JPS5819441Y2 - Zero-adjustable dial gauge misreading prevention device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing misreading by zero adjustment of a one-rotation type dial gauge, which has graduations in a predetermined range on the periphery of a disc-shaped scale plate.

Dial gauges usually have a pointer that rotates several times on a disc-shaped scale plate.

However, even with dial gauges where the pointer rotates several times, in actual use, in most cases, it is used for comparative measurements within the range where the pointer rotates once. Ta.

In addition, in such a dial gauge, the pointer may point to the same position on the scale plate several times, so
There was a problem in that it was easy to misunderstand how many revolutions the pointer had made, making it easy to set mistakes or misread measurement values.

Therefore, when such a dial gauge is used to measure the dimensions of a workpiece during processing, there is a possibility that a processing error may occur.

Conventionally, in order to solve this problem, the pointer was made to rotate within a certain angle within one rotation, and the periphery of the scale plate was designed to divide the same angular range as the pointer's rotation angle into thirds. A dial gauge has been proposed that has a forward scale and a reverse scale, with non-scale portions for both scales.

However, in this dial gauge, the scale plate is provided with respect to the inner frame so that it can be rotated without limit in the circumferential direction, and by rotating this scale plate in the circumferential direction, the pointer and scale are Since the pointer is aligned with the zero point on the plate, depending on the zero adjustment position at the time of setting, the pointer may go beyond the non-scale part of the scale plate and reach the forward or reverse scale. There was a problem that the guideline would indicate a value different from the actual value.

Furthermore, since there are various types of people who measure, and the position in which a dial gauge is used is determined by the shape of the object to be measured, etc., it is necessary to zero the scale when the allowable amount of rotation of the pointer is small. Often.

In this case, even though the spindle is moving during measurement, the pointer may reach its limit and true measurement may not be performed, and the measurer may not notice.

By nature, when measuring high-precision parts, the error is small;
This is because it is assumed that there is almost no fluctuation in the guideline.

On the other hand, in the above-mentioned zero focusing, if the pointer rotates significantly, for example, to the right, the pointer passes through the apparently upward, non-scale portion and reaches the left scale portion on the opposite side.

In this case, the pointer generally moves at a high speed, and the direction of rotation cannot be visually confirmed in many cases, and the measurer must be aware that if the dial gauge has a non-scale section, the pointer will move beyond the non-scale section to the opposite side. There was a problem in that the driver did not think that it was actually a counterclockwise rotation, but misunderstood it as if it were currently being instructed as a counterclockwise rotation.

The present invention solves these problems by providing a device for preventing misreading of rotary dial gauges.The purpose of this invention is to provide a device for preventing misreading of rotary dial gauges. It is characterized by a set rotation range.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In Figures 1 and 2, 1 is a cylindrical inner frame, 2 is an inner frame 1
An annular retaining groove 3 formed on the outer circumferential surface is an outer frame holder made of synthetic resin that is fitted into the retaining groove 2 .

As shown in FIG. 1, the outer frame receiver 3 is formed into a partially cut-out circular shape (C-shape), with a screw-retaining groove 4 formed in the center thereof, and screw-retaining grooves 4 at both ends thereof. Grooves 5 and 6 are formed respectively.

The engagement groove 4 is located at the corner 3a of the outer frame receiver 3 as shown in FIG.
is formed in a V-shape, and the bottom part 4a is the outer frame receiver 3.
It is inclined from the upper surface 3b toward the outer peripheral surface 3C.

The engaging groove 5.degree.6 is formed in a rectangular shape at the corner 3a, and the bottom thereof is inclined from the upper surface 3b of the outer frame receiver 3 toward the outer circumferential surface 3C, as shown in FIG.

Reference numeral 7 denotes an annular aluminum alloy outer frame, which is loosely fitted around the outer periphery of the inner frame 1.

Set screws 8, 9.degree. 10 are screwed into the outer frame 7, respectively.

The tip of the set screw 8 comes into contact with the V-shaped engagement groove 4 to eliminate play in the circumferential direction of the outer frame receiver 3 and play in the radial direction at the center of the outer frame receiver 3. There is.

The tip of the set screw 10 comes into contact with the bottom of the engagement groove 6, so that play in the radial direction of the end of the outer frame receiver 3 can be removed.

In FIG. 2, 11 is a circular scale plate fixed within the outer frame 7, 12 is a disc-shaped dial plate attached to the inner frame 1 side, and 13 is a transparent cover attached to the outer frame 7. The scale plate 11 and the dial plate 12 can be rotated relative to each other.

In addition, in this embodiment, an example was shown in which the dial 12 was provided separately from the scale plate 11 and the dial 12 was attached to the inner frame 1, but the dial 12 does not necessarily need to be provided.
Alternatively, only a disc-shaped scale plate 11' as shown in FIG. 5 may be mounted inside the outer frame 7.

The peripheral edge of the scale plate 11' is provided with a zero base line 14, a positive scale 15 extending clockwise from the zero base line 14, and a reverse scale 16 extending counterclockwise from the zero base line 14.

The regular scale 15 is composed of a scale line 15a and numbers 15b attached at regular intervals along the scale line 15a, and the number 1
The values of 5b gradually increase in the clockwise direction.

The reverse scale 16 is composed of a scale line 16a and numbers 16b placed at regular intervals along the scale line 16a, and the numbers 16b gradually increase in value in the counterclockwise direction.

Reference numeral 17 denotes a non-scale portion provided within the angle θ on the peripheral edge of the scale plate 11', and is located between the normal scale 15 and the reverse scale 16.

In addition, the normal scale 15 and the reverse scale 16 are provided with equal divisions of, for example, 50 scales within 180 degrees.

The scale plate 11 has scales 15 and 16 attached to the scale plate 11'.
The same scale (not shown) is attached.

A gap 18 is formed between both ends of the outer frame receiver 3.

A rotation regulating pin 19 attached to the inner frame 1 is loosely fitted into this gap 18 .

The outer frame 7 can be rotated around the center point A of the inner frame 1 at an angle θ3+θ4 within the range excluding the angle θ6 of the rotation regulating pin 19 from the angle θ5 of the gap 18, and this rotatable angle θ
3 is equal to or smaller than the angle θ1 between position B where the needle rotates most counterclockwise and stops and the end of the scale, and θ4 is the angle between position C where the needle rotates most clockwise and stops and the end E of the scale. It is set to be equal to or smaller than the angle θ2 between them.

The center of the non-scale portion 17 is located 180° from the zero base line 14, and the broken line 20 connecting the center of the non-scale portion 17 and the zero base line 14 indicates that the rotation regulating pin 19 is located at the center of the gap 18. It is provided so as to be parallel to the axis of the spindle 21.

The spindle 21 is slidably held by the inner frame 1.

The pointer 22 shown in FIG. 5 is linked to the spindle 21 via a gear enlarging mechanism (not shown), and rotates when the spindle 21 is displaced in its axial direction.
It is designed not to rotate more than one rotation.

Further, the spindle 21 is biased toward a probe (not shown) (downward side in FIG. 1) by a return spring (not shown).

When using a dial gauge with this configuration,
Attach the dial gauge to a holder (not shown), and set the dial gauge to a standard height by applying the probe of the dial gauge to a block gauge or the like.

In this case, the pointer 22 is placed in such a position that the spindle 21 can move the pointer 22 approximately equally in both left and right directions when the pointer 22 indicates the zero base line 14.

When setting the dial gauge in this way, the pointer 22
If it does not match the zero base line 14 and is slightly deviated, loosen the setscrews 9 and 10 and rotate the outer frame 7 relative to the inner frame 1 to rotate the scale plate 11 or 11'. to align the pointer 22 with the zero base line 14.

In this case, even if the scale plate 11 or 11' is rotated to the maximum, the scales 15 and 16 will not fall within the angle α around point A, that is, the angle θ1+θ2 subtracted from the angle θ of the non-scale portion 17. There isn't.

Note that this range is within α/2 from left to right with the axis of the spindle 21 as the center.

The pointer 22 does not rotate past point B or point 0 on the non-scale portion side, and even if the pointer 22 rotates clockwise to the maximum, the pointer 22 will not rotate beyond the normal scale 15 or beyond the non-scale portion 17. Even if the pointer 22 rotates counterclockwise to the maximum, the pointer 22 will not indicate the reverse scale 16.
The normal scale 15 is not indicated above or beyond the non-scale portion 17.

Note that the pointer 22 is designed to rotate clockwise when the spindle 21 is displaced upward in FIG.

In the embodiment described above, the outer frame 7 is allowed to rotate within a certain range by the rotation regulating pin 19 protruding from the inner frame 1 and the outer frame receiver 3, but the rotation of the outer frame 7 is restricted. The configuration is not necessarily limited to such a configuration, but a notch 23 extending in the circumferential direction is provided in the outer frame 7 as shown in FIG. The rotation of the outer frame 7 may be restricted by the configuration in which the movement restriction pin 24 is positioned.

As explained above, the present invention allows zero adjustment by rotating the scale plate, but the scale plate only rotates within a certain range, and the pointer does not rotate more than one revolution. In addition, even if the pointer is rotated clockwise, the pointer will not rotate beyond the non-scale area, so if you zero the dial gauge in any position, you will be able to find the zero point. The pointer can be rotated approximately equally in both left and right directions about the center, and it is possible to completely prevent misreading of measured values as in conventional dial gauges.

In addition, since the peripheral edge of the scale plate has a positive scale that goes clockwise from the zero base line and a reverse scale that goes counterclockwise,
There is an advantage in that it is possible to easily measure how much the object to be measured is larger or smaller than the reference value.

[Brief explanation of the drawing]

Fig. 1 is a partial sectional view of a dial gauge showing an embodiment of the present invention, Fig. 2 is a sectional view taken along the line II--II of Fig. 1, and Fig.
Figure 4 is an enlarged perspective view of the retaining groove provided in the outer frame holder of Figure 1, and Figure 5 is a plan view showing another example of the scale plate used in the embodiment of the present invention in relation to the pointer. 6 are partial perspective views of a dial gauge showing another embodiment of the present invention. 1...Inner frame, 11.11'...Scale plate, 15...Positive scale, 14...Zero base line, 17... Non-scale portion, 16... Reverse scale, 22... Pointer, 21... Spindle.

Claims (1)

[Scope of utility model registration request] In a dial gauge in which the amount of displacement of a spindle held in an inner frame is read by a pointer linked to the spindle and a scale on the periphery of a circular scale plate held in the inner frame so as to be rotationally adjustable in the circumferential direction. , the scale on the periphery of the scale plate is divided into a normal scale and a reverse scale, and between the normal scale and the reverse scale (,:
' A non-scale portion provided, the rotation of the scale plate is restricted relative to the inner frame so that it can rotate in the circumferential direction within the range of the non-scale portion, and the pointer is configured to rotate beyond the non-scale portion. An error reading prevention device for a zero-adjustable dial gauge, characterized in that rotation of the pointer is restricted so that the pointer does not rotate.