US2883710A - Stop motion - Google Patents

Description

April 28, 1959 G. A. MOBLEY STOP MOTION 2 Sheets-Sheet 1 Filed March 12, 1953 Inlv INVENTOR Geollge A NobLey ATTORNEY April 28, 1959 G. A. MOBLEY STOP MOTION Filed March 12, 1953 Y 2 Sheets-Sheet 2 4 INVENTOR. G'eogge A. Mob/2y Y wdza 57M ATTORNEY United states Patent STOP MOTION George A. Mobley, Fork Union, Va., assignor, by mesne assignments, to Deering Milliken Research Corporation, near Pendleton, S.C., a corporation of Delaware Application March 12, 1953, Serial No. 341,959

3 Claims. (Cl. 19-165) This invention relates to stop motions for strand handling machinery and is directed particularly to a stop motion for textile equipment wherein two parallel strands are handled or processed. Representative of those machines with which the present invention is especially adapted for use is a pin drafter, such as is manufactured and sold by the Warner and Swasey Company of Cleveland, Ohio, and it is in association with this machine that this invention will be illustrated and described, although it will be appreciated that this invention is capable of much more universal application. In fact, my stop motion is not necessarily limited to textile machines but could be satisfactorily associated with any machine which is designed for the passage therethrough of pairs of traveling parallel strands of funicular material.

In some applications of the pin drafter, two parallel strands of sliver, wool top or the like emerge from a final set of drafting rolls or delivery rolls into a pair of horizontal trumpets spaced a short distance from the final rolls and supported on a bracket mounted on the dome of a coiler head. The strands proceed from the trumpets into a single guide eye at the apex of the coiler head dome from which they are fed into a coiler can supported by the head and slowly rotated to deposit the strands inside the can in a uniform and orderly manner.

Any loosely associated material, such as wool top or sliver, is, of course, subject to rupture and in a pin drafter rupture is most likely to occur in the region between the final pair of draft rolls and the trumpets. When one strand breaks, it continues to be fed by the draft rolls and thus accumulates or builds up between the rolls and trumpets. If this accumulation is allowed to proceed, it tends to be drawn back into the rolls where it becomes entangled with the rolls and the oncoming strand, causing breakage of the faller combs with extensive damage to the machine. Even if the lap up, as this occurrence is known in the art, is detected before any considerable damage has taken place, removal of the entanglement is a difiicult and tedious operation and, consequently, the unit is out of production for a considerable period of time. Further, the mass of material which has collected generally becomes contaminated with dirt and grease and cannot be easily salvaged for reprocessing.

It is therefore most desirable to equip machines of this type with means for detecting rupture of either of the strands between the final drafting rolls and the coiler head trumpets. Nor is a simple mechanical feeler, as has heretofore been used, adequate for this purpose. It frequently happens, through some quirk of circumstance, that an end comes down in such a fashion that it is not detected by a simple feeler as, for example, when the rupture occurs within the trumpet and the accumulation takes place at such a rate and in such a manner as to maintain the feeler in its normal position. In this case, an obvious desideratum would be a detecting means equally capable of sensing the accumulation of material and operating when the accumulation exceeds a certain level.

The prior art structure was also deficient in that the contact bars with which the feeler made electrical contact at the rupture of a strand were exposed to the surroundings. As a result, the natural greases in wool top or the sizing composition on other materials applied to the yarn was deposited on the bar and feeler preventing positive electrical contact and, thus, making operation of the device most erratic.

It is therefore the object of this invention to provide a stop motion for machines processing parallel strands of funicular material which is capable of sensing both the rupture of the strands and an abnormal accumulation of material in the locality of the stop motion and of shutting off the machine in response thereto.

A further object of this invention is to provide a stop motion for detecting the breakage of either of two traveling parallel strands either by reason of the initial rupture or by the inability of the machine to withdraw the strand from the point of rupture due to lack of continuity.

Another object of this invention is to provide a strand breakage detector which functions to detect a slub or a section of enlarged cross section in the strand.

A still further object is to provide depression sensitive elements contacting parallel strands of moving material which are mounted for rotation about a common axis and are partially coupled together for unitary movement in an upward direction and for independent movement in a downward direction.

An additional object is to provide electro-mechanical stop motion having those electrical components which are proximate to the material being processed completely enclosed against fouling by grease and foreign matter.

Other and further objects and advantages of this invention will be apparent from the following detailed description when read in connection with the drawings in which:

Figure 1 is a plan view of the novel monitoring unit of my stop motion in association with related parts of a pin drafter;

Figure 2 is a right side elevation;

Figure 3 is a detailed front view of the novel monitoring unit in normal operative position;

Figure 4 is a view similar to Figure 3 but showing the unit detecting rupture of one strand;

Figure 5 is a view similar to Figure 3 but illustrating the detection of a slub;

Figure 6 is a circuit diagram of my invention; and

Figure 7 is an exploded view of the strand contacting fingers and pivot pin.

