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

Patent metadata

Field	Value
Publication number	US-12325097-B2
Application number	US-202318509714-A
Country	US
Kind code	B2
Filing date	Nov 15, 2023
Priority date	Jul 18, 2018
Publication date	Jun 10, 2025
Grant date	Jun 10, 2025

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. In one example, the cutting device includes a cutting wheel; an actuator to rotate the cutting wheel; a power source configured to provide power to the actuator for rotating the cutting wheel at an adjustable rotational velocity; and control circuitry configured to adjust the rotational velocity of the cutting wheel to maintain a substantially constant surface speed.

First claim

What is claimed is:

1. A cutting device, comprising:
an actuator configured to rotate a cutting wheel;
a power source configured to provide power to the actuator for rotating the cutting wheel at an adjustable rotational velocity; and
control circuitry configured to adjust the rotational velocity of the cutting wheel to maintain a substantially constant surface speed,
wherein the control circuitry is configured to provide a warning when a change rate for a diameter of the cutting wheel is greater than a first threshold, and to adjust the rotational velocity of the cutting wheel to zero when the change rate is greater than a second threshold that is greater than the first threshold.

2. The cutting device of claim 1 , wherein the constant surface speed is one of a plurality of constant surface speeds.

3. The cutting device of claim 1 , wherein the control circuitry is configured to determine a present diameter of the cutting wheel based on power drawn by the actuator to rotate the cutting wheel at a present rotational velocity.

4. The cutting device of claim 1 , wherein the control circuitry is configured to adjust the rotational velocity of the cutting wheel based on a present diameter to maintain a substantially constant surface speed of the cutting wheel.

5. The cutting device of claim 1 , further comprising a sensor configured to determine a distance from the sensor to at least one of a surface of an item being cut by the cutting wheel and a member supporting the item, wherein the distance is used to determine a present diameter of the cutting wheel.

6. The cutting device of claim 5 , further comprising a sensor configured to detect 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.

7. The cutting device of claim 1 , wherein the control circuitry is configured to determine a present diameter of the cutting wheel based on an amount of time the cutting device is in operation.

8. The cutting device of claim 1 , wherein the control circuitry is configured to determine a present diameter of the cutting wheel based on an amount of time the cutting wheel is in contact with an item being cut.

9. The cutting device of claim 1 , wherein the constant surface speed is correlated to a type of material being cut.

10. A cutting device, comprising:
an actuator configured to rotate a cutting wheel;
a power source configured to provide power to the actuator for rotating the cutting wheel at an adjustable rotational velocity; and
control circuitry configured to:
determine a present diameter of a cutting wheel of the cutting device;
adjust 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;
provide a warning when a change rate for a diameter of the cutting wheel is greater than a first threshold; and
adjust the rotational velocity of the cutting wheel to zero when the change rate is greater than a second threshold that is greater than the first threshold.

11. The cutting device of claim 10 , wherein the present diameter is determined upon demand by a user of the cutting device or periodically without user input.

12. The cutting device of claim 10 , wherein the constant surface speed is one of a plurality of constant surface speeds.

13. The cutting device of claim 10 , 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.

14. The cutting device of claim 10 , wherein determining the present diameter comprises determining an amount of power drawn by the actuator to rotate the cutting wheel at a present rotational velocity.

15. The cutting device of claim 10 , 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.

16. The cutting device of claim 10 , wherein the present diameter is determined 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.

17. A cutting device, comprising:
an actuator configured to rotate a cutting wheel;
a power source configured to provide power to the actuator for rotating the cutting wheel at an adjustable rotational velocity; and
control circuitry configured to:
determine a present diameter of a cutting wheel of the cutting device;
adjust 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;
compare the present diameter with a previous diameter;
determine a change rate of the present diameter;
when the change rate is greater than a first threshold, adjust the rotational velocity of the cutting wheel to zero; and
provide a warning when the change rate is less than or equal to the first threshold and greater than or equal to a second threshold.

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

• G05B19/416

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

• B23Q15/16

  Compensation for wear of the tool · CPC title

• G01B11/10

  of objects while moving · CPC title

• B26D2001/0046

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

• B26D1/0006

  Cutting members therefor · CPC title