US3744442A

US3744442A - Automatic bobbin changer

Info

Publication number: US3744442A
Application number: US00183538A
Authority: US
Inventors: S Michaels; F Darwin
Original assignee: Levi Strauss and Co
Current assignee: Levi Strauss and Co
Priority date: 1971-09-24
Filing date: 1971-09-24
Publication date: 1973-07-10
Anticipated expiration: 1990-07-10

Abstract

An automatic bobbin changer for sewing machines includes a cylindrical container for housing a plurality of bobbins in a circular array such that the uppermost bobbin may be utilized by a standard sewing machine in a conventional manner, a cycling mechanism for rotating the cylindrical container about its longitudinal axis to move a new bobbin into an operative position, a clutch-brake device positioned between a drive motor of the cycling mechanism and the sewing machine drive for declutching and braking the main drive of the sewing machine while the bobbin cylinder is being cycled and for disengaging the brake and reengaging the clutch after the bobbin has been cycled to resume sewing, and a control system for counting the stitches sewn from a particular bobbin and for actuating the cycling mechanism after a predetermined number of pieces have been sewn with a predetermined number of stitches in each and simultaneously operating the clutch-brake device.

Description

United States Patent 1 Michaels et al. v

11] 3,744,442 [451 July 10,1973

[ 4] AUTOMATIC BOBBIN CHANGER [75] Inventors: Sid Michaels; Frank Darwin, both of Knoxville, Tenn.

[73] Assignee: Levi Strauss & Co., San Francisco,

Calif.

22 Filed: Sept. 24, 1971 [21] Appl. No.: 183,538

[52] US. Cl. 112/186 [51] Int. Cl D05b 59/00 [58] Field ofSearch 112/186, 180

[56] References Cited UNITED STATES PATENTS 3,125,973, 3/1964 Berneru sa 112/186 FOREIGN PATENTS OR APPLICATIONS 721,975 l/1955 Great Britain 112/186 Primary Examiner--Werner H. Schroeder Attorney-NormanlF. Oblon et al.

[5 7] ABSTRACT An automatic bobbin changer for sewing machines includes a cylindrical container for housing a plurality of bobbins in a circular array such that the uppermost bobbin may be utilized by a standard sewing machine in a conventional manner, a cycling mechanism for rotating the cylindrical container about its longitudinal axis to move a new bobbin into an operative position,

-a clutch-brake device positioned between a drive motor of the cycling mechanism and the sewing machine drive for declutching and braking the main drive of the sewing machine while the bobbin cylinder is being cycled and for disengaging the brake and reengaging the clutch after the bobbin has been cycled to resume sewing, and a control system for counting the stitches sewn from a particular bobbin and for actuating the cycling mechanism after a predetermined num- I ber of pieces have been sewn with a predetermined number of stitches in each and simultaneously operatingthe clutch-brake device.

10 Claims, 13 Drawing Figures Pmsmenwu 3.744.442

sum 1 or 6 4 INVENTOR SID MICHAELS mm? Maw aY/afa f ATTORNEYS mmnmuuom x i 3,744,442

sum 3 or s FIG. l

PAIENTEDJUL 1 0 1w SHEEI HIFG PAIENIEUJULIOIQH 744442 sum 5 or e I 88 CLUTCH-BRAKE COUPLING AUTOMATIC BOBBIN CHANGER This invention relates generally to sewing machines and more particularly -to an apparatus for automatically exchanging bobbins in a sewing machine.

In sewing, a necessary maneuver which must be periodically performed is the replenishing of the bobbin thread supply. Thus, where relatively long sewing opersewing operations, a supply of rewound or new bobbin spools are kept on hand for ready replacement of the used bobbins as needed. In either case, bobbin changing procedures of the past have been cumbersome and time consuming. Accordingly, some attempts have been made in recent years to eliminate such timeconsuming manual operations, by automatically exchanging the bobbins in sewing machines.

The real importance of automatically exchanging bobbins of course lies in the mechanized field of sewing, such as in garment factories, where even short delays for removing and replacing bobbins considerably reduce the capacity of a machine and thereby become quite costly in the terms of overall production. Here, it is quite important to reduce the number oftimes a sewing machine operator must be concerned with changing a bobbin. Heretofore, the automatic exchange of bobbins in'sewing machines has been accomplished, for example, by providing a magazine adapted to be filled with a plurality of bobbin cases with full bobbins and transfer devices for lifting the empty bobbin cases from the bobbin holder of the sewing machine, discarding the empty bobbin case, picking up the next full bobbin case from the magazine and inserting this full bobbin case into the bobbin holder. Although such devices for effecting the automatic exhange of bobbins as previously provided have been operated with some degree of success and constitute an important advancement in the art, they nevertheless have not been found to be entirely satisfactory, primarily because they involve complex mechanical arrangements which accordingly are slow in completing the bobbin exchanges.

