Patent Abstract:
A mattress edge sewing machine including a frame with a drive shaft rotatably mounted therein and having a material supporting surface, a sewing station defined by a needle bar mounted in the frame for generally vertical reciprocatory movements along a fixed centerline and a feed mechanism for pulling materials along a generally horizontal direction thereby facilitating advancement of multiple mattress material plies through the sewing station of the machine. The feed mechanism includes upper and lower positively driven feed rollers which are continually biased into operable engagement with each other. The feed rollers are arranged in the line of feed of the material and within a range of about 0.4 inch to about 1.0 inch rearwardly of the needle bar centerline whereby facilitating advancement of material through a sewing station on the machine and especially around four corners of a mattress being sewn. The needle bar is moved in timed relation relative to the movements of the looper, and with the needle bar traversing a distance in a single vertical direction at a ratio greater than 2:1 relative to the distance in a single lateral direction traversed by the looper.

Full Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This patent application claims the benefit of provisional patent application Ser. No. 60/777,664; filed Feb. 28, 2006. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention generally relates to sewing machines and, more particularly to a mattress edge sewing machine having a roller feed mechanism for intermittently advancing material through stitch forming instrumentalities on the sewing machine including a thread carrying needle which travels at a ratio greater than 2:1 relative to a thread carrying looper arranged in operable combination with the needle. 
       BACKGROUND OF THE INVENTION 
       [0003]    Specialized edge sewing and taping machines sew and secure peripheral edges of upper and lower mattress panels or a mattress cushion to the side panels thereof. During a mattress sewing operation, a sewing machine moves around a support relative to the mattress and performs a sewing operation about the periphery of the mattress. Chain-stitch sewing machines capable of sewing a Federal Stitch Type 401 are typically used for sewing mattress edges. 
         [0004]    An operator, positioned adjacent to the sewing machine, compresses the mattress to create slack in the fabric panels or shell while continuously pulling an edge of the relative major face panel together with an edge of a side panel while also guiding the mattress into a stitch forming area of the sewing machine. In some applications, a steel wire or spring is arranged adjacent to the mattress seam. Moreover, and as the operator feeds the mattress panels into the sewing station, a narrow covering strip or tape is laid over the seam by a suitable and well known device and is sewn simultaneously with the seam. The strip or tape covers the seam and creates aesthetically acceptable upper and lower edges around the mattress periphery. It should be appreciated, the cumulative width of mattress materials fed into the sewing station of the machine can range in compressed thickness between about 0.187 inches and about 0.5 inches. 
         [0005]    Mattress edge sewing and taping operations have generally required great manual effort due not only to the size and weight of the mattress but also to the constant compression the operator must apply to the mattress as well as the simultaneous tension the operator must apply to the panels mentioned above. This has been a special concern when sewing the four corners of the mattress which require extra handling and guidance efforts. 
         [0006]    Especially when sewing an edge of a mattress, the reciprocal path of the sewing machine needle must be positioned as close as possible to a working edge of a throat plate on the sewing machine. A longer or a larger lateral distance between the path of the needle and the working edge of the sewing machine throat plate tends to allow materials, being advanced through the sewing station, to become removed from beneath the needle especially when a steel ring is arranged adjacent to the material edge being sewn Moreover, increasing the lateral distance between the path of the needle and the working edge of the throat plate proportionately increases problems involved with sewing a proper seam especially around the four corners of the mattress. 
         [0007]    Any conventional chain-stitch sewing machine has sewing instrumentalities including a thread carrying needle and a thread carrying looper arranged in operable combination relative to each other. In such machines, the looper typically travels sideways or laterally across the path of the needle in a direction generally normal to the feeding direction of material. Because the path of the looper crosses the direction of material movement, sewing machines of this design only increase the distance between the path of the needle and the working edge of the throat plate. 
         [0008]    Mattress edge sewing machines present a unique combination of characteristics which complicate the design thereof and are contrary to accepted and well known sewing standards. The needle on a standard chain-stitch sewing machine, between opposed ends of its stroke in a single vertical direction, travels about 1.5 times greater distance than does the looper between opposed ends of its travel in a generally lateral direction. The thickness of material having to be moved through a sewing station of a mattress edge sewing machine, however, requires the vertical travel of the needle to be significantly increased. Normally, the increased travel of the needle necessitates an increased lateral travel of the looper. Requiring the working edge of the throat plate to be positioned as close as possible to the reciprocal path of the needle, however, limits looper travel thus causing significant challenges in creating a proper chain stitch formation in a mattress edge sewing machine. 
         [0009]    Primarily because of the thickness of material having to be feed through the machine, some mattress sewing machines have been known to use a needle feed machine. That is, a sewing machine wherein the sewing needle moves not only in a vertical path of travel but also moves with the material in the direction of material feed. As will be appreciated, designing a needle feed machine adds significantly to the cost of the machine manufacture and furthermore complicates the design of the sewing instrumentalities associated with such machine. 
         [0010]    There are, however, significant material feeding problems associated with sewing a mattress edge simply because of the cumulative thickness of material to be moved through the sewing station of the machine. As will be appreciated, those sewing machines having a needle which reciprocally moves along a fixed path of travel have problems when considering the materials being fed through the machine have a cumulative width ranging between about 0.187 inches and about 0.50 inches. That is, if the material moving through the machine sewing station moves in the direction of feed with the needle in the work, significant damage can result to the needle, the needle bar, the needle bar drive mechanism and related sewing machine components. 
         [0011]    Thus, there remains a need and desire for a mattress edge sewing machine which addresses the above-mentioned concerns and others while offering a low cost solution thereto. 
