Cargo handling apparatus and method

According to one embodiment, a cargo handling apparatus includes a first mechanism, a second mechanism, a holding unit, a third mechanism, a fourth mechanism and a conveyor. The first mechanism is movable in a first direction. The second mechanism is connected to the first mechanism and is movable on a first horizontal plane intersecting the first direction. The holding unit is connected to the second mechanism and holds an object to be picked up. The third mechanism is arranged below the first mechanism, the second mechanism and the holding unit, and is movable in the first direction. The fourth mechanism is connected to the third mechanism and is movable on a second horizontal plane opposed to the first horizontal plane. The conveyor is connected to the fourth mechanism, and loads and conveys the object held by the holding unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2014-111729, filed May 29, 2014, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a cargo handling apparatus and method.

BACKGROUND

Due to the globalization of supply chains and the aging of the working population, there has been a trend of shortages in the labor force for handling the increased volume of physical distribution. Therefore, Cartesian robots and articulated-arm robots have been popularized to achieve high-speed and effective cargo handling operations, such as picking of goods.

DETAILED DESCRIPTION

There is a tendency toward the aforementioned cartesian coordinate robots and articulated-arm robots becoming larger. For example, cartesian coordinate robots that hold a product from the top need vertically long arms. Such robots cannot be used in a vertically limited space, such as a place with a low ceiling. To avoid known obstacles, it is necessary to provide a redundant number of articulations to articulated-arm robots that hold a product from the top.

In addition, when products are loaded in a cubic space which has an intermediate shelf, an additional number of redundant articulations need to be applied to pick up a product from the intermediate shelf, leading to a problem of increasing the size of robots.

In general, according to one embodiment, a cargo handling apparatus includes a first movement mechanism, a second movement mechanism, a holding unit, a third movement mechanism, a fourth movement mechanism and a conveyor. The first movement mechanism is movable in a first direction. The second movement mechanism is connected to the first movement mechanism and is movable on a first horizontal plane intersecting the first direction. The holding unit is connected to the second movement mechanism and holds an object to be picked up. The third movement mechanism is arranged below the first movement mechanism, the second movement mechanism and the holding unit, and is movable in the first direction. The fourth movement mechanism is connected to the third movement mechanism and is movable on a second horizontal plane opposed to the first horizontal plane. The conveyor is connected to the fourth movement mechanism, and loads and conveys the object held by the holding unit.

In the following, the cargo handling apparatus and method according to the present embodiment will be described in detail with reference to the drawings. In the embodiment described below, elements specified by the same reference numbers carry out the same operations, and a duplicate description of such elements will be omitted.

First Embodiment

The cargo handling apparatus according to the first embodiment will be explained with reference toFIG. 1.

A cargo handling apparatus100according to the first embodiment includes a first vertical member101, a second vertical member102, a third vertical member103, a fourth vertical member104, a fifth vertical member105, a sixth vertical member106, a first horizontal member107, a second horizontal member108, a third horizontal member109, a fourth horizontal member110, a first vertical movement mechanism111, a horizontal movement mechanism112, a first depth-direction movement mechanism113, a holding unit moving mechanism114, a holding unit115, a second vertical movement mechanism116, a second depth-direction movement mechanism117, and a conveyor118.

The first vertical movement mechanism111is also referred to as a first movement mechanism, and a combination of the horizontal movement mechanism112and the first depth-direction movement mechanism113is referred to as a second movement mechanism. The second vertical movement mechanism116is also referred to as a third movement mechanism, and the second depth-direction movement mechanism117is also referred to as a forth movement mechanism.

The first vertical member101, the second vertical member102, the third vertical member103, the fourth vertical member104, the fifth vertical member105, the sixth vertical member106, the first horizontal member107, the second horizontal member108, the third horizontal member109, and the fourth horizontal member110are supporting members which form a framework of the cargo handling apparatus100, and together they are also referred to as a base.

The base according to the present embodiment is formed in the following manner. The first vertical member101, the third vertical member103, and the fifth vertical member105stand in such a manner that one end of each member is grounded, and another end of each member is coupled to the first horizontal member107. The second vertical member102, the fourth vertical member104, and the sixth vertical member106stand in such a manner that one end of each member is grounded, and another end of each member is coupled to the second horizontal member108. The third horizontal member109is horizontally coupled to the first horizontal member107and the second horizontal member108in such a manner that one end is coupled in the vicinity of a position where the third vertical member103is coupled, and another end is coupled in the vicinity of a position where the fourth vertical member104is coupled. The fourth horizontal member110is horizontally coupled to the first horizontal member107and the second horizontal member108in such a manner that one end is coupled in the vicinity of a position where the fifth vertical member105is coupled, and another end is coupled in the vicinity of a position where the sixth vertical member106is coupled.

The base is not limited to the aforementioned shape, but may be formed so as to support the first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, the holding unit115, the second vertical movement mechanism116, the second depth-direction movement mechanism117, and the conveyor118.

The first vertical movement mechanism111is connected to the third vertical member103, fourth vertical member104, fifth vertical member105, and sixth vertical member106of the base so as to be movable in the vertical direction (Y axis direction). For example, guide rails are attached along the third vertical member103, fourth vertical member104, fifth vertical member105, and sixth vertical member106of the base in the vertical direction so that the first vertical movement mechanism111vertically moves along the guide rails.

The horizontal movement mechanism112is connected to the first vertical movement mechanism111so as to be movable in the horizontal direction (X axis direction). For example, a guide rail is attached along the first vertical movement mechanism111in the horizontal direction so that the horizontal movement mechanism112horizontally moves along the guide rail.

The first depth-direction movement mechanism113is connected to the horizontal movement mechanism112so as to be movable in the depth direction (Z axis direction). For example, a guide rail is attached along the horizontal movement mechanism112in the depth direction so that the first depth-direction movement mechanism113moves along the guide rail in the depth direction.

The holding unit moving mechanism114is connected to the first depth-direction movement mechanism113so as to be movable in the depth direction. For example, a guide rail is attached along the bottom of the first depth-direction movement mechanism113in the depth direction so that the holding unit115moves along the depth-direction movement mechanism113in the depth direction. In this embodiment, the holding unit115is movable between both ends of the first depth-direction movement mechanism113, and accordingly, the moving range of the holding unit115is greater than that of the first depth-direction movement mechanism113within the base.

The holding unit115is connected to the first depth-direction movement mechanism113, and holds a product to be picked up (hereinafter referred to as an object). The holding unit115may be set as rotatable so as to deal with various kinds of objects. The holding unit115includes a suction power source such as a compressor, and a controllable open valve that can be opened and closed, such as an electromagnetic valve. The holding unit115uses at least one suction pad to hold an object by suction and to release the object by stopping the suction through the open valve. A plurality of holding units115may be used to obtain a desired carrying force. It is desirable to use a pad formed of an elastic material having a bellows shape, or supported by a spring to adjust the distance between the object and the holding unit115when they are in contact with each other. The holding unit115may be formed in such a manner as to hold an object from both sides, instead of applying a suction pad. The configuration of the holding unit115may vary if the function of moving an object is achieved.

The second vertical movement mechanism116is placed below the first vertical movement mechanism111and is connected to the third vertical member103, fourth vertical member104, fifth vertical member105, and sixth vertical member106of the base so as to be movable in the vertical direction. The second vertical movement mechanism116vertically moves along the guide rails of the base in a similar manner to the first vertical movement mechanism111.

The second depth-direction movement mechanism117is connected to the second vertical movement mechanism116so as to be movable in the depth direction. For example, a guide rail is attached along the second vertical movement mechanism116in the depth direction so that the second depth-direction movement mechanism117moves along the second vertical movement mechanism116in the depth direction.

