JPH0675654U - Circumferential grinding wheel wear compensation device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a device capable of constantly compensating the wear to make the finish state constant even if the grinding tool used for deburring and polishing the circumferential surface by the robot wears. The purpose is to [Arrangement] The posture of the grinding blade (4) is not changed constantly according to the normal direction of the cylindrical surface of the workpiece (1), and when the grinding blade (4) is worn, the workpiece (1) Cutting tool (4) toward the center of the cylindrical surface
The wear is corrected by moving the coordinates.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a circumferential grinding wheel wear correction device capable of correcting wear of a grinding tool used for deburring and polishing a circumferential surface by a robot.

[0002]

[Prior art]

 Currently, when performing deburring and polishing work by a robot, deburring and polishing work is performed by pressing the rotation center of the grinding wheel so that it is always in the normal direction of the work.

An example thereof is shown in FIG. As shown in the figure, when polishing the outer peripheral surface of a cylindrical work 01, an internal grinder 03 is attached to the robot wrist 02, and the rotation center of the grindstone 04 with a shaft at the tip of the internal grinder 03 is changed. While rotating the wrist 02 so that the workpiece 01 is always in the normal direction, the grindstone 04 with a shaft is brought into contact with the workpiece 01 for polishing.

Here, the operating range of the wrist 02 is generally about ± 100 °, and the operating range of the robot hand 02 is limited. Therefore, it is difficult to direct the rotation center of the grindstone 04 with a shaft over the entire surface of the work 01 and to direct it in the normal direction, and only half the circumference of the work 01 can be polished. Therefore, in practice, the cylindrical work 01 is divided into four, and the work is performed for each area.

In the above polishing process, when the grindstone 03 with a shaft is worn and the diameter is reduced, a correction (wear correction) is performed to move the coordinate of the taught tool center point in parallel according to the wear amount. ing. That is, when teaching the robot, as shown in FIG. 5, the cylindrical work 01 is actually divided into four, and the tip of the rotation center of the grindstone with shaft 04 is divided into tool centers for each area. Although teaching is performed as a point, when the grindstone 03 with a shaft is worn, the coordinates of the tool center point are translated in parallel for each area.

Specifically, as shown in FIG. 5, in the area A in the upper right of the figure, the coordinates of the tool center point are moved diagonally downward to the left, and in the area B in the lower right of the figure, the coordinates of the tool center point are shown. The coordinates are diagonally upward in the left direction, in the lower left area in the figure, the coordinates of the tool center point are diagonally upward in the right direction, and in the upper left area D in the figure, the coordinates of the tool center point are parallel in the diagonally downward right direction. It is moving.

[0007]

[Problems to be solved by the device]

 However, in the above-mentioned wear correction, the tool center points are only moved in parallel in each of the areas A to D, and it is not possible to move all the tool center points in the direction of the center of the circle accurately, resulting in high accuracy. Polishing is difficult.

For example, as shown in FIG. 5, if the tool center point T is moved in parallel to the center of the circle, the tool center points T ′ and T ″ will not move in the center of the circle. Therefore, the distance to the contact point is different at each tool center point T, T ', T ", and even if the tool center point T makes contact, the tool center points T', T" Then you will not be in contact.

Further, by increasing the number of divisions, it becomes easier to move the teaching point in the direction of the center of the circle. However, in general, a plurality of points are complemented between the tool center points. There is a limit to the increase in the number of divisions. The present invention has been made in view of the above-mentioned conventional art, and an object thereof is to provide an apparatus capable of constantly correcting the wear and keeping the finishing state constant even when the cutting tool is worn.

[0010]

[Means for Solving the Problems]

 The configuration of the present invention which achieves such an object is the posture of the grinding blade according to the normal direction of the cylindrical surface of the workpiece when deburring or polishing the cylindrical surface of the workpiece by the robot with the grinding blade. When the grinding blade is worn, the wear is corrected by moving the coordinates of the grinding blade toward the center of the cylindrical surface of the workpiece.

