US2578225A - Feeding device for sewing machines - Google Patents

Description

Dec. 11, 1951 R. CASAS-ROBERT ETAL 2,578,225

FEEDING DEVICE FOR SEWING MACHINES Filed March 51, 1949 4 Sheets-Shet 1 hum/mes Dec. 11, 1951 R. CASAS'ROBERT ET AL 2,578,225

FEEDING DEVICE FOR SEWING MACHINES 4 Sheets-Sheet 2 Filed March 31, 1949 y [mew/Ms 166% (kr/Zr-5a zrAZw/v/Zwer Mi Dec. 11, 1951 Filed Fig.3

R. cAsAs-RoBERT ET AL 2,578,225

FEEDING DEVICE FOR SEWING MACHINES 4 Sheets-Sheet 5 Dec. 11, 1951 R. CASAS-ROBERT ET AL 2,

FEEDING DEVICE FOR SEWING MACHINES Filed March 51, 1949 4 Sheets-Sheet 4 IIIIIIIIIIIIIIIIII II III"! I] In 26 llm rkmim w m I Patented Dec. 11, 1951 FEEDING DEVICE FOR SEWING MACHINES Ramon ,Casas Robert and Jean Court, Geneva,

s w itzerland, assignors to MefinaS. A., Binningen, Swi tzerland, a corporation of Switzer- Application March 31, 1949, :Serial No. 8,4,6,10 In Switzerland December 20, 1948 Claims. (Cl. 112- 210) The present invention relates to anactuating mechanism for the feeder of a sewing machine which differs from the known mechanisms yffihe fact that the said feeder is carried by asupport connected to an actuating element by mean of two levers, the first one of which is rigid and rocks around a fixed vertical axle, while 13116560, and one is elastic, in order to enable it vto follow the displacement of the first one and rocl s around a fixed horizontal axle.

The attached drawing shows diagrammatically and by way of example a form of execution of the mechanism.

Fig. 1 is a perspective View Fig. 2 is a side View;

Fig. 3 is a top view of the mechanisms housed in the lower ,arm of the sewing machine;

Fig. 4 is a vertical section view .of the column of the machine.

As shown in the attached drawing, the actuating mechanism for the feeder vor feeding device I includes a cam 2 rigidlyfixed to a shaft 3 driven in rotation by a driving shaft P of the sewing machine through a belt B. This cam 2 is connected to the feeder by two transmission levers, of which one imparts to it a rocking movement in a horizontal plane and the other, a rocking movement in a vertical plane.

The first transmission device includes aboss .14 carried at one end of a first arm 5 and inwhich is fixed an axle v6 of which the ends slide into bores or guides giprovidedin the two branches of a support I having the general form of a U. The feeder I is rigidly fixed on the upper face 8 of the support I. The arm 5 has, at its end opposite to that carrying the bossA, two branches 9 (Fig. 2) arranged in the formofa fork and between which is engaged one ofthe ends of a second arm I Ii. These two arms 5 and II] are rigidly connected one to the other by an adjusting and locking element II to form a lever rockably mounted on a common fulcrum-axle I2, of which the ends are rigidly fixed in the branches of a support I3 rigidly fastened to the frame IA of the machine by means of fasteningelements 1). The arm I8 carries two guides I5 and I-B (Fig. 3) into which slides a rod I'I carrying adriving carriage I8. The latter has:

(1) A guiding finger I9 sliding into a guide 20 carried by the guide I6 of arm I0;

(2) A cam following surface 2| kept in contact with the profile of the cam 2 by a spring 22 mounted on the rod I1 and resting, on the one hand, on face 23 of guide l6, fastenedto the arm I0 and, on the other hand, on a stop 24 fixed to the rod I'I;

(3) A part 25 slidably engaged in a slot provided ina guide 26 fastened on the end of a control shaft s, of which the angular position can be chosen and fixed at will by means of a controlling member 0 having a cam surface 2) engaged by the end of a lever fixed on shafts and urged against cam 12 by a spring 1'.

