JPS6312950Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the improvement of a joint device for a robot, which allows it to be made smaller and lighter with a simple structure.

Various types of robots are used for work in adverse environments, work with hazardous materials, or work in narrow spaces where workers cannot directly enter, and are used for detailed and complex work. I'm letting them do it. For this reason, the wrist, etc. used for work must be able to point in any direction, and in conventional robots, for example, as shown in Figure 1, a y-axis pin is attached to the tip of arm 1, which is the robot body. A rotatable intermediate arm 3 is attached to the distal end of the intermediate arm 3 via an x-axis pin 4 that is perpendicular to the y-axis pin 2, and a base end of a wrist portion 5 is rotatably provided. The intermediate arm 3 is driven by a drive mechanism (not shown) provided in the arm 1.
The wrist portions 5 are each driven by a drive mechanism (not shown) provided within the intermediate arm 3.

However, in the above structure, since the intermediate arm 3 is provided and the y-axis pin 2 and the x-axis pin 4 are provided orthogonal to each other, the wrist portion 5 is located forward by the length of the intermediate arm 3, and the robot body There are problems such as the weight of the tip being greater than that of the arm 1, which leads to an increase in the size of the robot, and the working range of which is restricted.

As shown in Figure 2, a method for downsizing a robot is to
It is conceivable to be able to perform power operation with two degrees of freedom at one point so that the robot can rotate by α in the z-y plane and β in the x-y plane around mechanism is known. In this mechanism, a ring-shaped member 7 is supported between two fixing members 6 by shafts 8a, 8b on its diameter, and a disk-shaped member 9 is supported within the ring-shaped member 7 by shafts 10a, 10a, 10b, which are orthogonal to the axes 8a, 8b. It is supported by 10b. The ring-shaped member 7 can be rotated by an angle β around the axes 8a and 8b (zz axis), and the disc-shaped member 9 can be rotated around the axis 1.
Since it is possible to rotate the α angle around 0a and 10b (x-x axes), the disc-shaped member 9 can arbitrarily take two degrees of freedom with respect to the fixed member 6, which is the composite angle of the α angle and the β angle. .

However, in the above-mentioned mechanism, conventionally,
Since a link is used to operate the disk-shaped member 9 from the fixed member 6 side, there is a drawback that the operating angles α and β cannot be set large. In addition, in order to transmit power further through this universal joint, if we try to accommodate the operating angles α and β, a universal joint or the like is used as a power transmission mechanism, so in the end, the mechanism cannot be used. This is a combination of two joints with one degree of freedom, resulting in a fairly large product.

The present invention was developed in view of the current situation, and aims to provide a joint device for a robot that has a simple structure, is compact and lightweight, and is also capable of transmitting power to the other side.

The structure of the present invention that achieves the above object is a support base that rotatably supports a support drive shaft and a drive force transmission shaft that intersects with the support drive shaft and to which rotational force from the support drive shaft is transmitted. a rocking ring arranged to surround the support base and rotatably supporting the support base via a support shaft that is coaxial with the support drive shaft; a ring drive mechanism provided on the robot body to swing the swing ring around the swing shaft; a ring drive mechanism that swings the swing ring around the swing shaft; two ring-shaped power transmission members rotatably fitted to the rocking ring on the inner and outer peripheral sides of the rocking ring around an axis that intersects with the shaft; two power transmission member drive mechanisms that independently rotate these two power transmission members via respective drive shafts that are provided and are coaxial with the swing shaft; one of the power transmission members and the support base; a support drive transmission mechanism that is provided between the support base and rotates the support base around the support shaft; and a support drive transmission mechanism that is provided between the other power transmission member and the support drive shaft. It is equipped with a transmission shaft drive transmission mechanism that rotates the transmission shaft.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a robot joint device according to the present invention will be described in detail based on an embodiment shown in the drawings.

FIGS. 4 and 5 show a schematic perspective view and an enlarged perspective view of a cross section of a main part of a robot joint device according to an embodiment.

A pair of fixed support parts 12 are formed at the tip of an arm 11 that becomes the robot body.
2, the outer part of the swing ring 13 is a double shaft outer shaft (swing shaft) 14 corresponding to the z-axis pin, and a drive shaft 15.
A z-axis drive motor 17 is mounted on the fixed support part 12, with one end of the outer shaft 14 fixed directly to the swing ring 13, and a driven spur gear 16 fitted to the other end. By engaging the pinions 18, the swing ring 13 can be driven to swing around the outer shaft 14 and the drive shaft 15.

