JP4054993B2 - Needle feed sewing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a needle feed sewing machine capable of feeding a work cloth by cooperation of a sewing needle and a feed dog.
[0002]
[Prior art]
In general, in order to reliably prevent defective work feed of a work cloth when sewing a relatively thick work cloth such as jeans, the sewing needle is swung in synchronization with the feed dog while the work needle is inserted into the work cloth. A needle feed sewing machine configured to assist cloth feed by a feed dog is known.
[0003]
For example, the applicant of the present application has already proposed the following needle feed sewing machine (see, for example, Patent Document 1). The needle feed sewing machine includes an upper shaft that is rotatably supported in a sewing machine arm, a needle bar base that is supported to swing back and forth in the cloth feed direction, and a needle that is supported by the needle bar base so as to be movable up and down. And a pulley supported on the right end of the upper shaft and a pulley supported on the right end of the lower shaft are connected by a timing belt to connect the upper shaft to the lower shaft rotatably supported in the sewing machine bed. The rotational driving force of the rotationally driven sewing machine motor is transmitted to the lower shaft via the timing belt.
[0004]
The needle feed sewing machine further includes a horizontal feed shaft linked to the lower shaft, a feed dog linked to the lower shaft and the horizontal feed shaft, and a needle bar base connected to the horizontal feed shaft in the cloth feed direction. The horizontal feed shaft and the needle bar swing shaft are interlocked and connected via a swing lever member and a link member disposed on the left side of the timing belt. During cloth feed by the feed dog, the horizontal feed shaft swings in conjunction with the lower shaft. At this time, the needle bar swing shaft connected to the horizontal feed shaft also swings via the link member. Since the needle bar base swings in the cloth feeding direction, the work cloth is fed by the cooperation of the sewing needle and the feed dog.
[0005]
[Patent Document 1]
Japanese Patent No. 2682346 (page 3-5, FIG. 1)
[0006]
[Problems to be solved by the invention]
In the needle feed sewing machine described in Patent Document 1, the swing lever member that interlocks and connects the horizontal feed shaft and the needle bar swing shaft is disposed on the left side of the timing belt. The width in the left-right direction of the sewing machine becomes large, and the sewing machine becomes large. Furthermore, since the space between the sewing needle mounted on the needle bar and the pedestal portion is narrowed, the roller is narrowed and workability is deteriorated.
[0007]
An object of the present invention is to reduce the size of the needle feed sewing machine by disposing a swing lever member that connects the horizontal feed shaft and the needle bar swing shaft in an empty space in the needle feed sewing machine. For example, widening and improving workability.
[0008]
[Means for Solving the Problems]
The needle feed sewing machine according to claim 1 is supported by an upper shaft that is rotatably supported in the sewing machine arm, a needle bar base that is swingably supported in the cloth feed direction, and a needle bar base that is movable up and down. A needle bar that moves up and down in conjunction with the upper shaft, a lower shaft that is rotatably supported in a sewing machine bed, a rotating body that is supported by the upper shaft, and a rotating body that is supported by the lower shaft. A rotation transmission connecting body that is stretched and connects these two rotating bodies, a horizontal feed shaft that is linked to the lower shaft, and a feed that is linked to the lower shaft and the horizontal feed shaft to perform a four-feed motion. A tooth bar, a needle bar swinging shaft connected to the horizontal feed shaft to swing the needle bar base in the cloth feed direction, and an interlocking mechanism for interlockingly connecting the horizontal feed shaft and the needle bar swinging shaft. In the needle feed sewing machine, the interlocking mechanism is connected to the needle bar swinging shaft and swingable in the cloth feed direction. And a connecting link member for interlockingly connecting the swing lever member and the horizontal feed shaft, and the swing lever member is disposed inside the rotation transmission connecting body. .
[0009]
At the time of cloth feed by this needle feed sewing machine, the horizontal feed shaft swings in conjunction with the lower shaft to which the rotational driving force is transmitted from the upper shaft via the two rotary bodies and the rotation transmission coupling body, and is processed by the feed dog. The cloth is fed in the cloth feeding direction. At the same time, the swing motion of the horizontal feed shaft is transmitted to the swing lever member via the connecting link member, the swing lever member swings in the cloth feed direction, and the needle bar swing shaft also swings. Since the needle bar swings in the cloth feed direction, the cloth feed by the feed dog is assisted by the sewing needle attached to the needle bar. Here, the swing lever member is disposed in a space inside the rotation transmission coupling body, which is an empty space in the needle feed sewing machine.
