JP2762064B2 - sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine, and more particularly to a sewing machine suitable for sewing a knitted fabric (knitted fabric) having continuous stitches and having high elasticity, and a fabric having no stitches.

[0002]

2. Description of the Related Art A knitted fabric is manufactured by knitting yarns with knitting needles (knitting rods), so that a large number of stitches are continuously entangled and have high elasticity. When sewing such a knit fabric to produce a knit product such as a sweater, a sewing machine dedicated to the knit fabric is used. As shown in FIG. 13, this dedicated sewing machine includes a needle plate 82 in which a large number of locking needles 81 are arranged in a comb-like shape at a constant pitch. As shown in FIG. 14, the locking needle 81 includes a locking portion 81a and a fixing portion 81.
The fixing portion 81b is fixed to the back surface of the needle plate 82 by welding or the like. The tip of the locking portion 81a is sharply pointed, and a guide groove 81c is formed on the front surface thereof. Then, as shown in FIG. 15, the respective end loops 83a of one knitted fabric 83 are sequentially skewed to the respective locking needles 81 of the needle plate 82, and the respective end loops 84a of the other knitted fabric 84 are turned in opposite directions. After skewing in order from the side, move the sewing needle 85 up and down to
Stitch between 83a and 84a.

That is, when the sewing needle 85 descends from the top dead center toward the bottom dead center, the needle tip advances along the guide groove 81c of the locking needle 81, and the end loop of both knit fabrics is formed. 83a,
Pass between 84a. The sewing needle 85 enters below the bed 86 through a hole 86a formed in the surface of the sewing machine bed 86,
The needle thread of the wedge-shaped looper 87 is applied to the sewing thread inserted through the thread hole of the needle tip.
Guide to around 87a. The looper 87 is rotating in a fixed direction, and when the sewing needle 85 enters a returning process upward, the sewing thread is caught by the blade point 87a to form a loop, and until the sewing needle 85 comes down again. While holding this, a chain-shaped seam is formed by passing a sewing thread through the loop, whereby stitching of both knit fabrics 83 and 84 is realized.

The needle plate 82 is engaged with a relatively long mounting table 88 arranged on the front side of the bed 86 and orthogonal to the sewing machine main body. That is, a guide rail 89 is attached to the back surface of the needle plate 82 (FIG. 14).
The needle plate 82 is slidable in the horizontal direction on the mounting table 88 by fitting the 89 into the guide groove 88a formed in the mounting table 88. Further, a feed gear 90 is disposed below the needle plate 82, and the feed gear 90 is engaged with a fixing portion 81b of a locking needle 81 arranged in a rack shape on the back surface of the needle plate 82. . The feed gear 90 is connected to a drive source of the sewing needle 85 via another gear 91 or a conductive means such as a belt (not shown), and is configured to rotate in synchronization with the vertical movement of the sewing needle 85. I have. That is, every time the sewing needle 85 reciprocates one time, the needle plate 82 slides by one pitch, and the next locking needle
81 moves immediately below the sewing needle 85. Also, the above looper 87
The sewing machine 85 is also connected to the drive source via a transmission mechanism (not shown) so as to make one rotation in synchronization with the vertical movement of the sewing needle 85.

[0005] As described above, since the knitted fabrics 83 and 84 are stitched together with a single thread in a chain shape, a constant elasticity is ensured also at the stitched portions of the knitted fabrics. Characteristics can be well matched. In addition, since the terminal loops 83a and 84a of each knitted fabric are carefully pierced and sewn into the locking needle 81 of the needle plate 82, the terminal loops are neatly aligned at the sewn portion, and the design effect can be enhanced. Of course, it is possible to effectively prevent the knitted fabric from unraveling from the end portion.

On the other hand, in the case of suturing ordinary cloth having poor stretchability, a so-called lockstitch sewing machine is used to lock the upper thread and the lower thread. In this lock stitch, unlike the above-described stitching with a single thread in a chain shape, the seam is firmly fastened and has no elasticity. In the case of suturing fabrics that do not inherently have elasticity, regular sewing without elasticity is better.

[0007]

However, depending on the function and design of the garment, it may be necessary to sew a stretchy knitted fabric and a fabric with poor stretchability. For example,
The case in which a cuff of a knitted fabric is sewn to the end of a sleeve portion of a nylon blouson, or the case in which a fabric such as cotton is treated as a part of a knitted sweater to provide an accent in design. In such a case, if the above-described sewing machine dedicated to the knitted fabric is used, the stitches can be caught by the locking needle 81, so that the stitches (end loops) can be aligned at the sewn portions, and the characteristics of the knitted fabric can be utilized. However, if a finely woven fabric is pierced into the locking needle 81, the weaving thread is cut and a hole is created.If the poorly stretchable fabric is sewn with stretchable chain stitching, Since many fine wrinkles are generated on the side, a sewing machine dedicated to knitted fabric cannot be used.

