2.1 Swivel bracket
The swivel bracket rotates around its own vertical axis as the running direction changes. The wheel axis is misaligned with respect to the bracket axis so that it is easier to manoeuvre the equipment.
“Manoeuvrability” is defined as the ability of the equipment to change direction, while “directionality” refers to the equipment’s ability to maintain a trajectory along a specific direction.
Excessive offset reduces equipment directionality due to “sliding” of the wheel (the “Swimmy” effect).
Swivel brackets can also be equipped with brakes.
The swivel bracket consists of a connecting plate, a fork, a ball race ring, swivel actions, a central pin and, if necessary, a dust seal.
- Fitting plate
The fitting plate is used to connect the bracket to the equipment (four connection holes).
- Wheel support fork
The fork is the piece with the characteristic upside-down “U” shape that supports the wheel. Holes are drilled at the bottom to house the wheel’s axle set, while the swivel actions are inserted in the top.
- Ball race ring
The ball race ring contains the castor’s swivel actions. In special cases, it can also be used only as a dust seal or a guard.
- Swivel actions
Swivel actions allow the plate to rotate on the fork. They consist of a ring of balls in contact between the plate and the fork (called “ball gyro”) lubricated with grease to protect against dust, liquids and other aggressive agents. The bracket load capacity varies significantly according to the type of swivel action being used.
- Central pin
The central pin is the part that joins the plate and the ball race ring. Thanks to the central pin, the plate and the ball race ring form a single piece, while the fork is free to rotate around its
own axis.The pin can:
- be incorporated in the plate, through forming and riveting after assembling the parts;
- be incorporated in the plate, through hot forming on the plate and tightening with a self-locking nut;
- consist of a screw and a nut.
- Dust seal
The dust seal protects the swivel actions of the bracket against dust and solid and medium-grain aggressive agents.