Patent Publication Number: US-3875765-A

Title: Knitting machine apparatus for reclosing unintentionally opened latch needle hooks

Description:
United States Patent 11 [111 Fornes et al. Apr. 8, 1975 [5 1 KNITTING MACHINE APPARATUS FOR T0 6327 Zr) 2 3 gerry 0.] &#34;6.&#34; 616/9)? 10.3.8.8 l9 6 ommers eta... 6/1  
  E g z z iz r g g gg OPENED 2.066.440 l/l937 Winter et all i 66H l3 LA C E 3.093.986 6/1963 Baker 66/90 [75] memo: f ig&#39; f gf y FOREIGN PATENTS OR APPLICATIONS 132.482 9/1879 France 66 97 [73] Ass1gnee: Institute of Textile Technology,  
 Chuflmmswue Primary E.\&#39;uminerJames Kee Chi [22] Filed: June 6, 1972 Attorney, Agent, or FirmPennie &amp; Edmonds Appl No.: 260.280  
  52 us. Cl. .6 66/90; 66/8; 66/97; 66/113 511 im. Cl D04b 35/00 58 Field 6: Search 66/90, 113. s, 100. 103. 66/97 [56] References Cited UNITED STATES PATENTS 421,9l5 2/[890 Dow 6. 66/3 [57] ABSTRACT An improved knitting machine is disclosed wherein a pair of specially constructed reforming rolls is provided. Each needle hook of the knitting machine is periodically brought into operative relation with respect to these rolls such that a hook which is spread or opened beyond the correct width is automatically reclosed to its proper width by the action of the reforming rolls.  
 12 Claims, 5 Drawing Figures FIG.  
 PATENTEDAPR 819. 5  
 man 1 or 2 FIG. 2  
 PATENTEU 8|975 3.875.765  
 SHEET 2 0F 2 KNITTING MACHINE APPARATUS FOR RECLOSING UNINTENTIONALLY OPENED LATCH NEEDLE HOOKS BACKGROUND OF THE INVENTION In knitting machines of the type which employ latch needles in the knitting operation, the needle hook often exhibits a tendency to become opened and spread. Such defective hooks may result in an improperly formed loop in the knitted fabric thus producing streaks in the finished fabric. In addition, the useful life of hooks which have become defective due to spreading is less than those that maintain proper hook width. Excessive spreading or opening of the hooks usually is due to slubs, gouts, or knots in the yarn which become jammed into the open hook during machine operation causing undesirable spreading of the hook. Defective hooks of this type are usually detected visually while turning the knitting machine by hand or by checking the defects produced in the knitted fabric.  
  Present practice, say with circular sinker top knitting machines. is to reneedle or replace defective needles with hooks having the correct hook width. No practical means are known which will continually monitor and detect individually defective open hooks.  
 SUMMARY OF THE INVENTION A circular sinker top knitting machine wherein the needles thereof have their hook-ends passing between a pair of reforming rolls, such rolls being arranged perpendicular to and tangent to the circular path of the needles. Such rolls are preset with their surfaces spaced apart to correspond to the proper hook width of the knitting needles and, therefore, cause each needle in the machine to have its hook reformed to the proper gauge width as frequently as once per revolution of the machine cylinder. The reforming rolls can also be used in non-circular knitting machines to avoid continuing the use of needles with unintentionally opened hooks.  
 BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS FIG. I is a view principally in vertical section through the cylinder and top ofa circular knitting machine having the open hook correcting arrangement of the invention, and with parts shown in elevation;  
  FIG. 2 is a sectional view taken on line 2-2 of FIG. I in the direction of the arrows:  
  FIG. 3 is a fragmentary plan view of the right-hand portion of FIG. I with a part partially cut away for clarity;  
  FIG. 4 is a vertical sectional view taken essentially on line 44 of FIG. I in the direction of the arrows, and  
  FIG. 5 is a fragmentary elevational view showing a modification.  
 DETAILED DESCRIPTION Referring to the drawings. the needle cylinder II is supported for rotation relative to the machine frame I2 and relative to section blocks 13 which are fixed to the frame and sustain needle raising cams I4 and stitch cams 15 which operate upon the butts I6 of the needles 1? so as to reciprocate these latch knitting needles 17 each having a hook I8 and arranged to slide vertically in conventional needle slots 19 in the needle cylinder ll.  
  Needle cylinder 11 in which the vertical needle slots I9 are equally spaced has, secured around the internal periphery thereof, a sinker rest ring 20 formed with a flat planar sinker supporting surface 21 upon which the under surfaces of the forepart of the sinkers 22 bear. Sinker rest ring 20 is formed with a depending annular flange 23 adapted to locate the sinker rest ring concen trically atop the needle cylinder 11.  
  Fixed to the machine frame 12 surrounding the rotat able needle cylinder 11 is a stationary carrier ring 24 to which is secured a sinker cam ring 25. Beneath sinker cam ring 25 is a slotted sinker rest ring 26 which supports the shanks 26a of sinkers 22. The slots of the sinker rest ring 26 divide, more or less evenly, the distance between needle slots 19 of the needle cylinder II in order to allow proper intermeshing, without touching of all needles and sinkers. The butts of sinkers 22 are embraced between a cam shoulder 27 formed on the sinker cam ring 25, and sinker cam members 28, whereby as the sinkers are rotated with the sinker rest ring 26, the sinker earns 28 cause the sinkers 22 to reciprocate radially between the intervals between the upper portions of needles 17 relative to needle cylinder 11 and sinker rest ring 20.  
  With the present embodiment of the invention. timed interrelated movements are imparted to the needles I? and sinkers 22in conventional fashion. The needle raising cam 14 elevates needles I? as illustrated in FIG. 1 until their hooks 18 are above the upper edge of sinkers 22.  
  Two forming rolls 30 and 31 having smooth cylindrical surfaces somewhat wider or thicker than the depth of hooks 18 are supported essentially in the same plane and on parallel supporting shafts 30a and 31a. Rolls 30 and 31 are supported at an appropriate distance above the upper edge of sinkers 22 so that when needles I7 are elevated by raising cam 14 hooks 18 may enter between the cylindrical surfaces of rolls 30 and 31 at their point of closest spacing and with the loop of the hook parallel to the connecting line between the centers of the forming rolls.  
  Forming rolls 30 and 31 are located essentially at the point of one ofthe yarn feeds to the needles on cylinder 11, the yarn feed at this position being omitted. Needle cam 14 raises the needles sufficiently to place the hooks of several of them, for example 3 as shown in FIG. 4, at the operating level of the two forming cams 30 and 31. As the needles continue their forward motion caused by the rotation of needle cylinder 11 their respective hooks l8are moved between the approaching surfaces of the forming rolls. In the construction shown these rolls are mounted so as to be free turning. They are rotated by the frictional engagement of hooks 18 with the forming roll surfaces, and if the width of the hooks is excessive, each hook will be compressed and bent to its proper dimension. Then as the needles continue to be rotated by the needle cylinder they will be returned to their former position by means of cam 14 (FIG. 4). Thereafter the stitch earns 15 will cause the needles to carryout their conventional knitting operations. The camming and squeezing action will occur smoothly even if the needle cylinder 11 is turned slowly, and will perform likewise when the knitting needles 17 are moving between the forming rolls 30 and 31 at the rate of 25,000 needles per minute or faster.  
  As indicated above the needle cylinder 11 carries the needles between the forming rolls 30 and 31 and after the gauging and/or correcting action thence to the next feed where a conventional raising cam will elevate all needles to the normal operating position and the prescribed knitting action with all needles, including those corrected, will resume. This corrective action is available whether utilized or not for each and every needle once per revolution of the needle cylinder 11. Collectively. the maintenance of correct hook openings in all the knitting needles in the cylinder materially assists in the making of a uniform knit fabric with no vertical wale lines due to incorrect open hook dimensions.  
  Forming cams 30 and 31 are supported in their freely rotatable and adjustable position by means of the con struction shown at the upper portion and lefthand portion of FIG. 1. Shafts 30a and 31a of these rolls are fixed to a horizontal supporting block 36 which is mounted on a horizontal extension bar 35, for example by screws shown in FIG. 1. Bar 35 is horizontally adjustable in order to locate forming rolls 30 and 31 in proper relation to the rotating needle cylinder 11. Extension bar 35 can be shifted horizontally with respect to a cooperating supporting arm 34 which is secured by means of a split collar 33 vertically adjustable on a supporting post 32 (FIG. 2) mounted on the frame 12 of the knitting machine. Extension bar 35 is slidable in a locking groove in arm 34, the two parts being held to gether in adjusted position by means of connecting screws 34a.  
  Shaft 30a for forming roll 30 consists of the smooth portion ofa screw, the inner end of which is in threaded engagement with a hole in block 36. It is important to be able to adjust the distance separating the peripheries of the two forming rolls 30 and 31 to correspond with the dimension of the hooks used in any particular knitting machine. Accordingly the shaft 310 of forming roll 31 and on which this roll turns is provided with an eccentric stud 37 having a threaded nut on its outer end. The adjustment between the two rolls is made by turning the eccentrically mounted shaft 31a, after which the nut is tightened.  
  While the presently preferred form of the invention shows no positive drive for the forming rolls it is within the scope of the invention that such means can be provided.  
