Monitoring speed control and precision incrementing of motor for powered surgical instruments

Patent metadata

Field	Value
Publication number	US-2016256153-A1
Application number	US-201514640831-A
Country	US
Kind code	A1
Filing date	Mar 6, 2015
Priority date	Mar 6, 2015
Publication date	Sep 8, 2016
Grant date	—

Abstract

Motor speed control systems are disclosed that include a motor having an output shaft, a motor speed control system, a sensor to detect the speed of the motor, and a controller to receive a signal from the sensor and to control the speed of the output shaft. A gear reduction assembly is operably coupled to the output shaft and a detectable element located in the gear reduction assembly. The sensor senses the detectable element. The sensor is placed in the radial path of the detectable element. Another system includes a brushless motor having a housing and an output shaft, the brushless motor comprising electromagnetic field coils arrayed radially around a central magnetic shaft, a gear reduction assembly operably coupled to the output shaft, and a sensor placed in proximity to the brushless motor. The sensor communicates with a controller to control the speed of the output shaft.

First claim

What is claimed is:

1 . A motor speed control system comprising:
a motor having an output shaft; a gear reduction assembly operably coupled to the output shaft; a detectable element located in the gear reduction assembly; and at least one sensor to sense the detectable element, the at least one sensor placed in the radial path of the detectable element, the at least one sensor in data communication with a controller configured to receive a signal from the at least one sensor and to control the speed of the output shaft.

2 . The motor speed control system of claim 1 , wherein the gear reduction assembly comprises a planetary gear train.

3 . The motor speed control system of claim 2 , wherein the planetary gear train comprises a first stage, wherein the planetary gear train is driven by a sun gear attached directly or indirectly to the motor output shaft, and wherein the sun gear drives one or more first stage planet gears, which in turn engage a first stage annular gear.

4 . The motor speed control system of claim 3 , comprising a first stage carrier in communication with the first stage planet gears, the first stage carrier includes or connects to a second stage sun gear that drives the second stage.

5 . The motor speed control system of claim 2 , wherein the planetary gear train comprises at least one stage connected to a drive gear, which is configured as a final effector in the gear reduction assembly.

6 . The motor speed control system of claim 5 , wherein a single detectable element is placed on the drive gear.

7 . The motor speed control system of claim 1 , wherein the detectable element can be affixed or integral with any rotating part or particular stage of the gear reduction assembly to measure the number of times that the rotating part or stage rotates.

8 . The motor speed control system of claim 1 , wherein the at least one sensor is an inductance sensor and the detectable element is a metallic element.

9 . The motor speed control system of claim 8 , wherein the inductance sensor is configured to detect a change in inductance caused by the metallic element passing adjacent the inductive sensor.

10 . The motor control system of claim 1 , wherein the sensor is a magnetic field sensor and the detectable element is a magnetic element.

11 . A motor speed control system comprising:
a brushless motor having a housing and an output shaft, the brushless motor comprising electromagnetic field coils arrayed radially around a central magnetic shaft; a gear reduction assembly operably coupled to the output shaft; and at least one sensor placed in proximity to the brushless motor, the at least one sensor in data communication with a controller configured to receive a signal from the at least one sensor and to control the speed of the output shaft.

12 . The motor speed control system of claim 11 , comprising negative and positive electromagnetic field coils alternately arranged around the central magnetic shaft, wherein the coils are sequentially activated and deactivated to drive the central magnetic shaft.

13 . The motor speed control system of claim 12 , wherein the at least one sensor is placed adjacent to the negative and positive electromagnetic field coils outside the housing of the brushless motor to monitor motor speed.

14 . A powered surgical instrument comprising:
a motor having an output shaft; a motor speed control system in communication with the motor; at least one sensor to detect the speed of the motor; and a controller configured to receive a signal from the at least one sensor and configured to control the speed of the output shaft.

15 . The powered surgical instrument of claim 14 , wherein the motor speed control system comprises:
a gear reduction assembly operably coupled to the output shaft; and a detectable element located in the gear reduction assembly; wherein the at least one sensor is configured to sense the detectable element, the at least one sensor placed in the radial path of the detectable element.

16 . The powered surgical instrument of claim 15 , wherein the gear reduction assembly comprises a planetary gear train.

17 . The powered surgical instrument of claim 16 , wherein the planetary gear train comprises a first stage, wherein the planetary gear train is driven by a sun gear attached directly or indirectly to the motor output shaft, and wherein the sun gear drives one or more first stage planet gears, which in turn engage a first stage annular gear.

18 . The powered surgical instrument of claim 14 , wherein the motor speed control system comprises:
a brushless motor having a housing and an output shaft, the brushless motor comprising electromagnetic field coils arrayed radially around a central magnetic shaft; a gear reduction assembly operably coupled to the output shaft; and at least one sensor placed in proximity to the brushless motor, the at least one sensor in data communication with a controller configured to receive a signal from the sensor and to control the speed of the output shaft.

19 . The powered surgical instrument of claim 18 , comprising negative and positive electromagnetic field coils alternately arranged around the central magnetic shaft, wherein the coils are sequentially activated and deactivated to drive the central magnetic shaft.

20 . The powered surgical instrument of claim 19 , wherein the at least one sensor is placed adjacent to the negative and positive electromagnetic field coils outside the housing of the brushless motor to monitor motor speed.

Assignees

• Ethicon Endo Surgery Llc

Inventors

• Shelton Iv Frederick E
• Morgan Jerome R
• Harris Jason L

Classifications

• A61B2017/0003

  of parts of the instruments · CPC title

• H02P23/28

  Controlling the motor by varying the switching frequency of switches connected to a DC supply and the motor phases · CPC title

• B25F3/00

  Associations of tools for different working operations with one portable power-drive means; Adapters therefor · CPC title

• H02K7/145

  Hand-held machine tool · CPC title

• H02K11/21

  Devices for sensing speed or position, or actuated thereby (specially adapted for machines having non-mechanical commutating devices H02K29/06, H02K29/14) · CPC title