US1722277A - Automatic stop for sewing machines - Google Patents

Description

July so, 1929. c. A. COUCH ET AL 1,722,217

AUTOMATIC S"J.O1 FOR SEWING MACHINES Filed March 30, 1928 INVENTOR5 ATTORNEY Patented July 3Q, 1923.

metres stares earner castes- CHARLES A. COUCE AND SAMUEL P. EATCI-IER, OF WARE SHOALS, SOUTH CAROLINA, ASSIGNOBS TO WARE SHOALS MANUFACTURING COMPANY, OF WARE SI-IOALS, SOUTH CAROLINA, A CORPORATION OF SOUTH CAROLINA.

AUTOMATIC s'ror roa SEWING MACHINES.

Application filed March 30, 1928. Serial No. 265,936.-

This invention relates to an attachment for sewing machines, more particularly machines employed in hemming pillow cases and the like, whereby the machine will be automatically and promptly stopped when ever from the breaking of the thread or other cause the hem is not being sewed.

In the manufacture of certain articles,

such for example as pillow cases, it has long been customary to first cut or tear the material into the necessary lengths, then to fold and seam one side and one end thereof, and finally to hem the open ends.

We have sought to improve upon such practice, and thereby to reduce the cost of manufacture, by firsthemming the material in the piece, before it is cut up into lengths and folded. To this end, a bolt of cloth is run from a roll through a sewing machine, which folds and stitches the hem on one side ofthe piece, and thence to a folding device by which the hemmed piece is piled up in folded lengths. Much trouble and delay was, however, experienced in stopping the machine whenever, due to a breakage of the thread or otherwise, the folded hem was not being properly sewed down and in returning the piece tothe point at which the failure occurred, especially as the failure might not be noticed for some time in case the machine was not being closely watched. Our present invention, by providing a means for stopping the machine before a piece has been carried more than a few inches beyond the point of failure, has not only largely obviated this difficulty but also makes it possible to run the machine at a higher speed and with lesscare and attention than was otherwise practicable.

The new stop attachment comprises, briefly stated, a detector movably mounted to ride upon the material being hemmed at a point slightly behind the needle of the machine, which detector normally bears lightly against and is held'by the edge of the hem and is operative whenever the hem is not being sewed down to slide forward within the hem, and means controlled by such movement for shutting down, or disconnecting, the power used. to drive the machine. f

Gne practical. embodiment of the invention is shown, by way of illustration and not against the edge of a hem; Fig. 2 is a view I similar to Fig. 1 but showing the -position assumed by the parts when the detector has moved within the hem when left unsewn; and Fig. 3 is an enlarged detail, also in perspective, of the clutch-lever holding and releasing mechanism.

Referring to the drawings, 5 indicates a standard, or any suitable, sewing machine, and 6 a portion of the piece of cloth which is being hemmed thereon; and 7 is the upper end of the lever which, as customary, controls a clutch (not shown) by which both the sewing machine and the mechanism (also not shown) for feeding the piece of goods and as hemmed piling-it up in folded lengths are operatively connected with and disconnested from the power shaft. To throw in the clutch, to start the machine and associated mechanism, the clutch-lever is-swung,

I to the right as shown, to a substantially vertical position and is there held by a catch 8 which is mounted to slide in guides in a bedplate 9 and is pressed back against the action of a spring 10 by the engagement of the lever with its inclined outer end 11 as the lever is swungup and then springs out behind it to lock it in place. On the withdrawal of the catch, the lever is released and is swung back, as by a sultable spring (not shown) and thereby throws out the clutch and stops 1 the machine.

' In the specific embodiment here shown, the withdrawal of the catch, to release the clutch-lever and throw out the'clutch, is

automatically efl'ected under the control of a detector which is in turn controlled by the operation of the machine, as follows:

The detector 12, with end 13 tapered and beveled to a blunt point, issecnred to and carried at the end of the depending for ward'arm of bent rod 14:, which support:

ed and slides in a notch 15 in the lower side of an open slot in a bracket 16 secured in any suitable manner, preferably adjustably, to the head of the machine. Fixed to the rod 141, adjoining the bend therein, is an additional shorter bent rod17 providing a spaced parallel length which slidingly bears in a notch 18 in the lower side of a second slot in the bracket 16 and serves not only to reinforce the rod 141 but to hold its dependent arm substantially perpendicular and so prevents the detector from being shifted laterally by its contact with the moving piece of material upon which, thus slidingly supporte ed,it rides lightly. At its other or rear end the rod 14 is connected, at 19, to one arm of a bell-crank 20 pivotally mounted by a stud 21 on a shaped bracket 22, secured to the upright standard of the machine, which provides at its upper side a projecting stoplug 23 and at its lower side a lug 24 to which is attached a light spring 25 connected at its other end to the downwardly depending arm of the bell-crank. The upper arm of the bell-crank is in turn connected by a link '26 to the end of an arm 27 with shaped head 28 pivotally mounted at 29, to swing its head into and out of the path of a cam 30 which is made as an inte ral part of or is suitably attached to the fly-wheel of the machine, upon an ear or lug 31 carried at right angles thereto by a lever 32 pivotally mounted at 33 on a shaped bracket 34 also secured on the upright standard of the machine. The lower end of the lever 32 is operatively connected by a link 35 with a trip-lever 86 which is pivoted at 37' on the bed-plate 9 and has a rounded outer end operatively bearing against a lug or shoulder 38 carried by the catch 8.

In operation, on starting the-hemming of a piece of goods, the detector is moved outwardly and set with its point bearing against the edge of the hem, thus raising the head of the arm 27 out of the path of the cam on the fly-wheel, and it will be so held and will in turn hold the arm in inoperative position as long as the hem is being properly sewed down. Should the thread break, however, or should the machine cease to function properly, as where the line of stitches runs off the edge of the hem for instance, the end of the detector will at once be drawn within the folds of the unsewn hem, by action of the spring 25, and the head of the arm- 27 will drop into the path of the cam on the flywheel of the machine. Thereupon, on the first revolution of the fly-wheel, the cam will engage the head of the arm 27 and, moving it outwardly, will throw out the upper end of the lever 32, which in turn will swing the trip-lever 36 to force back the catch 8 and release the clutch-lever.

It will be seen that the power required for thewithdrawal of the catch, to release the clutch-lever, is supplied by the'machine itself. The detector merely serves by its position to control the position of the arm 27. Hence, the pressure with which the point of the detector is held against the edge of the hem is merely sufiicient to insure the required movement of the detector in case of a failure. The spring 25 may therefore be omitted, if desired, as the weight of the arm 27 will usually be, or may be made, sufficient for the purpose.

A device constructed substantially as here in shown and described has been found effective, in use, to stop the machine and associated feeding mechanism when running at the usual high speed before the piece of goods has been carried more than a few inches beyond the point at which a failure to properly scope of the appended claims, without depart-.

ing from the spirit or sacrificing the advantages thereof.

What we claim as new, and desire to secure by Letters Patent, is

1. A stop device for use in connection with a power-driven sewing machine, comprising means adapted to be actuated by the machine and when so actuated to effect the shutting off of the power driving the machine and means normally bearing laterally against an edge of the piece of goods being sewed on the machine and controlled by the proper stitching thereof for controlling the said powercontrol means. p

2. A stop attachment for sewing machines, comprising a movably mounted member normally biased to a position to be acted upon by a movable part of the running machine and operative when acted upon thereby to effect the shutting off of the power driving the machine, and for the control thereof a member slidably mounted to bear against the edge of the hem of a piece of goods being sewed upon the machine to be held thereby and in turn to'hold said member out of operative position and operative on the failure of the machine to sew the hem to shift between the folds inoperative so long as the point of the detector is held at the edge of the hem and will be released to shut off the power when the point of the detector is shifted into the hem.

4%. In a device of the character described, the combination, with a power-driven sewing machine, of a movably mounted member adapted by a shift in its position to effect the shutting off of the power driving the ma chine, an elementmovably mounted upon said member and normally biased to position to be acted upon by a cam on the flywheel of the machine to shift the position of the member to shut off the power driving the machine, and means for controlling said element comprising a detector slidably mounted in position to bear against the edge of the hem of a piece of goods being sewed upon the machine and as held thereby to hold the element out of operative position and means adapted to shift the detector within the folds of the hem when not being properly sewed to thereby release the element.

5. In a device of the character described, the combination, with a power driven sewing machine, of a spring catch adapted to releasably lock in place a lever by which the sewing machine is operatively connected with a power shaft, a movably mounted member normally biased to a position to be actuated from the fly-wheel of the machine to withdraw the catch and release the lever, and means adapted to bear laterally against the edge of the hem of a piece of goods being hemmed on the machine and to hold said member out of operative position so long and only so long as the hem is being sewed.

CHARLES A. COUCH. SAMUEL P. HATCHER.

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