[0011]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. In this embodiment, as shown in FIG. 3, unlike the conventional technique in which the cutting tool rotation center is always in the normal direction of the workpiece 01, the direction of the rotation center of the cutting tool 2 of the grinder 3 is as shown in FIG. This is performed without changing the direction of the normal of the work 1 while keeping it constant. Therefore, it is not necessary to rotate the robot wrist 4 that holds the grinder 3.

First, as shown in FIG. 1, the number of divisions of the circular work 1 is predetermined. This is to determine the angle θ formed by the origin at each point of the cutting tool. That is, in this embodiment, it is an absolute condition to accurately obtain θ, so it is difficult to apply the teaching playback method in which θ cannot be accurately obtained to this embodiment. If θ is known, as shown in FIG. 1, when the radius r _{1 of the} work 1 and the radius r ₂ of the cutting tool 4 are set, the coordinates (x ₁ , y ₁ ) of the cutting tool 4 at the angle θ are It is shown by the following formula.

X ₁ = − (r ₁ + r ₂ ) sin θ (1) y ₁ = (r ₁ + r ₂ ) − (r ₁ + r ₂ ) cos θ (2) However, the coordinate origin is the cutting tool 4 at the work origin. The coordinates of the rotation center of. Therefore, as shown in FIG. 1, when the work start point of the cutting tool 4 is fixed at a fixed position, the radius r _{1 of the} work 1 and the degree of circular division can be input to determine the trajectory of the cutting tool 4 and teaching It becomes unnecessary. Here, when the cutting tool 4 wears, the radius r ₂ of the cutting tool 4 decreases. At that time, if the value is substituted into the equations (1) and (2), θ is constant, so that the normal direction of the work 1 Therefore, it becomes possible to make correction in the direction of the center.

That is, when the wear correction of the present embodiment is performed, as shown in FIG. 4, all the positions of the cutting tools are corrected so as to move toward the center of the work 1, so that the finished state of the work 1 is corrected. Is fixed, and satisfactory processing can be performed. However, in the case of implementing this method, it is necessary to use r ₂ , x ₁ , and y ₁ as variables and calculate all the correction coordinates after the wear measurement of the cutting tool. Therefore, in this embodiment, the manual data input (MDI) method is preferably used. In this method, the workpiece contact point (machining point) of the cutting tool is specified by three-dimensional coordinates based on the positional relationship between the robot and the workpiece, and is performed by manually writing in a predetermined program.

As described above, the teaching, which has been necessary until now, is unnecessary, and the wear of the cutting tool, for example, the grindstone or the flap wheel can be corrected toward the center of the circle. In addition, the coordinates can be changed by calculation even if the grinding wheel diameter is extremely different, and the correction by teaching is not necessary. In the above embodiment, the work is divided into a plurality of pieces, but it is divided for convenience, and the work 1 does not need to be divided. Even the teaching playback method can be applied by adding a measuring machine to the tool so that accurate measurement can be performed.

[0016]

[Effect of device]

 As described above in detail with reference to the embodiments, according to the present invention, when the circular work is deburred or polished by the grinding tool, the posture of the tool is kept constant and If the grinding tool wears, the wear is corrected toward the center of the work piece so that teaching is not required and the work piece is always in contact and stable. Work can be performed and the finished state of the work becomes constant.

[Brief description of drawings]

FIG. 1 is a principle view of the present invention.

FIG. 2 is an explanatory view showing a posture of a cutting tool with respect to a work.

FIG. 3 is an explanatory view showing a posture of a cutting tool with respect to a work in a conventional method.

FIG. 4 is an explanatory diagram showing the direction of wear correction in the present embodiment.

FIG. 5 is an explanatory diagram showing a direction of wear correction by a conventional method.

[Explanation of symbols]

 1,01 Workpiece 2,02 Robot wrist 3,03 Grinder 4,04 Grinding cutting tool

Claims (1)

[Scope of utility model registration request] 1. When deburring or polishing a cylindrical surface of a work by a robot with a grinding blade, the posture of the grinding blade is kept constant according to the normal direction of the cylindrical surface of the workpiece. In the case where the grinding blade is worn, circumferential grinding is performed by moving the coordinates of the grinding blade over the entire circumference of the cylindrical surface of the work toward the center thereof. Whetstone wear correction device.