US2949085A - Presser foot for sewing machine - Google Patents

Description

Aug. 16, 1960 E. scHENKENGEL PRESSER FOOT FOR SEWING MACHINE Filed NOV. '7, 195'? United States f PRESSER FOOT FOR SEWING MACHINE Emerich Schenkengel, Kaiserslautern, Pfalz, Germany, assignor to G. M. Pfaff A.G., Kaiserslautern, Pfalz, Germany The invention relates to sewing machines and is more particularly concerned with a presser foot of the type having a sole and which is disengageably connected with the arm of the shank mounted on the presser bar which arm extends horizontally Iand in the direction of sewing.

In the presser feet of this type known heretofore the ushank member is normally not adapted to accommodate soles of different widths. However, in arrangements Where this is possible, the exchanging of the soles is extremely time consuming.

It is, therefore, an object of the invention to provide a presser foot having a sole construction which permits rapid exchanging of the sole, while at the same time insuring that the sole invariably assumes the correct position.

In accordance with the invention, this is accomplished in that the sole is slidable by means of coupling elements provided on its at upper surface, parallel to the working surface, onto retaining elements and can be locked on the arm in that position. It is another object of the invention to provide for simple and convenient manipulation during exchange of the sole which is attained primarily by arranging for the sliding operation for mounting the sole to be executed parallel to the working surface.

By virtue of the fact that the coupling elements are disposed in the lowest possible position the manufacture does not require very close tolerances, thus providing a considerable additional advantage. Further structural features of the invention and details about the advantages gained will become apparent from the following description of two embodiments of the new presser foot illustrated in the attached drawing in which vFig'. l is a perspective overall view of the presser foot mounted on the presser bar,

Fig. 2 is a perspective view showing the shank member and the sole of the presser foot in assembled condition,

Fig. 3 illustrates the details of the component parts with the sole of the presser foot removed from the shank,

Fig. 4 is a detail View of the locking member, and

Fig. 5 is a side elevational view of another embodiment of the shank member and of the sole connected pivotally thereto.

In the figures of the drawing like reference numerals refer to like or corresponding elements or details.

The presser foot comprises the shank member 1 and the sole 2. As shown in Fig. l the foot is secured to the presser bar of the machine in the conventional manner by means of a collar screw.

'Ihe shank member is provided with a horizontally disposed arm 3 extending in the direction of sewing having a slot-like recess in the direction of sewing. Supporting pins 5, 6 are mounted in the arm 3 at the same height and spaced from one another and extend through the recess 4. A latch 7 is received in the recess 4, resting against the rearward pin 6 proximate the arm junction for pivotal support to provide for vertical rocking movement and presenting a transverse bar S. The pivatent Patented Aug. `16, 1960 ICE otal movement of the latch is limited at the top by the wall of the recess'4 and at the bottom by he abutment or fit of a recess 7a of latch 7 adjacent the bar 8 over the pin 5. A leaf spring 9 is provided on the shank member 1 which rests against a pin 10 secured to that end of latch 7 which is opposite the bar 8. This suitably retains the latch 7 in the given position of pin 10 with reference to the retaining pin 6 which serves as axis of rotation in its limiting positions, i.e. in its locking position (Figs. 2 and 5) and in its upwardly shifted position (Fig. 3).

A pair of U-shaped strips 11,12 are provided at a distance from one another, corresponding to the width of Vthe arm 3 on the upper flat surface of the sole 2, which serve as coupling elements. These coupling elements coact with the pins 5, 6 of the shank member 1, theV ends of which project from the lateral sides of the arm and constitute retaining members. The open ends of strips 11, 12 facing the rearward portion of the sole receive the laterally extending portions of the pins 5, 6 when the sole is slide over pin 5 upon the horizontal vlower arm 3 of the shank member 1, parallel to the Working surface against the abutment formed by bridges 13, 1.4 of the closed ends of strips 11, 12. Thus the strips 11, 12 engage the sides of the arm 3 in secure alignment therewith. Thereupon the latch bar 8 can be shifted over or behind the bridge portions 13, 14 which rest against pin 5, which constitutes the locked position. lInasmuch as the latch 7 is retained in this locked position by the spring 9 the sole 2 cannot disengage itself automatically from the shank member 1.

The embodiment in accordance with Fig. 5 corresponds largely to the embodiment in laccordance with Figs. l-4. T he dierence in construction is in the shape of the upper leg portions of the strips 16 which are made as short as possible so that the strips merely encompass or reach around the support pin 5 which is proximate the free end of the arm. The sole 2 is then rockable about this pinS asindicated by the tilted position in Fig. 5 Where the sole 2 is inclined with respect to the horizontal arm.

In the embodiment in accordance with Fig. 5 unintentional displacement of the sole 2 out of the locked position on shank 1 is also impossible due to the latch bar 8 which is disposed over it. Consequently the arm 3 is shaped in a manner that any particular sole can be located thereon rigidly or tiltably, depending on whether 'the sole is provided with strips 11, 12 which reach with their free legs over the ends of the spacedly arranged pins 5, 6 which project from the sides of the arm (Figs. 1-3) or with strips 16 the free leg portions of which reach only around the pin 5 (Fig. 5).

