JPS60172492A - Arm structure of industrial robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a robot arm, and relates to improving the strength of a resin-molded arm with reduced weight and ensuring accuracy against changes in ambient conditions.

[Background of the invention]

A conventional industrial robot will be explained with reference to FIG.

1 is a main body, 2 is a first arm, 3 is a first arm rotation axis, 4 is a second arm, and 5 is a second arm rotation axis. The arms of conventional robots are almost all made of metal molded bags such as aluminum tie-casting, or processed metals such as steel and aluminum, and the arms involved are heavy and large, so a large arm driving force is required. However, the arm drive motor 9 output has the disadvantage of being large and expensive, and the metal arm is also limited in shape due to manufacturing, and since the tonne 11 (is large), arm support such as the main body 1 and the rotating shaft 3.5 is required. This had the disadvantage of making the structure more robust and making the device as a whole more expensive.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a robot that is lightweight, has a strong arm strength, reduces arm driving force, and downsizes the drive motor, and is thus inexpensive.

[-Summary of the invention]

11 In an industrial robot comprising a first arm (2) rotatably mounted on a main body (1), and a second arm (4) rotatably protruding from the first arm (2), The arms (2) and (4) are molded of resin into the shape of a gutter or boat with flanges arranged vertically on the bottom and around the bottom, and a first arm rotation shaft (3) is formed on the bottom of the first arm (2). ) and the metal plate (13) connecting the second arm rotation shaft (5).
a) Or an arm structure for an industrial robot, characterized in that it is formed by integrally molding a fiber-reinforced core body (13b) with an insert.

2. Foamed resin (15) on the inner surface of resin arms (2) and (4)
Surface side [Claim 1 formed by multilayer molding with rigid resin or fiber-reinforced resin (14) disposed
The arm structure of the industrial robot described in Section 1.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. 2 is a first arm that is rotatably mounted on the main body 1, 4 is a second arm that is parallel to the first arm 2 and rotatably protrudes, and 6 is a second arm.
The third arm is slidable perpendicularly to the arm 4, and is connected to a tool gripping shaft 7 that can be pivoted and gripped. Further, 9 is a second arm driving motor built into the first arm 2, and the second arm driving pulley 10 is coaxially fixed thereto, and 5 is the second arm rotating shaft, which drives the second arm driven pulley 11 at 1+! 11, both pulleys]
0.11 are connected via a transmission belt 12.

In the robot of this embodiment, the first arm 2 and the second arm 4 are formed into a boat shape with reinforcing flanges arranged on the bottom and around the bottom, and a U-shaped cross section is formed on the bottom.

A thin metal plate 13 of extremely small specific gravity such as aluminum or magnesium alloy is arranged, and carbon fiber reinforced resin 14 so-called CFRP or glass fiber reinforced resin so-called GFRP is arranged on the front side of the arm 2.4, and on the inner side. , the foaming ratio is several times higher than that of the fiber reinforced resin base + A
quality foaming (b) place the fat and iii + mark the thin metal base 1
3 is formed by insert molding, and the fiber-reinforced resin 14 and foamed resin 15 are integrally molded, the moment of inertia of the arm 2.4 is greatly reduced, and its strength can be extremely increased, making it practical. The necessary strength can be secured. in general,
The linear expansion coefficient of aluminum alloy and magnesium alloy is 2×1
0"'/℃, and for commonly used glass fiber reinforced resins, it is 6 to 8 x lO"''/℃, so high performance robots that require extremely high precision are affected by dimensional changes due to temperature changes in the resin arms. According to the embodiment of the present invention, the metal plate 13 is insert-molded on the bottom surface of the arm 2 in a manner corresponding to the distance from the first arm rotation axis 3 to the second arm rotation axis 5. The distance between the rotating axes can be maintained at the same viscosity as the metal arms of high-performance type robots, and the weight of the resin arms 2 and 4 as a whole can be significantly reduced, resulting in lower output and smaller size of the arm drive motors 8 and 9. This has the effect of making it possible to construct the device at a low cost, and also has the effect of simplifying the arm support device.Furthermore, according to this embodiment, since foamed resin is used for the inner surface of the vagina, thin metal By absorbing the increased weight of the plate, the weight of the entire arm remains almost the same as when the metal plate 13 is not used.

On the other hand, fibers such as organic polyaramid fibers and carbon fibers made by carbonizing polyaramid fibers have a linear expansion coefficient of 1/2 that of metals, minus 2 x 10"/°C, and are more resistant to temperature rises. According to this embodiment, it is known that the robot resin arm 2.4 has a negative expansion or contraction property, and also has extremely strong strength. When the polyaramid fiber woven fabric, carbon fiber woven fabric, or other reinforcing fiber woven fabric is inserted as a reinforcing core body and integrally molded, the metal plate 13 is inserted and integrally formed according to the distance. Almost the same effect as when formed by

[Effects of the Invention] According to the present invention, the arms 2.4 of the robot are integrally molded with resin in the shape of a gutter or boat with a flange provided vertically around the bottom surface, corresponding to the distance between the rotational axes of the bottom surface of the arm. Then, a metal plate 13 having a thin U-shape or U-shape cross-sectional shape is inserted and integrally formed, so the weight is significantly reduced compared to the metal arm seen in the conventional example. As a result, it is possible to downsize and reduce the cost of the arm drive motor.Furthermore, there is no need to make the arm support structure such as the robot body or rotation axis robust, making it simpler and making the entire robot cheaper. It has the effect of being able to be configured, and the effects of changes in the robot's ambient temperature, gripping front stop, and arm molding specifications can be reduced to about 1/3 of the total resin arm, which requires extremely high precision. It is effective in ensuring the performance of this type of robot arm.

[Brief explanation of drawings]

FIG. 1 is a side view of a conventional robot, FIG. 2 is a side view of a robot according to an embodiment of the present invention, and FIG. 3 is a schematic explanatory diagram of a right side sectional view of FIG. DESCRIPTION OF SYMBOLS 1... Main body, 2... First arm, 3... First arm rotation axis, 4... Second arm, 5... Second arm rotation axis, 6... Third arm, 7... Tool gripping shaft, 8... First arm drive motor, 9... Second arm drive motor, 10... Second arm driving boob IJ-111... Second arm driven boob IJ- 112
... Transmission belt, 13... Metal plate, 14... Fiber reinforced resin, 15... Foamed resin. Figure $1 Figure $3

Claims (1)

[Claims] 1. A first arm (2) is rotatably mounted on the main body (1), and a second arm (4) is rotatably protruded from the first arm (2). In an industrial robot, the arms (2) and (4) are molded from resin into a gutter-like or ship-like shape with flanges arranged vertically on the bottom and around the bottom, and the bottom of the first arm (2) is molded with resin. A metal plate (13) connecting the first arm rotation shaft (3) and the second arm rotation shaft (5)
a) Or an arm structure for an industrial robot, characterized in that it is formed by integrally molding a fiber-reinforced core body (13b) with an insert. 2. Foamed resin (15) on the inner surface of resin arms (2) and (4)
The arm structure of an industrial robot according to claim 1, which is formed by multilayer molding with a rigid resin or fiber-reinforced resin (14) disposed on the surface side.