The conveyor118is a conveyor such as a belt conveyor or a roller conveyor which is connected to the second depth-direction movement mechanism117. The conveyor118carries an object loaded thereon by rotating rollers with a rotation force applied to a motor.

The pick-up process of the cargo handling apparatus100according to the first embodiment will be explained with reference toFIGS. 2 to 7.

It is assumed that boxes loaded in a loading box201are picked up as objects202and203, and the objects202and203are moved to a bench205.FIGS. 2 to 7illustrate a case where the object202is picked up.

The loading box201is a shelf with a lattice/grid type of enclosure and has wheels at the bottom. The loading box201can move with the products being loaded. In this embodiment, the loading box201can be secured within the base. The loading box201is secured by the base when a pick-up operation is performed. The loading box201is not limited to being secured within the base, but may be secured adjacent to the cargo handling apparatus100.

The bench205is a destination of an object carried from the loading box201, and may be a static bench to temporarily keep the object, or may be a movable bench to carry the object to another location by means of a belt conveyor. In this embodiment, it is assumed that a movable bench is used, and an object carried to the bench205from the loading box201is sequentially carried to another location.

In addition, it is assumed that the position of objects to be loaded within the loading box201and the order of picking up the objects are predetermined, and a controller (not shown in the drawings) controls the holding unit115to hold the object and controls each movement mechanism of the cargo handling apparatus100to move by a predetermined distance to the position where the objects can be loaded to the conveyor118. Methods to control the movement mechanism include an open-loop control method which allows each movement mechanism to move by rotating a step motor a predetermined amount based on a designated pulse, or a close-loop control method which allows each movement mechanism to move to a designated location by minimizing an error between a target value and a value measured by a location sensor.

FIG. 2illustrates an initial state before proceeding with the cargo handling processing. The loading box201is placed in the cargo handling apparatus100. The cargo handling apparatus100is arranged close to the bench205, which is a destination of an object from the conveyor118, so that the object is carried from the conveyor118to the bench205.

FIG. 3illustrates a state where the cargo handling apparatus100holds the object202. The first vertical movement mechanism111moves down (the negative direction of the Y axis) to the position which allows the holding unit115to hold the object202. It is assumed that the second vertical movement mechanism116is initially placed at a height where the object202can be loaded on the conveyor118. If the conveyor118is placed at a position where the object202cannot be loaded, the second vertical movement mechanism116vertically moves to the position flush with the bottom of the object202so that the object202can be loaded on the conveyor118.

The first vertical movement mechanism113moves in the depth direction (the negative direction of the Z axis) to the position allowing the holding unit115to hold the object202by applying suction to the object202. The holding unit115holds the object202by suction at the front surface and the top surface. The horizontal movement mechanism112may move in the horizontal direction (the X axis direction) in accordance with the position of the object202. Similar to the first depth-direction movement mechanism113, the second depth-direction movement mechanism117moves in the depth direction (the negative direction of the Z axis) to the front surface of the object202. The edge of the conveyor118may be placed near the bottom of the front surface of the object202. It is acceptable that the edge is placed slightly higher than the bottom, but it is desirable that the edge is placed below the bottom of the object202. Accordingly, the object202is securely loaded on the conveyor118.

FIG. 4illustrates a state where the object202is loaded on the conveyor118. The second depth-direction movement mechanism117moves in the positive direction of the Z axis while the holding unit115holds the object202. The conveyor118, which is a belt conveyor, moves in the Z axis direction so that a carrier force is applied to the top and bottom surfaces of the object202by sandwiching the object202between the holding unit115and the conveyor118. This allows the object202to be easily loaded onto the conveyor118. t is desirable that the moving speed of the second depth-direction movement mechanism117is equal to the moving speed of the conveyor118to prevent the object202from falling.

When the object202reaches a predetermined position of the conveyor118, the movement of the second depth-direction movement mechanism117and the conveyor118is stopped. By the above process, loading of the object202to the conveyor118is completed. If the object202is lightweight, the motor is not energized so as to allow the conveyor118to be idled. In this state, the object202moves on the conveyor118while being held by the holding unit115to the predetermined position.

