Sewing machine

Abstract

A sewing machine includes a thread take-up, a thread take-up driving mechanism driving the thread take-up, a thread cutting mechanism including a fixed cutting blade and a movable cutting blade both cutting the needle thread and a movable cutting blade driving mechanism driving the movable cutting blade, a thread wiper wiping the cut needle thread away over workpiece cloth, a wiper driving mechanism driving the thread wiper, and a control device which, upon receipt of a needle thread cutting command to actuate the thread cutting mechanism, controls the movable cutting blade driving mechanism and the wiper driving mechanism so that the thread wiper carries out a thread amount securing operation to secure a predetermined amount of needle thread located downstream relative to a needle eye of a sewing needle in a state previous to cutting of the needle thread where the needle thread is seized by the movable cutting blade.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present disclosure will become clear upon reviewing the following description of the embodiment with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a whole multi-needle embroidery machine of one embodiment in accordance with the present disclosure;

FIG. 2 is a front view of a needle bar case;

FIG. 3 is a partial longitudinally sectional left side view of the needle bar case;

FIG. 4 is a partial enlarged side view of the needle bar case as shown in FIG. 3;

FIG. 5 is a partial front view of the interior of the needle bar case;

FIG. 6 is a partial plan view of the interior of the needle bar case;

FIG. 7 is a plan view of a thread cutting mechanism;

FIG. 8 is a block diagram showing a control system of the multi-needle embroidery machine;

FIGS. 9A and 9B are flowcharts showing the thread cutting control; and

FIG. 10 is a view similar to FIG. 3, showing the case where a thread amount securing operation has been carried out by a wiper.

Claims

1. A sewing machine comprising: a needle bar having a lower end to which a sewing needle is attached;a thread take-up;a thread take-up driving mechanism which drives the thread take-up;a thread cutting mechanism including a fixed cutting blade and a movable cutting blade both of which cut the needle thread and a movable cutting blade driving mechanism which drives the movable cutting blade;a thread wiper which wipes the cut needle thread away over workpiece cloth to be sewn;a wiper driving mechanism which drives the thread wiper; anda control device which, upon receipt of a needle thread cutting command to actuate the thread cutting mechanism, controls the movable cutting blade driving mechanism and the wiper driving mechanism so that the thread wiper carries out a thread amount securing operation to secure a predetermined amount of needle thread located downstream relative to a needle eye of the sewing needle in a state previous to cutting of the needle thread where the needle thread is seized by the movable cutting blade.

2. The sewing machine according to claim 1, wherein the control device controls the thread take-up driving mechanism so that when the thread wiper carries out the thread amount securing operation to secure the predetermined amount of needle thread, the thread take-up is lowered a predetermined distance so that the predetermined amount of needle thread is secured by the thread wiper.

3. The sewing machine according to claim 1, further comprising a thread tension adjuster which adjusts a tension of the needle thread and a thread tension adjuster driving mechanism which drives the thread tension adjuster, wherein when the thread wiper is operated to secure the predetermined amount of thread, the control device controls the thread tension adjuster driving mechanism so that the thread tension adjuster is opened so that the predetermined amount of needle thread is secured by the thread wiper.

4. The sewing machine according to claim 2, further comprising a thread tension adjuster which adjusts a tension of the needle thread and a thread tension adjuster driving mechanism which drives the thread tension adjuster, wherein when the thread wiper is operated to secure the predetermined amount of thread, the control device controls the thread tension adjuster driving mechanism so that the thread tension adjuster is opened so that the predetermined amount of needle thread is secured by the thread wiper.

5. The sewing machine according to claim 1, further comprising a needle bar releasing mechanism which intermits a driving force of a needle bar driving mechanism which drives the needle bar, wherein when the thread wiper is operated to secure the predetermined amount of thread, the control device controls the needle bar releasing mechanism so that drive of the needle bar is interrupted by the needle bar releasing mechanism.