JP2000126489A - Sewing machine part to be in contact with thread or cloth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent rattling, burning, thread cutting, or the like, of whole devices by forming an almost uniform composite plating skin of eutectoid of nickel or a nickel based alloy and fluorine containing compound microparticles on the surface of a sewing machine metallic part. SOLUTION: A rotary shuttle device A as a sewing machine part to be in contact with thread or cloth comprises an inner shuttle 1 and an outer shuttle 2. The inner shuttle 1 is equipped with a rail 11 on the outer periphery face 1a and a storage room 12 and a stud 13 inside. On the whole surfaces of such rotary shuttle device, a composite plating skin of eutectoid of nickel or a nickel based alloy and fluorine containing microparticles is formed. It is also preferable to form the composite plating skin on only the rotation sliding positions of the rotary shuttle device A, i.e., the inner periphery face 2b of the outer shuttle, the outer periphery face 1a and the inner periphery face 1b of the inner shuttle 1, and the outer face 13a of the stud 13. As the nickel based alloy to form eutectoid with fluorine containing compound microparticles, a ternary nickel- phosphorus-tungsten alloy, or the like, is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine component which comes into contact with a thread or a cloth, and more particularly, a sewing machine which has a small wear and frictional resistance at a sliding portion which comes into contact with the thread or a cloth, and has excellent functionality and durability. For parts.

[0002]

2. Description of the Related Art Conventionally, a rotary hook device of a sewing machine for guiding an upper thread and a lower thread is provided with a bobbin case and an outer hook respectively inside and outside of an inner hook which is non-rotatably fitted at a hook stopper of a sewing machine body. Are mounted so as to be relatively rotatable, and at the time of sewing work, the bobbin case and the outer shuttle are slidably driven on the inner and outer peripheral surfaces of the inner shuttle, respectively. Here, the inner kettle and the outer kettle rotate relative to each other by guiding a rail provided on an outer peripheral part of the inner kettle to a rail groove provided on an inner peripheral part of the outer kettle.

[0003]

The sliding parts such as the rotating sliding parts and the guiding parts which come into contact with the thread are liable to be worn out, causing rattling in the whole rotary hook device, increasing noise and increasing sewing accuracy. , The frequency of replacing worn parts increases, and the running cost increases. If the frictional resistance during sliding is large, a strong rotational force acts on the inner hook from the outer hook that is driven to rotate, and engages with the detent recess provided in the inner hook and the detent recess. A strong shearing force is generated between the hook and the hook, and a large resistance force acts on the upper thread passing between the engaging portion and the inner hook and the outer hook. There was also. Furthermore, the rail at the outer periphery of the inner hook and the rail groove at the inner periphery of the outer hook are liable to seize, and there has been a limit in improving the sewing speed.

On the other hand, in a cloth presser for guiding a cloth,
If the coefficient of friction of the sliding surface in contact with the cloth is large, the cloth is sewn in a wrinkled state, causing a problem that sewing deviation occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and reduces the abrasion and frictional resistance of each sliding portion of a metal sewing machine component for guiding a thread or a cloth, thereby reducing the rattling, seizure, Prevents thread breakage, sewing deviation, etc.,
As a result, it is an object of the present invention to provide a sewing machine part which comes into contact with a thread or a cloth which can improve durability and sewing speed.

[0006]

Means for Solving the Problems The present inventor has conducted intensive studies in solving the above-mentioned problems, and as a result, has conducted a composite plating process in which fine particles of fluorine-containing compound are codeposited on nickel or a nickel-based alloy. The present invention has been completed by paying attention to the fact that abrasion and frictional resistance of a sliding portion are significantly reduced by applying to a surface of a metal sewing machine part that comes into contact with the metal sewing machine.

That is, according to the present invention, a composite plating film is formed on a surface of a metal sewing machine component, in which fine particles of a fluorine-containing compound are substantially uniformly co-deposited with nickel or a nickel-based alloy. A component for a sewing machine which comes into contact with a thread or cloth provided with frictional properties was constructed. The surface on which the composite plating film has been formed has high surface hardness and heat resistance of nickel or a nickel-based alloy, corrosion resistance, and features such as lubricity and non-adhesion of fluorine-containing compounds, low friction,
Even if the sewing speed is increased, rattling, baking, thread breakage, sewing deviation, etc. do not occur, and a metal sewing machine part excellent in functionality and durability as a whole can be obtained.

