US3460212A - Fringe trimming method - Google Patents

Description

1969 N. E. ELSAS ETAL 3,460,212

FRINGE TRIMMING METHOD Filed May 25. 1967 'INVENTOR) MAW/xv L. 2545 77/04/45 M flWl/MI United States Patent 3,460,212 FRINGE TRIMMENG METHOD Norman E. Elsas, Atlanta, and Thomas M. Bryan 1!, Jefferson, 6a., assignors of fifty percent each to Nemo Industries, Inc, Atlanta, Ga, and The Jefferson Mills, Incorporated, Jefierson, Ga., both corporations of Georgia Filed May 25, 1%7, Ser. No. 641,352 Int. Cl. 1306c 13/00 US. Cl. 26-18%! 4 Claims ABSTRACT OF THE DISCLOSURE Fringe trimming method for trimming the loose threads from the edge of fabric, wherein the fabric is moved along a predetermined path, the loose threads of the fringe are urged away from the fabric in a plane parallel to the fabric so as to unsnarl the individual threads from one another, the loose threads are urged in a direction normal to the plane of the fabric, the edge of the fabric determined, and the threads are urged away from and parallel to the surface of the fabric, whereupon cutting means sever the fringe from the fabric.

Background of the invention When weaving fabrics, some fabrics are woven with a fringe of loose threads along one edge thereof. This fringe is inherently uneven because of the weaving process, and it is desirable that the fringe be trimmed from the fabric before the fabric is processed through finishing operations since the fringe can interfere with the guiding and holding of the fabric during the finishing operations.

Usually the edge of the woven fabric in which fringes of loose threads are present curves so that the edge of the fabric is not perfectly straight. When the fringe is being cut from the fabric the cutting device should be constantly repositioned with respect to the fabric to properly trim the fringe threads away from the fabric. When trimming the fringe of the fabric by mechanical means as the fabric is processed through the various other finishing steps, it is difiicult to ascertain the exact edge of the fabric through the mass of loose threads present in the fringe since these threads tend to tangle among themselves to form lumps which might be mistaken by mechanical sensing means as the edge of the fabric.

Summary of the invention This invention comprises a fabric fringe trimming method and apparatus including the steps of urging the fringe threads away from the fabric in substantially the same plane occupied by the fabric so as to untangle and straighten the fringe threads, urging the threads in a plane normal to the plane occupied by the fabric to expose the edge of the fabric at the base of the fringe threads, sensing the edge of the fabric at the base of the fringe threads while the fringe threads extend in a plane normal to the plane occupied by the fabric, urging the fringe threads away from the fabric in the direction generally coextensive with the plane occupied by the fabric, and trimming or cutting the fringe threads away from the fabric. Streams of air are directed toward the fringe threads to orient the threads as desired, and photoelectric sensing elements or feeling members are utilized to determine the edge of the fabric at the base of the fringe threads.

Accordingly, it is an object of this invention to provide a method of trimming a fringe of loose threads from an edge of woven fabric, wherein the edge is accurately trimmed in spite of the unevenness of the edge of the fabric.

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Another object of this invention is to provide a method of economically trimming a fringe of loose threads from an edge of fabric at substantially any distance desired from the edge of the fabric.

Another object of this invention is to provide apparatus for economically and expediently trimming the loose fringe threads from a woven fabric, which is adapted to be combined with apparatus for manufacturing or otherwise processing the fabric.

Another object of this invention is to provide apparatus for trimming the loose fringe threads from fabric which functions to cut the threads at a predetermined distance from the edge of the fabric in spite of the crookedness of the edge.

Another object of this invention is to provide apparatus for trimming the loose fringe threads from a woven fabric, which accurately determines the edge of the fabric adja cent the fringe, cuts the fringe threads at a predetermined distance from the edge of the fabric, and compensates for any curves or crookedness in the edge of the fabric.

Other objects, features and advantages of the present invention will become apparent upon reading the following specification when taken in conjunction with the accompanying drawing.

Brief description of the drawing FIG. 1 is a schematic perspective view of the fringe trimming apparatus.

FIG. 2 is a partial perspective view of the fringe trimming apparatus.

FIG. 3 is a schematic view of the control mechanism utilized to move the movable frame of the fringe trimming apparatus.

