US3804038A - Sewing machine braking mechanism - Google Patents

Sewing machine braking mechanism Download PDF

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Publication number
US3804038A
US3804038A US00370720A US37072073A US3804038A US 3804038 A US3804038 A US 3804038A US 00370720 A US00370720 A US 00370720A US 37072073 A US37072073 A US 37072073A US 3804038 A US3804038 A US 3804038A
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US
United States
Prior art keywords
shaft
operating lever
brake
lever
abutment
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00370720A
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English (en)
Inventor
A Martin
E Albrecht
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Pfaff Industriemaschinen GmbH
Original Assignee
Pfaff Industriemaschinen GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Pfaff Industriemaschinen GmbH filed Critical Pfaff Industriemaschinen GmbH
Application granted granted Critical
Publication of US3804038A publication Critical patent/US3804038A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • D—TEXTILES; PAPER
    • D05—SEWING; EMBROIDERING; TUFTING
    • D05B—SEWING
    • D05B69/00—Driving-gear; Control devices
    • D05B69/22—Devices for stopping drive when sewing tools have reached a predetermined position

Definitions

  • the operating lever is held by a locking lever which may be released under the action of a control cam to permit displacement of the locking member out of the locking groove after the speed of the main shaft drops below a certain value.
  • the weights move inwardly toward the shaft and they engage with the holding collar which is returned to an engagement position by its associated spring after the locking lever'is moved'to a position permitting the operating lever to move out of engagement with the clutch disc stop groove.
  • sewing machines having an engaging and disengaging driving mechanism and a stopping device which comprises a braking means mounted on the main shaft of the machine and a stationary brake abutment which cooperates therewith is provided with a locking member engaging into a stopping groove as soon as the speed of the main shaft of the machine drops below a certain value.
  • the braking means which counteracts the force of a return spring, can be moved by centrifugal force against the brake abutment and for thispurpose, it is advantageously supported on a resilient element such as a spring which permits it to move outwardly under the influence of centrifugal force.
  • the braking force which depends on the square of the angular velocity of the main shaft becomes effective at the beginning of the braking operation and as soon as the main shaft is braked down to a speed which is harmless for applying a stopping device, which automatically drops the speed down to a zero value.
  • the main shaft still has a rotational energy necessary for one revolution.
  • the braking means is provided in the form of leaf springs which are mounted on collars so that they extend parallel to the main shaft and carry weights at their free ends which have lateral extensions cooperating with a recess provided in a control socket which may be axially shifted along the main shaft.
  • an object of the invention to provide an improved sewing machine which has a main drive shaft with an engaging and disengaging drive mechanism for driving the shaft and which has a clutch disc with a stopping groove which is engageable with a locking member after the machine is brought down to a predetermined speed and which also includes a braking mechanismin the form of a brake weight which is carried on a spring and biased outwardly toward en-- gagement with a stationary brake abutment, but which is held by a locking collar which is released when the locking member engages into the stopping groove.
  • a further object of the invention is to provide a sewing machine which is simple in design, rugged in construction and economical to manufacture.
  • the invention embodied therein comprises a sewing machine having a housing 1 with a main shaft 2 rotatably supported in the housing and in a position to drive a needle bar (not shown).
  • the shaft 2 carries a pulley 52 which drives a belt 3 and a pulley 53 carried on a lower shaft or control shaft 4.
  • the shaft 4 carries a worm 5- which drives a worm gear 5a of a shaft 6a having a gear 6 which drives a gear 617 to rotate a control disc 7.
  • the main drive shaft 2 is rotated by an engaging and disengaging driving mechanism which includes a clutch disc 8 which is secured to the shaft 2 for rotation therewith and which is rotated by a driving disc 9 which is freely mounted on the shaft 2 and which maybe shifted axially.
  • the drive disc 9 is formed integral with a V'beIt pulley which is driven by a V-belt 11 which is operated by a rotating motor (not shown).
  • a clutch ring 12 is rotatably mounted on a neck portion of the V-belt pulley 10 and it carries diametrically opposite parallel slots 13, 13 therein. Rollers 14 of an actuating fork 15 engage into the respective slots 13 and the actuating fork 15 is rotatable about a pivot 16 provided on the arm 17 of an operating lever 18.
  • the operating lever 18 is rotatable about a fixed pivot 19 and is connected to an intermediate lever 21 by means of a link 20.
  • One end of the intermediate lever 21 is rotatable about a fixed pivot 22 and the other end is hinged to a pull rod 23 whose lower end is connected to a pedal (not shown).
  • the operating lever 18 is held in its rest position by a spring 24 having one end which is attached to the link and an opposite end which is connected to the housing 1. In the rest position, the driving disc 9 and the clutch 8 are separated from each other and no rotation of the shaft 2 takes place.
  • a locking member 25 is carried at the upper end of the operating lever 18 and is adapted to engage into a stopping groove 26 of the clutch disc 8.
  • a retaining pawl 27 is provided on the operating lever 18 and it is adapted to engage into a stepped recess 28 of a spring-loaded locking lever 29 which is rotatably mounted on a fixed pivot 30 and connected to a cam lever 32 by means of tie rod 31.
  • the free end of the cam lever 32 cooperates with th series of stepped cams 33 provided on the main control disc 7.
