US2092735A - Attachment for sewing machines - Google Patents

Description

Sept. 7, 1937. J. D. KARLE ATTACHMENT FOR SEWING MACHINES Filed Nov. 2, 1935 2 Shee'ts-Sheet 1 John 0. Earle Sept. 7, 1937. J. D. KARLE ATTACHMENT FOR SEWING MACHINES 2 Sheets-Sheet 2 Filed Nov. 2, 1935 Wifues: MN

Patented Sept. 7, 1937 PATENT OFFICE" ATTACHMENT FOR SEWING MACHINES John 1). Katie, Roselle Park, N. 1., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application November 2, 1935, Serial No. 47,932

15 Claims.

This invention relates to attachments for sewing machines, and has for its primary object to provide an improved attachment to be used with the usual family type sewing machine for producing an ornamental seam.

Another object of the invention is to provide a new and novel ornamental seam.

Another object of the invention is to provide a new and improved form of piercing element which will more efl'ectively pierce a hole in the work in advance of the usual needle and to provide means for causing the piercer to pierce the work during predetermined stitch-forming cycles.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations, and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

Figure 1 is a front elevation of an embodiment of the improved attachment which forms the subject of the invention, showing the position of the parts when the needle is in its highest position at the begnning of the cycle of operation.

Figure 2 is a front elevation of the attachment showing the needle in its lowest position and the piercer in its ineffective position.

Figure 3 is a front elevation of the attachment, showing the position of the parts at the completion of the left to right shifting movement of the presser-foot.

Figure 4 is a front elevation of the attachment showing the-piercer and needle in their lowest operative positions.

Figures 5 and 6 are, respectively, rear and side elevations of the attachment.

Figure 7 is a top plan view of the presser-foot.

Figures 8 and 9 diagrammatically illustrate the ornamental seam produced by the attachment.

Figures 10, 11 and 12 are enlarged views illustrating the action of the plercer on the material on its descending and ascending stroke.

Figure 13 is a sectional view taken substantially along the line l3 l3 of Figure 10.

The attachment is shown applied to the usual family type sewing machine having a reciprocatory needle-bar in carrying a needle I I, a presserbar 12 (Figs. 5 and 6), a throat-plate i3 and a four-motion feed-dog I4 for advancing the work, all of which are old and well known in the art.

In the embodiment illustrated, the attachment 55 comprises a channel block l5 adapted to be secured to the angular lower portion of the presserbar by the screw 16. Carried by the block I5 is a plate l1 having an upstanding inclined arm 13 and a cross-arm l9. Slidably held by the rivets 20 on the cross-arm i9 is a slide-bar 2| having a depending portion 22 to which is secured by means of the screw 23 the presser-foot 24, hereinafter described. Fulcrumed upon the upstanding arm 18 of the plate l1 by the pivotscrew 25 is a swinging member 26 having its lower end 21 extending down between an adjustable eccentric stop 28 and the knurled headed adjustable stop-screw 29 both of which are carried by the slide-bar 21. The swinging member 26 has an opening 30 with inwardly extending projections 3| and 32 adapted to embrace a cam-element 33 having a' plurality of circumferentially spaced projections, (Fig. 5). Fixed to the cam-element 33 is a ratchet-wheel 34, and the cam-element and ratchet-wheel are rotatably mounted on the plate I1 by means of the bearing pin 35. Secured to the needle-bar Ill by the usual set-screw 36 is a needle-clamp 31 having a laterally extending arm 38 which pivotally supports a spring biased pawl 39 which is adapted to engage and actuate the ratchet-wheel 34 when the machine is operated. The above described mechanism is the same as that shown and described in the Karle Patent No. 1,997,419, dated Apr. 9, 1935, to which reference may be had for a more detailed description. Carried by the pivot-pin 35 and fixed to the ratchet-wheel 34 so as to rotate therewith is a gear 40 which meshes with a gear 41 rotatably secured by the pivot-stud 42 to the laterally extending arm 43 of the plate 11. The gear 41 meshes with a gear 44 having fixed thereto a cam 45, the gear 44 and cam 45 being secured by the pivot-screw 46 to the arm 43 of the plate 11.

Swingably carried by the pivot-screw 25 is a cam-lever 41 having a cam-portion 49 and a laterally extending step-like portion 48 which cooperates with the cam 45. Pivoted to the needleclamp 31 by means of the pivot-screw 52 is a T- shaped lever carrying a piercer 5|. The lever 50 is constantly urged in a clockwise direction about its pivot by a helical wound spring 53 (Fig. 6) which has one of its ends reacting against the pivot-screw 52 and its other end reacting against the T-shaped lever. To normally maintain the piercer in a vertical position the needleclamp 31 is provided with a stop 54 which is engaged by one of the limbs of the T-shaped lever 50. The other limb 55 of the T-shaped lever 50 is in a position to engage the cam portion 49 of cat'es again and enters the material is turned 180 the lever 41 to swing the lever ill and move it to its ineffective position as shown in Figure 2.