[0008] Here, a composite plating film formed on a surface of a ternary alloy of nickel-phosphorus-tungsten or a ternary alloy of nickel-boron-tungsten by co-eutecting fluorine-containing compound fine particles substantially uniformly is described. It has high hardness characteristics due to tungsten, and maintains a high surface hardness even when the amount of eutectoid fluorine-containing compound particles is increased.

When polytetrafluoroethylene having excellent dispersibility is used as the fluorine-containing compound, the uniformity of the fine particles of the fluorine-containing compound in the composite plating film is improved, and the lubricity, non-adhesion and low lubricity are reduced. Friction is further improved.

Further, if the eutectoid content of the fluorine-containing compound fine particles in the composite plating film is as large as 18% by volume or more, the lubricating property, non-adhesiveness and low friction property of the surface are improved, and the contact sliding portion is improved. While baking and yarn breakage are reliably prevented, if the amount of eutectoid is too large, the surface hardness decreases, so the amount of eutectoid of the fluorine-containing compound fine particles is 18 to 35.
It is preferred to be volume%.

Preferably, the dynamic friction coefficient of the composite plating film is suppressed to a small value, especially 0.1 or less.
By suppressing to such a low dynamic friction coefficient, thread breakage and sewing deviation are prevented beforehand, and durability and sewing speed are greatly improved. In the present invention, it is sufficiently possible to suppress the dynamic friction coefficient to 0.055. It is possible.

The above-mentioned inner hook in a rotary hook apparatus of a metal sewing machine, comprising an inner pot for accommodating the above-mentioned composite plating film in a rotatable manner with a bobbin case and an outer pot rotatably driven about the inner pot. The one formed on one or both surfaces of the outer hook can prevent backlash due to burning and abrasion, especially at the rotating sliding portion between the inner hook and the outer hook, thereby maintaining sewing accuracy and also preventing thread breakage. You.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in further detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 shows a rotary hook device of a sewing machine as a representative embodiment of a sewing machine component that comes into contact with a thread or a cloth according to the present invention.
Reference numeral 1 denotes an inner pot, and 2 denotes an outer pot. The component for sewing machine that comes into contact with the thread or cloth according to the present invention forms a composite plating film in which nickel or a nickel-based alloy is approximately uniformly co-deposited with fluorine-containing compound fine particles on a metal surface, and forms a contact sliding portion. Abrasion by reducing wear and frictional resistance,
In order to prevent seizure and thread breakage, the rotary hook device A of the present embodiment forms a carburized and quenched steel material, for example, a metal having high mechanical strength such as S15C or an aluminum alloy as a base material. The composite plating film is formed on the entire surface of the inner pot 1 and the outer pot 2 thus formed.

The rotary hook device A includes an inner hook 1 for accommodating a bobbin case (not shown) so as to be rotatable relative to each other, and an outer hook 2 rotatably driven about the inner hook 1. The inner hook 1 has an outer periphery. A substantially ring-shaped rail 11 is provided on the surface 1a, and a storage room 12 for storing a bobbin case therein, and the storage room 1
A stud 13 for rotatably inserting the bobbin case is provided upright at the center of the stud 2. A detent recess 14 is formed in the upper part for guiding the upper thread and engaging with a hook stopper (not shown) provided on the sewing machine main body to regulate the rotation of the inner shuttle 1. The outer shuttle 2 has therein a storage chamber 22 for accommodating the inner shuttle 1 so as to be relatively rotatable, and a rail groove 21 for slidably guiding the rail 11 is provided on an inner peripheral surface 2b. .

A composite plating film is formed on the entire surface of the rotary hook apparatus A by eutecting fine particles of a fluorine-containing compound with nickel or a nickel-based alloy.
The composite plating film is not limited to the one formed on the entire surface of the rotary hook device A. For example, the inner peripheral surface 2b of the outer hook 2 Outer peripheral surface 1a and inner peripheral surface 1b, and outer peripheral surface 13 of stud 13
The embodiment formed only on a is also a preferred embodiment. Also,
There is no need to form the composite plating film on the surfaces of both the inner pot 1 and the outer pot 2, and one of the inner pot 1 and the outer pot 2, particularly the outer peripheral surface 1 a, the inner peripheral surface 1 b and the stud of the inner pot 1. The one formed on the surface including at least the outer peripheral surface 13a of the thirteen is also preferable.

