JPS6260236B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flexible arm used in, for example, industrial robots.

Prior Art Most of the arms used in industrial robots employ link mechanisms. This link mechanism is not suitable when the work space is narrow and there are obstacles in front. In order to overcome this drawback, an arm was constructed by connecting a large number of discs with varying thicknesses, and by rotating these discs, the arm could be bent in any direction (Japanese Patent Laid-Open No. 58 - Publication No. 59785)
and multi-jointed arm (Japanese Patent Application Laid-open No. 129687/1987)
is proposed.

Problems to be Solved by the Invention However, although the above-mentioned conventional arm can be bent in any direction, it cannot be expanded and contracted at the same time, which poses a problem when attempting to automate complex processes. Ta.

Means for Solving the Problems In order to solve the above problems, the flexible arm of the present invention includes three rod-shaped bodies arranged radially at 120° intervals in a first plane and each having one end connected to the other. , a sliding body held by each rod-shaped body so as to be slidable in its axial direction, and one end of which is pivotally supported by the other end of each of the rod-shaped bodies, and within a second plane perpendicular to the first plane. The first and second swinging links, which are swingable, and each first swinging link and the corresponding sliding body are connected in one space separated by the first swinging link and the first plane. A first connecting link that guides, and a second connecting link that connects each second swinging link and its corresponding sliding body and guides the second swinging link in the other space separated by the first plane. It is constructed by connecting a plurality of basic units consisting of, and each first swinging link of one basic unit and each second swinging link of the other basic unit is a connecting part of the basic units. The other end of the link is connected to the link via a spherical bearing. In the above configuration, if each set of the first and second swing links provided at one end of the rod-shaped body arranged at 120° intervals is swung at the same swing angle, the flexible arm will expand and contract. Further, by swinging each set of the first and second swing links at different swing angles, the flexible arm bends in a predetermined direction.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 8. 1 is a flexible arm device,
A plurality of basic units 3 (two in this embodiment) forming the flexible arm 2, a first end unit 4 connected to one end of the basic unit 3, and the other end of the basic unit 3. a second end unit 5 connected to the side;
and a drive device 6 that bends the flexible arm 2 in any direction via the end unit 5 and extends and contracts the flexible arm 2. Hereinafter, the flexible arm 2, the first end unit 4, the fourth end unit 5, and the drive device 6 will be explained in this order.

As shown in FIGS. 1 to 5, the flexible arm 2 is composed of a plurality of basic units 3. As shown in FIGS. This basic unit body 3 consists of three pieces arranged radially at 120° intervals in a first plane (for example, a horizontal plane in FIG. 1), and each of which has one end connected to the other via a cylindrical connecting member 7. A rod-shaped body 8, a sliding body (for example, a linear bearing) externally fitted and held on each of these rod-shaped bodies 8 so as to be slidable in the axial direction thereof, and a connecting pin (a third a first plane which is pivotably supported via a second plane (having an axis perpendicular to the rod-shaped body 8 in one plane) and swingable within a second plane (vertical plane in FIG. 1) perpendicular to the first plane; and second swing links 11, 12,
The middle part of each first swing link 11 and the corresponding sliding body 9 are connected to each other so that the first swing link 11 is
A first connecting link 14 that guides its swinging within one space (the upper space in FIG. 1) divided by a plane, and a corresponding sliding body 9 in the middle of each second swinging link 12. and a second connecting link 15 that connects the second swing link 12 with the first plane and guides the swing of the second swing link 12 in the other space (the lower space in FIG. 1) separated by the first plane. There is. The lengths of each rod-shaped body 8, the lengths of each swinging link 11, 12, and the lengths of each connecting link 14, 15 are made equal, and the lengths of each swinging link 11, 15 are equal. 12 and each connecting link 14, 15 are provided alternately on both sides of the rod-shaped body 8, and the end of each connecting link 14, 15 is
Mounting pins 1 parallel to the connecting links 10, respectively.
6 to the other party. The flexible arm 2 is made up of two of the basic unit bodies 3 connected together, and a spherical bearing 17 is used at the connecting portion. That is, a spherical bearing is connected to the other end (upper end) of the first swing link 11 of one (for example, lower) basic unit 3A via a mounting pin (having an axis parallel to the connecting pin 10). 1
At the same time, a holding box 19 for holding the spherical bearing 17 is attached to the other end (lower end) of the second swing link 12 of the other (for example, upper) basic unit 3B. Next, the first and second single unit bodies 4 and 5 will be explained. As shown in FIG. 1, the first end unit 4 is for connecting the flexible arm 2 and the operation part (for example, the wrist part) of the robot, and similarly to the basic unit 3, the first end unit 4 is connected radially. Three connecting rods 2
0 and a connecting swing link 21 similar to the second swing link 12, and a first swing link of the basic unit 3B above the connecting swing link 21 and the flexible arm 2. 11 are also connected via the same spherical bearing 17 as above. Further, as shown in FIGS. 6 and 7, the second end unit 5 connects the flexible arm 2 and its drive device 6, and connects the first swing link 11 of the basic unit 3. Similar drive swing link 2
One end of 2 is placed on the frame 2 in the same arrangement as the basic unit 3.
3 via support pins 24,
The other end is connected to the second swing link 12 of the basic unit 3A below the flexible arm 2 via the same spherical bearing 17 as described above.

Next, explaining the drive device 6, as shown in FIGS. 6 and 7, on the lower surface of the pedestal 23 at the position corresponding to each of the drive swing links 22,
A servo motor 25 with a speed reducer is attached to each, and one end of a drive link 26 is connected to the output shaft 25a of the drive link 26.
The other end and the corresponding drive swing link 22
is connected to the intermediate portion of the connector via a connecting link 27. Furthermore, the output shaft 2 of the servo motor 25
The rotation angle of 5a remains the same as the driving swing link 22.
The driving swing link 22 and the drive link 26 are parallel to each other, and the connecting link 27 is parallel to the straight line connecting the fulcrum of the drive swing link 22 and the axis of the output shaft 25a. (parallel link mechanism).

Therefore, when the three servo motors 25 disposed on the lower surface of the pedestal 23 are rotated at the same rotation angle to swing each driving swing link 22 downward, for example, the third servo motor 25 of the lower basic unit 3B is rotated. The second swing link 12 follows, and at the same time the angle (α) between the rod-shaped body 8 and this second swing link 12 becomes smaller.
The sliding body 9 moves inward, and the angle (β) between the rod-shaped body 8 and the first swing link 11 also becomes smaller (of course, α=β). Therefore, it will shrink overall. Furthermore, if the rotation angle of, for example, one of the three servo motors 25 is increased, the drive swing link 22 connected to that servo motor 25 will tilt more than the other drive swing links 22. Each of the swing links 11, 12, and 21 connected to the driving swing link 22 also tilts significantly, so that the flexible arm 2 as a whole expands and contracts as well as bends in that direction. In addition,
A spherical bearing 1 is installed at the connecting part of each unit body 3, 4, and 5.
7, the flexible arm 2 can freely tilt. In addition, by appropriately selecting the rotation angles of the three servo motors 25,
The length of the flexible arm 2 and its bending direction can be freely adjusted. In addition, Fig. 8 shows
It is a schematic perspective view when the flexible arm 2 is bent in a certain direction.

Effects of the Invention According to the configuration of the present invention described above, the flexible arm includes three rod-shaped bodies arranged at 120° intervals;
Since a plurality of basic units consisting of first and second swing links that swing in opposite directions are connected to each end of each of these rod-shaped bodies, the first and second swing links are connected to each other.
By swinging each set of swing links at the same angle, the spacing between the rod-like bodies, that is, the flexible arms, can be expanded and contracted. In addition, since a spherical bearing is interposed in the connecting portion between the basic unit bodies, if each set of the first and second swing links is swung at different angles, the structure formed by each rod-shaped body can be adjusted. The first planes can be inclined with respect to each other, so that the flexible arm can be extended and contracted and also inclined in any direction.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a schematic overall configuration diagram, FIG. 2 is a sectional view of a connecting portion of a rod-like body, FIG. 3 is a view taken along the - arrow in FIG. 2, and FIG. is a sectional view of the swing link, FIG. 5 is a sectional view of the connecting link part, FIG. 6 is a partially cutaway front view of the drive unit, FIG. 7 is a view taken from the - arrow in FIG. 6, and FIG. It is a schematic perspective view showing operation. 2... Flexible arm, 3, 3A, 3B... Basic unit body, 5... Second end unit body, 8... Rod-shaped body, 9
...Sliding body, 11...First swing link, 12...Second swing link, 14...First connection link, 15...Second connection link, 17...Spherical bearing.

Claims (1)

[Claims] 1. Three rod-shaped bodies arranged radially at 120° intervals in a first plane and connected to each other at one end, and a sliding body held by each rod-shaped body so as to be slidable in its axial direction. , first and second swing links, each of which has one end pivotally supported by the other end of each of the rod-shaped bodies and is swingable in a second plane perpendicular to the first plane; and each first swing link. and a sliding body corresponding thereto, and a first connecting link that guides the first swinging link in one space partitioned by the first plane, and each second swinging link and the sliding body corresponding thereto. and a second connecting link that connects and guides the second swing link in the other space separated by the first plane,
Further, the other ends of each of the first swinging links of one basic unit and each of the second swinging links of the other basic unit, which are the connecting portions of the basic units, are connected via a spherical bearing. A flexible arm characterized by: