Abstract: In an automated bobbin-exchanger device (3), a guide groove (6) which is provided on a vertical transfer base (5) has a horizontal portion (6a), a vertical portion (6c) and an arcuate portion (6b). A bobbin chuck (18) reciprocally moves pivotably along the guide groove (6) to make a travel distance minimum, thus enabling users to quickly exchange the bobbin case (12). By placing a bobbin holder (13a), a chuck-drive lever (14) and a chuck-drive air-cylinder (26) circumferentially, it is possible to make a whole structure compact and space-saving. The bobbin-exchanger device (3) requires only two bobbin cases (12) available to make their check and maintenance easy.

Abstract: A hook (15) of a sewing machine (1) is pivotably mounted on a hook carrier (25). The hook (15) is moved from a working position (X) into a bobbin case withdrawal position by a pivoting movement of the hook carrier (25). The pivoting movement displaces the hook (15) and the bobbin case (17) towards or above the opening which is opened by the flap (13) in the lower arm (13). In this way, the withdrawal of the bobbin case (17) or the bobbin is significantly simplified.

Abstract: An arrangement for changing bobbins in sewing and embroidery machines is arranged on the cover (13) on the lower arm of the sewing machine (1). With a push-button (45) and a slide (19), the bobbin case (71) with the bobbin (73) lying therein is released from the hook base (75) and made accessible to outside of the sewing machine (1) when the cover (13) is opened.

Abstract: A lower thread winding device is structured such that it comprises: lower thread supply means for guiding a lower thread out from a lower thread supply source and also for supplying the lower thread to a bobbin through an opening formed in a bobbin case; bobbin rotate means including a rotary body disposed on a bobbin within the bobbin case in such a manner as to be contactable with and separatable from the bobbin, the bobbin rotate means being capable of rotating the bobbin due to mutual contact between the rotary body and bobbin to thereby wind the lower thread around the bobbin; and, a thread handling member, after completion of winding of the lower thread around the bobbin, for handling a lower thread extended from the bobbin case to the lower thread supply source to thereby guide the lower thread from the opening of the bobbin case up to a slit formed in the peripheral side surface of the bobbin case.

Abstract: In a remote control bobbin case exchanger device (1), a rotary bobbin (K) is to be placed in a position that is not easily accessed, and an exchangeable position (&agr;) is provided in a position that is readily accessed in a bobbin case providing member (3). A chuck driving member (6) moves a chuck member (5) toward the rotary bobbin (K) to clutch a bobbin case (2) along a line connecting the rotary bobbin (K) to the exchangeable position (&agr;).

Abstract: The apparatus allows to automatically change bobbin cases in quilting machines. The apparatus comprises a pick-up element which is mounted on a carriage which can move between a magazine which contains full cases and a hook assembly of a sewing machine in which an empty case is to be replaced. The pick-up element extracts the empty case and deposits it into a specifically provided container. It is further positioned at the magazine, from which it removes a full case and transfers the case into the hook assembly.

Abstract: A residual thread removing device detects an amount of thread left in a bobbin of a sewing machine. The bobbin exchange time setting means sets a time to exchange a bobbin set in the sewing machine with a new one to a bobbin exchange time at which an amount of thread providing a minimum of unusable thread is left in the bobbin, on the basis of the detected thread amount. With such an arrangement, a bobbin exchange time can be set to an optimal time at which a waste of the thread in a bobbin is minimized, irrespective of a kind of thread and/or thread count.

Abstract: An automatic bobbin exchanger, to be incorporated into a sewing machine, automatically replaces a bobbin case having a bobbin with a small amount of remaining lower thread, with a bobbin case having a fully wound lower-thread bobbin. The automatic bobbin exchanger includes a pair of two dummy shafts and a rotary arm having a grip mechanism for releasably holding a bobbin case. The dummy shafts are provided at positions opposable to a moving path of the rotary arm. One of the dummy shaft holds a fully wound bobbin and the other holds a bobbin with a small amount of the remaining lower thread. Preferably, a remaining-thread mover unit which completely removes the small amount of remaining lower thread around the bobbin and a lower-thread winder which winds lower thread around the empty bobbin may be provided at positions opposable to a moving path of the rotary arm.

Abstract: An under thread supply apparatus for a sewing machine comprises a bobbin case, a bobbin exchange device, a thread removal device and a winding device. The bobbin case is removably set to a shuttle of the sewing machine and accommodates a bobbin with the thread wound thereon. The bobbin exchange device takes the bobbin case out of the shuttle, and set the bobbin case accommodating the bobbin with the thread wound anew therearound to the shuttle. The thread removal device removes the thread from the bobbin accommodated in the bobbin case which is taken out. The winding device winds a preset amount of thread around the bobbin after the thread is removed therefrom.

Abstract: An under thread supply apparatus for a sewing machine comprises a bobbin case, a bobbin exchange device, a thread removal device and a winding device. The bobbin case is removably set to a shuttle of the sewing machine and accommodates a bobbin with the thread wound thereon. The bobbin exchange device takes the bobbin case out of the shuttle, and sets the bobbin case accommodating the bobbin with the thread wound anew therearound to the shuttle. The thread removal device removes the thread from the bobbin accommodated in the bobbin case which is taken out. The winding device winds a preset amount of thread around the bobbin after the thread is removed therefrom.

Abstract: An under thread supply apparatus for a sewing machine comprises a bobbin case, a bobbin exchange device, a thread removal device and a winding device. The bobbin case is removably set to a shuttle of the sewing machine and accommodates a bobbin with the thread wound thereon. The bobbin exchange device takes the bobbin case out of the shuttle, and sets the bobbin case accommodating the bobbin with the thread wound anew therearound to the shuttle. The thread removal device removes the thread from the bobbin accommodated in the bobbin case which is taken out. The winding device winds a preset amount of thread around the bobbin after the thread is removed therefrom.

Abstract: An automatic bobbin-winding machine, in particular for lockstitch machines, comprises a changing head (27) with pneumatically driven gripping levers (30,31) for removing the lower part (35) of the bobbin case holder from the sewing machine. The changing head (27) can pivot or oscillate about various axes (39,40,41) and move on a carriage (26). It cooperates with a magazine (22) arranged alongside the axis (39). A second changing head (27') which can pick up empty and full bobbins (2) alternately may also be arranged on the carriage (26).

Abstract: Sewing apparatus comprises a sewing needle, a bobbin for feeding thread to the sewing needle, a rotary housing containing the bobbin and its case a sensor for sensing the non-feeding of thread to the sewing needle; an extraction-reloading device automatically effective, upon sensing the non-feeding of the thread to the sewing needle, for first extracting the bobbin and its case from the rotary housing, then extracting the bobbin from its case, then reloading the case with another bobbin having a supply of thread thereon and then returning the case with its reloaded bobbin into the rotary housing.

Abstract: A bobbin run-out detector for a lockstitch sewing machine is responsive to thread tension for sensing when the bobbin is empty of thread. The thread tension is sensed by a hook member (168; 332) engageable with the thread extending from the bobbin, the hook member (168; 332) being moved by a resilient bias as a result of loss of thread tension consequent on emptying of the bobbin. The hook member (168; 332) is linked to a shutter (174; 334) which moves with the hook member (168; 332) in order to influence a light beam, light receiving means (202) being responsive to such influence to produce a signal indicative of bobbin run-out. The signal may stop the machine and/or actuate an alarm. Alternatively, the signal may actuate a bobbin change device (2, 4, 14, 16) for removing the empty bobbin and for inserting a previously wound bobbin, to permit sewing to resume.

Abstract: An apparatus for changing bobbins and bobbin carriers in a sewing machine utilizes a magazine having an opening, containing a bobbin carrier, aligned between the bobbin housing and an electromagnet which pushes the bobbin carrier through the opening into the bobbin housing and then withdraws. The magazine withdraws; the electromagnet moves adjacent the bobbin housing, and in withdrawing pulls a spent bobbin carrier therefrom and drops it. The magazine moves into alignment again between the bobbin housing and the electromagnet, and the cycle repeats. A computer, responsive to apparatus positions, regulates pneumatic valves and an electrical source to automatically effect operations.

Abstract: An apparatus is disclosed for automatically substituting a fully threaded bobbin assembly for a used bobbin assembly in a thread shuttle of a sewing machine having the bobbin assembly latched to the thread shuttle. A pivoted hook unlatches the spent bobbin assembly from the thread shuttle and then a plunger extracts the spent bobbin assembly and places it in a magazine. The magazine carries a new and full thread bobbin assembly and the plunger transfers the full thread bobbin assembly into latched engagement with the thread shuttle. An electric control system including an automatic counter counts the number of sewing operations and after a predetermined number of sewing operations causes the automatic exchange of bobbin assemblies.

Abstract: The disclosure is directed to automatic bobbin rewinding for sewing machines. A two-station mechanism is provided enabling bobbins to be transferred from a winding position to a sewing position, with one bobbin being at all times in each position. When a bobbin is exhausted, that bobbin and its case are removed from the sewing machine and, simultaneously, a filled bobbin is removed from the winding position and combined with its case. The bobbin positions are then reversed, enabling the filled bobbin and its case to be inserted in the sewing machine, while the just-removed bobbin is separated from its case and inserted in the winding position. The filled bobbin remains attached to the main thread supply until it is inserted in the sewing position, enabling the thread to be guided and controlled until picked up by the sewing mechanism, thus avoiding the need for manual intervention.

Abstract: The present invention is an automatic bobbin changer for sewing machines of the lock stitch type having bobbin holders with holder pins and latches. A magazine of full bobbins and cases is positioned adjacent the sewing machine, and a cross slide is provided which is movable from a first position to a second. This slide is provided with two powerful magnets, preferably permanent magnets, which are spaced on the slide so that in one position one magnet is aligned with the sewing machine bobbin holder and the second is aligned with the full bobbin magazine. The two magnets are provided with actuators, preferably fluid operated actuators, which can move the magnets forward so that they contact, respectively, an empty casing in the sewing machine bobbin holder and a full bobbin and casing in the magazine. The two magnets then retract toward the slide and the slide moves to the second position.