JP3179269B2 - Surface runout measuring 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 measuring device capable of measuring a run-out of a molded rotary body such as a pulley, and more particularly to a surface run-out measuring device capable of measuring a center run-out of a molded rotary body.

[0002]

2. Description of the Related Art In general, an injection molded product is often used for a V pulley having a V-shaped groove formed on a circumferential surface used in a rotation transmission system of a tape recorder or the like. When a V-pulley is formed by injection molding, the V-pulley is molded using a pair of molds. Therefore, if the abutment state of the molds is slightly deviated, the molded product will have a core runout or a surface runout. .

The runout occurs when the center (axis) of the formed V-pulley is out of the designed value, and the runout occurs when the shaft center of the shaft is inclined. The center runout and surface runout are each within the allowable range (usually plus, minus 1
When it is not within the range of about 0 μm), it is a defective product. In order to manufacture a non-defective product, it is necessary to finely adjust the mold so that the core runout and the surface runout fall within an allowable range.

[0004] When the mold needs to be finely adjusted, for example, an abutting position of a mold (specifically, a slide core) or a core pin (not shown) for forming a shaft hole of a V pulley is provided. Planting position has been modified. In order to correct the planting position of the core pin, a nest (not shown) may be made again.

[0005] Prior to such mold adjustment, the center deviation measurement and the surface deviation measurement are performed. this house,
FIG. 13 shows an example of a conventional surface runout measuring apparatus 10.

The above-described injection-molded V-pulley is shown as the rotating body to be measured. Reference numeral 11 denotes a measurement base, and an upper surface 12 thereof serves as a mounting surface of the V pulley 20. The mounting surface 12 has a high flatness because it serves as a reference surface for measurement. An insertion hole 13 of a shaft 22 penetrated by the V pulley 20 is formed in a substantially central upper surface of the measurement base 11, and the shaft 22 is inserted and fixed into the insertion hole 13 as shown in the figure at the time of measuring a runout.

The V-pulley 20 is exemplified by a pulley body 21a and a boss 21b of a predetermined length, but the rotating body to be measured is not limited to this shape.

As shown in the figure, when measuring surface run-out, a V-pulley 20 having a shaft 22 penetrated is mounted so that the boss 21b side thereof is on the lower side. The distal end portion 25 of the runout detector 24 is disposed so as to lightly contact a part of the plane of the pulley body 21a, in this example, the outermost periphery of the plane.

In this state, data at a predetermined rotation position is measured while rotating the V pulley 20 in a fixed direction. When there is no surface deviation, the tip 25 of the surface deviation detector 24 always moves in the same plane. On the other hand, for example, when the shaft 22 is inclined by θ with respect to the reference rotation axis as shown in FIG. 13, the distal end portion 25 moves up and down according to the surface deflection angle θ. That is, the movement trajectories are not on the same plane.

FIG. 14 shows an example of the measurement result. A curve 23a is a locus when the flatness of the pulley body 21a is good and the axis is not inclined, that is, when there is no runout.
In this case, the locus is centered on the point O. In the case of a runout in which the flatness is good but the axis is inclined, the curve 23b is obtained, and the center point O 'is shifted from the reference point O. Curve 23c when the flatness is poor and the axis is also inclined.
The measurement result is as follows.

The measurement data such as the curve 23c is developed and illustrated as a curve La in FIG. The developed view of FIG. 15 is not developed from the measured data of the curve 23c and does not always match.

[0012]

When a V-pulley is formed by injection molding, as described above, a run-out or a run-out occurs due to the abutting state of the mold. As shown in FIG. Since the measurement is performed using the simple measurement device 10, it is not possible to obtain very accurate measurement data. This is because the measurement data is obtained while manually rotating the V-pulley 20, which is the measured rotating body, so that it becomes difficult to collect the measurement data from measurement points at regular intervals. During the measurement, it is conceivable that a hand or the like may come into contact with the V pulley 20, and this also indicates that the measurement data is not very accurate.

When the measurement result as shown in FIG. 15 is obtained, the position of the mold is corrected by the following method.

