Work supply device and work supply method

Abstract

To facilitate picking by a robot arm.SOLUTION: A workpiece supply device 100 includes: a hopper 2 with its top opening, where multiple workpieces W are stored; mounting tables 3A, 3B having upper faces 35a that form a part of a bottom face 22b of the hopper 2, where workpieces W positioned on the upper faces 35a are picked by a robot arm; and lifting mechanisms 4A, 4B that lift the mounting tables 3A, 3B so that the upper faces 35a move between a position of the bottom face 22b and a predetermined picking position P by the robot arm that is higher than the bottom face 22b.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The technology disclosed herein relates to a workpiece supply device. [Background technology]

[0002] Conventionally, workpiece supply devices have been known in which workpieces to be picked by a robot or the like are stacked in bulk. For example, the workpiece supply device disclosed in Patent Document 1 includes a comb-shaped upper tray that is arranged in a container so as to be openable and closable and on which workpieces can be stacked in bulk, and a lower tray that is arranged below the upper tray in the container and has a comb-shaped configuration alternating with the comb teeth of the upper tray. This workpiece supply device drops the workpieces into the lower tray by opening the upper tray on which the workpieces are stacked in bulk. This changes the state of the workpieces stacked in bulk. Next, the workpiece supply device raises the lower tray to the position of the upper tray, closes the upper tray, and lowers the lower tray, thereby transferring the workpieces from the lower tray to the upper tray. In this way, the state of the workpieces stacked in bulk on the upper tray is changed to a state where they can be picked by a robot arm. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-66598 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the work supply device of Patent Document 1 still has room for improvement in terms of ease of picking by a robot arm.

[0005] The technology disclosed herein has been made in consideration of the above points, and its purpose is to provide a work supply device that can improve the ease of picking by a robot arm. [Means for solving the problem]

[0006] The work supply device disclosed herein includes a container, a mounting table, and an elevating mechanism. The container has an open top and accommodates multiple workpieces. The mounting table has an upper surface that forms part of the bottom surface of the container, and works positioned on the upper surface are picked up by a robot arm. The elevating mechanism elevates the container or the mounting table so that the upper surface moves relatively between the position of the bottom surface and a predetermined picking position for the robot arm that is higher than the bottom surface. [Effects of the Invention]

[0007] According to the work supply device, it is possible to improve the ease of picking by the robot arm. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a picking system including a work supply device. [Figure 2] FIG. 2 is a partial cross-sectional view showing the work supply device as viewed from the front. [Figure 3] FIG. 3 is a partial cross-sectional view showing the work supply device as viewed from the right side. [Figure 4] FIG. 4 is a plan view of the work supply device. [Figure 5] FIG. 5 is a block diagram of the control device and its peripheral devices. [Figure 6] FIG. 6 is a schematic diagram showing the initial state of the mounting table. [Figure 7] FIG. 7 is a schematic diagram showing a state during the lifting and lowering operation of the mounting table. [Figure 8] FIG. 8 is a schematic diagram showing a state in which the mounting table has risen to the picking position. [Figure 9] FIG. 9 is a schematic diagram showing a state in which the movable part of the mounting table is sliding. [Figure 10]FIG. 10 is a schematic diagram showing a state in which the sliding movement of the movable part of the mounting table has stopped. [Figure 11] FIG. 11 is a plan view showing the mounting base in a state where the sliding movement of the movable portion is stopped. [Figure 12] FIG. 12 is a schematic diagram showing a state in which the movable part of the mounting table is sliding back to its original position. [Figure 13] FIG. 13 is a view corresponding to FIG. 9, showing a work supply device according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Exemplary embodiments will now be described in detail with reference to the accompanying drawings.

[0010] 1 is a schematic diagram showing the configuration of a picking system 300 including a work supply device 100. The picking system 300 includes the work supply device 100 and a robot 200. In the picking system 300, the work W randomly stacked in the work supply device 100 is picked up by a robot arm 202 of the robot 200 and transported to a predetermined location.

[0011] The robot 200 includes a base 201, a robot arm 202 connected to the base 201, and a robot control unit 205 (see FIG. 5). In this example, the robot 200 is disposed on the left side of the work supply device 100. The robot arm 202 is of a so-called vertically articulated type, and has a plurality of links connected to each other so as to be rotatable in the vertical direction. The base end of the robot arm 202 is rotatably connected to the base 201. A hand 203 is rotatably connected to the tip of the robot arm 202. In other words, the robot arm 202 picks up the work W from the work supply device 100 by, for example, gripping it with the hand 203.

