Multi-material single-piece actuator member for miniature reciprocating piston pump in medical applications
An implantable medical device including a two piece actuator member which comprises a monocrystaline piston and a magnetizable pole. The monocrystalline piston is positioned within a piston channel having a surface having a titanium-oxide layer. The monocrystalline piston is selectively movable within the piston bore to permit intake and output of fluids.
1. An implantable medical device, comprising:
a housing;
a reservoir disposed within the housing;
a drive mechanism assembly coupled to the housing, comprising:
a sleeve having a hollow piston channel, the surface of the channel including an oxidized layer and a lubricious layer disposed over the oxidized layer;
a two piece actuator member, the actuator member comprising:
a bio-compatible monocrystalline piston axially disposed within the piston channel bore; and
a magnetizable pole coupled to an end of the piston.
2. The device of claim 1 , wherein the bio-compatible monocrystalline is sapphire.
3. The device of claim 1 , wherein the bio-compatible monocrystalline is ruby.
4. The device of claim 1 , further comprising a lubricious layer disposed over the oxidized layer.
5. The device of claim 1 , wherein the piston is coupled to the pole through press fit coupling.
6. The device of claim 1 , wherein the piston is moveable within the piston channel upon magnetic attraction of the pole.
7. A pump assembly for delivery of an infusion medium, comprising:
a pump housing open on one side to a hollow interior section;
an actuator member sleeve disposed within the housing having a piston-receiving channel, wherein a surface of the channel comprises an oxidized layer and a lubricious layer disposed over the oxidized layer;
a two piece actuator member assembly including:
a bio-compatible monocrystalline piston axially disposed to reciprocate within the piston-receiving channel; and
a magnetizable pole coupled to the piston.
8. The pump assembly of claim 7 , wherein the pole is secured to the piston through press fit coupling in a perpendicular orientation.
9. The pump assembly of claim 7 , wherein the bio-compatible monocrystalline is sapphire.
10. The pump assembly of claim 7 , wherein the bio-compatible monocrystalline is ruby.
11. The pump assembly of claim 7 , wherein the bio-compatible monocrystalline piston is moveable within the piston-receiving channel upon magnetic attraction of the magnetizable pole to the sleeve.
12. The pump assembly of claim 7 , further comprising a cover coupled to the housing substantially adjacent the open side of the housing.