JP7179680B2 - Unloading device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an unloading device, and more particularly, to an unloading device for individually unloading a plurality of works stacked in multiple stages in a truck cargo room, a container room, or the like.

2. Description of the Related Art Conventionally, various types of unloading devices are already known as unloading devices for individually unloading a plurality of works stacked in multiple layers in a truck loading room, a container room, or the like. Here, in Patent Document 1 below, as shown in FIGS. Disclosed is an unloading device 201 having a robot hand 204 capable of sucking the top surface w3). As a result, the workpiece w can be held without requiring a gap for a part of the robot hand 204 (for example, claws that sandwich both sides of the workpiece w) to enter both sides of the workpiece w. Therefore, even if a plurality of works w are multi-stacked in contact with the side wall of the truck cargo room t, the multi-stacked works w can be unloaded individually.

Japanese Patent No. 6172293

However, in the technique of Patent Document 1 described above, for example, when the robot hand 204 sucks only the front surface w2 of the work w, the work w deforms due to its own weight (the work w loses its shape) during unloading. was there. In particular, when the work w is made of cardboard or the like, this problem is conspicuous.

An object of the present invention is to solve such problems, and an object of the present invention is to provide an unloading device for unloading a plurality of works stacked in multiple layers in a truck loading room, a container room, or the like. It is to prevent deformation of the work due to

According to one feature of the present disclosure, an unloading device for individually unloading a plurality of multi-stacked works includes a robot, a robot hand attached to the robot, a controller for controlling the robot, and the robot hand. device. The robot hand includes a hand base and a holding unit attached to the hand base so as to hold the uppermost workpiece. A receiving plate unit is assembled to the hand base. The receiving plate unit includes a slide base attached to the hand base and a receiving table attached to the slide base so as to be able to move forward and backward. When the robot pulls out the uppermost work held by the holding unit, the receiving table can receive and support the bottom surface of the pulled out uppermost work. When the control device determines that there is a lower workpiece under the uppermost workpiece, even if the robot pulls out the uppermost workpiece held by the holding unit, the leading edge of the receiving table and the leading edge of the receiving table are separated from each other before and after the extraction. The receiving table advances with respect to the slide base at a speed synchronous with the pull-out speed so that the tip distance from the front surface of the work facing the work is held at the first distance.

Therefore, the table can receive and support the bottom surface of the uppermost work throughout the entire process of drawing out the uppermost work (from the start of drawing to the completion of drawing). Therefore, the receiving table can firmly support the bottom surface of the uppermost workpiece. That is, it is possible to prevent deformation of the workpiece due to its own weight during unloading.

According to another feature of the present disclosure, the backing plate unit is attached to the hand base so as to be able to move up and down. A tension spring is hooked between the receiving plate unit and the hand base.

Therefore, when unloading the uppermost work that has no lower work under it, the receiving table that supports the uppermost work can be pressed against the floor surface without requiring a lifting actuator. Therefore, the receiving table can receive and support the uppermost work without tilting the robot hand significantly forward.

According to another feature of the present disclosure, in the initial state before the holding unit holds the uppermost workpiece, the receiving table is at a position where the tip of the receiving table and the tip of the holding unit are retreated by a second distance. is set.

Therefore, when unloading the uppermost work under which the lower work is located, the uppermost work can be unloaded even if there is a positional deviation between the uppermost work and the lower work in the front-rear direction.

According to another feature of the present disclosure, the lifting and lowering of the receiving plate unit with respect to the hand base is performed by a substantially U-shaped guide frame provided on the receiving plate unit. The guide frame is formed by press molding.

Therefore, compared with the case where the guide frame is formed by shaving metal, the guide frame can be easily formed.

Also, according to another feature of the present disclosure, the holding unit is attached to the hand base so as to be able to move up and down. A roller is rotatably attached to the tip of the receiving table.

Therefore, when unloading the uppermost work with the lower work below, even if the holding unit holds the upper part of the uppermost work, the holding unit rises with respect to the hand base. Therefore, the uppermost work can be pulled out without causing breakage of the uppermost work and peeling of the uppermost work.

Also, according to another feature of the present disclosure, the receiving table is attached to the slide base via the intermediate frame so as to be able to move back and forth. The intermediate frame is attached to the slide base and the receiving table so as to be able to move forward and backward.

Therefore, even if a large advance amount (advance amount) of the receiving table is secured, there is no need to secure a retraction space (retreat space) for the receiving plate table behind the slide base. Therefore, the space behind the slide base can be saved.

1 is an overall side view of an unloading device according to an embodiment of the present invention; FIG. This figure shows the unloading operation in the cargo room of the truck. 2 is an enlarged view of the robot hand of FIG. 1; FIG. FIG. 3 is a plan view of the robot hand of FIG. 2; FIG. 3 is a cross-sectional view taken along line IV-IV of FIG. 2; FIG. 3 is a plan view of the receiving plate unit of FIG. 2; FIG. 5 shows a state in which the receiving table has advanced to the forward end. FIG. 11 is a diagram for explaining the procedure of unloading work, and illustrates the case of unloading the uppermost work under which there is the lower work. FIG. 8 is a diagram for explaining a procedure following FIG. 7; FIG. 9 is a diagram for explaining the procedure following FIG. 8; It is a figure explaining the procedure of unloading work, and is explaining the case where the uppermost stage work with no lower stage work below is unloaded. FIG. 11 is a diagram for explaining the procedure following FIG. 10; FIG. 12 is a diagram for explaining the procedure following FIG. 11; FIG. 13 is a diagram for explaining a procedure following FIG. 12; FIG. 8 is a diagram for explaining a case where positional deviation occurs between the uppermost work and the lower work in FIG. 7; It is an overall side view of a conventional unloading device. This figure shows the unloading operation in the cargo room of the truck. 16 is an enlarged view of the robot hand of FIG. 15; FIG.

Embodiments for carrying out the present invention will be described below with reference to FIGS. 1 to 14. FIG. In the following description, up, down, front, back, left, and right refer to the up, down, front, back, left, and right directions shown in the above drawings, that is, the articulated robots 3 are arranged in multiple directions. When the direction in which the workpiece W is viewed is forward, the directions of up, down, front, rear, left, and right are shown.

First, referring to FIG. 1, the overall configuration of the unloading device 1 will be described. This unloading device 1 mainly comprises a truck 2 capable of self-propelled on the floor F of a truck cargo room T, an articulated robot 3 mounted on the truck 2, and a robot hand attached to the articulated robot 3. 4 and a control device 5 mounted on the truck 2 .

The carriage 2, the articulated robot 3, the robot hand 4, and the control device 5 will be individually described below. In addition, as is clear from FIG. 1, a plurality of works W made of corrugated cardboard having a rectangular parallelepiped shape and having six sides are stacked in multiple layers in the cargo room T of the truck. In addition, the plurality of multi-tiered works W are multi-tiered so as to be adjacent to each other in the depth direction (front-rear direction) and width direction (left-right direction) of the truck cargo chamber T as well. A plurality of works W stacked in multiple layers so as to be adjacent to each other in the width direction are in contact with a side wall (not shown) of the truck luggage compartment T. As shown in FIG.

Further, as is clear from FIG. 1, the uppermost work W among the plurality of multi-stacked works W is referred to as "uppermost work WH", and the work W below this uppermost work W is referred to as " The lowermost work W is referred to as the lowermost work WLL. In addition, for example, when the plurality of multi-stacked works W are left in two stages after unloading, the work W in the second stage from the bottom is treated as the "top work WH", and the work W in the second stage from the bottom is treated as the "top work WH". The work W on the tier is treated as the "lower tier work WL". Similarly, when unloading leaves only one work W from the multi-stacked works W, the work W on the first tier from the bottom is treated as the "top work WH".

First, the truck 2 will be explained. The truck 2 has a traveling device (not shown) mainly composed of a pair of left and right caterpillars 20 . A driving wheel 21 of the caterpillar 20 rotates using a motor (not shown) as a power source. By appropriately controlling the operation of this motor, the left and right caterpillars 20 operate independently. Further, this travel device is equipped with a distance measuring sensor (not shown).

In this embodiment, a laser irradiation type distance measurement sensor is used. From this distance measuring sensor, the side walls (left and right walls, not shown) of the truck cargo room T, the work W, etc. are irradiated with a laser to read the position of the truck 2 in the truck cargo room T, and based on the read data, The position is corrected by controlling the operation of the motor. The cart 2 can move forward and backward and turn left and right by automatic operation or remote control. The carriage 2 moves according to the remaining amount of the work W in the cargo room T of the truck.

Since the truck 2 uses a pair of left and right caterpillars 20 as a traveling device, it moves smoothly even if the floor surface F of the truck cargo room T is uneven by laying, for example, a gridiron. A transport conveyor (not shown) is connected to the carriage 2 . This transport conveyor is arranged from the truck cargo room T to a truck yard (unloading area, not shown). The work W is unloaded from the truck loading chamber T to the truck yard by this transport conveyor. The truck 2 is configured in this way.

Next, the articulated robot 3 will be described. The articulated robot 3 is a six-axis controlled robot, and includes a base 30 mounted on the cart 2, a first robot arm 31 extending from the base 30, and a second robot arm 32 extending from the first robot arm 31. and a third robot arm 33 assembled to the second robot arm 32 . This articulated robot 3 corresponds to the "robot" described in the claims. A 2D camera 6 and a 3D camera 7 are mounted one by one on the second robot arm 32 so as to overlap vertically.

The 2D camera 6 and the 3D camera 7 stereoscopically capture the position and orientation of the carriage 2 in the truck loading chamber T, and the positions and shapes of a plurality of works W (top work WH, bottom work WL, bottom work WLL, etc.). It can be photographed effectively. In addition, the first roller 101 of the receiving table 100 of the receiving plate unit 70, which will be described later, and the front surface of the work facing the first roller 101 of the receiving table 100 (for example, the front surface WL2 of the lower work WL, the uppermost It is possible to measure the tip distance D1 from the front surface WH2) of the work WH. The articulated robot 3 is configured as described above.

Next, the robot hand 4 will be described (see FIGS. 2-4). The robot hand 4 is composed of a hand base 50 attached to the front flange surface of the third robot arm 33 of the articulated robot 3, and a holding unit 60 attached to the front side of the hand base 50 so as to be vertically movable. .

A pair of rollers 51 and 52 (a first roller 51 and a second roller 52) are rotatably assembled via pins 51a and 52a so as to form a left and right pair on the rear side of the left and right side surfaces of the hand base 50. It is The pair of rollers 51 and 52 are rotatably assembled on the rear side of the left and right side surfaces of the hand base 50 so as to form a pair vertically. That is, four pairs (eight pairs) of rollers 51 and 52 are rotatably assembled to the rear side of the left and right side surfaces of the hand base 50 . The pair of rollers 51 and 52 can roll along the sliding surface 82 of the guide frame 81 of the receiving plate unit 70 described later, with the respective outer peripheral surfaces 51b and 52b thereof.

Further, on the front side of the left and right side surfaces of the hand base 50, elongated guide holes 53 are formed along the vertical direction so as to form a pair on the left and right. A guide bolt 62a of a holding unit 60, which will be described later, is inserted into the guide hole 53. As shown in FIG. The guide holes 53 are formed on the front sides of the left and right side surfaces of the hand base 50 so as to form a pair vertically. That is, four guide holes 53 are formed on the front side of the left and right side surfaces of the hand base 50 .

The holding unit 60 is composed of a base plate 61 and a pair of left and right suction portions 65 attached to the base plate 61 . A pair of left and right guide brackets 62 are attached to the base plate 61 so as to protrude toward the hand base 50 (toward the rear side). Guide bolts 62a inserted into the guide holes 53 of the hand base 50 are attached to the left and right guide brackets 62 so as to protrude outward. The guide bolts 62a are attached to the left and right guide brackets 62 so as to form a pair vertically. That is, the base plate 61 is assembled with four guide bolts 62a.

