US2448458A

US2448458A - Electromagnetic sewing machine

Info

Publication number: US2448458A
Application number: US512118A
Authority: US
Inventors: Joseph A Ozanich
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-11-29
Filing date: 1943-11-29
Publication date: 1948-08-31
Anticipated expiration: 1965-08-31

Description

8- 1948. J. AIOZANICH 2,448,458

ELECTROIAGNETIC SEWING MACHINE Filed Nov. 29, 1943 2 Sheets-Sheet 1 Aug. 31, 194$.

J. A. OZA NICH ELECTROIAGHETIC SEWING MACHINE 2 Sheets-Sheet 2 Filed Nov. 29, 1943 Patented Aug. 31, 1948 UNITED STATES PATENT OFFICE ELECTROMAGNETIC SEWING MACHINE Joseph A. Ozanich, Detroit,.Mlch.

Application November 29, 1943, Serial No. 512,118

9 Claims. 1

v This invention relates to sewing machines and has for an object to provide a simple, economical and speedy electric sewing machine.

Another object is to provide a sewing machine with integral motive power.

Still another object is to eliminate, from the moving mechanism within the machine, the usual gears and connecting rods which operate, with a considerable amount of external friction.

Yet another object is to leave the needle clear of the material when the machine stops operating.

Other objects and advantages will be apparent during the course of the following descriptions.

The aims and objects in view are attained by a pair of electromagnets which are adapted to alternately drive a combination of levers and are provided with switches whereby the current is switched from one magnet to the other at various intervals to provide variable sewing speeds. Resilient members are employed for connecting the said levers, a needle carrying shaft and a looptaker device, into a reciprocatory unit. Also driven by the said unit is a link pick-up, a work feeder, and a bobbin wind. The entire above said combination is housed in a base and a gooseneck which is hingedly mounted thereon and is adapted to be tilted upwards on its hinge so as to raise the needle and the pressure foot to allow free access thereto. The gooseneck in its lowered position allows the needle and the remainder of the said reciprocatory unit to operate with a minimum of motion in view of maximum efiicency in the said magnets and the said resilient members will respectively function with a minimum of flex. A spring held presser plate, mechanically connected with the said switches, is employed for manually controlling the operation of the said switches by pressure applied thereon and is adapted to cause the magnet driving the needle on its up stroke to be the last energized by bringing the contacts of the other said magnet out of their switching position when pressure on the said plate is released so as to leave the needle clear of the material and the flnalstitch will be completed when the machine stops operating.

The invention will be better understood by re-: ferring to the accompanying drawings of which Fig. 1 is a front elevation partly in section of a sewing machine embodying the invention. Fig. 2 shows in detail the speed control mechanism. Figure 3 shows the looptaking and work feeding mechanism. Fig. 4 shows the bobbin wind mechanism and Figure 5 is a diagram which shows the electric circuit.

The machine is constructed with a fiat bed or base I on one end of which is pivotally fitted a hollow standard 2 of an overhanging bracket arm 3 which terminates in a head 4.

The electromagnets 5A and 5-18 comprise each a core and its windings, are set within the hollow standard 2 and are electrically interconnected with a speed control device as shown in Figure 5.

Housed in the bracket arm 3 is a lever 8, which has a pivot 1. The said lever is preferably constructed of soft iron and extends within the magnetic field of the electromagnets 5-A and 5B and is driven thereby.

Set to reciprocate in head 4 is a needle carrying shaft 8 which is attached to the lever 8 by a resilient member 9 and carries a needle H by means of a clamp ID.

The presser foot I2 is of a slightly resilient nature to absorb vibration and is removably attached to head 4 and respectively fitted with needle II and feed cam 35.

Pivot l5, threaded lever l3 and member I4 interconnect said gooseneck to the base, thereby giving means of raising and lowering said gooseneck and the mechanism therein, and reducing movement of the needle I I and the relative mechanism and also giving means of raising and lower ing presser foot l2.

