JPH0347996B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flexible arm device used, for example, in 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 number of discs with varying thicknesses, and by rotating the discs, the arm could be bent in any direction (Japanese Patent Laid-Open No. 58 −59785)
and multi-jointed arm (Japanese Unexamined Patent Publication 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 device of the present invention has three first to third supports each including each vertex of an equilateral triangle arranged in an overlapping manner, and At each apex position of the second support, a pair of swing links are provided which are swingable in a second plane perpendicular to the first plane including the second support, and the first and third supports A swinging link that can swing freely within a second plane perpendicular to the first plane containing the respective support is provided at each vertex of the support, and one swinging link of the second support and the first support The swing link, the other swing link of the second support body, and the swing link of the third support body are connected through spherical bearings, and the link passes through each vertex of the second support body and the center of the triangle thereof. A screw shaft is supported on the shaft so as to be rotatable around its axis, and a movable body is screwed onto each of these screw shafts, and a swing link supported at each vertex of each of these movable bodies and the second support body is attached. with the middle part,
The screw shafts are connected to each other through connecting links, and the screw shafts are rotated separately to connect the second screw shaft through each moving body.
A rotary drive device is provided for swinging each pair of swing links of the support body in mutually opposite directions.

Effect In the above configuration, if the rotary drive device rotates each screw shaft to move the movable body, each swing link swings at the same angle and the spacing between each support body changes, so the overall expands and contracts as In addition, by adjusting the rotation amount of each screw shaft and making the swing angle of each set of swing links corresponding to each vertex different, the supports will have an inclination angle with each other.
The whole can be tilted in any direction.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the drawings. In FIG. 1, reference numeral 1 denotes a flexible arm device, which is composed of a flexible arm 3 configured by connecting one or more basic unit bodies 2, and a rotation drive device 4 for extending, contracting and tilting this flexible arm 3. ing. In this embodiment, a case will be described in which the flexible arm 3 is composed of a set of basic unit bodies 2.

First, the basic unit body 2 will be explained based on FIGS. 2 to 4. Reference numerals 5 to 7 denote first to third supports, which are composed of an annular plate 8 having a through hole 8a in the center and a circular flange plate 9 vertically disposed around the annular plate 8;
A support shaft 10 is provided at a position corresponding to each vertex of an equilateral triangle of each circular flange plate 9 in the tangential direction of the circle passing through each vertex. In addition, the above
The third supports 5 to 7 are arranged so as to be sequentially stacked from the bottom to the top. A pair of swing links 11 and 12 are rotatably supported on both sides of each support shaft 10 of the second support body 6 located in the middle, and the first and third support bodies 5, 7
One swing link 13, 1 is attached to each support shaft 10 of
4 are supported rotatably around their respective axes. Therefore, each of the swing links 11 to 14 is swingable within a second plane perpendicular to the first plane that includes each vertex of an equilateral triangle. One (lower) swing link 11 of the second support body 6
and the corresponding swing link 1 of the first support body 5
3, and each swing link 12 on the other (upper side) of the second support 6 and the corresponding swing link 14 of the third support 7 are connected via spherical bearings 15, respectively. . 16 is a bearing 1 along an axis passing through each vertex of the second support 6 and the center of the triangle.
A screw shaft is rotatably supported on the annular body 8 via 7A and 17B, and a movable body 19 is screwed into this screw shaft 16 via a nut body 18, and the movable body 19 and the second support The intermediate portions of a pair of swing links 11 and 12 provided on the body 6 are connected via connection links 20 and 21, respectively. In addition, the size of each of the supports 5 to 7, the length of each of the swing links 11 to 14, and the connecting link 2
The lengths of the 0 and 21 comrades are equal, and the swing links 11 to 14 and the connecting links 20 and 21 are provided alternately on both sides of the screw shaft 16, and the ends of the connecting links 20 and 21 are arranged alternately on both sides of the screw shaft 16. The department is
Each is connected to the other by a mounting pin 22 parallel to the support shaft 10. Further, 23 is a guide rod for guiding the movement of the moving body 19. Reference numeral 24 denotes a frame attached to the lower part of the first support body 5, which supports the basic unit body 2. Although not shown, the wrist of the robot is connected to the third support 7.

