SPIN-DRYER FOR BASKETS

Description

[0001] The invention relates to a spin dryer with a vertical axis of rotation for containers with a rectangular prismatic shape of various sizes, which are used, for example, as returnable containers for the transport of fruit, vegetables, and beverages, with fixed or foldable side walls in an open or closed position, and for relatively low stacked containers, wherein the stack height is equal to or slightly less than the height of the spin dryer containers with non-foldable side walls.

[0002] From EP 1191292 A1 of the same applicant, a drying centrifuge with a vertical axis of rotation for palletized crates with hinged side walls is known. This high-performance centrifuge is only suitable for large crate washing systems and requires an efficient feeding and discharge system.

[0003] From EP 1154214 A1, a drying centrifuge with a vertical axis of rotation for stacked crates of the same dimensions is known. This centrifuge is not suitable for crates of different dimensions and must be equipped with a stacking device at the inlet to the centrifuge. The stacked crates are fed laterally into a centrifuge cage that can be opened and closed laterally; this opening and closing before and after the centrifugation process significantly extends the production cycle.

[0004] From DE 4140989 A1, a spin dryer with a vertical axis of rotation for stacked crates is known. During the spinning process, the stack of crates is pressed against the rotating lower surface by a vertical hold-down device. This device also requires a stacking device arranged upstream of the spin dryer, and the stacked crates must all have the same dimensions.

[0005] From EP 3392585 B1 of the same applicant, a spin dryer with a vertical axis of rotation is known for rectangular prismatic trays with hinged side walls, wherein the side walls can be in a folded or unfolded position, or also for trays of different sizes and with fixed side walls. The spin cage of this machine is positioned above the horizontal transfer devices for the fed trays at a slightly greater distance than the maximum height of the trays that can be processed. The trays are fed in with their bottoms aligned with the conveyor belts or transfer devices; the side walls can be folded in or out, or not foldable and directed upwards towards the spin cage.The centrifugal cage is open at the bottom and has at least one row of rungs projecting downwards from the cage floor. These rungs are dimensioned according to the internal dimensions of the crates being centrifuged, ensuring that the crates, inserted into the cage by means of a lifting table, are secured in a central position. For processing crates with different dimensions, one or more rows of downward-projecting rungs may be provided, arranged concentrically to the first row, either inside or outside it. During centrifugation, the crates are held inside the cage between the lifting table, which acts vertically from below, and a pressure plate, which acts from above and is coaxial with the axis of rotation of the cage.This centrifuge has the disadvantage that, in particular, the travel of the lifting table, regardless of the height of the crate sides or their folded or unfolded position, must always be greater than the maximum height of the processable crates with fixed or unfolded side walls during the insertion and removal of the crates into the centrifuge cage. This is because the lower edge of the centrifuge cage must be further away from the crate support surface during feeding than the maximum height of the processable crates. Consequently, the loading and unloading times for the centrifuge cage are long, even for crates with folded side walls, which have a very modest height, and for those with low side walls.Furthermore, the arrangement of the centrifugal cage above the feed conveyor belts or transfer devices makes it more difficult to effectively collect and drain the water and to carry out cleaning and maintenance work on the centrifugal cage itself and on the corresponding collection and drainage devices.

[0006] From JP 2002206857A, a centrifugal dryer for pallets of various types is known in which a pallet retaining element, together with the pallet, can be detached from the rotating shaft of said retaining element and transported by means of a lifting device onto a conveyor belt for removal from the centrifugal chamber, while a retaining element together with a pallet of various shapes is fed into the centrifugal chamber. The centrifugal process takes place above the transfer level of the pallets and the corresponding retaining element, which means that the transfer devices are exposed to the water and dirt particles that are washed off the pallets during centrifugal processing.

[0007] The invention aims to create a drying centrifuge as described above, which is suitable for the efficient drying of individual containers with fixed or hinged side walls in open or closed positions, or of stacks of containers which have a modest height, in very short times, wherein the containers fed to the centrifuge can also have different dimensions and efficient drainage of the water as well as convenient access to the centrifuge cage and to its external and internal components for cleaning and maintenance work is ensured.

