JPS6054078B2 - Cloth edge cutting device in sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fabric cutting device for a sewing machine, and more particularly, to a fabric cutting device for a sewing machine, which automatically cuts the edge of a workpiece fabric before overcutting the fabric fed to a sewing position on a sewing machine bed. The present invention relates to a fabric cutting device.

An object of the present invention is to move a holder equipped with a fixed blade and a movable blade in the longitudinal direction of a sewing machine bed by the cooperative action of a support body and a guide body, so that the holder can be moved between a use position and a storage position. It can be easily placed, and when it is placed in the use position, the locking body temporarily prevents the guiding action of the guiding body, which is an extremely simple operation to prevent the holder from shifting. As a result, at least the movable blade is exposed above the sewing machine bed surface and is securely held in a state where it can cut the edge of the workpiece cloth by cooperation with the fixed blade, and the edge of the workpiece cloth can be smoothly cut in a stable state. A novel fabric cutting device for a sewing machine, which can be easily stored in a narrow space in a sewing machine bed when not in use, and which can be easily embodied in a home sewing machine. Our goal is to provide the following.

An embodiment of the present invention will be described below with reference to the drawings.
Reference numeral 1 in the drawings denotes a sewing machine arm, and as shown in FIG. 1, a sewing machine needle 2 and a presser foot 3 are attached to a needle bar and a presser foot bar attached to the head end of the arm.

Reference numeral 4 denotes a sewing machine bed, on the upper surface of which a top plate 5 is fixed, and on the left side of the front surface a hook lid 6 is attached so as to be rotatable in opening and closing.

7 is a throat plate fixed near the front end of the upper surface of the upper plate 5 so as to cooperate with the upper plate 5 to form a workpiece support surface;
As shown in FIG. 2, a needle hole 7a for zigzag sewing and an opening 7b for a feed dog 8 are formed on the left side, and an opening 7c for a cloth edge cutting device is formed on the right side.

Reference numeral 9 denotes a cover plate that is attached to the opening 7c of the needle plate 7 when the fabric edge cutting device is used, and is located at the left end of the opening 7c adjacent to the fabric feed side of the feed dog 8, as shown by the chain line in FIG. Most of the opening 7c is covered, leaving only the front part slightly.

A separate cover plate 9A is attached to the normal sewing work section where the fabric edge cutting device is not used, which can cover the entire opening 7c of the throat plate 7 by removing the cover plate 9 as shown in FIG. I'm starting to do that. Reference numeral 10 indicates the sewing machine bed 4 so as to extend in a direction perpendicular to the cloth feeding direction of the feed dog 8.
The hook drive shaft in the movement mechanism of the sewing machine is rotatably supported in the sewing machine, and is rotated in conjunction with the main shaft (not shown) of the sewing machine. A drive bevel gear 11 is fixed to.

12 is along the cloth feeding direction of the feed dog 8. As if extending,
A rotating shaft rotatably supported in the sewing machine bed 4, and a driving bevel gear 1 on the hook driving shaft 10 at its rear end.
A driven bevel gear 13 that meshes with the sewing machine needle 2 is fixed, and a hook 1 is attached to the front end of the hook 1 for sewing work cloth in cooperation with the sewing machine needle 2.
4 is equipped. It is worn.

Next, the operating position where only a portion of the sewing machine bed 4 is exposed through the opening 7c of the throat plate 7 and the sewing machine bed 4 are shown.
The structure of the fabric edge cutting device built into the sewing machine bed 4 will be described so that it can be stored in a storage position located below the top surface of the sewing machine bed 4.

Reference numeral 15 denotes a support member in a support mechanism rotatably attached to the inner bottom of the sewing machine bed 4 at its lower end by a support shaft 16 extending parallel to the cloth feeding direction of the feed dog 8;
7 is wound around the support shaft 16 and attached to the sewing machine bed 4 at both ends.
The springs are respectively hooked to the inner bottom and the support body 15, and urge the support body 15 to rotate in the counterclockwise direction in FIG.

Reference numeral 18 denotes a holder rotatably supported at the upper end of the support body 15 by a support shaft 19 at the right end, and as the support body 15 rotates, the feed dog 8 is rotated in the sewing machine bed 4. It is designed to be able to move in a plane almost perpendicular to the cloth feeding direction.

20 is wound around the support shaft 19 and is connected to the support body 15 at both ends.
and springs respectively hooked to the holder 18, which bias the holder 18 to rotate clockwise in FIG.

