US2370738A

US2370738A - Sewing machine

Info

Publication number: US2370738A
Application number: US388924A
Authority: US
Inventors: Frank A Kucera
Original assignee: Union Special Machine Co
Current assignee: Union Special Machine Co
Priority date: 1941-04-17
Filing date: 1941-04-17
Publication date: 1945-03-06
Anticipated expiration: 1962-03-06

Description

March 6, 1945. F. A. KUCERA sEwiNe MACHINE Filed April 17, 1941 4 Sheets-Sheet 1 ll Illl S mm Q mm NM 5 v :VE

INVENTOR FRAW/r 4. lfUGEfiA BY ATTORNEY March 6, 1945. F. A. KUCERA' SEWING MACHINE 4 Sheets-Sheet 2 Filed April 17, 1941 is I March 6, 1945. F. A. KUCERA 2,370,738

SEWING MACHINE Filed April 17, 1941 4 Sheets-Sheet 3 Il Illll k: C? ATToRflEY7- March 6, 1945. F; A. KUCERA SEWING MACHINE 4 Sheets-Sheet 4 Filed April 17, 1941 INVENTOR FRANK A-KUCE/PA S w H ATTORNEY Patented Mar. 6, 1945 sawma momma Frank A. Kucera, Chicago, 111., assignor to Union Special Machine Company, Chicago, 111., a. corporation of Illinois Application April 1'1, 1941, Serial No. 888,924 16 Claims. (01. 112- 235) This invention relates to sewing machines and more particularly to the improved construction and mounting of the presser foot employed in such machines and its novel relation to the worksupport and the work-feeding devices.

An object of the invention has been to provide a presser foot capable of effectively urging the work against the supporting and feeding means under a wide variety of conditions. In the sewing of garments of various sorts, and particularly those, such as overalls, formed of relatively heavy material, a problem is involved in insuring the regular and proper feeding of the material in relation to the needles and other stitch-forming devices. In forming seams, and particularly double-lap, felled seams, in various garments, such as overalls, in which the seams at points may cross other similar seams or special pocket formations or the like, a wide variation may be encountered in the number of layers of material to be dealt with by different portions of the feed dog, throat plate and presser foot. In machines specially designed for the production of double-lap, felled seams; such as those disclosed in the Thompson Patents Nos. 1,988,399 and 1,988,400, granted January 15, 1935, each side of the presser foot and the corresponding side of the feed dog will normally cooperate with only single layers of fabric while the intermediate portions of the presser foot and feed dog will be spaced sufficiently to allow the free passage of the four layers of material forming the seam. By the constructions disclosed in the Thompson patents, proper feeding of both of the felled and lapped pieces of material being stitched together is insured and in accordance with the second of these patents the main part of each section of fabric lies flat and is permitted to extend laterally without bending from the upper or lower surface of the seam. Similar provision is preferably made in accordance with the present invention.

However, in the prior constructions mentioned,

difficulty is encountered if a greater number of layers or thicknesses of fabric is presented at one side of the presser foot than the other. In such a case the feeding action will take place at only one side of the seam and the desired uniform feeding of both sections of fabric will be interfered with.

An important feature of the present invention is the mounting of the presser foot upon the lower end of the presser bar in such a way that the presser foot is permitted to accommodate itself readily for efiective cooperation with both sectwo sides.

tions of fabric being united along a seam, whether but a single layer or a plurality of two, three, four or more layers of material may be brought between the presser foot and the cooperating portion of the feed dog at either side of the seam. Toward this end, provision is made for the rocking of the presser foot freely in a direction transverse to the length of the seam being formed. Thus, either side of the presser foot may be raised or lowered in relation to the other side as different thicknesses of material are presented to the At the same time provision is made for the rocking of the presser foot in the direction of the length of the seam being formed so that it may accommodate itself readily to the different thicknesses of material encountered in crossingover transversely extending seams. To accomplish these results, the presser foot is so mounted on the head'of the machine, and preferably at the lower end of a presser bar, as to be capable of universal movement or adjustment with respect to the latter.

A further feature of the invention is the formation ofthe ,presser foot in a plurality of. sections arranged in tandem, all of the sections partaking of the universal adjustment motion mentioned and the sections themselves being independently adjustable in relation to each other. 7

Still another feature of the invention is the provision in a presser foot, particularly of the type adapted for cooperation with a double-lap, felled scam, in the manner explained, of an adjustable element or member arranged to cooperate with the lapped seam. The adjustment of this member may be conveniently and quickly effected so that the member may be readily set in a selected position for proper cooperation with the seam, depending upon the character of the work being dealt with. Through the adjustment of this member, more effective action of the presser foot is insured under all conditions of operation. The member may, for example, be set in one position when materials of a certain thickness are being dealt with and it may be set in another position when either thicker'or thinner materials are being handled.

A primary object of the invention has been to provide a presser foot having one or more of the features and advantages set forth above and tion will appear from a detailed description of an illustrative form of the same which will now be given in conjunction, with the accompanying drawings. in which:

Fig. I is a side elevation of a portionof a sewing machine embodying the invention, a portion of the work being handled also being shown.

Fig. I! is a top plan view of the improved presser foot shown in relation to a double-lap seam feller and a typical item of work, the presser bar to which the presser foot is attached being shown in section.

' Fig. III isa view partly in end elevation and partly in section, the presser foot and associated mechanism being shown in elevation and the :ork support and the work being shown in sec- Fig. IV is a side elevation of the complete presser foot shown detached from the machine.

Fig. Via a bottom view of the presser foot.

Pig. V1 is a transverse section through the presser foot taken along the line VI-VI :of Fig. IV.

Pig. VII is a side elevation of the presser foot shank.

Fig. VIII is a longitudiual, sectional view through the second or rear section of the presser foot, taken along the line VIII-VIII of Fig. V.

Fig. 1x is a transverse sectional view through said section of the presser foot, taken along the line IX-IX of P18. V.

Pig. 1: is a perspective view of an adjustable member forming part of the rear section of the presser foot, and

Figs. XI and xrr are transverse sectional views through the rear section of the presser foot, showing the presser foot in relation to the work feeding and supporting means when different portions of the work are brought into cooperation with these parts.

Referring now to the drawings, the invention has been illustrated in-connection with a feedofl-the-arm type of machine but it will be understood that it is adapted for use in connection with flat-bed machines as well. The machine may, in general, be of any appropriate construcin Fig. III, the feed dog is preferably of the type having different portions of its work engaging teeth l2 and ii at different elevations. This, as disclosed in the Thompson Patent No. 1,988,400, is for the purpose of normally enabling the two sections of fabric, joined by a doublelap, felled seam, to extend laterally from the top and bottom surfaces of the seam without a bend. The portion ll of the teeth of the feed dog, provided along one side of the latter, extends upwardly above the main portion 12 of the teeth a distance substantially equal to the thickness of three layers of the material to be sewn together. As will be understood, the feed dog has its toothed portions projecting upwardly through openings or slots provided in a throat plate II, which permits the desired vertical and horizontal movements of the feed dog.

Above the work supporting arm ll there is prO- vided a head I! in which there is slidably mounted, adjacent its forward end, a needle bar It adapted to carry and reciprocate one or more needles ll (three being shown). Any suitable means may be provided for reciprocating the needle bar, such as that disclosed in said ,Ghristensen et al. patent. It will be understood that one or more loopers will be provided in the work support arm It to complete the stitch-forming mechanism. These loopers (not shown) may be constructed and operated in the manner disclosed in said Christensen et al. patent.

- ,Also mounted in the'head I i, for vertical reciprocation therein, is a presser bar I! which is normally urged downwardly toward the. work supporting am It by means of a spring shown conventionally at 18c. Suitable manual means (not shown) may also be rovided for lifting the presser bar, whenever desired, in a manner well known. At the lower end of the presser bar, there is secured a shank it having a: socket 20 to receive the end of the presser bar. The shank is preferably of split construction and adapted to be clamped to the lower end of the presser bar by tightening a screw 21. The lower end of the shank is forked to provide a pair of spaced

walls

22 and 22 adapted to receive between them a long pin 24. Above the pin 24 and substantially midway between the ends thereof the yoke is provided with a cylindrical opening 25, at right angles to -the pin 24 and partially intersecting the passage formed between the

walls

22 and 23. In the opening 25 is inserted a pin 26 which is adapted to bear upon the upper surface of the pin 24. Directly beneath the pin 24 and in vertical alignment with the pin 28 is a smaller retaining pin 21 carried by the

walls

22 and 23. This construction is such that the pin 24 may rock freely in a. vertical plane passing through it axis, this being in a plane transverse to the direction of feed of the work.

