Gear rack is a special gear whose teeth are distributed about the strip.
1. The basic concept:
The rack can be divided into a spur gear rack and a helical gear rack, which are paired with a spur gear and a helical gear, respectively; the tooth profile of the rack is usually a straight line instead of an involute (planar for the tooth surface) , equivalent to the indexing circle radius is normally infinite cylindrical gear.
2. The main features:
(1) Because the tooth profile of the rack is right, each point on the tooth profile has the same pressure angle and is equal to the inclination position of the tooth profile. This angle is called the tooth angle and the standard value is 20°.
(2) The same pitch and modulus are given on the straight lines parallel to the top line.
(3) A series parallel to the very best type of the tooth and having a tooth thickness add up to 
the width of the tooth groove is called a dividing range (middle line), which really is a reference range for calculating how big is the rack.
3. The main parameters:
Groove width, high tooth tip, high root height, tooth elevation, tooth thickness, root radius, etc.
4. The decision of parameters:
(1) Whether the gear is beating, the entire tooth depth, the normal normal line, the tooth path is qualified, the tooth pitch is poor, and the circumferential section mistake has gone out of tolerance.
(2) If the installation distance following the gears and racks are installed is suitable.
(3) The rack and gear meshing Taper Lock Pulley clearance should be 0.25* modulus.
(4) Whether the full tooth depth, runout, and common normal line of the rack are qualified.
5. Processing methods:
Gear rack and pinion machining method:
(1) hobbing
(2) gear shaping
(3) shaving
(4) grinding teeth
(5) molars
What is a gear rack?
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