Article transport apparatus

Abstract

An article transport apparatus is provided. An article transport vehicle traveling along a travel path is provided with: an obstacle sensor that detects an obstacle present in a detection region; and a control section that controls a travel speed of the article transport vehicle based on detection information of the obstacle sensor; a non-detection region in which detection of an obstacle by the obstacle sensor is not performed is set within a detectable region of the obstacle sensor; a situation in which the non-detection region is present on a detection line that links a portion of the detection region and the obstacle sensor is taken as a specific situation; and the control section decelerates the article transport vehicle to a second travel speed that is lower than a first travel speed in a situation in which the specific situation is present and a situation in which a non-detectable region in which an obstacle cannot be detected in the detection region becomes present due to a shield being present in the non-detection region.

Description

Technical Field

[0001] This invention relates to a goods conveying device having a goods conveying vehicle that travels along a driving path to transport goods. Background Technology

[0002] As such a goods transport device, for example, the structure described in Japanese Patent Application Publication No. 2018-177037 (Patent Document 1) is known. In the following description of the background art, reference numerals or names in parentheses are reference numerals or names from prior art documents. In the goods transport device described in Patent Document 1, the goods transport vehicle (3) includes: an obstacle sensor (obstacle detection sensor 21) that detects obstacles present in a detection zone (E), the detection zone (E) being set to match the shape of a predetermined travel trajectory on the front side of the goods transport vehicle; and a control unit (H) that controls the travel speed of the goods transport vehicle based on the detection information from the obstacle sensor. Thus, by including an obstacle sensor in the goods transport vehicle, the traveling goods transport vehicle can detect obstacles present in a predetermined travel trajectory. Summary of the Invention

[0003] An obstacle sensor may have the following structure: it has a detectable range capable of detecting obstacles, and it can designate a portion of the detectable range as a detection area for actually detecting obstacles, while designating the remaining range as a non-detection area where obstacles are not detected. Specifically, for example, an obstacle sensor may have the following structure: it can project detection light across the entire detectable range to detect obstacles within the detectable range, but it can be configured to not detect obstacles in the non-detection areas even if they are present.

[0004] When an obstacle sensor is installed in a transport vehicle, due to the curvature of the detection area, there may be obstructions in the non-detection area along the line connecting a part of the detection area to the obstacle sensor. In such cases, because the detection light projected by the obstacle sensor is blocked by the obstruction, it is possible that the detection light cannot reach a part of the detection area, resulting in an undetectable area where obstacles cannot be detected within the area that should be detected. In such situations, contact between the transport vehicle and the obstacle should be avoided, but control technology for transport vehicles that envisions such a scenario is currently unknown.

[0005] Therefore, it is desirable to have a material transport device that can properly control the material transport vehicle and prevent it from coming into contact with obstacles, even when there are undetectable areas in the area where obstacles should be detected.

[0006] The characteristic structure of the article conveying device disclosed herein includes an article conveying vehicle that travels along a travel path to convey articles; the article conveying vehicle includes: an obstacle sensor that detects obstacles existing in a detection area, the detection area being set to match the shape of a predetermined travel trajectory on the front side of the article conveying vehicle; and a control unit that controls the travel speed of the article conveying vehicle based on the detection information of the obstacle sensor; a non-detection area is set in the area within the detectable area of ​​the obstacle sensor that deviates from the predetermined travel trajectory, where the obstacle is not detected by the obstacle sensor; a specific condition is defined as the existence of the non-detection area on the detection line connecting a part of the detection area to the obstacle sensor due to the curvature of the detection area; and the control unit decelerates the article conveying vehicle to a second travel speed lower than the first travel speed when the article conveying vehicle is traveling at a first travel speed, in the aforementioned specific condition, and in the case where there is an undetectable area in the detection area where the obstacle cannot be detected due to the presence of an obstruction in the non-detection area.

[0007] According to this structure, within the detectable area of ​​the obstacle sensor, a detection zone is set with a shape matching the predetermined travel trajectory of the front side of the goods transport vehicle, and a non-detection zone is set in the area deviating from the predetermined travel trajectory where obstacle detection is not performed. Therefore, obstacles existing on the predetermined travel trajectory can be detected by the obstacle sensor, and the goods transport vehicle can be driven appropriately based on the detection results.

[0008] Here, depending on the shape of the predetermined travel trajectory on the front side of the transport vehicle, there may be a curved detection zone. Consequently, there may be a specific situation where a non-detection zone exists on the detection line connecting a portion of the detection zone to the obstacle sensor. In such a situation, if there is an obstruction in the non-detection zone, an undetectable zone may exist within the detection zone due to the presence of that obstruction. If an obstacle exists in such an undetectable zone, the transport vehicle may come into contact with it because it cannot be detected in advance by the obstacle sensor. However, according to this structure, when the transport vehicle is traveling at a first speed, and the aforementioned specific situation occurs, and an undetectable zone exists in the detection zone due to an obstruction in the non-detection zone, the transport vehicle's speed is reduced from the first speed to the second speed regardless of the actual presence or absence of an obstacle in the undetectable zone. Therefore, even if an obstacle exists in the undetectable zone, the transport vehicle can be stopped quickly. That is, the transport vehicle can be appropriately controlled to prevent contact with obstacles. Attached Figure Description

[0009] Figure 1This is a top view of the goods conveying equipment.