The pin 21 is carried by the side members or arms 28 and 2! of a yoke designated generally a by the character 30 in Figs. I and IV. Any suitable means may be provided for retaining the pin in the yoke arms. A tight fit creating sufficient friction for the purposemay be relied upon, if desired. The arms of the yoke extend in the direction of feed and, due to the freedom of the pin to turn upon its axis within the socket provided between the

walls

22 and 22, these arms are adapted to rock .in substantially vertical planes. As will be seen, the yoke 30 is thus permitted to partake of a universal movement with relation to the presser bar I8 and shank It. It may rock longitudinally about the axis of the pin 24 and the latter, in turn, may rock in a transverse direction about the pin 28.

Pivotally mounted upon a pair of studs or screws 3i, extending through and threaded in the

sides

28 and 29 of the yoke 3|), is an advance or forward section 32 of the presser afoot. Upstanding ears 33 on this section are provided with openings into which the screws 3| extend. Elongated apertures 3 are provided through the section 22 to permit the passage of the needle I! into cooperation with the work and the looper means. On its under side, as best shown in Fig. V, section 32 is provided with two longitudinally extending work-engaging

portions

35 and 36, the portion 35 at the left (Fig. III) having its workengaging surface below. that of the portion 28 at the right. The construction is such that normally portion 35 urges the work at the left side of the presser foot against the lower toothed portion l2 of the feed dog while portion 36 of the presser foot extends across the lapped seam and urges the upper of the two layers of fabric 73 being united against the higher toothed portion a whole, and

l3 of the feed dog..

Forwardly extending portions

31 and 38 of section 32 are angled upwardly in relation to the portions 35 and 33,,respectively, and are formed to provide an angled guide channel sewing to direct the work properly in double-lap relation to the point where it is pressed by the section 32 against the feed dog II and throat plate l4. The .work may be lfelled and lapped and directed into the angled guide channel of the presser. foot by means of any appropriateform of -feller 39. This may, for example, be of the type disclosed in the patent to Kucera No. 1,926,950. As best shown in Figs.

I and II, this feller is adapted to receive the edges of the two pieces of

work

40 and 4| and directs them into the channel of the presser foot section .32 in the manner explained.

Arranged in tandem or in line with the section 32 is a second or rear presser foot section 42. This is also pivotally mounted on the yoke 30 by means of a pair of screws 43 extending through the

sides

28 and 29 of the yoke member and into suitable openings in the sides of the section 42. 42 is provided with two

side portionsv

44 and 45 adapted to engage the work at opposite sides of the lapped seam. Portion 44, which is in line with portion 35 of the forward presser foot section, extends to a point somewhat lower than the portion 45, whose under surface is substantially in the plane of the portion 36 of the forward section. Ihe under surface of portion 44 cooperates with a part of the toothedv portion [2 or the feed dog while the under surface of portion 45. cooperates with the rear part of the teeth l3 of the feed dog. Intermediate the

portions

44 and 45 there is formed a recess or chan- In its preferred form the section plate and is engaged by the feed dogh Another spring 35 has one end secured by ascrew 56 to the side of the yoke 33. This spring is looped or bent at 31 through an arc of 180 toprovide an end 58 arranged to extend over the top, of

the rear 33 of section'32 which is adjacent the,

side member 29 of the yoke. The portion 53 of the spring is normally horizontal and cooperates with a flat, horizontal surface at the to of the ear or may fit in a small depression in this ,sunface. Accordingly, the spring tends to hold the forward section 32 of the presser foot in a centralized position in relation to-- the yoke 30. If the front end of this section is tilted upwardly by the work, the forward edge of the ea'r33 is elevated-slightly to further tension the spring 5!. So also, if the rear end of the section 32 is tilted upwardly, the spring will be temporarily tensioned further by the lifting of the rear edge of ear 33 and it will tend torestore the section to its normal positionwhen theseam, or the beneaththe presser foot section.

I like, which has caused the tilting has passed from Referring. now to Figs. III, XI and the operation of the presserfoot under different conditions ,will be seen. Under normal conditions, when the portions of the two work sections to be united that are under-the presser foot are single, flat pieces of material without seams, the presser foot will remain in its normal position as indicated in Fig. III. There will be no transverse tilting of the yoke 30. If a trans- .versely ext'ending'seam is .carried beneath either nel 48 extending the full length of the under a from the description of the operation of the presser foot, to be given hereinafter. The forward end 53 of the section 42, i. e., of the

portions

44 and 45 thereof, is inclined upwardly, as best shown in Fig. VIII, and extend slightly over the rear portion of the forward section 32.- So a also, theforward end 5! of the plate 41 is inclined upwardly, this arrangement being such as to facilitate the proper feeding of the work into the grip of the rear section of the presser foot under allcondit'ions and to enable the desired freedom of relative movement between the two sections of the presser foot.

