Abstract: A sewing machine can detect a sewing target feeding length, and includes: a presser rod, a presser main body detachably mounted on the presser rod, a movable presser portion mounted on the presser main body such that it can be pressed in contact with a sewing target in the sewing operation, and such that it is movable with the sewing target in feeding and reverse feeding directions; a movement transmission portion configured having one end that can be coupled with the movable presser portion, and having an other end that receives a position change of the one end; a slide volume that detects the position change of the other end, and a calculation unit that calculates the position change of the movable presser portion based on the detection result obtained by the slide volume.

Abstract: A sewing machine with an adjusting structure capable of controlling a swing center of a swing arm includes an adjusting apparatus and corresponding structures cooperating with the adjusting apparatus. The adjusting apparatus is provided on the pivotal portion with a sliding groove and a sliding block that can horizontally slide with respect to each other. Between the sliding groove and the sliding block are further provided an adjusting bolt and an elastic element. By rotating the adjusting bolt, the relative position between the swinging center around which the whole swing arm pivots and the whole structure of the swing arm can be changed in the horizontal direction accurately and conveniently, thus assuredly adjusting the start point of the travel of the presser foot, achieving the objective of accursedly adjusting position of the travel sensing apparatus.

Abstract: A sewing machine is provided. The sewing machine includes a needle, a feed dog which feeds a workpiece in a feeding direction, a stitching motor which vertically moves the needle, a needle swinging motor which swings the needle in a direction orthogonal to the feeding direction, a memory in which basic coordinate data of basic buttonhole stitches having a basic stitching width is stored, an input device from which a stitching width is input, and a control device which creates a modified coordinate data based on the basic coordinate data and the stitching width input from the input device, and controls the stitching motor and the needle swinging motor based on the modified coordinate data to form buttonhole stitches having the stitching width input from the input device.

Abstract: A sewing machine includes a needle bar to which a needle is attached, a needle bar rocking mechanism which rocks the needle bar, a needle plate having a needle hole through which the needle is passed, an imaging device which images a lower part of the needle bar, a setting section which sets a range of rocking motion of the needle bar based on an image obtained by the imaging device, and a control device which controls the needle bar rocking mechanism based on the range of rocking motion set by the setting section.

Abstract: Bight stitches at sides and bar tack stitches at ends of a buttonhole site are formed by periodically oscillating a needle bar holder over lesser and greater angles while a needle is in an up position. The needle bar holder is fixed to a horizontal transverse shaft. One end of a long, generally vertical arm is clamped to the shaft, and a generally horizontal link is pivoted to a lower end of the arm and to an adjustment slide in an upper arm of the inverted Y-shaped follower plate. The Y-shaped follower plate is pivoted on a central horizontal pivot. A double cam engages cam follower rollers oppositely extending from lower ends of the Y-shaped follower plate. Periodically, while the needle is up, the cams move the follower plate back and forth.

Abstract: A buttonhole sewing machine including stitching instrumentalities for forming zigzag stitches defining an eyelet-end buttonhole having an eyelet end portion at one end of a foot portion, by operations of a driving mechanism for operating a needle and looper device of the stitching instrumentalities, a feeding mechanism for feeding work fabric feeding table along X and Y axes, and a rotating mechanism for rotating a needle bar and looper base about an axis perpendicular to the X and Y axes, according to stitching data, and wherein the stitching data are compensated by a control device according to a designated one of compensation data sets stored in a compensation data memory.

Abstract: In a sewing machine having a feed adjusting device which is operated by means of a drive pulse motor, a feed adjusting member is pivoted relative to an attaching member such that the feed adjusting member is turned about an axis of an output shaft of the pulse motor by rotating a fine feed-adjusting member, an eccentric part of which is mounted in a groove formed in the feed adjusting member so that a fine adjustment of the feed pitch may be provided.

Abstract: A presser foot used in combination with a zigzag sewing machine, which is especially adapted to produce a combination stitch comprising a first half series of stitches and a second half series of stitches formed in the normal feeding direction. The presser foot is provided on the bottom at one side thereof with a recess in the feeding direction for preventing the precedingly formed first half series of stitches from contacting the bottom of the presser foot while the second half series of stitches are being formed.

Abstract: A process for stitching a buttonhole in the forward and reverse fabric feeding directions by means of a zigzag sewing machine including the step of producing one or more of stitches at a critical pattern changing point which will serve as a reference mark for enabling the sewing machine operator to operate the sewing machine as required with ease for the pattern changing operation.