GB1593134A - Installation and process for identifying moulds in a founddry line - Google Patents

Description

(54) INSTALLATION AND PROCESS FOR IDENTIFYING MOULDS IN A FOUNDRY LINE (71) We, SOCIETE ANONYME AUTOMOBILES aTRd'IEN, a French Company organised and existing under Article 118 to 150 of the French Law on Commercial Companies, of 117 a 167, Quai Andre Citröen, 75747 Paris Cedex 15, France, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to an apparatus and process for identifying moulds in a continuous or intermittent travel foundry line.

Generally, foundry lines are formed by one or more continuously or intermittently moving loops for moving moulds, carried by chain trucks, which pass through different treatment stations, such as, for example, the placing of the cores, and casting of the liquid material in the moulds.

In some foundry lines, the travel of the chain trucks is intermittent, with a stop of a suitable length at each working station; the casting of the material in the mould takes place then in a fixed station, a casting truck being placed close to a chain truck.

Some foundry lines are of the continuous travel type, which implies casting in a mobile station, the travel of the casting truck being generally slaved to the movement of the chain trucks. In the case of such a continuous travelling line, the operator places the casting truck in a suitable position, by manual control, relative to a chain truck; an automatic control is then engaged so that the casting truck is servo-controlled to follow the chain trucks at the same speed. The operator, freed from controlling the movements of the truck can supervise the casting. He then disconnects the automatic control so as to be able to ensure the filling of another mould.

Generally, several casting trucks, for example two, are provided for alternately supplying the moulds of the chain trucks, except for the periods for filling these casting trucks. During such a period, a single casting truck supplies all the moulds.

The capacity of a casting ladle is such that it is possible to twill a relatively large number of moulds.

Whatever the type of foundry line, intermittent or continuous travel, it appears that the filling of the moulds, from the ladles of the casting trucks, will be carried out by the operator in a relatively anarchic way, as well as possible in the given circumstances, and that it is practically impossible to impose a definite filling order on such an operator.

It is however very important to permanently identify the moulds particularly so as to be able to decide, depending on the quality of the mould, wether to cast in this mould or not; it is also important to know from which casting ladle and from which casting each mould has been filled, so as to be able to decide, after analysis in the laboratory of the material contained in a casting ladle, to accept or reject all the castings from one ladle.

The invention has as its aim, especially, to provide an installation such that it answers better than heretofore the different requirements of practice and partciularly such that it enables, at all times, the moulds and the chain trucks to be identified and the correspondence between the casting trucks and ladles and the chain trucks associated therewith to be known.

According to one aspect of the present invention there is provided apparatus for identifying moulds in a foundry line having a series of chain trucks each carrying at least one mould and travelling over a given path, the length of a chain truck being equal to the pitch of the chain, and at least one casting truck with a casting ladle containing molten material for filling the moulds, the or each casting truck being adapted to be moved along a casting face adjacent a corresponding portion of the path of the chain trucks and to be brought close to a chain truck to fill the mould or moulds carried by the chain truck, the apparatus comprising: means for determining the location of each chain truck comprising an indicium associated with and identifying a corresponding chain truck, a first scale associated with and representing the length of the chain truck having marked thereon nl subdivisions, and a first reading means fixed in a given position for detecting the indicia and marked subdivisions; means for determining the position on the casting face of a casting truck comprising a second scale associated with the casting face graduated in indicia representing numbers separated by intervals proportional to the pitch of the chain, the intervals between neighbouring indicia of the second scale being divided into n2 marked subdivisions and a second reading means for detecting the indicium and locating subdivision marking which corresponds to the position of the casting truck; and first computing means for determining, from the information supplied by the first and second reading means, which chain truck is associated with a given casting truck.

Advantageously, the apparatus comprises a reduced scale representation of a foundry line in which the indicium identifying a corresponding chain truck is provided together with the corresponding first scale on a representation of said chain truck, the second scale extends along a representation of the casting face and the movement of a representation of a casting or chain truck is synchronized with the movement of the corresponding casting or chain truck.

Preferably, the number n1 of subdivisions on the first scale equals number n2 of subdivisions on the second scale. Furthermore, advantageously the number of subdivisions n1 or n2 is ten.

Desirably, the indicia associated with consecutive chain trucks, and consecutive indicia on the second scale, represent consecutive integers and the consecutive subdivision markings on the first and second scales are associated with consecutive numbers.

Also, in the preferred embodiment, the indicia associated with the chain trucks represent numbers whose magnitude increases in a direction opposite to the direction in which the magnitude ot the numbers represented by the indicia on the second scale increases According to a first embodiment, the first reading means is aligned with the origin of the second scale.

