JPS6228296Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a crease removal device for a sewing machine, which is equipped with a crease removal blade that performs crease removal in cooperation with a differential feed dog.

In this type of creasing device, an arm is attached to the shaft that supports the creasing blade, and a coil spring acts on the arm to urge the blade downward and press it against the throat plate to follow the vertical movement of the feed dog. The type shown in Utility Model Publication No. 54-35804, and the type shown in U.S. Pat. No. 3,608,507, in which a torsion coil spring is wound around the shaft supporting the creasing blade to urge the blade downward. The latter type has the advantage of being more compact than the former type, and is less likely to get in the way of work, but on the other hand, the strength of the spring can be adjusted depending on the sewing conditions. If adjustment is necessary, one end of the torsion coil spring is locked, the collar fixed to the shaft is rotated by a jig, etc. by loosening the set screw, and then tightening the set screw again. Because of this, it is very time consuming and extremely difficult for unskilled people to make fine adjustments.

This invention aims to eliminate the above-mentioned drawbacks of the latter type.

The figure shows an embodiment of the present invention.
Bracket 2 fixed to
A fork-shaped adjustment stand 4 is pivotably mounted so as to be rotatable in the horizontal direction. The blade shaft 5 mounted on the forked portion of the adjustment table 4 is rotatable (the axial movement is achieved by holding one of the forked portions between a stepped portion formed on itself and a lever described later). In use, the main feed dog 7 is attached to its protruding end (blocked).
and the differential feed dog 8 (or the main feed dog side in the case where the main feed dog and the differential feed dog are arranged oppositely) are pressed by the action of a torsion coil spring, which will be described later. The removing blade 9 is attached. The blade shaft 5 also has a worm wheel 11 and a lever 12 connected between the two prongs of the adjustment table 4 with a torsion coil spring 13 interposed therebetween, so that the worm wheel 11 can rotate around the blade shaft 5. The lever 12 is fixedly provided. The torsion coil spring 13 acts to rotate the worm wheel 11 and the lever extractor 12 in opposite directions, but since the worm wheel 11 is engaged with the worm 15 that is attached to the adjustment base 4, Although it is possible to rotate the worm wheel 11 by turning the worm wheel, the worm wheel cannot rotate the worm, so it will not rotate due to the action of the spring. On the other hand, the lever 12 is biased in one direction by the action of the spring, and presses the crease removing blade 9 against the needle plate 17 on the differential feed dog side as described above. The blade 9 pressed against the throat plate moves up and down following the up and down movement of the differential feed dog 8, causing the blade shaft to swing. Although the blade 9 pressed against the throat plate can have a function as a stopper against the rotation of the blade shaft due to the action of the spring, it is preferable that the boss part of the lever 12 has the function as a stopper as shown in FIG. It is desirable to form an engaging portion 18 to hold the rotor, and to stop the rotation by engaging the adjusting base 4 with the engaging portion 18. This allows the blade to move in the direction shown by the two-dot chain line in Fig. 2 when not in use, so that it will not rotate more than necessary even if it is removed from the throat plate 17, and the load due to the action of the spring will not be applied to the blade when in use. It won't get any hotter than necessary. The adjustment table 4 also has a protruding positioning pin 19 that determines the working position of the blade, so that it hits the bracket when the adjustment table rotates from the non-working position of the blade and reaches the working position. A leaf spring 2 that passes through the adjustment table vertically and always engages the lower end.
The spherical head of the pin 22, which is biased upward by the pin 1 and projected from the adjustment table, fits into the recess 23 of the bracket 2 (FIG. 3) to hold the blade in the operating position. I have to.

When inserting the cloth under the presser foot 24 and the blade prior to the start of sewing work, it is necessary to lift both of them above the throat plate. For this reason, in this device, the blade 9 is rotated and lifted in conjunction with the lifting of the presser foot. That is, the other side of the bell crank 26, whose intermediate portion is pivotally supported on the bracket 2 and whose one end is connected to the presser foot lifting mechanism, engages from below with a pin 27 that protrudes laterally from the lever 12, thereby raising the presser foot. 24 is lifted, the bell crank 26 rotates clockwise in FIG. I have to.

This device is constructed as described above, and when not in use, it is retracted to the position shown by the two-dot chain line in FIG. After being set, the cloth held between the differential feed dog 8 and the blade 9 is subjected to pleat removal by differential feed.

If it is necessary to adjust the strength of the torsion coil spring depending on the number of rotations of the sewing machine or the type of fabric, this can be done by rotating the worm wheel using a screwdriver or jig. This twists or untwists the spring. When rotating the worm, the worm can be rotated more easily if a knob for rotating the worm is removably attached or fixed to the worm.

The fold removal device of the present invention is configured as described above,
It is relatively compact and does not easily interfere with work, and the strength of the torsion coil spring can be easily and finely adjusted by rotating the worm.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a sewing machine equipped with a pleating device according to the present invention, Fig. 2 is a plan view of the same device, Fig. 3 is a sectional view taken along line A-A in Fig. B- in the diagram
It is a sectional view taken along the B line. 2... Bracket, 4... Adjustment stand, 5... Blade shaft, 9... Crease removing blade, 11... Worm wheel, 12... Lever, 13... Torsion coil spring, 15... Worm, 24... ...Fabric presser foot.

Claims (1)

[Claims for Utility Model Registration] (1) An adjustment table 4 that is rotatable in the horizontal direction about a fixed axis, a blade shaft 5 rotatably supported horizontally on the adjustment table, and an adjustment table 4 A worm wheel 11 is rotatably attached to the blade shaft and meshes with the worm 15, and a worm wheel 11 is wound around the blade shaft and has one end connected to the worm wheel. A torsion coil spring 13 that is locked and whose other end is connected to the blade shaft to urge the blade shaft in one rotation direction, and a main feed dog 7 that is fixed to the blade shaft and aligned in the feed direction during use, and a differential A crease removal device for a sewing machine comprising a crease removal blade 9 pressed against the front feed dog side of the feed dog 8 by the action of the spring 13. (2) The pleat removal device for a sewing machine according to claim 1, wherein a knob is attached to the worm 15. (3) The pleating device for a sewing machine according to claim 1, wherein the other end of the spring is fixed to the blade shaft and is locked to a lever 12 that is interlocked with a presser foot lifting mechanism. (4) The pleat removing device for a sewing machine according to claim 3, wherein the lever is provided with a stopper 18 for restricting rotation due to the action of the spring.