US2807225A - Cording presser-foot for sewing machines - Google Patents

Description

sebt- 24, 1957 J. A. PlsANo I 2,807,225.

` CORDING PRESSER-FOOT FOR SEWING MACHINES Filed Aug. 18, 1955 INVENTOR; I

f//f ATMP/vf? 'JA/ff; A. P/sA/vof Amf United States Patent @thee 2,807,225 Y Patented Sept. 24, 1957 CORDING PRESSER-FOT FOR SEWING MACHINES .lames A. Pisano, Pittston Township, Luzerne County, Pa.

Application August 18, 1955, Serial No. 529,145

Claims. (Cl. 112-139) This invention relates to a cording presser-foot for sewing machines, and particularly to a presser-foot which 1 s capable of accommodating the sewing of cording of var1- ous sizes to articles of clothing, cushions, slip covers, and the like.

Although there are many types of cording presser-feet on the market today, these possess the distinct disadvantage of being limited in their application to a given size of cording. That is, currently available cording presserfeet are usually found to have a groove in the bottom surface thereof which receives and retains the cording as it is being sewn to a layer of fabric. Needless to say, a presser-foot of this type could not accommodate a variety of sizes of cording, since the groove ordinarily corresponds in size to the size of cording used, which means that a number of such devices having grooves of various proportions for different size cording must be kept on hand to be able to handle sewing operations requiring the application of cording of many sizes.

In addition, with the above type of presser-foot, two separate sewing operations are required in sewing cording between the edges of two layers of material. The cording is first sewn along the edge of one layer of material using the cording presser-foot, and then the work is transferred to another machine having a zipper foot, where the second layer of material is sewn to the cording. At this second machine, the operator must rely on his sense of touch to align the two layers. Obviously, production is slow and the rate of rejection of faulty pieces is high with this type of operation. Also, many of the presently available cording presser-feet are rigid unitary structures which do not yield to changes in the thickness of material being worked on, with the result that slippage of one layer of material relative to the other occurs as they pass beneath the presser-foot under the action of the sewing machine feed dog. Rejection of faulty pieces will again result.

With the above in mind, it is the foremost objective of the present invention to provide an improved cording presser-foot for sewing machines.

It is another object of this invention to provide a cording presser-foot for sewing machines which is capable of accommodating a variety of sizes of cording.

It is a further object of this invention to provide a cording presser-foot for sewing machines which is capable of applying cording between the edges of two layers of material in one sewing operation.

Another object of the present invention is to provide a cording presser-foot for sewing machines which is able to accommodate changes in thickness of material being worked on, so as to prevent slippage of one layer of material relative to another as they pass beneath the presserfoot under the action of the machine feed dog.

A still further object of this invention is to provide a cording presser-foot having an edge gui-de which maintains the cording in alignment, so that the needle will stitch the cording to the material layers in a continuous straight line.

These objects, together with other objectives and advantages to be derived from the present invention, will at once become apparent from a reference to the following detailed description of a preferred embodiment of the invention, and from the accompanying drawing, wherein similar numerals refer to similar parts throughout the several views.

Figure 1 is a side elevational View of the improved cording presser-foot shown attached to a sewing machine.

Figure 2 is a right side elevation of the improved cording presser-foot, partly in section, shown attached to a sewing machine presser-bar.

Figure 3 is a top plan View of the improved cording presser-foot.

Figure 4 is a bottom plan View of the improved cording presser-foot.

Figure 5 is a cross-sectional view of the present presserfoot, taken along the line 5 5 of Fig. 2.

Figure 6 is a front elevation of the improved cording presser-foot showing a section of cording in normal association therewith, and clearly illustrating the structure by which accommodation of various sizes of cording is made possible.

Referring to the drawings, and more specifically to Fig. 1 thereof, the improved cording presser-foot of the present invention is shown attached to a sewing machine having the usual arm mounted on a bed 10 and terminating in a head 11. The improved cording presser-foot indicated generally as 12, is fastened to a presser-bar 13 carried by the head 11, by means of a fastening screw 14. The presser-foot 12 keeps the material 15, to be sewn, engaged with the teeth of a feed-dog 16 operating through the opening in a conventional throat plate 17. The feed-dog is operated by a conventional sewing machine mechanism, not shown, which mechanism also drives the needle 18.

