Conveyance system

Abstract

The present invention addresses the problem of providing a conveyance system with which erroneous conveyance of an object is less likely to occur.　A conveyance system 1 for conveying a plurality of objects to be conveyed to destinations includes a conveyance state expecting means, a conveyance device 2, a plurality of sensors 5a, 5b, and a comparison means. The conveyance state expecting means expects an expected conveyance situation in which an object a to be conveyed is conveyed by the conveyance device 2. The conveyance device 2 has an actual object a to be conveyed thereon and actually moves the actual object a to be conveyed. The sensors 5a, 5b are located at predetermined positions and detect the actual object a to be conveyed on the conveyance device. The expected conveyance situation of the object a to be conveyed expected by the conveyance state expecting means and the actual conveyance situation of the actual object to be conveyed detected by the sensors 5a, 5b are compared by the comparison means.

Description

Transport System

[0001] The present invention relates to a conveying system that uses a conveyor device such as a roller conveyor or a belt conveyor.

[0002] Conveyor systems are often installed in delivery areas, collection points, warehouses, etc. For example, at delivery areas, it is necessary to sort transported items according to their destination, so the conveyor systems installed at delivery areas have multiple branched conveying paths. The conveyor systems installed at delivery areas have a main conveying path and branched conveying paths branching off from the main conveying path. A conveying direction changing device is installed at the branching point of the main conveying path.

[0003] JP 2005-231745 A JP 2012-211015 A JP 2013-230914 A

[0004] There is a market demand for faster transport of goods and an increase in the number of goods transported per unit time. To meet this demand, the inventors devised a conveying system in which the destinations of goods are determined in advance, goods are sent out in order, and when goods in a specific order arrive at a predetermined branching point, a conveying direction changing device is activated to send the goods to a branching conveying path. Specifically, if goods a are sent out to branching conveying path A, goods b are sent out to branching conveying path B, and goods c are sent out to branching conveying path B, the goods move along the main conveying path in the order of goods a, b, and c. Information indicating that the destination of the first goods a is branching conveying path A, the destination of the next goods b is branching conveying path B, and the destination of goods c is branching conveying path B is transmitted to the conveying direction changing devices at each branching point. In other words, the order in which the goods are sent and the destinations, such as the order in which the goods are to be transported, are associated and transmitted to the conveying direction changing devices at each branching point. When the article in the corresponding order reaches the branching point where it should change course, the conveying direction changing device is driven to send the article onto the branching conveying path.

[0005] In this conveying system, the conveying order and destination of the conveyed objects correspond to each other. According to the conveying system described above, there is no need to check the destination of the conveyed objects at the branching point, so conveying efficiency is high and the number of conveyed objects per unit time can be increased. However, in the conveying system described above, if an object being conveyed is removed, the correspondence between the conveying order and destination of the object is lost, resulting in incorrect conveyance. The same applies if another object is inserted midway along the conveying path, which breaks the correspondence between the conveying order and destination of the object, resulting in incorrect conveyance.

[0006] The present invention is intended to solve the above-mentioned problems and to propose a conveyance system that reduces the risk of erroneous conveyance of conveyed objects.

[0007] An aspect for solving the above-mentioned problem is a conveying system for conveying a plurality of conveyed objects to their respective destinations, comprising a conveying state estimation means, a conveying device, a plurality of sensors, and a comparison means, wherein the conveying state estimation means estimates an estimated conveying state in which the conveyed objects are conveyed by the conveying device, the conveying device places actual conveyed objects on it and actually moves the actual conveyed objects, the sensor is located at a predetermined position and detects the actual conveyed objects on the conveying device, and the comparison means compares the estimated conveying state of the conveyed objects estimated by the conveying state estimation means with the actual conveying state of the actual conveyed objects detected by the sensor.

[0008] The conveying system of this aspect includes a conveying state estimation means for estimating an estimated conveying state of the conveyed object as it is conveyed by the conveying device. The estimated conveying state is merely an estimate. The conveying system of this aspect also includes multiple sensors for detecting the actual conveying state of the conveyed object. In this conveying system, a comparison means compares the estimated conveying state of the conveyed object estimated by the conveying state estimation means with the actual conveying state of the conveyed object detected by the sensors, thereby reducing the risk of incorrect conveying of the conveyed object. For example, if an object being conveyed is removed, an unexpected gap will be created in the conveying path. That is, if there is a preceding first conveyed object and a following second and third conveyed objects, the intermediate second conveyed object will no longer be in its position, and the third conveyed object will be conveyed on the conveying path following the first conveyed object. Furthermore, if another conveyed object is inserted midway along the conveying path, an unexpected congestion will occur on the conveying path. That is, when there is a preceding first transported object and a following second transported object, if transported object X is inserted between the first and second transported objects, the third transported object will be transported along the transport path following the first transported object. If another transported object is inserted along the transport path, the intermediate second transported object will no longer be in its place, and the transported object X will be transported along the transport path following the first transported object, followed by the second transported object. The transport system of this aspect compares the estimated transport status of the transported objects estimated by the comparison means with the actual transport status of the actual transported objects. By comparing the two, unexpected empty spaces or unexpected congestion can be detected.

[0009] In the above-mentioned aspect, it is desirable that the transport state estimation means estimates the operation timing of the sensor under the estimated transport state, and has a driving state detection means, which detects the operation timing of the sensor under the actual driving state of the transport device.

[0010] According to this aspect, it is possible to compare the assumed transport situation with the actual transport situation.

[0011] In each of the above aspects, the transport state estimation means estimates the rotational state of a specific component and / or the time required to transport the transported item under the estimated transport state, and it is desirable that the means has a drive state detection means that detects the rotational state of a specific component and / or the time required to transport the transported item.

[0012] According to this aspect, the transport status of the transported object can be grasped.

[0013] In each of the above aspects, the conveying state estimation means estimates the conveying posture of the conveyed object as it is conveyed under the estimated conveying conditions, and at least one of the plurality of sensors is a sensor group, and the sensor group is made up of a plurality of sensor elements arranged in a direction intersecting the conveying direction of the conveyed object, and it is desirable that the parallel running and / or conveying posture of the conveyed object is detected as the actual conveying condition using information regarding the operation timing of each sensor element detected by each sensor element of the sensor group, and the conveying posture of the conveyed object estimated by the conveying state estimation means is compared with the actual parallel running and / or conveying posture of the conveyed object detected by the sensor using the comparison means.

[0014] "Parallel running of transported objects" refers to a state in which at least a portion of a plurality of transported objects is present in the same region of the transport path in the transport direction. Parallel running of transported objects also includes a case in which at least a portion of the transported objects are traveling side by side in the same region of the transport path in the transport direction as viewed in a plane. Transported objects also travel in a state in which they are stacked one on top of the other. According to this aspect, it is possible to detect situations in which the posture of the transported objects is distorted or the transported objects are being transported in parallel.

[0015] In each of the above-mentioned aspects, the conveying device has a conveying member that performs a rotating or running conveying operation, and moves the conveyed object by performing a conveying operation on the conveying member, the conveying state estimation means estimates a tip-side predicted conveying operation amount, which is the minimum value of the conveying operation amount that is expected when the tip of the conveyed object moves normally and is detected by a sensor at a predetermined position, and has a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and it is desirable that the comparison means performs a front end comparison to compare the actual conveying operation amount when the actual tip of the conveyed object is detected by a sensor at a predetermined position with the tip-side predicted conveying operation amount.

[0016] In the conveying system of this aspect, the predicted tip-side conveying operation amount is compared with the actual conveying operation amount. The predicted tip-side conveying operation amount is the expected operation amount of the conveying device when conveying the front end of the conveyed object through a specific section until it reaches the sensor position, and the minimum value of the conveying operation amount is used, taking into account errors, etc. Meanwhile, the drive status detection means acquires the actual conveying operation amount, which is the actual conveying operation amount of the conveying device. In the conveying system of this aspect, since the actual conveying operation amount is compared with the predicted tip-side conveying operation amount, the expected arrival time of the conveyed object is compared with the actual arrival time of the conveyed object, making it possible to detect unexpected empty spaces or unexpected congestion.

[0017] In each of the above-mentioned aspects, the conveying device has a conveying member that performs a rotating or running conveying operation, and moves the conveyed object by performing a conveying operation on the conveying member, the conveying state estimation means estimates a predicted conveying operation amount on the rear end side, which is the maximum conveying operation amount that is expected when the rear end of the conveyed object moves normally and is detected by a sensor at a predetermined position, and has a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and it is desirable that the comparison means performs a rear end comparison that compares the actual conveying operation amount when the actual rear end of the conveyed object is detected by a sensor at a predetermined position with the predicted conveying operation amount on the rear end side.

[0018] In the conveying system of this aspect, the predicted conveying operation amount of the rear end side is compared with the actual conveying operation amount. The predicted conveying operation amount of the rear end side is the predicted operation amount of the conveying device when conveying the rear end of the conveyed object through a specific section until it reaches the position of the sensor, and the maximum value of the conveying operation amount is used, taking into account errors, etc. Meanwhile, the drive status detection means acquires the actual conveying operation amount, which is the actual conveying operation amount of the conveying device. In the conveying system of this aspect, since the actual conveying operation amount is compared with the predicted conveying operation amount of the rear end side, the predicted arrival time of the rear end of the conveyed object is compared with the actual arrival time of the rear end of the conveyed object, making it possible to detect unexpected empty spaces or unexpected congestion.

[0019] In each of the above-mentioned aspects, the conveying device has a conveying member that performs a rotating or running conveying operation, and moves the conveying object by moving the conveying member, and the conveying state estimation means estimates a leading-end side predicted conveying operation amount, which is the minimum value of the conveying operation amount that is expected when the leading end of the conveyed object is detected by a sensor at a predetermined position when the object moves normally, and a trailing-end side predicted conveying operation amount, which is the maximum value of the conveying operation amount that is expected when the trailing end of the conveyed object is detected by a sensor at a predetermined position when the object moves normally, and has a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and it is desirable that the comparison means performs a leading-end comparison that compares the actual conveying operation amount when the leading end of the actual conveyed object is detected by a sensor at a predetermined position with the leading-end side predicted conveying operation amount, and a trailing-end comparison that compares the actual conveying operation amount when the trailing end of the actual conveyed object is detected by a sensor at a predetermined position with the trailing-end side predicted conveying operation amount.

[0020] In the conveying system of this embodiment, a front end comparison is performed to compare the predicted conveying operation amount at the front end with the actual conveying operation amount, and a rear end comparison is performed to compare the predicted conveying operation amount at the rear end with the actual conveying operation amount, so that the expected conveying situation can be compared more accurately with the actual conveying situation of the actual conveyed item.

[0021] In each of the above-described aspects, if the comparison by the comparison means shows a difference of a certain amount between the estimated transport status and the actual transport status, it is desirable to perform at least one of the following processes: (1) change the transport speed of the transport device; (2) correct the estimated transport status of the transport status estimation means; (3) change the destination of the transported object; (4) stop the transport device; (5) change the transport route; or (6) issue a notification.

[0022] "Changing the conveying speed of the conveying device" may involve changing the speed of the entire conveying device, or changing the speed of a certain section of the conveying device. "Correction of the estimated conveying status of the conveying status estimation means" is a measure taken when it is thought that the estimated conveying status is unrealistic. "Changing the destination of the conveyed item" may involve, for example, returning the conveyed item to its initial position. Or, for example, changing the destination to a manual sorting location so that it can be sorted manually by an operator. "Stopping the conveying device" may involve stopping the entire conveying device, or may involve stopping a certain section of the conveying device. "Changing the conveying route" involves detouring the conveyed item to its specified destination. "Notification" is given by sound, light, text, etc.

[0023] Another aspect for solving a similar problem is a conveying system that conveys multiple objects to their respective destinations using a conveying device, wherein the conveying device has a conveying member that performs a rotating or running conveying operation, and moves the objects by causing the conveying member to perform a conveying operation, and the conveying system is characterized by having a tip-side prediction means that predicts a tip-side predicted conveying operation amount, which is the minimum value of the conveying operation amount that is expected when the tip of the object to be conveyed is detected by a sensor at a predetermined position when the object moves normally, a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and a front end comparison means that compares the actual conveying operation amount with the tip-side predicted conveying operation amount when the actual tip of the object to be conveyed is detected by a sensor at a predetermined position.

[0024] In this type of conveying system, the actual conveying operation amount is compared with the predicted conveying operation amount at the tip side, so that the expected arrival time of the conveyed item is compared with the actual arrival time of the conveyed item, making it possible to identify unexpected vacancies or unexpected congestion.

[0025] Another aspect for solving a similar problem is a conveying system that conveys multiple transported items to their respective destinations using a conveying device, wherein the conveying device has a conveying member that performs a rotating or running conveying operation, and moves the transported items by causing the conveying member to perform a conveying operation, and the conveying system is characterized by having a rear end side prediction means that predicts a rear end side predicted conveying operation amount, which is the maximum conveying operation amount that is expected when the rear end of the transported item moves normally and is detected by a sensor at a predetermined position, a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and a rear end comparison means that compares the actual conveying operation amount with the rear end side predicted conveying operation amount when the actual rear end of the transported item is detected by a sensor at a predetermined position.

[0026] In the conveying system of this embodiment, the actual conveying operation amount is compared with the predicted conveying operation amount on the rear end side, so that the expected arrival time of the rear end of the conveyed object is compared with the actual arrival time of the rear end of the conveyed object, making it possible to identify unexpected empty spaces or unexpected congestion.

[0027] Another aspect for solving a similar problem is a conveying system that conveys multiple conveyed objects to their respective destinations using a conveying device, the conveying device having a conveying member that performs a rotating or running conveying operation, and moving the conveyed objects by performing a conveying operation on the conveying member, and the conveying system is characterized by having a leading edge prediction means that predicts a leading edge predicted conveying operation amount, which is the minimum value of the conveying operation amount that is expected when the leading edge of the conveyed object is detected by a sensor at a predetermined position when the object moves normally, a trailing edge prediction means that predicts a trailing edge predicted conveying operation amount, which is the maximum value of the conveying operation amount that is expected when the trailing edge of the conveyed object is detected by a sensor at a predetermined position when the object moves normally, a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, a leading edge comparison means that compares the actual conveying operation amount with the leading edge predicted conveying operation amount when the actual leading edge of the conveyed object is detected by the sensor at the predetermined position, and a trailing edge comparison means that compares the actual conveying operation amount with the trailing edge predicted conveying operation amount when the actual trailing edge of the conveyed object is detected by the sensor at the predetermined position.

[0028] In the conveying system of this embodiment, a front end comparison is performed to compare the predicted conveying operation amount at the front end with the actual conveying operation amount, and a rear end comparison is performed to compare the predicted conveying operation amount at the rear end with the actual conveying operation amount, so that the expected conveying situation can be compared more accurately with the actual conveying situation of the actual conveyed item.

[0029] In the above-mentioned aspect, at least one of the plurality of sensors is a sensor group, and the sensor group is characterized in that a plurality of sensor elements are arranged in a direction intersecting the conveying direction of the transported object.

[0030] According to this aspect, the conveyance system uses the sensor group to recognize the state of the conveyed object in a planar manner, and can know the shape, conveyance posture, parallel running status, etc. According to this aspect, it is possible to detect situations where the posture of the conveyed object is distorted or where the conveyed objects are being conveyed in parallel.

[0031] In each of the above aspects, it is desirable that the drive status detection means be capable of performing a detection operation to detect late or early arrival of the transported item using information regarding the operation timing of the sensor element detected by each sensor element of the sensor group.

[0032] According to this aspect, by detecting the delay or early arrival of the transported goods, it is possible to know the unexpected gap between transported goods or the unexpected congestion.

[0033] In each of the above aspects, it is desirable that the drive status detection means be capable of performing a detection operation to detect the parallel running and / or conveying posture of the transported object using information regarding the operation timing of the sensor element detected by each sensor element of the sensor group.

[0034] According to this aspect, it is also possible to perform a detection operation to detect abnormal situations such as unexpected parallel running of transported objects or changes in posture.

[0035] In each of the above-described aspects, it is desirable that a driving status detection means is provided, and that the driving status detection means detects the rotation status of a specific member and / or the time required to transport the transported object.

[0036] According to this aspect, the transport status of the transported object can be grasped.

[0037] In each of the above-described aspects, the conveying system is characterized in that the parallel running of the conveyed objects is eliminated or the conveying posture is changed based on the result of the detection operation.

[0038] According to this aspect, parallel running of transported objects can be prevented and transported in a preferred posture.

[0039] In each of the above aspects, when an abnormality is detected due to delayed or early arrival of the transported item, or removal or insertion, it is desirable to reset the deviation between the expected transport situation and the actual transport situation and re-set the expected transport situation to match the detected actual transport situation.

[0040] According to this aspect, when an abnormality is detected due to a delayed or early arrival of a transported item, or due to removal or insertion, it is possible to reset (reconfigure) the expected transport situation to a situation that is close to the actual transport situation.

[0041] In each of the above-mentioned aspects, when an object is transported from one transport module to another in two adjacent transport modules, it is desirable to reset the deviation between the expected transport situation and the actual transport situation and re-set the expected transport situation to the detected actual transport situation.

[0042] In each of the above aspects, it is desirable to reset the estimated conveyance situation in accordance with the detected actual conveyance situation after the conveyance object reaches or passes the sensor.

[0043] According to this aspect, the estimated transport situation is constantly updated, and an estimated transport situation that does not deviate significantly from the actual transported object can be obtained, making control easy.

[0044] Another aspect for solving a similar problem is a conveying system for conveying multiple objects to their respective destinations, comprising a conveying device, multiple sensors, and a comparison means, wherein the conveying device is configured to load actual objects and actually move the actual objects, at least one of the multiple sensors is a sensor group, wherein the sensor group is configured to have multiple sensor elements arranged in a direction intersecting the conveying direction of the objects, and wherein the parallel running and / or conveying posture of the objects is detected using information detected by each sensor element of the sensor group regarding the operation timing of the sensor element, and the normal conveying posture of the objects is compared with the actual parallel running and / or conveying posture of the objects detected by the sensors using the comparison means.

[0045] According to the transport system of this aspect, the transport status of the transported object can be grasped and compared with the normal transport status by the comparison means.

[0046] In each of the above aspects, it is desirable that the conveying device has a conveying path that branches into a plurality of paths, has a plurality of conveying destinations, and the conveying order of the objects corresponds to the destinations of the objects.

[0047] According to the conveying system of this aspect, there is no need to check the destination of the transported article at the branching section, so that the transport efficiency is high and the number of transported articles per unit time can be increased.

[0048] The conveying system of the present invention reduces the occurrence of erroneous conveyance of conveyed objects.

[0049] 1 is a conceptual diagram of a conveying system according to an embodiment of the present invention, where (a) is the conveying line assumed by the conveying state assumption means, and (b) is the actual conveying line. FIG. 1 is a conceptual diagram of a conveying system according to an embodiment of the present invention, showing a state in which conveyed objects a, b, and c are conveyed by the conveying system, where (a) is the conveying line assumed by the conveying state assumption means, and (b) is the actual conveying line. FIG. 1 is a conceptual diagram of a conveying system according to an embodiment of the present invention, showing a state in which conveyed objects a, b, and c are conveyed by the conveying system, showing a state subsequent to FIG. 2, where (a) is the conveying line assumed by the conveying state assumption means, and (b) is the actual conveying line. FIG. 2 is a conceptual diagram of a conveying system according to an embodiment of the present invention, showing a state in which conveyed objects a, b, and c are conveyed by the conveying system, showing a state subsequent to FIG. 3, where (a) is the conveying line assumed by the conveying state assumption means, and (b) is the actual conveying line. 1A to 1E are conceptual diagrams of a conveying system according to an embodiment of the present invention, showing the state in which conveyed objects a, b, and c are conveyed by the conveying system, the state following FIG. 4, where (a) is the conveying line assumed by the conveying state assumption means, and (b) is the actual conveying line. A block diagram of a central control device of a conveying system according to an embodiment of the present invention. A conceptual diagram of a specific 26 of a conveying system according to an embodiment of the present invention, where (a) is the conveying module assumed by the conveying state assumption means, and (b) is the actual conveying module. A conceptual diagram of a specific section of a conveying system according to an embodiment of the present invention, showing a case in which conveyed objects pass through the section as expected, where the upper diagrams of (a) to (e) are the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) are the actual conveying line. A conceptual diagram of a specific section of a conveying system according to an embodiment of the present invention, showing a case in which conveyed objects pass through the section normally, although moving slightly faster, where the upper diagrams of (a) to (e) are the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) are the actual conveying line. 1A to 1F are conceptual diagrams of a specific section of a conveying system according to an embodiment of the present invention, showing the case in which the conveyed object passes through the section normally, although moving somewhat slowly. The upper diagrams in (a) to (f) are the conveying line assumed by the conveying state assumption means, and the lower diagrams in (a) to (f) are the actual conveying line.

[0023] The following are conceptual diagrams of a specific section of a conveying system according to an embodiment of the present invention, showing a case where an object passes through the section while proceeding too quickly, with the upper diagrams of (a) to (e) representing the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) representing the actual conveying line.

[0024] The following are conceptual diagrams of a specific section of a conveying system according to an embodiment of the present invention, showing a case where an object passes through the section while proceeding too slowly, with the upper diagrams of (a) to (e) representing the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) representing the actual conveying line.

[0025] The following are conceptual diagrams of a specific section of a conveying system according to an embodiment of the present invention, showing a case where an object is removed midway, with the upper diagrams of (a) to (e) representing the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) representing the actual conveying line. 1A to 1E are conceptual diagrams of a specific section of a conveying system according to an embodiment of the present invention, illustrating a case where an unexpected object is introduced midway, with the upper diagrams of (a) to (e) illustrating the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) illustrating the actual conveying line. 1B is a conceptual diagram of a specific section of a conveying system according to another embodiment of the present invention, illustrating a case where an object is removed midway, with the upper diagrams of (a) to (e) illustrating the conveying line assumed by the conveying state assumption means, and the lower diagrams of (a) to (e) illustrating the actual conveying line. 1C is an explanatory diagram illustrating the relationship between the monitoring section, the size of the object, and the predicted conveying movement amount at the leading end and the predicted conveying movement amount at the trailing end. 1D is a conceptual diagram of a conveying system according to a second embodiment of the present invention, illustrating an actual conveying line. 1E is a perspective view of a sensor unit (sensor group). 1D and (b) are explanatory diagrams illustrating a state where objects are traveling side by side. 1D is a block diagram of a central control device of a conveying system according to a second embodiment of the present invention. A conceptual diagram showing a plan view of a portion of the conveying device of the second embodiment, illustrating the operation when the object is conveyed in a position parallel to the conveying direction, where (a1) and (a2) are figures showing the movement of the actual object on the conveying device, (b1) and (b2) are figures showing the sensor image on the conveying device, (c1) and (c2) are figures showing the appearance and shape of the object derived from the sensor image at the time of reset, and (d1) and (d2) are figures showing the movement of the virtual object on the conveying device.22 is a conceptual diagram of a part of the conveying device viewed from above, showing a continuation of the operation from FIG. 21 , (a3) ​​and (a4) are diagrams showing the movement of an actual conveyed object on the conveying device, (b3) and (b4) are diagrams showing a sensor image on the conveying device, (c3) and (c4) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d3) and (d4) are diagrams showing the movement of a virtual conveyed object on the conveying device. A conceptual diagram of a part of the conveying device viewed from above, showing an operation when the attitude of the conveyed object is inclined, (a1) and (a2) are diagrams showing the movement of an actual conveyed object on the conveying device, (b1) and (b2) are diagrams showing a sensor image on the conveying device, (c1) and (c2) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d1) and (d2) are diagrams showing the movement of a virtual conveyed object on the conveying device. 24 is a conceptual diagram showing a part of the conveying device in a plan view, showing a continuation of the operation from Fig. 23, where (a3) ​​and (a4) are figures showing the movement of an actual conveyed object on the conveying device, (b3) and (b4) are figures showing a sensor image on the conveying device, (c3) and (c4) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d3) and (d4) are figures showing the movement of a virtual conveyed object on the conveying device. 24 is a conceptual diagram showing a part of the conveying device in a plan view, showing a continuation of the operation from Fig. 24, where (a5) and (a6) are figures showing the movement of an actual conveyed object on the conveying device, (b5) and (b6) are figures showing the sensor image on the conveying device, (c5) and (c6) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d5) and (d6) are figures showing the movement of a virtual conveyed object on the conveying device. A conceptual diagram showing a plan view of a portion of the conveying device of the second embodiment, illustrating a situation in which two overlapping objects are being conveyed, where (a1) and (a2) are diagrams showing the movement of actual objects on the conveying device, (b1) and (b2) are diagrams showing sensor images on the conveying device, (c1) and (c2) are diagrams showing the appearance and shape of the objects derived from the sensor image at reset, and (d1) and (d2) are diagrams showing the movement of virtual objects on the conveying device.27 is a conceptual diagram showing a part of the conveying device in a plan view, showing a continuation of the operation from Fig. 26, where (a3) ​​and (a4) are figures showing the movement of an actual conveyed object on the conveying device, (b3) and (b4) are figures showing a sensor image on the conveying device, (c3) and (c4) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d3) and (d4) are figures showing the movement of a virtual conveyed object on the conveying device. 27 is a conceptual diagram showing a part of the conveying device in a plan view, showing a continuation of the operation from Fig. 27, where (a5) and (a6) are figures showing the movement of an actual conveyed object on the conveying device, (b5) and (b6) are figures showing the sensor image on the conveying device, (c5) and (c6) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d5) and (d6) are figures showing the movement of a virtual conveyed object on the conveying device. 29 is a conceptual diagram of a part of the conveying device in a plan view showing a situation in which a preceding conveyed object is pushed and conveyed by a succeeding conveyed object, (a1) and (a2) are diagrams showing the movement of the actual conveyed object on the conveying device, (b1) and (b2) are diagrams showing sensor images on the conveying device, (c1) and (c2) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d1) and (d2) are diagrams showing the movement of the virtual conveyed object on the conveying device. 29 is a conceptual diagram of a part of the conveying device in a plan view showing a continuation of the operation from FIG. 29, (a3) ​​and (a4) are diagrams showing the movement of the actual conveyed object on the conveying device, (b3) and (b4) are diagrams showing sensor images on the conveying device, (c3) and (c4) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d3) and (d4) are diagrams showing the movement of the virtual conveyed object on the conveying device. A conceptual diagram of a portion of the conveying device of the second embodiment viewed from above, showing the operation when the posture of the conveyed object changes during conveyance, (a1) and (a2) are figures showing the movement of the actual conveyed object on the conveying device, (b1) and (b2) are figures showing the sensor image on the conveying device, (c1) and (c2) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d1) and (d2) are figures showing the movement of the virtual conveyed object on the conveying device.It is a conceptual diagram of a part of the conveying device as viewed from above in a plan view, showing the continuation of the operation from FIG. 31. (a3) and (a4) are diagrams showing the movement of the actual conveyed object on the conveying device, (b3) and (b4) are diagrams showing the sensor image on the conveying device, (c3) and (c4) are diagrams showing the posture and shape of the conveyed object derived from the sensor image at the time of reset, and (d3) and (d4) are diagrams showing the movement of the virtual conveyed object on the conveying device. It is a conceptual diagram of a part of the conveying device as viewed from above in a plan view, showing the continuation of the operation from FIG. 32. (a5) and (a6) are diagrams showing the movement of the actual conveyed object on the conveying device, (b5) and (b6) are diagrams showing the sensor image on the conveying device, (c5) and (c6) are diagrams showing the posture and shape of the conveyed object derived from the sensor image at the time of reset, and (d5) and (d6) are diagrams showing the movement of the virtual conveyed object on the conveying device. It is a conceptual diagram of a part of the conveying device as viewed from above in a plan view, showing the continuation of the operation from FIG. 33. (a7) and (a8) are diagrams showing the movement of the actual conveyed object on the conveying device, (b7) and (b8) are diagrams showing the sensor image on the conveying device, (c7) and (c8) are diagrams showing the posture and shape of the conveyed object derived from the sensor image at the time of reset, and (d7) and (d8) are diagrams showing the movement of the virtual conveyed object on the conveying device. It is a conceptual diagram of a part of the conveying device as viewed from above in a plan view, showing the continuation of the operation from FIG. 34. (a9) and (a10) are diagrams showing the movement of the actual conveyed object on the conveying device, (b9) and (b10) are diagrams showing the sensor image on the conveying device, (c9) and (c10) are diagrams showing the posture and shape of the conveyed object derived from the sensor image at the time of reset, and (d9) and (d10) are diagrams showing the movement of the virtual conveyed object on the conveying device. It is a conceptual diagram of a part of the conveying device of the second embodiment as viewed from above in a plan view, showing a situation where the subsequent conveyed object rides on top of the preceding conveyed object after the preceding conveyed object stops, and the two conveyed objects are conveyed while overlapping. (a1) and (a2) are diagrams showing the movement of the actual conveyed object on the conveying device, (b1) and (b2) are diagrams showing the sensor image on the conveying device, (c1) and (c2) are diagrams showing the posture and shape of the conveyed object derived from the sensor image at the time of reset, and (d1) and (d2) are diagrams showing the movement of the virtual conveyed object on the conveying device.36 is a conceptual diagram showing a part of the conveying device in a plan view from above, showing a continuation of the operation from Fig. 36, where (a3) ​​and (a4) are figures showing the movement of an actual conveyed object on the conveying device, (b3) and (b4) are figures showing a sensor image on the conveying device, (c3) and (c4) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d3) and (d4) are figures showing the movement of a virtual conveyed object on the conveying device. 34 is a conceptual diagram showing a part of the conveying device in a plan view from above, showing a continuation of the operation from Fig. 34, where (a5) and (a6) are figures showing the movement of an actual conveyed object on the conveying device, (b5) and (b6) are figures showing the sensor image on the conveying device, (c5) and (c6) are figures showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d5) and (d6) are figures showing the movement of a virtual conveyed object on the conveying device. 38 is a conceptual diagram of a portion of the conveying device viewed from above, showing a continuation of the operation from FIG. 38, (a7) and (a8) are diagrams showing the movement of an actual conveyed object on the conveying device, (b7) and (b8) are diagrams showing a sensor image on the conveying device, (c7) and (c8) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d7) and (d8) are diagrams showing the movement of a virtual conveyed object on the conveying device. A conceptual diagram of a portion of the conveying device of the second embodiment viewed from above, showing a situation in which a leading conveyed object is pushed by a following conveyed object after the leading conveyed object has stopped, (a1) and (a2) are diagrams showing the movement of an actual conveyed object on the conveying device, (b1) and (b2) are diagrams showing the sensor image on the conveying device, (c1) and (c2) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d1) and (d2) are diagrams showing the movement of a virtual conveyed object on the conveying device. A conceptual diagram of a portion of the conveying device viewed from above, showing a continuation of the operation from Figure 40, where (a3) ​​and (a4) are figures showing the movement of the actual conveyed object on the conveying device, (b3) and (b4) are figures showing the sensor image on the conveying device, (c3) and (c4) are figures showing the appearance and shape of the conveyed object derived from the sensor image at reset, and (d3) and (d4) are figures showing the movement of the virtual conveyed object on the conveying device.42 is a conceptual diagram of a portion of the conveying device viewed from above, showing a continuation of the operation from FIG. 41, where (a5) and (a6) are diagrams showing the movement of an actual conveyed object on the conveying device, (b5) and (b6) are diagrams showing a sensor image on the conveying device, (c5) and (c6) are diagrams showing the appearance and shape of the conveyed object derived from the sensor image at the time of reset, and (d5) and (d6) are diagrams showing the movement of a virtual conveyed object on the conveying device. A perspective view showing an example of a conveying module including a plurality of conveying cells, each capable of assigning a different conveying direction to the other conveying cell.

[0050] An embodiment of the present invention will now be described. The conveying system 1 of this embodiment includes a real conveyor line 25 having a layout as shown in FIG. 1B and a central control device 3. The conveyor line 25 includes a conveying device 2 consisting of a roller conveyor and multiple section sensors 5. The conveying device 2 is configured by connecting multiple well-known conveying modules 6. The conveying modules 6 are also called zone conveyors and are short roller conveyors. The conveying modules 6 of the conveying device 2 are driven by motors (not shown). The conveying modules 6 are equipped with individual control devices 7 called zone controllers, and the rollers 26 ( FIG. 7 ) belonging to the conveying modules are driven and stopped by the individual control devices 7. That is, the motors of the conveying modules 6 of the conveying device 2 are controlled by the individual control devices 7. In this embodiment, the individual control devices 7 belonging to each conveying module 6 output pulses corresponding to the rotation of the motor.