' SUMMARYOF THE INVENTION It is therefore an object of this invention to provide an improved automatic bobbin changer for sewing machines which is simple in construction and is quickly operative to replace used bobbins whereby to increase the capacity of the machine by reducing the idle time thereof.

Another object of the present invention is to provide an apparatus for automatically exchanging bobbins which is applicable to any conventional form of sewing machine having a bobbin holder. 7 1

Yet another object of the present invention is to provide a bobbin changer for sewing machines which simplifies the procedure by replacing a complete bobbin instead of a spool and is capable of automatically effecting a plurality of bobbin changes without manual assistance. A further object of this invention is to provide a bobbin changer for a sewing machine responsive to the completion of a predetermined number of pieces being sewn with the machine for automatically replacing the bobbin being used therein with a new bobbin.

The foregoing and other objects are attained with a bobbin changer constructed according to the present invention which essentially comprises a cylindrical bobbin container, a cycling mechanism,-a clutch-brake and a control system. The cylindrical bobbin container houses a plurality of bobbins in a circular array below the work plate of a sewing machine such that the uppermost bobbin in the array may be utilized by a standard sewing machine in a conventional manner and is connected to the cycling mechanism to be rotated thereby about its longitudinal axis for moving a new bobbin in the array into an operative position. The clutch-brake device is positioned between a drive motor of the cycling mechanism and the main drive of the sewing machine for declutching and braking the main drive while the bobbin cylinder is being cycled and for disengaging the brake and reengajging the clutch after the bobbin has been cycled to resume the sewing operation. During cycling, conventional control systems are employed to maintain a proper relationship between the stitching instrumentalities, such as between the loop-taker and the needle. One such system is found in U.S. Pat. No. 3,125,973, for example. A stitch counter and a piece counter are provided in the control system whereby after a predetermined number of pieces have been sewn with a predetermined number of stitches in each from a particular bobbin, the cycling mechanism is automatically acutated for rotating the cylindrical bobbin container to exchange the used bobbin with a new bobbin in the circular array and simultaneously the clutch-brake device is actuated for declutching and braking the sewing machine main drive to prevent operation of the machine while the bobbin exchange is being made.

BRIEF DESCRIPTION OF THE DRAWINGS machine, with an interior portion thereof being partially exposed, having the present invention applied thereto;

FIG. 2 is a top view of the automatic bobbin changer according to this invention, as seen in FIG. 1, withthe top plate of the sewing machine therein being removed;

FIG. 3 is a cross-sectional view taken along the line 3-3 of FIG. 2 showing the bobbin drive and clutch of the cycling mechanism;

FIG. 4 is a cross-sectional view taken along the line 4-4 of FIG.- 3 showing a solenoid-actuated spring- .biased index locking pin of the cycling mechanism;

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 2 showing the cycling mechanism being engaged for rotating the cylindrical bobbin container;

FIG. 6 is a cross-sectional view taken along the line 6-6 of FIG. 2;

FIG. 7 is a perspective view of the bobbin drive clutch mechanism;

FIG. 8 is a perspective view for illustrative purposes showing the cylindrical bobbin container and the bob bin drive clutch mechanism;

FIG. 9 is a schematic illustration of a control circuit for the automatic bobbin changer embodied within the present invention;

FIG. 10 is a diagrammatic illustration of the clutchbrake device of the present invention;

FIG. 1 1 is a schematic of an alternate electronic control circuit for the automatic bobbin changer of the present invention;

FIG. 12 is a side view of an alternate contruction of the cylindrical bobbin container and its connection with the sewing machine housing; and

FIG. 13 is an end view of the housing wall shown in FIG. 12 for receiving the cylindrical bobbin container also illustrated therein.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT Referring now to the drawings, and particularly to FIG. 1 thereof, the reference numeral 10 generally indicates the automatic bobbin changer of the present invention as it is applied to a sewing machine which is conventional in everything concerning the stitch forming. Thus, the sewing machine has the usual arm 11 provided with a presser foot 12 which can be let down upon a work plate 13 which supports the piece of materialas it is fed by means of any known step feeding device. A vertically reciprocating needle bar 14 also is carriedby the arm 1 l and is driven by a horizontal shaft 15 having a belt pulley 16 at the opposite end of the .machine. The. main horizontal shaft'l5 also is connected to a drive shaft 17 through a belt connection 18 for driving a bobbin with bottom thread disposed in a cylindrical bobbin container 20 below the work plate 13 and constructed in a known manner so that a loop of the top thread brought down through the material being sewn and a needle hole in the work plate 13 is turned over the bobbin thread, whereupon as the top thread is stressed upwardly, a stitch is formed in the usual manner.

The cylindrical bobbin container 20 is illustrated in greater detail in FIG. 8. As shown, the container has four pins 21 spaced at 90 intervals along a circular line therein for supporting a plurality of bobbins in a circular array. Although shown as being four in number and hereinafter described specifically to such an arrangement, it is to be understood of course that it is possible within the teachings of this invention to construct a device which accommodates a different number of bobbins.

Axially disposed within the cylindrical bobbin container 20 is a bearing sleeve 22 having an integral flange 23 positioned intermediate its ends and having a projecting end 24 which is adapted to receive a shaft 25 secured by suitable means to an end wall 26 of a housing 27 supported beneath the work plate 13 of the sewing machine. The shaft 25 has a threaded bore 28 which receives an elongate threaded bolt 29, as shown in FIG. 3, extending through a bearing member 30 positioned in the other end of the sleeve 22 so that the cylindrical bobbin container 20 may be freely rotated about its longitudinal axis relative to the housing 27 through the interconnecting sleeve '22 and shaft 25, as will be described hereinbelow.

Each of the bobbin-supporting pins 21 is rotatably disposed in a bearing sleeve 32 threadedly secured to the cylindrical container 20 and has a disc-like member 33 on which there is a drive element in the form of a tooth 34 fixed to the end thereof facing the adjacent wall 26 of the housing 27. A mating disc-like element 35 having a slot 36 formed therein, being substantially circular but for a small radial bar 37, for receiving the tooth 34,as shown also in FIGS. 7 and 8, is fixed to one end of a shaft 38 projecting from the end wall 26 of housing 27 and being axially movable therein, as'will be set forth further in this description, for engaging and disengaging the teeth 34 of the various members 33and the slot 36 of the member 35 such that these members constitute a clutch mechanism for the bobbin changer.

The cyclingmechanism of this invention will now be described with reference particularly to FIGS. 2, 4 and 5. Secured to one end face of the cylindrical bobbin container 20 is a gear 40 in meshing engagement with another gear 41 mounted on the end of a shaft 42 journailed in and projecting from the end wall 26 of housing 27 and with which, in the particular arrangement 1 herein disclosed, there exists a gear ratio of 4:1. Slidably mounted in a slot 39 at the other end of the shaft 42 is a keyed indexing clutch member for the bobbin container generally indicated by the numeral 43 and having atoothed gearing end surface 44, a cam 45 and an intermediate portion 46 of reduced diameter. Disposed between the cam body 45 and the housing end wall 26 is a compressed coil spring 47 for normally urging the slidable clutch member 43 away from the wall 26 and in the direction of another toothed end surface of a gear member 48 mounted on the endof a drive shaft 49 of a motor 50.

On a bracket 52 secured to the end wall 26 within the housing 27 is a solenoid 53 operable to retract a pin 54 which is normally urged by a coil spring 55 in a direction radially aligned with the reduced diameter portion 46 of the clutch member 43. A hole 56 is provided in the reduced diameterportion 46 of clutch member 43 adjacent the cam surface thereof and a stop adjacent thereto in the form of a longitudinal extension of the cam surface across the reduced diameter portion joining the gear end 44, so that rotation of the shaft 49 by the drive motor 50 upon retraction of the pin 54 from the hole 56 by the solenoid 53 is effective to turn the spur gear 41 through a single revolution whereby becaue of the 4:1 gear ratio the gear 40 is turned through to. place a new bobbin in position for use. Also, at the end of a revolution of the shaft 49, the cam surface 45 guides the pin 54 into the hole 56 and simultaneously the pin 54 operates to force the clutch member 43 to the left, as viewed in FIG. 5, against the biasing action of the spring 47, whereby the driving connection between the

gears

44 and 48 is disengaged. When the.

indexing pin 54 falls into position in the hole 56, the new bobbin is stopped in precisely the correct position.

