US2346467A - Skip stitch machine - Google Patents

Description

April 11, 1944.

l. E. BILLS 'EI'AL SKIP STITCH MACHINE Filed Dec. 12. 1939 4 Sheets-Sheet 2 INVENTOR William B. Pdfey Ira 1 517/5 W 77% v A TTORNE Y April 11, 1944.

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SKIP STITCHMACHINE Filed Dec. 12. 1939 4 Sheets-Sheet 5 1 INVENTOR William 5. Pafe & I'm

A TIURNEY April 11, 1944. I. E. BILLS EI'AL SKIP STITCH MACHINE 4 Sheets-Sheet 4 Filed Dec. 12, 1959 Fl a. 8.

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INVENTO William B. Pafe Ira E. B/Y/s Patented A r. 11, 1944 SKIP STITCH MACHINE Ira E. Bills and William B. Patey, Dalton, Ga.

Application December 12, 1939, Serial N0. 308,840

3Claims.

Our invention relates to tufting machines and more particularly to tufting machines of that character which incorporate yarn into fabric at intervals to form dots over the upper surface of the fabric very much in the manner or style of handmade "candlewick" spreads.

These decorative dots or tufts were made by passing yarn or the like back and forth through the fabric at spaced intervals to form stitches, then clipping the yarn with scissors or other appropriate means to form tufts.

Bedspreads of this character have been made for years by hand until recently when the Federal wage-hour bill was applied to that industry. Since that time, the cost of manufacture has been practically prohibitive, and hand-tufted spreads are now only a memory.

Efforts had previously been made in the prior art to produce a machine for making these particular articles, but the competition of handmade spreads reduced the demand for these ineflicient, wasteful types of machines.

An example of these efiorts is disclosed in Boyce, 1,984,332, where grippers are used to remove the long strand of yarn bridging the space between groups of stitches. uch a complicated mechanism would have to be operated at such a low speed that it would not even now be very successfully and profitably used. The grippers pull out the strands of yarn between the tufts and this becomes waste, adding to the expense of operation. And further there is no positive means for maintaining the needle in upright position.

It is true that latching arrangements have been attempted to be used to maintain the needle bar in uppermost position, but the manner of their action causes great impact and vibration in the machine making it very difiicult to operate and resulting in great wear of the parts.

Applicants with a knowledge of all of these defects in and objections to the prior art have for an object of their invention the provision of a skip stitch machine which eliminates the waste of yarn bridging the space between groups of tufts.

Applicants have as a iurther object of their invention the provision of a tufting machine which eliminates the use of grippers for removing strands of yarn between groups of tufts with resulting simplicity in construction and increased speed in operation.

Applicants have as another object of their invention the provision of a skip stitch machine between groups of tufts, and therefore substantially eliminates waste of yarn.

Applicants have as another object of their invention the provision of a skip stitch machine employing an impact absorbing means to absorb all shocks resulting from sudden starting and stopping of the needle bar.

Applicants have as a still further object of their invention the provision of a, skip stitch machine employing a reciprocating needle with a brake for gradually stopping and finally locking the reciprocating needle in upper-most position when disengaged from the power source, without great impact and wear on the parts.

Applicants have as a still further object of their invention the provision of tensioning mechanisms on a skip stitch machine to place the yarn carried by the reciprocating needle under such tension as to absorb in the form of slack the yarn bridging the space between groups of tufts after it is cut and to be of sumcient force to draw the cut tails of yarn through the pierced fabric to its under side.

Other objects and advantages of our invention will appear from the following description and accompanying drawings and the novel features thereof will be particularly pointed out in the annexed claims,

In the drawings, Figure 1 is a side elevation of our attachment, showing the attachment casing and a fragment of the sewing machine head, to which it is attached, partly in section.

Figure 2 is an end view of a sewing machine head showing the special mechanism for tensioning thread in a machine having our attachments.

Figure 3 is a front view of the sewing front of a sewing machine head showing the tensioning mechanism of Figure 2 from a different angle.

Figure 4 is a detail of the needle bar. stopping mechanism, shown in and elevation.

Figure 5 is aside view detail of the shaft interlock and driving mechanisms, shown in the out of clutching position.

Figure 6 1s an end view of the sewing head of a sewing machine with the connection between the needle shaft and the needle bar and showing a tufting attachment beneath the bedplate.

Figure '1 is a plan view of-a sewing machine head bearing our attachment. the top of the easing being removed to show the attachment.

Figure 8 is a detail showing the first step of the needle in position to pierce the fabric for the first of the group of stitches.

which eliminates the bridging stitches of yarn Figure 9 shows-the second step -immediatelv direction, imparting power and torque to collar sion spring 99 and adjustable screw cap. 99.

Thence the thread passes through the eye of needle H.

