JP4083890B2 - Sewing needle bar - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a needle bar of a sewing machine in which a sewing needle is attached to a predetermined position of an insertion hole.
[0002]
[Prior art]
A conventional needle bar of a sewing machine will be described with reference to FIG.
FIG. 4 shows an exploded perspective view of a needle bar of a conventional sewing machine and its peripheral members.
The needle bar 101 is connected to a needle bar drive mechanism (not shown) above and moves up and down when the sewing machine is driven. An insertion hole 101a is formed at the lower end of the needle bar 101 at a predetermined depth, and the lower side surface penetrates from the outer periphery to the insertion hole 101a in a direction perpendicular to the axial direction of the needle bar 101 in order to screw the fixing screw 104. A fixing screw hole 101b is formed.
[0003]
A thread guide 102 is attached below the needle bar 101. The thread guide 102 is partly cut and formed in an annular shape having an inner circumference that is slightly smaller than the outer circumference of the needle bar 101, and a through hole 102a that penetrates from the outer circumference to the inner circumference is formed at the center and at the lower end. A guide portion 102b through which the needle thread passes is formed. Further, since the thread guide 102 is formed of a metal having plasticity, the inner periphery thereof can be expanded according to the size of the outer periphery of the needle bar 101.
[0004]
The insertion hole 101a of the needle bar 101 is formed so that the sewing needle 103 can be inserted therethrough. Above the sewing needle 103, a cylindrical handle portion 103a having an outer periphery slightly smaller than the inner periphery of the insertion hole 101a is formed so as to be inserted into the needle bar 101, and a needle thread is inserted below the sewing needle 103. Thread hole 103b is formed penetrating left and right. On one side of the opening of the thread hole 103b, a concave hole 103c is formed so that the hook tip (FIG. 5) can pass therethrough, and on the other side, a long groove 103d is formed in the longitudinal direction of the sewing needle 103. It is formed to extend in the direction.
[0005]
When assembling the above components, first, the thread guide 102 is fitted under the needle bar 101 while utilizing its elastic force, so that the fixing screw hole 101b and the through hole 102a are matched. Next, the handle 103a of the sewing needle 103 is inserted all the way into the insertion hole 101a and rotated so that the hook tip 105 (FIG. 5) passes through the punch 103c. When the position is determined, the fixing screw 104 is passed through the through hole 102a. The sewing needle 103 is fixed to the needle bar 101 by being screwed into the fixing screw hole 101b.
[0006]
When replacing the sewing needle, loosen the fixing screw 104, take out the sewing needle 103 from the insertion hole 101a of the needle bar 101, and then insert the new sewing needle 103 into the insertion hole 101a and tighten the fixing screw 104. To complete the sewing needle replacement.
[0007]
[Problems to be solved by the invention]
However, because the size of the inner periphery of the insertion hole 101a of the needle bar 101 varies depending on the manufacturer, the size of the sewing needle 103 (the size of the sewing needle), etc. Since it is designed to be larger than the outer periphery of the handle portion of any sewing needle, there is a backlash between the insertion hole 101 a of the needle bar 101 and the handle portion 103 a of the sewing needle 103.
[0008]
Accordingly, as shown in FIG. 6, when the sewing needle is attached to the needle bar, if the tip of the sewing needle 103 is pressed and attached to the right, the needle is tilted in the direction indicated by the solid line in the figure and leftward. There is a possibility that the sewing needle may be attached at various inclinations depending on the attachment method, such as inclining in the direction indicated by the chain line in the figure when attached by pressing.
Therefore, when the sewing needle 103 is replaced, if there is a difference in the inclination of the sewing needle 103 before and after the replacement due to a difference in the attachment method, as shown in FIG. Since the distance changes, the distance between the sewing needle 103 and the sword tip 105 of the hook must be adjusted again to an appropriate distance so that the sword tip 105 scoops the needle thread, which makes it difficult to replace the sewing needle. was there.
[0009]
In particular, in a so-called staggered sewing machine that forms a zigzag seam by swinging the sewing needle to the left and right as shown in FIG. 7, when the sewing needle 103 is in the left position, the timing at which the sewing needle 103 and the sword tip 105 intersect. Since when the amount of ascending from the lowest point of the sewing needle 103 is small compared to the case where the sewing needle 103 is in the middle position, only a small loop is formed. It is necessary to make the distance from the sewing needle as small as possible. Specifically, the distance between the sword tip and the sewing needle is 0.04 mm to 0.1 mm for a lockstitch sewing machine or the like, whereas it is a very small distance of 0 to 0.05 mm for a staggered sewing machine. . Accordingly, the adjustment of the distance between the sewing needle and the hook tip of the hook in the staggered sewing machine is particularly troublesome work that requires skill, and performing this every time the sewing needle is replaced is a heavy burden on the operator. It was.
[0010]
Further, when attaching the needle bar 101 of the sewing needle 103, the direction of the sewing needle 103 is visually confirmed and attached to the needle bar 101.