The second transmission device includes a lever consisting of an elastic blade 2'1 in one end of which is cut out a tongue 36 of triangular form. The blade 21 and tongue 36 are secured to a part 28 by means of a bridge 31 and rivets 42. The part 28 has the shape of a U, of which the two wings-are connected together by one of the arms of an L-shaped part 29. The second arm of this part 29 serves as an actuating finger 3i? kept in contact with the profile of the cam 2 by a coil spring 3|. The tongue 3% carries an axle 32 freely pivoted in a bearing 48 carried in the support I3. This axle 32 is horizontal and is kept in position in the bearing 40 by a stop element 4|.

The finger 30 is engaged in a guide provided by a slot 38 in the free end of a rod 39, rigidly fastened to the frame of the machine, and on which is mounted the return spring 35. he end of the elastic blade 2'! has a notch ed in which is engaged the end of an axle 3d freely mounted in the bore of a boss 35 provided in the support I.

The operation of the described mechanism is as follows:

' When the cam 2 is driven in rotation, it actuates simultaneously the finger 3i? and the follower 2| against the actions of the return springs 22 and. 3I. The guide 26 being positioned with its slot inclined in relation to a plane perpendicular to the driving shaft 3 and the part 25 being compelled to follow the slot in the guide 26, the reciprocation of the cam follower 2 I. causes the rocking of the lever 5, I0 about the vertical axle I2. Thus, the guide 1 is actuated in a to and fro movement in a horizontal plane and carries the support I along with it by means of the axle 6 engaged in the guides g. The end of the blade 2! is oscillated by the movements of supports 1 against its elastic action which tends to keep said blade in the plane of the tongue 33 which is held on axle 32 and in the slot 33. The actuating of the finger 30 by cam 2 causes the rocking in a vertical plane of the lever, composed of the parts 21, 28, 29 and 36, around the axis of the horizontal axle 32. This rocking movement is effected against the action of the return spring 3|.

Thus, the axle 43 is driven in a rocking movement in a vertical plane and due to the resilient nature of arm 21, it can follow the horizontal rocking movement imparted to the axle 6 by lever 5, 18.

From the above explanations and by examining the attached drawing, it can be seen that the support 1 is connected to the cam 2 by means of two levers, of which the first one 5, ill is rigid and rocks around a fixed axle l2, while the second one (21, 28, 29, 3G and 36) is elastic and rocks about the horizontal axis 32 of the bearing it. The two rocking movements imparted to the support '1 being effected by a single cam 2, their synchronism is automatically ensured. Finally, by modifying the inclination of the slot in the guide 263 in relation to a plane perpendicular to the shaft 3 by rocking the controlling element 0, it is possible to modify, to reverse or even to eliminate the extent of the horizontal to and fro movement of the axle 6 and therefore to fix at will the direction and the pitch of the advancement of the cloth by the feeder I.

In addition, as shown on the drawing, the points of contact on the cam 2 of the finger 30 and of the cam follower 2| are spaced angularly by about 90", so that the two rocking movements are dephased by 90. Lastly, the surfaces 1' of this cam are connected together by surfaces m having the form of arcs of circles centered on the rotation axis of the cam, the result is that the arms are alternately driven, so that the feeder is displaced by the actuating mechanism along an approximately rectangular path, and that it is always displaced horizontally and at a constant height over practically all the length of its advancement stroke, irrespective of the extent of said stroke over the upper or lower level of the work plate w. This feature is also of great importance, because it ensures an absolutely regular feeding of the cloth and avoids any stretching of the latter.

The bore made in the arm 9 for the screw H has a dimension sufiicient to permit the adjustelement, a rigid lever mounted for rocking movement about a fixed vertical axis, means associated with the driving element for transmitting horizontal oscillating movement to one end of said lever, means transmitting horizontal oscillating movement from the other end of the lever to said feeding device, a second lever mounted for rocking movement about a fixed horizontal axis, said second lever having an input arm and an output arm, means for transmitting oscillating movement in a vertical plane to the end of the input arm, and means for transmitting vertical oscillating movement from the end of the output arm to said feeding device, said output arm being rigid in a vertical plane to effect the transmission of vertical oscillation, and flexible in a horizontal direction to enable the feeding device to oscillate in a horizontal plane without affecting the input arm of the second lever.