  Referring to FIG. the corrective action may be more positively implemented in another way as shown in this figure. Forming roll 31c and eccentric shaft 31b are substituted for the parts 31 and 31a respectively. The forming roll 31c has special teeth or detents 38 cut on its lower surface portion 39 of equal circular pitch to match that of the needle slots in the needle cylinder 11. The upper portion of the forming roll 31(&#39; is plain like that shown in FIG. 1. The backs of the upper portion of a needle 17 will engage in nested fashion the teeth or detents of forming roll 31c as the needles are forced upward by the raising cam 14 to bring their hooks 18 between the forming rolls and 31c. With this arrangement any tendency of the hook to twist from the pressure of the forming rolls is avoided.  
 We claim:  
  1. In a knitting machine including an array of needles with hooks at their upper ends and a mechanism for causing said needles to reciprocate to perform the knit ting operation, the improvement in combination therewith which comprises:  
 a. a pair of spaced forming cams for reforming unintentionally opened latch needle hooks to the proper gauge width, said forming cams being mounted on either side of the path described by the needle stroke between which the needle hook is adapted to pass, said forming cams being spaced apart by a distance equal to the desired width of said hooks and configured to co-act simultaneously with opposite sides of each hook.  
  2. The improvement according to claim 1, wherein at least one of said forming cams is a roll, said roll being mounted for rotation.  
  3. In a knitting machine including an array of needles with hooks at their upper ends and a mechanism for causing said needles to reciprocate to perform the knitting operation, the improvement in combination therewith which comprises:  
 a. a pair of spaced forming rolls for reforming and reclosing unintentionally opened latch needle hooks to the proper gauge width;  
 i. said forming rolls being mounted for rotation on either side of the path described by the needle stroke between which the needle hook is adapted to pass;  
 ii. said forming rolls being spaced apart by a dis tance equal to the desired width of the hook; and  
 iii. said forming rolls having smooth cylindrical surfaces the thickness of which is greater than the needle hook length.  
  4. In a knitting machine, including an array of needles arranged on a rotatable needle supporting cylinder, said needles having books at their upper ends and a mechanism for causing said needles to reciprocate to perform the knitting operation, the improvement in combination therewith which comprises:  
 a. a pair of spaced forming rolls for reforming and reclosing unintentionally opened needle hooks to the proper gauge width;  
 i. said forming rolls mounted for rotation on either side of the path described by the needle stroke between which the needle hook is adapted to pass;  
 ii. said forming rolls being spaced apart by a distance equal to the desired width of the hook;  
 iii. said forming rolls being disposed at a predetermined position relative to the path described by the needles during the rotation of the cylinder; and  
 iv. said forming rolls being mounted for free rotation such that the forming rolls are caused to rotate as the hooks pass between and frictionally engage the rolls during rotation of the cylinder.  
  5. The improvement according to claim 4 including means for adjusting the position of the forming rolls in a radial direction relative to the needle cylinder.  
  6. The improvement according to claim 5 including means for adjusting the position of the forming rolls in a direction parallel to the axis of the needle cylinder.  
  7. The improvement according to claim 6 wherein the forming rolls are so supported that the line joining the centers of said rolls is at right angles to the circular path of the needles.  
  8. A knitting machine according to claim 1 wherein said roll is provided with a series of slots extending around the periphery thereof for receiving a portion of the needles as they pass between said said forming cams.  
  9. A knitting machine according to claim 7 wherein at least one of said forming rolls is provided with a series of slots extending around the periphery thereof for receiving a portion of the individual needles as they pass between said rolls.  
  10. In a knitting machine including an array of needles with hooks at their upper ends and a mechanism for causing said needles to reciprocate to perform the knitting operation. the improvement in combination therewith which comprises:  
 a. a pair of spaced forming rolls for reforming unintentionally opened latch needle hooks to the proper gauge width, said forming rolls mounted for rotation on either side of the path described by the needle stroke between which the needle hook is adapted to pass at a section in the knitting machine where a knitting operation is not being performed, said forming rolls being spaced apart by a distance equal to the desired width of the hook.  
 12. In a knitting machine including an array of neetentionally opened latch needle hooks to the 10 dles with hooks at their upper ends and a mechanism proper gauge width, said forming rolls mounted for rotation in the same plane on either side ofthe path described by the needle stroke between which the needle hook is adapted to pass, said forming rolls being spaced apart by a distance equal to the desired width of the hook and configured to co-act simultaneously with opposite sides of the hook. 11. In a knitting machine including an array of needles with hooks at their upper ends and a mechanism for causing said needles to reciprocate to perform the knitting operation, the improvement in combination therewith which comprises:  
 a. a pair of spaced forming rolls for reforming uninfor causing said needles to reciprocate to perform the knitting operation, the improvement in combination therewith which comprises:  
 a. a pair of spaced forming rolls for reforming unintentionally opened latch needle hooks to the proper gauge width;  
 i. said forming rolls being mounted for rotation on either side of the path described by the needle stroke between which the needle hook is adapted to pass; and  
 ii. said forming rolls being spaced apart by a distance equal to the desired width of the hook