In Figure 6 needle crank 12 is rigidly fastened to the end of needle shaft 9 and rotated thereby. Connecting arm I4 is movably fastened at one end to needle crank 12 by pin 13 and is movably connected at the other end to needle bar 92 by means of brace 9i and brad 15, so that needle bar 52 moves up and down by the rotation of needle shaft 5. A tufting attachment is shown below the bedplate of the sewing machine head. The feed dog is operated by feed advance shaft I9 and feed lift shaft 11, which are pivoted in the frame of the sewing machine head i. Both the tufting hook and the tufting blade 9i are operably connected with a central shaft beneath the sewing ma-- chine bed by means of oscillating pivot point I9, which is fastened to the end of the central shaft and pivot point 19 which is affixed to an adjustable plug 93. The action of the feed dog and tufting attachment is independent of the needle shaft 5. Any conventional tufting attachment may be used which normally retains one or more uncut loops upon the tufting hook, so that the tension of the thread will not pull the thread out of the fabric until the last loop is clipped. Such an attachment is shown in Bradwell, 2,038,923, Boyce, 1,963,348, and 1,963,349, or others.

The needle II is held in the needle bar by the collar 19, which also carries the tensioning means 91 comprising the two disks urged together by the compression spring 69 and the adjustable screw cap 69. The tensioning device 59, 69, previously described is also of the same character. Conventional presser foot and feed dogs may be used,

although the latter are not shown in the draw ings.

Referring more particularly to the tufting attachment which includes a downwardly projecting frame 82 secured to the lower face of the work support of bedplate of the machine and projecting downwardly therefrom. It comprises a, relatively thin hard steel rest shaped with a split lower end for the reciprocation of a plug 93 and a tightening means for urging the two arms of the split frame toward each other to grip the plug 93. To an off-centered portion of the plug is mounted a pin 19 which carries the looper 90 in pivotal relation therewith and also serves as a mounting for cutter 91, which has a lower end which fits over the pin 19 and rides up and down thereon during the cutting operation. Passing through an opening in the upper portion of the frame 92 is a shaft or collar on a shaft having a pin 19 projecting forwardly therefrom and in offcenter relation thereto. This pin carries the cutter 8| and serves to reciprocate it up and down into cutting relation with the looper 99. Pin 19 also serves the purpose of engaging the fork on the looper and swinging it back and forth since the central shaft upon which the pin 19 is mounted partially rotates'alternately in opposite directions.

The operation of this machine is somewhat, as follows:

The head i, which includes not only the upper sewing machine portion of conventional structure but also the bedplate or work support and various associated mechanisms for operating the machine, is set upon a machine stand or operating table where power may be applied to it by means of a belt or other mechanism that passes over pulley 20. The movement of this pulley rotates the hand wheel i9 in ordinary counter-clockwise 1i whbh is rotatably located on shaft 4. This in turn acts through pin 22 and tends'to coil spring.

25. The'coiling of this spring gradually imparts more power and torque to shaft 4 since it acts through collar 23 thereon. Shaft 4 then begins its rotation causing the worm ll mounted thereon to rotate with it, also rotating coupling 9 and its clutch end ii. Rotation of worm ll imparts a clockwise rotation to gear 25 and cam 29 but roller 99 of arm 94 being in contact with the raised face of cam 29 mounts such arm in raised position and acts through pin 9 to maintain clutch end ll out of engagement with clutch end l2. This permits the needle bar shaft 5 to remain in inoperative position thus permitting the needle bar to remain upward, while cloth is being carried through the machine lying on the upper face of the bedplate by means of the feed dogs, not shown, actuated by their feed dog shafts l9, l1, and in'cooperation with the presser foot. However, the needle ii is locked in uppermost position and does not pierce the fabric, although the hook 90 swings back and forth across the plane of the path of the movement of the needle and the cutter reciprocates up and down into and out of cutting relation with the looper. However, the needle being mounted in upper-most position does not pierce the fabric and forms no loops which the looper can catch and the cutter can sever. Finally, the gear 29 has turned around until face 29 has come into engagement with roller 33 and the finger or extension from the arm or rod 34 acting under the pressure of the tension spring 35 moves down upon the lower face of the cam. This movement of arm 34 imparts a clockwise movement to the extensions of such arm about the pivot 31, thus relieving pressure upon the end of plunger i5, and, at the same time, the pin 9 acts upon the sleeve or coupling 9 to move it longitudinally on shaft 4 toward the reciprocating needle causing the clutch end I l to come into contact with the face of clutch end l2 and to ride thereon until the teeth 49, 49, seat in the notches 41, 50, and lock the two clutch ends ii and I2 together. When they are locked together the needle bar shaft 5 rotates with the shaft 4 and carries the member 12 with it. This causes the pivot pin 13 to move in a circle and raises and lowers arm 14, which is attached to the needle bar causing it to reciprocate up and down. A detail of the needle Ii and looper 99 and cutter 8|, as well as the fabric on the bedplate 94, is shown in Figure 8. Reciprocation of the needle bar continues so long as the roller 33 rides along the lower surface of cam 29. It first moves downwardly carrying its strand of yarn with it. Figure 9 shows the needle after it has pierced the fabric, reached its lower-most position and started back up through the fabric. Tension being applied by the tensioning means 59, 99 and 51, 69 to the strand of yarn 95, the end 85 is drawn down through the pierced cloth by the upward movement of the needle Ii in cooperation with the looper which holds the loop. As the needle leaves the fabric, as shown in Figure 10, the end 99 of the yarn has already been pulled through the pierced fabric. The feed dogs operate and move the fabric through the machine I 11 and 12, as the needle again reaches the fabric.

