JP3960563B2 - Full clockwise rotation vertical hook - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a clockwise full-rotation vertical hook (hereinafter referred to as a DP type hook, which is viewed from the front) used in industrial sewing machines, in particular, staggered sewing machines.
[0002]
[Prior art]
As shown in FIG. 1, the DP type hook is fixed to the outer hook 1 by a set screw 5 and the outer hook 1 rotating fully clockwise, the non-rotating inner hook 2, and the outer hook 1. It consists of an inner hook presser 3 for sandwiching and supporting the hook 2 and a back plate 4 fixed to the outer hook 1 with screws 6. In this kettle, as shown in FIG. 1 (3), the needle 7 sticks to the cloth 8, and slightly the needle thread loop 9 that will be formed during passing upwardly taker point 1a of the outer holder 1 is captured When the needle thread loop 9 passes around the hook, the needle thread is intertwined with the lower thread to form a seam.
[0003]
As the back plate 4 of this hook, as described in Japanese Utility Model Publication No. 58-23344, the type shown in FIG. 4 (1) and the needle thread loop in the above type as shown in FIG. 5 (1). A type in which a portion in contact with 9 is excised is known.
[0004]
[Problems to be solved by the invention]
The conventional DP type hook needs to correct the vertical movement of the cloth due to the vertical movement of the needle when sewing a thin and soft cloth, and the timing of the contact of the sword tip 1a with the needle 7 is delayed by adjusting the hook mounting phase. The needle thread loop 9 is enlarged. In this case, as shown in FIGS. 2 (1) and 2 (2), the needle thread loop 9 comes into contact with the back surface of the portion 1b facing the sword tip 1a with the thread entry / exit notch 1e of the outer hook interposed therebetween, as shown in FIG. 3) As shown in (4), the needle 7 is tilted so as to be kinked around the center. Since the front loop 9a on the side captured by the sword tip 1a falls down, the sword tip 1a cannot capture the loop 9a, causing skipping and thread breakage. In FIG. 2 (2), a and b are the directions of rotation of the outer hook 1 and the locus of the needle hole with respect to the hook, respectively.
[0005]
With respect to the back plate 4, the type shown in FIG. 4 (1), as shown in FIGS. 4 (2), (3), and (4), if the back loop 9b becomes too large, the fall due to contact with the back plate 4 is severe. Accordingly, the front loop 9a also falls to the sword tip 1a side, and the sword tip 1a cannot capture the loop 9a, causing skipping or the like. In addition, the type shown in FIG. 5 (1), as shown in FIGS. 5 (2), (3) and (4), the back loop 9b does not come into contact with the back plate 4, so it is difficult to fall down, but a thread with strong twist back is used In this case, as shown by a dotted line in FIG. 5 (2) and as shown in FIGS. 5 (5) and (6), the front loop 9a may fall in a direction away from the sword tip 1a. Cause.
[0006]
An object of the present invention is to prevent skipping or thread breakage even when a needle thread loop is formed large in a clockwise full rotation vertical shuttle or when a thread with strong twisting back is used. .
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the clockwise full rotation vertical hook of the present invention has the outer peripheral edge of the needle thread loop formation range of the portion facing the sword tip across the thread entry / exit notch portion in the outer hook to maintain the race portion. The projecting portion is cut away leaving a necessary portion, and further, a protruding portion that contacts the needle thread back loop is formed at a position on the back plate immediately before the sword tip of the outer hook captures the needle thread loop.
[0008]
[Action]
In the clockwise full rotation vertical hook configured as described above, the needle thread loop does not contact the edge of the outer hook by using the outer hook, even when the needle thread loop is large. It is formed without any interruption. Also, by using the back plate, just before the sword tip captures the needle thread loop, the back loop comes into contact with the protrusion and falls in the direction of rotation of the hook, and accordingly, the front loop falls to the sword tip side. Capturing the front loop is facilitated.
[0009]
【Example】
With reference to FIG. 3 and FIG. 6 to FIG. 10, an embodiment of the clockwise fully rotating vertical shuttle of the present invention will be described.
