US2333689A - Spaced tufting machine - Google Patents

Description

Nov. 9, 1943. v. J. SIGODA SPACED TUFTING MACHINE Filed Nov. .21 1941 2 Sheets5heet 1 INVENTOR.

' 9 1 43. v. J. SIGODA 2 333,689

SPACED TUFTING MACHINE Filed Nov. 21 1941 I 2 Sheets-Sheet 2 1N VENTO War? I 29659912 BY Patented Nov. 9,1943

2,333,689 I srAcEn TUFTING MACHINE Victor J. Sigoda, Great Neck, N. Y., assignor to Man-Sew Corporation, New York, N. Y., a corporation of New york Application November 21, 1941, Serial No. 419,940 7 Claims. (01. 112-79) .My invention relates to that class of sewing machines known as tufting machines. More specifically, it relates to an improvement in the standard Singer type sewing machine which has previously been converted or rebuilt for tufting usage.

This conventional type machine produces a continuous line of tufting stitches. My invention adapts such a machine to produce spaced groups of tufting stitches. stitches, and the amount of space between the groups of stitches is variable, and therefore permits the simulation of hand tufting on such articles as bedspreads in what is known as candle: wick style. It is also useful in embroidery applications where the great flexibility permits unusual ornamental effects to be obtained. The formation of intricate designs is made possible by means of controlled variations in the spacing of the groups of tufts, and if desired, in the number of stitches in each group.

In addition to the foregoing objects, I have also desired to develop a machine of this class that is of considerably simplified structure. This has been achieved with, a minimum of parts, and with the elimination of such unsatisfactory control mechanisms as clutches, friction drives, pin and latch catches, springs and the like, all of which not only complicate the structure, but give rise to constant service and maintenance problems which my structure avoids.

This simplified structure has resulted in a machine of relatively high efliciency, and reduced cost, with lower maintenance and service requirements. In addition the improvement results in a machine that is positive in operation, and practical and reliable in sustained high speed usage.

By my invention, I have also desired to make Both the number of v the standard Singer type converted tufting machine readily adaptable to the production of controlled, variable spaced tufting, without undue reduction of speed of operation.

A further object has been to devise a machine that permits great flexibility in ,the selection of the predetermined spacing between groups of tufts, and which is readily adaptable by the simple change of one part, which can be made even by a mechanically untrained operator of the machine, to provide for a variation in the number of stitches in each group of tufts from a single stitch to a, number of stitches. Furthermore, by this simple change of parts, the machine can be quickly converted back to continuous stitching without loss of use of the variable spacing feature.

The manner in which I have achieved the foregoing objects will become apparent from the following detailed description of the preferred embodiment of my invention shown in the drawings, in which:

Fig. 2 is a front elevational view corresponding to Fig. 1.

Fig. 3 is a perspective view, partly in section, of the essential operating mechanism of my invention, taken on line 3 3 -of Fig. 1, looking toward the mechanism from the back of the machine.

- Fig. 4 is a sectional view taken through the arm of the machine to which my invention has been applied, on line l4 of Fig. 1.

Fig. 5 is a side elevational view taken on line 5-5 of Fig. 2, showing the linkage between the needle bar and the actuating lever.

Referring now in detail to the drawings, numeral ll represents a standard Singer typ sewing machine previously converted for tufting usage, to which my invention has been applied.

I disconnect the usual needle bar crank (not shown) from the armshaft I3. I then provide armshaft l3 with a worm I4, held in place by a set screw or a fastening pin, IS.

The top of the arm Illa is milled to accommodate a casting 20, which serves as a housing for a gear i8 engaging worm M; as a support for a cam shaft i9; and as a support for an actuating lever 30.

Worm gear i6 is mounted on cam shaft l9 through its hub H, by means of a set screw or a fastening pin I8.

Cam shaft I9 is journalled in bosses 2i and 2 la of casting 20, so as to be freely rotatable. On one end of shaft iii, a cam disk 22 is mounted by means of a set screw 24 passing through the hub 23 of cam disk 22.

Cam disk 22 has a roller groove or path 25 milled in its operating face. Groove 25 consists 'of a concentric portion and a portion that varies from the concentric center line by an amount of displacement occasionedv by a series of lobes, A,

B, C and D. The extent of lobes A, B, C and D is proportioned by the amount of reciprocating action desired on needle bar actuating lever 30.

The groove 25 is designed to accommodate a ,roller cam follower 33, freely mounted on a stud 34 on arm 32 of lever 30, and to thereby cause arm 32 to reciprocate backward and forward in accordance with the variations in the groove 25. Byutilizing a groove with side walls to guide roller 33 on arm 32, I eliminate the necessity forthe use of springs or other means to keep arm 32 moving in the desired reciprocation without lag. Needle bar actuating lever is shown as a bellcrank type. A straight type lever would function as well. Lever 30 is pivoted on a shaft 28 rigidly held in a boss 2'l'formed at the upper end of supporting fin 26 of casting 20.

Lever 30 has a downward arm 32, on which roller 33 is mounted, and a horizontal arm 3| which is coupled to needle bar 40, bya link 35.

Link 35 has two clamp portions, 35a and 350. Clamp portion 35a is mounted to move freely on a stud 36, by means of a set screw 35b. Clamp portion 350 is mounted to move freely on a stud 31 by means of a set screw 35d.

Stud 36 is fastened through the end of arm 32 by a threaded portion which receives a nut 36a. Stud 31 is an integral part of needle bar clamp 38, which is fastened on needle bar by a set screw 39. V

The usual feed means, looping means and cutting means are in the bed of the machine. They are not shown because they are made in accordance with conventional practice, and are well known in the art, such as, for example, of the type shown in the patent to R. H. Bradwell, No. 2,104,634, dated January 4, 1938.

The new machine operates as follows:

When power is applied to armshaft I3 through the usual flywheel II and belt I2 arrangement from a suitable power source, the feed, looping and cutting mechanisms in the base of the machine operate in the normal manner in conjunction with the rotation of armshaft I3.

However, the needle bar 40 will only operate as follows:

The rotation of armshaft [3 causes the worm I4, to drive gear I6. Shaft I9 is thereby caused to impart a rotary motion to cam disk 22.

Assuming the position of the parts as shown in Fig. 3, and that such application'of power results in a clockwise rotation of cam disk 22, then lever 30 remains stationary until lobe A on cam disk 22 is reached.

When slope AI of lobe A is reached, roller 33 on arm 32 of needle bar actuating lever 30, is guided by the sidewalls of groove 25 inwardly toward the center of cam disk 22. Arm 32 is then moved toward the. center of cam disk 22. This motion translated about the pivot 28, becomes a down: ward motion of arm 3|. This in turn causes needle bar 40, through the link 35 to move downwardly. The needle carrying the thread then passes through the work, the thread is engaged by the looper and held in the manner well known to the art.

As roller 33 is guided upwardly away from the center of the cam disk 22 by slope A2 of lobe A, arm 32 moves away from the center of cam disk 22. This motion translated about pivot 28, becomes an upward motion of arm 3I. Needle bar 40 is then drawn upwardly, and the needle is withdrawn from the work.

The cutting mechanism, which as herebefore mentioned co-acts with the needle bar action in the conventional manner, then operates. The work is then advanced by the usual action of the dogs and the presser foot, and is then in position for the next stitch.

As cam disk 22 continues to rotate and slopes BI, B2, CI, C2, DI and D2, successively reach and guide roller 33, further stitches are formed.

' lobes A, B, C and D, the needle is caused to enter and be withdrawn fronithe sulting in four stitches.

The number of lobes will then determine the number of stitches formed. By varying the numwork four times, re-

ber of lobes, a variation in the number of stitches,

is obtained; Various cam disks 22 with various numbers of lobes can then be used to give varying numbers of stitches in each tufting group. .as desired. I

When the extreme end of slope D2 of lobe D is reached, roller 33 will be guided into th concentric portion of path 25. The various parts are so proportioned and arranged that when roller 33 ,on arm 32 is in the concentric portion of path 25,

the needle bar will be in the elevated position, and

the needle will be withdrawn from the work. The work will then be free to be moved.