Turning now to FIGS. 2, 3 and 4 in particular, the drive for the bobbin cylinder 20 will now be further described. I-Iereinbefore mentioned are the clutching members 33 for each of the bobbins and the common clutching member 35, the latter being mounted on an axially movable shaft 38. A ball-socket connection positioned intermediate the length of the shaft 38 joins the shaft 38 to one end of a rocking arm 57 which is pivotally connected at 58 to the wall 26 within the housing 27. A link 59 is pivotally connected at one end at 60 to an intermediate portion of the rocking arm 57 and at its other end at 61 to an arm 62 of solenoid 63. Thus, solenoid 63 is operative through link 59, rocking arm 57 and the ball-socket joint 51 to move the shaft 38' axially for engaging and disengaging the

clutch members

33 and 35 of the bobbin drive clutch mechanism.

Between the opposite end of the shaft 38 which is journalled in another wall of the housing 27 and the ball-joint 51, the shaft 38 carries a gear 64 which meshes with a gear 65 mounted on the end of the sewing machine drive shaft 17m whereby upon engagement of the

members

34 and 35 of the bobbin drive clutch mechanism, the uppermost bobbin within the bobbin cylindrical container 20 is driven by the main driving shaft of the sewing machine. 1

Briefly, in review, the automatic bobbin changer of the present invention comprises a cylindrical bobbin container housing four bobbins located in a circular array at 90 intervals, the top bobbin being utilized by a standard sewing machine in a conventional manner, that is being driver by the sewing machine drive shaft 17 through

gears

65 and 64, shaft 38,

clutch members

33 and 35, and the bobbin pin 21. When the top bobbin is expended, the cylindrical container 20 is rotated through 90 so that a second bobbin is in the top position. When this bobbin is expended, a third bobbin is rotated and so on, with means to replace the expended bobbins while the machine is still sewing. The replacement of bobbins may be done manually while the fourth bobbin is being-utilized.

In cycling the cylindrical bobbin container 20, solenoid 53 retracts pin 54 from hole 56 in the clutch index member 43 to permit the clutch member to be moved by spring 47 for engaging

gears

44 and 48. Thereafter, motor 50 drives shaft 49 and through the

gearing connection

44 and 48, shaft 42 is rotated for rotating gear 41 thereon through a single revolution. After approximately 80 turn of the cylindrical bobbincontainer 20, the pin 54 of the now de-energized solenoid 53 follows thecam surface 45 and is guided back into the hole 56. Ashereinbefore described, riding engagement of the cam surface 45 and the pin 54 is effective to move the clutch indexing member 43 to the-left, as viewed in FIG. 5, in the slot 39, whereupon the gears. 44 and 48 are disengaged and the new bobbin is stopped in precisely. the correct position. With reengagement of the bobbin drive

clutch mechanism

33, 34, 35 and 37 through operation of the solenoid 63, sewingwith the new bobbinmay be resumed.

A control system embodied within the present invention is illustrated in FIG. 9 and reference is now made thereto.

A stitch counter 70 of conventional design is provided for counting the stitches of each piece being sewn and is connected with another counter 71 for keeping count of the total number of pieces having been sewn from any particular bobbin. Thus, an input count may be provided from a microswitch pulser 72 which may be mounted with an eccentric gear being engaged and disengaged during each revolution of the sewing ma- A source of power, such as an alternating current supply, is shown being connected through a switch 73 and

lines

74 and 75 across a main driving motor 76 of the sewing machine to provide input power to the terminals 1 and 2 of the stich counter 70. Connected across

lines

74 and 75 and in parallel relation are a relay R1, time delay relays Agl and Ag2, and a brake wheel solenoid 77. The brake solenoid 77 is also connected serially through normally open contacts between the

terminals

12 and 13 of the stitch counter 70 and a normally open contact Agl to the power input terminals 1 and 2 of the piece counter 71. Also positioned in line 75 being connectedacross the

terminals

12 and 13 of stitch counter 70 are normally open contacts R1 and normally closed contacts Ag2.

In another line connected across

lines

74 and 75, normally closed contact Ag2", a relay R2 and normally open contacts R2 are connected, ,with a reset switch 78 being connected across the normally open contacts R2.

A main drive clutch-braking mechanism circuit is connected across line 75 and a branch line 79 of line 74 leading to the relays R1, Agl and Ag2, being powered through a 90 volt direct current power supply 80 having a variable resistor 81 connected thereacross for regulatingthe amount of voltage being applied to the clutch and brake, and'has a normally open contact Bl for the main drive brake 82 and normally closed contacts R1" for the clutch 83 being connected in parallel paths leading across the variable resistance.

A bobbin changer control circuit is illustrated as being powered from the alternating current power supply through line 84 and through

lines

74 and 79,

terminals

12 and 13 of the piece counter 71 andnormally open contacts therebetween, and a braking wheel switch 85. The circuit includes the cycling motor 50 and a switch 87 therefor, the bobbin drive solenoid 63 and a switch 88 associated therewith, and the single revolution clutch solenoid 53 being mechanically linked with the switches 87 and 88.

