Industrial robot and adsorption device

Abstract

To protect a packaging material being an adsorption object while stably exhibiting an adsorption function.SOLUTION: An industrial robot is equipped with an adsorption pad 42 mounted at the fingertip of an arm, and a pipe section connecting the adsorption pad 42 to a suction pump. The adsorption pad 42 includes a head 51 that contacts a packaging material PF when holding a workpiece W composed of the packaging material PF and a storage article PD stored in the packaging material PF. Inside the head 51, a mesh member 71 that has a planar shape intersecting with an intake hole 51a formed in the head 51 is arranged. The mesh member 71 is elastically deformable, and during adsorption of the packaging material PF, the mesh member 71 pressed by the packaging material PF bends and is deformed in the suction direction by the pump together with the packaging material PF.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an industrial robot and a suction device applied to the industrial robot.

Background Art

[0002] Some industrial robots having an articulated arm are capable of mounting a hand for holding a workpiece at the tip of the arm. This type of hand includes those configured to clamp a workpiece by a plurality of finger portions, and those configured to adsorb a workpiece by a suction pad (suction head) connected to a pump via a pipe (see, for example, Patent Document 1). For example, Patent Document 2 proposes a robot that adsorbs and transfers a workpiece in which food is contained in a bag (packaging material) by a suction pad.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Regarding the adsorption type hand described above, many are configured to generate an adsorption force for adsorbing a workpiece by sucking air from the adsorption pad using a pump. To adsorb and hold a workpiece, an appropriate adsorption force is required, and the adsorption function can be stably exhibited by setting the adsorption force to be relatively large. Here, in the case of a workpiece whose article is packaged with a relatively thin packaging material such as polyethylene, vinyl chloride, cellophane, or paper, wrinkles may occur in the packaging material by generating an adsorption force of a size that can stably adsorb the workpiece. And when wrinkles remain in the packaging material, even if there are no quality problems with the packaged article itself, it may become a target for disposal, and it is assumed that the yield of the product (workpiece) will decrease. In particular, in the food field, such an event can be a factor in food loss. Thus, in a configuration in which the packaging material is adsorbed to hold the workpiece, there is still room for improvement in the configuration in terms of protecting the packaging material to be adsorbed while stably exhibiting the adsorption function.

[0005] The present invention has been made in view of the above-exemplified problems and the like, and its main object is to protect the packaging material to be adsorbed while stably exhibiting the adsorption function.

Means for Solving the Problems

[0006] Hereinafter, the means for solving the above problems will be described.

[0007] The first means. An adsorption device that is applied to an industrial robot and adsorbs a workpiece obtained by packaging an article using a packaging material, An adsorption head that contacts the packaging material of the workpiece, A suction pump, A pipe section connecting the adsorption head and the pump and comprising, The adsorption head is provided with a net-like member that forms a planar shape intersecting the flow path formed in the adsorption head and can be bent and deformed in the suction direction by the pump.

[0008] When the packaging material is the object to be adsorbed during the adsorption of the workpiece, it is preferable to increase the adsorption force to a certain extent in order to stably exert the adsorption function. However, if the adsorption force increases, the load on the packaging material also increases, and wrinkles may occur in the packaging material due to deformation beyond the elastic range. This is a factor that reduces the yield of the workpiece (product). In this regard, in the configuration shown in this means, the packaging material drawn into the flow path during adsorption hits the mesh member during the drawing process. The mesh member pushed by the packaging material bends and deforms toward the back side of the flow path together with the packaging material, and the packaging material is prevented from deforming greatly instantaneously. Avoiding such rapid deformation of the packaging material is preferable for protecting the packaging material. In addition, by using a mesh member that bends and deforms toward the back side of the flow path, it is possible to suppress a large load from being applied to a part of the packaging material. Thereby, the protection function of the packaging material can be strengthened. For the above reasons, according to the configuration shown in this means, even if the adsorption force is increased to a certain extent to stabilize the adsorption function, it can be suppressed that this causes wrinkles in the packaging material, and the stabilization of the adsorption function and the protection of the packaging material can be suitably achieved simultaneously.

[0009] Second means. An industrial robot having an arm formed with a plurality of joint portions, an adsorption head that is attached to the tip of the arm and contacts the packaging material when holding a workpiece obtained by packaging an article using the packaging material, a pipe portion that is attached to the arm and connects the adsorption head and a suction pump, and is provided with an adsorption device having the adsorption head is provided with a planar mesh member that intersects the flow path formed in the adsorption head and is capable of bending and deforming, the mesh member is configured to bend and deform so as to protrude in the suction direction together with the packaging material by being pushed in the suction direction by the sucked packaging material.

[0010] According to the configuration shown in this means, even if the adsorption force is increased to a certain extent to stabilize the adsorption function, it can be suppressed that this causes wrinkles in the packaging material, and the stabilization of the adsorption function and the protection of the packaging material can be suitably achieved simultaneously.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0012] Hereinafter, an embodiment embodied in a robot system used in a boxing process or the like in a food manufacturing factory will be described with reference to the drawings.