The presser-foot 12 comprises a shank 19 which is shaped to t the lower end of the presser-bar 13 in a conventional manner, as shown in Fig. 1. Two parallel ears 20 and 21 depend from the shank 19 to form supporting means for a pivot pin 22, as shown in Fig. 5. The inside faces of the ears 20 and 21 are smooth and parallel to form guide surfaces for the two presser-foot sole plates 23 and 24 which are pivoted on the pivot pin 22 in side by side relationship by means of their respective mounting lugs 25 and 26, as shown in Figs. 5 and 6. The right sole plate 24, as shown in Fig. 2, is provided with a U-shaped journal slot 27 so that said sole plate can move vertically with respect to the shank 19 and left sole plate 23 about the pivot pin 22. A pair of small coil compression springs 28 and 29 are seated ,in sockets provided therefor in the mounting lug 26 on opposite sides of the slot 27 so as to urge the sole plate 24 downwardly with respect to the shank 19, and to permit a vertical adjustment of said sole plate to accommodate Varying thicknesses of material 15 passing therebeneath.

The sole plate 23 is not adapted for vertical adjustment, as is the sole plate 24, but is capable of a slight pivotal movement about the pivot pin 22 under the restraint of the ear 20 bearing thereagainst, which ear is provided with a slight curvature as shown at v30 in Fig. 1. Vertical movement of the sole plate 23 is not necessary, since its novel structure, as will be described below, accommodates various sizes of cording without movement. As will be seen from Figs. 5 and 6, the work engaging surfaces of the sole plates 23 and 24. lie in different planes, the sole plate 24 normally lying vertically below the sole plate 23 under the biasing action of the coil springs 28 and 29.

The sole plate 23, which normally receives and aligns the cording for sewing, is substantially rectangular in its plan form configuration, as shown in the bottom plan view of Fig. 4, except for a portion cut out therefrom in its forward end 31. The remainder of the forward end 3i is disposed at an angle so as to provide a -bevel effect as shown clearly at 32 in Fig. 6. This angular disposition of the forward end 31 of sole plate 23 is material in permitting the accommodation of various sizes of cording, in a manner to be described b elow. The angle of inclination of said forward Vend 31 is upward in a direction toward the adjacent sole plate 24, and diminishes gradually in a rearward direction to a point where it merges with a longitudinally extending concave impression 33 in the rearward end of said sole plate 23, as shown in Figs. 4 and 5.

The sole plate 24 is also substantially rectangular in its plan form configuration, and 'has an aligning side extension 34 on its forward end, which extension lies in the cut out portion of the sole plate 23, in adjacent relationship with its angularly disposed forward end 31. In their side by side relationship, the sole plates 23 and 24, formed as described above, provide a recess 35 to accommodate the movement of needle 18 during the stitching operation.

Operation Although the operation of the present cording presserfoot should be quite apparent from the above description of its various parts and their relationship to one another, a brief description of its operation will be given below for the sake of clarity and completeness.

With the shank 19 attached to the presser-bar 13, in the manner described above, the recess 35 will lie directly below the needle 18. A length of cording 36 is inserted between the edges of two layers of material 15,V

So as to protrude therefrom as shown in Fig. 6; and the said cording and layers are fed beneath theV cording presser-foot so that the protruding cording 36 is receivedv beneath the angularly inclined forward end 31 of the sole plate 23, the layers of material passing beneath the sole plate 24. As the layers of material 15, with the marginal edge of the cording 36 therebetween, pass beneath the sole plate 24, said sole plate will adjust itself vertically to compensate for the thickness of material involved, under the joint action of the slot 27 about pivot pin 22 and the biasing coil springs 28and 2,9. At the same time, the cording 36 will be wedged against the side face of the extension 34 on the sole plate 24 by virtue of the pressure forces exerted thereon by the angularly inclined forward end 31 of thev sole plate 23, in the direction indicated by the arrow inFig. 6. Thus, regardless of the size of the cording 36, these pressure forces will cause the cording to seat itself in its proper position beneath kthe sole plate 23 against the aligning edge of the extension 34. This is obviously due to'the novel bevel effect of the forward end 31 ofthe sole plate 23 inclined in a direction toward the sole plate 24. Thus aligned, the needle 18, passing through the recess 35, will produce a continuous straight line stitch through the layers of material 15l and marginal edge of the cording 36. The importance of the extension 34 on the sole plate 24, in this respect, is selfevident. y

As the cording 36, thus attached to the layers of material 1,5', continues to move rearwardly under the action of the-feed-dog 16, it rides in the concave impression 33- in the rearward end of the sole plate 23. Thisconcave impression serves to maintain the sewn cording in alignment with the incoming cording for a short distance after it passes outwardly from beneath the rearward end of the presser-foot, thus precluding the incoming cording from being pulled out from under the angularly inclined forward end 31 ofthe sole plate, in a sidewise direction, so as to disrupt the sewingv operation.

