US3839884A

US3839884A - Knitting machines

Info

Publication number: US3839884A
Application number: US00351323A
Authority: US
Inventors: J Flavell; K Jeffcoat
Original assignee: Courtaulds PLC
Current assignee: Akzo Nobel UK PLC
Priority date: 1972-04-26
Filing date: 1973-04-16
Publication date: 1974-10-08
Anticipated expiration: 1991-10-08
Also published as: IT980910B; CH565267A5; HK6379A; GB1418314A; BE798691A; FR2186979A5

Abstract

A knitting machine having two opposed arrays of independently operable needles and a presser foot arranged to traverse the arrays of needles in synchronism with the knitting action and to contact loops on the needles to control them in the knitting operation, the presser foot being mounted on a support so that it can move laterally of the needle arrays to adopt a favourable position between the arrays.

Description

States Patent 1 Flavell et al.,

[ KNITTING MACHINES [75] Inventors: John Flavell, Coundon, Coventry; Keith Jeffcoat, Nuneaton, both of England [73] Assignee: Courtaulds Limited, London,

England [22] Filed: Apr. 16, 11973 21 Appl. No: 351,323

[30] Foreign Application Priority Data [451 @ct, &

3,153,922 10/1964 Bram 66/64 3,685,317 8/1972 Giachetti et al. 66/64 FOREIGN PATENTS OR APPLICATIONS 619,967 4/1927 France v 66/64 340,005 9/1959 Switzerlandmn 66/64 382,361 11/1964 Switzerland n 66/64 Primary ExaminerRonald Feldbaum Attorney, Agent, or Firm-Davis, Hoxie, Faithfull 8: Hapgood [571 warmer A knitting machine having two opposed arrays of independently operable needles and a presser foot arranged to traverse the arrays of needles in synchronism with the knitting action and to contact loops on the needles to controlthem in tlte knitting operation, the presser foot being mounted on a support so that it can move laterally of the needle arrays to adopt a favourable position between the arrays.

7 Claims, 11 Drawing Figures PAIENTEDBET 81w 3,839,884

SHEET 10F 2 FIG. 1

PAIENTEBUCT 8l974 SIQUZBF 2 FIG-fl kNirTiNc MACHINES This invention relates to a knitting machine having two opposed arrays of independently operable needles and an element located between the two opposed arrays of needles and arranged to move in directions along the arrays to cooperate in the knitting action in such a way as to control loops of the fabric being knitted by holding loops on the needles down as the needles rise, so that the loops pass over the latches onto the stems of the needles. Elements serving this purpose are sometimes known as presser feet and will be so denoted in this specification. A presser foot or an associated element may also play a part in assisting knock over by pressing the knitted fabric down between the needle beds as needles cast off their loops from below.

According to the invention a knitting machine having two opposed arrays of independently operable needles includes a support mounted for movement along the arrays of needles and a presser foot mounted on the support with freedom of movement laterally of the arrays of needles.

The lateral freedom of movement of the presser foot may be achieved by pivotally mounting the presser foot on the support.

Alternatively, the presser foot or a part attached to it may be mounted for sliding movement or a combination of sliding and rocking movements on the support laterally of the needle beds. Themovement may take place on a pin or pins extending from a part of the support constituting a stop limiting movement of the presser foot. A stoplimiting movement of the presser foot away from the said part of the support may then be constituted by heads on the pins, by a plate constituting another part of the support, or by another element attached to the support.

The advantage of mounting the presser foot on its support with lateral freedom of movement is that it will then not bear hard against either needle bed during knitting but will adjust itself to a position between the beds. The support on which the presser foot is mounted need not then be so accurately located as would be necessary if the presser foot were carried on it in such a way as to be incapable of lateral movement. Merely carrying the foot at the end of a spring blade as has been previously proposed does not achieve a freedom of movement which is entirely satisfactory.

ative position extending approximately parallel to the tops of the needle beds in a V-flat knitting machine. the other presser foot will extend upwardly away from the needle beds and out of contact with any knitted fabric held on the needles of the beds. The

presser feet

31 and 32 are used alternately, in successive traverses of the needle beds by the cam box of the knitting machine.

If a presser foot does bear too heavily against one needle bed, the quality of the knitting is reduced and it may even cut the yarn.

