Method and system for producing sand moulds

Method for the stepwise production and advancing of sand mould parts in a mould-string foundry plant comprising a station for making mould parts, a pouring station and a conveyor for stepwise advancing of mould parts from said station for making mould parts towards said pouring station, said conveyor comprising a first part that is movable to displace mould parts from the station for making mould parts towards the pouring station, the method comprising producing a plurality of mould parts in the station for making mould parts and placing said mould parts on the conveyor in order to form a mould string on the conveyor, and forwarding the mould parts towards the pouring station using the conveyor, the method comprising the steps of, repetitively and sequentially,

• (a) producing a first mould part of a pair of two subsequent mould parts;
• (b) placing said mould part on the conveyor;
• (c) producing a second mould part of said pair of two subsequent mould parts;
• (d) placing also said second mould part on the conveyor;
• (e) optionally producing at least one further mould part and placing said further mould part on the conveyor;
• (f) displacing the mould string a distance corresponding to at least two mould part widths, so as to position at least two new moulds to be filled in correspondence with the pouring station, wherein step (f) is carried out by displacing said first part of the conveyor;
• wherein the station for making mould parts includes a mould part making apparatus comprising a moulding chamber in which mould parts are made by pressing sand between a front plate and a rear plate, said rear plate being horizontally displaceable with a stroke so as to push a finished mould part out of the moulding chamber and onto the conveyor, wherein during steps (a)-(e), the rear plate is repetitively displaced with the same stroke.

Method for the stepwise production and advancing of mould parts in a mould-string foundry plant, said plant comprising a station for making mould parts, a pouring station and a conveyor for stepwise advancing of mould parts from said station for making mould parts towards said pouring station, said conveyor comprising a first part that is movable to displace mould parts towards the pouring station, the method comprising producing a plurality of mould parts in the station for making mould parts, and placing said mould parts on the conveyor in order to form a mould string on the conveyor, and forwarding the mould parts towards the pouring station using the conveyor, said conveyor further being associated with first retaining means and second retaining means, wherein the method includes the steps of, repetitively and sequentially,

• (i)- producing a mould part,
• (ii)- placing said mould part on the conveyor in contact with a preceding mould part of a string of moulds parts,
• (iii)- displacing the string of mould parts a distance corresponding to one mould part width so as to position a first new mould to be filled in correspondence with the pouring station, by displacing the first part of the conveyor in a horizontal direction towards said pouring station, and optionally pushing the mould string with a rear plate of the station for making mould parts;
• (iv)- returning said first part of the conveyor towards the station for making mould parts a distance corresponding to one mould part width, while optionally retaining the mould string using said second retaining means;
• (v)- once again displacing the string of mould parts a distance corresponding to one mould part width so as to position a second new mould to be filled in correspondence with the pouring station, by once again displacing the first part of the conveyor in said horizontal direction towards said pouring station;
• (vi)- optionally, repeating steps (iv) and (v);
• (vii)- retaining the mould string using said first retaining means or said second retaining means so as to prevent mould parts from being displaced towards the station for making mould parts during pouring into the moulds, and beginning pouring into at least two moulds at the pouring station;
• (viii)- producing at least one mould part and placing said mould part on the conveyor in contact with the mould part produced in step (i), and optionally retaining said mould part produced in step (viii) by using said second retaining means.