Item transfer device

Abstract

To provide an article transfer device capable of reducing an influence of disturbance on a sensor.SOLUTION: An article movement system 1 includes: a robot hand 15 for gripping a part of an article by inserting a grip claw 30a of a grip unit 30 to an article group X placed in a container 50 and transferring the gripped article to a transfer destination position; a sensor 9 provided above the container 50 to detect an article height in an insertion direction of the grip claw 30a in the article group X placed in the container 50 by irradiating the article group X with light; a control unit 70 for controlling grip operation of the robot hand on the basis of the article height detected by the sensor 9; and a fan 80 for blowing or exhausting air with respect to a space that is below the sensor 9 and is between the sensor 9 and the article group X irradiated with light.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention particularly relates to an article transfer device for gripping and transferring articles.

Background Art

[0002] As described in Patent Document 1, there is known an article gripping system that grips, measures, and discharges articles from a group of articles stored in a container. In this system, the control unit positions the container below the gripping unit and then raises the container. The raising of the container stops at a certain timing. The gripping claws of the gripping unit have entered the group of articles in the stopped container. The control unit switches the gripping claws to the closed state and causes the gripping claws to grip the articles. Then the container is lowered and moved horizontally. During this time, the weight of the articles gripped by the gripping unit is measured. When predetermined conditions are satisfied, the control unit releases the gripping of the articles by the gripping claws and discharges the articles to the lower discharge chute.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the system as described above, the group of articles is placed on a placement portion such as a container. The placement portion is relatively moved with respect to the gripping unit, and the gripping claws of the gripping unit enter the group of articles. The insertion amount of the gripping claws affects the amount of articles gripped by the gripping unit, and thus is important in the control of the system.

[0005] The present invention Detect the height of a group of objects. aims to provide an article transfer device that can

Means for Solving the Problems

[0006] An article transfer device according to one aspect of the present invention includes a robot hand having at least one gripping part for gripping articles, which inserts the gripping member of the gripping part into a group of articles placed on a mounting section to grip a part of the articles and transfers the gripped articles to a destination position; a sensor provided above the mounting section that detects the height of the articles in the insertion direction of the gripping member in the group of articles placed on the mounting section by irradiating the group of articles with light; and a control unit that controls the gripping operation of the robot hand based on the article height detected by the sensor. ,of Prepare. With this item transfer device, the height of the item is detected by a sensor. Based on this detection result, the gripping motion of the robot hand is controlled to grip the desired amount of item.

[0007] The article transfer device may further include a fan located below the sensor that blows or exhausts air into the space between the sensor and the group of articles being illuminated. This item transfer device uses a fan to blow or exhaust air into the space below the sensor, between the sensor and the group of items being illuminated. Even if steam or parts of the items are present in the group, the blowing or exhausting air can remove or reduce the steam or parts of the items from the space. Neither the blowing nor the exhausting air affects the sensor's detection operation due to light illumination (or if it does, it is only slightly and negligible). Therefore, the influence of disturbances on the sensor can be reduced.

[0008] At least one gripping section is comprised of multiple gripping sections, and the article transfer device further includes a weight calculation unit that calculates the weight (mass) of the article gripped by each of the multiple gripping sections. The control unit controls the gripping sections, performs combination calculations based on the calculation results from the weight calculation unit, selects a combination of gripping sections that results in a preset target weight value, and may discharge the article to the selected gripping section. In this case, the article height is accurately detected by the sensor, and the control unit can accurately control the insertion amount of the gripping members into the group of articles when performing combination weighing. Therefore, the weighing accuracy and efficiency of combination weighing are improved.

[0009] The control unit controls the fan's operation to blow or exhaust air into the space and to stop it, and may blow or exhaust air into the space at times other than the weight calculation period during which the weight calculation unit calculates the weight of the item. If airflow hits an item held by the gripping member, the weight calculation of the item may be affected. With the above configuration, the influence of blowing or exhausting air on the weight calculation of the item can be reduced.

[0010] The space where air is blown or exhausted by the fan may be a space that avoids the position of the robot hand. If airflow hits an item grasped by the robot hand, it may affect the quality or weight of the item being transferred. The above configuration can reduce such effects. [Effects of the Invention]

[0011] According to the present invention, The height of the object is detected by a sensor. Based on this detection result, the gripping motion of the robot hand is controlled to grip the object to the desired amount. . [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a front view of an article moving system according to one embodiment of the present disclosure. [Figure 2] Figure 2 is a schematic perspective view showing multiple gripping parts. [Figure 3] Figure 3 is a block diagram of the item movement system. [Figure 4] Figure 4 is a plan cross-sectional view showing the arrangement of multiple gripping parts, mounting parts, and sensors. [Figure 5] Figure 5 is a perspective view showing an example of the fan installation shown in Figure 1. [Figure 6] Figure 6 is a perspective view showing another example of the fan installation shown in Figure 1. [Figure 7] Figure 7 is a front view of an article transfer system according to another embodiment of the present disclosure. [Modes for carrying out the invention]

[0013] Embodiments of this disclosure will be described below with reference to the drawings. In the description of the drawings, the same elements will be denoted by the same reference numerals, and redundant descriptions will be omitted.

[0014] First, with reference to Figures 1 and 2, the article transfer system (article transfer device) 1 according to this embodiment will be described. The article transfer system 1 shown in Figure 1 is a system that removes and moves some articles from a group of articles X contained in a container 50. The article transfer system 1 removes some articles from the container 50 and discharges them to the outside so that the weight (mass) of some articles falls within a target weight range. In other words, the article transfer system 1 is a weighing system that moves articles of a predetermined target weight from a group of articles X. The articles discharged by the article transfer system 1 are, for example, packaged in bags or placed in other containers in a subsequent process of the article transfer system 1 and shipped as products. The articles are, for example, noodles such as spaghetti, or foods containing a lot of sugar. The articles may also be foods with high viscosity. The articles may be foods that are heated and contained in the container 50, generating steam, etc. Alternatively, the articles may be lightweight, fine, and easily blown away foods.

[0015] The item moving system 1 includes a weighing device 120 for weighing items. The weighing device 120 includes two robot hands (gripping units) 15, each having a plurality of gripping parts 30; two hand drive units 10 for moving the robot hands 15 horizontally; a container (placement part) 50 on which the group of items X is placed; and a container drive unit 54 for moving the container 50 vertically and horizontally, respectively. The item moving system 1 also includes a control unit 70 that controls each part of the robot hands 15, the hand drive units 10, and the container drive units 54, respectively. The robot hands 15, the hand drive units 10, and the container drive units 54 are attached to, for example, a rectangular parallelepiped main frame 121 of the weighing device 120.

[0016] In the article transfer system 1, for example, a pair of robot hands 15 with the same configuration are arranged side by side horizontally. In the following description, the robot hand 15 arranged on the left side in the front view of FIG. 1 may be referred to as the first robot hand 15A, and the robot hand 15 arranged on the right side in the front view may be referred to as the second robot hand 15B. However, when describing the common configuration and functions, the name "robot hand 15" is simply used.

[0017] In the robot hand 15, for example, four gripping parts 30 arranged side by side in the left-right direction are arranged in four rows in the front-back direction (the direction perpendicular to the plane of FIG. 1). Thus, if the number of gripping parts 30 arranged side by side in the left-right direction is M, and the number of gripping parts 30 arranged in the front-back direction is N (both M and N are natural numbers), the robot hand 15 has a configuration in which (M×N) gripping parts 30 are arranged at the lattice point positions. In this embodiment, each robot hand 15 has 16 gripping parts 30. Depending on the shape of the container 50, the type of article, etc., the arrangement of the gripping parts 30 in the robot hand 15 may be appropriately changed. Both M and N or either one of them may be a natural number other than 4.

[0018] As shown in FIG. 2, each gripping part 30 has, for example, a plurality of gripping claws (gripping members) 30a, and grips an article by closing the gripping claws 30a. Each gripping part 30 includes a gripping member drive mechanism 30b that drives the plurality of gripping claws 30a. The gripping member drive mechanism 30b drives the gripping claws 30a using, for example, a motor or fluid pressure as a drive source. The mechanism for gripping an article by opening and closing the gripping claws 30a will be described later.

[0019] The robot hand 15 has a plurality of weighing devices 40 for weighing the weight of the item gripped by each gripping part 30. That is, 16 weighing devices 40 are provided for 16 ((M × N)) gripping parts 30. The robot hand 15 has, for example, a single plate-shaped connecting member 16. Each gripping part 30 and each weighing device 40 are assembled integrally via a connecting part 40a. The top surface of each weighing device 40 is fixed to the connecting member 16 via a mounting bracket 400. Each gripping part 30 is fixed to the bottom surface of each weighing device 40.

[0020] Each measuring instrument 40 includes a sensor unit and an internal control unit housed within the casing of the measuring instrument 40 (neither of which are shown). The sensor unit includes, for example, a force sensor and an acceleration sensor. For example, a strain gauge type load cell is used as the force sensor. For example, a strain gauge type load cell or a MEMS type miniature acceleration sensor is used as the acceleration sensor.

