US2892426A - Sewing machine attachment - Google Patents

Sewing machine attachment Download PDF

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US2892426A
US2892426A US621044A US62104456A US2892426A US 2892426 A US2892426 A US 2892426A US 621044 A US621044 A US 621044A US 62104456 A US62104456 A US 62104456A US 2892426 A US2892426 A US 2892426A
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sewing machine
cam
sewing
attachment
pressure foot
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US621044A
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Jr Earl L Doster
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    • DTEXTILES; PAPER
    • D05SEWING; EMBROIDERING; TUFTING
    • D05BSEWING
    • D05B21/00Sewing machines with devices for automatically controlling movement of work-carrier relative to stitch-forming mechanism in order to obtain particular configuration of seam, e.g. programme-controlled for sewing collars, for attaching pockets

Description

Julie 30, 1959 E. DOSTER, JR I 2,89%426' 4 SEWING MACHINE ATTACHMENT Filed Nov. 8, 1956 5 Sheets-Sheet l Fig.
Earl L. Dos/er Jr,
INVENTOR.
E.- L. DOSTER, JR 2,892,426
SEWING MACHINE ATTACHMENT June 30, 1959 Filed NOV. 8, 1956 5 Sheets-Sheet 2 L Earl L. Dosfer Jr.
INIf'ENTOR 116m, Em
E. L. DOSTER, JR 2,892,426
- SEWING MACHINE ATTACHMENT June 30, 19 v 5 sheets t 3 Filed Nov. 8, 195
NS m5 ms Earl L. Dos/er, Jr. INVENTOR.
. BY MMEMR I June 30, 1959 E L, DOSTER, JR 2,892,426
SEWING MACHINE ATTACHMENT Filed Nov. 8,1956 5 Sheets-Sheet 4 Fig. /3 Fig. /4
Fig.6
I I I I I 2 Earl L. Oosfer Jr. l2 INVENTOR.
Jime 30, 195 E. L. DOSTER, JR
SEWING MACHINE ATTACHMENT Filed Nov. 8, 1956 5 Sheets-Sheet 5 tu Emu Q SK . JR r m Qv 8 0 I 0 4 y l WM MM,
United States Patent 2,892,426 SEWING MACHINE ATTACHMENT Earl L. Duster; Jr.-, Bremen,- Ga;
Application November 8, 1956,Serial No; 621,044 3 Claims. (Cl. 112 2) This invention relates in general to new and useful improvements in sewing machines, and more specifically to an attachment for sewing machines to facilitate the sewing of lapels and collars.
The primary object of this invention is to provide an attachment for sewing machines which is of such a nature whereby a lapel or collar forming material may be placed upon the work supporting plate or throat plate of a sewing machine and clamped in place by the pressure foot with the machine then automaticallysewing together the material with the stitching formed by the machine being in the outline desired for the lapel or collar.
Another object of this invention is to provide an improved sewingmachine for the sewing of lapels and collars automatically, the sewing machine being provided with a throat plate, a pressure foot and an aligning guide which are so configurated whereby once the material to be sewn is placed relative to the machine, the machine will automatically sew the desired contour of the collar or lapel, the sewing machine being provided with suitable cammed drive-means for moving the material together with the throat plate, the pressure foot and the aligning guide relative to the needle of the sewing machine in the desired path.
Another object of this invention is to provide an improved attachment for sewing machines, the attachment being specifically designed for the sewing of collars and lapels, the attachment including a throat plate having an opening therein corresponding to the desired finished shape of the collar or lapel, a pressure foot for holding the material to be sewed in position relative to the throat plate, and an aligning guide, the aligning guide being of a configuration corresponding to the final shape of collar or lapel and being of such a nature whereby the material to be sewn may be accurately positioned relative to the throat plate by utilizing the aligning guide even though the needle slot in the throat plate will be completely hidden by the material.
Still another object of this invention is to provide an attachment for sewing machines of the type which permits the feedingofmaterial being sewed in both longitudinal and transverse directions; the attachment being specifically designed for sewing collars and lapels and includinga special throat plate, a special pressure foot and an aligniiig guide, the pressure foot and the aligning guide being vertically movably carried by the clamp arm of the sewing machine and there being provided suitable lift means connected to the pressure foot and the aligning guide, whereby" the aligning guide may be first lowered onto the material to besewn to assure theaccurate posi tioning of the material before it is engaged and clamped against the throat plate, by the pressure foot.