[0013] As shown in FIG. 1, the robot system 10 includes a robot 15 which is a vertical articulated industrial robot. The main body of the robot 15 (robot main body 21) includes a base portion 22 fixed to a pedestal or the like, a shoulder portion 23 supported by the base portion 22, a lower arm portion 24 supported by the shoulder portion 23, a first upper arm portion 25 supported by the lower arm portion 24, a second upper arm portion 26 supported by the first upper arm portion 25, a wrist portion 27 supported by the second upper arm portion 26, and a flange portion 28 supported by the wrist portion 27.

[0014] A first joint portion that connects the base portion 22 and the shoulder portion 23 is formed on the base portion 22 and the shoulder portion 23, and the shoulder portion 23 is rotatable horizontally about the connecting axis (first axis AX1) of the first joint portion. A second joint portion that connects the shoulder portion 23 and the lower arm portion 24 is formed on the shoulder portion 23 and the lower arm portion 24, and the lower arm portion 24 is rotatable vertically about the connecting axis (second axis AX2) of the second joint portion. A third joint portion that connects the lower arm portion 24 and the first upper arm portion 25 is formed on the lower arm portion 24 and the first upper arm portion 25, and the first upper arm portion 25 is rotatable vertically about the connecting axis (third axis AX3) of the third joint portion. A fourth joint portion that connects the first upper arm portion 25 and the second upper arm portion 26 is formed on the first upper arm portion 25 and the second upper arm portion 26, and the second upper arm portion 26 is rotatable in the twisting direction about the connecting axis (fourth axis AX4) of the fourth joint portion. A fifth joint portion that connects the second upper arm portion 26 and the wrist portion 27 is formed on the second upper arm portion 26 and the wrist portion 27, and the wrist portion 27 is rotatable vertically about the connecting axis (fifth axis AX5) of the fifth joint portion. A sixth joint portion that connects the wrist portion 27 and the flange portion 28 is formed on the wrist portion 27 and the flange portion 28, and the flange portion 28 is rotatable in the twisting direction about the connecting axis (sixth axis AX6) of the sixth joint portion.

[0015] The shoulder portion 23, the lower arm portion 24, the first upper arm portion 25, the second upper arm portion 26, the wrist portion 27, and the flange portion 28 are arranged in a series to constitute the arm 31 in the robot body 21. The arm 31 is provided with a servo motor and a speed reducer for joint drive as an electric actuator for rotating each joint portion, a rotary encoder for detecting the rotation angle of each joint portion (axis), a non-excitation operating electromagnetic brake, and a motor control board (servo amplifier) for performing drive control of the servo motor, etc. A motor unit is provided for each joint portion.

[0016] A vacuum suction pad 42 as an end effector is attached to a flange portion 28 that constitutes the tip (hand) of the arm 31. The suction pad 42 is connected to a pump 44 via a piping portion 43 built into the arm 31, and air is sucked from the suction pad 42 when the pump 44 operates. For example, by operating the pump 44 to generate a negative pressure with the suction pad 42 pressed against the workpiece W, the workpiece W is adsorbed to the suction pad 42. The suction device 41 is constituted by the suction pad 42, the piping portion 43, and the pump 44. The robot 15 shown in this embodiment is provided alongside a conveyor C on which the workpiece W is conveyed, and performs a boxing operation (pick / place) on the workpiece W conveyed by the conveyor C.

[0017] Here, with reference to FIG. 2, a supplementary explanation will be given of the electrical configuration of the robot system 10. The robot system 10 includes a robot controller 16 as a general control device, and the motor control board 35 and the pump 44 described above are connected to the robot controller 16.

[0018] A servo motor 36 and a rotary encoder 37 are connected to the motor control board 35, and the motor control board 35 specifies an operation target position in response to an operation instruction for work received from the robot controller 16. Then, drive control of the servo motor 36 is performed based on the operation target position and the position data acquired from the rotary encoder 37, that is, the encoder value indicating the rotation angle (rotation position) of the servo motor 36.

[0019] Each motor unit of the robot 15 is provided with a force sensor 38 which is a torque detection sensor for detecting the torque generated at the joint portion. The force sensor 38 includes a plurality of strain gauges disposed in the speed reducer, and a detection unit connected to each strain gauge via a lead wire. The detection unit is provided with a bridge circuit unit which is an electric circuit suitable for detecting minute changes in resistance value, and an amplifier unit for amplifying each signal detected by the bridge circuit unit. The amplified signal is transmitted to a motor control board 35 mounted on the motor unit. The motor control board 35 can decelerate or stop (including protective stop) the robot 15 according to the signal (detected torque) from the force sensor 38, and the safety of the robot system 10 is improved.

