JPH0596004A - Injector and production thereof - Google Patents

Abstract

PURPOSE:To provide the injector which prevents the bending and deforming of a discharge needle during operation and can exactly meter the samples discharged over a long period of time and discharge the samples and the process for production of the injector provided with the discharge needle having high straightness. CONSTITUTION:This injector has a syringe 10 having a fluid passage 13 formed continuously in a longitudinal direction, the discharge needle 12 which is mounted to the syringe and consists of the superelastic material contg. an Ni-Ti alloy contg. 50.2 to 52.0at.% Ni and consisting of the balance Ti and unavoidable impurities, and the plunger 11 which is inserted slidably with the inner peripheral surface of the fluid passage 13 from the other open end of the syringe 10 into the fluid passage. This process for production has a stage for subjecting the superelastic material contg. the Ni-Ti alloy to plastic working to obtain a tubular body having a prescribed shape and a stage for producing the discharge needle 12 by subjecting the tubular body to a heat treatment for shape memory for 2 to 120 minutes at 300 to 600 deg.C while applying tension thereto to maintain a straight shape.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a syringe and a method for manufacturing the same.

[0002]

2. Description of the Related Art Usually, a syringe comprises a syringe 10 made of glass or quartz, a plunger 11 made of glass or stainless steel, and a discharge needle 12 connected to the syringe, as shown in FIGS. There is. Syringe 10
A fluid passage 13 is formed continuously in the longitudinal direction, and accommodates a predetermined amount of sample (fluid such as liquid or gas) and chemicals. A scale 14 is marked on the outer peripheral surface of the syringe 10 so that the sample to be discharged can be measured. The measured sample is discharged from the discharge needle 12 by inserting the plunger 11 into the fluid passage 13.

In particular, a syringe called a microsyringe used for various kinds of analysis is used for accurately measuring a small amount of sample and injecting it into a measuring instrument or the like. Some can measure small quantities. In this microsyringe, the inner peripheral surface of the fluid passage 13 of the syringe 10 and the outer periphery of the plunger 11 are prevented so that the air can be prevented from entering the fluid passage 13 and the sample can be accurately measured. The surfaces have a precision mating structure. There is also a microsyringe in which a plunger can be inserted into the hole of the discharge needle.

Such a syringe is used very often. Therefore, the ejection needle or the plunger may be deformed during the work. That is, the ejection needle 12 is
When being inserted into a measuring instrument or the like for injecting a sample or the like, the plunger 11 is deformed at the insertion portion because it is pushed in a direction having a predetermined angle with respect to its axial direction, and the plunger 11 is The open end portion 1 of the syringe 10 is to be pushed in a direction having a predetermined angle with respect to the axial direction.
It deforms at 5 (the inlet of the fluid passage 13).

Even if either the discharge needle 12 or the plunger 11 is slightly bent, the outer peripheral surface of the plunger and the inner peripheral surface of the fluid passage of the syringe, or the outer peripheral surface of the plunger and the inner peripheral surface of the hole of the discharge needle. There is no precise matching in. As a result, it becomes impossible to measure and inject a small amount of sample precisely, and it does not serve as a syringe.

Therefore, conventionally, regarding the bending of the plunger, a protective tube made of Teflon or the like is arranged outside the syringe, but this is not preferable from the viewpoint of the operation of the plunger.
On the other hand, no measures have been taken to prevent bending of the discharge needle.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above point, and it is possible to accurately measure and eject a sample to be ejected over a long period of time by preventing the ejection needle from bending and deforming during work. An object of the present invention is to provide a syringe capable of being manufactured and a method of manufacturing a syringe having high straightness, that is, a syringe having a straight discharge needle.

[0008]

The present invention provides a syringe having a fluid passage formed continuously in the longitudinal direction, and a discharge needle attached to one open end of the syringe for discharging the fluid. And a plunger inserted into the fluid passage from the other open end of the syringe so as to be slidable on the inner peripheral surface of the fluid passage,
Provided is a syringe characterized in that a discharge needle contains 50.2 to 52.0 at% Ni, and the balance is made of a super elastic material containing Ti and a Ni—Ti based alloy which is an unavoidable impurity.