[0051] The transport module 6 is equipped with a load sensor 45 (Figure 7). The transport modules 6 of the transport device 2 are driven individually to move the transported object forward (from left to right in the drawing, as indicated by the arrow). That is, when an object is introduced into the upstream transport module 6, that transport module 6 and the transport module 6 ahead of it in the travel direction are driven to move the object forward. This operation is repeated sequentially to move the transported object.

[0052] As shown in Figure 1(b), the conveyor line 25 has one main conveying path 10 and multiple branch conveying paths branching off from the main conveying path. A conveying direction changer (not shown) is provided at each branch point. For ease of illustration, only branch conveying paths A and B are shown. The area at the start of the main conveying path 10 is a preparation area 50, and beyond that is a conveying area 51.

[0053] A plurality of section sensors (sensors) 5 are installed at regular intervals on the conveyor line 25. The type of section sensor 5 is not limited, but an optical sensor, for example, can be used. For example, a transmission-type optical sensor equipped with a pair of a light emitter and a light receiver can be used as the section sensor 5. When a transmission-type optical sensor is used, the light emitter is installed on one side of the conveyor line 25 and the light receiver is installed on the other side. The section sensor 5 used in this embodiment is a single sensor. The section sensor 5 used in this embodiment determines whether or not there is an object being transported in front of the section sensor 5, and in this embodiment, the section sensor 5 detects the leading and trailing edges of the object being transported. In other words, the section sensor 5 used in this embodiment determines whether or not there is something between the light emitter and the light receiver.

[0054] An information reading means 8 is provided in the preparation area 50 of the conveyor line 25. The information reading means 8 is a device that reads information from a barcode, two-dimensional code, or the like attached to the transported object. The structure and principle of the information reading means 8 are not limited, and it may be a device that reads information optically, or a device that uses magnetism or radio waves. For example, the information reading means 8 may be a code reader that reads two-dimensional codes or a barcode reader that reads barcodes. The information reading means 8 may also be a device that reads information from an information storage member such as an RFID. The transport system 1 of this embodiment has a total length measuring means that measures the total length of the transported object at the start of transport.

[0055] In this embodiment, as will be described later, the first section sensor 5a measures the total length of the transported object at the start of transport. However, the present invention is not limited to this configuration, and a separate sensor may be used to measure the total length of the transported object at the start of transport. As a modified example, for example, the information reading means 8 may be provided with a measurement sensor (not shown) that measures the length of the transported object. At the end of the conveyor line 25 is a manual work area 27. The manual work area 27 is a work area where workers sort the objects manually.

[0056] Next, the central control device 3 will be described. The central control device 3 is equipped with a CPU and memory, and stores computer programs that realize desired functions. As shown in FIG. 6, the central control device 3 of this embodiment stores computer programs that functionally correspond to the conveyor control means 11, conveyance state estimation means 12, drive status detection means 13, comparison means 28, reset means 16, and conveyed object length measurement means 18. Signals from the section sensor 5, the information reading means 8, and each conveyance module 6 are input to the central control device 3. The conveyance module 6 and a display device 17 are connected to the output side of the information reading means 8.

[0057] The conveyor control means 11 controls the conveying device 2, and in addition to its normal control functions, is equipped with a transported article information storage means 30 and a destination setting means 31. The transported article information storage means 30 stores information about the type of transported article and its destination. The destination setting means 31 determines the destination of the transported article from the information in the transported article information storage means 30 and determines the transport route.

[0058] The conveyance state estimation means 12 estimates and determines the conveyance state of the conveyed object using a computer. The conveyance state estimation means 12 particularly functions as an estimated pulse calculation means 35, a leading end side estimated conveyance operation amount determination means 36, and a trailing end side estimated conveyance operation amount determination means 37. Specifically, the conveyance state estimation means 12 determines when and to what position on the conveyor line 25 each conveyed object should reach.

[0059] The transport state estimation means 12 will be described below. The bottom diagram in each diagram in Fig. 8 is the actual transport device 2. Hereinafter, the bottom diagram in each diagram will be referred to as the actual transport device 2. The actual transport device 2 depicted at the bottom of each diagram in Fig. 8 is a schematic representation of the area between two section sensors 5a and 5b. The top diagram in each diagram in Fig. 8 is a virtual transport device 102, which has virtual section sensors 105a and 105b in accordance with the actual transport device 2. Hereinafter, the top diagram in each diagram will be referred to as the virtual transport device 102. The virtual transport device 102 is a replica of the actual transport device 2.

[0060] The conveyance state estimating means 12 determines the position of the conveyed object a at a certain timing, for example, as shown in the upper diagram of each diagram in Figure 8. In each virtual conveyance device 102 in Figure 8, the solid line indicates the position where the conveyed object should be at each timing. For ease of understanding, the conveyed object whose position is determined by the conveyance state estimating means is referred to as virtual conveyance object a. Furthermore, the actual conveyance object is referred to as actual conveyance object a. For ease of understanding, the virtual conveyance object a and the actual conveyance object a are displayed at the same ratio.

[0061] In this embodiment, taking into account disturbances within the expected range during transport, the virtual transport device 102 defines a range slightly larger than the actual transported object a, and determines the range of positions that the actual transported object a should be in at what time. In the virtual transport device 102 shown in FIG. 8( b), the two-dot chain line surrounding the virtual transported object a is the presence area 15 where the virtual transported object a should be. The size of the presence area 15 is not limited, but is approximately 1.05 to 1.3 times the total length of the virtual transported object a. More preferably, it is approximately 1.08 to 1.15 times. FIG. 7 shows an enlarged view of each virtual transport device 102 and the actual transport device 2 at a specific position. The line at the front end of the presence area 15 is the front limit line 20. The line at the rear end is the rear limit line 21. The transport state estimation means 12 simulates the ideal movement of the transported object, and as shown in FIG. 8, the virtual transported object a and the surrounding presence area 15 move over time.

[0062] The leading-end predicted conveyance operation amount determining means 36 and the trailing-end predicted conveyance operation amount determining means 37 determine the allowable range of the drive amount of the conveyance device 2 while the virtual conveyed object a passes through the two section sensors 105a and 105b in the virtual space. Specifically, the real conveyance device 2 is a roller conveyor, and the real conveyed object a is placed on the rollers 26. The real conveyed object a moves as the rollers rotate. The conveyance state estimating means 12 moves the virtual conveyed object a between the two section sensors 105a and 105b in the virtual space. The central control device 3 then calculates the estimated drive status of the rollers 26 when the virtual conveyed object a passes through the two virtual section sensors 105a and 105b. Specifically, the central control device 3 calculates a value related to the number of rotations of the rollers 26 required for the virtual conveyed object a to pass through the two virtual section sensors 105a and 105b. The number of rotations of the roller 26 specifically correlates with the motor pulse of the conveying device 2, and in this embodiment, the motor pulse is calculated as a value related to the required number of rotations of the roller 26.

[0063] Next, the leading-end side predicted conveyance operation amount determining means 36 and the trailing-end side predicted conveyance operation amount determining means 37 will be described. For ease of explanation, the section sensor 5a on the upstream side in the direction of travel of the real conveyance device 2 will be referred to as the first section sensor 5a, and the section sensor 5b on the downstream side will be referred to as the second section sensor 5b. Furthermore, the section sensor 105a on the upstream side in the direction of travel of the virtual conveyance device 102 will be referred to as the virtual first section sensor 105a, and the section sensor 105b on the downstream side will be referred to as the virtual second section sensor 105b. In this embodiment, the estimated pulse calculating means 35 and the leading-end side predicted conveyance operation amount determining means 36 calculate the number of roller rotations required from when the leading end of the virtual conveyed object a is detected by the virtual first section sensor 105a until the front limit line 20 is detected by the virtual second section sensor 105b. The required number of rotations is converted into motor pulses. As described above, since the virtual conveying device 102 is a simulation of the actual conveying device 2, the leading end side predicted conveying operation amount determination means 36 calculates the number of roller rotations required from the time the leading end of the actual conveyed item a is detected by the first section sensor 5a until it reaches the second section sensor 5b.

[0064] Similarly, the estimated pulse calculation means 35 and the trailing end side estimated conveying operation amount determination means 37 calculate the number of roller rotations required from when the leading edge of the virtual conveyed object a is detected by the virtual first section sensor 105a until the rear limit line 21 is detected by the virtual second section sensor 105b. As described above, since the virtual conveying device 102 simulates the actual conveying device 2, the trailing end side estimated conveying operation amount determination means 37 calculates the number of roller rotations required from when the leading edge of the actual conveyed object a is detected by the first section sensor 5a until it reaches the second section sensor 5b.

[0065] Since the front limit line 20 is ahead of the leading edge of the virtual transported object a, the motor pulses required for the front limit line 20 to reach the virtual second section sensor 105b are fewer than the motor pulses required for the leading edge of the virtual transported object a to reach the virtual second section sensor 105b. The motor pulses (amount of conveying movement) required from the time when the leading edge of the virtual transported object a is assumed to be detected by the virtual first section sensor 105a until the time when the front limit line 20 is assumed to be detected by the virtual second section sensor 105b is the minimum value of the assumed range (allowable range) of motor pulses (amount of conveying movement) expected to be detected by the real second section sensor 5b from the time when the leading edge of the actual transported object a is detected by the real first section sensor 5a in the case of normal movement.

[0066] In this embodiment, the leading-end side predicted conveying operation amount determining means 36 determines the motor pulses required from when the leading end of the virtual conveyed article a is detected by the virtual first section sensor 105a until the front limit line 20 is detected by the virtual second section sensor 105b. That is, in this embodiment, it is assumed that the conveyed article a moves normally, and the leading-end side predicted conveying operation amount determining means 36 determines the minimum value (allowable value) of the motor pulses (conveying operation amount) that are expected to be required from when the leading end of the actual conveyed article a is detected by the first section sensor 5a until the leading end of the actual conveyed article a is detected by the second section sensor 5b.

[0067] Hereinafter, the minimum value (allowable value) of the motor pulses (amount of conveying movement) that are expected to be detected by the second section sensor 5b after the leading edge of the actual conveyed object a determined by the leading edge side expected conveying movement amount determining means 36 is detected by the first section sensor 5a will be referred to as the leading edge arrival expected pulse. The leading edge arrival expected pulse is the leading edge side expected conveying movement amount, which is the minimum value of the conveying movement amount that is expected to be detected by the second section sensor 5b when the leading edge of the conveyed object a moves normally. The leading edge arrival expected pulse is determined by calculation and is not actual. Based on the history of the leading edge arrival expected pulse, the leading edge arrival expected pulse is the minimum value of the motor pulses (amount of conveying movement) that are expected to be detected by the virtual second section sensor 105b after the leading edge of the virtual conveyed object a is detected by the virtual first section sensor 105a.

[0068] Because the rear limit line 21 is behind the virtual transported object a, the number of motor pulses required for the rear limit line 21 to reach the virtual second section sensor 105b is greater than the number of motor pulses required for the rear end of the virtual transported object a to reach the virtual second section sensor 105b. The number of motor pulses (amount of conveying movement) required from the time when it is assumed that the leading edge of the virtual transported object a is detected by the virtual first section sensor 105a until it is assumed that the rear limit line 21 is detected by the virtual second section sensor 105b is the maximum value of the assumed range (allowable range) of motor pulses (amount of conveying movement) expected from the time when the leading edge of the actual transported object a is detected by the real first section sensor 5a and until the rear end of the same actual transported object a is detected by the real second section sensor 5b when the actual transported object a moves normally.

[0069] In this embodiment, the trailing end side predicted conveying operation amount determining means 37 determines the roller motor pulses required from when the leading edge of the virtual conveyed article a is detected by the virtual first section sensor 105a until the rear limit line 21 is detected by the virtual second section sensor 105b. That is, in this embodiment, it is assumed that the conveyed article a moves normally, and the trailing end side predicted conveying operation amount determining means 37 determines the maximum (allowable value) of motor pulses (conveying operation amount) that are expected from when the leading edge of the actual conveyed article a is detected by the first section sensor 5a until the trailing end of the actual conveyed article a is detected by the second section sensor 5b.

[0070] Hereinafter, the maximum value (allowable value) of the motor pulses (amount of conveying movement) that are expected to occur when the rear end of the actual conveyed object a is detected by the second section sensor 5b after the leading edge of the actual conveyed object a determined by the rear end side expected conveying movement amount determining means 37 is detected by the first section sensor 5a will be referred to as the "expected rear end arrival pulse." The expected rear end arrival pulse is the expected rear end side conveying movement amount, which is the maximum amount of conveying movement that is expected to occur when the rear end of the conveyed object a is detected by the second section sensor 5b in the event of normal movement. The expected rear end arrival pulse is determined by calculation and is not actual. Based on the history of the expected rear end arrival pulse, the expected rear end arrival pulse is the maximum value of the motor pulses (amount of conveying movement) that are expected to occur when the rear end of the virtual conveyed object a is detected by the virtual second section sensor 105b after the leading edge of the virtual conveyed object a is detected by the virtual first section sensor 105a.

[0071] The conveying state estimation means 12 determines the accumulated value of motor pulses required for the virtual second section sensor 105b to detect the front end of the virtual conveyed item a and the accumulated value of motor pulses required for the virtual second section sensor 105b to detect the rear end of the virtual conveyed item a based on the front end side expected conveying operation amount determination means 36 and the rear end side expected conveying operation amount determination means 37.

[0072] Next, the driving status detection means 13 will be described. The driving status detection means 13 obtains information related to the actual driving status of the actual conveying device 2. Specifically, the driving status detection means 13 integrates pulses corresponding to the rotation of the motor output from the individual control device 7 using the actual pulse integration means 42. In this embodiment, the driving status detection means 13 detects the operation timing of the section sensor 5 under the actual driving status of the actual conveying device 2.

[0073] In this embodiment, the drive status detection means 13 integrates the actual motor pulses required from when the leading edge of the actually conveyed object a is detected by the first section sensor 5a until the leading edge of the actually conveyed object a is detected by the second section sensor 5b. Hereinafter, the actual motor pulses required from when the leading edge of the actually conveyed object a is detected by the first section sensor 5a until the leading edge of the actually conveyed object a is detected by the second section sensor 5b will be referred to as the actual leading edge arrival pulses. In this embodiment, the drive status detection means 13 also integrates the actual motor pulses required from when the leading edge of the actually conveyed object a is detected by the first section sensor 5a until the trailing edge of the actually conveyed object a is detected by the second section sensor 5b. Hereinafter, the actual motor pulses required from when the leading edge of the actually conveyed object a is detected by the first section sensor 5a until the trailing edge of the actually conveyed object a is detected by the second section sensor 5b will be referred to as the actual trailing edge arrival pulses.

[0074] The comparison means 28 includes a leading end comparison means 53 and a trailing end comparison means 55. The comparison means 28 compares the estimated transport status of the transported object estimated by the transport state estimation means 12 with the actual transport status of the transported object detected by the section sensor 5. In this embodiment, the comparison means 28 compares the leading end arrival actual pulse and the trailing end arrival actual pulse detected by the drive status detection means 13 with the leading end arrival estimated pulse (leading end side estimated transport operation amount) and the trailing end arrival estimated pulse (trailing end side estimated transport operation amount) determined by the leading end side estimated transport operation amount determination means 36 and the trailing end side estimated transport operation amount determination means 37. That is, the leading end comparison means 53 compares the leading end arrival actual pulse with the leading end arrival estimated pulse (leading end side estimated transport operation amount). Furthermore, the trailing end comparison means 55 compares the trailing end arrival actual pulse with the trailing end arrival estimated pulse (trailing end side estimated transport operation amount). If the measured pulses at the leading edge and the measured pulses at the trailing edge are within the range of the estimated pulses at the leading edge (estimated transport operation amount on the leading edge side) and the estimated pulses at the trailing edge (estimated transport operation amount on the trailing edge side), it is judged to be normal, and if they are outside the range, it is judged to be abnormal.

