Abstract
A method and system for indexing moulds using a flaskless moulding machine and a mould conveyor are provided. The method comprises: (i) forming one or more moulds, each of the one or more moulds being added to the mould string while the mould string is stationary by being brought into contact with the mould string. Once the one or more moulds has been added to the mould string, the method continues (ii) by advancing the mould string, in a single continuous motion, a distance corresponding to the sum of the thicknesses of the one or more moulds, wherein (1) the moulding machine assists the mould conveyor in advancing the mould string during a first part of the distance, and (2) the mould conveyor advances the mould string a second part of the distance, corresponding to the remainder of the distance, without assistance from the moulding machine.
Claims
1. A method of indexing moulds using a flaskless moulding machine for producing moulds and a mould conveyor for carrying and advancing a mould string produced from a plurality of said moulds received by the mould conveyor from said flaskless moulding machine, said flaskless moulding machine comprising a pressure piston, the method comprising the steps of: i. forming one or more moulds, one at a time, using said flaskless moulding machine, each of said one or more moulds being added to said mould string while said mould string is stationary, by being brought into contact with said mould string subsequently to being produced by said flaskless moulding machine, and, once said one or more moulds have been produced and added to said mould string: ii. advancing said mould string, in a single motion, away from said flaskless moulding machine a distance corresponding to the sum of the thicknesses of said one or more moulds using said mould conveyor, wherein said flaskless moulding machine assists said mould conveyor in overcoming the static friction for bringing said mould string in motion by assisting the mould conveyor in advancing said mould string for a first part of the distance, the first part being up to 50 percent of the distance, said mould conveyor advances said mould string a second part of said distance, corresponding to the remainder of said distance, without assistance from said flaskless moulding machine, and said pressure piston is retracted for producing one or more further moulds once said mould string has been advanced said first part of said distance so that the pressure piston only travels the first part of said distance, and not the full distance.
2. The method according to claim 1, said flaskless moulding machine further assisting said mould conveyor in accelerating said mould string to a desired speed.
3. The method according to claim 2, said flaskless moulding machine further assisting said mould conveyor in advancing said mould string to a position from which said mould string is to be decelerated for being stationary once said mould string has been advanced said distance.
4. The method according to claim 1, wherein said one or more moulds are added to said mould string by said flaskless moulding machine.
5. The method according to claim 1, wherein at least a last one of said one or more moulds is added to said mould string by said flaskless moulding machine and wherein the remainder of said one or more moulds are added to said mould string by first being moved by said flaskless moulding machine to an intermediate position between said flaskless moulding machine and the mould string, and then by being moved from said intermediate position into contact with said mould string by said mould conveyor.
6. The method according to claim 1, further comprising using a core setter capable of setting cores in one or more positions along the mould string for setting a core in a mould cavity of each of said one or more moulds after each of said one or more moulds has been added to said mould string.
7. The method according to claim 5, each of said remainder of said one or more moulds, while being moved from said intermediate position, being moved to a core setting position by said mould conveyor, the method further comprising using a core setter capable of setting cores at said core setting position for setting a core in a mould cavity of each of said remainder of said one or more moulds while each of said remainder of said one or more moulds is at said core setting position, before each of said remainder of said one or more moulds is moved into contact with said mould string by said mould conveyor.
8. The method according to claim 1, said mould conveyor comprising moveable mould retainers for engaging and moving a single mould of said one or more moulds, and a transport system for engaging and moving a second plurality of moulds in said mould string, for advancing said mould string said distance.
9. The method according to claim 1, said mould conveyor further comprising stationary mould retainers for selectively keeping said mould string stationary by engaging a last mould of said mould string, the method further comprising the steps of: engaging said last mould while performing step i, and releasing said last mould prior to performing step ii.
10. The method according to claim 2, wherein said one or more moulds are added to said mould string by said flaskless moulding machine.
11. The method according to claim 3, wherein said one or more moulds are added to said mould string by said flaskless moulding machine.
