KR102060245B1 - Hand of industrial robot and industrial robot - Google Patents

Abstract

Even if the amount of change of the pitch of a plurality of forks is relatively large, an industrial robot hand capable of smoothly changing the pitch of a plurality of forks can be provided while reducing the cost of a motor which is a driving source of the fork pitch changing mechanism.
This hand includes fork pitch changing mechanisms 26 and 27 for changing the pitches of a plurality of forks in the Y direction orthogonal to the long side direction of the fork and the vertical direction, and a guide mechanism 50 for guiding the fork in the Y direction. ). The fork pitch changing mechanisms 26 and 27 include the motors 29 and 34, screw members 30 and 35 connected to the output shafts of the motors 29 and 34, while trapezoidal screws or angle screws are formed on the outer circumferential surface thereof, Nut members 32 and 37 engaged with the screw members 30 and 35, and slide members 31 and 36 fixed to the fork are provided. The nut members 32 and 37 are held by the slide members 31 and 36 so that movement in the direction orthogonal to a Y direction is attained.

Description

HAND OF INDUSTRIAL ROBOT AND INDUSTRIAL ROBOT}

The present invention relates to a hand of an industrial robot for conveying an object to be conveyed. Moreover, this invention relates to the industrial robot provided with this hand.

Conventionally, the industrial robot which conveys the glass substrate for liquid crystal displays is known (for example, refer patent document 1). The hand of the industrial robot of patent document 1 is provided with two forks formed in linear form, and the fork pitch change mechanism which changes the pitch of two forks in the direction orthogonal to the long side direction of a fork, and a vertical direction. The fork pitch change mechanism includes a motor serving as a drive source, a screw member connected to an output shaft of the motor, a nut member fixed to one of the two forks, and a nut member fixed to the other fork.

Japanese Patent Laid-Open No. 2017-19061

MEANS TO SOLVE THE PROBLEM This inventor is considering the adoption of a comparatively inexpensive DC motor as a motor which is a drive source of a fork pitch change mechanism in order to reduce the cost of the hand which has a fork pitch change mechanism. However, in the case where the drive source of the fork pitch change mechanism is a DC motor, if the external force in the direction (orthogonal direction) orthogonal to the long side direction of the fork and the up-down direction is applied to the fork while the DC motor is powered off, There is a risk of shifting in the orthogonal direction. Therefore, the inventors of the present invention provide a screw member connected to the output shaft of the motor so that the fork does not shift in the orthogonal direction even if the external force in the orthogonal direction acts on the fork while the power supply of the DC motor is cut off, and a trapezoidal screw or an angular screw is formed on the outer circumferential surface thereof. The adoption of the screw member to be used is considered.

On the other hand, in recent years, there is a demand for conveying many kinds of conveying objects having different widths in the orthogonal direction by a common hand. In order to comply with these requirements, it is necessary to increase the amount of change of the pitch of two forks, and to lengthen the amount of change of the pitch of two forks, it is necessary to lengthen the length of a screw member. However, when the length of a screw member becomes long, there exists a possibility that the straightness (linearity) of a screw member may fall. Moreover, when the linearity of the screw member in which a trapezoidal screw or a square thread is formed in the outer peripheral surface falls, the contact resistance of a screw member and a nut member at the time of rotation of a screw member will become large, As a result, the torque for rotating a screw member will become large. There is a possibility that the screw member cannot be rotated.

That is, when the straightness of the screw member in which the trapezoidal screw or the angular thread is formed in the outer peripheral surface falls, it becomes impossible to rotate a screw member, and there exists a possibility that the pitch of two forks may not be changed smoothly. In addition, if a large capacity DC motor is employed as the driving source of the fork pitch changing mechanism, it is possible to rotate the screw member even if the torque for rotating the screw member becomes large, but in this case, the cost of the DC motor becomes high.

Therefore, the subject of this invention is the hand of the industrial robot provided with the fork pitch change mechanism which changes the pitch of a some fork, WHEREIN: Even if the amount of change of the pitch of a plurality of forks is comparatively large, The present invention provides a hand of an industrial robot capable of smoothly changing the pitch of a plurality of forks while reducing costs. Moreover, the subject of this invention is providing the industrial robot provided with this hand.

In order to solve the said subject, the hand of the industrial robot of this invention is a perpendicular | vertical orthogonal orthogonal to the long side direction and the up-down direction of the several forks formed linearly in the hand of the industrial robot which conveys a conveyed object, and a fork. And a fork pitch changing mechanism for changing the pitch of the plurality of forks in the direction, and a guide mechanism for guiding the fork in the orthogonal direction. The fork pitch changing mechanism includes a motor serving as a drive source and a trapezoidal screw or a square screw on the outer circumferential surface thereof. And a screw member connected to the output shaft of the motor, a nut member engaged with the screw member, and a slide member fixed to the proximal end of the fork. The nut member has a movement in a direction perpendicular to the orthogonal direction. It is hold | maintained by the slide member so that it may become possible.

