US3714800A

US3714800A - Shearing device for circular knitting machines

Info

Publication number: US3714800A
Application number: US00847615A
Authority: US
Inventors: A Mazzi
Original assignee: Solis SRL
Current assignee: Solis SRL
Priority date: 1968-08-14
Filing date: 1969-08-05
Publication date: 1973-02-06
Anticipated expiration: 1990-02-06
Also published as: GB1218307A

Abstract

TO PRODUCE A LONGITUDINAL CUT IN KNIT FABRIC DURING THE KNITTING THEREOF ON A CIRCULAR KNITTING MACHINE, A SHEARING DEVICE IN THE FORM OF SCISSORS OR AN ELECTRICAL RESISTANCE IS DISPOSED WITHIN THE NEEDLE CYLINDER OF THE

MACHINE. THE SHEARING DEVICE IS MOVABLE BETWEEN AN OPERATIVE POSITION IN WHICH THE FABRIC IS CUT AND AN INOPERATIVE POSITION.

Description

SHEARINE DEVICE ECR CIRCULAR KNITTING MACHINES A. MAZZI 3 Sheets-Sheet l Feb. 6, 1973 Filed Aug. 5,

E /Nvmrok HRBWS Haul TroRuEyg Feb. 6, 1973 A. MAZZI 3,714,800

SHEARING DEVICE FOR CIRCULAR KNITTING MACHINES Filed Aug. 5. 1969 5 Sheets-Sheet 2 Fi )TOR/VE V5 A. MAzzl 3,714,800

SHEARING DEVICE FOR CIRCULAR KNITTING MACHINES Feb. 6, 1973 3 Sheets-Sheet 3 Filed Aus. s. 1969 .llllil-III uwen-mk Fmaws man.,

3 y INMJ fafa/w BTTORUEYS United States Patent O 3,714,800 SHEARING DEVICE FOR CIRCULAR KNITIING MACHINES Aramis Mazzi, Florence, Italy, assigner to Solis 3.121., Tavarmuzze, Florence, Italy Filed Aug. 5, 1969, Ser. No. 847,615 Claims priority, application Italy, Ang. 14, 1968, 841,972/ 68 Int. Cl. D04h 35/00 U.S. Cl. 66-147 6 Claims ABSTRACT OF THE DISCLOSURE To produce a longitudinal cut in knit fabric during the knitting thereof on a circular knitting machine, a shearing device in the form of scissors or an electrical resistance is disposed within the needle cylinder of the machine. The shearing device is movable between an operative position in which the fabric is cut and an inoperative position.

BACKGROUND OF THE INVENTION This invention relates to a shearing device for circular knitting machines.

SUMMARY OF THE INVENTION According to the present invention there is provided a shearing device for use in a circular knitting machine, said device being capable of producing a longitudinal cut in knit fabric during the knitting thereof on said machine, said device comprising support means secured below the platen for the hooks and having a lateral opening therein facing the needle cylinder at a position at which the cut is to be formed, shearing means mounted on the support means and means operable to move the shearing means through the said lateral opening between an inoperative position within the support means and an operative position at which the cut in the knit fabric is formed.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described, by way of example, with reference to the accompanying drawing, in which:

FIG. 1 is a longitudinal section 0f a shearing device in accordance with the invention mounted on a circular hosiery knitting machine and shown in the operational configuration;

FIG. 2 is similar to FIG. l but shows the device when in-operative;

FIG. 3 illustrates a modification wherein the actual shearing member is an electrical resistance;

FIG. 4 illustrates a detail of a part shown in FIG. 3; and

FIG. 5 is a section on the line V-V of FIG. 4.

Referring now to the drawings and particularly to FIGS. l and 2, a needle cylinder 1, has an upper rim 3 accommodating the sinkers, above which is arranged the hook platen or dial 5, having a series of grooves for radially slidable hooks and intended to knit, among other things, so-called automatic welts. The platen 5 rotates synchronously with the needle cylinder 1. A fixed platform 7 surrounds the needle cylinder below the sinkers.

Within the needle cylinder 1 a shaped shell '9 has from the top downwardly an upper frusto-conical mouth portion 9A, a step 9B, a cylindrical portion 9C and further frustoconical portion 9E and tube 9F. The Iknit fabric M produced is unwound and is turned over, in general, by the action of an airstream in the direction of the arrow f1. The knit fabric M extends from the step 9B towards ICC the tube 9F with a length thereof spaced from the shell 9 corresponding to the

portions

9C, 9E thereof.