       SUMMARY OF THE INVENTION 
       [0012]    According to one aspect, there is provided a mattress edge sewing machine including a frame with a drive shaft rotatably mounted therein and having a material supporting surface, a sewing station defined by a needle bar mounted in the frame for generally vertical reciprocatory movements along a fixed centerline, and a feed mechanism for pulling materials along a generally horizontal direction thereby facilitating advancement of multiple mattress material plies through the sewing station of the machine. In one form, the feed mechanism includes upper and lower positively driven feed rollers which are continually biased into operable engagement with each other. Advantageously, the feed rollers are arranged in the line of feed of the material and within a range of about 0.4 inch to about 1.0 inch rearwardly of the needle bar centerline whereby facilitating advancement of material through a sewing station on the machine and especially around four corners of a mattress being sewn. 
         [0013]    Preferably, the mattress edge sewing machine further includes a drive system operably connected to the sewing machine drive shaft for positively driving each roller in timed relation relative to the reciprocal movements of the needle bar. In one form, the drive system for the feed rollers includes a series of intermeshing gears operably arranged between the drive shaft and the feed rollers of the feed mechanism. 
         [0014]    In one embodiment, a throat plate forms part of the material supporting surface of the machine. Moreover, at least the lower feed roller preferably has a serrated peripheral edge for facilitating engagement and advancement of the materials being moved through the sewing station of the machine. In one form, the throat plate and the lower feed roller define cooperating instrumentalities for stripping material inadvertently grasped by the lower feed roller as the mattress material moves through the sewing station of the machine. 
         [0015]    In one embodiment, a mechanism, mounted on the sewing machine frame, is provided for vertically and selectively moving the upper feed roller relative to the material supporting surface on the sewing machine. In a preferred embodiment, the mechanism for vertically and selectively moving the upper feed roller relative to the material supporting surface on the sewing machine is manually operated. 
         [0016]    According to another aspect, there is provided a mattress edge chain-stitch sewing machine having a frame with a material supporting surface, a drive shaft revolubly mounted about a fixed axis in the frame, a reciprocally driven needle bar mounted in the frame and operable along a fixed centerline, and a feed mechanism for advancing material beneath said needle bar in a generally horizontal direction. The feed mechanism comprises a lower feed roller mounted for rotation about a fixed axis arranged below the material supporting surface of the machine and an upper feed roller. The upper feed roller is biased into operable engagement with the lower feed roller and is mounted for rotation about an axis in a manner permitting the upper feed roller to be vertically shifted relative to the lower feed roller. The upper feed roller is permitted to vertically move between a first position, wherein the upper and lower feed rollers are arranged in constant operable combination relative to each other to advance the material beneath the needle bar, and a second position. In the second position, the upper and lower feed rollers are separated from operable engagement relative to each other. The upper and lower feed rollers are arranged in the line of and rearwardly of the needle bar centerline by a distance ranging between about 0.4 inches and about 1.0 inch, measured in the direction of material advancement, with the upper and lower feed rollers being positively and intermittently driven such that the material advancing beneath the needle bar is moved in timed relation relative to the reciprocation of the needle bar. 
         [0017]    Preferably, a drive system is operably connected to the drive shaft and positively drives each feed roller in timed relation relative to reciprocal movements of the needle bar. The drive system includes a series of gears arranged in intermeshing relation relative to each other to effect positive movements of the feed rollers. 
         [0018]    In one form, at least the lower feed roller has a serrated peripheral edge for facilitating engagement and advancement of the material moving through the sewing station. In another form, the upper and lower feed rollers each has a serrated peripheral edge for facilitating engagement and advancement of the material moving through said sewing station. In this regard, the sewing machine further includes structure for stripping material away from the periphery of either feed roller thereby enhancing material movement through the sewing machine. 
         [0019]    In a preferred form, the mattress edge sewing machine further includes a mechanism for vertically and selectively moving the upper feed roller relative to the material supporting surface on the sewing machine. In one embodiment, the mechanism for vertically and selectively moving the upper feed roller relative to the material supporting surface on the sewing machine is manually operated. 
         [0020]    According to another aspect, there is provided a mattress edge chain-stitch sewing machine including a frame, a needle bar mounted for generally vertical reciprocatory movements within the frame along a fixed axis, and a throat plate forming part of a material supporting surface of the machine. The throat plate defines a working edge for the machine and is disposed in laterally proximate relation from the fixed axis of the needle bar. A looper is mounted for movements laterally across the direction of feed of the machine. A tip of the looper remains to one lateral side of the working edge of the throat plate throughout its extent of travel. The needle bar is moved in timed relation relative to the movements of the looper, and with the needle bar traversing a distance in a single vertical direction at a ratio greater than 2:1 relative to the distance in a single lateral direction traversed by the looper. 
         [0021]    Preferably, the mattress edge sewing machine further includes a feed mechanism for pulling materials along a generally horizontal direction and beneath the needle bar. In one form, the feed mechanism includes a lower positively driven feed roller mounted on the frame for rotation about a fixed axis arranged below the material supporting surface of the machine and an upper feed roller. The upper feed roller is positively driven and is mounted on the frame for rotation about an axis arranged above the material supporting surface of the machine. In one embodiment, the upper and lower feed rollers are mounted on the sewing machine such that a distance ranging between about 0.4 inches and about 1.0 inch, measured in the direction of material advancement, separates the centerline of the upper and said lower feed rollers relative to the centerline of said the needle bar. 
         [0022]    Preferably, the upper feed roller is mounted on the machine in a manner permitting the upper feed roller to be shifted relative to the lower feed roller between first and second positions. In the first position, the upper and lower feed rollers are arranged in operable combination relative to each other to pull materials along a generally horizontal direction beneath said needle bar. In the second position, the upper and lower feed rollers are separated from operable engagement relative to each other. 
         [0023]    According to yet another aspect, there is provided a mattress edge chain-stitch sewing machine having a frame, a drive shaft revolubly mounted in the frame, a needle bar driven by the shaft and reciprocal along a fixed path of travel, and a throat plate arranged beneath the needle bar and forming part of a material supporting surface for the machine. An edge of the throat plate is disposed in proximate lateral relation to the needle bar and defines a working edge for the machine. The sewing machine further has a stitch forming mechanism including stitch forming instrumentalities including a needle mounted to a lower end of the needle bar for movement along a fixed generally vertical reciprocal path of travel, and a looper. The looper is arranged for generally elliptical and across-the-line of feed movements relative to and in combination with the needle to form chain-stitches in a workpiece. During a sewing operation, a tip of the looper remains to one lateral side of the working edge of the sewing machine. During a sewing operation, the needle traverses a distance in a single vertical direction at a ratio greater than 3:1 relative to the distance in a single lateral direction traversed by said looper. 
         [0024]    Primarily because of the thickness of material moving through sewing station, the mattress edge sewing machine preferably includes a needle guard. In a preferred form, the needle guard is driven in timed relation relative to the movement of the needle during the stitch forming cycle of the sewing machine. 
         [0025]    In view of the above, one object of this invention is to provide a mattress edge chain-stitch sewing machine having a feed mechanism comprised of a pair of feed rollers arranged on the machine such that the axis about which each feed roller rotates is disposed in proximate to the needle thereby enhancing advancement of the material being sewn through a sewing station of the machine especially as the machine moves about the four corners on the mattress. 
         [0026]    Another object of the present invention is to provide a mattress edge chain stitch sewing machine having a pair of intermittently driven feed rollers arranged on the machine such that the axis about which each feed roller rotates is disposed proximate to the needle and which are positively driven only when the needle is out of the material being sewn. 
         [0027]    Still another feature of this invention relates to the provision of a mattress edge chain stitch sewing machine including a thread carrying needle, which moves along a vertical reciprocatory path which is fixed relative to a frame of the machine, and a looper which moves across the line of feed to cooperate with the needle to form chain-stitches, and wherein, in one vertical direction of travel, the needle travels a distance equal to at least twice the lateral distance traveled by the looper in a single stitch forming cycle so as to increase the material handling capacity of the machine. 
         [0028]    Still another feature of this invention relates to providing a mattress edge chain-stitch sewing having stitch forming instrumentalities including a needle movable along a fixed generally vertical reciprocal path of travel, and an across-the-line of feed looper, with a tip of the looper remaining to one lateral side of a working edge of a throat plate on the machine, and with the needle traversing a distance in a single vertical direction at a ratio greater than 3:1 relative to the distance in a single lateral direction traversed by the looper so as to enhance the sewing capacity of the machine. 
         [0029]    These and additional features, objects and advantages of the present invention will become more readily apparent from the drawings and the following description of the invention. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0030]      FIG. 1  is a front view of a mattress edge sewing machine embodying principals of the present invention; 
           [0031]      FIG. 2  is an end view of the mattress edge sewing machine illustrated in  FIG. 1  with parts removed to show internal details; 
           [0032]      FIG. 3  is a fragmentary enlarged front view of the mattress edge sewing machine shown in  FIG. 1  with parts removed to show internal details; 
           [0033]      FIG. 4  is a an enlarged fragmentary end view similar to  FIG. 2 ; 
           [0034]      FIG. 5  is a top plan view schematically illustrating a lateral path of travel traversed by a tip of a looper forming part of the machine illustrated in  FIG. 1 ; 
           [0035]      FIG. 6  is a top left side perspective view of one form of mechanism for imparting elliptical movements to the looper of the mattress edge sewing machine; 
           [0036]      FIG. 7  is top left side perspective view of one form of mechanism for operating a needle guard in timed relation relative to the needle of the mattress edge sewing machine; 
           [0037]      FIG. 8  is an enlarged front view, with parts broken away, to show a portion of a feed mechanism arranged in operable combination with the mattress edge sewing machine; 
           [0038]      FIG. 9  is a rear view of the mattress edge sewing machine shown in  FIG. 1 ; 
           [0039]      FIG. 10  is a fragmentary top plan view, with parts broken away to show details, of one form of feed mechanism for moving material through the mattress edge sewing machine; 
           [0040]      FIG. 11  is an enlarged end view, with parts broken away to show details, of a power train forming part of the feed mechanism illustrated in  FIG. 10 ; 
           [0041]      FIG. 12  is a fragmentary top plan view, with parts broken away to show details, of the feed mechanism for moving material through the mattress edge sewing machine; 
           [0042]      FIG. 13  is an enlarged sectional view taken along line  13 - 13  of  FIG. 10 ; 
           [0043]      FIG. 14  is a top left perspective view of one form of throat plate used in combination with the mattress edge sewing machine shown in the drawings; 
           [0044]      FIG. 15  is an enlarged top plan view of a feed roller area of the throat plate illustrated in  FIG. 14 ; and 
           [0045]      FIG. 16  is a sectional view taken along line  16 - 16  of  FIG. 15 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0046]    While the present invention is susceptible of embodiment in multiple forms, there is shown in the drawings and will hereinafter be described a preferred embodiment of the invention, with the understanding the present disclosure sets forth an exemplification of the invention which are not intended to limit the invention to the specific embodiment illustrated and described. 
