JPS626469B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an overlock sewing machine for overlocking the edges of cloth.

[Conventional technology]

FIG. 5 shows an example of a conventional overlock sewing machine.

In this Fig. 5, 1 is a bed frame, 2 is a bed frame, and 2 is a bed frame.
is the bed above it. This bed 2 has an opening 4 having a needle plate 3 that can be opened and closed.
A fixed knife 5 is attached to the left side wall 6 of the bed frame 1 facing the room.

Reference numeral 8 denotes a lifting rod that is attached to upper and lower guides 9 and 10 so as to be able to rise and fall freely, and a movable knife 11 is fixed to the upper end of the lifting rod.
Trim the edges of the cloth using the blade 13 of No. 1.

The movable knife 11 is attached to the shaft 1 of the guides 9 and 10.
4 and 15 are attached to the left side wall 6 of the bed frame 1 so as to be movable forward and backward, and by pulling the guide 9 to the left with a spring, the movable knife 11 is pressed against the right side surface of the fixed knife 5.

A roller 17 is provided on the side of a block 16 fixed near the bottom of the lifting rod 8, and a two-pronged lever 18 that is linked to the moving part of the sewing machine is engaged with the roller 17, so that the lifting rod 8 is raised and lowered as the sewing machine operates. A mechanism to do so.

Further, the lower looper 32 is fixed to the upper end of a swing lever 34 fixed to a shaft 33 provided on the bed frame 1, and has a shape as shown in FIG.

That is, there is a thread hole 35 on the left side when viewed from the operator, and the thread inserted into this thread hole passes through a thread groove 36 on the front surface of the looper and is inserted into a thread hole 37 at the tip of the looper.

As shown by the chain line in FIG. 5, the front left side of the bed frame 1 is an auxiliary bed 40 that can be opened and closed. , and then open the auxiliary bed 40.

On the other hand, the thread pulled out from the bobbin spool above the sewing machine (not shown) is passed through the thread tension device, thread guide, etc. (not shown) located at the top of the sewing machine, and then passed through the thread guide 4.
1, pass under the fixed knife 5 and throat plate 3, or through the opening 42 in the left side wall 6 of the bed frame 1, and pull it out to the rear of the lower looper 32.

The thread thus drawn out to the rear of the lower looper 32 is passed through the thread hole 35 on the left side of the lower looper 32, passes through the thread groove 36, and is inserted into the thread hole 37 at the tip of the right sword to complete the thread.

[Problem that the invention seeks to solve]

As is clear from the above, inserting the thread into the lower looper 32 is very time-consuming, but in addition to this, the lower looper 32 has a fixed knife 5 and a movable knife 11 at the front.

For this reason, the fixed knife 5 and the parts to which it is attached,
Alternatively, the working field of view is obstructed by the bed frame that supports the fixed knife 5, the bed surface that supports the throat plate 3, and extends forward.

Therefore, when threading the lower looper 32, it is difficult to see it directly, and furthermore, the operator's fingertips cannot sufficiently approach the lower looper 32, making it difficult to thread the thread. Therefore, there was a problem in that the time required to prepare the sewing machine for sewing increased.

In order to solve this problem, the fixed knife and movable knife, which are located in front of the lower looper and which obstruct threading work into the lower looper, and the front part of the bed frame to which both knives are attached, are made into movable parts. When threading, the movable part may be retracted to a non-operating position to open the front of the lower looper, but with such a structure, the driving part of the sewing machine main body and Connection and separation of the movable knife provided in the movable part poses a problem.

[Means for solving problems]

In order to solve the above problems, the present invention provides a swinging member that swings in conjunction with the moving part of the sewing machine on the main body side of the sewing machine, and a swinging member that swings in conjunction with the moving part of the sewing machine. is provided with an engaging member that engages with the swinging member, and when the movable part is moved from the open position to the closed position with respect to the sewing machine main body, the engaging member and the swinging member are functionally connected, and the main body The movable scalpel can be driven by side movement.

[Effect]

Since this invention has the above structure, when threading the lower looper, when the movable part of the bed frame that can be opened and closed is retracted to the inactive position, the swinging member on the sewing machine body side moves from the movable part side. The mating member is disengaged and separated. At the same time, the fixed knife and the movable knife are also retracted from the front part of the lower looper, and the front part of the lower looper is opened, so that the entire lower looper can be directly viewed.

When threading is finished in this state and the movable part is returned to its original closed position, the engaging member on the movable part engages with the swinging member on the sewing machine main body, and the movable knife is driven by the operation of the sewing machine. Become.

〔Example〕

The embodiments shown in FIGS. 1 to 4 are improvements on the conventional example shown in FIG.
A fixed knife 5 and a movable knife 11 are attached to the knife 5.

That is, the movable part 45 rotates around a shaft 46 shown in FIG. 3, and as shown in FIG. be.