Attached to a laterally extending shoulder of the shank It, by means of a screw 52, isa spring 53, preferably of loop construction, having its free end 54 extending over and bearing down upon the top of the side member 29'of the yoke 30. Spring 53 thus tends to rock the yoke in a counterclockwise direction (Fig. IV) and urges the forward section 32 of the presser foot into engagement with the work. It will be understood, of course, that the spring Ilia acting upon the presser bar l8 will urge the presser foot as particularly the rear section, against the work as it passes over the throat in the formah tion of a[seam. This will appear more clearly section of the presserfoot, this section will simply tilt in a longitudinal direction as the seam passes but there will still be no transverse tilting of the yoke. On the other hand, when a seam is encountered which extends in whole or in part longitudinally of the double-lap seam being formed on the operation in question, or when some special formation, such as a pocket, places more layers of fabric at one side of the seam than at the other, it will be necessary for the yoke 30 to tilt transversely in one direction or the other, depending upon the nature and position of the particular formation. Thus, at some point there may lie-encountered a previously formed scam in the undier member .40 of the two work pieces being united by a doublelap seam. This will present three layers of the material between the portion 44 of the rear presser root section, for example, and the teeth l2 of the feed dog while only one layer of fabric will be presented between the portion 45 of the presser foot section and the teeth l3 of the feed dog. This will cause transverse tilting of the yoke into the position indicated in Fig. XI. It 1 I is important at this time that the plate 41 be positioned sufliciently high in the channel of the presser foot section to enable parts of the

portions #

4 and 45 to engage the work sections and urge the latter against the teeth of the feed dog.

Referring to Fig. XII, there is indicated a condition encounteredin the formation of another seam in a pair of overalls. Atthe topof this seam there may be encountered fourlayers of fabric on the upper work section, turned under to form eight thicknesses of material, 'while only a single layer of fabric, turned under to form two thicknesses, may be presented by the lower work section 40. In forming this portion of the new seam, it will be necessary t'otilt the yoke 33 transversely in a counter-clockwise direction (Fig.'XlI). While at this time] it is not possible to-provide engagement between the portion ll of the presser foot and the teeth I2 of the feed dog, nevertheless a satisfactory feeding action takes place because of the transverse tilting of the presser foot. It is to be noted that. at this time a limit is provided to the transverse tilting of the yoke .30 bya shoulder 6|! on the of the downwardly extending

portions

22 and 23 of the shank ll are curved, preferably along an are having its center at the midpoint of the pin 24.

While the construction and operation of the improved presser foot have been described in considerable detail, it will be understood that various changes may be made without departing from the general principles and scope of the invention. The terms and expressions used herein have been used as terms of description and not of limitation. I claim:

1. A presser foot for a sewing machine having a presser bar urged toward the work by a spring which comprises a member adapted for connection with the presserbar of the machine, means carried by said member and mounted for universal rocking movement in relation thereto, and work engaging means pivotally mounted on said first mentioned means and arranged to be held against the work by said spring.

2. A presser foot for a sewing machine having a presser bar urged toward the work by a spring which comprises a member adapted for connection with the presser bar of the machine, means carried by said member and mounted for universal rocking movement in relation thereto, and a plurality of separate work engaging means each being provided with coacting convex surfaces for relative universal rocking movement and work engaging means movably attached to said frame member.

6. A presser foot for a sewing machine having a presser bar which comprises a supporting membar, a frame member, a pin carried by said frame pivotally mounted on said first mentioned means and arranged to be held against the work by said spring.

3. A presser foot for a sewing machine having a presser bar urgedtowardthe .work by a spring which comprises a supporting member, means for removably attaching the same to the presser bar of the machine, multi-sectional work engaging means, and means for attaching the sections of said work engaging means to said member, said last recited means comprising a frame member, means pivotally connecting the sections of said work engaging means with said frame member, and a pin for connecting said frame member with said first mentioned member, said pin being arranged for rotation about its longitudinal axis relative to one of said members and being rockable about a transversely extending axis relative to one of said members.

