Ordinary cylindrical worm drive

Normal cylindrical worm tooth surface (except ZK-type worm outside) is generally in the lathe turning tools with straight blades car system. Tool according to the different installation location, the processing of the worm tooth surface in a different section of the tooth profile is also different. Depending on the tooth profile curve can be divided into ordinary cylindrical worm Archimedes worm (ZA worm), involutes worm (ZI worm), the normal straight profile worm (ZN worm) and the cone enveloping cylindrical worm (ZK worm) and other four. GB10085-88 and ZK recommended ZI worm two.

Archimedes worm (ZA worm) This worm, the worm axis perpendicular to the plane (i.e., face), the tooth profile for the Archimedean spiral (Figure Archimedes worm), the plane containing the axis tooth profile (i.e., axial tooth profile) as a straight line, the profile angle α0 = 20 °. It can be used in the lathe pole straight blade (when the lead angle γ ≤ 3 °) or pole (when γ> 3 ° pm) turning. Installation tool, the cutting edge of the top must be the axis of the worm, as shown in Figure Archimedes worm. This worm grinding is difficulty when processing large lead angle inconvenience.

Method to straight profile worm (ZN worm) this worm face gear for the extension of involutes profile (Figure <method to the straight profile of the worm>), French side (NN) tooth profile is a straight line. ZN worm is also a straight blade with single-pole or pole lathe turning. The installation tool form shown in Figure <method to straight profile worm> below. This worm is also more difficult to grind.

Involutes worm (ZI worm) This worm's face for the involutes tooth profile (Figure <involutes worm>), so it is equivalent to a small number of teeth (number of teeth equal to the number of worm head), a large helix angle of involutes line of cylindrical helical gear. ZI worm can two straight blades turning in the lathe turning. The top surface of the blade should be tangent to the base cylinder, in which a cutting tool above the worm axis, another tool is lower than the worm axis, as shown in Figure <involutes worm> below. Tool pressure angle should be equal to the base cylinder helix angle worm. This worm can be on a dedicated machine grinding.

Cylindrical cone enveloping worm (ZK worm) this worm is a nonlinear spiral surface. It can not be lathe, milling machine milling system only in the grinder grinding.  In addition to the work piece for the spiral motion, the tool also around its own axis for rotary motion. At this time, cutter (or grinding wheel) rotating surface envelope is the spiral worm tooth surface (Figure <cone enveloping cylindrical worm>), in the II and NN cross sections are on the tooth profile curve (Figure <cone bread network of cylindrical worm>). This ease of grinding worm, the worm high precision applications become more widespread.