By moving the four guide bolts 62 a of the base plate 61 through the four guide holes 53 of the hand base 50 , the holding unit 60 can be raised and lowered with respect to the hand base 50 . This description corresponds to "the holding unit is attached to the hand base so as to be able to move up and down." A first tension spring 63 is hooked between the hand base 50 and the base plate 61 of the holding unit 60 . Therefore, when the holding unit 60 rises with respect to the hand base 50 , the lifting unit 60 is biased downward by the restoring force of the first tension spring 63 .

The pair of left and right suction portions 65 attracts the front surface WH2 of the uppermost workpiece WH (the surface facing the suction surface 65a of the pair of left and right suction portions 65) by the suction force of the suction source (not shown). By doing so, the uppermost work WH is held (grabbed). This adsorption source can be operated (attracted or released from adsorption) at any timing from the control device 5, which will be described later.

Also, a receiving plate unit 70 is assembled to the hand base 50 . The receiving plate unit 70 includes a rectangular slide base 80 , a rectangular intermediate frame 90 assembled to the slide base 80 so as to be slidable in the front-rear direction, and a rectangular receiving table 100 slidably assembled (see FIGS. 5 and 6). Because of this configuration, the receiving plate unit 70 has a two-step slide mechanism.

A pair of left and right guide frames 81 are assembled to the slide base 80 and have a substantially U-shape in plan view. The pair of left and right guide frames 81 are formed by press forming by bending sheet metal. As described above, four pairs of rollers 51 and 52 (eight rollers 51 and 52) roll on the opposing inner surfaces of the pair of left and right guide frames 81 in a substantially U-shape to A sliding surface 82 is formed along which 51b and 52b are aligned.

The outer peripheral surfaces 51b and 52b of the eight rollers 51 and 52 roll along the sliding surfaces 82 of the pair of left and right guide frames 81, so that the eight rollers 51 and 52 roll against the hand base 50. The unit 70 can be raised and lowered. This description corresponds to "the receiving plate unit is attached to the hand base so as to be able to move up and down" described in the claims.

A top stay 83 is attached to the pair of left and right guide frames 81 . A second tension spring 84 is hooked between the hand base 50 and the top stay 83 of the pair of left and right guide frames 81 of the receiving plate unit 70 . Therefore, when the receiving plate unit 70 rises with respect to the hand base 50 , the rising receiving plate unit 70 is biased downward by the restoring force of the second tension spring 84 .

On the left side of the slide base 80, a first pulley 85 and a second pulley 86 are rotatably assembled in a pair in the front-rear direction. A first timing belt 87 is stretched between the pair of front and rear pulleys 85 and 86 . A motor 88 is connected to the second pulley 86 . Accordingly, when the motor 88 is driven, the first timing belt 87 can be rotated via the second pulley 86 .

In addition, a third pulley 91 and a fourth pulley 92 paired in the front-rear direction are rotatably attached to the center of the intermediate frame 90 in the left-right direction. A second timing belt 93 is stretched over the pair of front and rear pulleys 91 and 92 . Note that the first timing belt 87 and the intermediate frame 90 are assembled via a joint member 94 . Also, the second timing belt 93 and the receiving table 100 are assembled through a joint member 103 , and the second timing belt 93 and the slide base 80 are assembled through a joint member 104 .

Accordingly, when the first timing belt 87 is rotated, the intermediate frame 90 slides together with the rotated first timing belt 87 . That is, the intermediate frame 90 advances with respect to the slide base 80 . By sliding the intermediate frame 90 with the joint member 104 on the slide base 80 as a fixed point, the joint member 103 on the receiving table 100 side advances by the same distance. As a result, the receiving table 100 advances with respect to the slide base 80 .

The front end of the receiving table 100 is tapered, and a first roller 101 is rotatably attached to the tapered front end via a pin 101a. A second roller 102 is rotatably mounted on the upper surface of the receiving table 100 at a rear position of the first roller 101 via a pin 102a. As will be described later, in the initial state before the holding unit 60 holds the uppermost work WH, the receiving table 100 is retreated by a second distance, the retreat distance D2 between the first roller 101 and the front end of the holding unit 60. It is set to the position where This second distance is a preset distance, for example, 100 mm. The robot hand 4 is configured as described above.

Finally, the control device 5 will be explained. The control device 5 is programmed with first software for performing image processing on image data captured by the 2D camera 6 . The control device 5 is programmed with second software capable of recognizing the tip distance D1 measured by the 3D camera 7 . The control device 5 can control the movements of the carriage 2, the articulated robot 3, and the robot hand 4 by using the first software and the second software. Further, the control device 5 is programmed with third software so that the holding unit 60 always holds the uppermost work WH when unloading a plurality of multi-stacked works W individually.

Further, the controller 5 is programmed with fourth software capable of determining whether or not there is a lower work WL below the uppermost work WH when the holding unit 60 holds the uppermost work WH. Further, the controller 5 is programmed with fifth software capable of controlling the operation of the motor 88 . With this fifth software, the control device 5 controls the receiving table 100 relative to the slide base 80 so that the tip distance D1 measured by the 3D camera 7 is held at the first distance before and after the uppermost work WH is pulled out, which will be described later. can control the amount of advance. This first distance is a preset distance, for example, 10 mm. The control device 5 is configured in this way.

Next, the work of unloading the uppermost work WH by the unloading device 1 will be described with reference to FIGS. In this description, the case of unloading the uppermost work WH with the lower work WL below it (see FIGS. 7 to 9) and the case of unloading the uppermost work WH without the lower work WL below it (see FIGS. 10 to 13) ) and , and will be described separately. The determination of the presence or absence of the lower workpiece WL is executed by the fourth software programmed in the control device 5, as already described.

First, the case of unloading the uppermost work WH under which the lower work WL is located will be described. First, the control device 5 executes processing (1A processing) for operating the articulated robot 3 so that the holding unit 60 is at a height position where the uppermost work WH can be held (see FIG. 7). The state shown in FIG. 7 is the initial state before the holding unit 60 holds the uppermost work WH.

Next, the control device 5 operates the articulated robot 3 until the suction surface 65a of the holding unit 60 approaches the front surface WH2 of the uppermost work WH while maintaining the height position of the holding unit 60 (second step). 2A process) is executed. Next, the control device 5 executes a process (3A process) of attracting the front surface WH2 of the uppermost workpiece WH by the attracting surface 65a of the holding unit 60 (see FIG. 8).

As a result, the uppermost work WH can be held by the holding unit 60 . At this time, as is clear from FIG. 8, the first roller 101 of the receiving table 100 and the front surface WL2 of the lower workpiece WL face each other. Next, the control device 5 executes a process (4A process) for advancing the receiving table 100 with respect to the slide base 80 so that the tip distance D1 becomes the first distance. Next, the control device 5 executes a process (5A process) in which the articulated robot 3 pulls out the uppermost work WH held by the holding unit 60 .

Simultaneously with this 5A process, the control device 5 executes a process (6A process) for advancing the receiving table 100 with respect to the slide base 80 so that the tip distance D1 becomes the first distance (see FIG. 9). . As a result, the table 100 can receive and support the bottom surface WH1 of the uppermost work WH pulled out by the articulated robot 3 . In the sixth A process, when the receiving table 100 is advanced, the second roller 102 of the advanced receiving table 100 interferes with the bottom surface WH1 of the uppermost workpiece WH.

As a result, the second roller 102 rotates, so that the uppermost work WH can be smoothly pulled out. Further, the withdrawal speed of the articulated robot 3 in the 5A process and the advance speed of the receiving table 100 in the 6A process are synchronized. As a result, the tip distance D1 can be maintained at the first distance before and after the uppermost work WH is pulled out. Therefore, it is possible to prevent the tip distance D1 from increasing before and after the uppermost workpiece WH is pulled out.

