JP4420418B2 - Sewing machine vertical full rotary hook - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vertical full rotary hook of a sewing machine, and more particularly to an oilless hook whose inner hook outer race portion is made of synthetic resin.
[0002]
[Prior art]
1 and 2, a conventional vertical rotating rotary hook 1 of a sewing machine includes a steel outer hook 2 that rotates in conjunction with the main shaft of the sewing machine, and an inner hook that is rotatably supported by the outer hook. 3 and an inner hook stopper 4 which is fixed to the sewing machine frame so as to be adjustable and prevents rotation of the inner hook. An inner hook race portion 5 formed on the outer periphery of the inner hook is loosely fitted in the outer hook race groove to support the inner hook 3 so as to be rotatable.
[0003]
As shown in FIG. 2, the inner hook 3 is fixed to an outer peripheral portion 6 a formed at the bottom of the inner hook body 6 by adhering a resin-made race portion 5 with a part of the ring cut off. The notch portion 7 of the inner hook race, in which a part of the annular ring is cut, has one end portion thereof as a yarn dividing portion 5a and the other end portion thereof as a yarn removal portion 5b.
[0004]
As the outer hook 2 rotates, the inner hook 3 also rotates, but the inner hook stopper 4 prevents the rotation. At this time, as shown in FIG. 1, the abutting portions of the inner hook 3 and the inner hook stopper 4 are in surface contact, and the hook rotation center O is positioned on the substantially extended line. For this reason, only the tangential force F <b> 1 acts on the inner hook stopper 4 with respect to the rotation of the inner hook 3. Further, only a tangential force acts on the inner hook 3 as a reaction force. Further, when the inner hook 3 is locked to the inner hook stopper, the inner hook race notch 7 is positioned above the inner hook rotation center O. Further, the inner hook race cutout portion 7 is arranged substantially symmetrically with respect to the vertical movement locus of the needle 8.
[0005]
In order to reduce sliding resistance in accordance with the non-lubrication of the hook, the inner hook race portion 5 or the entire inner hook 3 is made of a synthetic resin such as liquid crystal polymer, high-density polyethylene, and polyimide.
[0006]
In the inner hook 9 of the counterclockwise vertical full rotary hook shown in FIG. 3, an annular resin race portion 11 is fitted and fixed in a groove 10 a formed from the center portion of the inner hook main body 10. The inner race part 11 has a notch 12 formed in a part of the outer periphery. The one end is a yarn dividing portion 11a, and the other end is a yarn removal portion 11b.
[0007]
A clockwise full rotary hook is used for staggered stitches, and a counterclockwise vertical full rotary hook is used for main stitches.
[0008]
[Problems to be solved by the invention]
However, in the case of a conventional full vertical rotary hook of a sewing machine, particularly an oil-free type hook whose inner hook outer race portion is made of synthetic resin, the inner hook outer race portions 5 and 11 are worn or damaged when used for a long time.
[0009]
The wear, breakage, etc. of the outer peripheral race portion of the inner hook mainly progresses and occurs at the yarn dividing portions 5a and 11a and the yarn dropout portions 5b and 11b. When the thread drop portions 7b and 10b that receive the upper thread loop from the outer hook sword tip are worn or damaged, and the upper thread loop is not captured, the upper thread loop is moved between the inner hook and the outer hook. The thread breakage occurs.
[0010]
The present invention has been made to solve the above-mentioned problems, and suppresses the wear of the inner hook outer race part, in particular, suppresses the wear of the inner hook outer race thread drop-out part, the thread separation part, or breaks. It is an object of the present invention to provide a vertical rotating rotary hook for a sewing machine that prevents the above.
[0011]
[Means for Solving the Problems]
In order to solve the above problem, the invention according to claim 1
An inner hook (3, 9) having at least an outer peripheral race portion formed of a synthetic resin;
When the inner hook race portion has a raceway that is loosely fitted together, and the outer rotary hook (2) that rotates in conjunction with the main shaft,
An inner hook stopper (4) fixed to a sewing machine frame and preventing rotation of the inner hook;
The rotational torque of the outer hook is transmitted to the inner hook,
When the inner hook is locked to the inner hook stopper, in the vertical full rotation hook of the sewing machine in which the inner hook race notch (7, 12) is positioned above the inner hook rotation center,
At least one of the abutment portion (h) between the inner hook and the inner hook stopper is inclined or rounded, and the rotation transmitted to the inner hook when the inner hook is locked to the inner hook stopper. A vertical full-rotation shuttle of a sewing machine , wherein torque generates a component force (F2) in the vertical direction toward the inner hook.
