JPH06126662A - Industrial robot - Google Patents

Abstract

PURPOSE:To secure such a robot as capable of short-circuiting a tact time for conveyance and assemblage by installing two symmetrical end effectors being connected to a belt and driven by this belt in the reverse direction with each other along an arm. CONSTITUTION:When a work 14 held by an end effector 7 at the right is fed to a work 17 so far fed, as shown in an arrow D, from the right direction in a state of being mounted on a belt 16a, by a belt conveyor 16, another end effector 6 at tone left driven rearward by a timing-belt 10 and a slider 3B attracts a platelike work 18 mounted on top of a pallet 13B at the left. Conversely, when the work mounted on top of a pallet 13A at the right is held by the end effector 7 at the right, the work 18 attracted by the end effector 6 at the left driven frontward by the timing belt 10 and a slider 3A likewise is fed to the work 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial robot, and more particularly to an industrial robot having a plurality of end effectors.

[0002]

2. Description of the Related Art As is well known, industrial robots have a rectangular coordinate robot, a cylindrical coordinate robot, a rectangular coordinate robot, from the viewpoint of operation mechanism, as defined in Japanese Industrial Standards (JISB0134).
There are polar coordinate robots and joint robots, but in any type of industrial robot, the number of axes that constitute the degree of freedom of movement is the same as the number of operating axes on the mechanism, and for one degree of freedom Is composed of one motion axis.

FIG. 3 is a perspective view showing an example of a rectangular coordinate robot having three axes of freedom. In FIG.
Mounting plates 1a are provided on the lower surfaces of the left and right ends of the X-axis arm 1 that serves as a support portion for the first shaft, and each mounting plate 1a is
Each of the industrial robots is fixed to a support frame 20 shown by a chain line, which is erected on the floor where the industrial robot is installed.

Inside the X-axis arm 1, a ball screw and a guide rail (not shown) are provided in the left-right direction in FIG. 3, and a nut (not shown) fitted to the ball screw is provided on one side of a slider (not shown). Is attached. At the right end of the X-axis arm 1, an AC servo motor (hereinafter referred to as a motor) for driving a single shaft, whose output shaft is connected to the right end of a ball screw, is housed.

The Y-axis arm 2 whose rear end is placed opposite to the upper surface of the X-axis arm 1 and serves as a support portion for the second shaft has the lower surface of the rear end fixed to the other side of the above-mentioned slider, and as a result, the Y-axis. The arm 2 is driven by a motor (not shown) housed at the right end of the X-axis arm 1 described above, and a ball screw connected to this motor rotates, so that the X-axis is indicated by arrows G1 and G2 in FIG. Driven linearly in the direction.

Like the X-axis arm 1, inside the Y-axis arm 2, a ball screw (not shown) and a guide rail are provided in the front-rear direction in FIG. 3, among which a nut (not shown) fitted to the ball screw is provided. Is attached to the left side of a slider (not shown). At the rear end of the Y-axis arm 2, an unillustrated two-axis drive motor, whose output shaft is connected to the rear end of the ball screw, is housed similarly to the X-axis arm 1.

The Z-axis unit 4, which has the left-hand side opposite to the right-hand side of the Y-axis arm 2 and serves as a support portion for the third shaft, is fixed at the center of the left-hand side to the other side of the above-mentioned slider.
The shaft unit 4 is driven by a motor (not shown) housed at the rear end of the Y-axis arm 2 described above, and a ball screw connected to this motor rotates, so that the arrow H in FIG.
As indicated by 1 and H2, linear drive is performed in the Y-axis direction.

Inside the Z-axis unit 4, an upper portion of a tubular arm 4a is vertically accommodated vertically via a bearing (not shown), and a rack (not shown) is vertically provided from an intermediate portion to an upper end of the arm 4a. It is fixed to. A pinion (not shown) attached to the output shaft of a drive motor (not shown) housed inside the Z-axis unit 4 meshes with this rack. As a result, the arm 4a drives the motor inside the Z-axis unit 4 so that the pinion and the rack described above move in the Z direction as indicated by the arrow J in FIG.
It is driven in the axial direction (that is, the vertical direction). Arm 4
At the lower end of a, an end effector 5 shown by a chain line is
A drive source (not shown) is built in and attached.