In general, my invention comprises a pair of switch bars mounted for pivotal movement about a common axis, each being adapted for floating engagement with one of a pair of parallel strands of funicular material, such 'as wool top, sliver or the like. Associated with each of the switch bars is a depression sensitive switch means which is electrically connected to a motor control circuit, regulating the motor of the machine. The ends of the switch bars adjacent the common axis are constructed for partially co-acting operation whereby they function as an integral unit upon movement of either of them in an upward direction but as separable elements upon movement of either of them in a downward direction.

With reference now to Figures 1 and 2, the numeral 11 designates the bottom roll of a final pair of draft rolls of a pin drafter and the numeral 13 the top roll. Spaced from the final pair of draft rolls is a conventional coiler head generally indicated by the numeral 15. A guide eye 17 is situated at the apex of the coiler head dome 19 and mounted adjacent the guide eye 17 is an L-shaped bracket 21 which supports a pair of horizontally disposed spaced parallel trumpets 23.

As is well known in the art, two parallel strands of wool top, sliver, or the like S pass through the top and bottom rolls 11 and 13 to the trumpets 23, thence to the guide eye 17 where they are combined into a single strand, and are finally fed by the coiler head in a well-known manner into a coiler can (not shown) associated with the head 15.

Having thus described the related elements of a conventional pin drafter, I will now proceed with a description of the details of my particular improvement.

There is rigidly secured to the lip-standing portion of the L-shaped bracket 21 at substantially the mid-point thereof one end of a horizontally extending support rod 31 which projects in the direction of the rolls 11 and 13 and carries at its extreme end a vertical plate 33. The plate 33 is suitably apertured and threaded for the threaded end of a stub shaft 35.

In order to sense the presence of the strands S, I make use of a pair of switch bars 37 which are mounted for pivotal movement about the stub shaft 35, having an aperture 39 provided therein through which the stub shaft 35 extends. The switch bars 37 extend in substantially diametrically opposite directions from the axis of the stub shaft 35 and are adapted to normally float or ride upon the top of the strands S.

As may be seen in Figure 7, each of the switch bars 37 is preferably formed with a hollow tubular portion 41 which makes up the greater part of its length, and an offset solid portion 43 in which is formed the aperture 39. Intermediate the tubular portion 41 and offset portion 43 is a thin, square, plate-like section 45 which is normal to the axis of the bar. The end of the offset portion 43 remote from the tubular portion 41 is preferably rounded at its lower corner, as at 47, and is partially cut away at its upper corner to provide a slightly inclined surface at this point, as is indicated by the numeral 49.

As is best shown in Figures 3 and 7, when the switch bars 3'7 are assembled with the stub shaft 35, the offset portions 43 are in overlapping or juxtaposed relationship and the shaped end of the offset portion 43 of each of the bars 37 is closely adjacent to the inner face of the platelike element 45 of the other of the bars.

Housed within each of the switch bars 37 and sealed therein by any suitable means, is a mercury switch shown in dotted fashion in Figure 3 and generally indicated by the numeral 51, the switch having the usual pair of contacts 53 and globule of mercury 55. Connected to the contacts 53 are two sets of electrical conductors 57 which pass through a hole 59 drilled in the upper end of vertical plate 33 and are provided at their free ends with terminal lugs 61. One terminal lug of each of the respective sets of conductors is connected to one of two terminal blocks 63 carried by the horizontal rod 31 intermediate the bracket 21 and the vertical plate 33, each of the blocks 63 having a single electrical lead 65 connected thereto which joins with the motor control circuit as will hereinafter he described in greater detail.

The mode of operation of the switch bars may be best understood from a consideration of Figures 3 through 5. in Figure 3 the normal operating position is shown with the switch bars riding upon the sliver S and in a slightly elevated position. In this position the globule of mercury 55 is remote from the contacts 53 and, thus, current cannot flow through the switch 51. Should one strand of sliver S happen to rupture, however, the rounded lower corner 47 of the switch bar 37 riding upon that strand permits the bar to rotate about the stub shaft 35 independently of the other switch bar, causing the mercury to flow down around the contacts 53, and completing the circuit. On the other hand, should a slub or enlargement in a strand of the sliver happen to pass beneath one of the switch bars as indicated at S, the bar is caused to tilt upwardly about its pivot axis as depicted in Figure 5. As the extent of tilt exceeds a fixed point, determined by the angular inclination provided at the top of the corner of the offset portion 43 of the switch bar in question, the inclined face of this corner abuts against the inner face of the square element 45 of the other switch bar and further elevation of the one switch bar results in a depression of the other switch bar sufficient to actuate the mercury switch 51. Although not illustrated, it will be understood that the action of the switch bars during a lap-up or abnormal accumulation of sliver is similar to that shown in Figure 5 in that the build-up of the sliver elevates one switch bar and depresses the other.

