Patent Document

FIELD OF THE INVENTION 
     The present invention relates to a tufting machine with replaceable self-aligning gauge modules and is more particularly concerned with a gauge module with individually replaceable gauge elements which can be readily installed and removed. 
     BACKGROUND OF THE INVENTION 
     Tufting machines are built with precision so that the needles and loopers of the machine are accurately spaced from each other along the needle bar or looper bars. The loopers and needles must be spaced from each other so that the looper bills pass closely adjacent to the needles to engage and hold loops of yarns carried by the needles. When assembling a tufting apparatus, errors in positioning these gauge elements may accumulate as the work progresses. The present invention seeks to establish consistency with these parts across the width of the apparatus, to provide a tufting environment, suitable even for narrow gauge configurations. The present invention also addresses the problem of replacing individual gauge elements that become broken or damaged during tufting. In most modular designs, a broken gauge element requires discarding the entire modular block containing a set of about one to two dozen gauge elements. The present invention allows for quick and efficient replacement of individually damaged gauge elements. 
     The idea of replacing individual components of assemblies in tufting machines is not new. In the past, knife holder assemblies have been devised that allow for the replacement of individual knives. The knives were arranged in pre-assembled or modular fashion in a knife holder, each knife holder having a guide mechanism which enables the knives, as a group, to be positioned on a carrying member of a tufting machine and maintained in appropriate alignment. U.S. Pat. Nos. 4,608,934; 4,669,171; 4,691,646; and 4,693,191 illustrate such prior art knife holder assemblies in which parallel knives are disposed in juxtaposition in guide bars which are provided with guides for guiding and then clamping them in appropriate positions on a tufting machine. 
     Needles have previously been individually secured in modular gauge blocks as shown in U.S. Pat. No. 4,170,949, and hooks and knives have also been individually secured in gauge parts mounting blocks as shown in U.S. Pat. No. 4,491,078. These designs have used individual clamping screws to hold each gauge element in place. These blocks were not mated with slots on the carrying members and were heavily machined. 
     More recently attempts have been made to incorporate needles and loopers into replaceable modular assemblies. U.S. Pat. Nos. RE37,108, 5,896,821, 5,295,450 illustrate such modular gauge assemblies in which the gauge elements are permanently embedded into the modular block. The block is attached to the guide bar with a single screw allowing for removal and replacement of the block. One shortcoming of these modular assemblies is that when a single gauge element breaks the entire modular assembly must be discarded. 
     SUMMARY OF THE INVENTION 
     The present invention includes a modular gauge assembly that attaches to a gauge bar. The gauge bar has a plurality of positioning recesses that allows a detent on an individual modular block to be accurately positioned along the gauge bar. Each modular block typically includes a front surface, a pair of side surfaces opposed to each other, a rear surface opposite to the front surface, and a bottom surface. A tongue, which may or may not be a part of the cast block extends from a bottom or bottom surface of the modular block. The tongue includes a threaded hole which along with a securing screw serves to mount the block to a gauge bar. The threaded hole aligns with the gauge bar receiving hole when the tongue of the modular block is positioned properly with a recess on the gauge bar. When sufficiently tightened, the securing screw holds the modular block to the gauge bar. At least the front surface contains a plurality of spaced parallel slots so that gauge elements may be positioned in the slots with proper spacing in the block. The proximal ends of the gauge elements have apertures recessed therein. The proximal ends of the gauge elements are inserted into the block and secured there by a securing pin that enters the block on one of the opposing side surfaces and passes through the apertures on the proximal ends of the gauge elements. Individual gauge elements can be replaced by demounting the affected block, removing the securing pin and removing the selected gauge element. After the selected gauge element is removed a new gauge element may be re-inserted into the proper vertical slot and secured by the securing pin. 
     A plurality of modular blocks are arranged along the surface of the gauge bar and are vertically positioned on the gauge bar by a horizontal surface on the gauge bar or on a guide bar that passes through a guide bar channel on the gauge bar. The width of each block is equal to the distance between the positioning recesses of the gauge bar so that the edges of the blocks abut one another and the blocks are laterally positioned. 