In the hand of the industrial robot of the present invention, a trapezoidal screw or an angular screw is formed on the outer circumferential surface of the screw member connected to the output shaft of the motor. Therefore, in the present invention, even when a relatively inexpensive DC motor is used as the motor, it is possible to prevent the fork from shifting in the orthogonal direction when an external force in the orthogonal direction acts on the fork while the motor is powered off.

Moreover, in this invention, the nut member engaging by the screw member is hold | maintained by the slide member so that the movement to the direction orthogonal to a orthogonal direction becomes possible. That is, in the present invention, the nut member can move in a direction orthogonal to the orthogonal direction with respect to the slide member fixed to the fork guided in the orthogonal direction by the guide mechanism. Therefore, in this invention, the length of a screw member becomes long in order to enlarge the change amount of the pitch of several forks, As a result, even if the straightness of a screw member falls, when a screw member rotates, It is possible to reduce the contact resistance. Therefore, in this invention, even if the length of a screw member becomes long and the linearity of a screw member falls, even if the cheap motor with a small capacity is used, it becomes possible to rotate a screw member and to change the pitch of several forks smoothly. . That is, in the present invention, even if the amount of change of the pitches of the plurality of forks is relatively large, the pitches of the plurality of forks can be smoothly changed while reducing the cost of the motor which is the driving source of the fork pitch changing mechanism.

In the present invention, for example, the fork pitch change mechanism includes a bolt for attaching a nut member to a slide member, and a cylindrical member having a cylindrical shape and a cylindrical portion through which a bolt is inserted at an inner circumferential side thereof. The round hole-shaped arrangement hole in which a cylindrical part is arrange | positioned is formed so that the nut member may penetrate in a orthogonal direction, The screw member in which the front-end | tip part of a bolt is screwed is formed in the slide member, and the inner diameter of a placement hole is the outer diameter of a cylindrical part. It is larger and the thickness of the nut member in the orthogonal direction is thinner than the length of the cylindrical part in the orthogonal direction. In this case, it becomes possible to hold the nut member to the slide member so that movement in the direction orthogonal to the orthogonal direction is possible with a comparatively simple structure.

In the present invention, the nut member is formed such that an insertion through hole through which the screw member is inserted penetrates the nut member in the orthogonal direction, and is engaged with a trapezoidal screw or an angular screw to a part of the insertion through hole in the orthogonal direction. It is preferable that a female screw is formed. In this case, for example, the length in the orthogonal direction of the female threaded portion where the female thread is formed is approximately 1.5 times the pitch of the trapezoidal screw or the square thread. This configuration makes it possible to shorten the engagement length of the screw member and the nut member. Therefore, even if the nut member is inclined with respect to the screw member, it is possible to reduce the contact resistance between the screw member and the nut member when the screw member rotates. Therefore, the capacity of the motor can be further reduced.

In the present invention, the fork pitch changing mechanism changes the pitch of the two forks, and the screw member connects the forward screw portion in which the forward screw is formed, the reverse screw portion in which the reverse thread is formed, and the forward screw portion and the reverse screw portion. The nut member held by the slide member fixed to one fork of two forks is coupled to the forward screw part, and the slide member fixed to the other fork of two forks to the reverse thread part. It is preferable that the nut member held in the latch is engaged. In this configuration, since the forward screw portion and the reverse screw portion formed separately are connected by coupling, the length of the integrally formed portion of the screw member as compared with the case where the forward screw portion and the reverse screw portion are integrally formed. It becomes possible to shorten. Therefore, it becomes possible to suppress the fall of the linearity of a screw member.

The hand of this invention can be used for the industrial robot which has an arm with which a hand is rotatably connected to the front end side, and the main body part with which the base end side of the arm is rotatably connected. In this industrial robot, even if the pitch change amount of the plurality of forks is relatively large, the pitches of the plurality of forks can be smoothly changed while reducing the cost of the motor which is the driving source of the fork pitch changing mechanism.

As described above, in the present invention, even if the amount of change in the pitch of the plurality of forks is relatively large, the pitch of the plurality of forks can be smoothly changed while reducing the cost of the motor which is the driving source of the fork pitch changing mechanism.

1 is a plan view of an industrial robot according to an embodiment of the present invention.
FIG. 2 is a side view of the industrial robot shown in FIG. 1.
FIG. 3 is a plan view for explaining the structure of the inside of the base of the hand shown in FIG. 1.
4 is a plan view for explaining the operation of the fork shown in FIG.
It is a top view for demonstrating the structure of the fork pitch change mechanism in E part of FIG.
It is a top view for demonstrating the structure of the fork pitch change mechanism in F part of FIG.
It is a side view for demonstrating the structure of the fork pitch change mechanism from the GG direction of FIG.
FIG. 8A is an enlarged view of a portion H of FIG. 5, and FIG. 8B is an enlarged view of a portion J of FIG. 5.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described, referring drawings.

(Overall Configuration of Industrial Robots)

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. 1.

The industrial robot 1 (henceforth "robot 1") of this form is a horizontal articulated robot for conveying the predetermined conveying object 2. The conveyed object 2 is a glass substrate for liquid crystal displays, for example. This conveyance object 2 is formed in rectangular flat plate shape. The robot 1 of this embodiment can carry many kinds of conveyed objects 2 of different sizes.

