Method and apparatus for maintaining a surface speed of a circular cutting device

Patent metadata

Field	Value
Publication number	US-11833632-B2
Application number	US-201916512655-A
Country	US
Kind code	B2
Filing date	Jul 16, 2019
Priority date	Jul 18, 2018
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

Provided is a disclosure for a cutting device configured to control a linear speed of a cutting wheel as the cutting wheel gets smaller with use.

First claim

What are claimed:

1. A method for controlling a rotational velocity of a cutting device, comprising:
determining a present diameter of a cutting wheel of the cutting device; and
adjusting a rotational velocity of the cutting wheel based on the present diameter to have a surface speed of the cutting wheel at substantially a pre-determined constant surface speed,
wherein determining the present diameter comprises determining an amount of power used to maintain a present rotational velocity, and
wherein the power is electric power and wherein the determining the present diameter comprises determining a distance from a sensor to at least one of a surface of an item being cut by the cutting wheel and a member supporting the item, and the distance is used to determine the present diameter of the cutting wheel.

2. The method of claim 1 , wherein the present diameter is determined upon demand by a user of the cutting device or periodically without user input.

3. The method of claim 1 , wherein determining the present diameter comprises detecting one or both of:
light or sound reflected from at least one reflector of the cutting wheel, and
light or sound reflected from the cutting wheel.

4. The method of claim 3 , comprising:
transmitting, by a source on a first side of the cutting wheel, light or sound toward the cutting wheel; and
receiving, by a sensor on a second side of the cutting wheel, the transmitted light or sound.

5. The method of claim 1 , wherein determining the present diameter is based on one or both of:
an amount of time the cutting device is in operation, or
an amount of time the cutting wheel is in contact with an item being cut.

6. The method of claim 5 , wherein:
when the amount of time the cutting device is in operation is used, an initial diameter of the cutting wheel when the cutting device starts the operation is used, and
when the amount of time the cutting wheel is in contact with an item being cut is used, an initial diameter of the cutting wheel prior to a first contact with the item being cut is used.

7. The method of claim 1 , wherein the constant surface speed is one of a plurality of constant surface speeds.

8. The method of claim 7 , wherein each of the plurality of constant surface speeds is correlated to a type of material being cut.

9. The method of claim 1 , comprising:
comparing the present diameter with a previous diameter;
determining a change rate of the present diameter; and
when the change rate is greater than a first threshold, adjusting the rotational velocity of the cutting wheel to zero.

10. The method of claim 9 , comprising providing a warning when the change rate is less than or equal to the first threshold and greater than or equal to a second threshold.

11. A method for controlling a rotational velocity of a cutting device, comprising:
determining a present diameter of a cutting wheel of the cutting device; and
adjusting a rotational velocity of the cutting wheel based on the present diameter to have a surface speed of the cutting wheel at substantially a pre-determined constant surface speed, wherein determining the present diameter is based on one or both of:
(i) an amount of time the cutting device is in operation and an initial diameter of the cutting wheel when the cutting device starts the operation, and
(ii) an amount of time the cutting wheel is in contact with an item being cut and an initial diameter of the cutting wheel prior to a first contact with the item being cut.

12. The method of claim 11 , wherein the present diameter is determined upon demand by a user of the cutting device or periodically without user input.

13. The method of claim 11 , wherein the constant surface speed is one of a plurality of constant surface speeds.

14. The method of claim 13 , wherein each of the plurality of constant surface speeds is correlated to a type of material being cut.

15. The method of claim 11 , wherein the present diameter is determined upon demand by a user of the cutting device or periodically without user input.

16. The method of claim 11 , wherein determining the present diameter comprises detecting one or both of:
light or sound reflected from at least one reflector of the cutting wheel, and
light or sound reflected from the cutting wheel.

17. The method of claim 11 , wherein determining the present diameter comprises determining an amount of power used to maintain a present rotational velocity.

18. The method of claim 11 , wherein the determining the present diameter comprises determining a distance from a sensor to at least one of a surface of an item being cut by the cutting wheel and a member supporting the item, and the distance is used to determine the present diameter of the cutting wheel.

19. A method for controlling a rotational velocity of a cutting device, comprising:
determining a present diameter of a cutting wheel of the cutting device;
adjusting a rotational velocity of the cutting wheel based on the present diameter to have a surface speed of the cutting wheel at substantially a pre-determined constant surface speed;
comparing the present diameter with a previous diameter;
determining a change rate of the present diameter;
when the change rate is greater than a first threshold, adjusting the rotational velocity of the cutting wheel to zero; and
providing a warning when the change rate is less than or equal to the first threshold and greater than or equal to a second threshold.

20. The method of claim 19 , wherein determining the present diameter comprises determining an amount of power used to maintain a present rotational velocity.

Assignees

• Illinois Tool Works

Inventors

• Beranek Sarah Marie
• Bussan John Edward
• Ceckowski Douglas A
• Chkaiban Christian
• Frid Chelsea B
• Joray Jeffrey E
• Keeble Michael E
• Kordus Bryan J
• Shtilman Michael

Classifications

• B26D2001/0046

  rotating continuously about an axis perpendicular to the edge · CPC title

• G05B2219/49074

  Control cutting speed · CPC title

• G05B19/416

  characterised by control of velocity, acceleration or deceleration (G05B19/19 takes precedence) · CPC title

• G05B19/4065

  Monitoring tool breakage, life or condition · CPC title

• G01B17/00

  Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations · CPC title