     In an alternative embodiment of the present invention the modular gauge assembly attaches to a gauge bar having a plurality of positioning recesses that allows the detent on an individual modular block to laterally position the block on the gauge bar. Each modular block typically includes a front surface, a pair of side surfaces opposed to each other, a rear surface opposite to the front surface, and opposing bottom and top surfaces. The rear surface contains a rectangular tab or detent that includes a threaded hole to receive a securing screw. The threaded hole aligns with the gauge bar receiving hole when the modular block is positioned properly on the gauge bar. When tightened, the securing screw holds the modular block securely to the gauge bar. A plurality of gauge holes extend from the bottom toward the top surface, in some cases passing through the modular block. Gauge elements with proximal ends adopted to be received within the gauge holes may be positioned with proper spacing in the block. Gauge elements that have the proximal end inserted into the block are securely positioned pin-screws that enter the block below the tab on the rear surface. The pin-screws are positioned beneath the tab. In this fashion, the pin-screws can be accessed without removing the modular block from the gauge bar. 
     Accordingly, it is an object of the present invention to provide a tufting machine where the gauge elements of the tufting machine are accurately positioned within a modular block assembly. 
     Another object of the present invention is to provide in a tufting machine, a system which can facilitate the rapid change over of one or more damaged gauge elements, reducing to a minimum the downtime of the tufting machine. 
     Another object of the present invention is to provide in a modular block assembly, a system which can facilitate the rapid change over of individual damaged gauge elements, reducing the cost of repairing broken gauge elements and removing the need to replace entire modular blocks when a single gauge element becomes damaged. 
     Other objects, features, and advantages of the present invention will become apparent from the following description when considered in conjunction with the accompanying drawing wherein like characters of reference designate corresponding parts throughout several views. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a fragmentary perspective view of a modular block assembly with single looper modular blocks in place on a gauge bar. 
     FIG. 2 is an exploded perspective view of modular block assembly of FIG. 1 with modular blocks removed from the gauge bar, and one single looper modular block disassembled. 
     FIG. 3 is a perspective view of the rear surface of a modular block of FIG.  1 . 
     FIG. 4 is a fragmentary perspective view of a double looper modular block assembly with the modular blocks in place or the gauge bar. 
     FIG. 5 is an exploded perspective view of the modular block assembly of FIG. 4, with modular blocks removed from the gauge bar and one block disassembled. 
     FIG. 6 is a fragmentary perspective view of a modular needle block assembly with the modular blocks in place on a gauge bar. 
     FIG. 7 is an exploded fragmentary perspective view of the modular needle block assembly of FIG. 6 with the modular blocks removed from the gauge bar and one block disassembled. 
     FIG. 8 is a rear perspective view of a modular block of FIG.  6 . 
    
    
     DETAILED DESCRIPTION 
     The present invention is utilized in a tufting machine of the type generally including a needle bar carrying one or more rows of longitudinally spaced needles and which is supported and reciprocally driven by a plurality of push rods. In the tufting zone, the needles carry yarns which are driven through a backing fabric by the reciprocation of the needles. While penetrating the backing fabric, a plurality of longitudinally spaced hooks cooperate with the needles to seize loops of yarns and thereby form the face of a resulting fabric. In some cases the hooks will cooperate with knives to cut the loops of yarn seized on the hooks and thereby form a cut pile face for the fabric. The present invention is directed to modular units for holding loopers or hooks and for holding needles to facilitate their cooperation during the tufting process. 
     Referring in detail to FIG. 1, a modular block assembly  5  is illustrated having a single row of gauge elements  10 , in this case loopers, housed in the modular blocks  15 . The individual gauge elements  10  are fastened to the block  15  by securing pin  20 . As better illustrated in FIG. 2, the securing pin  20  enters the modular block  15  at one of the opposing side surfaces  22   a,    22   b.  The gauge bar  25  and guide bar  30  are used in concert to position the individual modular blocks  15  relative to one another. The guide bar  30  slides laterally through channel  35  substantially the entire length of the gauge bar  25 , and engages tab breaks  115  of the modular blocks  15 , as shown in FIG. 3, to vertically align the individual blocks  15 . 
