Locking design analyze of central locking casters

As we know due to central locking casters unique brake structure ,they are usually used as medical casters,such as medical bed,medical trolley,liner casters....

At current there are mainly have two types of central brake design.Press force brake,and Locking Gear Brake
Press force brake: The inner side of wheel surface pressed by the brake disc, the wheel locked by friction/pressure.
Advantages: simple structure, low cost
Defects:
1. The brakes will loose after a some time working,sometimes the brake can not lock wheel tightly or can not locked wheel anymore.
2.Need more strength to operate the lock cam, which affects the service life of the central control link system.
Locking gear brake: The wheel is locked through brake gear parts lock the inside gear of the wheel.
Advantage:
1. Once locked, it will not loose again
2. Less operate strength and long service life
Defect:
The structure is complex and the cost is high
Our current design of the control wheel with gear brake design, And the whole wheel is closed ,Our central brake casters enable wheel anti - winding, dust-proof, easy to clean. In addition to this,our wheels use nylon materials to ensure the durability of the wheels.