Abstract:
An automated flanging machine is provided. More specifically, a machine for automatically sewing a flange onto a work panel having a consistent corner radius and a straight edge is provided. The machine has a table adapted to support a work panel, a sewing head mounted directly adjacent to the table for performing a sewing operation on the work panel, a turning arm mounted adjacent to the table, and a rear conveyor for selectively moving the work panel on the table. The table may include a corner pivot mechanism for stabilizing the panel while the turning arm turns the panel 90 degree relative to an initial position, and for maintaining a consistent corner radius for sewing. The machine may also include a rear material guide and encoding arm for measuring the progression of the work panel as it is sewn along a side by the sewing head.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     TECHNICAL FIELD 
     The present invention generally relates to automated sewing machinery. More particularly, the invention relates to an automated flanging machine for sewing a flange onto a work panel having a consistent corner radius and a straight edge. 
     BACKGROUND OF THE INVENTION 
     The sewing of large panels of material often involves manual manipulation by an operator. For example, when sewing a flange onto bedding panels having a predetermined size and straight edges, a high level of skill and attention is required by the operator during sewing and manipulation of the panel along each side. To reduce the amount of operator attention required during sewing, some panels are sewn using automated methods. 
     One problem with automated sewing machinery is ensuring that panels may be automatically sewn with a consistent corner radius and straight edges. For example, some automated sewing machines follow the cut edge of a work panel, and therefore do not automatically produce straight sewn edges when the sides of a panel are not cut along a straight line. Further, if the automatic turning of a work panel is not accurate, the finished work panel may be sewn with varying corner angles, creating a trapezoid-shaped panel. In addition to straight edges and consistent corner turns, it is also important that a panel may be manipulated and turned during sewing with minimal operator intervention. 
     Accordingly, a need exists for an automated flanging system that automatically sews a flange onto panels having a consistent corner radius and straight edges, with minimal operator intervention, which addresses the foregoing and other problems. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention generally relates to an automated flanging machine that requires minimal operator intervention and sews work panels having a consistent corner radius and straight edges. Throughout the remainder of this application, reference will be made to a “work panel.” It should be understood that the invention contemplates sewing flanges onto all types of panels made of a variety of materials, both bedding and otherwise, and that the invention is not limited to the specific component being operated on. The automated flanging machine has a table with a table surface that supports a work panel during sewing. In one embodiment, an operator loads a work panel on the table surface and enters identifying information associated with the work panel into an operator interface associated with the machine. 
     The table includes a sewing head mounted directly adjacent to the table for performing a sewing operation on the work panel. The operator may actuate a foot pedal that lifts the presser foot of the sewing head while the work panel is loaded onto the machine. After positioning of the work panel onto the table, the machine then automatically sews a flange onto the straight edges of the work panel, creating straight sewn sides and corners with a consistently-sewn radius. In some embodiments, the machine may be used to sew the straight edges and consistent corners of the work panel, without attaching a flange to the bottom of the work panel. 
     To selectively turn the work panel on the table surface, the automated flanging machine utilizes a turning arm mounted adjacent to the table. In embodiments, the turning arm is engaged against a work panel during turning of the work panel (and sewing of the corner radius), and is not in contact with the work panel during sewing of the sides of the work panel. In further embodiments, a corner pivot mechanism is engaged against the corner of the work panel during turning of the work panel on the table surface. Additionally, the corner pivot mechanism maintains a consistent corner radius while the corner is sewn by the machine. 
     A rear conveyor, having a conveyor belt and a conveyor pressure skid, is mounted adjacent to the table. The conveyor belt advances the work panel along the table surface. In embodiments, the conveyor pressure skid is engaged against the work panel during sewing of the straight sides of the work panel, and is not in contact with the work panel while the work panel is being turned (and the corners are being sewn). A material guide and encoding arm is utilized to measure the progression of the work panel as it is sewn by the sewing head. In embodiments, the material guide and encoding arm is engaged against the edge of the work panel during sewing of the straight edges of the work panel, and is not in contact with the work panel during turning of the work panel. The machine also includes a flange knife assembly that cuts the flange once sewing of the work panel is completed. 
     Additional objects, advantages, and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. 
    
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWING 
       The present invention is described in detail below with reference to the attached drawing figures, wherein: 
         FIG. 1  is a perspective view of one embodiment of the automated flanging machine; 
         FIGS. 2-14  are perspective views of the machine of  FIG. 1 , with a work panel loaded onto the table surface; 
         FIG. 15  is an enlarged, perspective view of the rear conveyor of the machine of  FIG. 1 ; 
         FIG. 16  is an enlarged, perspective view of the sewing area of the machine of  FIG. 1 ; and 
         FIG. 17  is an enlarged, perspective view of the material guide and encoding arm of the machine of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An embodiment of an automated flanging machine  10  is seen in  FIGS. 1-17 . Referring first to  FIG. 1 , automated flanging machine  10  includes a table surface  12 , a sewing head  14 , a turning arm  16 , a rear conveyor  18 , a conveyor belt  20 , a conveyor pressure skid  22 , a corner pivot mechanism  24 , a material guide and encoding arm  26 , a flange knife assembly  28 , a trailing edge sensor  30 , and an operator interface  64 . In some embodiments, the height of the machine  10  may be adjusted by an operator of the machine  10 , such that the table surface  12  reaches the operator&#39;s optimal standing working height. Further, although not depicted in  FIG. 1 , the sewing head  14  may be associated with a foot pedal that the operator may use to raise and/or lower a presser foot of the sewing head  14 . 
     The rear conveyor  18  includes the conveyor belt  20  and the conveyor pressure skid  22 , which will be discussed later with reference to  FIG. 15 . The rear conveyor  18  selectively moves a work panel on the table surface  12 , such as work panel  32  depicted in FIG.  2 . As such, the conveyor belt  20  and conveyor pressure skid  22  are engaged against the work panel  32  during sewing of a straight side of the work panel  32 , and are disengaged from the work panel  32  during turning of the work panel  32  (and sewing of the corner radius). In embodiments, the conveyor belt  20  of the rear conveyor  18  moves in the same direction and at the same rate as the sewing head  14 , in order to advance a work panel along the table surface  12  at a consistent speed. 
     As will be discussed in more detail with reference to  FIG. 17 , the material guide and encoding arm  26  follows the edge of a work panel  32  as it is sewn by the machine  10 , and moved along the table surface  12 . In following the edge of the work panel  32 , the material guide and encoding arm  26  measures the distance sewn along the straight edges of the work panel  32 , which allows the machine  10  to determine when the work panel  32  is ready to be turned. 
     The turning arm  16  is capable of selectively engaging against a work panel  32 . During turning and sewing of the corner radius of the work panel  32 , the turning arm  16  is engaged against the work panel  32 , and is not in contact with the work panel during sewing along the straight sides of the work panel  32 . Similarly, the corner pivot mechanism  24  is engaged against the corner of a work panel during turning (and sewing of the corner radius), and is not in contact with the work panel during sewing (along the straight sides of the work panel  32 ) by the sewing head  14 . 
     As shown in  FIG. 2 , a work panel  32  may be loaded on to the table surface  12  of the machine  10  for automatic sewing of a flange by the sewing head  14 . The work panel  32  has a first side  36 , a second side  38 , a third side  40 , and a fourth side  42 . In embodiments, the machine  10  is used to sew together two or more layers of material making the work panel  32 , or “close” the material of a work panel  32  together. For example, when the operator loads the work panel  32  onto the machine  10 , the edges may be “open” (i.e. not sewn together). In some embodiments, the work panel  32  is constructed of a bottom sheet of fabric, several middle layers of various types of foam and fiber fill, and top sheet of fabric. Prior to loading the work panel  32  onto the machine  10 , these layers of materials may be quilted on a quilting machine, with the work panel  32  being cut on its edges to the rough size of the finished work panel  32 . The machine  10  may then used to both close the edges of the work panel  32  and, at the same time, attach a flange to the bottom side of the work panel  32 . In further embodiments, the machine  10  is only used to close the edges of the work panel  32 , and does not attach a flange to the closed edge of the work panel  32 . In both embodiments (either closing the edges of the work panel  32  and attaching a flange, or simply closing the edges of the work panel  32  without attaching a flange), the machine  10  is used to produce a finished work panel  32  with sewn straight edges and corners sewn with a consistent corner radius, while measuring the work panel  32  in length and width. As such, sewing a work panel  32  with straight edges and consistent corners while measuring length and width produces a work panel  32  that is finished to the required dimensions. 
     Having loaded the work panel  32  onto the table surface  12 , an operator may enter identifying information related to the work panel  32  into the operator interface  64 . For example, the operator may select a pre-loaded SKU number (a “stock-keeping unit” number) from the operator interface  64 . Alternatively, the operator may input a new SKU number into the operator interface  64 , which identifies the work panel  32 . Such identifying information input by the operator may include the total size of the work panel  32 , the length of the straight sides of the work panel  32 , the corner radius to be sewn on the corners of the work panel  32 , and the like. 
     When preparing the work panel  32  for sewing by the machine  10 , the operator may actuate a foot pedal to raise and/or lower the presser foot  34  of the sewing head  14 . In doing so, a flange will be fed through the flange knife assembly  28  and underneath the presser foot  34  of the sewing head  14 . In embodiments, the presser foot  34  may be raised to varying heights to allow an operator to load various thicknesses of work panels  32  onto the machine  10 . 
     In one embodiment, the presser foot  34  may be raised up to 1.5 inches from the table surface  12  to allow for loading of a heavier-weighted work panel  32 . In preparing the work panel  32  for sewing by the machine  10 , in some embodiments, the operator uses a laser line generator to project a laser line onto the work panel  32  so that the operator can align the work panel  32  on the table surface  12  of the machine  10 . For example, the operator may align certain features within the quilted pattern of the work panel  32  with the laser line, thus allowing the work panel  32  to be cut and sewn in along a line that is parallel to the features of the work panel  32 . 
     Having confirmed that the work panel  32  is loaded correctly onto the table surface  12  of the machine  10 , the operator may engage the rear conveyor  18  by selection of an option from the operator interface  64 . In doing so, the conveyor belt  20  will engage against the bottom surface of the work panel  32 , and the conveyor pressure skid  22  will engage against the top surface of the work panel  32 , thereby securing the work panel  32  for movement. In embodiments, the conveyor belt  20  and conveyor pressure skid  22  secure the work panel  32  with minimal pressure between the two parts of the rear conveyor  18 . A foot pedal associated with the sewing head  14  may then be released and the presser foot  34  of the sewing head  14  may engage against the work panel  32  for the machine  10  to begin automatically sewing a flange around the perimeter of the work panel  32 . 
     As previously discussed, the conveyor belt  20  and the presser foot  34  of the sewing head  14  move at a consistent pace to advance the work panel  32  during sewing. During sewing, the material guide and encoding arm  26  may then engage against the rear edge of the work panel  32 . In embodiments, the material guide and encoding arm  26  clamps the edge of the work panel  32 , such as clamping the fourth side  42  of the work panel  32  depicted in  FIG. 2 . In doing so, the material guide and encoding arm  26  follows the edge of the work panel  32  while the first side  36  of the work panel  32  is sewn by the sewing head  14 . In embodiments, a linear encoder in the material guide and encoding arm  26  is used to measure the distance sewn by the sewing head  14  along the straight sides of the work panel  32 . 
     Turning next to  FIG. 3 , as the trailing edge of the first side  36  of the work panel  32  approaches the sewing head  14 , the trailing edge sensor  30  detects that the machine  10  has completed sewing at least a portion of the first side  36  of the work panel  32 . Having sensed the trailing edge of the first side  36 , the trailing edge sensor  30  indicates to the machine  30  that the work panel  32  is ready to be turned, and the corner radius is ready to be sewn. As shown in  FIG. 3 , in order to turn the work panel  32 , the turning arm  16  and the corner pivot mechanism  24  engage against the work panel  32 . Engaging the corner pivot mechanism  24  against the work panel  32  provides a pivot point around which the machine  10  can sew a consistent corner radius. For example, when turning the work panel  32  from sewing the first side  36  to sewing the second side  38 , the corner pivot mechanism  24  maintains a constant distance between the sewing head  14  and the edge of the work panel  32 , thus ensuring that the machine  10  sews a consistent corner radius with the sewing head  14 . 
     Also depicted in  FIG. 3 , the cylinders of the turning arm  16  actuate and engage the work panel  32  to turn the work panel  32  to a position that is 90 degrees relative to the initial position of the work panel  32 . For example, the turning arm  16  turns the work panel  32  from sewing along the first side  36  to sewing along the second side  38 . Once the turning arm  16  and the corner pivot mechanism  24  are engaged with the work panel  32 , the material guide and encoding arm  26  and rear conveyor  18  disengage from the work panel  32  so that the turning arm can reposition the work panel  32 . 
     Referring next to  FIG. 4 , with the material guide and encoding arm  26  disengaged from against the work panel  32 , the turning arm  16  rotates the work panel  32  to a position 90 degrees relative to the original line sewn along the first side  36 , while continuing to sew the corner radius of the work panel  32  with the sewing head  14 . During turning, the sewing head  14  sews a consistent corner radius between two sides of the work panel  32 , such as the corner radius between the first side  36  and the second side  38 . As such, the corner pivot mechanism  24  maintains a constant distance between the edge of the work panel  32  and the sewing head  14 , which creates a consistently-sewn corner radius on the work panel  32 . 
     As shown in  FIG. 5 , the corner between the first side  36  and the second side  38  has been sewn. Prior to beginning sewing the second side  38 , the rear conveyor  18  engages against the work panel  32 . Further, the material guide and encoding arm  26  moves forward into contact with the work panel  32  and clamps the work panel  32  at the rear edge of the sewing head  14 . Additionally, the cylinders of the turning arm  16  disengage and the turning arm  16  rotates back to its original position while the corner pivot mechanism also disengages from the surface of the work panel  32 , as shown in  FIG. 6 . As further depicted in  FIG. 6 , the clamp of the material guide and encoding arm  26  is engaged against the first side  36  of the work panel  32 , as the machine  10  prepares to sew the second side  38  of the work panel  32 . The point at which the material guide and encoding arm  26  clamps the work panel  32  is a known distance from the needles of the sewing head  14  because the sewing head  14  has just completed sewing the corner radius between the first side  36  and the second side  38 . 
     As the machine  10  begins sewing the second side  38  of the work panel  32 , the material guide and encoding arm  26  begins measuring the distance that is sewn using a linear encoder, as shown in  FIG. 7 . When the distance sewn along the second side  38 , added to the known distance where the work panel  32  is clamped by the material guide and encoding arm  26 , equals the programmed length of the work panel minus the corner radius, the corner pivot mechanism  24  and the turning arm  16  engage to contact the work panel  32 . For example, for a programmed work panel  32  having a total length of 20 inches and a corner radius sewn between the first side  36  and the second side  38  of 3 inches, the corner pivot mechanism  24  and the turning arm  16  will engage when the distance sewn along the second side  38  (as measured by the linear encoder of the material guide and encoding arm  26 ) added to the known distance where the work panel is clamped by the material guide and encoding arm, is equal to 17 inches. 
     As shown in  FIG. 8 , the known distance (the point at which the material guide and encoding arm  26  is clamped to the work panel  32 ) added to the distance measured by the material guide and encoding arm  26  during sewing of the second side  38  of the work panel  32 , equals the programmed length of the work panel  32  minus the corner radius. As such, the work panel  32  is ready to be turned for sewing of the corner between the second side  38  and the third side  40 , as well as the sewing of the third side  40 . As shown in  FIG. 9 , the clamp of the material guide and encoding arm  26  is disengaged from the edge of the work panel  32  and the corner pivot mechanism  24  and turning arm  16  engages against the work panel  32 . The rear conveyor  18  is also disengaged from the work panel  32  during turning. The turning of the work panel around the corner between the second side  38  and the third side  40  is depicted in  FIG. 9 . As such, the same corner radius sewn between the first and second sides  36  and  38  is sewn between the second and third sides  38  and  40 . 
     In  FIG. 10 , having completed sewing the second corner of the work panel  32 , the machine  10  is prepared to sew the third side  40  of the work panel  32 . As previously discussed, in preparation for sewing the third side  40 , the clamp of the material guide and encoding arm  26 , the conveyor pressure skid  22 , and conveyor belt  20 , are engaged against the work panel  32 . Further, the turning arm  16  and corner pivot mechanism  24  are disengaged from the work panel  32 . The third side  40  and the corner between the third side  40  and the fourth side  42  are sewn similarly to the second side  38  (and the corner between the second side  38  and the third side  40 ) discussed above. 
     Referring next to  FIG. 11 , the machine  10  has completed sewing the fourth side  42 . As discussed above, the sewing head  14  is determined to have completed sewing the fourth side  42  when the known distance (where the fourth side  42  is clamped by the material guide and encoding arm  26 ) added to the measured distance sewn (as measured by the material guide and encoding arm  26  during sewing of the fourth side  42 ) equals the programmed length (a pre-determined number programmed into the operator interface  64 ) minus the corner radius (the corner radius sewn at each corner when turning the work panel 90 degrees relative from one side of the work panel to the next). 
