FR2459000A1 - Machine for demoulding pressed cooked ham from box mould - has automatic lid removal, mould inversion and ham disposal - Google Patents

Abstract

A machine for demoulding a pressed ham after cooking under pressure in a box mould with a removable pressure cover. The mould is clamped in a cradle which can be rotated through 180 degrees about a horizontal axis in order to invert the mould. Before inversion of the mould its cover is removed by a take-off mechanism. Underneath the cradle, a reception conveyor is located to receive the prod. discharged from the inverted mould. Cradle inversion is pref. effected by fluid power cylinder(s) the mould pref. has a hole through its base and the cradle is fitted with a compressed air supply nozzle which is brought into engagement with the base hole to assist in demoulding the prod. The original underside of the cradle is fitted with a conveyor. This conveyor comes into action after inversion of the cradle, being used to carry off the removed mould cover for washing.

Description

 The present invention relates generally to a demoulding machine and relates more particularly to the case of hams.

 As is known, to present good mechanical strength capable of allowing it to be cut correctly into slices, a delicatessen ham, of the type commonly sold under the name of Parisian hams, is usually, when cooked, enclosed in a mold, and is compressed therein by a cover removably attached to such a mold.

 This mold can have any configuration, which is most often a generally parallelepiped or ovoid configuration, adapted to the configuration sought for the ham to be molded, and / or have any dimensions, the lid which closes it being attached to a terminal face. larger section or smaller section of such a mold.

But, in all cases, the cover called upon to close this mold is usually provided, laterally, at the ends of a crosspiece movably mounted on two balusters against return springs, two closing arms, forming racks, by which it is adapted to engage with the edge of such a mold.

 After cooking, a ham must be extracted from the mold in which it is found.

 This extraction involves on the one hand the opening of the mold, by removing the lid which closes it, then the inversion of this mold, for demolding the ham it contains.

 These two operations are usually performed to date manually, the demoulding of the ham being however facilitated by the use of a blowing nozzle applied for this purpose to the hole which commonly comprises for this purpose the bottom of the mold used, the jet compressed air blown into this mold by this blowing nozzle quickly leading to an expulsion of the ham previously contained in this mold.

It has certainly already been proposed so-called demoulding machines around which the various operations mentioned above are organized, as well as those leading to an evacuation of a part of the demoulded ham, intended for a packaging station and / or shipping, and on the other hand the mold and its cover, to a washing station.

 However, in machines of this type known to date, the operations of removing the cover and inverting the mold remain manual, only in practice being mechanized, those consisting in applying a blowing nozzle to the hole in the bottom of the mold.

The present invention generally relates to a demoulding machine within which, on the contrary, all the operations necessary for the required demolding are mechanized.

More specifically, it relates to a demoulding machine, in particular for hams, generally characterized in that it comprises, in combination, a cradle, which is suitable for receiving a mold to be opened and emptied, and which is rotatably mounted between at least two positions, namely a first normal standby position, and a second re-molded release position, for example at 1800 with respect to the previous one, and, on either side of said cradle, on the one hand, on a first side thereof, an extractor, which is capable of removing its cover from such a mold, and which is for this purpose mounted movable between two positions, namely a first position separated from waiting and a second close sampling position, and, on the other hand, on the other side of said cradle, a receiver, which is adapted to receive the demolded product and, possibly, to evacuate it, in this case a ham.
Thus, during the working cycle of the machine according to the invention, there are automatically, and successively, ensured, first the opening of the mold, by removing its cover, then the inversion of this mold.

 Of course, to facilitate the extraction of this mold from the ham it contains, provision is made for the use of a blowing nozzle.

 However, according to the invention, it is not directly applied to the bottom of the mold concerned.

 Indeed, the machine according to the invention is advantageously adapted to the treatment of molds of dimensions, and in particular of different heights, and, for this purpose, its cradle is formed on the one hand of a chassis, which is rotatably mounted. , and on the other hand an adapter block, which is suitable for receiving a mold to be opened and emptied, and which for this purpose comprises, at an advantageously constant distance from the extractor in its normal waiting position , for regular work of this extractor without modification of the latter according to the dimensions of the mold to be treated, a sole suitable for receiving such a mold and adapted thereto.