FIG. 4 is a bottom perspective view of the fabric as it passes beneath the photoelectric cell.

FIG. 5 is a bottom perspective view, similar to FIG. 4, but showing an edge feeler.

FIG. 6 is a side elevational view of the contact roll utilized to drive the anvil of the cutting mechanism.

Description of the embodiments Referring now more particularly to the drawing, in which like numerals indicate like parts throughout the several views, FIG. 1 shows, schematically, the fabric as it is processed through fringe trimmer 9. The fabric 10 is moved in the direction indicated by arrow 11 over rollers 12 and 13 which are part of the fabric manufacturing or processing apparatus. A plurality of air ducts are placed at spaced intervals along the path of fabric 19 as it passes from roller 12 to roller 13. Air ducts 15 and 16 are positioned above and below the fabric 10, respectively, and the exhaust ends 17 and 18 of air ducts 15 and 16 are oriented toward the edge 19 of the fabric 10 which carries fringe 20 so that the air flowing through these ducts and out of the exhaust ends 17 and 18 functions to blow the fringe threads 20 away from fabric 10, so that the fringe threads stand laterally away from the fabric.

Air duct 21 is positioned above the path of travel of fabric 10 and its lower exhaust end 22 is positioned above the fringe 20 of the fabric. Air duct 21 and its exhaust end 22 function to duct air in a downward direction, generally perpendicular to the plane of the fabric 10, so as to urge the fringe threads 20 in a downward direction. A light source 23 is positioned below the plane of the fabric 18, below edge 19, and a pair of photoelectric cells 24 are positioned above the plane of fabric 10, above light source 23. Light source 23 and photoelectric cells 24 are positioned closely adjacent air duct 21, where the fringe threads of fabric 10 extend in a downward direction from the influence of the air passing through air duct 21.

Air ducts 25 and 26 extend toward fabric 10, from above and below the plane of the fabric, respectively, and their exhaust ends 27 and 28 are constructed in a manner similar to the exhaust ends 17 and 18 of air ducts and 16, so that the air passing through ducts and 26 urges the fringe threads to extend laterally from fabric 10, in the same plane occupied by the fabric 10. An anvil 29 is positioned below fabric 10, and constructed to rotate in the direction as indicated by arrow 30. The surface of anvil 29 is in tangential contact with the lower surface of fabric 10 and moved at a speed slightly faster than the fabric 10. A cutting disc 31 is positioned above fabric 10 and biased toward anvil 29. Cutting disc 31 and anvil 29 are adjustable so that cutting disc 31 is automatically positioned at the edge 19 of fabric 10 and the fringe threads 20 will be cut or crushed from the edge of the fabric. Vacuum conduit 32 is positioned below the plane of fabric 10, adjacent anvil 29. Vacuum conduit 32 is connected to a source of vacuum (not shown) and any fringe threads removed by cutting disc 31 will be removed from the vicinity of fringe trimmer 9" by vacuum conduit 32.

As is best shown in FIG. 2, fringe trimming apparatus 9 is mounted on a stationary base or platform 34 which can be connected to other components of the assembly line or supported from the surface of the floor. A pair of slot- ted support members 35 and 36 are rigidly connected to the upper surface of platform 34, in inward facing relationship, and movable platform 38 is slidably received therein. Rotatable anvil 2.9 is supported on movable platform 38 by hearing blocks 39 and 40. L-shaped support frame 41 is supported by, and movable with, movable platform 38 by means of stanchion 42. Support frame 41 includes a base member 44 extending parallel to the axis of rotation of anvil 29, over the plane of fabric 10, and leg 45 which extends parallel to the direction of the path of travel of the fabric 10. A pair of stationary tensioning bars 46 and 47 are supported in a horizontal plane by leg 45 at its end remote from base member 44. Tensioning bars 46 and 47 extend perpendicular to the path of travel of fabric 10, and the fabric is arranged to pass beneath tensioning bar 46 and over tensioning bar 47.

