Fabric clamp adapted to pass under presser foot of sewing machine

10563331 ยท 2020-02-18

Assignee

Inventors

Cpc classification

International classification

Abstract

A fabric clamp that passes under the presser foot of a sewing machine is provided. The clamp has a loop of resilient strip folded over upon itself, an upper slotted lever, and a lower slotted lever. The resilient strip has an upper portion, the terminus of which defines an upper planar jaw, and a generally planar lower portion, the terminus of which defines a lower planar tongue, joined by a curvilinear central portion. The upper portion of the resilient strip passes through the upper lever. The lower portion of the resilient strip passes through the lower lever. The total transverse width of the portions of the tongue is no more than about 12 mm. The curvilinear portion urges the jaw and tongue together. When the upper jaw and the tongue are adjacent and the levers are urged together, the jaw and the tongue are displaced from adjacent deployment.

Claims

1. A fabric clamp adapted to pass under a presser foot of a sewing machine, comprising: a loop of resilient strip folded over upon itself, defining: an upper portion; and a generally planar lower portion; said upper portion and said generally planar lower portion being joined by a curvilinear central portion; an upper slotted lever; a lower slotted lever; a terminus of said upper portion being generally planar and defining an upper planar jaw joined to said curvilinear central portion through an obtuse oblique; a terminus of said generally planar lower portion of said loop of resilient strip defining a lower planar tongue, said curvilinear central portion urging said jaw and said tongue into adjacent deployment; wherein said upper portion of said resilient strip passes through said upper slotted lever such that the upper slotted lever engages a lower surface of said upper portion of said resilient strip at a location along said obtuse oblique and engages other surface of said resilient strip at a location between said lower portion of said resilient strip and a location corresponding to that at which said upper lever engages the lower surface of said upper portion, said upper lever extending past said curvilinear portion; and wherein said lower portion of said resilient strip passes through said lower slotted lever, said lower lever engaging an upper surface of said lower portion of said resilient strip between said curvilinear portion and said terminus of said generally planar lower portion, said lower slotted lever extending past said curvilinear portion, said upper slotted lever and said lower slotted lever bearing against each other along a transversely extending area between said curvilinear portion of said resilient strip and said obtuse oblique; portions of said upper lever and said lower lever extending beyond said curvilinear portion being spaced apart when said upper planar jaw and said lower planar tongue are in the adjacent deployment and said levers being urgable together against a resilience of said curvilinear central portion to displace said jaw and said tongue from the adjacent deployment; wherein a total transverse width of portions of said tongue on said lower portion is no more than about 12 mm.

2. The fabric clamp of claim 1, wherein said resilient strip comprises stainless alloy comprising iron and chromium having a thickness of between about 0.25 mm and 1.5 mm.

3. The fabric clamp of claim 2, wherein said tongue is a solid tongue with the transverse width of said tongue on said lower portion is no more than about 3.5 mm.

4. The fabric clamp of claim 3, wherein the transverse width of said tongue on said lower portion is no more than about 2.5 mm.

5. The fabric clamp of claim 2, wherein said tongue has an aperture formed therein having a width of at least about 1.5 mm and wherein said aperture is laterally bounded by arms having a width of no more than about 4 mm.

6. The fabric clamp of claim 5, wherein the width of said aperture is at least about 2 mm.

7. The fabric clamp of claim 5, wherein said resilient strip comprises stainless alloy comprising iron and chromium having a thickness of between about 0.35 mm and 1.5 mm.