According to a second embodiment, the first reading means is aligned with the subdivision marking intermediate the first and second indicia on the second scale.

Advantageously, synchronization of the movement of a casting truck of a foundry line with the movement of a corresponding chain truck in a mobile casting station is controlled by the subdivision markings of the first scale which are read by the first readings means.

Second computing and control means may be provided to address a casting truck to a predetermined chain truck or trucks.

According to a second aspect of the present invention there is provided a process for identifying moulds in a foundry line having a series of chain trucks travelling over a given path, each of which carries at least one mould, the length of a chain truck being equal to the pitch of the chain and at least one casting truck with a casting ladle containing molten material for filling the moulds, the or each casting truck being adapted to be moved along a casting face adjacent a corresponding portion of the path of the chain trucks and to be brought close to a chain truck to fill the moulds carried by the chain truck, the process comprising: determining from a first reading means the location of a chain truck with which is associated an indicium representing an integer and a first scale representing the length of the chain truck and having marked thereon n1 subdivisions, the first reading means detecting the indicium associated with the chain truck and the subdivision marking on the first scale with which it is aligned; determining the position on the casting face of a casting truck with which is associated a second scale graduated in indicia representing integers separated by intervals' proportional to the pitch of the chain, the interval being divided into n2 subdivisions, from a second reading means which reads from the second scale the indicium and subdivision marking corresponding to the position of the casting truck; and using first computing means to calculate from the two readings which particular chain truck is associated with a given casting truck.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 shows schematically a part of a foundry line in which, during a casting operation, a casting truck travels with the chain trucks, incorporating an installation for identifying the moulds according to a first embodiment of the invention; Figure 2 is a diagram illustrating one embodiment of a representation of the foundry line for identifying the moulds; Figure 3 shows schematically part of a foundry line incorporating the first embodiment of the invention in which, unlike the foundry line depicted in Figure 1, the chain trucks travel past a fixed casting truck during the casting operation; Figure 4 shows, schematically a part of a foundry similar to that illustrated in Figure 1, but incorporating a second embodiment of the apparatus according to the present invention; Figure 5 shows diagrammatically a part of a foundry line similar to that shown in Figure 3, but incorporating the second embodiment of the apparatus according to the present invention; and Figure 6 is a diagram illustrating part of a foundry line incorporating the second embodiment of the invention in which foundry line a casting truck moves along a line of motionless chain trucks.

Referring to Figure 1, there can be seen a part of a foundry line I which comprises chain trucks c schematically shown by rectangles for continuous or intermittent travel.

These chain trucks travel along a given path, generally a closed loop, a portion b of which is shown in Figure 1.

Each chain truck carries at least one mould m schematically shown in the drawing. The chain trucks follow one another end to end and the length p of a truck c is e ual to the pitch of the chain.

it will be readily understood that the identification of a chain truck is equivalent to the identification of the mould or of the set of moulds carried by this chain truck.

At least one casting truck A carrying a casting ladle containing molten metal for filling the moulds m is provided. This truck A is adapted to be moved along a casting face f corresponding to a preferably rectilinear part of the path of the chain trucks. This casting truck A may be brought close to a chain truck for filling the mould(s) of the chain truck.

Casting truck A carrying the ladle and the operator's cabin (not shown) travels on rails on the ground. The pouring of a liquid metal into the moulds is carried out by tipping the ladle. A rack S is provided above truck A, along the length of casting face f, for causing a coder L', which will be discussed hereafter, carried by truck A, to travel past a fixed scale g.

The capacity of casting ladle A is such that the moulds of several chain trucks can be filled before it is necessary to refill the casting ladle A. Support means are provided for conveying this truck A to a filling station.

This embodiment of casting truck A is however not limitative. Casting ladles could be provided whose capacity corresponds to a single mould, the ladles being refilled after each casting.

Generally, several casting trucks A, e.g. two casting trucks, are provided for the same foundry line, so as to fill the mould alternately; when one of the casting trucks leaves for refilling, the other truck alone sees to the filling of the moulds of the chain trucks.

Drive means E are provided for driving the chain trucks c, e.g. in the direction of the arrow of Fig. 1, i.e. clockwise.

Means for locating each train truck c as it passes a fixed point H are provided.

These locating means comprise a number for each truck, as can be seen in Fig. 1, the numbers of the trucks shown increase from right to left from 207 to 211, so that these numbers increase when they travel past point H.

These numbers may be associated with the truck in any appropriate form, e.g. in the form of magnetic or optical lettering.

