US2016354A - Sewing machine - Google Patents

Description

ZJIMQEEAA V W. J. WORKMAN SEWING MACHINE Filed July 9, 1954 Patented Oct. 8, 1935 UNITED STATES PATENT OFFICE SEWING MACHINE Walter J. Workman, Lombard, Ill. Application July 9, 1934, Serial No. 734,312 9 Claims. (01. 112-235) This invention relates to sewing machines and more particularly to a pressure foot for such machines.

The pressure foot in a sewing machine urges the work into engagement with the feeding means which usually is in the form of serrated bars movable in substantially rectangular orbits and normally the pressure foot is mounted for pivotal movement in a vertical plane so that it will ride over any unevenness in the work being sewn. In sewing heavy materials such as work shirts and trousers, overalls and the like it is often necessary to sew transversely across a seam and when the pivotally mounted pressure foot rides up over such a seam the area of the pressure foot effective on the cloth to urge it into engagement with the work feeding means is often so reduced that sufiicient pressure is not exerted by the foot to properly engage the cloth with the feeding means and the work bunches up and improper sewing results.

The primary object of my invention is to provide a novel pressure foot for a sewing machine and which will effectively feed the work through 'the machine notwithstanding uneven thickness therein due to seams and the like.

Further objects are to provide a sectional pressure foot and to so mount the sections of the foot that when one section thereof rides over a seam or the like in the goods being sewn it will act on the other section thereof to effectively force this other section into engagement with the goods to thereby effectively engage the goods with the feeding means to insure constant feeding of the goods past the needle or needles in the machine; to independently mount the sections of the pressure foot so that the pressure exerted thereby may be independently adjusted to insure proper operation; to provide a pressure foot which may be incorporated in standard sewing machines, particularly those of the industrial'type, without extensive alterations therein; and to provide a pressure foot of simple and. economical construction and efficient and positive operation.

In th selected embodiment of my invention illustrated in the accompanying drawing Fig. 1 is a fragmentary side elevational view of the head of an industrial sewing machine and in which my novel pressure foot is included;

Fig. 2 is an elevational view looking in at the left hand end of the machine as shown in Fig. 1;

Fig. 3 is an enlarged detail view of the pressure foot looking in the same direction as Fig. 1 and showing the parts in their normal operative position;

Fig. 4 is a view similar to Fig. 3 showing the parts in position assumed when a seam or the like starts to move below the pressure foot;

Fig. 5 is a sectional detail view taken substantially on the line 55 on Fig. 3; and

Fig. 6 is a sectional detail view taken substantially on the line 66 on Fig. 3.

In the accompanying drawing I have illustrated the machine fragmentally since my pressure foot is not limited to use with any particu- 10 lar type or make of sewing machine. The machine includes a table I over which the work is fed and in which the usual feeding means is provided. This feeding means is in the form of bars generally indicated by 8 and which have serrated upper edges to effectively grip the cloth to be sewn, and the usual means are provided for moving the bars 8 in substantially rectangular paths, the bars being in upper position and moving toward the right as viewed in Fig. 1 during the operative phase of their movement in the rectangular paths. The cloth or work to be sewn, generally indicated by W, passes over the bars 8 and is urged into engagement therewith by the pressure foot of the sewing machine and it is to this part of the machine that my invention appertains.

The machine includes a head 9, at the forward end of which the needle bar I 0 is mounted for reciprocation and this bar in the present instance carries three needles H arranged in side by side relation and these needles are of the usual construction and the sewing operation is performed in the customary manner, this forming no particular part of my invention. The usual pressure foot bar [2 is mounted rearwardly of the needle bar it in bearings l3 and I4 mounted in vertical alignment with each other on one side of a depending part of the head 9. A cross rod I5 is connected to the pressure foot bar If! and to a vertically reciprocal bar 16 mounted in vertically aligned bearings l1 and I8 provided on the side of the depending part of the head 9 opposite the bearings i3 and M. The usual pressure foot spring l9 acts on' the bar it and urges the bars I6 and I2 toward the feeding means. A lever 2b is pivotally mounted on the head and is connected to bar It and it may be moved about the pivot therefor to move bars I6 and I2 away from the feeding means. The particular construction .of the just described parts may vary in different machines but a downwardly urged part, like the bar I2, is always provided.

An arm 2|, constituting a part of my pressure foot, is secured to the lower end of the bar I2 and includes a forwardly and downwardly extending part 2| at the lower end of which bearings 22 are provided. The front section 23 of the pressure foot includes bosses 24 in which recesses 25 are provided into which the bearings 22 are fit to thereby pivotally connect the section 23 to the forwardly and downwardly extending part 2 l for pivotal movement in a vertical plane. The action of the spring I9 is such that'the section 23 is forced downwardly toward the feed bars 8 to effectively clamp the work W in engagement with the feed bars. In the present machine wherein three needles H are provided three needle slots H are provided in the section 23 intermediate of and in alignment with the bosses 2d andthe needles l i operate through these needle slots I l. The needles are so located in the slots that the axis about which the section 23 pivots is aligned therewith.

An arrangement such as that thus far described operates satisfactorily on work of uniform thickness but'when a seam S or other abnormal thickness in the work is encountered it passes under the section 23, the seam being guided into such position by the upwardly extending guiding part 23 roundingly merged into the front end of the section 23. In Fig. 4 I have illustrated the section 23 as having been pivoted upwardly by a seam S passed into position therebelow. By referring to Fig. 3 it will be seen that when work of normal thickness is below the section 23 of the pressure foot the lower surface of the pressure foot presents substantial area which is sufficient to insure proper feeding of the work. However, when the section 23 is pivoted upwardly as illustrated in Fig. i it will be seen that the area of the section 23 engageable with the work is materially reduced and, as shown in Fig. 4, only the rear end of the front section 23 is engaging the work. This is usually not suflicient to insure feeding of the work which bunches up and prevents proper sewing.