A nickel-cobalt alloy, a nickel-phosphorus alloy, a nickel-boron alloy or the like is preferably used as a nickel-based alloy for eutectoid deposition of the fluorine-containing compound fine particles. The use of a boron-tungsten ternary alloy makes it possible to achieve both a low coefficient of friction and high hardness on the surface of the composite plating film.

Examples of the fluorine-containing compound include graphite fluoride and a fluorine-containing polymer compound having a perfluoroalkyl group or a polyfluoroalkyl group in which all or part of the hydrogen moiety of a hydrocarbon group is substituted with fluorine. It is preferable to use one or more of polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, and tetrafluoroethylene-hexafluoropropylene copolymer among the fluorine-based polymer compounds. In particular, the polytetrafluoroethylene (hereinafter, simply referred to as “PTFE”) is also preferable in that it is easily available. These may be used alone or as a mixture.

In addition, in addition to the above-mentioned fluorine-containing compound, it is preferable that boron nitride as a self-lubricating substance is appropriately dispersed and compounded in the composite plating film. The wear resistance of the plating film can be further improved.

The average particle diameter of the fluorine-containing compound fine particles is not particularly limited, but is 0.2 to 1.0 μm, particularly 0.2 to 1.0 μm.
It is preferably 0.5 μm.

The formation of the composite plating film is performed, for example, by using the above-mentioned fine particles of the fluorine-containing compound in a plating solution for forming the above-mentioned nickel or nickel-based alloy by using a surfactant such as a fluorine-based surfactant, if necessary. Is substantially uniformly dispersed, and the inner pot, the outer pot, and the entire portion to be plated of the bobbin case are immersed in the plating solution, and electroplating or electroless plating is performed.

Specifically, for example, as the above-mentioned electroless plating, after a pre-treatment such as cleaning of a portion to be plated by an ordinary method,
Using a nickel-phosphorus plating bath with the following bath conditions,
A composite plating film in which polytetrafluoroethylene fine particles having an average particle diameter of 0.2 μm are uniformly dispersed in a nickel-phosphorus alloy is formed at a thickness of about 10 μm on the plating portion.

That is, the bath conditions are such that the bath temperature is 88-92.
° C, preferably 90-91 ° C, bath ratio 0.5-1.5.
dm ² / L, preferably substantially 0.8dm ² / L, the nickel concentration 4.6~5.1g / L, preferably 4.9 to
5.0 g / L, pH is 4.8-5.2, preferably 4.9-5.1. Thereby, polytetrafluoroethylene fine particles are eutectoid in the composite plating film in an amount of 18 to 35% by volume. The composite plating film in which a large amount of the fluorine-containing compound is eutectoid has extremely excellent surface lubricity, non-adhesiveness and low friction.

Further, the surface on which the composite plating film is formed is subjected to a heat treatment. The surface subjected to the heat treatment in this way has remarkably improved mechanical strength such as hardness, and has improved wear resistance and durability. 220 ° C or higher from the viewpoint of improving hardness,
The heat treatment is preferably performed at a temperature of 300 ° C. or more.

The composite plating film of the present embodiment satisfies all of the dynamic friction coefficient of 0.1 or less, in particular, extremely low frictional resistance of 0.055 to 0.06, heat resistance at a continuous use limit temperature of 290 ° C., and high hardness. It maintains the dimensional accuracy of each part without abrasion against sliding due to continuous high-speed rotation during sewing, and exhibits excellent durability. The rotary hook device A in which such a composite plating film is formed on each rotary sliding portion does not rattle for a long period of time, reliably prevents baking and thread breakage. Even smooth yarn can be guided smoothly without wear, and thread breakage can be prevented without adhering oil to the yarn, so that there is no defect such as soiling of sewing products with the oil.

In such a rotary hook device A, the sewing operation can be performed at a rotation speed 30 to 40% higher than the conventional one while maintaining the sewing accuracy, and the running cost is about 5%.
About double.

