Levers 2 and 6 turn about fixed axes A and B and have shoes a which embrace brake drum 3. Link 5 has screws b and d with right- and left-hand threads and is connected by screw pairs C and D to links 1 and 4. Links 2 and 6 are connected by turning pairs C and D to links 1 and 4. Shoes a are pressed against drum 3 to apply the brake by turning link 5 about axis x-x.
$2267$LS,Br$