A still further object of'this invention is to further provide an attachment for sewing machines of the type which moves the material to be sewn in both longitudinal and transverse directions relative to the needle of the sewing machine, the attachment being specifically designed for the sewing of collars and la els, the attachment including a special cam, a special throat plate, a special 2,892,426 Fatented June 30, 1959 pressure foot and a special aligning gauge, all of the components of the attachment being readily securable to an existing sewing machine.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction'and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:
Figure 1 is an elevational view of a conventional type of sewing machine on which there is mounted the attachment which is the subject of this invention, a general outline of the surface of the cam for providing transverse movement of the attachment being shown;
Figure 2 is a rear elevational view of the sewing machine of Figure l and shows further the details of the relationship between the sewing machine and the attachment, there also being shown a portion of the opposite face of the cam;
Figure 3 is an enlarged fragmentary horizontal sectional view showing the specific outline of the special throat plate and the relationship thereof with respect to the slide plate of the sewing machine;
Figure 4 is an enlarged fragmentary perspective view ofthe head end of the sewing machine and shows the specific details of the throat plate, the pressure foot, the aligning gauge, the needle bar of the sewing machine and lift means for the pressure foot and aligning gauge;
Figure 5 is an enlarged fragmentary vertical sectional view taken substantially upon the plane indicated by the section line 55 of Figure 1 and shows the specific mounting of support arms for the pressure foot and the aligning gauge and the relationship of the lift means with respect thereto;
Figure 6 is an enlarged fragmentary bottom plan view of a bed plate and shows the details of the linkage for effecting transverse sliding movement of the slide plate;
Figure 7 is an enlarged fragmentary plan view of the throat plate and shows the specific shape of the needle slot formed therein;
Figure 8 is a vertical sectional view taken through the cam member removed from the shaft and shows the arrangement of the cam grooves in the opposite faces thereof;
Figure 9 is an elevational view of the inner face of the cam and shows the follower for the inner cam groove in a rearmost position;
Figure 10 is a view similar torFigure 9 and shows the cam rotated to advance the follower for the inner cam groove to advance the slide plate;
Figure 11 is an elevational view of the outer surface of the cam and shows the relationship of the outer cam groove with respect to the follower in an initial position;
Figure 12 is a view similar to Figure ll and shows the cam rotated the same amount as illustrated in Figure 10;
Figure 13 is a reduced fragmentary perspective view of a coat showing the general appearance of the lapel and collar thereof; and
Figure 14 is an enlarged fragmentaiy plan view of a cloth which forms the lapel and collar showing the stitching therein formed by the attachment.
Referring now to the drawings in detail, it will be seen that there is illustrated a sewing machine which is referred to in general by the reference numeral 10. The sewing machine 10 is of a conventional type and is sold commercially as Singer model No. 68-38. The general details of this machine are disclosed in the patent to Barron, Patent No. 1,194,588 issuedAugust 15, 1916, and tlie' patent to Allen, Patent No. 1,537,155 issued May 12,1925. I v
The sewing machine 10 includes the usual bed "plate 12 which is suitably mounted in a supporting base 14.
Secured to the bed plate 12 at one end thereof is the usual bracket arm 16. Carried by the bed plate 12 and the bracket arm 16 is the usual operating mechanism of the sewing machine.
The bracket arm 16 supports at its free end a head 18 in which there is mounted for vertical movement a reciprocating needle bar 20 which carries a removable needle 22 in its lower end. Also carried by the head 18 for vertical movement is a lift bar 24. The function of the lift bar 24 will be set forth in more detail hereinafter.
The main driving shaft (not shown) of the sewing machine is provided with tight and loose pulleys 26 and 28 at its rear end over which runs a belt (not shown) controlled by the usual belt shipper 30. The belt shipper 30 is carried by a stop motion lever 32 which is pivotally mounted as at 34.
Some machines of this type are provided with a transverse shaft 36 on which there is removably mounted a cam or feed wheel 38. The cam 38 has a groove 40 in its inner face and a similar, but different groove 42 in its outer face. The inner groove 40 customarily actuates a suitable follower lever 44 which through the usual connections impart longitudinal motion to a slide bar 46 which rests upon the bed plate 12. The outer groove 42 customarily actuates a suitable follower lever 48 which through linkage 50 imparts transverse components of motion to the slide plate 46.