[0012] In addition, a camera 204 is attached to the robot arm 202. In this example, the camera 204 is provided on the hand 203. The camera 2 takes an image of the workpiece W of the workpiece supply device 100. The camera 2 outputs the captured image (image data) of the workpiece W to the robot control unit 205. The camera 2 is an example of an imaging device. Note that instead of the camera 2, a laser scanner, for example, may be used as the imaging device.

[0013] The robot control unit 205 controls various operations of the robot arm 202 (including various operations of the hand 203). The robot control unit 205 determines the position and posture of the workpiece W in the workpiece supply device 100 based on the photographed image (image data) of the workpiece W output from the camera 204. The robot control unit 205 controls the robot arm 202 in accordance with the determined position and posture of the workpiece W to cause the robot arm 202 to pick it up.

[0014] Fig. 2 is a partial cross-sectional view showing the work supply device 100 as viewed from the front. Fig. 3 is a partial cross-sectional view showing the work supply device 100 as viewed from the right side. Fig. 4 is a plan view of the work supply device 100. The work supply device 100 supplies a work W to be picked up by a robot arm 202.

[0015] The work supply device 100 includes a stand 1, a hopper 2, two mounting tables 3A and 3B, two lifting mechanisms 4A and 4B, and two slide mechanisms 5A and 5B as a force application unit 9. That is, the work supply device 100 of this example is provided with two sets of mounting tables 3A and 3B and lifting mechanisms 4A and 4B, and more specifically, two sets of mounting tables 3A and 3B, lifting mechanisms 4A and 4B, and slide mechanisms 5A and 5B.

[0016] The base 1 supports the hopper 2, lifting mechanisms 4A, 4B, etc. The base 1 has four vertical members 11 extending in the vertical direction and eight horizontal members 12, 13 extending in the horizontal direction. The base 1 is formed into a generally rectangular shape by assembling the vertical members 11 and the horizontal members 12, 13. The horizontal members 12 connect the upper parts of adjacent vertical members 11. The horizontal members 13 connect the lower parts of adjacent vertical members 11. An adjuster 14 is provided at the lower end of each of the four vertical members 11. The adjuster 14 adjusts the height of the base 1.

[0017] The hopper 2 has an open top and is configured to accommodate a plurality of workpieces W. The hopper 2 is an example of a container. The hopper 2 has a hopper body 21 and a bottom plate 22.

[0018] The hopper body 21 is formed in a cylindrical shape with an axis extending in the vertical direction. More specifically, the internal space of the hopper body 21 narrows from the top to the bottom. That is, in the hopper body 21, the lower opening 21b is smaller than the upper opening 21a. The bottom plate 22 extends horizontally and is attached to the lower end of the hopper body 21 by, for example, bolting. That is, the bottom plate 22 is provided so as to close the lower opening 21b of the hopper body 21.

[0019] The upper surface of the bottom plate 22 thus provided serves as the bottom surface 22b of the hopper 2. The bottom plate 22 is provided with an opening 22a penetrating in the vertical direction. Two mounting tables 3A and 3B, which will be described later, are arranged in this opening 22a. The hopper 2 is arranged above the base 1. Specifically, a mounting plate 23 extending horizontally is provided at the upper end of the base 1. The hopper 2 is arranged above the base 1 by fastening the bottom plate 22 to the upper surface of the mounting plate 23, for example, by bolts. The mounting plate 23 is provided with an opening 23a that is approximately coaxial with the opening 22a of the bottom plate 22. In this example, the opening 23a of the mounting plate 23 is larger than the opening 22a of the bottom plate 22. The hopper 2 thus formed accommodates a plurality of workpieces W in a bulk state.

[0020] The two mounting tables 3A, 3B have the same configuration. Each of the two mounting tables 3A, 3B has an upper surface 35a that forms part of the bottom surface of the hopper 2, and the workpiece W located on the upper surface 35a is picked up by the robot arm 202. When the two mounting tables 3A, 3B are to be distinguished from each other, they are referred to as the first mounting table 3A and the second mounting table 3B.

[0021] Specifically, each of the two mounting tables 3A and 3B has a table main body 31, a base plate 32, and a movable part 33. In the mounting tables 3A and 3B, the base plate 32, the table main body 31, and the movable part 33 are stacked in this order from the bottom up.

[0022] The table main body 31 is formed in a rectangular shape. More specifically, the table main body 31 is formed in a rectangular shape extending in the vertical direction. The cross-sectional shape of the table main body 31 perpendicular to the vertical direction is rectangular, and more specifically, it is a rectangle with long sides in the front-to-rear direction and short sides in the left-to-right direction. Hereinafter, unless otherwise specified, the "cross-sectional shape" refers to the shape of a cross section perpendicular to the vertical direction. A base plate 32 extending in the front-to-rear direction is attached to the underside of the table main body 31. The length of the base plate 32 in the front-to-rear direction and the length in the left-to-right direction are longer than those of the table main body 31.

