Component holding device

Abstract

The element gripping device (10) of the present disclosure includes a hand (30) having a plurality of gripping portions (31) for gripping an element (P) that is a magnetic body, a picking robot (20) for transferring the element (P) gripped by the hand (30), and a control unit (50) for adjusting the magnetic force of the hand (30). Since the magnetic force of the hand (30) can be adjusted by the control unit (50), a wide variety of gripping objects can be accurately gripped.

Description

Technical Field

[0001] This disclosure relates to a component holding device. Background Technology

[0002] Conventionally, a workpiece transfer device described in International Publication No. 2017 / 094112 is known as a device for picking up and placing workpieces. This workpiece transfer device has an attraction section at the front end of a shaft member that attracts and picks up a workpiece that is magnetic, and a clamping section that holds and supports the workpiece in the attracted position. The shaft member of the attraction section is connected to an electromagnet, and multiple levels of magnetic force (attraction force) are generated in the attraction section according to the power supplied to the electromagnet.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2017 / 094112 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In the workpiece transfer device described above, the attraction part and the clamping part are separate, making it impossible for the clamping part itself to generate magnetic force. Since the clamping part is responsible for holding the components, it needs to be designed to fit the shape of the components, requiring a special clamping part for each component. Furthermore, in the workpiece transfer device described above, only one workpiece can be clamped by the clamping part, thus preventing the clamping of multiple workpieces at once. This also limits the device's versatility in handling various clamping methods, such as accurately holding diverse objects of different sizes, weights, and quantities.

[0008] Methods for solving problems

[0009] The component holding device disclosed herein includes: a hand having a plurality of holding parts for holding a component that is a magnetic body; a picking robot for transferring the component held by the hand; and a control unit for adjusting the magnetic force of the hand.

[0010] Invention Effects

[0011] According to this disclosure, the magnetic force of the hand can be adjusted by the control unit, thus enabling accurate gripping of a wide variety of objects. Attached Figure Description

[0012] Figure 1 This is the front view of the component holding device.

[0013] Figure 2 This is a block diagram of the component holding device.

[0014] Figure 3 This is the front view of the hand.

[0015] Figure 4 It is a bottom view of the hand.

[0016] Figure 5 This is an operational diagram illustrating the component holding device of Embodiment 1.

[0017] Figure 6 This is a flowchart of the component holding device according to Embodiment 1.

[0018] Figure 7 This is an operational illustration of the component holding device in Embodiment 2-1.

[0019] Figure 8 This is a flowchart of the component holding device in embodiment 2-1.

[0020] Figure 9 This is an operational illustration of the component holding device in Embodiment 2-2.

[0021] Figure 10 This is a flowchart of the component holding device in embodiment 2-2.

[0022] Figure 11 This is an operational illustration of the component holding device in Embodiment 3.

[0023] Figure 12 This is a flowchart of the component holding device in Embodiment 3. Detailed Implementation

[0024] [Description of embodiments of this disclosure]

[0025] First, the implementation schemes disclosed herein are listed and explained.

[0026] (1) The component holding device disclosed herein is a component holding device comprising: a hand having a plurality of holding parts for holding a component as a magnetic body by means of the plurality of holding parts; a picking robot for transferring the component held by the hand; and a control unit for adjusting the magnetic force of the hand.

[0027] Since the magnetic force of the hand can be adjusted through the control unit, the magnetic force is used to attract or bounce back the components, thereby allowing any number of components to be held.

[0028] (2) Preferably, the control unit establishes an association between the magnetic force and the number information by obtaining the number information of the held elements.

[0029] By obtaining information on the number of components being manipulated, the control unit can establish a correlation between the magnetic force and the number of components.

[0030] (3) Preferably, the control unit adjusts the hand width, which is the interval between the plurality of gripping parts.

[0031] The hand width can be adjusted via the control unit, so that multiple types of components of different sizes can be held with the same hand.

[0032] (4) Preferably, the control unit establishes an association between the magnetic force, the hand width and the number of elements held by obtaining the number of elements held.

[0033] By obtaining information on the number of components being held, the control unit can establish a correlation between magnetic force, hand width, and the number of components.

[0034] (5) The width of the hand is the interval between a pair of opposite gripping parts.

[0035] Since only the spacing between the two opposing grips needs to be adjusted, it is easy to adjust the hand width.

