JP2781818B2 - Manufacturing method of suture needle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a suture needle used for suturing a living tissue.

<Related Art> A suture needle used for a surgical operation or a suture needle used for a dental treatment includes a tapered point type suture needle having a tapered body and a sharp needle tip, and a polygonal shape having a cutting blade. And a cutting edge type suture needle having a sharp toe. In addition, there are an eyeless needle and an eyed needle according to the attachment form of the suture. These suturing needles are selected and used according to the suturing site.

The thickness of the suturing needle is very thin, and the thickest suturing needle has a thickness of about 1.4 mm. Some suturing needles used for brain surgery and ophthalmic surgery have a thickness of 70 μm. The length of the suture needle is generally about 5 mm to 65 mm. In this way, the suture needle is tiny,
Therefore, there are many problems in fixing and positioning the material in the manufacturing process of the suture needle.

The suture needle is required to have characteristics such as low piercing resistance and sustained sharpness.

Further, as a material of the suture needle, martensitic stainless steel, precipitation hardening stainless steel, or the like is generally used. The martensitic stainless steel and the precipitation hardening stainless steel are both hardened by heat treatment.
Since there is no repetition stability due to the nature of the heat treatment, the hardness may vary. Further, the martensitic stainless steel has difficulty in corrosion resistance, and the precipitation hardening stainless steel has difficulty in cost. Further, in a suture needle hardened by quenching or a suture needle hardened by precipitation,
Since the hardness becomes hard, it is possible to maintain good piercing property and sharpness, but at the same time, there is a possibility that it may be destroyed due to its brittleness.

For this reason, the applicant of the present invention manufactures an ultra-fine medical device using a wire obtained by applying a cold drawing process to a wire made of austenitic stainless steel at a predetermined area reduction rate and hardening it, and using a wire obtained by elongating a metal structure into a fiber shape. A method has been developed (Japanese Patent Publication No. 1-11084).

A conventional manufacturing process of a suture needle using the austenitic stainless wire as a material will be described.

First, a line obtained as described in the above publication is cut into a predetermined length. The needle point or the needle point and the cutting edge are formed on the cut line by mechanical grinding, and the thread mounting portion is formed by press working or drilling, a laser beam, an electron beam, or the like. As described above, the line on which the needle tip, the cutting blade, the thread attaching portion, and the like are formed is bent into a predetermined shape by bending the line, thereby forming the material of the suture needle.

A material formed into a predetermined shape is immersed in a salt bath to perform a tempering treatment (aging treatment) to prevent a shape change with time. A chemical polishing process is performed to remove the temper color generated on the surface of the material during the tempering process and to smooth the surface of the material.

The suturing needle obtained as described above is subjected to a piercing inspection and an appearance inspection to determine a pass or a reject, and the passed one is packaged and shipped as a product.

In the manufacturing process, the forming of the austenitic stainless steel wire cut to a predetermined length is performed individually for each wire. In addition, for the tempering process and the polishing process for the material formed into a predetermined shape, a large number of materials are accommodated in a container, and the container is immersed in a salt bath,
Furthermore, it is immersed in a processing tank containing a chemical polishing treatment liquid for the treatment.

For this reason, the appearance inspection in the inspection process is performed by separating and aligning a large number of suture needles taken out of the container and piled up, and then the inspector uses a loupe to form a needle tip formed on the suture needle. , Cutting blade, thread mounting part, etc. are visually inspected.

<Problems to be Solved by the Invention> In the tempering process and the polishing process, in order to carry out the tempering process and the polishing process by accommodating a large number of materials formed into a predetermined bent shape in a container, There is a possibility that the material stored in the container may come into contact with the material and damage the needle tip or the cutting blade.

The tempering process is performed by a salt bath. This is because it is easy to keep the salt bath temperature in the salt bath constant, and it is possible to perform a tempering process on the material in a short time. However, there is a problem that a temper color is inevitably generated in the tempering process using a salt bath.