[0008] To solve this problem, the invention proposes a centrifugal dryer with a vertical axis of rotation of the centrifugal cage, which can be loaded from above by means of a horizontal loading / unloading platform. This platform is attached to the upper end of a shaft that projects from the bottom of the centrifugal cage and is vertically displaceable, coaxially with the axis of rotation of the centrifugal cage. This loading / unloading platform is loaded with individual containers or a stack of containers of modest height by means of a transfer device that extends in a horizontal plane parallel to the plane in which the upper edge of the loading / unloading opening of the centrifugal cage is located. Above the centrifugal cage and coaxially with it, a retaining / pressure plate is provided, which is rotatably mounted coaxially with the axis of rotation of the centrifugal cage on a first vertically movable rod.This rod can itself be mounted so that it can move vertically, or a second vertically movable rod can be mounted on this first rod, the latter having a sliding element at its lower end for a cover plate or a cover grid. During the centrifugal process, this non-rotating plate closes the loading / unloading opening of the centrifugal cage by resting, slightly spaced from the upper edge of the centrifugal cage, against fixed parts of the machine frame, the frame of the transfer devices, or the upper edge of the container that surrounds the centrifugal cage for collecting and draining the water.In the event that the rod for the closing plate is mounted on the rod for the vertical actuation of the retaining / pressure plate, part of the lowering and lifting movement for the aforementioned plates is achieved by actuating the rod which holds the retaining / pressure plate, whereby the closing plate is additionally moved vertically by the corresponding rod in order to achieve the necessary lowering movement towards the closing position for the centrifugal cage during the pressing phase, or an additional lifting movement during the lifting phase.

[0009] According to a further development of the invention, the rods for actuating the retaining / pressure plate or the closure plate can be actuated pneumatically or hydraulically by means of a cylinder with piston, or mechanically by means of a rack, toothed belt, chain, or electric actuator. The aforementioned actuating devices can be equipped with known devices for detecting the target position of the plates in order to indicate any malfunctions caused by damaged containers or improperly closed side walls. These detection devices can be, for example, a pressure sensor in the case of hydraulic or pneumatic actuation, or a linear detection probe in the case of mechanical actuation, and can be attached to one of the mechanical actuating elements or to the plate itself.The aforementioned detection of irregularities during the loading phase of the centrifuge cage causes the damaged or poorly positioned container to be ejected from the centrifuge cage and removed as rejects after the drying centrifuge.

[0010] According to a further development of the invention, the vertical actuation of the loading / unloading platform, which acts vertically inside the centrifugal cage, and its positioning, e.g. by a magnetic linear detector or a reading device for a marker attached to the actuating rod or to the platform itself, can be continuously monitored for the purpose of monitoring the movement and position of the platform inside the centrifugal cage, thereby indicating any obstructions and malfunctions in the case of defective / deformed or incorrectly positioned containers which cause malfunctions during the loading and / or unloading phase of the containers.

[0011] The arrangement of the drying centrifuge below the infeed and outfeed level of the individual containers or stacks of containers of modest height, and the insertion of the containers from above into the centrifuge cage with the bottom of the container facing upwards, makes it possible to adapt the stroke of the loading / unloading platform and the retention / pressure plate to the effective height of the individual container or stack of containers being processed, and to simplify the structure for collecting and draining the water, which is thereby easily accessible for all monitoring, cleaning, maintenance and replacement work, and the centrifuge cage, the loading / unloading platform and the surrounding structure for collecting the water, together with the drains, are all directly accessible from above, through the loading opening of the centrifuge cage and the free opening of the structure for collecting the water, which has larger dimensions than the largest diagonal of the opening of the centrifuge cage.

[0012] The invention does not preclude the possibility that certain container models with folding side walls, which are fed individually or stacked, are fed with the bottom facing downwards in order to prevent any possible opening movement (downwards) of the folded side walls during the loading phase of the centrifugal cage.

[0013] The invention will then be explained in more detail with reference to a preferred embodiment of a drying centrifuge for containers according to the invention, schematically illustrated in the accompanying drawings, including the specific feeding and discharge devices, which serve a purely explanatory, non-limiting purpose.

