Position-adjustable brake unit for a dual-purpose roller skate

A position-adjustable brake unit for a dual-purpose roller skate, said brake unit being fixedly mounted to a top of an open-bottomed cavity provided at a lower side of a sole of said roller skate, either independently or along with position-adjustable wheel units of said roller skate, said dual-purpose roller skate functioning like a roller skate when said brake unit and said wheel units are in a lowered position, and like an ordinary shoe when said brake unit and said wheel units are in a lifted position;

• said position-adjustable brake unit comprising a base, a brake support, a brake block, and a stop lever;
• said base including a horizontal portion that is screwed to the top of said cavity on said sole, and two opposite downward extended vertical plates, namely, a front and a rear vertical plate;
• said front and said rear vertical plates being correspondingly provided at a predetermined position with a shaft hole each, said rear vertical plate being provided at a lower part of two lateral sides with two rearward extended first lugs and said front vertical plate being provided at a lower part of one lateral side with a rearward extension, and an opening being provided on said base at an area connecting said horizontal portion and said rear vertical plate;
• said brake support being a substantially rectangular frame having two upward extended vertical wall portions opposite to each other, namely, a front and a rear wall portion, said front and said rear wall portions being correspondingly provided at a predetermined position with a shaft hole each, and at a top edge and one lateral edge with a top and a lateral notch, respectively;
• said brake support being pivotally connected to said base to locate between said two vertical plates by extending a shaft through said shaft holes on said two vertical plates and said two vertical wall portions;
• a first torsion spring being put around said shaft to locate between said two wall portions so as to normally elastically push said brake support downward;
• said brake block being connected to a lower end of said brake support to forward project therefrom and move along with said brake support;
• and
• said stop lever including a horizontal top portion and a vertical portion downward extended from a rear edge of said top portion, said vertical portion being provided at an upper part of two lateral sides with two forward extended second lugs, said stop lever being connected to said base to locate between said two first lugs by extending a pin through said first and said second lugs, such that said top portion forward extends into said opening near the top of said base, a second torsion spring being put around said pin to locate between said two second lugs so as to normally elastically pull said top portion into said opening of said base to selectively engage with either said top or said lateral notch on said brake support;
• whereby by depressing said vertical portion of said stop lever to pivotally turn said stop lever about said pin, said top portion of said stop lever is caused to disengage from said top or said lateral notch on said brake support, allowing said brake support to be shifted between a lowered position, in which said top portion of said stop lever engages with said top notch of said brake support and said brake block is exposed from said cavity, and a lifted position, in which said top portion of said stop lever engages with said lateral notch of said brake support and said brake block is retracted into said cavity.