:Within the shell 9 a rotary support 10 is secured below the platen 5 and forms a seat, for example comprising a pair of wings or flanges. The support 1i) accommodates a shearing device in accordance with the invention which can be extended through a suitable slot to render it operative on the length of the fabric lying between the step 9B and the tube 9F, in order to effect shearing during the rotation of the unit and the forming of the knit fabric.

According to the embodiment shown in FIGS. 1 and 2, the shearing device takes the form of a pair of scissors, one blade of which extends with a pointed extension to penetrate into the knit fabric. The device includes a blade 14- mounted on a pivot 12 forming an end extension or tip 14A and having an arm 14B biased counterclockwise by a spring 16 around the pivot 12 to an operative position wherein the extension 14A extends into the fabric (see FIG. 1). The operative position is dened by a stop 1S against `which the blade 14 rests. A second, oscillatory, shorter blade 22 is linked to the blade 14 at 20 and overlies (in the side view) the extension 14A. The blade 22 is biased clockwise about the pivot 2.0 by a small spring 24 also acting on the blade 14. The blade 22 is connected by a slot and a pin to a forked head 26, carried by the lower end of a rod 2S, and capable of sliding vertically and rotating together with the

unit

5, 10. The rod 28 is coaxial with the needle cylinder and with the platen S, passes through a wide hole in the arm 14B, and has a head 28A, on which a pair of rollers 30, carried by a non-rotary forked lever 32, can act.

The forked lever 32 is linked at 34 to an arm 36A of a support 3d which is carried by the platform 7. The support 36 forms a guide for a slide member 38 and on this slide member 38 a block 40 is slidable and this acts with its own extension 40A on the lever 32. The slide member 38 is lowered against the action of an opposing spring 41, by means of a liexible control cable 42, controlled for example by a cam of the drum of a program device T, through a tappet P or other cam follower. The block 40 has an extension 40B capable of resting beneath and against the upper rim 3 of the needle cylinder by the action of a spring 44 which biases the block 40 upwardly with respect to the slide member 38, when the slide member 38 has been raised.

Proled cams 46 underlying the rim 3, during the rotation of the cylinder and when the slide member 38 is raised, act on the extension I40B to impose an oscillatory or other reciprocal motion on the block 4i), and through the extension 40A, a corresponding motion on the lever 32 and on the head 28A. Consequently the rod 28 is made to reciprocate and the latter reciprocates the blade 22 in co-operation with the spring 24. This action on the blade 22 only takes place when the slide member 38 is moved upwardly and thus when the rollers 30 of the lever 32 are lowered and the shearingv device is located in the position shown in FIG. 1, that is in the operative position. Movement to this operative position is caused by the spring 16, which tends to move the

blade assembly

14, 14A, 14B in the counterclockwise direction y(as seen in FIGS. 1 and 2) to bring it to rest against the pin 18. Under these conditions, the extension 14A penetrates in the length of the fabric M lying between the portions. 9=B and 9F of the shell, and the fabric slides downwardly along the cutting edge formed by the extension 14A and is sheared |by the oscillation of the blade 22 as the fabric is knitted and while the shearing device is operative. The shearing action begins when the extension 14A is extended and ceases when the extension 14A is retracted into the interior of the flanged support 10, as shown in The configuration of FIG. 2 is achieved when the slide member 38 is lowered by the return action of the cable 42, against the resistance of the spring 41. With this lowering of the slide member 38, the block 40 is also lowered and this block loses contact with the rim 3 and with the profiled cams 46, and therefore ceases to oscillate. The lever 32 is moved to raise the rollers 38 and the latter, in turn, raise the rod 28 and the fork 26 entrains the arm 14B of the blade 1-4 and thereby moves the blade 14 together with the extension 14A against the bias of the spring 16, from the conguration of FIG. l to the configuration of FIG. 2, that is, to the inoperative condition of the shearing device.

Referring now to FIGS. 3 to 5, wherein the same references indicate equivalent members, the flanged support together with a pivot 52 (similar to the pivot 12) links a bell crank lever 54, one arm 54A of which is loaded -by a spring 56 so as to hold the lever 54 against a stop 58 mounted on one ange of the support 10. From this operative configuration the shearing device may be returned into the inoperative configuration by a rotary hollow rod 68 coaxial with the needle cylinder and with the platen 5. A head l68A of the rod 68 carries the arm 54A and serves to move it in a clockwise direction (as shown in FIG. 3) against the action of the spring 56. This raising of the head `68A is effected by the bifurcated end of a lever 72 acting on the rod 68, the lever 72 being pivoted at 74 to a support 76 carried by the fixed platform 7. The motion of the lever 72 is controlled by a flexible cable or other control member `82, operable similarly to the member `42 of the first embodiment.