Accordingly, in operation, when the predetermined number of stitches in a piece is counted by the stitch counter 70, the following sequence takes place. First,

the contacts between

terminals

15 and 16 on the stitch counter momentarily close so that a pulse is sent to the input of the piece counter 71 between

terminals

3 and 4 thereof. Then the contact between

terminals

12 and 13 of stitch counter 70 momentarily close, thereby supplying power to the relay coils R1, Ag] and Ag2.

Normally closed contacts R then open through. energization of the relay R1, thus removing direct current power from the main drive clutch 83, and normally open contacts R1 are closed to apply power to the main drive brake 82. Simultaneously, the normally open contacts R1 in line close to latch the relay R1 in its energized state through normally contacts Ag2.

Time delay relays Agl and Ag2beginv their time delays which are preset so that relay Agl is operative first for closing the normally open contacts Agl to thereby apply power to the wheel brake solenoid 77'so that the sewing machine is latched in a needle-up position. When time delay relay Ag2 reaches its preset time, normally closed contacts Ag2 are opened, allowing relay R1 to be unlatched and removing power from relay R1 and time delay relays Agl and Ag2. All of the switching contacts associated with the relays are thus returned to their initial positions so that power is removed from the brake 82 and reapplied to the clutch 83, and sewing resumes.

When the stitch counter 70 again reaches its predetermined count, that is, when another piece has been sewn, the same sequence of events occurs. If, when the pulse sent to the piece counter causes the preset number of pieces sewable with a single bobbin to be reached, the following sequence of events occurs simultaneously with those already described.

First, the normally open contacts between

terminals

12 and 13 of the piece counter 71 close. When the wheel brake solenoid switch 85 is closed by operation of the wheel brake solenoid 77 as hereinbefore described, power may now be applied to the components in the automatic bobbin changer, namely the bobbin drive solenoid 63 and the single revolution clutch solenoid 53. Actuation of the bobbin drive solenoid 63 causes the drive shaft 38 of the extended bobbin to be disengaged while actuation of the single revolution clutch solenoid 53 operates to move the pin 54 out of the hole 56 in the clutch index member 43. Axial movement of the drive shaft 38 through the rocking arm 57 also is effective to activate the switch 87, as shown in FIG. 3, whereupon power is applied to the cycling drive motor 50 and is removed from the single revolution clutch solenoid 53. The cycling drive motor 50, through the aforedescribed gear system, rotates the bobbin cylinder through a quarter-tum and the single revolution clutch 43 disengages the motor 50 mechanically when the new bobbin is moved into position.

The reset switch 78 on the bobbin changer mechanism is actuated after the bobbin container 20 has turned through approximately 80 for latching relay R2 through the normally closed contacts Ag2' and upon energization thereof, the relay closes the normally open contacts R2 in the piece counter 71 thereby removing power from the bobbin drive solenoid 63, and also closes the normally open contacts R2 being connected in parallel with the reset switch 78. The drive shaft 38 thus is axially displaced causing the new bobbin to be engaged and the machine is ready to continue sewing whenever the time delay relay Ag2 times out, as hereinbefore described.

Referring now to FIG. 10, there is shown a schematic version of the clutch-braking device of the present invention for being positioned between a drive motor of the machine for declutching and braking the same while the bobbin cylinder is being recycled and for disengaging the brake and re-engaging the clutch after the bobbin has been cycled to resume sewing. Thus, drive motor 76 is shown being connected to the clutchbraking device through a coupling member 88 for driving the sewing machine through a belt 89, belt pulley 16 and drive shaft 15. A circular wheel member 90 is affixed to the belt pulley 16 having a slot 91 formed therein for receiving a locking arm 92 pivotally connected to the movable arm 93 of wheel locking solenoid 77. The precise operation of the clutch-braking device is believed to be fully covered in the description of the control circuit of FIG. 9.

An alternative electronic control for the automatic bobbin changer of the present invention is illustrated in FIG. 11 being composed of various electronic assemblies which are readily available on the commercial market. In this arrangement, a signal comes into the control system from a switch on the sewing machine which is made and broken during each revolution of the machine, or with each stitch sewn thereby. This signal passes through a filter for removing unwanted noise and transients from the pulses and through a Schmidt triggering device 101. Provided the clutch on the sewing machine is engaged, the pulses pass through an AND gate 102 to the stitch counter 70, and the count is displayed on a visible readout 163.