Specifically, in the case of FIG. 5, the hook has a rotation shaft in the left-right direction on the paper surface, and the sword tip 105 rotates about this rotation shaft, so that the needle hole 103 b of the sewing needle 103 is the rotation shaft of the hook. It is visually positioned and attached so that the bore 103c is on the sword tip 105 side and the long groove 103d is on the opposite side of the sword tip 105.
[0011]
However, since the sewing needle 103 is thin and the needle hole 103b is small, there is a problem that the direction of the sewing needle is difficult to understand for the elderly and the like, and the attaching operation of the sewing needle is troublesome.
SUMMARY OF THE INVENTION An object of the present invention is to provide a needle bar for a sewing machine that can easily replace or attach a sewing needle.
[0012]
[Means for Solving the Invention]
The invention described in claim 1
A needle bar having an insertion hole formed along the axial direction;
A sewing needle having a long groove formed along the vertical direction;
A fixing screw for fixing a handle portion of the sewing needle inserted into the insertion hole of the needle bar to the needle bar;
In a needle bar of a sewing machine provided with a thread guide mounted on the outer periphery of the lower end of the needle bar,
A mounting hole formed at a predetermined position on the outer periphery of the needle bar along a direction orthogonal to the needle bar axis direction;
An attachment groove formed in the needle bar so as to reach the lower end of the needle bar from the attachment hole;
One end side is attached to the attachment hole of the needle bar, and the other end side engages with the long groove of the sewing needle, and includes a positioning member having a spring property,
While the positioning member is housed in the mounting groove, the sewing needle is positioned so that the other end side of the positioning member engages with the long groove of the sewing needle after the sewing needle is inserted into the insertion hole of the needle bar. Then, the positioning member is configured to press the handle portion of the sewing needle to a predetermined position of the insertion hole of the needle bar.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an exploded perspective view of the needle bar of the sewing machine of the present invention and its peripheral parts. FIG. 2 is an assembled view of FIG. 3 is a schematic side sectional view of FIG.
In the drawings for explaining the present invention, the same components as those in the prior art are denoted by the same reference numerals, and detailed description thereof is omitted.
[0018]
The needle bar of the sewing machine of the present invention also supports the sewing needle below the same as the needle bar of the conventional sewing machine, and moves up and down by driving the sewing machine to cooperate with a well-known hook mechanism disposed below the needle bar. Operation, that is, the hook point of the hook passes through the stitch of the sewing needle, and the needle thread is scooped to form a desired seam. Further, the positional relationship between the needle bar and the shuttle is nothing different from the conventional one.
[0019]
In the needle bar 101, a mounting hole 1 is formed from the outer periphery to the insertion hole 101a in the direction orthogonal to the axial direction of the needle bar 101 to the vicinity of the insertion hole 101a. A mounting groove 2 having a depth shallower than that of the mounting hole 1 is formed below the mounting hole 1 to the lower end of the needle bar 101 along the axial direction of the needle bar 101.
The formation positions of the attachment hole 1 and the attachment groove 2 in the circumferential direction are such that when the direction of the sewing needle 103 is in an appropriate direction so as to form a seam, The position is such that the long groove 103d is aligned on the same straight line.
[0020]
Reference numeral 3 denotes a positioning member, which is formed of a desired elastic member made of a substantially U-shaped wire. The base end 3a is inserted into the mounting hole 1 and is bent into an L shape from the base end 3a. The body 3b is inserted into the groove 2 and the tip 3c is bent from the body 3b toward the sewing needle 103. The positioning member 3 is formed on the same plane as the long groove 103d, the mounting hole 1 and the mounting groove 2 when the sewing needle 103 is in an appropriate direction, and the distal end portion 3c is engaged with the long groove 103d. The engaging portion 3c1 is engaged with the long groove 103d only when the portion 3c1 is formed and the sewing needle 103 is in an appropriate direction.
[0021]
Next, the effect | action by such a structure is demonstrated below.
The base end portion 3 a of the positioning member 3 is inserted into the mounting hole 1 of the needle bar 101 and the body portion 3 b is inserted into the mounting groove 2. In this state, the positioning member 3 is prevented from coming out of the mounting hole 1 and the mounting groove 2 by fitting the thread guide 102 below the needle bar 101 using its elastic force. In the state before the sewing needle 103 is attached, the positioning member 3 has its engaging portion 3c1 reaching the right side of the long groove 103d as shown by a chain line in FIG.
[0022]
The sewing needle 103 is attached to the needle bar 101 by engaging the engaging portion 3c1 of the positioning member 3 in the long groove 103d of the sewing needle 103 and resisting the elastic force of the positioning member 3 in FIG. Moving to the left, the handle 103a is inserted into the insertion hole 101a of the needle bar 101.
Then, the thread guide 102 is rotated to match the through hole 102a with the fixing screw hole 101b of the needle bar 101, and the fixing screw 104 is screwed through the through hole 102a to fix the sewing needle 103 to the needle bar 101.