Assuming that the original data is a curve La, a shift of 20 μm in the y-axis (0 ° -180 °) direction, x
Since it is shifted by 10 μm in the axis (90 ° -270 °) direction, the correction (correction) as shown in FIG. 16 is performed. Since the correction amount is corrected by averaging a pair of molds, the correction amount of one mold is half of the figure.

When the y-axis is corrected by 10 μm, the curve L in FIG.
b and the curve L when corrected by 5 μm with respect to the x axis
It becomes like c. Therefore, the amount of correction depends on years of experience. In the mold repair method based on such an empirical rule, in addition to variations in the repair, the V pulley 20 within the standard cannot be formed unless the mold is repaired several times. There is an adverse effect such as doing.

When a rotating body such as a V-pulley is formed by injection molding, misalignment occurs in addition to the runout. Therefore, it is necessary to measure the misalignment as well as the misalignment with a measuring device. Therefore, it is preferable that both the run-out and the run-out can be measured by the same measuring device. For example, it would be very convenient if it was possible to measure the run-out and center run-out simply by attaching and detaching components.

Accordingly, the present invention has been made to solve such a conventional problem, and proposes a surface wobble measuring device capable of performing accurate surface wobble measurement.

[0018]

In order to solve the above-mentioned problems, in the present invention, sliders are mounted on a pair of bases so as to be able to move forward and backward, respectively, and V-shaped bearings are respectively mounted on these sliders. Attached and fixed, a shaft attached to the rotating body to be measured is passed over these V-shaped bearings, and detachable stoppers for fixing both ends of the slider and the shaft are provided. While the rotating body for measurement is rotated in a state where the rotating body for measurement is in contact with a part of the plane of the rotating body for measurement, the rotating body for measurement is measured with the rotating body for measurement. It is characterized by doing so.

[0019]

When there is a runout as shown in FIG. 13, the tip 25 of the detector 24 moves up and down with respect to a reference plane (a reference plane when the runout is zero). FIG. 1 shows the runout of FIG.
°, the shaft 22 and the slider 34,
35 are fixed by stoppers 50A and 50B,
If the tip 25 of the detector 24 is brought into contact with the measurement surface, the measurement element 25 moves left and right due to surface shake, and measurement data corresponding to the surface shake can be obtained.

A mold correction amount is calculated from the measurement data thus obtained in accordance with the processing flow shown in FIG. In this case, a center of gravity O '(referred to as a measured center of gravity) based on the measured data is obtained from the obtained measured data, and a correction value for correcting the center of gravity O' to the standard center of gravity O is obtained. At this time, the correction value is corrected using the radius R of the V pulley 20 and the height H including the boss 21b.

When the stoppers 50A and 50B are removed, the slider 35 becomes free. If the tip 25 of the detector 24 is brought into contact with the V-shaped groove 21 as shown in FIG. it can. This is because the tip 25 moves up and down when the V-pulley 20 is out of alignment.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A case where an example of a runout measuring apparatus according to the present invention is applied to a runout measurement of a V-pulley will be described in detail with reference to the drawings. According to the present invention, the same measuring device is configured to be able to measure both surface runout and center runout.

FIG. 1 is a plan view showing an example of a surface shake measuring apparatus 1 according to the present invention, which is a top view and FIG. 3 which is a partially sectional side view. To be described with reference to this embodiment, the surface runout measuring apparatus 1 is made of brass or steel for all its components. However, synthetic resins such as so-called engineering plastics may be used as long as conditions such as processing accuracy, assembly accuracy, and expansion and contraction due to temperature can be satisfied.

The surface runout measuring apparatus 1 has a pair of rectangular bases (tables) 30 and 31 which are arranged so as to face each other at a predetermined distance. Rails 32, 33 having a rectangular cross section parallel to the facing direction are attached and fixed to the holding plates 32a, 32b, 33a, 33b and well-known means (not shown) such as screws (see FIG. 1).

Sliders 34 and 35 are mounted on the rails 32 and 33 by using the rails as guides. The cross sections of the sliders 34 and 35 are inverted U as shown in FIG.
A rail-shaped piece, a rail 32, 33 and a slider 3
The friction coefficient between the sliders 34, 35 is designed to be very small, and even if a slight force is applied to the sliders 34, 35, the sliders 34, 35 in the pressing direction (the left-right direction in the figure).
35 slides.