8. A fabric clamp adapted to pass under a presser foot of a sewing machine, comprising: a loop of resilient strip comprising stainless steel having a thickness of between about 0.25 mm and 1.5 mm folded over upon itself, defining: an upper portion; and a generally planar lower portion; said upper portion and said generally planar lower portion being joined by a curvilinear central portion; an upper slotted lever; a lower slotted lever; a terminus of said upper portion being generally planar and defining an upper planar jaw joined to said curvilinear central portion through an obtuse oblique, said upper planar jaw comprising a frame circumscribing a central aperture; a terminus of said generally planar lower portion of said loop of resilient strip defining a lower planar tongue having lateral arms a defining an aperture formed therein, wherein a transverse width of said aperture is at least about 1.5 mm, and a width of each of the lateral arms is no more than about 4 mm; said curvilinear central portion urging said jaw and said tongue into interjacent generally coplanar deployment with said tongue disposed in said central aperture; wherein said upper portion of said resilient strip passes through said upper slotted lever such that the upper slotted lever engages a lower surface of said upper portion of said resilient strip at a location along said obtuse oblique and engages other surface of said resilient strip at a location between said lower portion of said resilient strip and a location corresponding to that at which said upper lever engages the lower surface of said upper portion, said upper lever extending past said curvilinear portion; wherein said lower portion of said resilient strip passes through said lower slotted lever, said lower lever engaging an upper surface of said lower portion of said resilient strip between said curvilinear portion and said terminus of said generally planar lower portion, said lower slotted lever extending past said curvilinear portion, said upper lever and said lower lever bearing against each other along a transversely extending area between said curvilinear portion of said resilient strip and said obtuse oblique; portions of said upper lever and said lower lever extending beyond said curvilinear portion being spaced apart when said upper planar jaw and said lower planar tongue are in the interjacent generally coplanar deployment and said levers being urgable together against a resilience of said curvilinear central portion to displace said jaw and said tongue from the interjacent generally coplanar deployment.

9. The fabric clamp of claim 8, wherein alignment protrusions are provided on one of said slotted levers, and alignment recesses, mateable therewith, are provided on other of said slotted levers and wherein said resilient strip comprises stainless steel comprising iron and chromium having a thickness of between about 0.35 mm and 1.5 mm.

10. A fabric clamp adapted to pass under a presser foot of a sewing machine, comprising: a loop of resilient strip having a thickness of between about 0.25 mm and 1.5 mm comprising an alloy of iron and chromium folded over upon itself, defining: an upper portion; and a generally planar lower portion; said upper portion and said generally planar lower portion being joined by a curvilinear central portion; a terminus of said upper portion being generally planar and defining an upper planar jaw joined to said curvilinear central portion through an obtuse oblique, said upper planar jaw comprising a frame circumscribing an aperture; a terminus of said generally planar lower portion of said loop of resilient strip defining a lower planar tongue, said curvilinear central portion urging said jaw and said tongue into interjacent generally coplanar deployment with said tongue disposed in said aperture; an upper slotted lever; a lower slotted lever; wherein said upper portion of said resilient strip passes through said upper slotted lever, engaging a lower surface of said upper portion of said resilient strip at a location along said obtuse oblique and engaging other surface of said resilient strip at a location between said lower portion of said resilient strip and a location corresponding to that at which said upper lever engages the lower surface of said upper portion, said upper lever extending past said curvilinear portion; and wherein said lower portion of said resilient strip passes through said lower slotted lever, said lower lever engaging an upper surface of said lower portion of said resilient strip between said curvilinear portion and said terminus of said generally planar lower portion, said lower slotted lever extending past said curvilinear portion, said upper lever and said lower lever bearing against each other along a transversely extending area between said curvilinear portion of said resilient strip and said obtuse oblique; portions of said upper lever and said lower lever extending beyond said curvilinear portion being spaced apart when said upper planar jaw and said lower planar tongue are in the interjacent generally coplanar deployment and said levers being urgable together against a resilience of said curvilinear central portion to displace said jaw and said tongue from the interjacent generally coplanar deployment; and wherein when said clamp is deployed with layers of fabric between the upper planar jaw and said lower planar tongue thereof, no single portion of the lower tongue disposed below said fabric has a transverse width exceeding 5 mm and wherein each portion of the lower tongue disposed below said fabric is laterally separated from every other portion of said jaw by a distance of at least about 1.5 mm.

11. The fabric clamp of claim 10 wherein an aperture bounded by lateral arms is formed in said tongue, said aperture having a transverse width of at least about 1.5 mm, each said lateral arm having a transverse width of no more than about 5 mm and wherein said resilient strip comprises stainless steel comprising iron and chromium having a thickness of between about 0.35 mm and 1.5 mm.

