US3800642A

US3800642A - Yarn cutting device

Info

Publication number: US3800642A
Application number: US00237309A
Authority: US
Inventors: W Hasler; L Taylor
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-03-23
Filing date: 1972-03-23
Publication date: 1974-04-02
Anticipated expiration: 1991-04-02
Also published as: CA943407A; DE7210578U; AU4026972A; ZA721895B; DE2213409A1

Abstract

A cutting device for cutting-off tufts of yarn for use with a tufting machine comprising a body having a portion defining a cutter-shaft contacting surface defining at least one yarn entry passage and at least one air passage communicating, a cutter shaft slidably displaceable over said surface and having wall portions defining at least one tuft displacing passage extending therethrough, ducting means aligned with the displacing passage of said shaft to receive tufts therefrom when the shaft is displaced to be in communication with said air passage, and yarn feed means adapted to feed yarn through said yarn entry passage into the tuft displacing passage of the shaft when aligned therewith; said tuft displacing passage and cutter shaft being displaceable from alignment with the yarn entry passage into alignment with said air passage and co-operate with said yarn entry passage and cutter-shaft contacting surface to sever yarn when supplied by said feed means.

Description

United States Patent 1 Hasler ct al.

[4 1 Apr. 2, 1974 YARN CUTTING DEVICE Taylor, 34 Hertford St., Mill Hill, both of Blackburn, England [22] Filed: Mar. 23, 1972 [21] Appl. No.: 237,309

[30] Foreign Application Priority Data Mar. 23, 1971 Great Britain 7626/71 [52] U.S. Cl 83/98, 83/200, 83/277, 83/282, 83/913 [51] Int. Cl D01g 1/04, B65h 51/16 [58] Field of Search 83/98, 99, 199, 200, 580, 83/277, 282, 913

[56] References Cited UNITED STATES PATENTS 1,336,605 4/1920 Becker 83/199 X 3,031,003 4/1962 Clemons 83/199 X FOREIGN PATENTS OR APPLICATIONS 172,595 7/1965 U.S.S.R 83/199 Primary ExaminerFrank T. Yost Attorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak [57] ABSTRACT A cutting device for cutting-off tufts of yarn for use with a tufting machine comprising a body having a portion defining a cutter-shaft contacting surface defining at least one yarn entry passage and at least one air passage communicating, a cutter shaft slidably displaceable over said surface and having wall portions defining at least one tuft displacing passage extending therethrough, ducting means aligned with the displacing passage of said shaft to receive tufts therefrom when the shaft is displaced to be in communication with said air passage, and yarn feed means adapted to feed yarn through said yarn entry passage into the tuft displacing passage of the shaft when aligned therewith; said tuft displacing passage and cutter shaft being displaceable from alignment with the yarn entry passage into alignment with said air passage and co-operate with said yarn entry passage and cutter-shaft contacting surface to sever yarn when supplied by said feed means.

7 Claims, 2 Drawing Figures SHEET 1 (IF 2 PATENTED APR 2 I974 YARN CUTTING DEVICE Prior application: In Great Britain on March 23, 1971 and numbered 7626/71.

The present invention relates to a cutting device for cuttingoff short lengths of yarn from a supply thereof, and is particularly suitable for use with a tufting machine in which the cutting device is required to cut-off such lengths of yarn from one or more yarn supplies and feed them to a hollow needle of the tufting machine.

A tufting machine for manufacturing a tufted carpet in which the cutting device may be used is one in which a plurality of hollow needles extend along a needle bar which is reciprocated so that the needles pass through and are retracted from a backing fabric. A short length or tuft of yarn is passed through the passage formed in each of the hollow needles and is inserted in the backing fabric and may have an adhesive or other means supplied thereto to ensure retention in the backing. Such a tufting machine requires a device for cutting desired lengths of yarn and enabling them to be fed to the needle bar.