Further, as shown in FIG. 3, the shaft 14 of the guide 9 of the lifting rod 8 to which the movable scalpel 11 is attached is inserted into the hole of the attachment part 48 on the rear side of the movable part 45 so as to be able to advance and retreat. The movable knife 11 is crimped to the fixed knife 5 by receiving a spring 49 fitted on the shaft 14 in the large diameter portion at the rear of the shaft 14 by a spring receiver 50 fixed to the rear end of the shaft 14.

The two-pronged lever 18 is a swinging member in this embodiment, and its middle portion is supported by the bed frame 1 by a shaft 51 as shown in FIG.
2, it is connected to a link 53 which is moved up and down via an eccentric.

The roller 17 is an engagement member provided on the movable part side that engages with the two-pronged lever 18 and moves the movable knife 11 by the movement of the sewing machine body.

Further, the front part of the two-pronged lever 18 has slopes a and b that are open up and down so that the roller 17 on the movable part 45 side can easily fit therein, and the lower or upper sides thereof are longer.

Reference numeral 55 in FIGS. 2 to 4 indicates a hook provided on the movable part 45, which is fixed to the inner end of a horizontal shaft 57 rotatably attached to the rear side of the movable part 45. An operating knob 58 is fixed to the outer end.

The hook 55 engages with a locking piece 60 fixed inside the bed frame 1 as shown in FIG. 2. When the movable part 45 is closed, the hook 55 engages with the locking piece 60 under the action of a spring. Further, the hook 55 can be removed from the locking piece 60 by the knob 58.

In this embodiment, when the movable part 45 is closed, the hook 55 engages with the locking piece 60 and is fixed as shown in FIG. 4, and the roller 17 of the lifting bar 8 engages with the two-pronged lever 18. 2, along with the operation of the sewing machine.
The forked lever 18 swings up and down to raise and lower the lifting rod 8, thereby raising and lowering the movable knife 11.

When threading the lower looper 32, the hook 55 is removed from the locking piece 60 using the knob 58, and the movable part 45 is retracted to the front inactive position as shown in FIG. will be released, so
Threading the lower looper 32 becomes extremely easy.

In the above embodiment, the two-pronged lever 18 is used as the swinging member on the sewing machine body side, and the roller 17 is used as the engaging member on the movable part 45 side, but it goes without saying that this combination may be reversed. , and the movable part 4
The retracting method No. 5 may be any other method such as a downward rotating method or a pull-out method in addition to the sideward rotating method as shown in the illustrated example.

〔effect〕

As described above, this invention is designed to move both the fixed knife and the movable knife, which are located in front of the lower looper and which obstruct visibility and become an obstacle to the threading operation when threading the lower looper, to the front together with the movable part of the bed frame. A two-pronged lever that swings in conjunction with the moving part of the sewing machine is provided on the main body side of the sewing machine, that is, on the main body side of the bed frame, and the movable knife provided on the movable part is retracted to a non-working position. The part that moves with the movable part is provided with a roller that engages with the two-pronged lever when the movable part is in the closed position, so when the movable knife and the two-pronged lever on the main body are engaged and disengaged when the movable part is opened and closed, the movable knife In this invention, the inner side of the tip of the two-pronged lever is formed into a slope that opens up and down, so that the closing movement of the movable part is prevented. Even if the roller on the movable knife side and the two-pronged lever are slightly misaligned, the roller will be accurately guided by the inner slope of the two-pronged lever to the correct position, and the engagement between the two-pronged lever and the roller will be ensured. It has the effect of ensuring that things are done properly.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a perspective view of the same movable part as shown in FIG.
The figure is a partially longitudinal rear view showing the rear part of the movable part, Figure 4 is a side view showing the drive mechanism of the movable scalpel, Figure 5 is a perspective view showing the conventional example, and Figure 6 is an enlarged partial cutout of the lower looper. It is a front view. 1...Bed frame, 5...Fixed knife, 11
...Movable knife, 17...Roller, 18...Two-pronged lever, 32...Lower looper, 45...Movable part, a,
b...Slope.

Claims (1)

[Scope of Claims] 1. In an overlock sewing machine having a lower looper and having a fixed knife and a movable knife arranged in front of the lower looper for trimming the edge of the fabric, threading work to the lower looper is performed in front of the lower looper. In an overlock sewing machine, the movable part of the bed frame to which the fixed knife and movable knife are attached, which can be an obstacle to is provided with a swinging member that swings in conjunction with the moving part of the sewing machine, and a locking member that engages with the swinging member to drive a movable knife provided on the movable part when the moving part is in the closed position. A movable knife drive device for an overlock sewing machine, characterized in that a mating member is provided on a movable part side. 2. A movable knife drive device for an overlock sewing machine according to claim 1, wherein the swinging member on the sewing machine main body side is a two-pronged lever, and the engaging member on the movable part side is a roller. 3. The movable knife drive in the overlock sewing machine according to claim 1, wherein the swinging member on the sewing machine main body side has a roller at its tip, and the engaging member on the movable part side has a bifurcated shape. Device. 4. A movable knife drive device in an overlock sewing machine according to claim 2 or 3, wherein the tip of the bifurcated lever has a slope that opens up and down so that the roller can easily fit therein. .