12. The fabric clamp of claim 10 wherein an aperture bounded by lateral arms is formed in said tongue, said aperture having a transverse width of at least about 2 mm, each said lateral arm having a transverse width of no more than about 4 mm and wherein said resilient strip comprises stainless steel comprising iron and chromium having a thickness of between about 0.35 mm and 1.5 mm.

13. The fabric clamp of claim 10 wherein an aperture bounded by lateral arms is formed in said tongue, said aperture having a transverse width of at least about 3.5 mm, each said lateral arm having a transverse width of no more than about 3.5 mm and wherein said resilient strip comprises stainless steel comprising iron and chromium having a thickness of between about 0.35 mm and 1.5 mm.

14. The fabric clamp of claim 10 wherein an aperture bounded by lateral arms is formed in said tongue, said aperture having a transverse width of at least about 2.5 mm, each said lateral arm having a transverse width of no more than about 3 mm and wherein said resilient strip comprises stainless steel comprising iron and chromium having a thickness of between about 0.35 mm and 1.5 mm.

15. A fabric clamp adapted to pass under a presser foot of a sewing machine, comprising: a loop of resilient strip comprising a stainless alloy comprising iron and chromium having a thickness of between about 0.25 and 1.5 mm, said resilient strip being folded over upon itself, defining: an upper portion; and a generally planar lower portion; said upper portion and said generally planar lower portion being joined by a curvilinear central portion; a terminus of said upper portion being generally planar and defining an upper planar jaw joined to said curvilinear central portion through an obtuse oblique, said upper planar jaw comprising a frame circumscribing an aperture; a terminus of said generally planar lower portion of said loop of resilient strip defining a lower planar jaw, said curvilinear central portion urging said upper planar jaw and said lower planar jaw into interjacent generally coplanar deployment with said lower planar jaw disposed in said aperture of said upper planar jaw; said lower planar jaw and said upper planar jaw being urgable apart against a resilience of said curvilinear central portion to displace said upper planar jaw and said lower planar jaw from the interjacent generally coplanar deployment; and wherein when the fabric clamp is disposed grasping an assemblage of fabric with the upper jaw above said assemblage of fabric and the lower jaw beneath said assemblage of fabric, no portion of the jaw beneath said assemblage of fabric has a lateral width of more than 5 mm and each portion of said jaw beneath said assemblage of fabric is laterally separated from every other portion of said jaw beneath said assemblage of fabric by a lateral distance of more than about 1.5 mm.

16. The fabric clamp of claim 15 wherein the portion of said jaw beneath said assemblage of fabric comprises a tongue having a transverse width of no more than about 5 mm and wherein said resilient strip comprises stainless steel having a thickness of between about 0.35 mm and 1.5 mm.

17. The fabric clamp of claim 15 wherein the portion of said jaw beneath said assemblage of fabric comprises a tongue having an aperture formed therein, said aperture being laterally bounded by lateral arms, said aperture having a transverse width of at least about 1.5 mm, each said lateral arm having a transverse width of no more than about 5 mm and wherein said resilient strip comprises stainless steel having a thickness of between about 0.35 mm and 1.5 mm.

18. The fabric clamp of claim 17 wherein the transverse width of said aperture is at least about 2 mm, the transverse width of each said lateral arm is no more than about 4 mm.

19. The fabric clamp of claim 18 wherein the transverse width of said aperture is at least about 3 mm, the transverse width of each said lateral arm is no more than about 3.5 mm and wherein said resilient strip comprises stainless steel having a thickness of between about 0.35 mm and 1.5 mm.

20. A fabric clamp adapted to pass under a presser foot of a sewing machine, comprising: a loop of resilient strip comprising a stainless alloy comprising iron and chromium having a thickness of between about 0.25 and 1.5 mm, said resilient strip being folded over upon itself, defining: an upper portion; and a generally planar lower portion; said upper portion and said generally planar lower portion being joined by a curvilinear central portion; a terminus of said upper portion being generally planar and defining an upper planar jaw joined to said curvilinear central portion through an obtuse oblique; a terminus of said generally planar lower portion of said loop of resilient strip defining a lower planar jaw, said curvilinear central portion urging said upper planar jaw and said lower planar jaw into parallel adjacent deployment; said lower and upper jaw being urgable apart against a resilience of said curvilinear central portion to displace said upper jaw and said lower jaw from the adjacent deployment; and wherein when the fabric clamp is disposed grasping an assemblage of fabric with the upper jaw above said assemblage of fabric and the lower jaw beneath said assemblage of fabric, no portion of the jaw beneath said assemblage of fabric has a lateral width of more than 5 mm and any portion of said jaw beneath said assemblage of fabric which is laterally separated from another portion of said jaw beneath said assemblage of fabric, is laterally separated from every other portion of said jaw beneath said assemblage of fabric by a lateral distance of more than about 1.5 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described in detail below with reference to the appended drawings, wherein like numerals designate similar parts. In the Figures:

(2) FIG. 1 illustrates a clamp of the present invention having plastic levers configured to facilitate separation of the upper and lower jaws of the clamp against the resilience of the steel.

(3) FIGS. 1A-1C schematically illustrate differences between stitches resulting as a clip of the present invention passes under a presser foot, FIG. 1A, as compared to stitches formed as clips not of the present invention pass under a presser foot.

(4) FIG. 1-D schematically illustrates two pieces of fabric joined together by a clip of the present invention.

(5) FIGS. 2 and 3 illustrate a highly preferred configuration of a large clamp of the present invention having levers for forcing the jaws apart wherein the dimensions are chosen such that an assemblage of fabric held together by the clamps of the present invention will pass under presser foot whilst forming a seam of high qualitypreferably without puckers or skipped stitches and most advantageously without jamming.

(6) FIGS. 4 and 5 illustrate highly preferred dimensions for one small clamp of the present invention having a window type of lower jaw. In this case, the levers are not shown but are substantially as shown in FIGS. 2 and 3.

(7) FIGS. 6-9 illustrate the most preferred dimensions for one small clamp of the present invention having a tongue type of lower jaw. In this case, the levers are not shown but are substantially as shown in FIGS. 2 and 3.

(8) FIG. 10 illustrates a clamp of the present invention as shown in FIG. 1 in which the plastic levers configured to facilitate separation of the upper and lower jaws of the clamp against the resilience of the steel have been urged together separating the upper and lower jaws so that fabric may be inserted therebetween and thereafter clamped by removal of the pressure applied to the levers.

(9) FIGS. 11 and 12 illustrate clamps of the present invention having scale markings engraved on the frame of the upper jaw to allow the seamstress to control the width of seams more precisely.

(10) FIG. 13 illustrates a side view of a clamp of the present invention as shown in FIG. 1 in the open position with a phantom view of the upper jaw in the closed position superposed thereover to illustrate the action of the levers and opening and closing the jaw of the clamp.

(11) FIG. 14 illustrates a side view of a clamp of the present invention as shown in FIG. 1 in the closed position to illustrate the extreme thinness of the jaw of the clamp. Note that even though the jaws preferably interpenetrate when closed; in this Figure, they are shown stacked as might be occasioned by relatively stiff fabric therebetween.

(12) FIG. 15 illustrates a clamp of the present invention passing under the presser foot of a sewing machine whilst holding fabric in place for precise formation of a seam.

(13) FIG. 16 illustrates how a multiplicity of clamps may be positioned and left in place during a prolonged period of the sewing process to more conveniently define a complex seam.

(14) FIGS. 17 and 18 illustrate clamping of fabric in the jaws of the clamp of the present invention.

(15) FIGS. 19 and 20 are perspective views illustrating the metal portion of a small clamp of the present invention in which the lower jaw takes the form of a tongue protruding into the window defined by the upper jaw.

(16) FIGS. 21 and 22 are perspective views illustrating the metal portion of a small clamp of the present invention in which the lower jaw takes the form of a window protruding into the window defined by the upper jaw.

(17) FIGS. 23 and 24 are perspective views of the clamp of FIG. 1 with the jaws being urged apart.

(18) FIGS. 25-27 illustrate perspective views of the clamp of FIG. 1 with the jaws being urged together by the resilience of the metal in the U of the clamp.

(19) FIGS. 28, 29 and 30 are perspective views of the levers of the clamp of FIG. 1 illustrating alignment of protrusions with recesses maintaining the proper interrelationship between the levers as well as slots which the resilient stainless steel strip passes through in each, while

(20) FIG. 31 illustrates the gripping ridge on the upper surface of upper lever facilitating grasp upon the upper lever.

(21) FIG. 32 illustrates the gripping recess on the lower surface of lower lever facilitating grasp upon the lower lever.

(22) FIGS. 33-38 are plan view, left elevation, front elevation, lower surface, right elevation and rear elevation views of the upper lever.

(23) FIGS. 39-43 are plan view, front elevation, left elevation, rear elevation, and lower surface views of the lower lever.

(24) FIGS. 44 and 45 are isometric perspectives illustrating an alternative form of the clamp of the present invention not requiring plastic levers.

(25) FIGS. 46 and 47 are schematic illustrations of alternative configurations of the curvilinear portion of the resilient metal strip.

(26) FIGS. 48 and 49 schematically illustrate an alternative construction in which the upper jaw is formed without an aperture therethrough.

DESCRIPTION OF PREFERRED EMBODIMENTS

(27) The invention is described in detail below with reference to several embodiments. Such discussion is for purposes of illustration only. Modifications to particular examples within the spirit and scope of the present invention, set forth in the appended claims, will be readily apparent to one of skill in the art. Terminology used herein is given its ordinary meaning consistent with the exemplary definitions set forth immediately below.

(28) With respect to the various ranges set forth herein, any upper limit recited may, of course, be combined with any lower limit for selected sub-ranges.

(29) The transitional phrase consisting essentially of limits the scope of a claim to the specified materials or steps and those that do not materially affect the basic and novel characteristic(s) of the claimed invention. As used herein, consisting essentially of and like terminology refers to the recited components and excludes other components which would substantially change the basic and novel characteristics of the article. Unless otherwise indicated or readily apparent, an article consists essentially of the recited components when the article includes 90% or more of the recited components. That is, the terminology excludes more than 10% unrecited components.

(30) In FIG. 1, clamp 10 is comprised of a thin sheet 12 of resilient stainless steel having generally planar jaws 14 and 16 formed at either end 18 and 20 of resilient stainless steel sheet 12 with U or portion 22 in between. Normally, I prefer to use a stainless steel strip 12 formed into an configuration as shown in FIG. 46 as this makes a more compact design; but either form of curvilinear portion 22 may be used. Upper portion 24 of said resilient strip 12 passes through slot 26 in upper lever 28 and engages lower surface 30 of upper portion 24 at location 32 between obtuse oblique 34 portion of upper portion 24 and curvilinear portion 22 whilst upper lever 28 engages upper surface 48 of resilient strip 12 at a location 36 between location 32 at which upper lever 28 engages lower surface 30 of upper portion 24 and lower portion 38 of resilient strip 12, upper lever 28 extending past curvilinear portion 22 whilst upper lever 28 and lower lever 40 bear against each other along transversely extending area 42 between curvilinear portion 22 of said resilient strip 12 and obtuse oblique 34; with portions 44 and 46 of upper lever 28 and lower lever 40 respectively extending beyond curvilinear portion 22 being spaced apart when upper jaw 14 and lower jaw 16 are in interjacent generally coplanar deployment and urgable apart against the resilience of curvilinear upper U or portion 22 to displace upper jaw 14 and lower jaw 16 from interjacent generally coplanar engagement. Upper jaw 14 comprises longitudinal arms 47 and 50 joined by header 52 forming window 54 into which lower jaw 16 interpenetrates with window 56 in lower jaw 16 being defined by longitudinally extending arms 58 and 60 joined by header 62.

(31) FIGS. 1A-1C schematically illustrate differences between stitches resulting as a clip of the present invention passes under a presser foot, FIGS. 1A and 1B, as compared to stitches formed as clips not of the present invention pass under a presser foot FIG. 1C. In particular, in fabric 66 three lines 96 of stitches 98 are formed across fabric 66 with each stitch 98 being of substantially the same length and generally collinear with each other. This is possible when the total thickness of jaws 14 and 16 with fabric 66 gripped therebetween is such that clip 10 having dimensions as prescribed herein is able to pass under the presser foot without puckering, slipping or sticking. In contrast in FIG. 1C, line 96 of stitches 98 illustrates the result when fabric 66 either sticksdoes not advance by the usual feed per stitch of the machineand accordingly small, uneven stitches 97 are formed or fabric 66 surgesadvances by more than the usual feed per stitchin which case missed stitch 99 is formed.