[0020] Further, the robot controller 16 picks up / places the workpiece W by driving and controlling (ON / OFF) the pump 44. As shown in the schematic diagram of FIG. 3, the workpiece W includes a film-like packaging material PF and a contained object PD packaged (accommodated) by the packaging material PF. In the present embodiment, for example, soft packaging (specifically, single film packaging, multilayer film packaging, retort pouch packaging) made of a soft material with a thin thickness and likely to cause shape change such as polyethylene, vinyl chloride, cellophane or paper is assumed, and as the workpiece W, foods such as bread, snacks, cut vegetables sold in supermarkets and convenience stores are assumed. Note that the workpiece W is not limited to foods, and any object packaged by a packaging material may be used, such as daily necessities like pocket tissues or medical products like gauze.

[0021] Here, with reference to FIG. 3, a supplementary explanation will be given of the configuration related to the adsorption of the workpiece W. The adsorption pad 42 includes a head 51 that contacts the workpiece W when adsorbing the workpiece W, and a holder 61 that holds the head 51. The holder 61 is fixed to the arm 31 (specifically, the flange portion 28), and is integrated with the arm 31. The head 51 is an attachment that can be changed according to the type of the workpiece W.

[0022] The head 51 has a cylindrical base portion 52 that forms part of the intake hole 51a of the head 51, and together with the pipe portion 43 connected to the holder 61, forms a single flow path F. The base portion 52 is coaxial with the sixth axis AX6 (see FIG. 1) that engages with the flange portion 28, and at one end portion (tip portion) thereof, it forms an annular shape that expands in the radial direction of the sixth axis AX6, and a diameter-expanded portion 53 is provided that is formed such that the diameter gradually increases as it moves away from the base portion 52. The inner peripheral surface of the diameter-expanded portion 53 constitutes part of the adsorption surface 81 of the work W on the head 51. The diameter-expanded portion 53 (head 51) is formed of a soft synthetic resin (rubber) in order to suppress damage to the work W when it comes into contact with the work W, and has a buffering function of relaxing the impact when it hits the work W by flexing itself.

[0023] Here, in order to suppress the detachment of the adsorbed work W and stably exhibit the holding function of the work W, it is effective to increase the suction force by the pump 44, that is, the adsorption force of the work W. However, when the packaging material PF is the adsorption target, the following adverse effects may occur by increasing the adsorption force. Hereinafter, the adverse effects will be described with reference to the comparison target shown in FIG. 4.

[0024] The soft packaging material PF is more likely to deform during adsorption compared to hard planar members such as substrates and frame materials. In particular, the negative pressure becomes large at a portion where the inner diameter becomes small in the adsorption pad 42X (for example, near the boundary portion 54X between the base portion 52X and the diameter-expanded portion 53X), and when the adsorption force is increased, a part of the adsorbed packaging material PF may largely enter into the base portion 52.

[0025] When the deformation of the packaging material PF is within the elastic range, the adsorption is terminated and the workpiece W is lowered, so that the packaging material PF returns to its original state. On the other hand, as shown in Fig. 4(a), when the adsorption force becomes large and the packaging material PF largely enters beyond the boundary portion 54X, a load concentrates on a part of the packaging material PF, for example, in the vicinity of the boundary portion 54X, and the degree of deformation of the packaging material PF may exceed the elastic range. When such an event occurs, wrinkles are formed in the packaging material PF to be adsorbed as shown in Fig. 4(b). And when wrinkles remain in the packaging material PF, even if there is no quality problem in the contained product PD itself, this workpiece W may be subject to disposal. That is, the yield of the product is reduced. In particular, in the food field, the occurrence of such an event can be a factor in food loss.

[0026] In the configuration of adsorbing and holding the packaging material PF in this way, there is still room for improvement in the configuration in order to protect the packaging material PF to be adsorbed while stably exerting the adsorption function. In the present embodiment, one of the features is that a device is devised in consideration of such circumstances. Hereinafter, with reference to Figs. 5 and 6, the device will be described.

[0027] Inside the diameter-expanded portion 53 (opening portion), that is, in the portion forming the flow path F, a net-like member 71 having a planar shape intersecting the flow path F is disposed. The net-like member 71 is disposed at a position near the boundary portion 54 between the base portion 52 and the diameter-expanded portion 53 in the diameter-expanded portion 53, and covers the boundary portion 54 from the inlet side of the flow path F. The net-like member 71 has an annular frame portion 72, and an annular groove portion 56 into which the frame portion 72 is inserted is formed on the inner peripheral surface of the diameter-expanded portion 53. By fitting the frame portion 72 inserted into the groove portion 56 with the groove portion 56, the net-like member 71 is fixed so as not to fall off with respect to the head 51.

[0028] As shown in Fig. 6, the net-like member 71 is provided with vertical and horizontal linear portions 73 and 74 that form the mesh openings. The linear portions 73 and 74 have their respective ends fixed to the frame portion 72, and the area surrounded by the frame portion 72 is divided into a large number of pores by these linear portions 73 and 74. The net-like member 71 (linear portions 73 and 74) constitutes a suction surface 81 that sucks the packaging material PF together with the inner peripheral surface of the diameter-expanded portion 53. When the packaging material PF is sucked, a part of the packaging material PF hits the net-like member 71. Then, the excessive suction of the packaging material PF is restricted by the net-like member 71.

[0029] Here, the net-like member 71 (specifically, the linear portions 73 and 74) has flexibility and can be elastically deformed (bent) on the inlet side / rear side of the flow path F. When the packaging material PF is sucked, the sucked packaging material PF hits the net-like member 71, and the net-like member 71 pushed by the packaging material PF bends so as to protrude toward the rear side of the flow path F together with the packaging material PF.

[0030] The elastic modulus of the net-like member 71 (specifically, the linear portions 73 and 74) is smaller (softer) than that of the head 51 (specifically, the diameter-expanded portion 53). This is a measure to prevent the intake holes 51a of the head 51 from narrowing in conjunction with the bending deformation of the net-like member 71. Incidentally, the opening ratio of the net-like member 71 shown in this embodiment is about 80%, suppressing the entry of the packaging material PF into the mesh openings while minimizing the pressure loss in the net-like member 71. Note that the opening ratio of the net-like member 71 may be arbitrarily changed as long as it can prevent the pressure loss in the net-like member 71 from increasing (preventing excessive bending deformation before the packaging material PF hits). For example, it may be set to about 50% to 98%.

[0031] When the net member 71 is bent and deformed together with the packaging material PF, extreme deformation of the packaging material PF is suppressed and the occurrence of a locally large load on the packaging material PF is suppressed. Thereby, the generation of wrinkles described above can be suitably suppressed. Regarding the adsorption force of the work W, the net member 71 and the packaging material PF are defined such that they slightly cross the boundary portion 54 and slightly enter the base portion 52.

[0032] The vertical linear portion 73 and the horizontal linear portion 74 are fixed (welded) to each other, and it is avoided that the size of the mesh (the occurrence of deviation) changes due to the displacement of these linear portions 73, 74. This is a device for suppressing the packaging material PF from entering the mesh when the packaging material PF is adsorbed.

[0033] Next, with reference to FIG. 7, the flow when adsorbing the work W in the boxing process and the change of the adsorption surface 81 will be described.

[0034] When adsorbing the work W, the posture of the robot 15 is changed so that the adsorption pad 42 is lowered toward the conveyor C. Then, when the adsorption pad 42 reaches the adsorption position for adsorbing the work W, the robot 15 is stopped. Specifically, the resistance generated from the work W (specifically, the contained object PD) on the adsorption pad 42 is detected using the force sensor 38, and when the resistance exceeds the reference value, the robot 15 is stopped. Thereby, the head 51 (the diameter-expanded portion 53) of the adsorption pad 42 is in contact with the packaging material PF (see FIG. 7(a)).

[0035] Thereafter, the pump 44 of the suction device 41 is operated to suck in the air in the flow path F (see FIG. 3), thereby generating a negative pressure. As a result, the net-like member 71 is slightly bent and deformed so as to protrude toward the inner side of the flow path F, and a part of the packaging material PF is drawn into the head 51 (see FIGS. 7(a) → 7(b) → 7(c)). At this time, the packaging material PF is sandwiched between the head 51 and the contained object PD, and the rapid suction is suppressed by the friction generated between them and the head 51 and the like. If the packaging material PF is suddenly sucked in, the load generated on the packaging material PF may instantaneously increase, and the wrinkles described above may easily occur. Therefore, starting the suction by the above-described procedure is preferable for suppressing the occurrence of wrinkles.

[0036] The sucked packaging material PF hits the net-like member 71, and the net-like member 71 is pushed by the packaging material PF and bends toward the inner side of the flow path F together with the packaging material PF. At this time, since the net-like member 71 serves as a cushion, an instantaneous increase in the load on the packaging material PF is suppressed. When the net-like member 71 is bent and deformed, the suction surface 81 of the head 51 becomes substantially arc-shaped, and the load on the portion of the packaging material PF that is in contact with the net-like member 71 is reduced.

[0037] In the state where the packaging material PF is sucked, as shown in FIG. 7(c), a part of the packaging material PF enters the base portion 52 beyond the boundary portion 54 between the base portion 52 and the enlarged diameter portion 53. However, the edge portion of the boundary portion 54 is covered by the net-like member 71, and it is suppressed that the packaging material PF is bent at the edge portion, that is, a locally large load is generated. Thereby, the protection function of the packaging material PF is more suitably exhibited.

[0038] When lowering the workpiece W after it has been moved to the transfer box or the like, the operation of the pump 44 is stopped to return the internal pressure in the flow path F to atmospheric pressure. As a result, the adsorption of the workpiece W is released. At this time, the net-like member 71 returns to its original state (flat state) by the elastic force stored in itself. Due to such a change in the state of the net-like member 71, the packaging material PF in contact with the net-like member 71 is pushed toward the opening edge 55 side of the head 51. As a result, the gap between the adsorption surface 81 (particularly the inner peripheral surface of the diameter-expanded portion 53) and the packaging material PF is expanded, promoting the separation between the adsorption surface 81 and the packaging material PF. That is, it suppresses the situation where the packaging material PF remains attached to the adsorption surface 81 even after the adsorption is completed.

[0039] In the case of a robot equipped with an adsorption device, when lowering the workpiece, positive pressure is often applied to the flow path to perform vacuum breaking. However, performing vacuum breaking on a small and lightweight workpiece can be a factor causing the workpiece to be blown away. On the other hand, by setting the flow path to atmospheric pressure and waiting for the workpiece to fall by its own weight, although the above-mentioned inconvenience can be suppressed, the workpiece attached to the head may not fall for a long time or the time may vary. And lengthening the tact time in anticipation of such behavior (adhesion) is a factor leading to a decrease in productivity. Even in view of such circumstances, pushing the packaging material PF toward the opening edge 55 side by the elastic force of the net-like member 71 has technical significance.

[0040] According to the embodiment described in detail above, the following excellent effects can be expected.

[0041] When the packaging material PF is the object to be adsorbed when holding the workpiece W, it is preferable to increase the adsorption force to some extent in order to stably exert the adsorption function (holding function). However, if the adsorption force increases, the load on the packaging material PF also increases, and wrinkles may occur in the packaging material PF due to deformation beyond the elastic range. This is a factor that reduces the yield of the workpiece W (product). In this regard, in the configuration shown in the present embodiment, the packaging material PF drawn into the flow path F during adsorption hits the mesh member 71 during the drawing process. The mesh member 71 pushed by the packaging material PF bends and deforms toward the back side of the flow path F together with the packaging material PF, and the packaging material PF is prevented from deforming greatly instantaneously. Avoiding such a rapid deformation of the packaging material PF is preferable for protecting the packaging material PF. Further, by using the mesh member 71 that bends and deforms toward the back side of the flow path F, it is possible to suppress a large load from being applied to a part of the packaging material PF. Thereby, the protection function of the packaging material PF can be strengthened. For the above reasons, according to the configuration shown in the present embodiment, even if the adsorption force is increased to some extent to stabilize the adsorption function, it is possible to suppress that it causes wrinkles in the packaging material PF, and it is possible to suitably achieve both the stabilization of the adsorption function and the protection of the packaging material PF.

[0042] Since the elastic modulus of the mesh member 71 is smaller than that of the head 51 which is the object to be fixed, it is likely to bend and deform. When the mesh member 71 bends, it is unlikely to cause inconveniences such as the enlarged diameter portion 53 of the head 51 being pulled and the flow path F becoming narrower.

[0043] When the bendable mesh member 71 is made soft (when the elastic modulus is lowered), it becomes easier to bend downward convexly by its own weight by turning the head 51 downward when not adsorbing. Since the state where the mesh member 71 protrudes from the head 51 becomes a factor for the mesh member 71 to get caught, it is not preferable. Therefore, as shown in the present embodiment, by arranging the mesh member 71 at a position away from the opening edge portion 55 of the head 51 toward the back side, it is possible to make it difficult to cause the above inconveniences.

[0044] When it has the base part 52 and the diameter-expanded part 53, when the packaging material PF enters the boundary part 54, wrinkles are likely to occur in the packaging material PF. In this regard, as shown in the present embodiment, by covering the boundary part 54 with the net-like member 71 from the opening edge part 55 side and suppressing the excessive entry of the packaging material PF, the occurrence of wrinkles can be suitably suppressed.

[0045] It is preferable for protecting the work W to configure such that the diameter-expanded part 53 elastically deforms when the head 51 hits the work W. Here, when the diameter-expanded part 53 is elastically deformed so as to be expanded, tension is generated in the net-like member 71 fixed to the diameter-expanded part 53. This tension can be a factor that makes the net-like member 71 difficult to bend. Therefore, by setting the fixing destination of the net-like member 71 closer to the base end part (closer to the boundary part 54) of the diameter-expanded part 53, the tension generated in the net-like member 71 when the diameter-expanded part 53 elastically deforms can be reduced. Thereby, the protective function of the packaging material PF by the net-like member 71 can be more suitably exerted.

[0046] In the net-like member 71 shown in the present embodiment, the vertical and horizontal linear parts 73, 74 are fixed to each other. According to such a configuration, it is possible to avoid the positions of the linear parts 73, 74 from shifting due to the bending deformation of the net-like member 71. Thereby, the uniformity of the mesh can be achieved, and it is possible to make it difficult for the inconvenience that when the mesh deforms by bending, a part of the mesh becomes excessively large and the packaging material PF enters the enlarged part to occur.

[0047] <Other Embodiments> Note that it is not limited to the description content of the above-described embodiment, and for example, it may be implemented as follows. Incidentally, each of the following configurations may be applied to the above-described embodiment individually, or some or all of them may be combined and applied to the above-described embodiment.

[0048] ·In the above embodiment, the mesh member 71 is disposed in the enlarged diameter portion 53 of the head 51, but it is also possible to dispose the mesh member 71 in the base portion 52. When the mesh member 71 is disposed in the base portion 52, it is preferable to dispose the mesh member 71 at a position closer to the boundary portion 54 in the base portion 52, for example, like the suction pad 42X shown in FIG. 8(a).

[0049] ·In the above embodiment, the mesh member 71 is disposed at a position closer to the boundary portion 54 in the enlarged diameter portion 53, but it is also possible to dispose the mesh member 71 at a position closer to the opening edge portion 55 in the enlarged diameter portion 53, like the suction pad 42Y shown in FIG. 8(b). However, in view of the fact that the mesh member 71 has flexibility, the mesh member 71 is likely to bend due to its own weight or the like. The mesh member 71 bending and protruding from the opening edge portion 55 can be a factor for the mesh member 71 to get caught. Further, when the enlarged diameter portion 53 of the head 51 is made soft for the purpose of protecting the work W (the contained object PD), etc., when the head 51 is pressed against the work W, the opening edge portion 55 may be enlarged and the enlarged diameter portion 53 may bend. Such an event is assumed to increase the tension on the mesh member 71 and be a factor for the mesh member 71 to be less likely to bend when the packaging material PF hits the mesh member 71. Considering these circumstances, it has technical significance to dispose the mesh member 71 at a position closer to the boundary portion 54 rather than at a position closer to the opening edge portion 55.

[0050] ·As shown in the suction pad 42C of FIG. 8(c), a stopper portion 58C may be provided at a position on the head 51 that faces the mesh member 71 with a gap therebetween and is on the back side of the mesh member 71. When the mesh member 71 is pushed by the packaging material PF and bends backward, by configuring the mesh member 71 to hit the stopper portion 58C and restrict further bending deformation, excessive deformation (for example, plastic deformation) of the mesh member 71 can be suppressed. Regarding the stopper portion 58C, by configuring it to face the central portion of the mesh member 71, the above effect can be preferably exerted.

[0051] ·In the above embodiment, the net-like member 71 is configured to be fixed to the head 51 by fitting it into the groove portion 56 of the head 51. However, the method of fixing the net-like member 71 is arbitrary. For example, the net-like member 71 may be configured to be fixed to the head 51 using an adhesive or a fixture. It is also possible to integrate it with the head 51 by insert molding.

[0052] ·In the above embodiment, the vertical linear portion 73 and the horizontal linear portion 74 of the net-like member 71 are configured to be fixed to each other. However, the present invention is not limited to this. It is also possible to make the vertical linear portion 73 and the horizontal linear portion 74 non-fixed.

[0053] ·The head 51 shown in the above embodiment has a cylindrical (circular cylindrical) base portion 52 and a diameter-expanded portion 53 provided at one end thereof. However, the diameter-expanded portion 53 can also be omitted. In this case, the net-like member 71 may be disposed inside the base portion 52. Note that the base portion 52 only needs to have intake holes formed therein and is not limited to a cylindrical shape.

[0054] ·In the above embodiment, the pump 44 is operated (the suction is started) in a state where the suction pad 42 is pressed against the packaging material PF of the work W. However, the present invention is not limited to this. It is also possible to configure the suction pad 42 to approach the work W in a state where the pump 44 is operated.

[0055] ·The robot 15 shown in the above embodiment can also be used in a manufacturing factory for medical products or daily necessities. Also, if the robot 15 is to be engaged in the work of holding a work formed by packaging an article with a packaging material, the process to which the robot 15 is applied is arbitrary. For example, it may be applied to a conveying process or an inspection process.

[0056] <Regarding the groups of inventions extracted from the above embodiments> Hereinafter, the features of the invention groups extracted from the above embodiments will be described while showing effects and the like as necessary. In the following, for ease of understanding, the corresponding configurations in the above embodiments are appropriately shown in parentheses or the like, but the invention is not limited to the specific configurations shown in such parentheses or the like.

[0057] Feature 1. An adsorption device (adsorption device 41) that is applied to an industrial robot (robot 15) and adsorbs a workpiece (workpiece W) obtained by packaging an article (accommodated object PD) using a packaging material (packaging material PF), an adsorption head (head 51 of adsorption pad 42) that contacts the packaging material of the workpiece, a suction pump (pump 44), and a pipe section (pipe section 43) connecting the adsorption head (air intake hole 51a) and the pump, and comprising: The adsorption head is provided with a net-like member (net-like member 71) that forms a planar shape intersecting a flow path (air intake hole 51a) formed in the adsorption head and is bendable and deformable in the suction direction by the pump.

[0058] When the packaging material is the object to be adsorbed during the adsorption of the workpiece, it is preferable to increase the adsorption force to a certain extent in order to stably exert the adsorption function. However, if the adsorption force increases, the load on the packaging material also increases, and wrinkles may occur on the packaging material due to deformation beyond the elastic range. This is a factor that reduces the yield of the workpiece (product). In this regard, in the configuration shown in this feature, the packaging material drawn into the flow path during adsorption hits the mesh member during the drawing process. The mesh member pushed by the packaging material bends and deforms together with the packaging material toward the back side of the flow path, and the packaging material is prevented from deforming greatly instantaneously. Avoiding such rapid deformation of the packaging material is preferable for protecting the packaging material. In addition, by using a mesh member that bends and deforms toward the back side of the flow path, it is possible to suppress a large load from being applied to a part of the packaging material. Thereby, the protection function of the packaging material can be strengthened. For the above reasons, according to the configuration shown in this feature, even if the adsorption force is increased to a certain extent to stabilize the adsorption function, it can be suppressed that this causes wrinkles in the packaging material, and the stabilization of the adsorption function and the protection of the packaging material can be suitably achieved simultaneously.

[0059] Feature 2. The adsorption device according to Feature 1, wherein the mesh member is configured to be bent and deformed so as to protrude in the suction direction together with the suctioned packaging material by being pushed in the suction direction by the suctioned packaging material.

[0060] As shown in this feature, if the configuration is such that the mesh member pushed by the suctioned packaging material bends and deforms so as to protrude in the suction direction together with the packaging material, the effects shown in Feature 1 can be suitably exerted.

[0061] Feature 3. The suction head is formed so as to be elastically deformable when it hits the workpiece, The adsorption device according to Feature 1 or Feature 2, wherein the mesh member is fixed to the suction head, and the elastic modulus of the mesh member is smaller than the elastic modulus of the suction head.

[0062] Since the elastic modulus of the mesh member, which is the object to be fixed, is smaller than that of the suction head, it is likely to undergo bending deformation. When the mesh member bends, it is less likely to cause inconveniences such as the suction head being pulled and the flow path becoming narrower.

[0063] Feature 4. The adsorption device according to any one of Features 1 to 3, wherein the mesh member is disposed at a position deeper in the suction direction than the opening edge portion (opening edge portion 55) of the suction head.

[0064] When the bendable mesh member is softened (when the elastic modulus is lowered), when the suction head is directed downward during non-suction, it is more likely to bend downward convexly due to its own weight. Since the state where the mesh member protrudes from the suction head becomes a factor for the mesh member to get caught, it is not preferable. Therefore, as shown in this feature, by disposing the mesh member at a position away from the opening edge of the suction head toward the back side, it is possible to make it less likely to cause the above inconveniences.

[0065] Feature 5. The suction head has a cylindrical base portion (base portion 52) and a diameter-expanded portion (diameter-expanded portion 53) provided at one end of the base portion and formed such that the inner diameter gradually increases toward the tip side of the suction head. The boundary (boundary portion 54) between the base portion and the diameter-expanded portion is covered from the tip side of the suction head by the mesh member. The adsorption device according to any one of Features 1 to 3.

[0066] When having a base portion and a diameter-expanded portion, when the packaging material enters the boundary therebetween, wrinkles are likely to occur in the packaging material. In this regard, as shown in this feature, by covering the boundary from the opening side with the mesh member to suppress excessive entry of the packaging material, it is possible to suitably suppress the occurrence of wrinkles.

[0067] Feature 6. The diameter-expanded portion is formed so as to be elastically deformable when hitting the workpiece. The mesh member is fixed to a portion near the boundary at the diameter-expanded portion. The adsorption device according to Feature 5.

[0068] It is preferable for protecting the workpiece that the diameter-expanding portion is elastically deformed when the suction head contacts the workpiece. Here, if the diameter-expanding portion is elastically deformed by being expanded, tension is generated in the net-like member fixed to the diameter-expanding portion. This tension can be a factor that makes the net-like member difficult to bend. Therefore, by making the fixing point of the net-like member be a portion near the boundary in the diameter-expanding portion, the tension generated in the net-like member when the diameter-expanding portion is elastically deformed can be reduced. Thereby, the protective function of the packaging material by the net-like member can be more suitably exhibited.

[0069] Feature 7. The suction device according to any one of Features 1 to 6, wherein the net-like member is characterized in that the vertical and horizontal linear portions constituting the net-like member are fixed to each other.

[0070] According to the configuration shown in this feature, it is possible to avoid the position of the linear member from shifting due to the bending deformation of the net-like member. Thereby, the uniformity of the mesh can be achieved, and it is possible to hardly cause inconveniences such as a part of the mesh becoming excessively large during bending deformation and the packaging material entering the enlarged part.

[0071] Feature 8. The suction device according to any one of Features 1 to 7, wherein the suction head is provided with a regulating portion (stopper portion 58C) that regulates the bending deformation of the net-like member exceeding a predetermined amount by contacting the net-like member from the back side of the flow path.

[0072] Even if a large force is instantaneously applied to the net-like member, it is possible to avoid the occurrence of bending exceeding the assumption. This is preferable for stably exhibiting the protective function shown in Feature 1.

[0073] Feature 9. The suction device according to any one of Features 1 to 8, wherein when the suction by the pump is completed, the net-like member returns to the state before bending deformation by its own elastic force.

[0074] As shown in this feature, if the net-like member returns to its state before deformation by its own elastic force at the end of adsorption (suction), it is possible to reduce the occurrence of inconveniences such as the packaging material remaining attached to the suction head.

[0075] Feature 10. An industrial robot comprising an arm (arm 31) formed with a plurality of joint parts, A suction head (suction pad 42) that is attached to the tip of the arm and contacts the packaging material when holding a workpiece (workpiece W) formed by packaging an article (accommodated object PD) using the packaging material (packaging material PF), A pipe section (pipe section 43) that is attached to the arm and connects the suction head and a suction pump (pump 44), An industrial robot having a suction device (suction device 41) having the above, The suction head is provided with a net-like member (net-like member 71) that forms a planar shape intersecting a flow path formed in the suction head and is capable of bending and deforming, The net-like member is configured to bend and deform so as to protrude in the suction direction together with the packaging material by being pushed in the suction direction by the sucked packaging material.

[0076] When the packaging material is the object to be adsorbed during the adsorption of the workpiece, it is preferable to increase the adsorption force to a certain extent in order to stably exert the adsorption function. However, if the adsorption force increases, the load on the packaging material also increases, and wrinkles may occur on the packaging material due to deformation beyond the elastic range. This is a factor that reduces the yield of the workpiece (product). In this regard, in the configuration shown in this feature, the packaging material drawn into the flow path during adsorption hits the mesh member during the drawing process. The mesh member pushed by the packaging material bends and deforms toward the back of the flow path together with the packaging material, and the packaging material is prevented from deforming greatly instantaneously. Avoiding such rapid deformation of the packaging material is preferable for protecting the packaging material. In addition, by using a mesh member that bends and deforms toward the back of the flow path, it is possible to suppress a large load from being applied to a part of the packaging material. Thereby, the protection function of the packaging material can be strengthened. For the above reasons, according to the configuration shown in this feature, even if the adsorption force is increased to a certain extent to stabilize the adsorption function, it can be suppressed from causing wrinkles in the packaging material, and the stabilization of the adsorption function and the protection of the packaging material can be suitably achieved simultaneously.

Explanation of Signs

[0077] 10…Robot system, 15…Robot as an industrial robot, 31…Arm, 41…Adsorption device, 42…Adsorption pad, 43…Piping section, 44…Pump, 51…Head, 51a…Air intake hole, 52…Base section, 53…Diameter-expanded section, 54…Boundary portion, 55…Opening edge portion, 58C…Stopper section, 71…Mesh member, 73,74…Linear sections, 81…Adsorption surface, F…Flow path, PD…Contents as an article, PF…Packaging material, W…Workpiece.

Claims

1. An adsorption device that is applied to an industrial robot and adsorbs a workpiece obtained by packaging an article using a packaging material, comprising: an adsorption head that contacts the packaging material of the workpiece; a suction pump; a pipe section connecting the adsorption head and the pump; and the adsorption head is provided with a net-like member that forms a planar shape intersecting a flow path formed in the adsorption head and is bendable and deformable in the suction direction by the pump.

2. The adsorption device according to claim 1, wherein the net-like member is configured to be bent and deformed so as to protrude in the suction direction together with the packaging material when pushed in the suction direction by the sucked packaging material.

3. The adsorption head has a cylindrical base portion and a diameter-expanded portion provided at one end side of the base portion and formed such that the inner diameter gradually increases toward the tip, and the boundary between the base portion and the diameter-expanded portion is covered from the tip side of the adsorption head by the net-like member. The adsorption device according to claim 1 or claim 2.

4. The diameter-expanded portion is formed to be elastically deformable when hitting the workpiece, and the net-like member is fixed to a portion near the boundary in the diameter-expanded portion. The adsorption device according to claim 3.

5. An industrial robot comprising an arm formed with a plurality of joint portions, an adsorption head attached to the tip of the arm and contacting the packaging material when holding a workpiece obtained by packaging an article using a packaging material; a pipe section attached to the arm and connecting the adsorption head and a suction pump; and having an adsorption device, the adsorption head is provided with a net-like member that forms a planar shape intersecting a flow path formed in the adsorption head and is bendable and deformable, and the net-like member is configured to be bent and deformed so as to protrude in the suction direction together with the packaging material when pushed in the suction direction by the sucked packaging material.

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