Link takeup I6 is driven by lever B and attached to the wall of the bracket arm.3 by means of a resilient member ll. The proper timing is determined by leverage and the resilience of the member l1.

Attached to the lever B is a U-shaped resilient member or pawl l8 which has one of its two prongs hooked as shown in Figure 4 so that rotary motion may be imparted to the cog wheel 59 during both the up stroke and down stroke of the lever B. The said cog wheel i9 has a shaft journaled through the wall of bracket arm 3 and protrudes sufilciently from the wall to hold a, bobbin.

The lever 20 is pivoted to the underside of the base i and is interconnected yieldingly with the lever B by means of the resilient members 2iA and 2i-B and the vertical member 22, and is a fairly large surface fitted in the base i nearv the needle so that the operator may simultaneously hold the material in position for sewing and bring pressure by hand on the presser plate 23. The surface of the plate is of a smooth finish so that material may lie between the hand and the plate and slide over the plate during the sewing operation even while pressure is maintained on the plate by the hand. The degree of pressure brought on the said plate will determine the speed at which stitches are formed, as will be later shown. The presser plate 23 rests on a coil spring 24 which gives resistance to the pressure brought on the said plate and returns the plate to its normal position when the pressure is released. The bracket 25 houses the remainder BAASAES of the speed control mechanism and is attached to the underside of the base l. Member 2b extends from the presser plate 23 and is attached to the non-conductive member 2i which is pivoted at 2% and carries contact strips iii-4i and lit-B, Sit-4i and lid-l3 respectively. The contact strips 29-h! and 2Q-B are electrically wired to the electromagnet 6--A. and contact strips 33-A and lliB are electrically wired to the electromagnet ii-B. The contactor 30 is carried by and insulated against the wheel 32. The non-conductive member 36, in its normal position rests against the lever 28 and holds in position the contactor til so that when the presser plate 23 is pressed, member 2?! will swing on its pivot iii and the free ends oi the contact strips 29-A and flit-B will swing over and contact the contactor 3t, thereby closing the circuit through the eiectromagnet -A which will drive the lever 28' on its downward stroke. The motion of the lever to will cause the wheel 82 to swing by means of the memher @i and the contactor 36 will contact the contact strips tit-A and 33-B, thus closing the circuit through the electromagnet Ei-B which will drive the lever 20 back to its original position The tension spring 86 which is attached to the wheel 32 and member 21, will bring the contactor Bil back to contact the strips 29-A and 29--B for a repeat movement. The greater the pressure on the said plate 23 the further member 27 will swing on its pivot 28, thus shortening the contacting distance between the said contact strips and will simultaneously increase the tension on spring i i to cause a faster return of the contactor til. When the presser plate 23 is released, the contact strips 29-A and 29-3 will rise slightly above the contactor 36. The tension of the resilient member 36 holds the non-conductive member ii against the lever in its normal position. The a means of the contactor 30 and also to allow the contact strips 29-A and 29-B to rise clear of the said contactor 30!. Thus, whenever the presser plate 28 is released the last contact will be with the contact strips 33A and 33-3, thereby leaving the needle in a raised position, clear of the material and the final stitch will be completed.

The looptaking mechanism, Figure 3, is preferably constructed of light weight material and is set to operate complementary with the needle i i. It is comprised of a hook it, a bobbin case M, and a bobbin case restrainer 35. Said bobbin case restrainer may be restrained against rotation with the hook 33 in the usual manner. The said looptaking mechanism is carried by a cylindrical member 36 and has a shaft t2 which is Journaled to the underside of the base i. The resilient member 31 is attached to the lever 26 and the cylindrical member 38. Thus in operation when the lever '20 takes a downward stroke, it pulls on the resilient member 31 causing the hook 43 to rotate in one direction. Simultaneously the needle takes a downward stroke. When the lever 20 takes an upward stroke the tension on the resilient member 31 will be released causing the looptaker 43 to return in the opposite direction catching the loop formed by the needle I I as it rises on its upstroke. The hook i3 is predetermined to turn over sufficiently so as to bring the loop around the bobbin case so the link takeup may pull up the slack freely. The motion of the hook 43 is greater in ratio to the motion of the needle ii. Thus the book 68 may be properly timed to receive the loop formed by the needle ii.

