JP2019010691A - Hand of industrial robot and industrial robot - Google Patents

Abstract

To provide a hand capable of contacting all the suction mechanisms with a carrying object even when the carrying object is hardly deflective between an adjacent inside fork and an outside fork, while simplifying a suction route of air of the suction mechanism installed in four forks.SOLUTION: In a hand 3, when installing a suction mechanism 22 in the same position of four forks 18, 19, a suction route of air of four suction mechanisms 22 becomes common. Assuming that quantity capable of moving a suction part in the vertical direction to a floating mechanism when sucking a carrying object 2 in the most inclined state, as a maximum movable quantity, in an area where a height difference of an upper surface of the forks 18, 19 to a reference height in the X direction becomes the maximum movable quantity or less, a suction mechanism 22B is installed in the four forks 18, 19, and in an area where the height difference of the upper surface of the forks 18, 19 to the reference height exceeds the maximum movable quantity, a suction mechanism 22C is installed in two forks 19.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an industrial robot hand for transporting a transport object. The present invention also relates to an industrial robot provided with this hand.

  Conventionally, an industrial robot that transports a glass substrate for a liquid crystal display is known (for example, see Patent Document 1). The industrial robot hand described in Patent Literature 1 includes two forks formed in a straight line. The fork is made of, for example, a resin containing carbon fiber and formed by molding. A plurality of suction mechanisms (suction pads) for vacuum-sucking a glass substrate placed on the fork are attached to the front end side of the fork at a predetermined interval in the longitudinal direction of the fork. Moreover, the hand described in Patent Document 1 includes a fork pitch changing mechanism that changes the pitch of two forks.

JP 2017-19061 A

  In recent years, a relatively wide conveyance object has begun to be used as a conveyance object such as a glass substrate conveyed by an industrial robot. In other words, a conveyance object having a wide width in a direction orthogonal to the longitudinal direction of the fork has begun to be used. When a relatively wide conveyance object is conveyed by a hand having two forks, such as an industrial robot hand described in Patent Document 1, between two forks or outside of two forks. Thus, the conveyance object is greatly bent, and the conveyance object being conveyed becomes unstable. Therefore, the inventor of the present application is examining the structure of a hand having four forks.

  Of the four forks, two forks arranged on the inner side in the direction orthogonal to the longitudinal direction of the fork are taken as inner forks, and the remaining two forks arranged outside are taken as outer forks. The inventor of the present application uses a fork pitch changing mechanism for changing the pitch of the two inner forks and two of the two forks so that a plurality of types of transfer objects having different sizes can be transferred in a hand having four forks. We are considering adopting a fork pitch changing mechanism that changes the pitch of the outer fork. Furthermore, in order to simplify the air suction path of the suction mechanism attached to the four forks, the inventor of the present application uses the air suction path of the suction mechanism attached to the same position of the four forks in the longitudinal direction of the fork. We are considering making it common.

  However, according to the study of the present inventor, for example, there is a relatively rigid transport object such as a transport object in which two glass substrates are bonded and liquid crystal is injected between the two glass substrates. If the distance between the inner fork and the outer fork adjacent to each other is reduced and the object to be transported is less likely to bend between the adjacent inner fork and the outer fork, Depending on the accuracy of the fork parts, the height of the suction mechanism attached to the inner fork and the suction mechanism attached to the outer fork adjacent to the inner fork, and the suction mechanism attached to the inner fork are the same in the longitudinal direction of the fork Because the height of the suction mechanism arranged at the position varies, the inner fork is sucked in a predetermined area in the longitudinal direction of the fork. Adsorption mechanism of structure or outer fork revealed that there may not contact the object to be transported.

  When the suction path of the suction mechanism attached to the same position of the four forks in the longitudinal direction of the forks is common, the suction mechanism of the inner fork or the outer fork is in a predetermined region in the longitudinal direction of the fork. If the suction mechanism is not in contact with the object to be transported, the transport object cannot be sucked by the suction mechanism of the inner fork and the suction mechanism of the outer fork in that region.

  Therefore, an object of the present invention is to provide a plurality of suction mechanisms that are provided with four forks, two inner forks and two outer forks, and that vacuum-suck the lower surface of an object to be transported placed on the upper surface side of the fork. In an industrial robot hand comprising: a case where a conveyance object is difficult to bend between an inner fork and an outer fork adjacent to each other while simplifying an air suction path of an adsorption mechanism attached to four forks. Another object of the present invention is to provide a hand capable of bringing all the suction mechanisms into contact with the object to be transported even when the component accuracy of the fork is low. Moreover, the subject of this invention is providing the industrial robot provided with this hand.

  In order to solve the above-described problems, an industrial robot hand according to the present invention is an industrial robot hand that conveys a conveyance object. It has a plurality of suction mechanisms that vacuum-suck the lower surface of the object to be transported placed on the upper surface of the fork, and the suction mechanism can be tilted and moved up and down with respect to the fork and the fork. The first suction mechanism as the suction mechanism is attached at the same position in the longitudinal direction of the fork, and is provided in the longitudinal direction of the fork. The direction orthogonal to the vertical direction is the orthogonal direction, and each of the two forks arranged inside the orthogonal direction among the four forks is an inner fork. Assuming that each of the remaining two forks arranged on the side is an outer fork, when the suction mechanism is attached to the two inner forks and the two outer forks at the same position in the longitudinal direction of the forks, two The air suction path of the suction mechanism attached to the inner fork of the two and the air suction path of the suction mechanism attached to the two outer forks are common, and the first suction mechanism on the upper surface of the fork is attached. The amount of the suction part that can be moved in the vertical direction with respect to the floating mechanism when the suction part picks up the object to be transported that is most inclined in design with respect to the upper surface of the fork. In the region where the height difference of the top surface of the fork with respect to the reference height is less than or equal to the maximum movable amount in the longitudinal direction of the fork, In the region where the difference in height of the upper surface of the fork with respect to the reference height exceeds the maximum movable amount in the longitudinal direction of the fork and the two outer forks, only the two inner forks or two The suction mechanism is attached only to the outer fork of the.

  In the industrial robot hand of the present invention, when the suction mechanism is attached to the two inner forks and the two outer forks at the same position in the longitudinal direction of the fork, the suction mechanism attached to the two inner forks The air suction path and the air suction path of the suction mechanism attached to the two outer forks are common. Therefore, in the present invention, it is possible to simplify the air suction path of the suction mechanism attached to the four forks.

  In the present invention, in the longitudinal direction of the fork, the suction mechanism is attached to the two inner forks and the two outer forks in a region where the height difference of the upper surface of the fork with respect to the reference height is less than the maximum movable amount. However, in the longitudinal direction of the fork, in the region where the height difference of the top surface of the fork with respect to the reference height exceeds the maximum movable amount, the suction mechanism is attached only to the two inner forks or only to the two outer forks. ing. Therefore, in the present invention, even if the object to be transported is difficult to bend between the inner fork and the outer fork adjacent to each other, and even when the fork component accuracy is low, all the suction mechanisms are transported. It becomes possible to contact an object.

  In the present invention, for example, the floating mechanism includes a holding member that is fixed to the fork and holds the suction portion so as to be tiltable and vertically movable, and a biasing member that biases the suction portion upward with respect to the holding member. And an annular rubber plate connecting the adsorbing part and the holding member, the outer peripheral side portion of the rubber plate is fixed to the holding member over the entire circumferential direction of the rubber plate, and the inner peripheral side portion of the rubber plate is The rubber plate is fixed to the suction portion over the entire circumferential direction of the rubber plate, and the maximum movable amount is determined by the holding member when the suction portion sucks the conveyance object that is in the design most inclined with respect to the upper surface of the fork. On the other hand, this is the amount by which the suction part can move in the vertical direction.

  In the present invention, the suction portion is formed with a suction hole for sucking the object to be transported in the suction portion, and a portion surrounded by the suction portion, the holding member, and the rubber plate is a sealed space where the suction hole is connected. In the holding member, a second suction hole connected to the sealed space is formed, and when the air is sucked by the suction mechanism connected to the second suction hole and the conveyance object is sucked to the suction portion, It is preferable that the sealed space has a negative pressure and the adsorbing portion moves downward against the urging force of the urging member. If comprised in this way, if an adsorption | suction part adsorb | sucks a conveyance target object and an adsorption | suction part moves below, an adsorption | suction part will become hard to wobble with respect to a fork. Therefore, it is possible to stabilize the state of the transport object mounted on the hand when transporting the transport object.

  In the present invention, in the longitudinal direction of the fork, it is preferable that the suction mechanism is attached only to the two outer forks in a region where the height difference of the upper surface of the fork with respect to the reference height exceeds the maximum movable amount. With this configuration, the distance between the suction mechanisms in the orthogonal direction can be increased as compared with the case where the suction mechanisms are attached to only the two inner forks. It becomes possible to stabilize the state of an object. Further, in the longitudinal direction of the fork, if the suction mechanism is attached only to the two inner forks in a region where the height difference of the upper surface of the fork with respect to the reference height exceeds the maximum movable amount, the two inner forks In the case of close contact, there is a possibility that the suction mechanism of one inner fork cannot be brought into contact with the object to be conveyed. With this configuration, even if the two inner forks are in close contact, the two outer forks This suction mechanism can be brought into contact with the object to be conveyed.

  In the present invention, for example, two suction mechanisms including the first suction mechanism are attached to the two inner forks, and three suction mechanisms including the first suction mechanism are attached to the two outer forks. The first suction mechanism is disposed on the most distal end side of the four forks, and the second suction mechanism as the second suction mechanism disposed second from the front ends of the four forks is the same position in the longitudinal direction of the forks. If the suction mechanism excluding the first suction mechanism and the second suction mechanism, which is disposed on the outer fork, is a third suction mechanism, the four suction paths and the four first suction mechanisms are used. The air suction path of the two adsorption mechanisms is a common first suction path, and the air suction paths of the two third adsorption mechanisms are different second suction paths from the first suction path. . In this case, since the air suction paths of the four first suction mechanisms and the air suction paths of the four second suction mechanisms are a common first suction path, they are attached to the four forks. It is possible to further simplify the air suction path of the suction mechanism.

  The hand of the present invention can be used in an industrial robot including an arm that is pivotally connected to the distal end side and a main body that is pivotally connected to the proximal end side of the arm. In this industrial robot, while the air suction path of the suction mechanism attached to the four forks is simplified, the object to be transported is not easily bent between the inner fork and the outer fork adjacent to each other. Even if the fork component accuracy is low, all the suction mechanisms can be brought into contact with the object to be conveyed.

  As described above, in the present invention, the air suction path of the suction mechanism attached to the four forks is simplified, and the object to be conveyed is not easily bent between the inner fork and the outer fork adjacent to each other. In addition, even if the fork component accuracy is low, all the suction mechanisms can be brought into contact with the object to be conveyed.

It is a top view of the industrial robot concerning an embodiment of the invention. It is a side view of the industrial robot shown in FIG. It is a top view of the hand shown in FIG. It is a top view for demonstrating the structure inside the base of the hand shown in FIG. It is a top view for demonstrating operation | movement of the fork shown in FIG. It is sectional drawing of the adsorption | suction mechanism shown in FIG. 3, and a fork. FIG. 7 is a plan view of the suction plate shown in FIG. 6. It is a figure for demonstrating the reference | standard of arrangement | positioning of the several adsorption | suction mechanism shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Overall configuration of industrial robot)
FIG. 1 is a plan view of an industrial robot 1 according to an embodiment of the present invention. FIG. 2 is a side view of the industrial robot 1 shown in FIG.

