US1951842A - Knitting machine - Google Patents

Description

March 20, 1934. R. H. ROBINSON KNITTING MACHINE Filed Oct. 10, 1931 s Sheets-Sheet 1 March 20, 1934. RoBlNSON 1,951,842

KNITTING MACHINE Filed Oct. 10, 1931 3 Sheets-Sheet 2 IIVENTOR March 20, 1934. R, H ROBINSON 1,951,842

KNITTING MACHINE Filed Oct. 10, 1931 s Sheets-Sheet 3 Patented Mar. 20, 1934 UNITED STATES PATENT OFFICE 1,951,842 KNITTING MACHINE Application October. 10,

1931, Serial No. 568,059

In Great Britain December 10, 1930 12 Claims.

This invention consists in improvements in or relating to knitting machines and has particular reference to yarn-feeding or splicing means and to trapping or cutting devices therefor. The

invention isdesigned to be particularly applicable to machines in which warp-yarns are supplied to the needles in addition to other yarns from ground-yarn feeders or the like, but it is not limited to this application. 1

The present invention comprises the combination of a yarn-feeder and actuating means therefor comprising an intermeshing rack and'pinion (or toothed sector) one of which parts (e. g. the

pinion or sector) is operatively connected with '15. the feeder, and the rack and pinion (or sector) are so formed that during endwise movement of the rack successive teeth thereon will be engaged with successive teeth on the pinion (or 'sector).

Hitherto, a construction has been proposed in which on one side of the pivot about which a yarn-feeder was mounted to swing the end of the feeder itself was bifurcated and a lip formed on a slider engaged in the bifurcation so that as the slider moved endwise the feeder was turned about its pivot. In such a construction a fine and accurate adjustment of. the feeder to enable a close initial setting to be made is impossible and, furthermore, backlash is unavoidable. By the present invention, however, the use of a rack and pinion (or toothed sector) in which successive teeth on the rack mesh with and engage suc- :cessive teeth on the pinion (or sector) enables I In one form of the invention in-lwhich two or more interchangeable yarn-guides are employed, there is a rack and pinion for each yarn,- guide and a single'locking means, common to all the racks, is employed to hold any one ofthem in a selected position (a. g. the position in which it has moved to its associated feeder to an 'operative position). Each rack when moved to the selected position co-operates with the locking means so as first to release it from a rack or racks held by it at that time and thereafter the rack which thus releases the locking means is itself locked by that means in the selected position.

The invention also includes a, yarn-trapping device with or without a cutting device which, although it is particularly adapted for use with the yarn-feeder mechanism above described, is not necessarily limited thereto. Such a yarntrapper comprises in combination a pair of yarngripping members resiliently held towards one I another and a yarn-catcher which is movable towards and away from the needles and is guided, on its movement away from the needles, between the yarn-gripping members. The latter members may be in the form of plates and in one construction one member comprises two plates one behind the other for a purpose to be described hereinafter.

In order that the invention may be more clearly understood, a preferred example will now be described with the aid of the accompanying l0 drawings, in which-- Figure 1 is an elevation of a mechanism in cluding yarn-feeding, trapping and cutting devlces;

Figure 2 is a view looking from the left of Figure 1;

Figure 3 is a view looking from the right of Figure 1;

Figure 4 shows a detail of the device comprising yarn-feeders, their associated racks and the so locking device therefor;

Figure 5 is a schematic view illustrating the operation of the device and showing in addition a splicing yarn-feeder;

Figures 6 and '7 are perspective views illus- 35 trating parts only of the device to show clearly the operation of the trapper and cutter, and

Figures 8, 9, 10, and 11 illustrate diagrammatically in plan View the movement of the yarnoatcher relatively to the trapper-blades.

Like reference numerals indicate like parts in the several figures of the drawings.