Therefore, the table 100 receives and supports the bottom surface WH1 of the uppermost work WH during the whole process of pulling out the uppermost work WH (from the start of pulling out the uppermost work WH to the completion of pulling out the uppermost work WH). can be done. As a result, the receiving table 100 can firmly support the bottom surface WH1 of the uppermost workpiece WH. Finally, the control device 5 executes a process (7th A process) of placing the uppermost work WH pulled out by the articulated robot 3 on the conveyer. After that, the control device 5 repeats the 1Ath process to the 7thA process. In this manner, the uppermost work WH with the lower work WL below can be unloaded.

Next, the case of unloading the uppermost work WH with no lower work WL below it will be described. First, the control device 5 executes a process (1B process) for operating the articulated robot 3 so that the suction surface 65a of the robot hand 4 faces the front surface WH2 of the uppermost workpiece WH (see FIG. 10). . Next, the control device 5 executes processing (second B processing) for operating the articulated robot 3 so that the holding unit 60 is at a height position where the uppermost workpiece WH can be held.

Then, the receiving plate unit 70 is pressed against the floor surface F against the biasing force of the second tension spring 84 , and the receiving plate unit 70 pressed against the floor surface F resists the biasing force of the second tension spring 84 . and rises relative to the hand base 50. Next, the control device 5 operates the articulated robot 3 until the suction surface 65a of the holding unit 60 approaches the front surface WH2 of the uppermost work WH while maintaining the height position of the holding unit 60 (first step). 3B process).

Next, the control device 5 executes a process (fourth B process) of attracting the front surface WH2 of the uppermost workpiece WH by the attracting surface 65a of the holding unit 60 (see FIG. 11). As a result, the uppermost work WH can be held by the holding unit 60 . Next, the control device 5 executes a process (5B process) of operating the articulated robot 3 so that the robot hand 4 is in a forward tilted posture.

As a result, a gap S is secured below the front surface WH2 of the uppermost workpiece WH held. At this time, the restorative force of the second tension spring 84 lowers the receiving plate unit 70 with respect to the hand base 50 . Therefore, the state in which the receiving plate unit 70 is pressed against the floor surface F against the biasing force of the second tension spring 84 is maintained. Next, the control device 5 executes a process (6th B process) for advancing the receiving table 100 with respect to the slide base 80 so that the tip distance D1 becomes the first distance (see FIG. 12).

Next, the control device 5 executes a process (7th B process) in which the articulated robot 3 pulls out the uppermost work WH held by the holding unit 60 . Simultaneously with this seventh B process, the control device 5 executes a process (eighth B process) for maximally advancing the receiving table 100 with respect to the slide base 80 (see FIG. 13). As a result, the table 100 can receive and support the bottom surface WH1 of the uppermost work WH pulled out by the articulated robot 3 .

In the eighth B process, when the receiving table 100 is advanced, the second roller 102 of the advanced receiving table 100 interferes with the bottom surface WH1 of the uppermost workpiece WH. As a result, the second roller 102 rotates, so that the uppermost work WH can be pulled out smoothly. Further, the withdrawal speed of the articulated robot 3 in the 7B process and the advance speed of the receiving table 100 in the 8B process are synchronized.

As a result, the positional relationship between the first roller 101 of the receiving table 100 and the floor surface F can be maintained before and after the uppermost work WH is pulled out. Therefore, the table 100 receives and supports the bottom surface WH1 of the uppermost work WH throughout the entire process of pulling out the uppermost work WH (from the start of pulling out the uppermost work WH to the completion of pulling out the uppermost work WH). can be done. Therefore, the receiving table 100 can firmly support the bottom surface WH1 of the uppermost workpiece WH. Finally, the control device 5 executes a process (9th B process) of placing the uppermost work WH pulled out by the articulated robot 3 on the conveyer. In this way, the uppermost work WH with no lower work WL below it can be unloaded.

In the above description of unloading the uppermost work WH having the lower work WL thereunder, for example, as shown in FIG. There may be That is, there is a case where the projecting distance D3 of the front surface WL2 of the lower work WL with respect to the front surface WH2 of the uppermost work WH is the third distance. Even in this case, as already explained, in the initial state, the receiving table 100 is set at a position where the retraction distance D2 is retracted by the second distance, so that the relationship of the third distance<the second distance is established. If it is within the range, the uppermost work WH can be unloaded even if this positional deviation occurs.