  • a leaf spring support or mounting collar 34 is mounted on the shaft 2 and it is provided with slots 35 which extend axially in respect to the shaft 2 and are spaced circumferentially around the periphery of the support.
  • Each leaf spring 36 is mounted within a slot 35 and it has a free end which projects axially from the support and is loaded with a brake weight 37.
  • the brake weights 37 are provided with a brake lining 38 which forms braking means 39 cooperable with a fixed annular brake abutment 40.
  • the leaf springs 36 are biased by a certain amount so that their biasing force which is directed against the shaft 2 overbalances the centrifugal force acting on the weights 37, but only up to a certain speed of the main shaft which is referred to as the stopping speed.
  • each weight 37 is provided with an arc-shaped extension 41 which is adapted to engage into an annular recess 42 of a flanged control socket or collar 44 which comprises operating means generally designated 43.
  • the collar 44 is mounted so as to be axially shiftable on the main shaft 2 and it is held in an engaging relationship with the extension 41 of the weights 37 by means of a spring 45 which is anchored at one end against the abutment'l of the housing and has an opposite end which engages against the collar 44.
  • An actuating lever 46 is pivoted to the housing 41 and it provides means for shifting the control socket or collar 44.
  • the actuating lever 46 carries a roller 47 which cooperates with a lateral face of the control socket 44.
  • the lower end of the actuating lever 46 is provided with a pin 48 which extends through a slotted hole 49 of an intermediate lever 50.
  • a spring 51 is located between the actuating lever 46 and the intermediate lever 50 and establishes a frictional contact therebetween. The other end sition off the reach of the rotating clutch disc 8.
  • the control socket 44 looks the centrifugal weights 37 in their ineffective non-braking position.
  • the locking lever 29 is turned clockwise as shown in FIG. 1, through a predetermined angle through the action of the linkage 31, 32 in cooperation with the lower step of a cam 33 which is provided on the main control disc 7.
  • the retaining pawl 27 is disengaged from the lower step of the recess 28 and engages with the upper step of the recess 28.
  • the operating lever 18 is turned clockwise about the pivot 19.
  • the driving disc disengages from the clutch disc 8 and, through the intermediate lever 50 and the actuating lever 46, the control socket 44 is shifted along the main shaft 2 by a predetermined distance to the right, as shown in FIG. 2, against the force of the spring 45.
  • the extensions 41 of the centrifugal weights 37 thereby become released so that the weights can move outwardly against the biasing force of the leaf springs 36.
  • the brake lining 38 then applies against the fixed brake abutment 40 and brakes the main shaft of the machine down to a speed depending on the square of the angular output velocity of the main shaft 2.
  • the biasing forces of the leaf springs 36 exceed the centrifugal forces acting on the weights 37 so that the weights 37 are returned to their ineffective position.
  • the main shaft of the machine continues to rotate at the stopping speed.
  • a sewing machine comprising a main drive shaft, an engaging and disengaging driving mechanism for driving said main drive shaft having a disc with a stopping groove, a stopping device comprising a braking means arranged on said main drive shaft, spring means biasing said braking means inwardly, a stationary brake abutment surrounding said brake means and cooperating therewith, a locking member adapted to engage into the stopping groove as soon as the speed of the main shaft of the machine drops below a certain value and owing to the centrifugal effect, said braking means counteracting the force of said spring means and being movable against said brake abutment, and operating means associated with said braking means for holding it out of engagement with said abutment and for releasing said braking means for movement under the centrifugal force acting to engage said abutment.
  • said braking means comprises at least one weight and a leaf spring mounted on said shaft and holding said weight outwardly therefrom, said weight having an extension, said operating means including a control collar shiftable alongsaid shaft.
  • a sewing machine including a single control lever for effecting the starting and stopping of said shaft, an operating lever pivoted on said housing and carrying said locking member, said operating means being connected to said operating lever by a friction coupling having a displaceable idle stroke.
  • a sewing machine comprising a housing, a rotatable main needle drive shaft rotatably mounted in said housing, a stationary brake abutment supported in said housing adjacent said shaft, a centrifugal weight brake, a spring carried on said shaft and supporting said weight brake at its free end for movement outwardly of said shaft to contact said brake abutment by centrifugal force during rotation of said shaft beyond a predetermined speed, a control collar surrounding said shaft engageable with said weight brake and holding said brake towards said shaft and out of engagement with said brake abutment, a drive member secured to said shaft for rotation therewith and having a stop groove, an operating lever having a locking member engageable with said stop groove and being pivotally mounted on said housing, a locking lever having an engagement step engageable with said operating lever, a rotatable disc cam having cams thereon connected to said main shaft for rotation thereby, follower means engageable with said cams for displacing said locking lever to release said operating lever, said locking member of said operating lever being movable out of engagement with said
  • a sewing machine including a pull rod connected to said operating lever to operate said operatinglever and an intermediate lever connected between said operating lever and said control collar and having a lost motion engagement therewith so that said intermediate member is moved only after a predetermined movement of said operating lever.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Sewing Machines And Sewing (AREA)
  • Braking Arrangements (AREA)
US00370720A 1972-06-27 1973-06-18 Sewing machine braking mechanism Expired - Lifetime US3804038A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2231482 1972-06-27

