JPH0620962Y2 - Angle measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to an angle measuring device that can easily measure an angle even if an object cannot be directly measured by applying a protractor.

(Prior Art) For example, in the case of measuring the angle of the V-shaped groove in a square block having a V-shaped groove, if the end of the V-shaped groove appears on the side surface of the block. By applying a protractor to the side surface of the block, the angle of the V-shaped groove can be directly measured.

However, in the case of a V-shaped hole, it is not possible to measure the angle of the V-hole directly using a protractor, because the end of the V-hole no longer appears on the side of the block.

(Problems to be Solved by the Invention) As described above, as a conventional angle measuring device, there is a protractor, but this cannot measure when measuring the angle of a V-shaped hole. There has been a demand for the appearance of a simple angle measuring device that can measure the angle even in the case of a letter-shaped hole.

Therefore, an object of the present invention is to provide a simple angle measuring device that can easily measure an object to be measured whose angle is difficult to measure with a protractor.

[Configuration of Device] (Means for Solving the Problem) The angle measuring device of the present invention is rotatably connected by a shaft,
A pair of measurement pieces having objective contact surfaces that are applied to the two surfaces of the object to be measured, and a pair of these measurement pieces, which are located on a straight line that passes through the center of the axis and is orthogonal to each objective contact surface. It is characterized in that it comprises a pair of gauge points provided, and the angle formed by the two surfaces of the measuring object is obtained from the distance between the gauge points.

(Operation) The opening angles of both measurement pieces are adjusted, and their object contact surfaces are applied to the two surfaces of the measurement object. Then, while maintaining the opening angle, both measurement pieces are separated from the object, the distance between the gauge points of both measurement pieces is measured, and the angle formed by the two surfaces of the measurement object is obtained from the distance.

The principle by which the angle can be obtained from the distance between the gauge marks is as follows.

Now, in FIG. 3, the angle between the two surfaces to be measured is θ, and the straight lines indicated by A and B represent the two surfaces, and at the same time, the object contact surfaces of the pair of measurement pieces applied to these two surfaces. And C is the center of rotation (center of the shaft) of the pair of measurement pieces. Further, when the intersections of the perpendicular D drawn from the point C to the straight lines A and B and the straight lines A and B are P and Q, the points P and Q are the gauge points of the pair of measurement pieces.

When the point C and the intersection E between the straight lines A and B are connected by the straight line F, the line segment CE and the line segment PQ are orthogonal to each other at the intersection point M.
Considering the right-angled triangle CQE and the right-angled triangle CMQ, it is understood that the angle α formed by the line segment CQ and the line segment MQ is 1/2 of the calculated angle θ, because both right-angled triangles are similar figures. It When the length of the line segment CQ is L and the length of the line segment PQ is, the angle α is COS.
^Since it is expressed by ⁻¹ [(/ 2) ÷ L], the obtained angle is θ = 2 × COS ⁻¹ [(/ 2) ÷ L] (1). In this case, L is the distance (constant) from the center of the axis of the angle measuring device to the object contact surface of the measurement piece, and is the distance between the gauge points of both measurement pieces, so that the gauge points of the pair of measurement pieces are eventually The angle formed by the two surfaces can be determined from the distance between the parts.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

First, in FIG. 1, 1 and 2 are a pair of measuring pieces, which are of the same size and are symmetrical to each other.
At both ends of 2a, short connecting side portions 1b and 2b and relatively long measuring side portions 1c and 2c are extended in opposite directions. Both of these measuring pieces 1 and 2 have a measuring side 1
The tip ends of c and 2c are directed outward, and they are rotatably connected by the shaft 3 at the connecting piece portions 1b and 2b.

The lower surfaces of the measurement sides 1c and 2c of the two measurement pieces 1 and 2 shown in the figure are objective contact surfaces 1d and 2d which are applied to the measurement object.
It is said that. Further, the objective contact surface 1 passes through the center of the shaft 3.
When a straight line D orthogonal to d and 2d is considered, the inner acute-angled edge of both end edges of the objective contact surfaces 1d and 2d is located on the straight line. The edges are marked points 1e and 2e.

Next, the case where the angle is measured by the angle measuring device configured as described above will be described. The measurement object 4 shown in FIG.
A V-shaped recess 5 is formed, and the recess 5
The angle formed by the surfaces 5a and 5b shall be measured.

First, both measurement pieces 1 and 2 are put into the recess 5, and both measurement pieces 1 and 2 are
2, the object contact surfaces 1d,
2d is applied to the two surfaces 5a and 5b of the recess 5, respectively. After that, the measurement pieces 1 and 2 are separated from the recess 5, and the distance between the gauge points 1e and 2e is measured with a caliper or a micrometer. In this case, since the acute-angled edges of the measurement pieces 1 and 2 are the gauge point portions 1e and 2e, it is easy to apply a caliper or a micrometer probe, and the distance can be accurately measured.

In this way, the angle θ is calculated from the equation (1) based on the distance between the two control points 1e and 2e (the distance between the center of the axis 3 and the control points 1e and 2e is known). ). In the case of the present embodiment, a conversion table showing the relationship between the distance between the control points 1e and 2e and the angle is provided in advance. A part of this conversion table is as follows, for example.

If the distance between the gauge points 1e and 2e is 20.00 mm, the angle is 156.926 degrees from the above conversion table. In the case of the angle measuring device of the present invention, the gauge point portion 1 is different from the angle change.
In the range in which the change in the distance between e and 2e is large, particularly high measurement accuracy can be obtained, but as can be understood from the above formula (1), in the range of 90 ° to 180 °, especially in the vicinity of 180 °, I can say that. Actually, in the present embodiment, as exemplified in the above table, in the vicinity of 156 °, the change of the angle of 1 ° is represented as the change of the distance between the gauge points 1e and 2e of 1 mm, so that the measurement is relatively accurate. it can.

As described above, according to the present embodiment, as long as the measuring pieces 1 and 2 can be inserted, even if the angle measuring portion is a hole, as shown in FIG. Even if 6 has a flat bottom surface 6a and the two surfaces 6b and 6c do not intersect in a V shape, measurement is possible and the applicable range is widened.

The shape of the measurement piece is not limited to the substantially Z-shape as in the above-mentioned embodiment, and can be appropriately changed in practice. In this case, as long as a point located on a straight line corresponding to the straight line D in FIG. 1 can be attached to the surface of the measurement piece, the point may be used as the reference mark portion.

[Effect of the Invention] As is apparent from the above description, according to the angle measuring device of the present invention, if a pair of measuring pieces can be inserted, even if a protractor cannot measure, for example, a hole, the angle can be easily measured. Since it has a simple structure in which a pair of measuring pieces are rotatably connected by a shaft, it can be provided at a low cost.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention. FIG. 1 is a front view showing an angle measurement state, and FIG. 2 is a front view showing a measurement state of an object to be measured different from FIG. FIG. 3 is a diagram for explaining the principle of the present invention. In the figure, 1 and 2 are measuring pieces, 1d and 2d are objective contact, 1e,
2e is a gauge point part.

Claims (1)

[Scope of utility model registration request] 1. A pair of measurements for measuring an angle formed by two surfaces of an object to be measured, the pair of objects having an objective contact surface rotatably connected by a shaft and applied to the two surfaces of the object to be measured. And a pair of gauge points provided on each of the measurement pieces on the straight line that passes through the center of the axis and is orthogonal to each objective contact surface, depending on the distance between the gauge points. An angle measuring device characterized in that an angle formed by two surfaces of the object to be measured is obtained.