US3135298A

US3135298A - Electric thread cutter

Info

Publication number: US3135298A
Application number: US163463A
Authority: US
Inventors: George M Marks
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-01-02
Filing date: 1962-01-02
Publication date: 1964-06-02
Anticipated expiration: 1981-06-02

Description

J1me 1964 e. M. MARKS ELECTRIC THREAD CUTTER Filed Jan. 2, 1962 FIG. 5

INVENTOR. GEORGE M. MARKS FIG.6

United, States Patent 31,135,298 7 ELECTRIC THREAD CUTT"R George M. Marks, Rte. 6, Greenville, S.C. Filed Jan. 2, 1962, Ser. No. 163,463 4 Claims' (Cl. 139-463) justment and sharpening, but are not reliable for severing synthetic thread composed of twisted fibers such as nylon, Celanese, Dacron, Orlon and like tough thermoplastic materials. Not only are such threads difficult to shear cleanly, but when cut, the fibers untwist and ravel because of plastic memory.

When cloth is woven in well known power looms, the starting and finish lengths of the weft thread of each bobbin carried by the shuttle projects from the edge of the fabric and is held linear by clamping means. These threads cannot be cut close to the edge of the cloth by ordinary shear methods since the raveling would run into the cloth, and, thus, render a portion thereof defective. This results in the necessity for shearing the thread with a predetermined length projecting from the cloth which is laterremoved by hand methods.

The present invention to be hereinafter described is one embodiment of the invention adapted to power power loom 2 by screw 3 which also retains terminal 4 of a high tension conductor 5. The upper end of a fiat spring 6 is also retained under block 1 in contact with the machine by screw 3. The lower free portion of spring 6 retains a dielectric body 7, preferably made from porcelain or other high dielectric material, and isrretained in fixed relation thereon by screw 8, as shown.

'An integral V-shaped guide 9 is formed in one side of body 7 and is shaped for frictional engagement with the edge surface of the cloth in the loom.

A lower'electrode 10 is secured tobody 7 by screw 11 in contact with the upturned lower end of spring 6, as shown. An'upper electrode 12 is secured to body 7 by screw 13 and is positioned, as shown, providing a fixed elongated spark gap 14 with parallel knife-like edges. In the interest of long life, the electrodes are best made of metal alloy high in nickel or tungsten or from metals in the platinum group.

A flexible conductor 15 has a terminal 16 on its lower end also retained by screw 13. A second terminal 16 on conductor 15 wide terminal 17 are retained to block 1 by screw 18. A second high tension conductor 19 terminates in terminal 17.

FIG. 2 is a fragmentary front view of the spark'gap assembly applied to a typical power loom with a fabric 2t? in the process of being woven with a pair of weft looms and overcomes the above objections and disadvantages by the provision of an automatic means for severing threads in close proximity with the edge of woven synthetic cloth and having an. additional advantage of welding together the severed fibrous ends of the filaments of the thread into a revel-proof nodule and is a principal object of the invention.

A further object ofrthe invention is the'provision of a spark gap means for intercepting and severing threads by heat from a high voltage spark discharge.

Another object of the invention is the provision of a spark gap including an electric transformation means for generating a continuous spark in said gap including switch and circuit means responsive to the movement of a thread for severing same by the heat of said spark when the thread is moved into the gap.

A further object of the invention is the provision of a spark gap movably positioned to intercept laterally moving weft threads projecting from the cloth in a power loom and severing same in close proximity to the edge of said cloth by means of a high tension spark generated across said gap.

These and other objects and advantages of the invention are described and shown in the following specification and drawing in which:

FIG. 1 is a perspective view of a thread severing spark gap assembly for a textile machine.

FIG. 2 is a front elevation of the spark gap assembly, shown FIG. 1, applied to a power loom. I

FIG.- 3 is a side elevation of the device, shown FIG. 2.

FIG. 4 is a greatly enlarged illustration of a section of multiple filament thread.

FIG. 5 illustrates the thread, shown FIG. 4, after heat severance.

FIG.'6 is a schematic diagram of electric components and circuit for energizing the spark gap, shown FIG. 1. Referring to FIGS. 1 and .2, a dielectric block 1 is ecured to a fixed grounded conductive portion of a threads 21 representing the end and start portion of the thread in a pair of bobbins. These threads are retained in a linear position by a typical weft thread clamp means illustrated by clamp elements 22-22 in they loom 2.

A sensitive self-restoring normally open switch 23 is secured to the machine with the'act'uatorarm 24 thereof positioned to be engaged'and moved by the forward movement of the threads 21, better shown inFIG; 3.

It is now apparent that when the cloth 20 as woven is moved in the direction shown by arrow, FIG. 3, the actuator 24 will be encountered by the threads 21, held and moved by the clamp 22, and operate the switch into closed position just prior to the thread entry into the spark gap 14 between

electrodes

10 and 12.

