Ambulatory Infusion Devices And Piston Pumps For Use With Same

Abstract

An ambulatory infusion device including a fluid transfer device with a piston bore and a piston. The piston bore surface and the piston surface are configured such that they will wear at a very slow rate when cycled in the absence of a lubricant other than the infusible substance.

1 . An ambulatory infusion device, comprising:
 a reservoir; and   a fluid transfer device, operably connected to the reservoir, including   a housing having a piston bore defining a relatively soft piston bore surface, and   a relatively hard piston at least partially located within the piston bore.   
   
   
       2 . An ambulatory infusion device as claimed in  claim 1 , wherein the relatively soft piston bore surface comprises a titanium piston bore surface. 
   
   
       3 . An ambulatory infusion device as claimed in  claim 2 , wherein the titanium piston bore surface comprises an ASTM titanium grade 5 piston bore surface. 
   
   
       4 . An ambulatory infusion device as claimed in  claim 1 , wherein
 the relatively soft piston bore surface comprises a titanium piston bore surface; and   the relatively hard piston is selected from the group consisting of a hard ceramic piston, a hard crystalline piston, a glass piston, a vitreous carbon piston, and a hard graphite piston.   
   
   
       5 . An ambulatory infusion device as claimed in  claim 4 , wherein the relatively hard piston comprises a sapphire piston. 
   
   
       6 - 10 . (canceled) 
   
   
       11 . An ambulatory infusion device as claimed in  claim 1 , wherein the relatively soft piston bore surface comprises a metal piston bore surface and the relatively hard piston comprises a non-metal relatively hard piston. 
   
   
       12 . An ambulatory infusion device as claimed in  claim 1 , wherein the fluid transfer device includes an armature pole connected to the relatively hard piston and an electromagnet. 
   
   
       13 . An ambulatory infusion device as claimed in  claim 1 , wherein the fluid transfer device includes a bypass valve and a main check valve. 
   
   
       14 . An ambulatory infusion device as claimed in  claim 1 , further comprising:
 a device housing, including an outlet, that is sized, shaped and sealed in a manner suitable for implantation into a human body;   wherein the reservoir and fluid transfer device are located within the housing and the fluid transfer device is operably connected to the outlet.   
   
   
       15 . An ambulatory infusion device for supplying an infusible substance, comprising:
 a reservoir; and   a fluid transfer device, operably connected to the reservoir, including   a housing having a sleeve bore:   a sleeve, within the sleeve bore, formed from a different material than the housing, the sleeve having a piston bore defining a piston bore surface, and   a piston, at least partially located within the piston bore, defining a piston surface;   wherein the piston bore surface and the piston surface are formed from materials that wear at a slower rate than metal on metal when rubbed together repeatedly over many cycles.   
   
   
       16 . An ambulatory infusion device as claimed in  claim 15 , wherein the piston bore surface and the piston surface are formed from the same material. 
   
   
       17 . An ambulatory infusion device as claimed in  claim 15 , wherein the piston bore surface and the piston surface are formed from different materials. 
   
   
       18 . An ambulatory infusion device as claimed in  claim 15 , wherein the piston surface is a metal surface and the piston bore surface and the piston surface is a non-metal surface. 
   
   
       19 - 21 . (canceled) 
   
   
       22 . An ambulatory infusion device as claimed in  claim 15 , wherein
 the piston bore surface is formed from material selected from the group consisting of a hard ceramic material, a hard crystalline material, glass, titanium impregnated with nitrogen ions, vitreous carbon, and hard graphite; and   the piston surface is formed from material selected from the group consisting of a hard ceramic material, a hard crystalline material, glass, titanium impregnated with nitrogen ions, vitreous carbon, and hard graphite.   
   
   
       23 . An ambulatory infusion device as claimed in  claim 22 , wherein the piston surface is formed from sapphire and the piston bore surface is formed from sapphire. 
   
   
       24 . An ambulatory infusion device as claimed in  claim 22 , wherein the piston surface is formed from sapphire and the piston bore surface is formed from ruby. 
   
   
       25 . An ambulatory infusion device as claimed in  claim 15 , wherein
 the piston bore surface is formed from material selected from the group consisting of a hard ceramic material, a hard crystalline material, glass, titanium impregnated with nitrogen ions, vitreous carbon, and hard graphite; and   the piston surface is formed from titanium.   
   
   
       26 . An ambulatory infusion device as claimed in  claim 15 , wherein the fluid transfer device includes an armature pole connected to the piston and an electromagnet. 
   
   
       27 . An ambulatory infusion device as claimed in  claim 15 , wherein the fluid transfer device includes a bypass valve and a main check valve. 
   
   
       28 . An ambulatory infusion device as claimed in  claim 15 , further comprising:
 a device housing, including an outlet, that is sized, shaped and sealed in a manner suitable for implantation into a human body;   wherein the reservoir and fluid transfer device are located within the housing and the fluid transfer device is operably connected to the outlet.   
   
   
       29 . An ambulatory infusion device as claimed in  claim 15 , wherein the piston bore surface and the piston surface are formed from materials that wear at slower rate than metal on metal when rubbed together repeatedly over at least one million cycles.