[0075] The transported object length measuring means 18 is a computer program that measures the total length of the transported object at the start of transport based on a signal from the first section sensor 5a. The transported object is placed in the preparation area 50 of the main transport path 10, moves along the main transport path 10, and enters the transport area 51. At this time, the transported object passes in front of the first section sensor 5a. When the leading edge of the transported object reaches the first section sensor 5a, the first section sensor 5a detects this. In other words, the first section sensor 5a turns on. While the transported object passes in front of the first section sensor 5a, the first section sensor 5a remains on. Then, once the transported object has finished passing in front of the first section sensor 5a, the first section sensor 5a turns off. The transported object length measuring means 18 calculates the total length of the transported object from the transport distance and time on the main transport path 10 while the first section sensor 5a is on.

[0076] The following describes the operation of the conveying system 1 of this embodiment. In the conveying system 1 of this embodiment, prior to actual conveying, a simulation of conveying a virtual conveying object a, etc., by the virtual conveying device 102 in the virtual space is performed, and the conveying status of the object a, etc., by the real conveying device 2 is compared.

[0077] The actual conveyed objects are randomly placed in the preparation area 50 of the conveyor line 25. For example, as shown in FIG. 2, actual conveyed objects a, b, and c are placed in the preparation area 50 of the conveyor line 25. The actual conveyed objects a, b, and c proceed downstream along the conveyor line 25, and the information reading means 8 reads the information from the codes attached to the objects. The read information is sent to the central control device 3. The central control device 3 searches for the corresponding objects in the object information storage means 30, and the destinations of each actual conveyed object a, b, and c are identified. In the conveying system 1 of this embodiment, the conveying order and destinations of the objects a, b, and c correspond to each other. Furthermore, when the objects enter the main conveying path 10 from the preparation area 50, the total length of the objects is calculated by the object length measuring means 18. Furthermore, if the information reading means 8 is provided with a measurement sensor (not shown) that measures the length of the objects, as illustrated as a modified example, the total length of each actual conveyed object a, b, and c is measured by the information reading means 8, and the length information is also sent to the central control device 3.

[0078] In this embodiment, the simulation of the virtual conveying device 102 begins after each actual conveyed item a, b, c passes through the first section sensor 5a and the total length of the conveyed item is calculated by the conveyed item length measuring means 18, or immediately after it passes through the information reading means 8.

[0079] For example, assume that actual transported object a is to be sent out onto branch conveying path A, and actual transported object b is to be sent out onto branch conveying path B. In the simulation, the first transported object is recognized as object a, the next transported object is recognized as object b, and the last transported object is recognized as object c. Then, the distance that each actual transported object a, b, and c must travel before reaching a predetermined branch point is converted into pulses. In the virtual transport device 102, when each actual transported object a, b, and c has traveled the calculated distance, it enters the target branch conveying path A or B.

[0080] Next, the operation of the actual conveying device 2 will be described. Actual conveyed objects a, b, and c of the actual conveying device 2 flow through the preparation area 50 and enter the conveying area 51. A signal is sent from the central control device 3 to the actual conveying device 2 so that it operates as simulated. Based on the signal from the actual conveying device 2, the central control device 3 calculates the actual travel distance of the actual conveyed objects a, b, and c after they pass the first section sensor 5. Specifically, the actual pulse accumulating means 42 accumulates pulses corresponding to the number of rotations of the motor (not shown) output from the conveying module 6 when the actual conveyed objects a, b, and c move, and calculates the actual travel distance of the actual conveyed objects a, b, and c after they pass the first section sensor 5.

[0081] For example, assume that the branch point of branch conveying path A is at a position of 2200 pulses, and the branch point of branch conveying path B is at a position of 3200 pulses, when the distance converted into pulses is 2200 pulses. When the travel distance of the article reaches the position of conveying module 6 corresponding to the branching position, a signal is sent from central control device 3 to conveying module 6 corresponding to actual conveying device 2, and a conveying direction changing device (not shown) attached to conveying module 6 is driven to send conveyed articles a, b, and c to the corresponding branch conveying paths A and B.

[0082] As described above, in the conveying system 1 of this embodiment, the conveying order of the conveyed objects corresponds to the conveying destination. The conveying system 1 of this embodiment recognizes only the order in which the actual conveyed objects a, b, and c are arranged, and sends them to branch conveying path A regardless of the identity of the first conveyed object. It also sends them to branch conveying path B regardless of the identity of the next conveyed object. The actual conveyed objects a, b, and c are arranged in the order a, b, and c as shown in FIG. 2. The actual conveyed objects a, b, and c are conveyed in this order. Information regarding the conveying destinations of the actual conveyed objects a, b, and c is transmitted from the central control device 3 to each conveying module 6. Regardless of the identity of the first conveyed object, when the travel distance of the first conveyed object reaches branch conveying path A, the first conveyed object enters branch conveying path A as shown in FIGS. 3 and 4. Regardless of the identity of the next conveyed object, when the travel distance of the first conveyed object reaches branch conveying path B, the first conveyed object enters branch conveying path B as shown in FIG. 5.

[0083] In this embodiment, the movement of the virtual conveying device 102 is compared with the movement of the actual conveying device 2, and if a large difference occurs between the two, a predetermined measure is taken. In the conveying system 1 of this embodiment, in particular, the comparison means 28 compares the estimated conveying status of the virtual conveyed object a, etc. estimated by the conveying status estimation means 12 with the actual conveying status of the actual conveyed object a, etc. detected by the section sensor 5. This operation will be described below.

[0084] In the conveying system of this embodiment, the conveying status of the actual conveyed item a from the first section sensor 5a to the second section sensor 5b is compared by the comparison means 28 with the assumed conveying status of the virtual conveyed item a, etc. assumed by the conveying state assumption means 12 and the actual conveying status of the actual conveyed item a, etc. detected by the section sensor 5. That is, when the leading end of the actual conveyed item a is detected by the first section sensor 5a of the actual conveying device 2, the assumed conveying status of the virtual conveyed item a of the virtual conveying device 102 is compared with the conveying status of the actual conveyed item a until the trailing end of the actual conveyed item a is detected by the second section sensor 5b. 8 to 14, when the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, the leading edge of the actual transported object a passes through the first section sensor 5a, and the rear end of the actual transported object a passes through the first section sensor 5a and the total length of the actual transported object a is measured, a presence area 15 is defined around the virtual transported object a of the virtual transport device 102, and a front limit line 20 and a rear limit line 21 are determined. The size of the presence area 15 varies depending on the size of the actual transported object a. In other words, the length of the transported object a is measured by the first section sensor 5a or the information reading means 8, and the size of the presence area 15 varies depending on the measured total length of the actual transported object a.

[0085] In this embodiment, the detection state of the second section sensor 5b when the actual transported object a passes through the second section sensor 5b is compared with the detection state when the virtual transported object a of the virtual transport device 102 passes through the virtual second section sensor 105b. That is, if the presence area 15 of the virtual transport device 102 in the virtual space passes through the virtual second section sensor 105b at the same time that the actual transported object a passes through the second section sensor 5b, it is determined that the passage is normal. If there is a difference between the timing at which the actual transported object a passes through the second section sensor 5b and the timing at which the presence area 15 of the virtual transport device 102 passes through the virtual second section sensor 105b, and the actual transported object a is unable to pass through the second section sensor 5b while the presence area 15 of the virtual transport device 102 passes through the virtual second section sensor 105b, it is determined that the passage is abnormal.

[0086] More specifically, when the leading edge of the actual transported object a is detected by the second section sensor 5b, if the front limit line 20 of the virtual transported object a has not reached the virtual second section sensor 105b, it is determined that the object has passed abnormally. Similarly, when the trailing edge of the actual transported object a is detected by the second section sensor 5b, if the rear limit line 21 of the virtual transported object a has already passed the virtual second section sensor 105b, it is determined that the object has passed abnormally.

[0087] In practice, the actual conveying movement amount of the actual conveying device 2 when the actually conveyed article a moves from the position of the first section sensor 5a to the position of the second section sensor 5b is detected by the drive status detection means 13 by integrating the motor pulses, and this motor pulse is compared with the motor pulses determined by the leading end side expected conveying movement amount determination means 36 and the motor pulses determined by the trailing end side expected conveying movement amount determination means 37. In other words, the motor pulses corresponding to the actual conveying movement amount from when the leading end of the actually conveyed article a is detected by the first section sensor 5a until the leading end of the actually conveyed article a is detected by the second section sensor 5b are compared with the motor pulses corresponding to the conveying movement amount required for the front limit line 20 to be detected by the virtual second section sensor 105b. In addition, the motor pulses corresponding to the actual conveying movement amount from when the leading edge of the actual conveyed item a is detected by the first section sensor 5a until the rear end of the actual conveyed item a is detected by the second section sensor 5b are compared with the motor pulses corresponding to the conveying movement amount required for the rear limit line 21 to be detected by the virtual second section sensor 105b.

[0088] FIG. 8 shows a situation in which an actual transported object a passes through the relevant section as determined by the transport state estimation means 12. That is, as shown in FIG. 8( a), when the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, a virtual transported object a also appears on the virtual transport device 102 side. Note that the virtual transported object a at this stage is merely a model and has little practical significance. Therefore, the appearance of the virtual transported object a on the virtual transport device 102 side may occur after the trailing edge of the actual transported object a passes in front of the first section sensor 5a of the actual transport device 2. Then, as shown in FIG. 8( b), the virtual transported object a on the virtual transport device 102 and the actual transported object a on the actual transport device 2 both move forward. When the virtual transported object a leaves the virtual first section sensor 105a, an existence area 15 is defined around the virtual transported object a on the virtual transport device 102 as described above, and a front limit line 20 and a rear limit line 21 are determined. 8(c), the virtual transported object a of the virtual transport device 102 and the real transported object a of the real transport device 2 move forward at the same speed. As shown in FIGS. 8(d) and 8(e), the virtual transported object a of the virtual transport device 102 and the real transported object a of the real transport device 2 pass through the second section sensors 5b and 105b at the same time.

[0089] Figure 9 shows a situation in which an actual transported object a passes through the relevant section slightly faster than the transport state determined by the transport state estimation means 12. However, in the example shown in Figure 9, the presence area 15 of the virtual transport device 102 passes through the virtual second section sensor 105b at the same time that the actual transported object a passes through the second section sensor 5b, which is normal passage. That is, as shown in Figure 9(a), when the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, the virtual transported object a also appears on the virtual transport device 102 side. As shown in Figure 9(b), the progress of the actual transported object a is faster than the progress of the virtual transported object a. The difference between the two gradually widens as shown in Figure 9(c), but as shown in Figure 9(d), when the leading edge of the actual transported object a on the actual transport device 2 reaches the second section sensor 5b, at least the front limit line 20 of the virtual transport device 102 has reached the virtual second section sensor 105b.

[0090] 9(e), when the rear end of the actual transported object a of the real transport device 2 reaches the second section sensor 5b, the rear limit line 21 of the virtual transport device 102 has not reached the virtual second section sensor 105b. Therefore, in the transport situation in FIG. 9, the actual transported object a is proceeding slightly faster than the transport state determined by the transport state estimating means 12, but is within the range of normal passage.

[0091] That is, when the leading edge of the actual conveyed object a of the actual conveying device 2 reaches the second section sensor 5b, the leading edge comparison means 53 compares the actual conveying operation amount with the leading edge arrival estimated pulse (leading edge side estimated conveying operation amount). The leading edge arrival estimated pulse is the minimum value (allowable value) of the motor pulse (conveying operation amount) that is estimated when the leading edge of the actual conveyed object a is detected by the first section sensor 5a and then detected by the second section sensor 5b. In the conveying situation shown in FIG. 9 , the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 as it moves from the leading edge of the actual conveyed object a is detected by the first section sensor 5a until the leading edge of the actual conveyed object a is detected by the second section sensor 5b is greater than the leading edge side estimated conveying operation amount determined by the leading edge side estimated conveying operation amount determination means 36. Therefore, in the conveying situation shown in FIG. 9 , the actual conveyed object a is proceeding slightly faster than the conveying state determined by the conveying state estimation means 12, but the leading edge of the actual conveyed object a is passing normally.

[0092] Furthermore, when the rear end of the actual conveyed object a of the actual conveying device 2 reaches the second section sensor 5b, the rear end comparison means 55 compares the actual conveying operation amount with the rear end arrival expected pulse (rear end side expected conveying operation amount). The rear end arrival expected pulse is the maximum value (allowable value) of motor pulses (conveying operation amount) that are expected to be detected by the second section sensor 5b after the leading end of the actual conveyed object a is detected by the first section sensor 5a. In the conveying situation of Figure 9, the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 when moving from the leading end of the actual conveyed object a is detected by the first section sensor 5a until the trailing end of the actual conveyed object a is detected by the second section sensor 5b is less than the rear end arrival expected pulse (rear end side expected conveying operation amount) determined by the rear end side expected conveying operation amount determination means 37. Therefore, in the conveying state shown in FIG. 9, the actual conveyed article a is proceeding slightly faster than the conveying state determined by the conveying state estimating means 12, but the rear end of the actual conveyed article a passes through normally.

[0093] When the rear end of the actual transported object a passes the second section sensor 5b, the reset means 16 resets the relationship between the virtual transport device 102 and the actual transport device 2 within that section. That is, within that section, the actual transported object a is moving faster than the transport state determined by the transport state estimating means 12, and there is a deviation between the position of the actual transported object a and the position of the virtual transported object a, but when the rear end of the actual transported object a passes the second section sensor 5b, the deviation between the two is reset, and a new virtual transported object a appears on the virtual transport device 102 side. The new virtual transported object a has the existence area 15 described above.

[0094] In the above explanation, the deviation between the two is reset when the rear end of the actual transported object a passes the second section sensor 5b, but the timing at which the reset means 16 resets the relationship between the virtual transport device 102 and the actual transport device 2 may also be when the front end of the actual transported object a passes the second section sensor 5b. In other words, since the total length of the actual transported object a is known, the deviation between the two may be reset when the front end of the actual transported object a passes the second section sensor 5b, and a new virtual transported object a may appear on the virtual transport device 102 side.

[0095] Figure 10 shows a situation in which the actual transported object a passes through the relevant section while proceeding slower than the transport state determined by the transport state estimating means 12. However, in the example shown in Figure 10, the presence area 15 of the virtual transport device 102 passes through the virtual second zone sensor 105b at the same time that the actual transported object a passes through the second zone sensor 5b, which is a normal passage.

[0096] That is, as shown in Figure 10(a), when the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, the virtual transported object a also appears on the virtual transport device 102 side. As shown in Figure 10(b), the progress of the actual transported object a is slower than the progress of the virtual transported object a. The difference between the two gradually widens as shown in Figures 10(c) and 10(d). However, as shown in Figure 10(e), when the leading edge of the actual transported object a of the actual transport device 2 reaches the second section sensor 5b, at least the front limit line 20 of the virtual transport device 102 has reached the virtual second section sensor 105b. Also, as shown in Figure 10(f), when the trailing edge of the actual transported object a of the actual transport device 2 reaches the second section sensor 5b, the rear limit line 21 of the virtual transport device 102 has not yet reached the virtual second section sensor 105b. Therefore, in the conveying state shown in FIG. 10, the actual conveyed object a is proceeding slightly slower than the conveying state determined by the conveying state estimating means 12, but is within the range of normal passage.

[0097] That is, when the leading edge of the actual conveyed object a of the actual conveying device 2 reaches the second section sensor 5b, the leading edge comparison means 53 compares the actual conveying operation amount with the leading edge arrival assumed pulse (leading edge side predicted conveying operation amount). Also, when the trailing edge of the actual conveyed object a of the actual conveying device 2 reaches the second section sensor 5b, the trailing edge comparison means 55 compares the actual conveying operation amount with the trailing edge arrival assumed pulse (trailing edge side predicted conveying operation amount). In the conveying situation of FIG. 10 , the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 as it moves from when the leading edge of the actual conveyed object a is detected by the first section sensor 5a until the leading edge of the actual conveyed object a is detected by the second section sensor 5b is greater than the leading edge side predicted conveying operation amount determined by the leading edge side predicted conveying operation amount determination means 36. Therefore, in the conveying situation of FIG. 10 , the leading edge of the conveyed object a passes normally.