[0008] For this reason, conventionally, stitching between a knitted fabric and a fabric has been realized by a lockstitch sewing machine used for sewing a fabric with a fabric. Indeed, if a lockstitch sewing machine is used, a dense and strong seam is formed by the entanglement of the upper thread and the lower thread, so that fine wrinkles do not adhere to the fabric side. However, the lockstitch sewing machine naturally has no locking needle and cannot stitch the stitches of the knitted fabric carefully. For this reason, the loops at the end of the knitted fabric cannot be aligned neatly, and not only the bent end loop cannot be utilized in the design, but also the yarn may be unraveled from the end. Therefore, as shown in FIG. 16, when the knitted fabric 83 and the fabric 92 are sewn with the lockstitch sewing machine, the lockstitching process is not performed in a state where the vicinity of the end of the knitted fabric 83 is double-folded inward. Did not get. In this way, even if the terminal end portion comes loose, the sewing stops at the seam 93, so that the surface of the knitted fabric 83 can be prevented from being damaged. However, since the thick knitted fabric 83 is simply doubled, the thickness of the doubled knitted fabric 83 is increased to make it look like a joint, and natural integration with the cloth 92 is hindered. For this reason, a great constraint was imposed on the design of the clothing.

The present invention has been devised in order to solve the above-mentioned conventional problems, and when sewing a knitted fabric to a fabric, the stitches on the knitted fabric side can be reliably picked up. It is possible to align beautiful stitches at the stitched part, and there is no danger of unraveling even if the end of the knitted fabric is not double-folded, and there is no damage to the fabric at the time of sewing or fine wrinkles on the fabric side Don't drop in,
An object of the present invention is to provide an ideal means for suturing a knitted fabric and a fabric.

[0010]

A sewing machine according to the present invention comprises:
A sewing needle having a needle hole through which an upper thread is passed and arranged reciprocally in the up and down direction, a shuttle having a sword point and a lower thread housed therein, and being arranged to be able to rotate fully or half a turn; A sewing machine body having a drive mechanism for realizing a continuous reciprocating movement of the sewing needle and a continuous rotation movement of the shuttle, and a stitch for piercing a stitch of a knitted fabric which is attached to the sewing machine body and is one of the sewing objects. A needle plate in which a number of locking needles are arranged in a comb-tooth shape at a predetermined pitch, and a cloth fixing means mounted on the back surface of the needle plate and fixing the other cloth to be sutured to the back surface of the needle plate. The sewing needle is lowered along the locking needle of the needle plate with the upper thread passed through the needle hole, and penetrates the stitches and fabric of the knitted fabric and places the upper thread near the blade point of the shuttle. After the supply, the kettle turns upward and the upper hook captures the upper thread with The stored lower thread is tied to the upper thread to form a lockstitch seam, and the needle plate is formed each time one stitch is formed by the reciprocation of the sewing needle and the rotation of the shuttle. The locking needle is driven so as to be fed by one pitch. In addition, the above "fabric" is cotton, silk,
This concept widely includes sewing materials other than knitted fabrics, such as synthetic leather and real leather, as well as woven fabrics made of wool, synthetic fibers, and the like.

As described above, the sewing machine according to the present invention is provided with the needle plate in which a large number of locking needles are arranged in a comb shape, so that the stitches of the knitted fabric can be reliably captured, and the terminal loop and the fabric Can be reliably sewn. As a result,
Not only can the end loop unique to the knitted fabric be aligned neatly at the joint between the knitted fabric and the fabric, but there is no worry that the end of the knitted fabric can be unraveled without having to be double-folded as before. It is possible to finish the joint portion with the fabric in an extremely thin state with almost no change in thickness. In addition, the stitching of the knitted fabric and the fabric is realized by the lockstitch that securely binds the upper thread and the lower thread,
Since the seam does not expand or contract, there is no danger of fine wrinkles on the fabric side. Furthermore, since the fabric side is fixed at the fabric fixing part, there is no need to pierce the fabric with the locking needle,
The fabric is not damaged during fixing.

Another sewing machine according to the present invention includes a sewing needle having a needle hole through which a sewing thread passes, and a sewing needle arranged reciprocally in the up and down direction, a looper having a sword point and arranged rotatably, and the sewing machine described above. A sewing machine body having a drive mechanism for realizing a continuous reciprocating movement of the needle and a continuous rotation movement of the looper; and a large number of stitches mounted on the sewing machine body for piercing a stitch of a knitted fabric to be sewn. A needle plate in which the locking needles are arranged in a comb shape at a predetermined pitch, and cloth fixing means mounted on the back surface of the needle plate and fixing the other cloth to be sutured to the back surface of the needle plate. The sewing needle is lowered along the locking needle of the needle plate while the sewing thread is passed through the needle hole, and after supplying the sewing thread near the sword tip of the looper through the stitch and fabric of the knitted fabric. Turning to the rise, the above looper
The sewing thread is captured by the point of a sword through a rotary motion to form a loop, and a loop-shaped seam is formed in the loop through the sewing thread carried through the next descending stroke of the sewing needle. Each time one stitch is formed by the cooperation of the reciprocating motion and the rotation of the looper, the locking needle is driven so as to be fed by one pitch.

[0013] Even if the fabric has no stitches, some fabrics have elasticity (for example, synthetic leather with elasticity). In the case of suturing, the upper thread and the lower thread are entangled with each other to form a lockstitch seam.
It is more suitable to use a looper that can form a chain stitch having elasticity using a book sewing thread. Even in this case, since the needle plate is provided with a large number of locking needles arranged in a comb shape, the stitches of the knitted fabric can be reliably captured, and the terminal loop and the fabric can be securely stitched. Can be. Further, since the fabric side is fixed by the fabric fixing means, it is not necessary to pierce the fabric with the locking needle, and the fabric is not damaged during fixing.

The locking needle is formed in an L-shape having a locking portion vertically provided from the surface of the needle plate and a fixed portion arranged in parallel with the surface of the needle plate. It is desirable that the portion is buried in a groove formed on the surface of the needle plate. The cloth fixing means includes, for example, a pressing plate disposed on the back side of the needle plate, and an urging means for urging the pressing plate toward the back side of the needle plate, and a part of the cloth is formed on the back surface of the needle plate. It is configured so as to be sandwiched between the side and the holding plate and fixed. A spring such as a coil spring or a leaf spring corresponds to the urging means. Alternatively, a magnet may be employed as the urging means.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a sewing machine according to the present invention will be described below with reference to the accompanying drawings. FIG.
Shows the overall configuration of the sewing machine 10.
Is a sewing machine main body 14 including an arm 11 which is passed substantially horizontally, a bed 12 parallel to the arm 11, a pillar 13 connecting the arm 11 and the bed 12, and a needle plate mounted near the tip of the bed 12. It consists of 15.

At the end of the arm 11, a head portion 16 having a substantially U-shaped side surface is formed, and a needle bar 17 is fixed to the head portion 16 so as to be vertically movable. .
A threading hole 18 is formed near the upper end of the needle bar 17. An engaging member 19 is attached in the middle of the needle bar 17, and a threading bar 20 having a threading hole 18 protrudes from a distal end surface of the engaging member 19. A sewing needle 21 is fixed to a lower end of the needle bar 17 with a screw 22. An eaves-shaped threading member 23 having a threading hole 18 is provided on an upper end surface of the head portion 16.
Is attached. On the upper surface of the arm 11, a plurality of thread guide rods 24 each having a threading hole 18 near the upper end are provided upright. On the upper surface of the arm 11, a pair of plate members 25a,
A thread tensioner 25 having a spring 25c and a spring 25c is arranged. The upper thread for sewing unwound from the bobbin 26
27 is each thread guiding rod 24, needle bar 17, threading member 23, threading rod
Through the respective threading holes 18 of 20, the needle is guided to a needle hole 28 formed at the tip of the sewing needle 21. Also, the upper thread 27 has a spring
Plate members 25a, 25b of the thread tensioner 25 pressurized by 25c
By passing through the gap, an appropriate tension is applied. A flywheel 30 with a handle 29 attached to the column 13
Is rotatably mounted on the shaft.

The needle plate 15 is made of a lightweight and robust aluminum alloy or the like. As shown in FIG. 2, a locking needle 31 is fixed on the surface thereof. The locking needle 31 is erected substantially vertically from the surface of the needle plate 15 and has a sharply pointed locking portion 31a, and a fixed portion disposed substantially horizontally with the surface of the needle plate 15.
31b. The lower half of the fixed portion 31b of the locking needle 31 is embedded in a groove 15a formed on the surface of the needle plate 15. The fixing between the locking needle 31 and the needle plate 15 is realized by welding the fixing portion 31b of the locking needle into the groove 15a of the needle plate. Alternatively, after the locking needle 31 is temporarily fixed in the groove 15a of the needle plate, molten solder may be flowed over the surface of the needle plate 15 and soldered. As shown in FIGS. 3 and 4, on the surface of the needle plate 15, a large number of locking needles 31 are arranged at regular intervals in a comb-tooth shape. Further, the needle plate 15 has an elongated through slit 32 for entry of the sewing needle 21 along an end portion (a boundary portion between the locking portion 31a and the fixing portion 31b) of each locking needle 31. . A groove 31c for guiding the sewing needle 21 is formed on the front surface of the locking portion 31a of the locking needle 31 (FIG. 4).