 Therefore, according to the invention, the blowing nozzle, which is movable, is disposed on the chassis of the cradle, at a distance from the sole which comprises the adaptation block carried by it, and this adaptation block is equipped with 'a tubular extension, which extends generally between said blowing nozzle and said sole, and which is mounted axially movable.

It is therefore by means of this extension, which is of length adapted to the height of the molds to be treated, that the blowing of compressed air takes place in such a mold.

For the same purpose of adapting the machine to different mold heights, the receiver that this machine comprises is according to the invention formed by a plate mounted vertically movable between a low waiting position and a high receiving position.

Thus, whatever the mold treated, the height from which falls on such a receiver the ham extracted from this mold remains substantially constant, and is made sufficient so that it does not result in untimely deterioration of such ham.

 Preferably, the extractor, the cradle and the receiver of the machine according to the invention are staggered vertically on the same frame, the axis of rotation of said cradle being horizontal.

 As a result, this machine easily lends itself to the joint implementation of conveyors allowing, at a first level, the supply of the machine with molds to be opened and emptied, on a first side of the machine, and the evacuation molds emptied, on the other side of this machine, and, at a second level, lower than the previous one, the evacuation of the hams extracted.

In addition, at a third level, higher than the previous one, can advantageously, if desired, be implemented a conveyor suitable for the evacuation of the covers of the treated molds, the cradle of the machine according to the invention comprising for this purpose its back a conveyor, on which the extractor comes to deposit, during the overturning of a mold, the cover previously removed from it, and which is able to direct this cover towards the preceding evacuation conveyor.

The machine according to the invention is therefore advantageously capable of ensuring complete automation of the various operations to be carried out during the demolding of any products, and in particular hams.

The characteristics and advantages of the invention will become apparent from the description which follows, by way of example, with reference to the appended schematic drawings in which
Figure 1 is a perspective view of a mold capable of being treated by the demolding machine according to the invention
Figure 2 is an overall perspective view of this machine;
ballast Figures 3 and 4 are, on a different scale, partial sectional views along lines III-III and IV-IV of Figure 2
Figure 5 shows on a larger scale, and with cutaway, the detail of Figure 3 identified by an insert V on it
Figure 6 is a partial perspective view of the machine according to the invention illustrating a first phase of operation thereof
Figure 7 is another partial perspective view of the machine according to the invention illustrating another phase of operation -of it
FIG. 8 is a schematic block diagram of the machine according to the invention illustrating the various control means which it comprises.

 As shown in FIG. 1, the mold 10 to be opened and emptied arrives at the machine according to the invention closed by a cover 11, which is engaged in the opening of this mold, and which carries two protruding columns 12, on which is mounted sliding, against springs 13, a cross member 14.

 At the ends of this cross-member 14 are articulated two closing arms 15, forming racks, by which the cover is engaged with a flange 16 bordering peripherally, towards the outside, the opening of the mold 10.

 In addition, as visible in FIG. 5, the bottom of such a mold 10 is pierced with a hole 17.

 In this mold 10, the ham 11 from which the extraction is to be compressed is compressed by the cover 11.

 To do this, the machine according to the invention generally spreads, in combination, Figures 2 and 8, a cradle 18, which is adapted to receive a mold 10 to open and empty, and which is rotatably mounted between at least two positions, namely a first normal waiting position, represented in FIG. 2 and in FIG. 8, and a second inverted demolding position, represented in FIG. 7, at 1800 with respect to the previous one, and, on both sides said cradle, on the one hand, on a first side thereof, 'an extractor 19, which is capable of removing from such a mold 10 its cover 11, and which is for this purpose mounted movable between two positions, namely a first position apart from waiting, - shown in Figure 2 and Figure 8, and a second close position of removal, shown in Figure 6, and, on the other hand, on the other side of said cradle , a receiver 20, which is suitable for receiving the demolded ham, and in practice, as will appear below, for discharging it .

In the embodiment shown, the extractor 19, the cradle 18 and the receiver 20 are staggered vertically, in the order indicated, on the same frame 22, and the axis of rotation of the cradle 18, materialized by a shaft 23 rotatably mounted in bearings 24 carried by the frame 22, is horizontal.

the frame 22 will not be described here in detail: it is a network of uprights connected by crosspieces, and the general reference 22 which designates it is here indifferently applied to one or the other of these constituents.

 In practice, the normal waiting position and the inverted demolding position of the cradle 18, as explained above, are the only ones that this cradle can occupy, said cradle being controlled in reciprocating movement between these two positions using two parallel cylinders 25A, 25B, whose piston rods 26A, 263 are coupled to the ends of the same chain 27 passed in a U shape on a pinion 28 wedged on the shaft 23 of this cradle.

 The power supply to the cylinders 25A, 25B is controlled by limit switch contacts 29A, 29B which, as shown diagrammatically by the block diagram in FIG. 8, are themselves controlled by a cam 30 wedged on the shaft 23 .

In practice, in the embodiment shown, the cradle 18 is formed by a U-shaped chassis 32, which is rotatably mounted, the shaft 23 forming pins projecting from the lateral wings 33.33 ′ of this chassis, and an adapter block 34, which is adapted to receive a mold 10 to open and empty, said adapter block being attached removably to said frame and lockable in position thereon.

the U-shaped chassis 32 will not be described in full detail here; its realization indeed falls within the domain of those skilled in the art, and it will suffice to specify that, as shown, it may for example consist of a network of stringers and sleepers, its lateral wings 33.33 ' being however each coated on a full surface with a closure plate 35.35 '.

 In the embodiment shown, the adapter block 34 forms a slide-out drawer on the frame 32, parallel to the lateral wings 33, 33 'thereof, this adapter block comprising a frame p by which it is engaged in slides 38,38 'carried projecting by said lateral wings 33,33', on the internal face of the latter.

 At one of its ends, FIG. 2, this frame 37 carries cantilever brackets 39.39 ′ by which the adaptation block 37 can be locked in position on the lateral wings 33, 33 ′ of the chassis 32, these having for this purpose ears on which are articulated keys, with knurled screwing button, capable of coming into engagement with said brackets 39, 39 '.

 The production of the frame 37 of the adapter block 34 will not be described here in all its details either, this frame 37 being in practice formed, as shown, by a network of stringers and sleepers.

In its median zone, it comprises, parallel to the lateral wings 33.33 'of the chassis 32, two sills 40.40'. jointly forming a sole 41 suitable for receiving a mold 10 to be opened and emptied, as shown diagrammatically in broken lines in FIGS. 3 and 4.

 This sole 41 is disposed between two series 42A, 42B of rollers 43 which extend generally perpendicular to the lateral wings 33, 33 ′ of the chassis 32, on the frame 37 of the adaptation block 34, and the top zone of which is one level slightly higher than that of said sole 41.

 As illustrated in FIG. 5, on the middle part of the frame 32, in the middle part of the latter, a blowing nozzle 45 is movably mounted under the control of a jack 46 whose body is fixed to said frame.

This blowing nozzle 45, which by a line 47 is capable of being connected to any source of compressed air, is thus, according to the invention, established at a distance from the sole 41 intended to receive the mold 10 to be opened and empty, and the adapter block 34 comprising this sole 41 is equipped with a tubular extension 48, which extends generally between the blowing nozzle 45, and the sole 41, and which is mounted axially movable.

In the embodiment shown, this extension 48 is housed in a chimney 50, with a U-shaped section, secured in overhang to the beams 40, 40 'constituting the sole 41.

In FIGS. 3, 4, 7, and for simplification of celLesci, only this chimney 50 is represented.

 In practice, as shown in FIG. 5, the tubular extension 48 is slidably engaged in guide spacers 51 which the chimney 50 has for this purpose, and it is subjected to a return spring 52, which, bearing on such a spacer 51 urges it permanently in the direction of a normal waiting position for which it is supported on a stop constituted by the other of the spacers 51, the direction in question being that opposite to the sole 41.

Anyway, at each of its ends, the tubular extension 48 is equipped with a suction cup 54.

Furthermore, wedging means are provided on the cradle 18 to enclose the mold 10 to be opened and emptied.

In the embodiment shown, these wedging means are carried by the adapter block 34 that comprises the cradle 18, and are formed on the one hand, on the first side of this cradle, on a support stop. 56 and, on the other hand, on the other side of said cradle, a movable pusher 57, capable of being actuated, by means of a transmission linkage 58, by a jack 59 carried by the chassis 32 from cradle 18.

 Finally, in the embodiment shown, the cradle 18 carries on its back, that is to say on the outer face of the middle part of its chassis 32, an autonomous conveyor 60.

 In the embodiment shown, this is a chain conveyor which extends substantially perpendicular to the lateral wings 33, 33 ′ of the chassis 32 and which is capable of being controlled in rotation by a motor 61, Figures 4, 7 and 8.

 The extractor 19 comprises, for its part, a support 63, which is movably mounted, and on which are articulated two controlled claws 64,64 ', suitable for gripping the cover 17 of a mold 10 to be opened and emptied.

In the embodiment shown, the support 63 forms a flange, two lateral edges of which are fitted with sockets 65.65 ′ by which it is slidably engaged on balusters 66.66 ′ secured to the frame 22, at the top of that -ci, and it is coupled to the piston rod 67 of a vertical cylinder 68.

 At its base, the support 63 carries a barrel 62 provided with a slot 78.

 In practice, claws 64,64 ′ of the extractor 19 each have a square shape, for engagement under the cross member 14 of a cover 11, and they are each coupled to the piston rod of a jack 69,69 'whose body is also articulated to the support 63 that this extractor 19 includes.

 As illustrated in the block diagram of FIG. 8, this support 63 is associated with a limit switch contact 70, and with the claws 64, 64 ′ it is likewise associated with limit switch contacts 71, 71 '.

 Furthermore, the extractor 19 is associated with two spacers 72A, 72B, which are mounted movable between a remote waiting position and an advanced service position, and which are capable of acting transversely on the lateral arms 15 of a cover. 11, for their advanced service layout.

In practice, these are rods with bevelled ends which, like a fork, jointly form a coupling 73 carried by the cradle 18, and more precisely the chassis 32 thereof.

 This coupling is movable horizontally, substantially perpendicular to the lateral wings 33, 33 ′ of the chassis 32, and it is subjected to a return spring 74 which biases it permanently in the direction of its withdrawn waiting position.

 For its passage into the advanced service position, it is associated with a jack 75, carried by the frame 22, FIGS. 3 and 8.

In addition, it is also associated with it, as shown diagrammatically by the block diagram of FIG. 8, two limit switch contacts 76,77, one for its advanced service position, the other for its remote position d 'waiting.

the receiver 20, meanwhile, comprises a plate 79 mounted vertically movable, under the control of a jack 80, between a low waiting position, FIG. 2, and a high receiving position, FIG. 7.

 In the embodiment shown, this plate 79 is formed of a support 81, to which is coupled a guide rod 82 slidingly passing through a plate 83 secured to the frame 22, and a flap 84 articulated on the support 81.

 With this flap 84, which is formed by a network of rollers 85 forming a conveyor, there is associated a fixed stop 86, which, carried by the frame 22, is interposed on the path swept by the plate 79 between its high receiving position and its low waiting position, and on which the flap 84 of this plate 79 bears, so that, for the low waiting arrangement, said flap is inclined, as illustrated in FIG. 2.

the flap 84 is then generally in continuity with an evacuation conveyor 87 secured to the frame 22.

 In practice, and as shown, one of the rollers 85 of the shutter 84 is movable between a high position, for which it normally exceeds others, and a low position for which it acts on a switch contact 88, and the plate 79 is slaved to this switch contact 88 for its passage from its high reception position to its low standby position, the supply of its jack 80 being controlled by this switch contact 88.

 Likewise, a switch contact 90 is associated with the conveyor 87, as shown diagrammatically by the block diagram of FIG. 8, to control the movement of a ham to be evacuated thereon.

the various actuators used are preferably double-acting.

 However, the cylinder 46 controlling the blowing nozzle 45 can be single acting.

 This being stated, the operating cycle of the machine according to the invention is as follows.

At the start, the extractor 19 is in the standby position, its claws 64, 64 'being themselves in the standby position, the cradle 18 is in the normal standby position for which the sole 41 which it carries for reception of a mold 10 to be opened and emptied is turned towards said extractor 19, and the receiver 20 is in the low standby position.

Pushed on the rollers 43 which frame the sole 41 of the cradle 18, a mold 10 to be opened and emptied is put in place on this sole 41, and is wedged there by said rollers, this sole 41 being at a level lower than that of said rollers.

Of course, the establishment of such a mold on the sole 41 can be ensured automatically, using for example pushers not shown, from a feed conveyor.

Anyway, a mold 10 to open and empty being in place, the machine according to the invention is started.

Be jack 59 is the first to intervene, then, with a slight delay, of the order for example of a second at most, the jacks 68, 75 and 46.

By the linkage 58, the jack 59 pushes the pusher 57, and the mold 10 to be opened and emptied is thus firmly clamped between, on the one hand this pusher 57, and on the other hand the fixed stop 56 with which it is associated .

 Be jack 75 acts on the coupling 73, so that the spacers 72A, 72B pass from their retracted waiting position to their advanced service position for which, coming into contact by their bevelled ends with the articulated arms 15 of the cover 11 of the mold 10, FIG. 6, they force these articulated arms 15 to pivot outwards, and thus to escape from the edge 16 of said mold 10.

The cover 11 is therefore free vis-à-vis the mold 10.

 At the same time, the jack 46 came to apply the blowing nozzle 45 to the suction cup 54 of the tubular extension 48, then, its movement being continued, it came to apply the suction cup 54 of this tubular extension 48 to the bottom of the mold 10, around of the opening 17 that this bottom has.

 When the coupling 73 of the spacers 72A, 72B reaches the advanced service position, the extractor 19 has reached its close sampling position for which it is engaged by its slot 78 on the cross member 14 of the cover 11.

 On reaching its advanced service position, the coupling 73 of the spacers 72A, 72B acts on the limit switch contact 76, and the latter simultaneously controls the actuation of the actuators 69,69 '.

the claws 64, 64 'of the extractor 19 then engage under the cross member 14 of the cover 11, FIG. 6.

 At the end of such engagement, these claws 64, 64 'act on the limit switch contacts 71, 71', which controls the return to the initial position of the jack 68, and therefore the return to the standby position extractor 19.

 Nais, with him, this extractor 19 drives the cover 11, through the crosspiece 14 thereof.

when the extractor 19 has thus returned to the retracted standby position, it acts on the limit switch contact 70, which simultaneously controls, on the one hand, the return to the initial position of the jack 75 and therefore the return to the retracted position waiting for the coupling 73 of the spacers 72A, 72B, and on the other hand the actuation of the jack 80.

As a result of this entry into action, the plate 79 of the receiver 20 passes to the high reception position, for which its articulated flap 84 is folded down on the corresponding support 81, FIG. 7.

When the hitch 73 of the spacers 72,72B reaches its retracted waiting position, under the bias of the spring 74, it acts on the limit switch contact 77, and the latter controls the actuation of the actuator 25A , which results, by rotation of the shaft 23, the passage of the cradle 18 from its normal standby position to its inverted release position, FIG. 7.

 When the cradle 18 reaches this inverted demolding position, the cam 30 acts on the limit switch contact 29A which simultaneously controls, on the one hand the return to the initial position of the jacks 69, 69 ′, then, with a slight delay , of the order for example of a maximum of one second, the supply of the motor 61, and secondly the supply of compressed air to the blowing nozzle 45.

Due to the return to the initial position of the jacks 69,69 ′, the claws 64,64 ′ of the extractor 19 abandon the cross member 14 of the cover 11, and the latter falls in free fall onto the conveyor 60 disposed at the back of the cradle 18.

 Due to the supply of the motor 61, this conveyor 60 directs the cover which it has just received on another evacuation conveyor, not shown, in the direction for example of a washing station.

Simultaneously, due to the supply of compressed air to the blowing nozzle 45, the ham previously contained in the mold 10 is expelled therefrom, and falls in free fall, but from a low height, onto the tray 79 of receiver 20.