Carried by the slide plate 46 is a clamp arm 52 which includes a base portion 54 rigidly secured to the slide plate 46, a longitudinally extending free arm portion 56 which overlies the slide plate 46 and a head 58.
The head 58 of the clamp arm 52 is provided with a vertically extending recess 60 which opens through both the upper and lower ends of the head 58 and through that end of the head 58 remote from the clamp arm 52. This will be considered the forward end of the head 58. Secured to the forward end of the head 58 is a cover plate 62 which is removably secured in place by a plurality of fasteners 64.
Slidably disposed in the recess 64 for guided vertical movement between the head 58 and the cover plate 62 are first and second support arms 66 and 68. Formed in the cover plate 62 in alignment with the first support arm is a vertical opening 70 in which there is disposed a lifting lug 72 which is secured to the support arm 68 intermediate its ends. Also formed in the cover plate 62 is an elongated opening 74 which is disposed parallel to the length of the support arm 66. Disposed in the opening 74 is a lifting lug 76 which is secured to the support arm 66. It is to be noted that the openings 70 and '74 have their upper ends disposed in the same plane, but that the ppening 74 extends a considerable distance below the opening 70.
Removably secured to the support arm 66 is a'pressure foot 78. The pressure foot 78 having an upwardly and rearwardly sloping portion 80 which underlies a downwardly and forwardly sloping portion 82 of the support arm 66. A fastener 84 passes through the portions 88 and 82 to secure the two together. The portion 82 is carried from the vertical part of the support arm 66 by a forwardly extending horizontal portion 86.
The support arm 68 includes a horizontal forwardly extending portion 88 which terminates in a downwardly forwardly sloping portion 90. Underlying the portion 90 is an upwardly sloping portion 92 of an aligning guide 84. The aligning guide 94 is secured to the support arm 68 by means of a fastener 96. It is to be noted that the aligning guide 94 cooperates with the pressure foot 78 to define an elongated slot 98 which is generally the outline of the stitching to be sewn,
Secured to the forward portion of the slide plate 46 by means of a pin 100 is a slide block 102 which is illustrated 1n Figure 6. The slide block 102 is connected to the linkage 50 for effecting IIansYQ QQ mo ent of the slide plate 46. Extending upwardly through the slide block 102 on opposite sides of the forward part of the slide plate 46 are fasteners 104. The fasteners 104 pass through rear portions of a throat plate 106.
As is best illustrated in Figures 3 and 7, the forward part of the throat plate 106 is provided with a needle slot 108. The needle slot 108 includes a straight longitudinal portion 110 and a forwardmost angulated portion 112. In order to facilitate the gripping of the material to be sewn, that portion of the upper surface of the throat plate 106 surrounding the needle slot 110 is scored as at 114.
In order that both the pressure foot 78 and the aligning guide 94 may be retained in a cloth clamping position relative to the throat plate 106, there is carried by the clamp arm 52 a pair of springs 116 and 118. The springs 116 and 118 are identical and differ from each other only in that the spring 118 acts on the aligning guide 94 through the support arm 68 whereas the spring 116 acts on the pressure foot 78 through the support arm 66. The upper ends of the support arms 66 and 68 are provided with notches 120 and 122, respectively, receiving the forward ends of the springs 116 and 118.
The upper rear part of the clamp arm 52 is provided with a horizontally disposed rest 124. The rest 124 has disposed thereon the rear end of the springs 116 and 118. Carried by the clamp arm 52 forwardly of the rest 124 is a fitting 126 carrying a pair of adjusting screws 128, there being one adjusting screw 128 for each of the springs 116 and 118. By moving the individual adjusting screws 128 up or down, the tension of the springs 116 and 118 may be varied. It is to be noted that each of the springs 116 and 118 is provided with an intermediate loop portion 130 to increase the tension thereof.
Carried by the intermediate part of the bracket arm 16 is a fitting 132 which carries a transverse stud 134 on which there is pivotally mounted a longitudinally extending rock lever 136. Connected to the rear end of the rock lever 136 is a flexible member 138 whose lower end is connected to a foot treadle (not shown). The forward end of the rock lever 136 is connected to the upper end of the lift bar 24 so that when the flexible member 138 is tensioned, the lift bar 24 is moved upwardly through the head 18.
