Granted Patent B2

US 12,749,748 · App. 18/774,376 · Granted Sep 29, 2026

Inventors: Timothy R. Obermann (Waukesha, WI); David W. Siegler (New Berlin, WI); Alexander Huber (Menomonee Falls, WI); William F. Chapman, III (Delevan, WI); Patrick D. Gallagher (New Berlin, WI); Timothy J. Bartlett (Waukesha, WI)

Assignee: MILWAUKEE ELECTRIC TOOL CORPORATION

H01M50/20H02P6/06

Abstract

Claims (56)

1 . A gas engine replacement device, comprising:

a housing;

a vibration sensor;

a battery receptacle coupled to the housing and configured to removably receive a battery pack;

a motor located within the housing;

a power take-off shaft receiving torque from the motor and protruding from a side of the housing;

a power switching network configured to selectively provide power from the battery pack to the motor; and

an electronic processor coupled to the power switching network and configured to control the power switching network to rotate the motor, the electronic processor configured to:

receive a command speed for the motor,

determine an output speed for the motor different than the command speed based on an output of the vibration sensor, and

control the power switching network to rotate the motor in accordance with the determined output speed;

wherein the electronic processor is configured to determine the output speed for the motor by:

identifying a resonant frequency of a mechanical system coupled to the motor based on the output of the vibration sensor,

generating an exclusion zone based on the identified resonant frequency, and

setting the output speed for the motor based on whether the command speed is in or outside of the exclusion zone.

2 . The gas engine replacement device of claim 1 , wherein the electronic processor is configured to determine the output speed for the motor by:

determining an exclusion zone based on the output of the vibration sensor;

setting the output speed for the motor at the command speed responsive to the command speed being outside the exclusion zone, and

setting the output speed to a speed outside the exclusion zone responsive to the command speed being in the exclusion zone.

3 . The gas engine replacement device of claim 2 , wherein the electronic processor is further configured to set the output speed to a speed outside a second exclusion zone responsive to the command speed being in the second exclusion zone.

4 . The gas engine replacement device of claim 2 , wherein the electronic processor is further configured to set the output speed to a limit of the exclusion zone responsive to the command speed being in the exclusion zone and a previous output speed of the motor being outside the exclusion zone.

5 . The gas engine replacement device of claim 2 , wherein the electronic processor is configured to determine the exclusion zone based on the output of the vibration sensor by dynamically setting one or more limits of the exclusion zone based on the output of the vibration sensor.

6 . The gas engine replacement device of claim 5 , wherein the output of the vibration sensor is a first output and wherein the electronic processor is configured to dynamically set the one or more limits of the exclusion zone by:

setting a first limit of the exclusion zone responsive to the first output of the vibration sensor exceeding a first threshold; and

after setting the first limit and responsive to a change in the command speed of the motor:

setting the output speed of the motor to a provisional command speed;

receiving a second output of the vibration sensor with the output speed set to the provisional command speed; and

setting a second limit of the exclusion zone responsive to the second output of the vibration sensor being below the first threshold.

7 . The gas engine replacement device of claim 6 , wherein the provisional command speed is set at predetermined increments of the change of the command speed.

8 . The gas engine replacement device of claim 1 , wherein the output of the vibration sensor is a first output and wherein the electronic processor is configured to determine the output speed for the motor by:

limiting the output speed to a first value responsive to the first output of the vibration sensor exceeding a first threshold,

setting the output speed to a provisional command speed, and

responsive to a second output of the vibration sensor exceeding the first threshold at the provisional command speed, returning the output speed to the first value.

9 . The gas engine replacement device of claim 8 , wherein the electronic processor is further configured to, responsive to the second output of the vibration sensor being below the first threshold, continue operation of the motor at the provisional command speed.

10 . The gas engine replacement device of claim 8 , wherein the provisional command speed is set at predetermined increments of a change of the command speed.

11 . The gas engine replacement device of claim 1 , wherein the exclusion zone defines a hysteresis around the resonant frequency.

12 . A method for operating a gas engine replacement device, comprising:

receiving, with an electronic processor of the gas engine replacement device, a command speed for a motor included in the gas engine replacement device;

determining, with the electronic processor, an output speed for the motor different than the command speed based on an output of a vibration sensor included in the gas engine replacement device, and

controlling, with the electronic processor, a power switching network included in the gas engine replacement device to rotate the motor in accordance with the determined output speed;

wherein determining the output speed for the motor includes:

identifying a resonant frequency of a mechanical system coupled to the motor based on the output of the vibration sensor,

generating an exclusion zone based on the identified resonant frequency, and

setting the output speed for the motor based on whether the command speed is in or outside of the exclusion zone.

13 . The method of claim 12 , wherein determining the output speed for the motor includes:

determining an exclusion zone based on the output of the vibration sensor;

setting the output speed for the motor at the command speed responsive to the command speed being outside the exclusion zone, and

setting the output speed to a speed outside the exclusion zone responsive to the command speed being in the exclusion zone.

14 . The method of claim 13 , further comprising setting, with the electronic processor, the output speed to a speed outside of a second exclusion zone responsive to the command speed being in the second exclusion zone.

15 . The method of claim 13 , further comprising setting, with the electronic processor, the output speed to a limit of the exclusion zone responsive to the command speed being in the exclusion zone and a previous output speed of the motor being outside the exclusion zone.

16 . The method of claim 12 , wherein the output of the vibration sensor is a first output and wherein determining the output speed for the motor includes:

limiting the output speed to a first value responsive to the first output of the vibration sensor exceeding a first threshold,

setting the output speed to a provisional command speed, and

responsive to a second output of the vibration sensor exceeding the first threshold at the provisional command speed, returning the output speed to the first value.

17 . The method of claim 16 , further comprising, responsive to the second output of the vibration sensor being below the first threshold, continuing operation of the motor at the provisional command speed.

18 . The method of claim 16 , wherein the provisional command speed is set at predetermined increments of a change of the command speed.

Assignments (1)

Continuity (4)

References Cited (63)