The presser-foot 24 is formed with a piercer opening 56. (Fig. 7), an elongated needle opening 51 and-a forwardly extending finger II with a guide 58 for the purpose of guiding the work to the sewing instrumentalities.

Operation Assuming the needle-bar to be in its raised position and the parts in the position shown in Fig. 1, upon operation of the machine, the needle descends through the material at the point a (Fig. 8) and the end of the limb 55 of the T- shaped lever 50 engages the cam portion 40 of the lever 41 and swings the T-shaped lever III in a counter-clockwise direction. againstthe action of the spring 53, about its pivot 52 to the position shown in Fig. 2, thereby rendering the piercer ineffective to pierce the material. On the upstroke of the needle-bar the pawl ll engages the ratchet-wheel 34 and imparts to it oneeighth of a revolution which, in the well known manner, causes the presser-foot 24 to be shifted to the right to the position shown in Figure 3. The gear 40 being fixed to the ratchet-wheel 34 causes the cam 45, through the gears 4| and 44, to move from the position shown in Figs. 1 and 2 to the position shown in Fig. 3. The feed-dog I! then operates to advance the work and the needle on its next descent enters the previously formed opening A (Fig. 8) in the material laying the thread I) and as the cam 45' has moved to the position shown in Fig. 3 the arm 4'! is free to swing on its pivot thereby permitting the piercer 5| on this descent to pierce the material to form the opening B. On the upstroke of the needle the stitch is completed and the pawl 38 again actuates the ratchet-wheel 40 and, by the mechanism previously described, causes the pressor-foot to be shifted to the left to the position shown in Fig. 1 and the cam 45 to assume the position shown in Fig. 1, the material being fed forward by the feed-dog. The needle reciprothe material at the point a laying the thread c; the piercer is rendered ineffective on the downstroke of the needle and on the upstroke of the needle the next stitch is completed. The cycle of operation of the attachment is repeated, the piercer forming an opening in the material Bil during alternate reciprocations of the needle. the material being shifted laterally of the needle and advanced by the feed-dog, and the needle entering the previously formed piercer openings and then the body of the material at one side of the piercer openings, until the end of the seam is reached. The material may then be out along the openings A, B, C, thus forming a picot edging, or if desired the material may be turned 180 and fed through the machine a second time thereby forming the open-work seam shown in Fig. 9, the arrows indicating the direction of feed of the material. It is to be understood that, when and the cycles of operations repeated. the piercer descends through its previously formed openings.

It will be observed that the two rows of opposed zigzag stitches are located on opposite sides of the line of pierced openings A, B, C, etc. and alternate penetrative portions of each row of stitches pass through the openings and the other penetrative portions of the row of stitches pass through the body material outside said openings. The stitches diverge from the openlugs and this arrangement effectively ties back the threads around the openings, thereby preventing them from spreading and partially closing said openings.

As shown in Fig. 10, the piercer, indicated generally as II, descends through an opening ll in the throat-plate I3 and as a result the threads of the material 80 are crowded down into the opening ti thereby leaving a "burr" on the lower face of the material. In order to provide a pierced hole'free from cross-threads, it is essential that the "burr" be carried to the upper face of the material before the material I is shifted. otherwise the depressed threads will engage the wall of the opening 6| and be forced upwardly into the plane of the material thereby partially closing the hole.

To carry the depressed threads to the upper face of the material the piercer II is formed with a cone-shaped point 82 and a relieved shank 63 of less diameter thereby forming a rounded shoulder 84 at the Junction of the shank and point. The shoulder 84 functions to carry the threads. which are depressed during the downward movement of the piercer, to the upper face of the work upon the retraction of the piercer, as illustrated in Figs. 11 and 12.

The expression "forward" as used in the foregoing specification and appended claims is to be understood as indicating the direction away from the operator at the front of the machine and the expression row of zigzag stitches" means a row of stitches in the production of which an endwise reciprocatory needle and the work are relatively vibrated laterally of the row consecutively in opposite directions.

From the foregoing description considered in connection with the accompanying drawings. the construction, manner of operation and several advantages of my improved attachment for a sewing machine will be clearly and fully understood. It is apparent that such a device has a wide variety of uses, and it will be understood that the form, construction and arrangement of the several elements employed may be varied. Therefore, the privilege is reserved of resorting to all such legitimate changes therein as may be fairly embodied within the spirit and scope of the appended claims.

Having thus set forth the nature of the invention. what I claim herein is:-

l. A sewing machine having in combination. a reciprocatory needle, a presser-ioot, means for vibrating said presser-foot and needle relative to each other. a piercer for making a hole in the work through which the needle descends. means for reciprocating said piercer, and means for rendering said piercer ineffective to pierce the work during alternate needle-reciprocations.

2. A sewing machine having sewing instrumentalities including a needle, a piercer for making a hole in the work through which the needle descends, means for reciprocating said needle and piercer, and means for rendering said piercer ineffective to pierce the work during alternate needle reciprocations.