Driving mechanism 49 is supported by leg 45 of support frame 41. Driving mechanism 49 includes a shaft 50 rotatably mounted in bearing block 51 which is connected to leg 45. Contact roll 52 is rigidly connected to shaft 50 by discs 54 and 55. Contact roll 52 is elastic and positioned above tensioning bar 47 and engages fabric 10 as it passes over tensioning bar 47. The diameter of contact roll 52 can be varied by adjustinng disc 55 closer to or further away from disc 54 by means of nuts :6. Flexible drive shaft 58 is connected at one of its ends to rotatable drive shaft 50, and at the other of its ends to anvil 29. Thus, rotation of contact roll 52 in the direction as indicated by arrow 59 by frictional engagement with the moving fabric 10 causes anvil 29 to rotate in the direction as indicated by arrow 30.

Manifold 60 is mounted on leg 45 of support frame 41, and a source of compressed air (not shown) communicates with inlet duct 61. Air ducts 15, 16, 21, 25 and 25 communicate with manifold 60 and duct air toward fringe 20 of fabric 10, as previously explained. Air duct 62 communicates at one of its ends with manifold 60, and at the other of its ends with pressure control valve 64. Pressure control valve 64 is of conventional design and includes gauge 65 and control knob 66. Air duct 68 communicates at one of its ends with the outlet 69 of control valve 64, and at the other of its ends with fluid cylinder 70. Cutter disc housing 71 is supported by base member 44 of support frame 41, and fluid cylinder is mounted above housing 71. Fluid cylinder 70 includes a piston (not shown) which is urged in a downward direction by the air pressure admitted to fluid cylinder 70 through air duct 63, and the piston is connected to the axle (not shown) of cutter disc 31. Thus, the air pressure communicating with fluid cylinder 70 urges cutter disc 31 toward anvil 29. Control valve 64 controls the pressure of air admitted to fluid cylinder 70, and thus the force with which cutter disc 31 is urged toward anvil 29.

Light source 23 is mounted on movable platform 38, and the pair of photoelectric cells 24 is suspended above light source 23 by means of support bracket 72. Support bracket 72 is adjustable and comprises support arm 74 rigidly attached to leg 45 of support frame 41, and adjustable arm 75. Adjustable arm 75 can be moved toward or away from leg 45 by means of slots 76 sliding over bolts 78. Also, the pair of photoelectric cells 24 is rotatably mounted in adjustable arm 75, so that the effective distance between the pair of photoelectric cells with respect to the edge 19 of fabric 10 can be varied.

The pair of photoelectric cells 24 is electrically connected to junction box 79 by means of electric conductors 80. Junction box 79 is connected by electrical conductors 81 and 82 from opposite ones of the pair of photoelectric cells 24 to solenoid control valves 83 and 84. Air duct 85 is connected at one of its ends to manifold 60, and at the other of its ends to solenoid control valve 83, while air duct 86 is connected at one of its ends to manifold 60 and at the other of its ends to solenoid control valve 34. Fluid cylinder 88 is rigidly connected to stationary platform 34 by means of brackets 89. A piston 90 (FIG. 3) is slidably received in cylinder 88 and includes shafts 91 and 92 extending through opposite ends of cylinder 88. Shaft 91 is connected at its outer end to linkage 94. Linkage 94 includes pivotal link 95 connected to shaft 91 at one of its ends and pivotally connected to station ary platform 34 at the other of its ends by means of pivot pin 96. Connecting link 98 is connected at one of its ends to pivotal link 95 at a point intermediate the ends of pivotal link 95, and at its other end to movable platform 38, by means of pivot pins 99 and 100.

Fluid cylinder 88 communicates at each of its ends by means of air ducts 101 and 102 with solenoid control valves 83 and 84. Solenoid control valves 83 and 84 each include control spool 104 with valve spools 105 and 106 maintained in spaced relationship by connector 107. Bleeder valves 109 are connected to solenoid control valves 83 and 84. Control spools 104 are normally maintained in their down position, as shown in FIG. 3, so that air ducts S5 and 86 normally communicate with air ducts 101 and 102. When the coil of the solenoid is energized control spools 104 will be moved against the bias of their springs 110 to an upward position where air ducts 85 and 86 will be blocked by valve spools 105 and air ducts 101 and 102 will be in communication with bleeder valves 109.