[0023] The movable part 33 has the upper surface 35a, and is provided above the table main body 31 so as to be slidable in a direction along the upper surface 35a. Specifically, the movable part 33 is slidable relative to the table main body 31. In this example, the movable part 33 is configured to be slidable in the left-right direction.

[0024] More specifically, the movable section 33 is formed by a mounting plate 34 and a jig 35. In the movable section 33, the mounting plate 34 and the jig 35 are stacked in this order from bottom to top. The mounting plate 34 extends in the front-rear direction and has the same cross-sectional shape as the base body 31. The jig 35 is formed in a plate shape extending in the front-rear direction. The jig 35 has the same length in the left-right direction as the mounting plate 34, but is slightly shorter in the front-rear direction than the mounting plate 34. The jig 35 is located at the top of the mounting bases 3A and 3B. Therefore, the upper surface of the jig 35 becomes the upper surface 35a of the mounting bases 3A and 3B described above. Hereinafter, the upper surface 35a of the jig 35 is synonymous with the upper surface 35a of the mounting bases 3A and 3B.

[0025] The two mounting tables 3A and 3B thus formed are placed adjacent to each other within the opening 22a of the bottom plate 22. The two mounting tables 3A and 3B are adjacent to each other in the left-right direction. The opening 22a of the bottom plate 22 is slightly larger than the cross-sectional size of the two adjacent mounting tables 3A and 3B. Each of the two mounting tables 3A and 3B is arranged so that it can be raised and lowered (i.e., moved up and down). When the upper surface 35a of each of the two mounting tables 3A and 3B is located at the bottom surface 22b of the bottom plate 22 (i.e., the state of the second mounting table 3B shown in Figures 2 and 3), the upper surfaces 35a of the mounting tables 3A and 3B form part of the bottom surface 22b of the hopper 2. That is, in the hopper 2, the opening 22a of the bottom plate 22 is substantially blocked by the upper surfaces 35a of the two mounting tables 3A and 3B. In this example, the upper surfaces 35a of the mounting tables 3A and 3B are horizontal. Note that the phrase "the upper surfaces 35a of the mounting tables 3A and 3B form part of the bottom surface 22b of the hopper 2" naturally includes not only a configuration in which the upper surface 35a and the bottom surface 22b coincide in the vertical direction (i.e., are flush), but also a configuration in which the upper surface 35a is located slightly above or below the bottom surface 22b.

[0026] Each of the two lifting mechanisms 4A, 4B raises and lowers the hopper 2 or the mounting tables 3A, 3B so that the upper surfaces 35a of the mounting tables 3A, 3B move relatively between the position of the bottom surfaces 22b and a predetermined picking position P (see FIG. 8) by the robot arm 202, which is higher than the bottom surfaces 22b. In this example, the lifting mechanisms 4A, 4B raise and lower the mounting tables 3A, 3B. The picking position P is a position for the robot arm 202 to pick up the workpiece W.

[0027] When the two lifting mechanisms 4A and 4B are to be distinguished from each other, they are referred to as the first lifting mechanism 4A and the second lifting mechanism 4B. The first lifting mechanism 4A lifts and lowers the first table 3A, and the second lifting mechanism 4B lifts and lowers the second table 3B.

[0028] The two lifting mechanisms 4A and 4B have the same configuration. Specifically, each of the two lifting mechanisms 4A and 4B has a first air cylinder 41.

[0029] The first air cylinder 41 is disposed inside the gantry 1, below the mounting tables 3A and 3B. In this example, the first air cylinder 41 has two piston rods 41a. The first air cylinder 41 is disposed so that the two piston rods 41a move back and forth in the up and down direction. The first air cylinder 41 is disposed with the two piston rods 41a aligned in the front-to-rear direction. The first air cylinders 41 of the two lifting mechanisms 4A and 4B are attached to a common mounting plate 42 that is provided on the horizontal member 13 via a support member 43.

[0030] The two piston rods 41a of the first air cylinder 41 are connected to the lower surfaces of the base plates 32 of the mounting tables 3A and 3B via connecting members 41b. The mounting tables 3A and 3B rise and fall in response to the advance and retreat of the piston rods 41a. That is, in response to the advance and retreat of the piston rods 41a, the upper surfaces 35a of the mounting tables 3A and 3B move between the position of the bottom surfaces 22b and a picking position P higher than the bottom surfaces 22b. For example, when the piston rods 41a advance, i.e., when the piston rods 41a rise, the mounting tables 3A and 3B rise. On the other hand, when the piston rods 41a retreat, i.e., when the piston rods 41a descend, the mounting tables 3A and 3B descend.