As shown in FIG. 5, a guide rail 33 and a rack 34 extending along the longitudinal direction of the needle plate 15 are attached to the back surface of the needle plate 15. Further, a first fabric fixing portion 35 is attached to the back surface of the needle plate 15. As shown in FIG. 6, the first fabric fixing portion 35 has a structure almost common to a binder used for binding documents and the like, and includes a substrate 36 embedded on the back surface of the needle plate 15 and a A holding plate 37 arranged substantially parallel to the substrate 36, and a plurality of rods 38a,
38b and 38c. A rod 38b located at the center of the rod is formed by one end of a coil spring 39, passes through a bearing piece 40, and is rotatably fixed to an outer surface side of a holding plate 37 via a bearing plate 41. I have. The other end of the coil spring 39 is fixed to the lever 42. An annular portion of the coil spring 39 is rotatably inserted into a shaft 43 passed between the substrate wall portion 36a and the bearing piece 40. Other rod
38a and 38c have one end rotatably inserted between the substrate wall portion 36a and the bearing piece 40, and the other end has a bearing plate 41.
And is rotatably fixed to the outer surface side of the holding plate 37 via the. A base end of the lever 42 is rotatably mounted on the shaft 43. A rubber 44 for preventing slippage is attached to the inner surface of the holding plate 37.

In the state shown in FIG. 6, the substrate 36 and the holding plate 37
When the lever 42 is rotated in the direction of the arrow, the rods 38a, 38b, 38c also rotate in the same direction, and the gap is narrowed. Part 42a
Is engaged with the projection 45 formed on the wall portion 36a, whereby the inner surface (rubber 44) of the holding plate 37 is locked in a state of being in close contact with the substrate 36. As mentioned above, the middle rod 38b
Is constituted by one end of a coil spring 39, and the other end of the coil spring 39 is fixed to the inner surface of the lever 42. Therefore, when the lever 42 is locked, an appropriate pressure is applied from the holding plate 37 side to the substrate 36 side. Becomes

As shown in FIG. 2, a first concave portion 46 and a second concave portion 47 are formed at the tip end of the bed 12. In addition, a mounting table 48 is installed at the foremost portion of the bed 12 so as to be substantially orthogonal to the sewing machine main body 14 (FIG. 3). Reference numeral 49 in FIG. 1 indicates a bracket for supporting the mounting table 48. The needle plate 15 is provided with the first
The sewing machine body 14 is closed in such a manner that the recess 46 and the second recess 47 are closed.
Attached to. That is, the rack portion 34 on the back surface of the needle plate 15 is positioned just near the opening of the second concave portion 47, and the first fabric fixing portion 35 is positioned so as to be housed in the first concave portion 46. The guide rail 33 on the back surface of the needle plate 15 is slidably fitted in the guide groove 48a of the mounting table 48.

A lower shaft 50 protrudes from the wall surface of the first concave portion 46, and a fully-rotatable shuttle 51 is attached to the tip of the lower shaft 50. The shuttle 51 has a structure substantially common to that used for a so-called lockstitch sewing machine, and includes an outer shuttle having a sword point, and an inner shuttle having a bobbin wound with a bobbin thread detachably stored therein. Because the configuration itself is well known,
Detailed description is omitted.

The lower shaft 50 extends through the inside of the bed 12 to the column 13 side, and passes through a hollow portion 52 formed inside the bed 12 on the way. In the hollow portion 52, a first gear 53 and a second gear 54 meshed with the first gear 53 are rotatably arranged. Further, a projection 55 is formed on the lower shaft 50, and the projection 55 is rotated so as to mesh with the first gear 53 when the lower shaft 50 rotates. Shaft of the second gear 54
56 goes through the inside of the bed 12 toward the tip side,
It is connected to a third gear 57 rotatably arranged in the second recess 47. Further, the third gear 57 is meshed with a fourth gear 58 which is also rotatably arranged in the second recess 47. Therefore, when the second gear 54 rotates, the third gear 47 and the fourth gear 58 rotate in response. And the fourth gear 58 is formed by the above-mentioned needle plate.
15 meshes with the teeth of a rack portion 34 formed on the back surface. As a result, the rotation of the lower shaft 50 causes the hook 51 to
When rotated, the projection 55 rotates the first gear 53 by one pitch, and the rotational movement of the first gear 53 causes the second gear 54, the shaft 56, the third gear 57, and the fourth gear 58 to rotate. The needle plate 15 is slid through the needle plate 15 by one pitch (for one locking needle). Although not shown, it is desirable to mount a reverse rotation prevention mechanism on any of the gears.