     FIG. 2 illustrates a portion of the modular block assembly  5  with the blocks  15  detached from the gauge bar  25 . The gauge bar  25  has a plurality of vertical recesses  40 . The recesses  40  are crossed by lateral channel  35  so that guide bar  30  fits between the gauge bar  25  and the rear surfaces  45  of the modular blocks  15 . Guide bar  30  creates upper face  31  and lower face  32  which are normal to the side walls of recesses  40 . Theses faces  31 ,  32  serve as restraining surfaces. One modular block  15  in FIG. 2 is disassembled and removed from the gauge bar  25  to reveal the spaced parallel slots  50  divided by vertical walls  51  located on the front surface  55  of the block for receiving the proximal ends  75  of the gauge element  10 . The proximal ends  75  of the gauge elements  10  contain apertures such as pin holes  70 . When the gauge elements  10  are positioned in the modular block  15 , the pinholes  70  align with apertures formed in side surfaces of the block such as pin opening  85 . Securing pin  20  is then inserted through the pin opening  85  in one of the opposing side surfaces  22   a,    22   b,  and the pin opening  85  for each gauge element  10  to fasten the gauge elements  10  to the block  15 . In modular blocks  15  containing only a single row of gauge elements  10 , a tongue portion  60  extends from the rear surface  45  of the modular block  15 . The tongue  60  forms the detent. The tongue  60  has an opening  90 , as shown in FIG. 3, preferably in the form of a threaded hole which aligns with another hole  100 , located in a gauge bar recess  40 , when the modular block  15  is positioned on the gauge bar  25 . Once a modular block  15  is positioned a securing screw  65  can be inserted through the opening  90  and tightened into the hole  100  on the gauge bar. A modular block  15 , once fixed in place by the securing screw  65 , is prevented from lateral and vertical movement. The screw  65  and vertical recesses  40  resist against horizontal movement while the screw and faces  31 , 32  of the guide bar  25  resist against vertical movement. The fixed position of the blocks  15  insures that the gauge elements  10  remain properly aligned during the tufting process. 
     FIG. 3 shows the rear surface  45  of a modular block  15  having a single row of gauge elements  10 . On the rear surface  45  is an elongated tab  110  that extends vertically from the top  165  of the block to the bottom of the tongue portion  60  of the block. The tab  110  has a horizontal break  115  which as previously described engages with guide bar  30  to vertically position block  15  on the gauge bar  25 . The walls of break  115  are preferably substantially planar and parallel so that a part of the rectangular cross section of guide bar  30  closely fits within the break. The lower segment of the tab  120  contains the opening  90  where the securing screw  65  enters and attaches to a receiving hole  100  in the gauge bar. 
     FIG. 4 illustrates a modular block assembly  5  having three double gauge element modular blocks  130  mounted on the gauge bar  26 . Each modular block  130  contains two gauge element rows  125 . Modular blocks  130  have two apertures such as pin openings  85   a,    85   b  that are spaced apart on the side surfaces  22   a,    22   b  of the block  130 . Unlike single gauge element blocks  15 , a portion of the double gauge modular blocks  130  rests on top of the gauge bar  26  to vertically position blocks  130 . This is accomplished by pushing the tongue  60  forward to the center of the bottom of the block  135 . 
     FIG. 5 shows an exploded view of modular block  130  containing two rows  125  of gauge elements  11 ,  12 . The gauge bar  26  in FIG. 5 has a plurality of vertical recesses  40 . Vertical recesses  40  receive tongues  60  to horizontally position blocks  130  along the gauge bar  25 . Vertical positioning is accomplished by resting part of the bottom surface of gauge blocks  130  on the top surface of gauge bar  25 . The modular block  130  in FIG. 5 is disassembled and removed from the gauge bar  26  to reveal the spaced parallel slots  50   a,    50   b  located on the front  55  and rear surface  45  of the block  130  for receiving the proximal ends  75 ,  78  of the gauge elements  11 ,  12 . The proximal ends  77 ,  78  of the gauge elements  11 ,  12  contain openings such as pin holes  71 ,  72  which when positioned in slots  50   a,    50   b  of modular block  130  align with pin openings  85   a  or  85   b,  respectively. The securing pins  20   a,    20   b  are inserted through the pin openings  85   a  or  85   b  on one of the opposing side surfaces  22   a,    22   b  and through pin holes  71 ,  72  for each gauge element  11 ,  12  to fasten the gauge elements  11 ,  12  to the modular block  130 . In the illustrated modular blocks  130  containing two rows  125  of gauge elements  11 ,  12  the tongue portion  60  of the modular block  130  extends from the center of the bottom surface  135 . The tongue  60  defines an opening  90  (not shown) which aligns with receiving holes  100 , located in the vertical recesses  40 , when the modular block  130  is positioned on the gauge bar  26 . Once the modular block  130  is positioned a securing screw  65  can be inserted through opening  90  and tightened into a threaded receiving hole  100 . The modular block  130 , once fixed in place by the securing screw  65 , is prevented from lateral and vertical movement. The fixed position of the block  130  insures that the gauge elements  10  remain properly aligned during the tufting process. 