The robot 1 comprises two hands 3 on which the conveyed object 2 is mounted, two arms 4 each of which the two hands 3 are connected to the distal end side, and two arms 4. The main body 5 to support and the base 6 which support the main body 5 to be movable in a horizontal direction are provided. The main body part 5 supports the base end side of the arm 4, and the arm support 7 which can move up and down, the support frame 8 which supports the arm support 7 so that it can move up and down, and a main body part A base 9 that is horizontally movable with respect to the base 6 and the bottom frame of the supporting frame 8 is fixed while the lower part of the base 5 is rotated, and the pivot frame 10 that can be rotated with respect to the base 9 is provided. Equipped with.

The arm 4 is comprised by the two arm parts of the 1st arm part 12 and the 2nd arm part 13. As shown in FIG. The base end side of the 1st arm part 12 is connected to the arm support 7 so that rotation is possible. That is, the base end side of the arm 4 is connected to the main body part 5 so that rotation is possible. The proximal end 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 front end side of the second arm portion 13. That is, the hand 3 is rotatably connected to the front end side of the arm 4. The robot 1 is equipped with two arm drive mechanisms which expand and contract each of the two arms 4.

The support frame 8 supports the hand 3 and the arm 4 to be lifted and lowered through the arm support 7. The support frame 8 is formed of a columnar first support frame 14 for holding the arm support 7 in a liftable manner and a columnar agent for holding the first support frame 14 in a liftable manner. 2 supporting frames 15 are provided. The robot 1 includes an elevating mechanism for elevating the arm support 7 with respect to the first supporting frame 14, an elevating mechanism for elevating the first supporting frame 14 with respect to the second supporting frame 15, and A guide mechanism for guiding the first support frame 14 in the vertical direction and a guide mechanism for guiding the arm support 7 in the vertical direction are provided.

The lower end of the second support frame 15 is fixed to the swing frame 10. As described above, the swing frame 10 is rotatable with respect to the base 9. The robot 1 is provided with the rotation mechanism which rotates the revolving frame 10 with respect to the base 9. The base 9 is movable horizontally with respect to the base 6 as mentioned above. The robot 1 is provided with the horizontal movement mechanism which horizontally moves the base 9 with respect to the base 6.

(Configuration of the hand)

FIG. 3 is a plan view for explaining the internal structure of the base 17 of the hand 3 shown in FIG. 1. FIG. 4 is a plan view for explaining the operation of the forks 18 and 19 shown in FIG.

The hand 3 is provided with the base 17 connected rotatably to the front end side of the 2nd arm part 13, and the several forks 18 and 19 by which the conveying object 2 is mounted on the upper surface side, have. The hand 3 of this embodiment is provided with four forks 18 and 19 in total of 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 the several loading member (not shown) in which the conveying object 2 is mounted, and the conveying object 2 mounted in this loading member is carried out. A plurality of adsorption mechanisms (not shown) are provided for vacuum adsorption of the lower surface.

The base 17 is formed in a hollow substantially rectangular parallelepiped shape with a hollow shape and a thin thickness in the vertical direction. The forks 18 and 19 are formed linearly. Four forks 18 and 19 protrude from the base 17 in the same direction in the horizontal direction. In addition, the four forks 18 and 19 are arrange | positioned in parallel with each other. When the long side directions (X directions as shown in Fig. 3) of the forks 18 and 19 are set to the "front and rear direction", and the Y direction of FIG. 18 is arrange | positioned inside a left-right direction, and the two forks 19 are arrange | positioned at the outer side of a left-right direction. The left-right direction (Y direction) of this form is the orthogonal direction orthogonal to the long side direction of the forks 18 and 19, and an up-down direction.

The forks 18 and 19 are formed of resin containing carbon fiber. In addition, the forks 18 and 19 are formed in hollow shape, and are formed in the elongate substantially rectangular parallelepiped shape. The upper and lower surfaces of the forks 18 and 19 are planar. In addition, the left and right side surfaces of the forks 18 and 19 are planes orthogonal to the left and right directions. The thickness in the up-down direction of the forks 18 and 19 is gradually thinner from the base end of the forks 18 and 19 toward the tip (see Fig. 2).

The proximal ends of the forks 18 and 19 are arranged inside the base 17 formed in a hollow shape. As shown in FIG. 3, inside the base 17, the fork pitch change mechanism 26 which changes the pitch of the two forks 18 in the left-right direction, and the two forks 19 in the left-right direction. The fork pitch change mechanism 27 which changes the pitch of () is arrange | positioned. That is, the hand 3 is provided with the fork pitch change mechanism 26,27.

In the fork pitch changing mechanism 26, one of the forks 18 and the other fork 18 of the two forks 18 are moved by the same amount in the reverse direction from the left and right to the left and right directions of the two forks 18. The pitch is changed. Similarly, in the fork pitch changing mechanism 27, one fork 19 and the other fork 19 of the two forks 19 move by the same amount in the opposite directions from the left and right to the left and right sides of the two forks 19. The pitch of the direction is changed.