(32) FIG. 1D schematically illustrates two pieces of fabric 66 joined together by clip 10 of the present invention grasping fabric 66 between upper jaw 14 and lower jaw 16 concealed in this Figure by fabric 66.

(33) FIGS. 2 and 3 illustrate highly preferred dimensions for large clamp 10 of the present invention having levers 28 and 40 for forcing jaws 14 and 16 apart. Investigations with several popular sewing machines indicate that smooth passage under the presser foot is limited primarily by the maximum width of the portions of the lower jaw interposed between the fabric and the throat plate of the sewing machines. In particular, it appears that when only a single tongue is interposed between the fabric and the throat plate of the sewing machine, smooth passage is highly assured when the width of the tongue is less than about 3.5 mm with passage becoming less certain but still probable as the width of the tongue is increased to 4 mm, and is still less certain at 5 mm and usually becomes problematic as the width of the tongue is increased beyond 6 mm. The best results are obtained when the width of the tongue is about 2.2 mm or less. When the lower jaw takes the form of a frame having lateral sides, similar smooth passage guidelines apply to the width of each arm of the frame whilst excellent results are obtained when the width of the arms are about 2.54 mm or less with best results when the width is about 1.5 mm or less. Even though the same strictures do not apply to the upper jaw and indeed the top jaw can have considerable width without unduly interfering with smooth passage, I greatly prefer the window within a window configuration of FIGS. 2 and 4 or tongue within a window configuration of FIG. 6 as it enables me to reduce the overall height of the assemblage. When the window within a window configuration is used, it is highly advantageous that the width of the window be about 1 mm or more and even better if the width is about 1.5 mm or 2 mm as the feed dogs of the machine have more fabric to grip between the interruption occasioned by the arms of the frame. The width of the aperture may beneficially be increased to 3, 4 or 6 mm or more without interfering with the ability to pass under the presser foot. I prefer the window in window construction as it makes it possible to decrease the height of the assemblage of the jaws and fabric as it passes under the presser while reducing length of interruptions occasioned by the arms of the inner frame while substantially retaining the clamping force that would be occasioned by a single tongue having the combined width of the arms of the frame. Conceptually, of course, the solid tongue in a window configuration is merely a special case of the window within a window configuration wherein the width of the window is nil. Throughout this specification and claims, where the terms lateral and transverse are used, they should be understood to refer to the direction perpendicular to the long axis of the clamp and parallel to the motion of the fabric as it passes under the presser foot of the sewing machine.

(34) FIGS. 4 and 5 illustrate highly preferred dimensions for small clamp 64 of the present invention having window type lower jaw 16. In this case, the levers are not shown but are substantially as shown in FIGS. 2 and 3.

(35) FIGS. 6-9 illustrate the most preferred dimensions for small clamp 64 of the present invention having a tongue type of lower jaw 16. In this case, the levers are not shown but are substantially as shown in FIGS. 1, 2 and 3.

(36) All dimensions in FIGS. 2-9 are shown in millimeters, with the exception of angles measured in degrees, which are accordingly marked (i.e., ).

(37) FIG. 10 illustrates clamp of the present invention 10 as shown in FIG. 1 in which plastic levers 28 and 40 configured to facilitate separation of upper jaw 14 and lower jaw 16 of clamp 10 against the resilience of resilient stainless steel strip 12 have been urged together separating upper jaw 14 and lower jaw 16 so that fabric 66 may be inserted therebetween and thereafter clamped by removal of pressure applied to levers 28 and 40.

(38) FIGS. 11 and 12 illustrate clamps of the present invention 10 having scale markings engraved on longitudinally extending arms 47 and 50 of upper jaw 14 to allow the seamstress to control the width of seams more precisely.