  The industrial robot 1 of this embodiment (hereinafter referred to as “robot 1”) is a horizontal articulated robot for transporting a predetermined transport object 2. The transport object 2 of this embodiment is, for example, a liquid crystal display in the middle of manufacturing in which two glass substrates are bonded together and liquid crystal is injected between the two glass substrates, and the rigidity of the transport object 2 is compared. It is getting higher. The conveyance object 2 is formed in a rectangular flat plate shape. The robot 1 is used by being incorporated in a liquid crystal display manufacturing system, for example. The robot 1 carries out, for example, the conveyance object 2 accommodated in the cassette, or carries the conveyance object 2 into the cassette. Further, the robot 1 of the present embodiment can transport a plurality of types of transport objects 2 having different sizes (see FIG. 3).

  The robot 1 includes two hands 3 on which the object 2 to be transported is mounted, two arms 4 to which the two hands 3 are connected to the distal end side, and a main body unit that supports the two arms 4. 5 and a base 6 that supports the main body 5 movably in the horizontal direction. The main body 5 constitutes a base that supports the base end side of the arm 4 and can move up and down, a support frame 8 that supports the arm support 7 so as to move up and down, and a lower end portion of the main body 5. 6, a base 9 that can move horizontally with respect to 6, and a revolving frame 10 that is fixed to the lower end of the support frame 8 and that can rotate with respect to the base 9.

  The arm 4 is composed of two arm parts, a first arm part 12 and a second arm part 13. The base end side of the first arm portion 12 is rotatably connected to the arm support 7. That is, the base end side of the arm 4 is rotatably connected to the main body 5. The proximal end side of the second arm portion 13 is rotatably connected to the distal end side of the first arm portion 12. The hand 3 is rotatably connected to the distal end side of the second arm portion 13. That is, the hand 3 is rotatably connected to the distal end side of the arm 4. The robot 1 includes two arm drive mechanisms that extend and contract each of the two arms 4.

  The support frame 8 holds the hand 3 and the arm 4 through the arm support 7 so as to be movable up and down. The support frame 8 includes a columnar first support frame 14 that holds the arm support 7 so as to be movable up and down, and a columnar second support frame 15 that holds the first support frame 14 so as to be movable up and down. The robot 1 moves the arm support 7 up and down relative to the first support frame 14, the lift mechanism that raises and lowers the first support frame 14 relative to the second support frame 15, and the first support frame 14 up and down. And a guide mechanism for guiding the arm support 7 in the vertical direction.

  The lower end of the second support frame 15 is fixed to the revolving frame 10. As described above, the revolving frame 10 is rotatable with respect to the base 9. The robot 1 includes a turning mechanism for turning the turning frame 10 with respect to the base 9. The base 9 can be moved horizontally with respect to the base 6 as described above. The robot 1 includes a horizontal movement mechanism that horizontally moves the base 9 with respect to the base 6.

(Hand structure)
FIG. 3 is a plan view of the hand 3 shown in FIG. FIG. 4 is a plan view for explaining the internal structure of the base 17 of the hand 3 shown in FIG. FIG. 5 is a plan view for explaining the operation of the forks 18 and 19 shown in FIG.

  The hand 3 includes a base portion 17 that is rotatably connected to the distal end side of the second arm portion 13, and a plurality of forks 18 and 19 on which the transport object 2 is placed on the upper surface side. The hand 3 of this embodiment includes a total of four forks 18, 19 including two forks 18 and two forks 19. In addition, the hand 3 is fixed to the upper surface side of the forks 18 and 19 and a plurality of mounting members 21 on which the transport target 2 is mounted, and a transport target 2 mounted on the mounting member 21 (that is, the transport target 2). And a plurality of suction mechanisms 22 for vacuum-sucking the lower surface of the conveyance object 2) placed on the upper surface side of the forks 18 and 19.

  The base portion 17 is formed in a hollow and substantially flat rectangular parallelepiped shape with a thin vertical thickness. The forks 18 and 19 are formed in a straight line. The four forks 18 and 19 protrude from the base portion 17 in the same horizontal direction. Further, the four forks 18 and 19 are arranged in parallel to each other. When the longitudinal direction of the forks 18 and 19 (X direction in FIG. 3 etc.) is “front-rear direction” and the Y direction in FIG. 3 perpendicular to the up-down direction and the front-rear direction is “left-right direction”, the two forks 18 Are arranged on the inner side in the left-right direction, and the two forks 19 are arranged on the outer side in the left-right direction. The left-right direction (Y direction) in this embodiment is an orthogonal direction orthogonal to the longitudinal direction of the forks 18 and 19 and the up-down direction. Each of the two forks 18 is an inner fork disposed inside the orthogonal direction, and each of the two forks 19 is an outer fork disposed outside the orthogonal direction.

  The forks 18 and 19 are formed of a resin containing carbon fibers. The forks 18 and 19 are formed by molding. Further, the forks 18 and 19 are formed in a hollow shape and are formed in an elongated substantially rectangular parallelepiped shape. The upper and lower surfaces of the forks 18 and 19 are flat. Further, the left and right side surfaces of the forks 18 and 19 are planes orthogonal to the left-right direction. The thicknesses of the forks 18 and 19 in the vertical direction are gradually reduced from the base ends of the forks 18 and 19 toward the tip (see FIG. 2).