The auxiliary members 3 are provided on the upper surfaces of the sliders 34 and 35.
6, bearings 38, 39 each having a V-shaped groove as shown in FIG. This bearing 38,3
A shaft 22 inserted through a V pulley 20, which is a rotating body to be measured, as shown in FIG. An auxiliary pulley 44 for rotating and driving the V pulley 20 is further inserted through the shaft 22 and fixed.

As shown in FIG. 1, a drive motor 40 is fixed to one of the bases 30, and a shaft pulley 42 is mounted on a rotary shaft 41 thereof. Is attached to the V-pulley 20 so that the V-pulley 20 is driven to rotate at a predetermined speed during the run-out measurement.

As will be described later, when there are many measurement points on the V-pulley 20, the rotation speed of the V-pulley 20 needs to be reduced, so that the auxiliary pulley 44 preferably has a larger diameter.

The pair of bases 30 and 31 are connected to each other by a holding plate 46 in order to keep the facing distance between the bases 30 and 31 constant.
The size of the misalignment measuring device 1 is determined according to the size of the member to be measured.

As described above, the shaft 22 having a predetermined length is attached to the V-pulley 20, which is a member to be measured, and both ends of the shaft 22 are fixed, and the sliders 34, 3 are fixed.
Stoppers 50 (50A, 50B) for fixing 5 are arranged on rails 32, 33, respectively. Stopper 50
A and 50B are configured to be detachable, and their shapes are selected as shown in FIG. 4 according to the components of the measuring device.

As shown in FIG. 4, a substantially inverted L-shaped main body 51 is provided.
On the other hand, a columnar abutment 52 that is in contact with the shaft 22 is attached to the tip. The abutment 52 is internally supported by a coil spring or the like so as to be able to advance and retreat to some extent. The abutment 52 can be omitted. in this case,
The end of the main body 51 directly presses the shaft 22.

The lower portion of the main body 51 is formed with a step 54 matching the side surface shape of the slider 34 and the auxiliary member 36.
The length of the lower part of 1 is selected just as long as the presser plate 32a.

Since the engaging recess 55 for engaging with the rail 32 is formed on the lower surface of the main body, if the main body 51 is mounted so as to be engaged with the rail 32, the sliders 34 and 35 will be higher than those shown in the figure. Since it cannot move to the right side (not shown), the sliders 34 and 35 and the shaft 22 can be fixed to the state shown in FIG.

The runout is measured with the pair of stoppers 50A and 50B used. Therefore, the shaft 22 inserted through the V-pulley 20, which is the rotating body to be measured, is inserted between the bearings 38 and 39 as shown in FIG. A rotational force is transmitted to the auxiliary pulley 44 from the drive motor 40.

The V-pulley 20 is rotated at a predetermined speed with the tip 25 of the detector 24 as shown in FIG. 13 contacting the side surface of the V-pulley main body 21a, in this example, the outermost peripheral side of the side surface. Of the V-pulley 20 is measured. When there is no surface deviation, the movement trajectory of the distal end portion 25 does not deviate from the reference plane (vertical plane in the figure). If there is a run-out, the movement trajectory of the tip end portion 25 of the detector 24 fluctuates left and right with respect to the reference plane. Therefore, it is possible to know the degree of the run-out using the measurement data at that time.

When it is desired to use the measuring apparatus 1 also for the measurement of misalignment, a pair of stoppers 50 which are detachably configured
Remove A and 50B before use. Then, as shown in FIG. 5, the pair of sliders 34 and 35 is free, and the shaft 22 is also free. The distal end 25 of the detector 24 is arranged so as to abut the V-shaped groove 21 as shown in the figure.

If there is any misalignment, the tip portion 25 moves up and down in the same reference plane (vertical plane passing through the V-shaped groove 21) in accordance with the amount of misalignment. Can be accurately measured.

The pair of sliders 34, 35 is
The reason why they are made free in the axial direction is to remove the influence of surface deviation at the time of center deviation measurement. This will be described below.

When there is a run-out along with the center run-out, the tip 25 of the detector 24 is moved to the bottom p of the V-shaped groove 21 in accordance with the run-out.
Acts away from. When the tip 25 of the detector 24 is separated from the bottom p of the V-shaped groove 21,
Of the load (pressing force) from the detector 24 acting on the shaft 22, the shaft 22 tends to move in the direction of the component force due to the component force parallel to the shaft 22. Shaft 22 and shaft 2
The bearings 38 and 39 on which the belt 2 is mounted are substantially integrated in the axial direction by the force of the belt 47 pulling the auxiliary pulley 44 downward, and the component force on the shaft 22 is reduced by the sliders 34 and 35.
Is transmitted to Since the sliders 34 and 35 are free in the axial direction, the sliders 34 and 35 slide in the same direction as the component force until the component force becomes zero.

Due to this sliding operation, the tip 25 of the detector 24 faces the bottom p of the V-shaped groove 21 and is at a position where the component force becomes zero when it reaches the bottom p, whereby the runout becomes zero. . Even when the pair of sliders 34 and 35 are set in a free state as described above, the tip 25 of the detector 24 always remains at the bottom p of the V-shaped groove 21 even if there is a run-out.
In this way, the influence of the surface deviation on the measurement of the center deviation can be eliminated.

Next, a specific example of the surface shake measurement will be described. V pulley 2 with boss 21b as shown in FIG.
When 0 is the rotating body to be measured and there is run-out,
This means that the axis q 'is shifted from the reference axis q by, for example, θ. At this time, the deviation from the fixed point r when the point r at the lower center of the boss 21b is regarded as the fixed point is measured as the deviation.

Therefore, as shown in FIG. 7, the actual axis x 'is θ with respect to a reference plane (shown by a solid line) orthogonal to the reference axis q.
If it is only tilted, a plane (shown by a dashed line) orthogonal to the axis q ′ becomes a measurement plane, and the tip 25 comes into contact with this measurement plane to perform data measurement. The amount that is actually inclined with respect to this measured amount ΔL is ΔM. The correction amount when correcting the mold in its x-axis and y-axis directions is not ΔL but ΔM
It is. Therefore, the correction amount ΔM is obtained in consideration of the radius R of the V pulley body 21a and the length H of the boss 21b. That is, since ΔM: ΔL = H: R (1), ΔM = (H / R) ΔL (2)

When viewing FIG. 7 from above, it is possible to know in which direction the axis q 'is inclined in the x and y axes and how much. FIG. 8 shows a top view thereof.

The center O 'shown in FIG. 8 is obtained by calculating the center of gravity (measured center of gravity) from the actually measured data. The measured center of gravity can be obtained as follows.
First, as shown in FIG. 9, in this example, 500 measurement points are determined, and measurement data is obtained from each measurement point. Two axes (x and y axes) of the V pulley 20 are obtained from these measurement data. For example, the measurement point having the largest surface deviation is defined as the x-axis (0 ° -1
80 °).

Next, in this example, the center of gravity is calculated using the measurement data at every 30 ° with reference to the 0 ° of the x-axis. If the angle is 30 °, a dodecagonal figure can be obtained over the entire circumference, so the area center of gravity obtained by calculation from these polygons is defined as the point O ′ of the measured center of gravity.

In the above description, the reference x-axis and y-axis were obtained using 500 points of measurement data, but the measurement center of gravity can be obtained without calculating the reference axis again. In this case, it is also possible to measure only 12 points used for calculating the measured center of gravity. In such a case, the axis passing through the first measurement point is set as the reference axis (0
° -180 °).
The above numerical values are merely examples. The number of measurement points for obtaining the measured center of gravity is also an example, and the greater the number of points for calculating the center of gravity, the better the calculation accuracy. However, it is inevitable that the calculation time for this will be long,
The number of measurement points is set in consideration of both. Experiments have confirmed that sufficient accuracy can be obtained even with the number of measurement points described above.

