KR0131993Y1 - Horizontal multi-joint robet - Google Patents

Abstract

The 3rd and 4th axis structure formed by the ball screw and the ball spline provided at the free end of the 2nd arm are integrated into one axis, and the weight is reduced and the compactness is achieved to reduce the rotational moment of inertia of the 2nd arm, In addition, the objective is to provide a horizontal articulated robot that can achieve other workability improvements in assembly.

Accordingly, the first arm pivotally fixed to the base and the second arm hinged to the first arm are rotated at a predetermined angle according to the operation of the uniaxial and biaxial motors as well as of the second arm. A horizontal articulated robot comprising a ball screw and a ball spline selectively lifted and rotated by a three-axis and four-axis drive unit provided at a free end, wherein the free end of the second arm is provided in a horizontal articulated robot. The third shaft is installed to be guided up and down, and the ball screw and the ball spline are separated, and the central axis is provided in the hollow space in the longitudinal direction so as not to be separated from each other. And, the guide fixedly installed on the upper end of the third shaft is guided as well as the guide fixedly installed on the second arm, the ball screw of the third It is fixedly installed on the toothed ball nut, and is provided with a three-axis drive unit consisting of a servo motor connected to a timing belt and a pulley for transmitting rotational force, and a spline nut coupled to the spline and spline of the third axis. It is characterized by consisting of a four-axis drive unit consisting of a servo motor connected to the pulley and the timing belt.

Description

Horizontal articulated robot

1 is a view showing the configuration of a horizontal articulated robot according to the present invention, (a) shows a raised state, (b) shows a lowered state.

2 is a perspective view of a horizontal articulated robot of the prior art.

3 is a side cross-sectional view for explaining the configuration of a horizontal articulated robot of the prior art.

The present invention relates to a horizontal articulated robot, and more particularly, to horizontally integrate two shafts with flanges installed in a holder to reduce weight, reduce rotational moment of inertia of these shafts, and improve assembly workability. It relates to a multi-joint robot.

In general, a horizontal articulated robot includes a plurality of arms and a plurality of rotational and elevating axes that receive power from a drive source.

This horizontal articulated robot is used as a means of transferring parts or products in an automated industrial site.

2 and 3 are diagrams for explaining the structure of a conventional horizontal articulated robot, which is generally used, and includes a horizontal moving part 1, a three-axis driving part 2, a lifting part 3, It comprises a four-axis drive unit (4).

The horizontal moving part 1 is pivotally fixed to the base B and has a first arm 5 which rotates on a horizontal line by the operation of the single-axis motor M, and the tip of the first arm. And a second arm 7 which rotates on the horizontal line by the biaxial motor M2.

The three-axis drive unit 3 is provided with a servo motor 10 inside the housing 8 provided at the free end of the second arm 7, and a pulley 11 is provided on the drive shaft of the servo motor. The ball screw 12 is to transmit the rotational force.

For this driving, the ball screw 12 is provided with a pulley 13 and the timing belt 14 is connected between the pulley 11 and the above.

The ball screw 12, the bearing 16 is installed in the fixing hole 15 formed in the second arm (7) to enable a smooth rotation, the bearing 16 is a bearing housing (17) ) Is inserted into the fixing hole 15 in a state of being inserted into the fixing hole 15 and fixed to the fixing means 18 such as a bolt.

The elevating portion 3 is configured such that the ball nut 20 holding the stopper 19 is nut-coupled to the ball screw 12 to selectively elevate the ball screw 12 according to the rotational direction of the ball screw 12.

The ball spline 21 which elevates together is rotatably provided in the said ball nut 20, and the lower end part of the ball spline 21 is rotatably provided and raises and rotates to the 2nd arm 7. As shown in FIG.

In addition, the ball spline 21 is installed in a state penetrating through the center of the pulley 22 rotatably installed on the second arm (7) for installing a holder (23) for holding parts and the like at the lower end ( 24).

The four-axis drive unit 4 has a servo motor 25 for transmitting the rotational force to the pulley 22 to substantially rotate the ball spline 21, the pulley on the drive shaft of the servo motor 25 (26) is provided and the timing belt 27 is connected between the pulley 22 and the above.

In the horizontal articulated robot of the prior art thus formed, when the single-axis motor M1 provided on the upper end of the base B is driven, the first arm 5 is rotated in the horizontal direction. Driving the M2 causes the second arm 7 to rotate in the horizontal direction.

In this state, when the servomotor 10 of the three-axis drive unit 2 is operated, the pulley 11 installed on the motor shaft rotates, and thus the rotational force is transmitted to the pulley 13 along the timing belt 14. The screw 12 is rotated.

When the ball screw 12 is rotated, the ball nut 20 which is nut-coupled to the ball screw is raised or lowered according to the rotation direction of the screw.

Then, the ball spline 21 which is rotatably installed at the upper end of the ball nut 20 is in combination with the ball nut 20 to move up and down.

Therefore, when the holder 23 adsorbs the component while the ball spline 21 is lowered, the ball spline may be raised again and transferred to the next step.

When the position of the holder 23 is out of the position where the component can be sucked when such a series of operations are performed, the servomotor 25 is driven to transmit the rotational force to the pulley 22 through the timing belt 27. Pass it.

Then, since the ball spline 21 is installed in this pulley 22, the ball spline 21 rotates when this pulley 22 rotates.

By this action, the position of the holder 23 can be adjusted.

However, the horizontal articulated robot of such a configuration uses a ball screw 12 for elevating operation and a ball spline 21 for elevating with the ball screw while correcting its posture by another driving source. It is the largest cause of increase.

Therefore, the rotational moment of inertia of the second arm is increased, resulting in a decrease in high speed performance, which in turn lowers workability.

In addition, as the two axes are used, the assembly work is complicated.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to provide a robot that is structurally simple and can improve the workability by minimizing the moment of inertia when the arm rotates. .

The technical matters provided to realize the object of the present invention as described above is to enable the conventional two-axis operation to a single axis.

That is, in a horizontal articulated robot having a means for rotating a plurality of arms installed in a base in a horizontal direction and configured to transfer parts through lifting and rotating movement of the shaft,

A second arm rotatably mounted to the first arm;

A third shaft integral with the ball screw and the ball spline and installed on the second arm;

A ball nut coupled to the ball screw and rotatably supported by the second arm to receive a rotational power from a servo motor to move the third shaft up and down;

A spline nut that is splined to the ball spline of the third shaft;

Provided is a horizontal articulated robot including yet another servomotor for rotating the third axis by transmitting rotational power to the spline nut.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in more detail.

1 is a view for explaining a horizontal articulated robot according to the present invention, (a) shows a raised state, (b) shows a lowered state.

Detailed description of parts described in FIGS. 2 and 3 in the drawings will be omitted.

On the free end of the second arm 7 rotatably coupled to the free end of the first arm 5, a single, unlike two axes (ball screw, ball spline) in FIGS. 2 and 3 are used. The third shaft 30 is used as the shaft.

It is the biggest feature of the present invention to perform the work that can be done conventionally with such a single axis.

Technical matters of the present invention for realizing this feature, the upper part of the third shaft 30 as the ball screw 31, the lower part as the spline 32, the shaft 33 penetrating the interior of these parts I integrate it.

The lower end of the third shaft 30 of this configuration is provided with a flange 24 in which the holder 34 is installed in the same manner as in the prior art, but the third shaft of the present invention rotates in the case of the conventional shaft. The third shaft is configured to be rotated by the servomotor 25 when the holder is held by the product by such lifting operation without raising or lowering.

That is, a ball nut 37 is coupled to the ball screw 31 of the third shaft 30, and the pulley 38 is positioned at the lower portion of the ball nut 37 and fixed to rotate together. The pulley 38 is configured to be capable of transmitting rotational force with the pulley 11 provided to the drive shaft of the servomotor 10 via the timing belt 39.

For this configuration, when the servomotor 10 starts to drive, the ball screw 31 does not rotate but only the ball nut 37 rotates, which is installed so that the bolt 37 does not move up and down. Since the ball screw 31, which is nut-coupled to the ball nut 37, is raised or lowered according to the rotational direction of the ball nut 37.

At this time, of course, the ball spline 32 integrally formed with the ball screw 31 also goes up or down without rotating.

As such, when the third shaft 30 moves up and down, the guide 36 is erected and installed on the second arm 7 so that the smooth lifting operation can be performed without swinging. (35) is attached to the upper end of the ball screw (31).