Reference numeral 21 denotes a guide member having a substantially U-shaped side surface as a guide means fixed to the inner bottom of the sewing machine bed 4 by means of a mounting screw 22 below the holder 18, and is clearly seen in FIGS. 3 and 5. A guide groove 23 is formed in the rear upright piece, and includes a horizontally extending movement guide part 23a and an elevation guide part 23 that slopes downward to the right from the right end of the movement guide part 23a.

Reference numeral 24 is a shaft pin installed between the lower protruding pieces of the holder 18 so as to fit into the guide groove 23, and cooperates with the guide groove 23 to guide the movement of the holder 18 and to control the movement thereof. When the shaft pin 24 is engaged with the left end of the guide groove 23, the holder 18 is moved to the left side where only a part of the upper surface of the left end is exposed above the sewing machine bed surface, as shown in FIG. When the holder 18 is placed in the upper usage position and the shaft pin 24 is engaged with the lower right end of the guide groove 23, the holder 18 is moved to the storage position on the lower right side, which is located below the sewing machine bed surface, as shown in FIG. It is now arranged.

Reference numeral 25 denotes a locking member of a locking mechanism rotatably attached to the holder 18 via a spring washer 26 so as to be located above the guide member 21; As shown in FIG. 2, the operating knob 27 is housed in a recess on the holder 18 and has a pair of recesses 27a on the top surface for finger rests, and is screwed into a screw hole formed in the holder 18 so as to be rotatable and vertically movable. It consists of a threaded rod 28 at its lower end that can engage with the upper end edge of the rear upright piece of the guide body 21.

Then, as shown in FIGS. 3 and 5, the holder 1
8 is moved to the use position, this locking body 25
By rotating the threaded rod 28, the lower end of the threaded rod 28 presses into engagement with the rear upright piece of the guide body 21, and the width of the groove in the movement guide part 23a of the guide groove 23 is reduced, so that the shaft pin 2
The guiding action of the guide groove 23 on the guide groove 23 is temporarily blocked,
The holder 18 can be locked against movement in the use position. Reference numeral 29 denotes a pair of support pins 30 protruding from the rear surface of the front upright piece of the guide body 21.
9a is loosely fitted and is supported on the guide body 21 so as to be movable left and right.
As shown in the figure, a locking piece 29b that can be engaged with the front end of the shaft pin 24 in the guide groove 23 is protrudingly provided at the right end, and an operating piece 29c is bent forward at the left end. has been done.

Reference numeral 31 denotes a spring suspended between the hooking part body 29 and the guide part body 21, and urges the hanging part body 29 to move toward the right.

Then, due to the guiding action of the guide groove 23, the holder 18
When the shaft pin 24 is moved from the use position shown in FIG. 3 to the storage position shown in FIG.
The guide groove 2 is engaged with the arcuate portion of the upper surface of
3, the latching member body 29 moves back to its original position as shown in FIG. is latched and held in the retracted position so as not to be able to move freely. 32 is a fixed blade having a substantially L-shaped front face fixed to the upper surface of the left end of the holder 18, but the holder 18 is moved to the use position as shown in FIGS. 2, 3, and 6. At this time, the blade portion of the fixed blade 32 is positioned close to the needle hole 7a on the cloth feeding side on substantially the same plane as the upper surface of the throat plate 7.

Reference numeral 33 denotes an operating shaft which is rotatably and movably supported in the rear end bearing portion of the holder 18 so as to extend in a direction perpendicular to the cloth feeding direction, and 34 is fixed to the left end of the operating shaft 33. The drive arm extends upward and forward as shown in FIGS. 2 and 6.

35 is a movable blade fixed to the front end of the drive arm 34, and a blade portion and a guide protrusion 35a are formed at the lower end of the movable blade.
When the holder 18 is moved to the use position as shown in FIGS. 3 and 6, only the front end of the drive arm 34 including the movable blade 35 passes through the opening 7c of the throat plate 7 and the upper surface of the sewing machine bed 4. As the operating shaft 33 reciprocates, the movable blade 35 cooperates with the fixed blade 32 to cut the edge of the work cloth being transferred in the cloth feeding direction prior to oversewing. It's summery.

36 is a spring receiver 37 on the operating shaft 33 and a holder 18;
The spring is interposed between the movable blade 35 and the fixed blade 32 and urges the operating shaft 33 to move leftward, thereby constantly pressing the movable blade 35 toward the fixed blade 32.

Reference numeral 38 denotes a movement regulating pin that is movably fixed and protrudes from the left side of the holder 18 so as to come into contact with the right side of the drive arm 34, and is movable blade 3 when cutting thick work cloth.
Even if a rightward movement force is applied to the fixed blade 32 away from the fixed blade 32, the drive arm 34 is prevented from moving in the same direction, and the cutting operation can be performed smoothly.