The center O 'indicating the measured center of gravity obtained in this way is moved to the center O when the ideal V pulley having zero runout is measured, so that the runout of the V pulley 20 is obtained. Can be modified. When O 'is moved to O, the line segment OO' becomes parallel to the line segment AA ', so that the amount to be actually moved, that is, the mold correction amount ΔM is ΔM = {(X ² + Y ² ) ^1/2 }. (H / R) = line segment AA ′ × (H / R) = line segment OO ′ × (H / R) (3) ∠CO′O is: ∠CO′O = tan ⁻¹ (X / Y) (4) ∴∠A'Ab = φ-tan ^-1 (X / Y) (5) When the mold correction amount is a minute value of about 0.05 mm or less. The mold correction amount (approximate value) of the line segment AB is: line segment AB = line segment AA'COS {φ-tan ^-1 (X / Y)} = {(X ² + Y ² ) ^1/2 } COS {φ−tan ⁻¹ (X / Y)} · (H / R) (6) The actual measurement value (measurement data) at the angle φ is represented by S = line segment OA,
Assuming that the predicted value after moving the center from O ′ to O is S ′, S ′ = S + line segment AB = S + {(X ² + Y ² ) ^1/2 } · COS ｛φ−tan ⁻¹ (X / Y )｝ · (H / R) (7) When the difference between the predicted value S 'and the value of an ideal V-pulley having no surface run-out is within an allowable value (when the values are approximately similar), the above-described mold correction amount ΔM is used as it is as the correction value. Used as However, if the circle drawn by the measurement points shown in FIG. 9 is close to a perfect circle, the runout can be minimized by moving O ′ to O. However, since O ′ actually shows a complicated shape, O ′ is replaced by O. Even if it moves to, the runout is not always minimized.

When the value is out of the allowable value, the correction value as shown in FIG. 10 (within several μm, in this example, 1 μm, −1 μm)
m), the center O 'is forcibly shifted in the x-axis and y-axis directions, and the above-described processing is performed. The center at which the value is closest to the ideal value is measured by the V pulley 20 Used as the center of gravity, mold correction amount O at that time
O 'is calculated.

FIG. 11 shows an example of a circuit system of the measuring apparatus 1 used for measuring the surface shake. Measurement data detected by the detector 24 is supplied to an A / D converter 62 via an amplifier 61. Is converted to a digital signal having a predetermined number of bits, and the converted measurement data is supplied to the CPU 63, and the x-axis (0 ° -180 °) is used by using a surface deviation measurement program including a step measurement provided therein. , The calculation of the y-axis (90 ° -270 °), the calculation of the surface shake correction amount, and the like are automatically executed.

A rotation control signal for the drive motor 40 is generated from the CPU 63 via the driver 66. The rotation speed of the V pulley 20 and the like are determined by the rotation control signal. In synchronization with this rotation control signal, the timing of taking in the measurement data from the detector 24 at a predetermined measurement point is further determined.

Reference numeral 64 denotes a display unit (CRT, liquid crystal element, etc.) for displaying measurement data and calculation results, and 65 denotes a printer for printing such data.

The above-described surface shake correction amount and the like are stored in a memory (RAM or the like) built in the CPU 63, and are used as a mold correction amount or a correction amount for forming a mold.

FIG. 12 is an example of a flowchart showing a processing procedure for calculating the surface shake correction amount.

When the above-described processing program is started,
This is a process for inputting measurement data (step 71), and when this is completed, a process for calculating the measurement center of gravity is performed (step 7).
2). After calculating the center O 'indicating the measurement center of gravity, the value (new measurement data) of the destination (point B) of the actual measurement point when the center O' is moved to the center O serving as the ideal center of gravity is calculated ( Step 73). The calculation of the point B of the movement destination may be performed for all the measurement data, but may be simply performed for only the 12-point measurement data used when obtaining the measurement center of gravity.

Next, the comparison between the data when the runout is zero and the new measurement data is performed between the same actual measurement points (step 74). If the comparison result indicates that the two data are the same or within the range of an allowable value (an extremely approximate value), the calculated value of the center O ', which is the measured center of gravity, is used as it is as the center of rotation (step 75), and the optimal center of gravity A surface shake correction amount OO 'is calculated from O' and the ideal center of gravity O. Center O '
From the inclinations X and Y in the x and y axis directions corresponding to the correction amount OO '.

