JP2006064471A - Measurement method and measurement instrument for turning radius size of workpiece - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measurement method and a measurement instrument for measuring the turning radius size of a workpiece (a turning component) with high accuracy and with satisfactory repeatability. <P>SOLUTION: On the workpiece 1 which is a pressed article with a shaft hole bored in an ear part 1a formed on one end thereof, the turning radius size R of the shaft hole from its center to an end thereof is measured by the undermentioned measuring method and instrument. That is, a workpiece holding tool 2 mounted on a carrier robot is carried to a loading/measuring position, and a reference pin 8 provided on the holding tool 2 is fit by insertion in the shaft hole in the workpiece 1 and set at a loading position (Fig. (a)). Meanwhile, a clamp-type swing mechanism for turning the workpiece centering on the reference pin and a linear gage 7 conformed to the turning movement locus of an end of the workpiece are provided in a measurement position (Fig. (b)). The workpiece 1 put between clamp fingers 4a is turned around the reference pin at the measuring position to cause the end of the workpiece to push a probe of the linear gage in the course of this swing process. Here, the radius size R of the workpiece is measured with the maximum value of measurement output obtained from the linear gage (Fig. (c)). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a measuring method and a measurement method for measuring a rotating radius dimension of a workpiece manufactured by a press working method with high accuracy and high reproducibility, for example, for a rotating part (lever) used for an opening / closing mechanism of a circuit breaker. Relates to the device.

One of the parts constituting the circuit breaker switching mechanism is a rotating part having a shape as shown in FIG. 6 (one end of the part is pivotally connected to the drive shaft as a hinge, and the tip of the part is moved by the rotating operation. The open / close mechanism is tripped by hitting another part, which is hereinafter referred to as “workpiece”), and this part is usually mass-produced by a press working method. By the way, because the finished dimensions of pressed products vary due to variations in the thickness of the material (steel plate) that is put into the pressing process, especially the radius of rotation of the rotating parts, the workpiece is checked by sampling in the manufacturing process. The external dimensions (rotational radius dimensions) are measured and compared with the dimensions determined by the specifications, and if it is determined to be defective, the dimensions of the product are corrected by adjusting the press die.
Next, examples of the shape of the workpiece are shown in FIGS. In the figure, the workpiece 1 is made of a steel plate and has a bifurcated ear 1a bent at one end thereof, and a hinge shaft hole 1b is drilled, and the tip side of the workpiece 1 is bent in an L shape. Then, the distance from the center to the tip of the shaft hole 1a is set as the rotation radius dimension R. In the workpiece sampling inspection, the rotation radius dimension R is measured, and this measurement dimension is compared with the specification dimension (master dimension). The quality of manufactured parts is judged.

  In this case, as a method for measuring the rotational radius R of the workpiece, in the conventional method, the positioning is set through the shaft hole 1b of the workpiece 1 to be measured shown in FIG. An operator actually measures the distance from the reference pin to the tip of the workpiece using a dial gauge, and makes a pass / fail judgment based on the measured value. The dimensional accuracy required for this work is on the order of μm.

By the way, in the conventional measurement method by the above-mentioned manual work, it takes time and labor to set up the positioning set on the workpiece measurement jig, measure with the dial gauge, and record work, and the skill of the dial gauge measurement operation. Therefore, there is also a problem of reliability of measurement data such that the measurement value changes as the measurement operator changes. In addition, if the time taken for measurement of this sampling inspection greatly affects the workpiece manufacturing process and the yield rate, it is desirable to develop a measuring method and apparatus that can perform highly accurate measurement with high reproducibility in a short time. Yes.
The present invention has been made in view of the above points, and its object is to provide a measuring method capable of measuring the rotational radius R of a workpiece (rotating part) having the above-described shape in a short time with high accuracy and good reproducibility. And providing a measuring device.

In order to achieve the above object, according to the present invention, for a workpiece to be a press-processed product in which a shaft hole is drilled in a bifurcated ear formed at one end, a rotational radius dimension from the center of the shaft hole to the workpiece tip is obtained. Shall be measured by the following method.
That is, after inserting the shaft hole into the measurement reference pin and setting the workpiece at the measurement position, a linear gauge probe (measuring element) is placed on the rotational movement locus of the workpiece tip around the reference pin. In this state, while rotating the workpiece around the reference pin, the rotational radius dimension of the workpiece is measured with the maximum value of the measurement output obtained from the linear gauge in the swing stroke.
On the other hand, a measuring apparatus according to the present invention for carrying out the measuring method includes a work holding jig for inserting a reference pin from the left and right into a shaft hole of a work and holding the work in a predetermined direction, and the work holding jig. A transfer robot that moves between a workpiece loading position and a measurement position by mounting a tool, a positioning mechanism that locks and holds a workpiece holding jig at a predetermined position at the measurement position, and a reference pin that clamps the workpiece The workpiece is set on the workpiece holding jig at the loading position, and is composed of a swing mechanism that rotates around the reference pin and a linear gauge with a probe placed on the tip movement locus of the workpiece that rotates around the reference pin at the measurement position. The robot is transported to the measurement position, the workpiece is swung around the reference pin at this measurement position, and the tip of the workpiece is pushed against the linear gauge probe during the swing. And Te measuring the rotation radius of the workpiece (claim 2).

