US3507237A - Bobbin case opener for rotating looptaker lockstitch sewing machines - Google Patents

Bobbin case opener for rotating looptaker lockstitch sewing machines Download PDF

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Publication number
US3507237A
US3507237A US748549A US3507237DA US3507237A US 3507237 A US3507237 A US 3507237A US 748549 A US748549 A US 748549A US 3507237D A US3507237D A US 3507237DA US 3507237 A US3507237 A US 3507237A
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Prior art keywords
looptaker
bobbin case
finger
eccentric
opener
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US748549A
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English (en)
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Kristen Hedegaard
Franz Schneider
Herbert Wenz
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GM Pfaff AG
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GM Pfaff AG
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    • D—TEXTILES; PAPER
    • D05—SEWING; EMBROIDERING; TUFTING
    • D05B—SEWING
    • D05B57/00—Loop takers, e.g. loopers
    • D05B57/26—Bobbin holders or casings; Bobbin holder or case guards; Bobbin discharge devices
    • D05B57/265—Bobbin holders or casings; Bobbin holder or case guards; Bobbin discharge devices for looptakers with vertical axis

Definitions

  • a lockstitch sewing machine having a rotating looptaker cooperating with a reciprocatory needle operated by the main drive shaft, said looptaker rotating at a speed equal to a whole number multiple of the speed of said shaft, and a bobbin case frictionally mounted in said looptaker and restrained against rotation thereby by a tongue of said case engaging a stationary abutment
  • the escape gap for the needle thread loop between said tongue and abutment is opened during the loop-seizing revolutions only of the looptaker by a bobbin case opener intermittently rotating said case in the direction opposite to the looptaker rotation by an opening finger engaging a shoulder of said case along a predetermined operating path.
  • the operating path of the finger is composed ow two coordinate radial and rotational component oscillating movements of said opener derived through separate driving eccentrics, respectively, from the looptaker and main drive shafts.
  • the shape of said path is controlled by the relative adjustment of the eccentrics upon their respective drive shafts.
  • the present invention relates to rotating looptaker lockstitch sewing machines, more particularly to improved mechanism for the operation of the bobbin case opener forming part of machines of this type and serving to enable a ready passage of the needle thread loop, during the loop-seizing and casting revolutions of the looptaker, through the escape gap between the conventional rotationrestraining tongue of said case and a stationary abutment or notch provided upon the underface of the bed or clothplate of the sewing machine, said tongue being continuously urged, during rotation of the looptaker, against said abutment by the bobbin case being frictionally mounted in the looptaker.
  • a bobbin case opener operated by an opening member embracing an eccentric mounted upon the looptaker shaft, said member having an opening finger adapted to cooperate with a peripheral shoulder upon the bobbin case, to rotate the same in a direction opposite to the direction of rotation of the looptaker, in such a manner as to intermittently open said gap and to allow of a ready escape of the needle thread loop by the upward pull of the thread take-up during each stitch-forming cycle of the sewing machine.
  • the opening of the needle thread escape gap is effected by the finger of the bobbin case opener operated by the eccentric engaging a peripheral shoulder upon the bobbin case, to rotate said casein a direction opposite to the direction of rotation of the looptaker.
  • the rotationrestraining tongue is impinged against the opposite abutment wall of the rotation-restraining notch, whereby to result in an ever increasing impact or recoil force as the sewing speed is increased.
  • This results in an undesirable metallic noise, in a substantial heating of the parts, as well as other defects and drawbacks well understood.
  • uncontrollable natural oscillations or vibrations of the bobbin case may occur as the speed is increased, liable to greatly interfere with the sewing and stitch-forming operation. Under certain conditions, such oscillations may result in the cutting of the needle thread by a continued hammering efiect thereon by the restraining tongue vibrating between the walls of the restraining notch.
  • an important object of the present invention is to improve the referred to mechanical bobbin case opener, to substantially eliminate or minimize the afore-mentioned and related difficulties and defects, more particularly, to reduce the impact noise produced by both the rotation-restraining tongue and bobbin case operating finger, especially at the higher sewing speeds, to minimize the recoil force on the tongue upon hitting the wall of said notch, and finally to impede or prevent the setting up of uncontrollable oscillations of said tongue and in turn vibrations of the bobbin case, respectively.
  • FIG. 1 is an elevation of a rotating looptaker lockstitch sewing machine suitable for structural embodiment therein of the improved bobbin case opener according to the invention
  • FIG. 2 is a perspective view illustrating a first embodiment of the improved bobbin case opening device constructed in accordance with the principles of the invention
  • FIG. 3 is a sectional view, on an enlarged scale, taken on line IIIIII of FIG. 2;