[0031] Each of the two slide mechanisms 5A, 5B is an example of the force application unit 9. The force application unit 9 applies a predetermined force to the workpiece W on the upper surface 35a of the mounting tables 3A, 3B that have moved to the picking position P, thereby displacing the workpiece W on the upper surface 35a in a direction along the upper surface 35a.

[0032] Specifically, each of the two slide mechanisms 5A and 5B slides the movable part 33 when the upper surface 35a of the mounting tables 3A and 3B moves to the picking position P. In this example, the slide mechanisms 5A and 5B slide the movable part 33 in the left-right direction. The two slide mechanisms 5A and 5B have the same configuration.

[0033] When the two slide mechanisms 5A and 5B are to be distinguished from each other, they are referred to as the first slide mechanism 5A and the second slide mechanism 5B. The first slide mechanism 5A slides the movable part 33 of the first mounting table 3A, and the second slide mechanism 5B slides the movable part 33 of the second mounting table 3B.

[0034] The two slide mechanisms 5A, 5B are attached to the corresponding mounting tables 3A, 3B, respectively. That is, the slide mechanisms 5A, 5B move up and down together with the mounting tables 3A, 3B. Specifically, the slide mechanisms 5A, 5B are provided on the rear side of the mounting tables 3A, 3B. Each of the two slide mechanisms 5A, 5B has a second air cylinder 51 and an arm 52.

[0035] The second air cylinder 51 is attached to the base plate 32 of the mounting tables 3A, 3B via a mounting plate 53. The mounting plate 53 extends in the vertical direction and is provided at an end of the base plate 32 that is rearward of the table main body 31. The mounting plate 53 extends to a position higher than the jig 35. The second air cylinder 51 is attached to the upper part of the mounting plate 53. A rib 54 is provided on the rear surface of the mounting plate 53.

[0036] The second air cylinder 51 in this example has two piston rods 51a. The second air cylinder 51 is arranged so that the two piston rods 51a can move back and forth in the left and right directions. The second air cylinder 51 is arranged with the two piston rods 51a lined up one above the other.

[0037] The second air cylinder 51 in this example has a guide block 51b that slides left and right in response to the forward and backward movement of two piston rods 51a. In the second air cylinder 51, the guide block 51b is connected to the movable part 33 of the mounting tables 3A, 3B via an arm 52. The arm 52 is a plate member that extends vertically and is fixed to an end of the mounting plate 34 of the movable part 33 that is rearward of the jig 35. The arm 52 extends to approximately the same height as the mounting plate 53. The guide block 51b is connected to an upper part 12 of the arm 52.

[0038] In this way, the two piston rods 51a of the second air cylinder 51 are connected to the movable parts 33 of the mounting tables 3A and 3B via the guide blocks 51b and the arms 52. The movable parts 33 slide left and right in response to the forward and backward movement of the piston rods 51a. In this example, the second air cylinders 51 of the first slide mechanism 5A and the second air cylinders 51 of the second slide mechanism 5B are arranged with their piston rods 51a facing each other (see FIG. 4). Therefore, the sliding direction of the movable parts 33 in response to the forward and backward movement of the piston rods 51a differs between the first slide mechanism 5A and the second slide mechanism 5B.

[0039] That is, in the first slide mechanism 5A, when the piston rod 51a retracts, i.e., when the piston rod 51a moves leftward, the movable part 33 slides leftward, and when the piston rod 51a advances, i.e., when the piston rod 51a moves rightward, the movable part 33 slides rightward. In the second slide mechanism 5B, when the piston rod 51a retracts, i.e., when the piston rod 51a moves rightward, the movable part 33 slides rightward, and when the piston rod 51a advances, i.e., when the piston rod 51a moves leftward, the movable part 33 slides leftward.

[0040] In this way, as the movable part 33 slides, a force F, which is an inertial force, is applied to the workpiece W placed on the upper surface 35a (see, for example, the force F shown in FIG. 9). When this force F is applied, the workpiece W on the upper surface 35a can be displaced in a direction along the upper surface 35a. As a result, for example, the upper workpiece W among the overlapping workpieces W is displaced (i.e., shifted), thereby reducing the degree of overlap of the workpieces W.

[0041] Furthermore, in this example, the mounting tables 3A and 3B are provided with an engagement portion 35b on the upper surface 35a of the jig 35. The engagement portion 35b engages when the workpiece W on the upper surface 35a is displaced in a direction along the upper surface 35a by the slide mechanisms 5A and 5B serving as the force application unit 9. In this configuration, for example, workpieces W that are in a good orientation and easy to pick, such as workpieces W that are not overlapping, can engage with the engagement portion 35b. Therefore, even workpieces W that are in a good orientation and easy to pick can be prevented from falling from the upper surface 35a.

