JP2001112871A - Needle and indwelling needle assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a needle capable of assuring a channel of blood, or the like, at an outer periphery and an indwelling needle assembly capable of being rapidly visually recognized for the indwelling needle (outer needle) to assure a blood vessel. SOLUTION: The indwelling needle assembly comprises an outer needle of an indwelling needle and an inner needle 4 used by inserting itself into the outer needle. The needle 4 has a sharp needle tip 41 at its end. A groove 46 is formed from the vicinity of a base end (root) of the tip 41 in an outer peripheral surface of the needle 4 along the longitudinal direction of the needle 4. The groove 46 forms a channel of a blood to allow to distribute the blood between the needle 4 and the outer needle. An S1/S2 is 0.005 to 0.15, wherein S1 is an area of the cross section of the groove 46 and S2 is an area surrounded by the outer edge profile line of the cross section of the needle 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a needle body and an indwelling needle assembly, and more particularly to a needle body for puncturing a blood vessel at the time of, for example, infusion or blood collection, and an indwelling needle assembly having the same.

[0002]

2. Description of the Related Art When infusion is performed on a patient, an indwelling needle connected to an infusion line is punctured into a blood vessel of the patient and is indwelled. Such an indwelling needle is constituted by a hollow outer needle, and when puncturing a blood vessel of a patient, a hollow inner needle having a sharp needle tip is inserted into the lumen of the outer needle, and the needle tip is inserted. The puncture operation is performed with the outer needle protruding from the tip.

[0003] When the inner needle reaches the inside of the blood vessel, the blood that has flowed through the opening of the needle tip flows through the lumen of the inner needle and into the transparent housing attached to the base end of the inner needle ( Flashback). Thereby, it can be confirmed that the inner needle has secured the blood vessel.

At this point, by slightly advancing the inner needle and the outer needle, the distal end of the outer needle is inserted into the blood vessel.

However, in the conventional indwelling needle assembly,
Since the inner peripheral surface of the distal end portion of the outer needle is in close contact with the outer peripheral surface of the inner needle, blood does not flow between the outer needle and the inner needle. It could not be confirmed visually by flashback.

For this reason, after confirming that the inner needle has secured the blood vessel, an operation of advancing the inner needle and the outer needle a delicate distance has been performed according to the feeling and experience of the operator. The distance from the tip of the outer needle is slightly different depending on the type, size, manufacturer, etc. of the indwelling needle assembly, and there is also a difference in the thickness of the blood vessel of the patient. This is not always the case, and the puncture position of the outer needle with respect to the blood vessel may be too shallow or too deep.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a needle body which can secure a flow path for blood or the like around the outer periphery of the needle body, and further that an indwelling needle (outer needle) secures a blood vessel. It is to provide an indwelling needle assembly that can be visually recognized.

[0008]

This and other objects are achieved by the present invention which is defined below as (1) to (13).

(1) A needle body having a sharp needle tip, wherein a concave portion which is recessed inside the outer peripheral surface of the needle body is formed in the outer peripheral portion along the longitudinal direction of the needle body, and crosses the concave portion. S ₁ the area of the surface, when the area surrounded by the outer edge contour of the cross section of said needle body has a S _2, S ₁ / S ₂ is 0.005 to 0.1
5. Needle body characterized by being 5.

(2) The needle according to the above (1), which satisfies S ₁ ≧ 0.002 mm ² .

(3) The needle according to the above (1) or (2), which satisfies S ₁ ≦ 0.05 mm ² .

(4) The needle body according to any one of (1) to (3), wherein the length of the recess in the needle body longitudinal direction is 1 mm or more.

(5) The needle body according to any one of (1) to (4), wherein an inclined blade surface is formed on the needle tip.

(6) The needle body according to the above (5), wherein the concave portion is formed along a longitudinal direction of the needle body from near a root of the needle tip on the blade surface side.

(7) The needle body according to any one of (1) to (6), wherein the recess is a chamfered portion formed by chamfering.

(8) The concave portion is a groove (1).
The needle according to any one of (1) to (6).

(9) The needle according to (8), wherein the groove is formed by press working.

(10) The needle according to any one of the above (1) to (9), wherein the needle has a tubular shape, and the thickness of the tube is substantially constant over the entire circumference including the portion where the concave portion is formed. Needle body.

