# US 11,207,756 B2 · Power tool blade type detection and automatic speed adjustment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,207,756 B2 - Document ID: US11207756B2 - Status: Granted - Kind: B2 - Application number: 16/382,636 - Filed: 2019-04-12 - Published: 2019-10-17 - Granted: 2021-12-28 - Earliest claimed: 2018-04-12 - Assignees: Milwaukee Electric Tool Corporation - Applicants: Milwaukee Electric Tool Corporation - Inventors: John S. Dey, IV; Corey J. Dickert - Web page: https://patentgrep.com/patent/US11207756B2 ## CPC - B23Q 15/12: Adaptive control, i.e. adjusting itself to have a performance which is optimum according to a preassigned criterion - B23D 45/044: {the saw blade being adjustable according to angle of cut (B23D45/025 takes precedence)} - B23D 59/001: {Measuring or control devices, e.g. for automatic control of work feed pressure on band saw blade (measuring in general G01; controlling in general G05)} - B23G 1/225: {automatically controlled} - B23D 45/042: {with the saw blade carried by a pivoted lever (B23D45/028, B23D45/065 take precedence)} - B23Q: DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING (tools of the kind used in lathes or boring machines B23B27/00); MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT - B23D: PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR (making toothed gears or the like B23F; cutting metal by applying heat locally B23K; arrangements for copying or controlling B23Q) - B23G: THREAD CUTTING; WORKING OF SCREWS, BOLT HEADS, OR NUTS, IN CONJUNCTION THEREWITH (making helical grooves by turning B23B5/48, by milling B23C3/32, by forging, pressing, or hammering B21K1/56, by grinding B24B19/02; arrangements for copying or controlling B23Q; thread-forming by corrugating tubes B21D15/04, by rolling B21H3/02) ## Abstract Systems and methods are provided for an electric tool (e.g., a power tool) that includes an output driver for receiving an accessory, and an accessory-type detector. A motor of the electric tool is coupled to the output driver for driving the accessory. The power tool also includes an operation trigger for activating the motor and a motor controller. The motor controller includes an electronic processor that is coupled to the accessory-type detector, the motor, the operation trigger, and a memory. The memory stores instructions that when executed by the electronic processor cause the motor controller to detect a characteristic of the accessory from output of the accessory-type detector. The motor controller determines an operational characteristic for the accessory based on the detected characteristic, and controls operation of the motor to drive the accessory according to the operational characteristic when the operation trigger is activated. ## Claims ### Claim 1 A power tool comprising: an output driver for receiving an accessory; an accessory-type detector; a motor coupled to the output driver for driving the accessory; an operation trigger for activating the motor; and a motor controller comprising an electronic processor coupled to the accessory-type detector, the motor, the operation trigger, and a memory, wherein the memory stores instructions that when executed by the electronic processor configure the motor controller to: detect, from output of the accessory-type detector, a characteristic of the accessory, determine an operational characteristic for the accessory based on the characteristic of the accessory detected by the motor controller, control operation of the motor to drive the accessory according to the operational characteristic when the operation trigger is activated, disable activation of the motor when the accessory-type detector detects that the accessory is not coupled to the output driver; and enable activation of the motor when the accessory-type detector detects that the accessory is coupled to the output driver; wherein the accessory-type detector includes a magnetic sensor, and wherein the accessory includes a magnet that impinges the magnetic sensor such that the magnetic sensor detects a magnetic field. ### Claim 2 (depends on 1) The power tool of claim 1, wherein the power tool is a saw and the accessory-type detector is mounted on a blade guard of the saw. ### Claim 3 (depends on 1) The power tool of claim 1, wherein the power tool is a saw and the accessory-type detector is mounted on a housing of the saw. ### Claim 4 (depends on 1) The power tool of claim 1, wherein the accessory is a saw blade and the accessory characteristic comprises a material of which the saw blade is made. ### Claim 5 (depends on 1) The power tool of claim 1, wherein the operational characteristic comprises a speed for rotating the motor that drives the output driver and the accessory. ### Claim 6 (depends on 1) The power tool of claim 1, wherein the characteristic of the accessory comprises a physical characteristic of the accessory or a modification made to the accessory. ### Claim 7 (depends on 1) The power tool of claim 1, further comprising: a material-type detector, wherein the accessory is a saw blade, wherein the memory stores further instructions that, when executed by the electronic processor configure the motor controller to detect, from output of the material-type detector, a characteristic of a workpiece for cutting by the saw blade, and wherein determining the operational characteristic for the accessory is further based on the detected characteristic of the workpiece. ### Claim 8 (depends on 1) The power tool of claim 1, wherein the magnetic sensor is a Hall effect sensor. ### Claim 9 (depends on 1) The power tool of claim 1, wherein the magnetic sensor outputs a voltage indicative of the sensed magnetic field. ### Claim 10 (depends on 9) The power tool of claim 9, wherein a first voltage is output when no magnetic field is sensed, a second voltage is output when a medium strength magnetic field is sensed, and a third voltage is output when a strong magnetic field is sensed.