On the other hand, when the comparison result is not within the range of the allowable value, it is determined that there is an error in the calculated center of gravity, and the measured center of gravity is corrected (step 76). As shown in FIG. 10, the center of gravity of the measured center of gravity is shifted to points O1 'to O8' within the range of plus or minus 1 .mu.m, and data from that position to point B is converted from the measured data and converted. New measurement data (total 8 types) is obtained (step 76).

A comparison is made between these eight types of new measurement data and the above-described data at the time of zero runout, and the center (O1 'to O8') relating to the new measurement data having the minimum error among them is obtained. Is used as the optimal center of gravity. Using this optimum center of gravity, a surface shake correction amount OO 'is calculated (step 78).

In the embodiment described above, the present invention is applied to the V pulley 2
Although it was applied to the runout measurement of 0, it can be easily understood that the rotating body to be measured can be applied not only to the rotating body other than the V pulley but also to the rotating body used in the tape recorder and the like.

[0059]

As described above, the surface wobble measuring apparatus according to the present invention measures the surface wobble described above in which the slider to which the rotating body to be measured is inserted is fixed.

According to this, since the runout of the rotating body to be measured can be accurately measured, the mold position can be accurately corrected as long as the measurement data is used. Also, in this configuration, the measuring device can also be used as a device for measuring the misalignment by simply removing the stopper for fixing the slider from the device, so that the measuring device of the dual configuration can be realized without increasing the number of parts. Have. In this case, even if there is a run-out, the run-out can be measured in a state where the run-out is corrected to be zero, so that the run-out of the rotating body to be measured must be measured without being affected by the run-out. Can also.
Therefore, the present invention has a feature that the accuracy of the molded product to be calibrated is greatly improved.

As described above, the present invention is extremely suitable for use in measuring the runout of a pulley or other rotating body of a tape recorder in which the precision of a molded product is required to be relatively strict.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a surface shake measuring device that also serves as a center shake measurement according to the present invention.

FIG. 2 is a top view of FIG.

FIG. 3 is a side view in which a part of FIG. 1 is sectioned.

FIG. 4 is a perspective view of a stopper.

FIG. 5 is a plan view when used as a misalignment measuring device.

FIG. 6 is a diagram showing an example of surface shake measurement.

FIG. 7 is a diagram illustrating an example of surface shake measurement.

FIG. 8 is a diagram illustrating a specific example of calculating a surface shake correction amount.

FIG. 9 is a diagram showing a relationship between surface shake measurement data and a measurement center of gravity O ′.

FIG. 10 is a diagram showing an example of correction of the position of the measured center of gravity.

FIG. 11 is a system diagram showing an example of a circuit system of the surface shake measuring device.

FIG. 12 is a flowchart illustrating an example of surface shake measurement.

FIG. 13 is an explanatory view of a conventional surface shake measuring device.

FIG. 14 is a diagram showing a typical surface deviation.

FIG. 15 is a diagram showing surface shake measurement.

FIG. 16 is a diagram illustrating a direction of correction of a surface shake.

[Explanation of symbols]

 1 Surface runout measuring device 20 V pulley 22 Shaft 34, 35 Slider 38, 39 V-shaped grooved bearing 50 (50A, 50B) Stopper

Continuation of the front page (56) References JP-A 63-99204 (JP, U) JP-A 48-84254 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01B 5 / 00-5/30 G01B 21/00-21/32

Claims (1)

(57) [Claims] 1. A slider is mounted on a pair of bases so as to be able to move forward and backward, and V-shaped bearings are respectively mounted and fixed on these sliders. The V-shaped bearings are mounted on the rotating body to be measured. The slider provided is provided with detachable stoppers for fixing both ends of the slider and the shaft. During the measurement of the run-out, the run-out detector is applied to a part of the plane of the rotating body to be measured. A surface shake measuring device, wherein the surface shake detector measures the surface shake of the measured rotary body while rotating the measured rotary body in the contact state.