KR20020086394A - Spring Balancing Structure of Arm of Industrial Articulated Robot - Google Patents

Abstract

PURPOSE: A spring balancing structure used for an arm of an industrial robot is provided to save a cost required for a heat-treatment process by screw-coupling inner and outer flanges to inner and outer tubes. CONSTITUTION: A spring balancing structure includes an inner tube(2), an outer tube(9), a coil spring(3) positioned between the inner tube(2) and the outer tube(9), an outer flange installed at an upper end of the outer tube(9), and a spring supporter installed at a lower end of the outer tube(9). An inner flange is coupled to the upper end of the inner tube(2). A screw section is formed at an inner portion of the inner flange and the upper end of the inner tube(2) so that the inner flange is screw-coupled to the inner tube(2). A tip of the inner tube(2) is outwardly bent. A nipple is inserted into a lower end of the inner tube(2). The coil spring is wound around the inner tube(2).

Description

Spring balancing structure of the arm of industrial articulated robot

The present invention relates to a spring balancing structure of the arm of an industrial articulated robot, in general, the industrial robot used for the production of the product, the operation must be made exactly as desired, in particular, the accuracy even by the weight or vibration of the object on which the robot works It should be designed so that it is not affected by

The industrial robot is intended to perform the operation by performing a jointed articulated movement of several joints in order to achieve the correct operation as desired, so that the desired operation is executed correctly at the very end as the articulated movement is performed. In order to achieve this, multiple motors are used for each joint axis, rather than one power source.

That is, the motion of the joint axes connected to each other is made of a structure controlled by each motor.

Therefore, the accuracy of the operation of the industrial robot, the working range and the limits of the weight that the robot can handle are greatly influenced by the structure of the joint, that is, the connection structure of each axis.

For example, the arm structure of a conventional articulated robot has a casing of a low arm reducer inserted into a housing on one side of the pivot base, and a motor bracket is assembled to the casing, and is fixed to the pivot base by a bolt. The input shaft of the reducer is keyed to the motor shaft, and the arm motor for driving the low arm is fastened by a motor bracket, and the low arm is fastened by a bolt to the output shaft of the low arm reducer.

On the other hand, the casing of the upper arm reducer is inserted and fixed to the housing opposite to the turning base, the motor bracket is assembled to the casing, and is fixed to the turning base with a bolt, and the input of the reducer is attached to the motor shaft inside the upper arm. Gear is coupled, the upper arm motor is fastened by the motor bracket, the ball bearing is coupled to the output shaft of the lower arm reducer is coupled to the adapter equipped with a niros ring to prevent leakage of the ball bearing, the ball bearing The outer ring of is assembled to the lower arm and the connecting link is assembled to the adapter as a bowl.

That is, the joint of the robot arm having the structure as described above, the rotation of the lower arm motor is transmitted through the input shaft of the reducer, and as the casing of the reducer is fixed, the reduced rotational force is transmitted to the lower arm fixed to the reducer output shaft. The rotational force of the upper arm motor is decelerated by the upper arm reducer so that the upper arm motor can be transmitted to the upper arm through the adapter and the connecting link. The arm is the main factor affecting the degree of the workpiece, and the spring balance, which is the main component of the arm, is to assist the force when the arm of the robot returns after the movement, and the energy consumption of the electric motor It can be reduced by using elastic energy. The configuration of the spring balancing structure of the arm of the robot is to install a coil spring between the outer tube and the inner tube, and accumulate energy as elastic energy with respect to the reciprocating motion of the arm, and then discharge the joint and arm of the robot. Make sure the exercise is smooth.

Since this technique is well known in the art to which the present invention pertains, a detailed description thereof will be omitted. When roughly describing the processing process with respect to the spring balancing structure, first, the inner and outer flange and the inner and outer tube parts are welded to each other, and then the welding part is heat-annealed and precision as a finishing process. After turning, the specific part is ground after turning. Particularly, the hexagon nut part is heat treated with flame. In this case, the hardness is about HRC 15 ± 2. It is plated on the entire outer diameter of the tube, and the plating thickness is about 30 ± 3μ. The present invention in the spring balancing structure of the arm of the conventional articulated articulated robot, the technical difficulty due to the welding between the inner and outer flange and the tube, and accordingly the excessive expense due to the process such as annealing heat treatment as a post-process To improve such factors.

Accordingly, the present invention relates to a spring balancing structure of an arm of an industrial articulated robot, and in the spring balancing structure of an arm of a conventional articulated robot, a technical difficulty caused by welding between the inner and outer flanges and a tube. And according to the following to improve the factors such as excessive expense in the process such as annealing heat treatment as a post-process.

1 is a view showing an industrial articulated robot of the present invention

Figure 2 is a cross-sectional view of the spring balance structure of the arm of the industrial articulated robot of the present invention

3 is a partial detail view of the upper portion of FIG. 2;

4 is a partial detail view of the lower part of FIG.

Figure 5 is a cross-sectional view showing another embodiment of the present invention

<Explanation of symbols for main parts of drawing>

1 nut 2 inner tube

3: coil spring 4: thread part

5: external flange 6: nipple

8: inner flange 9: outer tube

10: spring support

The present invention relates to a spring balancing structure of an arm of an industrial articulated robot, and to the gist of the configuration, in the spring balancing structure of an arm of a general industrial articulated robot, the spring balancing structure includes an inner tube and an outer tube. And a coil spring located between the inner tube and the outer tube, and an outer flange installed at the upper end of the outer tube and a spring support provided at the lower end of the outer tube, wherein an inner flange of the spring balancing structure is provided at the upper end of the inner tube. The inner diameter portion of the inner flange and the outer diameter portion of the upper end of the inner tube are coupled to each other and are screwed tightly to each other, and the ends of the inner tube are bent outward to coke the upper surface of the coupling portion. Insert the nipple into the inner diameter of the inner tube at the lower end of the inner tube, The inner diameter of the lower end of the sub-tube and the nipple are each screwed together to form a screw tightly, but also the end of the inner tube is bent inward to coke the lower end of the coupling portion, the nut is fastened to the nipple It is fixed in close contact with the lower end of the inner tube, the coil spring is wound around the outer circumferential surface of the inner tube, and relates to a spring balancing structure of the arm of the industrial articulated robot, characterized in that it is placed between the inner tube and the outer tube.