[0010]
This clockwise full-rotation vertical hook is basically the same as a conventional clockwise full-rotation vertical hook, and is between the outer hook 1 that rotates fully clockwise, the non-rotating inner hook 2, and the outer hook 1. The inner hook presser 3 is fixed to the outer hook 1 so as to sandwich the inner hook 2 therebetween, and the back plate 4 is fixed to the outer hook 1.
[0011]
As shown in FIG. 3, the outer hook 1 has a portion 1b facing the sword tip 1a with the thread entry / exit notch 1e interposed therebetween, leaving a wall thickness necessary to maintain the race portion 1c into which the inner hook is fitted. Cut along line 1d. The cut portion indicated by the oblique lines is a portion where the needle thread loop 9 in the case of large formation conventionally contacts.
[0012]
The angle θ from the sword tip 1a to the end of the cut portion is 40 to 90 °. This is the range in which the needle thread front loop 9a can come into contact with the edge of the outer hook.
[0013]
When the outer hook 1 having such a cut portion is used, even when the timing of the contact of the sword tip 1a with the needle 7 is delayed and the needle thread loop 9 is enlarged, the needle thread as shown in FIGS. 3 (3) and (4). Since the loop 9 and the edge of the outer hook 1 do not contact, the needle thread loop 9 can swell without being disturbed at all.
[0014]
Further, when performing staggered stitching using such an outer hook 1, the needle swings like 7a to 7b. However, as described above, the needle thread loop 9 can be enlarged. The needle amplitude can be set wider than before.
[0015]
The back plate 4 is fixed so that a portion centered on the position of the sword tip 1a forms a predetermined distance from the outer hook 1 (see FIG. 1 (1)), and as shown in FIG. It has a needle guard 4a that prevents it from going to the 1a side, and also serves as an upper thread presser that prevents the thread from escaping to the back side of the hook when the sword tip 1a catches the needle thread loop 9. I'm in charge.
[0016]
The back plate 4 employed in this embodiment is of the type shown in FIG. 5 (1) in which the outer peripheral edge (needle thread loop contact portion) at a position where the needle receiver 4a is located is cut out. Further, as shown in FIGS. 6 and 7, the back plate 4 is formed with a protruding portion 4b that contacts the needle thread back loop 9b immediately before the sword tip 1a captures the needle thread loop.
[0017]
When the back plate 4 having such a protrusion 4b is used, as shown in FIG. 7, the back loop 9b swells without being disturbed until it comes into contact with the protrusion 4b. Immediately before capturing, the back loop 9b comes into contact with the protrusion 4b and is tilted in the direction of rotation of the hook. Accordingly, the front loop 9a falls to the sword tip 1a side. In this way, the front loop 9a falls to the sword tip 1a side immediately before the needle thread loop 9 is captured, so that the capture of the front loop 9a by the sword tip 1a is facilitated. The same applies to the case where a yarn with strong twisting back that tends to fall in the direction in which the front loop 9a moves away from the sword tip 1a is used.
[0018]
Incidentally, in the type shown in FIG. 4, it is not certain at which stage the back loop 9b contacts the back plate 4 and the contact time with the back plate 4 is long. When the sword tip 1a comes to the loop capture position, it is no longer possible to capture the loop. On the other hand, in the present invention, the front loop 9a falls at a certain timing, that is, immediately before the sword tip 1a catches the needle thread loop 9, the tip loops toward the sword tip 1a, and the front loop 9a and the sword tip 1a approach each other. The amount by which the front loop 9a falls is stable and no skipping occurs.
[0019]
In addition, as shown in FIG. 8, if the protrusion part 4b protrudes a little to the sword tip 1a side, a contact with the back loop 9b will become still more reliable, and a bigger effect can be acquired.
[0020]
Also in the back plate 4 of the type shown in FIG. 4 (1) described above, as shown in FIG. 9, the outer periphery of the position where the needle receiver 4a is located is bent back so as to be away from the needle 8, and the back loop 9b If the protrusion 4b is formed from the upper edge front part toward the needle 8 direction, the same effect can be obtained.
[0021]
In any case, instead of integrally forming the protruding portion 4b on the back plate 4, as shown in FIG. 10, another component 7 provided with a protruding portion 7a corresponding to the protruding portion 4b is fixed to the back plate 4. You can also. In that case, of course, the same effect can be obtained.
