GB2177126A - Device to select needles in knitting machines - Google Patents

Abstract

A device to select needles by means of the jacks in a circular knitting machine for the production of socks and the like goods, comprise a set of swingably mounted and spring-loaded selecting levers (3) placed opposite to the jack butts and associated with electro-magnets controlled by the control device of the machine, while the selecting levers (3) are provided with profiles (33) for radially pressing-in the jack butts and are swung by said jacks against the action of the springs to enable selection by the magnets. The invention enables reliable operation at higher speeds of knitting by providing ahead of the profile (33) cams (100, 110) with edges for axial displacement of the jacks and thus to move the selecting levers (3) to the electro- magnets (5). Levers raised by the cam (100) through the jacks are selectively retained in inoperative position or released to disengage the jacks from a raising cam (102). <IMAGE>

Description

SPECIFICATION Device to select needles The invention relates to a device to select needles by means of jacks in a circular knitting machine forthe production of socks and the like goods.

Various types of the needle selection devices are known, where swingable levers controlled by mechanical means arse used and where in the swung-out positions the levers are held by controlled electromagnets. One of known devices operates on the principle that the selecting levers are radially swingable from operational position by the action of the jacks which drive on a swinging cam.In the swung-out position they are according to the programme either held or not held byan electromagentandthey return orthey do not return into the original operational position, which causes selection of respective jacks. Further a device is known, where the selecting levers are axially swung by the action of swung-out butts of the jacks own specially shaped profiles ofthe selecting levers against the action of the torsion springs. To the other ends ofthe selecting levers are arranged selectively energized electromagnets to hold them in the position, when radial profile of the lever to press-in the butts ofthe selectors is offtheir horizontal track.When the lever is not held in raised position the lever drops back, while eventhejack butt passes through its recess. The jack butt in this case does not engage the radial profile and it is not pressed in. When the lever is held in upper position, radial profile gets in the track of the butt and presses thejack butt and thusthejack into the groove in the needle cylinder andraising ofthe jack does nottake place,thusthe respective needle is not selected.

The above mentioned devices operate reliably, but when selecting at higher speeds, with the first mentioned device there are difficulties with inertial masses and with the second device due to the impacts ofthe butts against the oblique surface ofthe selecting lever undesirableshocks and wearofthe parts can take place.

The task ofthe invention is to eliminate the above mentioned disadvantages.

According to the invention there is provided a device to select needles by means of jacks in acircular knitting machineforthe production of socks and the like goods comprising a set of swingably mounted and spring-loaded selecting levers placed opposite to the jack butts, with the selecting levers there being operatively associated respective electro-magnets controlled by the control device ofthe machine, while the selecting levers are provided with profiles for radially pressing-in the jack butts and are swung by said jacks against the action of the springs, wherein ahead of a profile for radially pressing-in the buttsof the jacks there are cams with edges for axial transfer of the jacks and thus to swing the selecting heversto the electro-magnets on an arc corresponding tothe horizontal profiles ofthe selecting levers created ahead of the profile for radial pressing-in.

The advantage of the invention is the factthat needle selection takes place reliably and without shocks even at higher speeds.

Embodiments ofthe invention will now be described, byway of example, with reference to the accompanying drawings, in which Fig. 1 is an axonometric illustration ofthe arrangement of several levers; Fig. 2 shows the arrangement ofthe cams to control the jacks and the selecting levers with illustration of the butttracks; Fig. 3 is a view of the selecting levers and tracks of the jack butts during the operation of the electromagnets and also illustrates the working end ofthe selecting lever swung by 90" when pressing-in the jack butt; Fig. 4 is a topviewof anotherarrangementofthe selecting levers and electro-magnets; and Fig. 5 shows the selecting device in Figs. 1 to 3 and the jacks in the needle cylinder.

Asmall diameter knitting machinefortheproduc- tion of socks and the like goods is provided with a needle cylinder 1 (Fig. 5), in the longitudinal tricks of which there are jacks 2 and above themfurther, not shown elements and needles, to select the needles the knittingfeedsare provided with a selecting device operatively associated with the butts 2' ofthe jacks 2.

Each jack 2 is provided with one butt 2', but at a different level from its neighbour.

Selecting levers 3 are arranged at individual levels corresponding to butts 2' of jacks 2 opposite to them.

Each selecting lever 3 is swingably mounted on a horizontal rod4 (Fig. 1). Electro-magnets 5 are operatively associated with respective selecting levers 3 and extend inwardly alternately from both sides, this being best illustrated in Fig. 1. Each selecting lever 3 is loaded by a tension spring 6, one end of which is suspended from the selecting lever 3 and the other end from a vertical bar 7.

The rods 4, electro-magnets Sand vertical bar 7 are fixed in a holder 8 of the selecting device, said holder being fixed to the plate 9 ofthe machine. in the cylinder side ofthe holder 8 there are com b-like protrusions 8' against which bear the selecting levers 3 due to the tension ofthe springs 6. Said comb-like protrusions 8' are located oppositethe vertical bar 7.

Thecylinderend of each selecting lever3is widened,whilethelowerhorizontal profile 31 (Fig. 3) of said widening is arrangedforcontactwith the butts 2'ofthe jacks2. Furtherthecylinderendofthe selecting lever 3 is provided with a lug 32 with a profile 33 to press the butts 2' ofthe jacks 2 in the tricks ofthe needle cylinder 1. The profile 33 is underthe level of horizontal profile31 and it is normal to it. Each selecting lever 3 is arranged so thatthe horizontal profile 31 is joust above the horizontal track A ofthe butt 2' ofthe jack 2 which is, or passes, in the lower position.