In addition, the present invention is the outer diameter surface of the outer flange and the inner diameter portion of the upper end of the outer tube is formed with a screw thread is tightly coupled to each other, the upper end of the outer tube is bent inward to coke the upper surface of the coupling portion It is characterized by.

In particular, the winding direction of the coil spring is in the spring balancing structure of the arm of the industrial articulated robot, characterized in that the opposite direction to the screw direction of the spiral portion formed in the outer diameter, inner diameter, inner flange, outer flange and nipple of the inner tube. Invention. Such major components are described in detail in the accompanying drawings.

The present invention will be described in detail as follows. The present invention relates to a spring balancing structure of the arm of an articulated robot. The spring balancing structure is a major component that affects the degree of the product and enables the robot to perform the movement efficiently. As a main part thereof, there is a coil spring, and the present invention provides a more stable and inexpensive manufacturing method for placing the coil spring between an inner tube and an outer tube, and particularly, the inner and outer cylinders. The purpose of the above-described purpose is sufficiently achieved by screwing in joining the inner and outer flanges. In addition, as a result of adopting the screw coupling method instead of the welding process, there is an advantage that the manufacturing cost is reduced compared to the prior art by omitting the process of annealing heat treatment for the stress removal according to the conventional welding. The coil spring is placed between the inner flange and the lower spring support. The spring support has a hole in the center portion thereof so that the end of the inner tube can enter and exit downward through the hole. The outer flange fixes the inner flange on which the spring coil is mounted to the inside of the outer tube, and a connection ring is formed at the top of which the rod is bound. Accordingly, when the inner flange is lowered due to the external force applied to the end of the lower nipple, the coil spring is compressed, and when the inner flange is lifted, the coil spring is expanded.

In addition, the outer diameter surface of the outer flange and the inner diameter portion of the upper end of the outer tube is formed with a screw thread is tightly coupled to each other, the upper end of the outer tube is bent inward to coke the upper surface of the coupling portion, that is, Finish with curling.

In addition, a hexagon nut is fastened to the nipple by a hexagon nut is fastened to the lower end of the inner tube, the coil spring is wound around the outer circumferential surface of the inner tube, it is placed between the inner tube and the outer tube. Particularly, the hexagon nut part is heat treated with flame. In this case, the hardness is about HRC 15 ± 2. Likewise, the lower end of the inner tube is bent inwardly to caulk the bottom surface of the coupling portion.

The winding direction of the coil spring is made in the opposite direction to the screw direction of the spiral portion formed in the outer diameter portion, inner diameter portion, inner flange, outer flange and nipple of the inner tube.

This is to suppress the coil spring from loosening the screw portion due to the torque generated during operation.

In another embodiment, the round bar is used in place of the inner tube to be coupled to the inner flange, and when coupled, the round bar is fastened in a cooled state, thereby making the fastening more tight.

After that, precision turning is performed as a finishing process, and after turning, a specific part is ground. Particularly, the hexagon nut part is heat treated with flame. In this case, the hardness is about HRC 15 ± 2. It is plated on the entire outer diameter of the tube, and the plating thickness is about 30 ± 3μ.

As described above, the present invention, unlike the spring balancing structure of the arm of the conventional articulated robot, processes the joints of the inner and outer flanges and the inner and outer tubes with screws to remove welding defects, and is a post-treatment process according to welding. By eliminating the annealing heat treatment process, the manufacturing cost is reduced, and the joint portion between the inner and outer flanges and the inner and outer tubes is a useful invention having excellent quality such as mechanical strength and good aesthetics.

Claims (3)

In the spring balancing structure of the arm of an industrial articulated robot, the spring balancing structure includes an inner tube, an outer tube, a coil spring located between the inner tube and the outer tube, an outer flange installed at an upper end of the outer tube, It is composed of a spring support installed on the lower end of the outer tube, the inner flange of the spring balancing structure is coupled to the upper end of the inner tube, the inner diameter of the inner flange and the outer diameter of the upper end of the inner tube are each formed with a threaded portion Screwed tightly to each other, the ends of the inner tube are bent outwardly to caulk the top surface of the coupling portion; The nipple is inserted into the inner diameter of the inner tube at the lower end of the inner tube, and the inner diameter of the lower end of the inner tube and the nipple are each screwed together to form a threaded portion, but the end of the inner tube is inward It is bent to caulk the bottom surface of the coupling portion, the nut is fastened to the nipple is fixed tightly to the lower end of the inner tube; The coil spring is wound around the outer circumferential surface of the inner tube, the spring balancing structure of the arm of the industrial articulated robot, characterized in that it is placed between the inner tube and the outer tube. According to claim 1, wherein the outer diameter surface of the outer flange and the inner diameter of the upper end of the outer tube is formed with a screw thread tightly coupled to each other, the upper end of the outer tube is bent inward to caulk the upper end of the coupling portion Spring balancing structure of the arm of an industrial articulated robot. According to claim 1, wherein the winding direction of the coil spring of the arm of the industrial articulated robot, characterized in that the direction opposite to the screw direction of the spiral portion formed on the outer diameter, inner diameter, inner flange, outer flange and nipple of the inner tube. Spring balancing structure.