Secured to the upper part of the lift bar 24 above its connection with the rock lever 136 is a lift arm 140. The lift arm 140 extends outwardly and rearwardly from the lift bar 24 and has connected thereto a depending lift rod 142. The lower end of the lift rod 142 is secured to a rear part of the lower lift arm 144. The forward part of the lower lift arm 144 is connected to thelower end of the lift bar 24 by means of a fitting 146 adjustably mounted on the lift bar 24.
Secured to the lifting lug or ear 76 is a transverse bar 148, the bar 148 being removably secured to the lifting lug 76 by means of a fastener 150. The transverse bar 148 has one end thereof directly overlying the lower lift arm 144. The opposite end of the transverse bar 148 is disposed in underlying relation with respect to the lifting lug 72.
Referring now to Figures 9 and 10, it will be seen that there is shown the relationship of a follower 152 carried by the follower lever 44 with respect to the cam groove 40. In the initial position of the cam 38 and the follower 152, the follower 152 is disposed in a rearwardmost posi tion. As' the cam 38 begins to rotate, the follower 152 follows the outline of the cam groove 40 and is advanced forwardly. This results in the pivoting of the follower member 44 and because of its connection with the slide plate 46, the slide plate 46 is pulled rearwardly. It is to be noted that the rearward movement of the slide plate 46 continues for a half of a revolution of the cam 38. v
Referring now to Figures 11 and 12 in particular, it will be seen that there is illustrated the relationship be tween the cam groove 42 and a follower 154 carried by the follower lever s; In its initial position; the follower 154 is in a forwaidmost position and as the cam 38 starts to rotate, it remains stationary for a period of time due to the fact that the cam groove 42 is concentric with the axis of the cam 38 tlu'ri'ng the initial part of its travel with respect to the follower 154-. It is to be noted that the movement of the follower 154 is a rearward one and that after the cam 38. has rotated 180 degrees, motion of the follower 154 is reversed.
The cam grooves 40 and 42 are so shaped whereby the followers 152 and 154 will effect movement of the throat plate 106 in a path defined by the needle slot 108 so that the throat plate 106 and the material clamped thereto will move relative to the needle 22 so as to retain the needle 22 within the needle slot 108 at all times during the sewing operation. This is accomplished by synchronizing the cam grooves 40 and 42 when the cam 38 is fashioned. During the initial rotation of the cam 38, as pointed out above, the follower 152 is moved to move the throat plate 106 rearwardly. At the same time, the follower 154 remains stationary. After the cam 38 has rotated approximately 110, then the follower 154 is moved rearwardly and since the follower 154 efiects the transverse position of the throat plate 106, it will be seen that the throat plate 106 is moved transversely. At the same time, the follower 152 is moving the throat plate 106 rearwardly so that the actual movement of the throat plate 106 is rearwardly and to one side to effect angulated movement corresponding to the angulated portion 112 of the needle slot 108.
Referring now to Figure 13, it will be seen that there is illustrated a mans coat 156. The man's coat 156 includes a lapel 158 and a collar 160. It is the purpose of the attachment which is the subject of this invention to automatically shape to the lapel 158 at its connection with the collar 160. This is accomplished by taking the pieces of cloth 162 which are used to form the lapel 158 or collar 160 and sewing them together by stitching 164 of a desired pattern. It is to be noted that the outline of the needle slot 108 corresponds to the pattern of the stitching 164.
In the operation of the present invention, the pieces of material 162 are disposed in their desired overlying relation and then are placed on the throat plate 106 in the approximate position for sewing. Next the foot treadle (not shown) is released and permit downward movement of the lift bar 24. When the pressure foot 78 and the aligning gauge 94 are in elevated positions, the aligning gauge 94 is disposed below the level of pressure foot 78. Thus as the lift bar 24 moves downwardly, the aligning gauge 94 moves downwardly in advance of the pressure foot 78. By permitting the aligning gauge 94 to lightly engage the material 162 and then shifting the mater al 162 to align it with the aligning gauge 94. The material 162 may be accurately positioned for sewing. After this has been accomplished, the aligning gauge 94 and the pressure foot 78 are continued to be lowered by lowering the lift bar 24. In their lowermost positions, the pressure foot 78 and the aligning gauge 94 will clamp the material 162 against the throat plate 106 due to the urging of the springs 116 and 118. Inasmuch as the material 162 will be clamped against the throat plate 106 by the pressure foot 78 as well as the aligning gauge 94, it will be seen that during a sewing operation the material 102 will move together with the pressure foot 78, the aligning gauge 94 and the throat plate 106 as a unit.
