US3826111A

US3826111A - Circular knitting machine suction takeup

Info

Publication number: US3826111A
Application number: US00121649A
Authority: US
Inventors: R Peberdy
Original assignee: Bentley Engineering Co Ltd
Current assignee: Bentley Engineering Co Ltd
Priority date: 1970-03-11
Filing date: 1971-03-08
Publication date: 1974-07-30
Anticipated expiration: 1991-07-30
Also published as: FR2085607B1; GB1321454A; FR2085607A1; DE2111533A1; ES389136A1; JPS544415B1

Abstract

A method and means for producing tubular knitted fabric, as for stockings, socks or pantie hose, on a rotary cylinder circular knitting machine in which the fabric on being knitted is withdrawn upwardly from the knitting level into a receiving unit which rotates with the cylinder and on completion is withdrawn downwardly through the cylinder by reverse air flow into a lower receptacle which is stationary. A switching valve operated from the machine control means is used to switch air suction from a suction generator to the receiving unit and the lower receptacle as and when required.

Description

United States Patent Peberdy [11] 3,826,111 July 30, 1974 [54] CIRCULAR KNITTING MACHINE SUCTION TAKEUP [75] Inventor: Roland Peberdy, Leicestershire,

England I [73] Assignee: The Bentley Engineering Company Limited, Leicester, England 22 Filed: Mar. 8, 1971 21 Appl. No.: 121,649

[30] Foreign Application Priority Data Mar. 11, 1970 Great Britain 11566/70 [52] US. Cl 66/14, 66/149 S [51] lnt. Cl. D041) 15/92, D04b 9/10 [58] Field of Search 66/149 S, 149 R, 150, 153,

[56] References Cited 1 UNITED STATES PATENTS 1,713,736 5/1929 Bentley 66/14 3,108,462 10/1963 Tcnconi.... 3,306,080 2/1967 Rossler 3,392,551 7/1968 Tenconi.... 3,420,075 1/1969 Grothcy.... 3,473,350 10/1969 Scheel 3,550,403 12/1970 ShieldsQ 66/150 FOREIGN PATENTS OR APPLICATIONS 1,931,970 1/1970 Germany 66/14 1,934,730 1/1970 Germany 66/149 S 1,245,519 9/1971 Great Britain 66/149 5 707,880 6/1966 ltaly 66/149 S 713,251 9/1966 Italy 66/149 R 1,411,420 8/1965 France 66/149 S 1,412,180 8/1965 France 66/14) S Primary Examiner-Wm. Carter Reynolds Attorney, Agent, or Firm-Robert E. Burns; Emmanuel J. Lobato; Bruce L. Adams [5 7] ABSTRACT A method and means for producing tubular knitted fabric, as for stockings, socks or pantie hose, on a rotary cylinder circular knitting machine in which the fabric on being knitted is withdrawn upwardly from the knitting level into a receiving unit which rotates with the cylinder and on completion is withdrawn downwardly'through the cylinder by reverse air flow into a lower receptacle which is stationary. A switching valve operated from the machine control means is used to switch air suction from a suction generator to the receiving unit and the lower receptacle as and when required.

8 Claims, 3 Drawing Figures Lima PATENTEDJUUUIQH 3,826.11 1

SHEET 2 0F 3 v FIGQ.

PATENIEDJUUOIQH 25,1- 1.1

sum

3 or 3 FIGB.

CIRCULAR KNITTING MACHINE SUCTION TAKEUP The invention is for improvements inthe production of knitted articles of footwear, the expression articles of footwear being used herein in a broad sense to include stockings, socks, three quarter hose, pantie hose and similar articles worn on the foot. The invention is concerned with the provision of a convenient procedure and means for practising it in which articles of footwear or tubular blanks for forming such articles are withdrawn from the needles of a circular knitting machine on which they are produced in a manner which offers a number of advantages which may be needed for a variety of reasons in connection with the manufacture of different articles of footwear. In general the procedure is such that tubular fabric is withdrawn from the needles in a condition of reversal which may be needed for its own sake to facilitate subsequent processing, or may be incidental to the obtaining of other advantages as will appear later.

In accordance with the invention there is provided a method of producing a tubular knitted fabric article for example a stocking, sock, pantie hose or a blank therefor, on a circular knitting machine having a rotary needle cylinder, comprising the steps of withdrawing the fabric upwardly from the needles by suction through an upstanding passageway to an upper receiving unit which rotates with the needle cylinder and, on completion of the article, sucking it downwardly by reverse air flow through the needle cylinder into a lower receptacle. By this procedure the article is delivered in a condition of reversal and if a subsequent operation such as linking or seaming is required the article is ready for the performance thereof. On the other hand, the method will enable a constricted welt-like closure to be formed conveniently as the last stage of knitting without trapping the earlier formed fabric in the constriction. Further if .it is required to produce a tubular fabric of considerable length this can readily be accommodated in the upper receiving unit which rotates with the cylinder.

The invention may be practised on a machine of the opposed needle cylinder type, by causing an article being knitted to be withdrawn from the needles upwardly by suction through the top cylinder to the upper receiving unit, and on completion to be sucked downwardly through the top and bottom needle cylinders to the lower receptacle. Conveniently the method is practised by means of an air suction system which is connected to both the upper receiving unit and the lower receptacle and is arranged to be switched to apply suction to the upper unit during the knitting procedure and then to transfer the suction to the lower receptacle when an article has been completed.

ln practising the method the air flow may be obtained by connecting the inlet and outlet of an air blower unit one to the upper receiving unit and the other to the lower receptacle, and the reversal of air flow may be secured by reversing said connection.

The invention also provides in a circular knitting machine having a rotary needle cylinder equipped with needle and needles operating mechanism for knitting tubular fabric. a fabric draw-off mechanism comprising a rotatable fabric receiving unit positioned above and driven to rotate with the needle cylinder, a fabric takeup tube leading upwardly to said receiving unit from leading to the upper receivingunit and the delivery the vicinity of the needle, a fabric delivery tube extending downwards from the needle cylinder, an air suction generator connected by piping to the said receiving unit and by other piping to the delivery tube, and a switching device for switching the connection of the air suction alternatively to the receiving unit or the delivery tube as required. The fabric delivery tube may extend to a stationary fabric receiving unit to which the piping from the switching device may be connected.

In the application of the invention to a machine of the opposed needle cylinder type, the fabric take up tube extends through the upper cylinder and the fabric receiving unit is mounted immediately above said upper cylinder. The fabric take-up tube may be coupled to the upper needle cylinder to rotate therewith and may serve to impart rotation to the upper receiving unit.

The apparatus conveniently has the switching device controlled by pattern control mechanism on the knitting machine so as to apply the air suction to the receiving box during the knitting of a fabric article and during its discharge from the needles, and to switch the air suction at aboutthe time of such discharge to the delivery tube.

Conveniently the air suction generator consists of a fan the outlet and inlet of which are connected to a switching valve which has ports connected to piping tube respectively, the valve being arranged to switch the connections from the fans so that the suction is applied alternatively to the upper receiving unit and the delivery tube. The pattern control mechanism aforementioned may be arranged to actuate means for operating the switching valve appropriately as and when required.

Previously with double cylinder knitting machines knitted fabric e.g., socks, has been drawn down through the bottom cylinder to tension and withdrawn it either by rollers, air suction or grab mechanism etc. The fabric is thereby delivered from the machine right side out and for linking or seaming it is necessary for it to be reversed and after treatment reversed a second time to bring it right side out." In order to eliminate the first of these reversing operations it has been proposed to tension and deliver socks upwards so that they are then inside out. Apparatus proposed for this purpose has included a delivery tube extending vertically from the top of the knitting machine for a sufficient distance to accommodate any required length of knitted article and extending to a receptacle at the side of the machine.

In the knitting of stockings on circular knitting machines which are organised to close the toe ends of the stockings by constricting a welt like portion of fabric it is the case that if the toe end of the stocking is produced last by an orthodox procedure with the fabric drawn off downwardly from the needles, the foot fabric becomes embraced in the closure and needs to be pulled through the constricted toe end fabric as a final step after the fabric has been cast off the needles. The need for pulling the foot part through the constriction prevents the constriction from being made as tight as is generally desirable, but on the other hand offers the advantage that an anti-run band knitted before casting off is brought to the inside of the stocking. Due to their bulkiness it has not been considered practicable to knit socks with closed toes in this way for as ordinarily produced on double cylinder knitting machines they need to be knitted from welt to toe and the difficulty of having to pull the foot through the constricted toe end is considered insuperable. The procedure of drawing the fabric upwardlyfrom the needles enables a closed toe sock to be produced and causes it final anti-run band to be on the inside of the sock. Such procedure also facilitates the production of satisfactory closed toe stocking knitted welt first. The method and apparatus provided by the invention are particularly useful in facilitating manufacture of closed toe stockings knitted welt first and also closed toe socks.

When producing hosiery for use in making up into tights or body garments, tubular fabric lengths of approximately feet are produced and difficulties arise when drawing off a tube of such length as it is necessary to prevent the fabric from twisting itself. The procedure and apparatus according to the invention are also of help in this connection as the upward withdrawal of fabric into a receiving unit which rotates with the needle cylinder or cylinders enables a considerable length of tubular fabric to be accommodated in a small volume during the knitting procedure without tending to produce any twisting of the fabric tube. Afterwards when the fabric is drawn downwardly through the needle cylinder or cylinders there is no tendency to twisting as the fabric has been cast off the needles.

Briefly described a convenient embodiment of the invention consists of a circular knitting machine for producing socks or stockings or blanks for stocking tights having situated above the needle cylinder or cylinders a hose receiving unit. Said unit revolves with the needle cylinder or cylinders and has in its upper region a foraminous barrier to restrain the hose yet allow the passage of air which during the knitting is sucked out of the top of the unit by a fan. After completion of the knitting of the article it is cast off the needles and the air flow is then reversed, the sock or blank or stocking being thereby ejected down and out through the bottom of the needle cylinder or cylinders. Preferably matters are so arranged that at the time of press-off the air flow is reversed before the entire article is sucked into the receiving unit, thus ensuring that a lead in of fabric is provided to start the fabric back down through the cylinder.

An example of a convenient apparatus and procedure in accordance with the invention is illustrated by way of example in the accompanying drawings and will now be described with reference to the drawings in which:

FIG. I is a schematic diagram in elevation of a knitting machine of the opposed needle cylinder type embodying the invention;

FIG. 2 is an enlarged detailed elevation view in central cross section of the arrangement of the cylinders and certain related parts, and

FIG. 3 is an outside elevation view of the machine showing in particular the controlling means for certain of the parts.

Referring firstly to FIG. 1 the upper and lower needle cylinders of an opposed cylinder circular knitting machine are shown at l and 2 and are supported in the normal fashion from fixed parts of the machine consisting of a top plate and bed plate diagrammatically represented at 3 and 4. Mounted on the top of the upper needle cylinder 1 and arranged to rotate with it is a receiving unit comprising a chamber 5 which has a barrier or 4 screen 6 of wire mesh or other form situated high up inside the unit preferably at its largest diameter. This barrier 6 whilst preventing an article being knitted such as a sock, stocking or blank, shown at 7, from further displacement will always allow air to flow'through it. The unit hasa journal 8 at its top end so that it can engage in a substantially airtight manner around, and freely rotate on, a stationary pipe 9. v

A suction generator consisting of a motor and fan unit is shown at 10 having an air intake pipe 11 and an air outlet pipe 12, both of which are connected to a four way'valve box 13. A third pipe leading to the valve box 13 is the previously mentioned pipe 9 which is connected to the top of the receiving unit 5. A fourth pipe 14 is connected at one end to valve box 13 and opens at its other end into a stationary receiving receptable or chamber 15 below the needle cylinders. A fabric delivery tube l6 extends from below the lower needle cylinder 2 into the receiving chamber 15. For easy removal of the knitted articles from this chamber 15 there is a trap 17 which is normally held closed by clip 18. A valve 13a in the valve box 13 has two operative positions one of which is shown in full lines in FIG. 1 and the other in chain lines. The valve is moved from one operative position to the other at the dictates of a signal from the main control drum of the machine as described later.

During the knitting of a sock the valve 13a is in the position shown in full lines in FIG. 1 causing the air flow from the fan unit 10 to pass from the chamber 15 up through the tube 16, needle cylinders 2 and 1, receiving unit 5, pipe 9 and through valve box 13 into pipe 11 to the fan unit 10. The other side of valve 13a allows a free passage of air from the fan unit 10 into the chamber 15 through the

pipes

12 and 14. This condi tion is maintained sucking upwardly the article 7 being knitted to tension it.

At the time the article 7 is being cast off the needles the valve 13a is turned to the position shown in chain lines in FIG. 1. In this position air is sucked from chamber 15 through the

pipes

14 and 12 to the fan unit 10. From the fan unit 10 air is blown through the

pipes

11 and 9 and down through the receiving unit 5, the needle cylinders l and 2 and tube 16 into the chamber 15. The air current causes the knitted article 7 to be blown down through the needle cylinders l and 2 and tube 16 into the chamber 15.

By the procedure described a tubular knitted footwear article is ejected into the collecting chambers 15 in an inside out condition so that an open toe blank is ready for seaming or linking the toe. In the case of an article made with a constricted welt-like toe closure knitted as its last operation followed by an anti-run tab, the article is ejected into chamber 15 inside-out but with the anti-run tab outside the reversed sock causing it eventually to be, as desired, on the inside of the sock.

FIG. 2 shows details of the construction and mounting of the coaxial needle cylinders l and 2 and it will be seen that the construction is in the main quite orthodox. Thus pillars 20 support the top plate 3 from the bed plate 4, and the

plates

3 and 4 carry

anti-friction bearings

23 and 24 to support the cylinders rotatably. A driving shaft 29 mounted in bearings in the bed plate 4 and top plate 3 drives the cylinders in unison through

gears

27 and 28 and gear rings 25 and 26. Other known parts shown are

cam boxes

30 and 31 for the control of the needle movements, inside sinkers 32 for the bottom cylinder, verge bits 33 for the top cylinder, and a throat tube 34 from which the takedown tube 16 depends.

An upper supporting plate 21 on pillars 22 upstanding from the plate 3 carries the receiving unit 5. The passageway leading to the latter through the upper cylinder 1 isprovided by an inner tube 35 which serves as a mounting for a ring 36 carrying-the verge bits 33, being clamped to the ring 36 by an enlarged end of tube 35 being gripped between a washer 37 and the ring 36 by screws v38. The purpose of thus mounting the verge bits 33 is to enable them to be raised bodily together at certain times by raising the tube 35 within the cylinder 1. To permit this the tube has fitted around it a ring 39 clamped at intervals by screws 40 and having at spaced points depending pins 41 which are slidable up and down in holes in the cover plate of the top cylinder indicated at 42. At other intervals around the ring 39 it is formed with downwardly directed pockets containing compression springs 43 which bear against plate 42 to urge the ring 39 and tube 35 with it in an upward direction. A lever 44 pivoted between its ends at 45 to a post 46 on a bracket 47 fixed to the top plate 3 acts to control the level of the ring 39 and tube 35. The left hand end of lever 44 as seen in FIG. 2, is forked at 48 to staddle the tube 35 with clearance therefrom and each fork arm carries a roller 49 between which and the ring 39 there is a thrust bearing 50 composed of upper and lower flat rings and intervening bearing rollers. By rocking lever 44 counterclockwise the tube 35 is lowered to bring the verge bits 33 to a low operative level, and by rocking the lever 44 clockwise the tube 35 is caused to be raised to lift the verge bits away from the operative level. The verge bits are used in the manner of sinkers for the formation of loops in the top cylinder and they are sometimes required to be moved out of action. as for instance when knitting by reciprocation occurs on needles in the bottom cylinder 2. The facility for raising and lowering the tube 35 allows for this and in all positions the tube 35 is driven by engagement of the pins 41 in the holes in the cover plate 42 of the top cylinder.

As can be seen from FIG. 2 the receiving unit 5 is mounted to rotate on an upper anti-friction bearing 51 supported by the plate 21. The journal 8 which allows it to rotate relative to the stationary pipe 9 passes through the plate 21 with-clearance and has fixed to it a ring 52 between which and the plate 21 the bearing 51 is positioned. The receiving unit is not required to move up and down with the tube 35, and accordingly the latter has its upper end slidable up and down within the lower part 53 of-the unit 5. A block 54 fixed to the inside of the part 53 engages slidably in a vertical slot 55 in the upper end part of tube 35. The engagement between block 54 and slot 55 serves to drive the receiving unit 5 in unison with the tube 35 and the cylinders 1 and 2 while permitting the up and down movement of tube 35.

The manner of operating the valve 310 and the lever 44 can be seen from FIG. 3 in which the bottom frame which carries the bottom plate 4 is indicated at 56, and parts shown also in other Figures are identified by the same reference numerals as previously. The bottom frame 56 supports a rotatable control drum 57 of orthodox construction which is racked round in known manner to bring about changes in the knitting cycle. By

studs

58, 58a and 59 on the control drum 57

levers

60 and 61 both pivoted at 62 are operated at appropriate times in the knitting cycle. The lever 60 operates a follower such as a push rod 63 or a bowden cable to control the position of lever 44 so that when a gap occurs between the cam parts 58 and 58a the lever.60 drops and allows the right hand end of lever 44 to drop under the action of the compression springs 43 which thus causes the tube 35 to be raised to a predetermined extent. When the lever 60 is again raised the tube 35 is lowered to lower the verge bits 33 to the operative level.

The valve 13a is fixed to a spindle 64 which is turned to move the valve from one to the other of its operative positions. On the spindle 64 there is fixed a lever 65 connected bya link 66 to the long arm of lever 61 (this being a bellcrank lever). The lever 65 is fitted with a return spring 67. During the knitting of an article 7 the valve 13a is held by return spring 67 in the position shown in FIG. 1 which is the full line position of the

parts

61, 65 and 66 in FIG. 3. When the article 7 is being cast off from the needles a cam such as 59 on the drum 57 rocks the lever 61 counterclockwise against the action of spring 67 to the position shown in chain lines in FIG. 3 pulling the link 66 downwardly and turning the arm 65 and spindle 64 clockwise through a right angle to bring the valve to the position shown in chain lines in FIG. 1. This causes reversal of the air flow through the receiving unit 5 and the cylinders 1 and 2 to discharge the article 7 downwardly into the container 15.

It will be understood that the invention may be applied to machines of the single cylinder or cylinder and dial type as well as to those having opposed coaxial needle cylinders..When the upper cylinder is omitted a fabric take-up tube such as 35 and receiving unit 5 are mounted coaxially with the needle cylinder and driven to rotate in unison therewith.

What I claim is:

1. In a circular knitting machine for knitting tubular fabric, the combination comprising a rotary needle cylinder, means rotatably mounting said cylinder, and fabric draw off mechanism comprising a rotatable fabric receiving unit comprising a rotatable chamber for receiving fabric drawn therein by air flow, means rotatably mounting said receiving unit above and coaxially with the needle cylinder, a fabric take up tube, means mounting said tube to lead upwardly coaxially with the needle cylinder to said receiving unit from the vicinity of the knitting level, means driving said receiving unit and take up tube to rotate with the needle cylinder, a top stationary pipe for applying suction to said fabric receiving unit to draw fabric upwardly from the knitting level into said unit, a foraminous barrier extending across said chamber of said receiving unit to permit flow of air'through said foraminous barrier to said top pipe while preventing the passage of fabric therethrough, said pipe having an end part above and coaxial with said receiving unit and a bearing journal connecting said end part to said receiving unit, a fabric collecting receptacle, a fabric delivery tube extending downwards from the needle cylinder to said collecting receptacle, an air suction generator having inflow and outflow ports, an air flow reversing valve having intake and return ports and two further ports interchangeably connectable to said intake and return ports, piping connecting said intake and return ports respectively to the outflow and inflow ports of said air suction generator, means connecting said two further ports of the reversing valve respectively to said top stationary pipe and to said collecting receptacle, and means for operating said valve in timed relation to programming of said knitting machine to apply suction through said top stationary pipe to said receiving unit during the knitting of a piece of fabric to draw said fabric from the knitting level into said receiving unit as the fabric is being knit and to store it in said receiving unit until the knitting of a piece of fabric is completed whereupon said valve is reversed to apply suction to said collecting receptacle to draw said piece of fabric out of said receiving unit and through said take-up tube and said delivery tube down I into said collecting receptacle.

