JP3367797B2 - Manipulator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manipulator, and more particularly to a manipulator for processing a high-temperature work, for example, useful as a forging manipulator. 2. Description of the Related Art A hand of a manipulator such as a transfer machine has a hydraulic cylinder for driving a claw for gripping a work, and a parallel type or link opening / closing type hand is operated by the driving force of the hydraulic cylinder. The work is clamped and unclamped by opening and closing the claw. FIG. 4 is an explanatory view conceptually showing an example of a link opening / closing type hand according to the prior art. As shown in FIG. 1, a base member 1 is disposed at a distal end of an arm (not shown), and a claw constituted by a hydraulic cylinder 2 and a link mechanism driven by the hydraulic cylinder 2 to open and close the base member 1. 3a and 3b are provided. In such a hand, the hydraulic cylinder 2
The pin 4a,
The pawls 3a, 3b rotate in opposite directions about the rotation center 4b to open and close. Some manipulator hands are constructed so that the entire hand can rotate around a horizontal axis with the opening and closing operations of the claws 3a and 3b as described above. This type of prior art hand is, for example, a base member 1 shown in FIG.
To the hydraulic cylinder 2 by the hydraulic rotary actuator.
It is configured to rotate around a horizontal axis, which is the axial direction of. At this time, the hydraulic rotary actuator is disposed at the tip of the arm of the manipulator. [0006] As with the manipulator according to the prior art as described above, the claws 3a,
When a hydraulic cylinder 2 for opening and closing the claws 3a and 3b, a hydraulic rotary actuator for rotating the hand, and the like are provided near the workpiece 3b, if the workpiece is a high-temperature member such as a forged product, The effect of heat of the work causes a problem that the life of the consumable parts such as the O-ring and the oil seal of the actuator is shortened. Further, since the hand portion becomes bulky, not only is it difficult to work in a narrow space, but also dust-proof measures such as attaching a dust-proof cover to the hand portion may be required. In view of the above prior art, the present invention provides an actuator for driving a hand which is not affected by the heat of a workpiece, and which has a reduced size and a simplified structure of the hand, and has a predetermined space in a narrow space. Not only enable work,
An object of the present invention is to provide a manipulator capable of minimizing damage to each part due to a collision of a hand or the like. According to the present invention, there is provided a base member formed to be rotatable in a horizontal plane about a vertical axis as a center of rotation, a base end, and the base end. A cylindrical member having one end fixed to the part and protruding forward and having a distal end formed so as to be inferior in mechanical strength relative to the base end, and the base end is connected via a bearing. A hand arm supported by a base member and formed to be rotatable in a vertical plane about a horizontal axis as a center of rotation, and a pair of claws which are opened and closed to grip a workpiece, are disposed at a tip of the hand arm. The hand and the hand arm are inserted into the hand arm along the axial direction and linearly move in the axial direction to open and close the claws of the hand and are connected to the hand arm via splines. A tension shaft having a distal end formed to be freely bendable than the free joint; linear movement means provided on the base member for supplying a driving force for linear movement to the tension shaft; And a rotating means for supplying rotating power to the hand arm. According to the present invention having the above structure, the opening and closing of the claw is
The claw is moved via a tension shaft by driving a linear moving means provided on a remote base member. The rotation of the hand is performed via a hand arm by rotating means provided on a base member remote from the hand. Further, when an external force acts on the hand, the tension shaft is bent at the free joint to absorb the impact of the external force, and in some cases, the tip of the hand arm is damaged. Therefore, in any case, an excessive impact does not act on the actuators such as the linear moving means and the rotating means, and these actuators are protected against the impact acting on the hand. Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory view conceptually showing a manipulator according to this embodiment. As shown in the figure, this manipulator includes a one-axis member 1, a two-axis arm 2, a three-axis arm 3, 4,