By the way, in the industrial robot configured as described above, when one industrial robot is made to perform two different works (for example, the transfer work of different works), conventionally, the following two methods are used. One of these methods is adopted.

One of them is Z, as shown in FIG.
An operating mechanism 21 that further swings in the direction of arrow K is provided at the lower end of the arm 4a of the shaft unit 4, and an end effector (Note: FIG. 4 (a) shows the adsorption mechanism on the operating shaft on one side of this operating mechanism 21). ) 6 is attached, and the end effector 7 different from the end effector 6 is attached to the operating shaft on the other side (Note: FIG. 4 (a)).
A gripping mechanism is shown), and the end effector 6 and the end effector 7 are rocked and switched as shown by an arrow L, and the end effector 6 performs the palletizing work by suction, and the end effector 7 performs work gripping. Perform palletizing.

The other one is Z as shown in FIG.
At the lower end of the arm 4a of the shaft unit 4, a tool changer
24 is attached, and the end effector 6 attached to the tool changer 24 and the end effector 7 shown in FIG. 4C are exchanged alternately for palletizing.

[0012]

However, each of the industrial robots thus configured has the following problems.

First, in the former industrial robot having the tip structure of FIG. 4A, the tip of the arm 4a becomes heavy because of the operation mechanism 21 and the end effectors 6 and 7 attached to the tip of the arm 4a. Therefore, not only the capacity of the driving motor housed inside the Z-axis unit 4 must be increased, but also the time required for switching the end effectors 6 and 7 increases the working time.

In the latter industrial robot having the tip mechanism shown in FIGS. 4B and 4C, each time the end effectors 6 and 7 are replaced, the Y-axis arms 2 and Z shown in FIG.
Since the axis unit 4 and the arm 4a have to be operated, this not only prolongs the working time, but also requires equipment for fixing these tools in place. Then, the objective of this invention is to obtain the industrial robot provided with the some end effector which can shorten tact time.

[0015]

SUMMARY OF THE INVENTION An industrial robot according to the present invention comprises an arm driven by a first drive unit, a belt attached to the arm and swung by a second drive unit, and A plurality of end effectors connected to each other and driven in opposite directions along the arm by the belt are provided.

[0016]

A plurality of works having different positions are alternately transported to the transport point by the plurality of end effectors driven in opposite directions.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the industrial robot of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an industrial robot of the present invention and a working example thereof, and FIG. 2 is a plan view showing a main part of FIG. 1, corresponding to FIG.

1 and 2, pulleys 11A and 11B are attached to both ends of the Y-axis arm 2 as shown in FIG. 2, of which the shaft of the pulley 11A is the output shaft of a motor (not shown). It is connected. These pulleys 11
A timing belt 10 is wound around A and 11B.

As shown in FIG. 2, linear guide rails 8A and 8B are provided symmetrically in parallel with the timing belt 10 over the entire length of the Y-axis arm 2 at the right and left intermediate portions of the Y-axis arm 2. Has been.

An arrow B in FIG. 1 is provided on both sides of the Y-axis arm 2.
3, B4, and a slider 3A that is movable in the directions of arrows F1 and F2 in FIG. 2 are provided by being fitted to the linear guide rail 8A. The slider 3A includes a first Z-axis unit 4
The left side of A is fixed.

Similarly, on the other side of the Y-axis arm 2, a slider 3B which is movable in the directions of arrows B1 and B2 in FIG. 1 and arrows F3 and F4 in FIG. It is provided by fitting. The right side surface of the second Z-axis unit 4B is fixed to the slider 3B.

The front right side of the timing belt 10 wound around the pulleys 11A and 11B is connected to the slider 3A, and the rear left side of the timing belt 10 is the slider 3A.
Bound to B.

At the lower end of the arm 4a protruding downward from the first Z-axis unit 4A on the right front side, an end effector 7 is attached with a drive source (not shown) incorporated therein, and at the tip of this end effector 7, a work is attached. 14 is gripped.

