The object of the present invention is to provide a hopper having a simplified structure that can prevent fragments of component parts generated by vibrations and bolts, nuts, etc., that have fallen out of place from intermixing with the articles in the weighing hoppers or on the conveyor of a combination weighing apparatus. A link mechanism for opening and closing a gate is arranged on a plate provided on one side of the box-like body of a pool hopper. A cover that covers the entire link mechanism is provided and the cover is configured such that it can be freely attached to and detached from the box-like body. The cover can be attached to and detached from the box-like body by engaging and disengaging an engaging member of the cover with and from a nut coupled to the box-like body.