Air spring counterbalance

1. A method of operating a fluid-based spring counterbalance mechanism comprising a flexible-walled fluid-based spring, the method comprising:

operatively coupling a rotatable input shaft of the fluid-based spring counterbalance mechanism to a jackshaft configured to be operatively coupled to a movable barrier such that rotation of the jackshaft raises or lowers the movable barrier;

applying a first force by a movable barrier operator to change the position of the movable barrier, wherein the flexible-walled fluid-based spring exerts a second force that supports a portion of the weight of the movable barrier in addition to the first force.

2. The method of operating a fluid-based spring counterbalance of claim 1 , wherein the second force supports substantially an entire weight of the movable barrier.

3. The method of operating a fluid-based spring counterbalance of claim 1 , further comprising:

identifying by a controller an entire weight of the movable barrier by observing a change in position of the movable barrier in response to adding fluid to the flexible-walled fluid-based spring.

4. The method of operating a fluid-based spring counterbalance of claim 3 , further comprising varying by the controller a quantity of fluid in the flexible-walled fluid-based spring in response to identifying the entire weight of the movable barrier.

5. The method of operating a fluid-based spring counterbalance of claim 4 , further comprising maintaining the second force by varying a quantity of fluid in the flexible-walled fluid-based spring.

6. The method of operating a fluid-based spring counterbalance of claim 5 , wherein the varying the quantity of fluid is effected by connecting the flexible-walled fluid-based spring to a source of fluid.

7. The method of operating a fluid-based spring counterbalance of claim 1 , further comprising:

measuring by a controller a temperature;

varying a quantity of fluid by the controller in response to a change in the temperature.

8. The method of operating a fluid-based spring counterbalance of claim 1 , further comprising:

measuring by a controller a pressure of fluid contained within the flexible-walled fluid-based spring;

varying a quantity of fluid by the controller in response to a change in the pressure.

9. The method of operating a fluid-based spring counterbalance of claim 1 , further comprising:

measuring by a controller a position of the movable barrier;

varying a quantity of fluid by the controller in response to a change in the position.

10. The method of operating a fluid-based spring counterbalance of claim 1 , further comprising periodically varying a quantity of fluid within the flexible-walled fluid-based spring, by a controller.

11. The method of installing a fluid-based spring counterbalance of claim 1 , wherein the portion of the weight of the movable barrier is transmitted to the flexible-walled fluid-based spring by:

a reduction shaft operably coupled to the rotatable input shaft, and

a translational mechanism coupled to the reduction shaft, the translational mechanism configured to compress the flexible-walled fluid-based spring between two surfaces in response to rotation of the reduction shaft.

12. A method of counterbalancing a movable barrier by a flexible-walled fluid-based spring, the method comprising:

operatively coupling a flexible-walled fluid-based spring to a movable barrier such that a force exerted by the flexible-walled fluid-based spring supports at least a portion of a weight of a movable barrier;

securing a quantity of fluid within the flexible-walled fluid-based spring such that the flexible-walled fluid-based spring exerts a desired force when the movable barrier is at a particular position;

adjusting the quantity of fluid in the flexible-walled fluid-based spring such that the desired force remains substantially constant.

13. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 12 wherein the portion of the weight supported by the flexible-walled fluid-based spring varies with a position of the movable barrier.

14. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 12 wherein the force exerted by the flexible-walled fluid-based spring varies according to a position of the movable barrier.

15. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 12 , wherein the adjusting further comprises adding a fixed quantity of fluid by a controller after a particular period of time.

16. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 15 , wherein the adjusting further comprises:

detecting by a controller at least one input;

effecting by the controller the adjusting the quantity of fluid in response to the at least one input.

17. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 16 , wherein the detecting the at least one input comprises detecting one or more of a temperature, a pressure, or a position of the movable barrier.

18. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 17 , wherein the detecting one or more of the temperature or the pressure occurs in response to receiving an input indicating the movable barrier is in a predetermined position.

19. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 17 , further comprising executing the detecting one or more of the temperature or the pressure at particular intervals of time.

20. The method of counterbalancing a movable barrier by a flexible-walled fluid-based spring of claim 16 wherein the effecting by the controller opens a valve to release fluid from the flexible-walled fluid-based spring or connects the flexible-walled fluid-based spring to a source of fluid.