Similarly, the end effector 6 shown in FIGS. 4 (a) and 4 (b) is attached to the tip of the arm 4b shown by the dotted line in FIG. 1 protruding downward from the second Z-axis unit 4B. ing.

In the industrial robot configured as described above, the timing belt 10 is driven according to the pulley 11A which is rotated by driving a motor (not shown) housed at the base end of the Y-axis arm 2, and accordingly, the timing belt 10 is driven. When the slider 3A on one side is driven in the direction of arrow B3 in FIG. 1, the slider 3A on the other side is driven in the direction B2, and when the slider 3A is driven in the direction of arrow B4 in FIG. The sliders 3B move in the directions of arrow B1 and in the opposite directions. Next, the operation will be described with reference to an example of a work assembling work which is a typical work of the Cartesian robot.

As shown in FIG. 1, an arrow D is drawn from the right direction while being placed on the carrier 16a by the belt conveyor 16.
When the work 14 gripped by the right end effector 7 is supplied to the work 17 sent as shown by, the left end effector 6 driven rearward by the timing belt 10 and the slider 3B moves to the left end. Pallet 13B
The flat plate-shaped work 18 placed on the upper surface of is adsorbed.

On the contrary, when the right end effector 7 grips the work placed on the upper surface of the right pallet 13A, it is adsorbed by the left end effector 6 which is also driven forward by the timing belt 10 and the slider 3A. The work 18 is supplied to the work 17.

During loading and unloading of these works 14 and 18, arrows A1 and A in FIG.
2 and a Y-axis arm 2 indicated by arrows E1 and E2 in FIG.
The moving distance in the X-axis direction is a value obtained by subtracting the distance between the left and right arms 4a and 4b from the distance between the works 14 and 18 placed on the left and right pallets 13A and 13B. , And Z in the biaxial directions shown by arrows B1, B2, B3, B4 in FIG. 1 and arrows F1, F2, F3, F4 in FIG.
Also in the operation of the shaft units 4A and 4B, when one side is positioned in front, the other side can be positioned on the pallet, so that the work 14 and 18 can be supplied to the work 17 in a short time.

In the above embodiment, the Z-axis units 4A, 4B were moved by the pulleys 11A, 11B and the timing belt 10, but they may be moved by a sprocket and a chain depending on the positioning accuracy. .

Further, in the above embodiment, the description has been made on the case of the three-axis orthogonal Cartesian coordinate robot. However, for example, the above-mentioned can be applied to the arm of the cylindrical coordinate type industrial robot and the joint type robot or the polar coordinate type industrial robot. A timing belt may be provided to attach the two end effectors.

[0031]

As described above, according to the present invention, the arm driven by the first driving unit, the belt attached to the arm and swung by the second driving unit, and the belt connected to the belt. By having a plurality of end effectors that are driven in opposite directions along the arm by, the plurality of workpieces having different positions are alternately transported to the transport point by the plurality of end effectors that are driven in opposite directions. Therefore, it is possible to obtain an industrial robot including a plurality of end effectors capable of shortening the takt time.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an industrial robot of the present invention.

FIG. 2 is a plan view of a main part showing an embodiment of the industrial robot of the present invention.

FIG. 3 is a plan view showing an example of a conventional industrial robot.

FIG. 4A is a perspective view showing a final stage operation axis of a conventional industrial robot. (B) is a perspective view showing a final stage operation axis different from (a) of the conventional industrial robot different from (a). (C) is a perspective view showing an example of an end effector attached to a conventional industrial robot.

[Explanation of symbols]

1 ... X-axis arm, 2 ... Y-axis arm, 3A, 3B ... Slider, 4A, 4B ... Z-axis unit, 5, 6, 7 ... End effector, 8A, 8B ... Linear guide rail, 10 ... Timing belt, 11A, 11B ... Pulley, 14, 17, 18 ... Work, 16 ... Belt conveyor.

Claims (1)

[Claims] 1. An arm driven by a first drive unit, a belt attached to the arm and swung by a second drive unit, and a belt connected to the belt and being opposite to each other along the arm. An industrial robot having a plurality of end effectors driven in a direction.