 On the evacuation conveyor of the cover 11, a switch contact, actuated by the passage thereof, controls the stopping of the motor 61.

At the same time, when the ham extracted from the mold 10 reaches the plate 79 of the receiver 20, it forces the raised roller 85 therefrom to act on the switch contact 88, and the latter controls the return to the initial position of the jack 80 , and therefore the return to the low standby position of this plate 79.

During this return, the plate 79 of the receiver 20 carries with it the previously demolded ham, and, its articulated flap 84 coming to bear on the fixed stop 86 provided for this purpose, it is, at the end of the race, raised in inclined position, which leads the previously demoulded ham to slide from this articulated flap 84 towards the evacuation conveyor 86, and from there towards any unrepresented recovery station.

 In reality, the switch contact 88 may only command the purge of the jack 80, a switch contact disposed on the fixed stop 86 controlling, when it makes contact with the latter of the articulated flap 84 of the plate 79, on the one hand the effective return to the initial position of the actuator 80, and on the other hand the cut off of the compressed air supply to the blowing nozzle 45 and the return to the initial position of the actuator 46 controlling this nozzle.

Under the impulse of the spring 52, the tubular extension 48 associated with the blowing nozzle 45 itself returns to the initial standby position, for which it is away from the mold 10.

When the previously evacuated ham passes, the in switch contact 90 of the evacuation conveyor 86 controls, if the cover previously deposited on the conveyor 60 has been correctly evacuated therefrom, under the control of the switch contact disposed on the corresponding conveyor , the entry into action of the cylinder 25B.

 By rotation of the shaft 23, the cradle 18 returns to the normal standby position, and at the end of this rotation, the cam 30 acts on the limit switch contact 29B.

This controls the return to the initial position of the jack 59, and therefore the release of the pusher 57.

the mold 10 previously opened and emptied is thus released, and can be evacuated, either manually, or using for example a thrust cylinder acting directly or by means of one or more new molds to be opened and empty, an evacuation conveyor not shown being provided to direct the mold 10 previously opened and emptied to any washing station for example.

 The machine is therefore ready for a new working cycle.

Of course, the present invention is not limited to the embodiment described and shown, but encompasses any variant.

 In particular, the extractor 19 may be associated with an erasable retaining wedge, suitable for coming to bear on the rim 16 of the mold 10 to be opened and emptied, without biting onto the opening thereof, and therefore thus suitable for retain this mold 10 when removing its cover 11 therefrom by said extractor 19.

 For example, such a retaining wedge can be mounted movable transversely relative to the displacement of the extractor 19, and be subjected in displacement to the coupling 73 of the spacers 72A, 72B, either that it is directly carried by one or the other of these spacers, either that it is actuated by a pusher on which comes to act, against a return spring, such a spacer.

Furthermore, instead of being controlled by reciprocating rotary movement, the cradle 18 could be controlled by continuous rotary movement.

 Similarly, if it is advisable for the mold to be removed from the mold while this mold is inverted downwards, it could be done as well, because of the compressed air ensuring this release, while the mold is lying horizontally.

 In this case, the two positions that the rotary cradle can take are only 900 from one another, and the receiver is no longer staggered vertically with the extractor.

 Likewise, the step-by-step control, by limit switch contacts, of the machine, which is advantageously a guarantee of good operational safety for the latter, is not however imperative, a centralized control, to cams for example, which can be considered.

In all cases, the adaptation block used is chosen as a function of the characteristics specific to the mold to be treated, and is changed as a function of such a mold without the rest of the machine needing to be modified.

 Furthermore, it goes without saying that the application of the invention is not limited to the demolding of hams, but that it can extend to that of the demolding of any other product.