As shown in FIG. 7, an internal tooth 59 is formed on the inner peripheral surface of the flywheel 30, and the fifth gear 60 and the sixth gear 60 are formed.
Gear 61 is meshed with the internal teeth 59. Therefore, by turning the handle 29 attached to the outer periphery of the flywheel 30 and rotating the flywheel 30 about the shaft 62, the internal teeth
The fifth gear 60 and the sixth gear 61 rotate in the direction of the arrow in FIG.

As shown in FIG. 8, the fifth gear 60 is connected to an upper shaft 63 passing through the inside of the arm 11. A disk 64 is formed on the tip side of the upper shaft 63, and the disk 64
An engagement pin 65 is connected to the periphery of the surface of the 64. The engagement pin 65 is provided with the engagement member 19 attached to the needle bar 17.
In the recess 19a. Then, when the upper shaft 63 rotates and the disk 64 rotates, the engaging pin 65 moves up and down along a circumferential trajectory around the upper shaft 63. Since the concave portion 19a of the engaging member 19 is formed to be relatively laterally long, the engaging pin 65 rotates while sliding left and right in the concave portion 19a, and as a result, the rotational movement of the disc 64 is reduced. This is converted into a vertical reciprocating motion of the needle bar 17. On the other hand, the sixth gear 61 is connected to the lower shaft 50 penetrating through the inside of the bed 12. As described above, the shuttle 51 is connected to the tip of the lower shaft 50, and the projection 55
Are formed. When the lower shaft 50 rotates, the shuttle 51 rotates. When the shuttle 51 makes one rotation, the fourth gear 58 rotates through the first gear 53, the second gear 54, and the third gear 57. The sliding of the needle plate 15 by one pitch is as described above.

Next, a specific method of using the sewing machine 10 will be described. First, one end loop 66a of one knitted fabric 66 to be sewn is carefully pierced one by one into each locking needle 31 of the needle plate 15 (FIG. 4). Next, as shown in FIG. 6, the other side of the cloth 67 to be sewn is sandwiched between the holding plate 37 of the first cloth fixing portion 35 and the substrate 36, and the lever 42 is locked. Thereby, one end of the fabric 67 is firmly fixed to the back surface of the needle plate 15. In addition, the first fabric fixing portion exemplified here
35 is narrower in width than the entire length of the needle plate 15,
When the cloth 67 is fixed over the entire length of the needle plate 15, it is desirable to provide a plurality of first cloth fixing portions 35 on the back surface of the needle plate 15. Of course, the first cloth fixing portion 35 having a width substantially equal to the entire length of the needle plate 15 may be provided. As described above, the knit fabric 66 is placed on the front side of the needle plate 15 and the fabric 67 is placed on the back side.
Then, the needle plate 15 is attached to the end of the bed 12 of the sewing machine 10 (FIG. 2). At this time, as shown in FIG.
A portion 67 a on the side of the end of 67 is exposed from the slit 32 of the needle plate 15. Further, a part 67b of the dough following this is sandwiched between the overhanging edge 15b of the needle plate 15 and the sliding surface 68 of the bed 12 (FIG. 2). The surface of the knit fabric 66 has a head
A presser wheel 69 attached to 16 is arranged and pressure is applied from above (FIG. 2).

