JPH1189939A - Manufacture of indwelling needle assembly and inner needle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indwelling needle assembly which is easy to manufacture and allows viewing that an indwelling needle has secured a blood vessel. SOLUTION: An indwelling needle assembly has an outer needle 2 serving as an indwelling needle and an inner needle 4 used when inserted into the outer needle 2. A reduced diameter part 21 that makes intimate contact with the outer peripheral surface of the inner needle 4 is formed at the end of the outer needle 2, and a gap is formed between a portion beyond the reduced diameter part 21 and close to a first end and the inner needle 4. A tip 41 having a slanted blade surface 42 is formed at the end of the metallic inner needle 4. A groove 46 is formed along the longitudinal direction of the inner needle 4, in the part of the outer periphery of the inner needle 4 making intimate contact with the outer needle 2, i.e., the part opposite to the reduced diameter part 21 when in an assembled state. A blood flow passage is formed inside the reduced diameter part 21 by the groove 46. The groove 46 is formed by press working, the wall thickness of the tube of the inner needle 4 being almost uniform throughout the periphery of the assembly including the part where the groove 46 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indwelling needle assembly for puncturing and indwelling a blood vessel during, for example, infusion, and a method for manufacturing an inner needle constituting the indwelling needle assembly.

[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 blade surface inclined at the needle tip is inserted into the lumen of the outer needle, and The puncture operation is performed with the needle tip protruding from the tip of the outer needle.

[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 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. Could not be confirmed visually.

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 surgeon. 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 an indwelling needle assembly and a method for manufacturing an inner needle which are easy to manufacture and which can visually confirm that an indwelling needle (outer needle) has secured a blood vessel. To provide.

[0008]

This and other objects are achieved by the present invention which is defined below as (1) to (17).

(1) An indwelling needle assembly comprising a hollow outer needle and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. Of the outer periphery of
An indwelling needle assembly, wherein at least a portion in close contact with the outer needle is chamfered.

(2) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. On the outer periphery of
An indwelling needle assembly, characterized in that the indwelling needle assembly has a portion that is chamfered along the axial direction of the inner needle from near the root of the blade surface.

(3) An indwelling needle assembly comprising a hollow outer needle and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. Of the outer periphery of
An indwelling needle assembly, characterized in that at least a portion in close contact with the outer needle is roughened.

(4) An indwelling needle assembly comprising a hollow outer needle and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the inner needle. On the outer periphery of
An indwelling needle assembly, characterized in that the indwelling needle assembly has a portion that has been roughened along the axial direction of the inner needle from near the root of the blade surface.

(5) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip thereof. An indwelling needle assembly, wherein a groove formed by plastically deforming the inner needle is provided at least in a portion in close contact with the outer needle.

(6) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, wherein a groove formed by plastically deforming the inner needle is provided along the axial direction of the inner needle from near the root of the blade surface.

(7) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. A groove is provided at least in a portion in close contact with the outer needle, and a wall thickness of the tube of the inner needle is substantially constant over an entire circumference including a portion where the groove is formed.

(8) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. A groove is provided along the axial direction of the inner needle from near the root of the blade surface,
The indwelling needle assembly, wherein the thickness of the tube of the inner needle is substantially constant over the entire circumference including the portion where the groove is formed.

(9) The indwelling needle assembly according to (7) or (8), wherein the groove is formed by plastically deforming the inner needle.

(10) The plastic deformation is performed by press working (5), (6) or (9).
An indwelling needle assembly according to item 1.

(11) The indwelling needle assembly according to any one of (5) to (10), wherein the vicinity of the boundary between the groove and the outer peripheral surface of the inner needle is rounded.

(12) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. Of the inner circumference of
An indwelling needle assembly, wherein a void serving as a blood flow path is formed at least in a portion in close contact with the inner needle.

(13) An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. At the tip of
The inner diameter is reduced in diameter, and has a reduced diameter portion in close contact with the inner needle,
An indwelling needle assembly, wherein a void serving as a blood flow path is formed on an inner peripheral surface of the reduced diameter portion.

(14) A method for manufacturing an inner needle which is used by being inserted into the lumen of a hollow outer needle and has an inclined blade surface at the needle tip, wherein the step of forming the blade surface includes the steps of: Forming a groove by plastic working at least in a portion of the needle that is in close contact with the outer needle.

(15) A method for manufacturing an inner needle which is used by being inserted into the lumen of a hollow outer needle and has an inclined blade surface at the needle tip, wherein the step of forming the blade surface, Forming a groove by plastic working from near the base of the surface along the axial direction of the inner needle.