The feed cam 8b is fitted in a guide plate lll which is attached to the base i. The said cam W- carries a slotted member 355. The cam 38 is attached to the periphery of the cylindrical mem ber 88. The leaf spring do is attached edgewise to the periphery of the member 38. In operation the feed cam must be timed to complete its forward stroke before the needle ii pierces the material. When the lever 29 begins its down stroke the cam 33 journals through the slot of member tit forcing the feed cam 35 to rise and advance. As cam clears the slot of member as, the feed cam 35 is caused to fall and return by the coil springs dilA and MB. As the lever 2@ takes an upward stroke the cam 83 and the leaf spring d6 journal along each side of the member 39 in their return motion. The leaf spring Sb holds the member 89 in position for a repeat engagement with the cam 538.

In view of maximum efiiciency in the electro magnets @A and 5B, the needle ii is predeter mined to operate with the shortest stroke necessary for the proper formation of stitches and advancing of the work. The combination of the pivotal gooseneck provides a means to raise the needle ii and the presser foot 02 up out of their normal sewing position to allow convenient access to the work, the needle, and the presser foot. The levers t and 20 will respectively reciprocate with a minimum of motion and will cause a minimum of flex on the various resilient members. The said resilient members are predetermined to hold the levers t and 2t and the relative elements in a yieldingly normal position and when they are in their extreme flexed position they will possess greater resistance or potential energy, thus overcoming a certain degree of inertia found in the reciprocatory elements of the machine.

Indicated in Figure 1 is an auxiliary switch ll for holding the circuits of the magnets EA and 53 open while the gooseneck is in its raised position to protect the machine against accidental operation while material is adjusted under the needle.

The operation of the hook it will be more clearly understood by noting that the downward force of the lever 28, pulling on the resilient member or coil spring 37, carries the hook it in one direction. At the upward stroke of the lever 2d the tension on the spring 37 is released allowing the spring to recoil. It is this recoiling action of the spring 37 which carries the hook 43 in the opposite direction.

In the foregoing description numerous constructional details and refinements have not been set out. it being the main object to disclose the invention. It also is to be understood that the form of this invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention which is defined by the following claims.

I claim:

1. A sewing machine having a base and a gooseneck, a needle driving lever fitted in the said gooseneck, a looptaker driving lever fitted below the said base and yieldingly connected with the other said lever, a pair of electromagnets for alternately driving the said levers in each of their two directions, and means for raising the gooseneck up out of its normal sewing position to allow free access to the work and the needle.

2. In a sewing machine having a base,'a gooseneck pivotally mounted thereon, a presser foot attached to the head of the said gooseneck, means to tilt the said gooseneck on its pivot to allow the presser foot to be raised up out of its normal position, a pair of electromagnets disposed in the standard of the said gooseneck, a pair of levers interconnected by a spring and pivoted in the said base and gooseneck to be driven by the said magnets, a needle carrying shaft driven by one of said levers, a looptaker device driven by the other of said levers and timing switches operable by one of said levers for alternately closing the circuits through each of the said magnets.

3. In a sewing machine having a needle carrying shaft, a looptaking device carried by a shaft and adapted to rotate in a forward and backward motion. a pair of pivoted levers, resilient means interconnecting the said levers and each of the said levers with the needle carrying shaft and the looptaking device respectively. a pair of electromagnetic devices each of the said devices being adapted to drive the said levers in each of their two directions and switches adapted to alternately close the circuits through each of the said electromagnetic devices.