[0010] Figure 2 This is a side view of the goods transport vehicle.

[0011] Figure 3 This is the front view of the goods transport vehicle.

[0012] Figure 4 It is a control block diagram.

[0013] Figure 5 This is a diagram representing the detectable area.

[0014] Figure 6 This is a diagram representing the first detection zone.

[0015] Figure 7 This is a diagram representing the first detection area when there are branches.

[0016] Figure 8 This is a diagram representing the second detection zone.

[0017] Figure 9 This is a graph showing the changes in the detection area.

[0018] Figure 10 This is a graph showing the changes in the detection area.

[0019] Figure 11 This is a graph showing the changes in the detection area.

[0020] Figure 12 This is a graph showing the changes in the detection area.

[0021] Figure 13 This is a graph showing the changes in the detection area.

[0022] Figure 14 This is a graph representing the obstacle detection distance.

[0023] Figure 15 This is a diagram showing the detection area when the transport vehicle stops at the designated stop position.

[0024] Figure 16 It is a diagram representing the detection area where there is an undetectable area.

[0025] Figure 17 This is a graph showing the speed changes of the goods transport vehicle as it detects obstacles. Detailed Implementation

[0026] 1. Implementation Method

[0027] The implementation of the material conveying equipment is described based on the accompanying drawings.

[0028] like Figures 1 to 3As shown, the item conveying equipment includes an item conveying vehicle 3 that travels along a travel path 1 to transport item W. In this embodiment, in addition to the item conveying vehicle 3, the item conveying equipment also includes a travel track 2 provided along the travel path 1. The item conveying vehicle 3 travels along the travel path 1 while being guided by the travel track 2. Furthermore, in this embodiment, the item conveying vehicle 3 transports a FOUP (Front Opening Unified Pod) containing a semiconductor substrate as item W.

[0029] like Figure 1 As shown, the travel path 1 includes a main circular path 4, secondary circular paths 5 passing through multiple item handling units, and connecting paths 6 connecting the main path 4 and the secondary paths 5. The travel path 1 includes multiple secondary paths 5. The item transport vehicle 3 travels in the same circular direction (clockwise in this embodiment) in both the main path 4 and the multiple secondary paths 5. Furthermore, in... Figure 1 In the diagram, the direction of travel of the goods transport vehicle 3 is indicated by an arrow. As a connecting path 6, there is a branch connecting path 6 for the goods transport vehicle 3 to travel from the main path 4 toward the secondary path 5, and a merging connecting path 6 for the goods transport vehicle 3 to merge from the secondary path 5 toward the main path 4.

[0030] The driving path 1 includes a straight section 1A that is set as a straight line and a curved section 1B that is set as a curve. Specifically, the main path 4 is formed by a pair of parallel straight sections 1A and a pair of curved sections 1B that connect the ends of the pair of straight sections 1A to each other. Multiple sub-paths 5 are formed, similarly to the main path 4, by a pair of straight sections 1A and a pair of curved sections 1B. Connecting paths 6 are formed by curved sections 1B that connect to the main path 4 and straight sections 1A that connect to the sub-paths 5. Thus, the driving path 1 is set by combining straight sections 1A and curved sections 1B.

[0031] Next, the transport vehicle 3 will be explained. The direction along the travel path 1 will be referred to as the path length direction X, and the direction orthogonal to the path length direction X when viewed along the vertical direction Z will be referred to as the path width direction Y. Furthermore, the direction of travel of the transport vehicle 3 along the travel path 1 will be referred to as the forward direction. Incidentally, for example, when the transport vehicle 3 travels along the straight section of the travel path 1, the forward / backward direction of the transport vehicle 3 is the same as the path length direction X of the travel path 1, and the left / right direction of the transport vehicle 3 is the same as the path width direction Y of the travel path 1.

[0032] In this embodiment, such as Figure 2 and Figure 3As shown, the goods transport vehicle 3 includes: a traveling unit 9 that travels along a traveling track 2 that is suspended from the roof; and a main body 10 located below the traveling track 2 and suspended and supported by the traveling unit 9. The main body 10 includes a support mechanism 13 that is flexibly mounted on the main body 10 and supports the goods W in a suspended state.

[0033] The traveling unit 9 includes a first traveling mechanism 9F and a second traveling mechanism 9R arranged in the front-rear direction of the transport vehicle 3. The first traveling mechanism 9F includes an electric traveling motor 14 and a pair of left and right traveling wheels 15 driven by the motor 14. These left and right traveling wheels 15 are configured to roll on the upper surface of the traveling track 2 (a pair of left and right track sections 7). Furthermore, the first traveling mechanism 9F includes a pair of left and right guide wheels 16 that can rotate freely about a longitudinal axis (about the vertical axis) in the vertical direction Z. These left and right guide wheels 16 are configured to be located between the left and right track sections 7 and roll on opposite sides of the track sections 7. Additionally, two sets of the left and right guide wheels 16 are provided in the first traveling mechanism 9F, arranged in the front-rear direction. The second traveling mechanism 9R, like the first traveling mechanism 9F, includes one set of left and right traveling wheels 15 and two sets of left and right guide wheels 16.

[0034] The first traveling mechanism 9F and the second traveling mechanism 9R each have a connecting shaft 19 protruding downward from the lower end of the traveling wheel 15. The connecting shaft 19 of the first traveling mechanism 9F and the main body 10 are rotatably connected relative to each other about a longitudinal axis in the vertical direction Z. The connecting shaft 19 of the second traveling mechanism 9R and the main body 10 are rotatably connected relative to each other about a longitudinal axis in the vertical direction Z.

[0035] The transport vehicle 3 is guided by a pair of travel tracks 2 via guide wheels 16 of the first travel mechanism 9F and the second travel mechanism 9R, and its position in the path width direction Y is restricted. Simultaneously, the travel wheels 15 of the first travel mechanism 9F and the second travel mechanism 9R are driven to rotate by a travel motor 14, allowing it to travel along the travel path 1. Furthermore, the transport vehicle 3 oscillates relative to the main body 10 about its longitudinal axis via the first travel mechanism 9F and the second travel mechanism 9R, enabling it to travel along the travel path 1 even on curved sections 1B.

[0036] like Figure 4 As shown, the goods transport vehicle 3 is equipped with an obstacle sensor 21, a travel distance sensor 22, a position detection sensor 23, and a control unit H. Figures 5 to 16As shown, obstacle sensor 21 detects obstacles S present in detection area E2, which is set to match the shape of a predetermined travel path C on the front side of the transport vehicle 3. In this embodiment, obstacle sensor 21 is constructed using a distance sensor that utilizes light, such as a laser. Obstacle sensor 21 considers other transport vehicles 3 present on the front side of the transport vehicle 3 equipped with obstacle sensor 21, as well as people, objects, etc., that intrude into the travel path of transport vehicle 3, as obstacles S. Travel distance sensor 22 is constructed of rotary encoder or the like and measures the travel distance of transport vehicle 3 from a reference position set on travel path 1. Position detection sensor 23 detects multiple objects T (see reference 1) that are set along travel path 1. Figure 3 Location information is obtained through this process.

[0037] Travel path 1 is the hypothetical path that the goods transport vehicle 3 should travel. Travel path 1 is defined by the shape of the travel track 2. The control unit H stores travel map information. The travel map information is information that establishes a correlation between location information representing specific positions such as the location of the detected object T and the designated stop position V, which is set as the transfer position of the goods W, and basic map information that is information about the shape and connection relationship of travel path 1. Based on the detection information of the travel distance sensor 22, the detection information of the position detection sensor 23, and the travel map information, the control unit H determines the position of the goods transport vehicle 3 in travel path 1. Then, if a command is sent from the upper controller, the control unit H sets a path for transporting the goods W from the transport source specified by the transport command to the transport target based on the travel map information, and controls the goods transport vehicle 3 to travel along the set path to transport the goods W from the transport source to the transport target.

[0038] Furthermore, the control unit H stores travel speed information, which represents the travel speed of the goods transport vehicle 3, in a state associated with the travel map information. In this embodiment, a reference travel speed is set according to the shape of the travel path 1, and the reference travel speed of the goods transport vehicle 3 when traveling on the curved section 1B is set lower than the reference travel speed of the goods transport vehicle 3 when traveling on the straight section 1A. Specifically, a straight-line travel speed is set as the reference travel speed when traveling on the straight section 1A, and a curved-line travel speed, which is slower than the straight-line travel speed, is set as the reference travel speed when traveling on the curved section 1B. In addition, the straight-line travel speed and the curved-line travel speed set as reference travel speeds are equivalent to a first travel speed.

[0039] When the transport vehicle 3 travels from the straight section 1A towards the curved section 1B, the control unit H changes the reference speed from the straight-line speed to the curved-line speed before entering the curved section 1B. This reduces the transport vehicle 3's speed from the straight-line speed to the curved-line speed. The transport vehicle 3 then enters the curved section 1B at the curved-line speed and continues to travel at the curved-line speed within the curved section 1B. Conversely, when the transport vehicle 3 travels from the curved section 1B towards the straight section 1A, the control unit H changes the reference speed from the curved-line speed to the straight-line speed after entering the straight section 1A. This accelerates the transport vehicle 3's speed from the curved-line speed to the straight-line speed within the straight section 1A. The transport vehicle 3 then travels at the straight-line speed within the straight section 1A.

[0040] like Figure 5 As shown, the obstacle sensor 21 is configured to detect an obstacle S present in the detectable area E1 and to measure the distance to the obstacle S. In this embodiment, the obstacle sensor 21 is configured to rotate the projection part of the laser for obstacle detection around the longitudinal axis to detect the obstacle S within the detectable area E1, which is fan-shaped when viewed vertically, centered on the obstacle sensor 21. Furthermore, in this embodiment, the obstacle sensor 21 is mounted on the front end of the transport vehicle 3, projecting the laser for obstacle detection along the detection line Q from the front side to the lateral side (both sides in the left and right direction), forming a planar detectable area E1 with a semi-circular shape of radius L1 on the front side of the transport vehicle 3. Moreover, the obstacle sensor 21 is configured to change the shape of the detection area E2 set within the detectable area E1 based on instructions from the control unit H.

[0041] like Figure 5 As shown, obstacle sensor 21 defines a detection area E2 within the detectable area E1. In this embodiment, obstacle sensor 21 is configured as follows: Figures 5 to 7 The first detection zone EA, set as shown, is in a straight line when the straight section 1A is traveling. Figure 8 The second detection zone EB is set in a curved shape when the vehicle is traveling on the curved section 1B, as shown. Furthermore, in this embodiment, the lengths of the first detection zone EA and the second detection zone EB are varied according to the travel speed of the transport vehicle 3. That is, Figure 5 The item transport vehicle 3 shown is compared to Figure 6 The transport vehicle shown is traveling at a high speed. Figure 5 The length L2 of the first detection region EA shown becomes greater than Figure 6 The length L3 of the first detection region EA shown is [length missing]. Additionally... Figure 5The first detection zone EA represents the area where the transport vehicle 3 travels at a straight-line speed. Thus, the higher the speed of the transport vehicle 3, the longer the first detection zone EA is set. Furthermore, the second detection zone EB is set to a shape corresponding to the radius of curvature of the curved section 1B, and like the first detection zone EA, the longer the transport vehicle 3 travels, the longer the area is set. Moreover, the control unit H sets the detection zone E2 so that the length of the detection zone E2 along the travel path 1 increases as the speed of the transport vehicle 3 increases.

[0042] In this embodiment, the first detection area EA and the second detection area EB are formed into a strip shape when viewed along the vertical direction Z. In the first detection area EA, as shown... Figure 5 , Figure 6 and Figure 8 As shown, the width W2 in the path width direction Y is set to be narrower than the width W1 in the path width direction Y of the transport vehicle 3. This is the first detection area EA, and... Figure 7 The first detection zone EA is set to be wider than the width of the transport vehicle 3 protruding in the path width direction Y, as shown. When the first detection zone EA is located at the branch or merging point of the travel path 1, by setting the first detection zone EA to be wider, it is also possible to detect other transport vehicles 3 that exist in the branch or merging paths besides the path in which the transport vehicle 3 travels.

[0043] like Figures 9 to 13 As shown, when the transport vehicle 3 travels from the straight section 1A towards the curved section 1B, the obstacle sensor 21 sets up a region where the first detection area EA and the second detection area EB coexist, so that the detection area E2 has a shape that matches the travel path 1. That is, the shape of the detection area E2 is set in such a way that it changes sequentially from the straight first detection area EA to the curved second detection area EB from the front side of the detection area E2. Furthermore, when the transport vehicle 3 travels from the curved section 1B towards the straight section 1A, the obstacle sensor 21 also sets up a region where the first detection area EA and the second detection area EB coexist, so that the detection area E2 has a shape that matches the travel path 1. That is, the shape of the detection area E2 is set in such a way that it changes sequentially from the curved second detection area EB to the straight first detection area EA from the front side of the detection area E2.

[0044] Based on the detection information from the travel distance sensor 22, the position detection sensor 23, and the travel map information, the control unit H determines the position of the transport vehicle 3 in the travel path 1, and also determines the shape of the travel path 1 in front of the transport vehicle 3. Then, the control unit H sets the detection area E2 by constantly changing the shape to match the shape of the travel path 1 in front of the transport vehicle 3. Thus, the detection area E2 is set to match the shape of the travel path 1 in front of the transport vehicle 3 (the shape of the predetermined travel trajectory C).

[0045] In addition, such as Figure 5 As shown, within the detectable area E1 of the obstacle sensor 21 and in the region deviating from the predetermined driving trajectory C, a non-detection area E3 is defined where the obstacle S is not detected by the obstacle sensor 21. In this embodiment, the area within the detectable area E1 and excluding the detection area E2 (the first detection area EA and the second detection area EB) is designated as the non-detection area E3. The obstacle sensor 21 does not detect the obstacle S even if it exists in the non-detection area E3, but detects the obstacle S if it exists in the detection area E2.

[0046] If the control unit H does not detect an obstacle S in the detection zone E2, it causes the transport vehicle 3 to travel at a reference speed (straight-line speed or curved-line speed). If an obstacle S is detected in the detection zone E2, the control unit H decelerates the transport vehicle 3 to an emergency speed lower than the reference speed. Then, the distance along the travel path 1 from the transport vehicle 3 to the obstacle S detected in the detection zone E2 is taken as the obstacle detection distance L5 (refer to...). Figure 14 The control unit H sets the emergency driving speed so that the emergency driving speed decreases as the obstacle detection distance L5 decreases.

[0047] In this embodiment, such as Figure 17As shown, multiple speeds are set as emergency driving speeds. These multiple emergency driving speeds are all set to be lower than the straight-line driving speed. Furthermore, some of the multiple emergency driving speeds are set to be lower than the curve driving speed. In this embodiment, six emergency driving speeds (first emergency driving speed R1 to sixth emergency driving speed R6) are set as multiple emergency driving speeds. Moreover, all six emergency driving speeds are set to be lower than the straight-line driving speed. Additionally, the third emergency driving speed R3, one of the six emergency driving speeds, is set to the same speed as the curve driving speed, while the fourth emergency driving speed R4 to the sixth emergency driving speed R6 are set to be lower than the curve driving speed. In this embodiment, for both straight lines and curves, the emergency driving speed lower than the reference driving speed (first driving speed) corresponds to the third driving speed. Furthermore, in this embodiment, the sixth emergency driving speed R6 is set to zero (stop).

[0048] Furthermore, the control unit H sets an emergency travel speed so that the emergency travel speed decreases as the obstacle detection distance L5 decreases. For example, when the goods transport vehicle 3 is traveling at a straight-line travel speed, if an obstacle S is detected by the obstacle sensor 21, the travel speed of the goods transport vehicle 3 is changed in the following order from the straight-line travel speed: first emergency travel speed R1, second emergency travel speed R2, third emergency travel speed R3, fourth emergency travel speed R4, fifth emergency travel speed R5, and sixth emergency travel speed R6, as the obstacle detection distance L5 decreases. As a result, the travel speed of the goods transport vehicle 3 gradually decreases and stops at the sixth emergency travel speed R6. Additionally, for example, when the goods transport vehicle 3 is traveling at a curved-course travel speed, if an obstacle S is detected by the obstacle sensor 21, the travel speed of the goods transport vehicle 3 is changed in the following order from the curved-course travel speed: fourth emergency travel speed R4, fifth emergency travel speed R5, and sixth emergency travel speed R6, as the obstacle detection distance L5 decreases. As a result, the transport vehicle 3 decelerates and comes to a stop at the sixth emergency travel speed R6. Thus, the control unit H decelerates the transport vehicle 3 based on the detection information from the obstacle sensor 21, as the obstacle sensor 21 detects an obstacle S in the detection area E2.

[0049] Furthermore, in this embodiment, such as Figure 15As shown, when the transport vehicle 3 stops at a predetermined stop position V, the control unit H sets the length of the detection zone E2 along the travel path 1 to the length L4 from the obstacle sensor 21 to the stop position V. That is, the control unit H changes the length of the path length direction X of the detection zone E2 based on the distance to the stop position V. In this embodiment, the length L4 of the detection zone E2 is shorter than the length L1 of the detection zone E2 when the transport vehicle 3 travels at a straight speed. It is set to the length to the front end of the transport vehicle 3 when it is assumed to be stopped at the stop position V, or to a length set forward from the front end of the transport vehicle 3. Here, the stop position V is, for example, set at the transfer position of the item W. The transfer position of the item W is the position of the transport vehicle 3 when transferring the item W between a location that is a transport source or a transport target of the item W. For example, it is the position corresponding to the junction with the processing device, or the position corresponding to the junction with the receiving device, where the processing device processes the item W and the receiving device receives the item W.

[0050] Incidentally, when the transport vehicle 3 is traveling on a curved section 1B, and the shape of the predetermined travel trajectory on the front side is curved, a curved second detection zone EB is set as described above. In this case, because the detection zone E2 is curved, there may be a non-detection zone E3 on the detection line Q that connects a part of the detection zone E2 to the obstacle sensor 21. Therefore, the control unit H takes this situation as a specific situation. When the transport vehicle 3 is traveling at the first travel speed, and this specific situation occurs, and an undetectable zone E4 that cannot detect the obstacle S exists in the detection zone E2 due to the presence of an obstruction U in the non-detection zone E3, the control unit H decelerates the transport vehicle 3 to a second travel speed lower than the first travel speed.

[0051] For example, such as Figure 16As shown, when the transport vehicle 3 travels on the curved section 1B, part or all of the detection area E2 becomes a curved second detection area EB. That is, part or all of the detection area E2 is curved. In this case, there is a specific situation where a non-detection area E3 exists on the detection line Q that connects a part of the detection area E2 to the obstacle sensor 21. Furthermore, there is a case where a partition or other obstruction U is provided in such a non-detection area E3, for example, between a pair of straight sections 1A. When the transport vehicle 3 travels around the curved section 1B, if such an obstruction U exists in the non-detection area E3, the laser for obstacle detection projected by the obstacle sensor 21 is blocked by the obstruction U, and there is a situation where the laser cannot reach the area of ​​the detection area E2, including a part of the front end, and the obstacle S in that area cannot be detected. In this case, the area where the obstacle S cannot be detected becomes the undetectable area E4.

[0052] Thus, in the specific situation described above, where an undetectable zone E4 exists in the detection zone E2 due to the presence of an obstruction U in the non-detection zone E3, preventing the detection of an obstacle S, the control unit H decelerates the transport vehicle 3 to an emergency travel speed (second travel speed) lower than the base travel speed (first travel speed). Furthermore, in this embodiment, the distance along the travel path 1 from the transport vehicle 3 to the undetectable zone E4 is defined as the undetectable distance L6, and the control unit H sets the emergency travel speed so that the emergency travel speed (second travel speed) decreases as the undetectable distance L6 decreases. Additionally, in this embodiment, an emergency travel speed lower than the base travel speed (first travel speed) is equivalent to the second travel speed. That is, when the base travel speed is a straight-line travel speed and an undetectable zone E4 exists, each of the emergency travel speeds from the first emergency travel speed R1 to the sixth emergency travel speed R6 is equivalent to the second travel speed. Furthermore, when the base driving speed is the curve driving speed and an undetectable zone E4 exists, the fourth emergency driving speed R4 to the sixth emergency driving speed R6 are each equivalent to the second driving speed. In this embodiment, the second driving speed and the third driving speed (which decelerates when an obstacle S is detected in the detection zone E2) are not specifically distinguished; both are set to the same speed.

[0053] That is, the control unit H sets an emergency travel speed so that the emergency travel speed decreases as the undetectable distance L6 shortens. For example, when the goods transport vehicle 3 is traveling at a curve travel speed, if an undetectable area E4 exists in the detection area E2, the travel speed of the goods transport vehicle 3 is set and changed in the order of the curve travel speed, the fourth emergency travel speed R4, the fifth emergency travel speed R5, and the sixth emergency travel speed R6 as the undetectable distance L6 shortens. As a result, the travel speed of the goods transport vehicle 3 gradually decreases. Here, if an obstacle S exists in the undetectable area E4, the obstacle sensor 21 detects the obstacle S as the goods transport vehicle 3 is traveling. In this case, the control unit H performs the control described above when the obstacle S is detected, based on the detection information from the obstacle sensor 21, causing the goods transport vehicle 3 to decelerate. On the other hand, when there is no obstacle S in the undetectable zone E4, the undetectable zone E4 decreases as the transport vehicle 3 moves, so the transport vehicle 3 will not reach the sixth emergency travel speed R6 and stop, but will continue to travel. Then, when the undetectable zone E4 is no longer present, the travel speed of the transport vehicle 3 is set back to the curve travel speed, and thus, the transport vehicle 3 accelerates.

[0054] 2. Other implementation methods

[0055] Next, other embodiments of the material conveying equipment will be described.

[0056] (1) In the above embodiment, the detectable region E1 is Figure 5 The structure shown is an example of a region that appears fan-shaped or semi-circular when viewed vertically. However, it is not limited to this structure. For example, the detectable area E1 can also be a shape other than a fan shape, such as a rectangle or triangle when viewed vertically. Furthermore, in the above embodiment, the structure of the detectable area E1 is described as a planar region that can be obtained by rotating the light-projecting part around its longitudinal axis. However, it is not limited to this; for example, in addition to rotating the light-projecting part around its longitudinal axis, it can also be rotated around its horizontal axis, thereby making the detectable area E1 a three-dimensional region.

[0057] (2) In the above embodiment, the structure of the detection area E2 as a strip-shaped region when viewed in the vertical direction was described as an example. However, it is not limited to such a structure. For example, the detection area E2 may also be a shape other than a strip, such as a semi-circle or a triangle when viewed in the vertical direction.

[0058] (3) In the above embodiment, an example was described using a structure where an emergency travel speed is set such that the emergency travel speed (third travel speed) decreases as the obstacle detection distance L5 decreases. However, this structure is not limited to this. For example, the emergency travel speed (third travel speed) when an obstacle S is detected may be only one speed lower than the reference travel speed (first travel speed). Furthermore, the emergency travel speed (third travel speed) in this case may be set to one speed when decelerating from a straight-line travel speed and one speed when decelerating from a curve travel speed. In addition, the emergency travel speed (third travel speed) may also be zero. In this case, the control unit H immediately stops the transport vehicle 3 when the obstacle sensor 21 detects the obstacle S.

[0059] (4) In the above embodiment, an example was described using a structure where the emergency travel speed is set so that the emergency travel speed (second travel speed) decreases as the undetectable distance L6 shortens. However, this structure is not limited to this. For example, the emergency travel speed (second travel speed) in the presence of the undetectable zone E4 may be only one speed lower than the reference travel speed (first travel speed). Furthermore, the emergency travel speed (second travel speed) in this case may be set to one speed when decelerating from the straight-line travel speed and one speed when decelerating from the curve travel speed. In addition, the emergency travel speed (second travel speed) may also be zero. In this case, the control unit H immediately stops the transport vehicle 3 when the undetectable zone E4 is present.

[0060] (5) In the above embodiment, the example described is that the second driving speed, which is the emergency driving speed when the undetectable zone E4 exists, and the third driving speed, which is the emergency driving speed when the obstacle S is detected, are set to the same speed. However, this structure is not limited to this one, and the second and third driving speeds may be set differently. For example, even if the undetectable zone E4 exists, the obstacle S may not actually exist in that undetectable zone E4, so it is appropriate to set the second driving speed to be higher than the third driving speed when the obstacle S is actually detected.

[0061] (6) In the above embodiment, the structure in which the control unit H sets the detection area E2 so that the length of the detection area E2 increases as the speed of the goods transport vehicle 3 increases has been described as an example. However, it is not limited to such a structure. For example, it is also possible to make the control unit H set the length of the detection area E2 to a certain value regardless of the speed of the goods transport vehicle 3.

[0062] (7) In the above embodiment, the structure in which the length of the detection area E2 is set to the length from the obstacle sensor 21 to the stop position V when the transport vehicle 3 is stopped at the predetermined stop position V is described as an example. However, it is not limited to such a structure. For example, even when the transport vehicle 3 is stopped at the predetermined stop position V, the length of the detection area E2 may be set to the same length as when the transport vehicle 3 is not stopped at the predetermined stop position V.

[0063] (8) In the above embodiment, the structure in which the goods transport vehicle 3 travels along the travel track 2 that is suspended and supported from the roof has been described as an example. However, it is not limited to such a structure. For example, it is also possible to make a structure in which the goods transport vehicle 3 travels along the travel track 2 set on the ground. In addition, the goods transport vehicle 3 may also be a trackless vehicle that travels on the ground. Moreover, in the case of a trackless goods transport vehicle 3, it can be made into a structure in which the position of the travel path 1 is fixed, or it can be made into a structure in which the position of the travel path 1 is changed each time.

[0064] (9) Furthermore, the structures disclosed in the above embodiments can be combined with structures disclosed in other embodiments, provided that there is no contradiction. Regarding other structures, the embodiments disclosed in this specification are merely illustrative in all respects. Therefore, various modifications can be made appropriately without departing from the spirit of this disclosure.

[0065] 3. Summary of the above embodiments

[0066] The following is a summary of the article conveying equipment described above.

[0067] The goods conveying equipment includes a goods conveying vehicle that travels along a travel path to convey goods; the goods conveying vehicle includes: an obstacle sensor that detects obstacles existing in a detection area, the detection area being set to match the shape of a predetermined travel trajectory on the front side of the goods conveying vehicle; and a control unit that controls the travel speed of the goods conveying vehicle based on the detection information of the obstacle sensor; sets a non-detection area in the area within the detectable area of ​​the obstacle sensor that deviates from the predetermined travel trajectory, where the obstacle is not detected by the obstacle sensor; defines a specific condition as a situation where the non-detection area exists on the detection line connecting a part of the detection area to the obstacle sensor due to the curvature of the detection area; and when the control unit is driving the goods conveying vehicle at a first travel speed, in the aforementioned specific condition, and in a situation where there is an undetectable area in the detection area where the obstacle cannot be detected due to the presence of an obstruction in the non-detection area, the goods conveying vehicle is decelerated to a second travel speed lower than the aforementioned first travel speed.

[0068] According to this structure, within the detectable area of ​​the obstacle sensor, a detection zone is set with a shape matching the predetermined travel trajectory of the front side of the goods transport vehicle, and a non-detection zone is set in the area deviating from the predetermined travel trajectory where obstacle detection is not performed. Therefore, obstacles existing on the predetermined travel trajectory can be detected by the obstacle sensor, and the goods transport vehicle can be driven appropriately based on the detection results.

[0069] Here, depending on the shape of the predetermined travel trajectory on the front side of the transport vehicle, there may be a curved detection zone. Consequently, there may be a specific situation where a non-detection zone exists on the detection line connecting a portion of the detection zone to the obstacle sensor. In such a situation, if there is an obstruction in the non-detection zone, an undetectable zone may exist within the detection zone due to the presence of that obstruction. If an obstacle exists in such an undetectable zone, the transport vehicle may come into contact with it because it cannot be detected in advance by the obstacle sensor. However, according to this structure, when the transport vehicle is traveling at a first speed, and the aforementioned specific situation occurs, and an undetectable zone exists in the detection zone due to an obstruction in the non-detection zone, the transport vehicle's speed is reduced from the first speed to the second speed regardless of the actual presence or absence of an obstacle in the undetectable zone. Therefore, even if an obstacle exists in the undetectable zone, the transport vehicle can be stopped quickly. That is, the transport vehicle can be appropriately controlled to prevent contact with obstacles.

[0070] Here, preferably, when the aforementioned control unit does not detect the aforementioned obstacle in the aforementioned detection area, it causes the aforementioned goods transport vehicle to travel at the aforementioned first travel speed, and when the aforementioned obstacle is detected in the aforementioned detection area, it causes the aforementioned goods transport vehicle to decelerate to a third travel speed lower than the aforementioned first travel speed.

[0071] According to this structure, when an obstacle is detected in the detection zone, the transport vehicle is decelerated from its first travel speed to its third travel speed. This allows the transport vehicle to stop quickly if there is a possibility of contact with the obstacle, preventing such contact. Conversely, when no obstacle is detected in the detection zone, the transport vehicle continues to travel at its first travel speed without deceleration, allowing it to quickly reach its destination. Furthermore, the third travel speed can be the same as or different from the second travel speed described above.

[0072] Furthermore, it is preferable to use the distance along the aforementioned travel path from the aforementioned goods transport vehicle to the aforementioned obstacle detected in the aforementioned detection area as the obstacle detection distance; the aforementioned control unit sets the aforementioned third travel speed so that the aforementioned third travel speed decreases as the aforementioned obstacle detection distance decreases.

[0073] According to this structure, when an obstacle is detected in the detection zone, the transport vehicle travels at a relatively high speed when the obstacle detection distance is long, preventing the transport vehicle's speed from decreasing to a required level, thus allowing the transport vehicle to reach the destination earlier. Furthermore, since the transport vehicle's speed is sufficiently reduced when the obstacle detection distance is short, the transport vehicle can be brought to a proper stop before contacting the obstacle.

[0074] Furthermore, it is preferable to use the distance along the aforementioned travel path from the aforementioned goods transport vehicle to the aforementioned undetectable area as the undetectable distance; the aforementioned control unit sets the aforementioned second travel speed so that the aforementioned second travel speed decreases as the aforementioned undetectable distance becomes shorter.

[0075] According to this structure, since the transport vehicle travels at a relatively high speed when the undetectable distance is long, it can avoid the transport vehicle's speed from decreasing to a required level, thus making it easier for the transport vehicle to reach the destination earlier. Furthermore, since the transport vehicle's speed is sufficiently reduced when the undetectable distance is short, it can be brought to a proper stop even when obstacles are present in the undetectable area.

[0076] Furthermore, preferably, the aforementioned control unit sets the aforementioned detection area by changing its shape at any time to match the shape of the aforementioned travel path on the front side of the aforementioned goods transport vehicle.

[0077] According to this structure, by changing the shape of the detection area to match the shape of the travel path at any time, obstacles on the travel path in front of the transport vehicle can be detected appropriately, and it is easy to avoid misdetecting objects that exist in areas deviating from the predetermined travel trajectory of the transport vehicle and have no possibility of contact with the transport vehicle as obstacles.

