US2523184A - Seam detector - Google Patents

Description

sePt- 19, 1950 H. w. BEALL 2,523,184

sEAM DETEoToR Filed May 6, 1949 2 Sheets-Sheet l ATTORNEY H. W. BEALL SEAM DETECTOR sept. 19, 195o 2 Sheets-Sheet 2 Filed May 6, 1949 I N VEN TOR. /efiwell Patented Sept. 19, 1950 SEAM DETECTOR Herbert W. Beall, Lancaster, S. C., assignor t The Springs `Cotton Mills, Lancaster, S. C., a corporation of South Carolina Application May 6, 1949, Serial No. 91,829

2 Claims. l

My invention relates to a seam detector for use in connection with the handling of long lengths of cloth that are made up by joining shorter lengths by sewing a seam across the run of the cloth thereby joining adjacent end portions. These seams may be lapped seams or at seams or mixed. In tearing these long lengths into shorter lengths to make sheets, etc., it is desirable to `arrange the varying lengths of cloth into which sheets may be made so as to make the seam fall near or adjacent the end of a sheet so that the seam may be torn out with the minimum of waste.

In order to avoid such Waste it is necessary to Warn the operator some time in advance of the approach of a seam. It is therefore customary to provide a maze through which the cloth passes and which will hold a definite length of cloth so that the operator may be informed of the number of the various lengths of sheets that can be torn, and have the seam fall adjacent the last sheet. It is not possible to do this unless the sheets vary in standard lengths, such as 108", 99" and 90". For informing the operator of the approach of a seam it is usual to use a seam detector with a signal device or a trip mechanism that stops a motor and so to stop the feeding of the cloth.

My present invention is an improvement on present seam detectors. run one layer of cloth through the detector it is often desirable to use the detector on folded cloth where two or more layers pass through the detector.

It is an object of my invention to provide a seam detector which will operate on multiple layers of cloth.

Another object is to provide easy and accurate means for adjusting the gap in the detector even while the cloth is in motion, if desired.

Another object is to provide an indicator to assist in setting the said gap in the detector, through which the cloth travels.

Another yobject is to provide means for preventing tears in the cloth when a slub or thick place in the cloth comes into contact with the points.

Another object is to provide means for easy insertion of the cloth between the points of the seam detector.

Referring now to the annexed drawings, which are made a part of this application and in which similar characters of reference indicate similar parts:

Fig. 1 is a perspective of a length of cloth Although it is usual to 2 having portions connected at their adjacent ends by means of seams and also having diagonal wrinkles.

Fig. 2, a transverse section of the machine, showing my improved detector in position thereon,

Fig. 3, a wiring diagram,

Fig. 4, a top plan of a screw shown in Fig. 2,

Fig. 5, a side View of a modification, and

Fig. 6, a detail of a feeler forming part of the same, on an enlarged scale.

In the drawings, reference character I0 indicates a folded sheet of cloth comprising a plurality of loom lengths connected at adjacent ends, preferably by conventional fiat butt seams Il, such as are made by Wilcox & Gibbs sewing machines and others for connecting edges of cloth without forming thick seams, which are undesirable for various reasons. If the cloth is moving in the direction of the arrow in Fig. l, wrinkles or folds such as are indicated at I2 will be formed therein. A seam detector including clothengaging renewable wear buttons I3, I3, is positioned crosswse of' the strip of cloth, as indicated in Fig, l, these buttons being made of hard rubber, or suitable plastic or other material. In the form of the invention here disclosed the buttons are mounted upon reduced lower end portions of rods I4 and are so located as to press the upper surface of the cloth, against a pressure bar I4 attached to a fixed part I4 of the machine.

The essential feature of the invention consists in the use of a plurality of feelers in a rowcrosswise of the cloth or nearly in a row, the actual preferable number being dependent on the width of the cloth, the weight of the cloth, etc. Each feeler includes a button, a switch member, and means for supporting them in constant relation to one another or substantially so. As stated, the number of feelers depends somewhat on the characteristics of the cloth to be torn, for the best results, but what is essential is that there shall be a plurality of such feelers if multiple layers of cloth are being operated on.