[0098] 10, the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 when the actual conveyed article a moves from when its leading edge is detected by the first section sensor 5a until its trailing edge is detected by the second section sensor 5b is less than the trailing edge arrival estimated pulses (trailing edge side estimated conveying operation amount) determined by the trailing edge side estimated conveying operation amount determining means 37. Therefore, in the conveying situation in FIG. 10, the trailing edge of the actual conveyed article a passes normally.

[0099] When the rear end of the actual transported object a passes the second section sensor 5b, the reset means 16 resets the relationship between the virtual transport device 102 and the actual transport device 2 within that section. That is, within that section, the actual transported object a is proceeding slower than the transport state determined by the transport state estimation means 12, and there is a deviation between the position of the actual transported object a and the position of the virtual transported object a. However, when the rear end of the actual transported object a passes the second section sensor 5b, the deviation between the two is eliminated, and a new virtual transported object a appears on the virtual transport device 102 side. The new virtual transported object a has the above-mentioned existence area 15. As described above, when the front end of the actual transported object a passes the second section sensor 5b, the deviation between the two may be reset, and a new virtual transported object a may appear on the virtual transport device 102 side.

[0100] FIG. 11 illustrates a situation in which an actual transported object a passes through the relevant section at a speed significantly faster than the transport state determined by the transport state estimation means 12. In the example shown in FIG. 11, when the actual transported object a reaches the second section sensor 5b, the presence area 15 of the virtual transport device 102 has not yet reached the virtual second section sensor 105b, resulting in an abnormal passage. That is, as shown in FIG. 11(a), when the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, the virtual transported object a also appears on the virtual transport device 102 side. As shown in FIG. 11(b), the progress of the actual transported object a is significantly faster than the progress of the virtual transported object a. The difference between the two then widens as shown in FIGS. 11(c) and 11(d), and as shown in FIG. 11(e), when the leading edge of the actual transported object a on the actual transport device 2 reaches the second section sensor 5b, the front limit line 20 of the virtual transport device 102 has not yet reached the virtual second section sensor 105b. Therefore, in the conveying situation in FIG. 11, the actual conveyed article a is proceeding faster than the conveying state determined by the conveying state estimating means 12, and is passing abnormally.

[0101] That is, when the leading end of the actual conveyed article a of the actual conveying device 2 reaches the second section sensor 5b, the leading end comparison means 53 compares the actual conveying operation amount with the leading end arrival estimated pulse (leading end side estimated conveying operation amount). In the conveying situation of Figure 11, the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 when moving from when the leading end of the actual conveyed article a is detected by the first section sensor 5a until when the leading end of the actual conveyed article a is detected by the second section sensor 5b is less than the leading end side estimated conveying operation amount determined by the leading end side estimated conveying operation amount determination means 36. Therefore, in the conveying situation of Figure 11, the leading end of the conveyed article a does not pass normally.

[0102] FIG. 12 illustrates a situation in which an actual transported object a passes through the relevant section at a significantly slower rate than the transport state determined by the transport state estimation means 12. In the example shown in FIG. 12, when the rear end of the actual transported object a passes the second section sensor 5b, the presence area 15 of the virtual transport device 102 passes the virtual second section sensor 105b, resulting in an abnormal passage. That is, as shown in FIG. 12(a), when the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, the virtual transported object a also appears on the virtual transport device 102 side. As shown in FIG. 12(b), the progress of the actual transported object a is significantly slower than the progress of the virtual transported object a. The difference between the two then widens as shown in FIGS. 12(c) and 12(d), and as shown in FIG. 12(e), when the rear end of the actual transported object a on the actual transport device 2 reaches the second section sensor 5b, the rear limit line 21 of the virtual transport device 102 has already passed the virtual second section sensor 105b. Therefore, in the conveying state of FIG. 12, the actual conveyed object a passes through abnormally, slower than the conveying state determined by the conveying state estimating means 12.

[0103] That is, when the rear end of the actual conveyed article a of the actual conveying device 2 reaches the second section sensor 5b, the rear end comparison means 55 compares the actual conveying operation amount with the rear end arrival expected pulse (rear end side expected conveying operation amount). In the conveying situation of Figure 12, the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 when moving from when the front end of the actual conveyed article a is detected by the first section sensor 5a until the rear end of the actual conveyed article a is detected by the second section sensor 5b is greater than the front end side expected conveying operation amount determined by the rear end side expected conveying operation amount determination means 37. Therefore, in the conveying situation of Figure 12, the rear end of the actual conveyed article a does not pass normally.

[0104] Figure 13 shows a situation in which an object a is removed between the first section sensor 5a and the second section sensor 5b. That is, as shown in Figure 13(a), when the leading edge of the actual object a is detected by the first section sensor 5a of the actual conveying device 2, a virtual object a also appears on the virtual conveying device 102 side. As shown in Figure 13(b), the actual object a progresses at the same speed as the virtual object a. Also, in Figure 13(b), the leading edge of the actual object b is detected by the first section sensor 5a of the actual conveying device 2, and a virtual object b also appears on the virtual conveying device 102 side. Then, as shown in Figure 13(c), the actual object a progresses at the same speed as the virtual object a, and the actual object b also progresses at the same speed as the virtual object b. Finally, at the stage shown in Figure 13(d), the leading actual object a is removed. Therefore, the following actual object b essentially moves ahead. However, the virtual transported object a does not disappear on the virtual transport device 102, and the virtual transported object a continues to move forward. Then, as shown in Figure 13(e), when the currently leading transported object b reaches the second division sensor 5b, the presence area 15 of the leading virtual transported object a on the virtual transport device 102 has already passed the virtual second division sensor 105b.

[0105] That is, when the rear end of the actual conveyed object b of the actual conveying device 2 reaches the second section sensor 5b, the rear end comparison means 55 compares the actual conveying operation amount with the expected rear end arrival pulse (expected rear end conveying operation amount). In the conveying situation of Figure 13, the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 when moving from when the front end of the actual conveyed object a is detected by the first section sensor 5a until the rear end of the actual conveyed object b is detected by the second section sensor 5b is greater than the expected rear end conveying operation amount determined by the expected rear end conveying operation amount determination means 37. Therefore, in the conveying situation of Figure 13, the rear end of the actual conveyed object a is not passing normally. Therefore, if the conveyed object is removed, it can be determined that the passage is abnormal.

[0106] FIG. 14 shows a situation where an unexpected transported object x is inserted between the first section sensor 5a and the second section sensor 5b. That is, as shown in FIG. 14(a), when the leading edge of the actual transported object a is detected by the first section sensor 5a of the real transport device 2, a virtual transported object a also appears on the virtual transport device 102 side. As shown in FIGS. 14(b) and 14(c), the actual transported object a is traveling at the same speed as the virtual transported object a. Then, at the stage shown in FIG. 14(d), the actual transported object x is inserted in front of the leading actual transported object a. Therefore, the actually inserted actual transported object x moves forward at the front. However, on the virtual transport device 102, the virtual transported object x does not appear, and the virtual transported object a continues to move forward. Then, as shown in FIG. 14(e), when the actual transported object x currently moving forward at the front reaches the second section sensor 5b, the presence area 15 of the leading virtual transported object a on the virtual transport device 102 has not yet reached the virtual second section sensor 105b.

[0107] That is, when the leading edge of the actual conveyed object x of the actual conveying device 2 reaches the second section sensor 5b, the leading edge comparison means 53 compares the actual conveying operation amount with the leading edge arrival estimated pulse (leading edge side estimated conveying operation amount). In the conveying situation of Figure 14, the actual conveying operation amount (integrated value of motor pulses) of the actual conveying device 2 as it moves from when the leading edge of the actual conveyed object a is detected by the first section sensor 5a until the leading edge of the actual conveyed object x is detected by the second section sensor 5b is less than the leading edge side estimated conveying operation amount determined by the leading edge side estimated conveying operation amount determination means 36. Therefore, in the conveying situation of Figure 14, the leading edge of the conveyed object a does not pass normally. Therefore, if an unexpected conveyed object x is introduced, it can be determined that the passage is abnormal.

[0108] If the passage of the transported object a is abnormal, the following measures are taken, for example: (1) Change the transport speed of the transport device; (2) Correct the estimated transport status of the transport status estimation means; (3) Change the destination of the transported object; (4) Stop the transport device; (5) Report

[0109] "Changing the conveying speed of the conveying device" may involve changing the speed of the entire conveying device, or changing the speed of a certain section of the conveying device. "Correction of the estimated conveying status of the conveying status estimation means" is a measure taken when it is deemed that the estimated conveying status is unrealistic, and changes the setting of the estimated conveying status. "Changing the destination of the conveyed item" involves, for example, returning the conveyed item to its initial position. Alternatively, for example, changing the destination to the manual work area 27 so that it can be sorted manually by a worker. "Stopping the conveying device" may involve stopping the entire conveying device 2, or stopping a certain section of the conveying device 2. "Changing the conveying route" involves detouring the conveyed item to its specified destination. "Alert" involves, for example, displaying warning text or light on the display device 17, or playing a sound from the speaker.

[0110] In the above-described embodiment, for ease of understanding, the virtual conveying device 102 and the actual conveying device 2 are described as operating simultaneously, but the virtual conveying device 102 and the actual conveying device 2 do not need to operate simultaneously. In short, when the actual conveyed object a is detected by the section sensor 5, the actual conveying operation amount is compared with the leading edge arrival estimated pulse (leading edge side estimated conveying operation amount) and the trailing edge arrival estimated pulse (trailing edge side estimated conveying operation amount).

[0111] In the embodiment described above, the comparison means 28 compares the estimated transport state of the transported object estimated by the transport state estimation means 12 with the actual transport state of the transported object detected by the sensor 5. That is, in the above embodiment, an estimated transport state of the transported object is established and compared with the actual movement of the transported object. However, without estimating the estimated transport state of the transported object, a comparison may be made simply between a leading-end estimated transport movement amount, which is the minimum amount of transport movement expected when the leading end of the transported object is detected by a sensor at a predetermined position if the transported object moves normally, and the actual transport movement amount when the leading end of the transported object is actually detected by a sensor at a predetermined position. Similarly, a comparison may be made simply between a trailing-end estimated transport movement amount, which is the maximum amount of transport movement expected when the trailing end of the transported object is detected by a sensor at a predetermined position if the transported object moves normally, and the actual transport movement amount when the trailing end of the transported object is actually detected by a sensor at a predetermined position.

[0112] In the embodiment described above, as shown in each of (b) of Figures 8 to 14, when the virtual transported object a leaves the virtual first section sensor 105a, a presence area 15 is defined around the virtual transported object a on the virtual transport device 102, and a front limit line 20 and a rear limit line 21 are determined. However, the present invention is not limited to this configuration. When the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2, the virtual transported object a may also appear on the virtual transport device 102 side, and the presence area 15 may be defined at the same time. Alternatively, the presence area 15 may be defined while the leading edge of the actual transported object a is detected by the first section sensor 5a of the actual transport device 2. In other words, any means may be used to detect the total length of the actual transported object a. If the total length of the actual transported object a is known at the time the leading edge of the transported object a is detected by the first section sensor 5a of the actual transport device 2, the presence area 15 may be defined at an early stage.

[0113] In the embodiment described above, the estimated leading edge arrival pulse is the minimum value (tolerance) of the motor pulses (transport operation amount) at which the leading edge of the actually conveyed object a is expected to be detected by the second section sensor 5b, and does not have a range. That is, as described below, the estimated leading edge arrival pulse (estimated leading edge conveyance operation amount) is a numerical value, such as 1950 pulses, and does not have a range. That is, in the embodiment described above, only the front end (front limit line 20) of the existence area 15 is determined, and its range is not limited. The present invention is not limited to this configuration, and the estimated leading edge arrival pulse may have upper and lower limits. For example, the estimated leading edge arrival pulse may have upper and lower limits, such as 1950 pulses to 2000 pulses.

[0114] If the leading edge arrival assumed pulse has upper and lower limits, it is possible to detect earlier if the transported object a is removed between the first section sensor 5a and the second section sensor 5b, as shown in Figure 15. That is, in the embodiment shown in Figure 15, the leading edge arrival assumed pulse has an upper limit UL and a lower limit LL. In the embodiment shown in Figure 15, as shown in Figure 15(e), when the leading virtual transported object a on the virtual transport device 102 reaches the upper limit UL in the presence area 15, the currently leading transported object b has not yet reached the second section sensor 5b. Therefore, according to this embodiment, it is possible to detect that the actual transported object a has been removed when the leading virtual transported object a on the virtual transport device 102 reaches the upper limit UL in the presence area 15.

[0115] In addition, the above-described embodiment compares the expected amount of conveying movement (estimated pulse) in the event of normal movement with the actual amount of conveying movement (actual measured pulse), which is the actual amount of conveying movement of the conveying device. However, in addition to this, or instead of this, it is also possible to compare the expected passing time between sensors in the event of normal movement of the conveyed object with the actual time required for the conveyed object to pass between the sensors.

[0116] For example, the conveyance state estimating means 12 determines the time required from when the leading edge of the virtual conveyed object a is detected by the virtual first section sensor 105a until the leading edge of the virtual conveyed object a is detected by the virtual second section sensor 105b. The conveyance state estimating means also determines the time required from when the leading edge of the virtual conveyed object a is detected by the virtual first section sensor 105a until the trailing edge of the virtual conveyed object a is detected by the virtual second section sensor 105b. The drive status detecting means 13 integrates the time required from when the leading edge of the actual conveyed object a is detected by the first section sensor 5a until the leading edge of the actual conveyed object a is detected by the second section sensor 5b. The comparing means then compares the estimated required time with the actual required time.

[0117] 8 to 10, the passing times of the leading and trailing ends of the actual conveyed article a are within the range assumed by the conveyance state assuming means, which is the range of normal passing. In contrast, in the examples shown in Figures 11 to 14, the passing times of the leading or trailing ends of the actual conveyed article a are outside the range assumed by the conveyance state assuming means, which is the range of abnormal passing.

[0118] An example of the presence area 15, etc., will be described below with reference to FIG. 16. For example, as shown in FIG. 16(a), assume that the distance from the first section sensor 5a to the second section sensor 5b corresponds to D pulses, and the total length of the actual conveyed object a is M pulses. The presence area 15 is F pulses, which is greater than the total length of the actual conveyed object a, M pulses. For example, the front end of the presence area 15 (front limit line 20) is fg forward from the front end of the actual conveyed object a. The rear end of the presence area 15 (rear limit line 21) is rg rearward from the front end of the actual conveyed object a.

[0119] 16(b), the amount of conveyance movement from when the leading edge of the actual conveyed article a is at the position of the first section sensor 5a until the leading edge of the actual conveyed article a reaches the second section sensor 5b corresponds to pulse D. In other words, pulse D is the amount of conveyance movement when the actual conveyed article a proceeds normally without any obstacles.

[0120] In contrast, the presence area 15 is an allowable range in which the actual conveyed object a exists, and the front end of the presence area 15 (front limit line 20) indicates the allowable front end if the actual conveyed object a moves faster with an error within an expected range. Since the front limit line 20 is located fg forward from the front end of the actual conveyed object a, the amount of conveyance movement from when the leading edge of the actual conveyed object a is at the position of the first section sensor 5a until the leading edge of the front limit line 20 reaches the second section sensor 5b is "D-fg," as shown in FIG. 16(b). The amount of conveyance movement "D-fg" from when the leading edge of the actual conveyed object a is at the position of the first section sensor 5a until the leading edge of the front limit line 20 reaches the second section sensor 5b is the leading edge predicted conveyance movement amount, which is the minimum amount of conveyance movement expected for the leading edge of the conveyed object to be detected by a sensor at a predetermined position if the object moves normally.

[0121] The rear end of the presence area 15 (rear limit line 21) indicates the allowable rear end when the actual conveyed object a moves as slowly as possible within an expected range. Since the rear limit line 21 is located rg behind the rear end of the actual conveyed object a, the amount of conveying movement from when the leading edge of the actual conveyed object a is at the position of the first section sensor 5a until the rear limit line 21 reaches the second section sensor 5b is "D+M+rg." The amount of conveying movement "D+M+rg" from when the leading edge of the actual conveyed object a is at the position of the first section sensor 5a until the leading edge of the rear limit line 21 reaches the second section sensor 5b is the expected rear end conveying movement amount, which is the maximum amount of conveying movement that is expected to detect the rear end of the conveyed object by a sensor at a specified position when the object moves normally.

[0122] If the D pulses representing the transport movement amount until the leading end of the virtual transported object a reaches the virtual second section sensor 105b are 2000 pulses, the M pulses representing the total length of the actual transported object a are 300 pulses, and fg and rg are 30 pulses, the predicted transport movement amount on the leading end side is 1970 pulses. Also, the predicted transport movement amount on the trailing end side is 2330 pulses.

[0123] The conveying system 1 described above employs, for example, a transmissive optical sensor equipped with a pair of a light emitter and a light receiver as the section sensor 5 of the conveyor line 25. The section sensor 5 employed in the conveying system 1 is a single sensor that determines whether or not something is present between the light emitter and the light receiver. That is, the section sensor 5 employed in the conveying system 1 is composed of only one light emitter and one light receiver. The section sensor 5 employed in the conveying system 1 simply detects whether or not a transported object is present between the light emitter and the light receiver. On the other hand, the conveying system 151 of the second embodiment described below aims to realize a conveying system that can recognize the shape, size, orientation, etc. of a transported object when viewed from above. The conveying system 151 is a conveying system that can also recognize situations such as when transported objects are tilted, when transported objects are traveling side by side, or when a rear transported object is pushing a front transported object and transporting them as if they were a single object.

[0124] In the conveying system 151 of the second embodiment, a sensor group 112 is employed as the compartment sensor 5, which is configured by arranging a plurality of sensor elements 121 in parallel in a line perpendicular to the conveying direction at intervals as shown in FIG. 18 . The sensor group 112 is a unit formed by arranging a plurality of sensor elements 121 in series and housing them in a predetermined case 186. Hereinafter, the sensor group will be referred to as a sensor unit 112. In this embodiment, the sensor unit (sensor group) 112 is arranged so that the sensor elements 121 are perpendicular to the conveying direction of the conveyed object, as shown in FIG. 17 .

[0125] In the conveyor line 200 of the conveying system 151 of the second embodiment, as shown in FIG. 17 , the section sensor 5, which is composed of a single sensor and is employed in the conveyor line 25 of the previous embodiment, is replaced with sensor units 112 (112a-112e). That is, while the conveying system 1 of the first embodiment employed a single sensor as the section sensor 5, the conveying system 151 of the second embodiment employs a sensor unit (sensor group) 112 as the section sensor 5, in which multiple sensor elements 121 are arranged in series and housed in a predetermined case 186. The basic component configuration of the conveyor line 200 is the same as that of the conveyor line 25 of the conveying system 1 of the previous embodiment. That is, as shown in FIG. 17 , the conveyor line 200 includes a conveying device 2 consisting of a roller conveyor and multiple section sensors 5 (sensor units 112). The conveying device 2 is comprised of a number of well-known conveying modules 6 connected together, which are referred to as zone conveyors. The transport module 6 is provided with a load sensor 45 (FIG. 7).

[0126] The conveyor line 200 is similar to the previous embodiment and includes a single main conveying path 10 and multiple branch conveying paths A and B branching off from the main conveying path, as shown in FIG. 17 . Multiple section sensors 5 (sensor units 112) are installed at regular intervals on the conveyor line 200. For ease of explanation, let's assume that the sections of the conveying area 51 are a first section 70a, a second section 70b, a third section 70c, a fourth section 70d, and a fifth section 70e, as shown in FIG. 17 . The section sensors 5 (sensor units 112) are installed between the preparation area 50 and the first section 70a, and between each section. The section sensors 5 (sensor units 112) are each composed of multiple sensor members 121 arranged in a direction perpendicular to the conveying direction of the transported objects.

[0127] Like the central control device 3 described above, the central control device 153 of this embodiment also includes a CPU and memory, and stores programs for realizing desired functions. Major functional blocks include conveyor control means 11, transport state estimation means 162, drive status detection means 163, comparison means 158, reset means 16, and transported object length measurement means 18. In this embodiment, signals from the sensor unit 112, the information reading means 8, and each transport module 6 are input to the central control device 153, and the transport module 6 and display device 17 are connected to the output side of the information reading means 8.

[0128] The function of the conveyor control means 11 is the same as in the previous embodiment, and therefore a description thereof will be omitted. The function of the conveyance state estimation means 162 is to estimate the movement posture of the conveyed object during conveyance, in addition to the functions of the previous embodiment. That is, the conveyance state estimation means 162 employed in this embodiment, like the conveyance state estimation means 12 employed in the previous embodiment, estimates and determines the conveyance state of the conveyed object using a computer. Furthermore, the conveyance state estimation means 162 particularly functions as an estimated pulse calculation means 35 and a virtual conveyance object conveyance operation amount determination means 185. These functions are equivalent to those of the conveyance state estimation means 12 employed in the previous embodiment. The conveyance state estimation means 162 estimates the movement posture of the conveyed object during conveyance so that the conveyed object moves in a straight line.

[0129] Next, the driving condition detection means 163 will be described. The driving condition detection means 163 has the same functions as the driving condition detection means 13 employed in the previous embodiment, and in addition has a sensor image generation means 155 that generates a sensor image, and a detected conveyed object determination means 156. According to the driving condition detection means 163, the sensor image generation means 155 and the detected conveyed object determination means 156 can determine the shape / size / posture of the actual conveyed object (detected conveyed object detected by the sensor unit 112) in a planar view.

[0130] The central control device 153 has a comparison means 158. In this embodiment, the comparison means 158 compares the detected transported object determined by the detected transported object determination means 156 with the virtual transported object to determine whether or not an abnormality has occurred during the transport process. The detected transported object is a planar shape created by the sensor image generation means 155 based on the transport distance between the sensor unit 112 and the actual transported object, and reflects the shape, size, and posture of the actual transported object. By comparing the detected transported object with the virtual transported object, it is possible to detect, for example, whether the posture has tilted or whether transported objects are running side by side.

[0131] The resetting means 16 is the same as that in the previous embodiment, that is, the resetting means 16 resets the relationship between the virtual transport device 102 and the real transport device 2 in the section at a predetermined timing.

[0132] The operation of the transport system of the second embodiment will be described in more detail below. In the following description of the second embodiment, components having the same functions as those in the first embodiment are denoted by the same numbers as those in the first embodiment.

[0133] First, we will explain how the central control device 153 of the conveying system 151 of the second embodiment detects the driving conditions, such as the conveying posture of the conveyed object and whether or not the objects are traveling in parallel. With reference to Figures 21 and 22, we will explain the operation when the conveyed object is conveyed from the first section 70a to the second section 70b in a posture parallel to the conveying direction. As shown in Figure 17, both the first section 70a and the second section 70b have a considerable length, with multiple conveying modules 6 connected in series. However, for ease of illustration, only the boundary between the first section 70a and the second section 70b is shown in Figures 21 and 22.

[0134] Many of the drawings from Figure 21 onwards are drawn in four rows. From the top row, the rows are labeled with letters (a), (b), (c), and (d) and are numbered with suffixes such as 1, 2, 3, etc. In each figure, the top row labeled (a) is a diagram showing the movement of an actual transported object on the transport device. The second row labeled (b) is a diagram showing the sensor image on the transport device. The third row labeled (c) is a diagram showing the shape and form of the transported object derived from the sensor image at the time of reset. The fourth row labeled (d) is a diagram showing the movement of a virtual transported object on the transport device.

[0135] The numbers 1, 2, 3, etc. indicate changes over time. For example, in the top diagrams labeled (a), the actual transported object is initially at position (a1), and as time passes, the actual transported object moves to its position (a2), (a3), (a4), etc. The same is true for the second diagram labeled (b), the third diagram labeled (c), and the fourth diagram labeled (d), which also show changes over time.

[0136] As shown in Figures 17, 21, and 22, a second sensor unit 112b is disposed at the tip of the second section 70b. In this embodiment, each of the second sensor units 112b has eight sensor elements 121 arranged in a line. The number of sensor elements 121 included in the sensor units 112a, 112b, 112c, 112d, and 112e is not limited to eight. It may be more or less than eight. The sensor unit 112b may be configured by arranging multiple sensor elements 121 in parallel in a line with a gap between them. In Figures 21 and 22, only the symbols (a1) to (a4) indicating the movement of the actual conveyed object a are indicated.

[0137] The sensor member 121 is a sensor capable of detecting the presence of an object, and in this embodiment, a reflective photoelectric sensor is used. That is, the sensor member 121 has a light-emitting section and a light-receiving section within a single housing, and detects the presence of the object at a predetermined location when light emitted from the light-emitting section is reflected by the object to be detected and reaches the light-receiving section. That is, the sensor member 121 performs a detection operation to detect the presence or absence of the object at a predetermined location without contact. Although not particularly limited, in this embodiment, a photodiode is used as the sensor element constituting the light-receiving section.

[0138] The actual transported object a moves from left to right as shown in Figures 21(a1), (a2), 22(a3), and (a4). In Figure 21(a1), the actual transported object a is in the first section 70a and then moves to Figure 22(a4). To make the detection operation of the sensor unit 112 easier to understand, the following description will be given assuming that the virtual transported object on the transport device is initialized only when the actual transported object passes through the sensor unit 112b.

[0139] The actual conveyed object a passes through the second sensor unit 112b and proceeds to the second section 70b. At this time, when the actual conveyed object a begins to pass over the second sensor unit 112b, reflected light reaches the light receiving portion of the sensor element 121, and as shown in FIG. 21(b2), the drive status detection means 163 of the central control device 153 begins to form a sensor image sa using the sensor image generation means 155. That is, the actual conveyed object a is moved at a constant speed, and the on / off state of each sensor element 121 of the lower sensor unit 112b is monitored during this movement. Because each sensor element 121 of the sensor unit 112b is arranged in a straight line, the presence or absence of an object on the sensor unit 112b is detected instantaneously, and this is detected as a line. As the actual conveyed object a moves over time, the line indicating the presence or absence of an object on the sensor unit 112b at each instant spreads out into a plane, forming a figure with an area.

[0140] That is, by accumulating the images (lines) of the actual transported object a captured by the sensor unit 112b on the time axis, the sensor image sa is formed as shown in Figures 21(b1), (b2), 22(b3), and (b4). That is, by accumulating the images of the actual transported object a captured by the sensor unit 112b on the time axis, the sensor image sa is formed as shown in Figures 21(b1), (b2), 22(b3), and (b4). The sensor unit operation time of the second sensor unit 112b is associated with the transport operation amount (number of motor pulses) by the actual pulse accumulating means 42. This makes it possible to compare the relative positional relationship with the virtual transported object ia, which is expressed in terms of the number of motor pulses, as will be described later.

[0141] Accumulation of the sensor image sa begins when the leading edge of the transported object a passes over the sensor unit 112 located upstream of each section 70, and ends when the trailing edge passes over the sensor unit 112 and reaches the next section 70. That is, the sensor image generating means 155 accumulates the sensor image sa in the time axis direction from the state shown in FIG. 22(b3) to the state shown in FIG. 22(b4), and ends accumulation of the sensor image sa when reflected light is no longer obtained from the sensor unit at (b4). That is, at this point, the entire sensor image sa has been obtained.

[0142] When the accumulation of the sensor image sa is completed, the detected transported object da of FIG. 22(c4) is determined by the detected transported object determination means 156 from the sensor image sa of FIG. 22(b4) accumulated in the time axis direction. That is, when the actual transported object a passes the rearmost sensor unit 112 and reaches the transport module (the point at which the second sensor unit 112 can no longer obtain reflected light, hereinafter also referred to as the reset timing), the detected transported object da of FIG. 22(c4) is determined by the detected transported object determination means 156 from the sensor image sa of FIG. 22(b4) accumulated in the time axis direction. At this point (reset timing), the virtual transported object ia is simultaneously reset (reset) to the obtained detected transported object da, as shown in FIG. 22(d4). Note that the third diagram marked (c) shows the shape and form of the transported object derived from the sensor image at the time of reset, and therefore appears only at the reset timing (hereinafter referred to as the reset timing). 21 and 22, the detected transported object da is formed by the detected transported object determining means 156 only at the reset timing, which in this example is only at the time of (c4) in Fig. 22. This also applies to the following drawings that explain other examples.

[0143] Next, using Figures 23 to 25, we will explain the operation when an object is transported from the first section 70a to the second section 70b in an attitude tilted relative to the transport direction. That is, we assume that the object is parallel to the traveling direction when it enters section 70a, but its attitude tilts midway through section 70a, and it enters from section 70a to the second section 70b. In this example, too, to clearly explain the detection operation of sensor unit 112, we will explain the following assuming that the virtual object on the transport device is only initialized when the actual object passes sensor unit 112b.

[0144] The actual conveyed object a progresses as shown in Figures 23(a1), (a2), 24(a3), (a4), 25(a5), and (a6). In Figure 23(a1), the actual conveyed object a is in the first section 70a, passes the second sensor unit 112b, and progresses to the second section 70b as shown in Figure 25(a6). At this time, as soon as the actual conveyed object a begins to pass over the second sensor unit 112b, the driving status detection means 163 of the central control device 153 begins to form a sensor image sa using the sensor image generation means 155, as shown in Figure 23(b2). That is, the sensor image sa is formed by accumulating images of the actual conveyed object a captured by the sensor unit 112b on the time axis. Here, the actual conveyed object a is tilted downward, so the width of the sensor image sa of the actual conveyed object a in Figure 23(a2) is narrower than the width of the actual conveyed object a. That is, a sensor image that is slightly narrower than that obtained when the beam advances in a parallel state (FIG. 23(b2)) is obtained.

[0145] When the actual conveyed object a further travels over section 70b and reaches the position shown in Figure 24(a3), the portion that was not reflected in Figure 23(a2) also reflects the light emitted from the sensor member 121, so the sensor image sa begins to form an image that extends downward from the middle, as shown in Figure 24(b3). When the actual conveyed object a further travels over section 70b and reaches the position shown in Figure 25(a5), the actual conveyed object a tilts its leading edge downward, causing its rear end to protrude upward. Therefore, as shown in Figure 25(b5), the sensor image sa at this position has an upwardly protruding portion. When the rear end of the actual conveyed object a passes over the second sensor unit 112b and reaches section 70b, the sensor image generating means 155 accumulates the sensor image sa in the time axis direction up to the state shown in Figure 25(b6). When the actual conveyed object a reaches the position shown in Figure 25(a6) and no reflected light is obtained from the sensor unit in Figure 25(b6), accumulation of the sensor image sa ends. That is, at this point, the entire sensor image sa is obtained.

[0146] At this point, i.e., at the reset timing, the detected transported object da in Fig. 25(c6) is determined from the sensor image sa in Fig. 25(b6) accumulated in the time axis direction by the detected transported object determination means 156. At this point when this actual transported object a passes over the rear end sensor unit 112 and reaches the section 70b, the virtual transported object ia is simultaneously reset (reset) to this obtained detected transported object da, as shown in Fig. 25(d6).

[0147] When the transported object enters section 70a, its posture is parallel to the direction of travel, so the posture of the virtual transported object is straight from d1 to d5. At this point when the actual transported object a passes over the rear end sensor unit 112 and reaches the transport module in section 70b, the posture of the virtual transported object ia is reset and it then assumes an inclined posture, as shown in Figure 25 (d6).

[0148] The conveying system 151 of this embodiment can determine whether multiple transported objects are being transported in parallel. Here, in this embodiment, parallel transport of the objects refers to a state in which at least portions of the multiple transported objects are present in the same area in the transport direction of the transport path. That is, parallel transport of the objects includes a case in which at least portions of the objects are traveling side by side in the same area in the transport direction of the transport path as viewed in a plan view, as shown in FIG. 19( a). That is, it includes a case in which the objects are traveling side by side. Furthermore, a case in which the objects are traveling while overlapping one above the other, as shown in FIG. 19( b), is also considered a state in which the objects are traveling in parallel.

[0149] Next, using Figures 26 to 28, we will explain the operation when two conveyed objects are conveyed overlapping each other from the first section 70a to the second section 70b. That is, we assume that there is a predetermined gap between actual conveyed object a and actual conveyed object b when they enter section 70a, but that actual conveyed objects a and b overlap midway through section 70a, and that they enter from section 70a to the second section 70b in an overlapping state. In this example, to clearly explain the detection operation of sensor unit 112, we will also assume that the virtual conveyed object on the conveying device is initialized only when the actual conveyed object passes sensor unit 112b.

