US3924554A

US3924554A - Thread chain cutting apparatus

Info

Publication number: US3924554A
Application number: US520756A
Authority: US
Inventors: Donald Cummins
Original assignee: AMF Inc
Current assignee: Automated Machinery Systems Inc
Priority date: 1974-11-18
Filing date: 1974-11-18
Publication date: 1975-12-09
Anticipated expiration: 1992-12-09
Also published as: DE2548498A1; IT1052256B

Abstract

An apparatus for severing thread chain loops linking sections of arms one to another. The invention employs a rotating wheel having convoluted slots cut therein, and a pair of knives disposed near the wheel. As the thread passes through a channel, it is engaged by one of the slots of the wheel and drawn inwardly of the apparatus. Subsequently, the chain is further drawn over a pair of barriers each of which is to one side of the wheel and act to maintain the thread taught. Subsequently, the thread chain is caused to bear upon the cutting edge of the knives and severing takes place.

Description

United States Patent [191 Cummins [451 Dec. 9, 1975 THREAD CHAIN CUTTING APPARATUS [75] Inventor: Donald Cummins, Hopewell, Va.

[73] Assignee: AMF Incorporated, White Plains,

22 Filed: Nov. 18,1974

21 Appl. No.: 520,756

[52] US. Cl. 112/252 [51] Int. Cl. DOSB 65/04; DO5B 65/06 [58] Field of Search 112/252, 130, 122, 129, 112/2525, 79.5

[56] References Cited UNITED STATES PATENTS 2,828,702 4/1958 Hall 112/79.5

2,977,906 4/1961 Follender 112/795 3,025,811 3/1962 Kostenowczyk 112/2525 3,490,397 l/l97O Klassert 112/795 FOREIGN PATENTS OR APPLICATIONS 11/1929 Germany 112/2525 Primary Examiner-H. Hampton Hunter Attorney, Agent, or FirmGeorge W. Price; Martin Smolowitz [57] ABSTRACT An apparatus for severing thread chain loops linking sections of arms one to another. The invention employs a rotating wheel having convoluted slots cut therein, and a pair of knives disposed near the wheel. As the thread passes through a channel, it is engaged by one of the slots of the wheel and drawn inwardly of the apparatus. Subsequently, the chain is further drawn over a pair of barriers each of which is to one side of the wheel and act to maintain the thread taught. Subsequently, the thread chain is caused to bear upon the cutting edge of the knives and severing takes place.

9 Claims, 8 Drawing Figures US. Patent Dec. 9 1975 shw 1 of 3 3,924,554

I LLILILU FIG. I

FIG. 2

U.S. Patent Dec. 9 1975 Sheet 2 of3 3,924,554

US. Patent Dec. 9 1975 Sheet 3 of3 3,924,554

THREAD CHAIN CUTTING APPARATUS The present invention is directed to an apparatus for severing a chain thread serving to allow a plurality of garments or garment sections to be linked to one another. More particularly, the present invention relates to an automatic arrangement employing a pair of stationary knives adapted to sever chain threads from their associated garment or garment sections as they are being processed.

In the mass production of garments and in particular where such garments are being rendered upon by automatic or semi-automatic machines which perform a number of operations, such as, for an example, the sewing and subsequent pressing of trouser legs, sleeves, etc., it is most common to employ a chain thread of approximately 1 to 2 inches in length which serves the purpose of maintaining a constant flow of material through the operating machinery. The details call for an operation where the chain thread joining one garment or garment parts to the next is caused to urge the continuous advance of such garments through the machine by a combination of a pulling action, as well as, gravity feeding. However, there does arrive a point in the overall operation where it is desirable to sever such chain threads so as to separate the various garments or garment parts. Up until the present time, this operation has traditionally been carried out by an individual whose sole activity has been to sever such thread chains by manual operation. With labor representing an expensive cost factor, industry has sought means and ways to decrease such additional labor for carrying out this operation, etc. Furthermore, from time to time, it is desirable to sever such chain threads at select intervals, as for an example, sever every other chain thread, while at the same time maintaining other chains, i.e. retaining like pairs of trouser legs or sleeves, etc.

Obviously, it would be most advantageous to arrive at a means for'selectively severing such chain threads without the need for manual labor.

In addition, it has been found that the severing of the chains in terms of operational sequence, ties in with certain sewing and pressing operations, as for an example, carried out in an automatic manner more clearly detailed, for example, in US. Pat. Nos. 3,372,497; 3,478,451; 3,659,537. In such instances, it is most desirable to control the chain thread cutting operation in concert with the aforementioned sewing and pressing operation.

The principal features of the present invention are directed to an apparatus for severing thread chains attached to a series of garment members in a predefined fashion after conveying such garment sections to said device; a housing structure for retaining said apparatus, guide means integral with said housing, for receiving said thread chain through passage ways associated therewith; a wheel disposed away from said guide means, driven by motor means affixed to said housing, said wheel being adapted to engage and move a defined section of thread chain away from the point of entry at said guide means; barrier means proximate to said rotating wheel and being spaced therefrom, serving to provide support for said thread chain during its movement away from said guide means by said rotating wheel; a pair of fixed knives each of which being disposed on either side of said rotating wheel for a blade to blade distance representing the amount of chain thread to be cut, said knives being adapted to sever said thread chain at a predefined time in response to the distance traveled by said chain as it travels under the action of said rotating wheel; and spring loaded sheaths covering the cutting surface of said knives serving to prevent such surfaces from prematurely cutting the thread chain until the downward force applied by the chain on said sheaths exceeds the opposing spring load force, at which time the cutting surface of said blades severs the thread chain.

Also within the scope of the present invention is a rotating wheel provided with a series of spaced convoluted slots each of which is of a sufficient width to accept a thread chain passing therethrough and moving in accordance with the curvature of such slot during the rotation of said wheel. Furthermore, the invention includes a structure where said wheel is in proximity to a pair of substantially flat blocks adapted to serve as thread supporting surfaces adapted to cause the chain thread to become taught as it is being advanced through said slot of said rotating wheel, thereby enabling the force generated on said sheaths to overcome the spring bias of said sheaths and allow said knives to act upon said thread chain.

Accordingly, it is the main object of the present invention to overcome the defects of the prior art.

It is still another object of the present invention to provide an efficient chain thread cutter capable of being employed in a garment manufacturing operation which will eliminate the need for separate manual labor for cutting such chains.

Still a further object of the present invention is to provide an apparatus capable of cutting chain threads while simultaneously increasing the rate of overall production.

A further object of the present invention is to provide a device for use with an automatic sewing-pressing apparatus capable of being programmed to selectively sever thread chains in a prescribed manner.

Other objects and advantages attendant to the present invention will be more clearly understood with repsect to the specification and drawings as defined by the claims set forth hereinbelow.

IN THE DRAWINGS FIG. 1 is a rear view of the invention showing the thread engaging wheel.

FIG. 2 is a front view of the invention shown in FIG. 1.

FIG. 3 is a partial profile view showing the flow of chained material prior to and after entering the inventive device.

FIG. 4a is a pictorial view of the wheel and thread chain engaged therewith at the outset of the cutting cycle.

FIG. 4b is another view of the chain and wheel at a point in time subsequent to that illustrated in FIG. 4a.

FIG. 5a is a partial cross-sectional view of FIG. 4a. FIG. 5b is a partial cross-sectional view of FIG. 4b.

FIG. 6 is a pictorial representation of the thread chain exhaust system.

The present invention as is generally shown in FIGS. 1-6 contemplates a device for automatically removing the thread chain T from between work pieces of limp material W that are being sewn together as such joined pieces flow from the dewing machine station. More particularly, the present invention employs a mechanical arrangement for guiding, engaging and cutting the 3 thread chains (see FIG. 3).

As the various work pieces W exit from the sewing machine or from a stitching station, they are connected one to another and are held in continuity with respect to one another by means of a thread T in the form of a woven chain. Such work pieces advance onto the next station by means of a conveyor or skid plate 1. At that point in the flow of operations, the present invention 2 serves to sever the thread chain (see FIGS. a5b) particularly, as shown in FIG. 3 the series of connected work pieces W is caused to drop over a nose bar arrangement 3 where a thread cutter is located. In the most simplist terms, the present invention employs a series of adjacent parallel barriers (in the form of a grill work) 4 spaced apart from one another which enable the sewn pieces W to be drawn in proximity to the knives 5 as the thread chain T enter the grill 4. In effect, such plurality of barriers 4 permits the-chain T to pass through for subsequent treatmentinterior of the grill work 4. The sewn work pieces W, however, are

kept away from any undesirable cutting action during the thread chain severing operation. Asthe workpieces W are crossing over anose bar of conveyor 1 the thread chain T passes through the grill work 4 and is engaged by a rotating pick-up wheel 6 whose plane is perpendicular to the work piece flow. The rotating wheel 6 is provided with a series of convoluted cuts 7 which serve to provide a corresponding number of simularly shaped slots oriented toward the interior or center of the wheel 6. Furthermore, the comers 13 of each slot are dressed so as to permit positive entrance of the chain T into the respective slots 7."

As the thread chain T enters such curved slots 7 (for an example, (see FIGS. 4a-4b) there may exist four such slots 7 cut into a given wheel) being offset by 90 with respect to one another, .it is drawn inwardly (FIG. 5b) and over a pair of gripping blocks 8 situated on either sides of the wheel 6. The blocks 8 are so disposed so as to allow the chain T to be drawn into the wheel slot 7 over the blocks 8, while simultaneously drawing or pulling the sewn pieces W to the grill face 4. Thus, there is provided a positive gripping action on the thread chain T. It has been found that the clearance distance between the gripping blocks 8 and the rotating wheel 6 may be a few thousanth of an inch, i.e., 0.004 inches, thus providing positive gripping action on the chain T.

The actual cutting knives 5 are stationary and disposed on either side of the rotary wheel 6. Each knife 5 is located beneath the grill 4 and has associated therewith a spring loaded sheath 9 (see FIGS. 5a-5b). The engagement of the thread T chain by the wheel 6 as it rotates, causes the chain T to become taught and has its relative position fixed with respect to the grill 4 and the knives 5, by virtue of the action of the respective gripping blocks 9. In operation, the sewn pieces W are drawn to the grill face 4 and the knife sheaths 9 are forward of the knife cutting edges so as to prevent premature cutting. Thereafter, the sewn pieces W are caused to meet the grill face 4 due to the continuous rotation of the wheel 6 and drawing of the thread chain T. The

sheaths 9 on the knives 5 are starting to expose the In effect, the sewn pieces W by being forced to meet the grill face 4 via rotation of the wheel 6 which has engaged the thread chain T, increases pressure on the spring loaded sheaths 9 and .in turn causes them to move toward the rear of the cutting edges of the knives 5 and in turn severing is effectuated. The knives 5 on either, side of the pick-up wheel 6 have edges that are parallel to the plane of the wheel 6. The increase in pressure on the spring loaded sheaths 9 is attributable to the thread chains T being drawn further and further into the gripping blocks 8 by the rotation of the wheel 6. During the cutting operation, the necessary force to overcome the opposing spring force of the sheaths 9 is such, so as to cause the sheaths 9 to retract and allow the thread chain T to be severed at both ends, at a nominal distance from the work pieces W which are attached to one another through the thread chain T.

After the thread chain is severed, it is caused to be pulled through the gripping blocks- 8 and hang freely in the rotating wheel 6, (see FIG. 6). Then as the pick-up wheel 6 continues to rotate, the severed thread chain T is removed by a small blast of air via conduit 10 which causes theloose chain T to be blown freely of the channel 1 1 formed bya space between the wheel 6 and its associated cover 12. I I

The aforementioned operation is intended to be fully automatic and continuously takes placefor" as long as is required with thread chains being continuously severed and air blasts causing the severed chains to be blown freely at all times.

The device of the present invention is a purely mechanical device easy to maintain and relatively trouble free. The interaction betweenthe convoluted slots 7 in the wheel 6 and the gripper blocks8 on either sides of the wheel 6 is quite essential for correct cutting action by the stationary knives 5. This follows for the reason that too little pressure generated by the action of the rotating wheel 6 and the gripper blocks 8 on the thread chain T will fail to produce the necessary force required to overcome the resistance offered by the spring loaded sheaths 9 to exposethe cuttingsu rfaces of the knives. On the other hand, too muchpressure and resultant force on the sheaths 9 can cause the knife blades to be exposed prematurely and cut the thread chain T at a point along its length which is "undesirable, particularly with respect to excessive residual thread portion left on the sewn pieces.

Likewise, the knives 5 must be positioned both with respect to the grill 4 and with respect to the working edges of the gripping blocks 8 so as to insure a positive and clean cut of the thread chain T at a given point along such chain.

" These spatial relationships must, in turn, be related to the speed of travel of the linked sewn garments W and the speed of rotation of the moving wheel 6. Failure to relate these two conditions to one another can cause undesirable operating conditions and incorrect severing of the threadchain T.

Though, the present invention has been described with respect to a specific embodiment, it is to be understood that such terminology vis not intended to be restricted or [confining and that various modifications of detail may be resorted to without departing from the spirit and scope of the present invention.

I claim:

1. An apparatus for severing thread chains attached to a series of garment members is a predefined fashion after conveying su'ch garment sections to said device; a

housing structure for retaining said apparatus, guide means integral. with said housing, for receiving said thread chain through passage ways associated therewith; a wheel disposed away from said guide means, driven by motor means affixed to said housing, said wheel including means to engage and move a defined section of thread chain away from the point of entry at said guide means; barrier means proximate to said rotating wheel and being spaced therefrom, serving to provide support for said thread chain during its movement away from said guide means by said rotating wheel; a pair of fixed knives each of which being disposed on either side of said rotating wheel for a blade to blade distance representing the amount of chain thread to be cut, said knives being adapted to sever said thread chain at a predefined time in response to the distance traveled by said chain and the force resulting therefrom as it travels under the action of said rotating wheel; and spring loaded sheaths covering the cutting surface of said knives serving to prevent such surfaces from prematurely cutting the thread chain until the downward force applied by the chain on said sheaths exceeds the opposing spring load force, at which time "the cutting surface of said blades severs the thread chain.

2. An apparatus as claimed in claim 1 wherein: the means on said rotating wheel is a series of slots cut therein and being spaced apart from one another and each of which tending to radiate outwardly from the diametrical center of said wheel.

3. An apparatus as claimed in claim 1 wherein: said rotating wheel is provided with a series of spaced con- 6 voluted slots each of which is of a sufficient width to accept a thread chain passing therethrough and moving in accordance with the curvature of such slot during the rotation of said wheel. V

4. An apparatus as claimed in claim 1 wherein: said guide means includes a plurality of spaced apart parallel slots serving to provide initial entry of the thread chain into said apparatus for engagement with a given slot in said rotating wheel.

5. An apparatus as claimed in claim 1 wherein: said wheel is in proximity to a pair of substantially flat blocks adapted to serve as thread supporting surfaces adapted to cause the chain thread to become taught as it is being advanced through said slot of said rotating wheel, thereby enabling the force generated on said sheaths to overcome the spring bias of said sheaths and allow said knives to act upon said thread chain.

6. An apparatus as claimed in claim 1, wherein: means are provided for purging the device of thread chain sections which have been severed.

7. An apparatus as claimed in claim 1, wherein: each of said convoluted slots is offset by with respect to one another.

8. An apparatus as claimed in claim 1, wherein: a clearance distance between said rotating wheel and said flat blocks is 0.004 inches.

9. An apparatus as claimed in claim 1, wherein: said cutting knives are disposed with respect to said guide means and said blocks to thusly insure positive cutting of said thread chain at a preselected point along its length.

Claims

1. An apparatus for severing thread chains attached to a series of garment members is a predefined fashion after conveying such garment sections to said device; a housing structure for retaining said apparatus, guide means integral with said housing, for receiving said thread chain through passage ways associated therewith; a wheel disposed away from said guide means, driven by motor means affixed to said housing, said wheel including means to engage and move a defined section of thread chain away from the point of entry at said guide means; barrier means proximate to said rotating wheel and being spaced therefrom, serving to provide support for said thread chain during its movement away from said guide means by said rotating wheel; a pair of fixed knives each of which being disposed on either side of said rotating wheel for a blade to blade distance representing the amount of chain thread to be cut, said knives being adapted to sever said thread chain at a predefined time in response to the distance traveled by said chain and the force resulting therefrom as it travels under the action of said roTating wheel; and spring loaded sheaths covering the cutting surface of said knives serving to prevent such surfaces from prematurely cutting the thread chain until the downward force applied by the chain on said sheaths exceeds the opposing spring load force, at which time the cutting surface of said blades severs the thread chain.

3. An apparatus as claimed in claim 1 wherein: said rotating wheel is provided with a series of spaced convoluted slots each of which is of a sufficient width to accept a thread chain passing therethrough and moving in accordance with the curvature of such slot during the rotation of said wheel.

7. An apparatus as claimed in claim 1, wherein: each of said convoluted slots is offset by 90* with respect to one another.