The support 35 may be installed to the sensor (S) in the upper portion of the guide 36 to detect the position of the top dead center may stop the drive of the servomotor 10.

The servo motor 10 mentioned above is installed as a power source for elevating the third shaft 30, and unlike this, the four-axis driving unit 4 is used only when the thirty shaft 30 is rotated. Another servo motor 25 is installed in the valve so that the servo motor 25 can be used only when the position of the flange 24 is corrected.

That is, when the third shaft (ball screw and ball spline) 30 moves up and down by the operation of the servo motor 10, the flange 24 only moves up or down and the flange 24 rotates only when the servo motor 25 is operated. To do it.

The servomotor 25 is a means for rotating the above-described ball spline 32, and is splined to the ball spline 32 and splined with a bracket C so as to be rotatable inside the second arm 7. The nut 40 is provided, and the pulley 41 is provided on the outer circumference of the spline nut 40 so as to receive the rotational power of the servomotor 25.

Between the above-mentioned pulley 41 and the servomotor 25, a large primary deceleration pulley 43 is provided as a deceleration means, and a small pulley on the same shaft 45 as the primary deceleration pulley 43 is provided. 44 is provided so that the pulley 41 can be used as a secondary deceleration pulley.

These pulleys are each capable of power transmission to the timing belts 42 and 46, and a tensioner 47 is provided to adjust the tension of the long timing belt 42. As shown in FIG.

The robot of the present invention, which is constituted as described above, has a timing belt (1) when the servo motor 10 is driven to lower the third axis while the third axis 30 is raised, as shown in FIG. 39) rotational power is transmitted to the ball nut 37 to rotate the ball nut.

By this action, the ball screw 31 to which the ball nut 37 is coupled is lowered. Since the ball spline 32 is installed in one axis at the lower end of the ball screw 31, To start. FIG. 1B shows a state in which the third shaft 30 is lowered.

At this time, the flange 24 provided on the ball spline 32 is also lowered, but since the servo motor 25 of the four-axis drive unit 4 is not driven, the flange does not rotate.

A holder 34 for holding a component is installed in the flange 24. When the position of the holder 34 is not a proper position for holding the component, the servo motor of the four-axis drive unit 4 25).

Then, the rotational power of the servomotor 25 is transmitted to the pulley 41 through the timing belts 46 and 42. Since the pulley 41 is fixed to the outer circumference of the spline nut 40, the spline nut is held together. Rotated.

Therefore, the spline nut 32 and the spline 32 of the third shaft 30, which is splined to the spline is rotated, the flange 24 to which the holder 34 is installed is rotated by this action.

When the flange 24 rotates by this action, the position of the holder 34 installed in the flange can be corrected, and the drive of the servomotor 25 can be determined by setting the position suitable for holding the component.

Then, the third shaft 30 is lowered to hold the component, and the servomotor 10 is driven to the raised position to proceed to the next step.

As described above, the horizontal articulated robot according to the present invention uses a plurality of axes in the prior art, but since a single axis is used, it is possible to reduce the rotational moment of inertia of the first arm or the second arm.

This makes it possible to speed up the horizontal rotational motion of the arm, thereby improving workability, and the single-axis structure makes the manufacturing process easier than in the multi-axis structure and solves all the problems of the prior art.

Claims (3)

A horizontal articulated robot having means for rotating a plurality of arms installed in a base in a horizontal direction and configured to transfer parts through lifting and rotating movement of an axis, so as to be pivotable on the first arm (5). A second arm 7 installed; A third shaft 30 in which the ball screw 31 and the ball spline 32 are integrated and installed on the second arm; A ball nut 37 coupled to the ball screw 31 and rotatably supported by the second arm 7 so as to receive a rotational power from the servo motor 10 and lift the third shaft; A spline nut (40) splined to the third ball spline (32); A horizontal articulated robot, comprising another servomotor (25) for rotating the third axis by transmitting rotational power to the spline nut (40). 2. The horizontal die of claim 1, wherein a pulley having a different diameter is installed between the servo motor 25 and the spline nut 40, and these pulleys are connected by a timing belt so that a deceleration action can be performed during power transmission. Articulated robot. The horizontal articulated robot according to claim 1, wherein a pulley (41) is installed on the outer circumference of the spline nut (40) to directly transmit the rotational force.