The numbers of the trucks are formed by successive whole numbers, which succeed each other like the chain trucks.

The length p of each truck is itself divided into n1 subdivisions provided with locating marks i. The interval between two successive marks i is then equal to p n1 Advantageously, Oi=10 and marks i are formed by successive figures 1,2 . .. . 9.

These locating marks i are executed in any appropriate form like the numbers of the chain tracks.

Reading means, such as a coder L, are provided at fixed place H to read the number of the chain truck and the locating mark which passes opposite this fixed point. Coder L is connected to computing means D, to which are transmitted the information read by this coder.

It will be readily understood that from the number of the chain truck which happens to be opposite point H, the position of any other chain truck can be deduced since the distribution of these trucks in the foundry line is known.

Means are also provided for indicating the position of the casting truck A along casting face f.

These means are carried above foundry line I and comprise scale g extending along the casting face, graduated with numbers spaced at a pitch equal to pitch p of the chain.

The numbers of scale g are formed by successive whole numbers increasing progressively from left to right, i.e. in the direction of movement of chain truck c; in Fig.

1 the numbers shown are 0,1 . . . 4.

According to the embodiment of Fig. 1, the beginning 0 of scale g is at right angles to fixed point H where coder L reads the numbers and marks of the chain trucks.

Each interval between the numbers of scale g is divided into n2 subdivisions also provided with locating marks i. Preferably, n2 is equal to 10 and the locating marks of scale g, between two numbers, are formed by figures 1 to 9, as shown in Fig. 1.

The numbers and the locating marks of scale g are executed in any appropriate way so as to be able to be read, e.g. in magnetic or optical form as already envisaged for the chain trucks.

Reading means, such as a coder L' are carried by casting truck A so as to read the number and the locating mark of scale g opposite which coder L' happens to be. In the diagram of Fig. 1, coder L' is shown in a position such that it reads the number and the mark of scale g which are at right angles to the left hand end of truck A.

This truck A has been shown having a length equal to that of a chain truck and so equal to pitch p of the chain. It is clear, however, that all the explanations which follow remain valid whatever the length of truck A.

Coder L' is connected to computing means D for transmitting thereto its readings.

The locating marks of the chain trucks enable the relative creep of each truck in relation to starting fixed point H to be distinguished. The locating mark of the subdivision is placed after the number of the truck and forms a fractional figure.

The same goes for the locating marks of scale g of the casting truck, which enables the relative creep of casting truck A in relation to the beginning of the scale to be distinguished.

The computing means D determine, from information supplied by coder L and coder L', the number of the chain truck associated with the casting truck A. In the embodiment of Fig. 1, this determination consists simply in increasing the reading made by coder L' by half a pitch, i.e. by 0.5, then in subtracting this reading thus increased from the reading effected by coder L. In the result of the subtraction, only the whole number which corresponds to the number of the chain truck associated with casting truck A is kept.

A first example of operation of the embodiment of Fig. 1 is given hereafter, for the case where the casting is carried out in a mobile station.

It is recalled that casting truck A is brought, by an operator, beside a chain truck, by a manual control, then, when the relative position of casting truck A and the chain truck seems suitable, the operator engages an automatic control so that the casting truck A is commanded to follow the chain truck at the same speed. The servo-control of the movements of truck A may be achieved by any appropriate means; e.g. a tachymetric dynamo may be driven by the driving means E for the chain trucks to give a signal proportional to the speed of the chain trucks.

This signal is opposed to a second signal corresponding to the speed of movement of casting truck A.

The difference between the two signals gives an error signal proportional to the speed variation. This error signalacts on the motor driving the casting truck A in the direction which tends to equalize the speeds.

This being recalled, the operation will be explained by supposing for example, as shown in Fig. 1, that the operator has brought, by manual control, the casting truck A beside chain truck No. 209; the operator engages the automatic control when the position of truck A in relation to truck 209 seems to him suitable.

We will assume that truck A is perfectly centred, in relation to chain truck 209, at the moment of engaging the automatic control; it is also assumed that the engagement of the automatic control is carried out at the moment when chain coder L reads 210.0, i.e. the moment when the line of separation between chain truck 209 and chain truck 210 passes in front of coder L. At this time, if the installation presents no error, the coder L of the casting truck will read 0.0 on scale g.

Truck A will then move at the same speed as chain truck 209 and coders L and L' will send their information to computing means D.

These computing means add to the reading of coder L' a half-pitch, i.e. 0.5; this sum is then subtracted from the reading of coder L.