Description
(1) The invention and its many advantages will be described in more detail below with reference to the accompanying schematic drawings, which for the purpose of illustration show some non-limiting embodiments, and in which:
(2) FIG. 1 shows a sequence of operations of the flaskless moulding machine, the mould conveyor, and the pouring unit in a first embodiment of the method according to the first aspect of the present invention;
(3) FIG. 2 shows a sequence of operations of the flaskless moulding machine, the mould conveyor, and the pouring unit in a second embodiment of the method according to the first aspect of the present invention; and
(4) FIG. 3 shows a sequence of operations of the flaskless moulding machine, the mould conveyor, and the pouring unit in a third embodiment of the method according to the first aspect of the present invention.
(5) In the below description, one or more ‘signs added to a reference number indicates that the element referred to has the same or similar function as the element designated the reference number without the ‘sign, however, differing in structure.
(6) Additionally, where useful for discussing two or more identical elements, a subscript Arabic numeral is used to designate such further identical elements.
(7) When further embodiments of the invention are shown in the figures, the elements which are new in relation to earlier shown embodiments have new reference numbers, while elements previously shown are referenced as stated above. Elements which are identical in the different embodiments have been given the same reference numerals, and no further explanations of these elements will be given.
(8) FIG. 1 shows a sequence of operations of a flaskless moulding machine, in its entirety designated the reference numeral 10, moulds, one of which is the last mould and is designated the reference numeral 2, in a mould string 4 on a mould conveyor, in its entirety designated the reference numeral 20, and a pouring unit indicated by arrow 30 in a first embodiment of the method according to the first aspect of the present invention. In this first embodiment the one or more moulds is a single mould.
(9) The flaskless moulding machine 10 comprises a moulding chamber 12, a swingable squeeze plate 14 and a pressure piston 16 carrying a squeeze plate 18. The squeeze plate 18 carries a first pattern plate 6a, while the swingable squeeze plate carries a second pattern plate 6b.
(10) The swingable squeeze plate 14 is moveable for opening the moulding chamber 12, as described further below.
(11) The mould conveyor 20 comprises a moveable mould retainer 22 for gripping and moving the mould 2 or any single mould produced by the flaskless moulding machine 10. The mould conveyor 20 further comprises a stationary mould retainer 24 which can be actuated to clamp down and retain the last mould 2 in position.
(12) In order to advance the mould string 4, the mould conveyor comprises a transport system exemplified by an AMC (Automatic Mould Conveyor) system illustrated by thrust bars 26, which clamps a plurality of moulds in the mould string 4 for advancing the mould string 4. During advancing, the moveable mould retainers 22 also assist by clamping and moving the last mould 2.
(13) Also shown in FIG. 1A is a core setter 40 for setting core(s) 42 in a mould cavity produced by the last mould 2.
(14) In the following Opr. is used as abbreviation for operation.
(15) In FIG. 1A the mould producing procedure starts with Opr. 1, i.e. the sand is shot into the moulding chamber 12 while the moveable mould retainers 22, the stationary mould retainers 24 and the thrust bars 26 of the AMC system are active for engaging the last mould and the mould string 4, respectively. A pouring unit indicated by arrow 30 pours molten metal into one of the moulds in the mould string 4. The core setter 40 sets the core(s) 42.
(16) FIG. 1B shows Opr. 2, during which the pressure piston 16 is activated for squeezing the sand between the swingable squeeze plate 14 and the squeeze plate 18 to form a first mould 2.sub.1 (shown first in FIG. 1D). The swingable squeeze plate 14 can also assist in squeezing the mould. The core setter 40 is starting to move away from the face of the mould 2 after having set the core(s) 42. The moveable mould retainers 22, the stationary mould retainers 24, and the thrust bars 26 of the AMC system remain active and the pouring of the molten metal continues.
(17) FIG. 1C shows Opr. 3, during which the swingable squeeze plate 14 starts to move away from the moulding chamber 12 so as to open the moulding chamber 12 for allowing the now produced first mould 2.sub.1, shown in FIG. 2D, to be ejected from the moulding machine 10. The core setter 40 has cleared the last mould 2 and continues to move out of the way of the swingable squeeze plate 14. The moveable mould retainers 22, the stationary mould retainers 24, and the thrust bars 26 of the AMC system remain active, and the pouring of the molten metal continues.
(18) FIG. 1D shows Opr. 4A short, during which the first mould 2.sub.1, also designated 8, is ejected from the flaskless moulding machine 10 by being pushed by the pressure piston 16. At the same time the moveable mould retainers 22 release the last mould 2 and are transported the length of the last mould (2) towards the flaskless moulding machine 10. The thrust bars 26 of the AMC system have released the plurality of moulds of the mould string 4 and travel with the moveable mould retainers 22 towards the flaskless moulding machine 10. The stationary mould retaining device 24 remains active for holding the last mould 2 and thus the mould string 4 stationary. Pouring continues.
(19) The moveable mould retainers 22 and the thrust bars 26 may be mechanically coupled to move together.
(20) The first mould 2.sub.1 is here to be delivered to the mould string 4 at a position below the swingable squeeze plate 14, i.e. the swingable squeeze plate 14 cannot swing down without hitting the first mould 2.sub.1 when the first mould 2.sub.1 is delivered to the mould string 4.
(21) For the sake of clarity, the core setter 40, which is now outside the path of the first mould 2.sub.1, is not shown in FIGS. 1D-1G.
(22) In FIG. 1E Opr. 4A Short has been completed and the first mould 2.sub.1 has been brought into contact with the last mould 2 by the pressure piston 16, and close up pressure between the first mould 2.sub.1 and the mould string 4 has been built up. The moveable mould retainers 22 and the thrust bars 26 of the AMC system now engage the first mould 2.sub.1 and the mould string 4, respectively. The stationary mould retainers 24 release the mould 2. After this is done, pouring has to stop as indicated by the cross designated 30′ for being ready for the next step, transport of the mould string 4.
(23) In FIG. 1F the pressure piston 16, after bringing the first mould 2.sub.1 into contact with the mould string 4, assists the thrust bars 26 of the AMC system and the moveable mould retainers 22 in advancing the mould string 4 a first part of the distance of one mould thickness that the mould string 4 is to be advanced. The first part may for example correspond to bringing the mould string 4 in motion, i.e. for overcoming the static friction between the mould string and the mould conveyor 20 and/or for overcoming the inertia of the mould string 4 to accelerate it up to speed. Typically the first part of the distance is a small percentage of the full distance of one mould thickness that the mould string 4 is to be advanced before the pressure piston 16 reverses and allows the mould string to be advanced the second part of the distance, i.e. the remainder of the distance by the thrust bars 26 of the AMC system and by the moveable mould retainers 22 on their own.
(24) The effect of the step shown in FIG. 1F is that the production rate is somewhat lowered due to the travel of the pressure piston increasing compared to the DISAMATIC® 2100 technique, however the AMC system with the thrust bars 26 and the moveable mould retainers 22 do not need to be as strong as is required when the thrust bars 26 and the moveable mould retainers 22 are responsible for advancing the mould string 4, which advancing includes overcoming static friction for bringing the mould string 4 in motion, accelerating the mould string to a suitable speed, i.e. overcoming dynamic friction and inertia, and advancing it the distance on its own. Hence the risk of getting gaps between the last moulds in the mould string 4 is significantly reduced.
(25) In FIG. 1G Opr. 5 Short is performed wherein the pressure piston 16 has released the first mould 2.sub.1 and is now retracting into the ready position for producing a new mould. The release is done on the “fly”. The moveable mould retainers 22 and the thrust bars 26 of the AMC system now advance the mould string 4 the second part of the distance on their own without assistance from the pressure piston 16.