         [0047]    Referring now to the drawings, wherein like reference numerals indicate like parts throughout the several views, there is schematically shown in  FIG. 1  a mattress edge chain-stitch sewing machine, generally identified by reference numeral  10 . Sewing machine  10  includes a housing  12  having base portion or bed  14  provided with a work or material supporting surface  16  including a throat plate  17  ( FIG. 2 ), a standard  18  extending vertically from one end of bed  14 , and an arm  20  which overlies bed  14  and terminates in a sewing head portion  22 . A drive shaft  24  axially extends from and is supported in the bed  14  for rotation about a fixed axis  26 . A free end of shaft  24  is operably connected in a conventional fashion to a suitable power source (not shown). 
         [0048]    A needle bar  28  is mounted within the sewing head portion  22  of machine  10 . The needle bar  28  is operably connected to and driven by shaft  24  in a well known conventional fashion. Notably, and as shown in  FIGS. 1 and 2 , the needle bar  28  is mounted for vertically movement along a fixed centerline  29 . In the embodiment illustrated, the needle bar  28  carries, at a lower end thereof, a thread carrying needle  30  forming part of stitch forming instrumentalities of and defining a stitch forming area or sewing station for the machine  10 . 
         [0049]    As shown in  FIGS. 1 and 2 , sewing machine  10  can further include a suitable and conventional apparatus  34  for guiding a suitable tape or other strip into the stitch forming area of machine  10 . During a sewing cycle, and as well known in the art, a tape or strip is guided by apparatus  34  and extends over the exterior of the mattress edges being sewn by machine  10  to provide an enhanced aesthetic exterior appearance to the mattress edge. 
         [0050]    As shown in  FIGS. 2 ,  3  and  4 , machine  10  is further provided with a thread carrying looper  40 . The thread carrying looper  40  is adapted for cooperation with the needle  30  to conventionally form chain-stitches in a workpiece or material being advanced in the direction of arrow  42  ( FIGS. 2 and 4 ) through the sewing station of the machine  10 . In the embodiment illustrated, looper  40  is driven is a generally elliptical path extending across the direction of movement of the material moving through the sewing area of the machine to form a Federal Stitch Type 401 stitch. Such looper movement is commonly referred to as an “across the line of feed” type of looper movement. While illustrated with a looper  40  which moves across the line of feed, it should be appreciated certain aspects of the present invention apply equally to either across the line of feed sewing machines and/or in-line of feed sewing machines. 
         [0051]    In  FIG. 5 , dash line  43  illustrates a schematically enlarged path of movement of the tip  41  of the looper  40  during a sewing cycle. As shown, the path of movement of the looper tip  41  during a sewing cycle is elongated in a direction extending generally normal or across the direction of material movement (as shown by arrow  42 ) passing through the sewing station of the machine. As schematically represented in  FIG. 5 , looper  40  is driven during a sewing cycle such that the looper tip  41  simultaneously partakes of an elongated lateral movement and a fore-and-aft rocking motion. As shown in  FIG. 5 , the looper  40  moves in a counterclockwise direction. In the form shown, looper  40  laterally moves endwise to seize and shed needle thread loops and also includes an alternating fore-and-aft motion to avoid the needle  30  alternatively on opposite sides thereof for sewing chain-stitches (Federal Stitch Type 401). 
         [0052]    As shown in  FIG. 3  and schematically represented in  FIG. 5 , throat plate  17  defines a working edge  19  for the sewing machine  10  extending generally parallel to the direction of feed of material (as represented by arrow  42 ) moving through the machine. As mentioned above, and to aid in controlling the material moving through the sewing station of the machine  10 , the working edge  19  of throat plate  17  is disposed laterally proximate to the centerline  29  of the needle bar  28 . In the illustrated embodiment, and because the tip  41  of looper  40  cannot laterally extend beyond the working edge  19  of the machine  10  during a sewing cycle, lateral movements of the looper  40  are not equally disposed to opposed sides of the needle bar centerline  29 . As shown in  FIG. 5 , the looper tip  41  moves a total distance A which, in the illustrated embodiment, is equal to about 0.406 inches in a single lateral direction. In the illustrated embodiment, and during a sewing cycle, because the looper tip  41  cannot extend beyond the working edge  19  of the sewing machine, looper  40  laterally moves or travels a distance B equal to about three times greater lateral distance to one side of the needle bar  29  than the other. 
         [0053]    Preferably, and to permit machine  10  to sew mattress panels and related materials having a cumulative thickness ranging between about 0.187 inches and about 0.562 inches, the needle bar  28  and, thus, needle  30  traverse or travel a distance which, in a single vertical direction, significantly exceeds the distance traversed or traveled by the looper in a single lateral direction. In a preferred form, and during a sewing cycle, the needle  30  traverses a distance in a single vertical direction greater than two to three times the lateral distance traversed by the looper  40  in a single lateral direction. In the embodiment illustrated, and during a sewing cycle, looper  40  travels or traverses a distance A, in a single lateral direction, which is about equal to 0.406 inches. So as to add significant versatility thereto, and in contrast to accepted sewing techniques, machine  10  is preferably configured such that the needle bar  28  and, thus, needle  30  traverse a distance of about 2.359 inches in a single vertical direction during a sewing cycle. 