[0021] In the item movement system 1, for example, two hand drive units 10 having the same configuration are provided, each corresponding to the first robot hand 15A and the second robot hand 15B. In the following description, the hand drive unit 10 located on the left side in the front view of Figure 1 and moving the first robot hand 15A may be referred to as the first hand drive unit 10A, and the hand drive unit 10 located on the right side in the front view and moving the second robot hand 15B may be referred to as the second hand drive unit 10B. However, when describing common configurations and functions, the name "hand drive unit 10" is simply used.

[0022] In the entire system, including the first robot hand 15A and the second robot hand 15B, eight gripping parts 30 are arranged in the left-right direction and four rows in the front-back direction. In other words, the weighing device 120 has a total of 32 gripping parts 30 (4 x 2 units (one pair) x 4 rows = (generalized to (M x 2 x N) parts)).

[0023] The hand drive unit 10 has two parallel frames 12 and a forward / backward movement mechanism 11 that moves the robot hand 15 horizontally along the frames 12. The hand drive unit 10 can move the block 111 that holds the robot hand 15 forward or backward using the forward / backward movement mechanism 11. The hand drive unit 10 has, for example, a servo motor, an air cylinder, etc., for moving the block 111. The connecting member 16 described above is connected to the block 111, for example, by screw fastening.

[0024] In the item movement system 1, the first hand drive unit 10A moves the first robot hand 15A in the forward / backward direction (horizontally), and the second hand drive unit 10B moves the second robot hand 15B in the forward / backward direction (horizontally). This makes it possible to match the position of the group of items X in the container 50 with the item gripping position set in each robot hand 15. Note that in the weighing device 120, the hand drive unit 10 or the forward / backward movement mechanism 11 may be omitted.

[0025] The internal control unit of the weighing device 40 measures the weight of the item being gripped by the gripping unit 30 based on the force measured by the sensor unit. The weighing device 40 is not limited to a method that measures the weight of the item based on the force measured when the gripping unit 30 is moving. The weighing device 40 may also measure the weight of the item being gripped by the gripping unit 30 in a stationary state using a load cell or the like. The internal control unit of the weighing device 40 may also measure the weight of the item by dividing the force measured by the force sensor by the acceleration measured by the acceleration sensor. Each weighing device 40 is a weight calculation unit that calculates the weight of the item gripped by the gripping claws 30a of each gripping unit 30.

[0026] The container 50 is a component on which the group of articles X is placed. The container 50 is held or placed on a holding unit 52 that moves horizontally and vertically. The container 50 is movable between a first position P1 located below the first robot hand 15A and a second position P2 located below the second robot hand 15B, for example, by a container drive unit 54. The first position P1 and the second position P2 are separated in the left-right direction, and the area occupied by the container 50 at the first position P1 and the area occupied by the container 50 at the second position P2 do not overlap. The container 50 is a rectangular parallelepiped container that is open upwards. In a plan view, the container 50 is slightly larger than the area in which the multiple gripping units 30 are arranged. In a plan view, the container 50 has a shape and size that can enclose the multiple gripping units 30. The container 50 has a shape and size that corresponds exactly to one robot hand 15.

[0027] When the container 50 is in the first position P1, moving the container 50 upwards brings it closer to the gripping part 30 of the first robot hand 15A, allowing the gripping part 30 to grasp an item from the group of items X inside the container 50. At this time, the gripping part 30 of the second robot hand 15B cannot grasp an item from the group of items X inside the container 50. Similarly, when the container 50 is in the second position P2, moving the container 50 upwards brings it closer to the gripping part 30 of the second robot hand 15B, allowing the gripping part 30 to grasp an item from the group of items X inside the container 50. At this time, the gripping part 30 of the first robot hand 15A cannot grasp an item from the group of items X inside the container 50.

[0028] When the amount of articles X contained inside container 50 decreases, the container 50 with the reduced amount of articles X inside is replaced by a person or machine with a new container 50 (containing a larger amount of articles X). Alternatively, instead of replacing container 50, the article transfer system 1 may be equipped with an article supply mechanism for supplying articles to container 50.

[0029] The container drive unit 54 moves the container 50 vertically and horizontally using a motor and fluid pressure as drive sources. The container drive unit 54 has a drive box 55 fixed to a frame (not shown) adjacent to the weighing device 120, a first main arm section 56A and a second main arm section 56B which are pivotable around two parallel first axes L1 and second axis L2 provided on the drive box 55, and a first sub-arm section 57A and a second sub-arm section 57B which are rotatably connected to the tip of the first main arm section 56A and the tip of the second main arm section 56B, respectively. The drive box 55 is fixed to another frame 200 (see Figure 5) adjacent to the rear of the frame to which the robot hand 15 is attached. The first axis L1 and the second axis L2 extend in the front-rear direction (perpendicular to the plane of the paper in Figure 1 and horizontally). The tip of the first sub-arm portion 57A and the tip of the second sub-arm portion 57B are rotatably connected to the rear end of the holding portion 52. The holding portion 52 is supported by these link mechanisms.