Reference numeral 39 denotes a thin cloth handling piece attached to the upper surface of the left end of the holder 18 so as to be adjacent to the cutting operation section consisting of the fixed blade 32 and the movable blade 35, and is shown in FIGS. 2 and 3. A standing portion 39a is formed as shown in FIG.
8 is moved to the use position, the cloth handling piece 39 is exposed to the upper surface of the sewing machine bed 4 through the opening 7c of the throat plate 7 together with the movable blade 35 and the front end of the drive arm 34, and the The cloth scraps cut in the cutting operation section are guided to the rear right side along the upright portion 39a of the cloth handling piece 39, and are quickly discharged from the cutting operation section on the upper surfaces of the lid plate 9 and throat plate 7. It's summery.

Reference numeral 40 denotes a bifurcated arm of the operating mechanism fixed to the right end of the operating shaft 3S3 in order to reciprocate the movable blade 35 in conjunction with the movement mechanism of the sewing machine when the holder 18 is moved to the use position. , 41 is an operating cam fixed to the shuttle drive shaft 10 in the sewing machine bed 4 at the rear of the forked arm 40, as is clear from FIGS. 2, 6, 7, and 8. , a large-diameter eccentric operating cam portion 41a into which the biforged arm 40 is fitted in the use position O of the holder 18 and causes the bifork arm 40 to move; A small-diameter portion 41b that faces each other without bending, and an inclined portion 41c that connects the small-diameter portion 41b and the operating cam portion 41a are formed,
Each of these portions 41a, 41b, 41c has a surface 41d having the same radius from the axis of the shuttle drive shaft 10 at a predetermined common angular position.

In this embodiment, a needle fixed position stopping device (
(not shown) is built into the sewing machine, and when the sewing machine is stopped, the operating cam 41 engages with one engaging piece of the bifurcated arm 40 at its surface 41d having the same radius as shown in FIG. It is now stopped in a state where it is stopped.

Therefore, if the holder 18 is moved from the use position to the storage position in this stopped state, the bifurcated arm 40 fitted to the actuation cam 41a of the actuation cam 41 will move as shown in FIG.
One of the engaging pieces is smoothly moved to the right along a surface 41d having the same radius on the operating cam 41, and faces the small diameter portion 41b of the operating cam 41 as shown in FIG. When the holder 18 is moved from the storage position to the use position, the bifurcated arm 40 facing the small diameter portion 41b of the actuation cam 41 has the same radius as that of the engagement piece on the actuation cam 41. The sliding engagement with the surface 41d causes the other engaging piece to move smoothly to the left, and the other engaging piece moves along the inclined portion 41c of the actuating cam 41 on the opposite side to the surface 41d.
1a, and automatically fits into the operating cam portion 41a as shown in FIG. The operation of the sewing machine incorporating the fabric edge cutting device configured as described above will now be described.

Now, in FIG. 4, the holder 18 is moved to the storage position in the sewing machine bed 4, and the opening 7 on the upper surface of the needle plate 7 is opened by the cover plate 9A.
This shows the state where the entire area c is covered.

In this state, the shaft pin 24 at the lower part of the holder 18 is moved within the guide groove 23 of the guide body 21 in the elevation guide portion 23b.
It is located at the lower right end of , and its axis. Since the front end of the pin 24 engages with the lower surface of the latching piece 29b of the latching member body 29, the holder 18 is latched and held in the stored position without being able to move, against the action of the springs 17 and 20 in the support mechanism. has been done. Also, in the storage position of this holder 18, the first 8
As shown in the figure, since the two-pronged arm 40 of the operating mechanism faces the small-diameter portion 41b of the operating cam 41, the operating shaft 33 to which the movable blade 35 is fixed is connected to the shuttle drive shaft 10 in the movement mechanism of the sewing machine.
is dissociated from the connection. Therefore, if the sewing machine is operated in this state, the holder 1 will be removed in the sewing machine bed 4.
With the movable blade 35 stopped, the entire upper surface of the sewing machine bed 4 can be effectively used to perform normal sewing work without fear of the sewing machine 8 rattling. Next, when performing overlock stitching while cutting the edge of the workpiece cloth using the fabric edge cutting device, remove the cover plate 9A on the throat plate 7 and remove the hook cover 6 on the front of the sewing machine bed 4. Open the spring 3 by operating the operating piece 29c to release the latch body 29 from the front opening part L.
When moved to the left against the action of 1, the latching piece 29
b is separated from the shaft pin 24 at the bottom of the holder 18.

