Search

CN-121987927-A - Guide wire

CN121987927ACN 121987927 ACN121987927 ACN 121987927ACN-121987927-A

Abstract

The invention provides a guide wire which does not generate a gap between a resin sleeve and a rear end side coil all the time, and has good insertability when being inserted into a bent blood vessel and good matching with a combined device. The guide wire is provided with a core wire (10), a resin sleeve (20), a front end side coil (30), a rear end side coil (40) and an inner side coil (50), wherein the front end side coil (30) is fixed to a distal end side small diameter part (11) of the core wire (10) at a front end part (31) and a rear end part (32) thereof through brazing filler metals (61, 62), respectively, the rear end side coil (40) is provided with a brazing filler metal impregnated rear end part (42) and a brazing filler metal non-impregnated front end part (41), and a brazing filler metal (63) for fixing the rear end side coil (40) to the distal end side small diameter part (11) of the core wire (10) is impregnated into the brazing filler metal impregnated rear end part (42) and is not impregnated into the brazing filler metal non-impregnated front end part (41).

Inventors

  • Ji Deguchi
  • KAWASAKI HIRONORI

Assignees

  • 株式会社FMD

Dates

Publication Date
20260508
Application Date
20251103
Priority Date
20241105

Claims (7)

  1. 1. A guide wire, wherein, The guide wire is provided with: a core wire (10); a resin sleeve (20) rotatably disposed around the distal small diameter portion (11) of the core wire (10); A distal end side coil (30) which is configured by a compression coil spring having substantially the same outer diameter as the resin sleeve (20), is disposed on the distal end side of the resin sleeve (20) so as to surround the distal end side small diameter portion (11) of the core wire (10), and the rear end thereof is in contact with the distal end surface of the resin sleeve (20), and A rear end side coil (40) which is configured by a compression coil spring having substantially the same outer diameter as the resin sleeve (20), is arranged on the rear end side of the resin sleeve (20) so as to surround the distal end side small diameter portion (11) of the core wire (10), and the front end thereof is in contact with the rear end surface of the resin sleeve (20), The front end side coil (30) is fixed to the distal end side small diameter portion (11) of the core wire (10) at a front end portion (31) and a rear end portion (32) thereof by brazing filler metals (61, 62), respectively, The rear end side coil (40) has a solder-impregnated rear end portion (42) and a solder-non-impregnated front end portion (41), and a solder (63) for fixing the rear end side coil (40) to the distal end side small diameter portion (11) of the core wire (10) is impregnated into the solder-impregnated rear end portion (42) and is not impregnated into the solder-non-impregnated front end portion (41).
  2. 2. The guidewire of claim 1, wherein, The coil outer diameter (D 40 ) of the rear end side coil (40) is 0.24-0.46 mm, the length (L 41 ) of the solder non-penetrating front end part (41) is 0.4-1.6 mm, and the length (L 42 ) of the solder penetrating rear end part (42) is 0.4-1.6 mm.
  3. 3. The guidewire of claim 2, wherein, In the compression coil spring constituting the rear end side coil (40), when the free length of a portion to be the solder non-penetration front end portion (41) is L o and the tightening length of the portion is Ls, the length (L 41 ) of the solder non-penetration front end portion (41) satisfies the following formula, The formula (ls+0.05mm) is less than or equal to L 41 ≤（L o -0.1 mm.
  4. 4. The guidewire of claim 1, wherein, The guide wire is provided with an inner coil (50) formed by a compression coil spring, The inner coil (50) has: A distal end portion (51) fixed to the distal end small diameter portion (11) of the core wire (10) together with the distal end portion (31) of the distal end side coil (30), and And a rear end portion (52) fixed to the distal small diameter portion (11) of the core wire (10) by a brazing filler metal (64) in the resin sleeve (20).
  5. 5. The guidewire according to any one of claims 1 to 4, wherein, The resin sleeve (20) has a double-layer structure of an inner layer (21) made of polyimide and an outer layer (22) made of polyether block polyamide.
  6. 6. The guidewire according to any one of claims 1 to 4, wherein, A rearmost portion (322) of the rear end portion (32) of the front end side coil (30) is a solder non-impregnated portion in which solder is not impregnated.
  7. 7. The guidewire according to any one of claims 1 to 4, wherein, The rear end of the front end side coil and the front end of the rear end side coil are formed as closed ends.

Description

Guide wire Technical Field The present invention relates to a guide wire used when a medical device is inserted into a living body. Background Conventionally, as a medical guidewire having a small resistance and good straightness, a guidewire in which a resin sleeve is disposed at a distal small diameter portion of a core wire has been proposed (see patent document 1 below). The guide wire described in this document includes a core wire, a sleeve made of polyimide disposed at a small diameter portion of the core wire at a distal end side thereof, and a tip coil and a rear coil disposed at the small diameter portion of the core wire at the distal end side thereof so as to sandwich the sleeve. The sleeve constituting the guide wire is rotatably disposed around the distal small diameter portion of the core wire, and thus has excellent torque transmissibility (paragraph 0024 of this document). Prior art literature Patent literature Patent document 1 Japanese patent application No. 4994381 Disclosure of Invention Problems to be solved by the invention In the case of manufacturing a guide wire as described in patent document 1, there is a problem in that the rear end portion of the sleeve is melted by heat of the brazing material used in the step of fixing (brazing) the rear end side coil to the distal end side small diameter portion of the core wire. In order to avoid this problem, it is necessary to braze the rear end side coil at a position separated from the rear end of the sleeve by a certain distance. Therefore, in the guide wire actually manufactured, the tip end of the rear end side coil cannot be brought into contact with the rear end surface of the sleeve, and as shown in fig. 12, a gap G (a step between the sleeve and the core wire, a step between the rear end side coil and the core wire) is inevitably formed between the sleeve and the rear end side coil. When such a gap is formed, insertion resistance increases when the guide wire is inserted into a curved blood vessel or the like, or a step portion due to the gap comes into contact with plaque in the blood vessel, and thus insertability is impaired. In addition, the gap (step) also deteriorates the compatibility with a catheter or the like and a device used in combination. When the guide wire is bent by insertion into a bent blood vessel or the like, the sleeve is slightly moved in the distal end direction with respect to the core wire, and the rear end surface of the sleeve is displaced in the same direction, whereby the gap (the separation distance between the rear end surface of the sleeve and the distal end of the rear end side coil) tends to be enlarged as compared with before bending. The present invention has been made in view of the above circumstances, and an object thereof is to provide a guide wire which does not generate a gap between a sleeve and a rear end side coil, has excellent insertion into a curved blood vessel and compatibility with a combined device, and is free from melting of a rear end portion of a resin sleeve due to heat during brazing at the time of manufacturing (brazing step of a rear end side coil). Means for solving the problems (1) The guide wire of the present invention is characterized by comprising a core wire, a resin sleeve rotatably disposed around a distal small diameter portion of the core wire, a front end coil composed of a compression coil spring having substantially the same outer diameter as the resin sleeve and disposed on a front end side of the resin sleeve so as to surround the distal small diameter portion of the core wire, a rear end coil composed of a compression coil spring having substantially the same outer diameter as the resin sleeve and disposed on a rear end side of the resin sleeve so as to surround the distal small diameter portion of the core wire, a front end coil having a solder-impregnated rear end portion and a solder-non-impregnated front end portion, the front end coil being fixed to the distal small diameter portion of the core wire by solder, the rear end coil having a solder-impregnated rear end portion and a solder-non-impregnated front end portion, the solder-impregnated rear end coil being fixed to the distal small diameter portion of the core wire, the solder-non-impregnated front end portion being fixed to the solder-non-filled rear end portion of the core wire. According to the guide wire having such a structure, since the front end of the rear end side coil formed of the compression coil spring having substantially the same outer diameter as the resin sleeve is in contact with the rear end surface of the resin sleeve, a gap (step) is not generated between the resin sleeve and the rear end side coil. In addition, in the case of manufacturing the guide wire (the brazing step of the rear end side coil), the rear end side coil is brazed (the formation of the brazing filler metal-impregnated rear end portion) at a position separated from the rear end of the resin sleeve by a su