[0010]
According to a second aspect of the present invention, in the needle feed sewing machine according to the first aspect of the invention, the rotation transmission coupling body is a timing belt. Therefore, a swing lever member is disposed inside the timing belt.
[0011]
A needle feed sewing machine according to a third aspect is the needle feeding sewing machine according to the first or second aspect, wherein the connecting link member is located on a sewing head side with respect to the rotation transmission connecting body. Therefore, the connecting link member is connected to the swing lever member from the sewing head side.
[0012]
According to a fourth aspect of the present invention, there is provided the needle feed sewing machine according to the first or second aspect, wherein the connecting link member is located on the opposite side of the sewing head with respect to the rotation transmission connecting body. Accordingly, the connecting link member is connected to the swing lever member from the side opposite to the sewing head.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described. This embodiment is an example in which the present invention is applied to a lockstitch needle feed sewing machine.
[0014]
As shown in FIG. 1, the lock stitch feed sewing machine M includes a sewing machine bed 10, a leg column 11 that extends upward from the right end of the sewing bed 10, and an upper end of the leg column 11 to the sewing machine bed 10. The sewing machine arm 12 includes a sewing machine arm 12 that extends to the left so as to face each other and has a sewing head 13 at the left end. In the sewing machine arm 12, an upper shaft 15 extending in the left-right direction is rotatably supported in the sewing machine arm 12, and a needle bar vertical movement mechanism 20 and a balance vertical movement mechanism are provided.
[0015]
Since the balance vertical movement mechanism has the same configuration as that of a normal sewing machine, the description thereof will be omitted, and the needle bar vertical movement mechanism 20 will be briefly described. First, a needle bar 21 having a sewing needle N attached to the lower end is supported by a needle bar base 22 extending in the vertical direction so as to be movable up and down. The needle bar base 22 is fixed in the sewing machine head 13 at the upper end. The support shaft 23 is supported so as to be able to swing back and forth. On the other hand, a hand pulley 37 (see FIGS. 2 and 3) is provided at the right end portion of the upper shaft 15, and a needle bar crank 24 is fixed to the left end portion of the upper shaft 15, and the connecting rod 25 is connected to the needle bar crank 24. An upper end portion is pivotally attached, and a lower end portion of the connecting rod 25 is connected to a center portion in the height direction of the needle bar 21 via a needle bar holder 26. Accordingly, since the needle bar crank 24 is rotated by the rotation of the upper shaft 15, the needle bar 21 is reciprocated up and down via the connecting rod 25 and the needle bar holder 26. Further, the sewing machine arm 12 is provided with a needle bar swinging shaft 42 which is connected to a horizontal feed shaft 32 which will be described later and swings the needle bar base 22 in the cloth feeding direction in parallel to the upper shaft 15. A proximal end portion of a needle bar swinging arm 44 is fixed to the left end portion of the needle bar swinging shaft 42, and a tip end portion of the needle bar swinging arm 44 is an upper and lower formed on the lower end portion of the needle bar base 22. It is slidably engaged with the engaging groove 22a in the direction.
[0016]
A timing pulley (corresponding to a rotating body) 27 that rotatably supports a lower shaft 16 extending in the left-right direction is fixed to the right end of the lower shaft 16 and rotates integrally with the lower shaft 16 in the sewing machine bed 10. And a timing pulley (corresponding to a rotation transmission connecting member) 29 is stretched over a timing pulley (corresponding to a rotating member) 28 fixed to the right end of the upper shaft 15 and rotating integrally with the upper shaft 15. It is built. Therefore, when the upper shaft 15 is rotationally driven by a rotational drive of a sewing machine motor (not shown), the lower shaft 16 is also rotationally driven via the timing belt 29 at the same time.
[0017]
A disc-shaped eccentric ring 34 is fixed to the lower shaft 16, and the rear end portion of the horizontal feed linkage 30 is rotatably fitted on the eccentric ring 34, and the front end portion of the horizontal feed linkage 30 has a corner. A piece (not shown) is rotatably attached, and the square piece is slidably fitted in a groove of a switcher (not shown). Note that these square pieces and switching units are well known and will not be described. A lower end portion of the horizontal feed link 31 is also fixed to the square piece, and an upper end portion of the horizontal feed link 31 is rotatably connected to a horizontal feed arm 33 fixed to a horizontal feed shaft 32 extending in the left-right direction. . Accordingly, since the front end of the horizontal feed linkage 30 swings in the front-rear direction via the eccentric ring 34 due to the rotational drive of the lower shaft 16, the horizontal feed shaft 32 is moved via the horizontal feed link 31 and the horizontal feed arm 33. Swing. Here, at the left end portion of the lower shaft 16, a feed dog vertical movement mechanism for moving the feed dog up and down (not shown) is connected, and at the left end portion of the horizontal feed shaft 32, the feed dog front and rear moves the feed dog back and forth. The moving mechanism is connected.
[0018]
Next, an interlocking mechanism 35 that interlocks and connects the horizontal feed shaft 32 and the needle bar swing shaft 42 will be described. As shown in FIGS. 1 to 3, the interlock mechanism 35 is configured to cause the needle bar 21 to swing in the front-rear direction by timing the feed dog forward and backward, and is attached to the right end portion of the needle bar swinging shaft 42. A swing lever member 43 that is connected and swingable in the cloth feed direction (front-rear direction), and a connecting link member 39 that interlocks and connects the swing lever member 43 and the horizontal feed shaft 32 are provided.
[0019]
The upper end portion of the vertically extending swing lever member 43 is fixed to the right end portion of the needle bar swing shaft 42. Furthermore, the rear end portion of the connecting link member 39 is connected to the lower end portion of the swing lever member 43 so as to be rotatable from the left side. By the way, a needle bar swinging crank 36 is fixed to the right end portion of the horizontal feed shaft 32 and is connected to the right end portion of the needle bar swinging crank 36 at a position eccentric from the axis of the horizontal feed shaft 32 and extending in the front-rear direction. The link member 39 is pivotally supported so as to be rotatable.
[0020]
Therefore, when the horizontal feed shaft 32 swings in conjunction with the lower shaft, the connecting link member 39 and the swing lever member 43 connected to a position eccentric from the axis of the horizontal feed shaft 32 swings in synchronization therewith. Further, the swinging motion of the swing lever member 43 is transmitted to the needle bar swing arm 44 via the needle bar swing shaft 42, the needle bar base 22 swings, and the needle bar 21 swings back and forth. Move.
[0021]
By the way, the swing angle of the swing lever member 43 when the needle bar 21 swings back and forth in this way is a slight angle (for example, about 2 degrees). Therefore, a large space is not required in the front-rear direction in order to arrange the swing lever member 43 in the pedestal 11. Therefore, as shown in FIGS. 1 to 3, in this needle feed sewing machine M, the swing lever member 43 is disposed inside the timing belt 29 stretched over the two timing pulleys 27 and 28. The vacant space in the pedestal 11 is effectively used. In addition, the swing lever member 43 and the timing belt 29 are always separated from each other in the front-rear direction. The connecting link member 39 connected to the swing lever member 43 is located on the left side (sewing head 13 side) of the timing belt 29.
[0022]
The operation and effect of the needle feed sewing machine M described above will be described.
At the time of cloth feeding, the feed dog linked to the lower shaft 16 and the horizontal feed shaft 32 performs four feed movements. At this time, the horizontal feed is synchronized with the swinging movement of the horizontal feed shaft 32 linked to the lower shaft 16. The connecting link member 39 and the swing lever member 43 that are connected to a position eccentric from the axis of the shaft 32 swing. Then, the swing motion of the swing lever member 43 is transmitted to the needle bar swing arm 44 through the needle bar swing shaft 42, the needle bar base 22 swings, and the needle bar 21 swings back and forth. Then, the work cloth is fed in the front-rear direction by the four-feed movement of the feed dog and the sewing needle N swinging back and forth.
[0023]
Here, the swing lever member 43 is disposed inside the timing belt 29 that is stretched over the two timing pulleys 27 and 28, and an empty space in the pedestal 11 is effectively used. Therefore, the left and right widths of the pedestal 11 are reduced, and the size of the needle feed sewing machine M can be reduced. In addition, since the space between the sewing needle N and the left side surface of the pedestal 11 (so-called “ft roller”) can be widened, workability is improved.
[0024]
By disposing the swing lever member 43 on the inner side of the timing belt 29, the width of the leg post 11 in the left-right direction (the axial direction of the upper shaft 15 and the lower shaft 16) is reduced. However, if the length of the needle feed sewing machine M in the left-right direction is shortened by moving the pedestal 11 toward the needle bar 21 without widening the bottom roller, the upper shaft 15 and the lower shaft 16 may be increased. The needle feed sewing machine M can be reduced in size and weight. Furthermore, it is of course possible to slightly widen the roller and slightly shorten the length of the needle feed sewing machine M in the left-right direction.