The polishing process is performed for the purpose of removing the temper color generated in the material by the emper treatment and smoothing the material surface. However, in the polishing process, a long time is required to remove the temper color. . When the polishing processing time becomes long, it is possible to achieve smoothness of the material surface, but there is a possibility that the sharpness of the needle point and the cutting edge formed on the material may be impaired.

Also, in the above inspection process, when separating and aligning individual suturing needles from a large number of sewn needles piled up, since the suturing needles are formed in a predetermined bent shape, the suturing needles may be intertwined. , May touch each other. For this reason,
The needle tip or the cutting blade may be damaged, and the piercing property may be reduced or the sharpness may be impaired.

An object of the present invention is to solve the above-mentioned problems and to provide a method of manufacturing a suture needle which can reduce the cost without lowering the penetrability and sharpness of the suture needle.

<Means for Solving the Problems> In order to solve the above problems, a method for manufacturing a suture needle according to the present invention includes a method for forming a wire formed by cold drawing an austenitic stainless steel wire at a predetermined area reduction rate. Forming a needle tip or a needle tip and a cutting edge and a thread attachment portion for attaching a suture to the cut line to produce a straight needle-shaped material; and A polishing process for smoothing the surface of the material, an inspection process for inspecting the appearance of the polished material, a bending process for bending the inspected material into a predetermined bending shape, and a predetermined bending shape And a heat treatment step of subjecting the bent material to a tempering treatment in a non-oxidizing atmosphere.

<Action> According to the above means, a needle-shaped material having a needle tip or a needle tip and a cutting blade formed on a wire of austenitic stainless steel cut to a predetermined length in a forming step and a thread attachment portion formed. Can be obtained.

In the polishing step, when performing the electropolishing treatment, since each material is independently connected to the electrode, there is no possibility that the materials come into contact with each other. Even when a large number of materials are subjected to the chemical polishing treatment, since the individual materials are straight needle-shaped, they do not become entangled with each other when many materials are stored in a container. For this reason, the polishing process can be performed without damaging the needle tips and cutting blades formed on the material.

Further, since the straight needle-shaped material after the molding step is polished, it is not necessary to remove the temper collar, and the polishing can be performed only for the purpose of smoothing the material surface. For this reason, the sharpness of the needle point, the cutting blade, etc. formed on the material is not impaired.

In the inspection process, when a large number of polished raw materials are piled up, the raw materials are straight needle-shaped, so there is no risk of entanglement with each other. In addition, the appearance inspection can be performed without damaging the needle tip or the cutting blade.

In addition, since the material has a straight needle shape, for example, when a positioning member or the like is provided and an axis serving as a reference is provided on the positioning member and the axis is aligned with the axis of the material, a needle point, a cutting blade, and a thread mounting portion are provided. Etc. can always be arranged at a fixed position. For this reason, by arranging optical means such as a CCD camera at a position corresponding to the needle tip, the cutting blade, and the thread mounting portion, the needle tip, the cutting blade,
By taking an image of the thread mounting portion and performing predetermined image processing on this image, it is possible to automate the appearance inspection of the material.

In the bending step, since only the material that has undergone the appearance inspection can be bent, efficient work can be performed.

In the heat treatment step, by performing tempering treatment on the material in a non-oxidizing atmosphere, a temper color is not generated in the material, and therefore, the material after the tempering treatment is directly commercialized as a suture needle. Can be done.

<Example> An example of a method for manufacturing a suture needle to which the above-described means is applied will be described below with reference to the drawings.

1 (A) to 1 (C) are explanatory diagrams of a suture needle, FIG. 2 is an explanatory diagram of a material of the suture needle, FIGS. 3 (A) and 3 (B) are schematic explanatory diagrams of a polishing process, FIG. (A), (B) is a schematic explanatory view of the inspection method.

 First, the shape of the suturing needle will be described.

The tapered point type suture needle 1 is configured as shown in FIGS. 1 (A) and 1 (B). That is, a sharp needle tip 1a is formed at one end, the body 1b is tapered toward the needle tip 1a, and the center is formed in a substantially cylindrical shape. A thread mounting portion 1c is formed at the opposite end of the needle tip 1a. Furthermore, the entire suture needle 1 is curved at a predetermined angle.

The cutting edge type suture needle 2 has a sharp needle tip 2a formed at one end as shown in FIG. 1C, and the body 2b is formed in a polygonal shape. A thread mounting portion 2c is formed at the opposite end of the needle tip 2a. A cutting edge 2d is formed near the needle tip 2a and at a ridge line forming a polygonal shape formed on the body 2b. Further, the entire suture needle 2 is curved at a predetermined angle.

FIGS. 3A and 3C show the through holes 1c and 2c of the thread mounting portions 1c and 2c, respectively.
The eye needle is constituted by c ₁ , 2c ₁ and configured so that a suture (not shown) can be passed through and held in the through holes 1c ₁ , 2c ₁ . FIG (B) is a thread attachment portion 1c constituted by a blind hole 1c _2, is inserted the end of the suture (not shown)該盲hole 1c _2, stitching the outer periphery of the blind hole 1c ₂ by caulking Figure 2 shows an eyeless needle configured to hold a thread.
FIG (B) is shows the case of forming the blind hole 1c ₂ the suture needle 1 of the taper point type, the eyeless needle formed a blind hole in the needle 2 of the cutting edge type may be used as well.

As the material constituting the suturing needles 1 and 2, a wire obtained by reducing the surface of an austenitic stainless steel wire (φ6 to φ10) to a desired diameter by cold drawing is used. This material has excellent corrosion resistance and good workability. However, since hardening by quenching cannot be expected, the steel sheet is hardened to a predetermined hardness by performing the cold drawing.

The austenitic stainless steel wire subjected to the cold drawing as described above has high hardness and high toughness (stickiness).

Next, a manufacturing method for manufacturing the suturing needles 1 and 2 having the above-described shape will be described.

The same molding process as the conventional molding process is used.
That is, an austenitic stainless wire that has been cold drawn to a diameter substantially equal to the diameter of the suture needles 1 and 2 is cut into a length substantially equal to the entire length of the suture needles 1 and 2.

When the tapered point type suture needle 1 is manufactured, a needle tip 1a is formed by mechanical grinding on the cut line, and a tapered shape having a predetermined angle is formed from the needle tip 1a to the body 1b. Further, it is formed in a cylindrical shape over the thread mounting portion 1c.

In the case of the cutting edge type suture needle 2, the needle tip 2a is formed by mechanical grinding on the cut line, and the trunk 2b is formed in a predetermined shape such as a triangular or quadrangular shape. It is formed in a cylindrical shape from 2b to the thread mounting portion 2c. At this time, a cutting edge 2d is formed on the ridge forming the polygon of the trunk 2b and near the needle tip 2a.

The suture needle 1 having the needle tip 1a and the torso 1b formed as described above,
Alternatively, an intermediate product of the suture needle 2 having the needle tip 1a, the trunk 2b, and the cutting blade 2d is manufactured.

Since the following steps are performed in the same manner on the taper point type suture needle 1 and the cutting edge type suture needle 2, the case of manufacturing the taper point type suture needle 1 will be described as a representative.

When forming the thread attachment portion 1c with respect to the intermediate product of the suture needle 1 having the needle tip 1a and the trunk portion 1b, the thread attachment portion 1c is formed by pressing to form the suture needle 1 as an eye needle. It is formed into an oval shape. And the thread mounting portion 1c
Or punching by press working, or a laser beam to form a through hole 1c ₁ shown in FIG. 1 by performing cutting process by a beam such as an electron beam (A). Further to configure the suture needle 1 as eyeless needle, the end face of the thread attachment portion 1c, or bored blind holes 1c ₂ using a drill, or a laser beam, a blind hole with an electron beam or the like 1c ₂ Drilling.

Through the above-described forming step, it is possible to produce the straight needle-shaped material 3 shown in FIG.