     Referring now to FIG. 6, another aspect of the present invention depicts a modular block assembly  5  having a single row of gauge elements, in this case needles  13 , housed in a clamping modular block  140 . FIG. 6 shows four clamping modular blocks  140  attached to the gauge bar  27 . The clamping modular blocks  140  are positioned such that the lower portion  150  of the block  140  extends beneath the gauge bar  27 . This exposed lower portion  150  contains the individual clamping elements, such as screw-pins  145 , shown in FIG. 7, that hold the gauge elements  13  in place in the block  140 . The gauge bar  127  has a horizontal shelf portion  27   a  and a vertical portion  27   b  which join to form an interior right angle. 
     FIG. 7 illustrates a portion of a modular block assembly  5  with screw-pin modular blocks  140  detached from the gauge bar  25  and one block  140  disassembled. The gauge bar  27  has a plurality of vertical recesses  40  imposed on the front of the gauge bar  27 . As illustrated, the recesses  40  do not extend the entire height of the wall portion  27   b  of the gauge bar  27 . Each recess contains a preferably threaded hole  100  which receives a securing screw  65  to attach the block  140  to the gauge bar  27 . The rear surface of the modular block  45  contains a rectangular tab  160  having an opening  90 , shown in FIG. 8, which aligns with the hole  100 , located in the gauge bar vertical recesses  40 . Once the modular block  140  is positioned in the right angle between the shelf portion  27   a  and wall portion  27   b , with tab  160  received in a vertical recess  40 , the securing screw  65  can be inserted through the corresponding hole  100  in the wall portion  27   b  into the opening  90  in the rectangular tab  160  and tightened to hold the modular block  140  in place. Once fixed in place by securing screw  65 , the modular block  140  is prevented from lateral movement by the action of the tab  160  fitting with the walls of the vertical recess  40 , the screw  65 , and adjacent blocks  140 . Horizontal movement is restored by action of the screw  65  at the bottom of shelf portion  27   a  of the gauge bar  27 . The fixed position of the block  140  insures that the gauge elements  10  remain properly aligned during the tufting process. 
     FIG. 7 also depicts a disassembled clamping modular block  140  thereby revealing the spaced parallel gauge element openings  155  which extend from the top surface  165  to the bottom surface  135  of the block  140 . Openings  155  need not extend completely to the top surface  165  for satisfactory operation, however, it is convenient for manufacture. The individual needles  13  are fastened to the block  140  by dedicated clamps such as screw-pins  145  that fix individual gauge elements  10  within the block  140 . Screw pins  145  enter the block  140  at the rear surface  45  of the block  45  on its lower portion  150 . When the block is attached to the gauge bar  25  the screw-pins  145  remain accessible so that individual gauge elements  10  can be removed and replaced. 
     FIG. 8 illustrates the top  165  and rear surface  45  of the block  140 . Gauge element openings  155  can be seen on the top surface  165  of the block  140 . The rectangular tab  160  for positioning the block  140  on the gauge bar  25  is located centrally on the rear surface  45  of the block  140 . The rectangular tab  160  defines the opening  90  which aligns with the holes  100  in vertical recesses  40  and with securing screw  65  fixes the block  140  to the gauge bar  27 . Openings  170  for screw pins  145  are located horizontally along the lower portion  150  of block  140 . 
     Although a preferred embodiment of the present invention has been disclosed in detail herein, it will be understood that various substitutions and modifications may be made to the disclosed embodiment described herein without departing from the scope and spirit of the present invention as recited in the appended claims.

Technology Category: 6