When the stitch counter reaches a predetermined number, which will be the number of stitches in a piece, a signal is sent through line 104 to the clutch-

brake assembly

83, 82 for disengaging the clutch and activating the brake. The disengagement of the clutch may be seen to be accomplished through the use of a NAND gate disposed between line 104 and the driver 106 of the clutch, so that the clutch 83 is always engaged except when a signal is transmitted by the stitch counter. A predetermined number of revolutions are made before the locking solenoid 77 is engaged, which occurs when signals are received both from the pulser 72 and from the stitch counter 70 in an AND gate 107 which responsively signals a stop counter 108 and the driver mechanism 109 of the solenoid 77. While the clutch is disengaged, pulses are inhibited from entering the stitch counter 70 because no signal is being transmitted from the NAND gate to the AND gate 102. After a predetermined delay, the stich counter is reset, the clutch is re-engaged, the brake is disengaged, and pulses are allowed to pass in the stich counter once again.

Each time the stitch counter 70 reaches its predetermined count, one pulse is sent to the piece counter 71, being registered on the readout display 110. When a predetermined count is reached by the piece counter, which is the number of pieces that can be sewn from a single bobbin, a signal is emitted from the piece counter to an AND gate 11 1. When the signal from the piece counter and a signal from the stop counter 108 which stops the sewing machine, are both present at the AND gate 111, a signal is produced that is delayed at 112 and then applied to drive motor 50 of the bobbin cycler 20 for removing the expended bobbin and replacing it with a new bobbin.

When the new bobbin is in place, the piece counter 71 is reset to O.

To inhibit the stitch counter from being reset prematurely and thereby allowing the sewing machine clutch to engage while the bobbin is cycling, the output of the piece counter is also applied through the AND gage 111 to a NAND gate 113, in turn being connected along with a delay 114 from line 104 to an and gate 115, thereby inhibiting the resetting of the stitch counter until the piece counter is reset.

Referring now to FIGS. 12 and 13, an alternate method of securing the cylindrical bobbin container 20 to the wall 26 of housing 27 is illustrated, featuring a quick bayonet-type locking device. As shown, diametrically opposed arcuate locking slots having enlarged bores 120' at one end thereof are provided in the end wall 26, along with a central hole 121 disposed therein at the center of the circle defined by the arcuate slots 120. Affixed to the end surface of tye cylindrical bobbin container 20 and disposed thereon intermediate the bobbin driving elements 33 is an elongate shaft 25 having a flanged surface 122 on the end thereof, to which are secured" pin members 123 of a diameter such as to slidably fit within the slots 120 and having enlarged heads 124 thereon being of substantially the same diameter as the holes 120 for being received therein, whereupon with a turning moment the cylindrical bobbin container 20 may be secured to the wall 26 with the pin heads 124 being locked through the slots 120 on the opposite end of the wall 26. In all other manners, the cylindrical bobbin container 20 may be the same as it is illustrated in FIG. 3. With this embodiment, however, it is possible to quickly replace a bobbin container having all bobbins therein being expended of thread with a new bobbin container having a fresh supply of bobbins. Obviously, this may provide an even quicker maneuver than replacing the various expended bobbins in the bobbin container while it is maintained in position on the wall 26 of housing 27.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings, It is to be understood, therefore, that within the scope of the appended claims the invention may be practiced otherwise than as specifically described herein.

What is claimed as new and desired to be secured by letters patent of the United States is:

1. An automatic bobbin changer for a sewing machine comprising:

a cylindrical bobbin container for housing a plurality of bobbins in a substantially circular array being rotatably supported about its longitudinal axis in said sewing machine and having a plurality of first clutch members corresponding in number to the number of bobbins that may be housed therein;

driving means for' engaging the one of said plurality of bobbins in a selected angular position on said circular array and driving the same, having a second clutch member adaptedto selectively engage said first clutch members; i

a cycling mechanism for rotating said cylindrical bobbin container; and

- control means for disengaging said dirving means and for actuating said cycling mech anism for moving a new bobbin into said selected angular position to align it with said driving means and for reengaging said driving means, including a rotatable shaft for supporting said second clutch member, means for axially moving said rotatable shaft in a reciprocable path, and means for rotating said clutch membersupporting shaft.

2. An automatic bobbin changer as set forth in claim 1, wherein said control means further comprises means responsive-to said axial movement in one direction of said second clutch member-supporting shaft for actuating said cycling mechanism.

