JPS5920214Y2 - Overlock sewing machine overlock width switching device - Google Patents

Description

[Detailed description of the invention] This invention relates to an overlocking width switching device for an overlock sewing machine, and in particular, a thread sliding piece for setting the overlocking width is installed in parallel with a thread supporting piece provided integrally with the throat plate. The yarn sliding piece is configured to be movable back and forth between an active position provided in parallel with the thread sliding piece and a non-active position provided on the back side of the throat plate and shifted from that position in a direction intersecting the cloth feeding direction. A convex portion is formed on either the formed advancing and retracting rod or an elastic member that presses and supports the advancing and retracting rod, and a concave portion that engages with the convex portion when the thread slide piece is set at the operating position. By forming a structure in which the advancing/retracting rod and the elastic member can be hooked and held at the action position of the thread slider, the thread can be used for normal hem stitching due to the overlocking width between the thread support piece and the thread slider. Setting the slider to the working position and switching operation to set the thread slider to the non-working position for so-called rolled-in overlocking, in which the overlocking width of only the thread support piece is used to roll up the edge of the fabric while overlocking. This is simple and reliable, and furthermore, the scraps on the edges of the fabric made by the scalpel are not sewn into the overseams and can be easily disposed of.

Generally, when performing overlock stitches using an overlock sewing machine, it is desired that one sewing machine be able to perform overlock stitches with different overlock widths due to factors such as the thickness, material, and intended use of the fabric.

Conventionally, when changing the stitching width, (a) a needle plate having a thread support piece adapted to the specified stitching width is manufactured individually, and the specified throat plate is replaced and installed each time the stitching width is changed. or (b) arrange thread slip pieces in parallel to the thread support piece formed on the throat plate, and set the thickness and overlock width using the thread support piece and the thread slip piece. Overlocking work was performed by moving the thread sliding piece and adjusting the overlock width so that a narrow overlock width could be set using only the thread support piece.

However, in the case of the former (a), it is uneconomical because a new throat plate must be manufactured each time the stitching width is changed, and when using the throat plate, the needle plate must be manufactured every time the stitching width is changed. There was a problem that the work was not smooth due to the hassle of replacing the parts.

In the case of the latter (b), due to the structure in which the yarn slip piece is movably attached to the lower knife holder, the scraps from the edges of the cloth are not dropped by the knife, but are supported by the yarn slide piece located below. There were problems such as the chips getting caught on parts and the like, and the chips being sewn into the overseam again.

The inventor came up with this idea in view of this problem.

In other words, the purpose of this invention is to provide an overlock that makes it easy to switch the overlocking width setting using the thread support piece and the thread slider, and that allows the thread slider to be latched and held at the overlocking position, making sewing work safer. The purpose of this invention is to provide a sewing machine overlocking width switching device, and the purpose of this invention is to make it possible to move the thread sliding piece back and forth to an inactive position where it does not affect the fall of scraps from the edge of the fabric by a knife, so that The purpose of this invention is to provide an overlocking width switching device that can easily dispose of the overlocking width without sewing the overlocking scraps into the overlocking stitches.Furthermore, the purpose of this invention is to provide a device for switching the overlocking width that can easily dispose of the overlocking scraps without sewing them into the overseam. To provide an overlock width switching device for an overlock sewing machine that can be easily installed on a sewing machine.

Therefore, this invention, for example, as in the illustrated embodiment,
A thread support piece 2 that is formed integrally with the throat plate 1 and sets the narrow stitching width, and a needle plate 1 that sets the thick stitch width with the thread support piece 2 that is arranged in parallel with the thread support piece 2. The thread supporting piece 2 is moved by the cooperative action of a sewing needle 4 which has a thread sliding piece 3 separate from the sewing needle 3 and which moves up and down, and a looper 5 which swings in synchronization with the sewing needle 4.
or a width in which the thread support piece 2 and the thread sliding piece 3 are lined up to form overlock stitches with different overlock widths.
In the overlock sewing machine, the thread sliding piece 3 is formed at the tip of an advancing/retracting rod 7 having a knob 6 at the base in the longitudinal direction, and the advancing/retracting rod 7 is attached to a guide member 9 fixed to a sewing machine frame 8 by an elastic member. 10 to press and support the yarn slipping piece 3 at an action position N where it is provided in parallel with the thread support piece 2, and at the back side of the throat plate 1 shifted from the action position N in a direction intersecting the cloth feeding direction S. The movable lever 7 is configured to be able to move forward and backward between the inactive position M and the inactive position M.
Alternatively, one of the elastic members 10 has a convex portion 11 formed on one side, and a concave portion 12 opposite to the convex portion 11 is formed on the other member, and the reciprocating rod 7 and the elastic member are formed at the action position N of the thread sliding piece 3. The present invention relates to an overlock width switching device for an overlock sewing machine, characterized in that the overlock width switching device is configured such that the overlock sewing machine 10 can be hooked and held.

