  20 . The angle between this wire exit axis in the first plane and the instantaneous relative direction of movement being defined as angle A. Particularly, the angular orientation of the wire nozzle (around axis  34 ) and therefore the orientation of the wire exit axis is programmably controlled to vary as nozzle  20  travels along closed path  17 . Therefore, angle A may be constant in certain portions of the closed path (e.g., during the traversing strokes) and variable in other portions (e.g., during rotations R 1  and R 2 ). The configuration of the external surface (formed by sides  13 ″ and ends  13 ′″) of pole piece  13  may determine the choice of angle A. For example, a circular configuration of the ends of pole piece  13  may require a variation of angle A so that the wire exit axis in the first plane containing wire exits  21 ,  22 , and  23  is maintained substantially tangent to the circular configuration of the exterior contour of ends  13 ′″.  
         [0031]    Further, in the embodiment of the wire nozzle shown in FIG. 2 in which wire nozzle  20  has a length and a width, it may be understood that the angular orientation of wire nozzle  20  about axis  34  is programmably controlled so as to minimalize a cross sectional area of the wire nozzle with respect to the instantaneous relative direction of movement of wire nozzle  20  (i.e., by orienting the length of wire nozzle  20  with the direction of movement). The previously mentioned cross sectional area of wire nozzle  20  being taken across a plane that is substantially perpendicular to the instantaneous relative direction of movement of wire nozzle  20  in the first plane of FIG. 2. Such a scheme of orienting wire nozzle  20  may be especially useful during the traversing strokes to minimize the required size of gaps  16  and reduce the likelihood of collision or interference with wires already wound within spacings  15 . Such an orientation may also be understood as an alignment of the wire exit axis with the instantaneous relative direction of movement of wire nozzle  20  such that angle A is zero.  
         [0032]    With reference to FIG. 4, plates  39  and  40  are joined to appendix  50  of carriage structure  51  by means of bolts like  52 . Motor unit  53  can be supported by plate  39  and fastened to it with bolts  54 . Pulley wheel  55  is assembled to the output shaft of motor unit  53 . Pulley wheel  55  is engaged by belt  46  so that rotation of the motor unit causes rotations RO of wire nozzle  20  around axis  34 . Carriage structure  51  is provided with further appendixes  56 . Each of appendixes  56  have slide portions  57  that are able to run on guides  58 . Guides  58  are supported by frame structure  59  (shown partially in FIGS. 4 and 5) in order to be substantially perpendicular to the planes in which translations T 1  and T 2  are accomplished. Motor unit  60  driving screw  61  (which is engaged in a threaded portion of carriage structure  51 ) is provided for causing carriage structure  51  to run along guides  58 . Guides are also parallel to directions S 1  or S 2  used for the stratification motion of wire nozzle  20 .  
         [0033]    In other words, by actuating motor unit  60 , plates  39  and  40  are able to run in directions S 1  or S 2  (i.e., parallel to guides  58 ) so that wire nozzle  20  can move in radial directions S 1  or S 2  to stratify wires W 1 , W 2  and W 3  along pole piece  13 . During the relative movements of wire nozzle  20  and stator core  10 , wires W 1 , W 2 , and W 3  may run unimpeded to end  31 ′ of shaft  31  from a wire source and tension unit (not shown) in order to be dispensed from the exits of wire nozzle  20 . Positioning of the stator core  10  with respect to wire nozzle  20  can be achieved by means of assembly  70  shown in FIG. 5. More particularly, assembly  70  holds the stator core in a predetermined position with respect to frame structure  59 .  
         [0034]    Assembly  70  may be similar to the portion of apparatus shown in the previously incorporated Stratico et al. U.S. patent for rotating and indexing the stator core. Motor unit  71  and rotation bar  74  of assembly  70  are used for rotating the stator core for rotations R 1  and R 2 . Rotation bar  74  bears a gear (not shown), which engages an annular gear (not shown) surrounding stator core  10  so that rotation of the rotation bar  74  rotates the annular gear and consequently stator core  10 . Motor unit  72  and screw  73  of assembly  70  may be used to provide stator core  10  with translations T 1  and T 2 . The aforementioned gear borne by rotation bar  74  has keyways which allow the gear to translate along rotation bar  74  to remain in engagement with the aforementioned annular gear during translations T 1  and T 2 .  
         [0035]    Motors units  53 ,  60 ,  71  and  72  may be actuated and controlled by control system  73  along signal and electric supply lines  53 ′,  60 ′,  71 ′, and  72 ′, respectively. Control system  73  is configured according to the latest available techniques for controlling and programming general motions and positioning with NC axes (numerical controlled axes).  
         [0036]    Sequence and regulation algorithms using externally input data may be applied by control system  73  to actuate the motor units so that translations T 1  and T 2 , rotations R 1  and R 2 , stratification motions S 1  and S 2 , and rotations RO are performed as operations which follow a sequential order, or in combination with each other. Precise synchronization between these movements may be guaranteed by control system  73 . The values of these movements may be found through practical trials which involve winding the actual wires on representative models of the pole configurations. Furthermore, three-dimensional computer simulation of the wire nozzle and stator core motions with respect to the pole piece configuration, together with representations of the various wire extensions from the wire nozzle to the pole piece in the various instances of the motions, may be used to determine the initial values for the practical trials.  
         [0037]    Thus, improved systems and methods for a wire nozzle that simultaneously winds multiple wires onto a dynamo-electric machine component while preventing wire twisting and reducing the needed gap spacing by controlling an orientation of the nozzle is provided. One skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which are presented for the purpose of illustration and not of limitation.