Fine irregularities are formed on the surface of the material 3 due to the effect of abrasive grains when mechanical grinding is performed. This material 3
The minute irregularities formed on the surface of the substrate have a bad influence on the piercing resistance.

Also, it has recently been found that fine burrs attached to the needle tip 1a of the material 3, particularly burrs attached to the cutting blade 2d of the cutting edge type suture needle 2, have a great effect on the piercing property.

The polishing step includes removing irregularities formed on the surface of the material 3,
That is, electrolytic polishing or chemical polishing is selectively performed for the purpose of smoothing the surface of the material 3 and removing burrs attached to the material 3.

FIG. 3 (A) is a schematic explanatory view for performing an electrolytic polishing process on the material 3. As shown in FIG.
Is attached to the electrode member 4, the electrode member 4 is connected to the power source 5, and is immersed in the electrolytic treatment solution contained in the tank 6 to conduct electricity between the electrode 7, thereby performing the electrolytic polishing treatment. It is configured to obtain.

At this time, since the material 3 has a straight needle shape, when the material 3 is attached to the electrode member 4, the individual material 3 does not come into contact with the adjacent other material 3, and accordingly, the needle tip 1 a or the cutting edge In the case of the suturing needle 2, there is no risk of damaging the needle tip 2a and the cutting blade 2d.

In the above configuration, when a DC power supply is used as the power supply 5, electricity is supplied using the electrode member 4 as an anode and the electrode 7 as a cathode. It is known that, when electrolytic polishing stainless steel, the treatment can be performed even by using an AC power supply. Therefore, power supply 5
May be either a DC power supply or an AC power supply.

In the electropolishing process, by appropriately setting processing conditions such as the composition of the processing solution, the temperature of the processing solution, the processing time, and the current density, the amount of metal removed, that is, the thickness of the removed layer on the surface of the material 3 It is possible to control the length. Therefore, by appropriately selecting the processing conditions according to the surface roughness of the material 3 or the state of burrs attached to the material 3, the surface can be smoothed and the needle tip 1a or the needle tip 2a can be cut. Burrs attached to the material 3 can be removed without impairing the sharpness of the blade 2d.

FIG. 3B is a schematic explanatory view for performing a chemical polishing treatment on the material 3. Many materials 3 as shown
Are housed side by side in a container 8 having liquid permeability,
By immersing the container 8 in a chemical polishing treatment liquid accommodated in a tank 9, a chemical polishing treatment can be performed.

When the raw materials 3 are arranged side by side in the container 8, since the raw materials 3 are formed in the shape of a straight needle, the individual raw materials 3 do not become entangled with other adjacent raw materials 3, and come into contact with each other to form a needle tip.
There is no risk of damaging sharpness such as 1a.

In the chemical polishing treatment, the thickness of the removal layer on the surface of the material 3 can be controlled by appropriately setting processing conditions such as the composition of the processing solution, the temperature of the processing solution, and the processing time. . Therefore, by appropriately selecting the processing conditions according to the surface roughness of the material 3 or the state of burrs attached to the material 3, the surface can be smoothed and the needle tip 1a can be formed.
Alternatively, the material 3 can be used without impairing the sharpness of the needle tip 2a and the cutting blade 2d.
Can be removed.

In the polishing step as described above, the surface of the material 3 is smoothed and the burrs attached to the material 3 are removed by subjecting the material 3 to electrolytic polishing or chemical polishing in which processing conditions are appropriately set. Becomes possible.

In the inspection step, an appearance inspection is mainly performed on the material 3 that has passed through the polishing step.

When this inspection is performed manually as shown in FIG. 4 (A), the materials 3 removed from the electrode members 4 are arranged side by side on a work table, and the materials 3 accommodated in the container 8 are placed on the work table. In a state where the individual materials 3 are taken out of the pile and arranged side by side, the inspector holds the
Perform a visual inspection with. At this time, since the raw materials 3 are straight needle-shaped, the individual raw materials 3 do not become entangled with other raw materials 3. For this reason, there is no possibility that the needle tips 1a and the like may be damaged due to the contact between the materials 3.