Below, according to the attached drawings of Figures 1 to 5,
An example of this invention will be described.

As shown in the figure, this invention relates to an overlock sewing machine, and this overlock sewing machine has a throat plate 1.
A thread support piece 2 for setting a narrow stitching width is integrally formed with the needle plate 1, and the thread support piece 2 is formed separately from the needle plate 1.
The sewing machine has a thread sliding piece 3 arranged in parallel with the sewing machine to set the thickness and stitching width, a sewing needle 4 that moves up and down, and a looper 5 that swings in synchronization with the sewing needle 4.

Furthermore, this overlock sewing machine has a narrow overlocking width due to only the thread support piece 2 or a thread support piece 2 and thread slipper piece 3 that are parallel to each other due to the cooperative action of the sewing needle 4 and the looper 5. It is equipped with a mechanism that allows the formation of different hem stitches, such as overlocking widths of specified thickness and width.

The thread support piece 2 is provided on the needle drop side of the throat plate 1 and extends in the cloth feeding direction S.

A thread sliding piece 3 oriented in the same direction as this thread supporting piece 2 is arranged in parallel.

The thread slip piece 3 has minute slopes formed on its outer and lower surfaces toward the tip thereof to facilitate the pulling out of the darning thread.

In such an overlock sewing machine, the rear end of the thread sliding piece 3 is connected to the tip of an advancing/retracting rod 7 having a knob 6 which is bent outward in the longitudinal direction and protrudes.

That is, in this embodiment, the thread sliding piece 3, the advancing/retracting rod 7, and the knob 6 are integrally formed according to the described order.

The advancing/retracting rod 7 is in the shape of an elongated flat plate, and is pressed and supported by a guide member 9 fixed to the sewing machine frame 8 by a leaf spring or other elastic member 10.

That is, a guide groove 13 having approximately the same width as the reciprocating rod 7 is formed on the upper end surface of the guide member 9, and the retracting rod 7 is fitted into this guide groove 13. It is pressed and supported by an elastic member 10 fixed with a bolt 14.

Further, the support of the advancing and retracting rod 7 by the guide member 9 and the elastic member 10 is carried out at an operating position N where the thread sliding piece 3 is arranged in parallel with the thread supporting piece 2 to set the stitching width, and from that position intersecting the cloth feeding direction S. The sewing machine is configured to be able to move forward and backward between a non-working position M, which is provided on the back side of the throat plate 1 and does not affect the overlocking stitches.

Furthermore, a convex surface 11 is formed on the surface of the elastic member 10 that presses the advancing/retracting rod 7, and when the thread sliding piece 3 is set to advance or retreat on the advancing/retracting rod 7 to the working position N and the non-acting position M,
Recesses 12 that engage with the projections 11 are formed at positions facing the projections 11, respectively.

In this way, when the advancing/retracting rod 7 is advanced or retracted to set the thread sliding piece 3 to the same position N or M of action or non-action, the recesses 12 formed on the advancing/retracting rod 7 and the convex portions 11 formed on the elastic member 10 are aligned. The elastic member 10 engages with the elastic member 10 so that the retractable rod 7 is retained.

In addition, in the figure, 15 is an upper knife for cutting the edge of the cloth, and 16 is a lower knife.

Further, 17 is a looper shaft, 18 is a looper base rod with a looper 5 provided at the tip, 19 is a swinging arm that connects the looper shaft 17 and the looper base rod 18, and 20 is a swinging arm. arm 19
This is a swinging link for imparting an overedge motion to the tip of the looper 5 by swinging.

In this embodiment, the head of the fixed shaft 21, which serves as the swinging fulcrum of the swinging link 20, is used as a guide member; Of course, it is possible.