[0042] The shape of the engaging portion 35b is determined according to the shape of the workpiece W. For example, the engaging portion 35b is set to a shape that allows the workpiece W to be caught or fitted onto the upper surface 35a when the workpiece W is displaced, thereby keeping the workpiece W on the upper surface 35a. In this example, since the workpiece W to be picked has a shape with a bent portion (see FIGS. 6 and 7), the engaging portion 35b is formed with a convex portion that the bent portion of the workpiece W can easily fit into. This convex portion is provided on the upper surface 35a of the jig 35 in the front-to-rear direction.

[0043] Furthermore, on the mounting tables 3A and 3B, a portion having an upper surface 35a on which an engaging portion 35b is provided, i.e., a jig 35, is provided so as to be freely attached and detached. In other words, the jig 35 is detachably attached to the mounting plate 34. This makes it possible to replace the jig 35 with one having an engaging portion 35b that corresponds to the shape of the workpiece W to be picked.

[0044] 5 is a block diagram of the control device 6 and its peripheral devices. The work supply device 100 further includes the control device 6. The control device 6 controls various operations of the work supply device 100. Specifically, the control device 6 controls the first air cylinder 41 to control the lifting and lowering operations of the mounting tables 3A, 3B. The control device 6 controls the second air cylinder 51 to control the sliding operation of the movable part 33. The control device 6 is capable of communicating with the robot control unit 205.

[0045] <Work supply operation> Next, the supply operation of the workpiece W picked up by the robot arm 202 in the workpiece supply device 100 configured as described above will be described with reference to FIGS. 6 to 11. The supply operation of the workpiece W is performed in the order of raising and lowering the mounting tables 3A and lowering and sliding the movable part 33. In this example, the supply operation of the workpiece W on the first mounting table 3A and the supply operation of the workpiece W on the second mounting table 3B are performed alternately. Here, the supply operation of the workpiece W on the first mounting table 3A will be described as a representative.

[0046] As shown in Figure 6, in the initial state before the supply operation of the workpieces W is started, the upper surfaces 35a of the two mounting tables 3A and 3B are located at the bottom surface 22b of the hopper 2. A plurality of workpieces W are piled up in the hopper 2. In this initial state, a plurality of workpieces W are also piled up in the upper surfaces 35a of the two mounting tables 3A and 3B. In other words, a plurality of workpieces W are piled up in layers on the upper surfaces 35a of the mounting tables 3A and 3B.

[0047] Next, the control device 6 starts the operation of supplying the workpiece W to the first mounting table 3A. That is, the control device 6 controls the first air cylinder 41 of the first lifting mechanism 4A to perform the lifting operation of the first mounting table 3A. Specifically, the control device 6 advances the piston rod 41a of the first air cylinder 41 to raise the first mounting table 3A.

[0048] As shown in Fig. 7, when the first mounting table 3A is raised, the plurality of workpieces W on the upper surface 35a of the first mounting table 3A are lifted. At this time, as indicated by the dashed arrows in Fig. 7, some of the workpieces W on the upper surface 35a of the first mounting table 3A slide off the upper surface 35a. As a result, the number of workpieces W on the upper surface 35a of the first mounting table 3A decreases, and the degree of overlap of the workpieces W is reduced.

[0049] Then, when the upper surface 35a of the first mounting table 3A rises to the picking position P, the lifting operation (more specifically, the lifting operation) of the first mounting table 3A ends. That is, the control device 6 stops the first air cylinder 41. As shown in FIG. 8, the degree of overlap of the workpieces W on the upper surface 35a of the first mounting table 3A that has risen to the picking position P has decreased compared to before the lifting operation, but it may still not be sufficient.

[0050] Next, the control device 6 controls the second air cylinder 51 of the first slide mechanism 5A to perform a sliding operation of the movable part 33. Specifically, the control device 6 causes the piston rod 51a of the second air cylinder 51 to retract, thereby sliding the movable part 33 to the left.

[0051] As shown in FIG. 9, as the movable part 33 slides leftward, a force F, which is an inertial force, acts on the workpiece W on the upper surface 35a of the first mounting table 3A in the direction opposite to the sliding direction of the movable part 33 (i.e., rightward). As a result, the workpiece W on the upper surface 35a can be displaced in the direction in which the force F acts. Then, when the movable part 33 slides a predetermined distance, the sliding movement of the movable part 33 temporarily ends. In other words, the control device 6 stops the second air cylinder 51. As shown in FIG. 10, as the sliding movement of the movable part 33 is stopped, a force F, which is an inertial force, acts on the workpiece W on the upper surface 35a of the first mounting table 3A in the direction in which the movable part 33 was sliding (i.e., leftward). As a result, the workpiece W on the upper surface 35a can be displaced in the direction in which the force F acts.