As is best shown in FIG. 4, light source 23 is positioned below the plane of fabric 10, at the edge 19 of the fabric and the pair of photoelectric cells 24 is positioned above the plane of the fabric 10, directly above the light source 23. With this arrangement, the pair of photoelectric cells will sense when the edge 19 of the fabric 10 is positioned between photoelectric cells 24a and 2412 since cell 24a will have the light beam from light source 23 blocked by the fabric 10 and cell 24]) will be exposed to the light beam. If the edge 19 is not disposed between cells 24a and 24b, either both cells will be exposed to the light source 23 or the light beam from light source 23 will be blocked from both cells.

If desired, the photoelectric sensing apparatus can be replaced by a mechanical feeler as shown in FIG. 5. Feel-er 112 is suspended from balancing arm 114 in a position where it engages the edge 19 of fabric 10. A wand 115 is rigidly connected to feeler 112 and extends in an upward direction from balancing arm 114. A pair of microswitches 116 and 117 is positioned on each side of wand 115, and the switches are electrically connected to solenoid control valves 83 and 84. With this arrangement, feeler 112 is firmly urged toward the edge 19 of fabric 10, and any irregularity in the edge of the fabric will cause feeler 112 to pivot about balancing arm 114. Pivoting of feeler 112 in this manner causes its wand 115 to close either microswitch 116 or 117, depending upon the direction of movement of feeler 112. Thus, the position of edge 19 of the fabric is determined by the mechanical feeler.

Operation In operation, the fringe cutting apparatus 9 is positioned with other material processing equipment in the path of travel of the fabric, either by mounting the apparatus directly onto the associated equipment or by supporting the stationary platform 34 from the fioor surface. The fabric is fed between tensioning bars 46 and 47, below tensioning bar 46 and over tensioning bar 47, and movable platform 38 is adjusted in its support members 35 and 36 so that cutting disc 31 is in the vicinity of the fringe 20 of the fabric 10. The contact roll 52 of driving mechanism 49 engages the upper surface of the fabric as it travels over tensioning bar 47, and the movement of the fabric causes contact roll 52 to rotate, which rotates flexible shaft 58 and causes anvil 29 to rotate. Contact roll 52 rotates in the direction as indicated by arrow 59 while anvil 29 rotates in the direction as indicated by arrow 30. It is desirable to rotate anvil 29 so that its surface contacting the bottom surface of fabric 10 moves at a linear velocity slightly faster than the linear velocity of fabric 10 to keep the fabric in tension. Thus, contact roll 52 is of slightly small diameter than that of anvil 29. If it is desired to rotate anvil 29 at a higher or lower speed, contact roll 52 may be made smaller or larger by adjusting the distance between discs 54 and 55, thereby changing the diameter of the elastic contact roll 52.

Air is ducted to manifold 60 from a compressor (not shown), and the air passing through manifold 60 is ducted to the various air ducts of the apparatus. The air passing through ducts and 16 impinges upon the fringe threads of the fabric in a direction to urge the fringe threads to stand laterally away from the fabric, generally in the same plane as the plane of the fabric. This tends to comb or straighten the fringe threads and to remove any tangles in these threads. As the fabric 10 continues to move in the direction as indicated by arrow 11, the air passing through duct 21 impinges upon the fringe threads in a direction generally normal to the plane of fabric 10, from above the fabric, so that the fringe threads tend to stand in a downward direction from the plane of the fabric. Light source 23 and the pair of photoelectric cells 24 are positioned closely adjacent to air duct 21 so that the light emanating from light source 23 will not be blocked by the fringe threads. Thus, photoelectric cells 24 determine the edge of the fabric without interference from the fringe threads.

As the fabric 10 continues to move in the direction indicated by arrow 11, air ducts 25 and 26 again urge the fringe threads to stand laterally away from fabric 10. Anvil 29 and cutting disc 31 are positioned close to air ducts 25 and 26 so that the fringe threads are received on anvil 29 as they extend laterally from fabric 10. As the fringe threads move over anvil 29, cutting disc 31 severs the fringe threads from fabric 10. The threads severed from the edge of the fabric are received in vacuum conduit 32 and removed from the area of anvil 29.

such that a minimum of drag or friction is encountered by the edge 19 of the fabric as the fringe threads are removed from the fabric.

