JPS5830054Y2 - Cloth cutting device in overlock sewing machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cloth cutting device for an overlock sewing machine, and its purpose is to obtain a cloth cutting device with high durability and good sharpness using extremely simple parts.

The gist of the proposal will be explained using the illustration symbols.

Figure 1 shows an overlock sewing machine with the main shaft placed at the top of the machine frame, viewed from the pulley side, and Figure 2 shows a side view of the overlock sewing machine with the main shaft placed below the bed. This is a simplified diagram showing only the belt hooking system for driving the sewing machine and the cloth cutting knife, and omitting the remaining known mechanisms.

Now, starting from FIG. 1, a pulley 2 provided on the main shaft 1 is driven by a belt 4 hooked around a small pulley 3 of a motor 20, and is connected to a series of members (not shown) such as a needle bar, a looper cloth feeder, etc. ) is exercising.

Now, in the cloth cutting mechanism of the present invention, a lower knife 18 is fixed to the upper part of a wall surface 21 which is a part of the sewing machine frame with screws 16, and a band-shaped upper knife plate 1 having a sickle-shaped blade part 13 on the upper part.
1 are in contact with each other, and the lower end of this female plate is smoothly fitted to an eccentric cam 10 at the left end of a horizontal shaft 9 provided in parallel with the main shaft 1.

Further, a guide pin 14 is fixed to the upper part of the wall surface 21, and is engaged with the vertical slit 12 of the vibrating female plate 11.

There is a small pulley 8 at the right end of this horizontal shaft 9, and this is driven via a belt 6 hooked around the pulley 5 of the motor.

When the motor rotates in this manner, the pulley 8 on the horizontal shaft 9 rotates at a high speed several times the rotation speed of the main pulley 2, and the sickle-shaped blade portion 13 of the female plate has a swing width of about 2 mm. It vibrates in the vertical direction and cuts the fabric sharply in cooperation with the lower knife 18.

As mentioned above, the cloth cutting member of the present invention includes one horizontal shaft, one small pulley 8, one eccentric cam, one strip-shaped upper knife 11, one lower knife 18, and a pressure adjustment spring. Only one piece of 15 and one belt are required, which saves the manufacturing costs of the many parts required to cut fabric with a conventional overlock sewing machine and the frame to support these parts. Drilling, tapping, and the time required for assembly are no longer necessary, significantly improving productivity and leading to cost reductions.

When the belt 6 is not used, the pulley 2 and
It is obvious that a belt 19 may be used between the pulley 8 and the belt 19 for driving.

20 is a tension pulley.

Next, the case of the sewing machine shown in FIG. 2 will be described.

This sewing machine is an overlock sewing machine in which the main shaft 1 and pulley 2 are placed below the bed surface, and the large pulley 2 has two rows of grooves, one row of which is The belt 19 is put around the small pulleys 8 at each end of the horizontal shaft, and the knife 13.11 is vibrated up and down.
Since the text is the same as the explanation with the figures, the explanation will be omitted.

In addition, a bean motor separate from the sewing machine drive motor is provided,
This rotating force may be used to operate the upper knife.

(Not shown) As mentioned above, the cutting device of the present invention requires only a few short, small, and lightweight components, requires less movement, and therefore generates less vibration of the sewing machine, and does not require the upper knife support rod of conventional sewing machines. disappear, and the needle bar and the needle bar on the bed of the sewing machine.
With only the presser foot and a slightly visible sickle-shaped blade, it is compact and has many advantages, such as making it easier to thread the thread into the needle hole.

[Brief explanation of drawings]

Figure 1 is a side view showing the cloth cutting device of the present invention in a type of sewing machine in which the main shaft pulley is installed on the top of the machine frame, and Figure 2 is a side view showing the proposed cloth cutting device in a type of sewing machine in which the main shaft pulley is installed under the bed in the machine frame. FIG. 2 is a side view showing the fabric cutting device of the present invention in the sewing machine.

Claims (1)

[Scope of utility model registration request] The lower knife 18 is fixed to the wall 21 that is perpendicularly downward from the bed surface of the sewing machine frame, and the sickle-shaped blade part 13 at the top of the upper knife is pressed against the lower knife. A guide pin 14 provided on the wall surface is engaged with the directional slit 12, and the lower end of the upper knife is connected to an eccentric cam 10 on a horizontal shaft 9 pivotally supported at the bottom of the sewing machine bed. The small pulley 8 provided on the sewing machine is rotated via a belt hooked to the pulley of the sewing machine drive motor 20, and the sickle-shaped blade of this female is subjected to vertical vibrations that are extremely high in speed compared to the movement speed of the sewing machine needle. A cloth cutting device for an overlock sewing machine, which is characterized by giving the following.