[0036] (6) Preferably, the control unit includes: a magnetic force adjustment unit for adjusting the magnetic force of the hand; a hand width adjustment unit for adjusting the hand width; a calculation unit for establishing an association between the magnetic force, the hand width and the number information; and a storage unit for storing the associated magnetic force, the hand width and the number information.

[0037] The arithmetic unit can establish a correlation between magnetic force, hand width, and number of items, and store this correlation in the storage unit to control the magnetic force and hand width for a high success rate of gripping. Furthermore, it can learn and control magnetic force and hand width for even higher success rates in this way.

[0038] (7) Preferably, the hand has the plurality of gripping portions as magnetic bodies and a coil for magnetizing the gripping portions.

[0039] By magnetizing the holding part with a coil, the holding part itself has magnetic force, thereby enabling reliable holding and transfer of components.

[0040] (8) Preferably, the control unit is configured to use a strong magnetic force to magnetize the gripping part for the element with a large mass, and to use a weak magnetic force to magnetize the gripping part for the element with a small mass.

[0041] If a strong magnetic force is used on a small component, it will exceed the required attraction, potentially causing the component to fall during transport. Therefore, by using an appropriate magnetic force corresponding to the component's mass, as described above, the required number of components can be attracted, thus improving the success rate of handling.

[0042] (9) Preferably, the hand grasps the element after attracting it to the element placed on the mounting portion by magnetizing the plurality of gripping portions.

[0043] Even when there are components in hard-to-hold areas, such as the end of the tray's mounting section, the components can be attracted to a holdable position and then held.

[0044] (10) Preferably, the hand is configured to attract the element placed on the mounting portion to each of the grip portions by magnetizing the plurality of grip portions in an open state, and then grips the element by closing the plurality of grip portions to gather the element together in one place.

[0045] When components are arranged in a scattered state on the tray's mounting section, the success rate of gripping may be low. Even in this case, it is possible to arrange the components to attract each gripping section, and by closing multiple gripping sections, the components are gathered in one place, thereby improving the success rate of gripping.

[0046] (11) Preferably, the hand holds multiple elements with a magnetic force greater than that used to hold a single element.

[0047] Multiple components can be held without changing the hands or disposing of the components.

[0048] [Details of Embodiment 1 of this disclosure]

[0049] [Overall structure of the component holding device]

[0050] Reference Figure 1 The overall structure of the component holding device 10 will be described. The component holding device 10 is a device for taking out a portion of the components P from a box containing a large number of components P and dividing them into smaller parts. The component holding device 10 includes a picking robot 20 for holding and transferring components P, a camera 40 for photographing objects such as components P, etc.

[0051] [Structure of the pickup robot]

[0052] The picking robot 20 has a vertically articulated robotic arm 21 and a hand 30 mounted on the front end of the robotic arm 21 to grasp the component P. The hand 30 is sometimes referred to as an end effector. The robotic arm is not limited to a vertically articulated type; it can also be a SCARA robot (horizontal articulated robot) or other types of robots.

[0053] The robotic arm 21 has a base portion 23 fixed to a support 22 and multiple links 24 for transmitting displacement and force. The base portion 23, the links 24, and adjacent links 24 are connected to each other by joints 25 to enable swinging or rotation. In this embodiment, the robotic arm 21 has joints 25 with three swing axes and six rotation axes, and a joint drive device (not shown) is assembled in each joint 25.

[0054] [Structure of the hand]

[0055] The hand 30 has multiple gripping portions 31 for gripping the element P. In this embodiment, the element P is clamped and held by a pair of gripping portions 31. The hand 30 is mounted on a connecting rod 24 located at the end opposite to the base portion 23. The pair of gripping portions 31 can be displaced in a direction that approaches and separates from each other. The element P is gripped by moving the pair of gripping portions 31 in parallel in the direction that approaches each other (closing action), and the element P is released by moving the pair of gripping portions 31 in parallel in the direction that separates from each other (opening action).

[0056] In detail, the hands 30 Figure 3 as well as Figure 4 As shown, it includes a pair of grip sections 31, a coil 32, and a hand body section 33. The pair of grip sections 31 are arranged in two rows extending downwards from the hand body section 33, and are configured opposite each other in the opening and closing direction. A coil 32 is disposed at the end of the pair of grip sections 31 on the hand body section 33 side. The coil 32 is arranged to surround the two grip sections 31.

