US2802436A

US2802436A - Thread positioning means for button sewing machines

Info

Publication number: US2802436A
Application number: US498545A
Authority: US
Inventors: John H Jackson
Original assignee: AMF Inc
Current assignee: AMF Inc
Priority date: 1954-01-13
Filing date: 1955-04-01
Publication date: 1957-08-13
Anticipated expiration: 1974-08-13
Also published as: US2811939A; US2783897A; GB781321A

Description

Aug. 13, 1957 J. H. JACKSON THREAD POSITIONING MEANS FOR BUTTON SEWING MACHINES Original Filed Jan. 13, 1954 FIG. 3

.INVENTOR JOl-N H. JACKSON BY 4 A oazsv Patented Aug. 13, 1957 THREAD POSITIONING MEANS FOR BUTTON SEWING MACHINES John H. Jackson, Brooklyn, N. Y., assignor to American Machine & Foundry Company, a corporation of New Jersey Original application January 13, 1954, Serial No. 403,678, Divided and this application April 1, 1955, Serial No. 498,545

6 Claims. 01. 112-110 This invention relates to a sewing machine and more particularly to a thread positioning means adapted to receive a length of thread, position it properly and make it substantially impossible for this length of thread to get out of position where it might be spitted by the needle or broken by operating parts of the machine.

This application constitutes a division of application Ser. No. 403,678, filed by Arthur G. Mirel on January 13, 1954, for Button Sewing Machines.

The present invention consists in providing a sewing machine, such as disclosed in Johnson et al. Patent No. 2,451,495, and in copending Patterson and McGinley application S. N. 217,645, now Patent No. 2,739,550, dated March 27, 1956, with a thread trap and a thread lock adapted to function during operation of the machine in always maintaining the thread properly disposed with respect to the needle and operating parts which come in contact with the thread so that breakage of the thread is substantially eliminated.

While reference is made to the above referred to Johnson et al. patent and Patterson et al. application, it is understood that the invention is not limited in use solely to the type of the machine disclosed insuch patent and said application.

According to the form of the invention illustrated herein, the loose end of the thread which is pulled through the work, in a sewing machine provided with opposed upper and lower alternately operating needle bars adapted to pass a needle back and forth through the work, is provided with a thread trap located adjacent the upper position of the lower needle bar such that when the thread puller pulls the loose end of the thread through the work, this end of the thread is disposed on a support forming a part of the thread trap.

The thread which is used in a button sewing machine of the type disclosed in the patent and application above referred to and copending application S. N. 403,678 is cut in lengths from a spool of thread. -It has been'found that the' lengthof thread has a tendency to coil. in conformity v with the coiling of the thread'onthe spool from which it iscut. Thus" the thread tends to move out of the position where it can be moved into the thread trap, and out of the path of the movement of a thread lifter which is provided to dispose it in the thread trap.

In order to insure that the thread will be properly located in the thread trap, there is mounted on the support a spring-urged locking finger having a bar portion adapted to be engaged by the end of the thread lifter. When the thread lifter is located in its inoperative position, the end of the thread lifter engages the bar portion of the finger and holds it against the tension of the spring out of closing position with respect to an opening in the thread trap through which the thread is moved by the thread puller.

As the thread lifter moves into engagement with the thread on the support, the thread locking finger moves 700, it is also laid across a hook-shaped lifter finger 702 forwardly under the action of its operating spring to close the opening above referred to thereby making it impossible for the thread to twist or move out of the thread trap. It will be seen therefore that the thread when thus disposed is positively locked in the thread trap against removal therefrom.

It is an object of the invention to provide a novel thread trap and means for disposing and locking a length of thread in said trap against inadvertent or unwanted removal during the operation of a sewing machine.

It is a further object of the invention to provide a novel thread controlling mechanism for a sewing machine wherein a length of thread is positively controlled and prevented from unwanted lateral displacement out of a thread trap during the operation of the sewing machine.

With these and other objects not specifically mentioned in view, the invention consists of certain combinations and constructions which will be described fully hereinafter, and then set forth in the claims hereunto appended.

In the accompanying drawings which form a part of this specification and which like characters of reference shall indicate some or like part;

Figures 1 and 2 are isometric views illustrating the successive positions of a thread control mechanism embodying the invention, during the operation of the machine; and

Figure 3 is a partial plan view of some of the elements shown in Figures 1 .and 2.

Referring to the drawings which show a preferred embodiment of the invention selected for purposes of illustration, the sewing machine with which the invention associates and which forms a part, is provided with a thread receiving drum 700 on which the loose end of a length of thread is adapted to be disposed by means of a'thread puller 168 during alternate operations of the upper and

lower needle bars

58 and 60.

The construction and operation of the machine with which the present invention is readily adaptable for use is similar to the type disclosed in Johnson et al. Patent Number 2,451,495. Such machine is provided with an upper needle bar 58 and a lower needle bar 60 and a thread disposing drum or surface or groove 700 on which the loose end of a thread of diminishable length is adapted to be laid by thread puller 168 during alternate movements of the needle bars, when the machine is in operation. Since the specific structure for

operating needle bars

58 and 60, and finger 702 do not form a specific part of the invention, and such mechanism is fully shown in the patents and applications above referred to, further showing and description are omitted as being unnecessary to a full understanding of the invention.

