GB2079793A

GB2079793A - A knitted fabric expander for circular knitting machines

Info

Publication number: GB2079793A
Application number: GB8116247A
Authority: GB
Original assignee: Kombinat Textima VEB
Current assignee: Kombinat Textima VEB
Priority date: 1980-06-23
Filing date: 1981-05-28
Publication date: 1982-01-27
Also published as: FR2485049A1; GB2079793B; FR2485049B1; DD151190A1; DE3112181A1

Abstract

The expander comprises a supporting element 1 on which are mounted two spreading elements 6 and two upright plate-like guide elements 11 serving to guide the fabric to the take-off rollers 2. The spreading elements 6 are preferably bent in the form of an irregular half hexagon or octagon and are adjustably fixed on a mounting plate 3 which is vertically adjustable on the supporting element 1. The elements 6 together form a substantially closed loop which is disposed in a plane parallel to the plane of the take-off rollers 2. Each element 11 is adjustably connected to a bearing 8 which is adjustably secured to the supporting element 1. The pins 9 are provided with an apertured fork 12 which engages an edge portion of the respective guide element 11. The elements may be rigidly mounted on the forks or there ma be a pivotal mounting which, in conjunction with tensioning device. 19, 19' and tension springs 18, 18' allows automatic control of the guiding action of the guide elements 11. <IMAGE>

Description

SPECIFICATION Knitted fabric expander for circular knitting machines, more particularly body fabric circular knitting machines This invention relates to a knitted fabric ex pander for circular knitting machines, more particularly body fabric circular knitting ma chines, which comprises a supporting element on which are mounted spreading elements and guide elements for respectively maintaining the fabric in expanded condition and for guiding it to following fabric take-off rollers.

An expander for knitted fabric is known in which the spreading elements are arranged parallel with the fabric take-off rollers ("Ugarische Textiltetechnik"(= "Hungarian textile technology"), No. 5/67, pp. 218 to 225).

A disadvantage of such expander is that the shape of the spreading elements forms a square whose corners lie parallel with the take-off rollers, as a result of which the corners of the square act on the knitted fabric on the side of its maximum tensioning. Distortions take place in the courses of the knitted fabric, which may be spiked and therefore holed.

In another construction (Federal German Patent Specification 1 228021), in which the spreading elements are arranged transversely of the take-off cylinders, short, adjustable guide elements are disposed in a bearing on the spreading elements.

A disadvantage of such arrangement is that the guide elements take over the guiding of the knitted fabric only below the spreading elements, so that the knitted fabric is guided only to a limited extent as far as the fabric take-off rollers. Due to the uneven loading of all the knitting needles over the periphery of the needle cylinder, needle breaks occur and it is possible only to a limited extent to increase the speeds or to use this arrangement on body fabric circular knitting machines of high feeder number and fineness.

It is therefore an object of the invention to reduce needle head breakages, to increase speeds and to guarantee the quality of the knitted fabric by reducing thread distortions, more particularly in body fabric circular knitting machines of high feeder number and fineness.

The invention thus aims at providing an expander which by a coarse control of the spreading elements and a fine, preferably automatic control of the guide elements guarantee uniform tensile stress over a wide adjustment range duing the guiding of the knitted fabric from a circular cross-section to a flat one.

Accordingly, the present invention consists in a knitted fabric expander for circular knitting machines, more particularly body fabric circular knitting machines, which comprises a supporting element on which are mounted spreading elements and guide elements for respectively maintaining the fabric in ex panded condition and for guiding it to fabric take-off rollers, wherein two spreading ele ments which are preferably bent in the form of an irregular half hexagon or octagon are adjustably fixed by clamping screws on the supporting element and a mounting plate and are located palrallel with the fabric take-off rollers, and wherein two guide elements adjustable by clamping screws are mounted on the supporting element and in a bearing between the spreading elements.

A constant tensile stressing of the knitted fabric by the expander is conveniently obtained in that the top ends of the guide elements are located above or in the plane in which the spreading elements are located.

Advantageously, the fine control of the guide elements is achieved in that the guide elements are formed with bores which receive pivot pins which connect the guide elements to the supporting element via pins having a forked end cooperating with the pivot pin.

Automatic control of the guide elements is preferably guaranteed in that bores are provided at both the top and bottom ends of the guide elements in which respective springs are anchored to extend between said guide elements. Preferably the guide elements have a constant or downwardly tapering thickness.