[0023]
In the present invention, the engaging portion 3c1 engages with the long groove 103d when the sewing needle 103 is in an appropriate direction . For this reason, only by engaging the long groove 103d with the engaging portion 3c1, the direction of the sewing needle 103 is positioned in an appropriate direction that can form a seam .
When the sewing needle 103 is attached, the positioning member 3 is elastically deformed by the sewing needle 103 as shown by a solid line in FIG. The elastic deformation of the positioning member 3 presses the sewing needle 103, and the sewing needle 103 rotates counterclockwise in FIG. 3 with the point at the lower end of the insertion hole 101a as a fulcrum . However, the upper end of the handle 103a of the sewing needle 103 comes into contact with the left surface of the needle bar insertion hole 101a, and the sewing needle 103 is positioned.
After the sewing needle 103 is inserted into the insertion hole 101a , the sewing needle 103 is positioned so that the long groove 103d of the sewing needle engages with the engaging portion 3c1 of the positioning member 3. When the needle guide 102 is attached to the lower end of the needle bar, the sewing needle 103 can be positioned at substantially the same inclination by the pressing force of the positioning member 3 . Further, even when the sewing needle 103 is replaced, it can be reproduced so that the distance between the sewing needle 103 and the hook point 105 of the hook is almost the same.
[0024]
Here, since the mounting direction of the fixing screw 104 is the front and back direction in FIG. 3 which is substantially orthogonal to the mounting hole 1, the sewing needle 103 is fixed while being positioned even when the fixing screw 104 is screwed. It will be.
The present invention is not limited to the above embodiment, and may be modified without departing from the spirit of the present invention.
[0025]
[Second Embodiment]
FIG. 8 shows a second embodiment. FIG. 8 is a schematic side sectional view of the needle bar and its surroundings according to the second embodiment.
In the second embodiment, the sewing needle is positioned at a predetermined position by a magnet.
[0026]
A magnet 10 is embedded and fixed in an embedded hole 11 that penetrates from the outer periphery to the insertion hole 101a in a direction orthogonal to the axial direction of the needle bar 101.
As a result, the handle 103a of the sewing needle 103 inserted into the insertion hole 101a is attracted to the magnet 10 and is brought into close contact with the side surface of the insertion hole 101a for positioning.
[0027]
Therefore, since the sewing needle 103 is always positioned at a desired position, even when the sewing needle is replaced, the distance between the sewing needle and the hook sword tip does not change before and after the replacement, and the same state is always reproduced. it can.
Here, since the mounting direction of the fixing screw 104 is the front and back direction in FIG. 8 which is substantially orthogonal to the embedding hole 11, the sewing needle 103 is fixed while being positioned even when the fixing screw 104 is screwed. It will be.
[0028]
As described above, the sewing machine needle bar of the present invention is substantially same mounting since the shank of the needle is configured to include a positioning member for positioning to a desired position of the insertion hole of the needle bar, the needle Since the reproducibility of attaching to the position can be provided, it is not necessary to adjust the distance between the sewing needle and the sword tip of the hook after changing the sewing needle, and the sewing needle replacement work can be simplified.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a needle bar and its peripheral members of a sewing machine according to the present invention.
FIG. 2 is an assembled view of the needle bar of the sewing machine of the present invention and its peripheral members.
FIG. 3 is a schematic side sectional view of the needle bar of the sewing machine of the present invention and its periphery.
FIG. 4 is an exploded perspective view of a conventional needle bar of a sewing machine and its peripheral members.
FIG. 5 is a schematic side view of a conventional needle bar of a sewing machine and its periphery.
FIG. 6 is a diagram for explaining a difference in inclination depending on how the sewing needle is attached.
FIG. 7 is a partial schematic explanatory view of a staggered sewing machine.
FIG. 8 is a schematic side sectional view of a second embodiment.
[Explanation of symbols]
1 ··· Mounting hole 2 ··· Mounting groove 3 ··· Positioning member 3a ··· Base end 3b ··· Body 3c ··· · · · Tip 3c1 ············································ Needle bar 102 ·································································· 104 ········ Fixing screw 105 ················

Claims (1)

A needle bar having an insertion hole formed along the axial direction;
A sewing needle having a long groove formed along the vertical direction;
A fixing screw for fixing a handle portion of the sewing needle inserted into the insertion hole of the needle bar to the needle bar;
In a needle bar of a sewing machine provided with a thread guide mounted on the outer periphery of the lower end of the needle bar,
A mounting hole formed at a predetermined position on the outer periphery of the needle bar along a direction orthogonal to the needle bar axis direction;
An attachment groove formed in the needle bar so as to reach the lower end of the needle bar from the attachment hole;
One end side is attached to the attachment hole of the needle bar, the other end side is engaged with the long groove of the sewing needle, and includes a positioning member having a spring property,
While the positioning member is housed in the mounting groove, the sewing needle is positioned so that the other end side of the positioning member engages with the long groove of the sewing needle after the sewing needle is inserted into the insertion hole of the needle bar. Then, the positioning member presses the handle portion of the sewing needle to a predetermined position of the insertion hole of the needle bar.

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