System and Method for Controlling Access to Production Line Nests

Abstract

The invention relates to a system and method for controlling access to production line nests which include access request means, configured to send an access request signal when an automated guided supply vehicle reaches a predetermined distance to a nest vehicle access area; occupation detection means for detecting occupation inside the nest; connection means configured to allow or deny the vehicle access to the inside of the nest depending on whether said space is occupied and whether there is an incident on the production line, and means for opening and closing the parts collection area.

Claims

1. A system for controlling access to at least one nest of a production line, the nest comprising an inside space delimited by a barrier, a parts collection area and a vehicle access area, the production line comprising safety means configured to send signals of an incident when an incident is detected on the production line, the system comprising: access request means, configured to send an access request signal to the nest when an automated guided vehicle intending to stock the nest with assembly parts reaches a predetermined distance from the vehicle access area the automated guided vehicle being provided with an autonomous safety system configured to prevent the vehicle from moving when the autonomous safety system detects the proximity of an obstacle; occupation detection means, configured to detect whether the space inside the nest is occupied, and to emit an inoccupation signal in the case that the space inside the nest is not occupied, and to emit an occupation signal in the case that the space inside the nest is occupied; connection means configured so that once an inoccupation signal is received from the occupation detection means, the automated guided vehicle be connected to the safety means of the production line and configured to stop the automated guided vehicle in case of receiving a signal of an incident from the safety means of the production line; and means for opening and closing the parts collection area, connected to the connection means and configured to close the parts collection area before the vehicle enters the space inside the nest and to open the parts collection area when the vehicle has completed its access into the space inside the nest.

2. The system of claim 1, wherein the system further comprises at least one methacrylate door arranged in the vehicle access area and provided with at least one safety sensor, the safety sensor being configured to activate a safety alarm if the door is folded and to deny any access request until the safety alarm is reset and the occupation detection means confirm that the space inside the nest is not occupied.

3. The system of claim 1, wherein the access request means comprise a receiving photocell arranged in the vehicle access area and an emitting photocell arranged in the automated guided vehicle.

4. The system of claim 1, wherein the access request means comprise a receiving photocell arranged in the automated guided vehicle and an emitting photocell arranged in the vehicle access area.

5. The system of claim 1, wherein the access request means comprise an emitting/receiving photocell arranged in the vehicle access area and an optical reflection device arranged in the automated guided vehicle.

6. The system of claim 1, wherein the access request means comprise at least one inductive sensor connected to a programmable logic controller and a portion of ferrous material.

7. The system of claim 1, wherein the access request means comprise two photocells, the beams of which cross at one point, situated at the predetermined distance to the vehicle access area.

8. The system of claim 1, wherein the occupation detection means are provided with a safety laser scanner housed in the space inside the nest.

9. The system of claim 1, wherein the occupation detection means are provided with a photoelectric barrier arranged in the vehicle access area.

10. The system of claim 1, wherein the system further comprises: two metal profiles arranged in the vehicle access area to the nest, the ends of the metal profiles being arranged furthest from the nest at the same distance as the predetermined distance; and a pair of inductive sensors arranged in the automated guided vehicle, the inductive sensors being configured to detect the metal profiles and to inform the access request means when the metal profiles are detected.

11. The system of claim 1, wherein the connection means comprise a single beam emitter and a single beam receiver.

12. A method for controlling access to at least one nest of a production line, the nest comprising an inside space delimited by a barrier, a parts collection area and a vehicle access area, the production line comprising safety means configured to send signals of an incident when an incident is detected on the production line, the method comprising the following steps: sending an access request signal to the nest via access request means when a vehicle reaches a predetermined distance to the vehicle access area; verifying occupation detection means, in response to the access request signal to the nest and emitting with the occupation detection means an inoccupation signal in the case that the space inside the nest is not occupied and emitting an occupation signal in the case that the space inside the nest is occupied; after receiving an inoccupation signal emitted by the occupation detection means, connecting by means of connection means an automated guided vehicle to the safety means of the production line, and temporarily complementing an autonomous vehicle safety system via connection means, transmitting to it any incident that occurs on the production line; stopping, by means of the connection means, the automated guided vehicle in the case of receiving a signal of an incident from the safety means of the production line and, in the opposite case, allowing the automated guided vehicle access to the space inside the nest; and closing the parts collection area, with opening and closing means, before the connection means allow the vehicle to access the space inside the nest and opening the parts collection area when the vehicle has completed its access to the space inside the nest.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] To complete the present description of the invention, and for the purpose of helping to make the technical features of the invention more readily understandable, in accordance with preferred practical exemplary embodiments thereof, said description is accompanied by a set of drawings constituting an integral part of the same, which by way of illustration and not limitation represent the following:

[0046] FIG. 1 is a partially plan schematic view which shows a first embodiment of the system of the present invention;

[0047] FIG. 2 is a partially plan schematic view which shows a second embodiment of the system of the present invention;

[0048] FIG. 3 is a partially plan schematic view which shows a third embodiment of the system of the present invention;

[0049] FIG. 4 is a partially plan schematic view which shows a fourth embodiment of the system of the present invention;

[0050] FIG. 5 is a partially plan schematic view which shows a fifth embodiment of the system of the present invention; and

[0051] FIGS. 6a-6c are partially plan schematic views which show the access sequence of a supply vehicle to the space inside the nest.

NUMERICAL REFERENCE OF THE FIGURES

[0052] (1) Space inside the nest; [0053] (1a) Barrier of the nest; [0054] (1b) Parts collection area; [0055] (1c) Vehicle access area; [0056] (2a) Emitting photocell (of the access request means); [0057] (3a) Receiving photocell (of the access request means); [0058] (2b) Optical reflection device (of the access request means); [0059] (3b) Emitting/receiving photocell (of the access request means); [0060] (2c) Vehicle chassis-portion of ferrous material (of the access request means); [0061] (3c) Inductive sensors (of the access request means); [0062] (3d) Photocells (of the access request means); [0063] (3e) Programmable Logic Controller (PLC); [0064] (4a) Safety laser scanner (of the occupation detection means); [0065] (4b) Photoelectric barrier (of the occupation detection means); [0066] (5a) Inductive sensors; [0067] (5b) Metal profiles; [0068] (6) Means for opening and closing the parts collection area; [0069] (7a) Single beam receiver (of the connection means); [0070] (7b) Single beam emitter (of the connection means) [0071] (8) Doors; [0072] (8a) Door safety sensor; [0073] (9) Light beacon; [0074] (10) Security scanner in the nest; [0075] (15) Supply vehicle with an automated guided system (AGV); [0076] (20) Assembly robot; and [0077] (d) Predetermined distance at which the access request is made.

DESCRIPTION OF THE INVENTION

[0078] Throughout the present description, as well as in the attached figures, the elements with the same or similar functions will be designated with the same numerical references.

[0079] FIG. 1 shows a first embodiment of the system of the present invention. In this figure, one can see a nest comprising an inside space (1) delimited by a barrier (1a), a parts collection area (1b) (which a robot (20) accesses) and a vehicle access area (1c) (where a vehicle (15) accesses in the direction shown by the arrow).

[0080] In the vehicle access area (1c) there are two doors (8), controlled by two respective door control safety sensors (8a). When the doors (8) open, they act as barriers, preventing access to the space inside the nest (1) from the sides.

[0081] In this particular embodiment of the invention, the access request means comprise two emitting/receiving photocells (3b) provided in the access area (1c) and two optical reflection devices (2b) provided in the vehicle (15). Furthermore, connection means comprise a single beam emitter (7b) and a single beam receiver (7a). Also provided are means for opening and closing (6) the parts collection area.

[0082] In this embodiment of the invention, in addition to comprising a photoelectric barrier (4b), the occupation detection means comprise a safety laser scanner (4a).

[0083] FIG. 2 shows a second embodiment of the system of the present invention. In this particular case, the access request means comprise an emitting photocell (2a) provided in the vehicle (15). Furthermore, said emitting photocell (2a), when reaching the predetermined distance (d) to the vehicle access area (1c), emits a category 4 single beam access request which is received by the receiving photocell (3a). When receiving the access request signal, the occupation detection means (which, in this embodiment, comprise a photoelectric barrier (4b)), are activated.

[0084] The access control system herein shown further comprises connection means (7b) and (7a). Also provided are means for opening and closing (6) the parts collection area.

[0085] In practice, it is possible that, although the space inside the nest (1) is unoccupied (meaning no robot (20) or supply vehicle (15) has entered), in said inside space (1) there could be a container intended for storing, for example, assembly parts. To prepare for this situation, the present invention envisages the possibility that the occupation detection means (4a) can be calibrated in such a way that they understand the space inside the nest to be empty when they detect only the presence of said container.

[0086] FIG. 3 shows a third embodiment of the system of the present invention. In this particular case, the access request means comprise two inductive sensors (3c) situated at the predetermined distance (d). Furthermore, since the chassis (2c) of the vehicle (15) is made of ferrous material, when the vehicle (15) reaches said predetermined distance (d), the inductive sensors (3c) detect it, sending an access request signal to the PLC (3e).

[0087] FIG. 4 shows a fourth embodiment of the system of the present invention. In this particular case, the access request means comprise two photocells (3d), the beams of which cross at a point situated at the predetermined distance (d). This way, when the vehicle (15) reaches said predetermined distance (d), the two beams of the photocells (3d) stop crossing, this being the nest access request signal, which is then managed by the PLC (3e).

[0088] FIG. 5 shows a fifth embodiment of the system of the present invention. In this particular case, in the vehicle access area (1c) there are two metal profiles (5b) arranged in such a way that the ends of the metal profiles (5b) furthest from the nest are at the same distance as the predetermined distance (d). Furthermore, a pair of inductive sensors (5a) are arranged in the automated guided vehicle (15). This way, when the vehicle (15) reaches said predetermined distance (d), the inductive sensors detect the metal profiles, inform the access request means, the access request means then sending the corresponding access request signal to the nest.

[0089] In this embodiment of FIG. 5 the access request means comprise two emitting/receiving photocells (3b) arranged in the vehicle access area (1c) and two optical reflection devices (2b) arranged in the automated guided vehicle (15), likewise, they are provided with connection means (7b) and (7a) and means for opening and closing (6) the parts collection area.

[0090] FIGS. 6a-6c are views that schematically show the access sequence of a supply vehicle (15) to the space inside the nest (1).

[0091] FIG. 6a shows the vehicle (15) access procedure to the space inside the nest (1).

[0092] In the particular example herein shown, the access control system according to the invention is very similar to that shown in FIG. 1, the access request means having two emitting/receiving photocells (3b) and two optical reflection devices (2b).

[0093] In the example shown in FIG. 6A the vehicle (15) has reached the predetermined distance (d). This causes the beams emitted by the emitting/receiving photocells (3b) to reach the optical reflection means (2b) provided in the vehicle (15). As a result, the beams are reflected, returning the emitting/receiving photocells (3b) (as schematically illustrated by the corresponding dashed line). When the emitting/receiving photocells (3b) receive the previously emitted beams again, the system interprets that an access request has been received and the occupation detection means are activated, which comprise, in this specific example, a photoelectric barrier (4b).

[0094] If the photoelectric barrier (4b) were previously crossed by a vehicle (15) or if the door (8) were moved, when the vehicle (15) is situated at the distance (d), activating the safety sensors (8a), the light beacon (9) is then activated, and until the barrier (4b) and the door (8) are reset by an operator, the vehicle (15) will not have access.

[0095] If the photoelectric barrier (4b) has not been crossed, or if the door (8) has not been moved, or if the system has been reset, the area inside (1) the nest is secure and a signal is sent to the connection means (7a) and (7b).

[0096] The connection means connect the vehicle (15) to safety means of the production line, configured to send signals of an incident when an incident is detected on the production line.

[0097] Once an inoccupation signal is received from the occupation detection means, the connection means emitter (7b) sends a category 4 single beam to the connection means receiver (7a), thus connecting the safety means of the production line to the vehicle (15).

[0098] If there is no incident on the production line, the vehicle (15) can then access the inside of the nest (1) and, in turn, if there were an incident, the vehicle (15) would be immobile until the same were solved.

[0099] Said access movement is schematically shown by the arrow in FIG. 6a.

[0100] FIG. 6b is an optional step, in which the vehicle (15) has already accessed the space inside the nest (1). In the embodiment herein shown, a scanner (10) is provided, intended to secure the rear part of the vehicle (15) when it is inside (1) the nest.

[0101] In the example shown in FIG. 6C the vehicle (15) has already completed the tasks of stocking the parts and is proceeding to leave the inside (1) of the nest.

[0102] By going beyond the predetermined distance, the connection means cease to complement the safety of the vehicle (15), disconnecting the vehicle (15) from the safety means of the production line by interrupting the category 4 beam between the connection means (7a) and (7b), the vehicle (15) taking back its own safety system.

[0103] The present invention is not limited in any way by the embodiments herein disclosed. For a person skilled in the art, other possible embodiments that differ from those of the present invention will be evident in light of the present description. Thus, the scope of protection of the present invention is exclusively defined by the following claims.