[0057] The gripping part 31 is made of a magnetic material and is magnetized (possessing magnetic force) by a magnetic field generated by flowing current into the coil 32. The direction of the magnetic field can be controlled by the direction of the current flowing into the coil 32, and the strength of the magnetic force can be controlled by the intensity of the current flowing into the coil 32. Adjustments to the strength of the magnetic force and the width of the grip can be performed before, during, and after the picking operation. The picking operation includes the operation of gripping the element P through a pair of gripping parts 31 and the operation of transferring the gripped element P by the picking robot 20. The width of the grip refers to the distance between the opposing pair of gripping parts 31 (the distance between a pair of opposing surfaces 34).

[0058] In the absence of a hand with coil 32, when holding component P by a pair of gripping parts, the component P is fixed by the frictional force generated between the gripping parts and component P. Therefore, sufficient frictional force cannot be obtained if the contact area between the gripping parts and component P cannot be sufficiently ensured. In this regard, the hand 30 of this disclosure is equipped with coil 32, which uses magnetic force to fix component P, thus increasing the variety of components P that can be grasped with the same gripping part 31.

[0059] Furthermore, for components P with relatively large mass, a strong magnetic force is used to magnetize the holding part 31 and hold and move the component P; for components P with relatively small mass, a weak magnetic force is used to magnetize the holding part 31 and hold and move the component P. In this way, the attraction of relatively small mass components P will not exceed what is needed, and components P that are fixed to the side of the holding part 31 by magnetic force (excluding the opposing surface 34) can be prevented from falling during the transfer.

[0060] [Camera Structure]

[0061] Camera 40 is a device for capturing images of element P, and includes photoelectric conversion elements such as CCD and CMOS, and a light source for illuminating element P. Camera 40 outputs an image signal, which has undergone photoelectric conversion by the photoelectric conversion elements, to control unit 50 (described later). When capturing images of element P held by hand 30, for example, control unit 50 can obtain information such as the type and number of element P by performing image processing on the image signal. Camera 40 is mounted on a different component than the picking robot 20 (e.g., a ceiling wall, not shown, positioned above support 22).

[0062] [Electrical structure of component holding device]

[0063] Next, refer to Figure 2 A block diagram is provided, and the electrical structure of the component holding device 10 is described. The component holding device 10 has a control unit 50, which provides comprehensive control of the entire device. The control unit 50 includes a holding position estimation unit 51, a magnetic force adjustment unit 52, a hand width adjustment unit 53, a calculation unit 54, and a storage unit 55. A picking robot 20, a hand 30, and a camera 40 are connected to the control unit 50. The movements of the picking robot 20, the hand 30, and the camera 40 are all controlled by the control unit 50.

[0064] The gripping position estimation unit 51 estimates the position of element P based on the image of element P captured by camera 40. For example, the center position of the image is preset as the position of the camera, and since the position of the camera is known, the position of element P is estimated by measuring the offset of element P from the center position of the image. As a result, the control unit 50 controls the movement of the robot arm 21 in such a way that the center of the pair of gripping units 31 moves toward the position of element P.

[0065] The magnetic force adjustment unit 52 adjusts the intensity of the magnetic force generated in the coil 32 by adjusting the intensity of the current flowing into the coil 32. The intensity of the magnetic force is determined by the mass calculated based on the number of elements P. Furthermore, the magnetic force adjustment unit 52 adjusts the orientation of the magnetic field generated in the coil 32 by adjusting the orientation of the current flowing into the coil 32. By changing the orientation of the magnetic field, elements P can be attracted or repelled.

[0066] The hand width adjustment unit 53 adjusts the hand width according to the type of component P. The size of component P is known, so the hand width can be determined according to the type of component P.

[0067] The arithmetic unit 54 establishes a correlation between the magnetic force, hand width, and number information, and stores this correlation in the storage unit 55. Furthermore, the arithmetic unit 54 calculates the overall mass of component P based on the mass of each component P and the number of components P. Moreover, the arithmetic unit 54 accesses the storage unit 55 to obtain information such as the magnetic force and hand width corresponding to the number of components P (overall mass).

[0068] Storage unit 55 stores a chart that associates the component name of component P with the width of the hand (hereinafter referred to as "hand width and component chart") 56, a chart that associates the component name of component P with the mass (hereinafter referred to as "component mass") 57, and a chart that associates the mass with the magnetic force (electricity) (hereinafter referred to as "magnetic force and mass chart") 58.