The invention is not limited to the embodiments illustrated in the drawings as other forms of construction may suggest themselves which embody the inventive concept within the scope of the appended claims.

I claim:

l. Presser foot for sewing machine of the type adapted to be mounted on the presser bar of the machine and having a shank member and a horizontal arm extending substantially at right angles to said shank member, said foot comprising a sole having coupling elements disposed on the upper Surface thereof, each of said coupling elements presenting a slot and having a closed end, supporting elements on said arm adapted to slidably engage said slots on said coupling elements in a direction substantially parallel to the working surface of the machine and a rigid latch member pivotally supported on said arm presenting a transverse bar movable over said closed ends of said coupling elements for the locked position of said sole.

2. Presser foot for sewing machine of the type adapted to be mounted on the presser bar of the machine and' having a Shank member and a horizontal arm extending substantially at right angles to said shank member, said foot comprising a sole having coupling elements disposed on the upper surface thereof, supporting elements on said arm adapted to be slidably engaged by said coupling elements in a direction substantially parallel to the working surface of the machine and a rigid latch member pivotally supported on said arm presenting a transverse bar movable over said coupling elements for the locked position of said sole, said coupling elements comprising U-shaped strips adapted to engage the lateral surfaces of said arm with a sliding dit and having their open ends directed towards the rear portion of said sole and said supporting elements comprising supporting pins projecting at the same height and 4at a distance from one another through said arm.

3. Presser foot for sewing machine of the type adapted to be mounted on the presser bar of the machine and having a shank member and a horizontal arm extending substantially at right angles to said shank member, said foot comprising a sole having coupling elements disposed on the upper surface thereof, supporting elements on said arm adapted to be slidably engaged by said coupling elements in a direction substantially parallel to the working surface of the machine and a latch member pivotally mounted at one end on said arm and presenting a transverse bar at the other end movable over said coupling elements for the locked position of said sole, said vcoupling elements comprising U-shaped strips adapted to engage the lateral surfaces of said arm with a sliding fit and having their open ends directed towards the rear portion of said sole and said supporting elements comprising supporting pins projecting at the same height and at a distance from one another through said arm, said arm having a slotted aperture intermediate said lateral surfaces, said latch member comprising a member movable in said aperture and said transverse bar being movable over the arcuate portions of said U-shaped strips to press said strips against one said supporting pin.

4. Presser foot for sewing machine of the type adapted to be mounted on the presser bar of the machine and having a shank member and a horizontal arm extending substantially at right angles to said shank member, said foot comprising a sole having coupling elements disposed on the upper surface thereof, supporting elements on said arm adapted to be slidably engaged by said coupling elements in a direction substantially parallel to the working surface of the machine land a latch member pivotally mounted at one end on said arm and movable over said coupling elements for the locked position of said sole, said coupling elements comprising U-shaped strips adapted to engage the lateral surfaces of said arm with a sliding lit and having their open ends directed towards the rear portion of said sole and said supporting elements comprising supporting pins projecting at the same height and at a distance from one another through said arm said arm having a slotted aperture intermediate said lateral surfaces and said latch member comprising a member movable vertically in said aperture and having a transverse bar endwise thereof movable over the arcuate portions of said U-shaped strips to press said strips against one said supporting pin, said latch having pivotal support around one said supporting pin proximate the juncture of said arm with said shank and having a recess proximate said transverse bar adapted to engage said other pin and having a latch pin at the end opposite said bar, and a leaf spring being mounted on said shank for engagement with said latch pin to retain said latch in locked and in released position.

5. Presser foot for sewing machine of the type adapted to be mounted on the presser bar of the machine and having a shank member and a horizontal arm extending substantially at right angles to said shank member, and presenting a free support end, said foot comprising as a unitary component a sole having coupling elements disposed on the upper surface thereof, each of said coupling elements presenting a slot and having a closed end, supporting elements on said arm adapted to be slidably engaged by said coupling elements in a direction substantially parallel to the working surface of the machine and a rigid latch member pivotally supported on said arm presenting a transverse bar movable over said closed ends of said coupling elements for the locked position of said sole, said `coupling elements comprising U-shaped strips adapted to engage the lateral surfaces of said arm with a sliding t and having their open `ends directed towards the rear portion of said sole and said supporting elements comprising supporting pins projecting at the same height and at a distance from one another through said arm, said strips having upper leg portions of a length sufficient to encompass the pin ends adjacent said free support end of said arm thereby permitting tilting of said sole on said arm.

References Cited in the file` of this patent UNITED STATES PATENTS 1,488,309 Berg Mar. 25, 1924 2,549,269 Washburn Apr. 17, 1951 2,718,203 Armenti Sept. 20, 1955 2,770,206 Baehr et al. Nov. 13, 1956

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