Claims (18)

XEVEfDI CAI ONS  1. Demoulding machine, in particular hams, characterized in that it comprises, in combination, a cradle, which is suitable for receiving a mold to be opened and emptied, and which is rotatably mounted between at least two positions, namely a first normal standby position and a second inverted position for demolding and, on either side of said cradle, on the one hand, on a first side thereof, an extractor, which is suitable for taking from such a mold has its cover, and which for this purpose is mounted movable between two positions, namely a first position apart from waiting and a second position close to sampling, and, on the other hand, on the other side of said cradle a receiver, which is suitable for receiving the demolded product and, possibly, for discharging it.  2. Demoulding machine according to claim 1, characterized in that the extractor, the cradle and the receiver are staggered vertically on the same frame, and the axis of rotation of said cradle is horizontal. 3. Demoulding machine according to any one of claims 1, 2, characterized in that the cradle is controlled in reciprocating movement between its two positions, for example using one or more cylinders. 4. demoulding machine according to any one of claims 1 to 3, characterized in that, for receiving a mold to be opened and emptied, the cradle comprises a sole disposed between two series of rollers, the top zones of which are at a level slightly higher than that of said sole.  5. demoulding machine according to any one of claims 1 to 4, characterized in that the cradle comprises wedging means suitable for enclosing a mold to be opened and emptied, said wedging means comprising for example, on a first side of the cradle, a support stop, and on the other side of said cradle, a movable pusher. -6. Demoulding machine according to any one of Claims 1 to 5, characterized in that the cradle is formed by a frame, which is rotatably mounted, and by an adapter block, which is suitable for receiving a mold to be opened. and emptying, said adapter block being removably attached to said frame and lockable in position thereon. 7. demoulding machine according to claims 4 to, taken together, characterized in that the chassis of the cradle is U-shaped, its adapter block forms a drawer carried sliding on said chassis, parallel to the wings thereof, the sole provided for receiving a mold to be opened and emptied is carried by said adapter block, it is the same for the wedging means provided to grip such a mold, and the rollers associated with said sole extend perpendicularly vis- opposite the wings of said chassis.  8. demoulding machine according to any one of claims 6, 7, wherein, the bottom of the mold to be opened and emptied being pierced with a hole, a movable blowing nozzle is provided for blowing compressed air into said mold through said hole, characterized in that said blowing nozzle is disposed on the chassis of the cradle, at a distance from the sole which the latter comprises for receiving a mold to be opened and emptied, and in that the block of adaptation worn by said chassis is equipped with a tubular extension, which extends generally between said blowing nozzle and said sole, and which is mounted axially movable.  9. demoulding machine according to any one of claims 1 to 8, characterized in that the cradle carries on its back an autonomous conveyor.  10. Demoulding machine according to any one of claims 1 to 9, characterized in that the extractor comprises a support which is movably mounted, and on which are articulated two controlled claws, suitable for gripping a cover.  11. Demoulding machine according to any one of claims 1 to 10, characterized in that, being to open and empty a mold for which articulated arms ensure the closing of the cover, it is associated with the extractor, for each of said articulated arms, a spacer, which is mounted to move between a retracted waiting position and an advanced service position, and which is capable of acting transversely on such an arm for said advanced service position.  12. Demoulding machine according to claim 11, characterized in that said spacer is carried by the cradle, and there is associated therewith elastic return means, which the ground 'cite continuously in the direction of its retracted waiting position.  13. Demoulding machine according to claims 6 and 2 taken together, characterized in that the spacer is carried by the chassis of the cradle.  14. Demoulding machine according to any one of claims 10 to 13, characterized in that with the extractor there is associated an erasable retaining wedge, suitable for retaining the mold during removal of its cover by said extractor.  15. Demoulding machine according to claims 11 and 14 taken together, characterized in that said retaining wedge is mounted movable transversely to the displacement of the extractor and is subjected in displacement to the spacer.  16. Demoulding machine according to any one of claims 1 to 15, characterized in that the receiver comprises a plate mounted vertically movable between a low waiting position and a high receiving position. 17. Demoulding machine according to claim 16, characterized in that said plate is formed by a support and a flap articulated on said support, and there is associated with it a stop on which bears said flap for its low position d waiting, so that, for said low waiting position, said flap is inclined. 18. Demoulding machine according to claim 17, characterized in that the articulated flap of the receiver plate carries rollers, one of which is movable between a high position, for which it protrudes from the others, and a low position, for which it acts on a switch contact, and said plate is slaved to said switch contact for the passage from its high receiving position to its low waiting position.