[0022]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0023]
That is, when using an outer hook with the outer peripheral edge cut off, even if the needle thread loop is set large, the needle thread loop will not fall down due to the contact of the outer peripheral edge of the outer hook, so there will be no skipping or thread breakage. . In addition, when the shuttle is used for a staggered sewing machine, the maximum needle amplitude can be set wider than before.
[0024]
When using a back plate with protrusions, the front loop approaches the sword tip just before the sword catches regardless of the size, so even if the thread used is a strong twist back thread, Is stable, and skipping and thread breakage do not occur. Further, when the protrusion is extended in the direction of the sword, it also functions as a needle receiver when the needle is raised.
[Brief description of the drawings]
FIG. 1 is a view of a conventional DP hook, (1) is a side view, (2) is a front view, and (3) is a rear view of a single outer hook.
FIGS. 2A and 2B are views for explaining the operation of an outer pot of a conventional DP hook, wherein FIG. 2A is a side view, FIG. 2B is a rear view, FIG. 3B is a perspective view, and FIG.
3 is a view of the DP hook of the present invention, (1) is a front view of the outer hook, (2) is a cross-sectional view showing the cutting position of the outer hook, (3) is a side view, and (4) is the back surface. FIG.
FIGS. 4A and 4B are diagrams related to a conventional DP hook provided with a back plate having a needle thread loop contact portion, where FIG. 4A is a rear view of the back plate, FIG. 4B is a perspective view of the hook, and FIG. The side view which shows the contact state of a back loop and a back board, (4) is the same top view.
FIGS. 5A and 5B are diagrams relating to an outer pot of a conventional DP hook provided with a back plate from which a needle thread loop contact portion has been cut away; FIG. 5A is a rear view of the back plate, FIG. 5B is a perspective view of the hook; ) Is a side view showing the relationship between a needle thread back loop and a back plate when a normal thread is used, (4) is a plan view thereof, and (5) is a needle thread back loop and back when a thread with strong twisting is used. The side view which shows the relationship with a board, (6) is the same top view.
6A and 6B are views of a back plate in the DP hook according to the present invention, in which FIG. 6A is a side view, FIG. 6B is a back view, and FIG.
FIGS. 7A and 7B are diagrams for explaining the action sequence of the back plate in the DP hook according to the present invention, wherein FIG. 7A is a perspective view, and FIG.
FIG. 8 is a view of another back plate in the DP hook of the present invention, (1) is a side view, (2) is a back view, and (3) is a plan view.
9 is a view of still another back plate in the DP hook according to the present invention, (1) is a side view, (2) is a back view, and (3) is a plan view. FIG. FIG.
FIG. 10 is a view of another back plate in the DP hook of the present invention, (1) is a side view, and (2) is a back view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Outer hook 1a Knife tip 1b The part 1c facing a sword tip Race part 4 Back plate 4a Needle holder 4b Projection part 7 Needle 9 Needle thread loop 9a Needle thread table loop 9b Needle thread back loop

Claims (2)

An outer pot that has a sword tip and fully rotates,
An inner pot in which the bobbin and bobbin case are set,
An inner hook presser fixed to the front side of the outer hook and holding the inner hook so as to be rotatable relative to the outer hook, and a clockwise full-rotation vertical hook whose needle descends on the back side of the outer hook,
The outer peripheral edge of the needle thread loop formed range taker point and face each other across the yarn and out notches of the outer holder is clockwise full rotation perpendicular, characterized in that the resected leaving a part necessary for the maintenance of the race portion Kettle. An outer pot that has a sword tip and fully rotates,
An inner pot in which the bobbin and bobbin case are set,
An inner hook presser fixed to the front side of the outer hook and holding the inner hook so as to be rotatable relative to the outer hook;
A back plate fixed at a predetermined interval on the back side of the outer hook, and a clockwise full turn vertical hook in which the needle descends on the back side of the outer hook,
A clockwise full-rotation vertical shuttle characterized in that a protrusion that contacts the needle thread back loop is formed at a position on the back plate immediately before the sword tip captures the needle thread loop.

Images