4. A presser foot for a sewing machine having a presser bar which comprises a supporting mem-- ber, means for removably attaching the same to the presser bar of the machine, multi-sectional work engaging means, and means for attaching the sections of said work engaging means to said member, said last recited means comprising a frame, means pivotally connecting the sections of said work engaging means with said frame, and a pair of pins carried by said member and frame respectively, said pins having coacting curved surfaces and having their axes disposed at an angle with relation to each other to promember, said pin and said supporting member being provided with coacting convex surfaces for relative universal rocking movement, means on said support for retaining said pin in cooperative relation to said surface of the support, and work engaging means movably attached to said frame member.

7. A presser foot for a sewing machine having a. presser bar which comprises a supporting member, a frame member, a pin carried by said frame member, said pin and said supporting member being provided with coacting convex surfaces for relative universal rocking movement, coacting guide surfaces on said members for limiting the relative bodily movement thereof, and work engaging means movably attached to said frame member.

8. A presser foot for a sewing machine having .a presser bar which comprises a supporting member, a frame member, a cylindrical pin carried by said frame member, means on said supporting member for receiving said pin in a manher to permit turning thereof and limited relative rocking thereof about a line transverse to the axis of the pin, said supporting member and socket being constructed and arranged to enable relative universal movement between said frame member and said supporting member and work engaging means pivotally attached to said frame member.

10. A presser foot for a sewing machine hav ing a presser bar which comprises a supporting.

and work engaging means pivotally attached to said frame member.

11. A presser foot for a sewing machine having a presser bar which comprises a supporting member, means for attaching said member to the presser bar, a yoke member, means for connecting said yoke member with said supporting member including a pin tiltable, in a plane through its axis with respect to one of said members and rotatable about its axis with respect to one of said members, said pin being held against lengthwise movement with respect to one of said members, means for limiting relative bodily movement of said members, and work engaging means movably carried by said yoke member.

12. A presser foot for a sewing machine having a presser bar which comprises a supporting member, means for attaching said member to the presser bar, a yoke member, means for connecting said yoke member with said supporting member including a pin tiltable in a plane through its axis with respect to one of said members and rotatable about its axis with respect to one of said members, means for limiting said tiltability of said pin, said pin being held against lengthwise movement with respect to one of said members, means for limiting relative bodily movement of said members in the direction of the axis of said pin, and work engaging means movably carried by said yoke member.

13. A presser foot for a sewing machine having a presser bar which comprises a supporting member, means for attaching said member to the presser bar, a yoke member, means for connecting said yoke member with said supporting member including a pin tiltable in a plane through its axis with respect to one of said members and rotatable about its axis with respect to one of said members, said pin being held against lengthwise movement with respect to one of said members, means for limiting relative bodily movement of said members, a work engaging member rockably mountedon said yoke beneath said supporting member, and a second work engaging member rockably mounted on said yoke in line with and in advance of said first mentioned work engaging member.

14. A presser foot for a sewing machine having a presser bar which comprises a supporting member, means for attaching said member to the presser bar, a yoke member, means for connecting said yoke member with said supporting member including a pin tiltable in a plane through its axis with respect to one of said members and rotatable about its axis with respect to one of said members, said pin being held against lengthwise movement with respect to one of said members, means for limiting relative bodily movement of said members, a work engaging member rockably mounted on said yoke beneath said supporting member, a second work engaging member rockably mounted on said yoke in line with and in advance of said first mentioned work engaging member, and spring means normally urging said yoke member in a direction to force said second work engaging member against the work.

15. A presser foot for a sewing machine having a presser bar which comprises a supporting member, means for attaching said member to the presser bar, a yoke member, means for connecting said yoke member with said supporting member including a pin tiltable in the direction of its axis with respect to one of said members and rotatable about its axis with respect to one of said members, said pin being held against lengthwise movement with respect to one of said members, means for limiting relative bodily movement of said members, a work engaging member rockably mounted on said yoke beneath said supporting member, a second work engaging member rockably mounted on said yoke in line with and in advance of said first mentioned work engaging member, spring means normally urging said yoke member in a direction to force said second work engaging member against the work, and means for urging said second work engaging member into a centralized position with relation to said yoke member.

16. In a sewing machine a work support, a feed dog in said support, a head extending over said work support, a presser bar in said head, a spring for urging said bar downwardly and a presser foot carried by said bar arranged to hold the work against said feed dog, said presser foot including a support member attached to said presser bar, a frame mounted on said support member for both longitudinal and transverse rocking movement, and a plurality of work engaging members rockably mounted on said frame and arranged to be held against the work by said spring.

FRANK A. KUCERA.