  • FIG. 4 is a plan View of a second embodiment of the invention, the looptaker part thereof being shown in section taken on line IV-IV of FIG. 2; v I
  • FIG. 5 shows, on a greatly enlarged. scale, the composite operating path of the opening finger of the bobbin case opener according to the invention in relation to the shoulder upon the bobbin'case operated by said finger;
  • FIG. 6 is an elevation, shown partly in section, of a third constructional embodiment of a bobbin case opening device according to the invention.
  • FIG. 7 is a sectional view taken on line VII-VII of FIG. 6;
  • FIG. 8 isa view similar to FIG. 7, showing still another practical embodiment for the carrying into effect of the invention.
  • the present invention has set itself the task to elfect a continuous force-locking control of a bobbin case opener of the referred to'type by the provision of a predetermined and positive control of the opening finger, in such a manner as to cause an opening of the needle thread escape gap during the loop-' seizing revolutions only of the looptaker within a complete stitching cycle, or main driveshaft revolution of the machine, and to effect a relatively gradual opening yet rapid closing of said gap upon passage therethrough of the needle thread by the pull of the thread take-up, in an efiort'to reduce the impact force by said finger upon the walls of the bobbin case rotation-restraining notch.
  • the invention essen tially solves the foregoing problems by the utilization of two eccentric drives for a bobbin case opener of the referred to type, one of said drives operating in synchronism with the looptaker and the other drive operating in synchronism with the main drive shaft of the sewing machine.
  • the first driving eccentric is driven at a speed equal to a whole number multiple of the speed of the second eccentric conforming with the ratio of the loop-seizing and idle revolutions of the looptaker during a complete stitching cycle, that is, a one to one ratio for most conventional machines.
  • Both said eccentrics are furthermore adjusted relative to one another, in such a manner as to cause the finger of the bobbin case opener to engage the shoulder of the bobbin case during the loop seizing revolutions only of the looptaker, on the one hand, and to cause said finger to initially relatively gradually engage said shoulder, for the opening of the needle thread escape gap, and to subsequently become relatively rapidly disengaged from said shoulder, after escape of the thread through said gap, on the other hand.
  • the component oscillating movement imparted to the bobbin case operating finger by the eccentric operating in synchronism with the looptaker shaft has superimposed upon it the component oscillating movement imparted to said finger by the eccentric operating in synchronism with the main drive shaft of the sewing machine, the relative phase of said movements being adjusted in such a manner that, during the idle or non-loop seizing revolutions of the looptaker, the opening finger is deflected to a limited extent only so as to be unable to contact the shoulder of the bobbin case, on the one hand, and that, during the loop-seizing revolotions of the looptaker, that is, the revolutions during which the looptaker beak seizes and casts the needle thread loop about the bobbin case, the opening finger is deflected or operated along a section of its operating path such as to first effect a gradual contact with said shoulder, for the gradual and smooth opening of the needle thread escape gap with a minimum of noise, and to thereafter effect a relatively quick or instant
  • the needle thread loop is enabled to pass about the bobbin case without substantial obstruction even at the highest sewing speed, while reducing or eliminating impact noise by the opening finger and restraining tongue and preventing other drawbacks and defects of the prior bobbin case opener constructions mentioned hereinabove.
  • eccentric drives of the bobbin case opener equivalent devices such as crank and link mechanisms
  • crank and link mechanisms may be used for the carrying into effect of the invention.
  • eccentric as used for the purpose of this specification and claims is, accordingly, intended to include such equivalents for the conversion of the rotary movements of the looptaker and main drive shafts into the respective bobbin case oscillating movements in accordance with the basic concept of the invention.
  • the second eccentric controlling the operating path of the opening finger of the bobbin case opener and being driven in synchronism with the main drive shaft is advantageously adjustably mounted upon its shaft, to enable a control of the shape of said path, to suit existing operating conditions or requirements.
  • the numeral 1 indicates the bed or clothplate of a conventional flat-top sewing machine, said bed carrying a housing 2 composed in a known manner of an upright and overhanging arm, the latter terminating in a sewing head and having supported therein the main drive shaft 3 of the machine.
  • Shaft 3 carries, at its outwardly projecting rear end, a hand wheel 4 and is fitted, at its opposite or front end with a crank 5 which serves to operate, by way of a link 6, the needle bar 7 mounted for vertical reciprocation in the head of the machine and carrying a needle 8- at its lower end.
  • the rotary hook or looptaker drive shaft 9 mounted vertically, in the example shown, and operably connected with the main drive shaft 3 in any suitable manner, such as via a chain belt 10 co operating with a pair of driving and driven chain wheels of like diameter 11 and 12, respectively.
  • a mounting support or bracket 13 secured to the underside of the bed 1 is a mounting support or bracket 13, FIGS. 1 and 2, supporting the looptaker and in the front wall of which is journalled the leading end of the looptaker drive shaft 9.
