Brake apparatus, wheel body assembly and rollator

A brake apparatus, comprising:

• a shaft body;
• a housing, sleeved outside the shaft body and configured coaxially with the shaft body, the housing being rotatable relative to the shaft body;
• a magnetic induction mechanism, arranged in the housing to generate resisting force opposite to a rotation direction of the housing to the housing or generate resisting force opposite to a rotation direction of the shaft body to the shaft body by a magnetic field reaction when the housing rotates relative to the shaft body;
• and
• an adjustment mechanism, connected to the magnetic induction mechanism for adjusting a magnitude of the resisting force;
• wherein the adjustment mechanism comprises an adjustment member and at least one resistor, the adjustment member is electrically connected with the magnetic induction mechanism and is provided with a first connection portion, and one end of the at least one resistor is provided with a second connection portion, the adjustment member is capable of moving relative to the resistor, so that the first connection portion is capable of electrically connecting with the second connection portion.