(26) In FIG. 1H the swingable squeeze plate 14 is moving in to close the moulding chamber 12 while the core setter 40 is moving in to set the core(s) 42.sub.1. The moveable mould retainers 22, the stationary mould retainers 24 and the thrust bars 26 of the AMC system remain active for engaging their respective moulds 2.sub.1 and 2 and the mould string 4 while pouring has been restarted after the mould string 4 has stopped.
(27) Following FIG. 1H the cycle will start over from FIG. 1A.
(28) FIG. 2 shows a sequence of operations of the flaskless moulding machine 10′, the mould conveyor 20′, and the pouring unit 30 in a second embodiment of the method according to the first aspect of the present invention. Here the number of moulds is two, compared to being one in FIG. 1. The pouring unit here pours two moulds at the same time as illustrated by the arrow 30 and the additional arrow 30.sub.1.
(29) In FIG. 2A Opr. 1, is being performed. In this operation, sand (not shown) is shot into the moulding chamber 12, while the core setter 40 is setting core(s) 42 in the mould cavity. Further the moveable mould retainers 22 and the stationary mould retainers 24 are actively holding the last mould 2, and thereby the mould string 4, in position and preventing it from moving back. The thrust bars 26 of the AMC system are also active holding the mould string 4 in position. Molten metal is poured simultaneously into two mould cavities as indicated by the arrows 30 and 30.sub.1.
(30) FIG. 2B shows Opr. 2, during which the pressure piston 16 is activated for squeezing the sand between the swingable squeeze plate 14 and the squeeze plate 18 to form a first mould 2.sub.1 (shown first in FIG. 2D). The swingable squeeze plate 14 can also assist in squeezing the mould. The core setter 40 is starting to move away from the face of the mould 2 after having set the core(s) 42. The moveable mould retainers 22, the stationary mould retainers 24, and the thrust bars 26 of the AMC system remain active and the pouring of the molten metal continues.
(31) FIG. 2C shows Opr. 3, during which the swingable squeeze plate 14 starts to move away from the moulding chamber 12 so as to open the moulding chamber 12 for allowing the now produced first mould 2.sub.1, shown in FIG. 2D, to be ejected from the moulding machine 10. The core setter 40 has cleared the last mould 2 and continues to move out of the way of the swingable squeeze plate 14. The moveable mould retainers 22, the stationary mould retainers 24, and the thrust bars 26 of the AMC system remain active, and the pouring of the molten metal continues.
(32) FIG. 2D shows Opr. 4A Long, during which the first mould 2.sub.1, also designated 6A, is ejected from the flaskless moulding machine 10 by being pushed by the pressure piston 16. At the same time the moveable mould retainers 22 release the last mould 2 and are transported the length of the last mould (2) towards the flaskless moulding machine 10. The thrust bars 26 of the AMC system have released the plurality of moulds of the mould string 4 and travel with the moveable mould retainers 22 towards the flaskless moulding machine 10. The stationary mould retaining device 24 remains active for holding the last mould 2, and thus the mould string 4, stationary. Pouring continues.
(33) The moveable mould retainers 22 and the thrust bars 26 may be mechanically coupled to move together.
(34) The first mould 2.sub.1 is pushed by, e.g. under, the swingable squeeze plate 14. For the sake of clarity the core setter 40, which is now outside the path of the mould 2.sub.1, is not shown in FIGS. 2D-F.
(35) In FIG. 2E Opr. 4A Long is finished and the first mould 2.sub.1 has been brought to a first delivery position, marked with the arrow designated A, and into contact with the last mould 2, i.e. the first mould 2.sub.1 has been added to the mould string 4, by the pressure piston 16. The first delivery position A in FIG. 2E is positioned so that the swingable squeeze plate 14 can swing down without hitting the first mould 2.sub.1. The moveable mould retainers 22 now engage the first mould 2.sub.1 while the thrust bars 26 of the AMC system now engage a plurality of the moulds of the mould string 4 including the last mould 2. The stationary mould retainers 24 remain active for holding the last mould 2. Pouring continues.
(36) FIG. 2F shows Opr. 5 Long, in which the pressure piston 16 is retracted into the flaskless moulding machine 10 into a ready position for forming the second mould 2.sub.2. The moveable mould retainers 22 and the stationary mould retainers 24 continue gripping their respective moulds 2.sub.1 and 2. The moveable mould retainers 22, by gripping the first mould 2.sub.1, prevent that the first mould 2.sub.1 is pulled away from the mould string 4 by the pressure piston 16 due to the friction between the first pattern plate 6a and the first mould 2.sub.1 being larger than the friction between the first mould 2.sub.1 and the mould conveyor 20. The thrust bars 26 of the AMC system remain active, and pouring continues.
(37) In FIG. 2G, corresponding to Opr. 6, the swingable squeeze plate 14 swings down and moves in to close the moulding chamber again while the core setter 40 approaches the first mould 2.sub.1 for setting the new core(s) 42.sub.1 in its mould cavity. The moveable mould retainers 22, the stationary mould retainers 24 and the thrust bars 26 of the AMC system remain active for engaging their respective moulds 2.sub.1 and 2 and the mould string 4 while pouring continues.
(38) In FIG. 2H the mould producing procedure starts over with Opr. 1, i.e. the sand is shot into the moulding chamber 12 while the moveable mould retainers 22, the stationary mould retainers 24 and the thrust bars 26 of the AMC system remain active for engaging their respective moulds 2.sub.1 and 2 and the mould string 4 while pouring continues. The core setter 40 sets the core(s) 42.sub.1.
(39) In FIG. 2I Opr. 2 is repeated for forming a second mould 2.sub.2 as described above with reference to FIG. 2B. The moveable mould retainers 22, the stationary mould retainers 24 and the thrust bars 26 of the AMC system remain active for engaging their respective moulds 2.sub.1 and 2 and the mould string 4 while pouring continues. The core setter 40 is starting to move away from the face of the mould 2 after having set the core(s) 42.sub.1.
(40) In FIG. 2J Opr. 3 is repeated as described above with reference to FIG. 2C. The moveable mould retainers 22, the stationary mould retainers 24 and the thrust bars 26 of the AMC system remain active for engaging their respective moulds 2.sub.1 and 2 and the mould string 4 while pouring continues. The core setter 40 has cleared the first mould 2.sub.1 and continues to move out of the way of the swingable squeeze plate 14.
(41) In FIG. 2K Opr. 4A Short is performed. This operation differs from operation 4A Long described above with reference to FIG. 1D in that the second mould 2.sub.2 is to be deposited at a second delivery position one mould thickness closer to the flaskless moulding machine 10 than the first delivery position A. This second delivery position is below the swingable squeeze plate 14, i.e. the swingable squeeze plate 14 cannot swing down without hitting the second mould 2.sub.2 when the second mould 2.sub.2 is in the second delivery position.
(42) As with Opr. 4A Long, the moveable mould retainers 22 release the mould 2.sub.1 and move one mould thickness closer to the flaskless moulding machine 10 for gripping the second mould 2.sub.2. The thrust bars 26 of the AMC system release the mould string 4 and also follow the moveable mould retainers 22 towards the flaskless moulding machine 10. The stationary retaining device 24 remains active for holding the last mould 2 and the mould string 4 stationary. Pouring continues.
(43) For the sake of clarity, the core setter 40, which is now outside the path of the mould 2.sub.2, is not shown in FIGS. 2K-N.
(44) In FIG. 2L Opr. 4A Short has been completed and the second mould 2.sub.2 has been brought to the second delivery position and into contact with the mould 2.sub.1 by the pressure piston 16, and close up pressure between the second mould 2.sub.2 and the mould string 4 has been built up. The moveable mould retainers 22 and the thrust bars 26 of the AMC system now engage the second mould 2.sub.2 and the mould string 4, respectively. The stationary mould retainers 24 release the mould 2. After this is done, pouring has to stop as indicated by the crosses designated 30′ and 30′.sub.1 for being ready for the next step, transport of the mould string 4.