[0052] In this way, by displacing the workpieces W on the upper surface 35a in a direction along the upper surface 35a by sliding and stopping the movable part 33, for example, the upper workpiece W of overlapping workpieces W slides off from the lower workpiece W. Therefore, for example, as with workpiece Wb shown in FIG. 11, a workpiece from which the overlap has been resolved can be placed on the upper surface 35a. Furthermore, as with workpiece Wa shown in FIGS. 10 and 11, by engaging with the engaging part 35b, a workpiece that does not overlap with other workpieces W can be held on the upper surface 35a without falling from the upper surface 35a. In this way, the degree of overlap of workpieces W on the upper surface 35a is significantly reduced.

[0053] In this way, when the sliding movement of the movable part 33 is completed, the workpiece W placed on the upper surface 35a is picked up by the robot arm 202. At this time, the degree of overlap of the workpieces W on the upper surface 35a is reduced, that is, the proportion of workpieces W on the upper surface 35a that are not overlapped with other workpieces W is increased, which improves the ease of picking by the robot arm 202.

[0054] In particular, since the workpiece Wa engaged with the engaging portion 35b is present on the upper surface 35a, the ease of picking is further increased. The workpiece Wa engaged with the engaging portion 35b is positioned in the left-right direction and held in a fixed posture, which simplifies the control of the operation of the robot arm 202 during picking. Therefore, the ease of picking by the robot arm 202 is further increased.

[0055] Then, when there are no more pickable workpieces W on the upper surface 35a, the control device 6 slides the movable part 33 back to its original state. For example, when the robot control unit 205 determines that there are no pickable workpieces W on the upper surface 35a based on the image captured by the camera 204, it outputs a determination signal to the control device 6. This causes the control device 6 to recognize that there are no pickable workpieces W on the upper surface 35a. Specifically, the control device 6 advances the piston rod 51a of the second air cylinder 51, thereby sliding the movable part 33 to the right. At this time, as shown in FIG. 12 , the workpieces Wc that have fallen from the upper surface 35a onto the table main body 31 are dropped from the table main body 31.

[0056] When the movable part 33 slides back to its original state in this way, the control device 6 lowers the first mounting table 3A to return it to its initial state. This completes the operation of supplying the workpiece W to the first mounting table 3A. Next, the control device 6 starts the operation of supplying the workpiece W to the second mounting table 3B. The operation of supplying the workpiece W to the second mounting table 3B is the same as the operation of supplying the workpiece W to the first mounting table 3A described above.

[0057] As described above, the workpiece supply device 100 includes the hopper 2, the placement tables 3A and 3B, and the lifting mechanisms 4A and 4B. The hopper 2 is open at the top and accommodates a plurality of workpieces W. The placement tables 3A and 3B have an upper surface 35a that forms part of the bottom surface 22b of the hopper 2, and the workpieces W located on the upper surface 35a are picked up by the robot arm 202. The lifting mechanisms 4A and 4B raise and lower the placement tables 3A and 3B so that the upper surface 35a moves between the position of the bottom surface 22b and a predetermined picking position P for the robot arm 202 that is higher than the bottom surface 22b.

[0058] According to the above configuration, when the upper surfaces 35a of the mounting tables 3A and 3B are positioned at the bottom surface 22b of the hopper 2, multiple workpieces W are stacked on the upper surfaces 35a of the mounting tables 3A and 3B. When the mounting tables 3A and 3B are raised from this state by the lifting mechanisms 4A and 4B, the multiple workpieces W on the upper surfaces 35a of the mounting tables 3A and 3B are lifted, and some of the workpieces W on the upper surfaces 35a slide off the upper surfaces 35a. Therefore, the number of workpieces W on the upper surfaces 35a of the mounting tables 3A and 3B that have risen to the picking position P is reduced, and the degree of overlap of the workpieces W can be reduced. This makes it easier for the robot arm 202 to recognize the position and posture of the workpieces W on the upper surfaces 35a. Therefore, even when multiple workpieces W are stored in the hopper 2 in a loose pile, the ease of picking by the robot arm 202 can be improved.

[0059] In addition, the work supply device 100 further includes a force application unit 9 that applies a predetermined force to the work W on the upper surface 35a that has moved to the picking position P, thereby displacing the work W on the upper surface 35a in a direction along the upper surface 35a.

