A runner device for a mobile vehicle includes a runner unit, a brake unit, a transmission unit, and a speed-reduction unit. The runner unit includes a wheel axle, a wheel frame, and a wheel body. The brake unit includes a brake drum disposed on the axle, a drum brake disc rotatably disposed in the brake drum, and at least one movably disposed in the drum brake disc and capable of being driven by centrifugal contact friction. The brake pads of the brake drum. The transmission unit can be used for increasing the rotation speed of the wheel frame and transmitting the rotation speed to the drum brake disc. The speed suppressing unit includes a magnetic brake disc that can move between the drum brake disc and away from the drum brake disc along the wheel axis, and at least one of the magnetic brake discs is provided on the magnetic brake disc and can be used to suppress and slow down the drum brake. Magnetic piece of disk speed. By changing the position of the magnetic brake disc to change the magnetic resistance, the size of the braking resistance can be adjusted, thereby achieving the safety effect of preventing the mobile vehicle from crashing unexpectedly.一種移動載具之轉輪裝置，包含一個轉輪單元、一個剎車單元、一個傳動單元，及一個抑速單元。該轉輪單元包括一支輪軸、一個輪框，及一個輪體。該剎車單元包括一個設置在該輪軸上的剎車鼓、一個可轉動地設置在該剎車鼓內的鼓剎盤，及至少一個可移動地設置於該鼓剎盤內且能被離心驅動而接觸摩擦該剎車鼓的剎車片。該傳動單元可用於將該輪框的轉速遞增並傳動至該鼓剎盤。該抑速單元包括一個可沿著該輪軸在鄰近該鼓剎盤與遠離該鼓剎盤之間移動的磁剎盤，及至少一個設置在該磁剎盤上且能用於抑制減緩該鼓剎盤的轉速的磁性件。藉由移動該磁剎盤位置來改變磁阻力，可調整剎車阻力大小，進而達到防止該移動載具發生突衝意外之安全功效。