[0030] The first main arm section 56A and the second main arm section 56B are each oscillated to face any direction by separate motors housed in the drive box 55. The pivot axes of the first sub-arm section 57A and the second sub-arm section 57B with respect to the first main arm section 56A and the second main arm section 56B are parallel to the first axis L1 and the second axis L2. For example, the rotation angle of the second sub-arm section 57B with respect to the second main arm section 56B is adjustable. The pivot axes of the first sub-arm section 57A and the second sub-arm section 57B with respect to the holding section 52 are also parallel to the first axis L1 and the second axis L2. With the positions of the first axis L1 and the second axis L2 as fixed points, the first main arm section 56A, the first sub-arm section 57A, the second main arm section 56B, the second sub-arm section 57B, and the holding section 52 constitute five sides of a hexagon. The container drive unit 54 has a two-axis parallel link mechanism due to these configurations. The container drive unit 54 moves the holding unit 52 in the vertical and horizontal directions by rotating each arm portion under the control of the control unit 70. The orientation of the holding unit 52 is maintained horizontally by the rod 58.

[0031] Under the control of the control unit 70, the holding unit 52 can move while maintaining a horizontal posture to a first position P1, a position closer to the first robot hand 15A than the first position P1, a second position P2, and a position closer to the second robot hand 15B than the second position P2. This allows for adjustment of the relative position of the container 50 with respect to the first robot hand 15A and the relative position of the container 50 with respect to the second robot hand 15B. The configuration is not limited to the above, and the container drive unit 54 may have a left-right movement mechanism for moving the holding unit 52 in the left-right direction and a vertical movement mechanism for moving the holding unit 52 in the vertical direction. The position of the container 50 can also be adjusted with such a two-axis drive mechanism.

[0032] The container drive unit 54 raises the holding unit 52 and the container 50, bringing the container 50 and the group of articles X closer to the robot hand 15. By lowering the holding unit 52 and the container 50, the container 50 and the group of articles X are separated from the robot hand 15. The container drive unit 54 inserts the gripping claws 30a into the group of articles X contained (placed) in the container 50, and then separates the gripping claws 30a that have gripped the articles from the container 50. In other words, the first robot hand 15A and the second robot hand 15B insert the gripping claws 30a of their respective gripping units 30 into the group of articles X inside the container 50 and grip a portion of the articles.

[0033] The item transfer system 1 is equipped with two discharge chutes 60. For example, two discharge chutes 60 of the same size and shape are arranged side by side on the left and right. In the following description, the discharge chute 60 located on the left side in the front view of Figure 1 may be referred to as the first discharge chute 60A, and the discharge chute 60 located on the right side in the front view may be referred to as the second discharge chute 60B. However, when describing common configurations and functions, the name "discharge chute 60" is simply used.

[0034] The discharge chute 60 is a funnel-shaped component. The discharge chute 60 is positioned below the robot hand 15. Specifically, the first discharge chute 60A is positioned below the first robot hand 15A, and the second discharge chute 60B is positioned below the second robot hand 15B. The first position P1 of the container 50 is located between the first robot hand 15A and the first discharge chute 60A, and the second position P2 of the container 50 is located between the second robot hand 15B and the second discharge chute 60B.

[0035] The first discharge chute 60A receives the article dropped by the gripping portion 30 of the first robot hand 15A when the container 50 is in the second position P2, and discharges it to the outside of the article transfer system 1. Similarly, the second discharge chute 60B receives the article dropped by the gripping portion 30 of the second robot hand 15B when the container 50 is in the first position P1, and discharges it to the outside of the article transfer system 1. In this way, the first robot hand 15A and the second robot hand 15B transfer the article gripped by their respective gripping portions 30 to the destination position. That is, in this specification, "release of grip" by each robot hand 15 and the resulting "drop of article" mean the transfer of the article to the discharge chute 60.

[0036] In this embodiment, two discharge chutes are used, but the invention is not limited to this, and the first robot hand 15A and the second robot hand 15B may share one discharge chute. In that case, the upper opening of the one discharge chute is set to be the size and position that encompasses the entirety of the first position P1 and the second position P2 in a plan view. Alternatively, the items that fall from the robot hand 15 may be discharged directly to the outside without using a discharge chute.

[0037] Figure 2 is a block diagram of the item moving system 1. In Figure 2, the control unit 70 controls the operation of various components of the item moving system 1, such as the gripping member drive mechanism 30b and the container drive unit 54. The control unit 70 performs combination calculations using the weight values ​​of the items weighed by the weighing scale 40. The control unit 70 is configured as a computer device including a processor such as a CPU, memory such as ROM and RAM, storage, and communication devices. The control unit 70 is electrically (or communicatively) connected to the hand drive unit 10, the gripping member drive mechanism 30b, the weighing scale 40, and the container drive unit 54. Ideal weight values ​​and the like are input to the control unit 70 via the operation panel 100.

[0038] The control unit 70 controls the operation of various components of the article moving system 1, such as the hand drive unit 10, the gripping member drive mechanism 30b, and the container drive unit 54, by executing a program stored in memory by the CPU, and also performs combination calculations using the weight values ​​of the articles weighed by the weighing scale 40. The various functions of the control unit 70 do not necessarily have to be implemented in software, they may be implemented in hardware, or they may be implemented through the cooperation of hardware and software.

[0039] The control unit 70 moves the hand drive unit 10 and the container 50, bringing the gripping unit 30 and the container 50 closer together. The control unit 70 controls the gripping member drive mechanism 30b to cause some of the articles of the article group X placed in the container 50 to be gripped by the gripping claws 30a of each gripping unit 30.

[0040] Each weighing device 40 weighs the weight of the item gripped by the corresponding gripping unit 30. The weight of the item gripped by each gripping unit 30 is acquired by the control unit 70. The control unit 70 performs a combination calculation based on the weight of the item gripped by the gripping unit 30. The combination calculation is the process of finding a combination of weight values ​​in which the sum of the weights of the items gripped by each gripping unit 30 equals the target weight. First, the control unit 70 acquires each weight value. Next, based on the result of the combination calculation, the control unit 70 selects the gripping claw 30a of the gripping unit 30 corresponding to the combination of weight values ​​that equals the target weight, and performs control to release the grip of the selected gripping unit 30. At this time, the control unit 70 releases the grip of the item from the gripping unit 30 above the discharge chute 60, causing the item to fall into the discharge chute 60. The item with the target weight is then discharged from the discharge chute 60. If it is impossible to find a combination of weight values ​​that results in the target weight, and the control unit 70 finds a gripping claw 30a of a gripping unit 30 that corresponds to a combination of weight values ​​near the target weight, the control unit 70 selects the gripping unit 30 corresponding to that combination and performs control to release the grip of the selected gripping unit 30. This control is performed, for example, using the weight values ​​of gripping units 30 other than the gripping unit 30 that corresponds to the combination of weight values ​​that results in the target weight.

[0041] The target weight value is a predetermined weight range that includes the target weight value (target weight value, or ideal weight value). For example, the lower limit of the target weight value is 90% or 95% of the target weight value, and the upper limit of the target weight value is 110% or 105% of the target weight value. The vicinity of the target weight value may also be, for example, 90% or more but less than 100% of the lower limit, or 95% or more but less than 100% of the lower limit, or greater than 100% but 110% or less of the upper limit, or greater than 100% but 105% or less of the upper limit.

[0042] As described above, in the article transfer system 1 of this embodiment, the control unit 70 controls the gripping member drive mechanism 30b (gripping section 30) and the container drive unit 54, performs combination calculations based on the calculation results of the weighing instrument 40, and selects a combination of gripping sections 30 that results in a preset target weight value. The control unit 70 then discharges the articles into the selected plurality of gripping sections 30.

[0043] As shown in Figures 1, 3, and 4, a plurality of sensors 9 are provided above the movable area of ​​the holding portion 52, arranged in the front-to-back direction (perpendicular to the plane of the paper in Figure 1). In this embodiment, four sensors 9 are attached, corresponding to the number of rows (N above, specifically 4 rows) of the gripping portion 30 in that direction. The four sensors 9 are fixed to the main body frame 121, for example, and emit light vertically downwards while detecting the reflected light reflected from the surface of the group of articles X. As a result, each sensor 9 detects the height of the articles (height of the group of articles X) in the insertion direction (up and down direction) of the gripping claws 30a within the group of articles X in the container 50.

[0044] As shown in Figures 1 and 4, each sensor 9 transmits and receives light at the central position between the first robot hand 15A and the second robot hand 15B. Each sensor 9 detects the position and number of gripping parts 30 in the left-right direction (M above, specifically 4), and the height of the item, as the holding part 52 and the container 50 are moved between the first position P1 and the second position P2 by the container drive unit 54. The timing of detection may be adjusted by the control unit 70 (for example, to synchronize with the movement of the container drive unit 54) taking into account the left-right movement speed of the container drive unit 54. As a result, each time the container 50 moves (passes through) from the first position P1 to the second position P2, or from the second position P2 to the first position P1, height detection signals are output for 16 points (multiple points corresponding to the planar arrangement of the multiple gripping parts 30) that are distributed in a grid pattern in the left-right direction (direction of movement) and front-back direction within the container 50. In other words, the sensor 9 is located above the container 50 and detects the height of the items in the group of items X in the direction into which the gripping claws 30a are inserted by irradiating the group of items X with light.

[0045] The control unit 70 is electrically (or communicatively) connected to a plurality of sensors 9. Based on the detection results of each sensor 9, the control unit 70 calculates the insertion amount and opening angle of the gripping claws 30a for each gripping unit 30 relative to the group of articles X. The height of the articles varies in each part of the container 50. On the other hand, the container 50 (holding unit 52) ​​is brought close to the robot hand 15 while maintaining a horizontal posture. Therefore, the insertion amount of the gripping claws 30a for each gripping unit 30 relative to the container 50 at a certain height is not constant (uniform).

[0046] The control unit 70 stores, for example, the correspondence between the insertion amount and the opening angle for gripping an item of a desired gripping amount. When the control unit 70 receives height detection signals from each sensor 9, it sets the vertical position of the container 50 and the group of items X, and calculates the corresponding insertion amount for each gripping part 30. The control unit 70 further refers to the stored correspondence and calculates the opening angle of the gripping claws 30a corresponding to the insertion amount for each gripping part 30. The control unit 70 controls the gripping operation of either the first robot hand 15A or the second robot hand 15B (whichever one is to grip the item) so that the calculated insertion amount and opening angle are achieved. In other words, the control unit 70 controls the gripping operation of the robot hand 15 based on the height of the item detected by the sensor 9.

[0047] Returning to Figure 1, the item moving system 1 includes a mechanism to reduce the influence of disturbances such as steam, for example, when dealing with items that generate steam. As shown in Figure 1, the item moving system 1 includes a fan 80 that blows air into the weighing device 120. The fan 80 is located, for example, behind the sensor 9. The configuration of the fan 80 is not particularly limited, and a known blower can be used. The fan 80 has, for example, a motor built into the casing and an impeller attached to the casing. Power is supplied to the fan 80. The control unit 70 is electrically (or communicatively) connected to the fan 80.

[0048] In addition to steam generated from heated objects, other potential disturbances for sensor 9 include food particles that easily become airborne (for example, food containing shredded kelp, dried bonito flakes, or seaweed). If the object is not food, other disturbances may be targeted.

[0049] The fan 80 is installed so as to be slightly tilted downward with respect to the horizontal direction. The fan 80 blows air into the space S (see Figure 4) below the sensor 9 and between the sensor 9 and the group of articles X inside the container 50 that are illuminated by light. This space S overlaps with the illumination space illuminated by light from the sensor 9. That is, as shown in Figure 4, space S is located between the first position P1 and the second position P2 in a plan view.

[0050] Referring to Figure 5, the fan 80 will be described from a different perspective. As shown in Figure 5, the fan 80 is mounted, for example, on another frame 200 adjacent to the weighing device 120. The fan 80 is directed, for example, diagonally downward and supplies a predetermined strength (amount) of wind (airflow) towards space S. The space S through which the fan 80 blows air is the space between the first gripping region RA, which includes the area of ​​the first robot hand 15A, and the second gripping region RB, which includes the area of ​​the second robot hand 15B. In other words, the space through which the fan 80 blows air is the space that avoids the positions of the first robot hand 15A and the second robot hand 15B.

[0051] The control unit 70 controls the operation and stopping of the fan 80 in relation to the space S. In particular, the control unit 70 blows air into the space S at times other than the weight calculation period in which the weight of the item is calculated in the weighing instrument 40. More specifically, the control unit 70 controls the fan 80 to blow air into the space S while the height of the item is detected by the sensor 9. More specifically, the control unit 70 may drive the fan 80 to include the period in which the height of the item is detected by the sensor 9, or it may drive the fan 80 only during the period in which the height of the item is detected by the sensor 9. Alternatively, the control unit 70 may drive the fan 80 to include, or only during, the period in which the container 50 moves (passes) from the first position P1 to the second position P2, or from the second position P2 to the first position P1. This is to prevent the airflow from the fan 80 from hitting the item that is being held by the gripping claws 30a and affecting the weighing process.

[0052] According to the article movement system 1 of this embodiment, the fan 80 blows air into the space S below the sensor 9, between the sensor 9 and the group of articles X that are irradiated with light. Even if steam or parts of the articles are generated from the group of articles X, the airflow can remove or reduce the steam or parts of the articles from the space S. The airflow does not affect the detection operation of the sensor 9 due to light irradiation (or if it does, the effect is slight and negligible). Therefore, the influence of disturbances on the sensor 9 can be reduced.

[0053] Conventionally, if no countermeasures were taken against disturbances that may occur on the group of items X, for example, the sensor 9 could misdetect the height of the items. The control unit 70 controls the height of the container 50 by, for example, calculating the average of the 16 detection results (detected values) described above. If a detection result higher than the actual height of the items is output, the position of the container 50 raised by the container drive unit 54 will be too low, which may result in insufficient insertion of the gripping claws 30a (or even a miss). If a detection result lower than the actual height of the items is output, the position of the container 50 raised by the container drive unit 54 will be too high, which may result in excessive insertion of the gripping claws 30a. According to this embodiment, such problems can be avoided.

[0054] When combined weighing is performed, the height of the items is accurately detected by the sensor 9. The control unit 70 can accurately control the insertion amount of the gripping claws 30a for the group of items X when performing combined weighing. Therefore, the weighing accuracy and efficiency of combined weighing are improved.

[0055] If an airflow hits an item gripped by the gripping claw 30a, the calculation of the item's weight may be affected. By configuring the system to blow air into the space at times other than the weight calculation period, the influence of the airflow on the calculation of the item's weight can be reduced.

[0056] If airflow hits an item held by the robot hand 15, it may affect the quality or weight of the item being transferred. Such effects can be reduced by blowing air into the space S that avoids the robot hand 15.

[0057] The fan 80 is mounted on a separate frame 200 outside the weighing device 120. By blowing air from a position as far away as possible from the space S, the influence of external disturbances can be reliably eliminated. In this case, the timing of the air blowing can be limited to reduce the influence on the gripping and weighing operations. For example, the control unit 70 may blow air only when the container 50 is passing below the sensor 9.

[0058] Although embodiments of the present disclosure have been described above, the present invention is not limited to the above embodiments. For example, in the above embodiments, an example was given in which the robot hand 15 grasps an article by moving the container 50 (holding part 52) ​​closer to the robot hand 15. However, in a different configuration, the robot hand 15 or the gripping part 30 may be moved (for example, downward) closer to the container 50 to grasp an article. In that case, the robot hand 15 or the gripping part 30 is provided with an appropriate known moving mechanism. By moving the robot hand 15 or the gripping part 30 (for example, upward), the gripping claws 30a that are gripping the article can be separated from the container 50.

[0059] The transfer of items by a robot hand is not limited to "releasing the grip" and the resulting "dropping of the item into the discharge chute." The robot hand, while gripping an item, may move horizontally or vertically to transfer the item to another container, another hopper, or a conveying device such as a conveyor.

[0060] The robot hand may have only one gripping part. The sensor for detecting the height of the object group X may be omitted.

[0061] The item transfer system does not need to perform combined weighing. In the item transfer system, a weight calculation unit that calculates the weight of an item gripped by a gripping unit is not provided, and the weight of the item may be calculated after it has been transferred.

[0062] The fan may be a fan that exhausts (or draws in) air into space S, rather than a fan 80 that blows air into space S. A known exhaust fan or suction fan having a motor and an impeller may be used. The same effect as described above can be obtained by exhausting air from the space S between the sensor 9 and the container 50 (group of articles X) to which light from the sensor 9 is irradiated. Alternatively, the fan may be capable of both blowing and exhausting air. The fan may perform blowing and exhausting air, for example, in alternating combinations.

[0063] As shown in Figure 6, the fan 80 may be attached to the main frame 121 of the weighing device 120. In this case as well, the fan 80 is positioned behind the sensor 9. Compared to the above embodiment, by blowing or exhausting air from a position closer to the space S, the target space can be narrowed, and the impact on the gripping and weighing operations can be further reduced.

[0064] The fan may be mounted horizontally and blow or exhaust air horizontally. Alternatively, the fan may blow or exhaust air diagonally upwards. A fan installed at a lower position (approximately the same position as the container 50 that moves left and right) may blow or exhaust air upwards.

[0065] Furthermore, the configuration in which the fan 80 is positioned behind the sensor 9 is not limited. For example, as shown in Figure 7, a weighing device 120A (article moving system 1A) may be employed in which fans 80A and 80B, capable of switching between blowing and exhausting air, are provided on the right and left sides of the main frame 121, respectively. These fans 80A and 80B may be fixed, for example, to the left and right doors (not shown) attached to the main frame 121. At least one fan 80A and 80B are fixed to the inner surface of each door. The fans 80A and 80B are, for example, oriented horizontally and facing each other. The left fan 80A is provided to the left (outside horizontally) of the first gripping area RA, and the right fan 80B is provided to the right (outside horizontally) of the second gripping area RB. That is, the positions of the fans 80A and 80B are outside the first gripping area RA and the second gripping area RB. Fans 80A and 80B are positioned in the center of the first gripping area RA and the second gripping area RB in the front-rear direction.