[0060] According to the above configuration, the workpieces W on the upper surface 35a that have risen to the picking position P are displaced in a direction along the upper surface 35a, so that, for example, among the overlapping workpieces W, the upper workpiece W slides off from the lower workpiece W. This eliminates the overlap of the workpieces W, and the degree of overlap of the workpieces W on the upper surface 35a can be further reduced. This further improves the ease of picking by the robot arm 202.

[0061] Moreover, in the work supply device 100, the mounting tables 3A, 3B have a table main body 31 and a movable part 33 that has an upper surface 35a and is provided above the table main body 31 so as to be slidable in a direction along the upper surface 35a. The work supply device 100 has, as the force applying unit 9, slide mechanisms 5A, 5B that slide the movable part 33 when the upper surface 35a moves to the picking position P.

[0062] According to the above configuration, the inertial force generated by sliding the movable part 33 can be applied to the workpiece W on the upper surface 35a, thereby displacing the workpiece W on the upper surface 35a in a direction along the upper surface 35a.

[0063] Furthermore, the upper surfaces 35a of the mounting tables 3A and 3B are provided with engaging portions 35b that engage when the workpiece W on the upper surfaces 35a is displaced by the force applying portion 9 in a direction along the upper surfaces 35a.

[0064] According to the above configuration, when the workpiece W is displaced in a direction along the upper surface 35a, it engages with the engaging portion 35b on the upper surface 35a, thereby preventing the workpiece W from falling off the upper surface 35a. Therefore, workpieces W in a good posture that are particularly easy to pick can be retained on the upper surface 35a, further increasing the ease of picking. Furthermore, by the workpiece W engaging with the engaging portion 35b, it becomes possible to position the workpiece W to a certain extent on the upper surface 35a and to hold the workpiece W in a constant posture. This also increases the ease of picking.

[0065] Further, the mounting tables 3A and 3B are provided with a portion having an upper surface 35a on which the engaging portion 35b is provided, that is, a jig 35, which is detachably provided.

[0066] According to the above-described configuration, the jig 35 can be easily replaced with one having an engaging portion 35b that corresponds to the shape of the workpiece W. Therefore, the ease of picking can be effectively improved.

[0067] Two sets of mounting tables 3A, 3B and lifting mechanisms 4A, 4B are provided.

[0068] According to the above configuration, for example, while the first lifting mechanism 4A is lifting and lowering the first mounting table 3A to supply the workpiece, the second lifting mechanism 4B can be prepared to lift and lower the second mounting table 3B, thereby improving the efficiency of supplying the workpiece W to the robot arm 202.

[0069] Other Embodiments As described above, the above embodiment has been described as an example of the technology disclosed in this application. However, the technology of the present disclosure is not limited to this and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate. Furthermore, the components described in the above embodiment can be combined to create new embodiments. Furthermore, the components described in the accompanying drawings and detailed description may include not only components essential for solving the problem, but also components that are not essential for solving the problem in order to exemplify the technology. Therefore, the fact that these non-essential components are described in the accompanying drawings or detailed description should not be interpreted as immediately determining that these non-essential components are essential.

[0070] 13 is a view corresponding to FIG. 9, showing a work supply device 100 according to another embodiment. For example, in the work supply device 100 according to the embodiment, a gas blowing mechanism 7 may be provided as the force applying unit 9 in addition to the slide mechanisms 5A and 5B. Note that while FIG. 13 illustrates the gas blowing mechanism 7 for the first mounting table 3A, the gas blowing mechanism for the second mounting table 3B is not illustrated.

[0071] The gas blowing mechanism 7 blows air in a direction along the upper surface 35a toward the workpiece W on the upper surface 35a that has moved to the picking position P. Air is an example of a gas. Specifically, the gas blowing mechanism 7 has a blowing unit 71 and a supply pipe 72. The blowing unit 71 is connected to the supply pipe 72 and blows out air sent from the supply pipe 72. The gas blowing mechanism 7 is configured to blow air in a direction opposite (to the right in this example) to the sliding direction (to the left in this example) of the movable part 33 when the movable part 33 slides due to the first slide mechanism 5A. In other words, the gas blowing mechanism 7 blows air in the same direction as the acting direction of the inertial force generated when the movable part 33 slides due to the slide mechanisms 5A and 5B.

[0072] Therefore, in this embodiment, the force F applied to the workpieces W on the upper surface 35a is a combined force of the inertial force generated by the sliding movement of the movable part 33 and the force of the air blown out by the gas blowing mechanism 7. As a result, the force F applied to the workpieces W increases, and the workpieces W on the upper surface 35a can be reliably displaced in a direction along the upper surface 35a. This further reduces the degree of overlap of the workpieces W on the upper surface 35a, further improving the ease of picking.