According to the present invention there is provided a cutting device for cutting-off short lengths or tufts of yarns from a yarn supply, comprising a body having a portion defining a cutter-shaft contacting surface and having at least one yarn entry passage and at least one air passage communicating with said surface, a cutter shaft slidably displaceable over said surface and having at least one tuft displacing passage extending therethrough, ducting means aligned with the displacing passage of said shaft to receive tufts therefrom when the shaft is displaced to be in communication with said air passage, and yarn feed means for feeding yarn through said yarn entry passage into the tuft displacing passage of the shaft when aligned therewith; the tuft displacing passage and cutter shaft being displaceable from alignment with the yarn entry passage into alignment with the air passage and co-operate with the yarn entry passage and cutter-shaft contacting surface to sever yarn when supplied by the feed means. The body of the cutting device will preferably define a channel portion which will provide the cutter-shaft contacting surface, and the cutter shaft will have a co-operating surface corresponding therewith.

Preferably the cutter shaft will be in the formof a cylindrical bar and the channel be of corresponding partcircular section. In this preferred arrangement, the cutter shaft may be displaceable to execute circular rotation or oscillatory movement which may be axial or rotary and in which latter case, the amplitude will preferably be substantially 22% or 90.

Preferably a plurality of yarn entry passages will be provided in the body and supplied by a plurality of yarn feed means. A corresponding plurality of air passages and tuft displacing passages will be provided and the passages in each group may be arranged in straight line formation or relatively offset about a line to reduce the overall dimensions of the device. A plurality of tuft ducting means will also be provided and, in use, each be communicatable with a needle of a tufting machine.

The body may be a composite one made up of a number of connected sections. When the cutter shaft is in the form of a cylindrical bar, it may be provided on the side away from the yarn entry passage with spring loaded or other clamping means which urge the operative portion of the shaft against the operative contacting surface of the body thus ensuring that the cutter shaft surface and the contacting surface of the body are in close contact and there fore capable of making a clean and sharp cut through the yarn. The ducting means may comprise a flexible tube, preferably of plastics material, connected to the outlet orifice of each tuft displacing passage in the cutter shaft when such is arranged to execute oscillatory movement or may comprise an aperture extending through a body section of the device. In either event, the ducting means, in use, communicates with or is located in the main tuft feed line of a tufting machine. Each needle of such a machine maybe associated with a plurality of cutters.

The cutting device will include a yarn feed means which operated to displace predeterminable lengths of yarn through the yarn entry passage into the displacing passage of the cutter shaft. The yarn feed means may comprise a member having a channel along which yarnmay pass, an intermittently driven wheel having a portion extending into or adjacent a first opening communicating with the channel and a displaceable pressure means, for example, a roller or skid, substantially op- .posite said wheel portion and displaceable through a second opening communicating with the channel to urge yarn against said wheel to feed the yarn through the channel means and yarn entry passage communicating therewith into the passage in the cutter shaft. The pressure means may be carried by a piston rod and piston and cylinder arrangement and be spring biassed away from the yarn. The piston may be pneumatically displaceable by compressed air which may be controlled by a solenoid valve. Auxiliary yarn feed means may be provided and comprise an air duct communicating with the yarn entry passage and in the junction region therebetween, a venturi formation will be provided to encourage yarn to move into the cutter shaft passage. Where a plurality of feed means are required, a plurality of flat plate-like sections may be provided, each having the channel and openings formed on one surface and being built up in side by side juxtaposition to form a unit. A single wheel may be provided, possibly having a rubber or other coating, and have a plurality of circular flanges or projections which separate the sections.

Alternatively, the cutting device may include yarn feed means which may each comprise a reciprocable yam-pushing member through which yarn may pass and having a portion thereof extending within the yarn entry passage, a yarn clamp operable to clamp the yarn after leaving the pushing member, and a non-return device adapted to act on yarn within the pushing member to ensure yarn passes only towards the cutter shaft. The yarn clamp is arranged to act upon the yarn only during movement of the pushing member away from the cutter shaft and only when supply of a tuft is required to be produced by the cutting device during the subsequent movement of the pushing member and non-return device towards the cutter shaft.

