US 5,644,177 A · Micromechanical magnetically actuated devices

Abstract

Micromechanical structures capable of actuation for purposes such as fluid flow control are formed on substrates in sizes in the range of one or two millimeters or less using micromechanical processing techniques. A magnetic core having a gap therein is fixed on the substrate, and a plunger is mounted by a spring for movement parallel to the substrate in response to the flux provided to the gap of the fixed core. An electrical coil wound around a mandrel is engaged to the fixed magnetic core such that flux is induced in the core when current is supplied to the coil, driving the plunger against the force of the spring. A micromechanical fluid control unit includes a metal frame structure formed by electrodeposition on a substrate with the inner wall of the frame having slots formed therein to admit a separator wall which divides the interior of the frame into separate chambers, with a cover secured over the top of the frame and the separator wall to seal the chambers. A plunger actuator can be mounted within the frame with fixed core sections extending through the walls of the frame, and with the mandrel and coil engaged to the fixed core sections outside of the frame to provide magnetic flux to a gap to actuate the plunger within the sealed enclosure.

Claims30

Dependent claims

A micromechanical linear actuator comprising:

(a) a nonferromagnetic substrate having a top surface;
(b) a fixed magnetic core on the substrate top surface, the magnetic core having end faces spaced apart to define a gap in the core, the core formed by electrodeposition of a ferromagnetic material onto the surface of the substrate;
(c) a plunger having a magnetic head, at least the head of the plunger formed of a magnetic material;
(d) means for supporting the plunger for linear movement such that the head of the plunger can move toward and away from the gap in the fixed core;
and
(e) a coil of electrical conductor coupled to the fixed magnetic core to provide magnetic flux therethrough when the coil is supplied with electrical current such that the head of the plunger is magnetically actuated when the coil is supplied with current, wherein the coil is wound around a mandrel formed of ferromagnetic material, the mandrel having end sections on either side of the coil, the end sections of the mandrel and the fixed core having mating structures which are engaged together to mount the mandrel and coil to the fixed core to complete a magnetic flux circuit through the mandrel, the fixed core, and the gap in the fixed core.

3 more elements

A micromechanical fluid control unit comprising:

(a) a substrate having a substantially planar top surface;
(b) a metal frame formed by electrodeposition on the top surface of the substrate, the frame formed by a frame wall which surrounds a central cavity, the frame wall having at least two opposed inner wall surfaces having slots formed therein which extend perpendicular to the substrate;
(c) a separator wall sized to fit into the slots in the opposed inner wall faces of the frame to divide the interior cavity within the frame into at least two chambers, the separator wall having at least one opening therein to provide controlled communication between the two chambers in the frame, the frame and the separator wall each having a top surface which is substantially flat and at the same level;
and
(d) a top cover formed of metal secured over the top of the frame and the separator wall to seal the cavity within the frame from the exterior ambient and to seal the chambers formed within the frame from one another.

2 more elements

Dependencies are inferred from the claim text.

Micromechanical magnetically actuated devices

Life of this patent

Micromechanical magnetically actuated devices

Life of this patent

Abstract

Claims30