(45) FIG. 2M corresponds to FIG. 1F, the difference being that the mould string 4 is now to be advanced the distance of two mould thicknesses, in contrast to one mould thickness in FIG. 1F. Thus in FIG. 2M the pressure piston 16, after bringing the second mould 2.sub.2 into contact with the mould string 4, assists the thrust bars 26 of the AMC system and the moveable mould retainers 22 in advancing the mould string 4 a first part of the distance of two mould thicknesses that the mould string 4 is to be advanced. In the second embodiment shown in FIG. 2 the first part of the distance is typically the same or similar absolute distance, however, due to the distance that the mould string 4 is to be advanced now being doubled, the first part will be a smaller proportion of the total distance that the mould string 4 is to be advanced.
(46) In FIG. 2N Opr. 5 Short is performed which differs from Opr 5 Long shown in FIG. 2F in that, as the pressure piston 16 is retracted towards the ready position, as in FIG. 1F, the moveable mould retainers 22 and the thrust bars 26 of the AMC system advance the mould string 4 on their own by gripping and advancing the second mould 2.sub.2 as well as the mould string 4 the second part of the distance corresponding to two mould thicknesses. This movement of the mould string 4 is continued in FIG. 2O. Furthermore, Opr. 5 Short differs from Opr. 5 Long in that the pressure piston 16 has to travel a shorter distance to get back into the moulding chamber 12.
(47) The overlap between the swingable squeeze plate 14, the second mould 2.sub.2, and the pressure piston 16 depends on the speed of the swingable squeeze plate 14, the speed of the second mould 2.sub.2, i.e. the speed of the mould string 4, the thicknesses of the moulds 2, 2.sub.1, 2.sub.2, and the speed of the pressure piston 16. As the thickness of the moulds increases, longer transport times are needed.
(48) FIG. 2O shows a modified Opr. 6, in which the swingable squeeze plate 14 starts to move in to close the moulding chamber 12, and the core setter 40 starts to move in to set the core(s) 42.sub.2 in the second mould 2.sub.2. In FIG. 2O the movable mould retainers 22 and the thrust bars 26 of the AMC system still have to advance the mould string 4 the distance of about half of a mould thickness before the stationary mould retainers 24 may engage the second mould 2.sub.2 and the procedure is repeated from FIG. 2A. The difference from the standard opr. 6 is that the mould string 4 is advanced during the modified opr. 6.
(49) During the operations shown in FIGS. 2L to 2O pouring is stopped; however pouring may be started again as soon as the movement of the mould string 4 is finished as shown in FIG. 2A.
(50) The AMC system represented by the thrust bars 26 may be supplanted by, or combined with a PMC (Precision Mould Conveyor) system, and/or a SBC (Synchronized Belt Conveyor) system, or any other suitable transport system.
(51) As is clear from FIG. 2 a very long available pouring time is achieved. At the same time the time for forming the first and second moulds 2.sub.1 and 2.sub.2 is kept short.
(52) Additionally, as the mould string 4 is stationary when forming and ejecting the second mould 2.sub.2, this second mould 2.sub.2 does not have to be brought to the first delivery position A, rather it is only brought to the second delivery position, which is closer to the flaskless moulding machine 10, thereby further decreasing the total travel of the pressure piston 16. This applies to every other second mould produced.
(53) As the double cycle has been finished, the process starts over, the second mould (2.sub.2) now being the last mould 2 on FIG. 2A and the cores 42.sub.2 being 42 shown in FIG. 1B.
(54) FIG. 3 shows a sequence of operations of the flaskless moulding machine 10″, the mould conveyor 20″, and the pouring unit 30 in a third embodiment of the method according to the first aspect of the present invention. Here again the number of moulds is two.
