JPS6352989A - Motor robot - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electric robot, and more particularly to an electric robot having an explosion-proof structure suitable for use in a flammable atmosphere.

BACKGROUND OF THE INVENTION Various types of hydraulically driven industrial robots have been proposed in the past, but electric robots are being developed to replace hydraulically driven robots.

Since an electric robot has a structure in which each movable part is driven by a motor, it is necessary to have an explosion-proof structure when using the robot in a highly flammable atmosphere, for example.

For example, in electric painting robots that spray flammable paint, it is being considered to have an internal pressure explosion-proof structure for electrical systems that tend to generate sparks.

Therefore, the cables that supply power to the terminal box and the cables that connect the terminal box and each motor are inserted into a tube made of honeysuckle + M construction that is supplied with protective gas at a predetermined pressure inside, and is explosion-proof. The structure is such that if the gas inside the tube leaks and the pressure drops, the power supply is cut off. In addition, in the electric robot of this scale, for example, a plurality of motors for driving each movable part are installed on the base, and a terminal box to which an iri source is supplied from the outside is installed inside the base. ing. Therefore, a plurality of cables connecting the terminal box and each motor are inserted into the rotating part that rotatably supports the movable part on the base.

Problems to be Solved by the Invention However, in the above-mentioned electric robot, each cable is
Since each duplex is inserted into the tube one by one, if multiple duplexes are bundled together within the rotating part of the base, their outer circumference will become large.For example, if there are dimensional restrictions on the rotating part or the number of cables increases. There is a problem in that the outer diameter becomes too large depending on the state in which the tubes are assembled, making it difficult to pass each cable through the inside of the rotating part. Furthermore, the electric robot described above has a problem in that when the rotary base on the base is rotated, twisting force is applied to each tube, resulting in poor durability of the tubes.

Therefore, an object of the present invention is to provide an electric robot that solves the above problems.

Means and Action for Solving the Problems The present invention provides a plurality of movable parts on the upper part of the base, a plurality of motors for driving the movable parts, and A terminal box for supplying power to a plurality of motors is provided, and an airtight chamber is provided in the rotating part of the base, one end of which communicates with the terminal box and where protective gas at a predetermined pressure is supplied,
The cables are connected to the motor from the other end of the viewing chamber through the viewing chamber, and the plurality of cables are collectively constructed within the rotating part to form an internal pressure explosion-proof structure, reducing the outer circumference of the aggregate of the plurality of cables and reducing the This is designed to reduce the twisting force acting on the cable.

Embodiment FIGS. 1 to 3 show an embodiment of the electric robot according to the present invention. In each figure, a rotary base 2 is rotatably provided above a base 1, and a branch office 3 is provided on the rotary base 2. Also, the support column 3 is connected to the bracket 2 of the rotating base 2.
a and 2b, and rotatably supports an arm 4 extending in the horizontal direction at its upper end.

Further, 5 is a motor unit for driving the rotation base 2 attached to the base 1, 6 is a motor unit for driving the column 3 attached to the rotation base 2, and 7 is a motor for driving the arm 4 attached to the rotation base 2. It is a unit. Note that the driving force of the motor unit 7 is transmitted to the rear end of the arm 4 via the link 11 to drive the arm 4. Furthermore, at the rear end of the arm 4, there is a wrist drive motor unit i that drives the wrist mechanism attached to the tip of the arm 4.
-8, 9, and 10 are arranged, respectively.

Each motor unit 5=10 has a structure in which an electric motor serving as a driving source, and its accessories such as a deceleration gate structure and a rotation speed detection sensor are housed in a sealed container B.

Further, a terminal box 12 is provided inside the base 1. As shown in FIG. 4, the terminal box 12 has a gasket (not shown) interposed between the box body 12A and the lid 12B, and the box body 12A and the cable passage area are sealed, so that the inside is sealed. It has a sealed structure.

Further, as shown in FIG. 3.4.5, an opening 12a is provided on the rear surface of the terminal box 12 for allowing a plurality of cables to exit. 13 is a bellows-shaped communication tube, one end of which is connected to the terminal box 12.
The (l!! end is connected to the insertion port 14a of the duct 14).