The looper then passes back out of the plane of the path of the needle and the cutter ll comes up into cutting position as shown in Figure 12, but does not clip the loop since the loop, is on beyond the end of the cutter. Then the needle moves down through the fabric again, piercing the cloth and reaching its lower-most position, and starts its upward movement, at which time the looper passes between the strand of yarn and the needle, and the inner-most loop is moved into cutting relation with the cutter 8i. This is shown in Figure 13. Then the needle again moves out of the fabric and the cutter 8| clips the loop on the looper as such looper moves back out of the plane of the path of the needle. This leaves only the last loop on the looper. By this time, the roller 3| has reached the extremity of the lower portion of the cam 28 and rides up on its shoulder to the high portion 80. This causes the arm 34 to swing counter-clockwise and the pin 9 slides the sleeve longitudinally on the shaft 4, disengaging the faces of clutch ends II and I2 from each other.

At the same time the end of the screw 38 engages the end of plunge l pressing it downwardly. The downward movement of the plunger 15 causes the stop plate ii to press on the cam 44, Previous to this, it was idling up and down on that cam surface. When the flat surface of the stop plate I! comes into contact with the diagonal surface of the cam 44, the shaft 5 is locked in position and the needle bar is maintained in its upper-most position, as shown inFlgure 14.

As the shaft 4 continues to rotate, roller it continues to ride over the raised portion of cam 28 and maintains the clutch and faces II and I! out of engagement with each other. At the same time the stop plate It imparts great pressure to the diagonal surface of the cam 44 maintaining the needle in locked upward position. The feed dogs progressively move the cloth through the machine and the last loop on the looper 80 slides back and is severed by cutter 8|, as shown in Figure 15.

This operation is continued with the looper II and cutter 8! going through their regular cycles but having no loops placed thereon eflfects no cutting action and forms no new tufts. The cloth continues to move over the bedplate of the machine and the strand of yarn 85 being held by tensioning devices 59, i0 and 68, 89, create a stretch in the strand 85 of-sumcient magnitude to cause the end of the strand to be slowly but continuously pulled out of the cloth.

Figure 16 shows the end of strand 85 just before it leaves the cloth.

This operation is continued until the cloth has again moved to the point indicated in Figure 8. At this time the roller 13 has reached the farther extremity of the raisedportion of the not cause an impact in the machine, but is gradv ually taken up by the spring II, which transmits a torque from collar 2| to collar 23. The cycle of operations is therefore begun all over again a and a new set of tufts are placed in the cloth.

Having thus described our invention, we claim: 1. An apparatus of the character described comprising the drive shaft of a sewing machine head, a needle bar and a needle carried'thereby for passing thread through fabric positioned in said machine, clutch elements for putting said needle bar into and out of operative connection with said drive shaft, a control element cooperating between said drive shaft and said clutch elements, whereby to open and close said clutch elements responsive to the rotation of said drive shaft and to continue and discontinue the operation of said needle, means positioned beneath the bedplate of the machine, reciprocating with 20 said needle for hooking said thread to form loops and clipping said loops to form tufts, means for carrying said fabric beneath said needle and braking means for stopping said needle bar in upraised position when said clutch elements are out of clutching engagement, whereby to form tufts grouped in said fabric at intervals spaced according to the continuance and discontinuance of operation of said needle.

2. An apparatus of the character described comprising the drive shaft of a sewing machine,

a needle bar of said sewing machine and a needle carried thereby, said needle bar being activated by a needle bar shaft; engageable clutch elements for putting said drive shaft and needle bar shaft into and out of operative connection; cam control means activated by said drive shaft for engaging and disengaging said clutch elements at intervals, whereby to continue and discontinue the operation of said needle; and braking means responsive to said cam control means and cooperating with said needle bar shaft to stop said needle bar and needle in up-raised position when said clutch elements are disengaged, permitting the free passage of fabric beneath said stopped needle.

3. A skip-stitch machine of the character described comprising a reciprocating needle bar carrying a needle for passing a strand of yarn down through a fabric, a drive shaft for posi- 99; tively actuating said needle bar up and down,

a clutch element on said drive shaft for operatively engaging a clutch element connected with said needle bar, whereby to put said drive shaft and needle bar into and out of operative connection, means responsive to rotation of the drive shaft for periodically disengaging said clutch elements to render the needle bar inoperative, and means for rigidly maintaining said needle bar in raised position when the needle bar is #9 rendered inoperative by the disengagement of said clutch elements.

IRA E. BILLS. WILLIAM B. PATEY.

April 11, 1944. l K AL 2,346,468

MACHINE FOR FORMING RESILIENT BRACKETS Filed April 22, 1942 4 ShGGtS-SIIBGt 1 AWE I v Aka/v E. 5E/CKM4A/ a/rd

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