It is obvious that when only one feeler is used in a transverse row a diagonal Wrinkle or fold will be just as effective to operate the feeler as a sewed seam provided that the wrinkle stands up suiiiciently above the level of the cloth, though a single feeler may be effective under conditions discussed hereinafter. With my new arrangement of a plurality of feelers in a row actuation of a single feeler will have no stopping or signaling effect; only upon actuation of all the feelers in a row will stopping or signaling be effected.

The rods I3 and their buttons are preferably three in number for any ordinary conditions and the rods are mounted for vertical sliding movement in bearings I5 on the bottom member I6 of a casing which is shown as enclosing the principal parts of the seam detector. A bar I1 is fixed in place in an upper part of the casing, and the rods I4 are arranged to slide in apertures in the bottom of the casing and in bar I1. Springs I8 surround the respective rods I4, said springs bearing at their upper ends against bar I1 and at their lower ends against collars I9 on portions of rods I4, the adjustment of said col-- lars varying the compiession of the springs and so varying theii resistance to upward movement of the respective rods. The springs press the buttons down against the cloth and the bar I4.

At. their upper ends the rods I4 are provided with collars 2l!` that support rings 2| of electrically conductive material. Blocks- 22 mounted on the bar I1 support contacts 23, 24 for engagement with rings 2I, the contacts 23 being in permanent engagement with their rings and the contacts 24 being resilient and being normally spaced apart from such rings to an extent that is predetermined in accordance with the necessitiesof the particular machine or the cloth passing through it for tearing into lengths or for any other purpose.

The adjustment of the movable contacts is effected by means of screws 25 having threaded engagement with nuts 25 that may be formed integrally with the casing of the detector, and ga locknut 25 is provided upon each screw for hold-ing it in adjusted position. Screws 25 have insulating pads 25a at their lower ends and extend outside the casing. Thus they can be adjusted whether the machine lis running or not. It will be lseen that the screws can all be adjusted by the help of a neonvlamp together with the seal-e marks on the heads of the screws and a unit mark on an adjacent xed surface so as to close the contacts. and that by appropriate manipulation each. screw may beset so as to hold its contact 24 very exactly at the amount of opening suited .for .moving its circuit closer upon occurrence of a seam in cloth of the weight and thickness being handled. Conventional conductors 28, 29 carry. current to thev contacts above mentioned.

Switches 30, 3U, 3l]A are provided to short circuit two of the pairs of points, while the other is being adjusted. For instance, two switches are first closed and the other two points are then also closed by turning down their screw 25 until the neon lamp goes out, as the current now passes through the points. The screw is now turned counterclockwise until the lamp again lights up, and the screw is turned a small additional amount to clear thick places such as may occur in the cloth. This additional amount may be determined by means of the reference marks shown in Fig. 4. The other points are adjusted in like manner by opening another switch and closing the one that was previously opened.

When the points are closed the current flows through the solenoid which interrupts the motor circuit, or a relay that operates a signal device such as a bell, a light, etc. Since the seam passes the detector very quickly it is not practical to rely on seeing a signal or hearing a signal and then stopping the machine manually, but it is necessary to use an automatic trip which is afterward reset manually or else automatically at the end of a cycle. Such a trip is shown at 33a.

The seam detector may be used in a cloth tearing machine of the type disclosed in my patent application Ser. No. 779,513, filed October 13, 1947.

The buttons I3, I3 are pressed against the cloth bythe springs I8, I8, the cloth being supported by the pressure bar I4', as above stated. The movement of the buttons is from .004" to .015 when raised by a passing seam, the amount of the lifting depending on Whether the seam is a lapped seam or a butt seam. The feelers are in series with each other and with the relay. If only one of the detectors is raised to cause its contacts to engage, as by a diagonal fold or wrinkle, the rod Will simply descend to its original position after the fold has passed, but if all the detectors of a row are raised by a transversely extending seam the relay shown at 33 will be energized, breaking the motor circuit of motor 32, and the motor will stop runtil the relay is reset, it being understood that the relay remains open until reset manually or by automatic action at the end of a cycle. At this time the signal lamp will be short circuited and the light will go oii iand on very quickly, i. e., for about 1/50 second. When the seam has been moved past the detectors they descend and the lamp lights up again but the relay will remain tripped.

