OVERHEAD CONVEYOR SYSTEM

Abstract

TITLE: OVERHEAD CONVEYOR SYSTEM The invention relates to a system for conveying transport devices (7) capable of carrying articles intended to undergo treatment in a specific treatment zone (5), the conveyor system comprising an overhead conveyor (6) having a running track (64) on which trolleys (8) each carrying a suspended transport device (7) move at a first speed, in which a suspended transport device (7) has a lower end provided with securing means (71) and in which the system further comprises a secondary displacement device (12, 13, 14) arranged in said treatment zone and having drive means (132) in the lower part configured to cooperate with said securing means (71) to control the displacement of said transport device (7) in said treatment zone (5) at a second speed lower than the first speed.Figure for abstract: Figure 5.

Description

Title of the invention: OVERHEAD CONVEYOR SYSTEM Technical field of the invention

[0001] The present invention relates to the field of aerial conveyance of loads. More particularly, it relates to a conveyance system of multi-shelf transport devices capable of transporting articles to be treated in a treatment area. State of the art

[0002] In this field, usually the conveying of the transport devices carrying the articles to be treated is done using floor conveyors which causes problems among others of wear of the on-board electronic and electromechanical components which are exposed to radiation during repeated passages in the treatment zone. The solution found for this problem is to use an overhead conveying system in which the article transport devices are suspended and moved along a circuit passing through the treatment zone. Such a system has the advantage that only mechanical trolleys to which the transport devices are suspended pass through the treatment zone. The absence of a floor conveyor also provides a gain in irradiation performance, by leaving space for the product to be treated in front of the treatment beam.

[0003] However, known overhead conveying systems are not suitable for installations in which the products require specific treatment. Indeed, in such a treatment area, it is necessary for all the articles to undergo homogeneous treatment at sufficient doses. The process therefore requires low speeds and high stability, which is not compatible with the rate generally imposed by the treatment installation.

[0004] The invention therefore aims to propose a solution making it possible to maintain a normal rate in the treatment installation while controlling the conditions of movement of the transport devices in the treatment zone and thus ensuring good treatment of the products. Summary of the invention

[0005] To this end, the invention relates to a conveying system of a set of multi-stage transport devices capable of carrying articles intended to undergo treatment in a specific treatment zone, the conveying system comprising an overhead conveyor having:

[0006] - a rolling track on which trolleys move, each carrying a suspended transport device, and

[0007] - traction means capable of moving a trolley to the entrance of the zone of treatment and from the exit of said treatment zone at a first speed,

[0008] According to the invention, the suspended transport device has a lower end provided with securing means and the system further comprises a secondary movement device arranged in said treatment zone and having drive means in the lower part configured to cooperate with said securing means to control the movement of said transport device in said treatment zone at a second speed lower than the first speed.

[0009] The use of the secondary movement device as well as the means of securing the transport devices therefore makes it possible to have good control of the movement in the treatment zone and consequently ensure stability of the transport devices at the transport speed set in this zone. The precise movement of the products without swinging at an adapted speed guarantees them homogeneous treatment.

[0010] The displacement step is for example chosen so that the displacement devices are stuck to each other in the treatment zone and thus form a sort of train and avoid any loss of energy which can occur if the devices are spaced apart.

[0011] The second speed can for example be determined according to the articles to be processed, transported by the transport devices.

[0012] The second speed may further be linked to the desired treatment dose for the products, this may be the case in particular in the treatment of products by radiation, the speed of movement may be decisive for the dose of radiation received, for example to sterilize the products. For example, if the first speed is 10 to 20 m / minute, the second speed may vary between a few dm / minute and a few m / minute.

[0013] The radiation is for example ionizing radiation, for example with X-rays, gamma rays or an electron beam. However, other specific treatments are possible, for example a projection of paint or a sterilizing or washing substance.

[0014] The secondary device may comprise a lower chain carrying the drive means such as cleats.

[0015] Advantageously, the secondary device may further comprise an upper chain comprising attachment means configured to be secured with guide means arranged in the upper part of the loading devices, said upper chain being synchronized with the lower chain.

[0016] Having an upper chain synchronized with the lower chain allows for greater control over the position of the transport devices, ensuring good stability by preventing swinging along the axis of advance of the transport devices.

[0017] Synchronization between the upper chain and the lower chain can be performed by a synchronization shaft or any other synchronization means, such as an additional chain. However, the synchronization shaft has the advantage of being a simple synchronization means and reinforcing the stability of both the upper and lower chains.

[0018] Advantageously, the movement of the lower chain is managed by a motor remote from the treatment area. The fact that the motor is remote allows it to be protected from radiation by moving it away from the treatment area, which prolongs its service life.

