Temperature responsive systems

• US 7,445,616 B2
• Filed: 03/17/2004
• Issued: 11/04/2008
• Est. Priority Date: 03/23/2001
• Status: Expired due to Term

• Current Assignee: Dennis N. Petrakis
• Original Assignee: Dennis N. Petrakis
• Inventors: Petrakis, Dennis N.
• Primary Examiner(s): SMITH, RICHARD A
• Application Number:
  US10/549,705
• Publication Number:
  US 20060260534A1
• Time in Patent Office: 1,693 Days
• Field of Search: 222/54, 222/541.2, 222/541.3, 222/541.4, 222/541.5, 222/541.6, 424/408, 424/452, 424/453, 424/454, 604/20, 604/21, 604/93.01, 604/131, 604/132, 604/134, 604/135, 60428801-28804, 604/304, 604/890.1, 604/891.1, 604/892.1, 128/DIG.12
• US Class Current: 604/890.1
• CPC Class Codes: G01K 1/02 Means for indicating or recording specially adapted for thermometers
• CPC Class Codes: G01K 5/483 using materials with a configuration memory, e.g. Ni-Ti alloys

Abstract

A shape memory material activated device of the present invention uses a shape memory material activator to create a path through a shell wall of the device. The path through the shell wall may release a substance contained in the shell or allow a substance to enter the shell. The path may be created by fracturing, puncturing, exploding, imploding, peeling, tearing, stretching, separating, debonding, abrading or otherwise opening the shell and, may be permanent or reversible. The substance may be released in one location while the device is stationary or along a path while it is traveling, self-powered by the shape memory material activator. In addition, the substance may be delivered to an object upon contact with its surface. The self powering abilities allow these devices to be used as substance delivery devices as well as actuators, transporters, and energy conversion systems with modular characteristics and growth potential. The devices may be armed, prior to the beginning of their service life, to be placed in a state of readiness to release their substances once the path is created. Prior to arming they may be maintained at any temperature, incapable of releasing their substances. The devices according to the present invention may be used as temperature sensors or warning devices, drug delivery devices, and the like.

Claims

1. A device for opening a shell to release or admit a substance, the device comprising:

a shell;

a shape memory material activator normally unresponsive to temperature changes thereby creating a dormant state; and

means for deforming the activator in situ by only a single irreversible action while the activator is within a predetermined temperature range,

whereby the device is transformed from the dormant state to an active state wherein the activator responds to temperature changes to create a path through the shell to release or admit the substance.

2. A method for opening a shell to release or admit a substance, the method comprising the steps of:

providing a shell;

providing a shape memory material activator normally unresponsive to temperature changes thereby creating a dormant state; and

deforming the activator in situ by only a single irreversible action while the activator is within a predetermined temperature range, whereby the device is transformed from the dormant state to an active state wherein the activator responds to temperature changes to create a path through the shell to release or admit the substance.

3. A self-propelled substance delivery system, comprising:

a shell containing at least a substance;

a shape memory material activator;

work enablers operatively associated with the activator; and

at least one track configured with fraction means, wherein the work enablers engage the traction means to self-propel the activator there along when the activator is subjected to temperature cycling and thereby deliver at least the substance.

4. A shape memory material activated device, the device comprising:

at least one shell containing at least a substance; and

a shape memory material activator variably deformed, wherein different parts of the activator respond to different temperatures, within a predetermined temperature range, to create a path through the at least one shell.

5. A shape memory material activated device for allowing the passing of a substance through a shell, the device comprising:

a shell having a volume for containing a substance;

a shape memory material activator; and

a pressure generator operatively associated with the shell and configured to undergo volume cycling with temperature cycling of the shape memory material activator,

whereby the substance passes through the shell with one half of the temperature cycle of the shape memory material activator and the shell undergoes an irreversible volume change with the other half of the temperature cycle.

6. A system of shape memory material activated substance delivery devices, the system comprising:

a plurality of stand alone shape memory material activated substance delivery devices, each device comprising at least one shell containing at least a substance and a shape memory material activator, said activator being normally unresponsive to temperature changes thereby creating a dormant state, means for deforming the activator in situ by only a single irreversible action while the activator is within a predetermined temperature range, wherein said activator is configured to release at least the substance at a predetermined temperature, wherein the delivery of each substance, over different temperature ranges encompassing the release temperatures of the plurality of devices, collectively produces a combined effect.