(16) The groove is formed such that the thickness of the tube of the inner needle is substantially constant over the entire circumference including the portion where the groove is formed. 3. The method for producing an inner needle according to item 1.

(17) The method for manufacturing an inner needle according to any one of the above (14) to (16), wherein the formation of the groove is performed while positioning with reference to the position of the blade surface.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing an indwelling needle assembly and an inner needle 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.
FIG. 4 is a cross-sectional view taken along the line AA in FIG. 2, FIG. 4 is a cross-sectional view taken along the line BB in FIG. 2, and FIG. is there. In the following description, the right side in FIGS. 1, 2, 3 and 5 is referred to as a “proximal end”, the left side is referred to as a “distal end”, and the same applies to other drawings.

As shown in FIGS. 1 and 2, the indwelling needle assembly 1 of the present invention has an outer needle 2 which is an indwelling needle and an inner needle 4 which is used by being inserted into the outer needle 2. doing.

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. 5, the distal end of the outer needle 2 has a reduced diameter portion 21 whose inner diameter is reduced.
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
It is configured to be in close contact with the outer peripheral surface of.

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, and the inner peripheral surface of the reduced diameter portion 21 and the inner needle 4 are assembled in the assembled state. 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. 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 is made of, for example, a metal material such as stainless steel, aluminum or an aluminum alloy, titanium or a titanium alloy, and has a sharp needle tip 41 formed at its tip. This needle tip 41 is the inner needle 4
Has a blade surface 42 inclined at a predetermined angle with respect to the axis.

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.

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.

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

As shown in FIGS. 2 to 5, a predetermined portion of the inner needle 4 is chamfered. 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 has a length b along the axial direction of the inner needle 4 from near the base end (root portion) of the blade surface 42.

The maximum depth a of the chamfered portion 43 is less than the thickness of the tube of the inner needle 4. The shape and dimensions of the chamfered portion 43 are not particularly limited as long as they can cover the contact portion between the inner needle 4 and the outer needle 2, but in the case of the illustrated configuration, the length b is 1 to 20 mm. Preferably about 1 to 10 mm
The degree is more preferred. The maximum depth a is 0.01 to
It is preferably about 0.2 mm, more preferably about 0.03 to 0.15 mm.

The chamfered portion 43 can be formed at an arbitrary position on the circumference of the outer periphery of the inner needle.
It is preferable that the blade face 42 is located near the root (jaw portion) of the blade surface 42 because of the easiness of forming the workpiece.

In FIG. 4, the thickness of the tube of the inner needle 4 at the portion where the chamfered portion 43 is formed is thinner than the other portions. However, when the chamfered portion 43 is formed by pressing, for example, a groove to be described later is used. 46, as in the case of forming the chamfer 4
The wall thickness of the tube of the inner needle 4 at the portion 3 can be made substantially equal to the wall thickness of the other portions.
The strength of the part increases.

By providing the inner needle 4 with the chamfered portion 43 as described above, 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.

Accordingly, the chamfered portion 43 can be formed by 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 the assembled state of the indwelling needle assembly 1, the needle tip 41 protrudes from the distal end opening 23 of the outer needle 2, and the axial area of the reduced diameter portion 21 is included in the chamfered portion 43 of the inner needle 4. You.

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 punctured into a blood vessel (vein or artery) of the patient.

When the 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.

[3] After that, only the outer needle 2 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] The 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. 6 and 7 are perspective views showing the configuration of the distal end of the inner needle according to another embodiment of the indwelling needle assembly of the present invention, and the vicinity of the distal end in an assembled state of the inner needle and the outer needle. It is a longitudinal cross-sectional view which shows a structure of. Hereinafter, the embodiment shown in these figures will be described focusing on differences from the embodiment shown in FIGS.

As shown in FIG. 6, the outer peripheral surface of the tip of the inner needle 4 is roughened to form a rough surface 45, that is, a surface having many minute irregularities. .
Formed part (formation area) of this rough surface 45 in the longitudinal direction of the inner needle
Is substantially the same as the chamfered portion 43.

As shown in FIG. 7, in the assembled state, the rough surface 45 formed on the inner needle 4 is located at a portion facing the reduced diameter portion 21 of the outer needle 2 and Region.

The indwelling needle assembly having such a structure that the inner needle 4 has the rough surface 45 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 2.
3, passes through a number of minute concave portions in the rough surface 45, and then flows toward the proximal direction through the gap 22, 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.

The rough surface 45 can be formed only on a part of the outer circumference of the inner needle in the circumferential direction. However, in order to secure the area of the blood flow channel on the rough surface 45 as large as possible, As shown in the figure, the inner needle is preferably formed all around the outer circumference.

The roughness of the rough surface 45 is not particularly limited.
The center line average roughness Ra specified in JIS B 0601 is 10 to 5
It is preferably about 00 μm, more preferably about 50 to 200 μm. With such a roughness, rough surface processing is easy and blood flow on the rough surface 45 can be sufficiently ensured.

The greatest advantage of providing the rough surface 45 is that its processing and formation are easy. The details will be described below.

The formation of the rough surface 45 can be performed, for example, by masking a region other than the rough surface forming portion of the inner needle 4 and then performing sand blasting, shot blasting, etching, or the like.

Further, a plurality of inner needles 4 are arranged in a state where the direction of the blade surface 42 of the inner needles 4 and the positions of their tips are aligned, and roughening is simultaneously performed on these by the above-described processing method. Can greatly improve productivity.

FIGS. 8 and 9 are a perspective view and a plan view, respectively, showing the configuration of the tip of the inner needle according to another embodiment of the indwelling needle assembly of the present invention. FIG. FIG. 11 is a cross-sectional view taken along line C-D in FIG. 9, and FIG. 12 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. 8 to 12, a groove 46 extending along the longitudinal direction of the inner needle 4 is formed on the outer peripheral surface of the tip of the inner needle 4. The formation portion (formation region) of the groove 46 in the longitudinal direction of the inner needle is substantially the same as the chamfered portion 43.

As shown in FIG. 12, 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. 11, both edges 47 of the groove 46, 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). ) Is preferred. If the edge portion 47 is sharply sharpened, the inner surface of the outer needle 2 may be damaged when the inner needle 4 is inserted through the outer needle 2.
If the 7 is rounded, such an inconvenience does not occur.

The groove 46 is formed by plastically deforming the inner needle 4 by plastic working, preferably by pressing the inner needle 4. Grinding,
When the groove 46 is formed by laser processing or the like, sharply sharp edges are easily formed on both sides of the groove 46, and secondary processing such as polishing or deburring is performed to round the edge. Required, complicating the manufacturing process,
When the groove 46 is formed by plastically deforming the inner needle 4 by press working or the like, the groove 46 having the rounded edge portion 47 can be easily formed without performing the above-mentioned secondary processing.

On the inner surface of the inner needle 4 in the portion where the groove 46 is formed, a protruding portion 48 is formed to protrude into the lumen of the inner needle 4. Thereby, as shown in FIG. 11, the thickness of the tube of the inner needle 4 is substantially equal between the portion where the groove 46 is formed and the other portion,
That is, it is substantially constant over the entire circumference of the tube including the portion where the groove 46 is formed. For this reason, there is no reduction in strength in the portion where the groove 46 is formed, and even if the tube of the inner needle 4 is relatively thin, deformation or breakage in the portion where the groove 46 is formed can be effectively prevented.

As shown in FIG. 9, the groove 46 is formed from the vicinity of the base end (root) of the blade surface 42 by a length d along the axial direction of the inner needle 4.

The shape and size of the groove 46 are not particularly limited as long as they can cover the contact portion between the inner needle 4 and the outer needle 2, but in the case of the configuration shown, the maximum depth c of the groove 46 is ,
About 0.01 to 0.3 mm is preferable, and 0.03 to 0.1
The length d is preferably about 5 mm, and the length d is preferably about 1 to 30 mm, and more preferably about 1 to 15 mm. Also, groove 4
6 is preferably about 0.1 to 1.0 mm, and 0.2
It is more preferably about 0.5 mm.

Further, 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 projecting into the inner cavity of the inner needle 4 is formed on the inner surface of the inner needle 4 in the portion where the groove 46 is formed. 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.

A plurality of grooves 46 may be formed. In this case, the positions of the grooves 46 may be parallel to each other, may be arranged at a predetermined angle, or may be crossed. Anything may be used. Further, one groove 46 may be branched into a plurality of grooves in the middle.

According to the above-mentioned 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 structure that the inner needle 4 has the groove 46 is also used in the same manner as that of 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 inner needle 4 having the above-described groove 46, particularly a method of forming the groove 46 by plastic working (pressing) will be described.

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 installed movably in the vertical direction in FIGS. 13 to 16 with respect to the female mold 101.

The female mold 101 is formed with 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. 14, when the inner needle 4 is inserted into the groove 104 and the inner needle 4 is moved in the tip 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
When pressed at 2, the blade face 42
A groove 46 is formed at a position extending in the axial direction of the inner needle 4 from near the base end (root) of the inner needle 4.

The male mold 102 is installed so as to be slidable vertically with respect to the sliding portion 106 of the main body 100 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 a 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. 13 to 15), an operating lever (or handle) (not shown) is operated to Mold 102 into female mold 10
When it is lowered 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 inner needle 4 may be flattened due to the formation of the groove 46. ) 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.

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

Note that the groove 46 is formed by such press working.
Is formed, the processing conditions are not particularly limited, and are appropriately determined according to the conditions such as the material, the inner diameter, and the thickness of the inner needle 4. Usually, the pressing pressure is about 50 to 300 kg / cm ^2. More preferably, it is about 100 to 300 kg / cm ² .

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, the grooves 46 can be formed in the plurality of inner needles 4 at one time, and the 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 for 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.

FIG. 17 is a longitudinal sectional view showing the structure near the distal end in an assembled state according to another embodiment of the indwelling needle assembly of the present invention, and FIG. 18 is a sectional view taken along line GG in FIG. is there. Hereinafter, the embodiment shown in FIGS.
The following mainly describes differences from the embodiment shown in FIGS.

In this indwelling needle assembly, the inner needle 4 is a normal one in which the chamfered portion 43, the rough surface 45 or the groove 46 is not formed. A plurality of grooves (voids) 2 extending in the longitudinal direction of the outer needle 2 are formed on the inner peripheral surface of the reduced diameter portion 21 of the outer needle 2.
4, four grooves 24 at 90 ° intervals in the configuration shown
Are formed (see FIG. 18).

Although the depth f of the groove 24 is not particularly limited,
Usually, about 0.01 to 0.5 mm is preferable, and 0.03 to
It is more preferably about 0.2 mm.

The indwelling needle assembly having such a configuration in which the outer needle 2 has the groove 24 is also used in the same manner as in the above embodiment. In this case, in step [2], when the distal end of the outer needle 2 is inserted into the blood vessel, blood flows through the distal end opening 23, passes through each groove 24, and then turns the gap 22 in the proximal direction. And flows 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.

The greatest advantage of providing the groove 24 serving as a blood flow path on the outer needle 2 side is that the processing and formation are easy. The details will be described below.

The outer needle 2 is a tubular member, and since the constituent material is a resin material as described above, it can be manufactured by extrusion molding. According to this molding method, the groove 24 can be formed at the same time when the outer needle 2 is molded, and there is no additional manufacturing process. In particular, the shape, dimensions, arrangement pattern, and the like of the grooves 24 can be arbitrarily set depending on the shape of the die (the die portion from which the molten resin comes out) of the extruder.

The formation of the groove 24 on the outer needle 2 is easier than forming the inner needle 4 made of metal.

It is needless to say that various conditions relating to the groove 24, such as the shape, dimensions, arrangement pattern, and forming method of the groove 24, are not limited to those described above.

Although the indwelling needle assembly according to 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.

Also, the chamfered portion 43, the rough surface 45,
The groove 46, the groove 24 and the like may be formed at a portion other than the close contact portion between the outer needle 2 and the inner needle 4, and may be formed over substantially the entire length of the outer needle 2 or the inner needle 4, for example.

[0107]

As described above, according to the indwelling needle assembly of the present invention, the groove formed on the outer peripheral surface of the inner needle by chamfering, roughening, plastic deformation, and the like, and the inner peripheral surface of the outer needle are formed. Since the blood flow path is formed by the gap formed in the surface, it can be confirmed by flashback of the blood that the outer needle has secured the blood vessel. Therefore, the puncture operation of the indwelling needle into the blood vessel can be performed easily and accurately.

In addition, the indwelling needle assembly of the present invention can be manufactured,
Processing is easy and processing accuracy is high. In particular, when a plurality of inner needles are processed at the same time, or when the outer needles are manufactured by extrusion molding, the production efficiency is high, and there is no increase in the number of manufacturing steps.

Further, according to the method for manufacturing an inner needle of the present invention,
With a simple operation, a groove can be formed at an appropriate position in an appropriate shape.

In particular, when the thickness of the tube of the inner needle is made substantially constant over the entire circumference including the portion where the groove is formed, it is possible to prevent a decrease in the strength of the portion where the groove is formed.

[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 vertical cross-sectional view showing a configuration near a distal end portion in an assembled state.

FIG. 6 is a perspective view showing a configuration of a tip portion of an inner needle according to another embodiment of the indwelling needle assembly of the present invention.

FIG. 7 is a vertical cross-sectional view showing a configuration near a tip end in an assembled state.

FIG. 8 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. 9 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.

FIG. 10 is a sectional view taken along line CC in FIG. 9;

FIG. 11 is a sectional view taken along line DD in FIG. 9;

FIG. 12 is a vertical cross-sectional view showing a configuration near a distal end portion in an assembled state.

FIG. 13 is a perspective view showing an example of a method for manufacturing an inner needle.

14 is a sectional view taken along line EE in FIG.

FIG. 15 is a cross-sectional view (before pressing) taken along line FF in FIG. 13;

FIG. 16 is a cross-sectional view taken after the FF line in FIG. 13 (after pressing).

FIG. 17 is a longitudinal sectional view showing a configuration near the distal end portion in an assembled state according to another embodiment of the indwelling needle assembly of the present invention.

18 is a sectional view taken along line GG in FIG.

[Explanation of symbols]

 Reference Signs List 1 indwelling needle assembly 2 outer needle (indwelling needle) 21 reduced diameter portion 22 gap 23 tip opening 24 groove 3 hub 31 inside 4 inner needle 41 needle point 42 blade surface 43 chamfered portion 44 gap 45 rough surface 46 groove 47 edge portion 48 Projecting part 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 (17)

[Claims] 1. An indwelling needle assembly comprising a hollow outer needle and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, characterized in that at least a portion of the outer peripheral portion that is in close contact with the outer needle is chamfered. 2. An indwelling needle assembly comprising: a hollow outer needle; and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, characterized in that the indwelling needle assembly has a portion on an outer peripheral portion thereof, which is chamfered from near a root of the blade surface along an axial direction of the inner needle. 3. An indwelling needle assembly comprising: a hollow outer needle; and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, characterized in that at least a portion of the outer peripheral portion that is in close contact with the outer needle is roughened. 4. An indwelling needle assembly comprising a hollow outer needle and an inner needle inserted into a lumen of the outer needle and having an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, characterized in that the outer peripheral portion has a portion that is roughened along the axial direction of the inner needle from near the root of the blade surface. 5. An indwelling needle assembly comprising a hollow outer needle and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, characterized in that a groove formed by plastically deforming the inner needle is provided at least in a portion in close contact with the outer needle. 6. An indwelling needle assembly comprising: a hollow outer needle; and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. And an indwelling needle assembly provided with a groove formed by plastically deforming the inner needle from near the root of the blade surface along the axial direction of the inner needle. 7. An indwelling needle assembly comprising a hollow outer needle and an inner needle which is inserted into a lumen of the outer needle and has an inclined blade surface at a needle tip thereof, wherein An indwelling needle assembly, wherein a groove is provided at least in a portion in close contact with the outer needle, and a wall thickness of the tube of the inner needle is substantially constant over an entire circumference including a portion where the groove is formed. 8. An indwelling needle assembly comprising: a hollow outer needle; and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. A groove is provided along the axial direction of the inner needle from near the root of the blade surface, and the thickness of the tube of the inner needle is substantially constant over the entire circumference including the portion where the groove is formed. A unique indwelling needle assembly. 9. The indwelling needle assembly according to claim 7, wherein the groove is formed by plastically deforming the inner needle. 10. The indwelling needle assembly according to claim 5, wherein the plastic deformation is performed by press working. 11. The indwelling needle assembly according to claim 5, wherein the vicinity of a boundary between the groove and the outer peripheral surface of the inner needle is rounded. 12. An indwelling needle assembly comprising: a hollow outer needle; and an inner needle that is inserted into a lumen of the outer needle and has an inclined blade surface at the tip of the outer needle. An indwelling needle assembly, wherein a void serving as a blood flow path is formed in at least a portion of the inner peripheral portion that is in close contact with the inner needle. 13. An indwelling needle assembly comprising a hollow outer needle and an inner needle inserted into a lumen of the outer needle and having an inclined blade surface at the tip of the outer needle. The distal end portion has a reduced diameter portion whose inner diameter is reduced and closely adheres to the inner needle, and a void serving as a blood flow path is formed on an inner peripheral surface of the reduced diameter portion. Indwelling needle assembly. 14. A method for producing an inner needle which is used by being inserted into a lumen of a hollow outer needle and has an inclined blade surface at the needle tip, wherein the step of forming the blade surface; Forming a groove by plastic working at least in a portion in close contact with the outer needle. 15. A method for manufacturing an inner needle which is used by being inserted into a lumen of a hollow outer needle and has an inclined blade surface at the needle tip, wherein the step of forming the blade surface; Along the axial direction of the inner needle from near the root of
Forming a groove by plastic working. 16. The inner groove according to claim 14, wherein the groove is formed such that the wall thickness of the tube of the inner needle is substantially constant over the entire circumference including a portion where the groove is formed. Needle manufacturing method. 17. The method according to claim 14, wherein the formation of the groove is performed while positioning with reference to the position of the blade surface.
7. The method for producing an inner needle according to any one of 6.