JP2014131821A - Rotary plural-component gripping tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a plural-component gripping tool that is inexpensive, simple in structure, capable of switching over among a plurality of hands in a short time, and ensuring high efficiency.SOLUTION: A gripping tool includes: a plurality of component gripping portions 25 each including a lifting mechanism; and a rotational index 22b on which the component gripping portions 25 are installed on a same circumference as that of a robot end effector shaft 11. Only a component gripping portion 25a corresponding to a gripping target moves downward whereas the other component gripping portions 25b either move upward or are each kept at an elevated position or an intermediate position. The rotational index 22b is rotated until a central axis of the component gripping portion 25a moving downward matches the robot end effector shaft 11, and phase holding devices 21a, 21b, 23a, and 23b hold a phase of this state.

Description

  The present invention relates to a structure of a robot hand that grips a plurality of components in a robot used in a production line or the like, and more particularly to a rotary multiple component gripping tool that grips a plurality of components efficiently with a simple structure. .

Recently, production lines are being automated to reduce production costs and stabilize quality, and robot automation has been introduced into many production lines due to its versatility.
Here, in a production system using a robot, various hands capable of gripping a plurality of parts with one hand have been proposed in order to cope with an improvement in production efficiency and variable-variable production.
A structure of a multi-fingered hand similar to a human (for example, Patent Document 1) is constructed, and the phase and bending state of the finger are controlled to support various parts.
In addition, by aligning multiple cores on the left and right sides of the hand, according to the shape of the part to be grasped, passively operate, change the amount of extrusion, and fix it, so that various parts can be securely grasped. This is realized (for example, Patent Document 2).
Furthermore, it is a turret hand (for example, Patent Document 3 and Patent Document 4) in which a conventional hand mechanism is mounted on a plurality of tool mounting portions and rotated according to a gripping target.

JP 2008-178939 A (paragraph [0004], FIG. 2) JP-A-5-169387 (paragraphs [0005] to [0006], FIG. 1 and FIG. 2) Japanese Patent Laid-Open No. 5-111892 (paragraph [0007], FIG. 2) JP 2000-334688 (paragraph [0008], FIG. 1)

  In the automation of production lines using robots, it is required to respond to the changes in product types and production amounts from the recent high-mix low-volume production to variety-variable production. Therefore, it is important to reduce setup change loss when changing models. Therefore, the robot hand reliably grips multiple parts with different shapes and installs the parts on a pallet or assembly jig, making it easy to avoid interference with the work environment in addition to reproducibility of the gripping position and orientation. Sex is required. Further, in order to reduce the production cost, it is also required that the tact can be shortened, the area production efficiency can be improved, and the system can be configured with an inexpensive system.

In Patent Document 1, it is noted that a human finger has high flexibility with respect to the shape of a target object, and has a multi-joint structure similar to that of a human finger. As shown in Patent Document 1, it is composed of three or four finger structures, and by controlling the angle of each joint according to multiple parts with different shapes, the fingers can be made into a desired shape and can be securely gripped. It is said.
However, the flexibility is too high, and there are many finger shapes that can be gripped with respect to the target part, and the criteria for judging the superior difference are unclear, and it is difficult to select the optimum shape. In addition, the gripping state greatly depends on the finger shape and the reproducibility of the gripping state is low for parts with complex shapes. Need to be confirmed. As a result, equipment costs increase and processing time is required, which increases tact time.

In Patent Document 2, a plurality of cores are arranged in a stretchable manner on the fingertip, and the amount of the plurality of cores to be taken in and out is determined along the shape of the gripping target. It has become.
However, a sliding structure such as a sliding bearing and an oil-free bush is indispensable for realizing smooth insertion and removal of the core, and it is difficult to reduce the size, resulting in an increase in component costs. Here, many materials used for sliding bearings and oil-free bushes have low magnetic permeability such as non-magnetic materials such as bronze materials and sintered members, and the electromagnets used for fixing during gripping become large. It is even more difficult to reduce the size of the hand.
In addition, since the gripping state is greatly affected by the friction between the multiple cores and the workpiece, it is not uniquely determined.When working with the position and orientation on the production line, the gripping state is determined by a visual sensor each time. Need to confirm. As a result, equipment costs increase and processing time is required, which increases tact time.
In addition, due to the structure, a large space for expansion / contraction operation is required on the left and right sides of the claw portion, and in addition to a component gripping / release space, a space for preventing interference is additionally required on the environment side.

