Angle indicating apparatus capable of positioning at predetermined angles

An angle indicating apparatus capable of positioning at predetermined angles, comprising:

• a rod member;
• an indicia member mounted pivotally on said rod member about a pivot axis, said indicia member including a base plate and a stop block extending uprightly from one end of said base plate, said base plate being formed with a generally semi-circular cutout, said cutout having a straight edge that is proximate to said one end of said base plate, and a curved edge that is connected to said straight edge and that has a curvature centered at said pivot axis, said base plate having a top side provided with angle indicia that are disposed adjacent to said curved edge of said cutout, said base plate being further formed with a curved guide slot that is disposed radially and outwardly of said curved edge of said cutout with respect to said pivot axis, said base plate further having a bottom side disposed on top of said rod member and formed with a plurality of angularly spaced apart positioning grooves, said positioning grooves corresponding respectively to the predetermined angles and being spaced apart at equal radial distances from said pivot axis;
• an indicator mounted on said rod member and disposed in said cutout, said indicator having a pointing end pointing to said angle indicia;
• a spring-loaded tumbler unit mounted on said rod member for engaging removably a selected one of said positioning grooves in said bottom side of said base plate;
• and
• a locking unit that passes through said guide slot and that is operable so as to engage said rod member in order to arrest undesired rotation of said indicia member relative to said rod member.