A ring-shaped large bevel gear 20 that is rotatable concentrically with the swing ring 13 via a bearing 19 is attached to the inner circumference of the swing ring 13 as a ring-shaped power transmission member. A ring-shaped electromagnetic brake 2 is installed between the large bevel gear 20 and the large bevel gear 20.
1 is attached concentrically to the base end of the swing ring 13. This large bevel gear 20 meshes with a pinion bevel gear 23 that is fitted onto the tip of a double-shafted inner shaft 22 (drive shaft) that supports one end of the swing ring 13, and is connected to the inner shaft 22. Further, it is designed to be driven by an x-axis drive motor 24 installed on the fixed support part 12 of the arm 11. Further, the swing ring 13 has a pair of support parts 25 formed at positions perpendicular to the swing center axis z thereof, and a support shaft 26 rotatably supported by one of the support parts 25 and a disc-shaped The support bases 27 of the two are integrally connected, and the other support part 2
The support drive shaft 28 rotatably supported by the disk-shaped support base 2 is aligned with the support shaft 26.
7 is rotatably penetrated through the center.
The rotation axis x (support shaft 26 and support drive shaft 28) of the support base 27 and the swing center axis z are perpendicular to each other in one plane, and the center axis y of the arm 11 also intersects at this intersection. . A small bevel gear (support stand drive transmission mechanism) 29 that meshes with the large bevel gear 20 is integrally attached to the support shaft 26 that is integrated with the support stand 27. By driving the large bevel gear 20 with the x-axis drive motor 24, The support base 27 is rotated around the rotation axis x. A ring-shaped large bevel gear 31 that is rotatable concentrically with the swing ring 13 via a bearing 30 is attached to the outer circumference of the swing ring 13 as a ring-shaped power transmission member. The drive shaft 15, on which a part of the swing ring 13 is rotatably supported, is equipped with a γ-axis drive motor 32, and the drive shaft 15 has a small bevel gear 33 that meshes with the outer large bevel gear 31.
are integrally attached, and the large bevel gear 31 is rotated by a γ-axis drive motor 32. A small bevel gear (transmission shaft drive transmission mechanism) 34 that meshes with the large bevel gear 31 is integrated with the outer end of the support drive shaft 28 that passes through the disc-shaped support base 27 and is supported by the support part 25. A bevel gear 35 is integrally attached to the other end of the support drive shaft 28 that is attached and extends toward the center of the support stand 27, and the support stand 27 has a shaft 37 that is provided at one end with a bevel gear 36 that meshes with the bevel gear 35.
is supported, and a γ shaft 39 serving as a driving force transmission shaft is connected to this shaft 37 via an electromagnetic brake 38 supported on the support base 27 . Therefore, the above γ
The rotation of the large bevel gear 31 by the shaft drive motor 32 causes the small bevel gear 34, the support drive shaft 28, and the bevel gear 3 to rotate.
5, 36, shaft 37, and the γ-axis 3 via the brake 38.
9 is rotated around the γ axis.

The γ-axis 39 is connected to the wrist portion 40 and the like to form a robot.

The robot joint device configured as described above has two degrees of freedom on one plane, and the support base 27 can rotate around the central axis of oscillation z and the axis of rotation x via the oscillation ring 13. Moreover, the driving force can also be transmitted to the γ-axis 39 extending forward from the top of the support base 27.

First, rotation around the rotation axis x is achieved by driving the pinion bevel gear 23 via the double-shaft inner shaft 22 by the x-axis drive motor 24, and the large bevel gear 20 meshing with the pinion bevel gear 23.
By rotating the small bevel gear 29 fitted to the support shaft 26 that meshes with the large bevel gear 20, the support stand 27 integrated with the support shaft 26 is moved to the support shaft 26.
It rotates around the rotation axis x with .

On the other hand, the swinging around the z-axis, which is orthogonal to the rotation axis By driving the swing ring 13, the support base 27 is moved through the swing ring 13.
is swung around the swiveling center axis z.

In this way, the two x-axis drive motors 24 and the z-axis drive motor 17 installed on the arm 11 as the robot body rotate the support base 27 around the two rotation axes x and z arranged on one plane. Can be turned in any direction.

Furthermore, by driving the γ-axis drive motor 32, the outer large bevel gear 31 is rotated, and the γ-axis extends forward from the support base 27 through the aforementioned power transmission path.
Power is also transmitted to the shaft 39.

Note that the z-axis drive motor 17 is driven and the pinion 1
8. When giving the swinging ring 13 an angle β movement about the z-axis through the driven spur gear 16 and the outer shaft 14, the pinion bevel gear 23 at the tip of the inner shaft 22 and the small bevel gear on the drive shaft 15 33 is fixed to the outside world, the large bevel gears 20 and 31 each rotate according to the gear ratio to support the support base 27.
rotates about the x-axis by a certain angle, and the γ-axis 39 also rotates by a certain angle. However, when rotating the z-axis drive motor 17 to control the rotation of the swing ring 13 by the angle β, the angle of the support base 27 remains unchanged, and it is expected that the γ-axis 39 will not rotate. Therefore, in this case, it is necessary to control the x-axis drive motor 24 and the γ-axis drive motor 32 to restore the unnecessary rotation of the support base 27 and the γ-axis 39 caused by the rotation of the swing ring 13. . In addition, when the support stand 27 and the γ-axis 39 are fixed to the outside world, that is, the support stand 27 is fixed by the brake 21 fixing the swing ring 13 and the inner large bevel gear 20, and the γ-axis 39 is the brake 38
If the large bevel gear 2 is fixed to the outside world by
0 and 31 are fixed, the pinion bevel gear 23 and small bevel gear 33 that mesh with each rotate according to their respective gear ratios, but their rotational force only rotates the rotors of the motors 17 and 32. Then, the support base 27 and the γ-axis 39 do not rotate, and the z
It is maintained at its original position regardless of the rotation of the shaft drive motor 17. Furthermore, the electromagnetic brakes 21, 38
A potentiometer is provided instead of the motor 2, and the potentiometer adjusts the amount of rotation.
4 and 32 may be controlled.

In the above embodiment, a combination of bevel gears is used as the power transmission member drive mechanism, the support base drive transmission mechanism, and the transmission shaft drive transmission mechanism, but the gears may include crown gears, worm gears, spur gears, etc. They may be used in combination, and it is also possible to use not only gears but also chains and star wheels. Although the brakes 21 and 38 do not have to be electromagnetic brakes, control is further simplified by using electromagnetic brakes.

Further, in the embodiment described above, the x-axis and y-axis are provided in one plane and are orthogonal to each other, but the invention is not limited to this case, and the two axes may be arranged at a slight interval or may be other than orthogonal.

As described above in detail with the embodiments, according to the present invention, the joint device for the robot is rotatable around two intersecting axes in one plane or adjacently, so that the device can be made smaller. In addition to being able to scale, the drive source can be installed in the robot body, making it lighter in weight. Additionally, since there is no interference between the axes, the rotation range can be increased to nearly 180 degrees.
Therefore, it becomes easy to work in a narrow space, and control in any direction becomes easy. Furthermore, although it is a two-degree-of-freedom joint, power transmission through this joint and beyond can be achieved without using a universal joint.

[Brief explanation of drawings]

Figure 1 is a perspective view of a conventional robot joint device.
Figure 2 is an explanatory diagram showing the movement of the robot in two degrees of freedom, Figure 3 is a schematic perspective view of a conventional joint device, and Figure 4 is a schematic perspective view of a conventional joint device.
5 and 5 show an embodiment of the robot joint device of the present invention, FIG. 4 is a schematic perspective view, and FIG. 5 is an enlarged perspective view of the main parts. In the drawing, 11 is an arm, 12 is a fixed support part, 1
3 is a swing ring, 14 is an outer shaft, 15 is a drive shaft, 1
7 is a z-axis drive motor, 19 is a bearing, 20 is a large bevel gear, 21 is an electromagnetic brake, 22 is an inner shaft, 23 is a pinion bevel gear, 24 is an x-axis drive motor, 26 is a support shaft, 27 is a disc shape , 28 is a support drive shaft, 29 is a small bevel gear, 30 is a bearing, 31 is a large bevel gear, 32 is a γ-axis drive motor, 33 and 34 are small bevel gears, 35 and 36 are bevel gears, 38 is a electromagnetic brake,
39 is the γ axis.

Claims (1)

[Scope of utility model registration request] A support base that rotatably supports a support drive shaft and a drive force transmission shaft that intersects with the support drive shaft and transmits rotational force from the support drive shaft; and a swing ring that rotatably supports the support base via a support shaft coaxial with the support drive shaft, and a swing ring that swings freely via a swing shaft that intersects with the support shaft. A robot body to be supported, a ring drive mechanism provided on the robot body to swing the swing ring around the swing axis, and a ring drive mechanism that swings the swing ring around an axis intersecting the support shaft and the swing axis. two ring-shaped power transmission members rotatably fitted to the rocking ring on the inner and outer peripheral sides of the robot body; two power transmission member drive mechanisms that rotate these two power transmission members independently via a drive shaft forming a A support drive transmission mechanism that rotates the support shaft around the support shaft; and a transmission shaft drive transmission mechanism that is provided between the other power transmission member and the support drive shaft and rotates the support drive shaft. Robot joint device.