Cloth-holder frame transfer apparatus for sewing machine

Abstract

A cloth-holder frame transfer apparatus for a sewing machine includes a carriage detachably attachable to a cloth-holder frame holding workpiece cloth, a carriage driving mechanism including an actuator moving the carriage in two directions intersecting each other on a horizontal plane, an external force detector which detects an external force applied to the cloth-holder frame attached to the carriage, an assisting force output device which produces force assisting the movement of the cloth-holder frame by the external force, and a control device which controls the assisting force output device based on the external force detected by the external force detector.

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 illustrative examples with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a multineedle sewing machine in accordance with one illustrative example of the disclosure;

FIG. 2 is a plan view of a cloth-holder frame and a carriage driving mechanism;

FIG. 3 is a block diagram showing an electrical arrangement of the control system of the multineedle sewing machine;

FIG. 4 is a flowchart showing a successive control executed by a control device;

FIG. 5 is a flowchart showing a control manner of a normal pattern sewing;

FIG. 6 is a flowchart showing a control manner of a feed control;

FIG. 7 is a flowchart showing a first half of control manner of the normal pattern sewing in a second embodiment of the present disclosure;

FIG. 8 is a flowchart showing a second half of control manner of the normal pattern sewing, namely, a process of obtaining an amount of movement of external force in a second illustrative example;

FIG. 9 is a flowchart showing a feed control;

FIG. 10 is a flowchart showing a control manner of process of obtaining an amount of movement of external force in a third illustrative example;

FIG. 11 is a flowchart showing a control manner of process of obtaining the amount of movement of external force;

FIG. 12 shows a normal pattern to be formed on workpiece cloth;

FIG. 13 is a flowchart showing a control manner of process of obtaining an amount of movement of external force in a fourth illustrative example;

FIG. 14 shows pattern data;

FIG. 15 shows a normal pattern to be formed on workpiece cloth;

FIG. 16 shows a normal pattern to be formed on workpiece cloth;

FIG. 17 is a flowchart showing a control manner of normal pattern sewing in a fifth illustrative example;

FIG. 18 is a flowchart of external force processing;

FIG. 19 is a flowchart of sewing speed control; and

FIG. 20 is a flowchart of feed control.

Claims

1. A cloth-holder frame transfer apparatus for a sewing machine which is usable with a cloth-holder frame, the apparatus comprising: a carriage detachably attachable to the cloth-holder frame holding workpiece cloth;a carriage driving mechanism including an actuator moving the carriage in two directions intersecting each other on a horizontal plane;an external force detector which detects an external force applied to the cloth-holder frame attached to the carriage;an assisting force output device which produces force assisting the movement of the cloth-holder frame by the external force; anda control device which controls the assisting force output device based on the external force detected by the external force detector.

2. The apparatus according to claim 1, wherein the control device actuates the assisting force output device when the external force detected by the external force detector has a magnitude equal to or larger than a predetermined threshold.

3. The apparatus according to claim 2, wherein the control device controls the assisting force output device so that the assisting force is produced in a direction of the external force detected by the external force detector.

4. The apparatus according to claim 1, wherein the carriage driving mechanism includes first and second direction movement actuators which are provided with first and second direction displacement sensors respectively.

5. The apparatus according to claim 4, wherein the assisting force output device shares the first and second direction movement actuators with the carriage driving mechanism.

6. The apparatus according to claim 4, wherein the first and second direction movement actuators comprise respective stepping motors, and the first and second direction displacement sensors comprise respective rotary encoders.

7. The apparatus according to claim 1, wherein the assisting force output device comprise the carriage driving mechanism, and the control device controls the carriage driving mechanism so that the cloth-holder frame is moved in the direction the external force detected by the external force detector.

8. The apparatus according to claim 1, wherein the sewing machine includes a needlebar to which a sewing needle is attachable, the apparatus further comprising a needlebar position detector which detects a vertical position of the needlebar to which the sewing needle is attached, wherein the control device controls the assisting force output device so that the assisting force output device is actuated only when the sewing needle assumes a needle-up position where the sewing needle is located higher than the workpiece cloth.

9. The apparatus according to claim 8, wherein the control device controls the assisting force output device based on the external force detected by the external force detector when the sewing needle assumes a needle-down position where the sewing needle is stuck into the workpiece cloth.

10. The apparatus according to claim 7, wherein the control device controls the carriage driving mechanism so that an amount of movement of the cloth-holder frame is varied according to a magnitude of the external force detected by the external force detector.

11. The apparatus according to claim 7, wherein the control device controls the carriage driving mechanism so that an amount of movement of the cloth-holder frame is constant irrespective of a magnitude of the external force detected by the external force detector.

12. The apparatus according to claim 1, wherein the sewing machine includes a sewing needle, a needlebar to which the sewing needle is attachable and a sewing machine motor driven to move up and down the needlebar attached with the sewing needle, and the control device controls the sowing machine motor according to a magnitude of the external force detected by the external force detector.

13. The apparatus according to claim 11, wherein the sewing machine includes a sewing needle, a needlebar to which the sewing needle is attachable and a sewing machine motor driven to move up and down the needlebar attached with the sewing needle, and the control device controls the sewing machine motor according to a magnitude of the external force detected by the external force detector.

14. The apparatus according to claim 1, wherein the control device controls the assisting force output device so that an assisting force for forming a predetermined stitch is produced in a direction of the external force detected by the external force detector.

15. The apparatus according to claim 11, wherein the control device controls the assisting force output device so that an assisting force for forming a predetermined stitch is produced in a direction of the external force detected by the external force detector.