# US 10,477,848 B2 · Spool brake device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,477,848 B2 - Document ID: US10477848B2 - Status: Granted - Kind: B2 - Application number: 15/788,619 - Filed: 2017-10-19 - Published: 2018-07-19 - Granted: 2019-11-19 - Earliest claimed: 2017-10-19 - Assignees: Shimano Inc. - Applicants: Shimano Inc. - Inventors: Hiroki Ogose; Akira Niitsuma; Yuichiro Ishikawa - Web page: https://patentgrep.com/patent/US10477848B2 ## CPC - A01K 89/01555: {using magnets} - A01K: ANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS ## Abstract The spool brake device is equipped with a brake unit, a detector, and a controller. The controller controls the braking force by the brake unit based on the variation of the rotational speed of the spool detected by the detection unit. When the rotational speed is increasing, the controller controls the braking force by the brake unit in the regular braking mode. In the regular braking mode, the controller changes the braking force by the brake unit according to the rotational speed of the spool. In addition to it, when the rotational speed of the spool stops, the controller is to control the braking force by the brake unit in the first braking mode, during a period of predetermined time. In the first braking mode, the controller makes a braking force by the brake unit that is less than the braking force in the regular braking mode. In addition, after the predetermined time, the controller may make a braking force in a second braking mode by the braking unit that is less than the braking force in the first braking mode. ## Claims ### Claim 1 A spool brake device for braking a spool of a dual bearing reel, the spool brake device comprising: a brake unit configured to brake the spool; a detector configured to detect increase and decrease of a rotational speed of the spool; and a controller configured to control a braking force of the brake unit, wherein the braking force is controlled by the controller based on a detected increase or decrease of the rotational speed of the spool such that when the rotational speed of the spool is detected to be increasing, the controller sets the braking force according to a regular braking mode, and when the rotational speed of the spool is detected to stop increasing, the controller sets the braking force according to a first braking mode, wherein the braking force of the first braking mode is less than the braking force of the regular braking mode. ### Claim 2 (depends on 1) The spool brake device of claim 1 wherein the braking force of the regular breaking mode is about 8-10 millimeter Nm. ### Claim 3 (depends on 1) The spool brake device of claim 1 wherein the controller is configured to set the braking force to the first braking mode for a predetermined period of time. ### Claim 4 (depends on 3) The spool brake device of claim 3 wherein after the predetermine period of time has elapsed, the controller is configured to set the braking force according to a second braking mode, wherein the braking force of the second braking mode is less than the braking force of the first braking mode. ### Claim 5 (depends on 4) The spool brake device of claim 4 wherein the braking force of the second braking mode is about 50% to about 60% less than the braking force of the first braking mode. ### Claim 6 (depends on 1) The spool brake device of claim 1 wherein the braking force of the first braking mode is about 30% to about 40% less than the braking force of the regular braking mode. ### Claim 7 (depends on 3) The spool brake device of claim 3 wherein the controller is configured to decrease the braking force gradually after the braking force has been set to the first braking mode. ### Claim 8 (depends on 1) The spool brake device of claim 1 wherein the brake unit comprises: a magnet configured to rotate integrally with the spool; a plurality of coils arranged radially outward relative to the magnet; and a switch element electrically coupled to the plurality of coils. ### Claim 9 (depends on 8) The spool brake device of claim 8 wherein the switch element is coupled to the plurality of coils via a rectifier circuit. ### Claim 10 (depends on 8) The spool brake device of claim 8 wherein the switch element further comprises a field-effect transistor. ### Claim 11 (depends on 8) The spool brake device of claim 8 wherein the switch element is electrically coupled to an electric storage element. ### Claim 12 (depends on 1) The spool brake device of claim 1 wherein the controller is configured to control the braking force in the regular braking mode in relation to the rotational speed of the spool, and wherein the controller is configured to control the braking force in the first braking mode in a manner unrelated to the rotational speed of the spool. ### Claim 13 (depends on 1) The spool brake device of claim 1 wherein the detector further comprises: a speed sensor configured to detect the rotational speed of the spool; a speed comparator configured to compare the rotational speed of the spool at time intervals; and an increase/decrease determinator configured to determine if the rotational speed of the spool has increased or decreased between time intervals. ### Claim 14 (depends on 13) The spool brake device of claim 13 wherein the speed sensor further comprises a hall element. ### Claim 15 (depends on 13) The spool brake device of claim 13 wherein the increase/decrease determinator further comprises a casting sensor configured to determine whether the dual bearing reel has cast based on the rotational speed of the spool. ### Claim 16 A dual bearing reel comprising: a reel body; a spool coupled to the reel body; a handle coupled to the reel body; and a spool brake device comprising: a brake unit configured to electrically brake a spool of the spool brake device; a detector configured to detect increase and decrease of the rotational speed of the spool; and a controller configured to control a braking force of the brake unit, wherein the braking force is controlled by the controller based on a detected increase or decrease of the rotational speed of the spool such that when the rotational speed of the spool is detected to be increasing, the controller sets the braking force according to a regular braking mode, and when the rotational speed of the spool is detected to stop increasing, the controller sets the braking force according to a first braking mode, wherein the braking force of the first braking mode is less than the braking force of the regular braking mode.