JPH0349657Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of application of the invention) This invention relates to a fabric edge cutting device for a sewing machine. More specifically, the present invention relates to a fabric edge cutting device for a sewing machine that is linked to the needle bar of the sewing machine, can cut fabric edges by utilizing the vertical movement of the needle bar, and can be placed as an independent accessory on the sewing machine bed.

(Prior Art) Regarding the first example of a cloth edge cutting device of this type of sewing machine that has been used conventionally, a swinging arm attached to the needle bar of the sewing machine swings as the needle bar moves up and down. When the lever member is moved, the lever member connected to the swinging arm moves up and down using the pivot point with the support member as a lever fulcrum, and the upper knife attached to the end of the lever member also moves up and down at the same time, causing the upper knife to move up and down. It has a structure in which the edges of the fabric fed into the upper and lower knives are cut by working together with the lower knife blade formed at the end of the base plate facing the upper and lower knives.

Furthermore, as a second conventional example, Japanese Patent Application Laid-Open No. 52-20163
There is a sewing machine fabric edge cutting device described in the issue. .
This cutting device has a fixed blade, a movable blade, a guide piece, etc. mounted on a long and thin L-shaped mounting plate, and these are placed on the upper surface of the throat plate on the sewing machine bed using a conventional presser foot. It is attached and fixed as a unit to the lower end of the presser bar using the same method. The L-shaped mounting plate has a narrow horizontal mounting part and an elongated vertical mounting part, and the front side is formed into a long and narrow L-shape, and a presser foot is fixed to the outside of the vertical mounting part of the mounting plate. A mounting piece for the sewing machine presser bar is integrally formed in a part of the sewing machine.

(Problems to be solved by the invention) In the above-mentioned first conventional example, when attaching the cloth edge cutting device to the sewing machine, the swinging arm is screwed to the needle bar, and at the same time, the entire device is not moved to the sewing machine bed. However, taking into account the relationship with the fabric guide piece installed close to the upper knife, the fabric is moved forward of the upper knife (in the fabric feeding direction) in cooperation with the feed dog. The position of the fabric presser foot, which consists of a presser foot and a presser foot for feeding while pressing, must be considered, so make sure that this fabric presser is placed correctly on the sewing machine bed together with the fabric edge cutting device so that it is suitable for cutting the edges of the fabric. The attachment to the presser bar is laborious and the positioning of this device is made even more difficult, especially due to the presence of the fabric guide piece.

Furthermore, in the second conventional example, the elongated L-shaped mounting plate consists of an elongated narrow horizontal mounting portion and a relatively high elongated vertical mounting portion,
On the side of the vertical mounting part, there is a presser bar mounting piece, a presser foot, an operating lever, an interlocking lever that engages with the presser bar, a group of stepped screws for attaching a cam to this interlocking mechanism, and a group of springs stretched around this stepped screw. is equipped with many parts such as regulating wire springs, and there is a mechanical balance between the narrow rectangular horizontal mounting part and the relatively high and elongated vertical part to which many of the various parts mentioned above are attached. It cannot be removed and is in a so-called head-holding state, and even if it is placed on the throat plate as an independent component in one movement, it is difficult to position it and it is likely to fall over.

Furthermore, the arrangement of the fabric edge cutting device on the throat plate becomes extremely unstable, and when the fabric is fed under the presser foot and the interlocking lever moves up and down to cut the fabric with the fixed blade and movable blade, The entire cutting device is unstable and tends to shift and fall, especially in the left and right directions. This results in defects such as not being able to cut the desired area smoothly, and in order to compensate for this defect, the operator must always pay special attention to keeping the cutting device in place so that it does not fall over, which increases efficiency. This poses a hindrance to the fabric edge cutting work. In other words, this conventional cloth edge cutting device has a defect in its overall structure due to problems in the shape, combination, etc. of its component parts.

The purpose of the present invention is to eliminate the above-mentioned defects and provide a fabric edge cutting device that does not fall over and has good stability when placed on the sewing machine bed. Rather than attaching the main components to the side of the vertical mounting section, the main components are mounted on the wide bottom surface of the support arm (corresponding to the bottom surface of the horizontal mounting section in the conventional example), making the fabric edge cutting device stable on the sewing machine bed. placement has been achieved.