[0012]
According to the first aspect of the invention, the inner hook 3 also rotates as the outer hook 2 rotates, but the inner hook stopper 4 prevents the rotation. At this time, since a component force (F2) is generated in the inner hook 3 vertically downward, both ends of the inner hook race notch portion (the thread separating portion, the thread removing portion) located above the inner hook rotation center (O). ) Is less likely to contact the outer hook race groove. For this reason, the wear of the inner hook outer periphery lace thread dropout portion and the yarn separation portion is suppressed, and the inner hook outer periphery race yarn dropout portion and the yarn separation portion are prevented from being damaged. As a result, the durability of the hook is improved.
[0013]
The invention according to claim 2 is the vertical full rotary hook of the sewing machine according to claim 1,
The vertical full rotary hook of the sewing machine is a clockwise vertical full rotary hook (1) having an inner hook race portion at the bottom of the inner hook.
[0014]
According to the second aspect of the present invention, the clockwise full rotation rotary hook having the inner hook race portion at the inner hook bottom portion is easy to peel off and has a structure that is weak against impact. More improved.
[0015]
The invention described in claim 3 is a vertical full rotary hook of the sewing machine according to claims 1 and 2,
One of the contact portions of the inner hook and the inner hook stopper is 5 ° to 30 ° in a direction opposite to the hook rotation direction with respect to a straight line (Y) connecting the rotation center of the hook and the hook contact portion. It was set as the structure which is an inclined surface.
[0016]
According to the third aspect of the present invention, it is possible to provide a vertical full-rotary shuttle of a sewing machine that is less expensive and improves the durability of the shuttle.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
First, a first embodiment of the present invention will be described with reference to FIG.
The first embodiment relates to a clockwise vertical full rotary hook, and those described above are denoted by the same reference numerals and description thereof is omitted. FIG. 4A is an overall view of the shuttle, and FIG. 4B is a detailed view of the contact portion h.
[0018]
The middle hook side contact surface 3a of the first embodiment is an inclined surface formed in a direction opposite to the hook rotation direction r.
The inclination angle θ is θ = the straight direction Y connecting the hook rotation center O and the contact portion P between the hook 3 and the hook stopper 4, and θ = It is preferable to form in the range of 5 ° to 30 °.
An abutment surface 4a for retaining the inner hook abutment surface 3a is positioned on a straight line Y.
[0019]
The operation of the first embodiment will be described.
As the outer hook 2 rotates in the r direction, the rotational torque of the outer hook 2 is transmitted to the inner hook 3 through the outer hook race groove and the inner hook race portion 5. The inner hook 3 rotates, but the inner hook stopper 4 prevents the rotation. At this time, the inner hook side contact surface 3a is an inclined surface as described above. For this reason, when the inner hook 3 is pressed (locked) against the inner hook stopper 4, a component force F <b> 2 that is pressed toward the rotation center O of the hook is generated.
[0020]
As described with reference to FIGS. 1 and 3, when the inner hook 3 is locked to the inner hook stopper 4, both ends of the inner hook race cut-out portion (the thread separating portion 10a and the thread removal portion 10b) are rotated by the inner hook. Located above the center O.
[0021]
Then, the inner hook 3 is pressed downward by the component force F2, and both end portions of the inner hook race cut-out portion (thread separating portion 10a, thread removal portion 10b) are less likely to come into contact with the outer hook race groove. For this reason, wear at both end portions (thread separation portion, thread removal portion) of the inner hook race cutout portion is suppressed, and breakage is prevented. As a result, the durability of the hook is remarkably improved, and the collision sound between the inner hook and the outer hook is reduced.
[0022]
Next, a modification of the first embodiment will be described with reference to FIGS. Similar to the first embodiment, this modification coincides with the fact that the inner hook 3 is directed vertically downward and a component force F2 to be pressed is generated, and the contact surface between the inner hook 3 and the inner hook stopper 4 is the same. The shape of h is different. For this reason, only the shape of the different contact surface h will be described, and the others will be omitted.
[0023]
In FIG. 5, instead of forming an inclined surface on the contact surface 3a on the inner hook 3 side of the first embodiment in order to generate the component force F2, an inclined surface 4a is formed on the contact surface 4a on the inner hook stopper side. It is the modification which formed. The inclination angle, direction, and the like of this inclined surface are preferably in the range of 5 ° to 30 ° in the direction opposite to the hook rotation direction r, as in the first embodiment.
[0024]
FIG. 6 shows a modified example in which inclined surfaces are formed on both the inner hook side contact surface 3a and the inner hook stop side contact surface 4a in a direction opposite to the hook rotation direction r. For example, the contact surface 4a is inclined 10 ° and the contact surface 3a is inclined 30 ° with respect to a straight line (not shown) passing through the contact point of the contact portion and the shuttle rotation center.