Table I shows: - in column I the series of readings carried out by coder L; - in column III the series of readings made by coder L' of the casting truck A; - in column III the shift constant equal to half a pitch, i.e. equal to five locating marks in the example envisaged, which is added to the reading of coder L'; - in column IV the operation for determining the chain truck number associated with the casting truck by the difference between the reading of column I and the sum of columns II and III; - in column V, the result of the operation of column IV; the number of the chain truck associated with the casting truck corresponds to the whole part of the difference, the fractional part of this difference forms a centring indication of the casting truck in relation to the chain truck.

An examination of the different columns shows that the readings of coders L and L' progress simultaneously, so that the identification number of the truck remains equal to 209 and the centring indication equal to 5.

A centring indication equal to 5 corresponds to perfect centring such as shown in Fig. 1; the casting truck A moves while remaining constantly centred in relation to chain truck 209.

TABLE I

I II III Iv V 210.0 0.0 0.5 210.0 - (0.0 + 0.5) = 209.5 210.1 0.1 0.5 210.1 - (0.1 + 0.5) = 209.5 210.2 0.2 0.5 210.2 - (0.2 + 0.5) = 209.5 210.3 0.3 210.3 - (0.3 + 0.5) = 209.5 210.4 0.4 210.4 - (0.4 + 0.5) = 209.5 210.5 0.5 210.5 - (0.5 + 0.5) = 209.5 210.6 0.6 210.6 - (0.6 + 0.5) = 209.5 210.7 0.7 209.5 210.8 08 209.5 210.9 0.9 209.5 211.0 1.0 211.0- (1.0+ 0-5) = 209.5 211.1 0-1 209.5 211.2 0.2 209.5 209.5 212.0 2.0 0.5 212.0 - (2.0 + 0.5) = 209.5 TABLE II

I II III IV V 1.4 2.0 0.5 (323 + 1.4)-(2.0 + 0.5) 321.9 1.5 2.0 0.5 (323 + 1.5)-(2.0 + 0.5) 322.0 1.6 2.0 0.5 (323 +1.6)-(2.0 + 0.5) 322.1 1.6 2.0 0.5 (323 + 1.6)-(2.0 + 0.5) 322.1 1.7 2.0 0.5 (323 + 1.7) - (2.0 + 0.5) 322.2 1.8 2.0 0,5 322.3 1.9 2.0 0.5 322.4 2.0 2.0 0.5 322.5 2.1 2.0 0.5 322.6 2.2 2.0 0.5 322.7 2.3 2.0 0.5 W 322.8 2.4 2.0 0.5 i (323.0 + 2.4) - (2.0 + 0.5) 1 322.9 2.5 2.0 0.5 2.5-(2.0+0.5) 000.0 2.6 2.0 0.5 2.6-(2.0+0.5) 000.1 2.7 2.0 0- 5 2.7-(2.0+0.5) 000.2 In the table, it can be seen that for the position shown in Fig. 1, which corresponds to reading 212.0 by coder L, the reading by coder L' is 2.0 so that after addition of the half-pitch and subtraction, we still find, in column V, the number 209.5 whose whole part 209 corresponds indeed to the chain truck which happens to be at the side of casting truck A.

A deficiency in the centring of casting truck A in relation to the chain truck at the moment of engaging the automatic control, or a deficiency in adjustment of the apparatus itself may cause coder L' of casting truck A to read a locating mark different from 0 at the moment when coder L of the chain trucks reads 210.0.

For example, the coder of the casting truck may read at the initial moment 0.2. This being so, it can be immediately seen in column V that, instead of obtaining the number 209.5, the number 210.0 -- 1(0.11 + 0.5) = 209.3.

The whole number 209 will always correspond to the same truck nutnber; only the centring indication will have varied since in this second case, the centring indication will be equal to 3 indicating a poorer centring than when the indication is equal to 5.

It can be seen that the correct identification of the mould exists as the sum of the cumulated errors remains less than a halfpitch.

In the numerical example of table I, we find the case where the number read by coder L is greater than that read by coder L' of the casting truck.

It may happen that the number read by coder L is less than that read by coder L'.

For determining the number of the chain truck associated with the casting truck, there is then added to the reading of coder L, the total number of chain trucks contained in the closed loop of the foundry line.

A numerical example given with reference to Fig. 3 and to table II will enable this case to be better understood. This numerical example corresponds furthermore to a fixed casting truck A and to chain trucks which travel past beside this casting truck.

The initial reading of coder L is 1.4 whereas the initial reading of coder L' of the casting truck is 2.0, as can be seen from the first line of table II and from Fig. 3. The columns of table II correspond to those of table I.

The number of chain trucks is equal for example to 323, so that the last truck of the loop of the foundry line bears the numbers 322, whereas the following truck, which corresponds to the first truck of the line, bears the number 0.

For all cases where the reading of coder L is less than that of coder L', the number 323 is added to the reading of L before deducting the sum of the reading of L' and the shift constant.

It can be seen, from column V of the table, that the first identification number of the chain truck associated with the casting truck is equal to 321.9.

Referring to Fig. 3, it can be seen that little more than half (six tenths of the length) of casting truck A, is at the side of chain truck No. 321. By only considering the whole number of 321.9, we find effectively 321.

The indication supplied by the identification installation is then satisfactory.

Since the chain trucks continue to advance, whereas the casting truck remains fixed, when coder L reads 1.5 (second line of table II), the number serving as identification will be equal to 322.0 (second line of column V of table II). By only considering the whole number, we obtain number 322 for the chain truck.

It is to be noted that the centring indication equal to nought means that the deficiency in centring is maximum; referring to Fig. 3 and imagining that the chain trucks are moved one subdivision rightwards, so that the reader L reads 1.5, it will be understood that half of the length of casting truck A is at the side of chain truck 322 and the other half at the side of chain truck 321.

At the following subdivision, more than half of truck A will be at the side of chain truck 322. When the reading by coder L becomes equal or greater that that of coder L', we cease to add to the reading of L the total number of the chain trucks to effect directly the subtraction. This situation is produced in the twelfth line of table II.

Computing means D are arranged to effect these operations.

It will be readily understood that it is sufficient to provide conventional electronic comparator means to effect the comparison of the readings made by L and L' and, according to the result of the comparison, to add or not the total number of trucks or, more generally, to effect the operations necessary for determining the chain truck number.

According to a second embodiment, shown schematically in Fig. 4, scale g of the casting face, is shifted by a half-pitch in relation to the position of coder L of the chain trucks.

As can be seen in Fig. 4, the beginning 0 of graduated scale g is offset leftwards in relation to the fixed beginning H where coder L makes its readings; the graduation 0.5 of scale g, corresponding to a half-pitch, is at right angles to coder L.

By adopting this arrangement, coder L' of casting truck A is caused to read a graduation automatically increased by a half-pitch in relation to the case of Figs. 1 and 3.

This being so, computing means D have no longer to effect the preliminary addition of a half-pitch.

These computing means D indicate the chain truck associated with casting truck A by directly carrying out the subtraction of the number and the locating mark of the casting truck, from the number and the locating mark of the chain truck and by only keeping the whole part of the result of this subtraction.

This whole part corresponds to the number of the chain truck in question.

When the reading of coder L' is greater than that of coder L, computing means D add to the reading of coder L the total number of chain trucks contained in the foundry line, as previously explained.

Three numerical examples corresponding to the second embodiment are treated hereafter with reference to Figs. 4 to 6 and tables III to V.

Fig. 4 corresponds to casting carried out in a mobile station, i.e. that the casting truck A moves in synchronism with the chain trucks. TABLE III

II Ill IV 210.0 0.5 210.0 - 0: 5 = 209.5 210.1 0.6 210.1 - 0 6 = 209.5 21n.2 0.7 210.2 - 0.7 = 209.5 210.3 0.8 210.3 - 0.8 = 209.5 210.4 0.9 210.4 - 0.9 = 209.5 210.5 1.0 210.5 - 1.0= 209.5 212.0 2.5 212.0-2.5 = 209.5 TABLE IV

1 1 TABLE V

I II III IV 2.0 1.5 20-1.5= 000.5 2.0 1.6 2.0 - 1.6 = 000.4 2.0 1.7 2.0-1.7= 000.3 2.0 1.8 2.0 - 1.8 = 000.2 2.0 1.9 2.0-1.9= 000.1 2.0 2.0 2.0 - 2.0 = 00D.0 2.0 2.1 (323 + 2) - 2.1 322.9 2.0 2.2 (323 + 2) - 2.2 322.8 2.0 2.3 (323 + 2) - 2.3 322.7 2.0 2.4 (323 + 2) -- 2.4 322.6 2.0 2.5 (323 + 2) - 2.5 322.5 2.0 2.6 (323 + 2) - 2.6 322.4 In the example shown, it has been assumed that the operator has brought, by operating a manual control, casting truck A beside chain truck 209 while making sure that casting truck A is perfectly centred. This placing of casting truck A was effected before chain truck 210 passes in front of coder L. The automatic control was then engaged so that truck A is driven at the same speed as chain truck 209, so as to remain therebeside.

