Power tool hall effect mode selector switch

Patent metadata

Field	Value
Publication number	US-10414033-B2
Application number	US-201313815710-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Oct 4, 2012
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

A mode selector switch for a power tool that can have a source of a magnetic field and use a magnetoresistive component to produce an output signal that changes when the strength of the magnetic field changes. The power tool can have a microprocessor that changes an operational mode of the power tool based on a change of the output signal from the magnetoresistive component. The magnetoresistive component can be a Hall effect sensor and the power tool can be a nailer. The power tool can have a switching means which changes an operational mode based upon a change in the strength of the magnetic field upon a magnetoresistive component. A method of controlling a power tool, having a step of changing an operational mode of a power tool based upon identifying a change in output from a magnetoresistor.

First claim

We claim:

1. A power tool, comprising:
a mode selector switch having a knob that when moved from a first position to a second position affects an output signal of a linear Hall effect sensor to a microprocessor configured to change an operational mode of the power tool from a first operational mode to a second operational mode different from the first operational mode when the output signal changes;
the mode selector switch capable of causing a first magnet and a second magnet to move a distance of a throw;
the first magnet and the second magnet when moved the distance of the throw effect a change from the first operational mode to the second operational mode;
the first magnet having at least a first magnetic field providing a first magnetic source to the mode selector switch;
the second magnet having at least a second magnetic field providing a second magnetic source to the mode selector switch;
the linear Hall effect sensor affixed to a circuit board and configured to produce the output signal that changes when the strength of at least one of the first magnetic field and the second magnetic field experienced by the linear Hall effect sensor changes;
the linear Hall effect sensor having a facing surface and the magnet having a face, the facing surface configured at a sensing distance from the face of the first magnet.

2. The power tool according to claim 1 , wherein the power tool is a nailer.

3. The power tool according to claim 2 , wherein the operational mode is a sequential mode.

4. The power tool according to claim 2 , wherein the operational mode is a nonsequential mode.

5. The power tool according to claim 2 , wherein the operational mode is a bump mode.

6. The power tool according to claim 2 , wherein the operational mode is a bump mode when the output of the linear Hall effect sensor is in a range of from 5 mT at 1.7V to 55 mT at 2.8 V.

7. The power tool according to claim 2 , wherein the operational mode is a sequential mode when the output of the linear Hall effect sensor is in a range of negative 60 mT at 0.0 V to less than 5 mT at less than 1.7 V, and when the output of the linear Hall effect sensor is greater than 55 mT at greater than 2.7 V.

8. The power tool according to claim 1 , wherein the source of at least the first magnetic field is a magnet and a distance between a portion of the magnet and a portion of the linear Hall effect sensor is a value in a range of 0.1 mm to 6.00 mm.

9. The power tool according to claim 1 , wherein the operational mode is switched to sequential mode when a fault condition is detected regarding the output signal.

10. The power tool according to claim 1 , wherein the throw is equal to or greater than the sensing distance.

11. The power tool according to claim 1 , wherein the throw is equal to or less than the sensing distance.

12. The power tool according to claim 1 , wherein a zero flux density experienced by the linear Hall effect sensor causes an output of the linear Hall effect sensor resulting from the zero flux density to be sent to the microprocessor that changes the mode of operation of the power tool to a sequential mode of operation of the power tool in response to such output.

13. The power tool according to claim 1 , wherein the microprocessor is configured such that when the linear Hall effect sensor experiences a one or more magnetic fields not originating from a magnet of the mode selector switch the resulting output from the linear Hall effect sensor experiencing the one or more magnetic fields not originating from a magnet of the mode selector switch does not cause a change in operational mode of the tool.

14. The power tool according to claim 1 , wherein the microprocessor is configured such that a bump mode occurs only when the linear Hall effect sensor transmits an output in a sensor range indicating the linear Hall effect sensor is experiencing a flux having a value that is at least 10% of the sensor range from a high sensor saturation point and at least 10% of the sensor range from a low sensor saturation point and at least 10% of the sensor range from a flux value of zero.

15. A power tool, comprising:
a switching means for switching the power tool from a first operational mode to a second operational mode different from the first operational mode;
the switching means having a first source of at least a first magnetic field;
the switching means having a second source of at least a second magnetic field;
the switching means adapted to move at least the first source from a first position to a second position;
a linear Hall effect sensor sensing the strength of at least one of the first magnetic field and the second magnetic field;
the linear Hall effect sensor having a fixed position in relation to a circuit board;
the linear Hall effect sensor having a sensing distance of 3 mm or greater between the linear Hall effect sensor and the first source;
the linear Hall effect sensor adapted to produce an output signal which is an analog output signal and which changes when the strength of at least one of the first magnetic field and the second magnetic field changes; and
a data processing means that processes the output signal and changes the first operational mode to the second operational mode when the output signal changes.

16. The power tool according to claim 15 , wherein the power tool is a nailer.

17. The power tool according to claim 15 , wherein the switching means comprises a means for changing the relative distance between the source of at least a first magnetic field and the linear Hall effect sensor.

18. The power tool according to claim 15 , wherein the switching means comprises a means for changing the relative distance between the source of at least a first magnetic field and the linear Hall effect sensor which is a member that can be moved and that has a magnet.

19. The power tool according to claim 15 , wherein the linear Hall effect sensor is a magnetoresistor.

20. The power tool according to claim 15 , wherein the data processing means is a microprocessor.

21. A method of controlling a power tool, comprising the steps of:
providing a switch adapted to change an operational mode of the power tool when a magnetic member is moved from a first position to a second position;
providing the magnetic member which has at least a first magnetic field; the magnetic member having a face;
providing a means to move the magnetic member from the first position to the second position;
providing a linear Hall effect sensor which has a magnetoresistor at a fixed location in the power tool detecting the first magnetic field and producing a first output of the magnetoresistor to a microprocessor; the linear Hall effect sensor having a facing surface;
the facing surface configured at a sensing distance which is 3 mm or greater from the face of the magnetic member;
exposing the magnetoresistor to a first magnetic flux of the first magnetic field;
moving the magnetic member a distance of a throw from the first position to the second position and exposing the magnetoresistor to a second magnetic flux different from the first magnetic flux; the exposing the magnetoresistor to a second magnetic flux producing a second output of the magnetoresistor to the microprocessor;
computationally identifying the change from the first output of the magnetoresistor to the second output of the magnetoresistor by the microprocessor; and
processing machine readable instructions by the microprocessor to change the operational mode of th

Assignees

• Black & Decker Inc

Inventors

• Ekstrom Erik
• Garber Stuart E
• Lim Jongsoo
• Smith David J
• Waikar Shailesh P

Classifications

• B25C1/06

  operated by electric power · CPC title

• G01D5/147

  influenced by the movement of a third element, the position of Hall device and the source of magnetic field being fixed in respect to each other · CPC title

• B25C1/00 Primary

  Hand-held nailing tools (hammers per se B25D; nailing machines B27F7/02); Nail feeding devices · CPC title

• B25F5/00

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title