The rod `68 carries, above a plate j68B on which the bifurcated end of the lever 72 acts, an electrically insulating block 84 which carries a metal track l84A on which a shoe 86 or other contact, borne by the end of the support arm 76 can act. The metal track `841A is connected to a conductor 88, which is secured (see also FIG. 4) to a terminal screw 90, which latter extends into an insulating block 92, housed in the member 54. The terminal screw 90 is electrically connected to an electrical resistance 94 which forms a bridge across the block 92 at the tip-shaped end 54B of the lever 54. The resistance 94 is formed in the upper rear portion of the extension 54B. The circuit is completed through a ground or earth contact formed by the lever S4, the resistance 914, the wire 88, the track 84A and by the shoe 86', when the block 84 is lowered, and then the shoe 86 is in contact with the track 84A, and when the lever 54 is in the operational position, that is, With the extension 54B extending to penetrate through the knit fabric M. When the lever 72 is operated to raise the unit y68, 84, the shoulder or head 68A moves the lever 54 so as to return the extension 54B into the interior of the flanged support 10, and the block 84 is raised so as to be located with the insulating portion in alignment with the shoe 86, thus cutting the electric circuit.

When the device is located in the oper-ational position that is, with the extension 54B projecting, the fabric M (see in particular FIG. 4) tends to slide along the upper edge of the extension 54B, that is in the direction of the arrow i, of the FIG. 4, and thus to surround the resistance 94, which cuts or shears the fabric by fusion. The fabric portions bounding the cut or sheared fabric slide along the extension 54C of the end of the lever 54, so as to be cooled before returning accidentally into contact under the lever 54. The knit fabric portions bounding the cut cannot thus be welded together.

In both embodiments, the knit fabric M, by virtue of the shaping of the shell 9, has a portion of free trajectory where the

extensions

14A and 54B can penetrate at any instant when this is established by the program drum to form along a desired length of fabric being formed, the required longitudinal cut of the fabric, the shearing device rotating With the platen S and synchronously with the needle cylinder.

I claim:

'1. A shearing device for use in a circular knitting machine, said device being capable of producing a longitudinal cut in knit fabric during the knitting thereof on said machine, said device comprising support means secured below the platen for the hooks and having a lateral opening therein facing the needle cylinder at a position at which the cut is to be formed,

shearing means mounted on the support means and means operable to move the shearing means through the said lateral opening between an inoperative position within the support means vand an operative position at which the cut in the knit fabric is formed.

2. A device according to claim 1, wherein said shearing means comprises scissors including a lower blade shaped as a hook to assist penetration of the knit fabric,

an upper blade and means to reciprocate said blades relatively to one another.

3. A device according to claim 2, wherein said scissors further include resilient means biasing the blades to the operative position,

a linkage forming part of said reciprocating means, and acting to stop the blades when the linkage is actuated to retract the blades to the Ainoperative position.

4. A device 'according to claim 1, wherein said shearing means includes an electrical resistance, and

means for cooling the knit fabric after shearing by the resistance.

5. A device according to claim 4, comprising a bell-crank lever reciprocally-mounted within the support means, said resistance being mounted in one arm thereof,

a hollow vertically-extending rod passing through the other arm of the bell-crank lever, and

a lever reciprocal to actuate the rod vertically and thereby entrain the bell-crank lever.

6. A device according to claim 5, comprising an electrical conductor passing through the hollow rod to the resistance.

References Cited UNITED STATES PATENTS 960,755 6/ 1910 Wildman 66-147 1,048,879 12/ 1912 Raven 66-147 2,411,259 11/ 1946 Gilbreath 66--147 2,515,687 7/ 1950 Bausher 66-147 2,543,574 2/ 1951 Gilbreath 66-147 2,749,731 6/ 1956 Moser 66-147 2,933,908 4/ 1960 Thore 66-147 2,995,021 8/ 1961 Payne et al 66-147 2,995,912 8/1961 Payne et al. 66-147 3,218,829 11/ 1965 Seiler 66-147 RONALD FELDBAUM, Primary Examiner