Further, in the above description of unloading the uppermost work WH having the lower work WL thereunder, for example, in FIG. 8, the holding unit 60 may hold the lower portion of the uppermost work WH. In this case, when the 5A process and the 6A process described above are executed, the first roller 101 of the receiving table 100 interferes with the front surface WH2 of the uppermost work WH. Then, as already explained, since the holding unit 60 rises with respect to the hand base 50, the uppermost work WH can be pulled out without causing damage to the uppermost work WH and separation of the uppermost work WH. can be done.

The unloading device 1 according to the embodiment of the present invention is constructed as described above. According to this configuration, the control device 5 executes the process (5A process) in which the articulated robot 3 pulls out the uppermost work WH held by the holding unit 60 . Simultaneously with this 5A process, the control device 5 executes a process (6A process) for advancing the receiving table 100 with respect to the slide base 80 so that the tip distance D1 becomes the first distance (see FIG. 9). . The pull-out speed of the articulated robot 3 in the 5A process and the advancing speed of the receiving table 100 in the 6A process are synchronized. Therefore, the tip distance D1 can be maintained at the first distance before and after the uppermost work WH is pulled out. Therefore, the receiving table 100 can receive and support the bottom surface WH1 of the uppermost work WH throughout the entire process of pulling out the uppermost work WH. As a result, the receiving table 100 can firmly support the bottom surface WH1 of the uppermost workpiece WH. That is, it is possible to prevent deformation of the work W due to its own weight during unloading.

Further, according to this configuration, the receiving plate unit 70 is attached to the hand base 50 so as to be able to move up and down. A second tension spring 84 is hooked between the hand base 50 and the top stay 83 of the pair of left and right guide frames 81 of the receiving plate unit 70 . Therefore, when the receiving plate unit 70 rises with respect to the hand base 50 , the rising receiving plate unit 70 is biased downward by the restoring force of the second tension spring 84 . Therefore, when unloading the uppermost work WH that has no lower work WL below it, the receiving table 100 that supports the uppermost work WH can be pressed against the floor surface F without requiring a lift actuator. As a result, the receiving table 100 can receive and support the uppermost work WH without making the robot hand 4 largely tilt forward.

In addition, according to this configuration, in the initial state before the holding unit 60 holds the uppermost work WH, the receiving table 100 is such that the retreat distance D2 between the first roller 101 and the front end of the holding unit 60 is the second distance. It is set to a position that is retracted by Therefore, when unloading the uppermost work WH with the lower work WL below, the uppermost work WH can be unloaded even if there is a positional deviation between the uppermost work WH and the lower work WL. I can take it down.

Further, according to this configuration, the slide base 80 is assembled with a pair of left and right guide frames 81 having a substantially U-shape in plan view. The pair of left and right guide frames 81 are formed by press forming by bending sheet metal. Therefore, the pair of left and right guide frames 81 can be formed easily compared to the case where the pair of left and right guide frames 81 are formed by shaving metal.

Further, according to this configuration, the holding unit 60 is attached to the hand base 50 so as to be able to move up and down. The front end of the receiving table 100 is tapered, and a first roller 101 is rotatably attached to the tapered front end via a pin 101a. Therefore, when unloading the uppermost work WH under which the lower work WL is located, the holding unit 60 rises with respect to the hand base 50 even when the upper part of the uppermost work WH is held by the holding unit 60 . Therefore, the uppermost work WH can be pulled out without causing breakage of the uppermost work WH and separation of the uppermost work WH.

Further, according to this configuration, the receiving plate unit 70 includes a rectangular slide base 80, a rectangular intermediate frame 90 assembled to the slide base 80 so as to be slidable in the front-rear direction, and an intermediate frame 90 and a rectangular receiving table 100 assembled so as to be slidable along the longitudinal direction. Because of this configuration, the receiving plate unit 70 has a two-step slide mechanism. Therefore, even if a large advance amount (advance amount) of the receiving table 100 is secured, it is not necessary to secure a retraction space (retreat space) for the receiving plate table 100 behind the slide base 80 . Therefore, the space behind the slide base 80 can be saved.