         [0054]    To drive the looper  40  both laterally and in a fore-and-aft or rocking motions whereby imparting the requisite and generally elliptical-like movements to the looper  40  in timed relation relative to reciprocation of the needle  30  ( FIG. 4 ), a looper drive mechanism  50  ( FIG. 6 ) is provided. The looper drive mechanism  50  can take a myriad of different designs and shapes without departing or detracting from the principals of the present invention. In the embodiment shown in  FIG. 6 , the looper drive mechanism  50  includes an elongated looper supporting shaft  52  defining an axis  53 . In the illustrated embodiment, the looper supporting shaft  52  is journalled in the bed portion  14  of the machine  10  for both axial and rocking movements along and about axis  53 . Preferably, axis  53  of the looper supporting shaft  52  extends generally parallel to the main drive shaft  24  of machine  10 . As shown in  FIG. 3 , one end of shaft  52  extends beyond housing  12  and has the looper  40  suitably connected thereto as by a suitably shaped support bracket  54 . The axial shifting movements and rocking movements of the looper supporting shaft  52  effectively drive looper  40  in an elliptical path which, as discussed above, extends across the feeding direction of sewn material (as indicated by arrow  42 ) moving through machine. 
         [0055]    In the embodiment shown in  FIG. 6 , looper drive mechanism  50  further includes a first actuator  56  operably connected to the looper supporting shaft  52  for imparting predetermined lateral movements to shaft  52 . As shown in  FIG. 6 , the first actuator  56  includes an eccentric  57  mounted on and rotatable with the main drive shaft  24  of the machine  10 . The eccentric  57  is arranged in operable combination with a follower  58  operably coupled to the looper supporting shaft  52  and which converts the rotational movement of the eccentric  57  into lateral movements of shaft  52  thereby driving the looper  40  in both lateral directions during a sewing cycle. 
         [0056]    In the embodiment shown in  FIG. 6 , looper drive mechanism  50  further includes a second actuator  66  operably connected to the looper supporting shaft  52  for imparting looper avoid movements to shaft  52 . As shown in  FIG. 6 , the second actuator  66  includes an elongated eccentric  67  mounted on and rotatable with the main drive shaft  24  of the machine  10 . Eccentric  67  is arranged in operable combination with a follower  68  operably coupled to the looper supporting shaft  52  and which converts the rotational movement of the eccentric  60  into rocking or pivotal movements of shaft  52  about axis  53  thereby providing the requisite avoid movements of the looper  40  during a sewing cycle. 
         [0057]    In a preferred embodiment, sewing machine  10  is furthermore provided with a driven needle guard mechanism  70  operable in timed relation relative to movements of the needle  30 . Needle guard mechanism  70  can take a myriad of different designs and shapes without departing or detracting from the principals of the present invention. In the embodiment shown in  FIG. 7 , the needle guard mechanism  70  includes an elongated shaft  72  defining an axis  73 . In the illustrated embodiment, shaft  72  is journalled in the bed portion  14  of the machine  10  for rocking movements about axis  73 . Preferably, axis  73  extends generally parallel to the main drive shaft  24  of machine  10 . One end of shaft  72  extending beyond housing  12  has a guard  74  suitably connected thereto and radially projecting therefrom. A free end of the guard  74  defines a camming surface  75  for engaging and operably positioning a lengthwise portion of the needle  30  ( FIG. 4 ) disposed beneath the throat plate  17  ( FIG. 4 ) for operable combination with the looper  40  during a sewing cycle. 
         [0058]    In embodiment illustrated in  FIG. 7 , mechanism  70  further includes an actuator  76  operably connected to shaft  72  for imparting predetermined movements to guard  74 . As shown in  FIG. 7 , actuator  76  preferably includes an eccentric  77  mounted on and rotatable with the main drive shaft  24  of machine  10 . The eccentric  77  is arranged in operable combination with a follower  78  operably coupled to shaft  72  and which converts the rotational movement of the eccentric  77  into rocking movements of shaft  72  about axis  73  thereby positioning the guard  74  and camming surface  75  in timed relation relative to reciprocation of the needle  30 . 
         [0059]    Because machine  10  is provided with an internal lubrication system (not shown), concerns over friction and heat build-up between the looper drive shaft  52 , the bed portion  14  of machine  10 , the eccentrics  56  and  66  and their respective followers  58  and  68 , along with the needle guard shaft  72 , the bed or base portion  14  of machine  10 , along with the eccentric  76  and its follower  78  are substantially eliminated. 
         [0060]    Because machine  10  must be capable of advancing materials having a cumulative thickness of up to about 0.562 inches through the sewing area, machine  10  is further provided with a feed mechanism  80 . In the preferred embodiment illustrated in  FIG. 4 , feed mechanism  80  includes a pair of driven feed rollers  82  and  84  preferably arranged in general vertical alignment relative to each other. In a preferred form, the feed rollers  82 ,  84  are resiliently biased into engagement with each other. During a sewing operation, the feed rollers  82 ,  84  are in continuous operative engagement with opposed sides of the material moving through the sewing station of machine  10 . As shown in  FIGS. 4 and 11 , the lower roller  82  rotates about a generally horizontal axis  86  while the upper roller  84  rotates about a generally horizontal axis  88  which generally parallels axis  86 . Preferably, each roller  82 ,  84  has an outer edge  85  ( FIG. 11 ) configured to facilitate gripping engagement with the material passing therebetween. Preferably, the outer edge  85  of each feed roller has a serrated configuration to facilitate gripping engagement with the material passing therebetween. 