[0025]
FIG. 7 shows a modification in which both the inner hook side contact surface 3a and the inner hook stop side contact surface 4a are formed in an R shape. In this case, the inclination angle θ of the tangent line X of R is based on a straight line Y connecting the rotation center O of the hook and the contact portion P between the hook 3 and the hook stop 4 as in the first embodiment. Thus, it is preferable to form in the range of the inclination of θ = 5 ° to 30 ° in the direction opposite to the hook rotation direction r.
[0026]
FIG. 8 shows an embodiment in which the present invention is applied to the counterclockwise vertical full rotary hook 15. Since the rotation direction s of the hook is reversed, the direction of the inclined surface of the abutting portion h and the direction of the tangential direction of R are different from those of the first embodiment and the modifications thereof, but are the same.
[0027]
FIG. 8B shows the inner hook 13a provided with an inclined surface. (C) is an inner hook stopper 14a provided with an inclined surface. (D) is provided with inclined surfaces having different angles on both the inner hook 13a and the inner hook stopper 14a. For example, the inclination angle of the inner hook stopper 14a is 10 ° and the inclination angle of the inner hook is 15 °. Is. (E) makes both contact surfaces into a round shape. Then, as described above, the component force F2 is generated vertically downward on the inner hook 13 to suppress wear at both ends of the inner hook race notch, to prevent breakage, and to suppress the occurrence of hook collision noise. To do.
[0028]
The present invention can be variously modified without being limited to the above embodiment.
For example, in the present embodiment, it is formed by one abutting surface formed on a straight line passing through the shuttle rotation center and an inclined surface that is inclined at a predetermined angle with respect to this one abutting surface. It is easily conceivable to form an inclined surface inclined at a predetermined angle and an r-shaped contact surface that contacts the inclined surface.
[0029]
【The invention's effect】
According to the first aspect of the invention, the inner hook 3 also rotates as the outer hook 2 rotates, but the inner hook stopper 4 prevents the rotation. At this time, since a component force (F2) is generated in the inner hook 3 vertically downward, both ends of the inner hook race notch portion (the thread separating portion, the thread removing portion) located above the inner hook rotation center (O). ) Is less likely to contact the outer hook race groove. For this reason, the wear of the inner hook outer periphery lace thread dropout portion and the yarn separation portion is suppressed, and the inner hook outer periphery race yarn dropout portion and the yarn separation portion are prevented from being damaged. As a result, the durability of the hook is improved. Further, the hook collision noise is suppressed.
[0030]
According to the second aspect of the present invention, the clockwise full rotation rotary hook having the inner hook race portion at the inner hook bottom portion is easy to peel off and has a structure that is weak against impact. More improved.
[0031]
According to the third aspect of the present invention, it is possible to provide a vertical full-rotary shuttle of a sewing machine that is less expensive and improves the durability of the shuttle.
[Brief description of the drawings]
[Fig. 1] Illustration of a conventional clockwise full rotary hook [Fig. 2] Inner hook of a conventional clockwise vertical rotary hook [Fig. 3] Inner hook of a conventional counterclockwise vertical full rotary hook [Fig. 4] FIG. 5 is a diagram illustrating a modification of the first embodiment. FIG. 6 is a modification of the first embodiment. FIG. 7 is a modification of the first embodiment. Application example [Explanation of symbols]
3. · Inner hook 9 ·· Inner hook 2 ·· Outer hook 4 ·· Inner hook stopper 7 ·· Inner hook race notch 12 ·· Inner hook race notch 1 ·· clockwise vertical full turn hook ··· Junction

Claims (3)

At least the outer race portion of the inner pot formed of synthetic resin,
Both this inner hook race portion has a raceway that is loosely fitted, and the outer holder that rotates in conjunction with the main shaft,
An inner hook stopper fixed to a sewing machine frame and preventing rotation of the inner hook;
The rotational torque of the outer hook is transmitted to the inner hook,
When the inner hook is locked to the inner hook stopper, in the vertical full rotation hook of the sewing machine in which the inner hook race notch is located above the inner hook rotation center,
At least one of the abutment portions of the inner hook and the inner hook stopper is inclined or R-shaped, and when the inner hook is locked to the inner hook stopper, the rotational torque transmitted to the inner hook is A vertical full-rotation shuttle for a sewing machine, wherein a component force is generated vertically downward on the inner shuttle. In the vertical full rotary hook of the sewing machine according to claim 1,
The vertical full rotation rotary hook of the sewing machine is characterized in that the vertical full rotary hook of the sewing machine is a clockwise vertical full rotary hook having an inner hook race part at the bottom of the inner hook. In the vertical full rotary hook of the sewing machine according to claim 1,
One of the contact portions of the inner hook and the inner hook stopper is an inclined surface of 5 ° to 30 ° in a direction opposite to the rotation direction of the hook with respect to a straight line connecting the rotation center of the hook and the contact portion. Sewing machine vertical full-rotary shuttle.

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