In the form illustrated in the drawings the feeding means is constructed as an attachment to be applied to an existing knitting machine. The attachment comprises a bracket having side plates 10 to which are attached an upper plate 11 and having lower extensions 12. Between the plates 10 is secured a spindle 13 on which a plu- V rality of yarn-feeders 14 are pivotally mounted. Secured to each yarn-feeder so as to rotate with it is a pinion 15, and meshing with each pinion there is a sliding rack 16 there being as many racks as there are pinions. The racks 16 are I formed as continuaticns of flat plates 17 which are all mounted to slide side-by-side between the side plates 10. The plates 17 have abutments 18 arranged at different levels to be selectively engaged by'means of an adjustable external selector 19 between which and the racks there will be relative movement in the knitting direction. The selector 19 is adjustable in height, under the control of any desired patterning device, e. g. a pattern control drum, so as to be moved at will to engage any desired one of the abutments 18.

At the lower edge of each plate 17 there is formed a notch 20 to be engaged by the nose of a detent 21 which is urged always towards the edge of the plate by means of a coiled spring 22. The detent 21 constitutes the locking means referred to hereinbefore. The back edge 23 of each notch 20 is shaped to co-operate with the nose of detent 21, so that as the plate 1'7 is moved to the left in Figure 4 by engagement with the abutment 19, the edge 23 will first engage the nose of the detent and will press it downwardly out of engagement with the notch or notches 20 of any rack or racks held by it up to that time. When this occurs the rack or racks previously held are released and will return to the position of the two plates 17 Whose tail-pieces 18 are farthest to the right in Figure 4. Continued movement of the plate 17 that has thus released the detent 21, will permit the detent to snap intothe notch20 of that plate so as to lock and hold the plate at the limit of its movement towards the left in Figure 4, and during this movement the rack 16 of that plate will, by engagement with its co-operating pinion 15, move the associated yarn-feeder 14 from the inoperative position in which it extends upwardly to that in which it is operated and extends downwardly. The surface or edge 23 is at the end of a .recess 24 by which any plate, whengit is moved under the action of the selector 19.,

may slide almost to the full extent before tripping the .detent 21.

of the plates 17 is controlled by a compression spring 25 which exerts a spring pressure normally tending to move the plate to the inoperative position, that is, to the right in Figure 4. Each .spring is received partly in a recess in the upper plate 11, one end of the spring engaging the inner end of the recess, and the other end engaging an upstanding projection 26 extending from its associated plate 17. The invention is not limited to the spring-control of the plates 1'7, as they maybe positively returned, if desired,

from the operative to the inoperative position.

projector is in the form of aslide having a tail-- piece [28 which extends in height over all the tail-pieces 18 so that each time one of the latter is moved by the selector 19, the latter will also engage the tail-piece 28 to move the pro-- the yam-projector 27 away from the needles, that is, towards the right in Figure 1.

Attached to the main bracket of the device there is preferably a fitment comprising a bracket 31 held by screws 32 to the upper plate 11 and serving to support yarn-tensioning discs indioated generally by the reference numeral 33 and yarn-guides 34. Other yarn-guiding means shown as bent Wires 35 may also be secured to the brackets as indicated in Figures 1 and 2.

The yarn-trapper comprises a pair of gripping devices, one of which is in the form of a plate 36 and the other comprises two resilient strips 37 and 38 having downwardly-projecting extensions 39 and 40, respectively. These extensions are situated slightly one behind the other for a purpose to be referred to hereinafter. The resilience of the strips 3'7 and 38 serve to press them against the relatively rigid plate 36 to afford the resilient yarn-gripping means. The strips 37 and 38 are secured to one of the side plates 10 by means of set-screws 41, slots 42 in the strips affording a means for adjusting the positions of their extensions 39 ,and to obtain the best result.

The yarn-catcher comprises a slide plate 43 movable alongside, and in contact with the side plate 1 0 and this plate has adjustably secured to it by means of a screw 44, a resilient forwardly-directed extension 45. the outer end of which terminates in a hook 46 which can be seen most clearly in Figures 6 and '7.