         [0061]    In one form, and in the direction of material feed (as indicated by arrow  42 ), the axes  86  and  88  for the feed rollers  82  and  84 , respectively, are disposed less than one inch (1.0 inch) directly downstream or rearwardly of the fixed axis  29  of the needle bar  28 . In a preferred form, and considering the direction of material feed (as indicated by arrow  42 ), the axes  86  and  88  for the feed rollers  82  and  84 , respectively, are spaced directly downstream or rearwardly of the fixed reciprocal axis  29  of the needle bar  28  by a distance ranging between about 0.4 inches and about 1.0 inch. In a most preferred embodiment, and considering the direction of material feed (as indicated by arrow  42 ), the axes  86  and  88  for the feed rollers  82  and  84 , respectively, are spaced directly downstream or rearwardly of the fixed reciprocal axis  29  of the needle bar  28  by a distance of about 0.5 inches. 
         [0062]    In the embodiment shown in  FIGS. 2 ,  4  and  8 , the lower feed roller  82  is rotatably mounted and is primarily disposed to an underside of the work supporting surface  16  of machine  10  by a lower roller support  90  suitably secured to the base or bed portion  14  of housing  12 . In the embodiment shown in  FIG. 8 , and when mounted to the machine  10 , a portion of the peripheral edge of the lower feed roller  82  projects or extends above the work supporting surface  16  of machine  10 . In the embodiment exemplified in  FIG. 8 , a pair of rigid and laterally spaced upstanding arm portions  92  and  94  on the lower roller support  90  serve to maintain the rotational axis  86  of roller  82  vertically fixed relative to the throat plate  17   
         [0063]    Returning to  FIGS. 2 and 4 , the upper roller  84  of feed mechanism  80  is mounted by a movable upper roller support  100 . In one form, the upper roller support  100  includes a pair of spaced arm portions  102  and  104  ( FIGS. 3 and 4 ) which rigidly depend from and are commonly joined to an upstanding mounting portion  106  of the upper roller support  100 . Toward their free ends, the depending arm portions  102 ,  104  of the upper roller support  100  embrace and mount the upper feed roller  84  therebetween for rotation about fixed axis  86 . For purposes discussed hereinbelow, the upper feed roller  84  is preferably provided with an extension  87  ( FIG. 9 ) axially extending beyond the depending arm portion  104  of the upper feed roller support  100  and toward the vertical standard  18  of the machine  10 . As shown in  FIG. 4 , and toward an upper end, the mounting portion  106  of the upper roller support  100  is carried and movably influenced by a resiliently biased mechanism  110  secured to housing  12 . 
         [0064]    As shown in  FIG. 9 , mechanism  110  includes a spring  112  for continually urging the upper roller support  100 , carrying the intermittently driven upper roller  84 , into biased engagement with the lower roller  82  of feed mechanism  80 . In the embodiment shown in  FIGS. 1 and 2 , mechanism  110  further includes a selectively operated apparatus  114  for vertically raising the upper roller support  100  and thereby lifting or raising the upper feed roller  84  out of engagement with the lower feed roller  82 . In a preferred embodiment, apparatus  114  is configured to releasably maintain the upper feed roller  84  out of operable engagement with the lower feed roller  82  until mechanism  110  is purposefully conditioned such that feed roller  84  is returned into biased engagement with feed roller  82  under the influence of spring  112 . In the illustrated form, apparatus  114  is manually operated. It will be appreciated, however, apparatus could also be selectively operated by a suitable driver or solenoid without departing or detracting from the spirit and scope of the invention. 
         [0065]    As mentioned, the needle bar  28  ( FIG. 1 ) of machine  10  reciprocally moves along a fixed axis  29 . Accordingly, if the material being sewn advance or is move in the direction of arrow  42  ( FIG. 4 ) while any lengthwise portion of the needle  30  remains in the material, the likelihood of damage to the needle  30 , the needle bar  28 , and the machine  30  is significantly enhanced. 
         [0066]    In this regard, feed mechanism  80  is preferably designed to move the material through the sewing station and past the needle  30  in an intermittent fashion. Suffice it to say, the intermittently operated feed mechanism  80  is operated in timed sequence with the needle bar  28 . That is, during a sewing operation, the feed rollers  82 ,  84  of feed mechanism  80  are operated only while the needle  30  remains out of or disengaged from the material being advanced through the sewing station of machine  10 . In one form, the lower and upper feed rollers  82  and  84 , respectively, are operational for only about 35% to about 50% of the time the needle bar  28  makes one complete up and down reciprocal movement. The remainder of the time, i.e., as long as the needle  30  remains in the material, the lower and upper feed rollers  82  and  84 , respectively, of mechanism  80  do not rotate and are not effective to advance or move the material through the sewing station of machine  10 . 
         [0067]    To accomplish these desired ends, and in a preferred form, feed mechanism  80  is designed and configured with a drive system  120  ( FIG. 10 ) for intermittently and concomitantly driving the lower and upper feed rollers  82  and  84 , respectively, of mechanism  80  only while the needle  30  remains out of or disengaged from the material being advanced through the sewing station of machine  10 . The drive system  120  can take a myriad of different designs and shapes without departing or detracting from the principals of the present invention. In the embodiment shown by way of example in  FIGS. 4 ,  10  and  11 , drive system  120  includes a positively driven power train  122  for transferring rotation from the main drive shaft  24  ( FIG. 11 ) of machine  10  intermittently to each feed roller  82 ,  84  of mechanism  80 . 
         [0068]    In the embodiment illustrated in  FIGS. 10 and 11 , power train  122  includes a series of intermeshing gears operably arranged between the drive shaft  24  and the feed rollers  82 ,  84 . As shown, an input drive gear  130  is mounted for rotation or rotary movement with an elongated shaft  132 , to which gear  130  is non-rotatably secured. Shaft  132  defines an axis  134  which is fixed relative to housing  12  and generally parallels the fixed axis  26  about which the main drive shaft  24  is drivingly rotated. As schematically illustrated in  FIG. 10 , the elongated shaft  132  can be journalled by a pair of spaced bearings or bushings  136  and  138  provided within the bed portion  14  of housing  10 . 