As is shown in FIG. 4, photoelectric cells 24a and 24b are positioned above the edge 19 of fabric 10 while light source 23 is positioned below the fabric. If movable platform 38 is properly positioned so that cutting disc 31 functions to sever the fringe threads from the fabric at a proper distance from the edge 19 of the fabric, photoelectric cell 24a will be blocked from light source 23 by fabric 10 while photoelectric cell 24b will be exposed to the light. With any irregularity in the edge 19 of the fabric, such as a curve in the edge of the fabric, either photoelectric cell 24a will be exposed to light source 23, or photoelectric cell 2412 will be blocked from light source 23. When photoelectric cell 24b is blocked from light source 23, solenoid control valve 84 is energized and its control spool 104 is moved (FIG. 3) to block air duct 86 and allow air duct 102 to communicate with bleeder valve 109. This causes piston 90 to move in cylinder 88 away from the edge 19 of the fabric 10 to move movable platform 38 away from the edge of the fabric. Movement of platform 38 in this manner carries support frame 41 and its related components, including anvil 29, cutting disc .31, light source 23, photoelectric cells 24, and the air ducts away from the edge 19 of the fabric. Thus, cutting disc 31 is repositioned so that it cuts the fringe threads at the proper distance from the edge 19 of the fabric. As the movable platform 38 is repositioned, photoelectric cell 24b will again be exposed to light source 23, whereupon solenoid control valve 84 will be deactuated, its spring 110 moving its control spool 104 to the position as shown in FIG. 3, where air duct 86 again communicates with air duct 102. This tends to equalize the pressure on both sides of piston 90, thereby stabilizing linkage 94.

When the edge 19 of the fabric 10 is irregular and exposes photoelectric cell 24a to light source 23, solenoid control valve '83 will be energized to block duct and allow duct 101 to communicate with bleeder valve 109 of valve 83. Thus, the pressure from cylinder 88 will be bled through duct 101 and the pressure of the air present on the other side of piston 90 will move piston 90, linkage 94 and movable platform 38 toward the edge 19 of the fabric 10, thus repositioning cutting disc 31, anvil 29, and their related components. When photoelectric cell 2411 is again blocked from the light, light from light source 23, solenoid control valve 83 will again be deactuated, whereupon the system is again stabilized.

It should be noted that shafts 91 and 92 extend from both sides of piston 90, through the end walls of cylinder 88 so that equal areas are presented on each side of piston 90 for the air pressure within cylinder 88. Thus, equal air pressure present on both sides of piston 90 will exert equal forces on piston 90. Accordingly, when both solenoid control valves 83 and 84 are deactuated and in their open position so that the source of air pressure communicates with cylinder 88 on both sides of piston 90, the system will be stabilized and there will be no movement of movable platform 38. When one of the solenoid control valves 83 or 84 is actuated to block the source of air pressure to one side of piston 90, the rate at which the air from cylinder 88 escapes through its solenoid control valve will be determined by the adjustment of the bleeder valve 109 of the solenoid control valve. Thus, if the fabric 10 is moved at a high rate of speed and there is a short distance between photoelectric cells 24 and cutting disc 31, bleeder valves 109 should be adjusted so that the air can be bled from cylinder 88 at a rapid rate so that there will be little delay in repositioning cutting disc 31 when an irregularity is determined by photoelectric cells 24. Of course, if fabric 10 is processed at a slower rate, bleeder valves 109 can be adjusted to restrict the flow of air therethrough so that the air is bled more slowly from cylinder 88, thus providing a longer delay time in repositioning cutting disc 31.

Linkage 94 between cylinder 88 and movable platform 38 is such that a large movement of piston 90 is required to move platform 38. Pivot pin 99 can be positioned in any of the apertures present in pivot link 95 to vary the amount of movement necessary of piston 90 to move platform 38 a given distance. Under normal circumstances, it is anticipated that a three to one or four to one linkage will be utilized, thus requiring four inches of movement of piston 90 to achieve one inch movement of movable platform 38. With this arrangement, fine control is maintained over the movement of cutting disc 31.

Photoelectric cells 24a and 24b are spaced apart a distance calculated to prevent searching or hunting of the system; that is, to keep the fringe cutting apparatus from oscillating back and forth during its cutting function due to over-compensation of the automatic controls of the system. Photoelectric cells 24a and 24b are mounted in a disc which is supported by support bracket 72 so that the disc can be rotated to change the position of photoelectric cells 24a and 24b. While the photoelectric cells are shown in FIG. 4 as being disposed with respect to each other along a line extending transversely with respect to the edge 19 of fabric 10, the disc can be rotated to effectively bring the cells closer to the edge 19 of the fabric, thus effectively reducing the distance between the cells. When the cells are oriented in this manner, a smaller variation in the smoothness of the edge 19 of the fabric will cause a repositioning of the fabric cutting apparatus. As applied to the mechanical feeler of FIG. 5, a similar function can be achieved by moving microswitches 116 and 117 closer to or further away from each other.

At this point, it should be apparent that the manner in which the air is blown over the edge of the fabric is effective to first comb or straighten the fringe threads, secondly to blow the fringe threads in a direction normal to the plane of the fabric so as to expose the true edge of the fabric, and thirdly to re-orient the fringe threads so that they extend laterally from the fabric and are easily cut by cutting disc 31. The use of photoelectric cells 24 is such that the true edge of the fabric can be determined without making physical contact with the edge of the fabric. If it is desired to cut the fringe threads closer to or further away from the edge of the fabric, all that is necessary in making this adjustment is to extend adjustable arm 75 of support bracket 74 further away from or closer to leg 45 of support frame 41, which repositions photoelectric cells 24. This causes the anvil 29 to shift the edge of the fabric with respect to the cutting disk 31 since the cutting disk 31 does not move rapidly with respect to the fabric. Thus, cutting disc 31 will be efiective to leave a longer or shorter fringe at the edge of the material.

While air ducts '15 and 16, and 25 and 26 have been shown as blowing air from above and below the fabric, the use of only a single duct or 16, or 25 or 26 is suflicient in most instances to achieve substantially the same function since the air flow over only one surface of the fabric is sufficient to induce the fringe threads to stand outwardly from the fabric 10. Also, while air ducts, 15, 16, 21, 25 and 26 have been disclosed as blowing air over the surface of the fringe, it should be understood that any one or all of these ducts oriented can be replaced with vacuum ducts to induce an air flow in a similar manner. The use of vacuum ducts with some types of materials has the advantage of removing lint and loose threads from the vicinity of the fringe cutting apparatus. Also, while ducts 15, 16, 21, 25 and 26 have been disclosed as air ducts, it should be understood that other fluids may be utilized in these ducts to perform substantially the same function.

While anvil 29 has been illustrated as being driven by driving mechanism 49, it should be understood that in some installations it may be desirable to drive anvil 29 by direct linkage to the drive system of the associated equipment. A linkage of this type can be utilized without detrimental effect on the remaining components of the system.

It will be obvious to those skilled in the art that many variations may be made in the embodiments chosen for the purpose of illustrating the present invention.

We claim:

1. A method of cutting loose threads along the edge of a moving fabric comprising:

(a) extending the loose threads in a direction generally normal to the plane of the fabric;

(b) sensing the true edge of the fabric at the base of the loose normally extending threads to properly determine the cutting position;

(c) urging the loose threads away from the fabric in a direction generally coextensive with the plane of the fabric to properly position such threads for cutting; and,

((1) cutting at least a portion of the length of the loose threads from the fabric, the cutting position being modified in accordance with the sensing whereby the cutting of the threads is maintained at a predetermined distance from the true edge of the fabric.

2. The method of claim 1 wherein step (a) is performed by discharging a stream of fluid against the loose threads in a direction generally normal to the plane of the fabric.

3. The method of claim 1 further comprising the step of extending the loose threads away from the fabric in a direction co-extensive with the plane of the fabric prior to step (a) to unsnarl the loose threads.

4. The method of claim 1 wherein step (c) is performed by discharging a first stream of fluid against the loose threads above the plane of the fabric in a direction generally parallel to the plane of the fabric and simultaneously discharging a second stream of fluid against the loose threads below the plane of the fabric and in a direction generally parallel to the plane of the fabric.

References Cited UNITED STATES PATENTS 410,655 9/1889 Smith 26-104 1,973,104 9/1934 Richardson 26-104 2,110,567 3/1938 Burr 2610.4 2,962,791 12/1960 Remington 2610.4 3,409,955 11/ 1968 Holm 26-104 ROBERT R. MACKEY, Primary Examiner US. Cl. X.R. 139-302

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