7 3. An automatic bobbin changer for a sewing machine comprising:

driving means for engaging the one of said plurality of bobbins in a selected angular position on said circular array and driving the same having a second clutch member adapted'to selectively engage said first clutch members;

a cycling mechanism for rotating said cylindrical bobbin container. incuding a first gear'mounted on said cylindrical bobbin container, a second gear meshingly engaging said first gear being rotatably supported on a shaft, a drive motor for turning said second gear-supporting shaft, and an indexing clutch means between said drive motor and said second gear-supporting shaft; and

control means for disengaging said driving means and for actuating said cycling mechanism for moving a new bobbin into said selected angular position to align it with said driving means and for reengaging said drivng means. i

4. An automatic bobbin changer as set forth in claim 3, wherein said indexing clutch means comprises:

a third gear member on a shaft of said drive motor;

an axially movable fourth gear member mounted on said second gear-supporting shaft;

means for normally urging said axially movable fourth gear member toward said third gear member on said drive motor shaft;

means engageable with said movable fourth gear member for resisting said urging means and maintaining said fourth gear member and said third gear member separate; and

means for disengaging said engaging means to permit said axially movable gear member to be moved by said urging means into engagement with said third gear member.

5. An automatic bobbin changer as set forth in claim 4, wherein said axially movable fourth gear member is provided with an aperture, said means engageable therewith is a pin member adapted to fit within said aperture, said means for disengaging said pin from said aperture is a solenoid, and said indexing clutch further comrises a cam profile member on said axially movable gear member engageable with said pin member upon withdrawal thereof from said aperture for permitting said drive motor to turn said second gear member through a single revolution, whereupon said pin member becomes reengaged with said aperture.

6. An automatic bobbin changer as set forth in claim 1, wherein said control means further comprises:

stitch counting means operably connected to said sewing machine for counting the number of stitches being sewn from one of said plurality of bobbins; and electrical circuit means responsive to the counting of a predetermined number of stitches by said stitch counting means for disengaging said driving means and actuating said cycling mechanism. 7. An automatic bobbin changer as set forth in claim 1, wherein said control means further comprises:

stitch counting means operably connected to said sewing machine for counting the stitches being sewn thereby; piece counting means for counting the number of individual pieces being sewn by said sewing machine; means responsive to the counting of a predetermined LII LII

number of stitches in said stitch counting mens for successively stopping the operation of said sewing machine, latching the sewing machine in a needleup position, registering a count in said piece counting means and resuming said sewing operation; and means responsive to the counting of a predetermined number of pieces in said piece counting means for stopping the operation of said sewing machine, latching the sewing machine in a needle-up position, disengaging said driving means and actuating said cycling mechanism, resetting the count registered therewithin and resuming the sewing operation.

8. An automatic bobbin changer for a sewing machine comprising:

a cylindrical bobbin container for housing a plurality of bobbins in a substantially circular array being rotatably supported about its longitudinal axis in said sewing machine;

driving means for engaging the one of said plurality of bobbins in a selected angular position on said circular array and driving the same;

a cycling mechanism for rotating said cylindrical bobbin container;

a clutch and braking means for the main drive of the sewing machine;

means operably. connected to said sewing machine for counting the number of stitches being sewn thereby;

piece counting means for counting the number of individual pieces being sewn by said sewing machine;

means responsive to the counting of a predetermined number of stitches in said stitch counting means for successively actuating said clutch and braking means to register and brake the main drive of the sewing machine, regiwter a count in said piece counting means and resume sewing by disengaging the brake and re-engaging the clutch of said clutch and braking means; and

means responsive to the counting of a predetermined number of pieces in said piece counting means for actuating said clutch and braking means to declutch and brake the main drive of the sewing machine, disengage said driving means of said one of said plurality of bobbins, actuate said cycling mechanism for moving a new bobbin into said selected angular position to align it with said driving 4

Claims

1. An automatic bobbin changer for a sewing machine comprising: a cylindrical bobbin container for housing a plurality of bobbins in a substantially circular array being rotatably supported about its longitudinal axis in said sewing machine and having a plurality of first clutch members corresponding in number to the number of bobbins that may be housed therein; driving means for engaging the one of said plurality of bobbins in a selected angular position on said circular array and driving the same, having a second clutch member adapted to selectively engage said first clutch members; a cycling mechanism for rotating said cylindrical bobbin container; and control means for disengaging said driving means and for actuating said cycling mechanism for moving a new bobbin into said selected angular position to align it with said driving means and for reengaging said driving means, including a rotatable shaft for supporting said second clutch member, means for axially moving said rotatable shaft in a reciprocable path, and means for rotating said clutch member-supporting shaft.

2. An automatic bobbin changer as set forth in claim 1, wherein said control means further comprises means responsive to said axial movement in one direction of said second clutch member-supporting shaft for actuating said cycling mechanism.

3. An automatic bobbin changer for a sewing machine comprising: a cylindrical bobbin container for housing a plurality of bobbins in a substantially circular array being rotatably supported about its longitudinal axis in said sewing machine and having a plurality of first clutch members corresponding in number to the number of bobbins that may be housed therein; driving means for engaging the one of said plurality of bobbins in a selected angular position on said circular array and driving the same, having a second clutch member adapted to selectively engage said first clutch members; a cycling mechanism for rotating said cylindrical bobbin container including a first gear mounted on said cylindrical bobbin container, a second gear meshingly engaging said first gear being rotatably supported on a shaft, a drive motor for turnIng said second gear-supporting shaft, and an indexing clutch means between said drive motor and said second gear-supporting shaft; and control means for disengaging said driving means and for actuating said cycling mechanism for moving a new bobbin into said selected angular position to align it with said driving means and for reengaging said driving means.

4. An automatic bobbin changer as set forth in claim 3, wherein said indexing clutch means comprises: a third gear member on a shaft of said drive motor; an axially movable fourth gear member mounted on said second gear-supporting shaft; means for normally urging said axially movable fourth gear member toward said third gear member on said drive motor shaft; means engageable with said movable fourth gear member for resisting said urging means and maintaining said fourth gear member and said third gear member separate; and means for disengaging said engaging means to permit said axially movable gear member to be moved by said urging means into engagement with said third gear member.

5. An automatic bobbin changer as set forth in claim 4, wherein said axially movable fourth gear member is provided with an aperture, said means engageable therewith is a pin member adapted to fit within said aperture, said means for disengaging said pin from said aperture is a solenoid, and said indexing clutch further comprises a cam profile member on said axially movable gear member engageable with said pin member upon withdrawal thereof from said aperture for permitting said drive motor to turn said second gear member through a single revolution, whereupon said pin member becomes reengaged with said aperture.

6. An automatic bobbin changer as set forth in claim 1, wherein said control means further comprises: stitch counting means operably connected to said sewing machine for counting the number of stitches being sewn from one of said plurality of bobbins; and electrical circuit means responsive to the counting of a predetermined number of stitches by said stitch counting means for disengaging said driving means and actuating said cycling mechanism.

7. An automatic bobbin changer as set forth in claim 1, wherein said control means further comprises: stitch counting means operably connected to said sewing machine for counting the stitches being sewn thereby; piece counting means for counting the number of individual pieces being sewn by said sewing machine; means responsive to the counting of a predetermined number of stitches in said stitch counting means for successively stopping the operation of said sewing machine, latching the sewing machine in a needle-up position, registering a count in said piece counting means and resuming said sewing operation; and means responsive to the counting of a predetermined number of pieces in said piece counting means for stopping the operation of said sewing machine, latching the sewing machine in a needle-up position, disengaging said driving means and actuating said cycling mechanism, resetting the count registered therewithin and resuming the sewing operation.

8. An automatic bobbin changer for a sewing machine comprising: a cylindrical bobbin container for housing a plurality of bobbins in a substantially circular array being rotatably supported about its longitudinal axis in said sewing machine; driving means for engaging the one of said plurality of bobbins in a selected angular position on said circular array and driving the same; a cycling mechanism for rotating said cylindrical bobbin container; a clutch and braking means for the main drive of the sewing machine; means operably connected to said sewing machine for counting the number of stitches being sewn thereby; piece counting means for counting the number of individual pieces being sewn by said sewing machine; means responsive to the counting of a predetermined number of stitches in said stitch counting means for successively actuating said clutch and braking means to declutch and brake the main drive of the sewing machine, register a count in said piece counting means and resume sewing by disengaging the brake and re-engaging the clutch of said clutch and braking means; and means responsive to the counting of a predetermined number of pieces in said piece counting means for actuating said clutch and braking means to declutch and brake the main drive of the sewing machine, disengage said driving means of said one of said plurality of bobbins, actuate said cycling mechanism for moving a new bobbin into said selected angular position to align it with said driving means, re-engage said driving means, reset the count in said piece counting means and reactuate said clutch and braking means of said main drive for disengaging the brake and reengaging the clutch thereof.

9. An automatic bobbin changer as set forth in claim 8, wherein said cylindrical bobbin container comprises means cooperable with said sewing machine for quickly disconnecting and connecting the bobbin container and the sewing machine.

10. An automatic bobbin changer as set forth in claim 9, wherein said quick disconnecting and connecting means comprises a bayonet-type locking engagement.