FIG. 5illustrates a state where the holding unit115is retracted so as to not obstruct the movement of the object202.

The holding unit115releases the object202by stopping suction, and the first vertical movement mechanism111moves upward to separate from the object202. The amount of movement of the first vertical movement mechanism111may be determined so that the first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, and the holding unit115do not collide with each other when the conveyor carries the object.

FIG. 6illustrates a state where the conveyor118is placed alongside the bench205.

The second depth-direction movement mechanism117moves toward the bench205, the second vertical movement mechanism116vertically moves to a position where the edge of the conveyor118facing the bench205is adjacent to the bench205, and the object202is carried without incurring shock to the bench205. Specifically, the second vertical movement mechanism116moves to the position where the edge of the conveyor118is slightly higher than the edge of the bench205. When the second depth-direction movement mechanism117is moving, the conveyor118may be stopped so that the object202is stationary, or may be moving at a speed so that the object202does not fall.

FIG. 7illustrates a state where the object202is being carried onto the bench205from the conveyor118. The conveyor118moves so that the object is carried onto the bench205by rotating the conveyor. The speed of conveyor118is controlled, taking the moving speed of bench205into consideration so that the object202does not fall when entering the bench205. The cargo handling processing of the cargo handling apparatus100is completed by the above operation.

Another example of the pick-up process of the cargo handling apparatus100according to the first embodiment will be explained with reference toFIGS. 8 to 11.

It is assumed that the loading box201loads a great number of objects. When a great number of objects are loaded, a load is applied to objects placed at lower positions. Due to the applied load, objects may be deformed or damaged. To avoid this, there may be a case where an intermediate shelf is provided to the loading box to disperse objects, and objects are loaded on the intermediate shelf.FIGS. 8 to 11show the case where an intermediate shelf801is provided to the loading box201, and an object802is picked up from the intermediate shelf.FIG. 8illustrates an initial state when an object is to be picked up from the intermediate shelf801. The first vertical movement mechanism111moves up (the positive direction of the Y axis) to the position allowing the holding unit115to hold the object802placed on the intermediate shelf801. When the first vertical movement mechanism111moves up, the first depth-direction movement mechanism113and the holding unit115moves to the outside of the loading box201so as to not strike the intermediate shelf. Specifically, the first depth-direction movement mechanism113and the holding unit115move in the positive direction of the Z axis. Then, the first vertical movement mechanism111moves up.

Similarly, the second depth-direction movement mechanism117and the conveyor118move in the positive direction of the Z axis so as to not strike the intermediate shelf801, and then the second vertical movement mechanism116moves to the position close to the upper surface of the intermediate shelf801. Specifically, the second vertical movement mechanism116moves to the position where the edge of the intermediate shelf801is flush with the edge of the conveyor118, or the edge of the conveyor118is lower than the edge of the intermediate shelf801.

FIG. 9illustrates a state where the object802is picked up from the intermediate shelf801. The first depth-direction movement mechanism113moves toward the object802placed on the intermediate shelf801. Then, the holding unit115suctions and holds the object802.

FIG. 10illustrates a state where the object802is loaded onto the conveyor118. The holding unit115moves in the positive direction of the Z axis while holding the object802. The operation of the holding unit115and the conveyor118is similar to that explained with reference toFIG. 4.

FIG. 11illustrates a state where the conveyor118is placed alongside the bench205. The second vertical movement mechanism116moves down so that the edge of the bench205is flush with the edge of the conveyor118. Since the holding unit115does not interfere when the object802is moved to the bench205, the holding unit115does not have to be retracted. The operation of carrying the object802from the conveyor118to the bench205is similar to that shown inFIG. 7, and the explanation thereof will be omitted. The operation of picking up the object802loaded on the intermediate shelf801is completed by the above.

According to the first embodiment, an object is picked up from the loading box by the holding unit and by the conveyor that move in the vertical or depth direction within the base. This implements a cargo handling apparatus having substantially the same size as the range of motion of the holding unit and the conveyor, and accomplishes downsizing of the apparatus. In addition, the holding unit and the conveyor, by being able to move independently in the vertical or depth direction, enables the application of the apparatus to the existing carrying belt conveyor and the existing loading box having an intermediate shelf. Furthermore, the holding unit and the conveyor operate cooperatively.

Specifically, when picking up the object, the conveyor moves close to the holding unit to shorten the time that the holding unit itself supports the object, and the conveyor moves to the height of the bench which is the destination of the object to smoothly move the object to the bench. Accordingly, the apparatus according to the first embodiment picks up or carries an object stably even for dealing with heavy objects or objects at a higher location.

Second Embodiment

In the first embodiment, the location of objects to be loaded within a loading box or the like, the number of objects, and the order of picking up the objects are predetermined, and the objects can be picked up by controlling a predetermined driving power and the order. The second embodiment is different from the first embodiment in that an image sensor detects the position of objects to be loaded. The function of detecting the position of objects achieves the application of the cargo handling apparatus for any arrangement of objects, and increases versatility.

The cargo handling apparatus according to the second embodiment will be explained with reference to the block diagram ofFIG. 12.

A cargo handling apparatus1200according to the second embodiment includes the first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, the holding unit115, the second vertical movement mechanism116, the second depth-direction movement mechanism117, the conveyor118, an image sensor1201, a shape detector1202, and a controller1203.

The image sensor1201is a stereo camera sensor or a distant image sensor such as a laser range finder which can obtain three-dimensional positional information, and the image sensor1201captures an image or a movie of an object and generates image data.

The shape detector1202receives the image data from the image sensor1201, and detects an upper position and a lower position of the object based on the image data. The shape detector1202generates positional information including the upper position and the lower position of the object, the distance to the upper position from a predetermined point, and the distance to the lower position from the predetermined point in the depth direction.

The controller1203receives the positional information from the shape detector1202, drives the first vertical movement mechanism111, the horizontal movement mechanism112, and the first depth-direction movement mechanism113so that the holding unit115moves toward the upper position, and drives the second vertical movement mechanism116and the second depth-direction movement mechanism117so that the conveyor118moves toward the lower position, based on the positional information.

To control the driving operation, the controller1203generates a driving signal indicating the driving amount for each of the first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, the second vertical movement mechanism116, and the second depth-direction movement mechanism117. In addition, the controller1203generates a holding control signal to control the holding operation of the holding unit115, and a convey control signal to control the carrying operation of the conveyor118.

The first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, the second vertical movement mechanism116, and the second depth-direction movement mechanism117each receive a driving signal from the controller1203to be driven with the driving amount indicated by the driving signal.

The holding unit115receives a holding control signal from the controller1203to start or stop the holding operation based on the holding control signal.

The conveyor118receives a convey control signal from the controller1203to start or stop rotation of the conveyor, or to adjust the speed of rotation based on the convey control signal.

The shape of the cargo handling apparatus1200according to the second embodiment is similar to the cargo handling apparatus100according to the first embodiment, and the explanation thereof will be omitted. The image sensor1201may be fixed at a position where an image of an object in the loading box can be captured. The shape detector1202and the controller1203may be arranged as a control board on the base, or arranged remotely from the cargo handling apparatus1200. When remotely arranged, image data is received via a wire or wirelessly from the cargo handling apparatus1200, and a holding control signal and a convey control signal are sent back to the cargo handling apparatus1200.

An example of positional information generation in the shape detector1202will be explained with reference toFIG. 13.

FIG. 13illustrates image data acquired from the image sensor. The image is captured from the opened side of the loading box201in which two boxes are loaded. A relationship of each of coordinate axes is the same as those shown inFIG. 2. InFIG. 13, the bottom of the loading box201is set as the base line.