(55) The third embodiment differs from the second embodiment as follows:
(56) In FIG. 3C a modified Opr. 3 is performed. This operation differs from the Opr. 3 shown in FIG. 2C in that the moveable mould retainers 22 already now start to move towards the flaskless mould machine while the thrust bars 26 of the AMC system remain active. Here the moveable mould retainers 22 and the thrust bars 26 can move in relation to each other. The stationary mould retainers 24 remain active and pouring continues.
(57) In FIG. 3D Opr. 4A Short has been performed. Thus, instead of bringing the first mould 2.sub.1 to the first delivery position A, as in FIG. 2D, the pressure piston 16 has only brought the first mould 2.sub.1 to a first intermediate position in which the first mould 2.sub.1 is spaced apart from the mould string 4. As the first mould 2.sub.1 is brought to the first intermediate position, the moveable mould retainers 22 reach the first mould 2.sub.1 and engage the first mould 2.sub.1 by gripping the first mould 2.sub.1.
(58) As can be seen in FIG. 3D, the first intermediate position is positioned below the swingable squeeze plate 14.
(59) In FIG. 3E a modified version of Opr. 5 Short is performed, whereby the pressure piston 16 is retracted towards the ready position and the first mould 2.sub.1 is brought into contact with the mould 2 by being gripped and moved towards the mould string 4 by the moveable mould retainers 22.
(60) FIG. 3F shows the first mould 2.sub.1 just prior to being brought into contact with the mould string 4.
(61) In FIG. 3K a modified version of the operation shown in FIG. 2K is shown. In this modified version the thrust bars 26 of the AMC system release and move two mould thicknesses closer to the flaskless moulding machine 10 while the movable mould retainers 22 also release and move one mould thickness closer to the flaskless moulding machine 10, i.e. the thrust bars 26 of the AMC system move at a higher speed, indicated with a longer arrow, than the moveable mould retainers 22 so that the movable mould retainers 22 and the thrust bars 26 of the AMC system end up at their end positions at the same time.
(62) The rest of the sequence is the same as in the second embodiment.
(63) This third embodiment of the method has the advantage that the travel of the pressure piston 16 is further reduced because it only brings the first mould 2.sub.1 to the first intermediate position, i.e. Opr 4A is short in each of the cycles in the double cycle of the flaskless moulding machine 10″ and the mould conveyor 20.
(64) As the double cycle has been finished, the process starts over, the second mould (2.sub.2) now being the last mould 2 on FIG. 3A and cores 42.sub.2 being 42 on FIG. 3B.
(65) In FIG. 3, cores 42, 42.sub.1 and 42.sub.2 are set by the core setter 40 in two different positions along the mould conveyor 20 as shown on FIGS. 3A and 3H.
(66) For the sake of clarity, the core setter 40 is not shown in FIGS. 3D-F and 3K-M
(67) In the FIGS. 2-3, two moulds are produced and added to the mould string 4, whereafter the mould string 4 is advanced a distance corresponding to two mould thicknesses. The method according to the first aspect of the present invention may however also be used for producing more than two moulds and advancing the mould string 4 a distance corresponding to the sum of thicknesses of the more than two moulds.
LIST OF PARTS WITH REFERENCE TO THE FIGURES
(68) A. Arrow indicating first delivery position 2. Last mould 2.sub.1. First mould 2.sub.2. Second mould 4. Mould string 6a. First pattern plate 6b. Second pattern plate 10. Flaskless moulding machine 12. Moulding chamber 14. Swingable squeeze plate 16. Pressure piston 18. Squeeze plate 20. Mould conveyor 22. Movable mould retainers 24. Stationary mould retainers 26. Thrust bars of AMC system 30. Arrow indicating pouring into one mould 30.sub.1. Arrow indicating pouring into another mould 30′. Cross indicating non-pouring into one mould 30′.sub.1. Cross indicating non-pouring into another mould 40. Core setter 42. Cores 42.sub.1. Cores 42.sub.2. Cores
