Brother Kogyo Kabushiki-kaisha

Toshio Sasaki

Masao Ogawa

Hiroaki Fukao

Osamu Kamiya

Nobusuke Nagasaka

Teruhiko Ohkita

Yukio Ichihara

Minoru Itoh

This invention provides an overlock sewing machine with a threading mechanism that is both easier and more efficient to use. As shown in FIGS. 1 and 7, the overlock sewing machine has a vertically movable needle (6, 106), a looper carriage (18, 118) connected to a rotating shaft, and a looper (11, 111) on the end of the looper carriage. The looper extends laterally over the looper carriage and has a thread-receiving eye (11a, 111a). The looper and the needle cooperate to form a chain stitch. As shown in FIGS. 3 and 9, a thread-guiding member (25, 125) next to the looper pivots with the looper to guide a thread LT through the thread-receiving eye. A movable lever (30, 130) pivots with or relative to the looper. A thread-delivering member (39, 139) mounted on the movable lever that can be set in two positions: a first position corresponding to a first position of the thread-receiving eye, and a second position corresponding to the thread-guiding member. In the second position, the thread passes through the thread-guiding member.

Overlock sewing machine with a threading mechanism for easily threading

In a sewing machine provided with a thread supply stopping device for selectively controlling supply of a needle thread between a needle thread supply source and a take-up lever, an adjustable pre-tension exerting device exerts a tension equal to or lower than a tension of a bobbin thread on the needle thread between the needle thread supply source and the thread stopping device.

Needle thread tension control including separate stopping and adjustable

In a conventional sewing machine, as the take-up lever is driven by the take-up lever crank, the take-up lever does not keep its uppermost position during the feed motion of a work fabric. Accordingly, the length of the thread path extending from the thread supply source to the eye of the needle varies remarkably during feed motion, and thus the needle thread equivalent to the amount consumed by stitch feed motion cannot be extracted from the supply source. In the present automatic needle thread supply control system, during a specific period from a time before finishing of each feed motion to a time when the needle reaches the throat plate, the take-up lever is held at its uppermost position. During a given period corresponding to the comparatively latter half of the specified period, thread supply stopping is released, whereby the needle thread equivalent to the amount consumed by each stitch feed motion can be extracted certainly from the supply source toward the take-up lever. The present thread supply control system comprises, at least, thread securing means or driving means, thread supply stopping means and mechanical control means.

Automatic needle thread supply control system

There is disclosed a needle threader comprizing a support provided with a needle accommodating notch and a thread guide groove, and a pair of resilient rollers rotatably mounted on the support and contacting at the respective peripheral edges with each other. In the needle threader, an eye of a needle accommodated in the needle accommodating notch is located on a tangent line passing through the contact portion of the pair of resilient rollers. A thread introduced via the thread guide groove towards the proximity of the contact portion of the pair of resilient rollers is gripped by and transferred through rotation of the resilient rollers, resulting in the thread being passed through the eye of the needle.

Needle threaders for a sewing machine

Disclosed is a zigzag sewing machine in which a trimming device for trimming the marginal edge of a work fabric is removably disposed at a predetermined position on a machine bed so that the trimming device is driven in relation to the operation of the sewing machine. The zigzag sewing machine comprises a switching device for changing the field position of the needle oscillation and an operated member for actuating the switching device in relation to the disposition of the trimming device at the predetermined position. In this zigzag sewing machine, while overedge stitching is performed by using the trimming device, the field position of the needle oscillation is set so that zigzag stitches having a desired stitch width are always placed along and over the marginal edge of the work fabric trimmed by the trimming device.

Zigzag sewing machine with a trimming device

A zigzag sewing machine wherein, when a pattern selecting means is manually operated for selecting a desired stitch pattern, at least one of an amplitude regulator and a feed regulator is automatically set, in accordance with the manual operation of said selecting means, to a certain suitable condition which is previously designed to form a master stitch pattern for each pattern to be selected, and wherein at least one of manually operable knobs which are operatively connected with the two regulators, respectively, is not only automatically set at the same time with the regulator setting, indicating the set condition thereof, but also adjustable to change the set condition within a certain range for forming a modified stitch pattern similar to the master pattern.

Growing community of inventors

Inazawa, Japan

Toshio Sasaki