[0150] The actual conveyed objects a and b proceed in an overlapping state as shown in Figures 26(a1), (a2), 27(a3), (a4), 28(a5), and (a6). In Figure 26(a1), the actual conveyed object a is in the first section 70a, passes the second sensor unit 112b, and proceeds to the second section 70b as shown in Figure 26(a2). At this time, among the overlapping actual conveyed objects a and b, when the leading actual conveyed object a begins to pass over the second sensor unit 112b, as shown in Figure 26(b2), the driving status detection means 163 of the central control device 153 begins to form a sensor image sa using the sensor image generation means 155. That is, the sensor image sa is formed by accumulating the images of the actual conveyed object a captured by the sensor unit 112b on the time axis. At this point, only the portion of the actual conveyed article a has reached the section 70b, and therefore, as shown in FIG. 26(b2), a sensor image sa having the same width as the actual conveyed article a is obtained.

[0151] When the actual conveyed objects a and b further travel along the section 70b and reach the position shown in Figure 27(a3), the actual conveyed object b also begins to reflect the light emitted from the sensor member 121, and the overlapping sensor images sa and sb begin to form an image that extends downward from the middle, as shown in Figure 27(b3). When the actual conveyed objects a and b further travel along the section 70b and reach the position shown in Figure 27(a4), the actual conveyed object a exceeds the second sensor unit 112b. Therefore, the rear portions of the sensor images sa and sb form an image with the width of the actual conveyed object b. When the rear end of the actual conveyed object b exceeds the second sensor unit 112b and reaches the conveying module, i.e., when it reaches Figure 28(a5), the reflected light from the sensor unit ceases to be received, and the accumulation of the sensor image sb ends. That is, at this point, the entire image of the sensor images sa and sb is obtained, as shown in Figure 28(b5).

[0152] At this reset timing, the detected transported objects da and db in Fig. 28(c5) are determined from the sensor images sa and sb in Fig. 28(b5) accumulated in the time axis direction by the detected transported object determination means 156. Then, at this point when the rear end of this actual transported object b passes the sensor unit 112 and reaches the transport module, the virtual transported objects ia and ib are reset (reset) to the states of the obtained detected transported objects da and db, as shown in Fig. 28(d5).

[0153] At this point when the actual transported objects a and b pass the rear end sensor unit 112 and reach the transport module in section 70b, the postures of the virtual transported objects ia and ib are reset, and thereafter the virtual transported objects a and b overlap. After this, the virtual transported objects ia and ib proceed on section 70b with the transport operation amount obtained by the virtual transported object operation amount determination means 185 of the transport state estimation means 162. If the actual transported objects a and b are being transported normally, they will exhibit the same movement as the virtual transported objects ia and ib, as shown in Figure 28 (a6).

[0154] Next, using Figures 29 and 30, we will explain the operation when the rear transported object pushes the front transported object and is transported from the first section 70a to the second section 70b as if they were a single transported object. That is, we will explain the operation when actual transported object a and actual transported object b enter section 70a with a predetermined gap between them, but the rear actual transported object b bumps into the leading actual transported object a midway through section 70a, and the two are transported from the first section 70a to the second section 70b as if they were a single transported object. Note that the width of actual transported object a is assumed to be smaller than the width of actual transport section b. Also, in this example, to clearly explain the detection operation of the sensor unit 112, we will assume that the virtual transported object on the transport device is only initialized when the actual transported object passes through sensor unit 112b. The actual transported objects a and b proceed as shown in Figures 29(a1), (a2), 30(a3), and (a4), with the rear transported object pushing the front transported object.

[0155] In Figure 29(a1), the actual conveyed object a is in the first section 70a, passes the second sensor unit (112b), and proceeds to the second section 70b as shown in Figure 29(a2). At this time, when the preceding actual conveyed object a begins to pass over the second sensor unit 112b, the drive status detection means 163 of the central control device 153 begins to form a sensor image sa using the sensor image generation means 155, as shown in Figure 29(b2). That is, the sensor image sa is formed by accumulating images of the actual conveyed object a captured by the sensor unit 112b on the time axis. At this point, only a portion of the actual conveyed object a has reached the section 70b, so a sensor image sa having the same width as the actual conveyed object a is obtained, as shown in Figure 29(b2).

[0156] When the actual conveyed objects a and b further advance along section 70b and reach the position shown in Figure 30 (a3), the actual conveyed object b begins to reflect the light emitted from the sensor member 121. Therefore, the width of the rear portions of the sensor images sa and sb is larger than the width of the front portions. In this example, the rear end of the actual conveyed object a is being pressed by the front end of the actual conveyed object b in a tight contact state. Therefore, the drive status detection means 163 recognizes the actual conveyed objects a and b as if they were a single conveyed object. Therefore, even when the rear end of the actual conveyed object a passes through sensor unit 112b, the sensor image generation means 155 does not reach the reset timing, so it does not instruct a reset operation and continues to accumulate the sensor images.

[0157] When the sensor images sa and sb, which are recognized as a state in which the actual conveyed objects a and b are integrated, continue to travel along the section 70b and reach the position shown in Figure 30(a4), the rear end of the actual conveyed object b exceeds the second sensor unit 112b. Therefore, the rear portions of the sensor images sa and sb form images with the width of the actual conveyed object b. When the rear end of the actual conveyed object b exceeds the second sensor unit 112b and reaches the conveying module, i.e., when it reaches Figure 30(a4), reflected light from the sensor unit is no longer obtained, and accumulation of the sensor image sb ends. That is, at this point, the entire sensor images sa and sb are obtained, as shown in Figure 30(b4).

[0158] From the sensor images sa and sb of Fig. 30(b4) accumulated in the time axis direction, the detected transported goods da and db of Fig. 30(c4) are determined by the detected transported goods determining means 156. At this point, as shown in Fig. 30(d4), the virtual transported goods ia and ib are reset (reset) to the states of the obtained detected transported goods da and db.

[0159] Thereafter, the virtual transported objects ia and ib proceed on the section 70b with the transport operation amount obtained by the virtual transported object operation amount determining means 185 of the transport state estimating means 162. If the actual transported objects a and b are transported normally, they will exhibit the same movements as the virtual transported objects ia and ib, as shown in Figures 30(a4) and (d4).

[0160] The following describes how the central control device 153 controls the conveying device 2 using the drive status detection means 163, which is a characteristic function of the conveying system 151 of the second embodiment described above. As a first example, the control by the central control device 153 when the posture of the actual conveyed object a changes during conveyance will be described with reference to Figures 31 to 35.

[0161] Each of Figures 31 to 35 shows a part of the conveying device 2 that conveys the article from upstream to downstream, with the left side of the figure being the upstream and the right side being the downstream, and shows the progress of the article over time. Each of Figures 31 to 35 illustrates the first section 70a to the third section 70c.

[0162] The article a is transported from the first compartment 70a on the far left side through the second compartment 70b to the third compartment 70c.

[0163] As shown in Figure 31 (a1), assume that actual transported object a has passed through the second sensor unit 112b from the first section 70a and been transported to the second section 70b. That is, the virtual transported object i a is assumed to have been reset to a position that does not cause delay relative to the movement of the normally operating actual transported object a at the reset timing (resetting timing) in the first section 70a, with the same shape, size, and posture as the actual transported object a. The following explanation will be given assuming that the actual transported object a is operating normally in the first section 70a. In this case, as shown in Figure 31 (d1), the virtual transported object i a at the time the transported object a is transported to the first section 70a or the second section 70b will have a virtual transport situation with almost the same shape, size, and posture as the actual transported object a.

[0164] Then, the actual conveyed object a moves forward in the second section 70b for a while without changing its posture as shown in Figures 31(a2), 32(a3), and (a4), and then, for some reason, changes its posture within the second section 70b to one in which its leading edge is tilted to the right with respect to the direction of travel as shown in Figure 33(a5). While maintaining this posture in which its leading edge is tilted to the right with respect to the direction of travel, the actual conveyed object a passes through the third sensor unit 112c and proceeds to the third section 70c as shown in Figures 33(a6), 34(a7), (a8), 35(a9), and (a10).

[0165] First, we will explain the control operations that occur when the actual conveyed object a passes over the second sensor unit 112b and completely reaches the second section 70b. At this time, the actual conveyed object a passes over the second sensor unit 112b and proceeds into the second section 70b as shown in Figures 31(a1), (a2), and 32(a3). At this time, the actual conveyed object a, including its rear end, passes over the second sensor unit 112b and completely reaches the second section 70b as shown in Figure 33(a4). As the actual conveyed object a passes over the second sensor unit 112b and begins to receive reflected light as shown in Figure 31(a1), the driving status detection means 163 of the central control device 153 begins forming an image of the actual conveyed object captured by the sensor unit 112b using the sensor image generation means 155. The resulting image then begins to accumulate. The area of ​​the sensor image sa increases as the actual conveyed object progresses through Figures 31(b1), (b2), and 32(b3). Here, as shown in FIG. 32(a4), let us assume that actual conveyed object a is conveyed in a parallel orientation to the conveying path until its rear end passes the second sensor unit 112b and is completely taken into the second section 70b. At this time, the sensor image sa becomes an image as shown in FIG. 32(b4). The detected conveyed object determination means 156 of the drive status detection means 163 then detects from the sensor image sa of FIG. 32(b4) that the detected conveyed object da shown in FIG. 32(c4) is the conveyed object that actually arrived at this second section 70b. At the same time, at this reset timing, the virtual conveyed object (ia) is reset (reset) to be parallel to the conveying path as shown in FIG. 32(d4). In other words, it does not assume an inclined orientation but maintains its orientation in the first section 70a.

[0166] Next, we will explain the control operations that occur when the actual transported object a passes the third sensor unit 112c and completely reaches the third section 70c. As the actual transported object a progresses from the state shown in FIG. 32(a4) to the state shown in FIG. 33(a5), its leading edge assumes a position tilted to the right relative to the direction of travel. Thereafter, it maintains this position shown in FIG. 33(a5) and travels parallel to the transport path. As described above, in the state shown in FIG. 33(d5), the virtual transported object ia maintains the transport state reset in FIG. 32(d4), i.e., a position parallel to the transport direction. Then, as the actual transported object a further progresses through the transport device 2 through FIGS. 33(a6), 34(a7), (a8), 35(a9), and (a10), it passes through the third sensor unit 112c and completely reaches the third section 70c, including its rear end, which corresponds to the next reset timing (FIG. 35(a10)).

[0167] When the actual transport module reaches the state shown in Figure 35(a10), the sensor image sa becomes as shown in Figure 35(b10). From this sensor image sa, the detected transported object determination means 156 of the drive status detection means 163 calculates the detected transported object da having the shape / size / posture shown in Figure 35(c10), and resets the shape / size / posture of the virtual transported object ia shown in Figure 35(d10) with this. Then, the virtual transported object ia with this shape / size / posture is allowed to proceed on the section 70 until the next reset timing.

[0168] As a second example, control by the central control device 153 when three articles are being transported and the two rearmost articles overlap during transport and are transported in this overlapping state will be described with reference to Figures 36 to 39. For ease of illustration, each section is shown significantly shorter than it actually is. Each of Figures 36 to 39 shows a portion of the transport device 2. From the upstream side (left side in the drawing), the sections are arranged as follows: a first section 70a, a second section 70b, a third section 70c, and a fourth section 70d, and a fifth section 70e on the downstream side (right side in the drawing). A first sensor unit 112a (not shown) is installed at the upstream tip of the first section 70a, a second sensor unit 112b at the upstream tip of the second section 70b, a third sensor unit 112c at the upstream tip of the third section 70c, a fourth sensor unit 112d at the upstream tip of the fourth section 70d, and a fifth sensor unit 112e at the upstream tip of the fifth section 70e. The progress of conveyance thereafter will be described assuming that the initial state (the states shown in Figures 36(a1), (b1), (c1), and (d1)) is a state in which three actual conveyed objects a, b, and c are being normally conveyed along the conveyance path in this order and these three conveyed objects have reached the reset timing. As shown in Figure 36(a1), at this point in time, the conveying device 2 assumes that the actual conveyed object a is at the reset timing position in the fourth section 70d, the actual conveyed object b is at the reset timing position in the third section 70c, and the actual conveyed object c has reached the reset timing position in the second section 70b. Therefore, the detected conveyed objects da, db, and dc of the actual conveyed objects a, b, and c become images as shown in Figure 36(c1), and based on this, the virtual conveyed objects ia, ib, and ic are reset (reset) as shown in Figure 36(d1). Note that, since the actual conveyed objects a, b, and c are operating normally, the virtual conveyed objects ia, ib, and ic are reset to approximately the same shape / size / posture as the actual conveyed objects.

[0169] Next, as shown in FIG. 36(a2), suppose that actual conveyed objects a and c are conveyed normally, but actual conveyed object b stops moving for some reason within the third section 70c. At this time, actual conveyed object a continues normal operation from section 70d to section 70e, as shown in FIG. 36(a2) and FIG. 37(a3). Then, when actual conveyed object a passes the fifth sensor unit 112e and is conveyed to the fifth section 70e, the drive status detection means 163 of the central control device 153 uses the sensor image generation means 155 to generate a sensor image sa as shown in FIG. 36(b2), FIG. 37(b3), and FIG. 37(b4). Since actual conveyed object a continues normal operation, it is assumed that the detected conveyed object determination means 156 of the drive status detection means 163 will calculate the detected conveyed object da when the fifth section 70e reaches the reset timing. Furthermore, it is assumed that the reset means 16 generates a virtual transported object ia that is approximately the same as the shape / size / posture of the actual transported object a from the detected transported object da calculated from this sensor image sa.

[0170] The actual conveyed object c in the third section 70c also continues its expected conveyance operation as shown in Figures 36(a2) and 37(a3). Therefore, when the actual conveyed object c passes the third sensor unit 112c and is conveyed into the third section 70c, the drive status detection means 163 of the central control device 153 uses the sensor image generation means 155 to generate a sensor image sc corresponding to the progress of the actual conveyed object c, as shown in Figures 37(b3), (b4), and 38(b5). Then, when the third sensor unit 112c no longer receives reflected light, i.e., when the reset timing is reached, the detected conveyed object determination means 156 of the drive status detection means 163 calculates Figure 38(c5) as the detected conveyed object dc. At this reset timing, the reset means 16 then designates the virtual conveyed object ic in Figure 38(d5) as the new virtual conveyed object ic. However, the actual transport situation is such that the actual transport modules b and c overlap as shown in FIG. 38(a5), and the actual transport situation cannot be grasped at this reset timing.

[0171] Next, the movement of actual transported object b will be described. As shown in FIG. 36(a2), it is assumed that actual transported object b has stopped moving within the third section 70c. Furthermore, as shown in FIGS. 37(a3) and (a4), actual transported object b initially remains motionless in the third section 70c, but actual transported object c approaches and eventually overlaps actual transported object b. In this state, it is assumed that actual transported objects b and c become one and start moving forward. Meanwhile, virtual transported object ib is reset (reconfigured) as shown in FIG. 36(d1), and thereafter, virtual transported object ib is transported as shown in FIG. 36(d2), FIG. 37(d3), (d4), and FIG. 38(d5). Then, in FIG. 38(d5), virtual transported object ib passes through the fourth sensor unit 112d and is completely transported, including its rear end, into the fourth section 70d. However, as described above, the actual transported object b is stuck in the third section 70c, and the detected transported object db, which should have reached Figure 38 (c5), is not present. Therefore, at this reset timing, the virtual transported object ib is reset (reset) to the "not present" state.

[0172] Thereafter, the overlapping actual conveyed objects b and c shown in Figure 38(a5) are conveyed from the third section 70c through the fourth sensor unit 112d and into the fourth section 70d as shown in Figures 38(a6), 39(a7), and 39(a8). In Figure 39(a8), the overlapping actual conveyed objects b and c, including their rear ends, are completely conveyed into the fourth section 70d, i.e., the next reset timing is reached. At this time, the sensor images sb and sc obtained by accumulating the images of the actual conveyed objects captured by the fourth sensor unit 112d on the time axis become the images shown in Figure 39(c8). From these sensor images sb and sc, the detected conveyed objects shown in Figure 39(c8) are calculated by the detected conveyed object determination means 156 of the drive state detection means 163, and are reset (reset) to the virtual conveyed objects ib and ic shown in Figure 39(d8) by the reset means 16. From the above, if an overlap occurs, the occurrence of the overlap can be recognized in section 70d, which is downstream of section 70c where the overlap occurred. Furthermore, if the widths of actual conveyed objects b and c are different, it is possible to identify which of the actual conveyed objects b and c, which are conveyed in an overlapping state, is conveyed first. In addition, since it is possible to confirm the existence of two actual conveyed objects, it is possible to determine that no objects were being removed. Note that when such an overlap occurs, it is possible to eliminate the overlap by implementing control measures, such as temporarily increasing the conveying speed and then suddenly slowing it down. This overlap detection function can also be used as a trigger to determine whether or not to implement such control, and is a function that can produce significant benefits in applications.