FIG. 6 illustrates a circuit including atypical A.C. step-up ignition transformer 25 having the primary 26 thereof connected to a source of conventional A.C. electric energy L -L with switch 23 in series therewith. The high potential secondary 27 of the transformer is connected by

conductors

19 and 5 to

electrode terminals

18 and 3 corresponding to

elements

15 and 16 and

electrodes

12 and 10 respectively, as shown, with the conductor 5 grounded to the loom 2 as a safety measure.

In operation and under the assumption that the woven cloth in the machine is moving in the direction shown by arrow in FIG. 3, each pair of weft threads 21 will engage actuator 24 of switch 23 and move same into closed position and, thus, produce a continuous spark across the gap 14. Concurrently, the threads 21 will enter the gap 14 and be intersected by the spark therein resulting in the severance of the thread by melting and the welding together of the filaments in the ends of the thread. Simultaneous with theseverance of the thread,- the actuator arm 24 will permit the switch to return to its normal open position and de-energize the spark gap.

FIG. 4 illustrates a portion of multi-filament thread 31 greatly enlarged and FIG. 5 illustrates the welded bonded nodule ends 32 following severance by the electric spark in the gap 14. g

It is to be noted that since the spark will always follow the shortest path between the electrodes, the elongated electrodes are provided for long life since the spark may travel the entire length of the electrodes as portions of the edges thereof deteriorate. Furthermore, the

narrow elongated gap provides for containing the spark 3 in a linear path for severing weft threads close to the edge of the cloth.

It is also to be noted that alternate electric means may be used for generating the high potential required in the spark gap such as the use of radio frequency or direct current high potential generators.

It has been found that the above described device may also be used for severing small metal filaments as well as combustible threads such as cotton, wool and silk by incorporating certain modifications in construction.

It is understood that certain modifications in the above described construction, utilizing the features described, are intended to come within the scope of the appended claims.

Having described my invention, I claim:

1. In a textile machine, apparatus for severing threads projecting from the edge of a cloth comprising a pair ofelectrodes secured in predetermined fixed spaced relation by dielectric means forming a spark gap, a source of electric energy of predetermined potential connected to said electrodes adapted to produce a continuous spark across said gap, a holding means adapted to retain threads in a substantially linear position for lateral entrance into said gap, said holding means providing relative motion between said spark gap and said threads for entering the latter into said gap spaced between said electrodes whereby the heat of said spark severs said threads when said threads move relative thereto, and guide means disposed substantially perpendicular to the plane of said cloth, said guide means carrying said electrodes and adapted to engage the edge of said cloth from which said threads extend after'said threads are severed by the heat of said spark, said guide means movable with uniform distance from said edge.

2. Apparatus in accordance with claim 1 wherein said threads are synthetic threads. 3. Apparatus in accordance with claim '1 wherein there respect to the edge of said cloth to maintain said gap at o is provided an electric transformer interconnecting said electrodes and said sources of electric energy to produce a continuous spark across said gap when energized and electric switch means between said source of electric energy and said electrodes, said electric switch means being actuated by the movement of said threads in engagement therewith.

4. In a power loom, a device of the character described for severing filaments from the edge of moving material, a fixed spark gap comprising a pair of electrodes secured to an insulating body, said electrodes terminating in a pair of oppositely positioned parallel spaced blades of predetermined length forming said gap, said body including a guide, yieldable means supporting said body adjacent the said edge of said material and disposed substantially perpendicular to the plane of said material with said guide in responsive slidable engagement with the said edge of said material, electric means connected to said electrodes producing a continuous spark in said gap when energized whereby a filament projecting from the said edge of said material moving into said gap is severed by said spark in predetermined proximity to the said edge of said material.

References Cited in the file of this patent

Claims

1. IN A TEXTILE MACHINE, APPARATUS FOR SEVERING THREADS PROJECTING FROM THE EDGE OF A CLOTH COMPRISING A PAIR OF ELECTRODES SECURED IN PREDETERMINED FIXED SPACED RELATION BY DIELECTRIC MEANS FORMING A SPARK GAP, A SOURCE OF ELECTRIC ENERGY OF PREDETERMINED POTENTIAL CONNECTED TO SAID ELECTRODES ADAPTED TO PRODUCE A CONTINUOUS SPARK ACROSS SAID GAP, A HOLDING MEANS ADAPTED TO RETAIN THREADS IN A SUBSTANTIALLY LINEAR POSITION FOR LATERAL ENTRANCE INTO SAID GAP, SAID HOLDING MEANS PROVIDING RELATIVE MOTION BETWEEN SAID SPARK GAP AND SAID THREADS FOR ENTERING THE LATTER INTO SAID GAP SPACED BETWEEN SAID ELECTRODES