The shape detector1202performs image recognition of the image data, and extracts three-dimensional positional information or RGB image information to recognize the shape of an object. In the example shown inFIG. 13, two rectangles1301and1302are recognized, and a rectangle having the maximum value in the vertical direction (Y axis direction) and the minimum value in the depth direction (Z axis direction) is set as an object.

That is, a box placed closest to the holding unit and at the top is picked up first. In this example, the rectangle1301is set as an object. The shape detector1202obtains an upper position1303of the object, and computes coordinates of the upper position1303and the distance from the predetermined point to the upper position1303. The shape detector1202also obtains a lower position1304of the object, and computes coordinates of the lower position1304and the distance from the predetermined point to the lower position1304.

The shape detector1202accordingly obtains data regarding the coordinates of the upper position1303, the distance of the upper position1303, the coordinates of the lower position1304, and the distance of the lower position1304as positional information. The coordinates of the upper position1303include coordinates (at least a Y axis component) at the highest position of the object in the vertical direction (Y axis direction). The coordinates of the lower position1304include coordinates (at least a Y axis component) at the lowest position of the object in the vertical direction (Y axis direction). For a rectangular object, the coordinates of the top surface of rectangle1301may be the coordinates of the upper position1303, and the bottom surface of rectangle1301may be the coordinates of the lower position1304.

The pick-up process of the cargo handling apparatus1200according to the second embodiment will be explained with reference to the flowcharts ofFIGS. 14A to 14B.

In step S1401, the image sensor1201captures an image inside of the loading box and obtains image data.

In step S1402, the shape detector1202performs image recognition of the image data to detect the shape and determine an object.

In step S1403, the shape detector1202computes the upper position and the lower position of the object for which the shape is recognized. The second embodiment assumes the case where a box is an object to be picked up. The upper position and the lower position are computed for the object placed at the highest position in the vertical direction and at the foremost position in the depth direction.

In step S1404, the controller1203determines whether the object is placed at a position higher than the intermediate shelf. This determination may be made by comparing the upper position and the lower position computed in the step S1403with a predetermined position of the intermediate shelf. The determination may also be made by analyzing the position of the intermediate shelf from the image data if possible.

In such a case, the shape detector1202or the controller1203may determine whether or not the object is placed higher than the intermediate shelf based on the image data. If the object is placed higher than the intermediate shelf, step S1413is executed, and if the object is placed lower than the intermediate shelf, step S1405is executed.

In step S1405, the first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113, and the holding unit moving mechanism114move the holding unit115to the upper position of the object in response to the driving signal received from the controller1203indicating the driving amount for moving to the upper position.

In step S1406, the second vertical movement mechanism116, and the second depth-direction movement mechanism117move the conveyor118to the lower position of the object in response to the driving signal received from the controller1203indicating the driving amount for moving to the lower position.

In step S1407, the holding unit115holds the object in response to the holding control signal received from the controller1203indicating the initiation of suction.

In step S1408, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, the holding unit115, and the conveyor118cooperatively work in response to the driving signals, holding control signals, and convey control signals so that the object is moved to a predetermined position of the conveyor118and loaded on the conveyor118.

In step S1409, after the object is loaded at the predetermined position of the conveyor118, the holding unit115releases the object in response to the holding control signal received from the controller1203indicating the stoppage of suction.

In step S1410, the first vertical movement mechanism111retracts in response to a driving signal from the controller1203so as to not interfere with movement of the object.

In step S1411, the second vertical movement mechanism116and the second depth-direction movement mechanism117move the conveyor118to a position where the object can be carried to the bench in response to a driving signal received from the controller1203.

In step S1412, the conveyor118conveys the object to the bench in response to a convey control signal received from the controller1203. The object is carried to the bench by rotating the conveyor. This maintains stability of the object.

In step S1413, the first depth-direction movement mechanism113retracts in response to a driving signal from the controller1203.

In step S1414, the second depth-direction movement mechanism117retracts in response to a driving signal from the controller1203.

