JPS605315B2 - Hem presser foot for sewing machine with cloth cutting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hem presser for a sewing machine with a cloth cutting device.

Conventionally, in green overlock sewing machines that trim the edges of the fabric while sewing, a fixed blade is provided on the throat plate side, and a mounting leg piece that attaches the presser foot to the sewing machine body is linked to the vertical movement of the needle bar. When sewing, the movable blade is moved up and down by the needle so that it slides against the fixed blade, and the edges of the cloth are cut and trimmed. Afterwards, the edges of the cloth were darned.

However, with this conventional structure, the number of parts is large and the structure is complex, so it is not only difficult to install, but also because the fixed blade is attached to the throat plate side. When performing sewing work (for example, normal straight stitching or three-way stitching), it is troublesome to have to replace the entire throat plate or remove the fixed blade one by one. Therefore, the present invention has been made to solve the above-mentioned conventional problems, and uses a conventionally known ordinary throat plate to simplify the structure.
Another object of the present invention is to provide a green presser for a sewing machine equipped with a cloth cutting device that can cut cloth smoothly without using the vertical movement of a needle bar. The present invention will be described below with reference to illustrative embodiments.

Reference numeral a denotes a presser foot for edging the sewing machine, and on the front side of the needle feed hole 11 of the presser foot a, there is a tongue-shaped piece 12a that presses the edge green of the fabric.
A recess 1 into which the base 12b of the presser member 12 is fitted.
3 is formed, and in the center of the recess 13, the base 12b is formed.
A post part 13a is protrudingly provided to fix the post part 13 with iron.
a, the base 12b of the presser member 12 is attached to the tongue-like piece 12.
The needle hole 11 is press-fitted so that the point a is located approximately at the center of the needle hole 11.

In this embodiment, the base 12b of the presser member 12 is held by the presser foot a.
Although the post section 13a protruding from the recess 13 is fixed with iron, it may also be fixed with a pin or the like.
Further, on the front side of the needle insertion hole 11, there is provided a slightly wide upper threading guide groove 14 that extends along the outer surface of the tongue-like piece 12a and opens forward. Reference numeral 15 denotes a blade member, which is inserted into the guide groove 1 with its cutting edge 15a facing upward.
The base end of the elastic member 16 is approximately U-shaped, and is attached to the presser foot material 12 side of the presser foot A so as to be movable up and down via an elastic member 16 made of wire rod. It is iron-coupled to a mounting portion 17 formed on the outside, and is fixed to a bolt 20' via a presser plate 18 and a washer 19.

Further, a notch 15b is formed below the rear end of the blade member 15, and a tongue-shaped piece 1 on the side surface of the base 12b of the presser foot material 12 is formed.
It is adapted to engage with a stopper 21 protruding toward 2a. Therefore, the cutting edge 15a of the blade member 15
The distal end portion 15a is always supported against the throat plate b by the spring force of the elastic member 16. Further, a safety cover 22 is integrally formed in a portion of the base 12b of the holding member 12 where the cutting edge 15a of the blade village 15 is located, so as to cover the cutting edge 15a. Reference numeral 23 denotes a guide plate that guides the cut end c of the cloth c to the outside after it is cut by the blade member 15, and its base end is in front of the needle drop hole 11 of the presser foot a, and A screw 2 is installed on the upper surface of the opposite side of the guide groove 14 to the part where the presser foot village 12 is fixed.
4, the inside of the tip is bent downward along the side green inside the needle drop hole 11, and the bent part 2
The distal end of 3a extends rearward so as to engage with a notch 11a formed at the rear end of the side green of the needle book hole 11.

Reference numeral 25 designates a support piece for attaching to the mounting leg pieces d which are erected on both sides behind the needle drop hole 11 on the upper surface of the presser foot a, and 26 is a locking pin.

Now, when sewing the cloth c, the presser foot a presses the cloth c due to the pressing force of the presser foot (not shown), and the feed dog 2
7 becomes higher than the upper surface of the throat plate b, and when the feed dog 27 moves backward, the cloth c is also sent backward by the amount of movement, but the tip 12a' of the cutting edge 12a of the blade member 12 remains in contact with the upper surface of the throat plate b due to the spring force of the elastic member 16, so that the cloth c is cut by the amount of movement.

(See Figure 5) Reference numeral 28 denotes a needle hole bored in the throat plate b. As described above, according to the present invention, in the fabric presser foot for green stitching, the guide groove for threading the upper thread of the presser foot is made slightly wider, and there is a vertically movable blade on the side surface of the presser foot on the installation side. The blade member is attached, and the tip of the blade member is always in contact with the throat plate, and the cloth is cut according to the amount of cloth fed by the feed dog, so only one blade member is required, and the needle plate and feed dog can also be used. Since the conventional product can be used as is, the structure is simple and installation and removal are easy.

Furthermore, according to the present invention, since the blade member is close to the needle drop hole, it is possible to cut the cloth in a smaller radius compared to a case where the upper and lower cutting blades of the secondary cutter are further away from the needle drop hole. Not only that, but the hem-edge work can be easily performed without requiring any skill.

Furthermore, according to the present invention, the tip of the bent portion of the guide plate is locked in the notch formed at the rear end of the needle drop hole, so the cut edge of the cut cloth is reliably guided to the outside. Therefore, the needle does not shave the incisal edge, so there is no possibility that the incisal edge will become wedged.

Furthermore, the present invention has the advantage that it is possible to easily overseam cloth without cutting the edge by simply aligning the edge of the cloth with the inner surface of the blade member.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a fabric presser foot for overlocking equipped with a fabric cutting device according to the present invention, Fig. 2 is an exploded perspective view of the same, and Fig. 3 is a partially cutaway view of the presser foot showing how the guide plate is attached. Notched side view,
Fig. 4 is a plan view showing the state of use, Fig. 5 is an enlarged side sectional view showing the main parts of the same as above, A shows the case where the feed dog is located within the needle slope, and the mouth shows the case where the feed dog is located on the upper surface of the needle slope. It shows when the cloth is being fed more protrudingly. a is a presser foot for overlocking, 11 is a needle hole, 12 is a presser foot material, 14 is a guide groove, 15 is a blade village, 16 is an elastic member,
21 is a stopper, 23 is a guide plate, 27 is a feed dog, b
is the throat plate, and c is the cloth. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. In a hem presser foot that has a tongue-like piece for pressing the edge of the cloth approximately in the center of the needle hole of the presser foot, the cutting edge is attached to one side of the tongue-like piece of the guide groove on the front side of the needle hole of the presser foot. A blade member facing upward is mounted so as to be movable up and down via an elastic member that always urges the blade member downward, and the blade member is engaged with a notch formed below the rear end of the blade member. A stopper that keeps the tip of the blade member in constant contact with the throat plate is provided protruding from the side of the base of the tongue-like piece, and a stopper is provided on the upper surface of the presser foot on the side opposite to the surface on which the blade member of the guide groove is attached. A hem presser for a sewing machine with a cloth cutting device, characterized in that a guide plate is attached to guide the cut edge of the cut cloth outward in the vicinity of the needle droplet.