[0069] [Operational Description of the Component Holding Device]

[0070] Next, refer to Figure 5 The diagram illustrates the operation of the component holding device 10 and explains its operation. Figure 5 (A) shows the case where the element P, which is placed in the mounting part 61 of the tray 60, is held while the element SP, which is of small mass, is being held. Figure 5 (B) shows the case where the element P, which is placed in the mounting section 61 of the tray 60, is held while the element LP, which has a larger mass, is being held. Both the small element SP and the large element LP are magnetic. The small element SP is smaller and lighter than the large element LP. The hand width required to hold the small element SP is smaller than the hand width required to hold the large element LP. Furthermore, the magnetic force used to hold the small element SP is weaker than the magnetic force used to hold the large element LP.

[0071] For example, if the smaller component SP is an M3 bolt and the larger component LP is an M6 bolt, the hand width when holding the smaller component SP can be 5mm, and the hand width when holding the larger component LP can be 8mm. Furthermore, if the smaller component SP has a mass of 1g and the larger component LP has a mass of 5g, and the magnetic force (electricity) when holding the smaller component SP is 20W, the magnetic force (electricity) when holding the larger component LP can be 100W, which is greater.

[0072] Specifically, the arithmetic unit 54 can determine the hand width by accessing the storage unit 55 and referring to the hand width and component diagram 56. Furthermore, the arithmetic unit 54 can also determine the mass of each component by accessing the storage unit 55 and referring to the component mass 57, calculating the overall mass of component P based on the number of components P and the mass of each component. Additionally, the arithmetic unit 54 can also determine the magnetic force corresponding to the overall mass of component P by accessing the storage unit 55 and referring to the magnetic force and mass diagram 58.

[0073] Thus, by adjusting the hand width according to the type of component P (small component SP, large component LP, etc.), multiple types of components P can be held using the same hand 30. Needless to say, it is not limited to the small component SP and large component LP exemplified above; any size of component P can be held as long as the hand width can be adjusted. Furthermore, by using magnetic force when holding component P, component P can be held more reliably, reducing the probability of component P falling during transport.

[0074] However, when using a strong magnetic force to hold a small component SP, it may be necessary to attract more small components SP than needed, and it may be possible to hold multiple components SP. Therefore, it is preferable to use a weak magnetic force.

[0075] [Operating steps of the component holding device]

[0076] Next, refer to Figure 6 The flowchart and operation steps of the component holding device 10 are explained. First, the camera 40 captures an image of the component P placed in the mounting section 61, and the holding position estimation unit 51 estimates the holding position of the component P, causing the hand 30 to move towards that holding position (step S1). Next, the calculation unit 54 accesses the storage unit 55 and determines the hand width by referring to the hand width and component chart 56 (step S2). Next, the hand width adjustment unit 53 moves the two holding sections 31 so that the interval between the pair of holding sections 31 is the hand width determined in step S2. Next, the calculation unit 54 accesses the storage unit 55 and refers to the component mass 57 (step S4), and also refers to the magnetic force and mass chart 58 (step S5). The calculation unit 54 determines the magnetic force based on the reference results of steps S4 and S5 (step S6).

[0077] Next, the magnetic force adjustment unit 52 activates the magnetic force determined in step S6 (step S7). Then, the two gripping units 31 grip the component P (step S8), and the robot arm 21 picks up the component P (step S9). Next, the magnetic force is deactivated or reversed by the magnetic force adjustment unit 52 (step S10), causing the component P (which is not gripped and is fixed only by magnetic force on surfaces other than the opposing surface 34) to fall under its own weight. Next, the magnetic force adjustment unit 52 activates a stronger magnetic force than in step S6 (step S11), making it difficult to drop the component P during component transfer.

[0078] Next, the robot arm 21 transfers component P to another mounting section (step S12). Then, the hand 30 opens (step S13), releasing component P, and the magnetic force adjustment section 52 disconnects or reverses the magnetic force when the robot arm 21 mounts component P (step S14), thereby reliably releasing component P from the holding section 31.

[0079] [Effects of Implementation Method 1]

[0080] As described above, the component holding device 10 disclosed herein includes: a hand 30 having a plurality of holding parts 31 for holding a component P, which is a magnetic body, by means of the plurality of holding parts 31; a picking robot 20 for transferring the component P held by the hand 30; and a control unit 50 for adjusting the magnetic force of the hand 30.

[0081] Since the magnetic force of the hand 30 can be adjusted by the control unit 50, the magnetic force can be used to attract or bounce back the element P, thereby enabling the holding of any number of elements P.

[0082] In this way, it can cope with a variety of control schemes and accurately control a variety of control objects of different quantities.