  Further, in the above measuring apparatus, as a means for enabling measurement with constant reproducibility under constant measurement conditions, the work holding jig is configured such that the work is pressed from a fixed direction while the work is set. A pusher for pressing the hole against the reference pin is provided. Further, as a positioning mechanism for holding the workpiece holding jig at a predetermined measurement position on the transfer robot, a positioning hole is provided in the workpiece holding jig and a positioning pin is provided on the transfer robot side, and the positioning pin is positioned at the measurement position of the transfer robot. So that the work holding jig is positioned and held at the measurement position.

  According to the above measuring method and apparatus, all of the steps of transferring to the measuring position and measuring the rotational radius dimension are performed automatically by simply setting the measuring work on the work holding jig at the loading position of the transfer robot. Compared with the manual measurement method using the dial gauge, the measurement time is shortened, the measurement positioning accuracy is improved, and stable reproducibility is always obtained even in repeated measurement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a measuring apparatus according to the present invention and a measuring method for measuring a rotational radius dimension of a workpiece using the measuring apparatus will be described below based on examples shown in FIGS.
First, FIG. 2 shows the overall structure of the measuring apparatus. In FIG. 2, 2 is a work holding jig for mounting the measurement work 1 shown in FIG. 6, and 3 is a transfer robot which is mounted with the work holding jig 2 and moves between the loading position X1 and the measurement position X2. A recess 2a for setting the work 1 is formed on the upper surface of the work holding jig 2, and a pair of reference pins 8 for supporting the work 1 from the left and right are provided. Further, as described later, a positioning mechanism that accurately holds and holds the workpiece holding jig 2 at a predetermined measurement position and a workpiece 1 that is pivotally supported by the workpiece holding jig 2 are clamped at the measurement position X2 of the transfer robot 3. Are provided with a swing mechanism 6 and a linear gauge (electric micrometer) 7 that are sandwiched from left and right by the finger 4a and rotated around the reference pin 8 by a drive motor 5. The linear gauge 7 is pulled out from the standby position to the measurement position by operating the elevating cylinder 7b.

Next, the detailed structure of the workpiece holding jig 2 is shown in FIGS. That is, the reference pin 8 is urged from behind by a spring 8a so as to protrude from the left and right into the recess 2a, and further, a pusher 9 urged by the spring 9a is provided at the rear end side of the recess 2a. . As shown in FIGS. 4A and 4B, the pusher 9 has the ear 1a (ear part) of the work 1 in a state where the reference pin 8 is inserted into the shaft hole 1b of the work 1 from the left and right and is pivotally supported. The tip of 1a is chamfered into a circular arc shape) from one direction, and the shaft hole 1b is pressed against the peripheral surface of the reference pin 8 to keep the center of rotation of the work 1 constant without backlash. Returning to FIG. 3, the work holding jig 2 is suspended between a pair of front and rear U-shaped columns 2 b erected on a carrier (movable element) of the transfer robot via compression coil springs 2 c arranged at four corners. The degree of freedom is displaceable.
Further, a positioning mechanism shown in FIGS. 5A to 5C is provided as means for locking and holding the workpiece holding jig 2 transported by the robot at the measurement position X2 (see FIG. 2). This positioning mechanism has a taper-shaped positioning hole 2d that is drilled on both the left and right sides of the workpiece holding jig 2 and expands downward, and an actuator (air cylinder) at the measurement position X2 of the transfer robot 3 facing the positioning hole 2d. And a taper-shaped positioning pin 10 which protrudes from below by the operation of 10a and fits into the positioning hole 2d.

Next, a method for measuring the rotational radius dimension R of the workpiece 1 performed using the measuring apparatus will be described. First, with respect to the workpiece holding jig 2 waiting at the loading position X1 of the transfer robot 2 shown in FIG. 2, the workpiece 1 extracted from the production line in the workpiece sampling inspection shown in FIG. The shaft hole 1b of the work 1 is fitted to the reference pin 8 as shown in FIG. In this set state, as described in FIG. 4, the work 1 is pushed by the pusher 9 so that the shaft hole 1 b is in contact with the reference pin 8 while being offset.
Subsequently, when the workpiece holding jig 2 reaches the measurement position X2 by carrying the carrying robot 1, the positioning pin 10 of the positioning mechanism described with reference to FIG. 5 is moved to the positioning hole as shown in FIG. The workpiece holding jig 2 is locked and held by being fitted into 2d. In this case, the work holding jig 2 is suspended by a compression coil spring 2c (see FIG. 3) and has a degree of freedom so that it can be displaced, and when the taber-like positioning pin 10 of the positioning mechanism is fitted into the positioning hole 2d. An alignment function works between the two, whereby the workpiece holding jig 2 is correctly latched and held at the measurement position defined by the positioning pin 10. Therefore, even if the transfer positioning accuracy of the transfer robot itself is not high, the work holding jig 2 is finally positioned and held at the predetermined measurement position X2 with high accuracy.

