Patent ID: 12208511

DETAILED DESCRIPTION

As workpieces to be worked, some workpieces, such as tablets, may be placed basically in any direction. However, other workpieces may be formed into, for example, plate shape, and directions of the workpieces when attached to objects may be predetermined. Further, such workpieces may be relatively small.

When multiple plate-shaped workpieces are supplied to a tray in a so-called batch manner, because of their thin thickness, it is considered that the workpieces are basically in a flat state with the thickness direction generally along a vertical direction.

In this case, it is conceivable that the workpieces are respectively assembled to the objects by suctioning and picking up the workpieces in the flat state, for example. However, depending on a size of a suction pad and a magnitude of a suction force, it may be difficult to assemble the suctioned workpiece to the object as it is.

Further, for example, when it is desired to assemble the workpiece in a predetermined direction, it is conceivable that the workpiece in the flat state is picked up from the tray, temporarily placed, and then re-gripped in the predetermined direction. However, in that case, it is necessary to take a long time to work, to provide multiple hands, to provide a temporary storage place, and the like.

According to an aspect of the present disclosure, a gripping apparatus includes a tray, a detector, a robot, and a controller. The tray is capable of being vibrated and has a placement surface on which multiple workpieces of plate shape are to be placed. The placement surface is provided with multiple recesses. The recesses are configured to cause the workpieces placed on the tray to be in a standing state with respect to the placement surface. The detector is configured to detect arrangement of the workpieces placed on the tray. The robot is attached with a hand configured to grip one of the workpieces. The controller is configured to control the robot and vibration of the tray.

The controller is further configured to move and insert the workpieces into the recesses by vibrating the tray, specify the workpieces in the standing state with the detector, and instruct the robot to grip one of the workpieces that are specified with the hand in a predetermined direction.

According to the above configuration, the gripping apparatus can vibrate the tray to align the workpieces, which are considered to be basically placed flat because of their thin thickness, in the standing state on the placement surface, and can grip one of the workpieces in the standing state in the predetermined direction.

Therefore, the gripping apparatus can grip the workpiece with one hand in the predetermined direction. Further, since the multiple recesses are provided, the work efficiency can be improved.

The following describes an embodiment with reference to the drawings. As shown inFIG.1, a gripping apparatus1of the present embodiment includes a feeder2, a camera3as a detector, a robot4, and a controller5. The gripping apparatus1performs a work of assembling a work piece supplied from the feeder2to, for example, an object8conveyed by a line7.

The feeder2includes a tray9and a vibration mechanism10that vibrates the tray9. The vibration mechanism10is controlled by the controller5. Multiple workpieces6can be placed on the tray9at a time, and the workpieces6can be supplied to the tray9, for example manually or automatically supplied from a supply device (not shown). InFIG.1, the workpieces6are hatched for the sake of explanation.

The camera3has an image capturing element such as a charge-coupled device (CCD) sensor or a complementary metal oxide semiconductor (CMOS) sensor, and captures an image of the workpieces6placed on the tray9and transmits the image to the controller5. The camera3is installed at a position above the tray9so that the image of the workpieces6placed on the tray9can be captured. By fixing the position of the camera3in this way, the workpieces6can be recognized while the robot4is assembling one of the workpieces6, and a cycle time can be shortened. However, the camera3may also be installed on the robot4so that the position of the camera3changes according to the change in the posture of the robot4.

The detector is not limited to the camera3, and a sensor, such as a laser sensor (not shown), capable of detecting the height difference and recognizing the shape of the workpiece6can be adopted if the sensor can recognize that the workpiece6is supplied in a predetermined direction. For example, a laser range finder can be used as the detector to detect whether or not the workpiece6is in a standing state. In that case, it is possible to determine whether the workpiece6is in the standing state by irradiating each recess13with a laser light and measuring a time until a reflected light is returned. In the present embodiment, a laser light is irradiated to multiple portions near an upper end of the workpiece6, and if the reflected light is not detected at the position corresponding to a notch and the reflected light is detected on the side without the notch, the direction of the workpiece6can be determined.

In the present embodiment, the robot4is assumed to be a so-called 4-axis robot of a horizontal articulated type. The robot4has a base4ainstalled on an installation surface, a first arm4bthat is rotatable around the base4a, a second arm4cthat is rotatable relative to the first arm4b, and a shaft4dthat is provided at a tip of the second arm4cand is vertically movable and rotatable relative to the second arm4c. At a tip, that is, a lower end side of the shaft4d, a hand11shown inFIG.2is attached. The hand11can also be attached to the shaft4dvia a flange or the like. Further, as the robot4, a so-called 6-axis robot or 7-axis robot of a vertical articulated type can also be adopted.

