US1765342A

US1765342A - Presser foot and chain cutter for sewing machines

Info

Publication number: US1765342A
Application number: US315464A
Authority: US
Inventors: Lutz Friedrich
Original assignee: Union Special GmbH
Current assignee: Union Special GmbH
Priority date: 1928-06-29
Filing date: 1928-10-27
Publication date: 1930-06-17
Anticipated expiration: 1947-06-17

Description

F. LUTZ June,.1 7, 1930.

' Pnsss'n FooT AND CHAIN CUTTER Fon sEwINs MACHINES 2 Sheets-Sheet l Filed Oct. 27, 1928 l .hm17,1930.4 F, UTZ 1,765,342

PRESSER FOOT AND CHAIN CUTTER FOR SEWING MACHINES Filed Oct. 27, 1928 Zigeets-Sheet 2 25 the machine embodying Patented June 17, 1930 UNITED STATES PATENT OFFICE .f

FRIEDRICH LUTZ, F STUTTGART, GERMANY, ASSIGNOB T0 'UNION SPECIAL IASCHINENFAIBBIK, G. M. B. H., 0F STUTTGART, GERMANY PBESSEB FOOT AND CHAIN GUTTER FOB SEWING MACHINES Application October 27, 1928, Serial No. 815,464, andin Germany une 29, 1928.

Y The invention relates to newA and useful improvements ini presser foot for sewing machines, and 'a chain cutter which is associated therewith.

An object of the invention is to provide a presser foot with means cooperating with the feed and the throat plate for feeding and holding the enchained thread loops between the stitched articles. l A

1 A further object of the invention is to provide a presser foot and chain cutter of the above type wherein the presser foot is so constructed as to control and guide the chain and insure the feeding of the chain into the chain cutter. c

' A still further object of the invention is to provide a presser foot and chain cutter of the above type wherein the enchained loops are gripped and held while thesame are bef '5 ing severed.

- In the dra gs which show by way of ill lustration one embodiment of the invention:

Figure 1 is a view partly in -section and partly-in side elevation showing a portion of v the improvements;

Fig. 2 is a view part y in front elevation, and partl in vertical section of the parts shownin ig.1; i Fig. 3 is a'view partly in section and partly in` lan of the arts shown in Fig. 1; f

ig. 4' is a view showing more or less diagrammatically partly in plan and partly in section the arrangement of the throat plate, the presser foot members, and th cutter;

Fi 5 is a plan view ofthe throat plate showing the feed sections and also showing the enchained loops as positioned for severing;

Fig. 6 is a vertical view in section through the center of the presser foot showing the auxiliary section controllin the enchained thread loops, the feed section cooperating therewith, the throat plate and the severing cflerices at the tiii'ie when the chain is being Fi 7 is a view similar to Fig. 6 but showing t e parts positioned so that the `chain is clamped and is being severed by the 'cutting devices.; f

5 Fig. is a view partly in section and partly in side elevation showing the position of the 4parts as a section vf fabric enters beneath the front end of the foot.

The invention is directed broadly to a presser foot and chain cutter for sewing machines. The presser foot is constructed preferably with two sections which are independently mounted. These presser foot sections cooperate with the feed dog in the feeding of the material to the stitching mechanism. Located between the two sections is anv auxiliary presser foot which is mounted on one of the presser foot sections or on the machine frame so as to move independently of the foot sections. A s ring normally ldepresses the auxiliary section and yieldingly holds the auxiliarysection against the material or against the enchained threadvloops passing beneath thesame. Cooperating with this yieldin section is a section of the feed dog which eeds the enchained thread loopswhen there is no material beneath the auxiliary foot section. The throat plate and the auxilia section arev provided with toothed portions, which irmly grip the enchained thread loops and hold the same when the feed dog is on its idle movement. Associated with the presser foot is a chain cutter, which includes a stationary blade and a movable cutter blade which may be operated for severing the enchained thread loops held clamped between the auxiliary presser foot and the throat plate.

Referring more in detail to the drawings, the invention is shown as applied to a sewing machine which includes a throat plate 1 having

feed slots

2, 2 therethrough through which the

sections

3, 3 of the feed dog operate.

- Centrally of the throat plate is an opening 4; for the needle. 5 of the machine. yThe needle 5 is' carried by a needle bar 6, which reciprocates in the usual manner in an overhanging arm, a p oi'tion of which is indicated at 7 in the drawings.

The throat plate is provided with a slot 8 in rear of the needle opening in which a section 9 of the feed dog operates. At the rear end of the slot 8 there is a bridged portion 1'0 provided with teeth 'on its upper face. The

eed sections are all provided with teeth on i their upper face and the middle section 9 of the feed dog is rounded off at 11 so as to 4avoid cutting the chain. The material is held on the work support by two presser feet, one of which is indicated at 12 and the other at 13. The presser foot 12 is carried by a presserbar 14, and the presser foot 13'is carried by a presser bar 15. The presser foot 13 is pivotally secured to the presser bar by means of a pivot bolt 16. The presser foot 12 is pivotally secured to the presser bar 14 by a pivot bolt 17. This provides means whereby the sections of the presser foot can tilt on the presser bars when a section is laid underneath the presser feet. The presser foot 13 is the main presser foot of the machine and has a portion which extends around in front of the needle. The two presser feet are spaced from.

each other in the region in rear of the needle and this forms a guiding channel for the enchained thread loops causing said enchained thread loops as they feed away from the stitching point to move directly toward the rear of the machine. Located in this channel between the two presser feet is an auxiliary presser foot 18. The auxiliary presser foot 18 is rigidly connected to a supporting standard 19, which moves freely in a sleeve 20 carried preferably by the presser bar 15. Located within this sleeve is a spring 21'which normally presses the auxiliary presser foot downward toward the throat plate to yieldingly hold said foot against the fabric or enchained thread loops. This auxiliary section of the presser foot is provided with a toothed portion 22.

Associated with the presser foot is a chain cutter, which includes a stationary cutting blade 23 supported in any suitable way, and a movable cutting blade 24. The movable blade is mounted on a lever 25, pivoted at 26 t'o the bracket 27, which is secured by suitable screws 28, 28 to the resser bar 15. The sleeve 20 is also mounte on this bracket 27. This lever 25 may be operated in any desired way, but is preferably actuated by article Vcontrolled means for the severing of the enchained thread loops.

When a fabric to be stitched is passing beneath the presser feet both the presser feet and the auxiliary presser foot will be resting on top of the fabric and cooperate with the feeding sections of the feed dog to feed the materlal. After an article is stitched and passes from beneath the presser feet a series of enchained thread loops may be formed. The

auxiliary section of the presser foot will engage the enchained thread loops and cooperate with the central section of the feed dog to feed said'enchained thread loops. The enchained thread loops will lie in the channel between the two presser feet, and this will guide the enchained thread loops so as to direct them into the severing devices. When the auxiliary presser foot is pressing the enchained thread loops against the throat plate, the toothed section on the auxiliary foot and the toothed section on the throat plate will firmly grip and hold the enchained thread loops. The cuttin devices are immediately in rear of the auxillary section and the bridging portion of the throat plate which carries 'this toothed portion. Therefore, the cutter when operated will sever the enchained thread loops close to the point where they are gripped and this will hold the enchained thread loops and insure the proper severing of the same. When a fabric section'is started beneath the presser feet the presser feet will be tilted as shown in Fig. 8 of the drawings. At this time however the auxiliary presser foot will move down beneath the lower face of the presser feet and will engage the enchained thread loops and continue to feed the enchained thread loops until the fabric sec- 1 tion reaches the needle so that the threads are anchoredin the material, after which of The purpose of the improved presser foot is to uide and feed the enchained thread loops etween stitched articles, and to hold said enchained thread loops relative to the severing devices so that the enchained thread loops may be severed at will. The severing devices are located very near to the needle so that after-'the enchained'thread loops are severed there is avery short length of enchained thread loops. VVhile the fabric section is passing beneath the foot this auxiliary section of the presser feet will control and feed the enchained thread loops and prevent any skip ing of stitches until the fabric reaches t e needle so that the enchained thread loops are anchored therein.

It is obvious that minor changes in the details of construction may be made without departing from the spirit of the invention as set forth in the appended claims.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent, is

1. The combination of a presser foot having fabric engaging portions and a needle opening, said fabric engaging portions being spaced from each other in rear of the needle opening, an independently yielding auxiliary fabric and chain engaging portion located in said space, and a chain severing device located directly at the rearof said yielding section for severing the enchained thread loops.

2. The combination of a presser foot having fabric en aging portions and a needle opening, said abrio engaging portions being spaced from each other in rear of the needle portion logaging portions of the presser foot and having an independent feeding section cooperating with said auxiliary fabric engaging portion, and a chain severing device located directly at the rear of said yieldiiw section for severing the enchained thread oops.

3. The combination of "a presser foot having independently mounted fabric engaging portions one of which is provided with a needle opening, said fabric' engaging portions being spaced frein each other in the region in rear of the needl'e'gfor forming a -channel to guide the enchained thread loops during chaining between stitched articles, an independently yielding auxiliary section located in said space for engaging said enchained thread loops during chaining, afeed dog having feeding setieiis'coperating with the fabric engaging portions of the presser foot and havinga feeding section cooperating with said auxiliary fabric engaging por tion for feeding the enchained thread loops, and achaiii severing device disposed at the rear end of said aiixiliaryfabric engaging portion. Y

4. The combination of apresser foot having independently mounted fabric engaging portions one of which is provided with a needle opening, said fabric engaging por,- tioiis being spaced from each other in the region in rear of the needle for forming a channel to guide the'enchained thread loops during chaining between stitched articles, au independently yielding auxiliary section located in said space for engaging said enchained thread loops during chaining, a feed dog having feeding sections cooperating with the fabric engaging portions of the presser foot and having a feeding section cooperating with said auxiliary fabric engaging portion for feeding the enchained thread loops, a throat plate having a bridging portion in rear of said feeding section which cooperates with the auxiliary fabric engaging portion,

said bridging portion and said auxiliary fabric engaging portion having toothed cooperating surfaces' for gripping the enchained thread loops, and a severing device located directlyin rear of said bridging portion for4 severing the enchained thread loop while gripped between said throat plate and said auxiliary fabric engaging section.

5. The combination of a presser foot having fabric engaging portions pivotally supported so as to tilt in passing onto fabric sections, one of said sections having a needle opening therethrough, said sections being spaced in rear of the needle opening, an auxiliary fabric engaging portion located in said space, 'means for supporting the same whereby it may yieldiiigly move vertically independently of the presser foot fabric engaging portions, a throat plate having feed slot's and a bridging portion directly beneath the rear end of said auxiliary fabric engaging porported so as to tilt in passing onto fabric sections, one of said sections having a needle o eninc therethrough said sections bein spaced in rear of the needle opening, an auxiliary fabric engaging portion located inxsaid space, nieans for supporting the saine wherep'endently of the presser foot fabric engaging portions, a throat plate having feed slots and a bridging portion directly beneath the rear end of said auxiliary fabric engaging portion, a feed dog having feeding'sections cooperating Witli the presser foot and the auxiliary section, said auxiliary section and said bridging poi-tion having teeth for engaging and firmly clamping the enchained thread loops for holding the saine while they are being severed, a chain severing device including a lower stationary blade and an up-y per niovable blade operating 1n a plane at right angles to the line of feed for severing the enchained thread loops, said severing devices being located directlyin rear of said auxiliary section. f

In testimony whereof, I affix niy signature.

FRIEDRICH -LUTZ.

bv it may yieldingly move vertically indelill)