Since the adjustment of the detectors must be very accurate, as for multiple folds of thin cloth, I provide very accurate means for making the adjustments above described. A detail of a modified Ipush rod is shown in Fig. 6. In this form it comprises a hollow stem 43 and a telescoping upper shaft 41 that is slotted at 46 near its lower end to receive a pin that extends across the hollow stem. A spring 58 urges the shaft 41 upward so far as permitted by the pin, after which the entire push rod is forced upward by irregularities in the cloth to force the contact 49 against contact 50. If the irregularities are abnormally high spring 58 will yield, allowing the cloth to pass without tearing it. A collar 44 on the hollow stem prevents the stem from falling through its hole in the casing when the device is being assembled and also takes the pressure of the spring, if a spring is used to produce pressure on the cloth, The collar never touches the casing unless the detector unit is being taken apart, but is held up by the cloth and forced down by the spring against the cloth if there is cloth in the machine. The contact springs 50 may be made strong enough to press the buttons against the cloth, if desired.

The bracket 34 supports a box consisting of an upright 39, horizontally extending members 31 and 38 parallel to each other, an outer end upright 40 and a removable top cover supported on upwardly extending portions ofthe end members 39 and 40 by means of screws 42, 42. The 1ntermediate horizontal bar 38- has a bearing in line with that in lower bar 31 for the push rod, which member also limits the movement of the push rod by engaging the collar 44, and the bar 38 supports a block 5I for carrying the resilient contacts 49 and 50, which are attached to conductors 52 in a socket 53 that has a neon lamp mounted therein, and conductors 54 leading to a control means, as in Fig. 3, Means for adjusting the upper contact 50 relatively to the lower contact 49 consists of a screw 55 adjustably mounted in a fixed nut 56, and a locknut 51. The screw has an insulating pad 55' at its lower end t0 engage the upper contact, and as the screw extends outside the casing the contacts can be manipulated whether the machine is running or not.

The head of the hollow stem constitutes the cloth-engaging button, and is shown as integral with the hollow stem, but may be removably attached, as in Fig. 2. An insulating plug 48 is mounted in a recess at the upper end of the push rod.

The relay is in circuit with the contacts 49 and 50 and when they are brought together the solenoid will be energized so as to close the relay and stop the motor until the relay is reset. Impedance of the relay is such that a normal amount of current passes through the contacts. When the neon lamp is connected across the contacts it will light up without energizing the solenoid, since its resistance is very high. If the points are now brought together the neon light will go out and the relay will be energized to break the motor circuit. No current can flow through the neon light at this time since it is short circuited due to the fact that the -contacts 49 and 50 are engaged t0 close the circuit at that point.

To set the button so that it will press the face of the cloth, While yet the contacts are open, the screw 55 isrotated to bring the contacts together. The light now is extinguished. When the screw is backed oi until the position of the contact is such that it just permits the light to go on again a small additional movement of the screw will set the button `at the most advantageous level.

It will be obvious to those skilled in the art that many changes may be made in the devices herein disclosed, all without departing from the spirit of the invention; and therefore I do not limit myself to what is shown in the drawings and described in the specification, but only as indicated in the appended claims,

Having thus fully described by invention, what I claim is:

1. Means for detecting a seam in a traveling strip of material, comprising a plurality of circuit closers arranged in a line substantially across the path of the strip, and means operable only upon simultaneous closing of all the circuit closers for indicating the occurrence of a seam.

2. A seam detector for sheet handling devices, comprising a supporting member over which the material travels, a plurality of feelers contacting the material and arranged in a series extending transversely of the travel of the material, and an electric circuit including a plurality of contacts in series said contacts being operable by said feelers.

HERBERT W. BEALL.

REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS Number Name Date 869,324 Obert Oct. 29, 1907 1,149,018 Beregh Aug. 3, 1915 2,091,522 Perry Aug. 31, 1937 2,402,312 Burch June 18, 1946

Images