As a result, the support body 15 is rotated counterclockwise in FIG. 4 by the action of the spring 17, and the holder 18 is rotated clockwise by the action of the spring 20, so that the shaft pin 24 The holder is moved to the upper left side along the elevation guide portion 23b within the guide groove 23 of No. 21, and then moved to the left along the movement guide portion 23a.
-18 is automatically moved to the use position shown in FIG. On the other hand, when the holder 18 is moved from the storage position to the use position, as shown in FIG. The cam 41 is moved to the left by sliding engagement with a surface 41d having the same radius, and the surface 41d
The other engaging piece on the opposite side is the inclined part 41c of the actuating cam 41.
It rides on the operating cam part 41a along the same line, and automatically fits into the operating cam part 41a as shown in FIG.

Therefore, the operating shaft 33 of the cloth edge cutting device is connected to the shuttle drive shaft 10 in the movement mechanism of the sewing machine, and the movable blade 35 is in a state where it can be reciprocated as the sewing machine is operated. Then, when the operation knob 27 of the locking body 25 is rotated clockwise in the use position of the holder 18, the lower end of the threaded rod 28 presses into engagement with the rear side upright piece of the guide body 21, and the guide body 25 is rotated clockwise. The groove width at the movement guide portion 23a of the groove 23 is reduced, and the guiding action of the guide groove 23 on the shaft pin 24 is temporarily blocked.

Therefore, the holder 18 is locked so that it cannot move in the use position, and in this state, the lid plate 9A is inserted into the opening 7c of the throat plate 7.
If a separate cover plate 9 is attached, only the front end of the drive arm 34 including the movable blade 35 and the cloth handling piece 39 will protrude above the upper surface of the sewing machine bed 4, as shown in FIGS. 1 and 3. , most of the holder 18 is covered by the cover plate 9. Therefore, if the sewing machine is operated in this state, as the hook drive shaft 10 rotates, the movable blade 35 will move through the operating cam portion 41a1 of the operating cam 41, the bifurcated arm 40, the operating shaft 33, and the driving arm 34. The movable blade 35 and fixed blade 3 are reciprocated.
The edge of the work cloth being transferred in the cloth feeding direction is cut by the cooperation of the sewing machine needle 2 and the hook 14, and an overlock stitch is performed by the cooperation of the sewing machine needle 2 and the hook 14 immediately after the cutting operation section. Also, during this sewing work, hold holder 1 as described above.
Since most of the upper part of the cloth handling section 8 is covered by the cover plate 9, there is no danger that the cloth waste generated in the cutting operation section will stagnate in the vicinity thereof, and will be guided to the rear right side along the upright section 39a of the cloth handling piece 39. It is quickly discharged from the cutting operation section at the upper surfaces of the lid plate 9 and needle plate 7.

Therefore, it is possible to easily and accurately cut the edges of the fabric and overseam without being hindered by fabric scraps. Next, a case will be described in which the cloth edge cutting device is stored in the sewing machine bed 4 again.

In this case, first remove the cover plate 9 from the state shown in FIG. 3 and rotate the operating knob 27 of the locking body 25 counterclockwise in almost the reverse order of the operation during use as described above. The pressure engagement of the screw rod 28 with the rear upright piece of the member 21 is released, and the shaft pin 24 at the lower part of the holder 18 becomes able to move along the guide groove 23 of the guide member. Thereafter, when the holder 18 is moved to the right from the use position shown in FIG. 3 by placing a finger on the protruding portion of the movable blade 35, etc., and is pressed downward from the predetermined movement position, the shaft pin 2
4 moves along the guide groove 23 from the left end to the lower right end, and the holder 18 is placed in the storage position in the sewing machine bed 4 shown in FIG. When the holder 18 is moved, when the shaft pin 24 moves downward to the right side along the elevation guide portion 23b of the guide groove 23, the front end of the shaft pin 24 is bent into a circular arc on the upper surface of the locking piece 29b of the locking portion body 29. by engaging the
With the hook body 29 moved to the left, the guide groove 23
After that, the locking member 29 moves back to its original position as shown in FIG. 4, and the lower surface of the locking piece 29b engages with the front end of the shaft pin 24. Therefore, the holder 18 is locked and held in the retracted position so as not to be able to move. On the other hand, when the holder 18 is moved from the use position to the storage position, as shown in FIG.
One of the engaging pieces of the two-pronged arm that is fitted in the part a is moved to the right along a surface 41d having the same radius on the operating cam 41, and as shown in FIG. Small diameter part 41
relative to b.

