Take down apparatus for circular knitting machines
United States Patent Wood et al. E Apr. 1, 1975 TAKE DOWN APPARATUS FOR CIRCULAR [56] References Cited KNITTING MACHINES UNITED STATES PATENTS [76] Inventors: Gillies Wood, 44 Ingarsby Dr., 2,972,875 2/1961 St. Pierre 66/150 Evington; John Michael Klee, 141 3,668,900 6/1972 Peet 66/149 5 Luuerworth Rd, Leicester, both f 3,731,395 5/1973 Watanabe 66/l49 s UX England 3,738,123 6/1973 Mazzi 66/149 5 [22] Filed: 1973 Primary Examiner-Robert R. Mackey 21 APPL 325 05 Attorney, Agent, or Firm-Ro&#39; bert E. Burns;  
 R I t d U S A r f D t Emmanuel J. Lobato; Bruce L. Adams eae pplcalon aa [63] Continuation-impart of Ser. ,No. l67,264, July 29, [57 ABSTRACT i971, abandoned.  
  Take-down apparatus for a rotatlng cylinder circular knittin machine com rises 21 take-down duct havin 0 F g P g [3 1 orelgn zj f Data an inlet and an outlet coaxial with the cylinder of the 1970 mted Kmg om 38339/70 machine and a non-linear intermediate portion comprising a helical, cranked or multiple U-shaped pas- [gili] :JSIll 66/l4l9)0S4,b6?l/gg Sage. The take down duct is rotated in synchronism [58] Fntid 150 153 with the machine cylinder and prevents undesirable 1 0 care j twisting of the articles knitted on the machine.  
 11 Claims, 12 Drawing Figures PATENTEUAPR 874 200 SHEET 2 BF 7 PATENTED APR 1 I975 SHEET 4 BF 7 PATENTEDAPR H975 8M a0 SHEET 8 BF 7 Pi-JENTEUAPR H975 3.874.200  
 SHEET70F7 75 76 Ill mummm 73 TAKE DOWN APPARATUS FOR CIRCULAR KNITTING MACHINES This application is a continuation-in-part of our copending application, Ser. No. 167,264, filed, July 29, 1971, now abandoned.  
 FIELD OF INVENTION The invention relates to take down apparatus for ro tatable cylinder circular knitting machines for the production of seamless hose or half-hose or ladies pantyhose.  
 BACKGROUND OF INVENTION In the manufacture of seamless hose on a circular knitting machine the hose depends downwardly within the needle cylinder from the knitting needles ofthe ma chine and is drawn down by an air current through a suction take-down tube. As the cylinder rotates there is a tendency for the knitted tubular fabric of a part completed hose to twist. This is more pronounced for the longer lengths of fabric used for ladies pantiehose.  
 SUMMARY OF INVENTION It is an object of the invention to provide take-down apparatus for such machines which avoids such twistmg.  
  It is a further object of the invention to provide takedown apparatus capable of temporarily storing a partially knitted fabric tube in a space of axial length less than that of the knitted tube.  
  Accordingly the invention provides take-down apparatus for a rotatable cylinder circular knitting machine, comprising means defining a duct that comprises an entrance and an exit that are coaxial and intervening portions defining a non-linear passage which is, for example, helical, cranked or multiple U-shaped, means for mounting the duct defining means with the said entrance and exit coaxial with the axis of a circular knitting machine and means for bodily rotating the duct defining means in synchronism with rotation of the cylinder of the circular knitting machine. The duct has sufficient change of direction to have an antitwisting effect on the fabric through frictional contact therewith. The total change of direction of the non-linear portion is preferably at least 90. For example a bend of followed by a bend of 60 and then another bend of 30, (a total of 120) or a bend of 45 followed by a bend of 90 and another bend of 45 (a total of 180) so that the tube resumes its original line is sufficient, but more complicated arrangements such as a multiple U-shaped tube or a helical tube may be preferred because they provide additional storage for the fabric.  
  Alternatively the duct may be formed by a guide inside a tubular container. A helical guide surface fixedly mounted inside a metal or plastic container may define the duct. Alternatively vanes may be arranged in such a container so that the fabric passes down one section of the container, up another and down a third before emerging from the exit. Such a duct prevents the fabric from folding or becoming jumbled without interfering with any flow of air in the suction take down.  
  Such take down apparatus may be sold alone for adaptation to the modification of existing knitting machinery. Alternatively it may be sold as a complete kit of parts for such modification, including means for rotating the duct in synchronism with and in the same sense as the rotation of the needle cylinder, or may be designed as an integral part of a machine. The means for rotating the duct may be a drive from the needle cylinder or an independent drive.  
 BRIEF DESCRIPTION OF DRAWINGS The invention is illustrated by way of example in the drawings of which:  
  FIG. I is a schematic perspective view ofa take-down duct of apparatus according to the invention;  
  FIG. 1A is a schematic perspective view of a second kind of take-down duct of apparatus according to the invention;  
  FIG. 2 is a part-sectional perspective view of a takedown duct of other apparatus according ording to the invention;  
  FIG. 3 shows apparatus according to the invention incorporating the duct of FIG. 2 mounted in an operative position below the base plate ofa knitting machine;  
  FIG. 4 is a schematic elevation of a fourth kind of take-down duct of apparatus according to the inventron;  
  FIG. 5 is a schematic elevation of a fifth kind of takedown duct of apparatus according to the invention;  
  FIG. 6 is a plan view of the take-down duct of FIG. 5;  
  FIG. 7 is a schematic plan view of a sixth kind of take-down duct of apparatus according to the invenmm;  
  FIG. 8 is a schematic perspective view of the duct of FIG. 7;  
  FIG. 9 shows apparatus according to the invention incorporating the duct of FIGS. 7 and 8 mounted in an operative position below the base plate of a knitting machine;  
  FIG. 10 is an exploded perspective view of an actual embodiment of a duct like that of FIGS. 5 and 6; and  
  FIG. 11 shows apparatus according to the invention incorporating the duct of FIG. 10 mounted in an operative position below the base plate of a circular knitting machine.  
 DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 shows schematically a take-down duct in accordance with the invention comprising a helical tube 1 which is bent so that when mounted with its entrance and exit coaxial with the rotatable cylinder of a circular knitting machine and rotated in synchronism with the needle cylinder in the same sense as the fabric generated, the formation of twist in the fabric is avoided. The entrance of the tube 1 is positioned to receive the articles as they are knitted. The exit is joined by a bearing 2 with a stationary suction tube 3. Means for rotating the take-down tube 1 is not shown in FIG. 1 but can be like that of FIG. 3.  
  FIG. 1A shows a cranked take-down duct having the same effect as that of FIG. 1, comprising a tube having four bends 4 and coaxial entrance and exit portions 5.  
  FIG. 2 shows a helical take-down duct having the same effect as the tube 1 in FIG. 1. A container 10 has a helical guide surface 12 fixed therein and fast on a central tube 14. The container may be necked at the top for connection with the central tube of a circular knitting machine. The ducts of FIGS. 1 and 2 are incorporated, according to the invention, into take-down apparatus having means for mounting them with their en trances and exits coaxial with the axis of a cylinder of a circular knitting machine, and means for bodily rotating the ducts in synchronism with rotation of the cylinder of the knitting machine.  
  Such mounting and rotating means are illustrated in FIG. 3, in which the duct is similar to that of FIG. 2 except that the container 10 is shown necked at both ends. The upper necked end 16 of the container 10 is an entrance portion which is connected by a flexible coupling 18 through a bearing 19 to a stationary fabric receiving tube 20 extending centrally from the needle cylinder. The lower necked end 22 of the container 10 is an exit portion which carries a gear 24 integral therewith and rotatable in a bearing 26. The container 10 is rotated through the gear 24 being in constant mesh with a pinion 30 of a flexible drive 32 which is mounted on a shaft 34 rotatably journalled in the bearing 26. The shaft 34 is connected with the drive of the knitting machine or with a driven part, so as to drive the container 10 in the same direction and at the same speed as the needle cylinder.  
  FIG. 4 is schematic to the same degree as FIG. 1 and simply shows a take-down duct in the form of a tube 30 with two U-bends and both ends 31 and 32 in line which may be used in place of the container 10 of FIG. 3. FIG. is similarly schematic and shows a tube 40 with similar bends but folded up so as to occupy less room. A modification of this last arangement is shown in FIGS. 7 to 9 which show a container 60 having an inlet tube 61 and an outlet tube 62. The inlet and outlet tubes 61 and 62 have coaxial inlet and outlet portions and are bent so that they communicate with the interior of the container 60 at angularly offset positions. Three internal vanes or partitions are provided in the container 60, each extending radially from the axis of the container. One such vane 63, extends from the floor to the ceiling of the container; another 64, extends from the ceiling to a position above the floor; and the third, 65, extends from the floor to a position below the ceiling. The inlet tube 61 communicates with the interior of the container 60 in the sector between the vanes 63 and 64, and the outlet tube 62 communicates with the interior of the container between the vanes 63 and 65. Thus, the vanes mounted in the container 60 define a duct of generally similar shape to that of FIGS. 5 and 6.  
  FIG. 9 shows the mounting of the container 60 on a knitting machine. The needle cylinder of the machine is not shown, but a stationary tube 70 is the stationary tube conventionally located in the needle cylinder. A drive tube 71 is driven by the needle cylinder and is keyed to a pinion 72 that drives a pair of side gears 73 rotatably supported by a molded plastics sheath 74. The sheath 74 is securely mounted on a stationary part 75 of the knitting machine and houses a collar 76 mounting the stationary tube 70 and preventing its rotation. The container 60 of FIGS. 7 and 8 is mounted between cups 77a and 77b of which the upper 77a is rotatably supported by a bearing 79a and driven by the side gears 73. The lower cup 77b is rotatably mounted by a bearing 7%. The container 60 is surrounded by a stationary sleeve 78, the lower end of which is connected by a reducer 78a and flexible joint to a suction tube 100.  
  The duct of FIGS. 5 and 6 is conveniently made in five pieces as shown in FIGS. and 11, of which FIG. 11 shows preferred mounting and rotating means. The  
 five components of the duct are three linear tube portions 80, 81 and 82 positioned between an upper cap 84 and a lower cap 85. The upper cap 84 includes an entrance tube 86 communicating with tube portion and a duct 87 connecting tube portions 81 and 82. The lower cap includes an exit duct 88 communicating with tube portion 82 and a duct 89 connecting tube portions 80 and 81. The upper cap 84 is housed in a cup 90 as shown in FIG. 11 and the lower cap 85 is housed in a cup 91. The cups 90 and 91 are provided with bearings 92 and 93 mounting them at the ends of an outer cover 94 corresponding to the sleeve 78 of FIG. 9. The cover 94 is adapted to remain stationary in use when the take-down apparatus is mounted coaxially with the cylinder of a circular knitting machine (the parts of which are shown in phantom lines in FIG. 11). The drive means and mounting means are similar to those of FIG. 9, and the same reference numerals have been used in respect of identical parts.  
  It will be noted that in all of the illustrated embodiments the non-linear take-down duct defines a passage having a change of direction of more than 90. In the embodiments of FIGS. 1, 2 and 3, the change of direction is provided by the spiral configuration of the passage while in the embodiments of FIGS. 4 to 11 the change of direction is provided by a double reversal of the passage.  
  While preferred embodiments of the invention have been illustrated by way of example in the drawings and are herein specifically described, it will be understood that the invention is in no way limited to the illustrated embodiments.  
 What we claim and desire to secure by Letters Patent l. Airflow take-down apparatus for a rotatable cylinder circular knitting machine, comprising take-down duct means that comprises an entrance portion and an exit portion that are coaxial with one another and an intervening tortuous passageway having imperforate walls and presenting a continuous and uninterrupted throughway for continuous free passage of fabric there through, said passageway having such configuration and length that the shortest distance from said entrance portion to said exit portion through said throughway is substantially greater than the direct axial distance between the entrance and exit portions of said duct means, means for mounting said duct means with the said entrance portion and exit portion coaxial with the axis of a circular knitting machine, means for bodily rotating said duct means in synchronism with rotation of the cylinder of the circular knitting machine and a stationary airflow tube connected with said exit portion for conducting airflow from said passageway to continuously draw said fabric therethrough during the knitting ofa length of fabric and to draw off a length of fabric when completed, whereby said tortuous passageway provides space for accommodating a length of fabric and said airflow continuously tensions the fabric as it is being knit and accommodated in said tortuous passageway and draws off a length of fabric when it is completed.  
  2. Take-down apparatus according to claim 1, wherein said take-down duct means comprises a tubular passageway having two reverse bends between said entrance portion and exit portion.  
  3. Take-down apparatus for a rotatable cylinder cir cular knitting machine, comprising take-down duct means that comprises three linear tubular sections disposed side by side, an upper cap and a lower cap between which said tubular sections are disposed, said upper cap comprising an entrance portion communicating with the upper end of a first one of said tubular sections and a reverse bend passage connecting the upper ends of the second and third of said tubular sections, and said lower cap comprising an exit portion coaxial with said entrance portion and communicating with the lower end of said third tubular section and a reverse bend section connecting the lower ends of said first and second tubular sections, means for mounting said duct means with said entrance portion and said exit portion coaxial with the axis of a circular knitting machine and means for bodily rotating the duct means in synchronism with rotation of the cylinder of the circular knitting machine.  
  4. Take-down apparatus for a rotatable cylinder circular knitting machine, comprising take-down duct means that comprises an entrance portion and an exit portion that are coaxial with one another and an intervening tortuous passageway having imperforate walls and presenting a continuous and uninterrupted throughway for fabric having a length substantially greater than the direct axial distance between the entrance and exit portions of the duct, said tortuous passageway comprising first, second and third linear portions disposed side by side, a first reverse bend connecting adjacent ends of said first and second linear portions and a second reverse bend connecting the opposite end of said second linear portion with the adjacent end of said third linear portion, means for mounting said duct means with the said entrance portion and exit portion coaxial with the axis of a circular knitting machine and means for bodily rotating the duct means in synchronism with rotation of the cylinder of the circular knitting machine.  
  5. Take-down apparatus according to claim 1, wherein said take-down duct means comprises means defining a helical passage between said entrance portion and said exit portion.  
  6. Take-down apparatus according to claim 5, wherein said take-down duct means comprises a helically curved tube.  
  7. Take-down apparatus according to claim 5, wherein said take-down duct means comprises a cylindrical container and a helical guide in said container defining .a helical passage.  
  8. Take-down apparatus according to claim 7, wherein opposite ends of said. container are necked in to provide said entrance portion and exit portion.  
  9. Take-down apparatus according to claim 1, wherein said take-down duct means comprises a cylindrical container having opposite first and second ends, first, second and third radial partitions in said container defining sector shaped spaces, said first partition extending from one end to the other, said second partition extending to said first end and being spaced from the second end, said third partition extending to said second end and being spaced from the first end, means at said first end comprising said entrance portion opening into the space between said first and second partitions and means at said second end comprising said exit portion opening from the space between said first and third partitions.  
  10. Take-down apparatus according to claim 1, wherein said take-down duct comprises a cranked passage.  
  11. Take-down apparatus according to claim 1, wherein the total change of direction of said tortuous passageway is at least