The inventionwill be further described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a side view of two presser feet for a flat V-bed knitting machine, 1

FIG. 2 is a diagrammatic cross-sectionthrough a part of a V-flat knitting machine fitted with a presser foot, and

FIGS. 3 to 11 illustrate diagrammatically mountings for presser feet in a number of knitting machines according to the invention.

Each of the

presser feet

30 and 31 shown in FIG. 1 is formed from a single round section bar of resilient metal brazed or welded to an arm constituted by a stiff metal plate 32. The presser feet extend in opposite directions fromthe plate 32 and are in such angular rela tion to it that when one of them is brought into an ope'r- Means for mounting the presser feet so that they can be moved between operative and non-operative positions are described in US. Pat. Specification No. 3,613,401, but the present invention can also be applied to other means for mounting presser feet mounted singly, each on a separate support, and to presser feet mounted on supports arranged for movements other than pivotal movements to shift a presser foot between operative and non-operative positions.

FIG. 2 is a crosssection through a part of a V-flat knitting machine illustrating the position of an opera tive presser foot 33 between the

needle beds

34 and 35 and below the crossover point of the needles 36 and 37.

FIG. 3 is a cross-section through the uppermost parts of

needle beds

38 and 39 of a V-tlat knitting machine showing a presser foot 40 of rectangular section attached to an arm 41 depending from a support 42. The support 42 is movable to-and-fro along the needle beds of the machine in synchronism with the cam boxes, so as to carry the presser foot 40 along the arrays of nee dles in synchronism with the operation of the needles. The support 42 is also movable at the end of the traverse of the needle beds illustrated in FIG. 3 to a position which will remove the presser foot 40 from the operative position. At the end of the traverse next succeeding that illustrated in FIG. 3, the support will be moved to bring the presser foot 40 to the operative position once more. Conventional means for effecting such movements of the support 42 are known and are not described in this specification.

The arm 41 is mounted on the support 42 by means of a pivot pin 43 shown in FIG. 4 which is a side view of part of the support 42 and part of the arm 41. The pin 43 is carried by depending lugs 44 of the support 42, the, lugs being'in spaced relation and accommodating between them an upwardly projecting lug 45 on the arm 41, through a hole in which the pin 43 extends, the arm 41 being thus capable of pivotal movement on the pin. The pivotal movement is limited by abutment of

shoulders

46 and 47 on the arm at opposite sides of the lug 45 with flat lower faces of the lugs 44.

In subsequent Figures of the drawings, further mountings for presser feet providing lateral play of a presser foot on a support will be shown. The support is in each case movable in the manner of the support of FIGS. 3 and 4. The Figures are end views or side views similar to FIGS. 3 and 4. In these subsequent Figures, the same reference numerals as were used in FIGS. 3 and 4 will be used to designate like parts.

In the mounting shown in end view in FIG. 5 and in side view in FIGS. 6 and 7, the presser foot 40 is carried on an arm 41 having at its upper end two parallel, vertically extending open ended slots 66 and 67 (FIG. 7) with

circular holes

68 and 69 at their lower ends. The

holes

68 and 69 have a diameter exceeding the width of the

slots

66 and 67.

Slots

70 and 71 narrower than the

slots

66 and 67 extend from the

holes

68 and 69 further downinto the arm 41. The

slots

70 and 71 allow the portions 72' and 73 of the arm 41 to move outwardly in FIG. 7 permitting the arm to be pushed onto and removed from two

pins

74 and 75 which have a diameter exceeding that of the

slots

66 and 67 in the normal state of the arm 41. The material of the arm is sufficiently resilient to cause the

portions

72 and 73 to spring back to their normal positions after passage over the pins. The

pins

74 and 75 are an easy sliding fit in the

holes

68 and 69. The pins are secured in a lug 76 depending from the support 42 and have enlarged heads 77, the lug 76 and the heads 77 serving as stops to limit the lateral rocking movement of the arm 41 on the

pins

74 and 75.

The upper edge 78 of the arm 41 is arranged to come into close proximity to or to be in contact with a shoulder 79 on the support 42 when the arm is pushed onto the

pins

74 and 75 as far as it will go. The shoulder 79 constitutes an abutment for the upper edge of the arm against which the arm will be pushed by abnormal upward thrusts.

The mounting of FIGS. to 7 allows quick removal and replacement of the presser foot because of the detachable mounting of the arm 41 on the support 42.