The cutting device will normally be incorporated in a tufting machine substantially as hereinbefore described and arranged to operate in synchronism with the operational movements of the needle bar and other components of the machine such that a tuft of predetermined length will be provided when desired. One or more cutting devices may be advantageously provided and supplied with differently coloured yarns. Particular feed means thereof supply a required colour and are operated to supply tufts of said required colour to the needles of the machine under control of a colour pattern. In addition to, or alternatively to, tufts of different lengths may be required to form a carpet with sculptured pattern and this may be effected by controlling operation of the cutting devices with a suitable pattern. The tuft lengths may be varied by adjustably controlling the throw of the feed means of a cutting device or by actuating cutting devices with different settings of the feed means. Each needle of the machine may be associated with a plurality of ducting passages of one or more cutting devices although such are driven so that the needle receives only one tuft per operational stroke.

A linkage between the feed means and cutter shaft will normally be provided and have a lost motion action such that the cutter shaft is stationary during part of the revolution or oscillation of the cutter shaft with its diametral passage lined up with the yarn entry passage in the body. During this time, if required, a predetermined length of yarn is fed by the yarn feed means into the passage in the cutter shaft. In the preferred embodiment the linkage subsequently rotates the cutter shaft through substantially 22 or 90, cutting off the yarn fed into it from the yarn still left in the body. At the end of the travel, the cutter shaft ceases to rotate and its passage lines up at both ends with the air passage connected to a pressurized air supply and with the yarn ducting passage communicating with the associated needle. When the cutter shaft reaches this position, pressurized air blows the tuft of yarn from the passage in the cutter shaft to the needle. Thereafter the cutter shaft rotates on 90 or backwards 22 so that its diametral passage lines up once more with the passage in the body, ready for the introduction and cutting-off of a further tuft of yarn.

With a plurality of cutting devices, all the cutter shafts rotate through their predetermined angles at the same time, so that at any one time, any tuft of yarn fed forward by the feed means operated by the pattern is cut off by a particular cutter shaft, there being only one tuft cut-off at any particular time for one needle. Since all the cutter shaft diametral passages line up with the air passages and the ducting passages at the same instant, whichever cutter has cut-off a tuft aligns its diametral passage containing this tuft with the air supply, which then proceeds to drive the tuft out of the shaft and through all the ducting passages and pipes in series into the associated needle.

Since a plurality of needles are required in order to manufacture a carpet, a plurality of cutting device body assemblies will be provided in a tufting machine extending parallel to or at any angle up to 90 to the needle bar, each body being supplied with yarn. The feed means associated with the said bodies may all be driven by a common drive and the associated cutter shafts may be operated from this power drive either by means of a linkage, suitably shaped cams or other similar means.

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

FIG. 1 illustrates a cutting device with yarn feed means and cutter shaft; and

FIG. 2 illustrates an alternative embodiment of a cutting device.

The cutting device illustrated in FIG. 1, comprises a composite body 11 made up of interconnected sections and having a portion 1 1 defining a curved cutter shaft contacting surface of radius substantially corresponding to that of the shaft. A plurality of radially bored yarn entry passages 12 and radially bored air passages 13 are provided in line in the body although only one of each is shown.

A cutter shaft 14 in the form of a cylindrical bar has a plurality of tuft displacing ducts 15 diametrically bored therethrough (only one duct being shown in the sectional view). It is to be understood that whilst the following description refers to component features in the singular, a plurality of such component features are provided in line formation in the body and cutter shaft and other common components.

Ducting means 16 is provided in a body section 11 and, in use, is connected via branch pipes (not shown) with the main feed duct (not shown) of a needle of a tufting machine.

Yarn 17 from a creel (not shown) is fed to the cutter shaft 14 by feed means which include a clamp comprising an upwardly spring biassed piston and rod 18 downwardly displaceable in body section 11" by means of compressed air entering through duct 19 from a source (not shown) so as to clamp the yarn 17 in passage 12 with the end 18 of piston rod 18.

