Apparatuses, methods, and computer program products for quilting webs without compressing the webs. A quilting machine includes a needle bar to which needles are attached, needle thread passing through each needle, a looper shaft to which loopers are attached, a looper corresponding to each needle and from which looper thread is provided to form stitches, and a retainer bar to which spreaders are attached to facilitate stitching. A drive pulley powered by a first servo motor rotates cranks to move the needles through a cycle and rotates a belt which rotates an indexer pulley. Rotation of the indexer pulley oscillates the looper shaft and reciprocates the retainer bar. Another drive pulley powered by a second servo motor operates to move an input web through the machine between chain stitches.

Apparatuses, methods, and computer program products for quilting webs without compressing the webs. A quilting machine includes a needle bar to which needles are attached, needle thread passing through each needle, a looper shaft to which loopers are attached, a looper corresponding to each needle and from which looper thread is provided to form stitches, and a retainer bar to which spreaders are attached to facilitate stitching. A drive pulley powered by a first servo motor rotates cranks to move the needles through a cycle and rotates a belt which rotates an indexer pulley. Rotation of the indexer pulley oscillates the looper shaft and reciprocates the retainer bar. Another drive pulley powered by a second servo motor operates to move an input web through the machine between chain stitches.

With a overlock sewing machine, when a switching mechanism is switched to a threading-enabled state, and a looper cover is closed, the looper cover is slid toward one side in the hinge shaft axial direction so as to operate a detection lever. In the non-operating state, the detection lever is set to an initial position where it does not press an operation protrusion of a switch. When a side cover is closed, and the detection lever is operated, the operation lever is set to an operation-enabled position where it presses the operation protrusion. When the operation lever is operated, and the side cover is opened, the detection lever is set by passing through the operation-enabled to the operation-disabled position where it does not press the operation protrusion.

Hook (11, 12, 13, 14) for a lockstitch sewing machine, or parts of the hook such as the support element of the tension spring (in particular the basket or the bobbin case) or the tension spring itself, including a tension spring (80, 90, 100, 110, 120) that includes a bending towards the outside (with respect to the support element on which it is mounted and with respect to the main bending radius of the tension spring) of the tension spring's extremity designed to press on the bobbin thread, so that the pressure point (P) on the bobbin thread is the point of tangency between the bending radius (R) of the bending of the tension spring's extremity and the support element of the tension spring, so as to generate a stable tension of the bobbin thread.

Hook (11, 12, 13, 14) for a lockstitch sewing machine, or parts of the hook such as the support element of the tension spring (in particular the basket or the bobbin case) or the tension spring itself, including a tension spring (80, 90, 100, 110, 120) that includes a bending towards the outside (with respect to the support element on which it is mounted and with respect to the main bending radius of the tension spring) of the tension spring's extremity designed to press on the bobbin thread, so that the pressure point (P) on the bobbin thread is the point of tangency between the bending radius (R) of the bending of the tension spring's extremity and the support element of the tension spring, so as to generate a stable tension of the bobbin thread.

Apparatuses, methods, and computer program products for quilting webs. A quilting machine includes a cutting edge, a looper from which thread is provided to form stitches, and an adjuster assembly that includes a plurality of selectable positions. The adjuster assembly extends an adjuster toward the thread between the looper and the retainer. When the adjuster is moved, a predetermined amount of thread is pulled away from the looper by the adjuster to provide a controlled length of thread between the looper and the cutting edge. The adjuster is configured to be moved to an intermediate selectable position prior to starting a quilting pattern, and from the intermediate position to another selectable position subsequent to starting the quilting pattern.

Apparatuses, methods, and computer program products for quilting webs. A quilting machine includes a cutting edge, a looper from which thread is provided to form stitches, and an adjuster assembly that includes a plurality of selectable positions. The adjuster assembly extends an adjuster toward the thread between the looper and the retainer. When the adjuster is moved, a predetermined amount of thread is pulled away from the looper by the adjuster to provide a controlled length of thread between the looper and the cutting edge. The adjuster is configured to be moved to an intermediate selectable position prior to starting a quilting pattern, and from the intermediate position to another selectable position subsequent to starting the quilting pattern.

The length of a sewing machine stitch is adjustable by varying the effective length of a first bar of a multi-bar linkage operably secured to a feed dog of the sewing machine. The effective length of the first bar is defined between an anchor point and a pivot point, with the pivot point being secured to a slider configured for movement along the length of the first bar. The slider comprises a pinion gear configured to engage a gear rack of the first bar, such that rotation of the pinion gear causes movement of the slider and the pivot point relative to the anchor point. Moreover, to accommodate the adjustable stitch length, the sewing machine additionally comprises an adjustable looper thread eyelet configured to adjust the length of the looper thread path to accommodate increased tension or slack in the looper thread due to the changed stitch length.

The length of a sewing machine stitch is adjustable by varying the effective length of a first bar of a multi-bar linkage operably secured to a feed dog of the sewing machine. The effective length of the first bar is defined between an anchor point and a pivot point, with the pivot point being secured to a slider configured for movement along the length of the first bar. The slider comprises a pinion gear configured to engage a gear rack of the first bar, such that rotation of the pinion gear causes movement of the slider and the pivot point relative to the anchor point. Moreover, to accommodate the adjustable stitch length, the sewing machine additionally comprises an adjustable looper thread eyelet configured to adjust the length of the looper thread path to accommodate increased tension or slack in the looper thread due to the changed stitch length.

The present invention provides a sewing machine that can actuary detect a physical amount of a movement of a fabric without depending on an estimated value. Thus, thread tension can be precisely adjusted. A sewing machine 1 includes a spherical body 22a exposed partly from a needle plate 2. The spherical body 22a is rotated following a feed of a fabric 100. The rotation of the spherical body 22a is detected by rotary encoders 22c, 22d. A physical amount of the movement of the fabric 100 is calculated based on a detection result of the rotary encoders 22c, 22d. The physical amount of the movement of the fabric 100 is, for example, a moving amount and a moving speed.