[0083] Preferably, the control unit 50 establishes a correlation between the magnetic force and the number of elements P it holds by obtaining the number of elements P held.

[0084] By obtaining the number of elements P being held, the control unit 50 can establish a correlation between the magnetic force and the number of elements.

[0085] Preferably, the control unit 50 adjusts the hand width, which is the spacing between the plurality of gripping parts 31.

[0086] The width of the hand can be adjusted by the control unit 50, so that the same hand 30 can be used to hold small components SP and large components LP.

[0087] This improves the versatility of the hand 30, enabling it to accurately grasp a wide variety of objects of different sizes.

[0088] Preferably, the control unit 50 establishes a correlation between the magnetic force, hand width, and number of elements P by obtaining the number of elements P being held.

[0089] By obtaining the number of components P being held, the control unit 50 can establish a correlation between the magnetic force, hand width, and the number of components.

[0090] The width of the hand can be the interval between a pair of opposing gripping parts 31.

[0091] Since only the spacing between the two opposing grip sections 31 needs to be adjusted, the hand width can be easily adjusted.

[0092] The control unit 50 includes: a magnetic force adjustment unit 52 for adjusting the magnetic force of the hand 30; a hand width adjustment unit 53 for adjusting the hand width; a calculation unit 54 for establishing a correlation between the magnetic force, hand width, and number information; and a storage unit 55 for storing the established correlation between the magnetic force, hand width, and number information.

[0093] The arithmetic unit 54 can establish a correlation between magnetic force, hand width, and number of items, and store this correlation in the storage unit 55 to control the magnetic force and hand width for a high success rate of holding the item. Furthermore, in this way, it is also possible to learn and control magnetic force and hand width for even higher success rates of holding the item.

[0094] The hand part 30 has multiple gripping parts 31 that are magnetic bodies and a coil 32 that magnetizes the gripping parts 31.

[0095] The holding part 31 is magnetized by the coil 32, so that the holding part 31 itself has magnetic force, thereby enabling reliable holding and transfer of the component P.

[0096] The magnetic force adjustment unit 52 of the control unit 50 is configured to use a strong magnetic force to magnetize the holding part 31 for the component LP with a large mass, and to use a weak magnetic force to magnetize the holding part 31 for the component SP with a small mass.

[0097] If a strong magnetic force is used on a small component SP, the force will exceed the required attraction, potentially causing the small component SP to be dropped during component transfer. Therefore, by using an appropriate magnetic force corresponding to the mass of component P, as described above, the required number of components P can be attracted, thus improving the success rate of holding the component.

[0098] By performing the procedure as described in Embodiment 1, it is possible to accurately grasp a wide variety of objects that differ in size, weight, or quantity.

[0099] [Details of Embodiment 2-1 of this disclosure]

[0100] Next, refer to Figure 7 as well as Figure 8 The present disclosure will now describe an embodiment 2-1. Embodiment 2-1 describes a method for moving and unloading an element P when it is present at the corner of the tray 60 (the end of the mounting portion 61) and the element P cannot be grasped by hand or unloaded by hand. The method involves magnetizing the hand 30 and attracting the element P to a position that can be grasped by the hand 30.

[0101] [Operational Description of the Component Holding Device]

[0102] Figure 7 (A) shows a case where element P is placed at a corner of tray 60. When element P is placed at the end of the placement portion 61, even if the hand 30 is moved to the end of tray 60 and the pair of grip portions 31 are opened, element P cannot be gripped by the pair of grip portions 31. Therefore, Figure 7 (B) shows the case where the element P is attracted to the holding part 31 by magnetic force alone, by flowing current to the coil 32 and turning on the magnetic force of the holding part 31. Figure 7 (C) shows the situation where the pair of grips 31 are closed and the hand 30 is moved to the center of the tray 60 while the element P is being attracted to the grip 31. Figure 7 (D) shows the state in which the hand 30 is moved upward and the pair of grips 31 are opened to a hand width corresponding to the type of element P after the magnetic force of the grip 31 is disconnected and the element P is released.

[0103] [Operating steps of the component holding device]

[0104] Next, refer to Figure 8 The flowchart and operating steps of the component holding device 10 are explained. First, the component P is identified as difficult to hold by the hand 30 by taking a picture of the component P with the camera 40 (step S210). Next, the pair of holding parts 31 of the hand 30 are opened to form a state in which one of the holding parts 31 is as close as possible to the component P (step S211). Next, the magnetic force is determined by accessing the storage unit 55 through the arithmetic unit 54 and referring to the magnetic force and mass chart 58 (step S212).

