JP3992819B2 - sewing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sewing machine provided with a cushioning material for determining a bottom dead center of a presser foot support bar.
[0002]
[Prior art]
In the conventional sewing machine, as shown in FIG. 7, the needle bar 42 is supported in a needle bar guide hole 45 a provided in the needle bar guide part 45 of the sewing machine head body 40 so as to be movable up and down. The presser foot support bar 44 is supported by the support bar guide groove 46 provided in the upper and lower sides so as to be movable up and down. An engagement fitting 47 is fixed to the upper end of the needle bar 42, and a holding portion 48 provided at the front of the fitting 47 holds the upper end of the presser foot support bar 44 so as to be relatively movable up and down. I have it. On the other hand, a coupling fitting 49 is fixed to the center portion of the presser foot support bar 44, and the center portion of the needle bar 42 is inserted into a hole 50 provided in the rear portion of the fitting 49 so as to be relatively movable up and down. . Thus, the needle bar 42 and the presser foot support bar 44 are coupled so as to be relatively movable up and down.
[0003]
A pressing spring 51 having a strong resilience is interposed between the engagement metal fitting 47 and the coupling metal 49, and when the needle bar 42 is lowered, the coupling metal 49 and the presser foot are supported via the depression spring 51. The rod 44 is pushed down to descend. An O-ring 52 as a cushioning material is attached to the peripheral wall of the needle bar 42 between the upper surface of the needle bar guide part 45 of the sewing machine head body 40 and the coupling fitting 49, and the O-ring 52 serves as a locking part 49a. The bottom dead center of the presser foot support bar 44 is determined by the contact of the lower edge of the hole 50 of the joint fitting 49.
[0004]
The sewing machine configured as described above operates as follows. First, when the needle bar 42 is lowered by the needle bar hitting 53 that is driven up and down by a driving means (not shown), the coupling fitting 49, the presser foot support bar 44, and the presser foot 43 are pushed down via the presser spring 51. It is done. When the locking portion 49a of the coupling fitting 49 comes into contact with the O-ring 52 (bottom dead center position indicated by a two-dot chain line in FIG. 7), the lowering of the presser foot 43 stops. Thereafter, only the needle bar 42 is further lowered and penetrates the work cloth W. At this time, the pressing spring 51 is compressed between the engagement fitting 47 and the coupling fitting 49 as the needle bar 42 is lowered, so that the repulsive force is applied to the O-ring 52. When the needle bar 42 reaches its bottom dead center position, the needle bar 42 starts to rise, but the cloth presser 43 biased downward by the pressing spring 51 stops at the bottom dead center position and presses the work cloth W. Yes. Then, after the needle 41 is removed from the work cloth W, the presser foot 43 and the presser foot support bar 44 are also raised together with the needle 41 and the needle bar 42.
[0005]
[Problems to be solved by the invention]
However, when the coupling fitting 49 fixed to the presser foot support bar 44 is lowered and the locking portion 49a comes into contact with the O-ring, an impact force is applied to the O-ring 52. Further, when the presser foot support bar 44 reaches the bottom dead center and the needle bar 42 is further lowered, a compressive force is applied to the O-ring 52. For this reason, the O-ring 52 as a cushioning material may be damaged or cut. In this case, the needle bar 42 must be once removed from the sewing machine head body 1 and the O-ring 52 must be reattached. The problem that it takes is occurring.
[0006]
In particular, the sewing machine that sews the processed cloth W of thick material (thick cloth, hard cloth, leather, etc.) uses the pressing spring 51 that has a particularly strong resilience. There are many cases. The reason why the pressing spring 51 having a strong resilience is used is that the needle 41 is difficult to be removed from the durable work cloth W. Therefore, when the resilience of the pressing spring 51 is weak, the needle bar 42 is dead. This is because the cloth presser 43 cannot fully press the work cloth W when it rises from the point position, and the needle 41 and the cloth presser 43 rise while the needle 41 is stuck in the work cloth W.
[0007]
The object of the present invention is to solve the above-mentioned problems, and even if a thick work cloth as well as a thin work cloth is sewn, the cushioning material that determines the bottom dead center of the work clamp support rod is hardly damaged, and maintenance thereof is also possible. The object is to provide an easy sewing machine.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the sewing machine according to the present invention includes a plurality of needle bars and a plurality of cloth presser support bars arranged in parallel so that they can be moved up and down, and the needle bar that descends the presser foot support bar via a pressing spring. when depressing the, in the sewing machine that is configured to determine the bottom dead center of the fabric presser support rod by the locking portion provided on said fabric presser support rod abuts against the cushioning material, the plurality of the cushioning material Each of the plurality of locking portions of the presser foot support bar is formed in a single longitudinal block shape that can contact, and the cushioning material is formed in an inverted L-shaped cross section so that the vertical portion of the inverted L-shape is formed. It is characterized by being mounted in a groove provided in the needle bar guide .