(Means and effects for solving the problem) An upper knife is attached to one end of the second protruding arm of the U-shaped lever member which is pivotally attached to the supporting arm protrusion so as to constitute a predetermined leverage ratio, and the other end of the lever member is attached with a sewing machine. The lower knife plate is connected to a swinging arm that is removably attached to the needle bar, and has a lower knife blade formed at its end that can come into contact with the upper knife blade, and a guide piece whose end is formed on the guide side wall. A second support arm protrudes perpendicularly to the wide bottom surface of the support arm.
The projecting arms are fixed in parallel to each other so as to form the same plane as the bottom surface, and the horizontal part of the L-shaped support plate is attached to the bottom surface of the wide support arm, sandwiching the lower female plate and the guide piece. The second protruding arm protrudes perpendicularly to the wide bottom surface in parallel with the second protruding arm, and is fixed to the wide bottom surface so as to form the same plane as the bottom surface, so that the protruding portion of the L-shaped support plate is parallel to the supporting arm protruding portion. The presser foot is formed into a presser foot that can be attached to a presser bar, and a vertically movable presser foot is pivotally attached to the outside of the presser foot, and the bottom surface of the wide support arm, the lower knife plate, the guide piece, and the L-shaped support plate are horizontal. and a bottom surface of a presser foot pivotally connected to an L-shaped support plate to form a wide bottom surface of a predetermined area, and to provide a cloth edge cutting device for a sewing machine that is stably disposed on a sewing machine bed by the wide bottom surface. It is something to do.

The cloth edge cutting device of the present invention can be attached to the sewing machine bed at once as it is, and can be extremely stably placed on the sewing machine bed without being displaced or swung in the left-right direction when cutting the cloth edge. When performing sewing work with the fabric edge cutting device mounted on the sewing machine bed, there is no need to take into consideration the installation positional relationship with the fabric presser or the wobbling of the fabric edge cutting device, and therefore work efficiency can be improved. can.

(Embodiment) The support arm 4 includes a protrusion 28 and a wide support arm bottom surface 5. The lever member 2 is a protrusion 28 of the support arm 4.
It is pivoted to 6. The lever member 2 is formed in a U-shape, and a first protruding arm 8 at one end thereof is pivotally connected to a swinging arm 12, which will be described later, via a connecting piece 10. Code 16,
18 are screws for pivotally connecting the connecting piece 10 to the first projecting arm 8 and the swinging arm 12, respectively. At the front end of the second protruding arm 20 formed at the other end of the lever member 2, an upper knife 22 having a blade part 24 at its lower end is attached to a screw 26.
Attaches removably. The swinging arm 12 is pivotally attached to one side of the support arm protrusion 28 and the opposite side to the lever member 2 by a screw 30, and one end thereof is connected to the connecting piece 1 as described above.
0 with a screw 18, and forms a U-shaped fork 32 at the other end. The swinging arm 12 is attached to the needle bar 36 at the forked portion 32 by a needle attachment screw 38 of the needle bar 36 having a sewing machine needle 34 attached to the end thereof.
is connected with. . Further, a lower female plate 40 that protrudes parallel to the second protruding arm 20 and forms the same plane as the support arm bottom surface 5 is screwed onto the wide bottom surface 5 of the support arm 4, and the end portion of the lower female plate 40 Upper upper knife blade part 24
The lower knife blade portion 42 is formed with a surface opposite to the lower knife blade portion 42 .

In parallel with the lower female plate 40, a guide piece 54 having a guide side wall 56 integrally erected at its end is parallel to the second protruding arm and forms the same plane as the support arm bottom surface 5, similar to the lower female plate 40. Make it protrude so that it does, and screw it onto the bottom surface 5 of the support arm.

The L-shaped support plate 44 includes a horizontal portion and a protruding portion. A guide piece 54 is installed approximately parallel to the lower female plate 40.
An L-shaped support plate 44 is placed on the bottom surface 5 of the support arm across the support arm.
A horizontal portion of the supporting arm is made to protrude in parallel with the second projecting arm, and this horizontal portion is screwed so as to form the same plane as the bottom surface 5 of the supporting arm.

A protruding end portion of an L-shaped support plate 44 screwed onto the bottom surface of the support arm 4 is formed into a presser leg 46. This presser foot 4
6 is provided to protrude in the same direction as the support arm protrusion 28. Further, the presser foot 50 is attached to the outside of the presser foot 46 so as to be movable up and down by means of a horizontal shaft 48 fitted into the presser foot 46. As mentioned above, the support arm bottom surface 5, the lower knife plate 4
A wide bottom surface of a predetermined area is formed by the guide piece 54, the horizontal part of the L-shaped support plate 44, and the bottom surface of the presser foot 50 pivoted on the outside of the presser leg 46 of the protruding part of the L-shaped support plate. As can be seen from the state shown in FIGS. 4 and 5, the width of the wide bottom surface in the direction orthogonal to the second protruding arm is the same as or shorter than the height of the supporting arm protruding arm 28. The optimum condition is that the length is longer. A needle hole 52 is provided in the presser foot 50. Further, reference numeral 47 is a groove opened on one side formed at the end of the presser leg 46, and is used for fitting the presser bar 62. Reference numeral 49 is a groove used for screwing 60 the presser leg 46 onto the presser bar 62. 58 is a cover member. Push the presser bar 62 of the sewing machine into the groove 47 of the presser foot 46, screw it 60 through the groove 49, and then attach the needle bar 3 to the fork 32 of the swinging arm 12 with the screw 38.
Connect 6.