In step S1415, the first vertical movement mechanism111moves to the uppermost position of the base in response to a driving signal from the controller1203.

In step S1416, the second vertical movement mechanism116moves the conveyor118to the lower position of the object placed on the intermediate shelf, or to the edge of the intermediate shelf if only one object is placed on the intermediate shelf, in response to a driving signal from the controller1203.

In step S1417, the first vertical movement mechanism111, the horizontal movement mechanism112, the first depth-direction movement mechanism113and the holding unit moving mechanism114move the holding unit115to the upper position of the object in response to the driving signal received from the controller1203indicating the driving amount for moving to the upper position.

In step S1418, the holding unit115holds the object in response to the holding control signal received from the controller1203indicating the initiating of suction.

In step S1419, the horizontal movement mechanism112, the first depth-direction movement mechanism113, the holding unit moving mechanism114, the holding unit115, and the conveyor118cooperatively work in response to the driving signals, holding control signals, and convey control signals so that the object is moved to a predetermined position of the conveyor118and loaded on the conveyor118.

In step S1420, after the object is loaded at the predetermined position of the conveyor118, the holding unit115releases the object in response to the holding control signal received from the controller1203indicating the stoppage of suction.

In step S1421, the second vertical movement mechanism116and the second depth-direction movement mechanism117move the conveyor118to a position where the object can be carried to the bench in response to a driving signal received from the controller1203.

In step S1422, the conveyor118carries the object to the bench in response to a convey control signal received from the controller1203. The cargo handling processing of the cargo handling apparatus1200is completed by the above operation.

If the loading box becomes empty during the cargo handling processing according to the present embodiment, another loading box in which objects are loaded is replaced with the empty box, and the same processing may be repeated. The empty loading box may be replaced with the next loading box manually or by using a means for pushing the empty box out of the base and taking the next loading box into the base.

For example, for the case where the image sensor is not used, after a predetermined number of cargo handling processes are completed, the loading box is assumed to be empty, and a box driving unit (not shown in the drawings) pushes the loading box out and takes the next loading box in. For the case where the image sensor is used, the controller determines whether an object remains in the loading box based on the image data, and if the controller determines that there is no object, the box driving unit pushes the loading box out and takes the next loading box in.

According to the second embodiment, objects are detected based on the image data obtained by the image sensor, and the cargo handling processing is not limited to predetermined objects or predetermined arrangements, but can be applied to any arrangements of objects, thus improving versatility of the cargo handling apparatus.

The aforementioned embodiments assume the case where the base stands upright in the vertical direction (Y axis direction), and the first vertical movement mechanism111and the second vertical movement mechanism116move in the vertical direction. However, the second embodiment may be applied to the case where the base is tilted due to the shape of the base. In such a case, the first vertical movement mechanism111(first movement mechanism) and the second vertical movement mechanism116(third movement mechanism) may move along the direction of the tilt (first direction). The horizontal movement mechanism112and the first depth-direction movement mechanism113(second movement mechanism) may move on the XZ plane crossing the first direction (first approximately horizontal plane). The second depth-direction movement mechanism117(fourth movement mechanism) connected to the third movement mechanism may move on the XZ plane (second approximately horizontal plane) facing the first approximately horizontal plane). The first and second approximately horizontal planes are not limited to be exactly parallel to each other, but may be inclined toward the first direction or the vertical direction.

In the aforementioned embodiments, the holding unit115and the conveyor118are moved upon the movement of each movement mechanism, but the holding unit115and the conveyor118may be movable independently from the movement mechanisms. For example, the cargo handling apparatus may include the holding unit115, which is attached to the end of an arm movable in the same range as the first and second movement mechanisms and in three axial directions, and the conveyor118movable in the same range as the third and fourth movement mechanisms. Such a cargo handling apparatus realizes downsizing of the apparatus while establishing the same stability in carrying objects as the apparatus according to the first and second embodiments.