Since the lobes on the cam disk 22 control the switching action of needle bar 40, no further;-

stitches will be formed until that portion of pat 25 which is displaced by the lobes again reaches cam follower 33.

Since only the action of the needle bar has been disturbed by the application of my invention, it is obvious that the operation of the looper and cutter is normal, and likewise the operation of the work feeding means is normal.

In this connection, it is obvious that the worm I4 and the gear I6 must be properly proportioned, and cam disk 22 so designed that the action of the needle bar co-acts in the desired relationship,

' with the action of the looper, cutter and feed means.

The spacing between the groups of stitches results from the fact that whil the cam follower roller 33 is in the concentric portion of the path 25, and no stitches are being formed, the work feed means, consisting of the usual dogs and presser foot arrangement, continues to advance the work, regardless of whether or not, stitches are being formed.

Thus, by simply varying the extent of travel of the feed dogs on each feed cycle by the usual means found on the machine, the spacing between the tufts is changed. When the machine is adjusted as for a fine stitch, the extent of travel of the feed dogs is small, and the work is advanced only a small amount. .When adjusted as for a coarse stitch, the extent of travel of the feed dogs is much greater, and the work is advanced a greater distance on each feed cycle.

The spacing between the tufts is also controlled by the design of the cam 'disk 22, as'it is a function of the relationship between the concentric and displaced portions of the path 25. Thus by varying the number of lobes, on the cam disk 22, the ratio between the concentric and displaced portions is varied, and as the concentric portion increases, the spacing of the tufts increases, and vice versa.

The number of lobes on cam disk 22 is a matter of choice. By providing different cam disks with difierent numbers of lobes, it is possible to vary the number of stitches in each tufting group.

Hence it is also possible, by providing cam disk untrained operator. The absence of springs, clutches, pin latches or other parts which must vbe critically fitted together, makes the substitumounted within said hollowarm and in which a needle bar is supported in said head for reciprocal movement-that improvement which comprises providing a second shaft rotatably supported by said hollow arm, a cam disc mounted on said second shaft for rotation therewith, a lever pivotally supported by said hollow arm, the pivot of which is located between the ends of said lever, a cam follower fixed to said lever adjacent one end thereof and cooperatively engaging said cam disc, means for interconnecting the opposite end of said lever with said needle bar so that rotational movement of said cam disc will directly control the movement of said needle bar, and means for driving said second shaft from said armshaft.

2. A sewing machine according to claim 1 in which the said last named means for driving the second shaft from the armshaft comprises a worm gear fixed to said armshaft and a gear fixed to said second shaft and cooperating with said worm gear.

3. A sewing machine according to claim 1 in which the said cam disc is removably mounted on said second shaft and disposed externally of said hollow arm so that it may be readily accessible for removal and replacement.

4. In a sewing machine of the class described having a head and a hollow arm, and wherein a horizontally disposed armshaft is rotatably mounted within said hollow arm and in which a needle bar is supported in said head for reciprocal movement-that improvement which comprises, a bearing member attached to said hollow arm, a second shaft journaled in said bearing member, a cam disc mounted on said second shaft for rotation therewith, a lever pivotally mounted on said bearing member by a pivot located between the ends of said lever, a cam follower fixed to said lever adjacent one end thereof and cooperatively engaging said cam disc, means for interconnecting the other end of said lever with said needle bar so that rotational movement of said cam disc will directly control the movement -of said needle bar, and means for driving said second shaft from said armshaft.

5. A sewing machine according to claim 4 in which the said second shaft is disposed substantially at right angles to said armshaft.

6. A sewing machine according to claim 4 in which the said cam disc is removably mounted on said second shaft and disposed externally of said bearing member so that it may be readily accessible for removal and replacement.

'1. A sewing machine according to claim 5 in which the said cam disc comprises a concentric portion for maintaining said needle bar stationary for a predetermined period and at least one relatively sharply indented portion designed to cause reciprocal movement of said needle bar.

VICTOR J. SIGODA.

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