Self-adjusting preload for memory alloy wire

• US 10,029,829 B2
• Filed: 03/05/2015
• Issued: 07/24/2018
• Est. Priority Date: 01/24/2011
• Status: Active Grant

• Current Assignee: Carefusion 303 Incorporated (Becton, Dickinson & Co)
• Original Assignee: Carefusion 303 Incorporated (Becton, Dickinson & Co)
• Inventors: Weber, Frank Dean, Potakowskyj, Christoph, Bayer, Ernst
• Primary Examiner(s): Williams, Mark A
• Application Number:
  US14/639,965
• Publication Number:
  US 20150175321A1
• Time in Patent Office: 1,237 Days
• Field of Search: 292220
• CPC Class Codes: B65D 2251/10 Details of hinged closures
• CPC Class Codes: B65D 2251/1066 Actuating means
• CPC Class Codes: B65D 2543/00194 square or rectangular
• CPC Class Codes: B65D 43/164 and connected by interfitting hinge elements integrally with the container and the lid formed respectively
• CPC Class Codes: B65D 43/26 Mechanisms for opening or closing, e.g. pedal-operated for refuse receptacles B65F1/1623
• CPC Class Codes: E05B 47/0009 with thermo-electric actuators, e.g. heated bimetals
• CPC Class Codes: E05B 65/006 for covers or panels for manholes E02D29/1427; for holes enabling access to installations in buildings E04F19/08; for pressure vessels F16J13/00
• CPC Class Codes: E05C 3/30 in the form of a hook hook-like fastenings E05C19/10; locks for sliding wings with pivoting bolts E05B65/0811, E05B65/0835
• CPC Class Codes: F03G 7/0614 using shape memory elements
• CPC Class Codes: F03G 7/065 using a shape memory element
• CPC Class Codes: Y10T 292/1047 Closure
• CPC Class Codes: Y10T 292/1052 Operating means
• CPC Class Codes: Y10T 292/68 Keepers

Abstract

A preload mechanism for a memory alloy wire actuator is disclosed that includes a rotating element configured to rotate about a pivot. The rotating element has a first contact point that is configured to couple to the memory alloy wire actuator such that contraction of the memory alloy wire actuator displaces the first contact point such that the rotating element rotates from a first position to a second position. The preload mechanism also includes a bias element with a first end that is coupled to a second contact point of the rotating element and a second end configured to be pinned relative to the pivot. The bias element has a line of action extending from the second end through the first end. The line of action has an offset distance that is the minimum distance between the line of action and the pivot. The offset distance has a first value when the rotating element is in the first position and a second value when the rotating element is the second position, the second value being smaller than the first value.

Claims

1. A preload mechanism for a memory alloy wire actuator, the preload mechanism comprising:

a rotating element configured to rotate about a pivot, the rotating element coupled with the memory alloy wire actuator at a first contact point that is displaced upon contraction of the memory alloy wire actuator such that the rotating element rotates from a first position to a second position; and

a bias element having first and second ends, the first end coupled with the rotating element at a second contact point and the second end configured to be fixed relative to the pivot, wherein;

the bias element has a line of action extending from the second end through the first end,

the preload mechanism comprises an offset distance that is a minimum distance measured orthogonally from the pivot to the line of action, the offset distance having a first value when the rotating element is in the first position and a second value when the rotating element is the second position, and

the first contact point is a knife edge coupling the rotating element to the memory alloy wire actuator, the memory alloy wire actuator comprising a memory alloy wire wrapped around a capstan forming the knife edge, to receive an arm of the rotating element.

2. The preload mechanism of claim 1, wherein the bias element comprises a spring element having a spring constant.

3. The preload mechanism of claim 2, wherein the bias element is selected from the group consisting of a torsion spring, a linear coil compression spring, a diaphragm spring, an elastic tension element, a gas spring, and a constant force mechanism.

4. The preload mechanism of claim 1, wherein the rotating element is configured such that a translational acceleration of the preload mechanism does not generate a torsional moment on the rotating element about the pivot.

5. The preload mechanism of claim 1, further comprising a mass fixedly coupled to a side of the rotating element about the pivot and configured to place a center of gravity of the rotating element at the pivot.

6. The preload mechanism of claim 1, wherein the first value of the offset distance is greater than the second value of the offset distance.

7. The preload mechanism of claim 1, wherein a torque applied to the rotating element by the bias element in the first position is lower than an opposite torque applied to the rotating element by the bias element in the second position.

8. The preload mechanism of claim 1, wherein the capstan is coupled to a latch release mechanism configured to open a lidded container.

9. The preload mechanism of claim 8, wherein the lidded container is configured to receive an electronic signal to actuate the memory alloy wire actuator.

10. The preload mechanism of claim 9, wherein the lidded container is one of a plurality of lidded containers in an automated dispensing machine, the automated dispensing machine comprising a cabinet to store the plurality of lidded containers, an electronic circuitry to provide the electronic signal to at least one of the lidded containers, and a controller to provide commands to the electronic circuitry and determine which lidded container receives the electronic signal.

11. The preload mechanism of claim 10, wherein at least one of the plurality of lidded containers is integrally formed into a structure of the cabinet.

12. The preload mechanism of claim 10, wherein at least one of the plurality of lidded containers is detachable from a structure of the cabinet.

13. The preload mechanism of claim 1, wherein the pivot and the second end of the bias element are pinned to a body of a lidded container.

14. The preload mechanism of claim 1, wherein the rotating element is coupled to the memory alloy wire actuator such that a displacement of the first contact point is substantially parallel to a contraction of two parallel portions of the memory alloy wire.