(11) The needle body is used by puncturing a living body, and the concave portion constitutes a blood flow path (1).
The needle according to any one of (10) to (10).

(12) An indwelling needle assembly comprising a hollow outer needle and an inner needle inserted into a lumen of the outer needle, wherein the inner needle is any one of the above (1) to (11). An indwelling needle assembly, characterized by comprising the needle body of (1).

(13) The indwelling needle assembly according to the above (12), wherein the concave portion is formed at least in a portion of the outer peripheral portion of the inner needle which is in close contact with the outer needle.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a needle body and an indwelling needle assembly according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a longitudinal sectional view showing an embodiment of the indwelling needle assembly of the present invention, and FIG. 2 is a plan view showing the configuration near the tip of the inner needle in the indwelling needle assembly shown in FIG. 3 is FIG.
4 is a cross-sectional view taken along the line BB in FIG. 2, FIG. 5 is a cross-sectional view showing another configuration example of the inner needle, and FIG.
FIG. 4 is a longitudinal sectional view showing a configuration near a distal end portion in a state where an inner needle and an outer needle are assembled. In the following description,
1, 2, 3, and 6, the right side is referred to as a “proximal end”, and the left side is referred to as a “distal end”. The same applies to other drawings.

As shown in FIGS. 1 and 2, an indwelling needle assembly 1 according to the present invention has an outer needle 2 which is an indwelling needle, and an inner needle (needle body) used by being inserted into the outer needle 2. And 4.

A hub 3 is fixed to the proximal end of the outer needle 2 in a liquid-tight manner. The hub 3 is made of a transparent or translucent resin, and the visibility of the inside 31 is ensured.

As shown in FIG. 6, a reduced diameter portion 21 whose inner diameter is reduced is formed at the distal end of the outer needle 2. The inner diameter of the reduced diameter portion 21 is set to be substantially equal to or slightly smaller than the outer diameter of the inner needle 4 described later, and the inner needle 4 is inserted into the inner cavity of the outer needle 2 and the needle tip 41 is In a state where the outer needle 2 protrudes from the distal end opening 23 (hereinafter, this state is referred to as an “assembled state”), the inner peripheral surface of the reduced diameter portion 21 is configured to be in close contact with the outer peripheral surface of the inner needle 4. .

The inner diameter of the portion of the outer needle 2 closer to the base end than the reduced diameter portion 21 is larger than the outer diameter of the inner needle 4. A predetermined gap 22 is formed between the outer peripheral surface and the outer peripheral surface. This gap 22 becomes a blood flow path.

The distal end of the outer needle 2 has a tapered shape whose outer diameter gradually decreases toward the distal end. This makes it possible to puncture the living body easily and in a minimally invasive manner.

The constituent material of the outer needle 2 is not particularly limited, but for example, various soft resins such as ethylene-tetrafluoroethylene copolymer (ETFE), polyurethane, and polyether nylon resin are preferable.

It is preferable that all or a part of the outer needle 2 has visibility. Further, an X-ray contrast agent such as barium sulfate or barium carbonate may be blended in the constituent material of the outer needle 2 to provide a contrast function.

The inner needle 4 as a needle body of the present invention is, for example,
Stainless steel, aluminum or aluminum alloy,
Made of metal material like titanium or titanium alloy,
A sharp needle tip 41 is formed at the tip. The needle tip 41 has a blade surface 42 inclined at a predetermined angle with respect to the axis of the inner needle 4.

As shown in FIG. 1, the length of the inner needle 4 is set to such a length that at least the needle tip 41 projects from the distal end opening 23 of the outer needle 2 when assembled.

Although the outer diameter of the inner needle 4 is not particularly limited, it is usually preferably about 0.2 to 4.5 mm, preferably about 0.3 to 4.5 mm.
It is more preferably about 3.0 mm. The preferred outer diameter of the needle body is not limited to such a range except when the needle body of the present invention is applied to the inner needle 4 of the indwelling needle assembly 1.

At the base end of the inner needle 4, a hub (housing)
5 is fixed in a liquid-tight manner. The hub 5 is preferably made of a transparent or translucent resin, and the visibility of the inside 52 is ensured.

The distal end of the hub 5 has a connecting portion 51 having a reduced diameter.
Is formed, and generally, in the assembled state,
The connecting portion 51 of the hub 5 is in the proximal opening of the hub 3.

The constituent materials of the hub 3 and the hub 5 are as follows.
Examples thereof include polyolefins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, polyvinyl chloride, polymethyl methacrylate, polycarbonate, polybutadiene, polyamide, and polyester.

The inner needle 4 is formed with a concave portion which is recessed inward from the outer peripheral surface. In this embodiment, a predetermined portion of the inner needle 4 is chamfered as the concave portion, as shown in FIGS. More specifically, a strip-shaped chamfered portion which is flatly cut out at least in a portion of the outer peripheral portion of the inner needle 4 which is in close contact with the outer needle 2, that is, a portion which faces the reduced diameter portion 21 of the outer needle 2 in an assembled state. 43 are formed.

The chamfered portion 43 is provided on the blade surface 42 of the needle tip 41.
A length b is formed along the longitudinal direction (axial direction) of the inner needle 4 from the vicinity of the base end (root) on the side. Further, the maximum depth a of the chamfered portion 43 is less than the wall thickness of the tube wall of the inner needle 4.

In the present invention, the following conditions are imposed on the chamfered portion (recess) 43. That is, as shown in FIG. 4, the area of the cross section of the chamfered portion 43 (the area indicated by double oblique lines in FIG. 4) is S ₁ , and the area surrounded by the outer edge contour line of the cross section of the inner needle 4 (FIG. 4 (the area shown by oblique lines in the middle) is S _2, and S ₁ / S ₂ is preferably 0.005 to 0.15, more preferably 0.010 to 0.10.

If the value of S ₁ / S ₂ is too small, the resistance when blood passes through the chamfered portion 43 is large, and the time required to confirm that the tip of the outer needle 2 has secured a blood vessel by flashback is obtained. become longer. On the other hand, if the value of S ₁ / S ₂ is too large, the penetration resistance of the inner needle 4 into the living body increases, or the lumen of the inner needle 4 becomes thin, and the needle tip 42 of the inner needle 4 is flashed back. The time required to confirm that the blood vessel has been secured in the interior 52 becomes longer.

The preferred range of the area S ₁ is the inner diameter of the inner needle 4,
Usually, the area S ₁ is different depending on conditions such as the outer diameter.
Preferably, S ₁ ≧ 0.002 mm ² is satisfied, and S ₁ ≧
It is more preferable to satisfy 0.003 mm ² . Area S ₁
Is too small, the resistance when blood (liquid) passes through the chamfered portion 43 is large, and the time required to confirm that the tip of the outer needle 2 has secured a blood vessel by flashback becomes long.

The area S ₁ preferably satisfies S ₁ ≦ 0.05 mm ^2, and more preferably satisfies S ₁ ≦ 0.03 mm ² . If the area S ₁ is too large, piercing resistance to the inner needle 4 biological increases.

Incidentally, in the present invention can form a plurality of chamfered portions 43 with respect to the inner of one needle 4, in this case, the area S ₁ is the area of the sum of the chamfer 43. Further, the area of the cross section of the chamfered portion 43 may vary along the longitudinal direction of the inner needle 4, but in this case, the area S ₁ is an average of the area of the cross section at each point of the chamfered portion 43. Value.

The shape and dimensions of the chamfered portion 43 are as follows.
There is no particular limitation, and the maximum depth a is usually 0.01 to 0.80 m, although it depends on conditions such as the inner diameter and the outer diameter of the inner needle 4.
m is preferable, and about 0.03 to 0.30 mm is more preferable. The length b of the chamfered portion 43 is preferably 1 mm or more, more preferably about 1 to 65 mm, and 3 to 4 mm.
About 0 mm is more preferable. If the length b is too short, the function as a blood flow channel is not sufficiently exhibited, or the time required to confirm that the distal end of the outer needle 2 has secured a blood vessel by flashback becomes long.

Such a chamfered portion 43 can be formed at an arbitrary position on the circumference of the outer periphery of the inner needle. However, in order to confirm flashback (usually, the puncture is performed with the blade surface facing up). ), The needle tip 41 is preferably located at a position near the root (jaw) on the blade surface 42 side.

In FIG. 4, the wall thickness of the tube wall of the inner needle 4 in the portion where the chamfered portion 43 is formed is thinner than the other portions. However, as shown in FIG. The wall thickness of the tube wall can be made substantially equal to the wall thickness of other parts. Thereby, the strength of the portion of the chamfered portion 43 is increased, and the tube wall of the inner needle 4 can be made thinner. Such a configuration is obtained by forming the chamfered portion 43 by, for example, plastic working such as press working, as in the case of forming the groove 46 described later.

In the case where the chamfered portion 43 as shown in FIG. 5 is provided, the values of S ₁ / S _{2 and} the values of the area S ₁ , the maximum depth a, and the length b are the same as described above. is there.

By providing the above-described chamfered portion 43 on the inner needle 4, a gap 44 serving as a blood flow path is formed inside the reduced diameter portion 21 in the assembled state.
The distal end opening 23 of the outer needle 2 and the gap 22 communicate with each other through the through hole to form a continuous blood flow path.

The greatest advantage of providing the chamfered portion 43 is that it can be easily processed and formed. The details will be described below.

The chamfered portion 43 is formed by, for example, grinding,
The polishing can be performed by plastic processing such as polishing, laser processing, etching, and pressing. For example, when a groove is formed at the same position instead of the chamfered portion 43 by grinding or polishing, the relative movement of the grindstone with respect to the workpiece is set vertically,
It is necessary to control in the three-dimensional directions of width and depth. On the other hand, when the chamfered portion 43 of this embodiment is formed by the same method, since the chamfered portion 43 has a flat shape, the relative movement direction of the grindstone is controlled by the length of the inner needle 4. Only the two-dimensional direction of the direction and the depth direction is sufficient. In addition, a plurality of inner needles 4 can be arranged in a state where the direction of the blade surface 42 of the inner needles 4 and their tip positions are aligned, and chamfering can be performed on these at the same time.

Therefore, the chamfered portion 43 can be formed with a processing device having a simpler configuration, the processing accuracy is high, and the plurality of inner needles 4 can be collectively chamfered, thereby improving productivity. Dramatically improved.

Next, how to use the indwelling needle assembly 1 (operation).
An example will be described. [1] As shown in FIG. 1, the outer needle 2 and the inner needle 4 are assembled in advance. In such an assembled state of the indwelling needle assembly 1, the needle tip 41 projects from the distal end opening 23 of the outer needle 2,
The axial area of the reduced diameter portion 21 is included in the chamfered portion 43 of the inner needle 4.

It is preferable that this step has already been completed when the indwelling needle assembly 1 is used (when the packaging material is opened).

[2] The assembled inner needle 4 and outer needle 2 are percutaneously punctured into a blood vessel (vein or artery) of the patient.

When the needle tip 41 of the inner needle 4 is punctured into a blood vessel,
The blood flows backward in the inner needle 4 in the proximal direction due to the internal pressure (blood pressure) of the blood vessel, is introduced into the inside 52 of the hub 5, and the flashback can be visually recognized in the hub 5 having visibility. This makes it possible to know that the needle tip 41 of the inner needle 4 has secured a blood vessel.

When the inner needle 4 and the outer needle 2 are further advanced by a small distance, the tip of the outer needle 2 is inserted into the blood vessel. As a result, blood flows from the distal end opening 23, passes through the gap 44, and then flows toward the proximal end through the gap 22, and the hub 3
Is introduced into the interior 31. The flashback can be visually recognized by the outer needle 2 and the hub 3 having visibility. This makes it possible to know that the distal end of the outer needle 2 has secured a blood vessel.

At this time, since the values of S ₁ / S _{2 and} the like described above are set in appropriate ranges, the blood flows into the gaps 44 (chamfered) while preventing the resistance of the inner needle 4 from penetrating the skin. Part 4
3) Good flowability can be ensured when passing through, and it can be confirmed quickly (in a short time) that the distal end of the outer needle 2 has secured a blood vessel by flashback.

[3] Thereafter, the outer needle 2 alone is further moved in the blood vessel and introduced to a predetermined indwelling position.
Is held down with one hand, the hub 5 is gripped with the other hand and pulled in the proximal direction, and the inner needle 4 is pulled out of the outer needle 2.

[4] An infusion line is connected to the hub 3 via a connector (not shown), the outer needle 2 and the hub 3 are fixed with an adhesive tape or the like, and the infusion is supplied. Thus, the infusion is injected into the blood vessel of the patient via the outer needle 2.

FIGS. 7 and 8 are a perspective view and a plan view, respectively, showing the structure of the distal end portion of the inner needle according to another embodiment of the indwelling needle assembly of the present invention. FIG. 10 is a cross-sectional view taken along the line C-D in FIG. 8, and FIG. 11 is a vertical cross-sectional view showing a configuration near the distal end in an assembled state of the inner needle and the outer needle. Hereinafter, the embodiment shown in these figures will be described focusing on differences from the embodiment shown in FIGS.

As shown in FIGS. 7 to 11, a groove 46 extending along the longitudinal direction of the inner needle 4 is formed on the outer peripheral surface of the distal end portion of the inner needle 4 as a concave portion. The formation portion (formation region) of the groove 46 in the longitudinal direction of the inner needle is the chamfered portion 43.
This is almost the same as described in the above.

As shown in FIG. 11, in the assembled state,
The groove 46 formed in the inner needle 4 is located at a portion facing the reduced diameter portion 21 of the outer needle 2 and includes an axial region of the reduced diameter portion 21.

In this case, as shown in FIG.
It is preferable that the two edge portions 47, that is, the vicinity of the boundary between the groove 46 and the outer peripheral surface of the inner needle 4 are rounded (so-called R-shaped). If the edge portion 47 is sharply pointed, the inner surface of the outer needle 2 may be damaged when the inner needle 4 is inserted through the outer needle 2, but the edge portion 47 is rounded as described above. Such a problem does not occur. In addition, such a configuration can be applied to the chamfered portion 43 as well.

The grooves 46 are formed, for example, by grinding,
Although it may be formed by a method such as laser processing or etching, it is preferably formed by plastically deforming the inner needle 4 by plastic working, in particular, by pressing the inner needle 4. This allows grinding,
Compared to the case where the groove 46 is formed by laser processing or the like, the groove 4
It is difficult for sharp edges to be formed on both side portions of the edge portion 6. Even if secondary processing such as polishing or deburring is not performed to round the edge portion, the edge portion is rounded. The groove 46 having 47 can be easily formed.

On the inner surface of the inner needle 4 in the portion where the groove 46 is formed, a projecting portion 48 projecting into the inner cavity of the inner needle 4 is formed. Thereby, as shown in FIG. 10, the wall thickness of the tube wall of the inner needle 4 is substantially equal between the portion where the groove 46 is formed and the other portion, that is, over the entire circumference of the tube including the portion where the groove 46 is formed. Almost constant. For this reason, there is no reduction in strength at the portion where the groove 46 is formed, and even if the inner wall of the inner needle 4 has a relatively small wall thickness, deformation or breakage at the portion where the groove 46 is formed can be effectively prevented.

As shown in FIG. 8, the groove 46 is formed from the vicinity of the base end (root) of the needle tip 41 on the blade surface 42 side along the axial direction of the inner needle 4 for a length d.

As shown in FIG. 10, the area of the cross section of the groove 46 (the area shown by double oblique lines in FIG.
Assuming that S ₁ is the area inside the line segment connecting the lines 7 and 47, and S ₂ is the area surrounded by the outer edge contour of the cross section of the inner needle 4 (the area shaded in FIG. 10), S ₁ / S ₂ is 0.005
It is preferably 0.15, more preferably 0.01 to 0.10. The reason is that the chamfer 4
The same as in the case of No. 3.

The preferred range of the area S ₁ is the inner diameter of the inner needle 4,
Usually, the area S ₁ is different depending on conditions such as the outer diameter.
Preferably, S ₁ ≧ 0.002 mm ² is satisfied, and S ₁ ≧
It is more preferable to satisfy 0.003 mm ² . Also,
The area S ₁ preferably satisfies S ₁ ≦ 0.05 mm ^2, and more preferably satisfies S ₁ ≦ 0.03 mm ² .
These reasons are the same as in the case of the chamfered portion 43.

In the present invention, a plurality of grooves 46 can be formed for one inner needle 4. In this case, the area S ₁ is the total area of each groove 46. Also, groove 4
6 may vary along the longitudinal direction of the inner needle 4, but in this case, the area S ₁ is an average value of the area of the cross section at each point of the groove 46.