[0025]
Next, modified embodiments in which various modifications are made to the embodiment will be described. However, the same reference numerals are given to those having the same configuration as in the above embodiment, and the description thereof is omitted as appropriate.
[0026]
1] As shown in FIG. 4, in the pedestal 11A, the connecting link member 39 is connected to the lower end of the swing lever member 43 disposed inside the timing belt 29 from the right side. The timing belt 29 may be positioned on the right side (opposite the sewing head 13). Even in this case, since the left and right widths of the pillar portion 11A are reduced, the size of the needle feed sewing machine M can be reduced. In addition, since the space between the sewing needle N on the sewing machine head 13 side and the pedestal 11A can be made wider than in the above-described embodiment, the foot roller becomes wider and the workability is further improved.
[0027]
2] The rotation transmission coupling body for transmitting the rotation of the upper shaft 15 to the lower shaft 16 is not limited to the timing belt 29 of the above embodiment, but a chain or other member formed in a loop shape is used. May be.
[0028]
【The invention's effect】
According to the first aspect of the present invention, the swing lever member is disposed in the space inside the rotation transmission coupling body, and the size of the needle feed sewing machine is reduced by effectively utilizing the space in the needle feed sewing machine. Can do. In addition, when the swing lever member is disposed in the pedestal portion, the width of the pedestal portion is reduced to widen the space between the sewing needle attached to the needle bar and the pedestal portion, that is, the roller. Thus, it is possible to improve workability and / or to reduce the size of the entire needle feed sewing machine.
[0029]
According to the second aspect of the present invention, since the swing lever member is disposed inside the timing belt, it is possible to reduce the size of the needle feed sewing machine by effectively utilizing the empty space inside the timing belt.
[0030]
According to the invention of claim 3, since the connecting link member is located on the sewing head side with respect to the rotation transmission connecting member, the connecting link member is disposed on the inside of the rotation transmitting connecting member. The member can be connected from the sewing head side.
[0031]
According to the fourth aspect of the present invention, since the connecting link member is located on the opposite side of the sewing machine head with respect to the rotation transmission connecting body, the connecting link member is disposed on the inner side of the rotation transmission connecting body. The moving lever member can be connected from the side opposite to the sewing head.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of an internal mechanism of a needle feed sewing machine according to an embodiment of the present invention.
FIG. 2 is a front view of an essential part of an internal mechanism of a pedestal portion.
FIG. 3 is a side view of an essential part of an internal mechanism of a pedestal part.
FIG. 4 is a schematic perspective view of an internal mechanism of a modified needle feed sewing machine.
[Explanation of symbols]
M Needle feed sewing machine 10 Sewing machine bed 11 Leg column 12 Sewing arm 13 Sewing head 15 Upper shaft 16 Lower shaft 21 Needle bar 22 Needle bar bases 27 and 28 Timing pulley 29 Timing belt 32 Horizontal feed shaft 35 Interlocking mechanism 39 Connecting lever member 42 Needle bar swing shaft 43 Swing lever member

Claims (4)

An upper shaft that is rotatably supported in the sewing machine arm, a needle bar base that is swingably supported in the cloth feed direction, and a vertical movement that is supported by the needle bar base so as to move up and down and interlocks with the upper shaft. A needle bar, a lower shaft rotatably supported in the sewing machine bed, a rotating body supported by the upper shaft, and a rotating body supported by the lower shaft. A rotation transmission coupling body that couples the body, a horizontal feed shaft that is linked to the lower shaft, a feed dog that is linked and linked to the lower shaft and the horizontal feed shaft, and a feed dog that is linked to the horizontal feed shaft. In a needle feed sewing machine comprising a needle bar swing shaft for swinging the needle bar base in the cloth feed direction, and an interlocking mechanism for interlockingly connecting the horizontal feed shaft and the needle bar swing shaft,
The interlocking mechanism is
A swing lever member connected to the needle bar swing shaft and swingable in the cloth feed direction;
A connecting link member for interlockingly connecting the swing lever member and the horizontal feed shaft;
The needle feed sewing machine, wherein the swing lever member is disposed inside the rotation transmission coupling body. The needle feed sewing machine according to claim 1, wherein the rotation transmission coupling body is a timing belt. 3. The needle feed sewing machine according to claim 1, wherein the connecting link member is positioned on a sewing head side with respect to the rotation transmission connecting body. 3. The needle feed sewing machine according to claim 1, wherein the connection link member is located on a side opposite to a sewing head with respect to the rotation transmission connection body.

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