As described above, by inspecting the straight needle-shaped material 3 manually, the damage rate of the material 3 can be reduced.

Further, since the material 3 is formed in a straight needle shape, the inspection operation can be automated as described below.

In general, it cannot be said that the curved shape given to each material in the bending process can give the same shape to all the materials. That is, when a straight needle-shaped material is bent by a bending device, a variation occurs in a curved shape formed in the material due to a variation in an insertion depth when the material is inserted into the bending device, and a lot difference between materials constituting the material. For example, even if the insertion depth when inserting the material into the bending device is the same, the return amount (spring back amount) when the material is removed from the bending device is different,
Variations occur in the curved shape formed on the material. The variation in the curved shape is included in an allowable range set according to the standard of the suture needle, and does not cause any problem as to the quality of the suture needle.

However, the dispersion of the curved shape has become a serious problem when the inspection work is automated. As described above, when the suturing needle having a variation in the curved shape is fixed on the basis of, for example, the thread attachment portion, the position of the needle tip does not become a fixed position, and when the suturing needle is fixed on the basis of the needle tip, The position of the thread attachment part does not become a fixed position. For this reason, it is impossible to simultaneously photograph a needle tip, a cutting blade, a thread mounting portion, and the like formed on the material at a predetermined magnification by a CCD camera or the like.
It is difficult to perform effective automatic inspection work.

In the case where the material 3 is formed in a straight needle shape as in the present embodiment, the needle 1a, the thread attachment portion 1c, and the cutting edge type suture needle 2 formed on the material 3 are provided with a needle. Destination 2a,
Since the cutting blades 2d are located at predetermined positions on the axis of the material 3, it is easy to automate the inspection work.

FIG. 4B is a schematic explanatory view for automatically performing the appearance inspection work on the straight needle-shaped material 3.

In the figure, the material 3 is a blind hole 1c ₂ is configured as a material of the eyeless needle is formed in the thread attachment portion 1c. The plurality of blanks 3 are arranged at a fixed pitch via a spacer 11 having a fixed dimension. The material 3 is configured to be able to move at a constant speed by a driving device (not shown) or at a constant pitch according to the dimensions of the spacer 11.

CCD camera 12a is an extending direction of the axis of the material 3 is arranged in the thread attachment portion 1c side is for shooting at a set magnification according blind holes 1c ₂ to the thickness of the material 3. The CCD camera 12a is, if the material 3 which is a material of the idle needle is disposed at a position capable of capturing the hole 1c ₁ formed in the thread attachment portion 1c.

A CCD camera 12b is arranged on the needle tip 1a side of the material 3 at a predetermined angle with respect to the axis of the material 3. This CCD
The camera 12b photographs the needle tip 2a and the cutting edge 2d of the needle tip 1a formed on the material 3 and the cutting edge type suture needle 2 at a predetermined magnification.

The CCD cameras 12a and 12b are image processing devices 13a and 13b, respectively.
Is connected to the control device 14 via the. The control device 14
Image processing from the CPU, ROM storing the image information of the blind hole 1c ₂ with the allowable range set in advance, the needle information 1a, 2a and the cutting edge 2d with the allowable range similarly set, and image processing from the CCD cameras 12a, 12b. It is composed of a RAM that temporarily stores image information transmitted via the devices 13a and 13b. Then, the controller 14 compares the images captured by the CCD cameras 12a and 12b with the image information stored in advance to make a pass / fail judgment, and displays a pass / fail for each material 3 so as to perform a visual inspection. Is automatically implemented.

The automation of the inspection work as described above can be performed on condition that the material 3 is formed in a straight needle shape.

The bending step is performed in the same step as the bending step in the prior art. The straight needle-shaped material 3 is inserted into the bending device from the needle point 1a side, and is taken out of the bending device when the insertion length reaches a predetermined length, thereby giving the material 3 a predetermined curved shape.

