US2910024A - Sewing machine - Google Patents

Description

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Oct. 27, 1959 F. P. TAMBURRO SEWING MACHINE Filed April 19. 1955 3 Sheets-Sheet 1 II! J 0ct.,27, 1959 F. P. TAMBURRO' 2,910,024

SEWING MACHINE Filed April 19, 1955 n 3 SheebS-Shet 2 fly/0 40 .A /57 11% L INVENToR. ,fra/1cm P Tamar/-v Oct. 27, 1959 F, P, TAMBURRO 2,910,024

SEWING MACHINE Filed April 19, 1955 5 Sheets-Sheet 3 A] e :nr-

ln E w I' L i d il :i |,u @i Nl! QT' y o W I mf E o N w o K o E Si* N N N 0% INVENTOR. Fra/7cm" j? Tambwfo ATTORNEYS United States Patent O 2,910,024 SEWING MACHINE Francis I. Tamburro, Teaneck, NJ., assignor to Willcox & Gibbs Sewing Machine Co., New York, N.Y., a corporation of New York Application April 19, 1955, Serial No. 502,421 9 Claims. (Cl. i12-123)' The present invention relates to improvements in sewing machines and more particularly to improvements in atlock sewing machines. It is an object to improve sewing machines to increase the speed thereof and provide for better balance in operation. This is accomplished according to the present invention by providing an improved trimmer device, lubricating means and thread control device for the machine.

A feature of the present invention is the provision of trimmer means embodying a trimmer arm and drive therefor mounted independently of the presser foot bar whereby the weight of the trimmer is removed therefrom, permitting an increase in sewing speeds, and having on the arm a cutter blade cooperating to sever the edge of the fabric as it passes under the presser foot.

Also, a feature of the invention resides in driving from the trimmer arm the cross-thread hook and cross-thread carrier mounted on the presser foot and in providing a drive connection therefor permitting limited relative movement of the presser foot and elements carried thereby with respect to the trimmer arm during the sewing operation as it passes over varying thicknesses of materials.

Another feature of the invention resides in the novel cutter blade and holder therefor for properly presenting a cutting edge during the cutting operation.

A further feature of the invention resides in the provision of a spring carried by the presser foot bar and acting on the cutter blade carrier to maintain the cutter blade in cutting relation and to cushion such shock as might be present due to action of the feed shoes.

A still further feature of the invention resides in the improved lubrication for the needle bar shaft, needle bar levershaft and trimmer ann drive means whereby pressure andV gravity feed of the lubricant are employed to insure adequate lubrication at high speeds of the machine.

Another feature of the invention resides inthe novel thread guide carried by the work arm and controlling the high speed movements of the plurality of threads to the sewing mechanism at the higher rate of speed of the machine so as to prevent tangling and breaking of these juxtaposed threads.

Other features and advantages of the invention will be apparent from the specification and claims when considered in connection with the drawings in which:

Figure l shows a View partly in section of the sewing station with the trimmer arm and trimmer drive.

Fig. y2 is a sectional view taken along the lines 2--2 of Fig. 1. Y

' Fig. 3 is a view taken along lines 3--3 of Fig. 1.

Fig. 4 is aview partly in section taken along lines 4-4 of Fig. 2.

Fig. 5 is a sectional view taken along lines 5-5 of Fig. 2.

Fig. 6 is a detail sectional view taken along lines 6 6 of Fig. 4.

Fig. 7 is an enlarged top view of an end of the trimmer arm showing the cutter blade thereon.

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Fig. 8 is a longitudinal sectional view through the cutter means.

Fig. 9 is an end view of the cutter means.

Fig. 10 shows the blade-holding shoe.

Fig. 11 is a view taken along lines 11-11 of Fig. 10.

Fig. 12 is a sectional view taken through the bladeholding shoe.

Fig. 13 is a diagrammatic view showing the balanced relation of the presser bar spring andA cutter blade spring.

Fig. 14 shows a fragmentary side view of the thread guide which is located in the work arm.

Fig. l5 shows a sectional view through the arm showing the guide in extended and retracted position.

Fig. 16 is a top view of the machine partly in section showing the lubricating means for the needle bar lever shaft, and needle bar shaft.

Fig. 17 is a vertical sectional view through the needle bar shaft and housing showing the wick relationship for providing force-feed and gravity feed lubrication.