[0066] The control unit 70 controls the right fan 80B to blow air and the left fan 80A to exhaust air while the container 50 is moving from the first position P1 to the second position P2 (while it is moving to the right). The control unit 70 controls the left fan 80A to blow air and the right fan 80B to exhaust air while the container 50 is moving from the second position P2 to the first position P1 (while it is moving to the left). In other words, in control using a pair of left and right fans, air is blown by the fan located in front of the moving container 50 (the fan facing the approaching container 50), and exhaust is performed by the fan located behind the moving container 50.

[0067] In this case, the space in which air is blown and exhausted by fans 80A and 80B includes the first gripping area RA and the second gripping area RB. Fans 80A and 80B blow and exhaust air across the first gripping area RA and the second gripping area RB. However, even in this case, the control unit 70 blows and exhausts air at times other than the weight calculation period in which the weight of the item is calculated in the weighing instrument 40. The control unit 70 may drive fans 80A and 80B to include the period in which the height of the item is detected by the sensor 9, or it may drive fans 80A and 80B only during the period in which the height of the item is detected by the sensor 9. The driving timing of fans 80A and 80B can be determined in the same way as the driving timing of fan 80 in the above embodiment. With the item moving system 1A, which combines blowing and exhausting air according to the direction of movement of the container 50, the influence of disturbances on the sensor 9 can be suitably reduced, similar to the item moving system 1.

[0068] The timing of the fan's blowing or exhausting may coincide with the weight calculation period in the weighing instrument 40 (weight calculation unit). The space S in which the fan blows or exhausts air may coincide with the position of the robot hand 15, i.e., either the first gripping area RA or the second gripping area RB. [Explanation of symbols]

[0069] 1,1A...Article transfer system (article transfer device), 9...Sensor, 10...Hand drive unit, 15...Robot hand, 15A...First robot hand, 15B...Second robot hand, 30...Gripping unit, 30a...Gripping claw (gripping member), 40...Weighing device (weight calculation unit), 50...Container (placement unit), 52...Holding unit, 54...Container drive unit, 60...Discharge chute, 70...Control unit, 80...Fan, RA...First gripping area, RB...Second gripping area, S...Space, X...Group of articles.

Claims

1. A robot hand having at least one gripping portion for gripping articles, inserting the gripping member of the gripping portion into a group of articles placed on a mounting portion to grip a portion of the articles, and transferring the gripped articles to a destination position, A sensor is provided above the aforementioned mounting section and detects the height of the articles in the direction into which the gripping member is inserted, by irradiating the group of articles with light, A control unit controls the gripping operation of the robot hand based on the height of the item detected by the sensor, A fan located below the sensor and used to blow or exhaust air into the space between the sensor and the group of articles to which the light is irradiated, Equipped with, The control unit controls the blowing or exhausting of air into the space and stopping the fan, and blows or exhausts air into the space at times other than the weight calculation period during which the weight of the article is calculated in the weight calculation unit, in an article transfer device.

2. A robot hand having at least one gripping portion for gripping articles, inserting the gripping member of the gripping portion into a group of articles placed on a mounting portion to grip a part of the articles, and transferring the gripped articles to a transfer destination position, A sensor is provided above the aforementioned mounting section and detects the height of the articles in the direction into which the gripping member is inserted, by irradiating the group of articles with light, A control unit controls the gripping operation of the robot hand based on the height of the item detected by the sensor, A fan located below the sensor and used to blow or exhaust air into the space between the sensor and the group of articles to which the light is irradiated, Equipped with, An article transfer device in which the space where air is blown or exhausted by the fan is a space that avoids the position of the robot hand.

3. The aforementioned at least one gripping portion is a plurality of gripping portions, The system further comprises a weight calculation unit that calculates the weight of the article gripped by each of the gripping members of the plurality of gripping units, The article transfer device according to claim 1, wherein the control unit controls the gripping unit, performs combination calculations based on the calculation results in the weight calculation unit, selects a combination of the gripping units that results in a preset target weight value, and discharges the article to the selected gripping unit.

4. The at least one gripping portion is a plurality of gripping portions, The system further includes a weight calculation unit that calculates the weight of the article gripped by each of the gripping members of the plurality of gripping units. The article transfer device according to claim 2, wherein the control unit controls the gripping unit, performs combination calculations based on the calculation results in the weight calculation unit, selects a combination of the gripping units that results in a preset target weight value, and discharges the article to the selected gripping unit.

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