Further, according to the present invention, a step of subjecting a superelastic material containing a Ni-Ti alloy to plastic working to obtain a tubular body having a predetermined shape, and applying tension to the tubular body to maintain a linear shape And a step of producing a discharge needle by performing a heat treatment for shape memory at 300 to 600 ° C. for 2 to 120 minutes.

Here, the Ni--Ti alloy is V, Cr, F.
It is preferable to contain 3 at% or less of at least one element selected from the group consisting of e, Co, Mn, Cu, Pd, and Pt.

The content of Ni in the Ni-Ti alloy is 50.
When the ejection needle obtained is less than 2 at%, the residual strain becomes large when the ejection needle is bent, and the Ni content in the Ni—Ti alloy is 5 or less.
If it exceeds 2.0 at%, the workability becomes poor in production. In addition, V, Cr, Fe, Co, Mn in the Ni-Ti alloy,
At least one selected from the group consisting of Cu, Pd, and Pt
This is because if the content of the seed element exceeds 3 at%, the workability in manufacturing deteriorates.

The heat treatment for shape memory is performed while tension is applied to the object to be processed while maintaining the linear shape. This is to increase the straightness by applying tension to the object to be treated. The tension applied to the object to be treated is preferably 5 to 80 kgf / mm ² . This is because if the tension is less than 5 kgf / mm ² , the straightness of the discharge needle is not exhibited, and if the tension exceeds 80 kgf / mm ² , the discharge needle is permanently deformed. Because it breaks.

The heat treatment temperature for shape memory is 300 to 600.
Set to ° C. This is because the heat treatment temperature for shape memory is 30.
This is because if the temperature is lower than 0 ° C., the straightness of the discharge needle is not exhibited, and if the heat treatment temperature for shape memory exceeds 600 ° C., the surface oxidation of the discharge needle becomes severe. The heat treatment time for shape memory is set to 2 to 120 minutes. This is because if the heat treatment time for shape memory is less than 2 minutes, the straightness of the ejection needle is not exhibited, and if the heat treatment time for shape memory exceeds 120 minutes, it takes time, which is not preferable in manufacturing.

The heat treatment for shape memory may be carried out in a batch system in which the object to be processed is processed into a predetermined shape, or in a continuous system in which the object to be processed is run and passed through a heat treatment furnace. ..

After the heat treatment for shape memory, the object to be processed is subjected to mechanical treatment such as centerless polishing, chemical treatment such as pickling, and electrical treatment such as electrolytic polishing to be formed on the surface of the object. It is preferable in terms of use and hygiene to remove the oxide film.

[0016]

In the syringe of the present invention, the discharge needle contains Ni of 50.2 to
Since it is made of a superelastic material containing 52.0 at% and the balance of Ti and Ni--Ti based alloy which is an unavoidable impurity, it exhibits excellent recovery characteristics against bending deformation due to its superelastic effect.

The method for manufacturing a syringe according to the present invention is based on Ni
While tension is applied to a tubular body formed by subjecting a superelastic material containing a Ti-based alloy to plastic working to maintain a linear shape, 30
Since the heat treatment for shape memory is performed at 0 to 600 ° C. for 2 to 120 minutes, the ejection needle having high straightness can be obtained.

[0018]

EXAMPLES Examples of the present invention will be specifically described below.

Example 1 A tubular body having an outer diameter of 6 mm was obtained by welding both ends of a plate-like body having a thickness of 0.5 mm and made of a 50.8 at% Ni-Ti alloy with a laser. Then, this tubular body is repeatedly subjected to cold drawing and annealing to have an outer diameter of 0.5 mm and an inner diameter of 0.
A 12 mm discharge needle was used, and this discharge needle was subjected to heat treatment for shape memory so as to continuously form a linear shape. That is, the ejection needle was run while applying tension and passed through the heat treatment furnace.
In this way, the ejection needle of Example 1 was produced. The heat treatment condition for shape memory was 550 ° C. × 5 minutes, and the tension applied to the ejection needle was 10 kgf / mm ² .