To prevent bunching up of the work and insure proper sewing I provide a rear pressure foot section 2i which includes an upwardly extending lug 23 having a slot 29 therein into which the flattened end 23 of an auxiliary pressure foot bar 3! is extended and a screw or the like 32 passes through the slot 29 and the flattened end 363 to.

firmly connect the pressure foot section 21 to the auxiliary pressure foot bar 3 l. The auxiliary pressure foot bar 3! is mounted for vertical movement in the bearings l3 and I4 anda spring 32 acts on the upper end thereof to urge the bar 3! and the section 2i downwardly so that the section 2'1 will clamp work in engagement with the feed bars 3. An adjusting screw 33 mounted in a lug 34 on the head 3 acts on the spring 32 to tension the same and by changing the position of the screw 33 the tension of the spring 32 may be adjusted. A cross rod 33' is fast to the bar l2 and extends below a pin 33 on the bar 3! and when the bar I2 is moved away from the feeding means the bar 3i is also so moved by engagement of bar 34 with pin 33'.

In the normal operation of the machine. as illustrated in Fig. 3both the front section 23 and rear section 2? are effective in feeding work through the machine but when the front section is pivoted upwardly, as illustrated in Fig. l, and the area thereof in engagement with the work is reduced, the rear section 21 is relied upon for feeding the work, and my novel pressure foot is so constructed that when the front section 23 is pivoted upwardly the pressure exerted by the rear section 21 is increased and in this way proper feeding of the work is assured. In order to increase the pressure on the rear section 21 when the front section 23 is pivoted upwardly I provide rearwardly extending lugs 35 at the rear end of the front section 23 and in normal operation of the machine these lugs 35 extend above but do not engage the upper surface of the rear section 21, the lower edges of said lugs being inclined upwardly as indicated at 36 to provide sufficient relief to insure freedom of the lugs 33 from the upper surface of the rear section 22. When, however, the front section 23 is pivoted upwardly the lugs 35 engage the upper surface of the rear section 21 and in the upward pivoting of the section 23 the lugs 35 engage the upper surface of the section 2'! and provide a fulcrum about which the section 23 pivots and since the section 23 pivots about the lugs 35 as a fulcrum it is manifest that the pressure effective on the section 23 is transferred to the section 21 and this additional pressure coupled with the action of the spring 32 is sufficient to insure proper feeding of the work notwithstanding the positioning of a seam below the section 23.

Of'course, after the seam is squarely passed under the section 23 sufficient pressure will be exerted by this section to insure engagement of the work with the feed bars and feeding of the work. The forward end of the bottom of the section 2i is rounded to facilitate the passage of the work under the section 21. A forwardly extending toe 3'! on the section 21 engages a tapered rear edge 38 on the section 23' and limits pivoting of the section 23 when the section 21 is raised by the passage of a seam or the like below the section 21, this also raising section 23. The engagement of the toe 3! with the tapered edge 38 also has the effect of insuring effective pressure on the seam so as to hold it in engagement with the work feeding means and insure feeding thereof. 7 It is therefore manifest from the foregoing description that I have provided a sectional pressure foot for a sewing machine which will insure proper feeding of the work notwithstanding abnormal conditions such as the movement of a seam or the like into position below the pressure foot. Moreover, when additional feeding force is necessary one section of the pressure foot acts'on the other to apply the additional force and thereby no insures proper feeding of the work.

While I have illustrated and described a selected embodiment of my invention it is to be understood that this is capable of variation and modification and I therefore do not wish to be limited to the precise details set forth but desire to avail hyself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. A pressure foot for sewing machines having work feeding means and a pressure foot bar movable toward and away from the feeding means and yieldingly urged toward the feeding means, said foot including a front part for holding the work in engagement with the feeding means, means connecting said front part to said bar, a rear part for holding the work in engagement with the feeding means, support means independent of said bar and supporting said rear part, means acting on said support means and urging said rear part toward said feeding means, and means on said front part and engageable with said rear part upon pivotal movement of said front part away from said feeding means and adapted to urge said rear part forcibly to- 7 ward the feeding means upon said pivotal movement of said front part.

2. A pressure foot for sewing machines having Work feeding means and a pressure foot bar movsaid foot including a front part for holding the work in engagement with the feeding means, means connecting said front part to said bar, a rear part for holding the work in engagement with the feeding means, support means indeurging said rear part toward said feeding means, and lugs on said front part extending rearwardly therefrom over said rear part and nor- 3. A pressure foot for a needle, Work feeding foot bar movable toward and away from the feeding means and yieldingly urged toward the feeding means, said foot including a part for holding the work in engagement with the feeding means, said part having a needle slot therein through which the needle operates, an arm connecting said part to and providing recesses aligned with the needle and into which said bearings are fit to connect said part to saidarm for pivotal movement torear part toward said feeding means.

4. A pressure foot for a sewing machine having ing means, said which the needle operates, an arm connecting said part to said bar and having bearings at the free end thereof, means on said part and providing and normally spaced engageable with said rear part upon pivotal the front section on the rear section.

8. A pressure foot for urging work into engagement with the feeding means of a sewing machine rection relative 9. A pressure to the feeding foot for urging feeding means means,

WALTER J. WORKMAN.

from said rear part and

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