Multi-channel rotary joint

A multi-channel rotary joint comprising:

• a joint housing;
• a rotator rotatably installed in said joint housing;
• a plurality of elastic seal rings disposed in a row in an axial direction of said rotator so as to be between opposing peripheral surfaces of said joint housing and said rotator, each of said plurality of elastic seal rings being comprised of an annular main body and cylindrical inner and outer peripheral lips that protrude axially from said annular main body and are brought into an elastically pressing contact with said opposing peripheral surface;
• a low-pressure channel space and a high-pressure channel space formed between said opposing peripheral surfaces and sealed by two opposing elastic seal rings of said plurality of elastic seal rings, wherein
• two opposing elastic seal rings that seal said low-pressure channel space are engaged with and supported by one of said opposing peripheral surfaces such that annular grooves between inner and outer peripheral lips of said two opposing elastic seal rings are disposed symmetrically and open into spaces adjacent to said low-pressure channel space, and
• two opposing elastic seal rings that seal said high-pressure channel space are engaged with and supported by one of said opposing peripheral surfaces such that annular grooves between inner and outer peripheral lips of said two opposing elastic seal rings are disposed symmetrically and open into said high-pressure channel space;
• a low-pressure channel and a high-pressure channel provided between said joint housing and said rotator, wherein a fluid lower in pressure than a space adjacent to said low-pressure channel space flows into said low-pressure channel that communicates with said low-pressure channel space, and a fluid higher in pressure than a space adjacent to said high-pressure channel space flows into said high-pressure channel that communicates with said high-pressure channel space;
• and
• said low-pressure channel is a vacuum suction route, and said high-pressure channel is a pressurized fluid supply route.