[0014] The Fig. 1 Figure 1 shows a sectional view according to a vertical section plane which passes through the axis of rotation of the drying cage according to the invention and through the horizontal center line of the transfer devices for the supply and removal of the containers, with a "full size" crate with folded side walls and bottom facing upwards, lying on the loading / unloading platform during the loading phase.

[0015] The Fig. 1a shows the same cross-sectional view through the in Fig. 1 The depicted spin dryer and its spin cage with the "full size" tray inside the spin cage, which is held between the loading / unloading platform and the retaining / pressure plate, with the closing plate lowered, while a container with solid side walls awaits spin drying on the feed belt.

[0016] The Fig. 2 shows the same cross-sectional view through the in Fig. 1 and Fig. 1a The depicted spin dryer and its spin cage with the spun "full size" tray on the conveyor belt in the discharge phase and the container with fixed side walls in the spin dryer.

[0017] The Fig. 2a shows the same cross-sectional view through the in Fig. 1 , 1a and 2 The depicted spin dryer and its spin cage with the container with fixed side walls inside the spin cage, held between the loading / unloading platform and the retaining / pressure plate, with the lowered closure plate, while a "full size" type crate with folded side walls is in waiting position on the feed conveyor.

[0018] The Fig. 3 shows a cross-sectional view through a centrifugal cage according to the invention, according to a vertical section plane which passes through the axis of rotation of the centrifugal cage together with the loading / unloading platform in lowered position and the raised retaining / pressure plate.

[0019] The Fig. 3a shows a sectional view according to a vertical section plane through the axis of rotation of the retention / pressure plate, the holder for said plate and through the closure plate.

[0020] The Fig. 3b The figure shows the perspective view of the retention / pressure plate, together with the closure plate of the centrifugal cage according to the invention and the corresponding vertical actuating elements, seen from below.

[0021] The Fig. 3c Figure 1 shows the perspective view of the ejection cage according to the invention, including the loading / unloading platform, in a lowered position, viewed from above.

[0022] The drying centrifuge according to the invention for single or modestly stacked containers 10, 10a of different dimensions, with fixed or foldable side walls, in an open or closed state, which according to the invention are generally fed in closed with the bottom facing upwards and in the case of certain models with the side walls folded inwards with the bottom facing downwards, consists essentially of: a frame 1 which is traversed horizontally by at least one feed conveyor belt 4x or a loading conveyor belt 4, transport belts 4a and a discharge conveyor belt 4b for the transfer of the containers 10, 10a, - a waiting station B, - a centrifuge station C with an enclosing structure for collecting the water with (not shown) closure, inspection and safety hatches.

[0023] To accelerate the centrifugation process, the containers 10, 10a are fed to the centrifugation station C individually from the outer horizontal, known, continuously running feed conveyor 4x, from a horizontal feed conveyor 4 which operates with pauses and at a higher speed than the aforementioned outer feed conveyor 4x, in order to create spacing between the removed container and the containers brought forward on the outer feed conveyor 4x, and are individually removed from the centrifugation station C, which is equipped with a pressure and sealing device 3. fig 2 supplied, wherein in the area of ​​the transfer between the two aforementioned conveyor belts a known mechanism with a vertically movable retaining element 6a from below acts to retain the series of the following containers brought forward on the outer feed conveyor belt 4x.