The vertical movement of the needle bar 36 due to the driving of the sewing machine is converted into the vertical movement of the swing arm 12. When the needle bar 36 rises, the end fork 32 of the swinging arm 12, which is pivotally supported by the screw 30 on the protrusion 28 of the support arm 4, is pulled up, and at the same time, the other end is lowered, and the screw 1
8. Pull down the first protruding arm 8 of the lever member 2 via the connecting piece 10 and the screw 16. On the other hand, the second protruding arm 20 of the lever member 2 rises in the opposite direction to the first protruding arm 8, and the blade portion 2 of the upper knife 22 is attached to the end thereof.
4 moves upward while contacting the blade portion 42 of the lower knife. Next, when the needle bar 36 descends, the swing arm 12 and other related members move in the opposite direction to the above, and the upper knife 22 contacts the blade portion 42 of the lower knife and descends. Therefore, the edges of the fabric fed below the second projecting arm 20 are sheared by the upper and lower knives. The fabric from which the edges have been sheared is fed below the presser foot 50 in the direction of arrow A in FIG. A seam is formed in the fabric by the upper thread and the lower thread pulled up from the bobbin below the presser foot 50. For fabrics with continuous seams as described above, presser foot 5
Although not shown in the figure, the feed is continuously fed in the direction of the arrow by the action of the feed dog. As for the seams, not only lock stitches but also zigzag stitches can be formed on the edges of the fabric.

When the cloth edge cutting device is attached to a sewing machine bed, the presser foot 46 equipped with the presser foot 50 is
The cloth presser can be stably installed on the sewing machine bed in one operation together with the cloth edge cutting device.

(Effects) In the present invention, the main parts are attached to the bottom of the horizontal part of the support arm, and the pivots are attached to the bottom of the support arm, the lower knife plate, the guide piece, the horizontal part of the L-shaped support plate, and the L-shaped support plate. The area of the plane formed by the bottom surface of the attached presser foot is formed to a predetermined size, and the width of the plane in the direction of the second protruding arm is made to be proportional to the height of the supporting arm protrusion. Because of this, the placement on the sewing machine bed is extremely stable, and when the edge of the fed fabric is cut by the vertical movement of the swinging arm, the edge of the fabric supported by the wide plane during sewing. The cutting device has the advantage of being able to carry out efficient cutting work without falling over.

[Brief explanation of the drawing]

FIG. 1 is a side view of one embodiment of the present invention. Second
The figure is a plan view of FIG. 1. FIG. 3 is a schematic rear view of the present invention with the cover member removed. FIG. 4 is a bottom view of FIG. 2. FIG. 5 is a perspective view of FIG. 1. 2... Lever member, 4... Support arm, 5... Support arm bottom, 8... First protruding arm, 10... Connection piece, 12
... Swinging arm, 20 ... Second protruding arm, 22 ... Upper knife, 24 ... Blade section, 32 ... Forked section, 42 ... Lower knife blade section, 44 ... L-shaped support plate, 46...Presser foot, 48...Horizontal shaft, 50...Presser foot, 54...
Guide piece, 62...presser bar.

Claims (1)

[Scope of utility model registration request] An upper knife is attached to one end of the second protruding arm of a U-shaped lever member pivotally attached to the supporting arm protrusion so as to constitute a predetermined leverage ratio, and the other end of the lever member is attached to a swinging member that can be attached to and detached from the needle bar of the sewing machine. A lower knife plate connected to the movable arm and having a lower knife blade formed at an end that can be contacted with the upper knife blade, and a guide piece whose end is formed on a guide side wall are attached to the bottom surface of the support arm. An L-shaped support is provided on the bottom surface of the support arm, with the lower female plate and the guide piece sandwiched between the lower female plate and the guide piece. A horizontal part of the plate is protruded perpendicularly thereto and parallel to the second protruding arm, and fixed so as to form the same plane as the bottom surface of the second protruding arm, and the protruding part of the L-shaped support plate is made parallel to the protruding part of the supporting arm. and a presser foot that can be attached to a presser bar, a vertically movable presser foot pivotally attached to the outside of the presser leg, the bottom surface of the support arm, the lower knife plate, the guide piece, and the horizontal portion of the L-shaped support plate. and the bottom surface of the presser foot pivotally connected to the L-shaped support plate presser foot to form a wide bottom surface of a predetermined area, and the sewing machine is stably disposed on the sewing machine bed by the wide bottom surface. Fabric edge cutting device.