2. The combination as claimed in claim 1, wherein the collecting receptacle is stationary.

3. The combination as claimed in claim 1 in a machine of the opposed needle cylinder type having a lower cylinder and an upper cylinder, wherein said needle cylinder is the lower cylinder of the machine and the mounting means for the fabric take up tube comprises the upper needle cylinder through which the take up tube extends, and wherein the fabric receiving unit is mounted immediately above said upper cylinder.

4. The combination as claimed in claim 3 including a carrier mounted on the lower end of the fabric take up tube to support verge bits at positions interposed between needle tricks in the upper needle cylinder, and means for raising and lowering said carrier to raise and lower the level of verge bits thereon.

5. The combination as claimed in claim 4 in which said driving means includes means coupling the receiving unit rotationally to the take up tube whilst permitting up and down sliding movement between them, and mechanism actuable from patterning means at required times to raise and lower the take up tube and with it the verge bit carrier.

6. The combination as claimed in claim 1, wherein said rotatable chamber has a portion of larger diameter than said take up tube, said foraminous barrier extending across said chamber at said portion of larger diameter.

7. The combination as claimed in claim 1, wherein said rotatable chamber has a lower portion with upwardly diverging walls and an upper portion with upwardly converging walls.

8. The combination as claimed in claim 7, wherein said foraminous barrier comprises a screen extending across said chamber between said upper and lower por-

Claims

1. In a circular knitting machine for knitting tubular fabric, the combination comprising a rotary needle cylinder, means rotatably mounting said cylinder, and fabric draw off mechanism comprising a rotatable fabric receiving unit comprising a rotatable chamber for receiving fabric drawn therein by air flow, means rotatably mounting said receiving unit above and coaxially with the needle cylinder, a fabric take up tube, means mounting said tube to lead upwardly coaxially with the needle cylinder to said receiving unit from the vicinity of the knitting level, means driving said receiving unit and take up tube to rotate with the needle cylinder, a top stationary pipe for applying suction to said fabric receiving unit to draw fabric upwardly from the knitting level into said unit, a foraminous barrier extending across said chamber of said receiving unit to permit flow of air through said foraminous barrier to said top pipe while preventing the passage of fabric therethrough, said pipe having an end part above and coaxial with said receiving unit and a bearing journal connecting said end part to said receiving unit, a fabric collecting receptacle, a fabric delivery tube extending downwards from the needle cylinder to said collecting receptacle, an air suction generator having inflow and outflow ports, an air flow reversing valve having intake and return ports and two further ports interchangeably connectable to said intake and return ports, piping connecting said intake and return ports respectively to the outflow and inflow ports of said air suction generator, means connecting said two further ports of the reversing valve respectively to said top stationary pipe and to said collecting receptacle, and means for operating said valve in timed relation to programming of said knitting machine to apply suction through said top stationary pipe to said receiving unit during the knitting of a piece of fabric to draw said fabric from the knitting level into said receiving unit as the fabric is being knit and to store it in said receiving unit until the knitting of a piece of fabric is completed whereupon said valve is reversed to apply suction to said collecting receptacle to draw said piece of fabric out of said receiving unit and through said take-up tube and said delivery tube down into said collecting receptacle.

8. The combination as claimed in claim 7, wherein said foraminous barrier comprises a screen extending across said chamber between said upper and lower portions.