In order to prevent entanglement of the loose end of the thread with thread puller 168, or possible spitting by needle 142, the machine is provided with a thread control mechanism, which is illustrated in Figures 1 and 2 of the drawings. As the loose end L of the thread T is laid by the thread puller 168 onto thread trough or drum which is located in front of thread trough 700 and which is secured to an operating arm (not shown) pivotally mounted on a stud (not shown) on main base 50. The

free end of the operating arm carries a cam follower is moved upwardly as well as rearwardly, causing that portion of the thread which passes through the material to engage with a stationary thread guide lug 712, and a suitablyshaped trap 714, attached to block 716, pref- 3. erabl'y formed integrally with a member 708 secured to main base 50; In order to guide the thread into trap 714 and prevent it from slipping out of the same, a suitably shaped lock finger 720 works in. conjunction with and.

follows the lifter. finger 702 as soon. as the latter startsto move backward...

Lock finger 720 is mounted on a stud shaft 722 which.

is loosely supported in thelower portion of trap. 714. Lock finger 720. is .also provided with plate. or lug .724,

the. top edge of which is in engagement .with the lower:

front edg'efof lifter finger 702 whichholds lock finger. 720 in uprightposition asilong as finger 702 is inaits foremost position. As. soon as thewlatter moves rear- Wardly, I a suitable. tension. spring. 7'26. urges lock. finger. 7203rearwardly until.the:top edge of. plate 724-.engagese the frontedgeof. the. lowerportionof the trap.,714 and. thejtrap is: closed. Thus the-trapped lengthxof.thread.

cannot move or twist laterally out of trap 714.

Whatl claimis:

l. Ina. sewing machine of the type described having. an upper needle bar. and a lower. needle. bar adapted to.

passa needle andathreadback. and forth through work to be stitched, a thread receiving surface located adjacent said lower needle.-bar,.a member having. aanarrow thread supporting ledge located adjacent said. lower needle bar. and above. said. surface, a thread puller for pulling the loose end of said thread. through said work and. disposing it .uponsaid. surface, a thread trap located.

adjacent said ledge, a device located adjacent said'ledge. for movingsaid loose-endof saidthread disposed on said surface to position said threadifor delivery into said trap in response to the upward movement of said upper needle bar, said upward movement of. said upper needle bar also locating. said; thread on said ledge, and. a thread lock. member positioned. adjacent said trap adapted. to

move towards said thread trap to lock said. thread against movement away from said thread trap.

2. The invention definedin claim 1 wherein: said thread.

lock member comprises an arm, meanspivotally mounting said. arm on said thread trap. for movement to and from said thread trap, meansnormally tending to urge said.

armtowardslocking engagement :with said: threadvtrap,

and means on said arm engaged by said device, prior to the operation. of said device, for maintaining said arm outof threadlockingrelationship with said' thread trap..

3...In a sewingmachine. of the; typehaving a' work support. table, an upper needle bar and a lower, needle bar. adapted to pass aneedleand a thread back and'forth through work to be stitched, a thread receiving surface mounted adjacent said. lower needle bar having, aleading and. atrailing end, a; member'- having a thread supporting. ledge. positioned. adjacentsaid. surface longitudinally. spaced from said leading end of said surface,

means mounting said member at one side of said lower:

needle. bar, a thread puller forpulling the loose end of said thread through saidwork and disposing'it. upon said. surface, a thread trap located adjacent said leading 4. In a sewing machine of the type havinga-work.

support table, an-upper needle 'bar and at lowerneedle bar adapted to pass a needle and a thread back: and forth through work to be stitched, a thread receiving surface having a portion located adjacent said lower needle bar, and a threadpull'er forpulling the looserend of said thread through said work and disposing it upon said surface, a membermounted above-said surface having a thread supporting ledge, a thread trap located adjacent said ledgeandsubstantially alignedtherezwtth, ardevice mounted. for movement: above; said; surface; for. moving said loose endof said thread; disposed'torn saidldrum to' position. said; thread; for. delivery :into: said' trap. and on. said. ledge in :response: to; th'ewupwardzmovernenti of I said" upper needle bar, a-threadi lockmembertpositi'oned above said. surface andadjacent said'lower needle bar,1 and meansoperative in response" to the movement ofsaid device to dispose saidl thread :on. said; surfacefor moving said lock. member: into operativesrelationship withsaid thread lock.

5: In a. sewing;gmachine of the; type having. a; work support table; an;upper needle-.bar. and'a lower needle bar adapted to; pass: a needle: and; a: thread back and forth through; work. to be: stitched, ..a.thread receiving:

surface-mounted. adjacentsaid'; lower: needle: bar, and: a

thread puller; for pulling. the loosezend of said. thread through said work and: disposing-it: upon :said: surface; .athread trap locatedadjacent saiddoWen-needle; bar"and along the path of travel oftsaid'thread pullena'devic'e movably: mounted above A said surface." for: moving: said loose end of. said: thread: disposed; on; saidi surface: to posit-ion. said thread 'for delivery; into-said lZIKPJiDJ'IESP'OHSfi to the upward movement of said upper needlerbar, and

a thread. lock-member mounted-above; said surface: and operative in response 'to' the. amovementrofisaid device. to move. towards said thready trap: and. lock said thread against movement. away;.fromr.sairt thread trap;

.6. Therinventionzdefinedin claim 5; including a thread 7 disposing-finger carriech byrsaidihreadipuller; and means-- for mountingnsaidi finger on said: thread puller so' as to disppserthe. loose end of the thread :pulleibyraid thread puller properly: on; said .thread receiving; surface.

References. Cited inlthei. file of thispatent: UNITEDJS'FATES PATENTS? 1,369.,371' Allen Feb... 22,} 1921 2,210,638 Spaine et al. Aug. 6; 1940' 2,250,973" Spaine etial. July 29; 1941- 2,301,798"

Sp'aine et.'al Nov. 10, I942