Next, the rotary drive device 4 will be explained based on FIGS. 1 and 2. This rotary drive device 4 includes a first bevel gear 25 attached to the inner end of the screw shaft 16, a support member 26 provided at an upper position inside the central through hole 8a of the second support body 6, and Part 2
6 is supported via bearings 27A and 27B in a direction perpendicular to the first plane, and the first bevel gear 25 is attached to the rotating shaft 28 and
The second bevel gear 29 is meshed with the second bevel gear 29, and the servo motor 31 rotates the rotating shaft 28 via a connecting member 30 which is disposed within the central through hole 8a of each annular body 8 and is extendable and retractable. has been done. Of course, three rotary drive devices 4 are arranged corresponding to each screw shaft 16. The connecting member 30
The connecting rod 34 has one end connected to the servo motor 31 via a universal joint 32 and pins 33 protruding from both sides of the other end, and a connecting rod 34 whose one end is connected to the rotating shaft 2 via the universal joint 32.
8, the other end is sized to fit the connecting rod 34, and the pin 3 of the connecting rod 34 is connected to the pin 3 of the connecting rod 34.
3 and a connecting tube 35 in which a groove (not shown) is formed to allow movement of the connecting tube 3 only in the insertion direction. Further, the servo motor 31 is provided, for example, on a pedestal 24 that supports the basic unit 2.

Therefore, in the above configuration, when the three servo motors 31 arranged on the pedestal 24 are rotated at the same rotation angle to move the movable body 19 outward, for example, the swing link 11 of the second support body 6 ,12
swings outward and this swing link 11,1
The respective swing links 13, 14 of the first and third supports 5, 7 connected to the base unit 2 also follow and swing outward, so that the basic unit 2 is extended as a whole. Of course, if the movable body 19 is moved inward, it will shrink as a whole. Also, for example, one of the three servo motors 31 may have a smaller rotation angle than the other servo motors 31 to reduce the rotation angle of the moving body 1.
When the amount of movement of 9 is decreased, the basic unit 2 is tilted in that direction. Furthermore, by appropriately selecting the rotation angles of the three servo motors 31, the length of the basic unit 2 and its tilting direction can be freely adjusted.
Note that, as shown in FIG. 1, the swing angle α of each swing link corresponding to each vertex with respect to the support body is equal.

By the way, in the above embodiment, the case where there is one basic unit body 2 has been explained, but normally the fifth
As shown in the figure, two or more basic units 2A, 2
B are sequentially connected via the support shaft 10, and
The corresponding rotating shafts 28 of each basic unit body 2A, 2B are connected to each other via a connecting member 30.
Furthermore, as shown in FIG. 6, by attaching a servo motor 31 to each basic unit 2 and tilting each of them separately, it is possible to meander.

Effects of the Invention According to the configuration of the present invention described above, the three first to third supports each including each vertex of an equilateral triangle are connected via the swinging link, and the swinging link corresponding to each of these vertices is connected. Since a rotary drive device is provided to separately swing the sets of links via screw shafts, by swinging each set of swing links at the same angle using the rotary drive device, the distance between each support can be changed. That is, it can be expanded and contracted. In addition, since a spherical bearing is interposed in the connection between each swinging link, by swinging each set of swinging links at different angles, the supports can be tilted relative to each other. It can also be tilted in any direction at the same time as the expansion and contraction described above.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a schematic diagram of the overall configuration, FIG. 2 is an enlarged sectional view of main parts, and FIG. 3 is a view taken along the - arrow in FIG. 2. , FIG. 4 is a view taken along the - arrow in FIG. 2, and FIGS. 5 and 6 are diagrams showing the overall configuration of other embodiments. DESCRIPTION OF SYMBOLS 1... Flexible arm device, 2... Basic unit, 3... Flexible arm, 4... Rotation drive device, 5... First support body, 6... Second support body,
7...Third support body, 10...Support shaft, 11-14
... Swinging link, 15 ... Spherical bearing, 16 ... Screw shaft, 19 ... Moving body, 20, 21 ... Connection link, 25 ... First bevel gear, 28 ... Rotating shaft, 2
9...Second bevel gear, 30...Connection member, 31...
...Servo motor, 34...Connection rod, 35...Connection cylinder.

Claims (1)

[Claims] 1. Three first lines each containing each vertex of an equilateral triangle.
- The third supports are arranged so as to overlap each other, and at each vertex position of the second support located in the middle, the second support is arranged so as to overlap.
A pair of swinging links that are swingable in a second plane perpendicular to a first plane that includes the supports are provided, and the first plane that includes the respective supports is provided at each apex of the first and third supports. A swing link that is swingable in a second plane perpendicular to is provided, and one swing link of the second support, a swing link of the first support, and the other swing link of the second support. and the swing link of the third support are connected through spherical bearings, and a screw shaft is freely rotatable about the axis on an axis passing through each vertex of the second support and the center of the triangle. At the same time, a movable body is screwed onto each of these screw shafts, and each of these movable bodies and the intermediate portion of the swing link supported at each apex of the second support body are connected via a connecting link, respectively. The flexible arm device is further provided with a rotational drive device that rotates each of the screw shafts separately and swings each pair of swinging links of the second support in opposite directions via each movable body. .