In this state, when the handle 29 is rotated in one direction, the sewing needle 21 linked to the upper shaft 63 starts reciprocating up and down, and the shuttle 51 connected to the lower shaft 50 starts rotating. . Then, when the sewing needle 21 having the upper thread 27 passed through the thread hole 28 at the tip thereof, the needle tip of the sewing needle 21 moves along the guide groove 31c formed in the engagement needle 31, and the knit fabric 66 Through the end loop 66a of the needle plate 15 to the slit 32 of the needle plate 15.
Then, the sewing needle 21 is attached to the cloth
It passes through 67 (67a) and descends to the vicinity of the shuttle 51, where it starts to rise. When the sewing needle 21 rises, the blade point of the shuttle 51 catches the upper thread 27, and in the course of its rotation, unwinds a lower thread (not shown) housed inside the shuttle 51 and entangles it with the loop of the upper thread 27, The so-called lock stitches are formed. In this way, the sewing needle 21 executes one descent-elevation cycle, during which the shuttle 51 makes one rotation, so that the knit fabric 66 and the fabric 67
Is completed for one stitch. And sewing needle
The fourth gear 58 is rotated by one tooth and the needle plate 15 is slid by one tooth of the rack portion 34 at a timing immediately before the 21 moves to the next descending operation. Therefore, when the sewing needle 21 is lowered again, the needle tip moves along the guide groove 31c of the next locking needle 31. That is, if the handle 29 is continuously rotated in one direction,
The suturing of the knitted fabric 66 and the fabric 67 proceeds automatically.

The pitch of the locking needles 31 of the needle plate 15 is determined according to the density of the stitches of the knit fabric 66 to be sewn, and the feed width of the needle plate 15 is determined correspondingly. It is. Therefore, when sewing a knitted fabric with a fine stitch, a needle plate 15 in which the locking needles 31 are densely arranged is used, and the needle plate 15 is sent with a small width. On the other hand, when sewing a knitted fabric with a coarser stitch, a relatively large space between the locking needles 31 is secured,
This needs to be sent in a large width.

By using the sewing machine 10 according to the present invention,
The following advantages result. First, since the needle plate 15 in which a large number of the locking needles 31 are arranged in a comb shape is provided, the terminal loops 66a of the knitted fabric 66 can be reliably captured, and the terminal loops 66a and the fabric 67 can be securely stitched. can do. Therefore, FIG.
As shown in (5), the terminal loop 66a of the knitted fabric 66 can be neatly aligned with the joint between the knitted fabric 66 and the fabric 67.
Since the end loop 66a can be reliably sewn with the main seam 70 in this manner, there is no fear that the end portion of the knitted fabric 66 can be unraveled without being double-folded as in the prior art.
As shown in FIG. 0, the joining portion between the knitted fabric 66 and the cloth 67 can be extremely thin, and can be finished so that there is almost no change in thickness. That is, it is possible to prevent the knitted fabric 66 from rising in an unnecessarily patchy shape as in the related art.
Of course, the stitching between the knitted fabric 66 and the fabric 67 is realized not by chain stitching with a single thread, but by full stitching that connects the upper thread 27 and the lower thread, so that there is no possibility that fine wrinkles are attached to the fabric 67 side. Further, the fixing of the fabric 67 side is performed by the first fabric fixing portion 35.
Since the material 67 is realized by sandwiching the
Therefore, there is no possibility that the fabric 67 is damaged.

When the knitted fabric 66 and the fabric 67 are sewn together, it is advantageous that the distance between the knitted fabric 66 and the fabric 67 is as small as possible because the seam can be tightened. For this reason, in the above description, the locking needle 31 is attached to the front surface of the needle plate 15 instead of the back surface, and the fixing portion 31b of the locking needle 31 is bothersomely buried in the groove 15a on the needle plate surface. Terminal loop
The distance between 66a and the fabric 67 was made as small as possible. Further, the substrate 36 of the first fabric fixing portion 35 is buried on the back surface of the needle plate 15 for the same purpose.

The substrate 36 may be omitted, and the first fabric fixing portion 35 may be directly formed on the back surface of the needle plate 15. Also,
It is not necessarily limited to a method of locking the fabric by locking the lever 42, and for example, a presser plate is hinged rotatably to the back surface of the needle plate 15 via a hinge (not shown),
The presser plate may be configured to be biased toward the needle plate 15 using a leaf spring or a coil spring. When the fabric is fixed to the needle plate 15, the holding plate may be opened against the urging force of the spring, and the edge of the fabric may be sandwiched therebetween.

Further, instead of providing a binder type first fabric fixing portion 35 for bringing the back surface of the substrate 36 or the needle plate 15 into close contact with the pressing plate 37 by the urging force of a spring, for example, FIG.
As shown in the figure, the substrate 71 and the holding plate 72 are hinged openably and closably via a hinge 73, and at least one of the substrate 71 and the holding plate 72 is a strong magnet, and the other is a magnetic material such as iron or nickel. May be used. This utilizes the magnetic force (adsorption force) of the magnet,
Since the cloth is sandwiched between the substrate 71 and the holding plate 72 and fixed to the back surface of the needle plate 15, there is an advantage that the overall shape of the cloth fixing portion can be reduced in thickness. Of course, both the substrate 71 and the holding plate 72 may be formed of magnets having different polarities. Instead of providing the substrate 71, the back surface of the needle plate 15 may be made of a magnet or a magnetic material, and the holding plate 72 may be openably and closably connected via a hinge 73 directly attached to the back surface of the needle plate 15. Good. Further, the hinge 73 may be omitted, and the holding plate 72 may be fixed to the back surface of the needle plate 15 only by the magnetic force of the magnet.

Since the drive system of the sewing machine itself is not the point of the present invention, the simplest hand-operated type is exemplified. However, the upper shaft 63 and the lower shaft 50 may be rotated by an electric motor as well as a foot-operated type. . Further, in the above, the needle bar 17 is adjusted by adjusting the pitch of each gear and the rack portion 34.
The vertical reciprocating motion, the rotary motion of the shuttle 51, and the feeding operation of the needle plate 15 are synchronized.Each operation is realized by a separate stepping motor, and these operations are electronically controlled, so that each operation is controlled. You may comprise so that timing may be adjusted. Further, in the above description, the elongated needle plate 15 extending substantially linearly has been illustrated, but a needle plate formed in an annular shape may be employed. Further, instead of the full-rotation shuttle 51, a half-rotation shuttle may be used to perform the lockstitching process. Of course, in this case, it is necessary to provide an appropriate mechanism for converting the rotation of the lower shaft 50 into a half rotation of the shuttle 51.

Alternatively, as shown in FIG. 12, instead of the shuttle 51, a wedge-shaped looper 87 described in the conventional example may be attached to the tip of the lower shaft 50. The looper 87 applies the sewing thread guided into the first recess 46 by the sewing needle 21 as described above.
While rotating in a certain direction, the loop is formed by grasping with the sword 87a, the loop is held until the sewing needle 21 comes down next, and a chain stitch is formed by passing a sewing thread through the loop. The knit fabric 66 and the fabric 67 are stitched. If the fabric 67 has a certain degree of elasticity, it is more appropriate to use a looper 87 to form an elastic chain-like seam with one thread. The shuttle 51 is attached to the tip of the lower shaft 50.
Is basically the same as the above-described embodiment except that the looper 87 is attached. Therefore, the same reference numerals are given and the description thereof is omitted. However, it is necessary to adjust the timing between the reciprocating vertical movement of the sewing needle 21 and the rotational movement of the looper 87 so that the looper 87 can reliably form a chain stitch.

[0034]

The sewing machine according to the present invention has a needle plate in which a large number of locking needles are arranged in a comb shape.
The stitches of the knitted fabric can be reliably captured, and the terminal loop and the fabric can be reliably stitched. For this reason, not only can the end loop peculiar to the knitted fabric be aligned neatly at the joint between the knitted fabric and the fabric, but there is no worry that the end portion of the knitted fabric can be unraveled without double folding as in the past, The junction between the knitted fabric and the fabric is extremely thin,
It is possible to finish with almost no change in thickness. Further, since the fabric side is fixed by the fabric fixing portion, it is not necessary to pierce the fabric with the locking needle, and the fabric is not damaged during fixing.

If the stitch between the knitted fabric and the fabric is realized by book-stitching that tightly binds the upper thread and the lower thread using a kettle, the seam does not expand or contract, so that the fine side is provided on the fabric side with poor elasticity. Wrinkling can be effectively avoided.
Alternatively, if the stitching of the knitted fabric and the fabric is realized by sewing one sewing thread in a chain shape with a looper, the seam has elasticity, so that it is possible to cope with the sewing with the elastic fabric.

[Brief description of the drawings]

FIG. 1 is a side view showing an overall image of a sewing machine according to the present invention.

FIG. 2 is a partial sectional view showing a tip portion of a bed of the sewing machine.

FIG. 3 is a partial plan view showing the front side of a needle plate of the sewing machine.

FIG. 4 is a partial front view of the locking needle of the needle plate as viewed from the side of a sewing machine main body.

FIG. 5 is a partial plan view showing the back side of the needle plate.

FIG. 6 is an enlarged side view showing a first fabric fixing portion attached to the back surface of the needle plate.

FIG. 7 is a front view showing a flywheel of the sewing machine.

FIG. 8 is a conceptual diagram showing a drive system of the sewing machine.

FIG. 9 is a plan view showing a state in which the knitted fabric and the fabric are stitched by the sewing machine.

FIG. 10 is a side view showing a state where the knitted fabric and the fabric are stitched by the sewing machine.

FIG. 11 is a perspective view showing a second fabric fixing portion attached to the back surface of the needle plate.

FIG. 12 shows an example in which a looper is attached to the tip of a lower shaft.
FIG. 3 is a partial sectional view similar to FIG. 2.