It should be noted that the unloading device 1 according to the embodiment of the present invention is not limited to the above-described embodiment, and may be configured by appropriately changing parts as follows. The receiving table 100 of the receiving plate unit 70 may be a retractable mechanism using a ball screw, a rack and pinion, or various cylinders instead of a belt-driven two-stage retractable mechanism.

Further, the holding unit 60 may hold the uppermost work WH by sandwiching it with a pair of left and right claws. Also, various numerical values are not limited to these, and may be arbitrary numerical values as long as the embodiments of the present invention are established. Of course, the first distance may be 0 mm.

In addition, the 2D camera 6 and the 3D camera 7 may be mounted on a pillar erected on the cart 2, a side surface of the receiving table of the receiving plate unit 70, or the like, instead of being mounted on the second robot arm 32. FIG. Of course, the number of units to be mounted is not limited to one unit, and a plurality of units may be installed. Also, the 2D camera 6 and the 3D camera 7 may be mounted side by side without overlapping vertically.

In the embodiment, the outer peripheral surfaces 51b and 52b of the eight rollers 51 and 52 roll along the sliding surfaces 82 of the pair of left and right guide frames 81 so that the eight rollers 51 and 52 roll. A configuration in which the receiving plate unit 70 can be raised and lowered has been described. However, it is not limited to this, and a configuration in which the receiving plate unit 70 can be moved up and down with respect to the hand base 50 by a known linear guide mechanism, a known sliding guide mechanism, or the like may be employed.

1 Unloading device 3 Articulated robot (robot)
4 Robot hand 5 Control device 50 Hand base 60 Holding unit 70 Receiving plate unit 80 Slide base 100 Receiving table D1 Tip distance W Work WH Top work WH1 Bottom WH2 Hand front WL Lower work WL2 Hand front

Claims (6)

An unloading device for individually unloading a plurality of multi-stacked works,
robot and
a robot hand attached to a robot;
a robot, a robot hand, and a controller for controlling the robot hand,
The robot hand includes a hand base and a holding unit assembled to the hand base so as to hold the uppermost work,
A receiving plate unit is assembled to the hand base,
The receiving plate unit includes a slide base attached to the hand base and a receiving table attached to the slide base so as to move forward and backward,
When the robot pulls out the uppermost work held by the holding unit, the receiving table can receive and support the bottom surface of the pulled out uppermost work.
When the control device determines that there is a lower work under the uppermost work,
Even if the robot pulls out the uppermost work held by the holding unit, the tip distance between the front end of the receiving table and the front surface of the work facing the front end of the receiving table is a predetermined first distance before and after the drawing. An unloading device in which the receiving table advances relative to the slide base at a speed synchronous with this withdrawal speed so as to be held at a distance. An unloading device according to claim 1, comprising:
The receiving plate unit is attached to the hand base so that it can be raised and lowered,
An unloading device in which a tension spring is hooked between the receiving plate unit and the hand base. The unloading device according to any one of claims 1 and 2,
The unloading device, wherein in the initial state before the holding unit holds the uppermost workpiece, the receiving table is set at a position where the tip of the receiving table and the tip of the holding unit are retreated by a predetermined second distance. The unloading device according to any one of claims 2 and 3,
Lifting and lowering of the receiving plate unit with respect to the hand base is performed by a substantially U-shaped guide frame provided on the slide base.
The guide frame is a press-formed unloading device. The unloading device according to any one of claims 1 to 4,
The holding unit is attached to the hand base so that it can move up and down,
An unloading device in which a roller is rotatably attached to the tip of the receiving table. The unloading device according to any one of claims 1 to 5,
The receiving table is attached to the slide base via the intermediate frame so as to be able to move forward and backward,
An unloading device in which the intermediate frame is attached to the slide base and the receiving table so as to be movable forward and backward.

Images