Catheter having shaft accommodation portion that accommodates and is fused to elongated shaft

A catheter comprising:

• an elongated shaft extending from a distal end of the elongated shaft to a proximal end of the elongated shaft so that the proximal end of the elongated shaft is on a proximal side of the distal end of the elongated shaft, the elongated shaft including a lumen extending along the elongated shaft and opening to the proximal end of the shaft at a shaft proximal opening while also opening to the distal end of the shaft, the elongated shaft including a shaft proximal end surface at the proximal end of the elongated shaft, the elongated shaft also including a shaft outer surface that faces radially outwardly, extends continuously in a proximal direction from the distal end of the elongated shaft to the proximal end of the elongated shaft and terminates at the shaft proximal end surface, the elongated shaft including a shaft inner surface that surrounds the lumen, extends continuously in the proximal direction from the distal end of the elongated shaft to the proximal end of the elongated shaft and terminates at the shaft proximal end surface, an entirety of the shaft inner surface being radially inwardly of the shaft outer surface;
• a hub that includes a shaft accommodation portion in which is accommodated a proximal portion of the elongated shaft, the shaft accommodation portion possessing an inner diameter, the hub also including a hub lumen extending from a hub proximal opening at a proximal end of the hub toward a distal end of the hub, the hub lumen communicating with the shaft accommodation portion, the hub also including a hub distal opening at the distal end of the hub that communicates with the shaft accommodation portion of the hub;
• the shaft outer surface of the proximal portion of the elongated shaft and an inner surface of the shaft accommodation portion being directly fusion-bonded to each other along a portion of the elongated shaft, without an adhesive interposed between the elongated shaft and the hub, to form a longitudinally extending fusion surface;
• a proximal portion of the shaft accommodation portion of the hub including an adjacent surface that faces toward the shaft proximal end surface of the elongated shaft;
• the radially outwardly facing shaft outer surface of the elongated shaft that extends continuously from the distal end of the elongated shaft to the proximal end of the elongated shaft including a portion that is spaced from the inner surface of the shaft accommodation portion so that a gap exists between the portion of the shaft outer surface of the elongated shaft and the inner surface of the shaft accommodation portion, the portion of the shaft outer surface of the elongated shaft being on the proximal side of the fusion surface;
• and
• the fusion surface possessing an inner diameter that is a smaller than the inner diameter of all other portions of the shaft accommodation portion of the hub positioned proximally and distally of the fusion surface.

A catheter comprising:

• a shaft that is elongated and extends from a distal end of the shaft to a proximal end of the shaft, the shaft having a lumen extending throughout the shaft, the shaft having an inner surface that surrounds the lumen, that faces radially inwardly and that extends continuously in a proximal direction from the distal end of the shaft to the proximal end of the shaft;
• the shaft including a shaft proximal end surface and a shaft proximal opening that is a proximal end of the lumen in the shaft, the shaft proximal end surface facing away from the distal end of the shaft, and the shaft also having a shaft outer surface extending continuously from the distal end of the shaft to the proximal end of the shaft, an entirety of the shaft outer surface being radially outwardly of the inner surface of the shaft;
• a hub attached to the proximal end of the shaft, the hub including a distal end and a proximal end;
• the hub including a hub distal opening at the distal end of the hub, a shaft accommodation portion in which is accommodated the proximal end of the shaft, and a hub proximal opening at the proximal end of the hub, the shaft accommodation portion extending from a proximal end of the shaft accommodation portion to a distal end of the shaft accommodation portion so that the proximal end of the shaft accommodation portion is on a proximal side of the distal end of the shaft accommodation portion and so that the distal end of the shaft accommodation portion is on a distal side of the proximal end of the shaft accommodation portion;
• the shaft accommodation portion of the hub including an adjacent surface that is at the proximal end of the shaft accommodation portion and that faces towards the distal end of the hub, the adjacent surface of the shaft accommodation portion facing the shaft proximal end surface of the shaft, the shaft accommodation portion having a radially inwardly facing inner surface that extends continuously from the distal end of the shaft accommodation portion toward the proximal end of the shaft accommodation portion and that terminates at the adjacent surface of the shaft accommodation portion;
• the adjacent surface of the shaft accommodation portion including a hole that communicates with the hub proximal opening and that is positioned adjacent the shaft proximal opening;
• a proximal portion of the shaft outer surface being directly fusion-bonded to the hub along the shaft longitudinal axis to form a fusion surface that extends along the shaft longitudinal axis;
• the radially inwardly facing inner surface of the shaft accommodation portion including a part located on the proximal side of the fusion surface, the radially outwardly facing shaft outer surface of the shaft that extends continuously from the distal end of the shaft to the proximal end of the shaft including a part located on the proximal side of the fusion surface;
• the part of the radially inwardly facing inner surface of the shaft accommodation portion and the part of the radially outwardly facing shaft outer surface of the shaft facing one another and being spaced from one another so that a radial gap exists between the part of the radially inwardly facing inner surface of the shaft accommodation portion and the part of the radially outwardly facing shaft outer surface of the shaft, the radial gap being on the proximal side of the fusion surface and on the distal side of the adjacent surface of the shaft accommodation portion of the hub;
• and
• an inner diameter of the hub distal opening being larger than an inner diameter of the adjacent surface of the shaft accommodation portion, an inner diameter of the shaft accommodation portion being smallest, along its entire longitudinal extent, at the fusion surface.