The present invention is an improvement on the flatlock sewing machine, of the type illustrated in the Borton Patent No. 1,041,574 to which reference may be made for the standard elements of a ilatlock machine. It has been found, however, that this machine is a relatively slow machine and in order to increase kthe speed the present invention provides a novel trimmer arm and drive therefor,v novelv lubrication at the sewing end of the machine and novel control means for the threads leading to the sewing station. l

The machine has a base 10 adapted to be mounted on a table (not shown), a work arm 11, and a frame 12 projecting above the basev and having the needle bar shaft 13 and needle bar lever shaft 14 mounted therein.

As shown in the drawings, the improved trimmer arm 15 is mounted independently of the presser foot bar so that the weight thereof is removed from the shaft thus permitting greatly increased operating speeds. In achieving this, the present invention provides a housing 16 adapted to be detachably Amounted on the end frame of the machine by suitable means-so as to overlie the ends of the needle bar shaft 13 and needle bar lever shaft 14. The end of the needle bar shaft is provided with an extension 17 secured thereto and having an eccentrically mounted ball connector 18 thereon. The ball connector 18 is connected by a connecting link 19 to an actuator arm 20 having its end secured to the trimmer arm shaft 21 mounted to oscillate in bearings 22, 23 formed in the lower housing section 16a, as shown in Figs. 1 and 2. The connector link is connected to the actuating shaft by means of a ball connection 24 so that as the needle bar shaft is rotated, it will oscillate the trimmer arm shaft in timed relation thereto. Thelower end of the trimmer arm shaft projects below the housing and has mounted thereon the trimmer arm 15, as shown in Figs. 1, 2 `and 5. The trimmer` arm is curved and 011.6 end is split andrprovided with a shaft-receiving portion 25 to receive the end of the shaft 21 which is cut away at 25a, 25b,. as shown in Fig. 5,v to cooperate with adjusting screws V26, 27 threaded therein so that its angular posi.- tion on the shaft can be accurately determined and set. After the arm is properly located it is Athen locked to the shaft. by bolts 28,Vthreaded in the ksplit section of the arm. By 'this arrangementV the arm canbe accurately adjusted on the shaft'to properly locate the trimmer mechanism. K,-

As shown in the drawings, the ,trimmer arm is provided at its opposite end with a cap 29 formounting a cutter blade carrier 30 forlslidingmovement toward and awayfrom a fixed blade 31 carried by a presser foot 3 2 at the end of the presser foot bar 33. The cutter 2,910,024 Patented oci. 27, 1959Y blade carrier has a slot 34 adjacent its upper end which interlocks with the flange 35 on a plunger 36 slidable on the arm so as to control movement of the cutter blade carrier. The lower end of the cutter blade carrier has clamped thereto a cutter blade shoe 37, shown in Figs. and 11, into which the cutter blade 38 isinserted and clamped by means of a clamping screw 39, as shown in Fig. 12. The cutter blade carrier has a. projecting bladeengaging shoe 40 provided with a rearwardly tapered undersurface 41 which is adapted to engage the cutter blade and cant it into a position in which the cutting edge 38a of the blade is moved into cutting engagement with the fixed blade.

As shown in Figs. 1 and 7, the cutter blade 38 is provided with a projecting tang 3817 which overlies the fixed blade in all positions of movement of the trimmer arm and maintains the blades in cutting cooperation.

In order to properly present the cutting edge of the cutter blade to the fixed blade in the event of longitudinal variations in the blade due to manufacturing tolerances, the cap 29 is pivotally mounted to move about the pivot 42. The lock screws 43 are located in enlarged openings 44 and permit this adjustment after Which they are tightened to hold the cutter blade in proper position to effect a cutting throughout the entire stroke of the cutter blade.

In order to maintain the cutter blade in cutting engagement, spring means are provided for applying a light pressure to the cutter blade. This means comprises a leaf spring 45 having one end 45a secured to the presser foot bar at the top of the presser foot. The spring is then provided with a tensioning U portion 45b and an enlarged opening 45e through which the presser foot bar passes and a free end 45d which is shaped as shown to engage the plunger 36 to cause the same to move the interlocked cutter blade carrier into engagement with the fixed blade. Preferably, the upper end of the plunger is provided with a ball 46 so as to provide point contact with the spring. It will be seen, therefore, that the cutter blade is normally urged with a light pressure into cutting relation. Further, the pressure of the spring 45 and the presser bar spring 47 (Fig. 13) are so balanced that the shock which may be occasioned by the usual action of the feed mechanism against the presser foot will be cushioned by the leaf spring.

The presser foot for the machine carries the usual cross-thread hook 48 secured to the lower end of shaft 49 pivotally mounted thereon. The upper end of the shaft has secured thereto aV link 50 which is connected by link 51 to a connector 52 connected to the trimmer arm so that as the trimmer arm is oscillated it will cause the cross-thread hook to oscillate during the sewing operation in the usual manner. Also driven from the linkage mechanism is a cross-thread hook 53 which is carried by a shaft 54 pivotally mounted in sleeve 32a on the presser foot, as shown in Fig. 6, and connected to the connector 52 so that the hook, too, is driven in timed relation to the sewing operation. Y v

A feature of the present invention resides in the arrangement wheren the connector -52 for actuating the cross-thread hook and cross-thread carrier is connected to the carrier arm to permit limited vertical movement of the presser foot with respect to the trimmer arm. This detail is best shown in Fig. 6 wherein it is shown that the trimmer arm is provided with a smooth, vertically disposed pin 55 freely passing through an aperture 56 in the connector so that the connector is free to slide vertically on the` pin to permit movement of the presser shoe over various thicknesses of material without interference by the trimmer arm which will continue the operation of the cross-thread hook and Vcross-thread carrier in timed relation with the sewing operation.

From the foregoing it will be seen that, by mounting the trimmer arm separately from the presser foot bar,

the speed of the machine can be greatly increased without affecting the operation of the presser foot during the sewing operation.

I have discovered that, in increasing the speed of the machine, the thread passing to the looper mechanism (not shown) cooperating with the four needles 57 (Fig. 3) had a tendency to whip and become entangled. To avoid this, the present invention provides in the Work arm 11 means for maintaining the threads in predetermined spaced relation. This is accomplished by providing a slot 58 in the `face 11a of the work arrn to extend from the upper edge to a finger-receiving recess 59 in the face, as shown in Fig. 14. Disposed in the slot is a thread guide bar 60 which, when in retracted position as shown in solid lines in Fig. l5, has its lower end projecting into the finger recess with the end curved at 60a to permit the finger to engage the bottom and move it to a projected position, as shown in dot and dash lines. In the projecting portion of the guide there are provided a plurality of thread guide eyes 61, one for each thread. It will be seen, therefore, that these guide eyes when in retracted position will hold the threads in spaced relation as they pass along the arm to the looper mechanism and prevent tangling. When raised in the upper position, the guide eyes are exposed and permit the arm to be rapidly threaded.

In order to retain the guide bar in its predetermined position on the arm, resilient means are provided to frictionally retain the guide bar. This means comprises, as shown in Figs. 13 and 14, a spring member or washer 62 disposed beneath the head of a screw 63. The member yieldingly presses against the guide bar to hold it in position. In accordance with the preferred form of the nyvention, the thread guide bar is provided with a depression 60b in its front face forming shoulders 60C, 60d at the ends thereof. The spring washer 62 is so located as to be disposed in the depression so that the shoulders engage the washer in either position of the thread guide bar to form stops therefor in either retracted or projected position and also prevent accidental disengagement of the thread guide bar. It will be noted that this construction is very simple and can be readily installed in the arm without dismantling the machine.

In order to run the machine at high speeds, it has been found desirable to improve the lubrication of the needle bar shaft, the needle bar lever shaft and, of course, the trimmer arm drive. This is accomplished in accordance with the present invention by improving the lubricating system as is illustrated in detail in Patent No.

' 2,299,439, to which reference is made, by providing a pair of oil-conducting lines 64, 65 extending from a driven pump 66 to the end of the frame. The lines each have one end connected to the pump by a fitting 67 which is provided with a screw-actuated valve 68 to control the rate of flow of the fluid under pressure to the end of the machine. 4The other end of line 64 terminates in the outer bearing 69 of the needle bar shaft 13 while the other end of the line 65 terminates in a passage 70 in the frame adjacent the inner bearing 71 for the needle bar lever shaft. The needle bar lever shaft 14 is hollow, as shown in Fig. l, and has its ends closed by means of wicking or packing 72, 72a. Oil from the line 65 and passage 70 passes into the shaft 14 and builds up pressure in the shaft. The oil then passes through the duct 73 to the crank bearing 74 of the needle bar lever 75 and passes from the crank bearing of the needle bar lever through passages 76 in the crank arm 77 to the eccentric portion 13a on the needle bar shaft. The frame is also provided with a passage 78extending from passage 70 to conduct oil from the line 65 to the inner bearing 79 for the needle bar shaft and excess oil drains off through passage 80 into the frame and is returned to the sump.

As shown in Figs. 16 and l7, oil from the hollow needle bar lever shaft passes through the wick 72 at the end of the shaft and into the wick 81 disposed in passages 82, 83 formed in the cover portion 16b of the housing and provides one terminal portion 81a which extends over the connecting link 19 to cause the oil to drop into a catch basin 19a formed in the link and through conduits 19b therein to lubricate the two ball connectors 18, 24. A wick 84 disposed in passage 85 also extends from the main wick 81 and causes lubricant to drop on the top of the lower housing section and be conducted through aV groove 86 to the top of the trimmer arm shaft so that it passes down along the shaft and lubricates the shaft. Any excess oil that drops into the bottom 16a of the housing is returned by the passage 87 into the frame and is returned to the sump.

It will be seen, therefore, that the oil is fed under pressure to the end of the frame and moves by gravity and pressure down through the passages to adequately lubricate the needle bar lever shaft, needle bar shaft and the trimmer arm shaft and the drive therefor.

Variations and modifications may be made within the scope of the claims and portions of the improvements may be used without others.

I claim:

1. In a liatlock sewing machine having a frame carrying a movable presser foot provided with a cross-thread hook and a cross-thread carrier in predetermined fixed relation thereon, a trimmer mechanism comprising a fixed blade on the presser foot, a trimmer shaft carried by the frame, a trimmer arm secured to the shaft, means oscillating the shaft in timed relation to the operation of the sewing machine, a cutter blade carried by the arm to be oscillated and cooperating with the fixed blade to trim the edges of the fabric feeding under the presser foot, and actuating means connecting the cross-thread hook and cross-thread carrier to the trimmer arm to be driven therefrom and including means providing for limited vertical movement of the presser foot, hook and carrier mounted thereon with respect to said trimmer arm without altering the predetermined fixed relation between said presser foot and hook and carrier.

2. In a atlock sewing machine having a frame carrying a movable presser foot provided with a cross-thread hook and a cross-thread carrier in predetermined fixed relation thereon, a trimmer mechanism comprising a fixed blade on the presser foot, a trimmer shaft carried by the frame, a trimmer arm secured to the shaft, means oscillating the shaft in timed relation to the operation of the sewing machine, a cutter blade carried by the arm to be oscillated and cooperating with the fixed blade to trim the 'edges of the fabric feeding under the presser foot, and

actuating means connecting the cross-thread hook and cross-thread carrier to the trimmer arm to be driven therefrom, said actuating means comprising a linkage mechanism having at one end means connecting said linkage to said arm for limited relative movement in the direction of movement of said presser foot whereby interference with movement of the presser foot is avoided and the hooks remain in the same predetermined relation with the foot without displacement or lateral movement with respect to said foot.

3. In a sewing machine including a frame carrying a driven needle bar shaft and a movable presser foot provided with a cross-thread hook and a cross-thread carrier in a predetermined fixed relation thereon, a trimmer mechanism comprising a fixed blade on the presser foot, a housing secured to the end of the frame and extending over the end of the needle bar shaft, a projecting trimmer shaft carried by the housing, a trimmer arm secured to the projecting portion of the trimmer shaft, means comprising eccentric means on the end of the needle bar shaft and link means connecting the trimmer shaft thereto to oscillate the trimmer shaft in timed relation to the operation of the sewing machine, a cutter blade carried by the arm to be oscillated and cooperating with the fixed blade to trim the edges of the fabric feeding under the presser foot, and actuating means connecting the cross-thread hook and cross-thread carrier to the trimmer arm to be driven therefrom and including a connection permitting limited vertical movement of said presser foot, hook and carrier with respect to said trimmer arm.

4. A trimmer mechanism for use in a sewing machine having a frame carrying a presser foot bar having a presser foot thereon comprising a fixed blade on the presser foot, a trimmer arm mounted on the frame independently of the presser foot bar and presser foot, means oscillating the trimmer -arm in timed relation to the operation of the sewing machine, said arm having a cutter blade carrier mounted thereon for sliding movement toward and away from the fixed blade and having a cutter blade thereon having a cutting edge cooperating with the fixed blade and adapted to trim the edges of the fabric feeding under the presser foot, and yieldable means comprising a U-shaped leaf spring carried by the presser foot bar and engaging and urging the blade carrier to move said cutter blade into cutting engagement with said fixed blade.

5. The invention as defined in claim 4 wherein said blade carrier has a projecting blade-engaging shoe to which said cutter blade is clamped, said shoe having a rearwardly tapering lower surface adapted to cant the cutter blade and maintain the cutting edge in cutting positio-n.

6. A trimmer mechanism for use in a sewing machine having a frame carrying a presser foot bar having a presser foot thereon comprising a fixed blade on the presser foot, a trimmer arm mounted on the yframe independently of the presser foot bar and presser foot, means oscillating the trimmer arm in timed relation to the operation of the sewing machine, said arm having carrier means for a cutter blade mounted thereon 4for sliding movement, the carrier means having the cutter blade secured thereto cooperating with the fixed blade and adapted to trim the edges of the fabric feeding under the presser foot, and yieldable means carried by the presser foot bar and having point contact with the carrier means to urge said cutter blade into cutting engagement with said fixed blade. y

7. A trimmer mechanism for use in a sewing machine having a frame carrying a presser foot bar having a presser foot thereon comprising a fixed blade on the presser foot, a trimmer arm mounted on the frame independently of the presser foot bar and presser foot, means oscillating the trimmer arm in timed relation to the operation of the sewing machine, said arm having a cutter blade carirer mounted thereon for sliding movement toward and away from the fixed blade and the carrier having a cutter blade thereon cooperating with the fixed blade and adapted to trim the edges of the fabric feeding -under the presser foot, a plunger slidably mounted on the trimmer arm and interlocked with the blade carrier to move the same, and spring means carried by the presser foot bar and engaging the plunger and urging the plunger and carrier toward the fixed blade and said cutter blade into cutting engagement with said xed blade.

8. A trimmer mechanism for use in a sewing machine having a frame carrying a presser foot bar having a presser foot thereon comprising a fixed bla-de on the presser foot, a trimmer arm mounted on the frame independently of the presser foot bar and presser foot, means oscillating the trimmer arm in timed relation to the operation of the sewing machine, said arm having a cap mounted at one end for pivotal adjustment about a transverse axis and having a cutter blade carrier mounted thereon for sliding movement toward and away 4from the fixed blade and the carrier having a cutter blade provided with a cutting edge thereon cooperating with the fixed blade and adapted to trim the edges of the fabric feeding under the presser foot, said cap being adjustable to enable the cutting edge to properly engage the fixed blade, a plunger slidably mounted on the trimmer arm and interlocked with the blade carrier in all adjusted positions of the cap, and spring means carried by the presser foot bar and engaging the plunger and urging the plunger and 7 carrier toward the Xed blade and said cutter blade into cutting engagement with said xed blade.

9. A trimmer mechanism for use in a sewing machine having a frame carrying a spring-pressed presser foot bar having a presser foot thereon comprising a fixed blade on the presser foot, a trimmer arm mounted on the frame independently of the presser foot bar and presser foot, means oscillating the trimmer arm in timed relation to the operation of the sewing machine, said arm having a cutter blade carrier mounted thereon for sliding movement toward and away from the fixed blade and the carrier having a cutter blade thereon cooperating with the fixed blade and adapted to trim the edges of the fabric feeding under the presser foot, a plunger slidably mounted on the trimmer arm and interlocked with the blade carrier tomove the same, a ball mounted on the top of the plunger, and a leaf spring carried by the presser foot bar and engaging the ball on the plunger with a point contact and urging the plunger and carrier toward the xed blade and said cutter blade into cutting engagement with said fixed blade.

References Cited in the le of this patent UNITED STATES PATENTS 498,617 Borton May 30, 1893 1,041,574 Borton Oct. 15, 1912 1,041,652 Merritt Oct. l5, 1912 1,274,666 Berger Aug. 6, 1918 1,384,829 De Voe July 19, 1921 1,403,807 Moffatt Jan. 17, 1922 1,410,057 Gatchell Mar. 21, 1922 1,733,867 Davidson Oct. 29, 1929 1,933,038 Zeier et al'. Oct. 31, 1933 2,157,371 Weis May 9, 1939 2,199,172 Gruman Apr. 30, 1940 2,327,768 Clayton Aug. 24, 1943 2,363,774 Christensen et al Nov. 28, 1944 2,407,587 Tamburro Sept. 10, 1946

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