On the arc of the needle cylinder 1 to which corresponds the arc of horizontal profile 31 of the selecting lever 3 there are cam rings 10 and 11 (Fig. 2) to control the jacks 2, said cam rings being arranged as follows. The lower cam ring 10 is provided with a protrusion 100 with raising edge 101 to raise the lower butt 21 oftheiack 2. The upper cam ring 11 is provided with a protrusion 110with a lowering edge 111 to lowerthe butts 22 ofthejacks 2. The heights of the raising edge 101 and ofthe lowering edge 111 are the same and substantially they are such that the butt 2' of the jack 2 lifts the selecting lever3 to the associated electro-magnet 5.To this corresponds the track, or the liftandfall of the tracks A of butts 2' on the length of the horizontal profile 31 of the selecting lever 3, as illustrated in Figs. 2 and 3.

The operation of the above described device is as follows. During rotary knitting the needle cylinder 1 rotates in the direction S. The jacks 2 gradually drive on the raising edge 101 and their butts 2' which move along the tracks A, press againstthe horizontal profiles 31 of selecting levers 3 from below and swing said levers to the electro-magnets 5. The electromagnets Sare energized according to the programmme ofthe control device, or of the micro-computer of the machine and consequently certain selecting levers 3are held in said upper swung-out position. During further course the jacks2 are lowered by the edge 111 back to their original level.Those selecting levers 3 which are not held are returned back by the tension of springs 6, sothat the edges 33 of lugs 32 selecting levers 3 are placed in the way ofthe butts 2'. The profiles 33 press the butts 2' of the jacks 2 in the tricks ofthe needle cylinder 1, as illustrated in Fig. 3, and they are not raised byfurther raising edge 102 ofthe lower cam ring 10 and respective needles are not raised into the knitting feed. Those jacks 2, atwhich the selecting levers 3 remained held by electromagnets 5 then pass underthe profile 33 and are not pressed in the tricks in the needle cylinder 1. The jacks 2 are the raised by raising edge 102 and respective needles are raised into the knitting feed.By the above mentioned methodthejacks and hence the needles are selected according to the programme of the control micro-computer either to knit or not to knit.

There arevarious modifications within the scope of the invention possible. So for example instead of the single-arm selecting lever3, a double-arm selecting lever 3' (Fig. 4) swingably mounted on horizontal rod 4' can be used. The cylinder end ofthe selecting lever 3' is provided with a lug 32' with the profile 33' and before it there is again a horizontal profile. Furtherthe tension spring 6' is suspended here, the other end of the spring is suspended from the bar 7'. The cylinder end bears againstthe protrusion 8". The second arm of the selecting lever 3' is widened and inclined from the longitudinal axis ofthe selecting lever3' and the electro-magnet 5' is aassigned to its end.Inclination of the other arm is alternately with a set of selecting levers 3' once to the left and once to the right, as illustrated in Fig. 4. The rod 4' is mounted by its ends in two plates D1 and D2 screwed by screws S1 and S2 into the stand 8'.The openings in the stand 8' through which pass the ends ofthe rod 4' are larger than the diameter ofthe rod 4' so that they can move within the opening, because also the dimension ofthe diameter ofthe opening in the plate D1 and D2 through which passes the screw S1 ar S2 is largerthan the diameter ofthe screw S1, S2. Said arrangement serves for perfect postioning ofthe selecting levers 3' both to the butts 2' ofthejack2, and tothe electro-magnet 5'. The function of the selecting lever 3' is the same as thatof theselecing lever3.

Furtherthe whole selecting device can be arranged so that the whole arrangement is turned, i.e. the means illustrated in Fig. 2 would beturned by 180 .

The butts 2' would press the selecting levers 3 due to the action ofthe upper ring downwards and due to the action ofthelowerringtheywould return back in their original track. Pressed selecting levers3 would be held by electromagnets 5 again according to a programme.

Claims (6)

1 .A device to select needles by means of jacks in a circular knitting machineforthe production ofsoeks and the like goods comprising a set of swingably mounted and spring-loaded selecting levers placed opposite to the jack butts, with the selecting levers there being operatively associated respective electromagnets controlled by the control device ofthe machine, while the selecting levers are provided with profiles for radially pressing-in the jack butts and are swung by said jacks against the action ofthe springs, wherein ahead of a profile for radially pressing-in the butts ofthe jacks there are cams with edges for axial transfer of the jacks and thus to swing the selecting levers to the electro-magnets on an arc corresponding to the horizontal profiles ofthe selecting levers created ahead ofthe profile for radial pressing-in.

2. A device as claimed in claim 1, wherein the profile for radially pressing-in the butts ofthejacks and the horizontal profile are mutually perpendicular.

3. Adevicea & laimedin claim 1 or2,whereinin the arc of the needle cylinder in the place ofthe horizontal profile on the lower cam ring there isthe raising edge of the jacks and on the upper cam ring there is the lowering edge ofthelacks.

4. A device as claimed in claim 1, 2 or 3, wherein the axes of individual selecting levers are placed adjustably.

5. A device to select needles in a circular knitting machine, substantially as hereinbefore described with reference to Figs. 1,2,3 and 5 of the accompanying drawings.

6.A device as claimed in claim 5 but modified substantially as hereinbefore described with referenceto Fig. 4 of the accompanying drawings.