[0009]
In the sewing machine of the present invention, a plurality of needle bars and a plurality of cloth presser support bars are juxtaposed in a vertically movable manner, and when the descending needle bar pushes down the cloth presser support bars via a pressing spring, In a sewing machine configured to determine a bottom dead center of the presser foot support bar by a locking portion provided on the presser foot support bar coming into contact with the buffer material, the buffer material is attached to the plurality of presser foot support bars. Each of the plurality of locking portions is formed into a plurality of divided blocks that can contact each other, and each cushioning material is formed in an inverted L shape in cross section, and the vertical portion of the inverted L shape is provided in the needle bar guide portion. It is characterized by being mounted in a groove and abutting the cushioning material (6) .
[0010]
The buffer material is not particularly limited as long as the impact force can be reduced, and examples thereof include a resin material such as urethane resin and a rubber material such as chloroprene (CR) rubber.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a sewing machine embodying the present invention will be described with reference to FIGS. A needle bar guide portion 2 formed in a plane arc shape is provided on the front surface of the sewing machine head body 1 of the sewing machine. A plurality of needle bar guide holes 2a are arranged in the needle bar guide part 2 at regular intervals, and the needle bar 3 is inserted into each of the needle bar guide holes 2a so as to be movable up and down. A needle 4 is attached to the lower end of the needle bar 3 by a needle stopper 22 and a screw 23, and a needle plate 20 having a needle hole 21 is provided below the needle 4. At the upper end of the needle bar 3, there is provided an engagement fitting 13 with which a needle bar hitting 7 driven up and down by a driving means (not shown) is engaged. Then, the needle bar 3 to be driven up and down during the sewing process is moved in an arc so as to successively come to the front center of the sewing machine head body 1, and the needle bar hitting 7 is engaged with the engagement fitting 13 of the needle bar 3, so that the needle bar 3 is raised and lowered.
[0012]
A plurality of support bar guide grooves 8 are juxtaposed in front of each needle bar guide hole 2a of the needle bar guide part 2 with a predetermined interval, and each of the support bar guide grooves 8 has a presser foot. The support bar 9 is supported so as to be movable up and down. The coupling fitting 15 is fixed to the substantially center portion of the presser foot support bar 9 with a fixing screw 27, and the fixing position can be adjusted up and down. A hole 16 is provided in the rear part of the coupling fitting 15, and the center part of the needle bar 3 is inserted into the hole 16 so as to be relatively movable up and down. A rearward end portion of the coupling metal 15 is provided with a protruding locking portion 15a toward the rear, and the locking portion 15a comes into contact with the cushioning material 6 when the presser foot support bar 9 is lowered, thereby pressing the presser foot. The bottom dead center of the support bar 9 is determined. Further, the upper end portion of the presser foot support bar 9 is held by a holding portion 14 provided at the front portion of the engagement fitting 13 so as to be relatively movable up and down.
[0013]
A presser foot 10 is attached to the lower end of the presser foot support bar 9. The lower part of the needle bar 3 is inserted into the needle bar insertion hole 11 in the upper part of the presser foot 10 so as to be relatively movable up and down, and the needle 4 can be inserted into the through hole 12 in the lower part of the presser foot 10. Yes.
[0014]
A pressing spring 17 having a strong elasticity is interposed between the engagement fitting 13 of the needle bar 3 and the coupling fitting 15 fixed to the presser foot support bar 9, so that the needle bar hitting 7 is connected to the needle bar 3. Is lowered, the presser foot support bar 9 is pushed down via the presser spring 17. Further, a push-up spring 18 having a weak elasticity is interposed between the coupling fitting 15 and the sewing machine head body 1.
[0015]
The buffer material 6 is a longitudinal urethane resin block material formed in a curved shape as shown in FIG. 5, and its cross section is formed in an inverted L shape. The cushioning material 6 is mounted in a curved groove 25 provided at a distance on the rear side of the needle bar guide portion 2 along the plurality of needle bar guide holes 2 a of the needle bar guide portion 2. The lower surface of the engaging portion 15a of the fitting 15 is brought into contact with the outer peripheral wall side edge portion 6a of the upper surface of the cushioning material 6 when the presser foot support rod 9 is lowered.