YIthas -beenfoundthat 'the cording` presser-foot of the present invention, vasabove-de'scribed, can accommodate 21 with the same degree of efficiency cording sizes ranging from l; to 1/2 inch in thickness. And since the cording is attached to the material edges in one operation, the rate of production has been increased three-fold. In addition, the rate of rejection of faulty finished pieces has been materially reduced in view of the elimination of the two-stage stitching operation, as has been heretofore necessary. And due to the self-compensating adjustment feature of the sole plate 24, slippage of one layer of the material relative to another has been substantially eliminated. All of these advantageous features contribute to the production of a neatly finished low-cost product.

Although the present discussion of this invention has been limited to the above-described preferred embodiment, variations thereof are possible without departing from the spirit of the invention. It is to be understood, therefore, that the invention is not to be limited to the particular embodiment disclosed, but rather only to the inventive concept as defined by the appended claims.

What is claimed is:

l. A sewing machine cording presser-foot comprising, a shank adapted to interflt with a sewing machine presserbar, a yoke depending from said shank, a pivot pin extending transversely of said yoke, and a pair of relatively movable sole plates carried by said pivot pin in side by side relationship within said yoke, the forward end of one of said' sole plates remote from said pivot pin being inclined at an angle relative to a horizontal plane and in a direction toward the other sole plate, the aft end of said sole plate having a longitudinally extending concave impression inits bottom surface.

2. A sewing machine cording presser-foot comprising, a shank adapted to interfit with a sewing machine presserbar, a yoke depending from said shank, a pivot pin extending. transversely of, said yoke, and a pair of relatively movable sole plates carried by said pivot pin in side by side relationship within said yoke, the forward end of one of said sole plates remote from said pivot pin being inclined at an angle relative to a horizontal plane and in a direction toward the other sole plate, said inclined forward end merging with a longitudinally extending vconcave impression in the aft end of said sole plate in the bottom surface thereof.

3. A sewing machine cording presser-foot comprising, a shank` adapted to interttwith a sewing machine presserbar, a yoke depending from said shank, a pivot pin extending transversely .of said yoke, and a pair of relatively movable sole plates carried by said pivot pin in side by side relationship within said yoke, the forward end of one of said sole plates remote from said pivot pin being inclined'at an angle relative to a horizontal plane and in a direction toward the other sole plate, said forward end gradually diminishing in angular inclination in a rearward direction and merging with a longitudinally extending concave impression in the bottom surface of the aft end of said sole plate so as to provide a continuous longitudinal cord-receiving channel.

4. A sewing machine cording presser-foot comprising, a shank adapted to intert with a sewing machine presserbar, a' yoke dependingfrom said shank, .a pivot pin extending transversely of said yoke, land a pair of sole plates carried by said pivot pin in side by side relationship within said yoke, the forward end of one of said sole plates remote from said pivot pin having a recess cut in oneside thereof with the remainder of said end being inclined' at an' angle relative to a horizontal plane in a direction towardthe other' sole plate, said inclined forward end merging with a longitudinallyextending concave impression inthe bottom surface ofthe aft end of said sole plate, the other soleplate having a side extension on its forward end residing within the recess of said iirst'sole plate, said other sole plate being vertically movable relative to said first sole plate and said shank.

5. A sewing machine cording presser-foot comprising, a shank adapted to intert with a sewing machine presserbar, a yoke depending from said shank, a pivot pin extending transversely of said yoke, and a pair of sole plates carried by said pivot pin in side by sideerelationship within said yoke, the forward end of one of said sole plates remote from said pivot pin having a recess cut in one side thereof with the remainder of said end being inclined at an angle relative to a horizontal plane in a direction toward the other sole plate, said inclined end gradually diminishing in angular inclination in a rearward direction and merging with a longitudinally extending concave impression in the bottom surface of the aft end 0f said sole plate, the other sole plate having a side extension on its forward end residing within the recess of said rst sole plate, said other sole plate being springbiased so as to normally lie below the first sole plate and vertically movable relative to said first sole plate.

References Cited in the tile of this patent UNITED STATES PATENTS

Images