FIG. 13 is a partial front view of a needle plate according to a conventional knitted fabric exclusive sewing machine viewed from a sewing machine main body side.

FIG. 14 is a partial cross-sectional view showing a tip portion of a bed of a conventional knitted fabric exclusive sewing machine.

FIG. 15 is a schematic diagram showing a state in which each terminal loop of a pair of knitted fabrics is pierced into a locking needle of a conventional sewing machine dedicated to knitted fabrics.

FIG. 16 is a side view showing a state where a knitted fabric and a fabric are stitched by a conventional lockstitch sewing machine.

[Explanation of symbols]

 10 Sewing machine 14 Sewing machine body 15 Needle plate 15a Groove of needle plate 21 Sewing needle 27 Needle thread 28 Needle hole 31 Locking needle 31a Locking portion 31b Fixed portion 35 First fabric fixing portion 37 Holding plate 39 Coil spring 51 Hook 66 Knit fabric 66a Knitted fabric end loop 67 Fabric 72 Presser plate 74 Second fabric fixing part 87 Looper 87a Looper blade point

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-160692 (JP, A) JP-A 54-82144 (JP, U) JP-A 54-63034 (JP, U) JP-A 53-82 161055 (JP, U) Actually open 1973-162843 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) D04B 39/08 D05B 7/00 D05B 27/18 D05B 29/08 D05B 73/12

Claims (6)

(57) [Claims] 1. A sewing needle having a needle hole through which an upper thread is passed and arranged reciprocally in a vertical direction, and a lower thread housed in a sword tip and inside, and arranged so as to be capable of full rotation or half rotation. A sewing machine main body provided with a shuttle and a drive mechanism for realizing continuous reciprocating movement of the sewing needle and continuous rotary movement of the shuttle; and a knitted fabric attached to the sewing machine main body and one of the knitted fabrics to be sewn. A needle plate in which a large number of locking needles for piercing stitches are arranged in a comb-tooth shape at a predetermined pitch, and the fabric to be sewn is fixed to the back surface of the needle plate, which is mounted on the back surface of the needle plate. The sewing needle is lowered along the locking needle of the needle plate with the upper thread passed through the needle hole, and penetrates the stitches and the cloth of the knitted fabric and the blade point of the shuttle. After supplying the upper thread to the vicinity, it starts to rise. The lower thread housed inside the sewing machine is tied to the upper thread to form a stitch for lockstitching. The needle plate has a stitch equivalent to one stitch in cooperation with the reciprocating motion of the sewing needle and the rotating motion of the shuttle. A sewing machine, wherein the sewing machine is driven so that the locking needle is fed by one pitch each time it is formed. 2. A sewing needle having a needle hole through which a sewing thread is passed and arranged reciprocally in a vertical direction, a looper having a sword point and arranged rotatably, and a continuous reciprocating movement of the sewing needle. And a drive mechanism for realizing a continuous rotational movement of the looper; and a plurality of locking needles mounted on the sewing machine main body and for piercing a stitch of a knitted fabric to be sewn with a predetermined number. A needle plate arranged in a comb-like shape at a pitch, and cloth fixing means mounted on the back surface of the needle plate and fixing the other cloth to be sewn to the back surface of the needle plate, the sewing needle comprising: With the sewing thread passed through the needle hole, the sewing thread descends along the locking needle of the needle plate, passes through the stitches and the cloth of the knitted fabric, supplies the sewing thread to the vicinity of the sword tip of the looper, and then turns upward. Capture the above sewing thread at the point of the sword through the rotating motion, Forming a loop and forming a chain stitch through the loop through the sewing thread conveyed through the next downward stroke of the sewing needle, wherein the needle plate cooperates with the reciprocating motion of the sewing needle and the rotational motion of the looper. The sewing machine is driven so that the locking needle is fed by one pitch each time a stitch is formed by one stitch. 3. The locking needle has an L-shape including a locking portion that stands upright from the surface of the needle plate and a fixed portion that is disposed parallel to the surface of the needle plate. 3. The sewing machine according to claim 1, wherein the fixing portion is buried in a groove formed on the surface of the needle plate. 4. The dough fixing means comprises a pressing plate disposed on the back side of the needle plate, and urging means for urging the pressing plate toward the back side of the needle plate. The sewing machine according to any one of claims 1 to 3, wherein the sewing machine is fixed between the back side of the plate and the presser plate. 5. The sewing machine according to claim 4, wherein said urging means is a spring. 6. The sewing machine according to claim 4, wherein said urging means is a magnet.