In order to guide the yarn-catcher or hook 46 the trapper- plate extensions 39 and 40 have their forward edges turned outwardly away from the companion trapper plate 36. In other words, the trapper plates have relatively divergent edges presented towards the needles. The resilience of the extension-piece 45 of the yarn-catcher tends to urge it towards the trapper-plates and away from plate 3.6. The upper edge of the extension-piece 451's .at alevel in the main below the lower extremities of the extensions 39 and 40 of the trapper. The forward portion of the extension-piece 45 which terminates in the hook 46 is, however, cranked upwardly above the level of the lower extremitiesof the extensions 39 and 40, so that after the head and its extension-piece have been moved forward-1y, l. e. towards the needles, to its maximum extent, the rear vertical edge of the cranked extremity will-lie in front of the nip of the trapper--plates, whereby, when the yarn-catcher is withdrawn, it will pass between the extensions 39 and 40--and the plate 36. It will be assisted in entering thus within the nip of the trapper owing to the outward divergence of the forward edges of the extensions 39 and 40 with respect to the plates 36. When the yarn-catcher has been retracted to its maximum extent, the position shown in Figure 1, the hook 46 will lie in rear and clear of the trapper-extension 40, so that on the next forward movement it will slide over the outer surfaces of extensions 40 and 39, respectively, until the cranked .portion is again in advance of .the forward edge of the extension 39 in readiness for the next retraction.

-The trapper-plate 36 is provided with a yarnguiding nose or hook 47 beneath which the yarns will .be led'as they .are drawn into the trapper. This ,nosejor hook serves to prevent accidental displacement of the .bight of yarn that extends between the trapper and a feeder that is in the inoperative. position.

.The yarn-catcher plate 43 terminates in a tailpiece .48 that can beactuated by another pattern- 4, loo

controlled adjustable selector indicated in chain lines at 49 in Figure 1.

The operation of the device illustrated and described above is as follows: It is to be assumed that the yarn-feeder 14 shown in the lowermost position is that from which a yarn is at the moment of consideration being fed to. and taken by the needles, one of which is indicated at 50 in Figure 4. When it is required to replace that yarn by another, the selector 19 is brought to the height of the tail-piece 18 of the rack 16 that is associated with the feeder for the new yarn that is to be introduced. As the selector and the tailpiece engage with one another during the relative movement between them, the sliding plate 17 thus selected is moved to the left in Figures 1 and 4, andin so doing its rack 16 will turn the new feeder 14 anti-clockwise to bring it to the position of the lowermost feeder indicated. Movement of the plate 17, however, trips the detent 21 in the manner above described so that plate 17 which, up to that time, had been locked by the detent, will now be released and returned to the right of Figures 1 and 4 under the action of its controlspring 25. The plate 17 of the newly introduced feeder 14 will, however, be locked by the detent 21 in the operative position in the manner already indicated. a

When the selector 19 operates to move one of ithe plates 1'7 to introduce a new feeder into operation, the selector 49 also operates to move the yarn-catcher 46 forwardly towards the needles into such a position that the Withdrawn yarn will'pass into its hook as its feeder is moved from 'i the feeding to the inoperative or upward position.

In this forward movement of the yarn-catcher it passes over the outside surfaces of the trapper extensions 39 and 40, and so does not disturb the yarns already retained in the trapper. As soon I the withdrawn yarn is in the hook 46, the tailpiece 48 and selector 49 are disengaged and the yarn-catcher moves back under the action of a tension spring 51, one end of which is anchored at-52 to a side plate and the other end of which Tis anchored at 53 to the plate 43.

Itrapper-plates into contact with the cutting edge of a fixed cutter 54 adjustably secured by a screw' 55 passing through a slot 56 in the cutter and taking'into the side plate 11. The withdrawn yarn is thus cut and trapped, and it will be appreciated Ithat the construction ensures that the yarns already held within the trapper will not be accidentally released, because, in the first place, that portion of the catcher-blade which passes between thetrapper-plates wipes over those yarns already trapped, so that any unintentional disthe trapped yarns when the catcher first opens the foremost one 39. Before the rearmost one 40 is engaged by the catcher, the latter will itself have come into wiping engagement with the trapped yarns so that even for a moment although both the trapper members 39 and 40 may be the grip of the trapper.