4. In a sewing machine having a reciprocatory needle carrying shaft. a complemental looptaker device carried by a shaft and adapted to rotate in a forward and backward motion. a pair of pivoted levers, resilient members interconnecting the said levers and each of the said levers with the needle carrying shaft and the looptaker device respectively, a pair of electromagnetic devices each device adapted to drive the said levers in one of their two directions, switches for alternately closing the circuits through each of the said devices comprised of electrical contacts for the windings of each of the said devices and a swinging contactor driven in one of its directions by one of said levers and returned by a resilient member and a manually operable spring pressed presser plate adapted to control the contacting distance between the said contacts and the tension on the said resilient member to define speeds.

5. In a sewing machine having a needle carrying shaft, 9. looptaker device carried by a shaft and adapted to rotate in a forward and backward motion, a pair of pivoted levers, resilient members interconnecting the said levers and each of the said levers with the needle carrying shaft and the looptaking device respectively, a pair of electromagnetic devices each device adapted to drive the said levers in one of their two directions, switches adapted to alternately close the circuits through each of the said electromagnetic devices and a bobbin rotating means comprised of a cog wheel having a bobbin carrying shaft and a pawl reciprocated by one of the said levers and engaging the said cog wheel to transmit rotary motion thereto.

6. In a sewing machine having a base, a gooseneck pivotally mounted thereon. a needle carrying shaft adapted to reciprocate in the head of the said gooseneck, a complemental looptaker device adapted to operate in a forward and backward motion in the said base, upper and lower levers pivoted in the said base and gooseneck, resilient members interconnecting the said needle carrying shaft with one of the said levers, the

looptaker device with the other of said levers and the said levers with each other so as to form a reciprocatory unit, a pair of electromagnets arranged to alternately drive the said unit in each of its two directions, means to switch the current from one magnet to the other at various intervals to define speeds and means holding the said pivotal gooseneck in a normal sewing position and in a tilted position to allow free access to the work and the needle.

7. A sewing machine having a base, a gooseneck hingedly mounted thereon, a presser foot attached to the head of the said gooseneck, a needle carrying shaft adapted to reciprocate in the head of the said gooseneck, a complemental looptaker device journaled in the said base and adapted to rotate in a forward and backward motion. a feed cam driven thereby. a pair of pivoted levers disposed within the said base and gooseneck respectively, resilient members interconnecting the said levers and each of the said levers with the needle carrying shaft and the looptaker device respectively, a pair of electromagnets adapted to alternately drive the said levers in each of their two directions, switches for alternately switching the current from one magnet to the other at various intervals to define speeds, a manually operable presser plate fitted in the said base and mechanically adapted to control the operation of the said switches, a link pick up driven by one of said levers, a bobbin wind comprised of a cog wheel adapted to be rotated by a pawl which is reciprocated by one of the said levers, a screw lever adapted to tilt the said gooseneck up out of its normal position to allow free access to the work, the needle and the presser foot and an auxiliary switch for opening the circuits when the gooseneck is in its raised position to protect the machine against accidental operation while material is being adjusted below the said needle.

8. In a sewing device, the combination of a reciprocatory needle carrying shaft, a complemental looptaker device carried by a shaft and adapted to operate in a forward and backward motion, a pair of pivoted levers, and resilient members interconnecting the said levers and each of the said levers with the needle carrying shaft and the looptaker device respectively.

9. In a sewing machine having a reciprocating needle carrying shaft, a complemental looptaker device adapted to operate in a forward and backward motion, a combination of reciprocating levers, resilient members interconnecting the said levers and each of the said levers with the needle carrying shaft and the looptaker device respectively and a pair of electromagnets for alternately driving the said levers in each of their two directions.

JOSEPH A. OZANICH.

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

UNITED STATES PATENTS Number Name Date 361,426 Looker Apr. 19, 1887 579,511 Biggar Mar. 23, 1897 1,196,160 Schoolfield et al. Aug. 29, 1916 2,223,330 Naul Nov. 26, 1940 FOREIGN PATENTS Number Country Date 284,500 Germany May 28, 1915 548,239 Great Britain Oct. 1, 1942