In this embodiment, when the size of the conveyed object 2 conveyed by the robot 1 is determined, the fork pitch change mechanism 26 is necessary before the conveyance operation | movement which the robot 1 conveys the conveyed object 2 is required. As a result, the pitches in the left and right directions of the two forks 18 are changed, and the fork pitch changing mechanism 27 changes the pitch in the left and right directions of the two forks 19 as necessary. That is, the fork pitch change mechanisms 26 and 27 do not change the pitch in the left-right direction of the forks 18 and 19 during the conveyance operation | movement of the conveying object 2 by the robot 1. Fork pitch change mechanisms 26 and 27 are pitches in the left and right directions of the forks 18 and 19 according to the size of the conveyed object 2 conveyed to the robot 1, for example, as shown in FIG. 4. Change The detailed structure of the fork pitch change mechanisms 26 and 27 is mentioned later.

Moreover, inside the base 17, the detection mechanism 21 for detecting the fork 18 from the inner end side of the left-right direction in the moving range of the two forks 18, and the two forks 19 A detection mechanism 22 for detecting the fork 19 on the outside end side in the left and right direction in the movement range, and a detection mechanism for detecting that the fork 18 and the fork 19 adjacent to each other in the left and right directions are approached ( 23) is arranged. That is, the hand 3 is provided with the detection mechanisms 21-23.

The detection mechanism 21 includes a sensor 56 fixed to the base frame 55 of the base 17 and a detection plate 57 fixed to the proximal end of one fork 18 of the two forks 18. Equipped. The detection mechanism 22 is provided with the sensor 58 fixed to the base frame 55, and the detection plate 59 fixed to the base end part of one fork 19 among two forks 19. As shown in FIG. The sensors 56 and 58 are transmission type optical sensors which have a light emitting element and a light receiving element. In this embodiment, the origin position of the two forks 18 is detected using the detection mechanism 21. In addition, the home position of the two forks 19 is detected using the detection mechanism 22.

The detection mechanism 23 is fixed to the sensor 60 fixed to the proximal end of the other fork 19 of the two forks 19 and the proximal end of the other fork 18 of the two forks 18. The detection plate 61 to be provided is provided. The sensor 60 is a transmissive optical sensor having a light emitting element and a light receiving element. In addition, the sensor 62 is fixed to the base frame 55. The sensor 62 is a transmissive optical sensor having a light emitting element and a light receiving element. In this embodiment, the sensor 62 and the detection plate 59 detect a mechanism for detecting that the fork 19 is close to a limit position in the left and right directions in the moving range of the two forks 19 ( 24) is configured.

(Configuration of Fork Pitch Change Mechanism)

FIG. 5: is a top view for demonstrating the structure of the fork pitch change mechanism 26, 27 in the E part of FIG. FIG. 6: is a top view for demonstrating the structure of the fork pitch change mechanisms 26 and 27 in the F part of FIG. FIG. 7: is a side view for demonstrating the structure of the fork pitch change mechanism 26,27 from the G-G direction of FIG. FIG. 8A is an enlarged view of a portion H of FIG. 5, and FIG. 8B is an enlarged view of a portion J of FIG. 5.

The fork pitch change mechanism 26 includes a motor 29 as a drive source, a screw member 30 connected to an output shaft of the motor 29, and a proximal end side of one fork 18 of the two forks 18. Of the slide member 31 fixed to the base end), the slide member 31 fixed to the base end side (base end) of the other fork 18 of the two forks 18, and the two slide members 31. It is provided in each, and is provided with the two nut member 32 which engages with the screw member 30. As shown in FIG. Moreover, the fork pitch change mechanism 26 is provided with the encoder 33 which detects the rotation amount of the screw member 30. As shown in FIG.

The fork pitch change mechanism 27 is configured similarly to the fork pitch change mechanism 26. In other words, the fork pitch change mechanism 27 includes one of the motor 34 configured similarly to the motor 29, the screw member 35 configured similarly to the screw member 30, and the two forks 19. A slide member 36 fixed to the proximal end (base end) of the fork 19, a slide member 36 fixed to the proximal side (base end) of the other fork 19 of the two forks 19, It is provided with each of the two slide members 36, and is provided with the two nut members 37 which engage with the screw member 35, and the encoder 38 which detects the rotation amount of the screw member 35. As shown in FIG. .

Motors 29 and 34 are DC motors. The screw members 30 and 35 are formed in elongate rod shape. The screw members 30 and 35 are arrange | positioned so that the axial direction and the left-right direction of the screw members 30 and 35 may correspond, and rotate the left-right direction as an axial direction of rotation. In addition, the screw member 30 and the screw member 35 are arrange | positioned at the predetermined space | interval in the front-back direction. An output shaft of the motor 29 is connected to one end of the screw member 30 through a coupling 41, and an output shaft of the motor 34 is connected to one end of the screw member 35 through a coupling 41. It is.

The screw members 30 and 35 are forward screw parts 30a and 35a constituting one end side of the screw members 30 and 35 and reverse screw parts 30b and 35b constituting the other end side of the screw members 30 and 35. ). The forward screw is formed in the forward screw parts 30a and 35a, and the reverse thread is formed in the reverse thread parts 30b and 35b. The forward thread formed in the forward screw portions 30a and 35a and the reverse thread formed in the reverse thread portions 30b and 35b are trapezoidal screws. That is, trapezoidal screws are formed on the outer circumferential surfaces of the screw members 30 and 35.

The forward screw portion 30a and the reverse screw portion 30b are formed separately, and are connected by a coupling 42. Similarly, the forward screw part 35a and the reverse screw part 35b are formed separately, and are connected by the coupling 42. As shown in FIG. That is, the screw member 30 is provided with the coupling 42 which connects the forward screw part 30a and the reverse screw part 30b, and the screw member 35 connects the forward screw part 35a and the reverse screw part 35b. The coupling 42 which connects is provided. In this embodiment, the screw member 30 is comprised by the forward screw part 30a, the reverse screw part 30b, and the coupling 42, and is provided to the forward screw part 35a, the reverse screw part 35b, and the coupling 42. The screw member 35 is comprised by this. Both ends of the forward screw portions 30a and 35a and both ends of the reverse screw portions 30b and 35b are rotatably supported by a bearing 43 provided on the base frame 55. In addition, the forward screw parts 30a and 35a and the reverse screw parts 30b and 35b of this form are rolled screws formed by rolling.

The slide member 31 is formed in the rectangular parallelepiped shape. The slide member 36 is formed in the rectangular parallelepiped like the slide member 31. As shown in FIG. The slide member 36 is being fixed to the flat fixing member 44 as shown in FIG. The fixing member 44 is fixed to the proximal end of the fork 19. Similarly, the slide member 31 is fixed to the fixing member 44 fixed to the proximal end of the fork 18. That is, the slide member 31 is fixed to the base end of the fork 18 via the fixing member 44, and the slide member 36 is fixed to the base end of the fork 19 via the fixing member 44. .

The nut member 32 is formed in the rectangular parallelepiped shape. The nut member 37 is formed in a rectangular parallelepiped shape similarly to the nut member 32. The nut member 32 is attached to the slide member 31 by the two bolts 45, and the nut member 37 is attached to the slide member 36 by the two bolts 45. As shown in FIG. That is, the fork pitch change mechanisms 26 and 27 are provided with the bolts 45 for attaching the nut members 32 and 37 to the slide members 31 and 36.

In addition, the fork pitch change mechanisms 26 and 27 are provided with the cylindrical member 46 formed in the cylindrical shape with a flange. The fork pitch change mechanisms 26 and 27 are provided with the same number of cylindrical members 46 as the bolts 45. The cylindrical member 46 is formed in a cylindrical shape and has a cylindrical portion 46a through which the bolt 45 is inserted through the inner circumferential side (specifically, a shaft portion of the bolt 45 is inserted) and a cylindrical portion 46a. It consists of an annular flange part 46b which spreads in a flange shape from one end of () (refer FIG. 8).

The slide member 31 is provided with a cutout 31a for preventing interference with the screw member 30 and a cutout 31b for preventing interference with the screw member 35. Similarly, the slide member 36 is formed with a cutout 36a for preventing interference with the screw member 30 and a cutout 36b for preventing interference with the screw member 35. Moreover, as shown to FIG. 8A, the slide member 31 is provided with two screw holes 31c by which the front-end | tip part of the bolt 45 is screwed. The screw hole 31c is formed in one side surface of the slide member 31 in the left-right direction. Similarly, the slide member 36 is provided with two screw holes 36c into which the tip end of the bolt 45 is screwed, as shown to FIG. 8 (B). The screw hole 36c is formed in one side surface of the slide member 36 in the left-right direction.

As shown in FIG. 8A, the nut member 32 is formed with an insertion through hole 32a through which the screw member 30 is inserted. The insertion hole 32a has penetrated the nut member 32 in the left-right direction. In addition, the insertion through hole 32a is formed in the center of the nut member 32. A part of the insertion hole 32a in the left-right direction is formed with a female screw engaged with the trapezoidal screw of the screw member 30. That is, the female screw is not formed in the whole region of the insertion through-hole 32a in the left-right direction. In this embodiment, the length of the left-right direction of the female screw part 32b in which a female screw is formed becomes about 1.5 times the pitch of the trapezoidal screw of the screw member 30. As shown in FIG.

Similarly to the nut member 32, the nut member 37 is provided with an insertion through hole 37a through which the screw member 35 is inserted (see FIG. 8B). Moreover, the female screw which engages with the trapezoidal screw of the screw member 35 is formed in one part of insertion hole 37a in the left-right direction. The length of the left-right direction of the female screw part 37b in which a female screw is formed becomes about 1.5 times the pitch of the trapezoidal screw of the screw member 35. FIG.

In addition, the nut member 32 is provided with a round hole arrangement hole 32c in which the cylindrical portion 46a is disposed. The placement hole 32c penetrates the nut member 32 in the left-right direction. Moreover, the arrangement | positioning hole 32c is formed in two places on both sides of the insertion through-hole 32a in the front-back direction. Similar to the nut member 32, the nut member 37 is provided with a round hole-shaped arrangement hole 37c in which the cylindrical portion 46a is disposed. The arranging holes 37c penetrate the nut member 37 in the left and right direction, and are formed at two positions on both sides of the insertion through hole 37a in the front-rear direction.

The inner diameter of the arranging holes 32c and 37c is larger than the outer diameter of the cylindrical part 46a, and the clearance gap is formed between the inner peripheral surface of the arranging holes 32c and 37c and the outer peripheral surface of the cylindrical part 46a. The outer diameter of the flange portion 46b is larger than the inner diameters of the placement holes 32c and 37c. In addition, the thickness (thickness in the left-right direction) of the nut members 32, 37 is slightly thinner than the length (length in the left-right direction) of the cylindrical portion 46a, and the nut members 32, 37 in the left-right direction. And at least one of the gap between the flange portion 46b and the nut members 32 and 37 and the slide members 31 and 36 are formed. In addition, the inner diameter of the cylindrical portion 46a is slightly larger than the outer diameter of the shaft portion of the bolt 45.

The nut member 32 is attached to the slide member 31 by the bolt 45 which penetrates into the inner peripheral side of the cylindrical part 46a from one side of the left-right direction, and is screwed into the screw hole 31c. . As described above, a gap is formed between the inner circumferential surface of the mounting hole 32c and the outer circumferential surface of the cylindrical portion 46a, and between the nut member 32 and the flange portion 46b or the nut member 32 in the horizontal direction. Since a small gap is formed between the slide member 31 and the nut member 32, the nut member 32 is movable in a direction perpendicular to the left and right directions with respect to the slide member 31. That is, the nut member 32 is hold | maintained by the slide member 31 so that a movement to the direction orthogonal to a left-right direction is possible. In addition, the nut member 32 is movable to the left-right direction with respect to the slide member 31 slightly.

Similarly, the nut member 37 is attached to the slide member 36 by a bolt 45 inserted into the inner circumferential side of the cylindrical portion 46a from one side in the left and right direction and screwed into the screw hole 36c. A gap is formed between the inner circumferential surface of the placement hole 37c and the outer circumferential surface of the cylindrical portion 46a, and between the nut member 37 and the flange portion 46b or between the nut member 37 and the slide in the horizontal direction. Since a slight gap is formed between the members 36, the nut member 37 is movable in a direction orthogonal to the left and right directions with respect to the slide member 36. That is, the nut member 37 is hold | maintained by the slide member 36 so that a movement to the direction orthogonal to a left-right direction is possible. In addition, the nut member 37 is movable to the left-right direction with respect to the slide member 36 slightly.

The nut member 32 held by the slide member 31 fixed to one fork 18 of the two forks 18 is engaged with the forward screw portion 30a, and to the other fork 18. The nut member 32 held by the fixed slide member 31 is engaged with the reverse screw portion 30b. Similarly, the nut member 37 held by the slide member 36 fixed to one fork 19 of the two forks 19 is engaged with the forward screw portion 35a and the other fork 19 The nut member 37 held by the slide member 36 fixed to the) is engaged with the reverse screw portion 35b.

Two forks 18 and two forks 19 are guided in left and right directions by two common guide rails 48. The guide rail 48 is being fixed to the base frame 55 so that the long side direction and the left-right direction of the guide rail 48 may correspond. In addition, one guide rail 48 of two guide rails 48 is arrange | positioned at the one end side of the base frame 55 in the front-back direction, and the other guide rail 48 is in the front-back direction. It is arrange | positioned at the other end side of the base frame 55 of the.

As shown in FIG. 7, two guide blocks 49 engaging with each of the two guide rails 48 are fixed to the fixing member 44 fixed to the proximal end of the fork 19. Similarly, two guide blocks 49 engaging with each of the two guide rails 48 are fixed to the fixing member 44 fixed to the proximal end of the fork 18. In this embodiment, the guide mechanism 50 which guides the forks 18 and 19 to the left-right direction is comprised by the two guide rails 48 and the two guide blocks 49. As shown in FIG.

In the fork pitch change mechanism 26, when the motor 29 rotates and the screw member 30 rotates, as described above, one fork 18 and the other fork 18 are the same in the right and left directions. Moving by the amount, the pitch in the left and right directions of the two forks 18 is changed. Similarly, in the fork pitch change mechanism 27, when the motor 34 rotates and the screw member 35 rotates, as described above, one fork 19 and the other fork 19 are reversed in left and right directions. By moving the same amount, the pitch in the left and right directions of the two forks 19 is changed.

The encoder 33 is provided with the detection plate 51 fixed to the other end part of the screw member 30, and the sensor 52 provided in the base frame 55. As shown in FIG. Similarly, the encoder 38 is provided with the detection plate 53 fixed to the other end of the screw member 35, and the sensor 54 provided in the base frame 55. As shown in FIG. The sensors 52 and 54 are transmissive optical sensors provided with a light emitting element and a light receiving element.

(Main effect of this form)

As described above, in this embodiment, a trapezoidal screw is formed on the outer circumferential surfaces of the screw members 30 and 35. Therefore, in this embodiment, even when the motors 29 and 34 are relatively inexpensive DC motors, the external force in the left and right directions acts on the forks 18 and 19 in a state in which the power of the motors 29 and 34 is cut off. It is possible to prevent misalignment of the forks 18 and 19 to the rollers.

In this embodiment, the nut member 32 is held by the slide member 31 fixed to the fork 18 guided in the left-right direction by the guide mechanism 50 so that movement in the direction orthogonal to the left-right direction is possible. Supported. Therefore, in this embodiment, the length of the screw member 30 becomes long in order to increase the amount of change of the pitch of the two forks 18, and as a result, even if the straightness of the screw member 30 falls, the screw member 30 ), It becomes possible to reduce the contact resistance between the screw member 30 and the nut member 32.

Similarly, in this embodiment, the nut member 37 can be moved in the direction orthogonal to the left and right directions to the slide member 36 fixed to the fork 19 guided in the left and right direction by the guide mechanism 50. Since it is held so that the length of the screw member 35 may become long in order to increase the change amount of the pitch of the two forks 19, as a result, even if the straightness of the screw member 35 falls, the screw member 35 ), It becomes possible to reduce the contact resistance between the screw member 35 and the nut member 37.

Therefore, in this embodiment, even if the length of the screw members 30 and 35 becomes long and the linearity of the screw members 30 and 35 falls, even if the cheap motors 29 and 34 with small capacity are used, the screw member 30 , 35 can be rotated to smoothly change the pitch of the forks 18 and 19. That is, in this embodiment, even if the pitch change amount of the forks 18 and 19 is relatively large, the pitches of the forks 18 and 19 can be smoothly changed while reducing the cost of the motors 29 and 34.

In this embodiment, a female screw is formed in a part of the left-right direction of the insertion hole 32a of the nut member 32, and this female screw is not formed in the whole area of the insertion-through hole 32a in the left-right direction. . Therefore, in this embodiment, the engagement length of the screw member 30 and the nut member 32 can be shortened. Therefore, in this embodiment, even if the nut member 32 inclines with respect to the screw member 30, it is reducing the contact resistance of the screw member 30 and the nut member 32 when the screw member 30 rotates. As a result, the capacity of the motor 29 can be further reduced.

Similarly, in this embodiment, a female screw is formed in a part of the left and right directions of the insertion through hole 37a of the nut member 37, and this female screw is formed in the entire region of the insertion through hole 37a in the left and right directions. Since it does not exist, the engagement length of the screw member 35 and the nut member 37 can be shortened. Therefore, in this embodiment, even if the nut member 37 inclines with respect to the screw member 35, it is reducing the contact resistance of the screw member 35 and the nut member 37 when the screw member 35 rotates. As a result, the capacity of the motor 34 can be further reduced.

In this embodiment, the forward screw portion 30a and the reverse screw portion 30b formed separately are connected by the coupling 42. Therefore, in this embodiment, compared with the case where the forward screw portion 30a and the reverse screw portion 30b are integrally formed, the length of the integrally formed portion of the screw member 30 can be shortened. . Therefore, it becomes possible to suppress the fall of the linearity of the screw member 30. FIG. Similarly, in this embodiment, since the forward screw portion 35a and the reverse screw portion 35b formed separately are connected by the coupling 42, the length of the integrally formed portion of the screw member 35 is shortened. As a result, it becomes possible to suppress the fall of the linearity of the screw member 35 as a result.

(Other embodiment)

Although the form mentioned above is an example of the suitable form of this invention, it is not limited to this, A various deformation | transformation is possible in the range which does not change the summary of this invention.

In the above-described form, square screws may be formed on the outer circumferential surfaces of the screw members 30 and 35 instead of trapezoidal screws. Also in this case, the same effects as in the above-described embodiment can be obtained. In addition, in the form mentioned above, the forward screw part 30a and the reverse screw 30b may be integrally formed, and the forward screw part 35a and the reverse screw 35b may be formed integrally. In addition, in the form mentioned above, a female screw may be formed in the whole area of the insertion through-hole 32a in a left-right direction, and a female screw may be formed in the whole area of the insertion-through hole 37a in a left-right direction.

In the form mentioned above, the cylindrical member 46 does not need to be equipped with the flange part 46b. In this case, the outer diameter of the head of the bolt 45 is larger than the inner diameters of the placement holes 32c and 37c. In the above-described embodiment, the fork pitch changing mechanisms 26 and 27 are provided as long as the nut members 32 and 37 are held by the slide members 31 and 36 so as to be movable in the direction perpendicular to the left and right directions. Does not have to have the cylindrical member 46. In this case, the shaft part of the bolt 45 is arrange | positioned, for example in the arrangement | positioning holes 32c and 37c. The inner diameter of the arranging holes 32c and 37c is larger than the outer diameter of the shaft part of the bolt 45, and the clearance gap is formed between the inner peripheral surface of the arranging holes 32c and 37c and the outer peripheral surface of the shaft part of the bolt 45. As shown in FIG. In addition, the outer diameter of the head of the bolt 45 is larger than the inner diameters of the placement holes 32c and 37c.

In the above-described form, one of the two forks 18 may be fixed in the left and right directions, and the other fork 18 may be movable in the left and right directions. In this case, the pitch of the two forks 18 is changed by moving the other fork 18 in the horizontal direction. Similarly, one fork 19 of the two forks 19 may be fixed in the left and right directions, and the other fork 19 may be movable in the left and right directions. In this case, the pitches of the two forks 19 are changed by moving the other forks 19 in the left and right directions.

In the form mentioned above, the pitch of the two forks 19 in the left-right direction may be fixed. In this case, the fork pitch change mechanism 27 becomes unnecessary. In this case, when the pitches of the two forks 18 are changed by the fork pitch changing mechanism 26, the pitches of the four forks 18 and 19 are also changed. Similarly, the pitches of the two forks 18 in the left and right directions may be fixed. In this case, the fork pitch change mechanism 26 becomes unnecessary. In this case, when the pitches of the two forks 19 are changed by the fork pitch changing mechanism 27, the pitches of the four forks 18 and 19 are also changed.

In the form mentioned above, the hand 3 does not need to be provided with two forks 18 or two forks 19. In other words, the number of forks included in the hand 3 may be two. In addition, the number of the forks which the hand 3 is equipped with may be three. In this case, for example, one fork arranged in the middle is fixed in the left and right direction, and the remaining two forks are moved in the left and right direction by the fork pitch changing mechanism. In this case, the pitches of the three forks are changed by one fork pitch changing mechanism. In addition, the number of the forks which the hand 3 is equipped with may be five or more. In this case, all five or more forks may be movable in the left-right direction, and there may be a fork fixed among the five or more forks fixed in the left-right direction.

In the above-described form, 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: return object
3: hand
4: arm
5: main body
18, 19: fork
26, 27: fork pitch changing mechanism
29, 34: motor
30, 35: screw member
30a, 35a: forward threaded
30b, 35b: Reverse thread part
31, 36: slide member
31c, 36c: screw hole
32, 37: nut member
32a, 37a: insertion through hole
32b, 37b: female thread
32c, 37c: placement hole
42: coupling
45: Bolt
46: cylindrical member
46a: cylindrical portion
50: guide mechanism
X: Long side direction of fork
Y: orthogonal direction

Claims (6)

In the hand of the industrial robot for conveying the object to be conveyed,
A plurality of forks formed in a straight line, a fork pitch changing mechanism for changing pitches of the plurality of forks in an orthogonal direction perpendicular to the long side direction and the vertical direction of the fork,
And a guide mechanism for guiding the fork in the orthogonal direction,
The fork pitch changing mechanism includes a motor serving as a drive source, a screw member connected to an output shaft of the motor with a trapezoidal screw or a square thread formed on an outer circumferential surface thereof, a nut member engaged with the screw member, and a proximal end side of the fork. And a slide member fixed to the
The nut member is held by the slide member so that movement in a direction orthogonal to the orthogonal direction is possible.
The fork pitch changing mechanism includes a cylindrical member having a bolt for attaching the nut member to the slide member, a cylindrical member formed in a cylindrical shape, and a cylindrical portion through which the bolt is inserted at an inner circumferential side thereof,
In the nut member, a round hole-shaped arrangement hole in which the cylindrical portion is disposed is formed so as to pass through the nut member in the orthogonal direction,
The slide member is formed with a screw hole in which the tip of the bolt is screwed in,
The inner diameter of the placement hole is larger than the outer diameter of the cylindrical portion,
The thickness of the said nut member in the said orthogonal direction is thinner than the length of the said cylindrical part in the said orthogonal direction, The hand characterized by the above-mentioned. delete The nut member of claim 1, wherein an insertion through hole through which the screw member is inserted is formed so as to pass through the nut member in the orthogonal direction.
And a female screw engaging with the trapezoidal screw or the angular screw in a portion of the insertion through-hole in the orthogonal direction. The hand according to claim 3, wherein the length in the orthogonal direction of the female screw portion in which the female screw is formed is 1.5 times the pitch of the trapezoidal screw or the angular screw. The said fork pitch change mechanism changes the pitch of two said forks,
The screw member includes a forward screw portion in which a forward screw is formed, a reverse screw portion in which a reverse thread is formed, and a coupling connecting the forward screw portion and the reverse screw portion,
The nut member held by the slide member fixed to the fork of one of the two forks is engaged with the forward screw portion,
And the nut member held by the slide member fixed to the fork on the other side of the two forks is engaged with the reverse screw portion. A hand according to any one of claims 1 and 3 to 5, an arm having the hand rotatably connected to the distal end side, and a main body portion rotatably connected to the proximal side of the arm. An industrial robot.

Images