In the heat treatment step, a tempering process is performed on the material 3 having a predetermined curved shape in the bending step.

In the tempering process, a plurality of curved raw materials 3 are accommodated in a container (not shown) in parallel, and the container is kept in an inert gas atmosphere such as a nitrogen gas or an argon gas.
Alternatively, it is performed in a non-oxidizing atmosphere such as a vacuum.
Then, in the non-oxidizing atmosphere, the material 3 is heated to about 300 ° C.
The material 3 is aged by performing a heat treatment for about 5 hours while maintaining the temperature of the material 3 to prevent the curved shape imparted in the bending step from being deformed over time.

As described above, in the manufacturing method according to the present invention, by performing the tempering process on the raw material 3 in the non-oxidizing atmosphere, there is no occurrence of the temper color which cannot be avoided in the related art. At the same time, the material 3 can be commercialized as the suture needle 1.

In the manufacturing method according to the present invention, the wire of the austenitic stainless steel is cut, and the needle tip 1a or the needle tip 2a, the cutting blade 2d,
The raw material 3 is formed in a straight needle shape having the thread mounting portions 1c and 2c formed thereon, and the raw material 3 is polished so that the surface of the raw material 3 is smoothed and the needle tip 1a or the needle of the raw material 3 is formed. The burrs attached to the tip 2a and the cutting blade 2d are removed with the needle tip 1a or the needle tip 2a,
The cutting edge 2d can be removed without impairing the sharpness.

<Effects of the Invention> As described in detail above, in the method of manufacturing a suture needle according to the present invention, by polishing the straight needle-shaped material formed in the forming step, the individual material is There is no danger of contact with other adjacent materials, so that the needle tips and cutting blades are not damaged by the contact between the materials.

Also, in the inspection process, when the material after polishing is piled up and the material is taken out from the pile, there is no danger of the materials being entangled with each other. Therefore, the needle tip and the cutting blade are damaged by the contact between the materials. Nothing to do.

In addition, since the inspection is performed on a straight needle-shaped material, the needle point, the cutting blade, and the thread attachment portion formed on the material are surely arranged at predetermined positions on the same axis, so that an optical Inspection work can be automatically performed using means or the like.

In addition, since the heat treatment step is performed in a non-oxidizing atmosphere, a tempered color does not occur on the surface of the tempered material, so that the material after the heat treatment can be commercialized as a suture needle. It has the feature of.

[Brief description of the drawings]

1 (A) to 1 (C) are explanatory diagrams of a suture needle, FIG. 2 is an explanatory diagram of a material of the suture needle, FIGS. 3 (A) and 3 (B) are schematic explanatory diagrams of a polishing process, FIG. (A), (B) is a schematic explanatory view of an inspection method. 1 is a taper point type suture needle, 2 is a cutting edge type suture needle, 1a and 2a are needle tips, 1b and 2b are a trunk, 1c and 2c are thread attachment parts, 1c ₁ is a through hole, 1c ₂ is a blind hole, 2d is a cutting blade, 3 is a material, 4 is an electrode member, 5 is a power supply, 6 and 9 are tanks, 7 is an electrode, 8 is a container, 1
0 is a loupe, 12a and 12b are CCD cameras, 13a and 13b are image processing devices, and 14 is a control device.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) A61B 17/06 A61L 17/00 A61L 31/00 B21G 1/02

Claims (1)

(57) [Claims] 1. A wire formed by cold-drawing an austenitic stainless steel wire at a predetermined area reduction rate to a predetermined length, and cutting the cut wire into a needle tip or a needle tip, a cutting blade and a suture. Forming a thread attaching portion for attaching a material to form a straight needle-shaped material, a polishing process for smoothing the surface of the material, and inspecting the appearance of the polished material. Production of a suture needle comprising: an inspection process, a bending process for forming the inspected material into a predetermined bending shape, and a heat treatment process of performing a tempering process on the material having the predetermined bending shape in a non-oxidizing atmosphere. Method.