Janome Sewing Machine Company Limited

Tamotsu Nakagawa

Hideaki Takenoya

Kazuo Watanabe

Susumu Hanyu

Hachiro Makabe

Yoshikazu Ebata

Yoshinobu Tonomura

Toshiaki Kume

Koshiro Omiya

Kenzi Kato

Hiroshi Inaba

Kouzi Okutani

A threading device of sewing machine is disclosed, wherein the upper thread extended from a thread supply mounted on a sewing machine body may be easily and smoothly guided into engagement with a thread holder simultaneously when the threading device is operated to pass the upper thread through the eye of needle attached to the lower end of needle bar, the thread holder being arranged between the thread supply and the needle. The threading device comprises a vertically movable needle barhaving a needle attached to the lower end thereof, the needle having a needle eye, a needle bar supportfor supporting the needle barsuch that the same may be vertically movable, a thread holdermounted to the lower end of the needle bar, a threading member Ahaving a thread engaging portionand a threading hook, a threading shaftfor having the threading member Asecured to the lower end thereof, an operating section C for vertically moving and axially rotating the threading shaftto pass the upper thread n through the needle eye, the threading member Abeing so formed as to provide the thread engaging portionfor guiding the upper thread to the needle eye, the needle holderbeing formed with a groovefor holding the upper thread n, the groovehaving an openingat which the upper thread n is guided into the groovefrom the rear side of the thread holderwhile the thread engaging portionis moved down with the upper thread n which is to be passed through the needle eye

Threading device of sewing machine

A devised shank is provided to a presser foot of a sewing machine in addition to an ordinary shank, such that a special presser group for straight stitching along a fabric edge is attached to the devised shank only, in which the presser foot is attachable to a presser holder, and the ordinary shank is for such as zigzag stitching, and the devised shank is different in an attaching width from the ordinary shank. Signal generating parts are provided to the presser holder, which each issue a signal in response to when the presser foot is attached, and the signal is discriminated with a signal issued in response to a pattern group belonging to patterns selected by a pattern selecting means so that the sewing machine is driven only when the presser group and the pattern group is met.

Fabric presser device of a sewing machine

The invention is to provide an electrical indication of improper thread tension to enable the sewing operation to be exactly accomplished.

Thread tension control signal output device for sewing machine

The tension of the sewing machine's upper thread is varied automatically, in a variety of ways not requiring conscious participation on the part of the user of the machine. When one of a set of selectable stitch-patterns is selected by the user, an appropriate thread-tension value is automatically established, although the user retains the ability to adjust the automatically established tension value if he wishes. When the user swings the presser-foot lever of the machine up, to raise the cloth presser foot up from the cloth, e.g., for basting work, the thread tension is automatically lowered to a predetermined value suitable for basting, although still adjustable by the user if he thinks necessary. Where a stitch-pattern is implemented using an addressable ROM, tension command data for each stitch of the stitch-pattern may be stored in the ROM, for variation of thread tension from constituent stitch of the pattern to the next. Alternatively, the ROM stores no tension control data per se, and instead a calculating circuit calculates, from the mere stitch-control data presented by the ROM, distance-dependent values dependent upon the distances between successive needle-penetration locations of the stitch-pattern, and from those derives appropriate tension command signals.

Sewing machine with thread-tension control system

A rows-and-columns array of indicator lamps, each lamp associated with a selectable stitch pattern, is provided on the machine housing, with one pushbutton switch per column of indicator lamps. In a first embodiment, when a particular column and row contain the single illuminated one of the lamps, depression of the pushbutton switch associated with a different column terminates illumination of the presently lighted lamp and instead effects illumination of the lamp of the same row but in the column associated with the newly depressed pushbutton switch, whereupon repeated pressing of the newly pressed switch causes the illuminated state to shift, lamp by lamp, along such column. Alternatively, when the illuminated-lamp indication is located in a particular row and column, depression of the pushbutton switch associated with a different column causes the illuminated-lamp indication to jump to that column, and in particular always to a predetermined lamp within that column, e.g., the first therein. In this way, when the number of selectable stitch patterns is large, a comparatively small number of pushbutton switches can be utilized to control pattern selection in a way involving a regular and predetermined rule of displacement of the illuminated-lamp indication from column to column.

Growing community of inventors

Hachioji, Japan

Tamotsu Nakagawa