[0173] 43, for example, it is possible to set different conveying speeds for different positions within the section 70. That is, the conveying module 136 includes a plurality of conveying cells 141, and each conveying cell 141 includes a travel motor 149. Therefore, by setting the rotation speed of the travel motor 149 of each conveying cell 141 to a different value, it is possible to set the conveying rollers 143 of each conveying cell 141 to rotate at different speeds. For example, by rotating the front half of the section 70 at a high speed and the rear half at a low speed, it is possible to eliminate overlapping.

[0174] Each transport module 136 also has a swivel motor 148. Therefore, by rotating the swivel motor 148, the orientation of the swivel base 146 can be changed, which also makes it possible to change the orientation of the transport rollers 143.

[0175] As a third example, a case where an object stops moving due to a snag or other reason, but is then pushed by another object coming from behind and continues to be transported will be described using Figures 40 to 42, which show the operation of sections 70a, 70b, 70c, 70d, and 70e. For ease of illustration, each section in Figures 40 to 42 is shown significantly shorter than it actually is. Note that in this example, an object is being transported from the left side of the figure, i.e., the first section 70a, to the fifth section 70e to the right. From the upstream side (left side of the figure), the first section 70a, the second section 70b, the third section 70c, and the fourth section 70d are arranged, and then the fifth section 70e is arranged downstream (right side of the figure). A first sensor unit 112a (not shown) is installed at the upstream tip of the first section 70a, a second sensor unit 112b at the upstream tip of the second section 70b, a third sensor unit 112c at the upstream tip of the third section 70c, a fourth sensor unit 112d at the upstream tip of the fourth section 70d, and a fifth sensor unit 112e at the upstream tip of the fifth section 70e. In the third example, the first sensor unit 112a is not shown, but the following description will be given assuming that it is present. Furthermore, only the diagrams (a1) to (a6) showing the movement of the actual transported object are labeled with symbols.

[0176] As an initial state, as shown in FIG. 40(a1), assume that actual conveyed object a has completely reached the third section 70c, including its rear end, and that actual conveyed object b has completely reached the second section 70b, including its rear end, at the same time, reaching the position where the reset timing is performed. Also assume that conveyance is being carried out normally at this time. In the above state, the sensor images sa and sb of actual conveyed objects a and b are generated by the sensor image generating means 155 of the drive status detecting means 163 as shown in FIG. 40(b1). Therefore, the detected conveyed objects da and db are calculated by the detected conveyed object determining means 156 as shown in FIG. 40(c1), and based on this, the virtual conveyed objects ia and ib are set by the resetting means as shown in FIG. 40(d1).

[0177] At this time, it is assumed that the actual transported object a is being transported normally. Therefore, as shown in Figures 40(a2), 41(a3), (a4), 42(a5), and (a6), the actual transported object a is smoothly transported from the third section 70c to the downstream fourth section 70d and fifth section 70e. Therefore, the virtual transported object i a is calculated by the virtual transported object transport operation amount determining means 185 of the transport state estimating means 162 to proceed from the fourth section 70d to the fifth section 70e, as shown in Figures 40(d2), 41(d3), (d4), 42(d5), and (d6).

[0178] On the other hand, suppose that the actual conveyed item b becomes stuck in some way, as shown in Figures 40(a2) and 41(a3). At this time, suppose that the actual conveyed item c being conveyed next to the actual conveyed item b approaches the actual conveyed item b, and finally, as shown in Figures 41(a4) and 42(a5), the actual conveyed item c comes into contact with the actual conveyed item b and begins to push the actual conveyed item b. Furthermore, suppose that the force of the actual conveyed item c pushing the actual conveyed item b causes the actual conveyed item b to become unstuck, and the actual conveyed items b and c move forward together on the section 70.

[0179] At this time, the virtual transported object ib is calculated to move from the second section 70b to the third section 70c as shown in Figures 40(d2), 41(d3), and (d4), and arrives at Figure 41(d4). Here, the virtual transported object ib passes through the sensor unit 112c and completely reaches the third section 70c, including its rear end. Therefore, the reset timing is reached at this time. Here, the actual transported object b, as shown in Figures 40(a2) and 41(a3), was in a stopped state for a while until it was pushed by the actual transported object c. Therefore, as shown in Figure 41(a4), the leading edge of the actual transported object b passes through the third sensor unit 112c and reaches the reset timing of the third section 70c much later than the virtual transport section ib. Therefore, at this reset timing, the detected transported object db does not occur, as shown in Figure 41(c4). Therefore, at this reset timing, the detected transported object determining means 156 of the driving status detecting means 163 determines that the virtual transported object ib does not exist, and it disappears as shown in FIG. 41(d4).

[0180] At this time, as shown in Figure 41 (a4), the actual conveyed object b is pushed by the actual conveyed object c and begins to move, albeit with a time delay. Therefore, when the leading edge of the actual conveyed object b passes the third sensor unit 112c and it becomes possible to receive reflected light, the sensor image generating means 155 begins accumulating the sensor image sb generated by the third sensor unit 112c. Here, the actual conveyed object b is in contact with the actual conveyed object c and is conveyed as a single unit. Therefore, the sensor image sb is conveyed with its rear end in contact with the sensor image sc, and the sensor images sb and sc are formed as if they were a single conveyed object, as shown in Figure 41 (b4), Figure 42 (b5), and then Figure 42 (b6).

[0181] Upon receiving these sensor images sb and sc, the detected conveyed object determination means 156 of the drive status detection means 163 creates the detected conveyed objects db and dc shown in FIG. 42(c6). Here, if the widths of the actual conveyed objects b and c are different, it is possible to identify which of the two actual conveyed objects is actual conveyed object b and which is actual conveyed object c. Furthermore, when such contact between conveyed objects occurs, it is possible to return the spacing between the conveyed objects to the normal spacing, for example, by increasing the conveying speed of the preceding actual conveyed object and decreasing the conveying speed of the following actual conveyed object. For example, this can be achieved by using the conveying module 136 shown in FIG. 43.

[0182] Using the transport module of Figure 43, when an actual transported object is recognized as being transported in an inclined position as shown in Figure 35 (a10), it is possible to make the orientation parallel to the transport direction. For example, this can be achieved by making the transport speed of the upper transport cell of the transport module slower than that of the lower transport cell. When using the transport module of Figure 43, when two actual transported objects b and c are recognized as being transported in a state where the rear transported object pushes the front transported object and is transported as if they were one object, as shown in Figure 42 (a6), it is possible to correct the situation so that the two transported objects b and c are transported in this state with a gap between them. This can be achieved by making the transport speed of the transport cell in contact with object b faster than the transport speed of the transport cell in contact with object c.

[0183] Furthermore, by using the conveying system 1 of the second embodiment described above, it is also possible to detect an abnormality that occurs when an object is taken out or put in. That is, if the objects have different widths or lengths, it is possible to identify the object that is missing from the planned conveying schedule by checking the width or length of the object being conveyed on the conveying module.

[0184] In the embodiment described above, the transport state estimation means 162 is provided, and the transport state estimation means 162 estimates that the transported object will move in a straight line. That is, in the embodiment described above, the transport state estimation means 162 has a function of estimating the transport posture of the transported object as it is being transported under an estimated transport situation. However, this embodiment is not limited to this configuration, and the transport state estimation means may not have the function of estimating the transport posture of the transported object. That is, the transport posture of the transported object may be compared by the comparison means on the assumption that the transported object will move in a straight line. That is, the modified conveying system has a conveying device, a plurality of sensors, and a comparison means, and the conveying device is configured to place actual conveyed objects and actually move the actual conveyed objects, and at least one of the plurality of sensors is a sensor group, and the sensor group is configured to have a plurality of sensor elements arranged in a direction intersecting the conveying direction of the conveyed objects, and the parallel running and / or conveying posture of the conveyed objects is detected using information detected by each sensor element of the sensor group regarding the operation timing of the sensor element, and the normal conveying posture of the conveyed object is compared with the parallel running and / or conveying posture of the actual conveyed object detected by the sensor using the comparison means.

[0185] 1, 151 Conveying system 2 Conveying device 5a First section sensor 5b Second section sensor 6 Conveying module 8 Information reading means 11 Conveyor control means 12, 162 Conveying state estimating means 13, 163 Driving condition detecting means 15 Existence area 16 Reset means 20 Front limit line 21 Rear limit line 28, 158 Comparison means 30 Conveyed object information storage means 35 Estimated pulse calculation means 36 Leading end side expected conveying operation amount determining means 37 Rear end side expected conveying operation amount determining means 53 Leading end comparison means 55 Rear end comparison means 105a Virtual first section sensor 105b Virtual second section sensor 112 Sensor group (sensor unit) 121 Sensor member

Claims

1. A conveying system for conveying a plurality of objects to their respective destinations, comprising a conveying state estimation means, a conveying device, a plurality of sensors, and a comparison means, wherein the conveying state estimation means estimates an estimated conveying state in which the objects are conveyed by the conveying device, the conveying device carries the actual objects and actually moves the actual objects, the sensor is located at a predetermined position and detects the actual objects on the conveying device, and the conveying system is characterized in that the comparison means compares the estimated conveying state of the objects estimated by the conveying state estimation means with the actual conveying state of the objects detected by the sensor.

2. The conveying system described in claim 1, characterized in that the conveying state estimation means estimates the operation timing of the sensor under the estimated conveying state, and has a driving state detection means, which detects the operation timing of the sensor under the actual driving state of the conveying device.

3. The conveying system according to claim 1 or 2, characterized in that the conveying state estimation means estimates the rotational state of a specific component and / or the time required to transport the transported item under the estimated conveying state, and has a driving state detection means which detects the rotational state of a specific component and / or the time required to transport the transported item.

4. A conveying system as described in any one of claims 1 to 3, characterized in that the conveying state estimation means estimates the conveying posture of the conveyed object as it is conveyed under the estimated conveying state, at least one of the multiple sensors is a sensor group, the sensor group consisting of multiple sensor elements arranged in a direction intersecting the conveying direction of the conveyed object, the parallel running and / or conveying posture of the conveyed object is detected as the actual conveying state using information regarding the operation timing of each sensor element of the sensor group detected by that sensor element, and the conveying posture of the conveyed object estimated by the conveying state estimation means is compared with the actual parallel running and / or conveying posture of the conveyed object detected by the sensor by the comparison means.

5. The conveying device has a conveying member that performs a rotating or running conveying operation, and moves the conveyed object by performing a conveying operation of the conveying member, the conveying state estimation means estimates a tip-side predicted conveying operation amount that is the minimum value of the conveying operation amount that is expected when the tip of the conveyed object moves normally and is detected by a sensor at a specified position, the conveying device has a driving status detection means that acquires an actual conveying operation amount that is the actual conveying operation amount of the conveying device, and the comparison means performs a front end comparison to compare the actual conveying operation amount when the actual tip of the conveyed object is detected by a sensor at a specified position with the tip-side predicted conveying operation amount. A conveying system as described in any one of claims 1 to 4.

6. The conveying device has a conveying member that performs a rotating or running conveying operation, and moves the conveyed object by performing a conveying operation of the conveying member, the conveying state estimation means estimates a predicted rear end side conveying operation amount, which is the maximum conveying operation amount that is expected when the rear end of the conveyed object moves normally and is detected by a sensor at a specified position, the conveying device has a driving status detection means that acquires an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and the comparison means performs a rear end comparison to compare the actual conveying operation amount when the actual rear end of the conveyed object is detected by a sensor at a specified position with the predicted rear end side conveying operation amount. A conveying system as described in any one of claims 1 to 5, characterized in that:

7. The conveying system according to any one of claims 1 to 6, characterized in that, when there is a difference between the estimated conveying status and the actual conveying status by a certain amount or more as a result of the comparison by the comparison means, at least one of the following processes is carried out: (1) changing the conveying speed of the conveying device, (2) correcting the estimated conveying status of the conveying status estimation means, (3) changing the destination of the conveyed object, (4) stopping the conveying device, (5) changing the conveying route, and (6) notifying.

8. A conveying system in which a plurality of objects are conveyed to their respective destinations by a conveying device, the conveying device having a conveying member that performs a rotating or running conveying operation, and moving the objects by conveying the conveying member, characterized in that the conveying system has a leading end prediction means for predicting a leading end predicted conveying operation amount, which is the minimum value of the conveying operation amount that is predicted when the leading end of the object is detected by a sensor at a specified position in the case of normal movement, a driving status detection means for acquiring an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and a front end comparison means for comparing the actual conveying operation amount with the leading end predicted conveying operation amount when the actual leading end of the object is detected by a sensor at a specified position.

9. A conveying system in which a plurality of objects are conveyed to their respective destinations by a conveying device, the conveying device having a conveying member that performs a rotating or running conveying operation, and moving the objects by conveying the conveying member, characterized in that the conveying system has a rear end side prediction means for predicting a rear end side predicted conveying operation amount, which is the maximum conveying operation amount that is predicted when the rear end of the object is moved normally and detected by a sensor at a specified position, a driving status detection means for acquiring an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, and a rear end comparison means for comparing the actual conveying operation amount when the actual rear end of the object is detected by a sensor at a specified position with the rear end side predicted conveying operation amount.

10. A conveying system in which a plurality of objects are conveyed to their respective destinations by a conveying device, the conveying device having a conveying member that performs a rotating or running conveying operation, and moving the objects by conveying the conveying member, the conveying system having a leading end prediction means for predicting a leading end predicted conveying operation amount, which is the minimum value of the conveying operation amount that is predicted when the leading end of the object is detected by a sensor at a predetermined position in the case of normal movement, a rear end prediction means for predicting a rear end predicted conveying operation amount, which is the maximum value of the conveying operation amount that is predicted when the rear end of the object is detected by a sensor at a predetermined position in the case of normal movement, a driving status detection means for acquiring an actual conveying operation amount, which is the actual conveying operation amount of the conveying device, a leading end comparison means for comparing the actual conveying operation amount with the leading end predicted conveying operation amount when the actual leading end of the object is detected by the sensor at the predetermined position, and a rear end comparison means for comparing the actual conveying operation amount with the rear end predicted conveying operation amount when the actual rear end of the object is detected by the sensor at the predetermined position.

11. A conveying system as described in any one of claims 1 to 10, characterized in that at least one of the plurality of sensors is a sensor group, the sensor group being a plurality of sensor elements arranged in a direction intersecting with the conveying direction of the transported object.

12. The conveying system according to claim 4, characterized in that the parallel running of the transported objects is eliminated or the transporting posture is changed based on the result of the detection operation.

13. A conveying system as described in any one of claims 1 to 12, characterized in that when an abnormality is detected due to a delayed or early arrival of a transported item, or an item being removed or inserted, the deviation between the expected conveying status and the actual conveying status is reset, and the expected conveying status is re-set to match the detected actual conveying status.

14. A conveying system as described in any one of claims 1 to 13, characterized in that after the transported item reaches or passes through the sensor, an estimated transport situation is reset to match the detected actual transport situation.

15. A conveying system for conveying a plurality of objects to their respective destinations, comprising a conveying device, a plurality of sensors, and a comparison means, wherein the conveying device is configured to place actual objects on the conveying device and actually move the actual objects, at least one of the plurality of sensors is a sensor group, the sensor group being configured to have a plurality of sensor elements arranged in a direction intersecting with the conveying direction of the objects, the parallel running and / or conveying posture of the objects is detected using information detected by each sensor element of the sensor group regarding the operation timing of the sensor element, and the comparison means compares the normal conveying posture of the objects with the actual parallel running and / or conveying posture of the objects detected by the sensor.

16. A conveying system according to any one of claims 1 to 15, characterized in that the conveying device has a conveying path that branches into multiple paths and has multiple destinations, and the conveying order of the objects corresponds to the destinations of the objects.

Images