  • Support 13 includes a horizontal intermediate wall 15 in which is mounted the looptaker assembly collectively denoted by 16 in FIG. 2.
  • the sewing machine may be equipped with a four-motion or the like feed dog (not shown) for the production of lockstitches in the work being operated on by cooperation of the upper thread-carrying needle 8 with the underthread-carrying looptaker 16, in a manner well known to those skilled in the art.
  • the looptaker assembly 16 comprises, in the example shown, a hollow looptaker shaft 17, FIG. 3, carrying, at its upper end, the looptaker 18 and having its outwardly threaded lower end secured, through an internally threaded cylindrical bush 19 and by means of a connecting screw or bolt 20, to a bevel gear 21.
  • Bevel gear 21 meshes with further bevel gear 22 being fast on the looptaker drive shaft 9.
  • bevel gear 22 has twice the diameter of the bevel gear 21, whereby the shaft 17 of the looptaker 18 rotates at twice the speed of the drive shaft 9, or main shaft 3, respectively.
  • the looptaker 18 performs two revolutions during each stitching cycle or complete reciprocation of the needle 8, in accordance with the operation of conventional rotary looptaker sewing machines.
  • the bevel gears 21 is designed for a corresponding speed relative to the gear 22.
  • a bobbin case 24 having a peripheral rib journalled in a corresponding guide groove in the interior surface of the looptaker of conventional construction.
  • a snap cover or cap 26 secured in place by means of a pivoted locking lever 27.
  • the bobbin case which in a known manner houses the bobbin containing the underthread, is fitted upon its periphery ith a rotation-restraining tongue.
  • the bobbin case 24 being normally urged, by friction with the looptaker, against One of the walls of the notch 30, that is, the Wall spaced from said tongue in the direction of looptaker rotation, is limitative rotatable relative to the looptaker, that is, within the walls or abutments of the notch 28.
  • the upper end of the looptaker shaft 17 has the form of an eccentric 31 fitted upon its upper face with follower pins 32 which project into corresponding recesses in the looptaker bottom 18.
  • an eccentric ring 35 cooperating with the eccentric 31, by way of a ball bearing 34, is an eccentric ring 35 having an eccentric arm 39 and acting as a bobbin case opener in the manner described and explained in greater detail in the following in reference to FIGS. 2, 3, 4 and 6.
  • the ring or opener 35 is fitted with a peripheral upwardly extending control finger 36 angularly bent at its upper end and adapted to cooperate with a projection or shoulder 37 upon the periphery of the bobbin case 24, to intermittenly rotate the latter in a direction opposite to the rotation of the looptaker 18 and to thereby open the needle thread escape gap between the tongue 28 and its abutment wall of the notch 30.
  • This will allow of a ready passage of the needle thread during its upward .pull by the thread take-up of the sewing machine in the course of a stitch-forming operation or cycle.
  • the entire looptaker assembly 16, together with the ball bearings 233, is mounted by press-fit enegagement or otherwise in the wall or bracket of the support 13 and secured against axial displacement by means of a cover or washer 38, FIGS. 3 and 6, applied to the outer ring of the ball bearing 23.
  • an intermediate member 46 to which is linked, by means of a tapped pin 47, the end of an eccentric arm 48 whose opposite ringshaped end embraces an eccentri 49 adjustably mounted, in any suitable manner, upon the looptaker drive shaft 9, whereby to be rotated in synchronium with the main drive shaft 3.
  • the linkage mechanism of FIG. 2, connecting the eccentric 49 with the bobbin case opener 35 and comprising the eccentric arm 48, push rod 45 and link 41 is replaced by a link 51 having one end rotatively connected, by means of a pin or bolt 50, to the eccentric arm 39 of the bobbin case opener 35, with the opposite end of the link 51 embracing the eccentric 49.
  • the latter is preferably adjustably mounted upon the end of a vertical shaft 52 being spaced from and parallel to the looptaker shaft 17 and suspended from the bed 1 of the machine.
  • a first bevel gear 53 Secured to the shaft 52 is a first bevel gear 53 which meshes with a second bevel gear being of equal size 54 to the gear 53 and fast upon the looptaker drive shaft 9.
  • the shaft 52 and eccentric 49 rotate with the same speed as the main drive shaft 3.
  • the driving eccentric 49 of the bobbin case opener according to FIG. 4 is adjustably mounted upon a shaft 56 supported by the bracket 13 and secured against axial displacement by means of a setting ring 55.
  • the axis of rotation of the shaft 56 coincides with the axis of the looptaker shaft 17 and carries at its upper end a bevel gear 57 meshing with an equal-sized bevel gear 58 fast on the looptaker drive shaft 9.
  • the eccentric 49 cooperates with the ring-shaped end of an eccentric arm 59 whose opposite end is rotatively connected, by means of a pin 60, to a crank 61 secured to a vertical shaft 62, the latter being journalled in the support 13 and carrying at its upper end a further crank 63.
  • Both cranks 61 and 63 form an angular lever 64 rotatable about the shaft 62 and secured against axial displacement by means of a setting ring 65.
  • Rotatively connected, by means of a pin 66, to the crank 63 is an end of a link 67 whose opposite end is in turn rotatively connected, by means of a pin 68, to the eccentric arm 39 of the bobbin case opener 35.
  • the bobbin case opener 35 is replaced by a pull rod or bar 69 having one (ring-shaped) end mounted upon the eccentric 31 of the looptaker shaft 17 and having its free end rotatively connected, by means of a pin 70, to the end of a link 71 whose opposite ring-shaped end embraces the driving eccentric 49.
  • the link 71 is extended in the opposite direction from its pivot 70 as shown in 72 and bent at its free end to act as bobbin case opening finger 36 for cooperation with the bobbin case shoulder 37, in the manner as described hereinbefore.
  • a separate opening finger may be connected to the extension arm 72.
  • the eccentric 49 is mounted upon a vertical shaft 73 journalled in the support 13 and driven by a bevel gear pair 74 and 75 by and in synchronism with the looptaker drive shaft 9.
  • Rotation of the main drive shaft 3 by a conventional driving motor causes the needle bar 7 to be reciprocated in a vertical direction by the crank 5 and link 6, whereby the needle 8 affixed to the lower end of the bar 7 cooperates with the looptaker 18 driven, by way of belt 10, Wheels 11, 12, looptaker drive shaft 9 and bevel gear pair 22-21, to rotate twice per revolution of shaft 3 or each complete reciprocation of the needle 8, for the formation of lockstitches in the work being operated on.
  • the needle thread loop seized by the looptaker beak is cast about the bobbin case 24, more particularly, by the work limb of said loop being led over the undersurface and by the needle limb of said loop passing over the upper face of the bobbin case 24.
  • the bobbin case opener 35 As a consequence, the bobbin case opener 35 according to the first, second and third embodiments described in the foregoing, being mounted, via the ball bearing 34, upon the eccentric 31 rotating in synchronism with the looptaker 18, has imparted to it, during the operation of the machine and by virtue of the connection, by means of pin 42, of the arm 39 of member 35 to the link 41 (first embodiment), or to the link 51 by means of pin 50, (second embodiment), or finally to the link 67 by means of pin 68 (third embodiment), respectively, a continuous radial oscillating movement in respect to the looptaker shaft or axis 17, to which component movement is added a rotational oscillating component of the bobbin case opener 35 about the eccentric 31 in synchronism with the rotation of the main drive shaft 3 and by way of the eccentric 49, eccentric arm 48, clamping member 46, slide rod 45, clamping member 44 and link 41 (first embodiment), or by way of link 51 (second embodiment), or by way of the eccentric arm 59, angular
  • FIG. 8 there is imparted to the end or finger 36 of the extension 72 of link 71, said finger cooperating with the shoulder 37 on the bobbin case, a first oscillating component movement about the eccentric 49 upon shaft 73 and by way of the pull bar 69 embracing the eccentric 31, on the one hand, and being connected to link 71 by the pin 70, on the other hand.
  • a further oscillating component derived from the eccentric 49 rotating in synchronism with the looptaker drive shaft 9, said further component being directly imposed upon the link 71 by its end embracing the eccentric 49.
  • the mutual adjustment of the driving eccentrics 31 and 49 of the bobbin case opener 35 is such, in accordance with the basic concept of the present invention, that the finger 36, or a point thereof, respectively, follows a resultant predetermined course or operating path, per each revolution of the main drive shaft 3 or stitch-forming cycle of the machine and by superimposition of both driving movements of the eccentrics 31 and 49, rotating at different speeds, as shown by FIG.
  • said composite operating path comprising the successive sections A (between points and 4), B (between points 4 and 5), C (between points 5 and 6), and D (between points 6 and 12 or 0).
  • sections B and C engage or intersect the edge of the shoulder 37, section B having a relatively small curvature towards said shoulder and section C having a substantially greater curvature in the opposite direction or away from the shoulder 37.
  • the finger 36 follows, during the loop-seizing and casting revolutions of the looptaker 18, a path comprising the sections A, B and C shown by full lines in FIG. 5, while the path of the finger 36 during the alternate or idle looptaker revolutions follows the curve or section D indicated by the dotted line in the drawing.
  • the finger 36 engages the shoulder 37 of the bobbin case 24 during the loop-seizing revolutions of the looptaker 18 only.
  • the bobbin case 24 is operated by the finger 36 in the direction opposite to the direction of rotation of the looptaker during every second looptaker revolution only, to allow of the escape of the needle thread loop through the gap formed by the rotation-restraining tongue 28 and the abutment wall of the notch 30.
  • the shoulder 37 is released from the finger 36, thus allowing the bobbin case to return to its operative position or position of engagement between the tongue 28 and wall of the notch 30 spaced from the tongue in the looptaker rotating direction.
  • the finger 36 engages the shoulder 37 at a point within section B of the operating path, that is, approximately at point 4 of said path.
  • section B has a relatively small curvature towards the shoulder 37 (between points 4 and 5), with the result that the finger initially engages the shoulder at a relatively low speed and wiping engagement therewith, whereby to reduce its impact upon the shoulder to a minimum.
  • the bobbin case 24 is rotated relatively slowly or gradually in the direction opposite to the direction of rotation of the looptaker 18.
  • the recoil force upon the tongue 28 is reduced to a minimum, substantially preventing thereby the setting-up of uncontrollable natural oscillations of the case 24, as Well as damage to or breakage of the thread by the impact of the tongue 28 upon the walls of notch 30.
  • the impact force of the finger 36 upon the shoulder 37 is reduced or minimized in the manner pointed out, thus substantially eliminating undesired noise and other defects during high sewing or operating speeds.
  • the section B of the operating path of the finger 36 of relatively small curvature is followed at point 5 by the section C of greater curvature in the opposite direction or away from the shoulder 37. While passing through the section C the finger 36 acts to instantly and quickly release, immediately after the escape of the needle thread from the gap between the tongue 28 and abutment wall of the notch 30, the shoulder 37 of the bobbin case 24, allowing thereby the needle thread loop to safely and readily pass about the bob-bin case 24.
  • the finger 36 by the actions of its first driving eccentric 31, operating in synahronism with the looptaker 18, and of its second driving eccentric 49, operating in synchronism with the main drive shaft 3, perform an idle movement or oscillation during each revolution of the shaft 3 or stitch-forming cycle, respectively, as indicated in dotted line by the section D, that is, the finger 36 does not engage the shoulder 37 during the idle revolution or executes an operative movement along sections B-C solely during the loopseizing and casting revolutions of the looptaker, for the opening of the needle thread escape gap between the tongue 28 and abutment 30, in the manner described hereinbefore.
  • This results in a further reduction of impact noise, aside from the smooth operation of the opener during the operative (loop-seizing) looptaker revolutions, enabling thereby the machine to be safely operated at substantially high sewing or operating speeds.
  • the shape of the path of the opening finger 36 may be varied, within certain limits, by a mutual adjustment of the eccentrics 31 and 49 upon their respective driving shafts, to suit any existing operating conditions or requirements.
  • it is sulficient to provide for setting or adjusting the eccentric 49 upon is driving shaft, that is, shaft 9 (FIG. 2), shaft 52 (FIG. 4), shaft 56 (FIG. 6), and shaft 73 (FIG. 8).
  • the shape of the operating path of the finger 36, FIG. 5 is predicated in the first place on the different driving speeds of the eccentrics 31 and 49, resulting in the change of the extent of the path during alternate revolutions of the opener, as indicated by the full and dotted lines, respectively, in the drawing, and, in the second place, upon the mutual phase or adjustment of the eccentrics relative to their respective drive shafts, to control the angle of attack of the finger, or curvature of the path sections B and C, in the manner and for the purpose as described hereinbefore.
  • a lockstitch sewing machine having a reciprocatory needle, a main drive shaft with means to reciprocate said needle once during each revolution of said shaft, a rotary looptaker having a looptaker shaft wtih means to rotate the same by said main drive shaft at a speed being a whole number multiple of the speed of said main drive shaft, and a bobbin case frictionally mounted in said looptaker and having a shoulder and a rotationrestraining tongue, a stationary abutment, said rotationrestraining tongue engaging said stationary abutment, a bobbin case opener including means to intermittently open a needle thread escape gap between said tongue and abutment, comprising in combination:
  • a bobbin case opener as claimed-in claim 1 said first and second eccentrics being adjustable relative to one another such as to cause said finger to engage said shoulder during the loop-seizing revolutions only of said looptaker.
  • a bobbin case opener as claimed in claim 1 said first and second eccentric being adjustable relative to one another to result in a predetermined composite operating path of said finger by superimposition of said first and second component movements, whereby to cause said finger, during the loop-seizing revolutions of said looptaker, to initially relatively gradually engage said Shoulder, to result in a slow opening of said gap, and to become subsequently relatively rapidly disengaged from said shoulder accompanied by a quick opening of said gap.
  • a bobbin case opener as claimed in claim 1 said opening finger being fast upon and extending from said member.
  • a bobbin case opener as claimed in claim 1 said motion-transmitting means comprising first and second connecting arms each having an end embracing, respec tively, said first and second eccentric and having their remaining ends connected by said pivot, said opening finger forming an extension of said second connecting arm.
  • a bobbin case opener as claimed in claim 1 said motion transmitting means comprising a slidably mounted push rod operably connected, respectively, through a pair of links to said member and an eccentric arm of said second eccentric.
  • a bobbin case opener as claimed in claim 1 wherein both said eccentrics are coaxial with said looptaker drive shaft and wherein said motion-transmitting means consists of a two-arm angular lever journalled upon a stationary shaft and connected by a link and ecentric arm, respectively, to said member and said second eccentric.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Sewing Machines And Sewing (AREA)
US748549A 1967-07-31 1968-07-29 Bobbin case opener for rotating looptaker lockstitch sewing machines Expired - Lifetime US3507237A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114717760A (zh) * 2021-01-05 2022-07-08 杰克科技股份有限公司 一种缝纫机中的旋梭开梭机构及缝纫机

