Planetary speed reducer with small tooth difference, in-vehicle display, and vehicle

A planetary reducer with small tooth difference, comprising:

• a reducer housing, an input shaft, a cycloidal gear, an output flange, and a plurality of pin shafts;
• wherein the reducer housing comprises an inner gear ring and the reducer housing sleeved over the input shaft;
• the input shaft has an eccentric cam;
• the cycloidal gear is mounted on the eccentric cam via an arm bearing and meshes with the inner gear ring;
• the cycloidal gear is provided with a plurality of pin holes distributed in a circumferential direction thereof;
• the reducer further comprises a support frame, the support frame having a central shaft hole;
• the input shaft passes through the central shaft hole;
• and
• each pin shaft passes through the corresponding pin hole respectively and both ends of each pin shaft are connected to the output flange and the support frame respectively.