The yarn feed means also includes a yarn tube 20 securely mounted in a reciprocating bar 21 (which in fact carries a plurality of tubes, only one of which is shown). One end of tube 20 extends, slidably into the yarn entry passage 12. The other end of tube 20 carries a nonreturn device in the form of a pawl 22 pivotally mounted on plate 22' secured to the tube 20. The pawl 22 is downwardly biassed to prevent yarn from moving away from the cutter shaft and to permit movement towards said shaft. The biassing means comprises a compression spring 23 located around tube 20 and acting between bar 21 and against a flanged sliding sleeve 24 in turn acting on front face of pawl 22.

In operation, yarn 17 extends from a creel (not shown) under pawl 22, through tube 20 and into passage 12 under clamping piston rod 18'. Yarn is caused to reciprocate under clamp rod 18' under the action of the reciprocating bar 21 which is driven by a suitable cam or other means, e.g., Geneva motion (not shown), acting on the bar or an end section thereof. Yarn is fed into cutter shaft passage 15 when compressed air is caused, by suitable control means, to be fed into passage 19 to actuate clamping piston 18 so that yarn is clamped in passage 12 during movement of bar 21 and tube 20 away from the cutter shaft. The action of the non-return pawl 22 causes the tube to take-in fresh yarn and to push yarn into aligned passage 15 during its next forward movement; the clamping piston-rod 18 being previously lifted off the yarn. The cutter shaft 14 subsequently rotates through 22 and in so doing the adjacent edges of

passages

12 and 15 act to cut the yarn. Passage 15 is then brought into alignment with air passage 13 whereupon, under the action of a slide valve, compressed air blows the tuft 25 out of passage 15, through ducting passage 16 to a feed line of a needle of a tufting machine (not shown). The cutter shaft 14 then rotates backwardly through 22% into alignment with passage 12 to permit feed of a fresh tuft length and the movement is subsequently repeated. Suitable dwell periods in the motion of the cutter shaft will be provided by the drive therefore to permit entry of yarn and exit of tufts to and from the passage 15.

The bar 21 and tube 20 are constantly oscillated in appropriate phase with the cutter shaft 14, and when no yarn is supplied to the cutter shaft, the tube and its yarn contained therein both oscillate continuously. At the most forward position of the tube 20, Le, the one where it approaches the cutter, the free end of the oscillating yarn just reaches the cutting faces between the rotary cutter shaft 14 and the stationary body portion but does not enter the cutter shaft.

The cutter shafts and tubes oscillate together, the operation of one clamp causing a tuft to be fed to a particular needle at any particular time. Since, in a tufting machine, a plurality of needles is required in order to produce a tufted carpet, a plurality of devices are also required in a tufting machine. The yarn tubes and cutter shafts are oscillated in synchronism by means of for example, eccentrics, cams, levers or chain mechanisms (not shown).

The body portions 1 1 contacting shaft 14 have liners of carbon-metal or other self lubricating metal and the cutting edges of at least passages 12 and may have hardened or silver steel bushes (not shown) set thereinto to maintain sharp cutting edges.

The cutting device shown in FIG. 2 differs in that the interconnected body sections 11 which receive cutter shaft 14 have air passages 13 and ducting means 16 which are arranged to be incorporated in the main feed line of a needle in a tufting machine. The cutter shaft 14 oscillates through 90 and operates in a manner similar to the previous embodiment. The lining metal and bushes previously described are not shown. Similar parts of this embodiment have the same reference numerals applied thereto.

The non-return device of this embodiment differs substantially from the previous one and comprise a tube bar 27 having a recess in which a pawl 28 is pivotally mounted, extends through an aperture in the tube and is biassed into engagement with yarn 17 by means of compression spring 29. The bar 27 is mounted on slides illustrated at 30 and is oscillated in phase with cutter shaft by suitable drive means and operates in similar fashion to the previous embodiment.

In this embodiment, ducting means 16 are provided, unlike in the previous system, which do not individually lead to the main feed line of a tufting machine, but rather are directly located in the main feed line and the cutting devices may be arranged vertically, one above the other.