Publications (1)

Publication Number Publication Date
US3804038A true US3804038A (en) 1974-04-16

Family

ID=5848965

Family Applications (1)

Application Number Title Priority Date Filing Date
US00370720A Expired - Lifetime US3804038A (en) 1972-06-27 1973-06-18 Sewing machine braking mechanism

Country Status (4)

Country Link
US (1) US3804038A (enrdf_load_html_response)
JP (1) JPS575555B2 (enrdf_load_html_response)
DE (1) DE2231482C2 (enrdf_load_html_response)
IT (1) IT986590B (enrdf_load_html_response)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4730565A (en) * 1986-04-28 1988-03-15 Tokyo Juki Industrial Co., Ltd. Stopping device for an eyelet button holing machine
US5460107A (en) * 1993-09-29 1995-10-24 Amf Reece, Inc. Roller activated stop motion mechanism for an eyelet buttonhole machine
USRE35626E (en) * 1986-04-28 1997-10-14 Juki Corporation Stopping device for an eyelet button holing machine
US5802999A (en) * 1997-01-06 1998-09-08 Amf Reece, Inc. Stop mechanism for a buttonhole sewing machine

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002186658A (ja) * 2001-10-01 2002-07-02 Yuyama Manufacturing Co Ltd 錠剤フィーダ
CN108223614B (zh) * 2017-11-28 2019-09-03 温州慧思工业设计有限公司 一种速度选择传动机构

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1422639A (en) * 1916-07-31 1922-07-11 Hamel Shoe Machinery Co Stop motion for shoe-sewing machines
DE655371C (de) * 1936-03-20 1938-01-14 Fusion Moteurs Kupplung, insbesondere fuer Schleudermaschinen
US2377037A (en) * 1940-03-26 1945-05-29 Franklin A Reece Sewing machine
US3077845A (en) * 1959-06-05 1963-02-19 Necchi Spa Control system for a sewing machine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1422639A (en) * 1916-07-31 1922-07-11 Hamel Shoe Machinery Co Stop motion for shoe-sewing machines
DE655371C (de) * 1936-03-20 1938-01-14 Fusion Moteurs Kupplung, insbesondere fuer Schleudermaschinen
US2377037A (en) * 1940-03-26 1945-05-29 Franklin A Reece Sewing machine
US3077845A (en) * 1959-06-05 1963-02-19 Necchi Spa Control system for a sewing machine

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4730565A (en) * 1986-04-28 1988-03-15 Tokyo Juki Industrial Co., Ltd. Stopping device for an eyelet button holing machine
USRE35626E (en) * 1986-04-28 1997-10-14 Juki Corporation Stopping device for an eyelet button holing machine
US5460107A (en) * 1993-09-29 1995-10-24 Amf Reece, Inc. Roller activated stop motion mechanism for an eyelet buttonhole machine
US5802999A (en) * 1997-01-06 1998-09-08 Amf Reece, Inc. Stop mechanism for a buttonhole sewing machine

Also Published As

Publication number Publication date
DE2231482C2 (de) 1974-05-16
JPS4967751A (enrdf_load_html_response) 1974-07-01
DE2231482B1 (de) 1973-10-11
JPS575555B2 (enrdf_load_html_response) 1982-01-30
IT986590B (it) 1975-01-30

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