         [0069]    Input drive gear  130  is in intermeshing engagement with gear  140 . As shown in  FIG. 4 , gear  140  is supported for rotational movement on an inverted and generally T-shaped support bracket  142 . As shown in  FIGS. 4 and 11 , gear  140  is mounted for rotary movement about an axis  144  extending generally parallel to axis  134  of shaft  132  about which the input gear  130  rotates when driven. As illustrated in  FIG. 4 , two opposed ends of the support bracket  142  are fixedly secured, as with fasteners  146  or the like, to the base or bed portion  14  of the sewing machine housing  10  whereby providing stiffness to the support bracket  142 . 
         [0070]    Gear  140  is also arranged in intermeshing engagement with gear  150 . As shown, gear  150  is supported for rotation toward another free end of support bracket  142 . As shown in  FIGS. 4 and 11 , gear  150  is supported for rotational movement about an axis  154  extending generally parallel to axis  144  about which gear  140  rotates when driven by the input drive gear  130 . 
         [0071]    As shown in  FIG. 11 , gear  150  is also arranged in intermeshing relation with a gear  160 . In one form, gear  160  is supported for rotation by the lower looper support  90  ( FIG. 4 ). Suffice it to say, gear  160  is supported for rotation or movement about an axis  164  extending generally parallel to axis  154  about which gear  150  rotates when power is inputted to the drive system  120  through input drive gear  130 . 
         [0072]    In the form shown in  FIGS. 10 through 12 , the power train  122  for transferring intermittent movement to the feed rollers  82 ,  84  of mechanism  80  can further include a gear  170  arranged in intermeshing relation with gear  160 . As shown, gear  170  forms part of a rotatable shaft assembly  172  including an elongated shaft  173  with gear  170  secured toward one end of and for rotation with shaft  173 . As shown, shaft assembly  172  defines an axis  174  extending generally parallel to axis  164  about which gear  160  rotates when power is inputted to the drive system  120  through input drive gear  130 . In the embodiment illustrated in  FIG. 12 , shaft assembly  172  is supported above the work supporting surface  16  of machine  10  by one or more suitable support brackets  176  preferably secured to the work supporting surface  16  of machine  10 . In the exemplary embodiment, shaft assembly  172  further includes another gear  178  fixed to the end of shaft  173  opposite from gear  170 . As will be appreciated from an understanding of shaft assembly  172 , and as a result of the intermeshing relationship between gears  130 ,  140 ,  150 ,  160  and  170  of power train  122 , gear  178  of assembly  172  rotates about axis  174  in response to rotational movement being imparted to the input drive gear  130  of the drive system  120 . 
         [0073]    In the embodiment of the power train  122  shown in  FIGS. 10 and 12 , gear  178  of shaft assembly  172  is arranged in intermeshing relation with gear  188  forming part of a flexible shaft assembly  182  arranged proximate to shaft assembly  172  and which is likewise supported above the work supporting surface  16  of machine  10 . In the embodiment shown in  FIG. 12 , the support bracket  176  disposed proximate to gear  178  supports both shaft assembly  172  and an axial extension  187  provided on gear  188 . In the exemplary embodiment, gear  188  is supported for rotation about an axis  184  extending generally parallel to the axis  174  of shaft  172  and which is generally aligned in a fore- and aft direction with the axis  86  of the upper feed roller  84  of roller drive mechanism  80 . 
         [0074]    Shaft assembly  182  of power train  120  transmits intermittent driving movements to the upper feed roller  84  of feed mechanism  80  in response to rotary drive movements being imparted to the input gear  130  of the drive system  120 . In the embodiment illustrated in  FIGS. 10 and 11 , shaft assembly  182  has a flexible design to allow for and accommodate vertical displacement of the upper feed roller  84  of feed mechanism  80  in response to conditioning of apparatus  114  while maintaining a positive drive connection between the input drive gear  130  of power train assembly  122  and the upper feed roller  84  of feed mechanism  80 . 
         [0075]    In the embodiment illustrated in  FIG. 12 , shaft assembly  182  further includes an elongate and flexible connector  186  operably connected to and axially extending from a free end of the axial extension  187  of gear  188 . An opposite end of the flexible connector  186  is operably connected to the axial extension  87  of the upper feed roller  84 . As will be appreciated, the flexible connector  186  of shaft assembly  182  readily allows for selective vertical manipulation and movement of the upper feed roller  84  under the influence of apparatus  114 . 
         [0076]    Returning to  FIG. 11 , and in addition to providing input drive movements to shaft assembly  172  and, ultimately, to the upper feed roller  84  of mechanism  80 , gear  160  of the drive system  120  also serves to positively drive and transmit rotary movements to gear  190  arranged in intermeshing relation with gear  160 . In one form, gear  190  is supported for rotary movement by the support  90  ( FIGS. 4 and 8 ). Preferably, gear  190  is mounted to rotate with and drive an axial extension  89  ( FIG. 8 ) provided on the lower feed roller  82 . As such, when rotation is imparted to input drive gear  130 , such rotary movements are positively transmitted through the power train  122  to the lower feed roller  82 . The relationship between the intermeshing gears of drive train  122  is such that the lower and upper feed rollers  82  and  84 , respectively, of the drive mechanism  80  are preferably driven in synchronous relation relative to each other. 
