# US 11,998,108 B2 · Systems for determining brushing parameters in an electric toothbrush > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,998,108 B2 - Document ID: US11998108B2 - Status: Granted - Kind: B2 - Application number: 17/053,383 - Filed: 2019-05-10 - Published: 2021-07-29 - Granted: 2024-06-04 - Earliest claimed: 2018-05-10 - Assignees: Koninklijke Philips N.V. - Applicants: Koninklijke Philips N.V. - Inventors: Taylor Bevis - Web page: https://patentgrep.com/patent/US11998108B2 ## CPC - A46B 15/0006: {with a controlling brush technique device, e.g. stroke movement measuring device} - A46B 5/0037: {Flexible resilience by plastic deformation of the material} - A46B 9/04: {Arranged like in or} for toothbrushes - A46B 13/00: Brushes with driven brush bodies {or carriers}(power-driven toothbrushes A61C17/16) - A46B 13/02: power-driven {carriers} - A46B 15/0012: {with a pressure controlling device} - A61C 17/221: {Control arrangements therefor} - A46B 2200/1066: Toothbrush for cleaning the teeth or dentures (A61C17/16 takes precedence; bristles arrangements for toothbrushes A46B9/04) - A46B: BRUSHES (handles not integral with brushware B25G) - A61C: DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE (non-driven toothbrushes A46B; {tongue scrapers A61B17/24;} preparations for dentistry A61K6/00; preparations for cleaning the teeth or mouth A61K8/00, A61Q11/00) ## Abstract A brush head (12), an electric toothbrush (10), and a method of operating an electric toothbrush. The electric toothbrush (10) includes bristles extending from a base structure. A plurality of tufts (20) are formed as separate groups of the bristles (23) bundled together. A sensor assembly (28) is configured to generate, for each of the tufts, a signal representative of a force applied to each of the tufts. A controller (18) is configured to generate a tuft signature representing a distribution of the force applied to each of the tufts. This tuft signature may then be classified by appropriate algorithms to determine brushing parameters, such as applied pressure, angle, and the location in the user's mouth. ## Claims ### Claim 1 A brush head for an electric toothbrush, comprising: bristles extending from a base structure; and an array of tufts, each tuft formed as a separate group of the bristles bundled together; a sensor assembly configured to generate, for each of the tufts, a signal representative of a force applied to each of the tufts; and a controller configured to generate a tuft signature representing a distribution of the force applied across the array of tufts, wherein the controller is further configured to receive positional data from a position sensor and to fuse the positional data with the tuft signature to recalibrate or verify a determined position of the brush head in a user's mouth. ### Claim 2 (depends on 1) The brush head of claim 1, wherein each of the tufts is movable with respect to the base structure in response to the force, and the sensor assembly is configured to selectively form an electrical connection to generate the signal when the force exceeds a threshold. ### Claim 3 (depends on 2) The brush head of claim 2, wherein the base structure includes a rigid platen to which a conductive element is mounted and a flexible layer in which the tufts are embedded, and wherein resiliency of the flexible layer enables the tufts to move relative to the base structure. ### Claim 4 (depends on 3) The brush head of claim 3, wherein each of the tufts is provided with a conductive surface that is moved into contact the conductive element when the force exceeds the threshold. ### Claim 5 (depends on 3) The brush head of claim 3, further comprising a conductive layer for one or more of the tufts that is pushed by a corresponding one of the tufts into contact with the conductive element when the force exceeds the threshold. ### Claim 6 (depends on 3) The brush head of claim 3, wherein the conductive element is a discontinuous element and the electrical connection electrically connects the discontinuous element. ### Claim 7 (depends on 6) The brush head of claim 6, wherein the discontinuous element includes two planar halves or two raised pads. ### Claim 8 (depends on 1) The electric toothbrush of claim 1 wherein the controller is configured to classify an angle of the brush head relative to a user's teeth depending on the tuft signature. ### Claim 9 (depends on 1) The electrical toothbrush of claim 1, wherein the controller is configured to classify a pressure exerted by the brush head onto a user's teeth depending on the tuft signature. ### Claim 10 A brush head for an electric toothbrush, comprising: bristles extending from a base structure; and an array of tufts, each tuft formed as a separate group of the bristles bundled together; a sensor assembly configured to generate, for each of the tufts, a signal representative of a force applied to each of the tufts; and a controller configured to generate a tuft signature representing a distribution of the force applied across the array of tufts, wherein the tuft signature includes a plurality of training tuft signatures and a current tuft signature, wherein the controller is configured to create, during a training process, a signature map associating each of the training tuft signatures to particular locations in a user's mouth, and wherein the controller is configured to determine, during use, a location of the brush head in the user's mouth by comparing the current tuft signature to the signature map.