The shape and size of such a groove 46 are not particularly limited, and vary depending on conditions such as the inner diameter and the outer diameter of the inner needle 4, but usually the maximum depth c is 0.01 to 0.80 mm. The width is preferably about 0.03 to 0.30 mm, and the width e of the groove 46 is preferably about 0.05 to 1.60 mm, and more preferably about 0.10 to 1.00 mm.
The length d of the groove 46 is preferably 1 mm or more,
About 65 mm is more preferable, and about 3 to 40 mm is still more preferable. The reason is the same as in the case of the chamfered portion 43.

The cross-sectional shape, maximum depth, width and the like of the groove 46 may be the same or may vary along the longitudinal direction of the inner needle 4. For example, the groove 46 may have a portion (particularly a proximal portion) whose maximum depth and / or width gradually decreases (or increases) in the proximal direction.

In the illustrated example, a projection 48 is formed on the inner surface of the inner needle 4 at the portion where the groove 46 is formed, and the projection 48 projects into the lumen of the inner needle 4. It may not be.

The groove 46 is not limited to a linear one as shown, but may be, for example, an appropriately curved one, a meandering one, or a spiral one.

Further, a plurality of grooves 46 are provided for one inner needle 4.
When forming the groove, the positional relationship between the grooves 46 may be any such as those arranged in parallel with each other, those arranged at a predetermined angle, and those crossing each other. Further, one groove 46 may be branched into a plurality of grooves in the middle.

According to the above-described plastic working, even a plurality of such grooves 46 or grooves 46 having a complicated shape can be easily formed.

The indwelling needle assembly having such a configuration that the inner needle 4 has the groove 46 is also used in the same manner as in the above embodiment. In this case, in the step [2], when the distal end of the outer needle 2 is inserted into the blood vessel, the blood flows into the distal opening 23.
And flows through the inside of the groove 46,
Flows toward the proximal direction, and is introduced into the interior 31 of the hub 3. Then, the flashback can be visually recognized by the outer needle 2 and the hub 3 having visibility, whereby it is possible to know that the distal end of the outer needle 2 has secured a blood vessel.

Hereinafter, a preferred example of a method of manufacturing the needle body (the inner needle 4) having the above-described groove 46, particularly a preferred example of a method of forming the groove 46 by plastic working (pressing) will be described with reference to FIGS. explain.

First, a blade surface 42 is formed at the end of the tube constituting the inner needle 4. The method of forming the blade surface 42 is not particularly limited, and for example, can be performed by a conventional method such as cutting, grinding, polishing, or laser processing.

Next, a groove 46 is formed by using a press machine 10 as shown in FIG. The press machine 10 includes a main body 100.
And a female mold (lower mold) 101 and a male mold (upper mold) 102.
Is mounted movably in the vertical direction in FIGS. 12 to 15 with respect to the female mold 101.

The female mold 101 has a U-shaped groove 104 into which the inner needle 4 is inserted. In this case, the width of the groove 104 is set to be substantially the same as the outer diameter of the inner needle 4 or a value slightly larger than the outer diameter of the inner needle 4, and the inner needle 4 is pressed in the lateral direction (the direction perpendicular to the pressing direction) during pressing. Prevents collapsing.

At one end of the groove 104 of the female mold 101, a positioning portion 103 formed in a U-shape (overhang shape) is formed. As shown in FIG. 13, when the inner needle 4 is inserted into the groove 104 and the inner needle 4 is moved in the distal direction in the groove 104, the blade surface 42 of the inner needle 4
The inner needle 4 is positioned such that the blade surface 42 faces upward. Thereby, the male mold 10
2. When pressed at 2, the needle tip 41
A groove 46 is formed at a position extending along the longitudinal direction of the inner needle 4 from the vicinity of the base end (root portion) on the blade surface 42 side.

The male mold 102 is installed so as to be slidable in the vertical direction in FIG. On the lower surface of the male mold 102, a projection (projection) 105 for forming the groove 46 in the inner needle 4 is formed. The protrusion 105 extends in parallel with the groove 104 formed in the female mold 101, and has a length substantially equal to the length d of the groove 46 to be formed. Also, the protrusion 105
Has a V-shape (crest shape).

In the state where the inner needle 4 is inserted into the groove 104 and the positioning is performed as described above (the state shown in FIGS. 12 to 14), the operating lever (or handle) (not shown) is operated to Mold 102 into female mold 10
When descending until it collides with 1, as shown in FIG.
The convex portion 105 of the male mold 102 presses the tube wall of the inner needle 4 to plastically deform it, thereby forming the groove 4 as described above.
6 are formed.

At this time, the tube wall of the portion pressed by the convex portion 105 escapes to the inner cavity side of the inner needle 4 to form the projecting portion 48, so that the wall thickness of the tube of the inner needle 4 is It becomes substantially constant over the entire circumference of the tube including the formed portion.

Further, since the outer peripheral surface of the inner needle 4 is restricted by the inner surface of the groove 104, the contour of the inner needle 4 (the circular shape ) Is not significantly impaired.

After the grooves 46 are formed as described above, the male mold 102 is raised and the male mold 102
And the inner needle 4 is taken out of the groove 104.

Manufacturing of such inner needle 4 (formation of groove 46)
Can be repeated for a plurality of similar inner needles 4.

It should be noted that the groove 46 is formed by such press working.
When forming the inner needle 4, the processing conditions are not particularly limited, and are appropriately determined according to conditions such as the material, the inner diameter, and the thickness of the inner needle 4. Usually, the pressing pressure is 1000 to 15000 kg / cm ^2.
Degree is preferable, and about 2,000 to 10,000 kg / cm ² is more preferable.

The method of positioning the inner needle 4 is not limited to the method described above. For example, the inner needle 4 may be chucked (not shown).
It is also possible to adjust the position where the groove 46 is formed while checking the direction (position) of the blade surface 42 of the inner needle 4 with one or two or more cameras.

Further, one groove 46 can be formed by two or more pressing steps. In this case, in each pressing step, the male mold 102 can be appropriately replaced with a different one in which the shape and the formation position of the convex portion 105 are different. Thereby, it becomes possible to form the groove 46 having a more complicated shape.

When a plurality of grooves 46 are formed in one inner needle 4, the inner needle 4 may be pressed a plurality of times by the male mold 102 while rotating the inner needle 4 in the groove 104 by a predetermined angle.

Further, for example, by using a plurality of processing dies, grooves 46 can be formed in a plurality of inner needles 4 at a time, and productivity can be improved. For example,
When the press 10 is used, a plurality of grooves 104 are formed in the female mold 101, a plurality of protrusions 105 corresponding to each groove 104 are formed in the male mold 102, and a plurality of inner needles are simultaneously formed by a single press. 4 can be formed with a groove 46.

According to the method of manufacturing the inner needle 4 as described above,
The groove 46 having the appropriate shape can be formed at the appropriate position with good reproducibility, and the operation is extremely simple. Therefore, the productivity of the inner needle 4 and the indwelling needle assembly 1 including the same can be improved.

Although the indwelling needle assembly of the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to this. Each member constituting the indwelling needle assembly has the same function. Can be replaced with any structure that can exhibit the following.

Further, as the concave portion formed in the inner needle 4, the chamfered portion 43 and the groove 46 have been described.
The form is not limited to these.

Further, the concave portions such as the chamfered portion 43 and the groove 46 described above may be formed at locations other than the close contact portion between the outer needle 2 and the inner needle 4. It may be formed over the entire length.

In the above, the inner needle 4 in the indwelling needle assembly has been described as an example of the needle body of the present invention. However, the needle body of the present invention is not limited to such an inner needle. For example, a needle used in combination with an outer needle other than an indwelling needle, a tube such as a catheter or a sheath, or a needle used alone may be used.

[0098]

As described above, according to the present invention, it is possible to form a flow path for blood or the like by the concave portion in the outer peripheral portion of the needle body, and to ensure good flowability of the liquid in the flow path. can do.

In particular, when the needle is applied to the inner needle of the indwelling needle assembly, the blood passes through the concave portion and the inner needle and the outer needle (indwelling needle).
Since it flows in between, it is possible to visually recognize that the outer needle has secured the blood vessel, and this visual recognition can be quickly performed. In addition, the fact that the inner needle has secured the blood vessel can also be quickly visually recognized.

Further, in the needle body of the present invention, since the increase in puncture resistance is suppressed, the puncture operation can be performed easily and accurately, and the pain when piercing the living body can be reduced. it can.

Thus, the puncture operation of the inner needle and the outer needle into the blood vessel can be performed easily and accurately.

Further, the needle body and the indwelling needle assembly of the present invention are easy to manufacture and process, have high processing accuracy, and have good yield. In particular, since it is possible to simultaneously process a plurality of needle bodies or perform continuous processing, the production efficiency is high, and therefore, it is suitable for mass production.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of an indwelling needle assembly of the present invention.

FIG. 2 is a plan view showing the configuration near the distal end of an inner needle in the indwelling needle assembly shown in FIG.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a sectional view taken along line BB in FIG. 2;

FIG. 5 is a cross-sectional view showing another configuration of the inner needle.

FIG. 6 is a vertical cross-sectional view showing a configuration near a front end in an assembled state.

FIG. 7 is a perspective view showing a configuration of a distal end portion of an inner needle according to another embodiment of the indwelling needle assembly of the present invention.

FIG. 8 is a plan view showing a configuration of an inner needle tip portion according to another embodiment of the indwelling needle assembly of the present invention.

9 is a sectional view taken along line CC in FIG.

FIG. 10 is a sectional view taken along line DD in FIG. 8;

FIG. 11 is a longitudinal sectional view showing a configuration near a tip end in an assembled state.

FIG. 12 is a perspective view showing an example of a method for manufacturing an inner needle.

FIG. 13 is a sectional view taken along line EE in FIG. 12;

14 is a cross-sectional view (before pressing) taken along line FF in FIG.

FIG. 15 is a cross-sectional view taken after the FF line in FIG. 12 (after pressing).

[Explanation of symbols]

 Reference Signs List 1 indwelling needle assembly 2 outer needle (indwelling needle) 21 reduced diameter portion 22 gap 23 tip opening 3 hub 31 inside 4 inner needle 41 needle tip 42 blade surface 43 chamfered portion 44 void 46 groove 47 edge portion 48 protruding portion 5 hub 51 Connecting part 52 Inside 10 Press machine 100 Main body 101 Female mold 102 Male mold 103 Positioning part 104 Groove 105 Convex part 106 Sliding part

Claims (13)

[Claims] 1. A needle body having a sharp needle tip, wherein a recess recessed inward from the outer peripheral surface of the needle body is formed in an outer peripheral portion along a longitudinal direction of the needle body, and a cross section of the recess is provided. the area S _1, when the area surrounded by the outer edge contour of the cross section of said needle body has a S _2, the needle body that S ₁ / S ₂ is characterized in that it is a 0.005 to 0.15. 2. The needle body according to claim 1, wherein S ₁ ≧ 0.002 mm ² is satisfied. 3. The method according to claim 1, wherein S ₁ ≦ 0.05 mm ² is satisfied.
Or the needle according to 2. 4. The length of the recess in the longitudinal direction of the needle body is 1 mm.
The needle according to any one of claims 1 to 3, which is as described above. 5. The needle body according to claim 1, wherein an inclined blade surface is formed on the needle tip. 6. The needle body according to claim 5, wherein the recess is formed along a longitudinal direction of the needle body from near a root of the needle tip on the blade surface side. 7. The needle body according to claim 1, wherein the recess is a chamfer formed by chamfering. 8. The method according to claim 1, wherein the recess is a groove.
The needle according to any one of the above. 9. The needle according to claim 8, wherein the groove is formed by press working. 10. The needle body according to claim 1, wherein the needle body has a tubular shape, and the wall thickness of the tube is substantially constant over the entire circumference including a portion where the concave portion is formed. 11. The needle according to claim 1, wherein the needle is used by puncturing a living body, and the recess forms a blood flow path. 12. An indwelling needle assembly comprising a hollow outer needle and an inner needle inserted into a lumen of the outer needle, wherein the inner needle is any one of claims 1 to 11. An indwelling needle assembly comprising a body. 13. The indwelling needle assembly according to claim 12, wherein the concave portion is formed on at least a portion of the outer peripheral portion of the inner needle which is in close contact with the outer needle.