         [0077]    In one form, gear  160  is supported for rotation by the support  90  ( FIG. 4 ). Suffice it to say, gear  160  is supported for rotation about an axis  164  extending generally parallel to axis  154  about which gear  150  rotates when power is inputted to the drive system  120  through input drive gear  130 . 
         [0078]    To impart an intermittent driving action to the feed rollers  82 ,  84  of feed mechanism  80  in timed sequence or relation relative to the endwise movements of the needle bar  28 , and as shown in  FIG. 13 , an actuator  194  is provided as part of feed mechanism  80 . In a preferred form, actuator  194  includes an eccentric  196  operably secured to and rotatable with the main drive shaft  24  of machine  10 . That is, and as shown in  FIG. 13 , an outer peripheral edge  197  of actuator  194  is arranged in eccentric relation relative to the axis  26  of rotation of the main drive shaft  24 . Arranged in operable combination with and reciprocally driven by the eccentric  196  is an elongated connector  198  extending radially outward from the eccentric  196 . A free end of connector  198  is operably and articulately connected to a drive member  200 . 
         [0079]    As shown in  FIGS. 10 and 13 , drive member  200  is mounted along a lengthwise portion of shaft  132  to which input drive gear  130  of the power train  122  is operably connected in a non-rotatable relationship. In the illustrated embodiment, and as shown in  FIGS. 10 and 13 , drive member  200  includes a pair of spaced arms  202  and  204  which preferably embrace and are articulately connected to the free end of the connector  198 . As best illustrated in  FIG. 13 , arms  202  and  204  of drive member  200  radially extend away from the fixed axis  134  of shaft  132 . Moreover, the location wherein the elongated connector  198  is articulately connected to the arms  202  and  204  of drive member  202  is radially spaced from the axis  134  of shaft  132 . 
         [0080]    As illustrated in  FIG. 13 , a conventional one-way bearing clutch  210  is operably provided between shaft  132  and drive member  200 . As is well known, the one-way bearing clutch  210  readily permits drive member  200  to move or rotate relative to shaft  132  when drive member  200  is moved or rotated, as shown in  FIG. 13 , in a clockwise direction. Notably, however, the one-way bearing clutch  210  also serves to operably interconnect drive member  200  and shaft  132  when drive member  200  is rotated, as shown in  FIG. 13 , in a counterclockwise direction. 
         [0081]    As will be appreciated from an understanding of feed mechanism  80 , upon every revolution of the eccentric  196  the connector  198  is driven in opposed endwise directions. Notably, however, only pushing movement of the eccentrically driven connector  198  on drive member  200  is converted into rotation of shaft  132  about axis  134  by way of the one-way bearing clutch  210 . In turn, the rotation of shaft  132  is imparted to the input drive gear  130  of the drive system  120  and, through the power train  122 , imparts opposite rotational and intermittent driving movements to the lower and upper feed rollers  82  and  84 , respectively, of feed mechanism  80 . 
         [0082]    As will be appreciated from an understanding of the intermittently operated feed mechanism  80 , when the connector  198  is endwise pulled toward the axis  26  of the main drive shaft  24  by the eccentric  196 , drive member  200  will freely turn relative to and, thus, impart no rotational movement to shaft  132  as a result of the one-way bearing clutch  210 . As such, and although the feed rollers  82 ,  84  advantageously remain in constant contact with the material passing through the sewing station of machine  10  during a sewing operation, only an intermittent drive motion, arranged in timed relation with reciprocation of the needle  30 , will be imparted to the feed rollers  82 ,  84  of mechanism  80  during a sewing operation of machine  10 . 
         [0083]    The upper and lower feed rollers  82  and  84 , respectively, of feed mechanism  80  are each preferably provided with a serrated peripheral edge to promote engagement and advancement of the sewn material through the sewing station of machine. Such serrated peripheral edge of the rollers  82 ,  84  can inadvertently snag or otherwise grab onto the sewn material moving through the machine, thus, hindering material advancement. In a most preferred embodiment, the mattress edge sewing machine is further provided with structure  230  which, in one form, is arranged immediately adjacent to the sewing station of the machine  10 , for stripping material from and inhibiting the material from inadvertently remaining engaged with feed mechanism  80  as the material moves through the sewing station of the machine  10 . 
         [0084]    In one form, the structure  230  for stripping material from the lower feed roller  82  ( FIG. 16 ) as the material moves through the sewing station includes cooperating instrumentalities  232  on the throat plate  17  and on the lower feed roller  84  of feed mechanism  80 . In the form shown by way of example in  FIGS. 14 ,  15 , and  16 , the cooperating instrumentalities  232  includes a series of fingers or tines  234  on the throat plate  17  which extend generally parallel to the direction of material feed (as indicated by arrow  42  in  FIG. 15 ) moving through the sewing station. The series of fingers or tines  234  on the throat plate  17  are arranged in registry with an equal number of annular grooves  236  provided on the lower feed roller  82 . As such, and as shown in  FIG. 16 , the serrated peripheral edge of the lower feed roller  82  is permitted to project through the throat plate  17  to operably engage and facilitate advancement and movement of the mattress material through the sewing station of the machine with the fingers or tines  234  cooperating with the grooves  236  in roller  82  to significantly reduce if not eliminate the likelihood the sewn material, passing from the sewing station, will inadvertently remain engaged with one or both feed rollers  82 ,  84  of the feed mechanism  80 . 
         [0085]    From the foregoing it will be readily appreciated and observed that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It will be appreciated, however, that the present disclosure is intended to set forth an exemplification of the present invention which is not intended to limit the invention to the specific embodiment illustrated.

Technology Classification (CPC): 3