In the mounting shown in end view and side view, respectively, in FIGS. 8 and 9, an arm 41 carrying a presser foot (not shown) can slide laterally on pins 116 secured to a lug 117 depending from a support 42 and engaged in holes in the upper end portion of the arm 41. The arm 41 is retained on the lug 117, and its lateral movement is limited by'the head 118 of a turnbuckle 1 19. The head 1 18 is secured to a shaft 120 having a portion adjacent the head of a larger diameter than a portion which is received in a hole in the lug 117. The shaft 120 is held in the lug 117 by a spring clip 121 secured on the end of the shaft which projects from the lug 117 on the side remote from the arm 41 and it is located on the lug by engagement against the lug of the shoulder formed on the shaft between the two portions of different diameter.

The arm 41 has a slot 122 through which the head 118 of the turnbuckle can be introduced. After thr turnbuckle has been inserted through the slot 122 and turned, as shown in FIG. 9, the arm 41 is retained on the lug 117, the head 118 of the turnbuckle and the lug 117 serving as stops to limit its lateral movement.

In the arrangement shown in end view and side view, respectively, in FIGS. and'll, an arm 41 carrying a presser foot.(not shown) is mounted for sliding and rocking movement on two pins 131 spaced apart on ahorizontal line in FIG. 11 and extending through holes in the upper end of the arm 41. The pins are fixed in I a plate 132 and extend into holes in a support 42, the

upper end of the arm 41 being thinner than the gap between the adjacent surfaces of the plate 132 and the support 42 which serve as stops limiting the lateral movement of the arm with respect to the support 42.

tain the plate firmly on the support 42. A protrusion 141 on the blade 135 has a hole to receive the head of a round headed pin 142 fixed to the support 42 and the blade is thereby locked against rotational movement once located with its arms in the slots 134. The lower part of the plate 132 is kept properly spaced from the support 42 by a pillar I45 fixed to the plate 132 and abutting against the support 42. The pillar 145 extends through an aperture in the arms 41.

The arm 41 is readily removed from the support 42 by rotating the blade 135 so that the protrusion 141 is sprung over the pin 142 to disengage the arms 139 and holes in the support 42, the blade can be rotated to bring its

arms

139 and 140 into the slots 134 to re- 140 from the slots 134. The plate 132 can then be withdrawn from the support 42 to release the arm 41.

In the presser foot mountings shown in FIGS. 6 to 11, such a degree of play of the arm 41 on its pins is allowed as to permit a lateral rocking movement of the arm. The degree of movement of'the presser foot will therefore depend on the length of the arm 41 from the presser foot to the connection of the arm to the support 42.

The degree of lateral movement allowed to the presser foot should be such as to maintain contact between the presser foot and the'knitting in order to maintain control over the knitting action by the presser foot. The degree of movement possible should not be substantially more than that required for the presser foot to touch both needle beds and should preferably be less than that in most instances.

What is claimed is:

1. In a knitting machine having two opposed needle beds with independently operable needles, a support, means for moving the support along the needle beds, and a presser foot carried, in its operative position, between the needle beds to control the loops of fabric being knitted on the needles, the improvement comprising a mounting member, said presser foot being attached to said mounting member, and connecting means attaching said mounting member to said support, said connecting means allowing said mounting member free movement in a direction laterally of the needle beds, thereby to allow said presser foot, in its operative position, lateral movement between said needle beds.

2. A knitting machine according to claim 1 wherein said mounting member is pivotally mounted on said support for movement laterally of said needle beds.

3. A knitting machine according to claim 1 wherein said mounting member is slidably mounted on said sup port for movement laterally of said needle beds.

4. A knitting machine according to claim 1 wherein said mounting member is mounted on said support to execute a combination of sliding and rocking movements laterally of said needle beds.

5. A knitting machine according to claim 4 further comprising at least one pin fixed on said support and extending laterally of said arrays of needles; said mounting member being formed with an aperture through which said pin extends to locate said mounting member and said presser foot for said sliding and rocking movement.

6. A knitting machine according to claim 5 further comprising stop members carried by said support for limiting said sliding and rocking movement of the presser foot.

, 7. A knitting machine. according to claim-5 wherein said mounting member is detachably mounted on said

Claims

3. A knitting machine according to claim 1 wherein said mounting member is slidably mounted on said support for movement laterally of said needle beds.

7. A knitting machine according to claim 5 wherein said mounting member is detachably mounted on said support.