A robot main body is provided with a protection cover. The robot main body can be swung by a rotary pipe shaft holding a wire feed device and including a hollow portion and is structured such that a connecting cable and/or a gas hose are guided through the hollow portion of the rotary pipe shaft and are then guided through the forearm portion and base portion thereof. The protection cover covers the portions of the connecting cable and/or gas hose ranging from the connecting portion of the wire feed device and connecting cable and/or gas hose to the rotary pipe shaft.