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3244946C1 (de) * 1982-12-04 1984-04-26 Pfaff Industriemaschinen Gmbh, 6750 Kaiserslautern Freiumlaufender Greifer fuer Doppelsteppstichnaehmaschinen
JP4455175B2 (ja) 2004-06-08 2010-04-21 Ｊｕｋｉ株式会社 ミシンの水平釜のオープナー

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1728506A (en) * 1927-08-11 1929-09-17 Singer Mfg Co Guard for sewing-machine loop takers
US1763670A (en) * 1929-01-15 1930-06-17 Singer Mfg Co Loop-taker mechanism for sewing machines

Family Cites Families (2)

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Publication number Priority date Publication date Assignee Title
US2095450A (en) * 1936-04-16 1937-10-12 Singer Mfg Co Sewing machine loop-taker mechanism
GB764785A (en) * 1954-03-04 1957-01-02 Singer Mfg Co Rotary loop-taker mechanism for sewing machines

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1728506A (en) * 1927-08-11 1929-09-17 Singer Mfg Co Guard for sewing-machine loop takers
US1763670A (en) * 1929-01-15 1930-06-17 Singer Mfg Co Loop-taker mechanism for sewing machines

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114717760A (zh) * 2021-01-05 2022-07-08 杰克科技股份有限公司 一种缝纫机中的旋梭开梭机构及缝纫机

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