[0024] The first container 10, 10a, brought in by the outer feed conveyor 4x, is held in the known detection station A for the purpose of recording the dimensions, the shape of any damage, and / or the open / closed position of the side walls using a camera 5, 6a. Of course, if the centrifuge dryer is used in a plant that processes only a single container model, no photographic recording is necessary; instead, only the regular open or closed position of the side walls is recorded, e.g., using a light barrier or laser. If defects are detected, if the side walls are only partially open or closed, or if the dimensions or shapes are not suitable for the subsequent centrifugation, the container is removed in a known manner by pushing it transversely to the feed direction H, or by free fall, e.g.,in the case of conveyor belts 4a or transfer devices which grip the containers laterally and can be spaced apart from each other, ejected. In the case of a model of a container 10, 10a which is centrifugal, has no defects and whose side walls are all open or closed, this container 10, 10a is conveyed horizontally into the centrifugal station C by transferring it from the feed conveyor belt 4, by means of which the ejection of non-centrifugal or defective containers can also take place, to a conveyor belt 4a parallel to each other, acting laterally on the container 10, 10a, to a position above the open side of the centrifugal unit according to the invention. figs 2 to be occupied. This has a base 2a and upwardly projecting rungs 2b, 2c and is arranged below the support or transfer level of the containers 10, 10a, which are brought in on the feeding conveyor belt 4 and by means of transport belts 4a. By spacing the laterally acting transport belts 4a, the container 10, 10a rests on the raised loading / unloading platform 2t, in order to then be moved between the corresponding rungs 2b, 2c of the centrifugal tray. figs 2 to be lowered 2v and then held in the lowered position by the retaining / pressure plate 3a. This plate 3a, rotatably mounted 3r at the lower end of the vertical rod 3f, is driven by a motor 3m via a toothed belt 3n. Initially, it is driven 3w together with the closing plate 3b, which is mounted at the end of the rod 3c and is connected 3k to the rod 3f. In a second moment, the rod 3c, which is moved vertically 3v by a pneumatic cylinder 3d, is connected 3k to the aforementioned rod 3f and acts on the closing plate 3b to open the centrifugal chamber. figs 2 to close / open. The aforementioned 2t loading / unloading platform has one that is coaxial to the rotational axis of the centrifugal wheel. figs 2 , by means of a vertically actuated 2v pneumatic or hydraulic cylinder 2w connected to a pressure source, shaft 2u. The rungs 2b, 2c of the Kä figs 2 can be connected to each other at their extreme points, opposite the ends 2a attached to the ground, by rigid elements 2q, 2z. The slingshot fig 2 The lower side has a shaft 2y which is rotatably mounted 2r in the bearing 2s attached to the frame 1 of the machine. The shaft 2y of the centrifugal cylinder figs 2 The lower end of the platform features a pulley 2p on which the belt 2n or another transmission element driven by motor 2m acts. To determine the position of the loading / unloading platform 2t along its vertical path, a probe, e.g., for magnetic linear measurement 2e, can be provided, e.g., near the sliding area of ​​the shaft 2u. This probe is triggered by a magnet 2d attached to the lower end of the shaft. This measurement is important so that the loading / unloading platform 2t, depending on the dimensions of the container or stack of containers to be loaded, assumes the lowered position based on the height of the containers or stacks being processed, and, in the subsequent unloading phase, assumes the raised position suitable for transferring the spun container or stack of containers onto the discharge conveyor belt 4b or another known discharge device. Above and coaxial to the centrifugal force fig 2 A pressure and locking device 3 is provided, comprising a retaining / pressure plate 3a and an optional locking plate 3b. The retaining / pressure plate 3a is attached to the lower part of the vertical rod 3f by means of a support element 3g and a sliding element 3y. The rod 3f is guided vertically 3h with respect to the frame 1 and is moved 3w by a motor 3m via a belt or chain 3n. The same rod 3f has at its upper end a bracket 3k for the actuating and monitoring device of the rod 3c. This device consists of a pneumatic or hydraulic cylinder 3d, which moves the rod 3c vertically 3v, and a pneumatic or hydraulic cylinder 3e equipped with a pressure probe or a sensing device for the position of the piston of the cylinder 2d.The aforementioned retaining element 3g is fixedly connected to the closing plate 3b at one end, while the other part is connected by means of the sliding element 3y, which slides along the lower part of the rod 3f. The connection between the end of the rod 3c and the retaining element 3g is made by a transverse pin 3x. The closing plate 3b, together with the aforementioned monitoring devices, enables, for safety monitoring during the centrifugal process, the indication of minimal protrusions on the containers loaded into the centrifugal cage that extend beyond the upper edge of said centrifugal cage. The aforementioned arrangement between the rotatably mounted 3r retaining / pressure plate 3a and the vertically adjustable 3v, but non-rotatable, closing plate 3b allows the rotatably mounted 3r closing plate 3b, together with the retaining / pressure plate 3c, to move towards the centrifugal cage. fig 2 to lower 3w until this last one holds the container 10, 10a, or the stack of containers, in the direction of the loading / unloading platform 2t. Subsequently, the non-rotating closing plate 3b is lowered further 3v by actuating the cylinder until it rests on the designated stops which are attached, for example, to the vertical walls of the enclosing structure for collecting the water, to the fixed structure of the conveyor belts 4a or the transfer device for loading the centrifugal cage, or to the frame 1 of the machine in such a way as not to interfere with the centrifugal cage. fig 2 to come into contact. Be it the device for actuating the rod 3f with retaining / pressure plate 3a, as well as the actuating device for the closing plate 3b, have a probe or device for determining the target position of the contact with the bottom of the container being processed, or its contact with the support seat during the closing of the centrifugal cylinder. fig 2 In the event that one of the aforementioned survey probes indicates an abnormal position or a target position not being reached, the closing plate 3b is raised together with the retaining / pressure plate 3a 3w and the loading / unloading platform 2t is raised 2v to remove the damaged or poorly positioned container from the centrifuge. fig 2 to unload and excrete.