3. In combination with a sewing machine having sewing instrumentalities including a reciprocatory needle. an endwise reciprocatory fabricpiercer comprising a shank, a cone-shaped piercing head at the lower end-oi the shank. said head having a base portion which is larger than said shank forming a step-like shoulder extending around the base of the head for inverting, upon retraction of the piercer, the burred edge of the hole formed in the fabric on the downward stroke of the piercer.

4. In combination with a sewing machine having sewing instrumentalities including a reciprocatory needle, an endwise reciprocatory fabricpiercer located in advance of said needle and comprising a shank, a cone-shaped piercing head at the lower end of said shank, said head having a base-portion which is larger than said shank thereby forming a shoulder at the junction of the shank and head of suflicient abruptness to inv'ert, on the upward stroke of the piercer, the burred edge of thehole formed in the fabric on the down-stroke of the piercer.

5. An attachment of the character described adapted to be secured to the presser-bar of a sewing machine and comprising means actuated by the reciproctory needle-bar of the sewing machine for imparting to the material being acted upon a lateral shifting movement relative to the needle, and means including 'a piercer for making an opening in the material, said piercer being formed with a cone-shaped point and a relieved shank of less diameter than the base of the cone-shaped point.

6. An attachment of the character described adapted to be secured to the presser-bar of a sewing machine and comprising means actuated by the reciprocatory needle-bar of the sewing ma chine for imparting to the material being acted upon a lateral shifting movement relative to the needle, and means including a piercer for making an opening in the material, said piercer being formed with a shank, a cone-shaped point having a base larger than the shank thereby forming a shoulder at the junction of the shank and point.

'7. An attachment for sewing machines having sewing instrumentalities including a reciprocatory needle-bar carrying a needle and a feeding mechanism for imparting a forward feeding movement to the work during each needle-reciprocation comprising means actuated by the reciprocatory needle-bar for imparting to the material being acted upon a lateral shifting movement relative to the needle during each stitch-forming cycle, and a piercer'for making an opening in the material during alternate stitch-forming cycles.

8. A sewing machine having in combination, a reciprocatory needle-bar carrying a needle, feeding mechanism tor-imparting a forward feeding movement to the work during each needle-reciprocation,.meansfor relatively shifting the needle and the work transversely of the direction of feed during each stitch-forming cycle, a piercer for forming an opening in the material through which the needle descends, and means for driving said piercer through the work once only for a plurality of needle-reciprocations.

9. A sewing machine having in combination, sewing instrumentalities including a reciprocatory needle, feeding mechanism for advancing the work for each needle-reciprocation, a reciprocatory piercer for forming an opening in the work through. which the needle descends, means for causing said piercer to pierce the work once only for a predetermined number of needle-reciprocations and means for relatively shifting the needle and the work laterally whereby said needle descends through theopening in the work formed by the piercer and then through the work at one side'of the opening.

' 10. A sewing machine having in combination,

sewing instrumentalities including a reciprocatory needle, means for actuating said needle, a piercer, actuating means for reciprocating said piercer in timed relation with the needle reciprocations to form apertures in the work for entrance by said needle in alternate reciprocations of the needle and to suspend the effective operation of the piercer between said alternate reciprocations of the needle.

11.. In combination with a sewing'machine having a reciprccatory needle, means for actuating said needle, piercing mechanism including a piercer having a point which enters the work to form a hole through which the needle descends, means for relatively shifting the needle and the work laterally, and feeding means for advancing the work relative to the needle thereby causing said needle to make a stitch in the work in ad-. Vance of and at one side of the piercer opening, said piercer remaining'above the work when said stitch is formed.

12. A sewing machine having in combination, I

sewing instrumentalities including a reciprocatory needle, loop-taking means coordinated therewith to form stitches, means for advancing the work relative to the needle and for laterally shifting the work and needle relative to each other once for each needle-reciprocation, thereby forming a zigzag stitch, a piercer, and means for causing said piercer to make an opening in the work through which the needle descends for alternate needle-reciprocations.

13. A sewing machine having in combination, sewing instrumentalities including a reciprocatory needle, piercing mechanism including a piercer for making an opening in the work during alternate reciprocations ot the needle, means for advancing the work relative to the needle and for laterally shifting the work and needle relative to each other for each needle-reciprocation thereby forming a row of zigzag stitches, alternate penetrative portions of the row of stitches passing through the openings formed by the piercer and the other penetratlve portions of the row of stitches passing throughthe work outside of said openings.

14. An attachment forsewing machines having sewing instrumentalities including a reciprocatory needle, feeding mechanism for advancing the work during each needle-reciprocation, comprising a piercer pivotally connected to the needle-bar, means for rendering said piercer inefiective to pierce the work during predetermined reciprocations of said needle-bar, a presser-foot, andmechanism for shifting said presser-foot laterally of the line of feed for each reciprocation of the needle-bar. v

15. An attachment for sewing machines having sewing instrumentalities including a reciprocatory needle, feeding mechanism for advancing the work during each needle-reciprocation, comprising a piercer pivotally connected to the needle-bar, means for swinging said piercer about its pivotal connection during predetermined reciprocations of said needle-bar, and mechanism for relatively shifting the needle and the work laterally Ior each reciprocation of said needle.

.Jorm n. KARLE;

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