The recovery characteristics against bending of the discharge needle of Example 1 manufactured in this way were examined. The results are shown in Table 1 below. Note that the recovery characteristics for bending are shown in FIG.
The discharge needle 30 was wound around a 15 mmφ stainless rod-shaped body 32 as shown in (4), and then the angle θ shown in FIG. 4 when the discharge needle was released was measured.

Examples 2-5, Comparative Examples 1-3 Materials shown in Table 1 below, heat treatment conditions for size and shape memory,
The ejection needles of Examples 2 to 5 and Comparative Examples 1 to 3 were produced in the same manner as in Example 1 except that the heat treatment method was adopted.

The recovery characteristics against bending of the obtained discharge needles of Examples 2 to 5 and Comparative Examples 1 to 3 were examined in the same manner as in Example 1. The results are also shown in Table 1 below.

Conventional Example A plate-like body having a thickness of 0.5 mm and made of SUS304 was welded to both ends by a laser to obtain a tubular body having an outer diameter of 6 mm. Then, this tubular body was repeatedly subjected to cold drawing and annealing to prepare a conventional discharge needle having an outer diameter of 0.5 mm and an inner diameter of 0.12 mm.

The recovery characteristic of the obtained conventional discharge needle against bending was examined in the same manner as in Example 1. The results are also shown in Table 1 below.

[0025]

[Table 1]

As is clear from Table 1, the ejection needles (Examples 1 to 5) of the syringe of the present invention exhibited excellent recovery characteristics against bending deformation. On the other hand, a discharge needle obtained by heat treatment conditions for shape memory outside the scope of the present invention (Comparative Example 1) and a discharge needle obtained using an alloy having a composition outside the scope of the present invention (Comparative Example 2) , 3), and the conventional discharge needles were found to be very weak against bending deformation.

[0027]

INDUSTRIAL APPLICABILITY As described above, the syringe of the present invention is capable of accurately measuring and discharging a sample to be discharged for a long period of time by preventing bending and deformation of the discharge needle during work, and a high straightness. It has a nature.

Further, according to the method for manufacturing a syringe of the present invention, it is possible to obtain a syringe having a discharge needle that exhibits excellent recovery characteristics against bending deformation.

[Brief description of drawings]

FIG. 1 is a front view showing an example of a syringe.

FIG. 2 is a front view showing another example of the syringe.

FIG. 3 is a diagram for explaining a method of evaluating a discharge needle.

FIG. 4 is an angle θ used when evaluating the deformation of the ejection needle.
FIG.

[Explanation of symbols]

10 ... Syringe, 11 ... Plunger, 12 ... Discharge needle,
13 ... Fluid passage, 14 ... Scale, 15 ... Open end.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI technical display location C22F 1/10 G 9157-4K (72) Inventor Mariko Wakie 2-6-1, Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd.

Claims (4)

[Claims] 1. A syringe having a fluid passage formed continuously in the longitudinal direction, a discharge needle attached to one open end of the syringe for discharging the fluid, and an inner circumference of the fluid passage. A syringe having a plunger inserted into the fluid passage from the other open end of the syringe so as to be slidable on a surface of the syringe, wherein the discharge needle has Ni of 50.2 to
A syringe comprising 52.0 at% and a balance made of a super elastic material containing Ti and an Ni-Ti alloy which is an unavoidable impurity. 2. The Ni—Ti alloy is V, Cr, F.
The syringe according to claim 1, containing 3 at% or less of at least one element selected from the group consisting of e, Co, Mn, Cu, Pd, and Pt. 3. A step of subjecting a superelastic material containing a Ni—Ti based alloy to plastic working to obtain a tubular body having a predetermined shape, and a step of applying tension to the tubular body to maintain a linear shape.
And a step of producing a discharge needle by performing heat treatment for shape memory at ˜600 ° C. for 2 to 120 minutes. 4. The method further comprising the step of removing the oxide film formed on the surface of the tubular body by a method selected from the group consisting of centerless polishing, pickling, and electrolytic polishing after the heat treatment for shape memory. 3. The method for manufacturing a syringe according to 3.