(39) FIG. 13 illustrates a side view of clamp 10 of the present invention as shown in FIG. 1 in the open position with a phantom view of the upper jaw 14 in the closed position superposed thereover to illustrate the action of the levers and opening and closing the jaw of the clamp.

(40) FIG. 14 illustrates a side view of clamp 10 of the present invention as shown in FIG. 1 in the closed position to illustrate the extreme thinness of jaws 14 and 16 of clamp 10. Note that even though jaws 14 and 16 interpenetrate when closed without fabric 66 therebetween, in this FIG. 14 they are shown stacked as might be occasioned by relatively stiff fabric 66 therebetween.

(41) FIG. 15 illustrates clamp 10 of the present invention passing under the presser foot 68 of a sewing machine while holding fabric 66 in place for precise formation of a seam.

(42) FIG. 16 illustrates how a multiplicity of clamps 10 may be positioned and left in place during a prolonged period of the sewing process to more conveniently define a complex seam.

(43) FIGS. 17 and 18 illustrate clamping of fabric 66 in jaws 14 and 16 of clamp 10 of the present invention.

(44) FIGS. 19 and 20 are perspective views illustrating metal sheet 12 of small clamp 64 of the present invention in which lower jaw 16 takes the form of tongue 70 protruding into window 56 defined by upper jaw 14.

(45) FIGS. 21 and 22 are perspective views illustrating metal sheet 12 of small clamp 64 of the present invention in which lower jaw 16 takes the form of window 72 protruding into window 56 defined by upper jaw 14.

(46) FIGS. 23 and 24 are perspective views of clamp 10 of FIG. 1 with jaws 14 and 16 being urged apart.

(47) FIGS. 25-27 illustrate perspective views of clamp 10 of FIG. 1 with jaws 14 and 16 being urged together by the resilience of resilient stainless steel strip 12 in U 22 of clamp 10.

(48) FIGS. 28, 29 and 30 are perspective views of upper and lower levers 28 and 40 of clamp 10 of FIG. 1 illustrating alignment protrusions 74 and alignment recesses 76 maintaining the proper interrelationship between levers 28 and 40 as well as slots 78 and 80 which resilient stainless steel strip 12 passes through in each.

(49) FIG. 31 illustrates gripping ridge 82 on upper surface 84 of upper lever 28 facilitating grasp upon upper lever 28.

(50) FIG. 32 illustrates gripping recess 86 on lower surface 88 of lower lever 40 facilitating grasp upon lower lever 40.

(51) FIGS. 33-38 illustrate all surfaces of upper lever 28 for completeness.

(52) FIGS. 39-43 illustrate all surfaces of lower lever 40 for completeness.

(53) FIGS. 44 and 45 illustrate clamp 90 which is an embodiment of the present invention formed from a strip of stainless steel 12 having interleaving upper tines 92 and lower tines 94 at each end thereof. In contrast to the embodiments shown in FIGS. 1-39, clamp 90 is opened by pressing inwardly on clamp 90 to urge tines 92 and 94 to interdigitate passing through each other rather than in essence prying them apart. Note that in this embodiment, plastic levers to separate the jaws may be conveniently omitted as only pressing force is required to open clamp 90. In FIGS. 44 and 45, it is preferred that each lower tine 94 have a width of less than about 4 mm, more preferably less than about 3.5 mm, still more preferably less than about 3 mm, even still more preferably less than about 2.5 mm, most preferably having a width of between about 1.5 mm and 2.5 mm so that as the lower jaw passes over the feed dogs, some portion of fabric 66 remains in contact therewith consistently.

(54) FIGS. 46 and 47 illustrate two different types of curvilinear portions 22 which may be employed in the practice of the present invention.

(55) FIGS. 48 and 49 illustrate an embodiment of the present invention in which window 54 is omitted from upper jaw 14.

(56) While the invention has been described in detail, modifications within the spirit and scope of the invention will be readily apparent to those of skill in the art. In view of the foregoing discussion, relevant knowledge in the art and references discussed above in connection with the Background and Detailed Description, the disclosures of which are all incorporated herein by reference, further description is deemed unnecessary. In addition, it should be understood that aspects of the invention and portions of various embodiments may be combined or interchanged either in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention.