Controlled delivery drive mechanisms for drug delivery pumps

1. A controlled delivery drive mechanism for a drug delivery pump, comprising:

a drive housing;

a piston having an interface surface;

at least one biasing member initially retained in an energized state and configured to bear upon the interface surface of the piston;

a tether connected at one end to the piston and at another end to a winch drum, the tether configured to restrain expansion of the at least one biasing member; and

an escapement regulating mechanism configured to meter release of the tether by the winch drum, wherein release of the at least one biasing member from the initial energized state applies tension to the tether, the tension to the tether imparting a drive torque to the escapement regulating mechanism and initiating an impulse action of the escapement regulating mechanism to initiate the metered release of the tether, the metered release of the tether providing for controlled expansion of the at least one biasing member.

2. The controlled delivery drive mechanism of claim 1 , further comprising:

a drug container having a plunger seal located within a barrel, wherein the piston is configured to axially translate the plunger seal within the barrel.

3. The controlled delivery drive mechanism of claim 2 , wherein the drug container contains a drug fluid within a drug chamber of the barrel.

4. The controlled delivery drive mechanism of claim 1 , wherein the metering of the tether by the escapement regulating mechanism controls a rate or profile of drug delivery to a user.

5. The controlled delivery drive mechanism of claim 1 , wherein the escapement regulating mechanism comprises a gear train having one or more gears, wherein rotation of at least one gear of the gear train is coupled to rotation of the winch drum.

6. The controlled delivery drive mechanism of claim 5 , wherein the escapement regulating mechanism further comprises a lever and an escape wheel configured to engage with the gear train and meter rotational movement of the gear train.

7. The controlled delivery drive mechanism of claim 6 , wherein the escape wheel is a compound gear including at least two escape gears of different diameter, one of the at least two escape gears comprising escape teeth and another of the at least two escape gears configured to engage with the gear train.

8. The controlled delivery drive mechanism of claim 6 , wherein the lever includes pins and a prong, the prong configured to moveably engage a post and an impulse pin of a balance wheel, the balance wheel configured to oscillate about the post in combination with a hair spring.

9. The controlled delivery drive mechanism of claim 8 further comprising an actuator that at least partially controls oscillation of the balance wheel.

10. The controlled delivery drive mechanism of claim 9 , wherein the actuator is a mechanical actuator, an electrical actuator, or an electromechanical actuator.

11. The controlled delivery drive mechanism of claim 6 , wherein the gear train comprises a winch gear rotationally coupled to the winch drum and configured to engage at least one compound gear, the at least one compound gear configured to engage directly or indirectly with the escape wheel, the at least one compound gear thereby coupling rotation of the escape wheel to rotation of the winch drum.

12. The controlled delivery drive mechanism of claim 1 , further comprising a status reader configured to recognize one or more status triggers incrementally spaced on the tether.

13. The controlled delivery drive mechanism of claim 12 , wherein the status reader is an optical status reader and the one or more status triggers are optical status triggers.

14. The controlled delivery drive mechanism of claim 12 , wherein the status reader is an electromechanical status reader and the one or more status triggers are electromechanical status triggers.

15. The controlled delivery drive mechanism of claim 1 , wherein the escapement regulating mechanism is configured to transition between the impulse action and a locking action based on oscillating movement of a balance wheel.

16. The controlled delivery drive mechanism of claim 15 , wherein a rate of oscillation of the balance wheel provides for a rate of metered release of the tether.

17. A drug delivery pump comprising:

a housing;

an insertion mechanism;

a fluid pathway connection;

a power and control system; and

a controlled delivery drive mechanism comprising:

a drive housing;

a piston having an interface surface;

at least one biasing member initially retained in an energized state and configured to bear upon the interface surface of piston;

a tether connected at one end to the piston and at another end to a winch drum, the tether configured to restrain expansion of the at least one biasing member; and

an escapement regulating mechanism configured to meter release of the tether by the winch drum, wherein release of the at least one biasing member from the initial energized state applies tension to the tether, the tension to the tether imparting a drive torque to the escapement regulating mechanism and initiating an impulse action of the escapement regulating mechanism to initiate the metered release of the tether, the metered release of the tether providing for controlled expansion of the at least one biasing member;

wherein the power and control system is configured to receive one or more inputs to meter the release of tether by the winch drum and permit axial translation of the piston by the biasing member.

18. The drug delivery pump of claim 17 , wherein the one or more inputs are received from an activation mechanism configured to be acted upon by a user.

19. The drug delivery pump of claim 17 , wherein the power and control system is configured to adjust an amount of restraint provided by the tether and winch drum on the axial translation of the piston to start, stop, or pause operation of the drive mechanism based on the one or more inputs.

20. The drug delivery pump of claim 17 , wherein the power and control system is configured to adjust an amount of restraint provided by the tether and winch drum on the axial translation of the piston to change a dose volume or a delivery rate for delivery to a user based on the one or more inputs.