The composite plating film according to the present invention may be, for example, a cloth presser,
Suitable for forming on the surface of all metal sewing parts that come in contact with thread or cloth, such as thread guides, and improve durability and sewing accuracy by suppressing the wear and friction coefficient of each contact sliding part. Let it.

[0027]

According to the sewing machine part of the present invention which comes into contact with the thread or the cloth as described above, rattling, baking, thread breakage, sewing deviation, etc. do not occur even when the sewing speed is increased, and the overall function and performance are improved. A highly durable metal sewing machine component is obtained.

If a composite plating film is formed on the surface of a ternary alloy of nickel-phosphorus-tungsten or a ternary alloy of nickel-boron-tungsten with finely-deposited fluorine-containing compound fine particles on the surface thereof, the fine particles of the fluorine-containing compound fine particles can be formed. High surface hardness can be maintained even when the amount of eutectoid is increased.

When polytetrafluoroethylene is used as the fluorine-containing compound, the uniformity of the fine particles of the fluorine-containing compound in the composite plating film is improved, and the lubricity, non-adhesion and low friction can be further improved.

When the eutectoid content of the fluorine-containing compound fine particles in the composite plating film is 18 to 35% by volume, the lubricity, non-adhesion and low abrasion of the surface can be improved while maintaining the surface hardness, Wear and seizure of the contact portion, thread breakage, sewing deviation, and the like can be reliably prevented.

The dynamic friction coefficient of the composite plating film is 0.055
If it is set to 0.1, thread breakage and sewing deviation can be prevented beforehand, and durability and sewing speed can be greatly improved.

The above-mentioned inner hook in a rotary hook apparatus of a metal sewing machine, comprising an inner pot for accommodating the above-mentioned composite plating film in a rotatable manner with a bobbin case and an outer pot rotatably driven about the inner pot. If it is formed on one or both surfaces of the outer hook, it is possible to avoid rattling due to burning and abrasion, particularly at the rotational sliding portion between the inner hook and the outer hook, thereby maintaining sewing accuracy and preventing yarn breakage.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a typical embodiment of a sewing machine component that comes into contact with a thread or a cloth according to the present invention.

[Explanation of symbols]

 A Rotary shuttle device 1 Inner shuttle 1a Outer peripheral surface 1b Inner peripheral surface 2 Outer shuttle 2b Inner peripheral surface 11 Rail 12 Storage room 13 Stud 13a Outer peripheral surface 14 Detent recess 21 Track groove 22 Storage room

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3B150 AA01 CB26 CD04 CE08 CE24 CE26 DG03 HA12 3J011 AA06 AA20 BA08 DA01 JA01 KA07 MA02 QA17 SB14 SB15 SB20 SC04 SC12 3J104 AA44 AA67 AA73 AA75 AA76 BA53 CA09 CA20 DA05 DA06

Claims (7)

[Claims] 1. A composite plating film formed on a surface of a metal sewing machine component by eutecting nickel or a nickel-based alloy with fluorine-containing compound fine particles substantially uniformly, thereby imparting low abrasion and low friction. Parts for sewing machines that come into contact with a thread or cloth. 2. A sewing machine in contact with a thread or cloth according to claim 1, wherein a composite plating film is formed on the surface of the ternary alloy of nickel-phosphorus-tungsten and the fluorine-containing compound fine particles are co-deposited substantially uniformly. parts. 3. A thread or cloth contacting sewing machine according to claim 1, wherein a composite plating film is formed on the surface of the ternary alloy of nickel-boron-tungsten and the fluorine-containing compound fine particles substantially uniformly co-deposited. parts. 4. The sewing machine component according to claim 1, wherein the fluorine-containing compound is polytetrafluoroethylene. 5. The sewing machine component according to claim 1, wherein the eutectoid content of the fluorine-containing compound fine particles in the composite plating film is 18 to 35% by volume. . 6. The composite plating film having a dynamic friction coefficient of 0.0
A sewing machine part which comes into contact with the thread or cloth according to any one of claims 1 to 5, which satisfies 55 to 0.1. 7. The inner hook in a rotary hook apparatus of a metal sewing machine, wherein the sewing machine component includes an inner hook that houses a bobbin case in a rotatable manner and an outer hook that is driven to rotate about the inner hook. And one or both of the outer pot and the outer pot.
A part for a sewing machine, which comes into contact with the thread or cloth according to any one of the preceding claims.