US2102954A

US2102954A - Rotary loop taker

Info

Publication number: US2102954A
Application number: US128572A
Authority: US
Inventors: Richard K Hohmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-03-02
Filing date: 1937-03-02
Publication date: 1937-12-21
Anticipated expiration: 1954-12-21

Description

Dec. 21, 1937, R. K, HOHMANN 2,102,954

ROTARY LOOP TAKER Filed March 2, 1957 ATTO R N EY Patented Dec. Z1, 1937 .Y UNITED STATES PATENT OFFICE 7 Claims.

The general object of the present invention is to provide an improved rotary loop taker for use in sewing machines of the rotary hook type.

A more specific object of the invention is to provide improvements simplifying and cheapening the construction of a loop taker adapted to receive a bobbin carrier of standard construction. Another specic object of the invention is toprovide a rotary loop taker of the type comprising 1G a hook ring formed separately from, and detachably connected to a spider or hub portion of the hook member, and which is specially shaped to adapt the loop taker for the use therewith of a bobbin carrier of larger diameter relative to the hook ring diameter than has heretofore been possible. Another specific object of the invention is to provide a rotary loop taker with a detachable part of novel form and comprising a loop deflecting edge and a loop discharging spur.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, and specific advantages attained with its use, reference should `be had to the accompanying drawing and descriptive matter in which I have illustrated and described a preferred embodiment of the invention.

Of the drawing:

Fig. lv is an elevation, partly broken away and in section, of a rotary loop taker;

Fig. 1A is a plan of a portion of the loop taker shown in Fig. l;

Fig. 2 is a section onv the broken line 2 2 of Fig. 1

Fig. 3 is a section on the line 3-3 of Fig. l; Fig. 4 is a perspective view, with parts broken away and in section, illustrating the manner o in which the bobbin carrier is moved into and out of operative relation with the hook ring;

Fig. 5 is a perspective view of the hook ring and a loop deflecting and discharging spur part detachably connected to the hook ring;

.l5 Fig. 6 is an elevation of a loop taker of modified construction;

Fig. 7 is a section on the line 'l--l of Fig. 6.

My improved loop taker, in the form illustrated in Figs. 1 to 5, comprises a hubor spider mem- A50 ber A, which is formed with an axial opening A in which the sewing machine rotary hook shaft (not shown) is normally secured. The member A is formed at its periphery with a forwardly extending rim or cylindrical flange A2 which in `55 the assembled condition of the loop taker, is

snuglybut removably received within the hook ring B, the latter being normally secured to the spider member A by screws C. The hook ring B is cut away at its front side to form the loop taking hook, or beak, B', and a hook notch B2, which comprises a, portion angularly in advance of the hook B', and a portion alongside the inner edge B3 of the hook. y

The hook ring notch B2 is bridged by an arc shaped part E normally having its ends received 10 in recesses B4 and B5 formed in the outer side of the hook ring at opposite sides of the notch B2, the ends of the part E being detachably secured in said recesses by screws. The member E is shaped to provide a thread deflectingedge E 15 inclined relative to a plane transverse to the loop taker axis, at an angle opposite to that at which the rear edge B3 of the loop hook B' is inclined. The member E also comprises an integral loop discharging spur E2, facing and adjacent the hook B', but having its point angularly '20 in advance of the point of the hook, having reference to the direction of the rotative movement of the hook. As is shown in Fig. 1A, the innerside o-f the base portion of the tapered spur E2 is well to the innerside of the hereinafter mentioned bearing rib D of the bobbin carrier D, so that the spur E2 is adapted to hold a thread loop engaging the innerside of its base portion out of engagement with said bearing rib D.

The formation of the loop deflector E and discharging spur E2 by integral portions of a part detachably connected to loop taker body or hook ring contributes to mechanical simplification and reduced manufacturing cost. The constructionV illustrated is advantageously characterized, moreover, by special provisions for accurately securing the part E in place on the hook ring and for guiding the thread at points where the edge E and spur E2 merge into thread engaging edge portions of the hook ring. Thus at the rear end 40 of the loop deecting edge E', having reference to the direction of looper rotation, the member E is formed with an inwardly extending lug E3, which has its inner end received in an opening B6 formed in the bottom Wall of the recess B5, and defines a loop receiving throat. Adjacent its forward end, the member E is formed with an inwardly extending flange portion E4, which constitutes a front side portion of the spur E2. The forward end of the flange E4 extends into a radial kerf Brl formed in the forward edge o-f the notch B2.

The front side of the flange portion E4 is thus disposed to the rear of the front edge portion 56 B10 of the hook ring which is angularly in advance of the notch B2, as clearly appears in Fig. 1A. In consequence, as the hook moves into the position at which a loop is being discharged, from the spur E2, the limb of that loop which, as a result of the loop taker movement, passes out of engagement with the edge B10 and into engagement with the portion E4 of the spur E2, has no opportunity to be caught by any corner or edge of the member E. With the integral portions E3 and E4, adjacent the opposite ends of the member E, thus received in openings formed for the purpose in the hook ring B, the member E is accurately and securely anchored in place and the adjacent thread guiding surfaces of the member E and hook ring B are properlyl related.

The front edge of the hook ring B is extended to form a loop throw oi shoulder B8' which trails the hook B and terminates about 180 back of the hook. Adjacent its front side, the hook ring is formed with an inwardly extending circumferential flange B9 alongside, but spaced away from the front end of the rim portion A2 of the hook spider A. The groove-like space thus provided between the end of the flange A2 and flange or shoulder-B9, is open at its innerside, and receives the peripheral guide flange D of the non-rotatable bobbin carrier D about which a needle thread loop is carried by the hook B in each stitch forming operation. The bobbin carrier D as shown, comprises a central post D2 on which the usual bobbin (not shown) is mounted. The bobbin carrier D is also formed at its front side with a pair of radially extending thread deflecting flanges D3 and D4 which extend radially outward beyond the peripheral edge of the ilange D', each for a considerable angular distance about the axis of the bobbin carrier. The adjacent end of the anges D3 and DL1 are spaced apart to form a notch receiving a nger part (not shown) for holding the carrierV against rotation and with its needle opening above the axis of the post D2.

The bobbin carrier D is not novel, but on the contrary, is of a type and form which is now and long has been in extensive commercial use. While no novelty is claimed in the form or construction of the carrier D, my improved loop taker is characterized by provisions permitting such a bobbin carrier of given size to'be used in a loop taker including separable hook ring and spider parts, smaller in diameter' than would be required but for said special provisions.

The latter consists of notches B10 and B11 formed in the innerside of the hook ring member B, which extend in the general direction of, and are located at the opposite sides of the axis of the hook ring. The notch B10 is formed in the portion of the hook ring at the rear of the hook notch B2. The notch B11 is formed in the flange B9,

and as shown, is of a depth approximately equal to the radial extent of said flange.

With the notches B10 and B11 arranged as shown, it is possible to warp the bobbin carrier D, as shown in Fig. 4, into and out of its normal position within the hook ring B, when the latter is disconnected from the spider A, without requiring the main cylindrical inner surface Yof the hook ring to have a diameter signicantly greater than that of the carrier Yrib D. The fact that the notch B10 is at the rear of the hook notch B2,

.is advantageous since, as shown in Fig. 2, the

cylindrical inner surface of the member E which bridges the notch B2, is farther fromthe axis of the hook ring than is the bottom of the notch B10.

carrier D.

- quired for the separate formation of hook ring and spider parts of the general character of the parts B and A, than is required for the production of a loop taker includingv corresponding parts integrally connected. While the advantages of the loop taker comprising separately formed hook ring and spider parts have long been recognized, the commercial use of such loop takers has been restricted, because of the practical difliculties in the way of mounting a suitable bobbin carrier in the loop taker and of providing the latter with thread deflecting or controlling parts corresponding to applicants parts E, E2, and B8, and suitably disposed and of suitable strength without making the loop-taker signicantly larger than it needs toy be when its hook ring and spider portions are integral, or when the loop taker is constructed as herein provided for. Y

While all the novel features of the present invention are adapted for conjoint use in a loop taker comprising separable hook ring and spider parts as shown in Figs. 1-5, the detachable member E, with its loop deflecting edge E and the loop discharging spur E2, may be used in a loopl taker, AB, as illustrated in Figs. 6 and 7, having integrally connected hook ring and spider portions. As the general construction of the loop taker AB forms no part of the present invention and is well known, it need not be described herein. It is noted, however, that lin such a loop taker, the bobbin carrier D is removably secured in operative relation to the loop taker AB, by means of a retaining ring F secured by screws F against a surface of the member AB transverse to the axis of the latter. in the assembled condition of the loop taker shown in Figs. Gand '7, the ring F forms the front wall of the annular .groove in the loop taker receiving the rib D of the bobbin In rthe construction shown in Figs. 6 and r1,'the ends of the loop taker E are secured to a cylindrical portion AB' of the member AB just as they are secured to the hook ring B of the construction first described, the member AB being formed with an opening B0 for the projection E3 and with a groove B", like the opening B5 and groove B7 previously described.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is: f

l. A new article of manufacture comprising a one piece metallic part adapted for attachment to the hook ring portion of a rotary hook sewing machine in bridging relation with the hook notch thereof, and comprising a body portionV having an inclined front edge portion adjacent one end adapted to form `one side of a thread loop receiving throat having its other side formed by the hook portion of said-hook ring and formed at its other end with a loop discharging spur adapted to deilect rearwardly the limb of a thread loop lili passing out of engagement with the rear edge of said hook in the nal portion of a stitch forming operation.

2. `A new article of manufacture comprising a one piece metallic part adapted for attachment to the hook ring of a rotary hook sewing machine in bridging relation with the hook notch thereof and comprising a body portion of cylindrical arc form and having an inclined front edge portion adjacent one end and adapted to form one side of a thread loop receiving throat having its other side formed by the hook portion of said hook ring and formed at its other end with a loop discharging spur adapted to deflect rearwardly the limb of a thread loopv passing out of engagement with the rear edge of said hook in the final portion of a stitch forming operation, said part also comprising an inwardly extending flange portion at the front edge of its said other end constituting a portion of said spur.

3. A rotary loop taker for a sewing machine comprising a hook ring portion formed with a.

hook and hook notch, and a part detachably connected to said ring portion in bridging relation with said notch, and formed with a front edge portion alongside and at the rear of said hook and uniting with the latter to form a thread loop limb receiving throat, andformed adjacent its opposite end with a loop discharging spur facing said hook and adapted to deflect rearwardly the said thread loop limb when the latter moves away from the hook in the final portion of the stitch forming operation in which said loop is formed.

4. A rotary loop taker for a sewing machine comprising a hook ring portion formed with a hook and hook notch, and a part detachably connected to said ring portion in bridging relation with said notch and formed with a front edge portion alongside and at the rear of said hook and uniting with the latter to form a thread loop limb receiving throat and formed adjacent its opposite end with a loop discharging spur facing said hook and adapted to deflect rearwardly the said thread loop limb as the latter is moved away from the hook in the final portion of the stitch forming operation in which said loop is formed, said part being formed with an inwardly extending flange portion forming the front side of said Vspur and said hook ring portion being formed with a radially extending groove opening from the edge of said notch adjacent the base of said spur and adapted to receive a portion of said flange.

5. A loop taker for a rotary hook sewing machine comprising an annular hook ring part formed with a hook notch, and with a hook at its front edge, and with an inwardly extending circumferential flange adjacent its front edge,

and a rhub part including a cylindrical .portion adapted to extend into and be detachably secured within said hook ring with the front edge of said cylindrical portion spaced away from they said flange to form a circumferential guideway, a non-rotatable bobbin carrier formed with a peripheral guide rib adapted to be received in said guideway and formed with a thread guiding portion at its front side overlapping said flange when said rib is received in said guideway, said ring being formed with diametrically opposed internal notches, one of which extends irough said flange, whereby when said hook ring and said hook part are separated, said carrier may be moved into and out of the position in which said thread guiding portion is in front, and said rib at the rear of and alongside said flange.

6. A loop taker for a rotary hook sewing machine comprising an annular hook ring partA formed with a hook notch, and with a hook at its front edge, and with Van inwardly extending circumferential ange adjacent its front edge, and a hub part including a cylindrical portion adapted to kextend into and be detachably secured within said hook ring with the front edge of said cylindrical portion spaced away from the said flange to form a circumferential guideway, a non-rotatable bobbin carrier formed with a peripheral guide rib adapted to be received in internal notches, one of which extends rear" Wardly from the front edge of the portion of the hook ring at the rear of said'notch and the other of which extends through said flange, whereby when said hook ring and said hook part are separated, said carrier may be moved into and out of the position in which said thread guiding portion is in front and said rib at the rear of and alongside said flange. l

V'7. An article of manufacture consisting of an annular one piece part, adapted for use as a detachable hook ring part of the loop taker of a rotary hook sewing machine, and formed with an inner cylindrical surface adapted to receive and snugly surround the peripheral portion of rthe hub port of the loop taker, and formed with ing a front edge portion extending away froml the base of said hook and diverging away from the plane of rotation of the hook to form a thread deflect or.

RICHARD K. HOHMANN.