1. In a conveyor comprising a track having two channel section portions which extend side-by-side with their open mouths presented towards each other and a trolley having a body and a plurality of load bearing wheels which run inside the channel section portions of the track and support the body from the track, the improvement wherein: the trolley comprises carrier means, the load bearing wheels are mounted on the carrier means for rotation relative thereto about respective axes, the body has a contact surface which faces outwardly from the body in a direction along the track and transverse to the axis of one of said load bearing wheels, the carrier means engages with said contact surface of the body, and releasable retaining means is provided for holding the carrier means in engagement with said surface of the body, whereby, when the retaining means is released, the carrier means can be Withdrawn from the body in a direction parallel to the length of the track.

1. In a conveyor comprising a track having two channel section portions which extend side-by-side with their open mouths presented towards each other and a trolley having a body and a plurality of load bearing wheels which run inside the channel section portions of the track and support the body from the track, the improvement wherein: the trolley comprises carrier means, the load bearing wheels are mounted on the carrier means for rotation relative thereto about respective axes, the body has a contact surface which faces outwardly from the body in a direction along the track and transverse to the axis of one of said load bearing wheels, the carrier means engages with said contact surface of the body, and releasable retaining means is provided for holding the carrier means in engagement with said surface of the body, whereby, when the retaining means is released, the carrier means can be Withdrawn from the body in a direction parallel to the length of the track.

3. In a conveyor comprising a track having two channel section portions which extend side-by-side with their open mouths presented towards each other and a trolley having a body and a plurality of load bearing wheels which run inside the channel section portions of the track and support the body from the track, the improvement wherein: the trolley comprises carrier means, the load bearing wheels are mounted on the carrier means for rotation relative thereto about respective axes, the body includes positioning means which defines a slot for receiving the carrier means and for guiding the carrier means in a direction parallel to the length of the track to a predetermined position relative to the body, said slot has an open mouth which faces along the track and releasable retaining means is provided for restraining movement of the carrier means from said predetermined position relative to the body and thereby retaining the carrier means in assembled relation with the body, whereby, when the retaining means is released, the carrier means can be disassembled from the body by movement relative thereto in a direction transverse to said axis.