When the work holding jig 2 is positioned and held at the measurement position X2, the finger 4a of the clamp 4 of the swing mechanism 6 described in FIG. 2 is closed from the left and right, and the work 1 is moved as shown in FIG. While sandwiching from the left and right, the linear gauge 7 is moved from the standby position to the measurement position, and the probe 7 a is projected onto the tip movement locus of the workpiece 1. Subsequently, when the motor 5 in FIG. 2 is started and the workpiece 1 is rotated around the reference pin 8 via the clamp finker 4a as shown in FIG. 1C, the tip of the workpiece 1 is linearly moved in this swing stroke. The gauge 7 is brought into contact with the probe 7 a and pushed in, and a measurement value corresponding to the amount of movement of the probe is output from the linear gauge 7. Here, if the maximum output value of the linear gauge 7 is set to be held, the rotation radius dimension R of the workpiece can be obtained from this maximum output value.
In the swing stroke of the workpiece 1 described above, since the pusher 9 shown in FIG. 4 presses the shaft hole 1b of the workpiece against the reference pin 8 from a fixed direction, the rotation center of the workpiece does not change during the rotation. Thus, even when the workpiece 1 is replaced and repeatedly measured, the rotational radius dimension can always be measured with stable reproducibility under stable measurement conditions.

FIG. 4 is a flowchart of a method for measuring the radius of rotation of a workpiece according to the present invention, in which (a) shows a state where the workpiece is set on a holding jig, (b) shows a state immediately before the start of measurement at the measurement position, and (c) shows that the measurement is in progress. A diagram representing the state The top view which shows the structure arrangement | positioning of the whole measuring apparatus by the Example of this invention FIG. 2 is a plan view showing the detailed structure of the workpiece holding jig in FIG. It is a supplementary explanatory drawing of the state which set the work to the work holding jig of FIG. 3, (a) is a side view, (b) is the principal part enlarged view in (a). FIGS. 3A and 3B are positioning mechanism diagrams of a workpiece holding jig installed in the measuring apparatus of FIG. 2, and FIGS. 2A and 2B are end views showing a state before and after positioning at a measurement position, and FIG. Of positioning holes and positioning pins In the structure figure of the workpiece | work used as the measuring object of this invention, (a) and (b) are respectively a side view and a perspective view

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Work 1a Ear 1b Shaft hole 2 Work holding jig 2d Positioning hole 3 Transfer robot 4 Clamp 4a Clamp finger 5 Motor 6 Swing mechanism 7 Linear gauge 7a Probe 8 Reference pin 9 Pusher 10 Positioning mechanism positioning pin X1 Loading position X2 Measurement position

Claims (4)

A measuring method for measuring a rotational radius dimension from the center of the shaft hole to the tip of the workpiece for a workpiece to be a press-processed product having a shaft hole drilled in a bifurcated ear formed at one end, the shaft hole Is inserted into the measurement reference pin and the workpiece is set at the measurement position, and a linear gauge probe is placed on the rotational movement locus of the workpiece tip centered on the reference pin. A method for measuring a rotational radius dimension of a workpiece, wherein the rotational radius dimension of the workpiece is measured with a maximum value of a measurement output obtained from a linear gauge during the swing stroke while swinging around. A measuring apparatus for carrying out the measuring method according to claim 1, comprising: a workpiece holding jig for inserting a reference pin into a shaft hole of a workpiece from left and right to hold the workpiece in a predetermined direction; and the workpiece holding jig A transfer robot that moves between the loading position and the measurement position of the workpiece, a positioning mechanism that holds and holds the workpiece holding jig at a predetermined position at the measurement position, and clamps the workpiece to A swing mechanism that rotates around and a linear gauge that has a probe placed on the tip movement locus of the workpiece that rotates around the reference pin at the measurement position. The robot is transported to the measurement position, the workpiece is swung around the reference pin at this measurement position, and the tip of the workpiece is pressed against the linear gauge probe during the swing. Measuring device for a rotary radial dimension of the workpiece and measuring the rotation radius of the click. 3. The measuring device according to claim 2, wherein the workpiece holding jig is provided with a pusher that presses the workpiece from a fixed direction in a set state of the workpiece and presses the shaft hole against the reference pin. Measuring device. 3. The measuring apparatus according to claim 2, wherein a positioning mechanism for the workpiece holding jig is provided with a positioning hole on the workpiece holding jig and a positioning pin on the transfer robot side, and the positioning pin is inserted into the positioning hole at the measurement position of the transfer robot. An apparatus for measuring the radius of rotation of a workpiece, wherein the workpiece holding jig is positioned and held at a measurement position.

Images