[0025] The movements 3w or 3v of the retaining / pressure plate 3a and the closing plate 3b can be carried out depending on the dimensions (height) of the individual or stacked containers, or the containers, during lifting by the loading / unloading platform 2t.

[0026] The invention does not preclude the loading of the containers 10, 10a, or the stack of containers, into the centrifugal tray. fig 2 by gravity, possibly by free fall, and that, during spinning, the individual or stacked containers are not held back by the retention / pressure plate 3a.

Claims

1. Spin dryer for individual containers with fixed or foldable, open or closed side walls or for a stack of containers (10,10a), the height of which is not greater than the maximum height of the individual containers to be machined, consisting of a spin dryer cage (2) inside of which a loading / unloading platform (2t) acts (2v) and a feed conveyor belt (4) which can be used as maintenance station (B) and which supplies the containers to a subsequent spin drying station (C) with the spin dryer cage (2) in order then to bring them horizontally by means of conveyor belts (4a) or transfer devices which act laterally on the containers, into a region above the spin dryer cage (2) which is housed by means of a spindle (2y) on a frame (1) inside of which a fixed extensive structure for collecting and discharging the spin drying water is housed (2s) rotatable (2r) according to a vertical axis and is driven by a motor (2m), wherein the spin dryer cage has a horizontal floor (2a) from which project rungs (2b, 2c) in the direction of the loading / unloading opening of the spin dryer cage (2), between which the containers (10,10a), during spin drying, are contained between the loading / unloading platform (2t) and a containing / pressing plate (3a) fastened to a rod (3f) which can be moved (3v) vertically, both acting (3w, 2v) vertically and coaxially to the axis of rotation of the spin dryer cage (2), characterised in that the spin dryer cage (2) is arranged beneath the plane for transferring the container (10,10a) supplied by means of conveyor belts (4a) with floor (10,10a) aligned upwards, that the loading / unloading opening of the spin dryer cage (2) is aligned upwards, that the loading / unloading platform (2t) including shaft (2u) acts (2v) vertically inside the spin dryer cage (2) and rotates (2r) together with same and that the containing / pressing plate (3a) housed rotatable (3r) acts on a rod (3f) while idling, in order to contain the individual containers (10,10a) or stack of containers, during spin drying, inside the spin dryer cage (2), abutting against the loading / unloading platform (2t).

2. Spin dryer according to claim 1, characterised in that, for reasons of safety, for the purpose of avoiding damage, a non-rotating closing plate (3b) is provided in a parallel upper position at the containing / pressing plate (3a) for the purpose of avoiding damage, which plate, for the purpose of closing the spin dryer cage (2), can be moved vertically (3v) during rotation (2r) of the spin dryer cage (2) and the containing / pressing plate (3a), and that said closing plate (3b) in lowered closure position abuts, slightly removed from the upper edge of the spin dryer cage (2), directly against parts of the frame (1) on fixed parts of the conveyor belts (4a) acting laterally on the containers or transfer devices on the upper edge of the structure surrounding the spin dryer cage (2), for capturing the water from spin drying or against corresponding stops projecting from said fixed parts.