The invention provides an expander which makes possible coarse regulation of the sliding guidance between expander and the knitted fabric by the spreading elements, and fine, preferably automatic regulation by the guide elements in a pivotable manner, with or without spring and with a large adjustment range.

rhe arrangement of the top ends of the guide elements above or at the same height as the plane in which the spreading elements are arranged also ensures a uniform loading of all the latch needles on the periphery of the needle cylinder, as a result of which needle breakages and the distortion of the courses in the fabric are reduced, and moreover speeds can be increased due to the reduction of the tensile stress during the whole width formation, so that the expander can be used for body fabric circular knitting machines of high feeder number and fineness.

In order that the invention may be more readily understood, reference is made to the accompanying drawings which illustrate diagrammatically and by way of example an embodiment thereof, and in which: Figure 1 shows a perspective view of the expander according to the invention, and Figure 2 is a plan view of the expander, cross-sectioned on the line A-A of Fig. 1 A supporting element 1 is attached to a dial pin (not shown) of a circular knitting machine.

Take-off rollers 2 for the knitted fabric are arranged below the supporting element 1. A mounting plate 3 is attached by means of clamping screws 4 to the supporting element 1, so that the plate 3 can be vertically adjusted. Fabric spreading elements 6 are attached via cranked rod 5 to the fastening plate 3 by means of clamping screws 7. The cranking of the rods 5 makes the spreading elements 6 exchangeable. Width adjustability is made possible by the clamping screws 7.

Pins 9 are adjustably secured in a bearing 8 by means of clamping screws 10. Mounted on the pins 9 are upright fabric guide elements 11 whose top ends are above or at the same level as the plane in which the spreading elements 6 are disposed. Each pin 9 has a fork 1 2 with a bore 1 3. In a first embodiment (as illustrated) each fork 1 2 is rigidly connected to the respective guide element 11 via a screw and check nut assembly 14 which is received in a bore 1 5 in the guide element 11. If this rigid construction is exclusively required, the pins 9 are rigidly connected to the guide elements 11, for example by welding, and the forks 1 2 are dispensed with.In a resilient, self-regulating embodiment of the expander, the screw and check nut assembly 14 is replaced by a pivot pin which ensures the mobility and free hunting of the guiding elements 11. The guiding elements 11 are formed with a plurality of bores 1 5 to ensure a wide range of adjustment for the guide elements 11.For this purpose the bearing 8 is attached vertically adjustably to the supporting element 1 by means of clamping screws 1 6. In a further development of this embpodiment, bores 1 7 are provided at the top of the guide elements 11 for anchoring a spring 1 8 and tensioning element 1 9. If the object is to obtain automatic control in accordance with the pull of a spring, bores 20 for anchoring a further spring 181 and tensioning element 1 91 are provided in the bottom part of the guide elements 11.

The utilisability of the expander according to the first embodiment of the invention is ensured by the feature that the rods 5 are adjusted by the clamping screws 7 in accordance with the required tensile stress of the knitted fabric. The height of the spreading elements 6 can be adjusted by the clamping screw 4 in the mounting plate 3 along the supporting element 1. In the first embodiment, the guide elements 11 are disposed rigidly on the pins 9 and their adjustability is ensured by the clamping screw 10. In the second embodiment of the expander, pivot pins are disposed in the bore 1 5 to ensure the hunting of the guide elements 11. To obtain automatic control in accordance with the pull of a spring, the bores 17, 20 have a spring 18, 18' and tensioning element 19, 19' at the top and/or the bottom of the guide elements 11.

Claims

1. A knitted fabric expander for circular knitting machines, more particularly body fabric circular knitting machines, which comprises a supporting element on which are mounted spreading elements and guide elements for respectively maintaining the fabric in expanded condition and for guiding it to fabric take-off rollers, wherein two spreading elements which are preferably bent in the form of an irregular half hexagon or octagon are adjustably fixed by clamping screws on the supporting element and a mounting plate - and are located parallel with the fabric take-off rollers, and wherein two guide elements adjustable by clamping screws are mounted on the supporting element and in a bearing between the spreading elements.

2. A knitted fabric expander as claimed in claim 1, wherein the top ends of the guide elements are located above or in the plane in which the spreading elements are located.

3. A knitted fabric expander as claimed in claim 1 or 2, wherein the guide elements extend substantially vertically and are formed with bores receiving pivot pins which connect the guide elements to said bearing via pins having a forked end engaging the respective pivot pin.

4. A knitted fabric expander as claimed in claim 3, wherein bores are provided at both the top and bottom ends of the guide elements and have preferably at least one spring.

5. A knitted fabric expander as claimed in any of claims 1 to 4, wherein the guide elements have an elongate plate-like shape of a constant or downwardly tapering thickness.

6. A knitted fabric expander for circular knitting machines, for example body fabric circular knitting machines, substantially as herein described with reference to and as shown in the accompanying drawings.