[0019] Advantageously, the system may further comprise a lower guide rail arranged to receive a centering element arranged in the lower part of the transport devices. This makes it possible to ensure centering and stability of the transfer devices in the direction transverse to the movement.

[0020] Advantageously, the system may further comprise a transfer device arranged at the entrance to the treatment zone and configured to move a transport device from a waiting position upstream of the treatment zone to bring it into contact with the secondary device.

[0021] This facilitates the contacting of the transport devices remaining in the waiting position in which they are no longer driven by the conveyor chain to be brought into contact with the secondary drive and stabilization device and therefore ensure its drive by the latter. The contacting in this case is done more precisely than in the case where the contacting is done directly by the conveyor. In addition, such contacting can be programmed so as to respect the moment when a place becomes available in the treatment zone. By putting the loading device in a waiting position, it is possible to release the drive chain and not block traffic.

[0022] The invention further relates to an article processing installation comprising a conveying system as described above.

[0023] Advantageously, the installation comprises in the treatment zone means for treatment by ionizing radiation. Such radiation is for example X or Gamma radiation or an electron beam.

[0024] The invention also relates to a method for treating articles using an installation as described above. Brief description of the figures

[0025] Other features and advantages of the invention will appear in the description below in relation to the appended drawings, given as non-limiting examples, in which:

[0026] [Fig-1] [Fig.l] represents a partial view of an installation comprising a aerial conveyance system according to the invention;

[0027] [Fig.2] [Fig.2] is a view of a portion of the conveyor system showing a conveyor and an overhead transport device;

[0028] [Fig.3] [Fig.3] is a zoom on an area of attachment of a transport device to a conveyor trolley;

[0029] [Fig.4] [Fig.4] is a partial view of a conveyor chain;

[0030] [Fig.5] [Fig.5] is a view of a set of transport devices in the area of treatment.

[0031] In the remainder of the description, elements having an identical structure or similar functions will be designated by the same references. Detailed description

[0032] [Fig.l] represents a schematic top view of a product processing installation 1 comprising a non-sensitive part I very partially represented on the right of the figure and a sensitive part II on the left.

[0033] In part I, the installation comprises generally known storage and handling means, such means are not the subject of the invention and are therefore not detailed in this description.

[0034] In part II, the installation comprises protective walls 2 enclosing an emission zone comprising means 3 for generating radiation used for the treatment of products. The radiation generation means 3 may be means for generating any type of radiation usable in the treatment of products, for example sterilizing radiation. Such radiation may be, for example, ionizing radiation by X-rays, Gamma rays or an electron beam.

[0035] In other embodiments not shown, the treatment may be different, such as a surface treatment, paint spraying or any other reactive or aesthetic agent.

[0036] The beam 4 produced by the means 3 arrives at a treatment zone 5, the products which are in this zone at the time of impact receive a dose of the beam.

[0037] To circulate the products to be treated with the beam 4, the installation comprises an overhead conveying system 6 forming a circuit which goes from part I to part II. The products are loaded upstream of the inlet 60 and carried by the conveyor 6 towards part II to pass through the treatment zone 5 to receive one or more doses of the beam, for example by rotating in the internal loop 61. At the end of processing, the products exit through exit 62 to go to other stations in the installation in part I, for example to be unloaded and stored.

[0038] The protective walls are known per se and may comprise external walls 2 and an internal wall 21 to stop the beam if it hits between two products or between two transport devices 7. It is not necessary here to give more details of such walls which are known per se for such applications.

[0039] To move the products to be processed, the conveyor system comprises loading devices 7, an example of which is shown in [Fig.2] and [Fig.5], such devices may comprise several stages in which the articles to be processed are loaded.

[0040] The conveyor 6, in the example of FIG. 2, comprises a lower part comprising a rolling track 64 on which carriages 8 move, each carrying a suspended transport device 7.

[0041] As shown in [Fig.3], a carriage 8 comprises wheels 81 for rolling on the rolling track 64 and a conveyor device 83 to which the conveyor device 7 is suspended. The carriage 8 further comprises a hooking means 82 which can move from an upper hooking position, allowing the carriage 8 to be driven with the conveyor device 7, to a lower position for stopping the carriage 8 and the conveyor device 7.

[0042] In the illustrated example, the conveyor is a dual-rail conveyor, the upper rail 63 of which, as shown in [Fig.4], comprises rolling means 91 of a traction chain 9. The traction chain rotates continuously and comprises drive devices 92. When a drive device 92 encounters the hooking device 82 in the high position, the carriage is driven along a path predefined by the control system.

[0043] In other embodiments not shown, the conveyor may be monorail or of another type used in overhead conveyor systems.

[0044] In the installation 1, the conveying of the transport devices 7 is done outside the treatment zone 5 at a certain speed defined by the treatment process to respect a certain rate, this speed is relatively high (typically 10 to 20 m / minute) compared to the speed of movement in the treatment zone 5. In the treatment zone to allow each product to receive the defined dose of the treatment and to ensure homogeneous treatment of all the products, it is necessary to ensure movement at another speed much slower (from only a few dm / minute to a few m / min) than in the rest of the circuit defined by the conveying system. It is also necessary to guarantee the stability of the transport devices 7 which can each have a plurality of shelves and have a high height, which therefore creates risks of tipping.

[0045] To ensure proper processing of the products carried by the transport devices 7, the latter can be moved by moving the carriages 8 by the traction chain 9 to the entrance of the processing zone 5, then the hooking device 82 can be moved to the low position so that the driving of the carriage by the traction chain 9 stops.

[0046] To ensure the driving and stability of the transport devices 7 in the treatment zone 5, the system comprises a secondary displacement and stabilization device arranged in said treatment zone 5. This device has driving means in the lower part configured to cooperate with securing means 71 which are provided in the lower part of each transport device 7.

[0047] The secondary displacement and stabilization device makes it possible to control the movement of the transport devices 7 in the treatment zone 5 according to a predetermined pitch depending on the articles to be treated and to ensure good stability. Indeed, the drive means, for example in the form of cleats, prevent the tilting of the transport devices during their movement at low speed defined by the movement pitch.

[0048] As shown in the example of [Fig.5], the secondary device comprises a lower chain 13 composed of links 131 and carrying drive means 132 in the form of cleats.

[0049] It may also comprise an upper chain 12 composed of links 121 and carrying additional drive means 122 also in the form of cleats. The additional cleats are configured to cooperate with additional guide means arranged in the upper part of the transport devices.

[0050] Advantageously, the upper chain 12 is synchronized with the lower chain 13. The synchronization between the upper chain 12 and the lower chain 13 can for example be carried out by a synchronization shaft 14. Alternatively, the synchronization can be carried out by an additional chain.

[0051] Advantageously, the movement of the lower chain is managed by a motor remote from the treatment zone. In [Fig.5] the motor being far from the zone 5 it is not visible, it is connected to the lower chain 13 by the means 16, which may comprise a chain or a transmission belt.

[0052] Furthermore, to ensure the centering of the transport device 7, the system may also comprise a lower guide rail 11 arranged to receive a centering element, arranged in the lower part of the transport devices 7.

[0053] The system may also comprise a transfer device 10 as shown in [Fig.2]. The device 10 is arranged to move the transport devices 7 from the waiting position, upstream of the treatment zone, to bring it into contact with the secondary device.

Claims

Claims

1. Conveying system of a set of multi-stage transport devices (7) capable of carrying articles intended to undergo treatment in a specific treatment zone (5), the conveying system comprising an overhead conveyor (6) having: - carriages (8) each carrying a suspended transport device (7), - a running track (64) on which said carriages (8) move, and - traction means (63, 9) capable of moving a carriage (8) to the entrance of the treatment zone (5) and from the exit of said treatment zone (5) at a first speed, the suspended transport device (7) having a lower end provided with securing means (71), the system further comprising a secondary device (12, 13,14) for movement arranged in said treatment zone and having drive means (132) in the lower part configured to cooperate with said securing means (71) to control the movement of said transport device (7) in said treatment zone (5) at a second speed lower than the first speed, in which the drive means comprise cleats (132), and in which the secondary device comprises: - a lower chain (13), and - an upper chain (12) comprising additional drive means (122) configured to secure with additional guide means arranged in the upper part of the transport devices (7), said upper chain (12) being synchronized with the lower chain (13).,

2. The system of claim 1, wherein the second speed is determined based on the items transported by the transport devices (7).

3. System according to the preceding claim in which the synchronization between the upper chain (12) and the lower chain (13) is carried out by a synchronization shaft (14).

4. System according to one of the preceding claims in which the movement of the lower chain (13) is managed by a motor remote from the treatment zone (5).

5. System according to one of the preceding claims, further comprising a lower guide rail (11) arranged to receive a centering element arranged in the lower part of a transport device (7).

6. System according to one of the preceding claims, further comprising a transfer device (10) arranged at the entrance to the treatment zone (5) and configured to move a transport device (7) from a waiting position, upstream of the treatment zone, to bring it into contact with the secondary device (12, 13).

7. Installation (1) for processing articles, comprising a conveying system according to one of the preceding claims.

8. Installation (1) according to the preceding claim, comprising means (3) for generating a beam (4) of X or Gamma radiation or electrons, used in the treatment zone (5).

9. Method for treating articles, implementing an installation according to one of claims 7 or 8.

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