Therefore, the connection between the operating shaft 33 of the cloth edge cutting device and the shuttle drive shaft 10 in the movement mechanism of the sewing machine is disengaged, and in this state, the lid plate 9A that covers the entire opening 7c of the throat plate 7 is attached. For example, as shown in FIG. 4, the sewing machine is in a state where normal sewing work can be performed. Note that the present invention is not limited to the configuration of the above-mentioned embodiment, but for example, the configuration of the support mechanism and the guide means may be changed so that almost the entire upper surface of the holder is exposed above the sewing machine bed surface when the holder is in use position. Or, the configuration of the operating mechanism may be changed so that the movable blade moves back and forth while being connected to the movement mechanism of the sewing machine even when the holder is in the retracted position, or the holder, support body, guide body, The structure of each part can be changed arbitrarily without departing from the spirit of the present invention, such as changing the specific structure of the locking body or the operating mechanism.

As is clear from the above description, according to the present invention, the holder on which the fixed blade and the movable blade are attached is moved in the longitudinal direction of the sewing machine bed by the cooperative action of the support body and the guide body, as necessary. The holder can be easily placed in the use position and storage position, and when placed in the use position, the locking part temporarily blocks the guiding action of the guide part, which is an extremely simple operation. By preventing the movement of the movable blade, at least the movable blade is exposed above the sewing machine bed surface and is securely held in a state where it can cut the edge of the workpiece cloth by cooperation with the fixed blade, and the workpiece cloth is kept in a stable state. It is an excellent product that can cut the edge of the sewing machine smoothly, and can be easily stored in a narrow space inside the sewing machine bed when not in use. be effective.

[Brief explanation of the drawing]

Fig. 1 is a partial perspective view of a sewing machine showing the state in which a fabric edge cutting device embodying the present invention is used; Fig. 2 is a partial plan view of the sewing machine bed with the cover plate removed; 2 is a sectional view taken approximately at line 3-3 in Fig. 2, Fig. 4 is a sectional view showing a state in which the fabric edge cutting device is stored in the sewing machine bed from the state shown in Fig. 3, and Fig. 5 is a sectional view taken approximately at line 3-3 in Fig. 3. 6 is a sectional view taken approximately at line 6-6 in FIG. 3, FIG. 7 is a partial sectional view taken approximately at line 7-7 in FIG. 2, and FIG.
This figure is a partial sectional view showing a state in which the cloth edge cutting device is stored in the sewing machine bed from the state shown in FIG. 7. Sewing machine bed...4, Throat plate...7, Hook drive shaft...10, Support body...15, Holder...18, Guide Body...21, Guide groove...23, Shaft pin...2 Male locking body...
...25, Operation knob ...27, Screw rod ...28, Fixed blade ...32, Operating shaft ...
...33, Drive arm...3 movable blade...
35, Bifurcated arm...40, Operating cam...
41.

Claims (1)

[Claims] 1. The fixed blade 32 is fixed, and the fixed blade 32
A holder 18 on which a movable blade 35 is reciprocatably mounted for cutting the work cloth in cooperation with the holder 18 and a fixed axis 16 in the sewing machine bed 4 extending in a direction perpendicular to the longitudinal direction of the sewing machine bed 4. A support body 15 that is rotatably mounted and rotatably supports the holder 18 at its free end, and at least the movable blade 35 are exposed above the sewing machine bed surface to cut the edge of the work cloth. The position and its movable blade 35
The holder 18 is engaged with a portion of the holder 18 that is remote from the support end of the holder 18 supported by the support body 15 so that the holder 18 can take a storage position located below the surface of the sewing machine bed 4. A guide member 21 is provided with a guide groove 23 for guiding the movement of the sewing machine bed 4 and extends in the longitudinal direction of the bed 4. A locking body 25 is attached to the holder 18 and is manually operable to act on the guide groove 23 to temporarily block the guiding action of the guiding body 21, and a locking body 25 is attached to the movable blade 35 at least in the use position. An operating mechanism (such as 40) is provided for reciprocating movement in conjunction with the movement mechanism of the sewing machine, so that the holder 18 is locked in its use position without any movement by manual operation of the locking body 25. A fabric edge cutting device for a sewing machine, which is characterized by: 2. The locking part body 25 is press-fitted to the guide part body 21, and the movement of the holder 18 is prevented by temporarily reducing the width of the guide groove 23. A fabric edge cutting device in a sewing machine according to scope 1.