     As shown in  FIG. 12 , the corner radius between the fourth side  42  and the first side  36  is sewn while the work panel  32  is turned. As previously discussed, the material guide and encoding arm  26  and the rear conveyor  18  are disengaged during turning and sewing of the corner, while the corner pivot mechanism  24  and the turning arm  16  are engaged against the work panel  32 . In  FIG. 13 , having turned the work panel  32  so that the first side  36  is again aligned with the sewing head  14 , the operator sews at least a portion of the first side  36 , to the point where sewing began along the first side  36 . As the end sewing line sewn by the sewing head  14  approaches the beginning sewing line sewn by the sewing head  14 , the operator actuates the flange knife assembly  28  by selecting an option from the operator interface  64 , as shown in  FIG. 14 . The flange knife assembly  28  actuates to cut off the flange, and the finished work panel  32  may be sewn off. As previously discussed, in some embodiments, the machine  10  sews the straight edges and consistent corners of the work panel  32  without attaching a flange to the bottom side of the work panel  32 . 
     Turning next to  FIG. 15 , an enlarged view  44  of the rear conveyor  18  is shown. As depicted in the cut-away portion of the table surface  12 , the rear conveyor  18  includes a conveyor belt  20  which engages against the bottom surface of a work panel  32 . Further, the conveyor pressure skid  22  may be lowered into contact with a work panel  32 . As previously discussed, engaging both the conveyor belt  20  and the conveyor pressure skid  22  of the rear conveyor  18  enables the work panel  32  to be advanced during sewing by the machine  10 . In some embodiments, because of the pressure applied by the components of the rear conveyor  18 , the work panel  32  is fed at a consistent rate through the machine  10 , and the sides of the work panel  32  are sewn in a straight line by the sewing head  14 . 
     With reference to  FIG. 16 , an enlarged view of the sewing area  46  is shown. The sewing area  46  includes the sewing head  14  and the presser foot  34 , which are used to sew the straight edges of the work panel  32 . Also viewed in the enlarged sewing area  46  are the corner pivot mechanism  24 , the pivot cylinder  48 , the trailing edge sensor  30 , the trailing edge reflector  50 , and the flange knife assembly  28 . In embodiments, the pivot cylinder  48  actuates the pivot mechanism  24  so that the pivot mechanism  24  is engaged against the work panel  32  during turning. The trailing edge sensor  30 , together with the trailing edge reflector  50 , detects the trailing edge of the work panel  32  during sewing, as discussed above with reference to sewing the initial portion of the first side  36 . In embodiments, the trailing edge sensor  30  is used to detect when the sewing head  14  has completed sewing at least a portion of the first side  36 , and also to determine when the machine  10  is ready to turn the work panel  32  for sewing the corner radius between the first side  36  and the second side  38 . When sewing subsequent sides of the work panel  32 , such as the second side  38 , third side  40 , and fourth side  42 , the material guide and encoding arm  26  is used to determine when to turn the work panel  32  and sew the corner radius, as opposed to using the trailing edge sensor  30 . 
     Turning last to  FIG. 17 , the material guide and encoding arm  26  is shown in an enlarged view. The material guide and encoding arm  26  includes a clamp  52 , a linear guide  54 , a gear rack  56 , a constant force spring  58 , an encoder  60 , and a magnetic strip  62 . As previously discussed, the clamp  52  of the material guide and encoding arm  26  is able to engage against the edge of the work panel  32  to measure the progression of the work panel  32  as a straight side is sewn by the sewing head  14 . Such measurement is conducted using the encoder  60 , which may be a linear encoder or another form of measuring device. The constant force spring  58  allows the material guide and encoding arm  26  to follow the edge of the work panel  32  as it is advanced by the sewing head  14  and sewn by the machine  10 . As will be understood, in following the edge of the work panel  32 , the material guide and encoding arm  26  does not apply pulling force to the work panel  32 . Instead, the material guide and encoding arm  26  measures the progression of the work panel  32  as it is advanced by the sewing head  14  and the rear conveyor  18 . 
     From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages, which are obvious and which are inherent to the structure. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.