This is a multi-joint manipulator having a shaft arm 4, a shaft 5, and a hand 6. The one-axis member 1 moves up and down along one axis 7 which is a vertical axis. In other words, the one-axis motor 9 disposed on the base 8 installed on the floor rotates the one-axis screw shaft, thereby vertically moving the one-axis member 1 screwed to the screw shaft. It is configured as follows. The base ends of the two-axis arm 2, the three-axis arm 3, and the four-axis arm 4 are respectively the one-axis member 1, the two-axis arm 2,
It is rotatably attached to the distal end of the triaxial arm 3 and is configured to rotate in a horizontal plane around the vertical axes of two axes 11, 3, 12, and 13. The driving sources at this time are a two-axis motor 14, a three-axis motor 15, and a four-axis motor 16, which are respectively disposed at the distal ends of the one-axis member 1, the two-axis arm 2, and the three-axis arm 3. The four-axis arm 4 has a five-axis arm 4
The hand 6 is driven by a shaft motor 17 so as to rotate the hand 6 in a vertical plane around the 5-axis 5 as a rotation center. In such a manipulator, one axis to five axes
The position and posture of the hand 6 are controlled by driving the shaft motors 9, 14, 15, 16, and 17. FIG. 2 is a plan view showing a part of the 4-axis arm 4 and the hand 6 shown in FIG. 1 which are extracted and enlarged and partially cut away, and FIG. 3 is a view showing the same part as that of FIG. It is explanatory drawing shown notionally. As shown in FIGS. 1 and 2, the four-axis arm 4 is provided with a base member 18, a hand arm 20 rotatably supported on the base member 18 via a bearing 19, and a rotating power of the hand arm 20. The rotation means is an AC servo motor 21 functioning as a 5-axis motor. The base member 18 rotates about the 4-axis 13 as a rotation center to be integrated with the other parts in a horizontal plane. It is configured to rotate inside. More specifically, the hand arm 20 is a cylindrical member having a base end 20a and a front end 20b having one end fixed to the base end 20a and protruding forward. The base end portion 20 a is supported by a bearing 19, and the rotational power of the AC servomotor 21 is transmitted when a gear 22 fixed to the outer periphery meshes with a gear 23. That is, the gear 23 is fixed to the output shaft of the speed reducer 24 that reduces the output of the AC servomotor 21. The distal end portion 20b is configured to have a lower mechanical strength relative to the proximal end portion 20a, and the hand 6 is fixed to the distal end. Thus, the hand arm 20 not only functions as a support arm for the hand 6, but also rotates the hand 6 in a vertical plane by driving the AC servomotor 21.
Also functions as an axis. The hand 6 has a hand body 25, a tension shaft 26, and an air cylinder 27 as a linear moving means. More specifically, the hand main body 25 has a frame 28 fixed to the tip of the hand arm 20 and a claw for clamping and unclamping a work (not shown) by opening and closing supported by the frame 28. 29
a, 29b. The tension shaft 26 is inserted into the hand arm 20 along the axial direction thereof, and has a rack 31 at a tip end thereof.
2a, 32b and these pinions 32
a and 32b mesh with the racks 33a and 33b, respectively. At this time, the pinions 32a and 32b
8 and is supported rotatably on the racks 33a, 3a.
3b is formed on the end face of the claws 29a, 29b on the frame 28 side. Therefore, when the tension shaft 26 linearly moves in the axial direction, the rack 31 and the pinion 32 are moved.
a, 32b and the claws 29 through the racks 33a, 33b.
a, 29b are linearly moved in the direction perpendicular to the axial direction of the tension shaft 26 and are opened and closed. The air cylinder 27 applies the driving force for the linear movement at this time. That is, the air cylinder 2
Reference numeral 7 is disposed on the base member 18, and the piston rod 27 a supports a thrust bearing 35 via a connecting rod 34. One end of the tension shaft 26 is supported by a thrust bearing 35. Thus, by driving the air cylinder 27, the piston rod 27a, the connecting rod 34, and the thrust bearing 35 move integrally,
As a result, the tension shaft 26 moves linearly and the claws 29a, 2
9b is opened and closed. Further, the tension shaft 26 in the present embodiment
Is divided into a base end portion 26a and a front end portion 26b, and both are connected by a free joint 36. Therefore, when an external force having a component perpendicular to the axial direction acts on the distal end portion 26b, the distal end portion 26b becomes the proximal end portion 26a.
Is bent at the free joint 36. The base end 26a is connected to the base 20a of the hand arm 20 via a ball spline 37. Thus, the tension shaft 26 rotates integrally with the hand arm 20 when the hand arm 20 rotates, and can perform linear movement independently. The potentiometer 38 is connected to the base end 20a of the hand arm 20 via gears 39 and 40,
The rotation amount of the hand arm 20 is configured to be detected. In this embodiment, the tension shaft 26, the rack 31, the pinions 32a and 32b and the racks 33a and 33a are driven by the air cylinder 27 which is disposed remotely from the hand main body 25, which is a portion for directly gripping the work.
The pawls 29a and 29b are opened and closed via 33b. Further, when a large external force acts on the hand body 25 due to a collision or the like, the tension shaft 30 is bent at the free joint 36, and the tip end 20b of the hand arm 20 is damaged depending on the magnitude of the external force. I do. Therefore, in any case, the impact force at this time is absorbed by the hand main body 25, the distal end portion 20b of the hand arm 20, and the distal end portion 26b of the tension shaft 26, and the base end portion 20b.
a, 30a and their connecting portions are not transmitted as an excessive impact force. According to the present invention, the actuator for opening and closing the claw of the hand is disposed remotely from the claw portion, as described in detail with the above embodiments. Since the structure of (1) can be simplified and the size of the portion can be reduced, a predetermined work can be quickly processed even in a narrow space. Further, even if the workpiece is a high-temperature member, it does not affect the actuator portion, and no special dustproof means is required. Further, the actuator and its coupling portion can be protected from a collision acting on the arm, and the maintenance can be facilitated because the broken portion can be minimized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view conceptually showing a manipulator according to an embodiment of the present invention. FIG. 2 is a plan view showing a four-axis arm and a hand part of FIG. 1 extracted and enlarged and partially cut away. FIG. 3 is an explanatory view conceptually showing the same part as in FIG. 2 for explaining the operation of the same part. FIG. 4 is an explanatory view showing an example of a hand of a manipulator according to the related art. [Description of References] 4 4-axis arm 6 Hand 18 Base member 19 Bearing 20 Hand arm 20a Base end 20b Tip 21 AC servomotor 26 Tension shafts 29a, 29b Claw 30a Base end 30b Tip 36 Free joint

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-151239 (JP, A) JP-A-61-159396 (JP, A) JP-A-6-31983 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) B25J 15/08 B25J 19/06 B21J 13/10

Claims (1)

(57) [Claim 1] A base member formed to be rotatable in a horizontal plane about a vertical axis as a center of rotation, a base end portion and one end fixed to the base end portion and forward. It is a cylindrical member having a distal end that protrudes and is formed so that the mechanical strength relative to the proximal end is inferior, and the proximal end is supported by a base member via a bearing, and the horizontal shaft is A hand arm formed to be rotatable in a vertical plane as a center of rotation, a hand disposed at a tip of the hand arm having a pair of claws for opening and closing to grip a workpiece, and an inside of the hand arm. It is inserted along the axial direction and linearly moves in the axial direction to open and close the claw of the hand, and is connected to the hand arm via a spline.Moreover, a free joint is interposed in the middle and the tip of this free joint is A tension shaft formed to be freely bent, a linear moving means provided on the base member for supplying a driving force for linear movement to the tension shaft, and a linear motor provided on the base member for supplying a rotating power to the hand arm. And a moving means.