Ambulatory infusion device
AssigneeRoche Diabetes Care, Inc.
InventorHans List
Life of this patent
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Abstract
An ambulatory infusion device including a pump drive unit, a valve drive unit and a control unit. The pump drive unit includes a pump actuator and a pump driver coupled to a piston of a metering pump unit. The valve drive unit includes a valve actuator and a valve driver coupled to a valve unit for transmitting a valve switching force or torque. The control unit controls a repeated execution of: (a) placing the valve unit in a filling state; (b) displacing the piston in a retraction direction; (c) displacing the piston in an advancing direction by a backlash compensation distance; (d) switching the valve unit from the filling state into a draining state; and (e) further displacing the piston in the advancing direction in a number of incremental steps over an extended time period.
Claims13
Ambulatory infusion device for use with a valve unit and a metering pump unit having a piston, the ambulatory infusion device including:
- a pump drive unit including a pump actuator and a pump driver, the pump driver being coupled to the pump actuator and being coupleable to the piston of the metering pump unit to thereby transmit a pump driving force and/or pump driving torque from the pump actuator to the piston;
- a valve drive unit including a valve actuator and a valve driver, the valve driver being coupled to the valve actuator and being coupleable to the valve unit to thereby transmit a valve switching force and/or valve switching torque from the valve actuator to the valve unit;
- a control unit being configured to control a repeated execution of a sequence of steps including:
- (a) operating the valve actuator to switch the valve unit to a filling state;
- (b) operating the pump actuator to move the piston in a retraction direction;
- (c) operating the pump actuator to move the piston a backlash compensation distance in an advancing direction, the advancing direction being opposite to the retraction direction;
- (d) operating the valve actuator to switch the valve unit from the filling state to a draining state;
- (e) operating the pump actuator to further move the piston in the advancing direction in a plurality of incremental steps over an extended time period.
A method of compensating for backlash in a dosing unit for liquid drug infusion, the method including repeatedly executing a sequence of the following steps:
- (a) switching a valve unit into a filling state;
- (b) moving a piston in a retraction direction into a retracted piston position;
- (c) moving the piston by a backlash compensation distance in an advancing direction, the advancing direction being opposite to the retraction direction;
- (d) switching the valve unit from the filling state into a draining state;
- (e) further moving the piston in the advancing direction in a plurality of incremental steps over an extended time period to an advanced piston position.
Dependencies are inferred from the claim text.