Method of making a hollow lumen cable

• US 5,373,619 A
• Filed: 09/14/1992
• Issued: 12/20/1994
• Est. Priority Date: 09/30/1987
• Status: Expired due to Term

• Current Assignee: Lake Region Manufacturing Incorporated (Integer Holdings Corporation Inc)
• Original Assignee: Lake Region Manufacturing Incorporated (Integer Holdings Corporation Inc)
• Inventors: Fleischhacker, Mark G., Fleischhacker, Joseph F. Jr., Hanson, Donald W., Hargreaves, Thomas E.
• Primary Examiner(s): Rosenbaum, Mark
• Assistant Examiner(s): Bryant, David P.
• Application Number:
  US07/944,501
• Time in Patent Office: 827 Days
• Field of Search: 29/450, 29/435, 29/451, 128/656, 128/657, 128/658, 128/772, 604/264, 604/282
• US Class Current: 29/451
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 17/32002 with continuously rotating, oscillating or reciprocating cutting instruments
• CPC Class Codes: A61B 17/3207 Atherectomy devices working by cutting or abrading; Similar devices specially adapted for non-vascular obstructions A61B17/32037 takes precedence; endoscopic cutting instruments A61B17/320016
• CPC Class Codes: A61B 18/245 for removing obstructions in blood vessels or calculi
• CPC Class Codes: A61M 2025/09066 having a coil without a core possibly combined with a sheath
• CPC Class Codes: A61M 2025/09091 where a sheath surrounds the coil at the distal part
• CPC Class Codes: A61M 2025/09191 made of twisted wires
• CPC Class Codes: A61M 25/0105 Steering means as part of the catheter or advancing means; Markers for positioning systems for detection of markers A61B
• CPC Class Codes: A61M 25/09 Guide wires
• CPC Class Codes: Y10T 29/4987 Elastic joining of parts
• CPC Class Codes: Y10T 29/49872 Confining elastic part in socket

Abstract

A hollow lumen cable is formed by helically winding inner and outer coils with the helices of each coil being in an abutting relationship and the outer coil inner diameter being less than the outer, peripheral, diameter of the inner coil. Preferably, each coil is multifilar. After the coils are wound, an unwinding force is applied to the outer coil and the inner coil is inserted into the outer coil to have its winding inclined opposite to that of the outer coil; and thence, the outer coil is allowed to contract to form an interference fit with the inner coil. The cable may be incorporated as part of various medical systems e.g., implantable pumps or other rotatable medical apparatuses. The cable is bendable about the tight radii, has a high torque transfer, a small outer diameter, and a hollow lumen through which fluid, wires or medical devices may pass.

Claims

1. A process for making a cable adapted for medical usage, comprising helically winding wires into inner and outer coils with the outer coil in its relaxed non-assembled condition to have an outer coil inner diameter and an outer diameter for use in a vascular vessel and the inner coil in its relaxed non-assembled condition to have a hollow lumen and an inner coil outer diameter that is larger than the outer coil inner diameter and the adjacent helices of the respective coils in contact with one another, applying an unwinding force to the outer coil to partially unwind the outer coil to have an inner diameter larger than the outer diameter of the inner coil, relatively moving the inner coil and the thus partially unwound outer coil to have the inner coil surrounded by the outer coil and its convolutions wound in the opposite direction from that of the outer coil, and removing the unwinding force from the outer coil to allow the outer coil to form an interference fit with the inner coil, the coils being wound to have distal and proximal ends and to provide a substantially 1 to 1 transfer of torque from the proximal ends of the coils to their distal ends, regardless of the direction of rotation of the coils after they are in interference fitting relationship.

2. The process of claim 1 wherein the inner coil in the interference fitting relationship is throughout at least substantially its entire length free of interior structure.

3. The process of claim 1 wherein each coil has a central axis and wherein the winding of each coil includes winding a plurality of wires about its central axis such that each wire is about the same radial spacing from the respective axis and such that each convolution of each wire for the respective coil is axially between adjacent convolutions of another wire of the same coil, and cleaning each coil prior to applying the unwinding force.

4. The process of claim 1 wherein the coils in their interference fitting relationship have axially spaced end portions, the process further comprising the steps of joining connectors to the coil end portions and connecting one of the connectors to a prime mover and connecting the other connector to a medical pump to place the medical pump in driven relationship with respect to the prime mover.

5. The process of claim 1 further comprising prior to unwinding the outer coil, the steps of partially unwinding the inner coil, inserting a guide wire core wire into the partially unwound inner coil, the inner diameter of the inner coil in its relaxed condition being less than the diameter of at least a major portion of the axial length of the core wire after insertion of the core wire, and allowing the inner coil to contract to form an interference fit with the core wire whereby a steerable guide wire is formed.

6. The process of claim 1 further comprising providing a guide wire main wire having a distal end, a proximal end, and an axially elongated cylinder portion extending axially between the main wire ends, the inner coil inner diameter in the inner coil relaxed condition being less than the diameter of the cylinder portion, and prior to moving the inner coil to have the inner coil surrounded by the outer coil, partially unwinding the inner coil to have the inner coil inner diameter larger than the diameter of the cylinder portion, inserting the cylinder portion into the inner coil, allowing the partially unwound inner coil to Contract to form a press fit with the cylinder portion and after allowing the outer coil form an interference fit with the inner coil, providing a guide wire distal tip joined to the main wire distal end and the distal end of at least the outer coil.

7. The process of claim 1 wherein the coils in their interference fitting relationship have a proximal end portion and a distal end portion, further comprising attaching a medical subassembly to their proximal end portion.

8. The process of claim 7 wherein the medical subassembly includes a connector and an operable medical device mounted upon and movable relative to the connector, further comprising:

in indifferent order, mounting a finger grip member to the proximal end portion of the coils, mounting the connector to the distal end portion of the coils and inserting a core member through the inner coil and connecting the core member to a manipulator member and the medical device whereby the medical device is operable by moving the manipulator relative to the finger grip member.

9. The process of claim 1 wherein the outer coil and inner coil in their assembled relationship have a distal and a proximal end portion and respectively have radial outer and radial inner coil portions, and further comprising providing a tubular plastic coating to at least one of the outer coil portion to extend radially outwardly therefrom or the inner coil portion to extend radially inwardly thereof substantially the axial length of the coils.

10. The process of claim 9 wherein a catheter is fixed to the proximal end portion of the assembled coils to form a catheter assembly and wherein the plastic coating extends axially further from the assembly than the proximal end portion of the assembled coils.

11. The process of claim 9 wherein the plastic coating step comprises joining a radially inner plastic tubular portion within the inner coil that extends substantially the entire length of the inner coil and the plastic inner tubular portion having a generally smooth, circumferential surface throughout substantially its entire length, and joining a luer fitting to the proximal end portion of the assembled coils to form a catheter.

12. The process of claim 9 wherein the plastic coating step comprises providing a radially outer plastic tubular portion on the outer coil to extend radially outwardly thereof and substantially the length of the outer coil to have a generally smooth, circumferential outer surface, and joining a luer fitting to the proximal end portion of the assembled coils to form a catheter.

13. A process for making a medical apparatus, comprising helically winding a first coil to have adjacent helices in abutting relationship and a given inner peripheral diameter and a given outer diameter in a relaxed non-assembled condition, helically winding a second coil to have adjacent helices in abutting relationship, an outer peripheral diameter of a maximum of about 1/16" and an inner peripheral diameter that is less than the first coil outer peripheral diameter in a relaxed non-assembled condition, each winding step including winding the coils to have distal and proximal end portions, applying an unwinding force to the second coil to increase the second coil non-assembled inner diameter, moving the first coil into the second coil while the unwinding force is being applied to the second coil with the coils wound in opposite directions, and thereafter removing the unwinding force to allow the second coil to form an interference fit with the inner coil to form a hollow lumen cable having a distal end portion and a proximal end portion, the coils being wound and in interference relationship to provide a substantially 1 to 1 transfer of torque from the proximal end portion to the distal end portion, regardless of the direction of rotation of the cable.

14. The process of claim 13 further comprising mounting a first connector on the cable proximal end portion, mounting a second connector on the cable distal end portion, connecting the first connector to a prime mover for being rotated thereby, and connecting the second connector to a blood pump for driving the blood pump.

15. The process of claim 13 wherein the outer and inner coils have distal and proximal ends and have radially outer and inner coil portions respectively, the process further comprising providing a plastic tubular portion to at least one of the outer and inner coil portions to extend radially outwardly and radially inwardly of the respective outer and inner coil portions and attaching a luer fitting to the proximal ends of the coils to form a catheter.

16. The process of claim 13 further comprising mounting a manually operated control member on the cable proximal end portion and a medical subassembly on the cable distal end portion.

17. The process of claim 16 wherein the control member includes a hand grip portion and a manipulator portion movably mounted to the hand grip portion, and the medical subassembly includes a mounting part and an operable part mounted for movement thereon.

18. The process of claim 17 wherein each of the coils is multi-filar.

19. The process of claim 17 further characterized in that the operable part is a body tissue scraper part.

20. A process for making a guide wire, comprising helically winding wire into respective inner and outer coils with adjacent helices in contact with one another, the outer coil in its relaxed, non-assembled condition having an inner diameter that is smaller than the inner coil outer diameter and an outer diameter for use in a vascular vessel, and the inner coil in its relaxed, non-assembled condition having a hollow lumen, opposite ends and an inner coil outer diameter that is larger than the outer coil inner diameter applying a force to the outer coil to partially unwind the outer coil to have an inner diameter larger than the outer diameter of the inner coil;

relatively moving the inner coil and the thus partially unwound outer coil to have the inner coil surrounded by the outer coil and its convolutions wound in the opposite direction from that of the outer coil; and

removing the unwinding force from the outer coil to allow the outer coil to contract to form an interference fit with the inner coil;

inserting an axially elongated guide wire main wire having a distal end into the inner coil; and

joining the main wire distal end to at least one of the outer coil or the inner coil.

21. The process of claim 20, the main wire having a proximal cylindrical port, an intermediate portion joined to the cylindrical portion, and a distal end portion that is joined to the intermediate portion and to the inner and outer coil distal portions, the process further including joining the proximal ends of the inner, and outer coils to the guide wire main wire adjacent to the juncture of the main wire cylindrical and intermediate portions.

22. The process of claim 21, in which the main wire intermediate portion includes a frustoconical part having a major base integrally joined to the cylindrical portion and a minor base Joined to the main wire distal portion.

23. The process of claim 20 wherein the main wire is of a maximum diameter that is substantially smaller than the inner coil inner diameter, each of the coils has a distal end portion and a proximal end portion, and the process further comprises securing the proximal end portions of the coils to the main wire, and joining the guide wire distal end to the distal end portions of the coils.

24. A process for making a medical apparatus, comprising helically winding a first coil to have adjacent helices in abutting relationship and of a given inner peripheral diameter and a given outer diameter in a relaxed non-assembled condition, helically winding a second coil to have adjacent helices in abutting relationship, an outer peripheral diameter of a maximum of about 1/16 inch and an inner peripheral diameter that is less than the first coil outer peripheral diameter in a relaxed non-assembled condition, the winding step including winding the coils to have distal and proximal end portions, applying an unwinding force to the second coil to increase the second coil non-assembled inner diameter, moving the first coil into the second coil while the unwinding force is being applied to the second coil with the coils wound in opposite directions, and thereafter removing the unwinding force to allow the second coil to form an interference fit with the first coil to form a hollow lumen cable having a distal end portion and a proximal end portion.

25. A process for making a steerable guidewire comprising the steps of:

helically winding wires into respective inner and outer coils with proximal and distal ends and with adjacent helices in contact with one another, the outer coil in its relaxed non-assembled condition to have an outer coal inner diameter and an outer diameter for use in a vascular vessel and the inner coil in its relaxed non-assembled condition to have a hollow lumen and an inner coil outer diameter that is larger than the outer coil inner diameter;

partially unwinding the inner coil;

inserting a guide ware core wire into the partially unwound inner coil, the inner diameter of the inner coil in its relaxed condition being less than the diameter of at least a major portion of the axial length of the core wire;

allowing the inner coil to contract to form an interference fit with the core wire;

applying an unwinding force to the outer coil to partially unwind the outer coil to have an inner diameter larger than the outer diameter of the inner coil;

relatively moving the inner coil and the thus partially unwound outer coil to have the inner coil surrounded by the outer coil and its convolutions wound An the opposite direction from that of the outer coil, and removing the unwinding force from the outer coil to allow the outer coil to contract to form an interference fit with the inner coil to provide a substantially 1 to 1 transfer of torque from the proximal ends of the coils to their distal ends, regardless of the direction of rotation of the coils after they are in interference fitting relationship.