[0073] Furthermore, in the workpiece supply device 100 of the above embodiment, instead of the slide mechanisms 5A and 5B, a gas blowing mechanism 7 may be provided as the force applying unit 9. In this case, the direction in which air is blown by the gas blowing mechanism 7 may be any direction as long as the air is blown in a direction along the upper surface 35a toward the workpiece W on the upper surface 35a.

[0074] Furthermore, in the work supply device 100 of the above embodiment, a convex portion is provided as the engaging portion 35b, but other shapes may also be used. For example, if the shape of the work W to be picked has a convex portion, a concave portion may be provided as the engaging portion 35b. In other words, the shape of the engaging portion 35b is set so that it can, for example, be caught or fitted into when the work W is displaced in a direction along the upper surface 35a.

[0075] Furthermore, in the workpiece supplying device 100 of the above embodiment, only one set of the mounting table, the lifting mechanism, and the slide mechanism may be provided.

[0076] In addition, in the work supply device 100 of the above embodiment, the slide mechanisms 5A and 5B may be omitted.

[0077] Furthermore, in the work supply device 100 of the above embodiment, if the work W can be sufficiently prevented from falling off the upper surface 35a due to the sliding movement of the movable part 33, the engaging part 35b may be omitted.

[0078] In the workpiece supplying device 100 of the above embodiment, the first air cylinder 41 and the second air cylinder 51 may be hydraulic cylinders or the like.

[0079] Furthermore, the number of times that the slide mechanisms 5A, 5B slide the movable parts 33 of the mounting tables 3A, 3B is not limited to one, but may be multiple times. In other words, the slide mechanisms 5A, 5B may move the movable parts 33 back and forth in the left and right direction multiple times.

[0080] Furthermore, the lifting mechanisms 4A, 4B may raise and lower the hopper 2 instead of the mounting tables 3A, 3B. In other words, the lifting mechanisms 4A, 4B may raise and lower the bottom surface 22b of the hopper 2 so that the upper surfaces 35a of the mounting tables 3A, 3B move relatively between the position of the bottom surface 22b and the picking position P. [Explanation of symbols]

[0081] 100 Work supply device 2 Hopper (container) 22b Bottom 3A First stage (stage) 3B Second stage (stage) 31 unit body 33 Moving parts 35a top side 35b Engagement part 4A First lifting mechanism (lifting mechanism) 4B Second lifting mechanism (lifting mechanism) 5A First slide mechanism (slide mechanism) 5B Second slide mechanism (slide mechanism) 7 Gas blowing mechanism 9 Force applying section double work P Picking position

Claims

1. A container having an open top and capable of accommodating a plurality of workpieces; a mounting table having an upper surface that forms a part of the bottom surface of the container, and on which a workpiece positioned on the upper surface is picked up by a robot arm; a lifting mechanism that lifts and lowers the container or the placement table so that the top surface moves relatively between the position of the bottom surface and a predetermined picking position by the robot arm that is higher than the bottom surface; a force applying unit that applies a predetermined force to the workpiece on the upper surface that has moved relatively to the picking position, thereby displacing the workpiece on the upper surface in a direction along the upper surface, the mounting table includes a table body and a movable part having the upper surface and provided above the table body so as to be slidable in a direction along the upper surface, The force applying unit has a slide mechanism that slides the movable unit when the upper surface moves relatively to the picking position.

2. The workpiece supply device according to claim 1, The force applying unit is a work supply device having a gas blowing mechanism that blows gas in a direction along the upper surface toward the work on the upper surface that has moved relatively to the picking position.

3. The work supply device according to claim 1 or 2, The work supply device has an engaging portion on the upper surface that engages with the work on the upper surface when the work on the upper surface is displaced in a direction along the upper surface by the force applying portion.

4. The workpiece supply device according to claim 3, In the work supply device, a portion of the mounting table having the upper surface on which the engaging portion is provided is detachably provided.

5. The workpiece supply device according to claim 1, The work supply device has two sets of the mounting table and the lifting mechanism.

6. A work supply method for supplying a work to be picked up by a robot arm, comprising: With the top surface of the mounting table positioned at the bottom surface of the container, a plurality of workpieces are placed in the container and the workpieces are placed on the top surface; Relatively moving the top surface from the position of the bottom surface to a predetermined picking position by the robot arm that is higher than the bottom surface; When the upper surface has moved relatively to the picking position, a movable part of the placement table having the upper surface is slid in a direction along the upper surface. and after sliding the movable part, picking up the workpiece placed on the upper surface by the robot arm.

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