Therefore, the overlocking width can be changed by grasping the knob 6 and moving the advancing/retracting rod 7 forward and backward together with the knob 6.
This can be done simply by switching the thread sliding piece 3 between the working position N and the non-working position M.

Furthermore, during this switching, the advancing/retracting rod 7 and the elastic member 10 are
Since it is held and held by the convex portions 11 and the four portions formed respectively, the thread slip piece 3 does not move forward or backward due to vibrations of the sewing machine itself.

As shown in the figure, this invention is preferably applied to an overlock sewing machine with a single looper;
Of course, this looper can also be applied to overlock sewing machines.

As described above, according to this invention, the width of the thread slide can be easily changed by grasping the knob and moving the advancing/retracting rod forward and backward together with the knob to switch the thread sliding piece between the working position and the non-working position. Since the advancing and retracting rods can be latched and held at the working position, the thread slip will not come off from the predetermined position even if the sewing machine itself vibrates, and the safety of the sewing work can be ensured.

In addition, the thread sliding piece can be moved back and forth between an inactive position, which is provided on the lower important surface side of the throat plate by shifting it in a direction that intersects with the cloth feeding direction, and an active position, which is installed in parallel with the thread supporting piece. Since no parts are exposed below the upper knife and lower knife for cutting the edges of the fabric, a large area for the chips to fall can be ensured.

Therefore, as is often the case with conventional devices of this kind, scraps from the edge of the fabric are not sewn into the overseam again, resulting in a beautiful seam, and the scraps can be easily disposed of.

Furthermore, the structure in which the thread slider is moved in a direction intersecting the cloth feeding direction and moved back and forth to a non-working position provided on the back side of the throat plate is particularly useful for overlock sewing machines with a single looper. Furthermore, since there is no obstacle to the installation and operation of the advancing and retracting rod formed with thread sliding pieces, even a beginner can perform the operation of switching the stitching width extremely easily.

Furthermore, the structure is simple and can be manufactured at low cost,
This is an overlock width cutting device for overlock sewing machines that can be easily installed on conventional sewing machines and is economical and highly practical.

[Brief explanation of drawings]

The drawings show one embodiment of this invention; Fig. 1 is a front view, Fig. 2 is a right side view, Fig. 3 is a plan view, and Fig. 4 is a cross section taken along line 4-4 of Fig. 1. Figures 5 and 5 are views showing a part of the throat plate. Figure A shows a state in which the stitch width is formed only by the thread support piece, and Figure B shows the stitch width formed by the thread support piece and the thread slip piece. It is a figure which shows the state which formed. In the figure, 1 is a throat plate, 2 is a thread support piece, 3 is a thread slide piece, 4 is a sewing needle, 5 is a looper, 6 is a knob, 7 is an advance/retreat lever, 8 is a sewing machine frame, 9 is a guide member, 10 is an elastic member, 11 is a convex portion,
12 is a concave portion, S is a cloth feeding direction, M is a non-working position, and N is a working position.

Claims (1)

[Scope of utility model registration request] A thread support piece that is formed integrally with the throat plate and sets the narrow stitching width, and a needle plate that is arranged in parallel with the thread support piece and sets the thick stitch width with the thread support piece are separate bodies. The width of the thread supporting piece or the width of the thread supporting piece and the thread sliding piece is increased by the cooperative action of a sewing needle that has a thread sliding piece and moves up and down, and a looper that swings in synchronization with the sewing needle. In an overlock sewing machine that forms edge stitches with different overlocking widths defined by lined widths, the thread slip piece is formed at the tip of a retractable rod having a knob at the base in the longitudinal direction, and the retractable rod is , by pressing and supporting the thread slip piece with an elastic member on a guide member fixed to the sewing machine frame,
It is configured to be movable back and forth between an active position provided in parallel with the thread support piece and an inactive position provided on the back side of the needle plate and shifted from the active position in a direction intersecting the cloth feeding direction, and the forward/retractable rod or Either of the elastic members forms a convex portion on one side, and
Overlock sewing machine overlock width switching, characterized in that the other member is formed with a recess that faces the protrusion, so that the advancing and retracting rod and the elastic member can be engaged and held at the action position of the thread sliding piece. Device.