We claim:

1. A cutting device for cutting-off tufts of yarn from a yarn supply comprising:

a. a body having a portion defining a cutter shaft contacting surface, said body having at least one yarn entry passage and at least one air passage therethrough each communicating with said cutter shaft contacting surface,

b. a cutter shaft slidably displaceable with respect to said cutter shaft contacting surface and having at least one tuft displacing passage extending therethrough, said tuft displacing passage being displaceable from alignment with said yarn entry passage to alignment with said air passage, the relative motion of the peripheral edges of the ends of said tuft displacing passage and said yarn entry passage acting to sever the yarn extending therethrough, c. ducting means disposed with respect to said tuft qisfiasimnasasstq c ve tufts therefrom when b. said cutter shaft is a cylindrical bar having said yarn displacing passage extending diametrically therethrough.

3. A cutting device according to claim 1 wherein said yarn feed means includes:

a. a bar reciprocally displaceable with respect to said cutter shaft, said bar securedly connected to at least one hollow tubular member extending into said yarn entry passage,

b. means to prevent displacement of yarn within each of said hollow tubular members away from said cutter shaft, and

c. clamping means to prevent displacement of yarn during movement of said hollow tubular member away from said cutter shaft while permitting displacement of yarn during movement of said hollow tubular member toward said cutter shaft.

4. A cutting device according to claim 3 wherein said clamping means includes a piston and rod attached thereto, said piston and rod being reciprocally moveable within a cylinder in said body, said rod extending into said yarn entry passage and engaging the yarn therein to prevent movement of said yarn when said piston is acted on by fluid means, said rod being normally biased away from engagement with said yarn.

5. A cutting device according to claim 3 wherein said means to prevent displacement of yarn away from said cutter shaft includes a pawl extending into said hollow tubular member, one end of said pawl being biased into engagement with the yarn in said hollow tubular mem her to prevent movement of said yarn away from said cutter shaft.

6. A cutting device according to claim 5, wherein said means to prevent displacement of yarn away from said cutter shaft is mounted in the reciprocable bar carrying said tubular member.

7. A cutting device according to claim 5, in which said tubular member extends on two sides of the reciprocable bar and said means to prevent displacement of yarn away from said cutter shaft is attached to the end of the tubular member remote from said cutter shaft. l

Claims

1. A cutting device for cutting-off tufts of yarn from a yarn supply comprising: a. a body having a portion defining a cutter shaft contacting surface, said body having at least one yarn entry passage and at least one air passage therethrough each communicating with said cutter shaft contacting surface, b. a cutter shaft slidably displaceable with respect to said cutter shaft contacting surface and having at least one tuft displacing passage extending therethrough, said tuft displacing passage being displaceable from alignment with said yarn entry passage to alignment with said air passage, the relative motion of the peripheral edges of the ends of said tuft displacing passage and said yarn entry passage acting to sever the yarn extending therethrough, c. ducting means disposed with respect to said tuft displacing passage to receive tufs therefrom when said tuft displacing passage is in communication with said air passage, and d. yarn feed means adapted to feed yarn through said yarn entry passage into said tuft displacing passage when said passages are in alignment.

2. A cutting device according to claim 1 wherein: a. said cutter shaft contacting surface is concave and cylindrical, and said yarn entry passage, air passage, and ducting means extend radially from said surface through said body, and b. said cutter shaft is a cylindrical bar having said yarn displacing passage extending diametrically therethrough.

3. A cutting device according to claim 1 wherein said yarn feed means includes: a. a bar reciprocally displaceable with respect to said cutter shaft, said bar securedly connected to at least one hollow tubular member extending into said yarn entry passage, b. means to prevent displacement of yarn within each of said hollow tubular members away from said cutter shaft, and c. clamping means to prevent displacement of yarn during movemEnt of said hollow tubular member away from said cutter shaft while permitting displacement of yarn during movement of said hollow tubular member toward said cutter shaft.

5. A cutting device according to claim 3 wherein said means to prevent displacement of yarn away from said cutter shaft includes a pawl extending into said hollow tubular member, one end of said pawl being biased into engagement with the yarn in said hollow tubular member to prevent movement of said yarn away from said cutter shaft.

7. A cutting device according to claim 5, in which said tubular member extends on two sides of the reciprocable bar and said means to prevent displacement of yarn away from said cutter shaft is attached to the end of the tubular member remote from said cutter shaft.