[0016]
The sewing machine configured as described above operates as follows. First, when the needle bar 3 is lowered by the needle bar hitting 7 driven up and down by a driving means (not shown) from the state shown in FIG. 2, the presser foot support bar 9 and the presser foot are pressed via the pressing spring 17. 10 is pushed down and descends. As shown by the solid line in FIG. 3, when the locking portion 15 a of the coupling metal 15 abuts against the cushioning material 6, the lowering of the presser foot support bar 9 and the presser foot 10 stops. Thereafter, as indicated by a two-dot chain line in FIG. 3, only the needle bar 3 is further lowered, and the needle 4 penetrates the work cloth W. At this time, as the needle bar 3 is lowered, the pressing spring 17 is compressed between the engagement fitting 13 of the needle bar 3 and the coupling fitting 15 secured to the presser foot support bar 9, so that the repulsive force is a buffer material. 6 will be joined. When the needle bar 3 reaches the bottom dead center position, the needle bar 3 starts to rise, but the presser foot 10 urged downward by the pressing spring 17 having a strong resilience stops at the bottom dead center position and is a work cloth. W is pressed. Then, after the needle 4 comes out of the work cloth W, the presser foot support bar 9 and the presser foot 10 together with the needle bar 3 and the needle 4 are also raised.
[0017]
According to the sewing machine configured as described above, since the shock-absorbing material 6 is formed in a block shape, the pressing spring 17 having a strong resilience that can handle not only the thin work cloth W but also the thick work cloth W. Even if used, unlike conventional O-rings, it will not be damaged or cut.
[0018]
Further, since the buffer material 6 is formed in a non-ring shape, for example, when replacing the buffer material 6 that has deteriorated over time, unlike the conventional case, the buffer material 6 that has deteriorated can be removed without removing the needle bar 3 and replaced with a new one. Things can be worn. Therefore, maintenance work can be easily performed.
[0019]
In addition, this invention is not limited to the structure of the said embodiment, For example, as follows, it can also be changed and embodied suitably in the range which does not deviate from the meaning of invention.
(1) As shown in FIG. 6, the cushioning material 6 is divided and provided for each needle bar 3. In this way, the cushioning material 6 can be exchanged for each needle bar 3.
(2) A locking portion that comes into contact with the cushioning material 6 is provided in another part of the coupling metal 15 or other than the coupling metal 15.
[0020]
(3) A plurality of needle bar guide holes 2a are linearly provided in the front surface of the sewing machine head main body 1 at regular intervals, and the needle bar 3 to be driven up and down at the time of sewing is successively provided at the front center of the sewing machine head main body 1. Applying the present invention to a type of sewing machine that is linearly moved to come. For example, in the case of the first embodiment, the cushioning material 6 is a longitudinal block material formed linearly along the plurality of needle bar guide holes 2a.
[0021]
【The invention's effect】
As described in detail above, according to the sewing machine according to the first aspect of the present invention, there is provided a cushioning material that determines the bottom dead center of the presser foot support rod even when a thin work cloth as well as a thin work cloth is sewn. There is an excellent effect that it is difficult to damage.
[Brief description of the drawings]
FIG. 1 is a perspective view of a sewing machine according to an embodiment of the present invention as viewed from the front side.
FIG. 2 is a side sectional view showing the sewing machine.
FIG. 3 is a side sectional view showing another state of the sewing machine.
4 is a cross-sectional view taken along line IV-IV in FIG.
FIG. 5 is a perspective view showing a buffer material of the sewing machine.
FIG. 6 is a view similar to FIG. 4 showing a modification example of the sewing machine.
FIG. 7 is a side sectional view showing a conventional sewing machine.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sewing machine head body 3 Needle bar 6 Cushioning material 9 Work clamp support bar 15a Locking part 17 Press spring

Claims (1)

  A plurality of needle bars (3) and a plurality of cloth presser support bars (9) are juxtaposed so as to be able to move up and down, and the needle bar (3) that descends moves through the presser spring (17) to the cloth presser support bars (9 ) Is pressed down, the locking part (15a) provided on the presser foot support bar (9) comes into contact with the cushioning material (6) to determine the bottom dead center of the presser foot support bar (9). In the sewing machine configured as described above, the cushioning material (6) is formed in one longitudinal block shape in which any of the plurality of locking portions (15a) of the plurality of presser foot support bars (9) can abut. The sewing machine is characterized in that the cushioning material (6) is formed in an inverted L-shaped cross section, and the vertical portion of the inverted L-shape is mounted in a groove (25) provided in the needle bar guide portion (2).

Images