The hand11includes an attached portion11aand two gripping portions11b. The attached portion11ais attached to the shaft4d. The gripping portions11bare movable in a horizontal direction shown inFIG.2and grip the workpiece6in a predetermined direction. In the present embodiment, the gripping portions11bgrip the workpiece6from a thickness direction of the workpiece6. Then, as will be described later, the robot4assembles the workpiece6picked up from the tray9as it is, that is, by inserting it into, for example, a slit8aof the object8without re-gripping the workpiece6.

At this time, since the hand11grips the workpiece6from a side opposite to a side inserted into the slit8a, the hand11can assemble the workpiece6to the slit8awithout interfering with the object8. Further, since the hand11is generally attached to the shaft4dso as to be coaxially rotatable, the workpiece6can be rotated horizontally. If the robot4is a vertical articulated robot, the workpiece6can be oriented in any direction.

The operation of the robot4provided with the hand11is controlled by the controller5. As shown inFIG.3, the controller5includes a control unit5acomposed of a microcomputer having a CPU, a ROM, a RAM, and the like (not shown), a storage5bcomposed of a semiconductor memory, and the like. Although not shown, the controller5also includes an input-output circuit for transmitting and receiving data to or from an external device.

The controller5controls the robot4and, in the present embodiment, the camera3and the vibration mechanism10by executing a computer program stored in the storage5b. Specifically, the control unit5ais provided with a command value generation unit (CMD GEN)5c, a specifying unit (SPC)5d, a vibration control unit (VIB CTRL)5e, and the like. In the present embodiment, each of these units is realized by software by executing a computer program by the control unit5a.

The command value generation unit5cgenerates and outputs a drive command to a motor provided in the robot4. As a result, the motor (not shown) provided at a joint portion of the robot4is driven, and the robot4is controlled to arbitrary posture.

The specifying unit5dperforms an image processing to the image obtained by capturing the workpiece6placed on the tray9. Accordingly, the specifying unit5dspecifies the workpiece6that is in a state capable of being gripped by the hand11, more specifically, the workpiece6that is in the state capable of being gripped by the hand11and in the correct direction for being assembled to the object8.

The vibration control unit5egenerates and outputs a command value for the vibration mechanism10, which will be described in detail later. Then, the vibration mechanism10vibrates the tray9in two or three dimensions based on the output command value.

The workpiece6to be worked by the gripping apparatus1may have a plate shape, and may be relatively small. As shown inFIG.4AtoFIG.4C, the workpiece6has a rectangular plate shape, for example. In the front view shown inFIG.4B, the workpiece6has a length W in the left-right direction in which an outer dimension is maximum, and a length H in the up-down direction. Further, in the plan view shown inFIG.4A, the workpiece6has a length T. Hereinafter, W is also referred to as a width of the workpiece6, H is also referred to as a height of the workpiece6, and T is also referred to as a thickness of the workpiece6.

In the present embodiment, the term “plate shape” means that the thickness the workpiece6is smaller than the width and height of the workpiece6. To put it simply, it is assumed that the workpiece6is placed flat with its front surface6aor rear surface6bfacing in the vertical direction when the workpiece6is supplied to the tray9in a batch manner or when a slight vibration is applied to the workpiece6.

Further, the term “small” means that, for example, the maximum outer dimension, in the present embodiment, the width (W) is about several centimeters, or the height (H) shorter than the width is about several centimeters. However, the workpiece6is not limited to a rectangular plate shape, and may be a plate shape including a curved line, a triangular plate shape, or a polygonal plate shape of 5 or more sides. Workpieces having such shapes are collectively referred to workpieces of plate shape in the present embodiment.

Further, in the present embodiment, it is assumed that the direction of the workpiece6when assembled to the object8is predetermined, and the direction of the workpiece6is determined by an identifier12provided in the workpiece6as described later. For example, in the case of the workpiece6shown inFIG.4AtoFIG.4C, a label12aattached to the workpiece6and a notch12bprovided on the upper side of the workpiece6are assumed as the identifier12. Then, it is assumed that the direction in which the label12aand the notch12bare upward is the correct direction when the workpiece6is gripped or assembled to the object8.

However, in addition to these examples, the identifier12can also be any identifier such as characters, symbols, or wiring patterns printed on the workpiece6from which the correct direction when assembling the workpiece6can be visually determined. In that case, one or more identifiers12can be provided on the workpiece6. Further, when multiple identifiers12are provided, the correct direction can be determined based on the identification result of one identifier12, and can also be determined based on the identification result of two or more identifiers12such as the physical shape of the workpiece6and printing.

Hereinafter, in the present embodiment, the correct direction when gripping the workpiece6or assembling the workpiece6to the object8, that is, a state where the workpiece6stands up with respect to a placement surface9aof the tray9and the label12ais positioned on the upper side is also referred to as a standing state.

As shown inFIG.1andFIG.4AtoFIG.4C, the workpiece6is supplied to the gripping apparatus1in a state of being placed on the tray9mounted on the vibration mechanism10. As shown inFIG.5AandFIG.5B, the tray9is mounted on the vibration mechanism10and is capable of being vibrated as a whole. When the left-right direction shown in the plan view ofFIG.5Ais the X direction, the up-down direction shown in the plan view ofFIG.5Ais the Y direction, and the up-down direction shown in the front view ofFIG.5Bis the Z direction, the tray9can vibrate in any one direction, any two directions, or all three directions of the X direction, the Y direction, and the Z direction. Hereinafter, the vibration in the X direction and the Y direction is also referred to as a vibration in the horizontal direction.

When the tray9is vibrated in, for example, the X direction or the Y direction while the workpieces6are placed on the tray9, the workpieces6placed on the placement surface9amove in the tray9accompanied with the vibration. Further, when the tray9is vibrated in the Z direction, the workpieces6are momentarily lifted from the placement surface9a. Therefore, even when multiple workpieces6are collectively supplied to the tray9, the position of each workpiece6can be changed by vibrating the tray9.

As shown inFIG.6, the tray9has the placement surface9aon which the workpieces6are to be placed and a wall portion9bprovided around the placement surface9a, and is formed in a shape of a container with an open upper part when the tray9is mounted on the vibration mechanism10. The placement surface9ais provided with multiple recesses13for aligning the workpieces6in the standing state. In other words, the recesses13are provided to align the workpieces6in the standing state in which the workpieces6can be gripped by the hand11. However, the shape of the tray9and the number of recesses13or the arrangement of the recesses13shown inFIG.6are examples, and are not limited thereto.

Specifically, as shown inFIG.7A,FIG.7B,FIG.8AandFIG.8B, each recess13includes a groove14formed by being recessed from the placement surface9aand an inclined surface15inclined toward the groove14from the placement surface9a. In the plan view, the groove14is formed into a rectangular shape having a lateral side corresponding to the thickness direction of the workpiece6and a longitudinal side corresponding to the width direction of the workpiece6, and has such a size that one workpiece6in the standing state can be inserted.

On the other hand, in the case of the present embodiment, the inclined surface15includes a lateral inclined surface15aformed along the lateral side of the groove14and a longitudinal inclined surface15bformed along the longitudinal side of the groove14. However, the inclined surface15may also have a configuration in which either the lateral inclined surface15aor the longitudinal inclined surface15bis provided.

More specifically, as shown inFIG.7AandFIG.7B, the groove14has a width (W1) slightly larger than the width (W) of the workpiece6, a thickness (T1) slightly larger than the thickness (T) of the workpiece6and smaller than 2×T, and a height (H1) from the placement surface9ato the lower end, which is shorter than the height (H) of the workpiece6. Therefore, as shown in the inserted state inFIG.7B, when the lower end side of the workpiece6is inserted into the groove14, the upper end side of the workpiece6protrudes upward from the placement surface9aby H−H1. The portion protruding upward from the placement surface9abecomes a portion gripped by the hand11.

As shown inFIG.7A, the lateral inclined surface15ais inclined at an inclination angle (α) of approximately 45 degrees with respect to the placement surface9aand is connected to the groove14. Therefore, the entire width (W2) of the recess13including the lateral inclined surface15ais larger than the width (W) of the workpiece6. Therefore, when the workpiece6moves in the left-right direction shown inFIG.7AandFIG.7B, the entire workpiece6is put into the recess13. However, the inclination angle (α) is an example, and an angle other than 45 degrees can be set.

As shown inFIG.8A, the longitudinal inclined surface15bhas a first inclined surface15b1and a second inclined surface15b1. The first inclined surface15b1is inclined at an inclination angle (β) of about 45 degrees with respect to the placement surface9a. The second inclined surface15b1connects a lower end side of the first inclined surface15b1and the groove14. The second inclined surface15b1is inclined at an inclination angle (γ) of about 60 degrees with respect to the placement surface9a. However, the inclination angle (β) and the inclination angle (γ) are examples, and other angles can be set. Further, the longitudinal inclined surface15bcan be formed in a shape such that β>γ, or the second inclined surface15b2may be omitted.

Next, the effects of the configuration described above will be explained. As described above, when multiple workpieces6of plate shape are supplied to the tray9in a batch manner, it is considered that the workpieces6are basically placed flat because the thickness of the workpieces6is thin. In this case, when assembling the workpiece6to the object8, it is conceivable to suction and pick up the workpiece6in the flat state, for example. However, depending on a size of a suction pad and a magnitude of a suction force, it may be difficult to assemble the suctioned workpiece6to the object8as it is.

Further, when the direction when assembling the workpiece6to the object8is predetermined as in the present embodiment, there may be a case where the workpiece6in the flat state is once picked up from the tray9, temporarily placed in the predetermined direction, and re-gripped in a correct direction. In that case, it is necessary to take a long time to work, provide multiple hands11, and provide a temporary storage place.

Therefore, the gripping apparatus1is configured to grip the workpiece6of plate shape with one hand11in the predetermined direction. Specifically, the gripping apparatus1executes a gripping process shown inFIG.9. This process is executed by the controller5, but for the sake of simplification of the description, the gripping apparatus1will be mainly described below. Further, it is assumed that multiple workpieces6are supplied to the tray9in the batch manner and each workpiece6is placed in a substantially flat state before the gripping process is executed.

First, in S1, the gripping apparatus1executes a vibration process for vibrating the tray9to which the workpieces6are supplied. At this time, the gripping apparatus1vibrates the tray9by outputting a vibration direction and a vibration time for vibrating the tray9to the vibration mechanism10as command values. The following describes a moving mode of the workpiece6while the vibration process is being executed, that is, a mode in which the workpiece6in the flat state is aligned in the standing state with reference toFIG.10AtoFIG.10Eshowing a cross section in the longitudinal direction of the recess13andFIG.11AtoFIG.11Eshowing a cross section in the lateral direction of the recess13.

In reality, changes in the movement mode shown inFIG.10AtoFIG.10EandFIG.11AtoFIG.11Emay occur concurrently, but here, for the sake of simplification of the description, the movement mode in the longitudinal direction shown inFIG.10AtoFIG.10Eand the movement mode in lateral direction shown inFIG.11AtoFIG.11Eare described individually. Further, this step corresponds to a step of causing the workpiece6to be in the standing state.

In the longitudinal direction, as shown inFIG.10A, the vibration process is executed, for example, in a state where the workpiece6is placed horizontally on the placement surface9aon the right side of the recess13, and the tray9is vibrated in the horizontal direction such as the Y direction shown by the arrow Y. At this time, the workpiece6moves toward the recess13accompanied with the vibration of the tray9as shown inFIG.10B, and is guided toward the groove14by the inclined surface15.

Since the width (W1) of the recess13is larger than the width (W) of the workpiece6, the position of the workpiece6that has entered the range of the width of the recess13converges toward the groove14located at the lower end of the inclined surface15as shown inFIG.10C. As a result, the lower end of the workpiece6is inserted into the groove14, as shown inFIG.10D.

In the lateral direction, as shown inFIG.11A, the vibration process is executed, for example, in a state where the workpiece6is placed horizontally on the placement surface9aon the right side of the recess13, and the tray9is vibrated in the horizontal direction such as the X direction shown by the arrow X. At this time, the workpiece6moves toward the recess13accompanied with the vibration of the tray9as shown inFIG.11B, and is guided toward the groove14by the inclined surface15.

Since the thickness (T1) of the recess13is larger than the thickness (T) of the workpiece6, the position of the workpiece6that has entered the range of the thickness of the recess13converges toward the groove14located at the lower end of the inclined surface15as shown inFIG.11C. As a result, the lower end of the workpiece6is inserted into the groove14, as shown inFIG.11D.

By executing the vibration process of vibrating the tray9in this way, the lower end of the workpiece6is inserted into the groove14, and the workpiece6is in the standing state with its thickness direction along the placement surface9a. It is assumed that multiple workpieces6are guided toward the same recess13, but since the groove14is formed to be as large as the thickness of one workpiece6, one workpiece6is arranged in one recess13.

However, the vibration process does not necessarily guarantee that all the workpieces6will be in the standing state, and is performed with the expectation that a certain number of workpieces6will be in the standing state. In addition, performing some process with expectation of a certain result in this way can also be expected to shorten the cycle time as a result, so it is a general idea in the technical field of aligning the direction of parts by vibration.

Therefore, in the present embodiment, by conducting a preliminary experiment, the vibration process is executed by setting the vibration direction and the vibration time in which a certain number of workpieces6are expected to be in the standing state. Therefore, when the vibration process is completed, it can be expected that the certain number of workpieces6are in the standing state.

However, it is also possible to dynamically change the vibration time and the vibration time. For example, the vibration process may be executed while capturing an image of the inside of the tray9with the camera3, and the vibration process may be completed when the number of the workpieces6in the standing state reaches a certain number, or the vibration direction may be determined according to the direction of the workpiece6.

When the vibration process is completed, the gripping apparatus1captures an image of the inside of the tray9with the camera3in S2. Subsequently, in S3, the gripping apparatus1determines whether there is a workpiece6in the standing state by performing image processing on the captured image.

At this time, the gripping apparatus1determines whether there is a workpiece6in the standing state by recognizing the workpieces6present in the image and determining the directions of the workpieces6by using the identifier12provided on each of the workpiece6. Further, in the case of the present embodiment, using the image captured in S2, it is determined in S3whether multiple workpieces6present in the image are in the standing state.

In a case where the workpiece6has a plate shape, there is a possibility that workpiece6is inserted in a state where the notch12bis located at the lower end side of the groove14, that is, the direction is upside down from the predetermined direction, for example, as shown inFIG.10EandFIG.11E. Therefore, in S3, the gripping apparatus1visually determines whether there is a workpiece6in the standing state by capturing the image of the inside of the tray9with the camera3. This step corresponds to a step of determining whether the workpiece6is in the standing state.

As a result, the accuracy when determining the direction of the workpiece6can be improved, and the image of the entire inside of the tray9can be captured, so that the number of the workpieces6in the standing state and the number of workpieces6remaining in the tray9can be easily grasped.

Then, when there is a workpiece6in the standing state (YES in S3), the gripping apparatus1identifies the position of the workpiece6in the standing state in S4, and the hand11is moved and the workpiece6is gripped in S6. These steps correspond to steps of gripping the workpiece6.

After that, the gripping apparatus1assembles the workpiece6to the object8in S7. That is, after the workpiece6is picked up from the tray9, the gripping apparatus1assembles the workpiece6to the object8with one hand11without re-gripping the workpiece6. This step corresponds to a step of assembling the workpiece6to the object8.

When the assembly is completed, the gripping apparatus1determines in S8whether the work has been completed. When the gripping apparatus1determines that the work has been completed (YES in S8), for example, when a required number of workpieces6are assembled, the process ends.

On the other hand, when the gripping apparatus1determines that the work has not been completed (NO in S8), determines in S9whether there is another workpiece6in the standing state in the tray9. Then, when there is another workpiece6in the standing state (YES in S9), the gripping apparatus1proceeds to S4to repeat a process for specifying the position of the workpiece6, moving the hand11in S5, gripping the workpiece6in S6, and assembling the workpiece6to the object8in S7.

In the present embodiment, since it is determined in S3whether the workpiece6is in the standing state for multiple workpieces6, it is determined in S9whether there is another workpiece6without capturing another image. However, if the determination result in S8is NO, the process proceeds to S2to capture another image of the inside of the tray9, and it may be determined whether there is another workpiece6in the standing state.

For example, when all the workpieces6in the standing state are assembled and the determination result in S9becomes NO, or for example, when the workpieces6do not become the standing state even if the vibration process is executed and the determination result in S3becomes NO, the gripping apparatus1determines in S10whether the number of remaining workpieces6that remain in the tray9is equal to or greater than a predetermined reference number. That is, in S10, the gripping apparatus1determines the number of remaining workpieces6remaining in the tray9even though not in the standing state.

This is because, when the number of the remaining workpieces6is too small, it is considered that the workpieces6in the standing state can be more efficiently secured by adding the workpieces6and executing the vibration process, while when the number of the remaining workpieces6is large, it is considered the workpieces6in the standing state can be secured to some extent even if the vibration process is executed without adding the workpieces6. Therefore, the reference number can be appropriately set based on, for example, a preliminary experiment or an empirical rule, or can be set by calculating the probability of being in standing state from the number of recesses13and the number of remaining workpieces6.

In a case where the number of the workpieces6in the standing state is determined and a determination that a certain number or more of the workpieces6are in the standing state is a condition for ending the vibration, if the number is slightly less than the certain number, the workpieces6in the standing state may come off from the groove14by continuously applying the vibration strongly. Therefore, the workpieces6may be vibrated with a slightly weaker vibration than the initial strength. Further, if it is determined that the number of workpieces6in the standing state is overwhelmingly insufficient, although the workpieces6currently in the standing state will no longer be in the standing state, a vibration stronger than the initial strength may be applied. That is, the gripping apparatus1may have a configuration in which the vibration amount is adjustable.

Then, when the number of the remaining workpieces6is equal to or greater than the reference value (YES in S10), the process proceeds to S1to execute the vibration process. On the other hand, when the number of the remaining workpieces6is less than the reference number (NO in S10), the process proceeds to S11to add the workpieces6to the tray9, and then the process proceeds to S1to execute the vibration process.

At this time, it is assumed that the workpiece6not in the standing state is placed flat on the arranging plane9a. However, for example, as shown inFIG.10E, the workpiece6may be inserted in the groove14in the opposite direction. Therefore, when the process proceeds to S1, as shown inFIG.10EandFIG.11E, the gripping apparatus1vibrates the tray9in the Z direction, so that the workpiece6is discharged from the groove14. That is, the inserted state of the workpiece6is reset once.

As a result, even if the workpiece6is inserted into the groove14in the opposite direction, the workpiece6can be discharged from the groove14, and then vibrated in the X direction or the Y direction so that the workpiece6is guided to the recess13and is inserted into the groove14. Even when the workpiece6is supplied or added to the tray9, the workpiece6may be accidentally inserted into the groove14in the opposite direction. Therefore, in S1, the gripping apparatus1may first vibrate the tray9in the Z direction so that the inserted state is reset, and then vibrate the tray9in the X direction or the Y direction.

As described above, when the gripping apparatus1grips the workpiece6of plate shape, the workpiece6is once aligned in the standing state and then gripped from the thickness direction, so that the workpiece6can be gripped in the predetermined direction suitable for assembly, and the workpiece6can be assembled to the object8without being re-gripped.

According to the embodiment described above, the following effects can be achieved. The gripping apparatus1includes the tray9, the feeder2, the camera3, the robot4, and the controller5. The tray9has the recesses13provided on the placement surface9aon which the multiple workpieces6are to be placed, and the recesses13cause the workpieces6to be in the stating state in which the workpieces6stand with respect to the placement surface9a. The feeder2includes the vibration mechanism10for vibrating the tray9. The camera3captures an image of the workpieces6placed on the tray9. The robot4is attached with the hand11for gripping the workpiece6. The controller5controls the robot4and the vibration mechanism10.

Then, the controller5executes a process of vibrating the tray6with the vibration mechanism10to move and insert the workpiece6into the recess13, a process of specifying the workpiece6in the standing state by capturing an image of the tray9with the camera3, and a process of controlling the robot4to grip the specified workpiece6from the thickness direction with the hand11.

According to such a configuration, the gripping apparatus1can vibrate the tray9to align the workpiece6of plate shape, which is considered to be basically placed flat because of its thin thickness, in the standing state on the placement surface9a, and can grip the workpiece6in the standing state from the thickness direction.

Therefore, the workpiece6of plate shape can be gripped with one hand11in the predetermined direction. Further, since the multiple recesses13are provided, the work efficiency can be improved.

Further, the controller5executes a process of assembling the gripped workpiece6to the object8without re-gripping the workpiece6. As a result, the gripping apparatus can assemble the workpiece6to the object8without re-gripping the workpiece6, and unlike the configuration in which the workpiece6is temporarily placed in the predetermined direction, the number of steps required for the work can be reduced, it is possible to suppress an increase in cycle time, it is not necessary to provide multiple hands11, and it is not necessary to provide a temporary storage place. Therefore, the work efficiency can be improved, and the required equipment and installation space can be reduced.

The recess13provided in the tray9includes the groove14formed in such a size that the workpiece6can be inserted in the standing state, and the inclined surface15inclined toward the groove14. Accordingly, when the tray9is vibrated in the X direction or the Y direction, the workpiece6is guided to the groove14along the inclined surface15, so that the workpiece6is inserted into the groove14and the workpiece6is efficiently brought into the standing state.

Further, the controller5changes the amount of vibration when vibrating the tray9based on the number of workpieces6in the standing state. Accordingly, for example, when the number of workpieces6is a little less than a predetermined number, that is, the above-described reference value, although the workpieces6in the standing state may come off from the recess13if the workpieces6are continuously vibrated strongly, it is possible to encourage the workpieces6that are not in the standing state to be in the standing state while the workpieces6that are in the standing state remain the standing state by slightly weakening the amount of vibration.

Alternatively, for example, when it is determined that the number of the workpieces6in the standing state is overwhelmingly insufficient for the reference value, although a small number of the workpieces6in the standing state may no longer be in the standing state, by strengthening the amount of vibration, it is possible to encourage more workpieces6to be in the standing state.

When the workpiece6is arranged in the recess13in the opposite direction, the controller5resets the arrangement of the workpiece6by vibrating the tray9. Accordingly, the workpiece6arranged in a direction different from the predetermined direction can be re-arranged in a state capable of being gripped, that is, in the predetermined direction.

Further, in the present embodiment, the camera3is used as the detector. Accordingly, the accuracy when determining the direction of the workpieces6can be improved, and the image of the entire inside of the tray9can be captured, so that the number of the workpieces6in the standing state and the number of workpieces6remaining in the tray9can be easily grasped, and it becomes easy to control the above-described change in the amount of vibration and reset of arrangement.

Further, using such a gripping apparatus1, effects similar to those of the gripping apparatus1, such as capable of gripping the workpiece6of plate shape with one hand11, can be obtained by a method including a step of moving and inserting the workpieces6into the recesses13by vibrating the tray9, a step of specifying the workpieces6in the standing state by capturing an image of the tray9with the camera3, a step of controlling the robot4to grip the specified workpiece6from the thickness direction with the hand11.

The above-described embodiment illustrates the configuration in which the longitudinal inclined surface15band the lateral inclined surface15aare provided. In another configuration example, as shown inFIG.12A, only the longitudinal inclined surface15bmay be provided while the lateral inclined surface15ais not provided. Even with such a configuration, since the workpiece6can be guided to the groove14, it is possible to obtain the effects, such as capable of gripping the workpiece6of plate shape with one hand11in the predetermined direction.

In another configuration example, as shown inFIG.12B, the lateral inclined surface15amay be formed into a curved surface. Further, the longitudinal inclined surface15bmay also be formed into a curved surface. Even with such a configuration, since the workpiece6can be guided to the groove14, it is possible to obtain the effects, such as capable of gripping the workpiece6of plate shape with one hand11in the predetermined direction.

The above-described embodiment illustrates the configuration in which the first inclined surface15b1and the second inclined surface15b2are provided on the longitudinal inclined surface15b. In another configuration example, as shown inFIG.13A, the longitudinal inclined surface15bmay be provided with one inclined surface. The groove14may also be tapered toward the lower end. Even with such a configuration, since the workpiece6can be guided to the groove14, it is possible to obtain the effects, such as capable of gripping the workpiece6of plate shape with one hand11in the predetermined direction.

In another configuration example, as shown inFIG.13B, the groove14may include a first portion14aand a second portion14bnarrower than the first portion14a. With such a configuration, when the workpiece6is guided to the groove14, the insertion into the groove14can be promoted. Of course, it is possible to obtain the effects, such as capable of gripping the workpiece6of plate shape with one hand11in the predetermined direction.

Further, these configuration examples can be combined with the configuration of the above-described embodiment or other configuration examples. For example, as shown inFIG.13C, the longitudinal inclined surface15bmay be formed into a curved surface, the groove14may include the first portion14a, the second portion14bnarrower than the first portion14a, and a taper portion between the first portion14aand the second portion14b. Even with such a configuration, when guiding the workpiece6to the groove14, insertion into the groove14can be promoted, and it is possible to obtain the effects, such as capable of gripping the workpiece6of plate shape with one hand in the predetermined direction.

The above description is merely examples and does not limit the technical scope of the present disclosure. The present disclosure can be modified and combined in various ways without departing from the gist thereof, and they are also included in the equivalent range.