  The mounting member 21 is made of resin. The mounting member 21 is formed in a substantially rectangular flat plate shape. A plurality of mounting members 21 are fixed to the upper surfaces of the two forks 18 and the upper surfaces of the two forks 19, respectively. The plurality of placement members 21 are arranged in the entire range of the forks 18 and 19 in the range in which the conveyance object 2 can be placed in the front-rear direction. That is, as shown in FIG. 3, the plurality of placement members 21 are arranged in a row in the front-rear direction so as to be continuous over the entire range of the fork 18, 19 in which the conveyance object 2 can be placed.

  In the fork 18, the suction mechanism 22 is attached at two locations on the tip side of the fork 18. In the fork 19, the suction mechanism 22 is attached to a total of three locations, two locations on the tip side of the fork 19 and one location in the middle of the fork 19 in the front-rear direction. At the place where the suction mechanism 22 is attached, the interval between the placement members 21 in the front-rear direction is wide, and the suction mechanism 22 is disposed between the placement members 21 in the front-rear direction. The detailed configuration and arrangement of the suction mechanism 22 will be described later.

  The base end portions of the forks 18 and 19 are disposed inside a base portion 17 formed in a hollow shape. As shown in FIG. 4, a fork pitch changing mechanism 26 that changes the pitch of the two forks 18 in the left-right direction and a fork pitch change that changes the pitch of the two forks 19 in the left-right direction are provided inside the base portion 17. A mechanism 27 is arranged. That is, the hand 3 includes fork pitch changing mechanisms 26 and 27.

  The fork pitch changing mechanism 26 includes a motor 29 as a drive source, a screw member 30 connected to the output shaft of the motor 29, a nut member (not shown) fixed to one of the two forks 18, A nut member (not shown) fixed to the other of the two forks 18. The fork pitch changing mechanism 27 is configured in the same manner as the fork pitch changing mechanism 26. That is, the fork pitch changing mechanism 27 includes a motor 34 configured similarly to the motor 29, a screw member 35 configured similar to the screw member 30, and a nut member fixed to one of the two forks 19. (Not shown) and a nut member (not shown) fixed to the other of the two forks 19 are provided.

  The screw members 30 and 35 are formed in an elongated rod shape. The screw members 30 and 35 are disposed so that the axial direction of the screw members 30 and 35 coincides with the left-right direction, and are rotatably supported by the base portion 17. The screw members 30, 35 include forward screw portions 30 a, 35 a that constitute one end side of the screw members 30, 35 and reverse screw portions 30 b, 35 b that constitute the other end side of the screw members 30, 35. The forward screw portions 30a and 35a are formed with forward screws, and the reverse screw portions 30b and 35b are formed with reverse screws.

  The nut member fixed to one fork 18 is engaged with the forward screw portion 30a, and the nut member fixed to the other fork 18 is engaged with the reverse screw portion 30b. Similarly, the nut member fixed to one fork 19 is engaged with the forward screw portion 35a, and the nut member fixed to the other fork 19 is engaged with the reverse screw portion 35b. The two forks 18 and the two forks 19 are guided in the left-right direction by two common guide rails 36. The guide rail 36 is fixed to the base portion 17 so that the longitudinal direction of the guide rail 36 coincides with the left-right direction. Guide blocks (not shown) that engage with the guide rails 36 are attached to the forks 18 and 19.

  In the fork pitch changing mechanism 26, when the motor 29 rotates and the screw member 30 rotates, one fork 18 and the other fork 18 move by the same amount in the left and right reverse directions, and the left and right direction of the two forks 18 The pitch of is changed. Similarly, in the fork pitch changing mechanism 27, when the motor 34 rotates and the screw member 35 rotates, one fork 19 and the other fork 19 move by the same amount in the left and right opposite directions, and the two forks 19 The left and right pitch is changed.

  In this embodiment, when the size of the transfer object 2 to be transferred by the robot 1 is determined, the fork pitch changing mechanism 26 has two fork pitch change mechanisms 26 as necessary before the transfer operation of transferring the transfer object 2 by the robot 1. The fork pitch changing mechanism 27 changes the left-right pitch of the two forks 19 as necessary. That is, the fork pitch changing mechanisms 26 and 27 do not change the left and right pitches of the forks 18 and 19 during the transfer operation of the transfer object 2 by the robot 1. The fork pitch changing mechanisms 26 and 27 change the left and right pitches of the forks 18 and 19 according to the size of the transport object 2 transported by the robot 1, for example, as shown in FIG.

(Configuration of adsorption mechanism)
6 is a cross-sectional view of the suction mechanism 22 and the forks 18 and 19 shown in FIG. FIG. 7 is a plan view of the suction plate 40 shown in FIG.

  On the top surfaces of the forks 18 and 19, through holes 18a and 19a in which the suction mechanism 22 is disposed are formed. The through holes 18a and 19a penetrate the top surfaces of the forks 18 and 19 in the vertical direction. The suction mechanism 22 includes a suction unit 39 that sucks the conveyance object 2. The suction unit 39 includes a suction plate (suction pad) 40 that contacts the lower surface of the transport target object 2 and sucks the transport target object 2, and a fixing member 41 that fixes the suction plate 40 to the upper end side. .

  Further, the suction mechanism 22 includes a floating mechanism 42 that supports the suction portion 39 so as to be tiltable with respect to the forks 18 and 19. That is, the floating mechanism 42 supports the suction portion 39 so that the suction portion 39 can be inclined with respect to the forks 18 and 19. The floating mechanism 42 supports the suction portion 39 so as to be movable up and down with respect to the forks 18 and 19.

  The fixing member 41 includes a first fixing member 58 to which the suction plate 40 is fixed, and a second fixing member 59 that forms the central portion of the fixing member 41. The second fixing member 59 is formed in a columnar shape with a flange having a flange portion 59a. The flange portion 59 a constitutes the lower end portion of the second fixing member 59. At the center of the second fixing member 59, a suction hole 41d for sucking the conveyance object 2 to the suction plate 40 is formed. The suction hole 41d penetrates the second fixing member 59 in the vertical direction.

  The first fixing member 58 includes an upper end portion 58 a that forms an upper end portion of the first fixing member 58 and a lower end portion 58 b that forms a lower end portion of the first fixing member 58. At the center of the first fixing member 58, a through hole 58c in which the upper end side portion of the second fixing member 59 is disposed is formed. The upper end 58a is formed in a substantially disc shape. The lower end 58b is formed in a substantially truncated cone shape whose outer diameter gradually increases toward the upper side. The upper end of the lower end 58b is connected to the lower end of the upper end 58a. The outer diameter of the upper end 58a is larger than the outer diameter of the upper end of the lower end 58b. The through hole 58c penetrates the first fixing member 58 in the vertical direction. When viewed in the vertical direction, the center of the upper end portion 58a, the center of the lower end portion 58b, and the center of the through hole 58c coincide.

  The adsorption plate 40 is made of a resin such as polyether ether ketone. Further, the suction plate 40 is formed in a disc shape. The upper surface of the suction plate 40 is a flat surface, and the conveyance object 2 is placed on the upper surface of the suction plate 40. The suction plate 40 is formed with a plurality of suction holes 40 a for sucking the conveyance object 2 to the suction plate 40. The plurality of suction holes 40a penetrate the suction plate 40 in the vertical direction. Moreover, the several suction hole 40a is arrange | positioned like the several shower hole of a shower head.

  On the lower surface of the suction plate 40, a suction recess 40 b connected to the lower ends of the plurality of suction holes 40 a is formed so as to be recessed upward. The suction plate 40 is fixed to the upper surface of the upper end portion 58a of the first fixing member 58 with a screw (not shown) so that the center of the suction plate 40 and the center of the suction hole 41d coincide when viewed from above and below. Has been. The suction hole 40a and the recess 40b are connected to the suction hole 41d.

  The floating mechanism 42 is fixed to the forks 18 and 19 and holds the suction portion 39 so as to be tiltable and vertically movable, an annular rubber plate 44 that connects the suction portion 39 and the holding member 43, and a holding mechanism A compression coil spring 45 is provided as a biasing member that biases the suction portion 39 upward with respect to the member 43. The holding member 43 includes a first holding member 48 disposed on the upper surface side of the forks 18 and 19 and a second holding member 49 disposed inside the forks 18 and 19 formed in a hollow shape. In this embodiment, the first holding member 48 and the second holding member 49 constitute the holding member 43. The first holding member 48 and the second holding member 49 are formed separately.

  The first holding member 48 is formed in a flat and substantially rectangular parallelepiped shape with a small thickness in the vertical direction. At the center of the first holding member 48, a through hole 48a penetrating in the vertical direction is formed. The inner peripheral surface of the through hole 48a is an inclined surface whose inner diameter gradually increases toward the upper side. On the upper surface of the first holding member 48, a circular recess 48b that is recessed downward is formed. When viewed from the top-bottom direction, the center of the recess 48b coincides with the center of the through hole 48a. The upper end of the through hole 48a is connected to the center of the recess 48b.

  A step is formed on the lower surface of the first holding member 48, and the outer peripheral side portion of the lower surface of the first holding member 48 is disposed above the inner peripheral side portion of the lower surface of the first holding member 48. . The outer peripheral side portion of the lower surface of the first holding member 48 is in contact with the upper surfaces of the forks 18 and 19. The first holding member 48 is fixed to the upper surfaces of the forks 18 and 19 from above. A part of the first holding member 48 is disposed in the through holes 18a and 19a.

  The second holding member 49 is formed in a substantially rectangular parallelepiped block shape. The second holding member 49 is smaller than the first holding member 48 in the left-right direction. The second holding member 49 is fixed to the upper surfaces of the forks 18 and 19 from below. On the upper surface of the second holding member 49, a circular concave portion 49 a that is greatly depressed downward is formed. When viewed from above and below, the center of the recess 49 a coincides with the center of the second holding member 49. A suction hole 49b connected to the center of the bottom surface of the recess 49a is formed in the lower end portion of the second holding member 49. The suction hole 49b of this embodiment is a second suction hole.

  The suction hole 49b is composed of a portion that is recessed downward from the center of the bottom surface of the concave portion 49a, and a portion that extends from the lower end of this portion to one side in the front-rear direction, and suction when viewed from the left-right direction. The shape of the hole 49b is an L shape. One end of the suction hole 49b is connected to the recess 49a, and a suction mechanism (not shown) such as a vacuum pump is connected to the other end of the suction hole 49b via a predetermined pipe.

  The rubber plate 44 is made of, for example, silicon rubber. The rubber plate 44 is formed in an annular shape. A second fixing member 59 is inserted through the inner peripheral side of the rubber plate 44. The outer peripheral side portion of the rubber plate 44 is fixed to the holding member 43 over the entire circumferential direction of the rubber plate 44. Specifically, the outer peripheral side portion of the rubber plate 44 is fixed to the holding member 43 by the lower surface of the first holding member 48 and the upper surface of the second holding member 49. The outer peripheral portion of the rubber plate 44 is sandwiched between the inner peripheral portion of the lower surface of the first holding member 48 and the upper surface of the second holding member 49.

  An inner peripheral side portion of the rubber plate 44 is fixed to the fixing member 41 over the entire circumferential direction of the rubber plate 44. Specifically, the inner peripheral portion of the rubber plate 44 is fixed to the fixing member 41 by the flange portion 59 a of the second fixing member 59, the first fixing member 58, and the retaining ring 51. The flange portion 59a is disposed below the lower surface of the first fixing member 58, and the inner peripheral side portion of the rubber plate 44 is sandwiched between the upper surface of the flange portion 59a and the lower surface of the first fixing member 58. ing. The retaining ring 51 is attached to the upper end portion of the second fixing member 59 and functions to prevent the second fixing member 59 from coming off from the first fixing member 58.

  The outer diameter of the flange portion 59a of the second fixing member 59 is smaller than the inner diameter of the concave portion 49a of the second holding member 49, and the flange portion 59a is disposed in the concave portion 49a. The lower end portion 58 b of the second fixing member 58 is disposed in the through hole 48 a of the first holding member 48. A gap is formed between the outer peripheral surface of the lower end portion 58b and the inner peripheral surface of the through hole 48a.

  In a state where no external force is applied to the suction plate 40, the center of the suction hole 41d of the fixing member 41 and the center of the suction hole 49b of the second holding member 49 (specifically, the suction hole when viewed from above and below). 49b and the center of the portion recessed downward from the bottom surface of the recess 49a. The upper end portion of the compression coil spring 45 is disposed in the suction hole 41d, and the lower end portion of the compression coil spring 45 is disposed in the suction hole 49b. The upper end of the compression coil spring 45 is in contact with the step surface formed on the upper end side of the suction hole 41d, and the lower end of the compression coil spring 45 is in contact with the bottom surface of the suction hole 49b.

  A portion surrounded by the suction portion 39, the holding member 43, and the rubber plate 44 is a sealed space S to which the suction holes 40a, 41d, and 49b are connected. Specifically, a portion surrounded by the flange portion 59 a of the second fixing member 59, the second holding member 49, and the rubber plate 44 is a sealed space S. That is, the space inside the recess 49a and below the rubber plate 44 and outside the flange 59a is a sealed space S.

  In this embodiment, when air is sucked by the suction mechanism connected to the suction hole 49b in a state where the conveyance object 2 is placed on the suction plate 40, the suction hole 49b, the sealed space S, the suction hole 41d, the concave portion The conveyance object 2 is sucked through the suction holes 40a and the suction holes 40a, and the conveyance object 2 is sucked by the suction plate 40. Further, when the conveyance object 2 is adsorbed to the adsorption plate 40, the sealed space S becomes negative pressure. When the sealed space S becomes negative pressure, the suction portion 39 moves downward against the urging force of the compression coil spring 45 as shown in FIG. At this time, the rubber plate 44 is deformed.

(Arrangement of adsorption mechanism)
FIG. 8 is a diagram for explaining a reference for arranging the plurality of suction mechanisms 22 shown in FIG. 3.

  As described above, in the fork 18, the suction mechanism 22 is attached to two positions on the front end side of the fork 18. In the fork 19, the suction mechanism 22 includes two positions on the front end side of the fork 19 and the fork 19 in the front-rear direction. It is attached to a total of three places including one of the intermediate positions. That is, two suction mechanisms 22 are attached to the two forks 18, and three suction mechanisms 22 are attached to the two forks 19.

  In the following description, when a plurality of suction mechanisms 22 attached to the forks 18 and 19 are distinguished from each other, as shown in FIG. 3, the suction located at the most distal end side of the four forks 18 and 19 is used. The mechanism 22 is the suction mechanism 22A, and the suction mechanism 22 disposed second from the tip of the four forks 18 and 19 is the suction mechanism 22B. The suction mechanism 22 arranged third from the tip of the fork 19 is referred to as a suction mechanism 22C. That is, the suction mechanism 22 except the suction mechanisms 22A and 22B attached to the fork 19 is referred to as a suction mechanism 22C. The adsorption mechanism 22A of this embodiment is a first adsorption mechanism, the adsorption mechanism 22B is a second adsorption mechanism, and the adsorption mechanism 22C is a third adsorption mechanism.

  The four suction mechanisms 22A attached to the four forks 18 and 19 are arranged at the same position in the front-rear direction. Further, the four suction mechanisms 22B attached to the four forks 18 and 19 are arranged at the same position in the front-rear direction. Further, the two suction mechanisms 22C attached to the two forks 19 are arranged at the same position in the front-rear direction. The distance between the suction mechanism 22A and the suction mechanism 22B in the front-rear direction is shorter than the distance between the suction mechanism 22B and the suction mechanism 22C in the front-rear direction.

  In this embodiment, when the suction mechanism 22 is attached to the two forks 18 and the two forks 19 at the same position in the front-rear direction, the air suction path of the suction mechanism 22 attached to the two forks 18 and the two forks An air suction path of the suction mechanism 22 attached to the fork 19 is common. That is, the air suction paths of the four suction mechanisms 22A are common, and the air suction paths of the four suction mechanisms 22B are common.

  In this embodiment, the air suction paths of the four suction mechanisms 22A and the air suction paths of the four suction mechanisms 22B are a common suction path (first suction path). Specifically, the four suction mechanisms 22A and the four suction mechanisms 22B are connected to the above suction mechanism via a common electromagnetic valve (not shown). The air suction paths of the two suction mechanisms 22C are common. Also, the air suction paths of the two suction mechanisms 22C are different from the air suction paths (first suction paths) of the four suction mechanisms 22A and the four suction mechanisms 22B, and the suction paths (second suction paths). It has become. Specifically, the two adsorption mechanisms 22C are connected to the above-described suction mechanism via a common electromagnetic valve (not shown).

  In the present embodiment, when a relatively small conveyance object 2 is mounted on the hand 3, the four adsorption mechanisms 22A and the four adsorption mechanisms 22B adsorb the conveyance object 2. When the relatively large transport object 2 is mounted on the hand 3, the four suction mechanisms 22A, the four suction mechanisms 22B, and the two suction mechanisms 22C suck the transport object 2.

  The height of the upper surface of the forks 18 and 19 where the suction mechanism 22A is attached is defined as a reference height, and the suction portion 39 holds the transport object 2 in the most inclined state in design with respect to the upper surfaces of the forks 18 and 19. When adsorbed (for example, when the adsorbing unit 39 adsorbs the conveyance object 2 accommodated in the cassette in the most bent state by design), the adsorbing unit 39 moves up and down with respect to the floating mechanism 42. Assuming that the possible amount is the maximum movable amount M (see FIG. 8), in the front-rear direction, the four suction mechanisms 22B have a difference in height of the upper surfaces of the forks 18 and 19 with respect to the reference height as the maximum movable amount M or less. It is arranged in the area. Further, the two suction mechanisms 22C are arranged in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M.

  That is, the suction mechanism 22B is attached to the two forks 18 and the two forks 19 in a region where the difference in height between the upper surfaces of the forks 18 and 19 with respect to the reference height in the front-rear direction is equal to or less than the maximum movable amount M. Yes. Further, in the front-rear direction, the suction mechanism 22C is attached only to the two forks 19 in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M. The maximum movable amount M of the present embodiment is such that the suction portion 39 moves up and down with respect to the holding member 43 when the suction portion 39 sucks the conveyance object 2 that is most inclined in design with respect to the upper surfaces of the forks 18 and 19. The amount that can move in the direction.

  In addition, the amount (floating amount) that the suction portion 39 can move in the vertical direction with respect to the holding member 43 when no external force is applied to the suction portion 39 is, for example, 1 (mm), and the front-rear direction The distance between the adsorption mechanism 22A and the adsorption mechanism 22B is, for example, 400 (mm). Further, the height difference of the upper surface of the forks 18 and 19 where the suction mechanism 22B is attached to the reference height is, for example, 0.5 (mm) or less. The height difference with respect to the reference height of the portion to which the suction mechanism 22C is attached exceeds, for example, 0.5 (mm).

  That is, in the region where the difference in height of the upper surfaces of the forks 18 and 19 with respect to the reference height in the front-rear direction is 0.5 (mm) or less, for example, the suction mechanism 22B is attached to the two forks 18 and the two forks 19. In the region where the height difference of the upper surface of the forks 18 and 19 with respect to the reference height exceeds 0.5 (mm) in the front-rear direction, for example, the suction mechanism 22C is attached only to the two forks 19. Yes.

(Main effects of this form)
As described above, in this embodiment, the air suction paths of the four suction mechanisms 22A are common, and the air suction paths of the four suction mechanisms 22B are common. Therefore, in this embodiment, it is possible to simplify the air suction path of the suction mechanisms 22A and 22B attached to the four forks 18 and 19. In particular, in this embodiment, the air suction paths of the four suction mechanisms 22A and the air suction paths of the four suction mechanisms 22B are common, so that the suction mechanisms 22A attached to the four forks 18 and 19 are used. , 22B air suction path can be further simplified.

  In the present embodiment, the suction mechanism 22B is attached to the two forks 18 and the two forks 19 in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height is not more than the maximum movable amount M in the front-rear direction. However, in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M in the front-rear direction, the suction mechanism 22C is attached to only the two forks 19. Therefore, in this embodiment, when a relatively large transport object 2 is transported and the transport object 2 is difficult to bend between the adjacent forks 18 and 19 (specifically, Even when the conveyance object 2 has a relatively high rigidity and the distance between the adjacent forks 18 and 19 is close), all the adsorption mechanisms 22 (that is, ten adsorption mechanisms 22) are conveyed. The conveyance object 2 can be adsorbed by all the adsorption mechanisms 22 in contact with the object 2.

  Further, in this embodiment, in the front-rear direction, the suction mechanism 22C is attached to only the two forks 19 in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M. Therefore, when the suction mechanism 22C is attached only to the two forks 18 arranged on the inner side in the left-right direction in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M. Compared to the above, it is possible to widen the interval between the suction mechanisms 22C in the left-right direction. Therefore, in this embodiment, it is possible to stabilize the state of the conveyance target object 2 adsorbed by the adsorption mechanism 22C.

  Further, when the suction mechanism 22C is attached only to the two forks 18 in a region where the difference in height between the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M in the front-rear direction, When the fork 18 is in close contact, the suction mechanism 22C of one of the two forks 18 may not be brought into contact with the object 2 to be conveyed, but in this embodiment, the two forks 18 Even when the two come into close contact, the suction mechanism 22C of the two forks 19 can be brought into contact with the conveyance object 2.

  In this embodiment, when the conveyance object 2 is attracted to the suction plate 40, the sealed space S becomes negative pressure, and the suction portion 39 moves downward against the urging force of the compression coil spring 45. For this reason, in this embodiment, after the suction plate 40 sucks the conveyance object 2 and the suction portion 39 moves downward, the suction portion 39 is less likely to wobble with respect to the forks 18 and 19. Therefore, in this embodiment, it is possible to stabilize the state of the conveyance object 2 mounted on the hand 3 when the conveyance object 2 is conveyed.

(Other embodiments)
The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited to this, and various modifications can be made without departing from the scope of the present invention.

  In the embodiment described above, the suction mechanism 22B may not be attached to the forks 18 and 19. That is, the number of suction mechanisms 22 attached to the fork 18 may be one, and the number of suction mechanisms 22 attached to the fork 19 may be two. The number of suction mechanisms 22 attached to the fork 18 may be three or more, and the number of suction mechanisms 22 attached to the fork 19 may be four or more. Even in this case, in the front-rear direction, in the region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height is equal to or less than the maximum movable amount M, the two forks 18 and the two forks 19 are attached to the suction mechanism. In the region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M in the front-rear direction, the suction mechanism 22 is attached only to the two forks 19.

  In the embodiment described above, the air suction paths of the four suction mechanisms 22A and the air suction paths of the four suction mechanisms 22B are common, but the air suction paths of the four suction mechanisms 22A and the four The air suction paths of the individual suction mechanisms 22B may be provided individually. Further, in the embodiment described above, the suction mechanism 22 may be attached to only the two forks 18 in a region where the height difference of the upper surfaces of the forks 18 and 19 with respect to the reference height exceeds the maximum movable amount M.

  In the embodiment described above, the height of the upper surface of the forks 18 and 19 where the suction mechanism 22A is attached is the reference height, but the suction mechanism 22B of the upper surface of the forks 18 and 19 is attached. The height of the part may be the reference height. In this case, the suction mechanism 22B becomes the first suction mechanism. In the embodiment described above, the biasing member that biases the suction portion 39 upward with respect to the holding member 43 may be a spring member such as a leaf spring.

  In the embodiment described above, the pitch of the two forks 18 in the left-right direction may be fixed, or the pitch of the two forks 19 in the left-right direction may be fixed. In the above-described embodiment, the robot 1 is a horizontal articulated robot, but the robot to which the present invention is applied may be an industrial robot other than the horizontal articulated robot. For example, the robot to which the present invention is applied may be an industrial robot disclosed in Patent Document 1 described above.

1 Robot (industrial robot)
2 Object to be transported 3 Hand 4 Arm 5 Body 18 Fork (inner fork)
19 Fork (outside fork)
22 Adsorption mechanism 22A Adsorption mechanism (first adsorption mechanism)
22B Adsorption mechanism (second adsorption mechanism)
22C adsorption mechanism (third adsorption mechanism)
39 Suction part 40a, 41d Suction hole 42 Floating mechanism 43 Holding member 44 Rubber plate 45 Compression coil spring (biasing member)
49b Suction hole (second suction hole)
M Maximum movable amount S Sealed space X Fork longitudinal direction Y Orthogonal direction

Claims (6)

In industrial robot hands that transport objects to be transported,
Four forks that are linearly formed and arranged in parallel with each other, and a plurality of suction mechanisms that vacuum-suck the lower surface of the object to be transported placed on the upper surface side of the fork,
The suction mechanism includes a suction portion that sucks the conveyance object, and a floating mechanism that supports the suction portion so as to be tiltable and vertically movable with respect to the fork.
On the tip side of the four forks, a first suction mechanism as the suction mechanism is attached at the same position in the longitudinal direction of the fork,
A direction orthogonal to the longitudinal direction and the vertical direction of the fork is an orthogonal direction, and each of the two forks arranged inside the orthogonal direction among the four forks is an inner fork, and the orthogonal direction When each of the remaining two forks arranged outside the outer fork is an outer fork,
When the suction mechanism is attached to the two inner forks and the two outer forks at the same position in the longitudinal direction of the fork, the air suction path of the suction mechanism attached to the two inner forks And an air suction path of the suction mechanism attached to the two outer forks are common.
The height of the upper surface of the fork on which the first suction mechanism is attached is defined as a reference height, and the suction unit sucks the conveyance object in the most inclined design with respect to the upper surface of the fork. When the amount by which the suction part can move up and down with respect to the floating mechanism is the maximum movable amount,
In the region where the height difference of the upper surface of the fork with respect to the reference height is less than or equal to the maximum movable amount in the longitudinal direction of the fork, the suction mechanism is attached to the two inner forks and the two outer forks. And
In the longitudinal direction of the fork, in the region where the height difference of the upper surface of the fork with respect to the reference height exceeds the maximum movable amount, only the two inner forks or only the two outer forks are the suction mechanism. A hand characterized in that is attached. The floating mechanism includes a holding member that is fixed to the fork and holds the suction portion so as to be tiltable and vertically movable, and a biasing member that biases the suction portion upward with respect to the holding member. An annular rubber plate that connects the adsorbing portion and the holding member;
The outer peripheral side portion of the rubber plate is fixed to the holding member over the entire circumferential direction of the rubber plate,
The inner peripheral side portion of the rubber plate is fixed to the suction portion over the entire circumferential direction of the rubber plate,
The maximum movable amount is such that the suction portion can move in the vertical direction with respect to the holding member when the suction portion sucks the conveyance object that is most inclined in design with respect to the upper surface of the fork. The hand according to claim 1, wherein the hand is a quantity. The suction part is formed with a suction hole for sucking the conveyance object to the suction part,
A portion surrounded by the suction portion, the holding member, and the rubber plate is a sealed space to which the suction hole is connected,
The holding member has a second suction hole connected to the sealed space,
When air is sucked by the suction mechanism connected to the second suction hole and the conveyance object is sucked to the suction portion, the sealed space becomes negative pressure and resists the biasing force of the biasing member. The hand according to claim 2, wherein the suction portion moves downward.   In the longitudinal direction of the fork, in the region where the height difference of the upper surface of the fork with respect to the reference height exceeds the maximum movable amount, the suction mechanism is attached only to the two outer forks. The hand according to any one of claims 1 to 3. Two of the suction mechanisms including the first suction mechanism are attached to the two inner forks,
Three of the suction mechanisms including the first suction mechanism are attached to the two outer forks,
The first suction mechanism is disposed on the most distal end side of the four forks,
The second adsorption mechanism as the adsorption mechanism arranged second from the front ends of the four forks is arranged at the same position in the longitudinal direction of the forks,
When the suction mechanism excluding the first suction mechanism and the second suction mechanism attached to the outer fork is a third suction mechanism,
The four air suction paths of the first suction mechanism and the four air suction paths of the second suction mechanism are common first suction paths,
5. The hand according to claim 4, wherein the air suction path of the two third suction mechanisms is a second suction path different from the first suction path.   A hand according to any one of claims 1 to 5, an arm to which the hand is rotatably connected to a distal end side, and a main body portion to which a proximal end side of the arm is rotatably connected. A featured industrial robot.

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