[0078] Furthermore, it is preferable that the aforementioned control unit sets the aforementioned detection zone so that the length of the aforementioned detection zone along the aforementioned travel path increases as the speed of the aforementioned goods transport vehicle increases.

[0079] According to this structure, obstacles can be detected from a greater distance as the travel speed increases. Therefore, it is possible to increase the travel speed of the transport vehicle without the obstacle sensor detecting an obstacle, thereby making it easier for the transport vehicle to reach the destination earlier, while appropriately avoiding contact between the transport vehicle and obstacles.

[0080] Furthermore, it is preferable that when the aforementioned control unit stops the aforementioned goods transport vehicle at a predetermined stop position, the length of the aforementioned detection area along the aforementioned travel path is set to the length from the aforementioned obstacle sensor to the aforementioned stop position.

[0081] When the transport vehicle stops at a designated stop position, even if there is an obstacle ahead of the stop position, there is no possibility of the transport vehicle coming into contact with the obstacle until it restarts from the stop position. According to this structure, when the transport vehicle stops at the designated stop position, since the length of the detection zone along the travel path is set to the length from the obstacle sensor to the stop position, obstacles ahead of the stop position are not detected by the obstacle sensor. Therefore, unnecessary deceleration of the transport vehicle can be avoided, and the transport vehicle can easily reach its destination earlier.

[0082] Industrial availability

[0083] The technology disclosed herein can be used in article conveying equipment that has an article conveying vehicle that travels along a driving path to convey articles.

[0084] Explanation of reference numerals in the attached figures

[0085] 1: Driving route

[0086] 3: Goods transport vehicle

[0087] 21: Obstacle Sensor

[0088] C: Pre-determined driving trajectory

[0089] E1: Detectable area

[0090] E2: Detection Area

[0091] E3: Non-detection area

[0092] E4: Undetectable region

[0093] H: Control Department

[0094] L4: Length

[0095] L5: Obstacle detection distance

[0096] L6: Undetectable distance

[0097] Q: Testing line

[0098] S: Obstacle

[0099] U: Covering

[0100] V: Stop position

[0101] W: Item.

Claims

1. An article transport apparatus provided with an article transport vehicle that travels along a travel path to transport an article, wherein the article transport vehicle is provided with an obstacle sensor that detects an obstacle present in a detection zone set in correspondence with a shape of a predetermined travel trajectory on a front side of the article transport vehicle, and a control section that controls a travel speed of the article transport vehicle based on detection information of the obstacle sensor, characterized in that a non-detection zone in which detection of the obstacle by the obstacle sensor is not performed is set in a region within a detectable zone of the obstacle sensor and deviating from the predetermined travel trajectory, a condition in which the non-detection zone is present on a detection line connecting a portion of the detection zone and the obstacle sensor due to a bend of the detection zone is taken as a specific condition, the control section decelerates the article transport vehicle to a second travel speed lower than a first travel speed at which the article transport vehicle travels in a state in which the specific condition is present and a condition in which a non-detectable zone in which the obstacle cannot be detected in the detection zone due to a presence of an obstruction in the non-detection zone is present, sets the second travel speed so as to be lower as a distance along the travel path from the article transport vehicle to the non-detectable zone becomes shorter.

2. The article transport apparatus according to claim 1, wherein the control section travels the article transport vehicle at the first travel speed in a case in which the obstacle is not detected in the detection zone, and decelerates the article transport vehicle to a third travel speed lower than the first travel speed in a case in which the obstacle is detected in the detection zone.

3. The article transport apparatus according to claim 2, wherein a distance along the travel path from the article transport vehicle to the obstacle detected in the detection zone is taken as an obstacle detection distance, and the control section sets the third travel speed so as to be lower as the obstacle detection distance becomes shorter.

4. The article transport apparatus according to any one of claims 1 to 3, wherein the control section changes the shape of the detection zone in correspondence with a shape of the travel path on the front side of the article transport vehicle in real time to perform the setting of the detection zone.

5. The article transport apparatus according to any one of claims 1 to 3, wherein the control section performs the setting of the detection zone so as to be longer in length along the travel path as the travel speed of the article transport vehicle becomes higher.

6. The article transport apparatus according to claim 4, wherein the control section performs the setting of the detection zone so as to be longer in length along the travel path as the travel speed of the article transport vehicle becomes higher.

7. The article transport apparatus according to any one of claims 1 to 3, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The aforementioned control section sets the length of the aforementioned detection zone along the aforementioned travel path to the length from the aforementioned obstacle sensor to the aforementioned stop position in the case of stopping the aforementioned article transport vehicle at a prescribed stop position.

8. The article transport apparatus according to claim 4, wherein The aforementioned control section sets the length of the aforementioned detection zone along the aforementioned travel path to the length from the aforementioned obstacle sensor to the aforementioned stop position in the case of stopping the aforementioned article transport vehicle at a prescribed stop position.

9. The article transport apparatus according to claim 5, wherein The aforementioned control section sets the length of the aforementioned detection zone along the aforementioned travel path to the length from the aforementioned obstacle sensor to the aforementioned stop position in the case of stopping the aforementioned article transport vehicle at a prescribed stop position.

10. The article transport apparatus according to claim 6, wherein The aforementioned control section sets the length of the aforementioned detection zone along the aforementioned travel path to the length from the aforementioned obstacle sensor to the aforementioned stop position in the case of stopping the aforementioned article transport vehicle at a prescribed stop position.

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