When a thread is to be taken into operation, its appropriate feeder 14 will be moved into the feeding position, and after the needles have commenced to take the yarn the trapped end will be drawn out from between the trapper members.

The movement of the yarn-catcher relatively to the trapper-blades is diagrammatically illus-' trated in Figures 8 through 11, considered in conjunction with Figures 6 and 7. In Figures 8 through 11, the projecting head of the yarncatcher only is illustrated and it will be observed that in the normal inoperative position, as shown in Figure 8, it is behind the trapper- blades 39 and 40 and so positioned that when moved forwardly towards the needles it will pass over the outside of those blades. Figure 9 shows the catcher moving to the left towards the needles and passing over the outside of the blades as stated. Continuance of this movement brings the catcher to the position shown in Figure 10 and at this position it will engage the yarn that is to be withdrawn. Its movement is then reversed and it will be observed that the catcher has assumed a position, due to the natural re-' silience of the blade 45, at which on its return stroke to the right it will enter between the trapper member 47 and the blades 39, 40 in succession, the first part of this movement being indicated in Figure 11. It will be seen that Fig ure 7 shows the catcher in a position interme-.

diate those of Figures 8 and 9 as it is moving towards the needles, and Figure 6 shows the catcher in substantially the position indicated by Figure 11.

There may, if desired, be combined with the mechanism hereinabove described a splicing finger with its associated trapper and cutter. One such arrangement is illustrated in Figure 5 in which the splicing finger is indicated at 56 and the catcher-blades at 57. A yarn guide hook 58 is also employed in association with the splicing finger in the manner and for the purpose described in co-pending application Ser. No. 562,898. Alternatively, the splicing finger and cutter may be in the form illustrated in co-pending application Ser. No. 501,723.

The invention is applicable to circular knitting machines in which case the attachment will be so disposed that sliding plates such as 17 and 43 move substantially radially with respect to the needle and selector. The invention is not limited to this application, as it may be used with flat frame machines, in which case the sliding plates will move in a'direction substantially normal to a plane containing the needles.

Where it is stated in the specification and claims that the trapper gripping members are resiliently held towards one another it is to be understood to include not only a construction alternative to that illustrated, in which both members are resilient, but also that in which only one member is resilient as in the illustrated example.

I claim:-

1. In or for a knitting machine the combination of a yarn trapper comprising co-operating gripping members, a yarn catcher, means to move the yarn catcher between the gripping members as it withdraws the yarn and means to move the yarn catcher along a different path as it is advanced to engage theyarn.

2. In or for a knitting machine the combination of a yarn trapper comprising co-operating gripping members, a yarn catcher, means to move the yarn catcher between the gripping members catcher on the outside of one of the gripping members as it is advanced to engage the yarn.

3. In or for a knitting machine the combination of a yarn trapper comprising co-operating gripping members one of which comprises two elements disposed one behind the other inthe direction of movement of the yarn catcher, a yarn catcher movable to engage the yarn and to withdraw it into the trapper and means to guide the yarn catcher between the gripping members as it draws the yarn into the trapper.

4. In or for a knitting machine having a bed of needles and means to feed the yarn to the needles, the combination of a yarn trapper comprising co-operating gripping members presenting divergent edges towards the needles, a yarnv catcher movable towards and away from the needles, means resiliently to urge the catcher towards a position at which when it is moved towards the needles so as to be clear of the gripper it will enter between the said divergent edges on its return movement, and means to guide the catcher to pass between the trapper members as it withdraws the yarn but to travel along a dii' ferent path as it is moved to a position to engage the yarn.

5. In or for a knitting machine the combination of a yarn trapper comprising co-operating gripping members whereof one is rigid and the other is resilient and by its resilience presses against its companion member, a yarn catcher movable to engage a yarn to withdraw it between the trapper members, means to move the catcher clear of the trapper members in one direction to engage the yarn and to withdraw it between the co-operating trapper members until it is clear of engagement between them at the opposite end of its stroke, whereby on the return stroke it is free to pass over the outer surface of a trapper member.

6. In or for a knitting machine, the combination of a yarn trapper, a yarn catcher movable along one path to engage a running yarn and along another path to withdraw the yarn thus engaged to a position to be caught in the trapper and a yarn cutter presenting a cutting edge along the side of the cutter, the said cutting edge being in the path of the yarn to engage and cut the latter as it is drawn by the catcher into the trapper.

'7. In or for a knitting machine having a bed of needles and means to feed the yarn to the needles, the combination of a yarn trapper comprising co-operating gripping members one of which is resiliently pressed against another, a yarn catcher movable towards and away from the needles to be clear of one of said trapper members at both limits of its movement, saidcatcher being normally urged to a position to -enter between the trapper members, means to move the catcher to engage the yarn and to withdraw it between the trapper members until it has been moved clear of the said trapper memher, a cutter situated to engage and out the yarn during movement of the catcher in withdrawing the yarn between the trapper members and means to advance the catcher again towards the needles on the outside of the said trapper member cleared by the catcher.

8. In or for a knitting machine the combination of a yarn trapper comprising cooperating gripping members resiliently urged towards one another and a yarn catcher which is movable towards and away from the needles and is guided as it moves away from the needles between the yarn gripping members, one of said gripping members comprising two plates or strips disposed for the purpose described one behind the other in the direction of movement of the yarn catcher.

9. In or for a knitting machine the combination of a yarn trapper comprising co-operating gripping members whereof one is in the form of a plate extending lengthwise in a direction towards the needles and has an extension projecting laterally therefrom between which and the companion trapper member the yarn will be retained, and a yarn catcher in the form of a plate also extending lengthwise towards the needles and formed with a hooked extremity having a projection opposed to the lateral extension of the gripper member to comprise with that lateral extension interacting portions such that on each stroke of the catcher to and from the needles the catcher will be moved clear of the trapper memher at the end of one stroke, but will engage it on passing during the reverse stroke, and means to move the trapper member towards and from the needles.

10. In or for a knitting machine having a pair of needles and means to feed yarn to the needles, the combination of a yarn trapper comprising co-operating members, a yarn catcher movable towards and away from the needles, one of said trapper members being formed with a part extending in a direction of movement of the catcher and another part extending transversely thereto to co-operate with the catcher and being resiliently urged towards the companion trapper member, and the companion trapper member extends lengthwise in the direction of movement of the catcher to be engaged by the latter during the whole of its yarn-withdrawing movement, and -means to move the catcher between the trapper members as it withdraws the yarn and on the return stroke to move it over the outer surface of the co-operating portion of the resiliently urged trapper member.

11. In or for a knitting machine having a pair of needles and means to feed yarn to the needles, the combination of a yarn trapper comprising co-operating members, a yarn catcher movable towards and away from the needles one of said trapper members being formed with a part extending in a direction of movement of the catcher and another part extending transversely thereto to co-operate with the catcher and being resiliently urged towards the companion trapper member, and the companion trapper member extends lengthwise in the direction of movement of the catcher to be engaged by the latter during the whole of its yarn-withdrawing movement, means to move the catcher between the trapper members as it withdraws the yarn and on the return stroke to move it over the outer surface of the co-operating portion of the resiliently urged trapper member, and a hook-like yarn guide extending towards the needles from a portion of one of said trapper members that is adjacent the needle bed.

12. In or for a knitting machine, the combination of a yarn-trapper comprising co-operating gripping members resiliently urged towards one another, ayarn-catcher which is movable towards and away from the needles, and means to move the yarn-catcher between the gripping members as it withdraws the yarn and along a different path as it is advanced to engage the yarn.

ROBERT HAROLD ROBINSON.

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