3. Spin dryer according to claims 1 and 2, characterised in that the vertically movable (3w) rod (3f) is driven, hydraulically or pneumatically, together with the containing / pressing plate (3a) and is connected to the rod (3c) for vertical movement (3v) of the closing plate (3b) by means of a holder (3k), which closing plate (3b) is moved by a hydraulic or pneumatic cylinder (3d), mechanically or by means of an electric servo-drive for vertical movement housed on the rod (3f) or on the containing / pressing plate (3a).

4. Spin dryer according to claims 1, 2 and 3, characterised in that the hydraulic or pneumatic cylinder (3d) or the electric servo-drive for vertically moving (3v) the closing plate (3b) is held separately by the rod (3f) for actuating (3w) the containing / pressing plate (3a) to the fixed frame (1).

5. Spin dryer according to claim 1 and 2, characterised in that the vertical movement (3v) of the closing plate (3b) is monitored by a device for ascertaining the position of the closing plate (3b) relative to the upper edge of the spin dryer cage (2).

6. Spin dryer according to claim 1, characterised in that the loading / unloading platform (2t) is firmly held at the top end of a shaft (2u), which is housed slidably inside the spindle (2y) of the spin dryer cage (2), coaxially to same, that said shaft (2u) is moved (2v), vertically by means of a hydraulic or pneumatic cylinder (2w) or mechanically, by a toothed rack, a chain, a toothed belt or an electric servo-drive acting on the bottom end of the spindle (2y) from the spin dryer cage (2).

7. Spin dryer according to claim 1 and 3, characterised in that the device for moving (3w) the containing / pressing plate (3a) vertically is equipped with a probe which is suitable for overcoming a possible failure to reach the target position, which results when lowering the containing / pressing plate (3a), in the event of a damaged container (10,10a), with irregularly folded side walls or in the case of the poor positioning thereof inside the spin dryer cage (2).

8. Spin dryer according to claim 1, characterised in that the device for moving (2v) the loading / unloading platform (2t) is equipped with a probe for the purpose of ascertaining the target position which may not have been reached as a consequence of defective, deformed or poorly positioned containers inside the spin dryer cage (2).

9. Spin dryer according to claim 1, characterised in that the vertical movement (2v) of the loading / unloading platform (2t) and the positioning of same inside the spin dryer cage (2) is raised by a probe (2e) for linear magnetic ascertaining, on which a magnet (2d), fastened at the bottom end of the shaft (2u) has an effect, or by the read-in device which can read the position and change in position of a collation mark attached to the shaft (2u) of the loading / unloading platform (2t) or attached to same.

10. Spin dryer according to claim 1, characterised in that loading the individually or stacked containers (10,10a) takes place in the spin dryer cage (2) due to the force of gravity and that spin drying takes place without using a containing / pressing plate (3a), by progressively lowering (2v) the loading / unloading platform (2t) together with the individual container or stack of containers or, in a free case with the loading / unloading platform (2t), at the point of the container or stack of containers being released from the conveyor belts or transfer devices (4a) acting above the spin dryer cage (2) in already lowered position.

11. Spin dryer according to claim 1, characterised in that an ascertaining station (A) is arranged at the point of the container (10,10a) being introduced into the spin dryer for the purpose of recognising the container model, the dimensions and the folded or unfolded position of the side walls of the container (10,10) to be dried, that this is provided in the region of transfer from the supply conveyor belt (4x) to the subsequent feed conveyor belt (4), that in the same region, a containing mechanism (6) is provided at the outlet to the supply conveyor belt (4x) for the purpose of containing the container, that the subsequent conveyor belt (4) can be used as maintenance station (B), which acts possibly as a collecting sector before the subsequent spin drying station (C) and which is suitable or equipped for screening out possible containers which are defective or cannot be spin dried, that the supply conveyor belt (4x), the subsequent feed conveyor belt (4), the conveyor belts (4a) or transfer devices which act laterally on the containers and possibly the discharge conveyor belt (4b) or transfer member for transporting away the spin dried containers, lie in a common horizontal plane and the loading / unloading opening of the spin dryer cage (2) likewise lies in this plane or slightly deeper.