The readings successively carried out by coder L and coder L' when the chain trucks and the casting truck travel past are shown in columns I and II of table III.

When coder L reads 210.0, i.e. when the separation plane between truck 209 and truck 210 passes in front of coder L, because of the shift of the begining of scale g, coder L' of the casting truck A will read 0.5. The determination of the chain truck associated with the casting truck is obtained, as shown in column III of table III, by subtracting column II from column I. The result of this subtraction is shown in column IV. This result 209.5 remains constant when the synchronisation of the movements of the casting truck 30a is correct.

It will be noted, in particular, that Fig. 4 shows the position corresponding to the last line of table IV, in which coder L reads 212.0, whereas coder L' reads 2.5. The difference is equal to 209.5.

The whole part of this difference, i.e. 209, corresponds to the number of the chain truck associated with casting truck A.

Fig. 5, in combination with table IV, shows the case of a foundry line, according to the second embodiment of the invention, in which casting truck A remains fixed and the chain trucks travel past during casting operations.

The columns of table IV correspond to those of table III.

The position shown in Fig. 5, corresponds to the first line of table IV, in which the reading effected by coder L is less than the reading of coder L'. As previously explained with reference to table II and Fig. 3, the total number of the chain trucks of the foundry line, i.e. 323 in the example envisaged, is added to the reading of coder L, appearing in column I of table IV; then the subtraction is effected to determine the number of the chain truck associated with casting truck A.

It can be seen that the first line of table IV corresponds to a discrepancy of centring of half a pitch. As the chain trucks move from left to right in Fig. 5, the centring indication of chain truck 322 improves, passes through value 5 corresponding to perfect centring, then deviates from this value. In fact, chain truck 0 will succeed chain truck 322, beside casting truck A.

When the reading of coder L becomes equal to or greater than the reading of coder L', the determination of the truck associated with the casting truck is carried out by direct subtraction, as in the case of table III.

This situation is to be found again in the last two lines of table IV.

The mould identification installation, according to the invention, may also be suitable in the case where the casting is carried out with a mobile casting truck A, whereas the chain trucks remain motionless.

Fig. 6 and corresponding table V illustrate this possibility in the case of the second embodiment, with the graduated scale g shifted half a pitch.

The position of the mobile casting truck A, shown in Fig. 6 corresponds to the position of the first line of table V, with perfect centring at the side of truck 0.

The preceding explanations enable table V, whose columns correspond to those of tables III and IV, to be read and interpreted without difficulty. On the seventh line of this table, we find again the situation already explained in which the reading of coder L becomes less than that of coaer L'.

All the reading and identification operations of the chain trucks and of the casting truck may be effected on a representation J (Fig. 2) of the foundry line, on a reduced scale. This representation may be formed by an endless belt corresponding to the loop of the foundry line, the chain trucks and the moulds which they carry being shown schematically on this belt; the numbers and locating marks of the chain trucks are also shown on this belt, e.g. in the form of strokes or strips which correspond, according to a code, to the figures and numbers shown in the drawings. The belt is driven in synchronism from the foundry line drive by trans mission means T. The knowledge of the position of a chain truck on the belt enables the position of all the other trucks to be deduced.

The graduated scale for locating the position of casting truck A may possibly also be formed by a representation g', on the same scale as the representation of the foundry line. A perfect correspondence is ensured between the respective positions of the real casting trucks and chain trucks and the represented casting trucks and chain trucks.

The representation of the real foundry line is advantageously disposed for protection in an enclosure.

In the case of casting carried out in a mobile station, the synchronisation of the movement of casting truck A can be achieved by a control by means of locating marks or crenels of the chain trucks read by chain coder L. For example, the slaving of casting truck A to the associated chain truck would be achieved by means of a stepping motor driving casting truck A; this motor would be controlled by chain coder L. In the example shown in the drawings where the subdivisions of the chain trucks are of the same length as the subdivisions of the scale of the casting face g, the reading by coder L of each subdivision would cause a rotation of the motor by a number of steps ensuring a movement of casting truck A of an amplitude equal to that separating two divisions of the chain trucks.

Computing means D may be arranged furthermore so as to address the casting trucks A to predetermined chain trucks, so as to optimise the casting. Thus the filling of the moulds by a given ladle is ensured according to a distribution established beforehand.

The installation of the invention enables the chain trucks associated with the casting trucks to be identified without error as long as the cumulated uncertainties do not exceed half a pitch of the chain which, practically, does not happen.

In the case of a stoppage of the foundry line, we find again, when starting up again, without error, the correct identification.

It will be noted furthermore that the centring indications formed by the fractional figures which follow the identification number of the chain truck, enable, in the case of a mobile station casting line, to evaluate the quality of the synchronisation of the move ments of casting truck A.

In fact, a deficiency of synchronisation will cause a variation of the centring indication, whereas proper synchronisation causes a constant centring indication.

It will be readily understood that modifi cations can be made to the embodiments described, without departing from the scope of the invention. In particular, the numbers n1 and n2 of subdivisions may be different from each other and different from 10, while still remaining whole numbers.

it is recalled that the numbers and the locating marks may be provided, materially, by any appropriate signs such as a stroke of variable length, etc...., a correspondence code being provided between the numbers and figures of the description and drawings and the material signs used.

It can be noted, that in the examples described, the identification of the chain truck associated with the casting truck involved a subtraction of two readings.

According to the circumstances another operation can be used for this determination; if the chain of trucks travelled in the opposite direction, an addition would be used.

In the case for example where the chain is fixed, the use of numbers and locating marks which progress in one direction or in the other may be contemplated.

Generally, it can then be said that the determination of the chain truck associated with the casting truck involves an arithmetical operation (subtraction or addition) which depends on the conditions of numbering (direction of numbering) and operation (direction of movement of the chain).

WHAT WE CLAIM IS: 1. Apparatus for identifying moulds in a foundry line having a series of chain trucks each carrying at least one mould and travelling over a given path, the length of a chain truck being equal to the pitch of the chain, and at least one casting truck with a casting ladle containing molten material for filling

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (13)

**WARNING** start of CLMS field may overlap end of DESC **. shown in Fig. 6 corresponds to the position of the first line of table V, with perfect centring at the side of truck 0. The preceding explanations enable table V, whose columns correspond to those of tables III and IV, to be read and interpreted without difficulty. On the seventh line of this table, we find again the situation already explained in which the reading of coder L becomes less than that of coaer L'. All the reading and identification operations of the chain trucks and of the casting truck may be effected on a representation J (Fig. 2) of the foundry line, on a reduced scale. This representation may be formed by an endless belt corresponding to the loop of the foundry line, the chain trucks and the moulds which they carry being shown schematically on this belt; the numbers and locating marks of the chain trucks are also shown on this belt, e.g. in the form of strokes or strips which correspond, according to a code, to the figures and numbers shown in the drawings. The belt is driven in synchronism from the foundry line drive by trans mission means T. The knowledge of the position of a chain truck on the belt enables the position of all the other trucks to be deduced. The graduated scale for locating the position of casting truck A may possibly also be formed by a representation g', on the same scale as the representation of the foundry line. A perfect correspondence is ensured between the respective positions of the real casting trucks and chain trucks and the represented casting trucks and chain trucks. The representation of the real foundry line is advantageously disposed for protection in an enclosure. In the case of casting carried out in a mobile station, the synchronisation of the movement of casting truck A can be achieved by a control by means of locating marks or crenels of the chain trucks read by chain coder L. For example, the slaving of casting truck A to the associated chain truck would be achieved by means of a stepping motor driving casting truck A; this motor would be controlled by chain coder L. In the example shown in the drawings where the subdivisions of the chain trucks are of the same length as the subdivisions of the scale of the casting face g, the reading by coder L of each subdivision would cause a rotation of the motor by a number of steps ensuring a movement of casting truck A of an amplitude equal to that separating two divisions of the chain trucks. Computing means D may be arranged furthermore so as to address the casting trucks A to predetermined chain trucks, so as to optimise the casting. Thus the filling of the moulds by a given ladle is ensured according to a distribution established beforehand. The installation of the invention enables the chain trucks associated with the casting trucks to be identified without error as long as the cumulated uncertainties do not exceed half a pitch of the chain which, practically, does not happen. In the case of a stoppage of the foundry line, we find again, when starting up again, without error, the correct identification. It will be noted furthermore that the centring indications formed by the fractional figures which follow the identification number of the chain truck, enable, in the case of a mobile station casting line, to evaluate the quality of the synchronisation of the move ments of casting truck A. In fact, a deficiency of synchronisation will cause a variation of the centring indication, whereas proper synchronisation causes a constant centring indication. It will be readily understood that modifi cations can be made to the embodiments described, without departing from the scope of the invention. In particular, the numbers n1 and n2 of subdivisions may be different from each other and different from 10, while still remaining whole numbers. it is recalled that the numbers and the locating marks may be provided, materially, by any appropriate signs such as a stroke of variable length, etc...., a correspondence code being provided between the numbers and figures of the description and drawings and the material signs used. It can be noted, that in the examples described, the identification of the chain truck associated with the casting truck involved a subtraction of two readings. According to the circumstances another operation can be used for this determination; if the chain of trucks travelled in the opposite direction, an addition would be used. In the case for example where the chain is fixed, the use of numbers and locating marks which progress in one direction or in the other may be contemplated. Generally, it can then be said that the determination of the chain truck associated with the casting truck involves an arithmetical operation (subtraction or addition) which depends on the conditions of numbering (direction of numbering) and operation (direction of movement of the chain). WHAT WE CLAIM IS:

1. Apparatus for identifying moulds in a foundry line having a series of chain trucks each carrying at least one mould and travelling over a given path, the length of a chain truck being equal to the pitch of the chain, and at least one casting truck with a casting ladle containing molten material for filling

the moulds, the or each casting truck being adapted to be moved along a casting face adjacent a corresponding portion of the path of the chain trucks and to be brought close to a chain truck to fill the mould or moulds carried by the chain truck the apparatus com prising: means for determining the location of each chain truck comprising an indicium associated with and identifying a correspond ing chain truck, a first scale associated with and representing the length of the chain truck having marked thereon ni subdivisions, and a first reading means fixed in a given position for detecting the indicia and marked subdivisions; means for determining the position on the casting face of a casting truck comprising a second scale associated with the casting face graduated in indicia representing 'numbers separated by intervals proportional to the pitch of the chain, the intervals between neighbouring indicia of the second scale being divided into n2 marked subdivisions and a second reading means for detecting the indicium and locating subdivision marking which corresponds to the position of the casting truck; and first computing means for determining, from the information supplied by the first and second reading means, which chain truck is associated with a given casting truck.

2. Apparatus according to claim 1, and further comprising a reduced scale representation of a foundry line in which the indicium identifying a corresponding chain truck is provided together with the corresponding first scale on a representation of said chain truck, the second scale extends along a representation of the casting face and the movement of a representation of a casting or chain truck is synchronized with the move ment of the corresponding casting or chain truck.

3. Apparatus according to claim 1 or 2, wherein the number n, of subdivisions on the first scale equals the number n2 of sub divisions on the second scale.

4. Apparatus according to claim 3, wherein the number of subdivisions n1 or n2 is ten.

5. Apparatus according to claim 1, 2, 3 or 4, wherein the indicia associated with consecutive chain trucks, and consecutive indicia on the second scale, represent consecutive integers and wherein the consecutive subdivision markings on the first and second scales are associated with consecutive numbers

6. Apparatus according to any one of claims 1 to 5 wherein the indicia associated with the chain trucks represent numbers whose magnitude increase in a direction opposite to the direction in which the magnitude of the numbers represented by the indicia on the second scale increases.

7. Apparatus according to any preceding claim, wherein the first reading means is aligned with the origin of the second scale.

8. Apparatus according to any one of claims 1 to 6, wherein the first reading means is aligned with the subdivision marking intermediate the first and second indicia on the second scale.

9. Apparatus according to any preceding claim, wherein synchronization of the movement of a casting truck of a foundry line with the movement of a corresponding chain truck' in a mobile casting station is controlled by the subdivision markings of the first scale which are read by the first reading means.

10. Apparatus according to any preceding claim, and further comprising second computing and control means to address a casting truck to a predetermined chain truck or trucks.

11. Apparatus for identifying moulds in a foundry line substantially as hereinbefore described with reference to the accompanying drawings.

12. A process for identifying moulds in a foundry line having a series of chain trucks travelling over a given path, each of which carries at least one mould, the length of a chain truck being equal to the pitch of the chain and at least one casting truck with a casting ladle containing molten material for filling the moulds, the or each casting truck being adapted to be moved along a casting face adjacent a corresponding portion of the path of the chain trucks and to be brought close to a chain truck to fill the moulds carried by the chain truck, the process comprising: determining from a first reading means the location of a chain truck with which is associated an indicium representing an integer and a first scale representing the length of the chain truck and having marked thereon ni subdivisions, the first reading means detecting the indicium associated with the chain truck and the subdivision marking on the first scale with which it is aligned; determining the position on the casting face of a casting truck with which is associated a second scale graduated in indicia representing integers separated by intervals proportional to the pitch of the chain, the interval being divided into n2 subdivisions, from a second reading means which reads from the second scale the indicium and subdivision marking corresponding to the position of the casting truck; and using first computing means to calculate from the two readings which particular chain truck is associated with a given casting truck.

13. A process for identifying moulds in a foundry line substantially as hereinbefore described with reference to the accompanying drawings.