[0105] Next, the magnetic force adjustment unit 52 activates the magnetic force determined in step S212 (step S213). This attracts the element P from the end of the mounting portion 61 to the gripping portion 31 via magnetic force. After the element P is in contact with the gripping portion 31, it is moved towards a position where the element P can be gripped (e.g., the center of the mounting portion 61) by closing the pair of gripping portions 31 of the hand 30 or by moving the robot arm 21 (step S214). Then, the magnetic force is deactivated by the magnetic force adjustment unit 52, releasing the element P from the gripping portion 31 (step S215).

[0106] Next, the hand 30 is moved upwards towards the component P (step S216), and the gripping position estimation unit 51 estimates the gripping position of the component P by taking a picture of the component P with the camera 40 (step S217). Next, the pair of gripping portions 31 of the hand 30 are opened to a hand width that allows gripping of the component P, and the hand 30 is moved to a height position of the mounting portion 61. If the component P is positioned between the pair of gripping portions 31, the component P is gripped by closing the pair of gripping portions 31 (step S218). Next, the component P is picked up by moving the hand 30 upwards (step S219).

[0107] [Effects of Implementation Method 2-1]

[0108] As described above, the hand 30 of this disclosure grasps the element P after attracting it to the element P placed on the mounting portion 61 by magnetizing the plurality of gripping portions 31.

[0109] Even if the component P is located in a difficult-to-hold part, such as the end of the mounting portion 61 of the tray 60, the component P can be attracted to a position where it can be held and then held.

[0110] [Details of Embodiment 2-2 of this disclosure]

[0111] Next, refer to Figure 9 as well as Figure 10 The following describes embodiment 2-2 of the present disclosure. Embodiment 2-2 describes a method in which, when multiple elements P are arranged thinly and flat, the hand 30 is closed while the gripping width of the elements P is larger and the magnetic force is stronger. This increases the success rate of gripping by creating a stack of elements P by bringing the multiple elements P together in one place.

[0112] [Operational Description of the Component Holding Device]

[0113] Figure 9 (A) shows a case where multiple thin and flat components P are placed in the mounting section 61 of the tray 60. It can be seen that if the component P is to be held by hand 30 in this state, it is sometimes impossible to hold the component P, resulting in a low success rate. Therefore, Figure 9 (B) shows a case in which multiple elements P are attracted to a pair of grippers 31 by magnetic force alone, by flowing current into coil 32 and connecting the magnetic force of a pair of grippers 31. Figure 9 (C) shows a case in which multiple elements P are brought together in one place by closing a pair of gripping parts 31. Figure 9 (D) shows a case in which the pile of element P is manufactured by moving the hand 30 upward after the magnetic force of the gripping part 31 is disconnected and the element P is released.

[0114] [Operating steps of the component holding device]

[0115] Next, refer to Figure 10 The flowchart and operating steps of the component holding device 10 are explained. First, multiple components P are photographed by camera 40 to determine a state that is difficult to hold by hand 30. Preferably, a 3D camera is used as camera 40 to photograph components P in a loose state. The calculation unit 54 calculates the surface roughness based on the image captured by camera 40 and determines whether a pile of components P has formed. If no pile of components P has formed, it is determined to be a state that is difficult to hold (step S220). Next, the pair of holding parts 31 of hand 30 are opened. The width of the hand at that time is set to the maximum width within the range where the pair of holding parts 31 do not interfere with tray 60 (step S221). Next, the magnetic force adjustment unit 52 determines the magnetic force to be strong (step S222), thus connecting the magnetic force (step S223). As a result, multiple components P are attracted to the pair of holding parts 31 by magnetic force. In this state, the pair of holding parts 31 are closed, thereby gathering multiple components P together in one place (step S224). Next, the magnetic force is disconnected by the magnetic force adjustment unit 52 to form the component P stack (step S225).

[0116] Next, the hand 30 is moved upwards over the plurality of components P (step S226), and the camera 40 captures an image of the plurality of components P. The calculation unit 54 calculates the surface roughness based on the image captured by the camera 40 and determines whether a pile of components P has been formed (step S227). Next, the pair of gripping parts 31 of the hand 30 are opened to a width sufficient to hold the components P, and the hand 30 is moved towards the vicinity of the pile of components P. If components P are positioned between the pair of gripping parts 31, the components P are held by closing the pair of gripping parts 31 (step S228). Next, the components P are picked up by moving the hand 30 upwards (step S229).