After the material 162 has been properly positioned with respect to the sewing machine, it is merely necessary to operate the sewingfmachine in the conventional manner and as a result the stitching 164 will be sewn by the needle 22. If desired, the stitching 164 may be double by merely permitting the cam 38 to travel one entire revolution. On the other hand, if it is merely desired to single stitch the lapel or collar, two lapels or collars maybe sewed with a single revolution of the cam 38. The first lapel is placedin position and the machine i's operated so that the necessary stitching'is formed. The collar is then removed and replaced by a second collar with the position of the collar being determined by the aligning-guide. The cam 38 continues to rotate in a relative travel between the thsoat plate and the needle is reversed.
Normally there will be provided four separate machines for sewing collars and lapels, one machine will sew a right hand collar and the other machine will sew a left hand collar, a third machine will sew a right hand lapel and a fourth machine will sew a left hand lapel. Should the collar and lapel be of the same configuration, one machine may sew both collar and lapel. Also, one machine may sew both left and right collars and lapels by merely turning the material over when it is being sewed.
It is to be understood that with minor adaptations the sewing machine, which is the subject of this invention, may be used for sewing other parts of clothing which have curved contours. For example, in the fly of a troruser at the lower part thereof is a sitching which is curved similar to the curve of a lapel or collar end. Such a curve may be sewn utilizing a slightly modified form of attachment.
It is to be understood that the attachments which are the subject of this invention may be readily placed on existing sewing machines of the model previously described with only minor changes in the construction of the sewing machine and once the attachments have been placed on the sewing machine, the sewing machine willfunction in its normal manner with the exception of the pattern of the stitching sewn. Also, the attachment may be removed from the sewing machine when desired and the sewing machine re-converted to its original purpose.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous m0- difications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.
What is claimed as new is as follows:
1. In combination with a sewing machine of the type including a slide plate, a clamp arm carried by said slide plate, a needle bar, and a lift bar, a lapel sewing attachment comprising a work supporting plate, means securing said Work supporting plate to said slide plate, said work supporting plate having a needle slot, said needle slot having the outline of a lapel to be sewn, a support fitting on saidclamp arm, a first support arm carried by said support fitting for vertical sliding movement, a second support arm carried by said support fitting for vertical sliding movement, a pressure foot carried by said first support arm for clamping cooperation with said work supporting plate, a cloth aligning gauge carried by said second support arm, spring means carried by said clamp arm for urging said pressure foot and said aligning gauge towards said work supporting plate, cam means connected to said slide plate for moving said work supporting plate, said pressure foot and said aligning gauge relative to said needle bar in a path defined by said needle slot, and lift means connecting said lift bar to said support arms for first lifting said pressure foot and then lifting said aligning gauge whereby said aligning gauge may be used to align a lapel to be sewn prior to engagement thereof by said pressure foot, said pressure foot and said aligning gauge having opposed complementary edges defining a needle opening corresponding to the shape of said needle slot.
2. The lapel sewing attachment of claim 1 wherein said lift means includes a lift arm secured to said lift bar, a lift car on each of said support arms, said lift ear of said first upper ends'of said support arms, said spring means having separate tensioning means for said spring members.
. References Cited-in the file of this patent UNITED STATES PATENTS Workman Oct. 8, 1935 Giancola May 13, 1941 Gunther Feb. 8, 1944
US621044A 1956-11-08 1956-11-08 Sewing machine attachment Expired - Lifetime US2892426A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3221689A (en) * 1961-11-24 1965-12-07 James Paul Leo Method of sewing elastic stitches

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2016354A (en) * 1934-07-09 1935-10-08 Walter J Workman Sewing machine
US2241778A (en) * 1939-06-02 1941-05-13 Giancola Nicholas Presser foot and multiple gauge for sewing machines
US2341441A (en) * 1942-08-15 1944-02-08 Singer Mfg Co Work holder for article-attaching machines

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2016354A (en) * 1934-07-09 1935-10-08 Walter J Workman Sewing machine
US2241778A (en) * 1939-06-02 1941-05-13 Giancola Nicholas Presser foot and multiple gauge for sewing machines
US2341441A (en) * 1942-08-15 1944-02-08 Singer Mfg Co Work holder for article-attaching machines

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3221689A (en) * 1961-11-24 1965-12-07 James Paul Leo Method of sewing elastic stitches

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