Patent Documents 3 and 4 have a rotatable turret structure. These are equipped with multiple hands on the turret, and it is easy to grip multiple parts, and hands other than the target hand are placed in the horizontal direction or diagonally upward, so of course interference with the work The structure is easy to avoid interference with the environment.
However, in Patent Document 3, there is a restriction on the amount of interference avoidance. Since only the hand protrudes from the rotating turret due to the structure, the interference avoidance amount is determined by this hand length. When the hand claw is extended, the gripping force is reduced, so the hand length must be extended. This induces an increase in weight and an increase in size, increases the switching time, and requires a rotary drive source with a higher output. Further, there is always an offset between the tool axis and the hand center axis of the robot, and the horizontal plane position of the hand center axis changes due to the rotation of the tool axis, so that the teaching is difficult.

  On the other hand, in Patent Document 4, unlike Patent Document 3, the stepping motor, which is a turret rotation drive source, has a structure in which the posture is offset so that the hand central axis coincides with the robot axis, so that interference can be avoided more easily. And the problems in teaching have been solved. However, the number of hands that can be mounted and the ease of interference avoidance are in a trade-off relationship, and usually a plurality of hands of about 3 to 4 are common. In addition, since the configuration is approximately Y-shaped, when the number of installed hands is as small as two, compared to hands with other structures, the size is increased and the weight is increased, thus avoiding interference. There are problems such as problems and restrictions on high-speed operation.

  The present invention has been made to solve the above-mentioned problems, and (1) the gripping position is reproducible, (2) it has a weight and a size corresponding to the number of plural hands to be installed, (3) The objective is to obtain an inexpensive multi-component gripping tool that is easy and sufficient to avoid not only parts but also interference with the work environment, and (4) short switching time of multiple hands.

  A plurality of component gripping tools according to the present invention includes a plurality of component gripping units having a moving mechanism that moves on a straight line, a rotation index in which the plurality of component gripping units are installed on the same circumference as the robot end effector shaft, Driving means for selectively driving a movement mechanism of the plurality of component gripping portions to perform a movement operation in one direction for gripping a component with respect to any of the plurality of component gripping portions; and the component gripping by the driving means A rotation drive means for rotating the rotation index so that the central axis of the component gripping part coincides with the robot end effector axis in synchronization with the movement of the part in the one direction, and a component corresponding to the gripping target Only the gripper moves in the one direction, and the other component gripper moves in the other direction or holds the intermediate position and detects the rotation phase to detect the one direction. The central axis of the component gripping portion for a movement of, rotates the rotary index until it matches the robot end effector axis, which is constituted to hold the phase in this state.

  According to the present invention, in the gripping operation of a plurality of parts, since the operation of moving the central axis of the target gripping part to the robot end effector axis and the movement operation of the target gripping part are realized at the same time, the switching time can be shortened and the setup change loss. Reduction or system flexibility is improved. In addition, it is possible to easily teach the robot and to prevent interference between the operating environment and the gripping tool.

BRIEF DESCRIPTION OF THE DRAWINGS It is a whole structure conceptual diagram in Embodiment 1 of this invention. It is a side view of the rotary type multiple component holding tool in Embodiment 1 of this invention. It is a schematic diagram regarding the compressed air piping connection in Embodiment 1 of this invention. It is a schematic diagram regarding the compressed air piping connection in Embodiment 2 of this invention. It is a schematic diagram explaining the operation | movement in Embodiment 3 of this invention. It is a schematic diagram regarding the compressed air piping connection in Embodiment 3 of this invention. It is a side view of the rotary type multiple component holding tool in Embodiment 4 of this invention. It is explanatory drawing regarding the gear structure in Embodiment 4 of this invention. It is a schematic diagram explaining the operation | movement in Embodiment 4 of this invention. It is a side view of the rotary type multiple component holding tool in Embodiment 5 of this invention. It is a front view of the rotation linear motion conversion mechanism which can switch forward rotation / reverse rotation in Embodiment 5 of this invention. It is a schematic diagram explaining the operation | movement in Embodiment 5 of this invention.

Embodiment 1 FIG.
FIG. 1 shows an overall overview of a robot 1 and a rotary multi-component gripper 2 according to Embodiment 1 of the present invention. As an example of the robot 1, a horizontal articulated robot having a total of four degrees of freedom of three axes (J1, J2, J3) substantially parallel to the vertical axis and a linear motion axis (J4) in the vertical axis direction will be described.
The final axis J4 is the end effector axis 11, and the final axis is the end effector axis 11 in the case of another type of robot such as a vertical articulated robot.
The rotary multiple component gripping tool 2 is fixed to the end effector shaft 11 and includes a plurality of component gripping portions 25a and 25b for gripping and releasing components, and one component gripping portion 25a (a lowered position side component gripping portion). And the end effector shaft 11 are made to coincide with each other. Thereby, since the rotation of the end effector shaft 11 becomes the rotation of the component gripping portion 25a, teaching in the operation using the component gripping portion 25a is facilitated. In addition, the use of the lifting mechanism can easily avoid interference with the work environment.

Next, the detailed structure of the rotary multiple component gripper 2 will be described. FIG. 2 shows a side view of the rotary multi-component gripping tool 2 according to Embodiment 1 of the present invention. The connection adapter 21 is fixed to the end effector shaft 11. Further, a rotation drive source 22a is fixed below the connection adapter 21, and the rotation shaft is connected to the rotation index 22b. Further, the rotary index 22b includes two air cylinders 24a and 24b that are moving mechanisms that linearly reciprocate the component gripping portions 25a and 25b and that are lift mechanisms with the component gripping portions 25a and 25b fixed to the tips. It is fixed.
That is, a plurality of component gripping portions 25 a and 25 b are installed on the same circumference as the robot end effector shaft 11. The component gripping portions 25a and 25b are arranged in a phase that is symmetrical with respect to the x-axis or the y-axis of the end effector coordinate in the end effector shaft 11. The phase interval between the two component gripping portions 25a and 25b is 180 degrees. Thus, when the rotation index 22b is rotated by the rotation drive source 22a, the two air cylinders 24a and 24b, and thus the component gripping portions 25a and 25b rotate. Since the center axis of the component gripping portion 25a matches the end effector shaft 11, when the rotation index 22b rotates 180 degrees, the center axis of the component gripping portion 25b also matches the end effector shaft 11, and the component gripping The teaching work for not only the part 25a but also the component gripping part 25b is facilitated.

Further, the position restricting portions 21 a and 21 b protrude downward from the lower surface of the connection adapter 21. On the other hand, the position restricting movable portions 23a and 23b protrude upward from the upper surface of the rotation index 22b. Since these come into contact with the rotation of the rotation index 22b, it is possible to reliably determine the phase. These detections can be realized by a position detection sensor which is a known technique (not shown). By these phase detection means, it is possible to detect a phase state in which the central axis of the component gripper coincides with the robot end effector axis.
Here, while the compressed air is applied, the position restricting portions 21a and 21b and the position restricting movable portions 23a and 23b are in contact with each other, and the phase state in which the central axis of the component gripping portion coincides with the robot end effector axis. Since these can be held, they also function as phase holding means.

In FIG. 3, the schematic diagram regarding the compressed air piping connection by Embodiment 1 of this invention is shown. Pipes 27a and 27b are connected from an output port of a double solenoid valve 26 constituted by a four-way solenoid valve for air cylinder control, and are connected to a rotary drive source 22a and double-acting air cylinders 28a and 28b. The double-acting air cylinders 28a and 28b are connected such that the lifting / lowering operation is in the opposite direction. In the figure, compressed air is supplied to the pipe 27a side by the double solenoid valve 26, the component gripping portion 25a is in the lowered position, and the component gripping portion 25b is in the raised position. The rotation drive source 22 a is pressurized in a direction in which the component gripping portion 25 a coincides with the end effector shaft 11. Next, when the double solenoid valve 26 is switched and compressed air is supplied to the pipe 27b side, the double acting air cylinder 28a on the component gripping portion 25a side moves upward, and the double acting air cylinder 28b on the component gripping portion 25b side turns on. In addition, the rotation driving source 22a rotates in the direction in which the component gripping portion 25b coincides with the end effector shaft 11.
That is, the solenoid valve that supplies the compressed air and the air cylinder constitute an elevating drive unit that moves the component gripping portion up and down. In addition, the rotation drive source 22a sharing the lift drive means and the air piping constitutes a rotation drive means for rotating the rotation index in synchronization with the descending operation of the component gripping portion.

Thus, when there are two component gripping portions, the piping connection of the double-acting air cylinders 28a and 28b may be half that of the normal case, and only one double solenoid valve 26 is required. Wiring can be easily routed, and the required equipment can be halved, so an inexpensive system can be constructed.
In addition, since the compressed air device is also used for the rotation drive source 22a, piping and wiring can be further facilitated, and the lifting / lowering operation and rotation of the component gripping portions 25a and 25b required when switching the gripping target components. Since the operations are synchronized, reliable switching can be realized and switching time can be shortened.

Embodiment 2. FIG.
In the present embodiment, only the lifting mechanism and its pneumatic circuit are different from those in the first embodiment, and therefore the description of the structure is omitted here. FIG. 4 shows a schematic diagram relating to compressed air piping connection in Embodiment 2 of the present invention. In the present embodiment, a single action type is used as the lifting mechanism. The single-acting air cylinders 31a and 31b serving as the lifting mechanisms perform the opposite operations when compressed air is supplied. That is, the initial position of the rotary drive source 32 is determined so that the retractable single-acting air cylinder 31a coincides with the end effector shaft 11, and the push-out single-acting air cylinder 31b is the other.
A pipe 34 is connected from an output port of a single solenoid valve 33 composed of a two-way solenoid valve for air cylinder control, and is connected to a rotation drive source 32, a retractable single acting air cylinder 31a, and an extruded single acting air cylinder 31b. Yes. Thus, when compressed air is applied, the retractable single-action air cylinder 31a starts the upward movement against the spring, and the push-out single-action air cylinder 31b starts the downward movement against the spring. The gripping portion 25a starts the ascending operation, and the component gripping portion 25b starts the descending operation. In synchronization with this, the rotational drive source 32 also resists the spring, and the component gripping portion 25b rotates in a direction that coincides with the end effector 11 axis.

Thus, when there are two component gripping portions, the piping connection of the single acting air cylinders 31a and 31b may be 1/4 of the normal case, and the single solenoid valve 33 may be one, It is easy to route piping and wiring.
Furthermore, since the compressed air device is also used for the rotation drive source 32, the piping and wiring are further facilitated, and the lifting and lowering operations of the component gripping portions 25a and 25b required when switching the gripping target components are synchronized. Since it operates, reliable switching can be realized and switching time can be shortened. Furthermore, since a single-action air cylinder is used, the amount of compressed air used can be halved, so that a system with a low running cost can be constructed.

Embodiment 3 FIG.
Next, a case where there are four component gripping portions will be described. FIG. 5 shows a schematic diagram for explaining the operation in the third embodiment of the present invention. It is a general explanatory view of a rotary multiple gripping tool (not shown) viewed from above. Four phases 43a to 43d are set at equal intervals on the same circumference of the rotation index 41, and the central axis 42 becomes the central axis of a rotation drive source (not shown). Further, the phase 43a matches the end effector shaft 11 (not shown).

In FIG. 6, the schematic diagram regarding the compressed air piping connection in Embodiment 3 of this invention is shown. Four component gripping portions 45a to 45d are fixed to four push-type single-acting air cylinders 44a to 44d, and single solenoid valves 46a to 46d composed of two-way solenoid valves for air cylinder control are connected. Has been. Here, the suffixes a to d in FIGS. 5 and 6 correspond to each other.
FIG. 6 shows a situation in which the component gripping portion 45a performs a gripping operation. The single solenoid valve 46a is turned on, compressed air is supplied to the push-out single acting air cylinder 44a, and the component gripping portion 45a is in the lowered position. It will be in a certain state. Since the compressed air is not supplied to the other single solenoid valves 44b to 44d, the component gripping portions 45b to 45d are in the raised position and do not interfere with the work environment.

When changing the object to be gripped, the single solenoid valve before the change is turned off, and the single solenoid valve after the change is turned on to perform the ascending and descending operations, respectively. A desired phase determination and phase holding are realized by a phase holding mechanism using a rotating phase detector and a holding mechanism such as an electromagnet which is a known technique. That is, any one of the single solenoid valves 44a to 44d to be gripped is selectively switched to the ON state, and the other single solenoid valves that are not gripped in the single solenoid valves 44a to 44d are turned to the OFF state. That is, a control operation by selective ON / OFF switching operation is performed.
By performing such a configuration and control, when the supply of compressed air is stopped, all the component gripping portions 45 are in the raised position, so that interference can be avoided and wiring and piping are also double-acting air cylinders Therefore, an inexpensive system configuration is possible.
Furthermore, since a single-action air cylinder is used, it is not necessary to supply compressed air and maintain the upper position, so that the amount of compressed air used can be suppressed and a system with low running cost can be constructed.
Here, the rotational drive source is not described in detail, but can be easily realized by using a known technique such as an index table.
In addition, although the case of four was shown here, the same structure can be implement | achieved and the same effect can be acquired also in the case of three and the case of five or more.

Embodiment 4 FIG.
In FIG. 7, the side view of the rotary multiple components holding tool 5 in Embodiment 4 of this invention is shown. The connection adapter 21 is fixed to the end effector shaft 11. A sun gear 51 is fixed below the connection adapter 21. A rotation drive source 52 is fixed below the sun gear 51, and the rotation holding portion 52b is rotatable via a rotation shaft 52a.
Two planetary gears 53a and 53b are fitted to both ends of the sun gear 51, and their rotation shafts are connected to the rotation / linear motion conversion mechanisms 54a and 54b via a coupling (not shown) or a gear (not shown). Is done. Here, a general device using a ball screw is assumed as the rotation / linear motion conversion mechanisms 54a and 54b, but it goes without saying that a similar configuration can be realized by a known conversion mechanism. Here, the rotation / linear motion conversion mechanism 54 is fixed to the rotation holding unit 52b, and rotates together with the planetary gear 53 as the rotation drive source 52 rotates.
In addition, since the component gripping portion 55a installed below the rotation / linear motion converting mechanism 54a coincides with the end effector shaft 11, teaching can be easily realized. Although details will be described later, teaching can be easily realized because the component gripping portion 55b installed below the rotation / linear motion conversion mechanism 54b also coincides with the end effector shaft 11 by the rotation of the rotation drive source 52.

  Next, the operation will be described. FIG. 8 is an explanatory diagram relating to a gear structure according to Embodiment 4 of the present invention. In order to help understanding, it is a schematic drawing. The sun gear 51 is fixed to the end effector shaft 11 via the connection adapter 21. The planetary gear 53 is rotatably fixed to a carrier 56 corresponding to the rotation holding portion 52b in FIG. The carrier 56 is rotated around the central axis of the sun gear 51 by a rotation drive source (not shown). That is, the planetary gear mechanism is formed by the sun gear 51, the planetary gear 53, and the carrier 56. Here, the right planetary gear 53a is in a phase coincident with the end effector shaft 11, the component gripping portion 55a on the planetary gear 53a side is in the lowered position, and the component gripping portion 55b on the planetary gear 53b side is in the raised position. ing. Further, the threading method of the ball screw constituting the rotation / linear motion converting mechanism 54 is reversed. The ball screw on the planetary gear 53a side is a right-hand screw type, and the ball screw on the planetary gear 53b side is a left-hand screw type. That is, when the carrier 56 is rotated by a rotation drive source (not shown) in the direction indicated by the carrier rotation direction 57 (clockwise toward the paper surface in the drawing), the planetary gear 53 is also rotated clockwise. The planetary gear 53a side moves upward from the right screw, and the planetary gear 53b side moves downward from the left screw. Here, the lifting / lowering operation amount of the rotation / linear motion conversion mechanism 54 is determined by the above-described diameter ratio, the lead of the ball screw, and a gear (not shown).

  FIG. 9 is a schematic diagram for explaining the operation in the fourth embodiment of the present invention. As in FIG. 8, a clockwise rotation (carrier rotation direction 57) is considered. Each shows a case where the carrier 56 is rotated at intervals of 90 degrees. In FIG. 5A, the planetary gear 53a side is in the lowered position and the planetary gear 53b side is in the raised position. As shown in FIG. 5B, when the carrier 56 rotates 90 degrees clockwise, the planetary gear 53a side moves upward because the right-hand screw rotates clockwise, and on the planetary gear 53b side, the left-hand screw rotates clockwise. To move down. When the 90-degree carrier 56 further rotates in the same direction, the same operation is further performed ((c) in the figure), the phase of the planetary gear 53a and the planetary gear 53b is reversed, and the planetary gear 53a side is at the ascending position. The gear 53b side is in the lowered position, and switching of the component gripping portion can be realized. Here, since the amount of rotation and the amount of elevation are in a proportional relationship, in FIG. 5B, they exist at an intermediate position between the ascending position and the descending position.

Thus, by reversing the screw cutting direction in the rotation / linear motion conversion mechanism 54, the phase conversion and the elevation can be synchronized with one rotational drive source, and a reliable switching operation can be performed and the switching time can be reduced. Shortening is possible.
Here, the phase detection of the rotational drive source 52 can be realized by a known technique such as an encoder. Needless to say, the phase holding mechanism can be easily realized by using a servo or a brake.

Embodiment 5 FIG.
Next, a case where there are four component gripping portions will be described. In FIG. 10, the side view of the rotary multiple components holding tool 6 in Embodiment 5 of this invention is shown. The connection adapter 21 is fixed to the end effector shaft 11. A sun gear 51 is fixed below the connection adapter 21. A rotation drive source 52 is fixed below the sun gear 51, and the rotation holding unit 62 can be rotated via a rotation shaft.
Four planetary gears 61 a to 61 d are fitted to both ends of the sun gear 51, and the rotation shaft thereof is connected to the drive shaft of the rotation / linear motion conversion mechanism 63 that can be switched between forward rotation and reverse rotation. Further, since the rotation / linear motion conversion mechanism 63 capable of switching between normal rotation and reverse rotation is fixed to the rotation holding unit 62, each planet gear 61 rotates around the rotation axis of the rotation drive source 52, so The component gripper 64 can be made to coincide with the end effector shaft 11 by the rotation operation.

  FIG. 11 shows a front view of a rotation / linear motion conversion mechanism 63 capable of switching between normal rotation and reverse rotation in Embodiment 5 of the present invention. The rotation shaft of the planetary gear 61 is connected to the gear 65b. The gear 65b is engaged with the gear 65a to transmit the rotation. The gear 65a and the gear 65b are connected to a right-handed ball screw 67a and a left-handed ball screw 67b via a clutch 66a and a clutch 66b, respectively. The movable table 68 has female threads for right and left threads. Accordingly, when the clutch 66a is connected and the clutch 66b is released, the planetary gear 61 rotates through the gear 65a and the right-handed ball screw 67a through the clutch 66a, and as a result, the movable table 68 moves. It will be. At this time, with the movement of the movable table 68, the left-handed ball screw 67b is rotated in the opposite direction to the right-handed ball screw 67a. That is, the rotation direction is reversed at the boundary of the clutch 66b. On the other hand, when the clutch 66a is released and the clutch 66b is connected, the left-handed ball screw 67b rotates in the same manner, and as a result, the movable table 68 operates in the reverse direction.

  As described above, even when the planetary gear 61 rotates in one direction, forward / reverse rotation can be freely controlled by switching the clutch 66. Here, since the casing 69 is fixed to the rotation holding unit 62, the lifting / lowering operation and rotation of the component gripping unit 64 are controlled by controlling the lifting / lowering operation of the component gripping unit 64 according to the rotation of the rotation driving source 52. Since the operations can be synchronized, a reliable switching operation can be performed and a switching time can be shortened.

  If the gear ratio of the gears 65a and 65b is adjusted to increase the speed, the amount of lifting can be secured with the speed increasing gear, so the phase interval on the rotation index is narrow, and thus a large number of component gripping parts are installed. It becomes possible.

  FIG. 12 is a schematic diagram for explaining the operation in the fifth embodiment of the present invention. The sun gear 51 is fixed, and the planetary gear 61 is rotatably fixed to the cross-shaped carrier 71 at intervals of 90 degrees. Here, the carrier 71 includes a casing 69 and a rotation holding unit 62 of a rotation / linear motion conversion mechanism 63 that can be switched between forward rotation and reverse rotation. At a phase where the planetary gear 61a coincides with the end effector shaft 11, the component gripping portion exists at the lowered position. On the other hand, the planetary gear 61b and the planetary gear 61d are in the intermediate position, and the planetary gear 61c is in the raised position. As shown in FIG. 12A, the case of the carrier rotation direction 72a, that is, the case of rotating clockwise in the figure is considered. With respect to the clockwise direction, the right screw side is raised and the left screw side is lowered, so that the planetary gears 61a and 61b to be raised are connected to the right screw side clutch and the planetary gears 61c and 61d to be lowered are By connecting the left screw side clutch, the desired position of the component gripping portion can be obtained by 90 ° rotation. On the other hand, as shown in FIG. 12B, in the case of the carrier rotation direction 72b, that is, when rotating in the counterclockwise direction in the figure, the right screw side is lowered and the left screw side is raised. By connecting the planetary gears 61a and 61d to be made to the left screw side and the planetary gears 61b and 61c to be lowered to the right screw side, a desired component gripping portion position can be obtained.

In this way, by simply switching the clutch 66 in accordance with the rotation of the carrier 71, the lifting operation can be controlled, the target component gripping part can be set in a desired phase, and the synchronous operation can be performed up to the lowered position. A reliable switching operation can be performed and the switching time can be shortened.
In addition, here, a structure using a right-handed screw, a left-handed ball screw and a clutch is shown as the forward / reverse switching mechanism, but the same effect can be obtained even by using a reversing mechanism which is a known technique. Can do.
Although the case of four is shown here, in the case of three, the same configuration can be realized in the case of five or more, and the same effect can be obtained.

Further, in the description so far, the description has been made in the form in which the plurality of gripping parts move up and down, but the present invention can be applied even when the gripping part moves horizontally or moves diagonally. That is, when one gripping part moves in one direction, the other gripping part moves in the opposite direction.
Here, in the first and second embodiments, for the sake of simplicity, the case where the two component gripping portions are arranged at an interval of 180 degrees, that is, at an equal interval has been described. Similar effects can be obtained.
Further, in the first to third embodiments, in order to easily and reliably realize the synchronization of the lifting operation and the rotation operation, the rotary drive sources 22a and 32 are used as the air rotating device using the compressed air. By controlling the known rotational drive source in accordance with the signal to the solenoid valve, the same effect can be obtained in reducing the routing of piping other than the rotational drive sources 22a and 32.
Furthermore, in Embodiments 1 to 3, a system using compressed air is used. However, similar effects can be obtained by using known techniques such as a linear motion mechanism using a fluid such as a hydraulic cylinder. It goes without saying.
Further, in the second and third embodiments, the single-action air cylinder is used, but the same effect can be obtained with a structure in which an elastic body is installed outside the air cylinder and biased in one direction.

Here, the component gripping part that does not grip the component is arranged in front of the end effector shaft 11, but either may be used as long as interference can be avoided even in the reverse configuration.
In addition, although the interval between the component gripping tools is equal, the use of a known technique such as an electric motor and an encoder for the rotation drive source is not limited to the equal interval, and similar effects can be obtained. Needless to say.
Furthermore, for the sake of simplicity, the case where a plurality of chuck types having different claw shapes are arranged one by one as the component gripping portion has been described here. However, vacuum chucking methods other than chucking methods, magnet adsorption methods, and electromagnet adsorption methods are used. However, it goes without saying that a plurality of component gripping portions may be installed in one lifting mechanism.

  It should be noted that within the scope of the present invention, a part or all of each embodiment can be freely combined, or each embodiment can be appropriately modified or omitted.

  DESCRIPTION OF SYMBOLS 1 Robot, 11 End effector axis | shaft (J4 axis | shaft), 2 rotary type multi-component holding tool, 21 Connection adapter, 21a Position control part a, 21b Position control part b, 22a Rotation drive source, 22b Rotation index, 23a Position control movable part a, 23b Position regulating movable part b, 24a, 24b Air cylinder, 25a, 25b Parts gripping part, 26 Double solenoid valve, 27a, 27b Piping, 28a, 28b Double acting air cylinder, 31a Retractable single acting air cylinder, 31b Extrusion Type Single Action Air Cylinder, 32 Single Action Air Rotating Cylinder, 33 Single Solenoid Valve, 34 Piping, 41 Rotation Index, 42 Center of Rotation, 43a-43d Phase, 44a-44d Extrusion Type Single Action Air Cylinder, 45a-45d 46a-46d single Solenoid valve, 5 rotary multi-component gripper, 51 sun gear, 52 rotary drive source, 52a rotary shaft, 52b rotation holding portion, 53a, 53b planetary gear, 54a, 54b rotation linear motion conversion mechanism, 55a, 55b component gripping portion , 56 carrier, 57 direction of carrier rotation, 6-rotating multi-component gripper, 61a to 61d planetary gear, 62 rotation holding unit, 63 rotation / linear motion conversion mechanism capable of switching between forward and reverse rotation, 63a to 63c forward / reverse rotation Switchable rotation linear motion conversion mechanism, 64a to 64c parts gripping part, 65 gear, 66 clutch, 67a right-handed ball screw, 67b left-handed ball screw, 68 movable table, 69 housing, 71 carrier, 72a, 23b carrier rotation Direction.

Claims (10)

  A plurality of component gripping portions having a moving mechanism that moves on a straight line; a rotation index in which the plurality of component gripping portions are installed on the same circumference as the robot end effector shaft; and a movement mechanism of the plurality of component gripping portions. Driving means for selectively driving and moving in one direction to grip a component as a gripping object for any of the plurality of component gripping portions; and the one direction of the component gripping portion by the driving means A rotation driving means for rotating the rotation index so that a central axis of the component gripping part coincides with the robot end effector axis in synchronization with the movement operation to the robot, and only the component gripping part corresponding to the gripping target is provided. The moving operation in the one direction is performed, and the other component gripping unit performs the moving operation in the other direction or holds the intermediate position, and detects the rotation phase to detect the one direction. Rotating multiple parts gripping, characterized in that the rotation index is rotated until the center axis of the part gripping part performing the moving operation coincides with the robot end effector axis, and the phase is maintained in this state. Ingredients.   Selectively driving a plurality of component gripping portions having a lifting mechanism, a rotation index where the plurality of component gripping portions are installed on the same circumference as the robot end effector shaft, and a lifting mechanism of the plurality of component gripping portions; A raising / lowering driving means for performing a lowering operation for gripping a component with respect to any of the plurality of component gripping portions, and the rotation index is synchronized with a lowering operation of the component gripping portion by the lifting / lowering driving means. Rotational drive means for rotating the central axis to coincide with the robot end effector axis, and phase detection means for detecting a phase state in which the central axes of the plurality of component gripping parts coincide with the robot end effector axis. And a phase holding means for holding the rotation index in the phase state detected by the phase detecting means. Rotating multi-part gripping tools.   3. The rotary multi-part according to claim 2, wherein the elevating mechanism is composed of an air cylinder, and the part gripping part to be moved up and down is selected by switching an air cylinder control solenoid valve. Gripping tool.   The two component gripping parts are arranged in a phase that is symmetric with respect to the x-axis or y-axis of the end effector coordinate in the robot end effector axis, and the lifting / lowering operations of the two component gripping parts are reversed in the vertical direction. 4. The rotary multi-component gripping tool according to claim 3, wherein the rotary multi-component gripping tool is pipe-connected so as to operate.   The lifting mechanism is composed of two single-acting air cylinders, with one single-acting air cylinder being a push-out type, and the other single-acting air cylinder being a retractable type by a compression spring installed in the single-acting air cylinder 5. The rotary multi-component gripping tool according to claim 4, wherein the elevating mechanisms opposed to each other are configured to be opposite to each other.   The rotation operation of the rotation index is realized by a compression spring and an air cylinder that supplies compressed air that applies pressure to the compression spring, and a pipe that supplies the compressed air to the air cylinder is an air pipe of the lifting mechanism. The rotary multi-component gripping tool according to claim 4, wherein the rotary multi-component gripping tool is shared.   The component gripping portions are installed at equal intervals, planetary gears are installed on the input shaft side of the lifting mechanism composed of a ball screw linear motion device and a forward / reverse rotation mechanism portion, and on the robot end effector shaft side. Is a planetary gear mechanism in which a sun gear and a rotational drive source are fixed, and the rotational index serves as a carrier, and the forward / reverse mechanism is switched in accordance with the rotation of the rotational index, so that the component gripper is moved up and down. The rotary multi-component gripping tool according to claim 2, wherein   8. The rotary multi-component gripping tool according to claim 7, wherein the forward / reverse rotation mechanism is composed of a right screw, a left screw, and a clutch, and the right screw and the left screw are switched in accordance with the raising / lowering direction.   The two lifting mechanisms are ball screw linear motion devices that are arranged in a phase that is symmetric with respect to the x-axis or y-axis of the end effector coordinate in the robot end effector axis, and are composed of right and left screws. The planetary gear is supported on the ball screw rotating shaft above, the sun gear and the rotation drive source are fixed on the robot end effector shaft side, and the planetary gear mechanism is configured in which the rotation index serves as a carrier. The rotary multi-component gripping tool according to claim 7.   The rotary multi-component gripping tool according to claim 8 or 9, wherein a speed increasing gear is installed between the planetary gear and the ball screw in the lifting mechanism.

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