[0117] [Effects of Implementation Method 2-2]

[0118] As described above, the hand part 30 of this disclosure is configured to attract the element P placed on the mounting part 61 to each of the gripping parts 31 by magnetizing the plurality of gripping parts 31 in an open state, and then gripping the element P by closing the plurality of gripping parts 31 and bringing the element P together in one place.

[0119] When, for example, the component P is arranged in a spread-out state on the mounting portion 61 of the tray 60, the success rate of gripping may be low. Even in this case, it is possible to form a state in which the component P is attracted to each gripping portion 31, and by closing the multiple gripping portions 31, the component P is concentrated in one place, thereby improving the success rate of gripping.

[0120] By performing the procedure as described in Embodiment 2-1 or Embodiment 2-2, it is possible to accurately grasp a wide variety of objects with different loading states.

[0121] [Details of Embodiment 3 of this disclosure]

[0122] Next, refer to Figure 11 as well as Figure 12 Embodiment 3 of this disclosure will be described. Embodiment 3 describes a method for holding multiple (two or more) elements P by magnetizing a hand 30 with a magnetic force greater than that used to hold one element P.

[0123] [Operational Description of the Component Holding Device]

[0124] Figure 11 (A) shows a case in which the gripping position of the element P based on the hand 30 is determined by taking a picture of the mounting part 61 of the tray 60 with the camera 40, and the hand 30 is moved to that gripping position. Figure 11 (B) shows a case in which multiple elements P are held by magnetizing the hand 30 with a strong magnetic force and closing a pair of gripping parts 31. Figure 11 (C) shows the situation where the hand 30 is moved above the tray 60. Figure 11 (D) shows a case where the unmanageable element P (the element P that is only attracted to the hand 30 by magnetic force) falls into the mounting part 61 of the tray 60 by breaking the magnetic force generated in the hand 30.

[0125] For example, the magnetic force (electricity) when holding a component P with a mass of 1g can be set to 50W, and the magnetic force (electricity) when holding a component P with a mass of 5g can be set to 250W. This magnetic force is 2.5 times that of the magnetic force in Embodiment 1, so multiple components P can be reliably held.

[0126] [Operating steps of the component holding device]

[0127] Next, refer to Figure 12 The flowchart is provided, and the operation steps of the component holding device 10 are explained. First, the arithmetic unit 54 uses the camera 40 to capture an image of the mounting section 61 of the tray 60. Based on the captured image, it determines which position the components P are most concentrated at, and determines the position where the components P are most concentrated as the holding position (step S30). Next, the arithmetic unit 54 queries the storage unit 55 for the mass of the held components P and refers to the component mass 57 (step S31). Similarly, it refers to the magnetic force and mass chart 58 (step S32). Based on the reference results of steps S31 and S32 and the number of held components P, the arithmetic unit 54 determines the magnetic force (step S33).

[0128] Next, the arithmetic unit 54 accesses the storage unit 55 and, referring to the hand width and component diagram 56, determines the hand width corresponding to the held component P (step S34). The hand width adjustment unit 53 moves the pair of holding parts 31 in such a way that the hand width determined in step S34 is achieved.

[0129] Next, the magnetic force adjustment unit 52 activates the magnetic force determined in step S33 (step S35). Then, the two gripping units 31 grip the component P (step S36), and the robot arm 21 picks up the component P (step S37). Next, the magnetic force is deactivated or reversed by the magnetic force adjustment unit 52 (step S38), causing the component P (which is fixed by magnetic force only on surfaces other than the opposing surface 34) to fall under its own weight. Next, a stronger magnetic force than in step S33 is activated by the magnetic force adjustment unit 52 (step S39), making it difficult to remove the component P. Then, the robot arm 21 transfers the component P to another mounting unit (step S40).

[0130] [Effects of Implementation Method 3]

[0131] As described above, the hand 30 of this disclosure holds multiple elements P with a magnetic force greater than that used to hold a single element P.

[0132] Multiple components P can be held without changing the hand part 30 and without destroying the components.

[0133] By performing the procedure as described in Embodiment 3, the transfer performance of the hand 30 can be improved.

[0134] [Other implementation methods]

[0135] (1) In the above embodiment, the camera 40 is shown to be mounted on a different part than the picking robot 20, but the camera 40 may also be mounted on the hand 30 of the picking robot 20.

[0136] (2) In the above embodiment, the hand 30 is shown to have a pair of gripping parts 31, but it can also be a hand with three or more gripping parts. The width of the hand can be adjusted as long as the spacing between the multiple gripping parts can be adjusted.

[0137] (3) In the above embodiment, element P is shown to be quadrilateral in side view, but it may also be a circular element in side view.

[0138] (4) In the above embodiment, coil 32 is used to magnetize the gripping part 31, but a permanent magnet can also be used to magnetize the gripping part. In this case, the magnetic force can be adjusted by moving the permanent magnet closer to or further away from the gripping part.

[0139] Explanation of reference numerals in the attached figures

[0140] 10: Component holding device

[0141] 20: Pickup robot 21: Robot arm 22: Support frame 23: Base 24: Link 25: Joint

[0142] 30: Hand part; 31: Holding part; 32: Coil; 33: Hand body part; 34: Opposite surface.

[0143] 40: Camera

[0144] 50: Control unit; 51: Grip position estimation unit; 52: Magnetic force adjustment unit; 53: Hand width adjustment unit; 54: Calculation unit; 55: Storage unit; 56: Hand width and component diagram; 57: Component mass; 58: Magnetic force and mass diagram.

[0145] 60: Tray; 61: Loading section

[0146] P: Component; SP: Small component; LP: Large component.

Claims

1. A component holding device, comprising: The hand has multiple gripping parts, through which the magnetic element is gripped; A picking robot that transfers the component held by the hand; and The control unit adjusts the magnetic force of the hand. After the control unit magnetizes the plurality of gripping parts and the picking robot picks up the component, it disconnects or reverses the magnetic force. Thus, in the event of an ungripable component, the control unit allows the component to be moved after it falls due to its own weight. The hand is configured to attract the element placed on the mounting part to each of the gripping parts by magnetizing the plurality of gripping parts in an open state, and then hold the element by closing the plurality of gripping parts to bring the element together in one place.

2. The component holding device according to claim 1, wherein, The control unit establishes a correlation between the magnetic force and the number of the held components by obtaining the number of the held components.

3. The component holding device according to claim 1 or 2, wherein, The hand has a plurality of gripping portions that are magnetic bodies and a coil that magnetizes the gripping portions.

4. The component holding device according to claim 3, wherein, The control unit is configured to use a strong magnetic force to magnetize the gripping part for components with large mass, and a weak magnetic force to magnetize the gripping part for components with small mass.

5. The component holding device according to claim 1 or 2, wherein, The hand holds multiple elements with a magnetic force greater than that used to hold a single element.

6. A component holding device, comprising: The hand has multiple gripping parts, through which the magnetic element is gripped; A picking robot that transfers the component held by the hand; and The control unit adjusts the magnetic force of the hand. After the control unit magnetizes the plurality of gripping parts and the picking robot picks up the component, it disconnects or reverses the magnetic force. Thus, in the event of an ungripable component, the control unit allows the component to be moved after it falls due to its own weight. The control unit adjusts the hand width, which is the spacing between the multiple gripping parts. The control unit establishes a correlation between the magnetic force, the hand width, and the number of elements being held by obtaining the number of elements being held.

7. A component holding device, comprising: The hand has multiple gripping parts, through which the magnetic element is gripped; A picking robot transfers the component held by the hand; as well as The control unit adjusts the magnetic force of the hand. After the control unit magnetizes the plurality of gripping parts and the picking robot picks up the component, it disconnects or reverses the magnetic force. Thus, in the event of an ungripable component, the control unit allows the component to be moved after it falls due to its own weight. The control unit includes: a magnetic force adjustment unit for adjusting the magnetic force of the hand; a hand width adjustment unit for adjusting the hand width, wherein the hand width is the spacing between the plurality of gripping parts; and a calculation unit for establishing an association between the magnetic force, the hand width, and the number of the components. And a storage unit that stores the associated magnetic force, hand width, and number of information.

8. The component holding device according to claim 7, wherein, The width of the hand is the distance between a pair of opposing gripping parts.

9. A component holding device, comprising: The hand has multiple gripping parts, through which the magnetic element is gripped; A picking robot that transfers the component held by the hand; and The control unit adjusts the magnetic force of the hand. After the control unit magnetizes the plurality of gripping parts in an open state and attracts the plurality of elements to the plurality of gripping parts respectively, it gathers the plurality of elements together by closing the plurality of gripping parts and forms a pile of elements by breaking the magnetic force.

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