This duct 14 is provided at the bottom of the base 1, and has a top opening 14b. 15S is a cylindrical duct that is inserted inside the cylindrical rotating part 16, and its lower end is inserted into the opening 14b of the duct 14 below. Further, a duct 17 for connecting a tube that communicates with the duct 15 is provided at the upper end of the duct 15. 18 is an O-ring,
The space between the ducts 14 and 15 is airtightly sealed. These ducts 14, 15, and 17 form one airtight chamber that is connected in communication, and a terminal box 1 is inserted into the inside through a communication pipe 13.
A protective gas supplied within 2 is introduced. For this reason, the inside of the ducts 14, 15, and 17 has an internal pressure explosion-proof structure.

Note that the upper part of the rotating part 16 is fixed to the rotating base 2, and the outer periphery of the rotating part 16 is fixed to the bearing 19a of the base 1.

It is rotatably supported by 19b. Further, the duct 17 is fixed to the rotating base 2, and the duct 15, which is integrated with the duct 17, rotates as the rotating base 2 rotates. In addition, the duct 17 has a tube 20 as shown in FIG.
are connected in a sealed manner, and the other end of the tube 20 is connected in a sealed manner to each container 8 of each motor unit 6.7.8.9.10. Also, inside the tube 2o, the cable 21 from the terminal box 12 is connected to the communication pipe 13 and the duct 1.
The terminal box 12 and each motor unit 6.7°, 8.9.10 are connected by a cable 21.

Furthermore, as mentioned above? ! The internal space of the communication tube 13 and the duct 14, 15, 17 through which the two cables 21 are inserted is sufficiently wider than the outer circumference of the bundle of the plurality of cables 21. Therefore, the plurality of cables 21 are inserted in the communication pipe 13 and the duct 14.15° 17 in a slightly slack state, so that when the rotating base 2 rotates, no strong torsion force is applied to each cable 21. This is advantageous in terms of the durability of the cable 21.

Also, although the outer circumferential dimension changes somewhat depending on the state of collection of the plurality of cables 21, there is sufficient space within the duct 15, so even if the number of cables 21 increases, the duct 15
performed without increasing the size. That is, since the number of cables 21 can be increased without changing the outer diameters of the ducts 1 to 15 and the rotating part 16 of the rotating base 2, when designing the rotating part 16, the outer diameter of the duct 15 is not reduced by λ, 11, and the design of the rotating part is reduced. The degree of freedom in training is improved.

In addition, by passing multiple cables 21 all at once into the airtight duct 14, 15, 17, it is possible to more easily realize an internal pressure explosion-proof structure in the rotating part, and the cables 21 can be duplexed one by one. It is cheaper to put the actual vine back on than it is to cover it and create an internal pressure explosion-proof structure.

Further, a duplex 23 in which a movable cable 22 is disposed and a duplex 25 in which a signal cable 24 is disposed are connected to the terminal box 12 in a close 1:1 state. The tubes 23-25 are flexible, and gas is allowed to flow between them and the cables 22-24. ?
A large gap is formed. The proximal ends of these tubes 23, 25 are connected to a source of non-flammable protective gas (eg, inert gas or compressed air).

The dynamic cable 22 is electrically connected to a terminal block 26 in the terminal box 12, and the signal cable 24 is connected to the terminal block 26 in the terminal box 12.
It is electrically connected to a terminal block 27 and a connector 28 inside. Further, the other end of the cable 21 connected to each motor unit 6, 7, 8, 9° 10 is connected to the connector 28.

30 is a Senno j cable that electrically connects the terminal block 26 and each of the motor units 5 to 10; 31 is the terminal block 2;
7 and each motor unit 5 to 10 electrically. Like the cable 21, these cables 30.31 also have their outer peripheries covered by tubes 32.33.

Duplexes 20, 32, and 33 are flexible tubes coated with nylon that are generally used for air feeding, and inside are cables 2, similar to the tubes 23 and 25.
1, 30, and 31, a gap large enough to allow gas to flow is formed between the two.

A manifold 40 is provided integrally with the terminal box main body 12A at a portion of the tubes 32, 33 connected to the terminal box 12. Inside the manifold 40 is a boat 34.
A plurality of (12 in this case) are provided independently. As shown in FIG. 5, the boat 34 includes a main path 34A extending in one direction through which the cable is inserted, and a sub-path 34B extending orthogonally thereto. These boats 34 are connected to the tubes 32 and 33 through plugs 35, and communicated with the insides of the tubes 32 and 33, respectively. In addition, an inner brim 36 is located inside the branching part of the main path 34A of the boat 34 and the secondary path 34B.
is formed.

Plug 3 screwed to inner collar 36 and boat 34
A packing 38 is sandwiched between the cables 30 and 7 with cables 30 and 31 inserted therethrough.

Each boat 34 is connected to the terminal box 12 by this packing 38.
It is connected to the inner space.

Furthermore, pressure sensors 39 are installed in a sealed manner at the outer ends of the secondary passages 34B of the boat. This pressure sensor 39 is connected to a controller (not shown), and the boat 3
If the internal pressure in any of the four cases falls below a predetermined level, this is detected and the power source for operating the mouth pot is cut off.

Next, the operation of the explosion-proof structure having the above configuration will be explained. Air supplied into the terminal box 12 from a compressed air supply source (not shown) via the duplexes 23, 25 flows into the ducts 1 to 14 from the opening 12a of the terminal box 12 via the communicating pipe 13. Terminal box 12, communication pipe 13, duct 14.15.17
Since each of the terminal boxes 15 and 17 has an airtight structure, the protective gas from the terminal box 12 fills the ducts 15 and 17 from the duct 14,
It is guided through the tube 20 into each motor unit 5-10. The air guided to these motor units 5 to 10 is further passed through tubes 32 and 33 to the boat 3 of the manifold 40 that is integrally provided in the terminal box 12.
4. That is, the tube 20 is connected to the duct 17
The tubes 32, 33 function as outgoing channels that supply air from the motor units 5 to 10 to the motor units 5 to 10, and the tubes 32 and 33 function as return channels that return air from the motor units 5 to 10 to the boat 34.

In the air flow system described above, there is some air leakage from the tube connection, terminal box 12, or motor unit storage container B, but the leakage is replenished from the air supply source, and the entire flow system is always required. kept under pressure.

Therefore, under normal conditions, i.e., when the pressure in the port 1-34 is above a predetermined value, it is guaranteed that the pressure in all the air flow systems is above the predetermined value (the boat 34 is located at the end of the air flow system). The flammable gas (the pressure in this area is the lowest) will not enter into the motor units 5 to 10 and the tube 20°32.33, and the flammable gas and the electrical system will be protected gas. It is blocked by air, so the flammable gas cannot be ignited.

Further, if the pressure inside the boat 34 drops below a predetermined value for some reason, the sensor 36 detects this as described above and immediately cuts off the power supply to the motor units 5 to 10. As a result, even if flammable gas enters the container B of the motor units 5 to 10 or the tubes 20, 32, 33, the gas will not catch fire.

In the above description, a duct is provided inside the rotating section 16, but the present invention is not limited to this, and the inside of the rotating section 16 may be a sealed chamber.

Effects of the Invention As described above, the electric robot according to the present invention has an airtight chamber in the rotating part of the base and connects the cables from the terminal box to each motor via the airtight chamber. The outer circumferential dimension when a plurality of cables are assembled together can be smaller than when each cable has an internal pressure explosion-proof structure, and even when the number of cables is increased, the rotating part does not become large, which is advantageous in terms of design. Further, when the movable part on the base is rotated, twisting force does not act on the cable in the airtight chamber so much that the durability of the cable can be improved and its life can be extended.

[Brief explanation of the drawing]

1 and 2 are a side view and a rear view of an embodiment of the electric robot according to the present invention, and FIG. 3 is a vertical sectional view of the base of the present invention, and FIG. 4.5 is a longitudinal sectional view of the base. 6 is a longitudinal cross-sectional view and a cross-sectional view of the terminal box, and FIG. 6 is a cross-sectional view for explaining a tube hermetically connected to a duct and a cable inside the tube. 1...Base, 2... Rotating base, 13... Communication pipe, 14.15.17... Duct, 16... Rotating part,
20°23.25, 32.33...Tube, 21.
...Cable, 22.30...Moving cable, 24.
31...Signal cable.

Claims (1)

[Claims] A plurality of movable parts are provided on the upper part of the base, a plurality of motors for driving the movable parts are provided in the movable part, a terminal box is provided in the base for supplying power to the plurality of motors via cables, and the base An airtight chamber is provided in the rotating part of the base, one end of which communicates with the terminal box and a protective gas at a predetermined pressure is supplied, and the cable is connected to the motor from the other end of the airtight chamber through the airtight chamber. An electric robot characterized by: