Electric ratchet for a powered screwdriver
AssigneeMedtronic Xomed, Inc.
InventorsChristopher L. Fair, Michael L. Koltz, Jr.
Life of this patent
Estimating the term…
Abstract
A powered screwdriver system includes an electric ratchet. In accordance with one aspect, the powered screwdriver system includes a driver housing and includes a motor disposed within the housing. A working end provides a rotational output and is mechanically coupled to the rotor. A power source provides power to the motor. A controller receives signals representative of a motor condition and, based on the received signals, controls the motor in a manner providing the electric ratchet.
Claims23
A powered screwdriver system comprising:
- a driver housing having a handle portion;
- a motor disposed within the housing, wherein the motor comprises a stator and a rotor, and wherein the rotor is disposed within the stator;
- a power source arranged to provide power to the motor;
- and
- a controller configured to control the motor to provide an electric ratchet capability including
- commutating the motor to maintain a rotational position of the rotor relative to the stator while loading is applied in a first direction on the motor, and
- permitting freewheel displacement of the rotor relative to the stator while loading is applied in a second direction on the motor, wherein the second direction is opposite the first direction.
A powered screwdriver system comprising:
- a handpiece driver comprising
- a housing having a handle portion configured for gripping by a user,
- a motor disposed within the housing, wherein the motor comprises a stator and a rotor, and wherein the rotor is rotationally disposed within the stator, and
- a working end providing a rotational output, wherein the working end is mechanically coupled to the rotor;
- and
- a control console separate from and in electrical communication with the handpiece driver,
- wherein
- the control console comprises a controller,
- the controller is configured to commutate the motor to maintain a desired relative position of the rotor within the stator when loading is applied in a first direction on the motor, and permit freewheel displacement of the rotor within the stator when loading is applied in a second direction on the motor,
- the handpiece driver is configured to emit signals representative of an actual rotor position relative to the stator,
- the control console is configured to establish a desired rotor position, receive the signals representative of the actual rotor position from the handpiece driver, and determine when the actual rotor position deviates from the desired rotor position, and
- the controller is configured to commutate the motor when the actual rotor position deviates from the desired rotor position over a preset threshold amount.
A method of operating a surgical screwdriver system comprising:
- estimating a starting rotor position of a motor relative to a stator;
- setting a first desired rotor position relative to the stator that is substantially equivalent to the starting rotor position;
- commutating the motor to substantially maintain the first desired rotor position relative to the stator and offset loading on the rotor applied in a first direction;
- permitting displacement of an actual rotor position within the stator in response to loading applied on the rotor in a second direction;
- and
- setting a second desired rotor position relative to the stator that is substantially equivalent to the displaced rotor position.
Dependencies are inferred from the claim text.