3. An actuating mechanism for the feeding device of a sewing machine comprising a driving element, a cam carried by said driving element, a rigid lever mounted for rocking movement about a fixed vertical axis, means including a cam follower engaging said cam for imparting horizontal movement to one end of said lever about said verticalaxis, means transmitting horizontal oscillating movement from the other end of the lever to said feeding device, a second lever mounted for rocking movement about a fixed horizontal axis, said second lever having an input arm and an output arm, means connecting the output arm of the second lever to the input arm thereof to render the output arm rigid with the input arm in a vertical plane but to enable the output arm to oscillate in a horizontal plane relative to the input arm, means engaging said cam for imparting oscillating movement to the end of the input arm, and means for transmitting ing at the factory of the horizontal position of the feeder I in relation to the needle N for a given position of the cam 2.

A form of construction of the actuating mechanism for the feeder of a sewing machine has been described here by way of example and with reference to the attached drawing, but it is obvious that all the described parts can be simply replaced by their equivalents.

We claim:

1. An actuating mechanism for the feeding device of a sewing machine comprising a driving element, a rigid lever mounted for rocking movement about a fixed vertical axis, means associated with the driving element for transmitting horizontal oscillating movement to one end of said lever, means transmitting horizontal oscillating movement from the other end of the lever said feeding device, a second lever mounted for rocking movement about a fixed horizontal axis, said second lever having an imput arm and output arm, means connecting the output arm of the second lever to the input arm thereof to render the output arm rigid with the input arm in a vertical plane but to enable the output arm to oscillate in a horizontal plane relative to the input arm, means for transmitting oscillating movement in a vertical plane to the end or" the input arm, and means for transmitting vertical osciliating movement from the end of the output arm to said feeding device.

2. An actuating mechanism for the feeding de-- vice of a sewing machine comprising a driving vertical oscillating movement from the end of the output arm to said feeding device.

4. An actuating mechanism for the feeding device of a sewing machine comprising a driving element, a cam carried by said driving element, a rigid lever mounted for rocking movement about a fixed vertical axis, means including a cam follower engaging said cam for imparting horizontal movement to one end of said lever about said vertical axis, means transmitting horizontal oscillat'mg movement from the other end of the lever to said feeding device, a second lever mounted for rocking movement about a fixed horizontal axis, said second lever having an input arm and an output arm, means connecting the output arm of the second lever to the input arm thereof to render the output arm rigid with the input arm in a vertical plane but to enable the output arm to oscillate in a horizontal plane relative to the input arm, means engaging said cam for imparting oscillating movement to the end of the input arm, and means for transmitting vertical oscillating movement from the end of the output arm to said feeding device, said cam having two opposed partially cylindrical surface portions of different radii, and concentric with the rotation axis of the cam, connected by inclined ram portions and said cam follower and the means for imparting oscillations to the end of the second lever engaging the surface of said cam at regions circumferentially spaced apart, about 5. An actuating mechanism for the feeding device of a sewing machine comprising a driving element, a cam carried by said driving element, a rigid lever mounted for rocking movement about a fixed vertical axis, a driving carriage mounted on one end of said rigid lever for sliding movement longitudinally of the lever, a cam follower fixed on said carriage and engaging said cam so that rotation of the cam imparts reciprocating movement longitudinally of said lever, a guide element mounted for rotation about an axis parallel to the axis of said lever and provided with a diametrically extending guide slot, means carried by said carriage and extending into the slot of the guide element and operable to impart horizontal oscillating movement of the carirage and the end of the lever carrying the same about said vertical axis, means transmitting horizontal oscillating movement from the other end of the lever to said feeding device, a second lever mounted for rocking movement about a fixed horizontal axis, said second lever having an input arm and an output arm, means connecting the output arm of the second lever to the input arm thereof to render the output arm rigid with the input arm in a vertical plane but to enable the output arm to oscillate in a horizontal plane relative to the input arm, means engaging said cam for. imparting oscillating movement to the end of the input arm, and means for transmitting vertical oscillating movement from the end of the output arm to said feeding device.

RAMON CASAS ROBERT.

JEAN COURT.

REFERENCES CITED The following referenees are of record in the file of this patent:

UNITED STATES PATENTS Number

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