JP2554994Y2 - Robot tool axis position repeatability measurement device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position repeatability measuring device for a tool axis of a robot.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 9 to 11, a target 102 is fixed to a tip of a tool shaft 101 attached to a tip of a robot arm (not shown). 2. Description of the Related Art There is known a robot arm accuracy measuring device in which a displacement meter 104 is installed on a movement trajectory 103 of a target 102 (in a horizontal direction). The displacement meter 104 is detachably mounted on the same base 10 as the robot by a magnet 105.
6 fixed on.

Next, the operation will be described. First, the target 102 is lightly brought into contact with the tip of the displacement meter 104, the position is set to "0", and the initial positioning is performed. Next, the arm of the robot is repeatedly operated, and its repetition accuracy is measured.

[0004]

However, in the above-mentioned prior art, even if the arm is operated repeatedly, the same locus 103 is not always taken.
When the center of the get 102 is shifted as shown in FIG. 11, there is a problem that such a shift cannot be measured.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide an apparatus for measuring the repeatability of the position of a tool shaft attached to the tip of an arm of a robot. The gauges are arranged so that their axes are orthogonal to each other and on the movement locus of the tool axis.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An initial positioning member 4 having an initial positioning hole 3 is mounted on a base 2 on which a fixing magnet 1 is mounted. On the base 2, two displacement gauges 5, 6 are fixed. Then, the axes 9 and 10 of the contact portions 7 and 8 of the displacement meters 5 and 6 are orthogonal to each other, and the axis 1 of the hole 3 in the vertical direction.
Displacement gauges 5 and 6 are attached so that the intersection of 1 and the axes 9 and 10 intersects.

Further, a base 2 has an air cylinder type release driving mechanism 1 for moving the contact portions 7, 8 forward and backward.
2 (see FIGS. 3 to 5) is fixed. 13,14
Is a release (cable) for interlocking the contact portions 7, 8 with the release mechanism.

On the other hand, a target 16 is mounted on a tool shaft 15 of a robot arm (not shown) coaxially with the tool shaft 15, and a lower end of the target 16 is provided. Is formed with an initial positioning dog 17.

FIG. 6 is a schematic diagram showing the system of the present invention, and FIG. 7 is a flowchart showing a procedure for measuring accuracy.

[0010] Incidentally, an example of the accuracy measurement is shown by the following equation based on FIG. Center of circle with radius r is origin 0
From △ x and △ y to 0 ′ (u, u,
Find v). However, 0 'is the number 1 which does not go outside the circle 0

(Equation 1) A point where the circle 0 'intersects the x-axis and the y-axis is represented by A (x,
0) and B (0, y). When a circle with a radius r is drawn around the points A and B, one of the intersections is 0 'and the other is C. Assuming that the intersection of the straight line 0'C and the straight line AB is D, the coordinate of D is

(Equation 2) Is the midpoint of Where Equation 3

(Equation 3)

Next, the operation will be described. First, the initial positioning dog 17 is fitted into the initial positioning hole 3, and this position is set to "0". That is, the reference position is set. Next, the arm of the robot is repeatedly operated, the deviation from the reference position is measured, and the accuracy of the robot is calculated.

When the contact type displacement gauges 5 and 6 are used, the contact portions 7 and 8 are relayed while the tool shaft 15 is operating.
When the tool shaft 15 is stopped, the contact portions 7 and 8 are made to protrude, and the target 16 is retracted.
To measure the deviation from the reference position. In addition,
It goes without saying that the operation of the system and the in / out operations of the contact portions 7 and 8 are automatically linked.

[0013]

According to the present invention, there is provided an accuracy measuring device for position repeatability of a tool shaft attached to a tip of an arm of a robot, wherein two displacement gauges are arranged so that their respective axes are orthogonal to each other, and Since it is arranged on the movement locus of the tool axis, it is possible to provide an accuracy measuring device capable of accurately measuring the accuracy of the robot.

[Brief description of the drawings]

FIG. 1 is an external perspective view of an embodiment of the present invention.

FIG. 2 is an external perspective view in which a tool shaft is arranged in FIG.

FIG. 3 is a release mechanism for moving the displacement meter of FIG. 1;
FIG.

4 is a release mechanism for moving the displacement meter of FIG.
FIG.

FIG. 5 is a sectional view taken along the line AA of FIG. 4;

FIG. 6 is a schematic diagram showing the system of the present invention.

FIG. 7 is a flowchart showing the operation of the present invention.

FIG. 8 is a basic diagram for performing precision measurement based on the present invention.

FIG. 9 is a front view of a conventional device.

FIG. 10 is an explanatory plan view at the time of measurement according to FIG. 9;

FIG. 11 is a view showing a shift of a tool axis in FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixing magnet 2 Base 3 Initial positioning hole 4 Initial positioning member 5 Displacement meter 6 Displacement meter 7 Contact part 8 Contact part 9 Contact part axis 10 Contact part axis 11 Vertical axis 12 Air cylinder Type release drive mechanism 13 Release 14 Release 15 Tool shaft 16 Target 17 Dog for initial positioning

 ────────────────────────────────────────────────── (5) References JP-A-62-231310 (JP, A) JP-A-63-156686 (JP, A) JP-A-63-283888 (JP, A) JP-A-63-283888 55408 (JP, A)

Claims (7)

(57) [Scope of request for utility model registration] An accuracy measuring device for a position repeatability of a tool axis attached to a tip of an arm of a robot.
An apparatus for measuring the position repeatability of a tool axis of a robot, wherein two displacement gauges are arranged so that their respective axes are orthogonal to each other and on the movement locus of the tool axis. 2. The apparatus according to claim 1, wherein the displacement meter is a contact type displacement meter. 3. The apparatus according to claim 1, wherein said displacement meter is a non-contact type displacement meter. 4. The position of the tool axis of the robot according to claim 1, wherein the contact portion of the contact type displacement meter is moved according to the operating position of the arm of the robot. Repeatability measuring device. 5. An accuracy measuring device for position repeatability of a tool shaft attached to a tip of an arm of a robot.
The two displacement gauges are arranged so that their axes are orthogonal to each other and on the movement locus of the tool axis, an initial positioning member having an initial positioning hole is arranged, and the axis of the hole is arranged. And the two displacement gauges are arranged so that their intersections are orthogonal to each other, and the initial positioning is performed by fitting a dog of a target attached to the lower end of the tool shaft into the hole. For measuring the position repeatability of the tool axis of a robot. 6. A control device for automatically measuring upon receipt of a position arrival signal from a robot controller, a memory for storing data, and a computing device for processing data. 6. The apparatus for measuring the position repeatability of a tool axis of a robot according to claim 5. 7. The apparatus according to claim 6, wherein the two displacement meters are freely fixed at arbitrary positions in accordance with the operation range of the robot.