Brother Kogyo Kabushiki-Kaisha

Hajime Suzuki

Kazuhisa Ito

In a sewing machine, when the depressed condition of a foot pedal is changed from a forward depressed condition for high speed sewing to a reverse depressed condition for thread cutting, a braking circuit decreases the rotational speed of the machine motor from a high speed to a low speed. The rotational speed is detected by an encoder. When the rotational speed detected by the encoder becomes a threshold medium speed or less, and a needle-down signal is generated from a needle position detector, the CPU of the sewing machine outputs a work fabric feed pitch control start signal to a work fabric feed pitch selector. The work fabric feed pitch selector reduces or nullifies the feed pitch of the work fabric. Under this condition, in response to the next needle-down signal, the CPU operates a thread cutting mechanism to cut the needle and bobbin threads.

Sewing machine with automatic thread cutter

A thread holding device having a thread holding member and a holding force imparting member selectively engageable therewith for holding a leading end portion of a needle thread. The thread holding member and the holding force imparting member are pivotally movable by drive means through linking means. The thread holding member has a first angular rotational position at a position below a sewing needle for trapping the leading end portion of the needle thread, a second angular rotational position at a position beside the sewing needle for holding the thread in cooperating with the holding force imparting member, and a third angular rotational position or a retracted position. When the thread holding member is moved from its second to third angular positions, the needle thread leading end is released from the thread holding member.

Needle thread holding device for holding leading end portion of the

A sewing machine having a needle thread cutting unit and a needle thread holding device for holding a cut leading end portiion of the thread drawn from an eye of a needle. The needle thread holding device includes a holding means provided at the pressure foot. The holding means is movable between a needle thread clamping position and a needle thread releasing position. The holding device also includes drive means connected to the holding means for selectively moving the holding means to one of the needle thread releasing position and the needle thread clamping position, pressure foot position detection means for detecting a position of the pressure foot, needle position detector for generating a needle position signal indicative of the upper needle position and the lower needle position, and control means connected to the pressure foot position detection means the sewing machine energization signal generating means and the needle position detector. The controlling means maintains the holding means at its thread clamping position when the pressure foot is at its non-operative position after cutting the needle thread. The controlling means also maintains the holding means at its clamp position during a predetermined number of stitches at a starting phase of a next sewing operation.

Needle thread holding device in sewing machine

A sewing machine provided with a thread cutting mechanism and a needle thread tension release mechanism. Normally, the needle thread is subjected to a proper tension by a thread tension regulating mechanism. However, at an initial start-up period of the sewing operation, the needle thread tension is released by the tension release mechanism for a first predetermined period during which a needle thread loop is trapped by a loop taker. Further, the sewing machine is provided with a thread holding member for holding a leading end portion of the needle thread. The holding member is movable to its thread release position after elapse of a second predetermined period at the initial start-up period of the sewing operation. The first predetermined period is within the second predetermined period.

Growing community of inventors

Nagoya, Japan

Hajime Suzuki