The electrical circuit by means of which the switch bars 37 control the pin drafter is diagramrned in Figure 6. A main line having two sides or leads 71 and 71 which is capable of interruption by means of a disconnect switch '73 connects a source of alternating current, not shown, with the motor 75 of the pin drafter. In series with the two sides 71 and 71' of the main line are two armatures 79 and 80 of a three-armature relay generally designated 77. The coil 83 of the motor relay 77 is connected on one side to the main lead 71 through the armature 35 of a control relay 87 and a normally closed push button switch 89 and on the other side with the other main lead 71 through a parallel connection including a normally open push button switch 88 on the one hand and the third armature 81 of the motor relay 77 on the other. The coil 93 of the control relay 87 connected to the side 71' of the main line is connected to the mercury switches 51 arranged in parallel and connected to the other side 71 of the main line.

The operation of the electrical components of my invention is as follows:

To start the machine, the operator closes the normally open push button switch 88 which permits current to flow to the coil 83 of the motor relay '77 closing the three armatures 79, 80 and 81, thus supplying current to the motor 75. Since the coil 83 of the motor relay '77 is connected through the armature 81 to line 71 and through armature of control relay 77 to line '71, the coil 83 remains energized after release of the push button switch 83. Upon the actuation of either one of the mercury switches 51 due to an abnormal condition occurring in the sliver S, the coil 93 of the control relay 37 is energized, opening the armature 85 of the control relay and interrupting the supply of current to the motor relay 77. This permits the three armatures 79, 80 and 81 of the motor relay to reassume their normally open position, shutting oif the flow of current to the motor 75.

As the pin drafters and other machines of this general class will vary slightly from machine to machine, I prefer to defer the shaping of the upper, inner corner of the switch bars until after they have been assembled on the drafter. The corner can then be shaped by means of a common file or the like to that angle which best suits the particular requirements of a given machine. Obviously, for the functions of slub and accumulation detection, the sensitivity of my invention will depend upon the angle of inclination from the vertical given the top corner of the switch bar. Thus, by varying the angle of inclination, greater or smaller slubs or accumulations will be permitted before the stop motion is actuated.

Preferably, the switch bars 37 are so mounted that their normal operating position is slightly below the usual path of travel of the slivers between the feed rolls and the trumpets in order that the slivers are somewhat deflected from such path. This causes the normal running tension in the slivers to bias the bars upwardly with the result that, in the event one sliver does rupture, the tension in the remaining strands assists in moving the finger sensing the ruptured strand to its actuating position, thus contributing to the fail-safe operation of my invention. This location of the bars is also beneficial in lending stability of the operation of the device. As both bars are urged upwardly and thus function as a unit, the tension in the slivers operates to eliminate bouncing of the bars, thereby preventing the opportunity for a false actuation.

It will be apparent to those versed in step motions that I have provided a device which is simple in design, virtually foolproof in operation, rugged enough in construction to withstand hard treatment, does not interfere with the normal operation of the machine, may be easily repaired, can be constructed at low cost and which is efiective to monitor pairs of moving strands and supply a control signal upon the occurrence of an abnormal condition in the strands. I

As the specific details of my invention are clearly capable of modification by one skilled in the art, I do not choose to be limited to the single embodiment shown and described, but only by the scope of the claims hereunto appended. I

Having thus described my invention, that which is claimed is:

1. The combination with a machine for processing traveling parallel strands of funicular material including means for driving the same, of a pair of'fingers mounted on said machine for pivotal movement about a common axis, each of said fingers being in floating engagement with one of said strands, said fingers being formed with cooperating surfaces thereon permitting free 2. The combination of claim lwherein said fingers pair of traveling parallel strands of funicular material,

of a pair of hollow tubular members having one end thereof pivotally mounted on said machine about a horizontal axis extending intermediate the paths of said strands, said connected ends being closely contiguous, said members extending in generally opposite directions from said axis and adapted for floating engagement with said strands, stop means carried by each of said members for limiting pivotal movement thereof relative to the other of said members in an upward direction while permitting relative downward movement, switch means housed within said members for detecting downward movement and electrical means actuated in response to said switch means for controlling said machine.

References Cited in the file of this patent UNITED STATES PATENTS 190,127 Bullough May 1, 1877 1,892,116 Parker Dec. 27, 1932 1,920,767 Scott a Aug. 1, 1933 2,405,218 Lambach et al. Aug. -6, 1946 2,645,822 Cabana July 21, 1953 FOREIGN PATENTS 30,157 France Mar. 29, 1926 (1st addition to No. 590,677) 342,128

Great Britain Ian. 29, 1931

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