Work aid for a hairdresser, comprising a mobile frame on which frame a seat surface or at least one storage surface is arranged, wherein the frame comprises at least one castor being arranged rotatably in a fork head, and the castor being arranged on an axle, which axle is arranged insertably in each case with a first end portion on a first fork-shaped receptacle on the fork head and with a second end portion on a second fork-shaped receptacle on the fork head.

A caster has a yoke portion and wheel forks pivotally connected to the yoke portion at a pivot connection. The pivot connection defines a pivot axis. A wheel is rotatably connected to the wheel fork at a wheel axis. A brake lever is operatively connected to the pivot connection to pivot about the pivot axis. The brake lever moves a brake pad between an engaged position and a disengaged position as the brake lever is pivoted about the pivot axis. In the engaged position, brake pad is pressed against the wheel with a cam operatively connected to the brake lever, and wherein the disengaged position, the cam cooperates with the brake pad in a manner such that the brake pad releases from the wheel.

A hollow wheel assembly of a luggage includes a wheel mount, two wheel members, and a hollow shaft. The wheel mount has a shaft sleeve, in which the hollow shaft is received. The wheel members are connected to opposite ends of the hollow shaft for free rotation. The hollow shaft has a vision passage, and the wheel members have a plurality of vision bores, whereby one may see through the wheel members via the vision bores and the vision passages when the wheel members are rotating.

A universal caster is provided that, with a hand truck, for loading and transporting a heavy substance. The universal caster includes a lower stage turning part A being mounted to an upper stage supporting shaft in the upper stage turning part B, thereby being made turnable with respect to the upper stage turning part; and a universal metal fitting that pivotally supports a wheel, being mounted to a lower stage supporting shaft in the lower stage turning part, thereby being made turnable with respect to the lower stage turning part, the lower stage supporting shaft being disposed in a displaced manner in a horizontal direction from the upper stage supporting shaft, and the wheel being supported by the wheel shaft through one or a plurality of rows of spiral springs.

A hollow wheel assembly of a luggage includes a wheel mount, two wheel members, and a hollow shaft. The wheel mount has a shaft sleeve, in which the hollow shaft is received. The wheel members are connected to opposite ends of the hollow shaft for free rotation. The hollow shaft has a vision passage, and the wheel members have a plurality of vision bores, whereby one may see through the wheel members via the vision bores and the vision passages when the wheel members are rotating.

A trolley cart wheel assembly includes a wheel fork formed of two spaced ring-shaped side members respectively having locating holes circumferentially spaced thereon; a wheel disposed between the side members and including an annular base having balls disposed on a circumferential surface thereof in a staggered manner and first locking holes provided on two side walls thereof, a rim covering the balls, a tire covering the rim, and two locating rings disposed on two lateral sides of the annular base to limit the rim between them and being provided with radial notches, such that screws can be extended through the radial notches, the first locking holes and the locating holes to lock the wheel fork, the annular base and the locating rings together; and two wheel covers being provided on respective inner wall surface with axially projected hooks adapted to hook onto inner wall surfaces of the side members.